WIP support for the Hermit microkernel.

A whole bunch of close-to-the-metal crates are yielding compiler errors
upon compilation with --target x86_64-unknown-hermit. MIO is not.

Using hermit might necessitate relying on threads for IO instead of
using MIO.

https://github.com/hermit-os/kernel/issues/1043

.github/workflows/qc.yaml

@@ -25,6 +25,34 @@ jobs:
       - name: Run ShellCheck
         uses: ludeeus/action-shellcheck@master
 
+  rustfmt:
+    name: Rust Format
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v3
+      - name: Run Rust Formatting Script
+        run: bash format_rust_code.sh --mode check
+
+  cargo-bench:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v3
+      - uses: actions/cache@v3
+        with:
+          path: |
+            ~/.cargo/bin/
+            ~/.cargo/registry/index/
+            ~/.cargo/registry/cache/
+            ~/.cargo/git/db/
+            target/
+          key: ${{ runner.os }}-cargo-${{ hashFiles('**/Cargo.lock') }}
+      - name: Install libsodium
+        run: sudo apt-get install -y libsodium-dev
+        # liboqs requires quite a lot of stack memory, thus we adjust
+        # the default stack size picked for new threads (which is used
+        # by `cargo test`) to be _big enough_. Setting it to 8 MiB
+      - run: RUST_MIN_STACK=8388608 cargo bench --no-run --workspace
+
   cargo-audit:
     runs-on: ubuntu-latest
     steps:
@@ -93,7 +121,7 @@ jobs:
         # liboqs requires quite a lot of stack memory, thus we adjust
         # the default stack size picked for new threads (which is used
         # by `cargo test`) to be _big enough_. Setting it to 8 MiB
-      - run: RUST_MIN_STACK=8388608 cargo test
+      - run: RUST_MIN_STACK=8388608 cargo test --workspace
 
   cargo-test-nix-devshell-x86_64-linux:
     runs-on:
@@ -116,7 +144,7 @@ jobs:
         with:
           name: rosenpass
           authToken: ${{ secrets.CACHIX_AUTH_TOKEN }}
-      - run: nix develop --command cargo test
+      - run: nix develop --command cargo test --workspace
 
   cargo-fuzz:
     runs-on: ubuntu-latest
@@ -141,8 +169,10 @@ jobs:
         run: cargo install cargo-fuzz
       - name: Run fuzzing
         run: |
-          cargo fuzz run fuzz_aead_enc_into -- -max_total_time=60
-          cargo fuzz run fuzz_blake2b -- -max_total_time=60
-          cargo fuzz run fuzz_handle_msg -- -max_total_time=60
-          cargo fuzz run fuzz_kyber_encaps -- -max_total_time=60
-          cargo fuzz run fuzz_mceliece_encaps -- -max_total_time=60
+          cargo fuzz run fuzz_aead_enc_into -- -max_total_time=5
+          cargo fuzz run fuzz_blake2b -- -max_total_time=5
+          cargo fuzz run fuzz_handle_msg -- -max_total_time=5
+          ulimit -s 8192000 && RUST_MIN_STACK=33554432000 && cargo fuzz run fuzz_kyber_encaps -- -max_total_time=5
+          cargo fuzz run fuzz_mceliece_encaps -- -max_total_time=5
+          cargo fuzz run fuzz_box_secret_alloc -- -max_total_time=5
+          cargo fuzz run fuzz_vec_secret_alloc -- -max_total_time=5

Cargo.toml

@@ -3,16 +3,21 @@ resolver = "2"
 
 members = [
     "rosenpass",
+    "cipher-traits",
     "ciphers",
     "util",
     "constant-time",
-    "sodium",
+    "oqs",
     "to",
     "fuzz",
+    "secret-memory",
+    "lenses",
+    "wireguard-broker",
 ]
 
 default-members = [
-    "rosenpass"
+    "rosenpass",
+    "wireguard-broker"
 ]
 
 [workspace.metadata.release]
@@ -23,28 +28,37 @@ tag-prefix = ""
 rosenpass = { path = "rosenpass" }
 rosenpass-util = { path = "util" }
 rosenpass-constant-time = { path = "constant-time" }
-rosenpass-sodium = { path = "sodium" }
+rosenpass-cipher-traits = { path = "cipher-traits" }
 rosenpass-ciphers = { path = "ciphers" }
 rosenpass-to = { path = "to" }
+rosenpass-secret-memory = { path = "secret-memory" }
+rosenpass-oqs = { path = "oqs" }
+rosenpass-lenses = { path = "lenses" }
+rosenpass-wireguard-broker = { path = "wireguard-broker" }
 criterion = "0.4.0"
 test_bin = "0.4.0"
 libfuzzer-sys = "0.4"
 stacker = "0.1.15"
 doc-comment = "0.3.3"
-base64 = "0.21.1"
+base64 = "0.21.5"
 zeroize = "1.7.0"
 memoffset = "0.9.0"
-lazy_static = "1.4.0"
-thiserror = "1.0.40"
-paste = "1.0.12"
-env_logger = "0.10.0"
-toml = "0.7.4"
+thiserror = "1.0.50"
+paste = "1.0.14"
+env_logger = "0.10.1"
+toml = "0.7.8"
 static_assertions = "1.1.0"
-log = { version = "0.4.17" }
-clap = { version = "4.3.0", features = ["derive"] }
-serde = { version = "1.0.163", features = ["derive"] }
+allocator-api2 = "0.2.14"
+allocator-api2-tests = "0.2.14"
+rand = "0.8.5"
+wireguard-uapi = "3.0.0"
+typenum = "1.17.0"
+log = { version = "0.4.20" }
+clap = { version = "4.4.10", features = ["derive"] }
+serde = { version = "1.0.193", features = ["derive"] }
 arbitrary = { version = "1.3.2", features = ["derive"] }
-anyhow = { version = "1.0.71", features = ["backtrace"] }
-mio = { version = "0.8.6", features = ["net", "os-poll"] }
-libsodium-sys-stable= { version = "1.19.28", features = ["use-pkg-config"] }
-oqs-sys = { version = "0.8", default-features = false, features = ['classic_mceliece', 'kyber']  }
+anyhow = { version = "1.0.75", features = ["backtrace", "std"] }
+mio = { version = "0.8.9", features = ["net"] }
+oqs-sys = { version = "0.8", default-features = false, features = ['classic_mceliece', 'kyber']  }
+blake2 = "0.10.6"
+chacha20poly1305 = { version = "0.10.1", default-features = false, features = [ "std", "heapless" ] }

analysis/03_identity_hiding.entry.mpv

@@ -0,0 +1,121 @@
+/*
+  This identity hiding process tests whether the rosenpass protocol is able to protect the identity of an initiator or responder.
+  The participants in the test are trusted initiators, trusted responders and compromised initiators and responders.
+  The test consists of two phases. In the first phase all of the participants can communicate with each other using the rosenpass protocol.
+  An attacker observes the first phase and is able to intercept and modify messages and choose participants to communicate with each other
+
+  In the second phase if the anonymity of an initiator is being tested then one of two trusted initiators is chosen.
+  The chosen initiator communicates directly with a trusted responder.
+  If an attacker can determine which initiator was chosen then the anonymity of the initiator has been compromised.
+  Otherwise the protocol has successfully protected the initiators’ identity.
+
+  If the anonymity of a responder is being tested then one of two trusted responders is chosen instead.
+  Then an initiator communicates directly with the chosen responder.
+  If an attacker can determine which responder was chosen then the anonymity of the responder is compromised.
+  Otherwise the protocol successfully protects the identity of a responder.
+
+  The Proverif code treats the public key as synonymous with identity.
+  In the above test when a responder or initiator is chosen what is actually chosen is the public/private key pair to use for communication.
+  Traditionally when a responder or initiator is chosen they would be chosen randomly.
+  The way Proverif makes a "choice" is by simulating multiple processes, one process per choice
+  Then the processes are compared and if an association between a public key and a process can be made the test fails.
+  As the choice is at least as bad as choosing the worst possible option the credibility of the test is maintained.
+  The drawback is that Proverif is only able to tell if the identity can be brute forced but misses any probabilistic associations.
+  As usual Proverif also assumes perfect encryption and in particular assumes encryption cannot be linked to identity.
+
+  One of the tradeoffs made here is that the choice function in Proverif is slow but this is in favour of being able to write more precise tests.
+  Another issue is the choice function does not work with queries so a test needs to be run for each set of assumptions.
+  In this case the test uses secure rng and a fresh secure biscuit key.
+*/
+
+
+#include "config.mpv"
+
+#define CHAINING_KEY_EVENTS 1
+#define MESSAGE_TRANSMISSION_EVENTS 1
+#define SESSION_START_EVENTS 0
+#define RANDOMIZED_CALL_IDS 0
+#undef FULL_MODEL
+#undef SIMPLE_MODEL
+#define SIMPLE_MODEL 1
+
+#include "prelude/basic.mpv"
+#include "crypto/key.mpv"
+#include "rosenpass/oracles.mpv"
+#include "crypto/kem.mpv"
+
+#define INITIATOR_TEST
+#define NEW_TRUSTED_SEED(name)            \
+  new MCAT(name, _secret_seed):seed_prec; \
+  name <- make_trusted_seed(MCAT(name, _secret_seed)); \
+
+free D:channel [private].
+free secure_biscuit_no:Atom [private].
+free secure_sidi,secure_sidr:SessionId [private].
+free secure_psk:key [private].
+free initiator1, initiator2:kem_sk_prec.
+free responder1, responder2:kem_sk_prec.
+
+let secure_init_hello(initiator: kem_sk_tmpl, sidi : SessionId, psk: key_tmpl, responder: kem_sk_tmpl) =
+  NEW_TRUSTED_SEED(seski_trusted_seed)
+  NEW_TRUSTED_SEED(ssptr_trusted_seed)
+  Oinitiator_inner(sidi, initiator, psk, responder, seski_trusted_seed, ssptr_trusted_seed, D).
+
+let secure_resp_hello(initiator: kem_sk_tmpl, responder: kem_sk_tmpl, sidr:SessionId, sidi:SessionId, biscuit_no:Atom, psk:key_tmpl) =
+  in(D, Envelope(k, IH2b(InitHello(=sidi, epki, sctr, pidiC, auth))));
+  ih <- InitHello(sidi, epki, sctr, pidiC, auth);
+  NEW_TRUSTED_SEED(septi_trusted_seed)
+  NEW_TRUSTED_SEED(sspti_trusted_seed)
+  Oinit_hello_inner(sidr, biscuit_no, responder, psk, initiator, septi_trusted_seed, sspti_trusted_seed, ih, D).
+
+let secure_init_conf(initiator: kem_sk_tmpl, responder: kem_sk_tmpl, psk:key_tmpl, sidi:SessionId, sidr:SessionId) =
+  in(D, Envelope(k3, IC2b(InitConf(=sidi, =sidr, biscuit, auth3))));
+  ic <- InitConf(sidi,sidr,biscuit, auth3);
+  NEW_TRUSTED_SEED(seski_trusted_seed)
+  NEW_TRUSTED_SEED(ssptr_trusted_seed)
+  Oinit_conf_inner(initiator, psk, responder, ic).
+
+let secure_communication(initiator: kem_sk_tmpl, responder:kem_sk_tmpl) =
+  secure_key <- prepare_key(secure_psk);
+  (!secure_init_hello(initiator, secure_sidi, secure_key, responder))
+  | !secure_resp_hello(initiator, responder, secure_sidr, secure_sidi, secure_biscuit_no, secure_key)
+  | !(secure_init_conf(initiator, responder, secure_key, secure_sidi, secure_sidr)).
+
+let pipeChannel(D:channel, C:channel) =
+  in(D, b:bits);
+  out(C, b).
+
+fun kem_private(kem_pk): kem_sk
+  reduc forall sk_tmpl:kem_sk;
+    kem_private(kem_pub(sk_tmpl)) = sk_tmpl[private].
+
+let secretCommunication() =
+#ifdef INITIATOR_TEST
+  initiator_pk <- choice[setup_kem_pk(make_trusted_kem_sk(initiator1)), setup_kem_pk(make_trusted_kem_sk(initiator2))];
+  initiator_seed <- prepare_kem_sk(kem_private(initiator_pk)); 
+#else
+  initiator_seed <- prepare_kem_sk(trusted_kem_sk(initiator1));
+#endif
+#ifdef RESPONDER_TEST
+  responder_pk <- choice[setup_kem_pk(make_trusted_kem_sk(responder1)), setup_kem_pk(make_trusted_kem_sk(responder2))];
+  responder_seed <- prepare_kem_sk(kem_private(responder_pk));
+#else
+  responder_seed <- prepare_kem_sk(trusted_kem_sk(responder1));
+#endif
+  secure_communication(initiator_seed, responder_seed) | !pipeChannel(D, C).
+
+let reveal_pks() =
+  out(C, setup_kem_pk(make_trusted_kem_sk(responder1)));
+  out(C, setup_kem_pk(make_trusted_kem_sk(responder2)));
+  out(C, setup_kem_pk(make_trusted_kem_sk(initiator1)));
+  out(C, setup_kem_pk(make_trusted_kem_sk(initiator2))).
+
+let rosenpass_main2() = 
+  REP(INITIATOR_BOUND, Oinitiator)
+  | REP(RESPONDER_BOUND, Oinit_hello)
+  | REP(RESPONDER_BOUND, Oinit_conf).
+
+let identity_hiding_main() = 
+  0 | reveal_pks() |  rosenpass_main2() | phase 1; secretCommunication().
+
+let main = identity_hiding_main.

analysis/rosenpass/oracles.mpv

@@ -47,14 +47,16 @@ CK_EV(  event OskOinit_conf(key, key). )
 MTX_EV( event ICRjct(InitConf_t, key, kem_sk, kem_pk). )
 SES_EV( event ResponderSession(InitConf_t, key). )
 event ConsumeBiscuit(Atom, kem_sk, kem_pk, Atom).
-let Oinit_conf() = 
-  in(C, Cinit_conf(Ssskm, Spsk, Sspkt, ic));
+
+let Oinit_conf_inner(Ssskm:kem_sk_tmpl, Spsk:key_tmpl, Sspkt:kem_sk_tmpl, ic:InitConf_t) =
 #if RANDOMIZED_CALL_IDS
   new call:Atom;
 #else
   call <- Cinit_conf(Ssskm, Spsk, Sspkt, ic);
 #endif
+
   SETUP_HANDSHAKE_STATE()
+
   eski <- kem_sk0;
   epki <- kem_pk0;
   let try_ = (
@@ -72,6 +74,10 @@ let Oinit_conf() =
     0
 #endif
   ).
+  
+let Oinit_conf() = 
+  in(C, Cinit_conf(Ssskm, Spsk, Sspkt, ic));
+  Oinit_conf_inner(Ssskm, Spsk, Sspkt, ic).
 
 restriction biscuit_no:Atom, sskm:kem_sk, spkr:kem_pk, ad1:Atom, ad2:Atom;
   event(ConsumeBiscuit(biscuit_no, sskm, spkr, ad1)) && event(ConsumeBiscuit(biscuit_no, sskm, spkr, ad2))
@@ -85,8 +91,8 @@ CK_EV(  event OskOresp_hello(key, key, key). )
 MTX_EV( event RHRjct(RespHello_t, key, kem_sk, kem_pk). )
 MTX_EV( event ICSent(RespHello_t, InitConf_t, key, kem_sk, kem_pk). )
 SES_EV( event InitiatorSession(RespHello_t, key). )
-let Oresp_hello(HS_DECL_ARGS) =
-  in(C, Cresp_hello(RespHello(sidr, =sidi, ecti, scti, biscuit, auth)));
+let Oresp_hello(HS_DECL_ARGS, C_in:channel) =
+  in(C_in, Cresp_hello(RespHello(sidr, =sidi, ecti, scti, biscuit, auth)));
   rh <- RespHello(sidr, sidi, ecti, scti, biscuit, auth);
   /* try */ let ic = (
     ck_ini <- ck;
@@ -98,7 +104,7 @@ let Oresp_hello(HS_DECL_ARGS) =
     SES_EV( event InitiatorSession(rh, osk); )
     ic
   /* success */ ) in (
-    out(C, ic)
+    out(C_in, Envelope(create_mac(spkt, IC2b(ic)), IC2b(ic)))
   /* fail */ ) else (
 #if MESSAGE_TRANSMISSION_EVENTS
     event RHRjct(rh, psk, sski, spkr)
@@ -116,8 +122,8 @@ MTX_EV( event IHRjct(InitHello_t, key, kem_sk, kem_pk). )
 MTX_EV( event RHSent(InitHello_t, RespHello_t, key, kem_sk, kem_pk). )
 event ConsumeSidr(SessionId, Atom).
 event ConsumeBn(Atom, kem_sk, kem_pk, Atom).
-let Oinit_hello() = 
-  in(C, Cinit_hello(sidr, biscuit_no, Ssskm, Spsk, Sspkt, Septi, Sspti, ih));
+
+let Oinit_hello_inner(sidm:SessionId, biscuit_no:Atom, Ssskm:kem_sk_tmpl, Spsk:key_tmpl, Sspkt: kem_sk_tmpl, Septi: seed_tmpl, Sspti: seed_tmpl, ih: InitHello_t, C_out:channel) = 
 #if RANDOMIZED_CALL_IDS
   new call:Atom;
 #else
@@ -125,14 +131,19 @@ let Oinit_hello() =
 #endif
   // TODO: This is ugly
   let InitHello(sidi, epki, sctr, pidiC, auth) = ih in
+
   SETUP_HANDSHAKE_STATE()
+
   eski <- kem_sk0;
-  epti <- rng_key(setup_seed(Septi)); // RHR4
-  spti <- rng_key(setup_seed(Sspti)); // RHR5
+
   event ConsumeBn(biscuit_no, sskm, spkt, call);
   event ConsumeSidr(sidr, call);
+
+  epti <- rng_key(setup_seed(Septi)); // RHR4
+  spti <- rng_key(setup_seed(Sspti)); // RHR5
   event ConsumeSeed(Epti, setup_seed(Septi), call);
   event ConsumeSeed(Spti, setup_seed(Sspti), call);
+
   let rh = (
     INITHELLO_CONSUME()
     ck_ini <- ck;
@@ -141,7 +152,8 @@ let Oinit_hello() =
     MTX_EV( event RHSent(ih, rh, psk, sskr, spki); )
     rh
   /* success */ ) in (
-    out(C, rh)
+    out(C_out, Envelope(create_mac(spkt, RH2b(rh)), RH2b(rh)))
+
   /* fail */ ) else (
 #if MESSAGE_TRANSMISSION_EVENTS
     event IHRjct(ih, psk, sskr, spki)
@@ -150,6 +162,10 @@ let Oinit_hello() =
 #endif
   ).
 
+let Oinit_hello() = 
+  in(C, Cinit_hello(sidr, biscuit_no, Ssskm, Spsk, Sspkt, Septi, Sspti, ih));
+  Oinit_hello_inner(sidr, biscuit_no, Ssskm, Spsk, Sspkt, Septi, Sspti, ih, C).
+
 restriction sid:SessionId, ad1:Atom, ad2:Atom;
   event(ConsumeSidr(sid, ad1)) && event(ConsumeSidr(sid, ad2))
     ==> ad1 = ad2.
@@ -167,26 +183,34 @@ CK_EV( event OskOinitiator_ck(key). )
 CK_EV( event OskOinitiator(key, key, kem_sk, kem_pk, key). )
 MTX_EV( event IHSent(InitHello_t, key, kem_sk, kem_pk). )
 event ConsumeSidi(SessionId, Atom).
+
+let Oinitiator_inner(sidi: SessionId, Ssskm: kem_sk_tmpl, Spsk: key_tmpl, Sspkt: kem_sk_tmpl, Seski: seed_tmpl, Ssptr: seed_tmpl, C_out:channel) =
+  #if RANDOMIZED_CALL_IDS
+    new call:Atom;
+  #else
+    call <- Cinitiator(sidi, Ssskm, Spsk, Sspkt, Seski, Ssptr);
+  #endif
+
+    SETUP_HANDSHAKE_STATE()
+
+    sidr <- sid0;
+
+    RNG_KEM_PAIR(eski, epki, Seski) // IHI3
+    sptr <- rng_key(setup_seed(Ssptr)); // IHI5
+    event ConsumeSidi(sidi, call);
+    event ConsumeSeed(Sptr, setup_seed(Ssptr), call);
+    event ConsumeSeed(Eski, setup_seed(Seski), call);
+
+    INITHELLO_PRODUCE()
+    CK_EV( event OskOinitiator_ck(ck); ) 
+    CK_EV( event OskOinitiator(ck, psk, sski, spkr, sptr); )
+    MTX_EV( event IHSent(ih, psk, sski, spkr); )
+    out(C_out, Envelope(create_mac(spkt, IH2b(ih)), IH2b(ih)));
+    Oresp_hello(HS_PASS_ARGS, C_out).
+
 let Oinitiator() =
   in(C, Cinitiator(sidi, Ssskm, Spsk, Sspkt, Seski, Ssptr));
-#if RANDOMIZED_CALL_IDS
-  new call:Atom;
-#else
-  call <- Cinitiator(sidi, Ssskm, Spsk, Sspkt, Seski, Ssptr);
-#endif
-  SETUP_HANDSHAKE_STATE()
-  RNG_KEM_PAIR(eski, epki, Seski) // IHI3
-  sidr <- sid0;
-  sptr <- rng_key(setup_seed(Ssptr)); // IHI5
-  event ConsumeSidi(sidi, call);
-  event ConsumeSeed(Sptr, setup_seed(Ssptr), call);
-  event ConsumeSeed(Eski, setup_seed(Seski), call);
-  INITHELLO_PRODUCE()
-  CK_EV( event OskOinitiator_ck(ck); ) 
-  CK_EV( event OskOinitiator(ck, psk, sski, spkr, sptr); )
-  MTX_EV( event IHSent(ih, psk, sski, spkr); )
-  out(C, ih);
-  Oresp_hello(HS_PASS_ARGS).
+  Oinitiator_inner(sidi, Ssskm, Spsk, Sspkt, Seski, Ssptr, C).
 
 restriction sid:SessionId, ad1:Atom, ad2:Atom;
   event(ConsumeSidi(sid, ad1)) && event(ConsumeSidi(sid, ad2))

analysis/rosenpass/protocol.mpv

@@ -2,6 +2,12 @@
 #include "crypto/kem.mpv"
 #include "rosenpass/handshake_state.mpv"
 
+fun Envelope(
+  key,
+  bits
+): bits [data].
+letfun create_mac(pk:kem_pk, payload:bits) = lprf2(MAC, kem_pk2b(pk), payload).
+
 type InitHello_t.
 fun InitHello(
   SessionId, // sidi
@@ -11,6 +17,8 @@ fun InitHello(
   bits       // auth
 ) : InitHello_t [data].
 
+fun IH2b(InitHello_t) : bitstring [typeConverter].
+
 #define INITHELLO_PRODUCE()       \
   ck <- lprf1(CK_INIT, kem_pk2b(spkr)); /* IHI1 */ \
   /* not handled here */                /* IHI2 */ \
@@ -41,7 +49,9 @@ fun RespHello(
     bits       // auth
 ) : RespHello_t [data].
 
-#define RESPHELLO_PRODUCE()                   \
+fun RH2b(RespHello_t) : bitstring [typeConverter].
+
+#define RESPHELLO_PRODUCE()  \
   /* not handled here */           /* RHR1 */ \
   MIX2(sid2b(sidr), sid2b(sidi))   /* RHR3 */ \
   ENCAPS_AND_MIX(ecti, epki, epti) /* RHR4 */ \
@@ -67,6 +77,8 @@ fun InitConf(
     bits       // auth
 ) : InitConf_t [data].
 
+fun IC2b(InitConf_t) : bitstring [typeConverter].
+
 #define INITCONF_PRODUCE()                  \
   MIX2(sid2b(sidi), sid2b(sidr)) /* ICI3 */ \
   ENCRYPT_AND_MIX(auth, empty)   /* ICI4 */ \

cipher-traits/Cargo.toml

@@ -0,0 +1,12 @@
+[package]
+name = "rosenpass-cipher-traits"
+authors = ["Karolin Varner <karo@cupdev.net>", "wucke13 <wucke13@gmail.com>"]
+version = "0.1.0"
+edition = "2021"
+license = "MIT OR Apache-2.0"
+description = "Rosenpass internal traits for cryptographic primitives"
+homepage = "https://rosenpass.eu/"
+repository = "https://github.com/rosenpass/rosenpass"
+readme = "readme.md"
+
+[dependencies]

cipher-traits/readme.md

@@ -1,5 +1,5 @@
 # Rosenpass internal libsodium bindings
 
-Rosenpass internal library providing bindings to libsodium.
+Rosenpass internal library providing traits for cryptographic primitives.
 
 This is an internal library; not guarantee is made about its API at this point in time.

cipher-traits/src/kem.rs

@@ -0,0 +1,47 @@
+//! Traits and implementations for Key Encapsulation Mechanisms (KEMs)
+//!
+//! KEMs are the interface provided by almost all post-quantum
+//! secure key exchange mechanisms.
+//!
+//! Conceptually KEMs are akin to public-key encryption, but instead of encrypting
+//! arbitrary data, KEMs are limited to the transmission of keys, randomly chosen during
+//!
+//! encapsulation.
+//! The [KEM] Trait describes the basic API offered by a Key Encapsulation
+//! Mechanism. Two implementations for it are provided, [StaticKEM] and [EphemeralKEM].
+
+use std::result::Result;
+
+/// Key Encapsulation Mechanism
+///
+/// The KEM interface defines three operations: Key generation, key encapsulation and key
+/// decapsulation.
+pub trait Kem {
+    type Error;
+
+    /// Secrete Key length
+    const SK_LEN: usize;
+    /// Public Key length
+    const PK_LEN: usize;
+    /// Ciphertext length
+    const CT_LEN: usize;
+    /// Shared Secret length
+    const SHK_LEN: usize;
+
+    /// Generate a keypair consisting of secret key (`sk`) and public key (`pk`)
+    ///
+    /// `keygen() -> sk, pk`
+    fn keygen(sk: &mut [u8], pk: &mut [u8]) -> Result<(), Self::Error>;
+
+    /// From a public key (`pk`), generate a shared key (`shk`, for local use)
+    /// and a cipher text (`ct`, to be sent to the owner of the `pk`).
+    ///
+    /// `encaps(pk) -> shk, ct`
+    fn encaps(shk: &mut [u8], ct: &mut [u8], pk: &[u8]) -> Result<(), Self::Error>;
+
+    /// From a secret key (`sk`) and a cipher text (`ct`) derive a shared key
+    /// (`shk`)
+    ///
+    /// `decaps(sk, ct) -> shk`
+    fn decaps(shk: &mut [u8], sk: &[u8], ct: &[u8]) -> Result<(), Self::Error>;
+}

cipher-traits/src/lib.rs

@@ -0,0 +1,2 @@
+mod kem;
+pub use kem::Kem;

ciphers/Cargo.toml

@@ -11,8 +11,12 @@ readme = "readme.md"
 
 [dependencies]
 anyhow = { workspace = true }
-rosenpass-sodium = { workspace = true }
 rosenpass-to = { workspace = true }
 rosenpass-constant-time = { workspace = true }
+rosenpass-secret-memory = { workspace = true }
+rosenpass-oqs = { workspace = true }
+rosenpass-util = { workspace = true }
 static_assertions = { workspace = true }
 zeroize = { workspace = true }
+chacha20poly1305 = { workspace = true }
+blake2 = { workspace = true }

ciphers/src/hash_domain.rs

@@ -0,0 +1,109 @@
+use anyhow::Result;
+use rosenpass_secret_memory::Secret;
+use rosenpass_to::To;
+
+use crate::subtle::incorrect_hmac_blake2b as hash;
+
+pub use hash::KEY_LEN;
+
+// TODO Use a proper Dec interface
+#[derive(Clone, Debug)]
+pub struct HashDomain([u8; KEY_LEN]);
+#[derive(Clone, Debug)]
+pub struct HashDomainNamespace([u8; KEY_LEN]);
+#[derive(Clone, Debug)]
+pub struct SecretHashDomain(Secret<KEY_LEN>);
+#[derive(Clone, Debug)]
+pub struct SecretHashDomainNamespace(Secret<KEY_LEN>);
+
+impl HashDomain {
+    pub fn zero() -> Self {
+        Self([0u8; KEY_LEN])
+    }
+
+    pub fn dup(self) -> HashDomainNamespace {
+        HashDomainNamespace(self.0)
+    }
+
+    pub fn turn_secret(self) -> SecretHashDomain {
+        SecretHashDomain(Secret::from_slice(&self.0))
+    }
+
+    // TODO: Protocol! Use domain separation to ensure that
+    pub fn mix(self, v: &[u8]) -> Result<Self> {
+        Ok(Self(hash::hash(&self.0, v).collect::<[u8; KEY_LEN]>()?))
+    }
+
+    pub fn mix_secret<const N: usize>(self, v: Secret<N>) -> Result<SecretHashDomain> {
+        SecretHashDomain::invoke_primitive(&self.0, v.secret())
+    }
+
+    pub fn into_value(self) -> [u8; KEY_LEN] {
+        self.0
+    }
+}
+
+impl HashDomainNamespace {
+    pub fn mix(&self, v: &[u8]) -> Result<HashDomain> {
+        Ok(HashDomain(
+            hash::hash(&self.0, v).collect::<[u8; KEY_LEN]>()?,
+        ))
+    }
+
+    pub fn mix_secret<const N: usize>(&self, v: Secret<N>) -> Result<SecretHashDomain> {
+        SecretHashDomain::invoke_primitive(&self.0, v.secret())
+    }
+}
+
+impl SecretHashDomain {
+    pub fn invoke_primitive(k: &[u8], d: &[u8]) -> Result<SecretHashDomain> {
+        let mut r = SecretHashDomain(Secret::zero());
+        hash::hash(k, d).to(r.0.secret_mut())?;
+        Ok(r)
+    }
+
+    pub fn zero() -> Self {
+        Self(Secret::zero())
+    }
+
+    pub fn dup(self) -> SecretHashDomainNamespace {
+        SecretHashDomainNamespace(self.0)
+    }
+
+    pub fn danger_from_secret(k: Secret<KEY_LEN>) -> Self {
+        Self(k)
+    }
+
+    pub fn mix(self, v: &[u8]) -> Result<SecretHashDomain> {
+        Self::invoke_primitive(self.0.secret(), v)
+    }
+
+    pub fn mix_secret<const N: usize>(self, v: Secret<N>) -> Result<SecretHashDomain> {
+        Self::invoke_primitive(self.0.secret(), v.secret())
+    }
+
+    pub fn into_secret(self) -> Secret<KEY_LEN> {
+        self.0
+    }
+
+    pub fn into_secret_slice(mut self, v: &[u8], dst: &[u8]) -> Result<()> {
+        hash::hash(v, dst).to(self.0.secret_mut())
+    }
+}
+
+impl SecretHashDomainNamespace {
+    pub fn mix(&self, v: &[u8]) -> Result<SecretHashDomain> {
+        SecretHashDomain::invoke_primitive(self.0.secret(), v)
+    }
+
+    pub fn mix_secret<const N: usize>(&self, v: Secret<N>) -> Result<SecretHashDomain> {
+        SecretHashDomain::invoke_primitive(self.0.secret(), v.secret())
+    }
+
+    // TODO: This entire API is not very nice; we need this for biscuits, but
+    // it might be better to extract a special "biscuit"
+    // labeled subkey and reinitialize the chain with this
+    pub fn danger_into_secret(self) -> Secret<KEY_LEN> {
+        self.0
+    }
+}

ciphers/src/lib.rs

@@ -5,24 +5,23 @@ pub mod subtle;
 pub const KEY_LEN: usize = 32;
 const_assert!(KEY_LEN == aead::KEY_LEN);
 const_assert!(KEY_LEN == xaead::KEY_LEN);
-const_assert!(KEY_LEN == hash::KEY_LEN);
+const_assert!(KEY_LEN == hash_domain::KEY_LEN);
 
 /// Authenticated encryption with associated data
 pub mod aead {
-    pub use rosenpass_sodium::aead::chacha20poly1305_ietf::{
-        decrypt, encrypt, KEY_LEN, NONCE_LEN, TAG_LEN,
-    };
+    pub use crate::subtle::chacha20poly1305_ietf::{decrypt, encrypt, KEY_LEN, NONCE_LEN, TAG_LEN};
 }
 
 /// Authenticated encryption with associated data with a constant nonce
 pub mod xaead {
-    pub use rosenpass_sodium::aead::xchacha20poly1305_ietf::{
+    pub use crate::subtle::xchacha20poly1305_ietf::{
         decrypt, encrypt, KEY_LEN, NONCE_LEN, TAG_LEN,
     };
 }
 
-pub mod hash {
-    pub use crate::subtle::incorrect_hmac_blake2b::{
-        hash, KEY_LEN, KEY_MAX, KEY_MIN, OUT_MAX, OUT_MIN,
-    };
+pub mod hash_domain;
+
+pub mod kem {
+    pub use rosenpass_oqs::ClassicMceliece460896 as StaticKem;
+    pub use rosenpass_oqs::Kyber512 as EphemeralKem;
 }

ciphers/src/subtle/blake2b.rs

@@ -0,0 +1,42 @@
+use zeroize::Zeroizing;
+
+use blake2::digest::crypto_common::generic_array::GenericArray;
+use blake2::digest::crypto_common::typenum::U32;
+use blake2::digest::crypto_common::KeySizeUser;
+use blake2::digest::{FixedOutput, Mac, OutputSizeUser};
+use blake2::Blake2bMac;
+
+use rosenpass_to::{ops::copy_slice, with_destination, To};
+use rosenpass_util::typenum2const;
+
+type Impl = Blake2bMac<U32>;
+
+type KeyLen = <Impl as KeySizeUser>::KeySize;
+type OutLen = <Impl as OutputSizeUser>::OutputSize;
+
+const KEY_LEN: usize = typenum2const! { KeyLen };
+const OUT_LEN: usize = typenum2const! { OutLen };
+
+pub const KEY_MIN: usize = KEY_LEN;
+pub const KEY_MAX: usize = KEY_LEN;
+pub const OUT_MIN: usize = OUT_LEN;
+pub const OUT_MAX: usize = OUT_LEN;
+
+#[inline]
+pub fn hash<'a>(key: &'a [u8], data: &'a [u8]) -> impl To<[u8], anyhow::Result<()>> + 'a {
+    with_destination(|out: &mut [u8]| {
+        let mut h = Impl::new_from_slice(key)?;
+        h.update(data);
+
+        // Jesus christ, blake2 crate, your usage of GenericArray might be nice and fancy
+        // but it introduces a ton of complexity. This cost me half an hour just to figure
+        // out the right way to use the imports while allowing for zeroization.
+        // An API based on slices might actually be simpler.
+        let mut tmp = Zeroizing::new([0u8; OUT_LEN]);
+        let mut tmp = GenericArray::from_mut_slice(tmp.as_mut());
+        h.finalize_into(&mut tmp);
+        copy_slice(tmp.as_ref()).to(out);
+
+        Ok(())
+    })
+}

ciphers/src/subtle/chacha20poly1305_ietf.rs

@@ -0,0 +1,43 @@
+use rosenpass_to::ops::copy_slice;
+use rosenpass_to::To;
+use rosenpass_util::typenum2const;
+
+use chacha20poly1305::aead::generic_array::GenericArray;
+use chacha20poly1305::ChaCha20Poly1305 as AeadImpl;
+use chacha20poly1305::{AeadCore, AeadInPlace, KeyInit, KeySizeUser};
+
+pub const KEY_LEN: usize = typenum2const! { <AeadImpl as KeySizeUser>::KeySize };
+pub const TAG_LEN: usize = typenum2const! { <AeadImpl as AeadCore>::TagSize };
+pub const NONCE_LEN: usize = typenum2const! { <AeadImpl as AeadCore>::NonceSize };
+
+#[inline]
+pub fn encrypt(
+    ciphertext: &mut [u8],
+    key: &[u8],
+    nonce: &[u8],
+    ad: &[u8],
+    plaintext: &[u8],
+) -> anyhow::Result<()> {
+    let nonce = GenericArray::from_slice(nonce);
+    let (ct, mac) = ciphertext.split_at_mut(ciphertext.len() - TAG_LEN);
+    copy_slice(plaintext).to(ct);
+    let mac_value = AeadImpl::new_from_slice(key)?.encrypt_in_place_detached(&nonce, ad, ct)?;
+    copy_slice(&mac_value[..]).to(mac);
+    Ok(())
+}
+
+#[inline]
+pub fn decrypt(
+    plaintext: &mut [u8],
+    key: &[u8],
+    nonce: &[u8],
+    ad: &[u8],
+    ciphertext: &[u8],
+) -> anyhow::Result<()> {
+    let nonce = GenericArray::from_slice(nonce);
+    let (ct, mac) = ciphertext.split_at(ciphertext.len() - TAG_LEN);
+    let tag = GenericArray::from_slice(mac);
+    copy_slice(ct).to(plaintext);
+    AeadImpl::new_from_slice(key)?.decrypt_in_place_detached(&nonce, ad, plaintext, tag)?;
+    Ok(())
+}

ciphers/src/subtle/incorrect_hmac_blake2b.rs

@@ -1,9 +1,11 @@
 use anyhow::ensure;
-use rosenpass_constant_time::xor;
-use rosenpass_sodium::hash::blake2b;
-use rosenpass_to::{ops::copy_slice, with_destination, To};
 use zeroize::Zeroizing;
 
+use rosenpass_constant_time::xor;
+use rosenpass_to::{ops::copy_slice, with_destination, To};
+
+use crate::subtle::blake2b;
+
 pub const KEY_LEN: usize = 32;
 pub const KEY_MIN: usize = KEY_LEN;
 pub const KEY_MAX: usize = KEY_LEN;

ciphers/src/subtle/mod.rs

@@ -1 +1,4 @@
+pub mod blake2b;
+pub mod chacha20poly1305_ietf;
 pub mod incorrect_hmac_blake2b;
+pub mod xchacha20poly1305_ietf;

ciphers/src/subtle/xchacha20poly1305_ietf.rs

@@ -0,0 +1,45 @@
+use rosenpass_to::ops::copy_slice;
+use rosenpass_to::To;
+use rosenpass_util::typenum2const;
+
+use chacha20poly1305::aead::generic_array::GenericArray;
+use chacha20poly1305::XChaCha20Poly1305 as AeadImpl;
+use chacha20poly1305::{AeadCore, AeadInPlace, KeyInit, KeySizeUser};
+
+pub const KEY_LEN: usize = typenum2const! { <AeadImpl as KeySizeUser>::KeySize };
+pub const TAG_LEN: usize = typenum2const! { <AeadImpl as AeadCore>::TagSize };
+pub const NONCE_LEN: usize = typenum2const! { <AeadImpl as AeadCore>::NonceSize };
+
+#[inline]
+pub fn encrypt(
+    ciphertext: &mut [u8],
+    key: &[u8],
+    nonce: &[u8],
+    ad: &[u8],
+    plaintext: &[u8],
+) -> anyhow::Result<()> {
+    let nonce = GenericArray::from_slice(nonce);
+    let (n, ct_mac) = ciphertext.split_at_mut(NONCE_LEN);
+    let (ct, mac) = ct_mac.split_at_mut(ct_mac.len() - TAG_LEN);
+    copy_slice(nonce).to(n);
+    copy_slice(plaintext).to(ct);
+    let mac_value = AeadImpl::new_from_slice(key)?.encrypt_in_place_detached(&nonce, ad, ct)?;
+    copy_slice(&mac_value[..]).to(mac);
+    Ok(())
+}
+
+#[inline]
+pub fn decrypt(
+    plaintext: &mut [u8],
+    key: &[u8],
+    ad: &[u8],
+    ciphertext: &[u8],
+) -> anyhow::Result<()> {
+    let (n, ct_mac) = ciphertext.split_at(NONCE_LEN);
+    let (ct, mac) = ct_mac.split_at(ct_mac.len() - TAG_LEN);
+    let nonce = GenericArray::from_slice(n);
+    let tag = GenericArray::from_slice(mac);
+    copy_slice(ct).to(plaintext);
+    AeadImpl::new_from_slice(key)?.decrypt_in_place_detached(&nonce, ad, plaintext, tag)?;
+    Ok(())
+}

constant-time/src/lib.rs

@@ -1,3 +1,5 @@
+use core::hint::black_box;
+
 use rosenpass_to::{with_destination, To};
 
 /// Xors the source into the destination
@@ -16,11 +18,61 @@ use rosenpass_to::{with_destination, To};
 ///
 /// If source and destination are of different sizes.
 #[inline]
-pub fn xor<'a>(src: &'a [u8]) -> impl To<[u8], ()> + 'a {
+pub fn xor(src: &[u8]) -> impl To<[u8], ()> + '_ {
     with_destination(|dst: &mut [u8]| {
-        assert!(src.len() == dst.len());
+        assert!(black_box(src.len()) == black_box(dst.len()));
         for (dv, sv) in dst.iter_mut().zip(src.iter()) {
-            *dv ^= *sv;
+            *black_box(dv) ^= black_box(*sv);
         }
     })
 }
+
+#[inline]
+pub fn memcmp(a: &[u8], b: &[u8]) -> bool {
+    a == b
+}
+
+#[inline]
+pub fn compare(a: &[u8], b: &[u8]) -> i32 {
+    assert!(a.len() == b.len());
+    a.cmp(b) as i32
+}
+
+/// Interpret the given slice as a little-endian unsigned integer
+/// and increment that integer.
+///
+/// # Examples
+///
+/// ```
+/// use rosenpass_constant_time::increment as inc;
+/// use rosenpass_to::To;
+///
+/// fn testcase(v: &[u8], correct: &[u8]) {
+///   let mut v = v.to_owned();
+///   inc(&mut v);
+///   assert_eq!(&v, correct);
+/// }
+///
+/// testcase(b"", b"");
+/// testcase(b"\x00", b"\x01");
+/// testcase(b"\x01", b"\x02");
+/// testcase(b"\xfe", b"\xff");
+/// testcase(b"\xff", b"\x00");
+/// testcase(b"\x00\x00", b"\x01\x00");
+/// testcase(b"\x01\x00", b"\x02\x00");
+/// testcase(b"\xfe\x00", b"\xff\x00");
+/// testcase(b"\xff\x00", b"\x00\x01");
+/// testcase(b"\x00\x00\x00\x00\x00\x00", b"\x01\x00\x00\x00\x00\x00");
+/// testcase(b"\x00\xa3\x00\x77\x00\x00", b"\x01\xa3\x00\x77\x00\x00");
+/// testcase(b"\xff\xa3\x00\x77\x00\x00", b"\x00\xa4\x00\x77\x00\x00");
+/// testcase(b"\xff\xff\xff\x77\x00\x00", b"\x00\x00\x00\x78\x00\x00");
+/// ```
+#[inline]
+pub fn increment(v: &mut [u8]) {
+    let mut carry = 1u8;
+    for val in v.iter_mut() {
+        let (v, c) = black_box(*val).overflowing_add(black_box(carry));
+        *black_box(val) = v;
+        *black_box(&mut carry) = black_box(black_box(c) as u8);
+    }
+}

doc/rosenpass.1

@@ -23,7 +23,7 @@ If you are not specifically tasked with developing post-quantum secure systems,
 you probably do not need this tool.
 .Ss COMMANDS
 .Bl -tag -width Ds
-.It Ar keygen private-key <file-path> public-key <file-path>
+.It Ar gen-keys --secret-key <file-path> --public-key <file-path>
 Generate a keypair to use in the exchange command later.
 Send the public-key file to your communication partner and keep the private-key
 file secret!

flake.nix

@@ -291,7 +291,6 @@
               ];
               buildPhase = ''
                 export HOME=$(mktemp -d)
-                export OSFONTDIR="$(kpsewhich --var-value TEXMF)/fonts/{opentype/public/nunito,truetype/google/noto}"
                 latexmk -r tex/CI.rc
               '';
               installPhase = ''

format_rust_code.sh

@@ -0,0 +1,115 @@
+#!/usr/bin/env bash
+
+# Parse command line options
+while [[ $# -gt 0 ]]; do
+    case "$1" in
+        --mode)
+            mode="$2"
+            shift 2
+            ;;
+        *)
+            echo "Unknown option: $1"
+            exit 1
+            ;;
+    esac
+done
+
+# Check if mode is specified
+if [ -z "$mode" ]; then
+    echo "Please specify the mode using --mode option. Valid modes are 'check' and 'fix'."
+    exit 1
+fi
+
+# Find all Markdown files in the current directory and its subdirectories
+mapfile -t md_files < <(find . -type f -name "*.md")
+
+count=0
+# Iterate through each Markdown file
+for file in "${md_files[@]}"; do
+    # Use awk to extract Rust code blocks enclosed within triple backticks
+    rust_code_blocks=$(awk '/```rust/{flag=1; next}/```/{flag=0} flag' "$file")
+
+    # Count the number of Rust code blocks
+    num_fences=$(awk '/```rust/{f=1} f{if(/```/){f=0; count++}} END{print count}' "$file")
+
+    if [ -n "$rust_code_blocks" ]; then
+        echo "Processing Rust code in $file"
+        # Iterate through each Rust code block
+        for ((i=1; i <= num_fences ; i++)); do
+            # Extract individual Rust code block using awk
+            current_rust_block=$(awk -v i="$i" '/```rust/{f=1; if (++count == i) next} f&&/```/{f=0;next} f' "$file")
+            # Variable to check if we have added the main function
+            add_main=0  
+            # Check if the Rust code block is already inside a function
+            if ! echo "$current_rust_block" | grep -q "fn main()"; then
+                # If not, wrap it in a main function
+                current_rust_block=$'fn main() {\n'"$current_rust_block"$'\n}'
+                add_main=1
+            fi
+            if [ "$mode" == "check" ]; then
+                # Apply changes to the Rust code block
+                formatted_rust_code=$(echo "$current_rust_block" | rustfmt)
+                # Use rustfmt to format the Rust code block, remove first and last lines, and remove the first 4 spaces if added  main function
+                if [ "$add_main" == 1 ]; then
+                    formatted_rust_code=$(echo "$formatted_rust_code" | sed '1d;$d' | sed 's/^    //')
+                    current_rust_block=$(echo "$current_rust_block" | sed '1d;')
+                    current_rust_block=$(echo "$current_rust_block" | sed '$d')
+                fi
+                if [ "$formatted_rust_code" == "$current_rust_block" ]; then
+                    echo "No changes needed in Rust code block $i in $file"
+                else
+                    echo -e "\nChanges needed in Rust code block $i in $file:\n"
+                    echo "$formatted_rust_code"
+                    count=+1
+                fi
+
+            elif [ "$mode" == "fix" ]; then
+                # Replace current_rust_block with formatted_rust_code in the file
+                formatted_rust_code=$(echo "$current_rust_block" | rustfmt)
+                # Use rustfmt to format the Rust code block, remove first and last lines, and remove the first 4 spaces if added  main function
+                if [ "$add_main" == 1 ]; then
+                    formatted_rust_code=$(echo "$formatted_rust_code" | sed '1d;$d' | sed 's/^    //')
+                    current_rust_block=$(echo "$current_rust_block" | sed '1d;')
+                    current_rust_block=$(echo "$current_rust_block" | sed '$d')
+                fi
+                # Check if the formatted code is the same as the current Rust code block
+                if [ "$formatted_rust_code" == "$current_rust_block" ]; then
+                    echo "No changes needed in Rust code block $i in $file"
+                else
+                    echo "Formatting Rust code block $i in $file"
+                    # Replace current_rust_block with formatted_rust_code in the file
+                    # Use awk to find the line number of the pattern
+
+                    start_line=$(grep -n "^\`\`\`rust" "$file" | sed -n "${i}p" | cut -d: -f1)
+                    end_line=$(grep -n "^\`\`\`" "$file" | awk -F: -v start_line="$start_line" '$1 > start_line {print $1; exit;}')
+
+                    if [ -n "$start_line" ] && [ -n "$end_line" ]; then
+                        # Print lines before the Rust code block
+                        head -n "$((start_line - 1))" "$file"
+
+                        # Print the formatted Rust code block
+                        echo "\`\`\`rust"
+                        echo "$formatted_rust_code"
+                        echo "\`\`\`"
+
+                        # Print lines after the Rust code block
+                        tail -n +"$((end_line + 1))" "$file"
+                    else
+                        # Rust code block not found or end line not found
+                        cat "$file"
+                    fi > tmpfile && mv tmpfile "$file"
+
+                fi
+            else  
+                echo "Unknown mode: $mode. Valid modes are 'check' and 'fix'."
+                exit 1
+            fi
+        done
+    fi
+done
+
+# CI failure if changes are needed
+if [ $count -gt 0 ]; then
+    echo "CI failed: Changes needed in Rust code blocks."
+    exit 1
+fi

fuzz/Cargo.toml

@@ -11,8 +11,9 @@ cargo-fuzz = true
 arbitrary = { workspace = true }
 libfuzzer-sys = { workspace = true }
 stacker = { workspace = true }
-rosenpass-sodium = { workspace = true }
+rosenpass-secret-memory = { workspace = true }
 rosenpass-ciphers = { workspace = true }
+rosenpass-cipher-traits = { workspace = true }
 rosenpass-to = { workspace = true }
 rosenpass = { workspace = true }
 
@@ -45,3 +46,15 @@ name = "fuzz_kyber_encaps"
 path = "fuzz_targets/kyber_encaps.rs"
 test = false
 doc = false
+
+[[bin]]
+name = "fuzz_box_secret_alloc"
+path = "fuzz_targets/box_secret_alloc.rs"
+test = false
+doc = false
+
+[[bin]]
+name = "fuzz_vec_secret_alloc"
+path = "fuzz_targets/vec_secret_alloc.rs"
+test = false
+doc = false

fuzz/fuzz_targets/aead_enc_into.rs

@@ -5,7 +5,6 @@ extern crate rosenpass;
 use libfuzzer_sys::fuzz_target;
 
 use rosenpass_ciphers::aead;
-use rosenpass_sodium::init as sodium_init;
 
 #[derive(arbitrary::Arbitrary, Debug)]
 pub struct Input {
@@ -16,8 +15,6 @@ pub struct Input {
 }
 
 fuzz_target!(|input: Input| {
-    sodium_init().unwrap();
-
     let mut ciphertext: Vec<u8> = Vec::with_capacity(input.plaintext.len() + 16);
     ciphertext.resize(input.plaintext.len() + 16, 0);
 

fuzz/fuzz_targets/blake2b.rs

@@ -4,7 +4,7 @@ extern crate rosenpass;
 
 use libfuzzer_sys::fuzz_target;
 
-use rosenpass_sodium::{hash::blake2b, init as sodium_init};
+use rosenpass_ciphers::subtle::blake2b;
 use rosenpass_to::To;
 
 #[derive(arbitrary::Arbitrary, Debug)]
@@ -14,8 +14,6 @@ pub struct Blake2b {
 }
 
 fuzz_target!(|input: Blake2b| {
-    sodium_init().unwrap();
-
     let mut out = [0u8; 32];
 
     blake2b::hash(&input.key, &input.data).to(&mut out).unwrap();

fuzz/fuzz_targets/box_secret_alloc.rs

@@ -0,0 +1,8 @@
+#![no_main]
+
+use libfuzzer_sys::fuzz_target;
+use rosenpass_secret_memory::alloc::secret_box;
+
+fuzz_target!(|data: &[u8]| {
+    let _ = secret_box(data);
+});

fuzz/fuzz_targets/handle_msg.rs

@@ -3,13 +3,10 @@ extern crate rosenpass;
 
 use libfuzzer_sys::fuzz_target;
 
-use rosenpass::coloring::Secret;
 use rosenpass::protocol::CryptoServer;
-use rosenpass_sodium::init as sodium_init;
+use rosenpass_secret_memory::Secret;
 
 fuzz_target!(|rx_buf: &[u8]| {
-    sodium_init().unwrap();
-
     let sk = Secret::from_slice(&[0; 13568]);
     let pk = Secret::from_slice(&[0; 524160]);
 

fuzz/fuzz_targets/kyber_encaps.rs

@@ -4,7 +4,8 @@ extern crate rosenpass;
 
 use libfuzzer_sys::fuzz_target;
 
-use rosenpass::pqkem::{EphemeralKEM, KEM};
+use rosenpass_cipher_traits::Kem;
+use rosenpass_ciphers::kem::EphemeralKem;
 
 #[derive(arbitrary::Arbitrary, Debug)]
 pub struct Input {
@@ -15,5 +16,5 @@ fuzz_target!(|input: Input| {
     let mut ciphertext = [0u8; 768];
     let mut shared_secret = [0u8; 32];
 
-    EphemeralKEM::encaps(&mut shared_secret, &mut ciphertext, &input.pk).unwrap();
+    EphemeralKem::encaps(&mut shared_secret, &mut ciphertext, &input.pk).unwrap();
 });

fuzz/fuzz_targets/mceliece_encaps.rs

@@ -3,12 +3,13 @@ extern crate rosenpass;
 
 use libfuzzer_sys::fuzz_target;
 
-use rosenpass::pqkem::{StaticKEM, KEM};
+use rosenpass_cipher_traits::Kem;
+use rosenpass_ciphers::kem::StaticKem;
 
-fuzz_target!(|input: &[u8]| {
+fuzz_target!(|input: [u8; StaticKem::PK_LEN]| {
     let mut ciphertext = [0u8; 188];
     let mut shared_secret = [0u8; 32];
 
     // We expect errors while fuzzing therefore we do not check the result.
-    let _ = StaticKEM::encaps(&mut shared_secret, &mut ciphertext, input);
+    let _ = StaticKem::encaps(&mut shared_secret, &mut ciphertext, &input);
 });

fuzz/fuzz_targets/vec_secret_alloc.rs

@@ -0,0 +1,9 @@
+#![no_main]
+
+use libfuzzer_sys::fuzz_target;
+use rosenpass_secret_memory::alloc::secret_vec;
+
+fuzz_target!(|data: &[u8]| {
+    let mut vec = secret_vec();
+    vec.extend_from_slice(data);
+});

lenses/Cargo.toml

@@ -0,0 +1,16 @@
+[package]
+name = "rosenpass-lenses"
+version = "0.1.0"
+authors = ["Karolin Varner <karo@cupdev.net>", "wucke13 <wucke13@gmail.com>"]
+edition = "2021"
+license = "MIT OR Apache-2.0"
+description = "Rosenpass internal library for parsing binary data securely"
+homepage = "https://rosenpass.eu/"
+repository = "https://github.com/rosenpass/rosenpass"
+readme = "readme.md"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]
+paste = { workspace = true }
+thiserror = { workspace = true }

lenses/readme.md

@@ -0,0 +1,3 @@
+# Rosenpass internal binary parsing library
+
+This is an internal library; no guarantee is made about its API at this point in time.

lenses/src/lib.rs

@@ -0,0 +1,206 @@
+use std::result::Result;
+
+/// Common trait shared by all Lenses
+pub trait LenseView {
+    const LEN: usize;
+}
+
+/// Error during lense creation
+#[derive(thiserror::Error, Debug, Eq, PartialEq, Clone)]
+pub enum LenseError {
+    #[error("buffer size mismatch")]
+    BufferSizeMismatch,
+}
+
+pub type LenseResult<T> = Result<T, LenseError>;
+
+impl LenseError {
+    pub fn ensure_exact_buffer_size(len: usize, required: usize) -> LenseResult<()> {
+        (len == required)
+            .then_some(())
+            .ok_or(LenseError::BufferSizeMismatch)
+    }
+
+    pub fn ensure_sufficient_buffer_size(len: usize, required: usize) -> LenseResult<()> {
+        (len >= required)
+            .then_some(())
+            .ok_or(LenseError::BufferSizeMismatch)
+    }
+}
+
+/// A macro to create data lenses.
+#[macro_export]
+macro_rules! lense(
+    // prefix          @ offset       ; optional meta    ; field name   : field length, ...
+    (token_muncher_ref @ $offset:expr ; $( $attr:meta )* ; $field:ident : $len:expr $(, $( $tail:tt )+ )?) =>  {
+        ::paste::paste!{
+
+        #[allow(rustdoc::broken_intra_doc_links)]
+        $( #[ $attr ] )*
+        ///
+        #[doc = lense!(maybe_docstring_link $len)]
+        /// bytes long
+        pub fn $field(&self) -> &__ContainerType::Output {
+            &self.0[$offset .. $offset + $len]
+        }
+
+        /// The bytes until the
+        #[doc = lense!(maybe_docstring_link Self::$field)]
+        /// field
+        pub fn [< until_ $field >](&self) -> &__ContainerType::Output {
+            &self.0[0 .. $offset]
+        }
+
+        // if the tail exits, consume it as well
+        $(
+        lense!{token_muncher_ref @ $offset + $len ; $( $tail )+ }
+        )?
+        }
+    };
+
+    // prefix          @ offset       ; optional meta    ; field name   : field length, ...
+    (token_muncher_mut @ $offset:expr ; $( $attr:meta )* ; $field:ident : $len:expr $(, $( $tail:tt )+ )?) =>  {
+        ::paste::paste!{
+
+        #[allow(rustdoc::broken_intra_doc_links)]
+        $( #[ $attr ] )*
+        ///
+        #[doc = lense!(maybe_docstring_link $len)]
+        /// bytes long
+        pub fn [< $field _mut >](&mut self) -> &mut __ContainerType::Output {
+            &mut self.0[$offset .. $offset + $len]
+        }
+
+        // if the tail exits, consume it as well
+        $(
+        lense!{token_muncher_mut @ $offset + $len ; $( $tail )+ }
+        )?
+        }
+    };
+
+    // switch that yields literals unchanged, but creates docstring links to
+    // constants
+    // TODO the doc string link doesn't work if $x is taken from a generic,
+    (maybe_docstring_link $x:literal) => (stringify!($x));
+    (maybe_docstring_link $x:expr) => (stringify!([$x]));
+
+    // struct name  < optional generics     >    := optional doc string      field name   : field length, ...
+($type:ident $( < $( $generic:ident ),+ > )? := $( $( #[ $attr:meta ] )* $field:ident : $len:expr ),+) => (::paste::paste!{
+
+        #[allow(rustdoc::broken_intra_doc_links)]
+        /// A data lense to manipulate byte slices.
+        ///
+        //// # Fields
+        ///
+        $(
+        /// - `
+        #[doc = stringify!($field)]
+        /// `:
+        #[doc = lense!(maybe_docstring_link $len)]
+        /// bytes
+        )+
+        pub struct $type<__ContainerType $(, $( $generic ),+ )? > (
+            __ContainerType,
+            // The phantom data is required, since all generics declared on a
+            // type need to be used on the type.
+            // https://doc.rust-lang.org/stable/error_codes/E0392.html
+            $( $( ::core::marker::PhantomData<$generic> ),+ )?
+        );
+
+        impl<__ContainerType $(, $( $generic: LenseView ),+ )? > $type<__ContainerType $(, $( $generic ),+ )? >{
+            $(
+            /// Size in bytes of the field `
+            #[doc = !($field)]
+            /// `
+            pub const fn [< $field _len >]() -> usize{
+                $len
+            }
+            )+
+
+            /// Verify that `len` exactly holds [Self]
+            pub fn check_size(len: usize) -> ::rosenpass_lenses::LenseResult<()> {
+                ::rosenpass_lenses::LenseError::ensure_exact_buffer_size(len, $( $len + )+ 0)
+            }
+        }
+
+        // read-only accessor functions
+        impl<'a, __ContainerType $(, $( $generic: LenseView ),+ )?> $type<&'a __ContainerType $(, $( $generic ),+ )?>
+        where
+            __ContainerType: std::ops::Index<std::ops::Range<usize>> + ?Sized,
+        {
+            lense!{token_muncher_ref @ 0 ; $( $( $attr )* ; $field : $len ),+ }
+
+            /// View into all bytes belonging to this Lense
+            pub fn all_bytes(&self) -> &__ContainerType::Output {
+                &self.0[0..Self::LEN]
+            }
+        }
+
+        // mutable accessor functions
+        impl<'a, __ContainerType $(, $( $generic: LenseView ),+ )?> $type<&'a mut __ContainerType $(, $( $generic ),+ )?>
+        where
+            __ContainerType: std::ops::IndexMut<std::ops::Range<usize>> + ?Sized,
+        {
+            lense!{token_muncher_ref @ 0 ; $( $( $attr )* ; $field : $len ),+ }
+            lense!{token_muncher_mut @ 0 ; $( $( $attr )* ; $field : $len ),+ }
+
+            /// View into all bytes belonging to this Lense
+            pub fn all_bytes(&self) -> &__ContainerType::Output {
+                &self.0[0..Self::LEN]
+            }
+
+            /// View into all bytes belonging to this Lense
+            pub fn all_bytes_mut(&mut self) -> &mut __ContainerType::Output {
+                &mut self.0[0..Self::LEN]
+            }
+        }
+
+        // lense trait, allowing us to know the implementing lenses size
+        impl<__ContainerType $(, $( $generic: LenseView ),+ )? > LenseView for $type<__ContainerType $(, $( $generic ),+ )? >{
+            /// Number of bytes required to store this type in binary format
+            const LEN: usize = $( $len + )+ 0;
+        }
+
+        /// Extension trait to allow checked creation of a lense over
+        /// some byte slice that contains a
+        #[doc = lense!(maybe_docstring_link $type)]
+        pub trait [< $type Ext >] {
+            type __ContainerType;
+
+            /// Create a lense to the byte slice
+            fn [< $type:snake >] $(< $($generic : LenseView),* >)? (self) -> ::rosenpass_lenses::LenseResult< $type<Self::__ContainerType, $( $($generic),+ )? >>;
+
+            /// Create a lense to the byte slice, automatically truncating oversized buffers
+            fn [< $type:snake _ truncating >] $(< $($generic : LenseView),* >)? (self) -> ::rosenpass_lenses::LenseResult< $type<Self::__ContainerType, $( $($generic),+ )? >>;
+        }
+
+        impl<'a> [< $type Ext >] for &'a [u8] {
+            type __ContainerType = &'a [u8];
+
+            fn [< $type:snake >] $(< $($generic : LenseView),* >)? (self) -> ::rosenpass_lenses::LenseResult< $type<Self::__ContainerType, $( $($generic),+ )? >> {
+                $type::<Self::__ContainerType, $( $($generic),+ )? >::check_size(self.len())?;
+                Ok($type ( self, $( $( ::core::marker::PhantomData::<$generic>  ),+ )? ))
+            }
+
+            fn [< $type:snake _ truncating >] $(< $($generic : LenseView),* >)? (self) -> ::rosenpass_lenses::LenseResult< $type<Self::__ContainerType, $( $($generic),+ )? >> {
+                let required_size = $( $len + )+ 0;
+                ::rosenpass_lenses::LenseError::ensure_sufficient_buffer_size(self.len(), required_size)?;
+                [< $type Ext >]::[< $type:snake >](&self[..required_size])
+            }
+        }
+
+        impl<'a> [< $type Ext >] for &'a mut [u8] {
+            type __ContainerType = &'a mut [u8];
+            fn [< $type:snake >] $(< $($generic : LenseView),* >)? (self) -> ::rosenpass_lenses::LenseResult< $type<Self::__ContainerType, $( $($generic),+ )? >> {
+                $type::<Self::__ContainerType, $( $($generic),+ )? >::check_size(self.len())?;
+                Ok($type ( self, $( $( ::core::marker::PhantomData::<$generic>  ),+ )? ))
+            }
+
+            fn [< $type:snake _ truncating >] $(< $($generic : LenseView),* >)? (self) -> ::rosenpass_lenses::LenseResult< $type<Self::__ContainerType, $( $($generic),+ )? >> {
+                let required_size = $( $len + )+ 0;
+                ::rosenpass_lenses::LenseError::ensure_sufficient_buffer_size(self.len(), required_size)?;
+                [< $type Ext >]::[< $type:snake >](&mut self[..required_size])
+            }
+        }
+    });
+);

oqs/Cargo.toml

@@ -0,0 +1,16 @@
+[package]
+name = "rosenpass-oqs"
+authors = ["Karolin Varner <karo@cupdev.net>", "wucke13 <wucke13@gmail.com>"]
+version = "0.1.0"
+edition = "2021"
+license = "MIT OR Apache-2.0"
+description = "Rosenpass internal bindings to liboqs"
+homepage = "https://rosenpass.eu/"
+repository = "https://github.com/rosenpass/rosenpass"
+readme = "readme.md"
+
+[dependencies]
+rosenpass-cipher-traits = { workspace = true }
+rosenpass-util = { workspace = true }
+oqs-sys = { workspace = true }
+paste = { workspace = true }

oqs/readme.md

@@ -0,0 +1,5 @@
+# Rosenpass internal liboqs bindings
+
+Rosenpass internal library providing bindings to liboqs.
+
+This is an internal library; not guarantee is made about its API at this point in time.

oqs/src/kem_macro.rs

@@ -0,0 +1,80 @@
+macro_rules! oqs_kem {
+    ($name:ident) => { ::paste::paste!{
+        mod [< $name:snake >] {
+            use rosenpass_cipher_traits::Kem;
+            use rosenpass_util::result::Guaranteed;
+
+            pub enum [< $name:camel >]  {}
+
+            /// # Panic & Safety
+            ///
+            /// This Trait impl calls unsafe [oqs_sys] functions, that write to byte
+            /// slices only identified using raw pointers. It must be ensured that the raw
+            /// pointers point into byte slices of sufficient length, to avoid UB through
+            /// overwriting of arbitrary data. This is ensured through assertions in the
+            /// implementation.
+            ///
+            /// __Note__: This requirement is stricter than necessary, it would suffice
+            /// to only check that the buffers are big enough, allowing them to be even
+            /// bigger. However, from a correctness point of view it does not make sense to
+            /// allow bigger buffers.
+            impl Kem for [< $name:camel >] {
+                type Error = ::std::convert::Infallible;
+
+                const SK_LEN: usize =  ::oqs_sys::kem::[<OQS_KEM _ $name:snake _ length_secret_key >] as usize;
+                const PK_LEN: usize =  ::oqs_sys::kem::[<OQS_KEM _ $name:snake _ length_public_key >] as usize;
+                const CT_LEN: usize =  ::oqs_sys::kem::[<OQS_KEM _ $name:snake _ length_ciphertext >] as usize;
+                const SHK_LEN: usize =  ::oqs_sys::kem::[<OQS_KEM _ $name:snake _ length_shared_secret >] as usize;
+
+                fn keygen(sk: &mut [u8], pk: &mut [u8]) -> Guaranteed<()> {
+                    assert_eq!(sk.len(), Self::SK_LEN);
+                    assert_eq!(pk.len(), Self::PK_LEN);
+                    unsafe {
+                        oqs_call!(
+                            ::oqs_sys::kem::[< OQS_KEM _ $name:snake _ keypair >],
+                            pk.as_mut_ptr(),
+                            sk.as_mut_ptr()
+                        );
+                    }
+
+                    Ok(())
+                }
+
+                fn encaps(shk: &mut [u8], ct: &mut [u8], pk: &[u8]) -> Guaranteed<()> {
+                    assert_eq!(shk.len(), Self::SHK_LEN);
+                    assert_eq!(ct.len(), Self::CT_LEN);
+                    assert_eq!(pk.len(), Self::PK_LEN);
+                    unsafe {
+                        oqs_call!(
+                            ::oqs_sys::kem::[< OQS_KEM _ $name:snake _ encaps >],
+                            ct.as_mut_ptr(),
+                            shk.as_mut_ptr(),
+                            pk.as_ptr()
+                        );
+                    }
+
+                    Ok(())
+                }
+
+                fn decaps(shk: &mut [u8], sk: &[u8], ct: &[u8]) -> Guaranteed<()> {
+                    assert_eq!(shk.len(), Self::SHK_LEN);
+                    assert_eq!(sk.len(), Self::SK_LEN);
+                    assert_eq!(ct.len(), Self::CT_LEN);
+                    unsafe {
+                        oqs_call!(
+                            ::oqs_sys::kem::[< OQS_KEM _ $name:snake _ decaps >],
+                            shk.as_mut_ptr(),
+                            ct.as_ptr(),
+                            sk.as_ptr()
+                        );
+                    }
+
+                    Ok(())
+                }
+            }
+
+        }
+
+        pub use [< $name:snake >] :: [< $name:camel >];
+    }}
+}

oqs/src/lib.rs

@@ -0,0 +1,21 @@
+macro_rules! oqs_call {
+    ($name:path, $($args:expr),*) => {{
+        use oqs_sys::common::OQS_STATUS::*;
+
+        match $name($($args),*) {
+            OQS_SUCCESS => {}, // nop
+            OQS_EXTERNAL_LIB_ERROR_OPENSSL => {
+                panic!("OpenSSL error in liboqs' {}.", stringify!($name));
+            },
+            OQS_ERROR => {
+                panic!("Unknown error in liboqs' {}.", stringify!($name));
+            }
+        }
+    }};
+    ($name:ident) => { oqs_call!($name, ) };
+}
+
+#[macro_use]
+mod kem_macro;
+oqs_kem!(kyber_512);
+oqs_kem!(classic_mceliece_460896);

papers/tex/template-rosenpass.tex

@@ -177,7 +177,11 @@ version={4.0},
 		\titlehead{\centerline{\includegraphics[width=4cm]{RosenPass-Logo}}}
 		\title{\inserttitle}
 	}
-	\author{\csname insertauthor\endcsname}
+	\ifx\csname insertauthor\endcsname\relax
+	\author{}
+	\else
+	\author{\parbox{\linewidth}{\centering\insertauthor}}
+	\fi
 	\subject{\csname insertsubject\endcsname}
 	\date{\vspace{-1cm}}
 }

rosenpass/Cargo.toml

@@ -1,10 +1,10 @@
 [package]
 name = "rosenpass"
+description = "Build post-quantum-secure VPNs with WireGuard!"
 version = "0.2.1"
 authors = ["Karolin Varner <karo@cupdev.net>", "wucke13 <wucke13@gmail.com>"]
 edition = "2021"
 license = "MIT OR Apache-2.0"
-description = "Build post-quantum-secure VPNs with WireGuard!"
 homepage = "https://rosenpass.eu/"
 repository = "https://github.com/rosenpass/rosenpass"
 readme = "readme.md"
@@ -16,15 +16,15 @@ harness = false
 [dependencies]
 rosenpass-util = { workspace = true }
 rosenpass-constant-time = { workspace = true }
-rosenpass-sodium = { workspace = true }
 rosenpass-ciphers = { workspace = true }
+rosenpass-cipher-traits = { workspace = true }
 rosenpass-to = { workspace = true }
+rosenpass-secret-memory = { workspace = true }
+rosenpass-lenses = { workspace = true }
+rosenpass-wireguard-broker = { workspace = true }
 anyhow = { workspace = true }
 static_assertions = { workspace = true }
 memoffset = { workspace = true }
-libsodium-sys-stable = { workspace = true }
-oqs-sys = { workspace = true }
-lazy_static = { workspace = true }
 thiserror = { workspace = true }
 paste = { workspace = true }
 log = { workspace = true }
@@ -33,6 +33,10 @@ serde = { workspace = true }
 toml = { workspace = true }
 clap = { workspace = true }
 mio = { workspace = true }
+rand = { workspace = true }
+
+[target.'cfg(target_os = "hermit")'.dependencies]
+hermit = { version = "0.8", features = ["pci", "pci-ids", "acpi", "fsgsbase", "tcp", "rtl8139"]}
 
 [build-dependencies]
 anyhow = { workspace = true }

rosenpass/benches/handshake.rs

@@ -1,10 +1,8 @@
 use anyhow::Result;
-use rosenpass::pqkem::KEM;
-use rosenpass::{
-    pqkem::StaticKEM,
-    protocol::{CryptoServer, HandleMsgResult, MsgBuf, PeerPtr, SPk, SSk, SymKey},
-    sodium::sodium_init,
-};
+use rosenpass::protocol::{CryptoServer, HandleMsgResult, MsgBuf, PeerPtr, SPk, SSk, SymKey};
+
+use rosenpass_cipher_traits::Kem;
+use rosenpass_ciphers::kem::StaticKem;
 
 use criterion::{black_box, criterion_group, criterion_main, Criterion};
 
@@ -41,7 +39,7 @@ fn hs(ini: &mut CryptoServer, res: &mut CryptoServer) -> Result<()> {
 
 fn keygen() -> Result<(SSk, SPk)> {
     let (mut sk, mut pk) = (SSk::zero(), SPk::zero());
-    StaticKEM::keygen(sk.secret_mut(), pk.secret_mut())?;
+    StaticKem::keygen(sk.secret_mut(), pk.secret_mut())?;
     Ok((sk, pk))
 }
 
@@ -58,7 +56,6 @@ fn make_server_pair() -> Result<(CryptoServer, CryptoServer)> {
 }
 
 fn criterion_benchmark(c: &mut Criterion) {
-    sodium_init().unwrap();
     let (mut a, mut b) = make_server_pair().unwrap();
     c.bench_function("cca_secret_alloc", |bench| {
         bench.iter(|| {

rosenpass/src/app_server.rs

@@ -1,38 +1,25 @@
-use anyhow::bail;
-
-use anyhow::Result;
-use log::{debug, error, info, warn};
-use mio::Interest;
-use mio::Token;
-use rosenpass_util::file::fopen_w;
-
-use std::cell::Cell;
-use std::io::Write;
-
-use std::io::ErrorKind;
-use std::net::Ipv4Addr;
-use std::net::Ipv6Addr;
-use std::net::SocketAddr;
-use std::net::SocketAddrV4;
-use std::net::SocketAddrV6;
-use std::net::ToSocketAddrs;
+use std::cell::{Cell, RefCell};
+use std::io::{ErrorKind, Write};
+use std::net::{Ipv4Addr, Ipv6Addr, SocketAddr, SocketAddrV4, SocketAddrV6, ToSocketAddrs, TcpStream};
 use std::path::PathBuf;
-use std::process::Command;
-use std::process::Stdio;
 use std::slice;
-use std::thread;
 use std::time::Duration;
 
-use crate::{
-    config::Verbosity,
-    protocol::{CryptoServer, MsgBuf, PeerPtr, SPk, SSk, SymKey, Timing},
-};
-use rosenpass_util::attempt;
+use anyhow::{bail, Result};
+use log::{error, info, warn};
+use mio::{Interest, Token};
+
+use rosenpass_secret_memory::Public;
 use rosenpass_util::b64::{b64_writer, fmt_b64};
+use rosenpass_util::{attempt, file::fopen_w};
+use rosenpass_wireguard_broker::api::mio_client::MioBrokerClient as PskBroker;
+use rosenpass_wireguard_broker::WireGuardBroker;
+
+use crate::config::Verbosity;
+use crate::protocol::{CryptoServer, MsgBuf, PeerPtr, SPk, SSk, SymKey, Timing};
 
 const IPV4_ANY_ADDR: Ipv4Addr = Ipv4Addr::new(0, 0, 0, 0);
 const IPV6_ANY_ADDR: Ipv6Addr = Ipv6Addr::new(0, 0, 0, 0, 0, 0, 0, 0);
-
 fn ipv4_any_binding() -> SocketAddr {
     // addr, port
     SocketAddr::V4(SocketAddrV4::new(IPV4_ANY_ADDR, 0))
@@ -43,6 +30,19 @@ fn ipv6_any_binding() -> SocketAddr {
     SocketAddr::V6(SocketAddrV6::new(IPV6_ANY_ADDR, 0, 0, 0))
 }
 
+#[derive(Default)]
+struct MioTokenDispenser {
+    counter: usize,
+}
+
+impl MioTokenDispenser {
+    fn get_token(&mut self) -> Token {
+        let r = self.counter;
+        self.counter += 1;
+        Token(r)
+    }
+}
+
 #[derive(Default, Debug)]
 pub struct AppPeer {
     pub outfile: Option<PathBuf>,
@@ -59,14 +59,24 @@ impl AppPeer {
     }
 }
 
-#[derive(Default, Debug)]
+#[derive(Debug)]
 pub struct WireguardOut {
     // impl KeyOutput
     pub dev: String,
-    pub pk: String,
+    pub pk: Public<32>,
     pub extra_params: Vec<String>,
 }
 
+impl Default for WireguardOut {
+    fn default() -> Self {
+        Self {
+            dev: Default::default(),
+            pk: Public::zero(),
+            extra_params: Default::default(),
+        }
+    }
+}
+
 /// Holds the state of the application, namely the external IO
 ///
 /// Responsible for file IO, network IO
@@ -77,6 +87,7 @@ pub struct AppServer {
     pub sockets: Vec<mio::net::UdpSocket>,
     pub events: mio::Events,
     pub mio_poll: mio::Poll,
+    pub psk_broker: RefCell<PskBroker>,
     pub peers: Vec<AppPeer>,
     pub verbosity: Verbosity,
     pub all_sockets_drained: bool,
@@ -341,11 +352,24 @@ impl AppServer {
         sk: SSk,
         pk: SPk,
         addrs: Vec<SocketAddr>,
+        psk_broker_socket: TcpStream,
         verbosity: Verbosity,
     ) -> anyhow::Result<Self> {
         // setup mio
         let mio_poll = mio::Poll::new()?;
         let events = mio::Events::with_capacity(8);
+        let mut dispenser = MioTokenDispenser::default();
+
+        // Create the Wireguard broker connection
+        let psk_broker = {
+            let mut sock = mio::net::TcpStream::from_std(psk_broker_socket);
+            mio_poll.registry().register(
+                &mut sock,
+                dispenser.get_token(),
+                Interest::READABLE | Interest::WRITABLE,
+            )?;
+            PskBroker::new(sock)
+        };
 
         // bind each SocketAddr to a socket
         let maybe_sockets: Result<Vec<_>, _> =
@@ -430,6 +454,7 @@ impl AppServer {
         Ok(Self {
             crypt: CryptoServer::new(sk, pk),
             peers: Vec::new(),
+            psk_broker: RefCell::new(psk_broker),
             verbosity,
             sockets,
             events,
@@ -624,31 +649,9 @@ impl AppServer {
         }
 
         if let Some(owg) = ap.outwg.as_ref() {
-            let mut child = Command::new("wg")
-                .arg("set")
-                .arg(&owg.dev)
-                .arg("peer")
-                .arg(&owg.pk)
-                .arg("preshared-key")
-                .arg("/dev/stdin")
-                .stdin(Stdio::piped())
-                .args(&owg.extra_params)
-                .spawn()?;
-            b64_writer(child.stdin.take().unwrap()).write_all(key.secret())?;
-
-            thread::spawn(move || {
-                let status = child.wait();
-
-                if let Ok(status) = status {
-                    if status.success() {
-                        debug!("successfully passed psk to wg")
-                    } else {
-                        error!("could not pass psk to wg {:?}", status)
-                    }
-                } else {
-                    error!("wait failed: {:?}", status)
-                }
-            });
+            self.psk_broker
+                .borrow_mut()
+                .set_psk(&owg.dev, owg.pk.value, *key.secret())?;
         }
 
         Ok(())
@@ -706,9 +709,16 @@ impl AppServer {
 
         // only poll if we drained all sockets before
         if self.all_sockets_drained {
-            self.mio_poll.poll(&mut self.events, Some(timeout))?;
+            self.mio_poll
+                .poll(&mut self.events, Some(timeout))
+                .or_else(|e| match e.kind() {
+                    ErrorKind::Interrupted | ErrorKind::WouldBlock => Ok(()),
+                    _ => Err(e),
+                })?;
         }
 
+        self.psk_broker.get_mut().poll()?;
+
         let mut would_block_count = 0;
         for (sock_no, socket) in self.sockets.iter_mut().enumerate() {
             match socket.recv_from(buf) {

rosenpass/src/cli.rs

@@ -1,16 +1,20 @@
-use anyhow::{bail, ensure};
+use std::io::{BufReader, Read};
+use std::net::TcpStream;
+use std::path::PathBuf;
+
+use anyhow::{bail, ensure, Context};
 use clap::Parser;
+
+use rosenpass_cipher_traits::Kem;
+use rosenpass_ciphers::kem::StaticKem;
+use rosenpass_secret_memory::file::StoreSecret;
+use rosenpass_secret_memory::Public;
+use rosenpass_util::b64::b64_reader;
 use rosenpass_util::file::{LoadValue, LoadValueB64};
-use std::path::{Path, PathBuf};
 
 use crate::app_server;
 use crate::app_server::AppServer;
-use crate::{
-    // app_server::{AppServer, LoadValue, LoadValueB64},
-    coloring::Secret,
-    pqkem::{StaticKEM, KEM},
-    protocol::{SPk, SSk, SymKey},
-};
+use crate::protocol::{SPk, SSk, SymKey};
 
 use super::config;
 
@@ -64,6 +68,7 @@ pub enum Cli {
         config_file: PathBuf,
 
         /// Forcefully overwrite existing config file
+        /// - [ ] Janepie
         #[clap(short, long)]
         force: bool,
     },
@@ -89,6 +94,15 @@ pub enum Cli {
         force: bool,
     },
 
+    /// Deprecated - use gen-keys instead
+    #[allow(rustdoc::broken_intra_doc_links)]
+    #[allow(rustdoc::invalid_html_tags)]
+    Keygen {
+        // NOTE yes, the legacy keygen argument initially really accepted "privet-key", not "secret-key"!
+        /// public-key <PATH> private-key <PATH>
+        args: Vec<String>,
+    },
+
     /// Validate a configuration
     Validate { config_files: Vec<PathBuf> },
 
@@ -121,6 +135,40 @@ impl Cli {
                 config::Rosenpass::example_config().store(config_file)?;
             }
 
+            // Deprecated - use gen-keys instead
+            Keygen { args } => {
+                log::warn!("The 'keygen' command is deprecated. Please use the 'gen-keys' command instead.");
+
+                let mut public_key: Option<PathBuf> = None;
+                let mut secret_key: Option<PathBuf> = None;
+
+                // Manual arg parsing, since clap wants to prefix flags with "--"
+                let mut args = args.into_iter();
+                loop {
+                    match (args.next().as_deref(), args.next()) {
+                        (Some("private-key"), Some(opt)) | (Some("secret-key"), Some(opt)) => {
+                            secret_key = Some(opt.into());
+                        }
+                        (Some("public-key"), Some(opt)) => {
+                            public_key = Some(opt.into());
+                        }
+                        (Some(flag), _) => {
+                            bail!("Unknown option `{}`", flag);
+                        }
+                        (_, _) => break,
+                    };
+                }
+
+                if secret_key.is_none() {
+                    bail!("private-key is required");
+                }
+                if public_key.is_none() {
+                    bail!("public-key is required");
+                }
+
+                generate_and_save_keypair(secret_key.unwrap(), public_key.unwrap())?;
+            }
+
             GenKeys {
                 config_file,
                 public_key,
@@ -162,12 +210,7 @@ impl Cli {
                 }
 
                 // generate the keys and store them in files
-                let mut ssk = crate::protocol::SSk::random();
-                let mut spk = crate::protocol::SPk::random();
-                StaticKEM::keygen(ssk.secret_mut(), spk.secret_mut())?;
-
-                ssk.store_secret(skf)?;
-                spk.store_secret(pkf)?;
+                generate_and_save_keypair(skf, pkf)?;
             }
 
             ExchangeConfig { config_file } => {
@@ -222,11 +265,14 @@ impl Cli {
         let sk = SSk::load(&config.secret_key)?;
         let pk = SPk::load(&config.public_key)?;
 
+        // Spawn the psk broker and use socketpair(2) to connect with them
+        let psk_broker_socket = TcpStream::connect("127.0.0.1:8001")?;
         // start an application server
         let mut srv = std::boxed::Box::<AppServer>::new(AppServer::new(
             sk,
             pk,
             config.listen,
+            psk_broker_socket,
             config.verbosity,
         )?);
 
@@ -236,11 +282,24 @@ impl Cli {
                 cfg_peer.pre_shared_key.map(SymKey::load_b64).transpose()?,
                 SPk::load(&cfg_peer.public_key)?,
                 cfg_peer.key_out,
-                cfg_peer.wg.map(|cfg| app_server::WireguardOut {
-                    dev: cfg.device,
-                    pk: cfg.peer,
-                    extra_params: cfg.extra_params,
-                }),
+                cfg_peer
+                    .wg
+                    .map(|cfg| -> anyhow::Result<_> {
+                        let b64pk = &cfg.peer;
+                        let mut pk = Public::zero();
+                        b64_reader(BufReader::new(b64pk.as_bytes()))
+                            .read_exact(&mut pk.value)
+                            .with_context(|| {
+                                format!("Could not decode base64 public key: '{b64pk}'")
+                            })?;
+
+                        Ok(app_server::WireguardOut {
+                            pk,
+                            dev: cfg.device,
+                            extra_params: cfg.extra_params,
+                        })
+                    })
+                    .transpose()?,
                 cfg_peer.endpoint.clone(),
             )?;
         }
@@ -249,13 +308,11 @@ impl Cli {
     }
 }
 
-trait StoreSecret {
-    fn store_secret<P: AsRef<Path>>(&self, path: P) -> anyhow::Result<()>;
-}
-
-impl<const N: usize> StoreSecret for Secret<N> {
-    fn store_secret<P: AsRef<Path>>(&self, path: P) -> anyhow::Result<()> {
-        std::fs::write(path, self.secret())?;
-        Ok(())
-    }
+/// generate secret and public keys, store in files according to the paths passed as arguments
+fn generate_and_save_keypair(secret_key: PathBuf, public_key: PathBuf) -> anyhow::Result<()> {
+    let mut ssk = crate::protocol::SSk::random();
+    let mut spk = crate::protocol::SPk::random();
+    StaticKem::keygen(ssk.secret_mut(), spk.secret_mut())?;
+    ssk.store_secret(secret_key)?;
+    spk.store_secret(public_key)
 }

rosenpass/src/coloring.rs

@@ -1,443 +0,0 @@
-//! Types types for dealing with (secret-) values
-//!
-//! These types use type level coloring to make accidential leackage of secrets extra hard. Both [Secret] and [Public] own their data, but the memory backing
-//! [Secret] is special:
-//! - as it is heap allocated, we can actively zeroize the memory before freeing it.
-//! - guard pages before and after each allocation trap accidential sequential reads that creep towards our secrets
-//! - the memory is mlocked, e.g. it is never swapped
-
-use anyhow::Context;
-use lazy_static::lazy_static;
-use libsodium_sys as libsodium;
-use rosenpass_util::{
-    b64::b64_reader,
-    file::{fopen_r, LoadValue, LoadValueB64, ReadExactToEnd, StoreValue},
-    functional::mutating,
-    mem::cpy,
-};
-use std::result::Result;
-use std::{
-    collections::HashMap,
-    convert::TryInto,
-    fmt,
-    ops::{Deref, DerefMut},
-    os::raw::c_void,
-    path::Path,
-    ptr::null_mut,
-    sync::Mutex,
-};
-
-// This might become a problem in library usage; it's effectively a memory
-// leak which probably isn't a problem right now because most memory will
-// be reused…
-lazy_static! {
-    static ref SECRET_CACHE: Mutex<SecretMemoryPool> = Mutex::new(SecretMemoryPool::new());
-}
-
-/// Pool that stores secret memory allocations
-///
-/// Allocation of secret memory is expensive. Thus, this struct provides a
-/// pool of secret memory, readily available to yield protected, slices of
-/// memory.
-///
-/// Further information about the protection in place can be found in in the
-/// [libsodium documentation](https://libsodium.gitbook.io/doc/memory_management#guarded-heap-allocations)
-#[derive(Debug)] // TODO check on Debug derive, is that clever
-pub struct SecretMemoryPool {
-    pool: HashMap<usize, Vec<*mut c_void>>,
-}
-
-impl SecretMemoryPool {
-    /// Create a new [SecretMemoryPool]
-    #[allow(clippy::new_without_default)]
-    pub fn new() -> Self {
-        let pool = HashMap::new();
-
-        Self { pool }
-    }
-
-    /// Return secrete back to the pool for future re-use
-    ///
-    /// This consumes the [Secret], but its memory is re-used.
-    pub fn release<const N: usize>(&mut self, mut s: Secret<N>) {
-        unsafe {
-            self.release_by_ref(&mut s);
-        }
-        std::mem::forget(s);
-    }
-
-    /// Return secret back to the pool for future re-use, by slice
-    ///
-    /// # Safety
-    ///
-    /// After calling this function on a [Secret], the secret must never be
-    /// used again for anything.
-    unsafe fn release_by_ref<const N: usize>(&mut self, s: &mut Secret<N>) {
-        s.zeroize();
-        let Secret { ptr: secret } = s;
-        // don't call Secret::drop, that could cause a double free
-        self.pool.entry(N).or_default().push(*secret);
-    }
-
-    /// Take protected memory from the pool, allocating new one if no suitable
-    /// chunk is found in the inventory.
-    ///
-    /// The secret is guaranteed to be full of nullbytes
-    ///
-    /// # Safety
-    ///
-    /// This function contains an unsafe call to [libsodium::sodium_malloc].
-    /// This call has no known safety invariants, thus nothing can go wrong™.
-    /// However, just like normal `malloc()` this can return a null ptr. Thus
-    /// the returned pointer is checked for null; causing the program to panic
-    /// if it is null.
-    pub fn take<const N: usize>(&mut self) -> Secret<N> {
-        let entry = self.pool.entry(N).or_default();
-        let secret = entry.pop().unwrap_or_else(|| {
-            let ptr = unsafe { libsodium::sodium_malloc(N) };
-            assert!(
-                !ptr.is_null(),
-                "libsodium::sodium_mallloc() returned a null ptr"
-            );
-            ptr
-        });
-
-        let mut s = Secret { ptr: secret };
-        s.zeroize();
-        s
-    }
-}
-
-impl Drop for SecretMemoryPool {
-    /// # Safety
-    ///
-    /// The drop implementation frees the contained elements using
-    /// [libsodium::sodium_free]. This is safe as long as every `*mut c_void`
-    /// contained was initialized with a call to [libsodium::sodium_malloc]
-    fn drop(&mut self) {
-        for ptr in self.pool.drain().flat_map(|(_, x)| x.into_iter()) {
-            unsafe {
-                libsodium::sodium_free(ptr);
-            }
-        }
-    }
-}
-
-/// # Safety
-///
-/// No safety implications are known, since the `*mut c_void` in
-/// is essentially used like a `&mut u8` [SecretMemoryPool].
-unsafe impl Send for SecretMemoryPool {}
-
-/// Store for a secret
-///
-/// Uses memory allocated with [libsodium::sodium_malloc],
-/// esentially can do the same things as `[u8; N].as_mut_ptr()`.
-pub struct Secret<const N: usize> {
-    ptr: *mut c_void,
-}
-
-impl<const N: usize> Clone for Secret<N> {
-    fn clone(&self) -> Self {
-        let mut new = Self::zero();
-        new.secret_mut().clone_from_slice(self.secret());
-        new
-    }
-}
-
-impl<const N: usize> Drop for Secret<N> {
-    fn drop(&mut self) {
-        self.zeroize();
-        // the invariant that the [Secret] is not used after the
-        // `release_by_ref` call is guaranteed, since this is a drop implementation
-        unsafe { SECRET_CACHE.lock().unwrap().release_by_ref(self) };
-        self.ptr = null_mut();
-    }
-}
-
-impl<const N: usize> Secret<N> {
-    pub fn from_slice(slice: &[u8]) -> Self {
-        let mut new_self = Self::zero();
-        new_self.secret_mut().copy_from_slice(slice);
-        new_self
-    }
-
-    /// Returns a new [Secret] that is zero initialized
-    pub fn zero() -> Self {
-        // Using [SecretMemoryPool] here because this operation is expensive,
-        // yet it is used in hot loops
-        let s = SECRET_CACHE.lock().unwrap().take();
-        assert_eq!(s.secret(), &[0u8; N]);
-        s
-    }
-
-    /// Returns a new [Secret] that is randomized
-    pub fn random() -> Self {
-        mutating(Self::zero(), |r| r.randomize())
-    }
-
-    /// Sets all data of an existing secret to null bytes
-    pub fn zeroize(&mut self) {
-        rosenpass_sodium::helpers::memzero(self.secret_mut());
-    }
-
-    /// Sets all data an existing secret to random bytes
-    pub fn randomize(&mut self) {
-        rosenpass_sodium::helpers::randombytes_buf(self.secret_mut());
-    }
-
-    /// Borrows the data
-    pub fn secret(&self) -> &[u8; N] {
-        // - calling `from_raw_parts` is safe, because `ptr` is initalized with
-        //   as `N` byte allocation from the creation of `Secret` onwards. `ptr`
-        //   stays valid over the full lifetime of `Secret`
-        //
-        // - calling uwnrap is safe, because we can guarantee that the slice has
-        //   exactly the required size `N` to create an array of `N` elements.
-        let ptr = self.ptr as *const u8;
-        let slice = unsafe { std::slice::from_raw_parts(ptr, N) };
-        slice.try_into().unwrap()
-    }
-
-    /// Borrows the data mutably
-    pub fn secret_mut(&mut self) -> &mut [u8; N] {
-        // the same safety argument as for `secret()` holds
-        let ptr = self.ptr as *mut u8;
-        let slice = unsafe { std::slice::from_raw_parts_mut(ptr, N) };
-        slice.try_into().unwrap()
-    }
-}
-
-/// The Debug implementation of [Secret] does not reveal the secret data,
-/// instead a placeholder `<SECRET>` is used
-impl<const N: usize> fmt::Debug for Secret<N> {
-    fn fmt(&self, fmt: &mut fmt::Formatter) -> fmt::Result {
-        fmt.write_str("<SECRET>")
-    }
-}
-
-/// Contains information in the form of a byte array that may be known to the
-/// public
-// TODO: We should get rid of the Public type; just use a normal value
-#[derive(Copy, Clone, Hash, PartialEq, Eq, PartialOrd, Ord)]
-#[repr(transparent)]
-pub struct Public<const N: usize> {
-    pub value: [u8; N],
-}
-
-impl<const N: usize> Public<N> {
-    /// Create a new [Public] from a byte slice
-    pub fn from_slice(value: &[u8]) -> Self {
-        mutating(Self::zero(), |r| cpy(value, &mut r.value))
-    }
-
-    /// Create a new [Public] from a byte array
-    pub fn new(value: [u8; N]) -> Self {
-        Self { value }
-    }
-
-    /// Create a zero initialized [Public]
-    pub fn zero() -> Self {
-        Self { value: [0u8; N] }
-    }
-
-    /// Create a random initialized [Public]
-    pub fn random() -> Self {
-        mutating(Self::zero(), |r| r.randomize())
-    }
-
-    /// Randomize all bytes in an existing [Public]
-    pub fn randomize(&mut self) {
-        rosenpass_sodium::helpers::randombytes_buf(&mut self.value);
-    }
-}
-
-/// Writes the contents of an `&[u8]` as hexadecimal symbols to a [std::fmt::Formatter]
-pub fn debug_crypto_array(v: &[u8], fmt: &mut fmt::Formatter) -> fmt::Result {
-    fmt.write_str("[{}]=")?;
-    if v.len() > 64 {
-        for byte in &v[..32] {
-            std::fmt::LowerHex::fmt(byte, fmt)?;
-        }
-        fmt.write_str("…")?;
-        for byte in &v[v.len() - 32..] {
-            std::fmt::LowerHex::fmt(byte, fmt)?;
-        }
-    } else {
-        for byte in v {
-            std::fmt::LowerHex::fmt(byte, fmt)?;
-        }
-    }
-    Ok(())
-}
-
-impl<const N: usize> fmt::Debug for Public<N> {
-    fn fmt(&self, fmt: &mut fmt::Formatter) -> fmt::Result {
-        debug_crypto_array(&self.value, fmt)
-    }
-}
-
-impl<const N: usize> Deref for Public<N> {
-    type Target = [u8; N];
-
-    fn deref(&self) -> &[u8; N] {
-        &self.value
-    }
-}
-
-impl<const N: usize> DerefMut for Public<N> {
-    fn deref_mut(&mut self) -> &mut [u8; N] {
-        &mut self.value
-    }
-}
-
-#[cfg(test)]
-mod test {
-    use super::*;
-
-    /// https://libsodium.gitbook.io/doc/memory_management#guarded-heap-allocations
-    /// promises us that allocated memory is initialized with this magic byte
-    const SODIUM_MAGIC_BYTE: u8 = 0xdb;
-
-    /// must be called before any interaction with libsodium
-    fn init() {
-        unsafe { libsodium_sys::sodium_init() };
-    }
-
-    /// checks that whe can malloc with libsodium
-    #[test]
-    fn sodium_malloc() {
-        init();
-        const N: usize = 8;
-        let ptr = unsafe { libsodium_sys::sodium_malloc(N) };
-        let mem = unsafe { std::slice::from_raw_parts(ptr as *mut u8, N) };
-        assert_eq!(mem, &[SODIUM_MAGIC_BYTE; N])
-    }
-
-    /// checks that whe can free with libsodium
-    #[test]
-    fn sodium_free() {
-        init();
-        const N: usize = 8;
-        let ptr = unsafe { libsodium_sys::sodium_malloc(N) };
-        unsafe { libsodium_sys::sodium_free(ptr) }
-    }
-
-    /// check that we can alloc using the magic pool
-    #[test]
-    fn secret_memory_pool_take() {
-        init();
-        const N: usize = 0x100;
-        let mut pool = SecretMemoryPool::new();
-        let secret: Secret<N> = pool.take();
-        assert_eq!(secret.secret(), &[0; N]);
-    }
-
-    /// check that a secrete lives, even if its [SecretMemoryPool] is deleted
-    #[test]
-    fn secret_memory_pool_drop() {
-        init();
-        const N: usize = 0x100;
-        let mut pool = SecretMemoryPool::new();
-        let secret: Secret<N> = pool.take();
-        std::mem::drop(pool);
-        assert_eq!(secret.secret(), &[0; N]);
-    }
-
-    /// check that a secrete can be reborn, freshly initialized with zero
-    #[test]
-    fn secret_memory_pool_release() {
-        init();
-        const N: usize = 1;
-        let mut pool = SecretMemoryPool::new();
-        let mut secret: Secret<N> = pool.take();
-        let old_secret_ptr = secret.ptr;
-
-        secret.secret_mut()[0] = 0x13;
-        pool.release(secret);
-
-        // now check that we get the same ptr
-        let new_secret: Secret<N> = pool.take();
-        assert_eq!(old_secret_ptr, new_secret.ptr);
-
-        // and that the secret was zeroized
-        assert_eq!(new_secret.secret(), &[0; N]);
-    }
-}
-
-trait StoreSecret {
-    type Error;
-
-    fn store_secret<P: AsRef<Path>>(&self, path: P) -> Result<(), Self::Error>;
-}
-
-impl<T: StoreValue> StoreSecret for T {
-    type Error = <T as StoreValue>::Error;
-
-    fn store_secret<P: AsRef<Path>>(&self, path: P) -> Result<(), Self::Error> {
-        self.store(path)
-    }
-}
-
-impl<const N: usize> LoadValue for Secret<N> {
-    type Error = anyhow::Error;
-
-    fn load<P: AsRef<Path>>(path: P) -> anyhow::Result<Self> {
-        let mut v = Self::random();
-        let p = path.as_ref();
-        fopen_r(p)?
-            .read_exact_to_end(v.secret_mut())
-            .with_context(|| format!("Could not load file {p:?}"))?;
-        Ok(v)
-    }
-}
-
-impl<const N: usize> LoadValueB64 for Secret<N> {
-    type Error = anyhow::Error;
-
-    fn load_b64<P: AsRef<Path>>(path: P) -> anyhow::Result<Self> {
-        use std::io::Read;
-
-        let mut v = Self::random();
-        let p = path.as_ref();
-        // This might leave some fragments of the secret on the stack;
-        // in practice this is likely not a problem because the stack likely
-        // will be overwritten by something else soon but this is not exactly
-        // guaranteed. It would be possible to remedy this, but since the secret
-        // data will linger in the Linux page cache anyways with the current
-        // implementation, going to great length to erase the secret here is
-        // not worth it right now.
-        b64_reader(&mut fopen_r(p)?)
-            .read_exact(v.secret_mut())
-            .with_context(|| format!("Could not load base64 file {p:?}"))?;
-        Ok(v)
-    }
-}
-
-impl<const N: usize> StoreSecret for Secret<N> {
-    type Error = anyhow::Error;
-
-    fn store_secret<P: AsRef<Path>>(&self, path: P) -> anyhow::Result<()> {
-        std::fs::write(path, self.secret())?;
-        Ok(())
-    }
-}
-
-impl<const N: usize> LoadValue for Public<N> {
-    type Error = anyhow::Error;
-
-    fn load<P: AsRef<Path>>(path: P) -> anyhow::Result<Self> {
-        let mut v = Self::random();
-        fopen_r(path)?.read_exact_to_end(&mut *v)?;
-        Ok(v)
-    }
-}
-
-impl<const N: usize> StoreValue for Public<N> {
-    type Error = anyhow::Error;
-
-    fn store<P: AsRef<Path>>(&self, path: P) -> anyhow::Result<()> {
-        std::fs::write(path, **self)?;
-        Ok(())
-    }
-}

rosenpass/src/config.rs

@@ -41,10 +41,6 @@ pub struct RosenpassPeer {
     #[serde(default)]
     pub key_out: Option<PathBuf>,
 
-    // TODO make sure failure does not crash but is logged
-    #[serde(default)]
-    pub exchange_command: Vec<String>,
-
     // TODO make this field only available on binary builds, not on library builds
     #[serde(flatten)]
     pub wg: Option<WireGuard>,
@@ -345,28 +341,20 @@ impl Rosenpass {
     /// Generate an example configuration
     pub fn example_config() -> Self {
         let peer = RosenpassPeer {
-            public_key: "rp-peer-public-key".into(),
+            public_key: "/path/to/rp-peer-public-key".into(),
             endpoint: Some("my-peer.test:9999".into()),
-            exchange_command: [
-                "wg",
-                "set",
-                "wg0",
-                "peer",
-                "<PEER_ID>",
-                "preshared-key",
-                "/dev/stdin",
-            ]
-            .into_iter()
-            .map(|x| x.to_string())
-            .collect(),
-            key_out: Some("rp-key-out".into()),
-            pre_shared_key: None,
-            wg: None,
+            key_out: Some("/path/to/rp-key-out.txt".into()),
+            pre_shared_key: Some("additional pre shared key".into()),
+            wg: Some(WireGuard {
+                device: "wirgeguard device e.g. wg0".into(),
+                peer: "wireguard public key".into(),
+                extra_params: vec!["passed to".into(), "wg set".into()],
+            }),
         };
 
         Self {
-            public_key: "rp-public-key".into(),
-            secret_key: "rp-secret-key".into(),
+            public_key: "/path/to/rp-public-key".into(),
+            secret_key: "/path/to/rp-secret-key".into(),
             peers: vec![peer],
             ..Self::new("", "")
         }
@@ -386,7 +374,7 @@ mod test {
     use super::*;
 
     fn split_str(s: &str) -> Vec<String> {
-        s.split(" ").map(|s| s.to_string()).collect()
+        s.split(' ').map(|s| s.to_string()).collect()
     }
 
     #[test]

rosenpass/src/hash_domains.rs

@@ -0,0 +1,46 @@
+//! Pseudo Random Functions (PRFs) with a tree-like label scheme which
+//! ensures their uniqueness
+
+use anyhow::Result;
+use rosenpass_ciphers::{hash_domain::HashDomain, KEY_LEN};
+
+// TODO Use labels that can serve as identifiers
+macro_rules! hash_domain_ns {
+    ($base:ident, $name:ident, $($lbl:expr),* ) => {
+        pub fn $name() -> Result<HashDomain> {
+            let t = $base()?;
+            $( let t = t.mix($lbl.as_bytes())?; )*
+            Ok(t)
+        }
+    }
+}
+
+macro_rules! hash_domain {
+    ($base:ident, $name:ident, $($lbl:expr),* ) => {
+        pub fn $name() -> Result<[u8; KEY_LEN]> {
+            let t = $base()?;
+            $( let t = t.mix($lbl.as_bytes())?; )*
+            Ok(t.into_value())
+        }
+    }
+}
+
+pub fn protocol() -> Result<HashDomain> {
+    HashDomain::zero().mix("Rosenpass v1 mceliece460896 Kyber512 ChaChaPoly1305 BLAKE2s".as_bytes())
+}
+
+hash_domain_ns!(protocol, mac, "mac");
+hash_domain_ns!(protocol, cookie, "cookie");
+hash_domain_ns!(protocol, peerid, "peer id");
+hash_domain_ns!(protocol, biscuit_ad, "biscuit additional data");
+hash_domain_ns!(protocol, ckinit, "chaining key init");
+hash_domain_ns!(protocol, _ckextract, "chaining key extract");
+
+hash_domain!(_ckextract, mix, "mix");
+hash_domain!(_ckextract, hs_enc, "handshake encryption");
+hash_domain!(_ckextract, ini_enc, "initiator handshake encryption");
+hash_domain!(_ckextract, res_enc, "responder handshake encryption");
+
+hash_domain_ns!(_ckextract, _user, "user");
+hash_domain_ns!(_user, _rp, "rosenpass.eu");
+hash_domain!(_rp, osk, "wireguard psk");

rosenpass/src/labeled_prf.rs

@@ -1,48 +0,0 @@
-//! Pseudo Random Functions (PRFs) with a tree-like label scheme which
-//! ensures their uniqueness
-
-
-use crate::prftree::PrfTree;
-use anyhow::Result;
-use rosenpass_ciphers::KEY_LEN;
-
-pub fn protocol() -> Result<PrfTree> {
-    PrfTree::zero().mix("Rosenpass v1 mceliece460896 Kyber512 ChaChaPoly1305 BLAKE2s".as_bytes())
-}
-
-// TODO Use labels that can serve as identifiers
-macro_rules! prflabel {
-    ($base:ident, $name:ident, $($lbl:expr),* ) => {
-        pub fn $name() -> Result<PrfTree> {
-            let t = $base()?;
-            $( let t = t.mix($lbl.as_bytes())?; )*
-            Ok(t)
-        }
-    }
-}
-
-prflabel!(protocol, mac, "mac");
-prflabel!(protocol, cookie, "cookie");
-prflabel!(protocol, peerid, "peer id");
-prflabel!(protocol, biscuit_ad, "biscuit additional data");
-prflabel!(protocol, ckinit, "chaining key init");
-prflabel!(protocol, _ckextract, "chaining key extract");
-
-macro_rules! prflabel_leaf {
-    ($base:ident, $name:ident, $($lbl:expr),* ) => {
-        pub fn $name() -> Result<[u8; KEY_LEN]> {
-            let t = $base()?;
-            $( let t = t.mix($lbl.as_bytes())?; )*
-            Ok(t.into_value())
-        }
-    }
-}
-
-prflabel_leaf!(_ckextract, mix, "mix");
-prflabel_leaf!(_ckextract, hs_enc, "handshake encryption");
-prflabel_leaf!(_ckextract, ini_enc, "initiator handshake encryption");
-prflabel_leaf!(_ckextract, res_enc, "responder handshake encryption");
-
-prflabel!(_ckextract, _user, "user");
-prflabel!(_user, _rp, "rosenpass.eu");
-prflabel_leaf!(_rp, osk, "wireguard psk");

rosenpass/src/lib.rs

@@ -1,56 +1,24 @@
-pub mod coloring;
-#[rustfmt::skip]
-pub mod labeled_prf;
+use rosenpass_lenses::LenseError;
+
 pub mod app_server;
 pub mod cli;
 pub mod config;
+pub mod hash_domains;
 pub mod msgs;
-pub mod pqkem;
-pub mod prftree;
 pub mod protocol;
 
 #[derive(thiserror::Error, Debug)]
 pub enum RosenpassError {
-    #[error("error in OQS")]
-    Oqs,
-    #[error("error from external library while calling OQS")]
-    OqsExternalLib,
-    #[error("buffer size mismatch, required {required_size} but found {actual_size}")]
-    BufferSizeMismatch {
-        required_size: usize,
-        actual_size: usize,
-    },
+    #[error("buffer size mismatch")]
+    BufferSizeMismatch,
     #[error("invalid message type")]
     InvalidMessageType(u8),
 }
 
-impl RosenpassError {
-    /// Helper function to check a buffer size
-    fn check_buffer_size(required_size: usize, actual_size: usize) -> Result<(), Self> {
-        if required_size != actual_size {
-            Err(Self::BufferSizeMismatch {
-                required_size,
-                actual_size,
-            })
-        } else {
-            Ok(())
-        }
-    }
-}
-
-/// Extension trait to attach function calls to foreign types.
-trait RosenpassMaybeError {
-    /// Checks whether something is an error or not
-    fn to_rg_error(&self) -> Result<(), RosenpassError>;
-}
-
-impl RosenpassMaybeError for oqs_sys::common::OQS_STATUS {
-    fn to_rg_error(&self) -> Result<(), RosenpassError> {
-        use oqs_sys::common::OQS_STATUS;
-        match self {
-            OQS_STATUS::OQS_SUCCESS => Ok(()),
-            OQS_STATUS::OQS_ERROR => Err(RosenpassError::Oqs),
-            OQS_STATUS::OQS_EXTERNAL_LIB_ERROR_OPENSSL => Err(RosenpassError::OqsExternalLib),
+impl From<LenseError> for RosenpassError {
+    fn from(value: LenseError) -> Self {
+        match value {
+            LenseError::BufferSizeMismatch => RosenpassError::BufferSizeMismatch,
         }
     }
 }

rosenpass/src/main.rs

@@ -1,18 +1,16 @@
 use log::error;
 use rosenpass::cli::Cli;
-use rosenpass_util::attempt;
 use std::process::exit;
 
+#[cfg(target_os = "hermit")]
+use hermit as _;
+
 /// Catches errors, prints them through the logger, then exits
 pub fn main() {
-    env_logger::init();
+    // default to displaying warning and error log messages only
+    env_logger::Builder::from_env(env_logger::Env::default().default_filter_or("warn")).init();
 
-    let res = attempt!({
-        rosenpass_sodium::init()?;
-        Cli::run()
-    });
-
-    match res {
+    match Cli::run() {
         Ok(_) => {}
         Err(e) => {
             error!("{e}");

rosenpass/src/msgs.rs

@@ -9,14 +9,15 @@
 //!
 //! # Example
 //!
-//! The following example uses the [`data_lense` macro](crate::data_lense) to create a lense that
+//! The following example uses the [`lense` macro](rosenpass_lenses::lense) to create a lense that
 //! might be useful when dealing with UDP headers.
 //!
 //! ```
-//! use rosenpass::{data_lense, RosenpassError, msgs::LenseView};
+//! use rosenpass_lenses::{lense, LenseView};
+//! use rosenpass::RosenpassError;
 //! # fn main() -> Result<(), RosenpassError> {
 //!
-//! data_lense! {UdpDatagramHeader :=
+//! lense! {UdpDatagramHeader :=
 //!     source_port: 2,
 //!     dest_port: 2,
 //!     length: 2,
@@ -44,219 +45,14 @@
 //! ```
 
 use super::RosenpassError;
-use crate::pqkem::*;
+use rosenpass_cipher_traits::Kem;
+use rosenpass_ciphers::kem::{EphemeralKem, StaticKem};
 use rosenpass_ciphers::{aead, xaead, KEY_LEN};
+use rosenpass_lenses::{lense, LenseView};
 
 // Macro magic ////////////////////////////////////////////////////////////////
 
-/// A macro to create data lenses. Refer to the [`msgs` mod](crate::msgs) for
-/// an example and further elaboration
-// TODO implement TryFrom<[u8]> and From<[u8; Self::len()]>
-#[macro_export]
-macro_rules! data_lense(
-    // prefix          @ offset       ; optional meta    ; field name   : field length, ...
-    (token_muncher_ref @ $offset:expr ; $( $attr:meta )* ; $field:ident : $len:expr $(, $( $tail:tt )+ )?) =>  {
-        ::paste::paste!{
-
-        #[allow(rustdoc::broken_intra_doc_links)]
-        $( #[ $attr ] )*
-        ///
-        #[doc = data_lense!(maybe_docstring_link $len)]
-        /// bytes long
-        pub fn $field(&self) -> &__ContainerType::Output {
-            &self.0[$offset .. $offset + $len]
-        }
-
-        /// The bytes until the
-        #[doc = data_lense!(maybe_docstring_link Self::$field)]
-        /// field
-        pub fn [< until_ $field >](&self) -> &__ContainerType::Output {
-            &self.0[0 .. $offset]
-        }
-
-        // if the tail exits, consume it as well
-        $(
-        data_lense!{token_muncher_ref @ $offset + $len ; $( $tail )+ }
-        )?
-        }
-    };
-
-    // prefix          @ offset       ; optional meta    ; field name   : field length, ...
-    (token_muncher_mut @ $offset:expr ; $( $attr:meta )* ; $field:ident : $len:expr $(, $( $tail:tt )+ )?) =>  {
-        ::paste::paste!{
-
-        #[allow(rustdoc::broken_intra_doc_links)]
-        $( #[ $attr ] )*
-        ///
-        #[doc = data_lense!(maybe_docstring_link $len)]
-        /// bytes long
-        pub fn [< $field _mut >](&mut self) -> &mut __ContainerType::Output {
-            &mut self.0[$offset .. $offset + $len]
-        }
-
-        // if the tail exits, consume it as well
-        $(
-        data_lense!{token_muncher_mut @ $offset + $len ; $( $tail )+ }
-        )?
-        }
-    };
-
-    // switch that yields literals unchanged, but creates docstring links to
-    // constants
-    // TODO the doc string link doesn't work if $x is taken from a generic,
-    (maybe_docstring_link $x:literal) => (stringify!($x));
-    (maybe_docstring_link $x:expr) => (stringify!([$x]));
-
-    // struct name  < optional generics     >    := optional doc string      field name   : field length, ...
-    ($type:ident $( < $( $generic:ident ),+ > )? := $( $( #[ $attr:meta ] )* $field:ident : $len:expr ),+) => (::paste::paste!{
-
-        #[allow(rustdoc::broken_intra_doc_links)]
-        /// A data lense to manipulate byte slices.
-        ///
-        //// # Fields
-        ///
-        $(
-        /// - `
-        #[doc = stringify!($field)]
-        /// `:
-        #[doc = data_lense!(maybe_docstring_link $len)]
-        /// bytes
-        )+
-        pub struct $type<__ContainerType $(, $( $generic ),+ )? > (
-            __ContainerType,
-            // The phantom data is required, since all generics declared on a
-            // type need to be used on the type.
-            // https://doc.rust-lang.org/stable/error_codes/E0392.html
-            $( $( ::core::marker::PhantomData<$generic> ),+ )?
-        );
-
-        impl<__ContainerType $(, $( $generic: LenseView ),+ )? > $type<__ContainerType $(, $( $generic ),+ )? >{
-            $(
-            /// Size in bytes of the field `
-            #[doc = !($field)]
-            /// `
-            pub const fn [< $field _len >]() -> usize{
-                $len
-            }
-            )+
-
-            /// Verify that `len` is sufficiently long to hold [Self]
-            pub fn check_size(len: usize) -> Result<(), RosenpassError>{
-                let required_size = $( $len + )+ 0;
-                let actual_size = len;
-                if required_size != actual_size {
-                    Err(RosenpassError::BufferSizeMismatch {
-                        required_size,
-                        actual_size,
-                    })
-                }else{
-                    Ok(())
-                }
-            }
-        }
-
-        // read-only accessor functions
-        impl<'a, __ContainerType $(, $( $generic: LenseView ),+ )?> $type<&'a __ContainerType $(, $( $generic ),+ )?>
-        where
-            __ContainerType: std::ops::Index<std::ops::Range<usize>> + ?Sized,
-        {
-            data_lense!{token_muncher_ref @ 0 ; $( $( $attr )* ; $field : $len ),+ }
-
-            /// View into all bytes belonging to this Lense
-            pub fn all_bytes(&self) -> &__ContainerType::Output {
-                &self.0[0..Self::LEN]
-            }
-        }
-
-        // mutable accessor functions
-        impl<'a, __ContainerType $(, $( $generic: LenseView ),+ )?> $type<&'a mut __ContainerType $(, $( $generic ),+ )?>
-        where
-            __ContainerType: std::ops::IndexMut<std::ops::Range<usize>> + ?Sized,
-        {
-            data_lense!{token_muncher_ref @ 0 ; $( $( $attr )* ; $field : $len ),+ }
-            data_lense!{token_muncher_mut @ 0 ; $( $( $attr )* ; $field : $len ),+ }
-
-            /// View into all bytes belonging to this Lense
-            pub fn all_bytes(&self) -> &__ContainerType::Output {
-                &self.0[0..Self::LEN]
-            }
-
-            /// View into all bytes belonging to this Lense
-            pub fn all_bytes_mut(&mut self) -> &mut __ContainerType::Output {
-                &mut self.0[0..Self::LEN]
-            }
-        }
-
-        // lense trait, allowing us to know the implementing lenses size
-        impl<__ContainerType $(, $( $generic: LenseView ),+ )? > LenseView for $type<__ContainerType $(, $( $generic ),+ )? >{
-            /// Number of bytes required to store this type in binary format
-            const LEN: usize = $( $len + )+ 0;
-        }
-
-        /// Extension trait to allow checked creation of a lense over
-        /// some byte slice that contains a
-        #[doc = data_lense!(maybe_docstring_link $type)]
-        pub trait [< $type Ext >] {
-            type __ContainerType;
-
-            /// Create a lense to the byte slice
-            fn [< $type:snake >] $(< $($generic : LenseView),* >)? (self) -> Result< $type<Self::__ContainerType, $( $($generic),+ )? >, RosenpassError>;
-
-            /// Create a lense to the byte slice, automatically truncating oversized buffers
-            fn [< $type:snake _ truncating >] $(< $($generic : LenseView),* >)? (self) -> Result< $type<Self::__ContainerType, $( $($generic),+ )? >, RosenpassError>;
-        }
-
-        impl<'a> [< $type Ext >] for &'a [u8] {
-            type __ContainerType = &'a [u8];
-
-            fn [< $type:snake >] $(< $($generic : LenseView),* >)? (self) -> Result< $type<Self::__ContainerType, $( $($generic),+ )? >, RosenpassError> {
-                $type::<Self::__ContainerType, $( $($generic),+ )? >::check_size(self.len())?;
-                Ok($type ( self, $( $( ::core::marker::PhantomData::<$generic>  ),+ )? ))
-            }
-
-            fn [< $type:snake _ truncating >] $(< $($generic : LenseView),* >)? (self) -> Result< $type<Self::__ContainerType, $( $($generic),+ )? >, RosenpassError> {
-                let required_size = $( $len + )+ 0;
-                let actual_size = self.len();
-                if actual_size < required_size {
-                    return Err(RosenpassError::BufferSizeMismatch {
-                        required_size,
-                        actual_size,
-                    });
-                }
-
-                [< $type Ext >]::[< $type:snake >](&self[..required_size])
-            }
-        }
-
-        impl<'a> [< $type Ext >] for &'a mut [u8] {
-            type __ContainerType = &'a mut [u8];
-            fn [< $type:snake >] $(< $($generic : LenseView),* >)? (self) -> Result< $type<Self::__ContainerType, $( $($generic),+ )? >, RosenpassError> {
-                $type::<Self::__ContainerType, $( $($generic),+ )? >::check_size(self.len())?;
-                Ok($type ( self, $( $( ::core::marker::PhantomData::<$generic>  ),+ )? ))
-            }
-
-            fn [< $type:snake _ truncating >] $(< $($generic : LenseView),* >)? (self) -> Result< $type<Self::__ContainerType, $( $($generic),+ )? >, RosenpassError> {
-                let required_size = $( $len + )+ 0;
-                let actual_size = self.len();
-                if actual_size < required_size {
-                    return Err(RosenpassError::BufferSizeMismatch {
-                        required_size,
-                        actual_size,
-                    });
-                }
-
-                [< $type Ext >]::[< $type:snake >](&mut self[..required_size])
-            }
-        }
-    });
-);
-
-/// Common trait shared by all Lenses
-pub trait LenseView {
-    const LEN: usize;
-}
-
-data_lense! { Envelope<M> :=
+lense! { Envelope<M> :=
     /// [MsgType] of this message
     msg_type: 1,
     /// Reserved for future use
@@ -270,35 +66,35 @@ data_lense! { Envelope<M> :=
     cookie: 16
 }
 
-data_lense! { InitHello :=
+lense! { InitHello :=
     /// Randomly generated connection id
     sidi: 4,
     /// Kyber 512 Ephemeral Public Key
-    epki: EphemeralKEM::PK_LEN,
+    epki: EphemeralKem::PK_LEN,
     /// Classic McEliece Ciphertext
-    sctr: StaticKEM::CT_LEN,
+    sctr: StaticKem::CT_LEN,
     /// Encryped: 16 byte hash of McEliece initiator static key
     pidic: aead::TAG_LEN + 32,
     /// Encrypted TAI64N Time Stamp (against replay attacks)
     auth: aead::TAG_LEN
 }
 
-data_lense! { RespHello :=
+lense! { RespHello :=
     /// Randomly generated connection id
     sidr: 4,
     /// Copied from InitHello
     sidi: 4,
     /// Kyber 512 Ephemeral Ciphertext
-    ecti: EphemeralKEM::CT_LEN,
+    ecti: EphemeralKem::CT_LEN,
     /// Classic McEliece Ciphertext
-    scti: StaticKEM::CT_LEN,
+    scti: StaticKem::CT_LEN,
     /// Empty encrypted message (just an auth tag)
     auth: aead::TAG_LEN,
     /// Responders handshake state in encrypted form
     biscuit: BISCUIT_CT_LEN
 }
 
-data_lense! { InitConf :=
+lense! { InitConf :=
     /// Copied from InitHello
     sidi: 4,
     /// Copied from RespHello
@@ -309,7 +105,7 @@ data_lense! { InitConf :=
     auth: aead::TAG_LEN
 }
 
-data_lense! { EmptyData :=
+lense! { EmptyData :=
     /// Copied from RespHello
     sid: 4,
     /// Nonce
@@ -318,7 +114,7 @@ data_lense! { EmptyData :=
     auth: aead::TAG_LEN
 }
 
-data_lense! { Biscuit :=
+lense! { Biscuit :=
     /// H(spki) – Ident ifies the initiator
     pidi: KEY_LEN,
     /// The biscuit number (replay protection)
@@ -327,11 +123,11 @@ data_lense! { Biscuit :=
     ck: KEY_LEN
 }
 
-data_lense! { DataMsg :=
+lense! { DataMsg :=
     dummy: 4
 }
 
-data_lense! { CookieReply :=
+lense! { CookieReply :=
     dummy: 4
 }
 

rosenpass/src/pqkem.rs

@@ -1,168 +0,0 @@
-//! Traits and implementations for Key Encapsulation Mechanisms (KEMs)
-//!
-//! KEMs are the interface provided by almost all post-quantum
-//! secure key exchange mechanisms.
-//!
-//! Conceptually KEMs are akin to public-key encryption, but instead of encrypting
-//! arbitrary data, KEMs are limited to the transmission of keys, randomly chosen during
-//!
-//! encapsulation.
-//! The [KEM] Trait describes the basic API offered by a Key Encapsulation
-//! Mechanism. Two implementations for it are provided, [StaticKEM] and [EphemeralKEM].
-
-use crate::{RosenpassError, RosenpassMaybeError};
-
-/// Key Encapsulation Mechanism
-///
-/// The KEM interface defines three operations: Key generation, key encapsulation and key
-/// decapsulation.
-pub trait KEM {
-    /// Secrete Key length
-    const SK_LEN: usize;
-    /// Public Key length
-    const PK_LEN: usize;
-    /// Ciphertext length
-    const CT_LEN: usize;
-    /// Shared Secret length
-    const SHK_LEN: usize;
-
-    /// Generate a keypair consisting of secret key (`sk`) and public key (`pk`)
-    ///
-    /// `keygen() -> sk, pk`
-    fn keygen(sk: &mut [u8], pk: &mut [u8]) -> Result<(), RosenpassError>;
-
-    /// From a public key (`pk`), generate a shared key (`shk`, for local use)
-    /// and a cipher text (`ct`, to be sent to the owner of the `pk`).
-    ///
-    /// `encaps(pk) -> shk, ct`
-    fn encaps(shk: &mut [u8], ct: &mut [u8], pk: &[u8]) -> Result<(), RosenpassError>;
-
-    /// From a secret key (`sk`) and a cipher text (`ct`) derive a shared key
-    /// (`shk`)
-    ///
-    /// `decaps(sk, ct) -> shk`
-    fn decaps(shk: &mut [u8], sk: &[u8], ct: &[u8]) -> Result<(), RosenpassError>;
-}
-
-/// A KEM that is secure against Chosen Ciphertext Attacks (CCA).
-/// In the context of rosenpass this is used for static keys.
-/// Uses [Classic McEliece](https://classic.mceliece.org/) 460896 from liboqs.
-///
-/// Classic McEliece is chosen because of its high security margin and its small
-/// ciphertexts. The public keys are humongous, but (being static keys) the are never transmitted over
-/// the wire so this is not a big problem.
-pub struct StaticKEM;
-
-/// # Safety
-///
-/// This Trait impl calls unsafe [oqs_sys] functions, that write to byte
-/// slices only identified using raw pointers. It must be ensured that the raw
-/// pointers point into byte slices of sufficient length, to avoid UB through
-/// overwriting of arbitrary data. This is checked in the following code before
-/// the unsafe calls, and an early return with an Err occurs if the byte slice
-/// size does not match the required size.
-///
-/// __Note__: This requirement is stricter than necessary, it would suffice
-/// to only check that the buffers are big enough, allowing them to be even
-/// bigger. However, from a correctness point of view it does not make sense to
-/// allow bigger buffers.
-impl KEM for StaticKEM {
-    const SK_LEN: usize = oqs_sys::kem::OQS_KEM_classic_mceliece_460896_length_secret_key as usize;
-    const PK_LEN: usize = oqs_sys::kem::OQS_KEM_classic_mceliece_460896_length_public_key as usize;
-    const CT_LEN: usize = oqs_sys::kem::OQS_KEM_classic_mceliece_460896_length_ciphertext as usize;
-    const SHK_LEN: usize =
-        oqs_sys::kem::OQS_KEM_classic_mceliece_460896_length_shared_secret as usize;
-
-    fn keygen(sk: &mut [u8], pk: &mut [u8]) -> Result<(), RosenpassError> {
-        RosenpassError::check_buffer_size(sk.len(), Self::SK_LEN)?;
-        RosenpassError::check_buffer_size(pk.len(), Self::PK_LEN)?;
-        unsafe {
-            oqs_sys::kem::OQS_KEM_classic_mceliece_460896_keypair(pk.as_mut_ptr(), sk.as_mut_ptr())
-                .to_rg_error()
-        }
-    }
-
-    fn encaps(shk: &mut [u8], ct: &mut [u8], pk: &[u8]) -> Result<(), RosenpassError> {
-        RosenpassError::check_buffer_size(shk.len(), Self::SHK_LEN)?;
-        RosenpassError::check_buffer_size(ct.len(), Self::CT_LEN)?;
-        RosenpassError::check_buffer_size(pk.len(), Self::PK_LEN)?;
-        unsafe {
-            oqs_sys::kem::OQS_KEM_classic_mceliece_460896_encaps(
-                ct.as_mut_ptr(),
-                shk.as_mut_ptr(),
-                pk.as_ptr(),
-            )
-            .to_rg_error()
-        }
-    }
-
-    fn decaps(shk: &mut [u8], sk: &[u8], ct: &[u8]) -> Result<(), RosenpassError> {
-        RosenpassError::check_buffer_size(shk.len(), Self::SHK_LEN)?;
-        RosenpassError::check_buffer_size(sk.len(), Self::SK_LEN)?;
-        RosenpassError::check_buffer_size(ct.len(), Self::CT_LEN)?;
-        unsafe {
-            oqs_sys::kem::OQS_KEM_classic_mceliece_460896_decaps(
-                shk.as_mut_ptr(),
-                ct.as_ptr(),
-                sk.as_ptr(),
-            )
-            .to_rg_error()
-        }
-    }
-}
-
-/// Implements a KEM that is secure against Chosen Plaintext Attacks (CPA).
-/// In the context of rosenpass this is used for ephemeral keys.
-/// Currently the implementation uses
-/// [Kyber 512](https://openquantumsafe.org/liboqs/algorithms/kem/kyber) from liboqs.
-///
-/// This is being used for ephemeral keys; since these are use-once the first post quantum
-/// wireguard paper claimed that CPA security would be sufficient. Nonetheless we choose kyber
-/// which provides CCA security since there are no publicly vetted KEMs out there which provide
-/// only CPA security.
-pub struct EphemeralKEM;
-
-/// # Safety
-///
-/// This Trait impl calls unsafe [oqs_sys] functions, that write to byte
-/// slices only identified using raw pointers. It must be ensured that the raw
-/// pointers point into byte slices of sufficient length, to avoid UB through
-/// overwriting of arbitrary data. This is checked in the following code before
-/// the unsafe calls, and an early return with an Err occurs if the byte slice
-/// size does not match the required size.
-///
-/// __Note__: This requirement is stricter than necessary, it would suffice
-/// to only check that the buffers are big enough, allowing them to be even
-/// bigger. However, from a correctness point of view it does not make sense to
-/// allow bigger buffers.
-impl KEM for EphemeralKEM {
-    const SK_LEN: usize = oqs_sys::kem::OQS_KEM_kyber_512_length_secret_key as usize;
-    const PK_LEN: usize = oqs_sys::kem::OQS_KEM_kyber_512_length_public_key as usize;
-    const CT_LEN: usize = oqs_sys::kem::OQS_KEM_kyber_512_length_ciphertext as usize;
-    const SHK_LEN: usize = oqs_sys::kem::OQS_KEM_kyber_512_length_shared_secret as usize;
-    fn keygen(sk: &mut [u8], pk: &mut [u8]) -> Result<(), RosenpassError> {
-        RosenpassError::check_buffer_size(sk.len(), Self::SK_LEN)?;
-        RosenpassError::check_buffer_size(pk.len(), Self::PK_LEN)?;
-        unsafe {
-            oqs_sys::kem::OQS_KEM_kyber_512_keypair(pk.as_mut_ptr(), sk.as_mut_ptr()).to_rg_error()
-        }
-    }
-    fn encaps(shk: &mut [u8], ct: &mut [u8], pk: &[u8]) -> Result<(), RosenpassError> {
-        RosenpassError::check_buffer_size(shk.len(), Self::SHK_LEN)?;
-        RosenpassError::check_buffer_size(ct.len(), Self::CT_LEN)?;
-        RosenpassError::check_buffer_size(pk.len(), Self::PK_LEN)?;
-        unsafe {
-            oqs_sys::kem::OQS_KEM_kyber_512_encaps(ct.as_mut_ptr(), shk.as_mut_ptr(), pk.as_ptr())
-                .to_rg_error()
-        }
-    }
-    fn decaps(shk: &mut [u8], sk: &[u8], ct: &[u8]) -> Result<(), RosenpassError> {
-        RosenpassError::check_buffer_size(shk.len(), Self::SHK_LEN)?;
-        RosenpassError::check_buffer_size(sk.len(), Self::SK_LEN)?;
-        RosenpassError::check_buffer_size(ct.len(), Self::CT_LEN)?;
-        unsafe {
-            oqs_sys::kem::OQS_KEM_kyber_512_decaps(shk.as_mut_ptr(), ct.as_ptr(), sk.as_ptr())
-                .to_rg_error()
-        }
-    }
-}

rosenpass/src/prftree.rs

@@ -1,106 +0,0 @@
-//! Implementation of the tree-like structure used for the label derivation in [labeled_prf](crate::labeled_prf)
-use crate::coloring::Secret;
-
-use anyhow::Result;
-use rosenpass_ciphers::{hash, KEY_LEN};
-use rosenpass_to::To;
-
-// TODO Use a proper Dec interface
-#[derive(Clone, Debug)]
-pub struct PrfTree([u8; KEY_LEN]);
-#[derive(Clone, Debug)]
-pub struct PrfTreeBranch([u8; KEY_LEN]);
-#[derive(Clone, Debug)]
-pub struct SecretPrfTree(Secret<KEY_LEN>);
-#[derive(Clone, Debug)]
-pub struct SecretPrfTreeBranch(Secret<KEY_LEN>);
-
-impl PrfTree {
-    pub fn zero() -> Self {
-        Self([0u8; KEY_LEN])
-    }
-
-    pub fn dup(self) -> PrfTreeBranch {
-        PrfTreeBranch(self.0)
-    }
-
-    pub fn into_secret_prf_tree(self) -> SecretPrfTree {
-        SecretPrfTree(Secret::from_slice(&self.0))
-    }
-
-    // TODO: Protocol! Use domain separation to ensure that
-    pub fn mix(self, v: &[u8]) -> Result<Self> {
-        Ok(Self(hash::hash(&self.0, v).collect::<[u8; KEY_LEN]>()?))
-    }
-
-    pub fn mix_secret<const N: usize>(self, v: Secret<N>) -> Result<SecretPrfTree> {
-        SecretPrfTree::prf_invoc(&self.0, v.secret())
-    }
-
-    pub fn into_value(self) -> [u8; KEY_LEN] {
-        self.0
-    }
-}
-
-impl PrfTreeBranch {
-    pub fn mix(&self, v: &[u8]) -> Result<PrfTree> {
-        Ok(PrfTree(hash::hash(&self.0, v).collect::<[u8; KEY_LEN]>()?))
-    }
-
-    pub fn mix_secret<const N: usize>(&self, v: Secret<N>) -> Result<SecretPrfTree> {
-        SecretPrfTree::prf_invoc(&self.0, v.secret())
-    }
-}
-
-impl SecretPrfTree {
-    pub fn prf_invoc(k: &[u8], d: &[u8]) -> Result<SecretPrfTree> {
-        let mut r = SecretPrfTree(Secret::zero());
-        hash::hash(k, d).to(r.0.secret_mut())?;
-        Ok(r)
-    }
-
-    pub fn zero() -> Self {
-        Self(Secret::zero())
-    }
-
-    pub fn dup(self) -> SecretPrfTreeBranch {
-        SecretPrfTreeBranch(self.0)
-    }
-
-    pub fn danger_from_secret(k: Secret<KEY_LEN>) -> Self {
-        Self(k)
-    }
-
-    pub fn mix(self, v: &[u8]) -> Result<SecretPrfTree> {
-        Self::prf_invoc(self.0.secret(), v)
-    }
-
-    pub fn mix_secret<const N: usize>(self, v: Secret<N>) -> Result<SecretPrfTree> {
-        Self::prf_invoc(self.0.secret(), v.secret())
-    }
-
-    pub fn into_secret(self) -> Secret<KEY_LEN> {
-        self.0
-    }
-
-    pub fn into_secret_slice(mut self, v: &[u8], dst: &[u8]) -> Result<()> {
-        hash::hash(v, dst).to(self.0.secret_mut())
-    }
-}
-
-impl SecretPrfTreeBranch {
-    pub fn mix(&self, v: &[u8]) -> Result<SecretPrfTree> {
-        SecretPrfTree::prf_invoc(self.0.secret(), v)
-    }
-
-    pub fn mix_secret<const N: usize>(&self, v: Secret<N>) -> Result<SecretPrfTree> {
-        SecretPrfTree::prf_invoc(self.0.secret(), v.secret())
-    }
-
-    // TODO: This entire API is not very nice; we need this for biscuits, but
-    // it might be better to extract a special "biscuit"
-    // labeled subkey and reinitialize the chain with this
-    pub fn danger_into_secret(self) -> Secret<KEY_LEN> {
-        self.0
-    }
-}

rosenpass/src/protocol.rs

@@ -19,22 +19,20 @@
 //! [CryptoServer].
 //!
 //! ```
+//! use rosenpass_cipher_traits::Kem;
+//! use rosenpass_ciphers::kem::StaticKem;
 //! use rosenpass::{
-//!     pqkem::{StaticKEM, KEM},
 //!     protocol::{SSk, SPk, MsgBuf, PeerPtr, CryptoServer, SymKey},
 //! };
 //! # fn main() -> anyhow::Result<()> {
 //!
-//! // always initialize libsodium before anything
-//! rosenpass_sodium::init()?;
-//!
 //! // initialize secret and public key for peer a ...
 //! let (mut peer_a_sk, mut peer_a_pk) = (SSk::zero(), SPk::zero());
-//! StaticKEM::keygen(peer_a_sk.secret_mut(), peer_a_pk.secret_mut())?;
+//! StaticKem::keygen(peer_a_sk.secret_mut(), peer_a_pk.secret_mut())?;
 //!
 //! // ... and for peer b
 //! let (mut peer_b_sk, mut peer_b_pk) = (SSk::zero(), SPk::zero());
-//! StaticKEM::keygen(peer_b_sk.secret_mut(), peer_b_pk.secret_mut())?;
+//! StaticKem::keygen(peer_b_sk.secret_mut(), peer_b_pk.secret_mut())?;
 //!
 //! // initialize server and a pre-shared key
 //! let psk = SymKey::random();
@@ -67,20 +65,24 @@
 //! # }
 //! ```
 
-use crate::{
-    coloring::*,
-    labeled_prf as lprf,
-    msgs::*,
-    pqkem::*,
-    prftree::{SecretPrfTree, SecretPrfTreeBranch},
-};
-use anyhow::{bail, ensure, Context, Result};
-use rosenpass_ciphers::{aead, xaead, KEY_LEN};
-use rosenpass_util::{cat, mem::cpy_min, ord::max_usize, time::Timebase};
 use std::collections::hash_map::{
     Entry::{Occupied, Vacant},
     HashMap,
 };
+use std::convert::Infallible;
+
+use anyhow::{bail, ensure, Context, Result};
+
+use rosenpass_cipher_traits::Kem;
+use rosenpass_ciphers::hash_domain::{SecretHashDomain, SecretHashDomainNamespace};
+use rosenpass_ciphers::kem::{EphemeralKem, StaticKem};
+use rosenpass_ciphers::{aead, xaead, KEY_LEN};
+use rosenpass_constant_time as constant_time;
+use rosenpass_lenses::LenseView;
+use rosenpass_secret_memory::{Public, Secret};
+use rosenpass_util::{cat, mem::cpy_min, ord::max_usize, time::Timebase};
+
+use crate::{hash_domains, msgs::*};
 
 // CONSTANTS & SETTINGS //////////////////////////
 
@@ -139,10 +141,10 @@ pub fn has_happened(ev: Timing, now: Timing) -> bool {
 
 // DATA STRUCTURES & BASIC TRAITS & ACCESSORS ////
 
-pub type SPk = Secret<{ StaticKEM::PK_LEN }>; // Just Secret<> instead of Public<> so it gets allocated on the heap
-pub type SSk = Secret<{ StaticKEM::SK_LEN }>;
-pub type EPk = Public<{ EphemeralKEM::PK_LEN }>;
-pub type ESk = Secret<{ EphemeralKEM::SK_LEN }>;
+pub type SPk = Secret<{ StaticKem::PK_LEN }>; // Just Secret<> instead of Public<> so it gets allocated on the heap
+pub type SSk = Secret<{ StaticKem::SK_LEN }>;
+pub type EPk = Public<{ EphemeralKem::PK_LEN }>;
+pub type ESk = Secret<{ EphemeralKem::SK_LEN }>;
 
 pub type SymKey = Secret<KEY_LEN>;
 pub type SymHash = Public<KEY_LEN>;
@@ -233,7 +235,7 @@ pub struct HandshakeState {
     /// Session ID of Responder
     pub sidr: SessionId,
     /// Chaining Key
-    pub ck: SecretPrfTreeBranch,
+    pub ck: SecretHashDomainNamespace, // TODO: We should probably add an abstr
 }
 
 #[derive(Hash, PartialEq, Eq, PartialOrd, Ord, Debug, Copy, Clone)]
@@ -285,7 +287,7 @@ pub struct Session {
     pub sidt: SessionId,
     pub handshake_role: HandshakeRole,
     // Crypto
-    pub ck: SecretPrfTreeBranch,
+    pub ck: SecretHashDomainNamespace,
     /// Key for Transmission ("transmission key mine")
     pub txkm: SymKey,
     /// Key for Reception ("transmission key theirs")
@@ -460,7 +462,7 @@ impl CryptoServer {
     #[rustfmt::skip]
     pub fn pidm(&self) -> Result<PeerId> {
         Ok(Public::new(
-            lprf::peerid()?
+            hash_domains::peerid()?
                 .mix(self.spkm.secret())?
                 .into_value()))
     }
@@ -590,7 +592,7 @@ impl Peer {
     #[rustfmt::skip]
     pub fn pidt(&self) -> Result<PeerId> {
         Ok(Public::new(
-            lprf::peerid()?
+            hash_domains::peerid()?
                 .mix(self.spkt.secret())?
                 .into_value()))
     }
@@ -603,7 +605,7 @@ impl Session {
             sidm: SessionId::zero(),
             sidt: SessionId::zero(),
             handshake_role: HandshakeRole::Initiator,
-            ck: SecretPrfTree::zero().dup(),
+            ck: SecretHashDomain::zero().dup(),
             txkm: SymKey::zero(),
             txkt: SymKey::zero(),
             txnm: 0,
@@ -1154,7 +1156,7 @@ impl IniHsPtr {
                         .min(ih.tx_count as f64),
                 )
                 * RETRANSMIT_DELAY_JITTER
-                * (rosenpass_sodium::helpers::rand_f64() + 1.0); // TODO: Replace with the rand crate
+                * (rand::random::<f64>() + 1.0); // TODO: Replace with the rand crate
         ih.tx_count += 1;
         Ok(())
     }
@@ -1174,7 +1176,7 @@ where
 {
     /// Calculate the message authentication code (`mac`)
     pub fn seal(&mut self, peer: PeerPtr, srv: &CryptoServer) -> Result<()> {
-        let mac = lprf::mac()?
+        let mac = hash_domains::mac()?
             .mix(peer.get(srv).spkt.secret())?
             .mix(self.until_mac())?;
         self.mac_mut()
@@ -1189,8 +1191,10 @@ where
 {
     /// Check the message authentication code
     pub fn check_seal(&self, srv: &CryptoServer) -> Result<bool> {
-        let expected = lprf::mac()?.mix(srv.spkm.secret())?.mix(self.until_mac())?;
-        Ok(rosenpass_sodium::helpers::memcmp(
+        let expected = hash_domains::mac()?
+            .mix(srv.spkm.secret())?
+            .mix(self.until_mac())?;
+        Ok(constant_time::memcmp(
             self.mac(),
             &expected.into_value()[..16],
         ))
@@ -1219,38 +1223,38 @@ impl HandshakeState {
         Self {
             sidi: SessionId::zero(),
             sidr: SessionId::zero(),
-            ck: SecretPrfTree::zero().dup(),
+            ck: SecretHashDomain::zero().dup(),
         }
     }
 
     pub fn erase(&mut self) {
-        self.ck = SecretPrfTree::zero().dup();
+        self.ck = SecretHashDomain::zero().dup();
     }
 
     pub fn init(&mut self, spkr: &[u8]) -> Result<&mut Self> {
-        self.ck = lprf::ckinit()?.mix(spkr)?.into_secret_prf_tree().dup();
+        self.ck = hash_domains::ckinit()?.turn_secret().mix(spkr)?.dup();
         Ok(self)
     }
 
     pub fn mix(&mut self, a: &[u8]) -> Result<&mut Self> {
-        self.ck = self.ck.mix(&lprf::mix()?)?.mix(a)?.dup();
+        self.ck = self.ck.mix(&hash_domains::mix()?)?.mix(a)?.dup();
         Ok(self)
     }
 
     pub fn encrypt_and_mix(&mut self, ct: &mut [u8], pt: &[u8]) -> Result<&mut Self> {
-        let k = self.ck.mix(&lprf::hs_enc()?)?.into_secret();
+        let k = self.ck.mix(&hash_domains::hs_enc()?)?.into_secret();
         aead::encrypt(ct, k.secret(), &[0u8; aead::NONCE_LEN], &[], pt)?;
         self.mix(ct)
     }
 
     pub fn decrypt_and_mix(&mut self, pt: &mut [u8], ct: &[u8]) -> Result<&mut Self> {
-        let k = self.ck.mix(&lprf::hs_enc()?)?.into_secret();
+        let k = self.ck.mix(&hash_domains::hs_enc()?)?.into_secret();
         aead::decrypt(pt, k.secret(), &[0u8; aead::NONCE_LEN], &[], ct)?;
         self.mix(ct)
     }
 
     // I loathe "error: constant expression depends on a generic parameter"
-    pub fn encaps_and_mix<T: KEM, const SHK_LEN: usize>(
+    pub fn encaps_and_mix<T: Kem<Error = Infallible>, const SHK_LEN: usize>(
         &mut self,
         ct: &mut [u8],
         pk: &[u8],
@@ -1260,7 +1264,7 @@ impl HandshakeState {
         self.mix(pk)?.mix(shk.secret())?.mix(ct)
     }
 
-    pub fn decaps_and_mix<T: KEM, const SHK_LEN: usize>(
+    pub fn decaps_and_mix<T: Kem<Error = Infallible>, const SHK_LEN: usize>(
         &mut self,
         sk: &[u8],
         pk: &[u8],
@@ -1290,14 +1294,14 @@ impl HandshakeState {
             .copy_from_slice(self.ck.clone().danger_into_secret().secret());
 
         // calculate ad contents
-        let ad = lprf::biscuit_ad()?
+        let ad = hash_domains::biscuit_ad()?
             .mix(srv.spkm.secret())?
             .mix(self.sidi.as_slice())?
             .mix(self.sidr.as_slice())?
             .into_value();
 
         // consume biscuit no
-        rosenpass_sodium::helpers::increment(&mut *srv.biscuit_ctr);
+        constant_time::increment(&mut *srv.biscuit_ctr);
 
         // The first bit of the nonce indicates which biscuit key was used
         // TODO: This is premature optimization. Remove!
@@ -1325,7 +1329,7 @@ impl HandshakeState {
         let bk = BiscuitKeyPtr(((biscuit_ct[0] & 0b1000_0000) >> 7) as usize);
 
         // Calculate additional data fields
-        let ad = lprf::biscuit_ad()?
+        let ad = hash_domains::biscuit_ad()?
             .mix(srv.spkm.secret())?
             .mix(sidi.as_slice())?
             .mix(sidr.as_slice())?
@@ -1343,7 +1347,7 @@ impl HandshakeState {
 
         // Reconstruct the biscuit fields
         let no = BiscuitId::from_slice(biscuit.biscuit_no());
-        let ck = SecretPrfTree::danger_from_secret(Secret::from_slice(biscuit.ck())).dup();
+        let ck = SecretHashDomain::danger_from_secret(Secret::from_slice(biscuit.ck())).dup();
         let pid = PeerId::from_slice(biscuit.pidi());
 
         // Reconstruct the handshake state
@@ -1360,8 +1364,7 @@ impl HandshakeState {
         // indicates retransmission
         // TODO: Handle retransmissions without involving the crypto code
         ensure!(
-            rosenpass_sodium::helpers::compare(biscuit.biscuit_no(), &*peer.get(srv).biscuit_used)
-                >= 0,
+            constant_time::compare(biscuit.biscuit_no(), &*peer.get(srv).biscuit_used) >= 0,
             "Rejecting biscuit: Outdated biscuit number"
         );
 
@@ -1370,8 +1373,8 @@ impl HandshakeState {
 
     pub fn enter_live(self, srv: &CryptoServer, role: HandshakeRole) -> Result<Session> {
         let HandshakeState { ck, sidi, sidr } = self;
-        let tki = ck.mix(&lprf::ini_enc()?)?.into_secret();
-        let tkr = ck.mix(&lprf::res_enc()?)?.into_secret();
+        let tki = ck.mix(&hash_domains::ini_enc()?)?.into_secret();
+        let tkr = ck.mix(&hash_domains::res_enc()?)?.into_secret();
         let created_at = srv.timebase.now();
         let (ntx, nrx) = (0, 0);
         let (mysid, peersid, ktx, krx) = match role {
@@ -1402,7 +1405,7 @@ impl CryptoServer {
             .get(self)
             .as_ref()
             .with_context(|| format!("No current session for peer {:?}", peer))?;
-        Ok(session.ck.mix(&lprf::osk()?)?.into_secret())
+        Ok(session.ck.mix(&hash_domains::osk()?)?.into_secret())
     }
 }
 
@@ -1424,7 +1427,7 @@ impl CryptoServer {
         ih.sidi_mut().copy_from_slice(&hs.core.sidi.value);
 
         // IHI3
-        EphemeralKEM::keygen(hs.eski.secret_mut(), &mut *hs.epki)?;
+        EphemeralKem::keygen(hs.eski.secret_mut(), &mut *hs.epki)?;
         ih.epki_mut().copy_from_slice(&hs.epki.value);
 
         // IHI4
@@ -1432,7 +1435,7 @@ impl CryptoServer {
 
         // IHI5
         hs.core
-            .encaps_and_mix::<StaticKEM, { StaticKEM::SHK_LEN }>(
+            .encaps_and_mix::<StaticKem, { StaticKem::SHK_LEN }>(
                 ih.sctr_mut(),
                 peer.get(self).spkt.secret(),
             )?;
@@ -1471,7 +1474,7 @@ impl CryptoServer {
         core.mix(ih.sidi())?.mix(ih.epki())?;
 
         // IHR5
-        core.decaps_and_mix::<StaticKEM, { StaticKEM::SHK_LEN }>(
+        core.decaps_and_mix::<StaticKem, { StaticKem::SHK_LEN }>(
             self.sskm.secret(),
             self.spkm.secret(),
             ih.sctr(),
@@ -1501,10 +1504,10 @@ impl CryptoServer {
         core.mix(rh.sidr())?.mix(rh.sidi())?;
 
         // RHR4
-        core.encaps_and_mix::<EphemeralKEM, { EphemeralKEM::SHK_LEN }>(rh.ecti_mut(), ih.epki())?;
+        core.encaps_and_mix::<EphemeralKem, { EphemeralKem::SHK_LEN }>(rh.ecti_mut(), ih.epki())?;
 
         // RHR5
-        core.encaps_and_mix::<StaticKEM, { StaticKEM::SHK_LEN }>(
+        core.encaps_and_mix::<StaticKem, { StaticKem::SHK_LEN }>(
             rh.scti_mut(),
             peer.get(self).spkt.secret(),
         )?;
@@ -1569,14 +1572,14 @@ impl CryptoServer {
         core.mix(rh.sidr())?.mix(rh.sidi())?;
 
         // RHI4
-        core.decaps_and_mix::<EphemeralKEM, { EphemeralKEM::SHK_LEN }>(
+        core.decaps_and_mix::<EphemeralKem, { EphemeralKem::SHK_LEN }>(
             hs!().eski.secret(),
             &*hs!().epki,
             rh.ecti(),
         )?;
 
         // RHI5
-        core.decaps_and_mix::<StaticKEM, { StaticKEM::SHK_LEN }>(
+        core.decaps_and_mix::<StaticKem, { StaticKem::SHK_LEN }>(
             self.sskm.secret(),
             self.spkm.secret(),
             rh.scti(),
@@ -1638,7 +1641,7 @@ impl CryptoServer {
         core.decrypt_and_mix(&mut [0u8; 0], ic.auth())?;
 
         // ICR5
-        if rosenpass_sodium::helpers::compare(&*biscuit_no, &*peer.get(self).biscuit_used) > 0 {
+        if constant_time::compare(&*biscuit_no, &*peer.get(self).biscuit_used) > 0 {
             // ICR6
             peer.get_mut(self).biscuit_used = biscuit_no;
 
@@ -1754,8 +1757,6 @@ mod test {
     /// Through all this, the handshake should still successfully terminate;
     /// i.e. an exchanged key must be produced in both servers.
     fn handles_incorrect_size_messages() {
-        rosenpass_sodium::init().unwrap();
-
         stacker::grow(8 * 1024 * 1024, || {
             const OVERSIZED_MESSAGE: usize = ((MAX_MESSAGE_LEN as f32) * 1.2) as usize;
             type MsgBufPlus = Public<OVERSIZED_MESSAGE>;
@@ -1767,14 +1768,10 @@ mod test {
 
             // Process the entire handshake
             let mut msglen = Some(me.initiate_handshake(PEER0, &mut *resbuf).unwrap());
-            loop {
-                if let Some(l) = msglen {
-                    std::mem::swap(&mut me, &mut they);
-                    std::mem::swap(&mut msgbuf, &mut resbuf);
-                    msglen = test_incorrect_sizes_for_msg(&mut me, &*msgbuf, l, &mut *resbuf);
-                } else {
-                    break;
-                }
+            while let Some(l) = msglen {
+                std::mem::swap(&mut me, &mut they);
+                std::mem::swap(&mut msgbuf, &mut resbuf);
+                msglen = test_incorrect_sizes_for_msg(&mut me, &*msgbuf, l, &mut *resbuf);
             }
 
             assert_eq!(
@@ -1801,8 +1798,8 @@ mod test {
             }
 
             let res = srv.handle_msg(&msgbuf[..l], resbuf);
-            assert!(matches!(res, Err(_))); // handle_msg should raise an error
-            assert!(!resbuf.iter().find(|x| **x != 0).is_some()); // resbuf should not have been changed
+            assert!(res.is_err()); // handle_msg should raise an error
+            assert!(!resbuf.iter().any(|x| *x != 0)); // resbuf should not have been changed
         }
 
         // Apply the proper handle_msg operation
@@ -1812,7 +1809,7 @@ mod test {
     fn keygen() -> Result<(SSk, SPk)> {
         // TODO: Copied from the benchmark; deduplicate
         let (mut sk, mut pk) = (SSk::zero(), SPk::zero());
-        StaticKEM::keygen(sk.secret_mut(), pk.secret_mut())?;
+        StaticKem::keygen(sk.secret_mut(), pk.secret_mut())?;
         Ok((sk, pk))
     }
 

rosenpass/tests/integration_test.rs

@@ -30,11 +30,8 @@ fn generate_keys() {
 
 fn find_udp_socket() -> u16 {
     for port in 1025..=u16::MAX {
-        match UdpSocket::bind(("127.0.0.1", port)) {
-            Ok(_) => {
-                return port;
-            }
-            _ => {}
+        if UdpSocket::bind(("127.0.0.1", port)).is_ok() {
+            return port;
         }
     }
     panic!("no free UDP port found");
@@ -54,9 +51,9 @@ fn check_exchange() {
     for (secret_key_path, pub_key_path) in secret_key_paths.iter().zip(public_key_paths.iter()) {
         let output = test_bin::get_test_bin(BIN)
             .args(["gen-keys", "--secret-key"])
-            .arg(&secret_key_path)
+            .arg(secret_key_path)
             .arg("--public-key")
-            .arg(&pub_key_path)
+            .arg(pub_key_path)
             .output()
             .expect("Failed to start {BIN}");
 

rust-toolchain.toml

@@ -0,0 +1,2 @@
+[toolchain]
+channel = "1.74.1"

secret-memory/Cargo.toml

@@ -1,17 +1,22 @@
 [package]
-name = "rosenpass-sodium"
-authors = ["Karolin Varner <karo@cupdev.net>", "wucke13 <wucke13@gmail.com>"]
+name = "rosenpass-secret-memory"
 version = "0.1.0"
+authors = ["Karolin Varner <karo@cupdev.net>", "wucke13 <wucke13@gmail.com>"]
 edition = "2021"
 license = "MIT OR Apache-2.0"
-description = "Rosenpass internal bindings to libsodium"
+description = "Rosenpass internal utilities for storing secrets in memory"
 homepage = "https://rosenpass.eu/"
 repository = "https://github.com/rosenpass/rosenpass"
 readme = "readme.md"
 
 [dependencies]
-rosenpass-util = { workspace = true }
-rosenpass-to = { workspace = true }
 anyhow = { workspace = true }
-libsodium-sys-stable = { workspace = true }
+rosenpass-to = { workspace = true }
+rosenpass-util = { workspace = true }
+zeroize = { workspace = true }
+rand = { workspace = true }
+allocator-api2 = { workspace = true }
 log = { workspace = true }
+
+[dev-dependencies]
+allocator-api2-tests = { workspace = true }

secret-memory/readme.md

@@ -0,0 +1,5 @@
+# Rosenpass secure memory library
+
+Rosenpass internal library providing utilities for securely storing secret data in memory.
+
+This is an internal library; not guarantee is made about its API at this point in time.

secret-memory/src/alloc/memsec.rs

@@ -0,0 +1,86 @@
+use std::fmt;
+use std::ptr::NonNull;
+
+use allocator_api2::alloc::{AllocError, Allocator, Layout, Global};
+
+#[derive(Copy, Clone, Default)]
+struct MemsecAllocatorContents;
+
+/// Memory allocation using using the memsec crate
+#[derive(Copy, Clone, Default)]
+pub struct MemsecAllocator {
+    global: Global
+}
+
+/// A box backed by the memsec allocator
+pub type MemsecBox<T> = allocator_api2::boxed::Box<T, MemsecAllocator>;
+
+/// A vector backed by the memsec allocator
+pub type MemsecVec<T> = allocator_api2::vec::Vec<T, MemsecAllocator>;
+
+pub fn memsec_box<T>(x: T) -> MemsecBox<T> {
+    MemsecBox::<T>::new_in(x, MemsecAllocator::new())
+}
+
+pub fn memsec_vec<T>() -> MemsecVec<T> {
+    MemsecVec::<T>::new_in(MemsecAllocator::new())
+}
+
+impl MemsecAllocator {
+    pub fn new() -> Self {
+        Self {
+            global: Global
+        }
+    }
+}
+
+unsafe impl Allocator for MemsecAllocator {
+    fn allocate(&self, layout: Layout) -> Result<NonNull<[u8]>, AllocError> {
+        self.global.allocate(layout)
+    }
+
+    unsafe fn deallocate(&self, ptr: NonNull<u8>, _layout: Layout) {
+        unsafe { self.global.deallocate(ptr, _layout) }
+    }
+}
+
+impl fmt::Debug for MemsecAllocator {
+    fn fmt(&self, fmt: &mut fmt::Formatter) -> fmt::Result {
+        fmt.write_str("<memsec based Rust allocator>")
+    }
+}
+
+#[cfg(test)]
+mod test {
+    use allocator_api2_tests::make_test;
+
+    use super::*;
+
+    make_test! { test_sizes(MemsecAllocator::new()) }
+    make_test! { test_vec(MemsecAllocator::new()) }
+    make_test! { test_many_boxes(MemsecAllocator::new()) }
+
+    #[test]
+    fn memsec_allocation() {
+        let alloc = MemsecAllocator::new();
+        memsec_allocation_impl::<0>(&alloc);
+        memsec_allocation_impl::<7>(&alloc);
+        memsec_allocation_impl::<8>(&alloc);
+        memsec_allocation_impl::<64>(&alloc);
+        memsec_allocation_impl::<999>(&alloc);
+    }
+
+    fn memsec_allocation_impl<const N: usize>(alloc: &MemsecAllocator) {
+        let layout = Layout::new::<[u8; N]>();
+        let mem = alloc.allocate(layout).unwrap();
+
+        // https://libsodium.gitbook.io/doc/memory_management#guarded-heap-allocations
+        // promises us that allocated memory is initialized with the magic byte 0xDB
+        // and memsec promises to provide a reimplementation of the libsodium mechanism;
+        // it uses the magic value 0xD0 though
+        assert_eq!(unsafe { mem.as_ref() }, &[0xD0u8; N]);
+
+        let mem = NonNull::new(mem.as_ptr() as *mut u8).unwrap();
+        unsafe { alloc.deallocate(mem, layout) };
+    }
+}

secret-memory/src/alloc/mod.rs

@@ -0,0 +1,6 @@
+pub mod memsec;
+
+pub use crate::alloc::memsec::{
+    memsec_box as secret_box, memsec_vec as secret_vec, MemsecAllocator as SecretAllocator,
+    MemsecBox as SecretBox, MemsecVec as SecretVec,
+};

secret-memory/src/debug.rs

@@ -0,0 +1,20 @@
+use std::fmt;
+
+/// Writes the contents of an `&[u8]` as hexadecimal symbols to a [std::fmt::Formatter]
+pub fn debug_crypto_array(v: &[u8], fmt: &mut fmt::Formatter) -> fmt::Result {
+    fmt.write_str("[{}]=")?;
+    if v.len() > 64 {
+        for byte in &v[..32] {
+            std::fmt::LowerHex::fmt(byte, fmt)?;
+        }
+        fmt.write_str("…")?;
+        for byte in &v[v.len() - 32..] {
+            std::fmt::LowerHex::fmt(byte, fmt)?;
+        }
+    } else {
+        for byte in v {
+            std::fmt::LowerHex::fmt(byte, fmt)?;
+        }
+    }
+    Ok(())
+}

secret-memory/src/file.rs

@@ -0,0 +1,7 @@
+use std::path::Path;
+
+pub trait StoreSecret {
+    type Error;
+
+    fn store_secret<P: AsRef<Path>>(&self, path: P) -> Result<(), Self::Error>;
+}

secret-memory/src/lib.rs

@@ -0,0 +1,11 @@
+pub mod debug;
+pub mod file;
+pub mod rand;
+
+pub mod alloc;
+
+mod public;
+pub use crate::public::Public;
+
+mod secret;
+pub use crate::secret::Secret;

secret-memory/src/public.rs

@@ -0,0 +1,112 @@
+use crate::debug::debug_crypto_array;
+use rand::{Fill as Randomize, Rng};
+use rosenpass_to::{ops::copy_slice, To};
+use rosenpass_util::file::{fopen_r, LoadValue, ReadExactToEnd, StoreValue};
+use rosenpass_util::functional::mutating;
+use std::borrow::{Borrow, BorrowMut};
+use std::fmt;
+use std::ops::{Deref, DerefMut};
+use std::path::Path;
+
+/// Contains information in the form of a byte array that may be known to the
+/// public
+// TODO: We should get rid of the Public type; just use a normal value
+#[derive(Copy, Clone, Hash, PartialEq, Eq, PartialOrd, Ord)]
+#[repr(transparent)]
+pub struct Public<const N: usize> {
+    pub value: [u8; N],
+}
+
+impl<const N: usize> Public<N> {
+    /// Create a new [Public] from a byte slice
+    pub fn from_slice(value: &[u8]) -> Self {
+        copy_slice(value).to_this(Self::zero)
+    }
+
+    /// Create a new [Public] from a byte array
+    pub fn new(value: [u8; N]) -> Self {
+        Self { value }
+    }
+
+    /// Create a zero initialized [Public]
+    pub fn zero() -> Self {
+        Self { value: [0u8; N] }
+    }
+
+    /// Create a random initialized [Public]
+    pub fn random() -> Self {
+        mutating(Self::zero(), |r| r.randomize())
+    }
+
+    /// Randomize all bytes in an existing [Public]
+    pub fn randomize(&mut self) {
+        self.try_fill(&mut crate::rand::rng()).unwrap()
+    }
+}
+
+impl<const N: usize> Randomize for Public<N> {
+    fn try_fill<R: Rng + ?Sized>(&mut self, rng: &mut R) -> Result<(), rand::Error> {
+        self.value.try_fill(rng)
+    }
+}
+
+impl<const N: usize> fmt::Debug for Public<N> {
+    fn fmt(&self, fmt: &mut fmt::Formatter) -> fmt::Result {
+        debug_crypto_array(&self.value, fmt)
+    }
+}
+
+impl<const N: usize> Deref for Public<N> {
+    type Target = [u8; N];
+
+    fn deref(&self) -> &[u8; N] {
+        &self.value
+    }
+}
+
+impl<const N: usize> DerefMut for Public<N> {
+    fn deref_mut(&mut self) -> &mut [u8; N] {
+        &mut self.value
+    }
+}
+
+impl<const N: usize> Borrow<[u8; N]> for Public<N> {
+    fn borrow(&self) -> &[u8; N] {
+        &self.value
+    }
+}
+impl<const N: usize> BorrowMut<[u8; N]> for Public<N> {
+    fn borrow_mut(&mut self) -> &mut [u8; N] {
+        &mut self.value
+    }
+}
+
+impl<const N: usize> Borrow<[u8]> for Public<N> {
+    fn borrow(&self) -> &[u8] {
+        &self.value
+    }
+}
+impl<const N: usize> BorrowMut<[u8]> for Public<N> {
+    fn borrow_mut(&mut self) -> &mut [u8] {
+        &mut self.value
+    }
+}
+
+impl<const N: usize> LoadValue for Public<N> {
+    type Error = anyhow::Error;
+
+    fn load<P: AsRef<Path>>(path: P) -> anyhow::Result<Self> {
+        let mut v = Self::random();
+        fopen_r(path)?.read_exact_to_end(&mut *v)?;
+        Ok(v)
+    }
+}
+
+impl<const N: usize> StoreValue for Public<N> {
+    type Error = anyhow::Error;
+
+    fn store<P: AsRef<Path>>(&self, path: P) -> anyhow::Result<()> {
+        std::fs::write(path, **self)?;
+        Ok(())
+    }
+}

secret-memory/src/rand.rs

@@ -0,0 +1,5 @@
+pub type Rng = rand::rngs::ThreadRng;
+
+pub fn rng() -> Rng {
+    rand::thread_rng()
+}

secret-memory/src/secret.rs

@@ -0,0 +1,321 @@
+use std::cell::RefCell;
+use std::collections::HashMap;
+use std::convert::TryInto;
+use std::fmt;
+use std::ops::{Deref, DerefMut};
+use std::path::Path;
+
+use anyhow::Context;
+use rand::{Fill as Randomize, Rng};
+use zeroize::{Zeroize, ZeroizeOnDrop};
+
+use rosenpass_util::b64::b64_reader;
+use rosenpass_util::file::{fopen_r, LoadValue, LoadValueB64, ReadExactToEnd};
+use rosenpass_util::functional::mutating;
+
+use crate::alloc::{secret_box, SecretBox, SecretVec};
+use crate::file::StoreSecret;
+
+// This might become a problem in library usage; it's effectively a memory
+// leak which probably isn't a problem right now because most memory will
+// be reused…
+thread_local! {
+    static SECRET_CACHE: RefCell<SecretMemoryPool> = RefCell::new(SecretMemoryPool::new());
+}
+
+fn with_secret_memory_pool<Fn, R>(mut f: Fn) -> R
+where
+    Fn: FnMut(Option<&mut SecretMemoryPool>) -> R,
+{
+    // This acquires the SECRET_CACHE
+    SECRET_CACHE
+        .try_with(|cell| {
+            // And acquires the inner reference
+            cell.try_borrow_mut()
+                .as_deref_mut()
+                // To call the given function
+                .map(|pool| f(Some(pool)))
+                .ok()
+        })
+        .ok()
+        .flatten()
+        // Failing that, the given function is called with None
+        .unwrap_or_else(|| f(None))
+}
+
+// Wrapper around SecretBox that applies automatic zeroization
+#[derive(Debug)]
+struct ZeroizingSecretBox<T: Zeroize + ?Sized>(Option<SecretBox<T>>);
+
+impl<T: Zeroize> ZeroizingSecretBox<T> {
+    fn new(boxed: T) -> Self {
+        ZeroizingSecretBox(Some(secret_box(boxed)))
+    }
+}
+
+impl<T: Zeroize + ?Sized> ZeroizingSecretBox<T> {
+    fn from_secret_box(inner: SecretBox<T>) -> Self {
+        Self(Some(inner))
+    }
+
+    fn take(mut self) -> SecretBox<T> {
+        self.0.take().unwrap()
+    }
+}
+
+impl<T: Zeroize + ?Sized> ZeroizeOnDrop for ZeroizingSecretBox<T> {}
+impl<T: Zeroize + ?Sized> Zeroize for ZeroizingSecretBox<T> {
+    fn zeroize(&mut self) {
+        if let Some(inner) = &mut self.0 {
+            let inner: &mut SecretBox<T> = inner; // type annotation
+            inner.zeroize()
+        }
+    }
+}
+
+impl<T: Zeroize + ?Sized> Drop for ZeroizingSecretBox<T> {
+    fn drop(&mut self) {
+        self.zeroize()
+    }
+}
+
+impl<T: Zeroize + ?Sized> Deref for ZeroizingSecretBox<T> {
+    type Target = T;
+
+    fn deref(&self) -> &T {
+        self.0.as_ref().unwrap()
+    }
+}
+
+impl<T: Zeroize + ?Sized> DerefMut for ZeroizingSecretBox<T> {
+    fn deref_mut(&mut self) -> &mut T {
+        self.0.as_mut().unwrap()
+    }
+}
+
+/// Pool that stores secret memory allocations
+///
+/// Allocation of secret memory is expensive. Thus, this struct provides a
+/// pool of secret memory, readily available to yield protected, slices of
+/// memory.
+#[derive(Debug)] // TODO check on Debug derive, is that clever
+struct SecretMemoryPool {
+    pool: HashMap<usize, Vec<ZeroizingSecretBox<[u8]>>>,
+}
+
+impl SecretMemoryPool {
+    /// Create a new [SecretMemoryPool]
+    #[allow(clippy::new_without_default)]
+    pub fn new() -> Self {
+        Self {
+            pool: HashMap::new(),
+        }
+    }
+
+    /// Return secret back to the pool for future re-use
+    pub fn release<const N: usize>(&mut self, mut sec: ZeroizingSecretBox<[u8; N]>) {
+        sec.zeroize();
+
+        // This conversion sequence is weird but at least it guarantees
+        // that the heap allocation is preserved according to the docs
+        let sec: SecretVec<u8> = sec.take().into();
+        let sec: SecretBox<[u8]> = sec.into();
+
+        self.pool
+            .entry(N)
+            .or_default()
+            .push(ZeroizingSecretBox::from_secret_box(sec));
+    }
+
+    /// Take protected memory from the pool, allocating new one if no suitable
+    /// chunk is found in the inventory.
+    ///
+    /// The secret is guaranteed to be full of nullbytes
+    pub fn take<const N: usize>(&mut self) -> ZeroizingSecretBox<[u8; N]> {
+        let entry = self.pool.entry(N).or_default();
+        let inner = match entry.pop() {
+            None => secret_box([0u8; N]),
+            Some(sec) => sec.take().try_into().unwrap(),
+        };
+        ZeroizingSecretBox::from_secret_box(inner)
+    }
+}
+
+/// Storage for secret data
+pub struct Secret<const N: usize> {
+    storage: Option<ZeroizingSecretBox<[u8; N]>>,
+}
+
+impl<const N: usize> Secret<N> {
+    pub fn from_slice(slice: &[u8]) -> Self {
+        let mut new_self = Self::zero();
+        new_self.secret_mut().copy_from_slice(slice);
+        new_self
+    }
+
+    /// Returns a new [Secret] that is zero initialized
+    pub fn zero() -> Self {
+        // Using [SecretMemoryPool] here because this operation is expensive,
+        // yet it is used in hot loops
+        let buf = with_secret_memory_pool(|pool| {
+            pool.map(|p| p.take())
+                .unwrap_or_else(|| ZeroizingSecretBox::new([0u8; N]))
+        });
+
+        Self { storage: Some(buf) }
+    }
+
+    /// Returns a new [Secret] that is randomized
+    pub fn random() -> Self {
+        mutating(Self::zero(), |r| r.randomize())
+    }
+
+    /// Sets all data an existing secret to random bytes
+    pub fn randomize(&mut self) {
+        self.try_fill(&mut crate::rand::rng()).unwrap()
+    }
+
+    /// Borrows the data
+    pub fn secret(&self) -> &[u8; N] {
+        self.storage.as_ref().unwrap()
+    }
+
+    /// Borrows the data mutably
+    pub fn secret_mut(&mut self) -> &mut [u8; N] {
+        self.storage.as_mut().unwrap()
+    }
+}
+
+impl<const N: usize> Randomize for Secret<N> {
+    fn try_fill<R: Rng + ?Sized>(&mut self, rng: &mut R) -> Result<(), rand::Error> {
+        // Zeroize self first just to make sure the barriers from the zeroize create take
+        // effect to prevent the compiler from optimizing this away.
+        // We should at some point replace this with our own barriers.
+        self.zeroize();
+        self.secret_mut().try_fill(rng)
+    }
+}
+
+impl<const N: usize> ZeroizeOnDrop for Secret<N> {}
+impl<const N: usize> Zeroize for Secret<N> {
+    fn zeroize(&mut self) {
+        if let Some(inner) = &mut self.storage {
+            inner.zeroize()
+        }
+    }
+}
+
+impl<const N: usize> Drop for Secret<N> {
+    fn drop(&mut self) {
+        with_secret_memory_pool(|pool| {
+            if let Some((pool, secret)) = pool.zip(self.storage.take()) {
+                pool.release(secret);
+            }
+        });
+
+        // This should be unnecessary: The pool has one item – the inner secret – which
+        // zeroizes itself on drop. Calling it should not do any harm though…
+        self.zeroize()
+    }
+}
+
+impl<const N: usize> Clone for Secret<N> {
+    fn clone(&self) -> Self {
+        Self::from_slice(self.secret())
+    }
+}
+
+/// The Debug implementation of [Secret] does not reveal the secret data,
+/// instead a placeholder `<SECRET>` is used
+impl<const N: usize> fmt::Debug for Secret<N> {
+    fn fmt(&self, fmt: &mut fmt::Formatter) -> fmt::Result {
+        fmt.write_str("<SECRET>")
+    }
+}
+
+impl<const N: usize> LoadValue for Secret<N> {
+    type Error = anyhow::Error;
+
+    fn load<P: AsRef<Path>>(path: P) -> anyhow::Result<Self> {
+        let mut v = Self::random();
+        let p = path.as_ref();
+        fopen_r(p)?
+            .read_exact_to_end(v.secret_mut())
+            .with_context(|| format!("Could not load file {p:?}"))?;
+        Ok(v)
+    }
+}
+
+impl<const N: usize> LoadValueB64 for Secret<N> {
+    type Error = anyhow::Error;
+
+    fn load_b64<P: AsRef<Path>>(path: P) -> anyhow::Result<Self> {
+        use std::io::Read;
+
+        let mut v = Self::random();
+        let p = path.as_ref();
+        // This might leave some fragments of the secret on the stack;
+        // in practice this is likely not a problem because the stack likely
+        // will be overwritten by something else soon but this is not exactly
+        // guaranteed. It would be possible to remedy this, but since the secret
+        // data will linger in the Linux page cache anyways with the current
+        // implementation, going to great length to erase the secret here is
+        // not worth it right now.
+        b64_reader(&mut fopen_r(p)?)
+            .read_exact(v.secret_mut())
+            .with_context(|| format!("Could not load base64 file {p:?}"))?;
+        Ok(v)
+    }
+}
+
+impl<const N: usize> StoreSecret for Secret<N> {
+    type Error = anyhow::Error;
+
+    fn store_secret<P: AsRef<Path>>(&self, path: P) -> anyhow::Result<()> {
+        std::fs::write(path, self.secret())?;
+        Ok(())
+    }
+}
+
+#[cfg(test)]
+mod test {
+    use super::*;
+
+    /// check that we can alloc using the magic pool
+    #[test]
+    fn secret_memory_pool_take() {
+        const N: usize = 0x100;
+        let mut pool = SecretMemoryPool::new();
+        let secret: ZeroizingSecretBox<[u8; N]> = pool.take();
+        assert_eq!(secret.as_ref(), &[0; N]);
+    }
+
+    /// check that a secrete lives, even if its [SecretMemoryPool] is deleted
+    #[test]
+    fn secret_memory_pool_drop() {
+        const N: usize = 0x100;
+        let mut pool = SecretMemoryPool::new();
+        let secret: ZeroizingSecretBox<[u8; N]> = pool.take();
+        std::mem::drop(pool);
+        assert_eq!(secret.as_ref(), &[0; N]);
+    }
+
+    /// check that a secrete can be reborn, freshly initialized with zero
+    #[test]
+    fn secret_memory_pool_release() {
+        const N: usize = 1;
+        let mut pool = SecretMemoryPool::new();
+        let mut secret: ZeroizingSecretBox<[u8; N]> = pool.take();
+        let old_secret_ptr = secret.as_ref().as_ptr();
+
+        secret.as_mut()[0] = 0x13;
+        pool.release(secret);
+
+        // now check that we get the same ptr
+        let new_secret: ZeroizingSecretBox<[u8; N]> = pool.take();
+        assert_eq!(old_secret_ptr, new_secret.as_ref().as_ptr());
+
+        // and that the secret was zeroized
+        assert_eq!(new_secret.as_ref(), &[0; N]);
+    }
+}

sodium/src/aead/chacha20poly1305_ietf.rs

@@ -1,63 +0,0 @@
-use libsodium_sys as libsodium;
-use std::ffi::c_ulonglong;
-use std::ptr::{null, null_mut};
-
-pub const KEY_LEN: usize = libsodium::crypto_aead_chacha20poly1305_IETF_KEYBYTES as usize;
-pub const TAG_LEN: usize = libsodium::crypto_aead_chacha20poly1305_IETF_ABYTES as usize;
-pub const NONCE_LEN: usize = libsodium::crypto_aead_chacha20poly1305_IETF_NPUBBYTES as usize;
-
-#[inline]
-pub fn encrypt(
-    ciphertext: &mut [u8],
-    key: &[u8],
-    nonce: &[u8],
-    ad: &[u8],
-    plaintext: &[u8],
-) -> anyhow::Result<()> {
-    assert!(ciphertext.len() == plaintext.len() + TAG_LEN);
-    assert!(key.len() == KEY_LEN);
-    assert!(nonce.len() == NONCE_LEN);
-    let mut clen: u64 = 0;
-    sodium_call!(
-        crypto_aead_chacha20poly1305_ietf_encrypt,
-        ciphertext.as_mut_ptr(),
-        &mut clen,
-        plaintext.as_ptr(),
-        plaintext.len() as c_ulonglong,
-        ad.as_ptr(),
-        ad.len() as c_ulonglong,
-        null(), // nsec is not used
-        nonce.as_ptr(),
-        key.as_ptr()
-    )?;
-    assert!(clen as usize == ciphertext.len());
-    Ok(())
-}
-
-#[inline]
-pub fn decrypt(
-    plaintext: &mut [u8],
-    key: &[u8],
-    nonce: &[u8],
-    ad: &[u8],
-    ciphertext: &[u8],
-) -> anyhow::Result<()> {
-    assert!(ciphertext.len() == plaintext.len() + TAG_LEN);
-    assert!(key.len() == KEY_LEN);
-    assert!(nonce.len() == NONCE_LEN);
-    let mut mlen: u64 = 0;
-    sodium_call!(
-        crypto_aead_chacha20poly1305_ietf_decrypt,
-        plaintext.as_mut_ptr(),
-        &mut mlen as *mut c_ulonglong,
-        null_mut(), // nsec is not used
-        ciphertext.as_ptr(),
-        ciphertext.len() as c_ulonglong,
-        ad.as_ptr(),
-        ad.len() as c_ulonglong,
-        nonce.as_ptr(),
-        key.as_ptr()
-    )?;
-    assert!(mlen as usize == plaintext.len());
-    Ok(())
-}

sodium/src/aead/mod.rs

@@ -1,2 +0,0 @@
-pub mod chacha20poly1305_ietf;
-pub mod xchacha20poly1305_ietf;

sodium/src/aead/xchacha20poly1305_ietf.rs

@@ -1,63 +0,0 @@
-use libsodium_sys as libsodium;
-use std::ffi::c_ulonglong;
-use std::ptr::{null, null_mut};
-
-pub const KEY_LEN: usize = libsodium::crypto_aead_xchacha20poly1305_IETF_KEYBYTES as usize;
-pub const TAG_LEN: usize = libsodium::crypto_aead_xchacha20poly1305_ietf_ABYTES as usize;
-pub const NONCE_LEN: usize = libsodium::crypto_aead_xchacha20poly1305_IETF_NPUBBYTES as usize;
-
-#[inline]
-pub fn encrypt(
-    ciphertext: &mut [u8],
-    key: &[u8],
-    nonce: &[u8],
-    ad: &[u8],
-    plaintext: &[u8],
-) -> anyhow::Result<()> {
-    assert!(ciphertext.len() == plaintext.len() + NONCE_LEN + TAG_LEN);
-    assert!(key.len() == libsodium::crypto_aead_xchacha20poly1305_IETF_KEYBYTES as usize);
-    let (n, ct) = ciphertext.split_at_mut(NONCE_LEN);
-    n.copy_from_slice(nonce);
-    let mut clen: u64 = 0;
-    sodium_call!(
-        crypto_aead_xchacha20poly1305_ietf_encrypt,
-        ct.as_mut_ptr(),
-        &mut clen,
-        plaintext.as_ptr(),
-        plaintext.len() as c_ulonglong,
-        ad.as_ptr(),
-        ad.len() as c_ulonglong,
-        null(), // nsec is not used
-        nonce.as_ptr(),
-        key.as_ptr()
-    )?;
-    assert!(clen as usize == ct.len());
-    Ok(())
-}
-
-#[inline]
-pub fn decrypt(
-    plaintext: &mut [u8],
-    key: &[u8],
-    ad: &[u8],
-    ciphertext: &[u8],
-) -> anyhow::Result<()> {
-    assert!(ciphertext.len() == plaintext.len() + NONCE_LEN + TAG_LEN);
-    assert!(key.len() == KEY_LEN);
-    let (n, ct) = ciphertext.split_at(NONCE_LEN);
-    let mut mlen: u64 = 0;
-    sodium_call!(
-        crypto_aead_xchacha20poly1305_ietf_decrypt,
-        plaintext.as_mut_ptr(),
-        &mut mlen as *mut c_ulonglong,
-        null_mut(), // nsec is not used
-        ct.as_ptr(),
-        ct.len() as c_ulonglong,
-        ad.as_ptr(),
-        ad.len() as c_ulonglong,
-        n.as_ptr(),
-        key.as_ptr()
-    )?;
-    assert!(mlen as usize == plaintext.len());
-    Ok(())
-}

sodium/src/hash/blake2b.rs

@@ -1,31 +0,0 @@
-use libsodium_sys as libsodium;
-use rosenpass_to::{with_destination, To};
-use std::ffi::c_ulonglong;
-use std::ptr::null;
-
-pub const KEY_MIN: usize = libsodium::crypto_generichash_blake2b_KEYBYTES_MIN as usize;
-pub const KEY_MAX: usize = libsodium::crypto_generichash_blake2b_KEYBYTES_MAX as usize;
-pub const OUT_MIN: usize = libsodium::crypto_generichash_blake2b_BYTES_MIN as usize;
-pub const OUT_MAX: usize = libsodium::crypto_generichash_blake2b_BYTES_MAX as usize;
-
-#[inline]
-pub fn hash<'a>(key: &'a [u8], data: &'a [u8]) -> impl To<[u8], anyhow::Result<()>> + 'a {
-    with_destination(|out: &mut [u8]| {
-        assert!(key.is_empty() || (KEY_MIN <= key.len() && key.len() <= KEY_MAX));
-        assert!(OUT_MIN <= out.len() && out.len() <= OUT_MAX);
-        let kptr = match key.len() {
-            // NULL key
-            0 => null(),
-            _ => key.as_ptr(),
-        };
-        sodium_call!(
-            crypto_generichash_blake2b,
-            out.as_mut_ptr(),
-            out.len(),
-            data.as_ptr(),
-            data.len() as c_ulonglong,
-            kptr,
-            key.len()
-        )
-    })
-}

sodium/src/hash/mod.rs

@@ -1 +0,0 @@
-pub mod blake2b;

sodium/src/helpers.rs

@@ -1,52 +0,0 @@
-use libsodium_sys as libsodium;
-use std::os::raw::c_void;
-
-#[inline]
-pub fn memcmp(a: &[u8], b: &[u8]) -> bool {
-    a.len() == b.len()
-        && unsafe {
-            let r = libsodium::sodium_memcmp(
-                a.as_ptr() as *const c_void,
-                b.as_ptr() as *const c_void,
-                a.len(),
-            );
-            r == 0
-        }
-}
-
-#[inline]
-pub fn compare(a: &[u8], b: &[u8]) -> i32 {
-    assert!(a.len() == b.len());
-    unsafe { libsodium::sodium_compare(a.as_ptr(), b.as_ptr(), a.len()) }
-}
-
-#[inline]
-pub fn increment(v: &mut [u8]) {
-    unsafe {
-        libsodium::sodium_increment(v.as_mut_ptr(), v.len());
-    }
-}
-
-#[inline]
-pub fn randombytes_buf(buf: &mut [u8]) {
-    unsafe { libsodium::randombytes_buf(buf.as_mut_ptr() as *mut c_void, buf.len()) };
-}
-
-#[inline]
-pub fn memzero(buf: &mut [u8]) {
-    unsafe { libsodium::sodium_memzero(buf.as_mut_ptr() as *mut c_void, buf.len()) };
-}
-
-// Choose a fully random u64
-// TODO: Replace with ::rand::random
-pub fn rand_u64() -> u64 {
-    let mut buf = [0u8; 8];
-    randombytes_buf(&mut buf);
-    u64::from_le_bytes(buf)
-}
-
-// Choose a random f64 in [0; 1] inclusive; quick and dirty
-// TODO: Replace with ::rand::random
-pub fn rand_f64() -> f64 {
-    (rand_u64() as f64) / (u64::MAX as f64)
-}

sodium/src/lib.rs

@@ -1,20 +0,0 @@
-use libsodium_sys as libsodium;
-
-macro_rules! sodium_call {
-    ($name:ident, $($args:expr),*) => { ::rosenpass_util::attempt!({
-        anyhow::ensure!(unsafe{libsodium::$name($($args),*)} > -1,
-            "Error in libsodium's {}.", stringify!($name));
-        Ok(())
-    })};
-    ($name:ident) => { sodium_call!($name, ) };
-}
-
-#[inline]
-pub fn init() -> anyhow::Result<()> {
-    log::trace!("initializing libsodium");
-    sodium_call!(sodium_init)
-}
-
-pub mod aead;
-pub mod hash;
-pub mod helpers;

to/README.md

@@ -12,15 +12,17 @@ The crate provides chained functions to simplify allocating the destination para
 For now this crate is experimental; patch releases are guaranteed not to contain any breaking changes, but minor releases may.
 
 ```rust
-use std::ops::BitXorAssign;
-use rosenpass_to::{To, to, with_destination};
 use rosenpass_to::ops::copy_array;
+use rosenpass_to::{to, with_destination, To};
+use std::ops::BitXorAssign;
 
 // Destination functions return some value that implements the To trait.
 // Unfortunately dealing with lifetimes is a bit more finicky than it would#
 // be without destination parameters
-fn xor_slice<'a, T>(src: &'a[T]) -> impl To<[T], ()> + 'a
-        where T: BitXorAssign + Clone {
+fn xor_slice<'a, T>(src: &'a [T]) -> impl To<[T], ()> + 'a
+where
+    T: BitXorAssign + Clone,
+{
     // Custom implementations of the to trait can be created, but the easiest
     with_destination(move |dst: &mut [T]| {
         assert!(src.len() == dst.len());
@@ -65,7 +67,7 @@ assert_eq!(&dst[..], &flip01[..]);
 // The builtin function copy_array supports to_value() since its
 // destination parameter is a fixed size array, which can be allocated
 // using default()
-let dst : [u8; 4] = copy_array(flip01).to_value();
+let dst: [u8; 4] = copy_array(flip01).to_value();
 assert_eq!(&dst, flip01);
 ```
 
@@ -84,7 +86,9 @@ Functions declared like this are more cumbersome to use when the destination par
 use std::ops::BitXorAssign;
 
 fn xor_slice<T>(dst: &mut [T], src: &[T])
-        where T: BitXorAssign + Clone {
+where
+    T: BitXorAssign + Clone,
+{
     assert!(src.len() == dst.len());
     for (d, s) in dst.iter_mut().zip(src.iter()) {
         *d ^= s.clone();
@@ -114,8 +118,8 @@ assert_eq!(&dst[..], &flip01[..]);
 There are a couple of ways to use a function with destination:
 
 ```rust
-use rosenpass_to::{to, To};
 use rosenpass_to::ops::{copy_array, copy_slice_least};
+use rosenpass_to::{to, To};
 
 let mut dst = b"           ".to_vec();
 
@@ -129,7 +133,8 @@ copy_slice_least(b"This is fin").to(&mut dst[..]);
 assert_eq!(&dst[..], b"This is fin");
 
 // You can allocate the destination variable on the fly using `.to_this(...)`
-let tmp = copy_slice_least(b"This is new---").to_this(|| b"This will be overwritten".to_owned());
+let tmp =
+    copy_slice_least(b"This is new---").to_this(|| b"This will be overwritten".to_owned());
 assert_eq!(&tmp[..], b"This is new---verwritten");
 
 // You can allocate the destination variable on the fly `.collect(..)` if it implements default
@@ -147,8 +152,11 @@ assert_eq!(&tmp[..], b"Fixed");
 The to crate provides basic functions with destination for copying data between slices and arrays.
 
 ```rust
+use rosenpass_to::ops::{
+    copy_array, copy_slice, copy_slice_least, copy_slice_least_src, try_copy_slice,
+    try_copy_slice_least_src,
+};
 use rosenpass_to::{to, To};
-use rosenpass_to::ops::{copy_array, copy_slice, copy_slice_least, copy_slice_least_src, try_copy_slice, try_copy_slice_least_src};
 
 let mut dst = b"           ".to_vec();
 
@@ -161,18 +169,33 @@ to(&mut dst[4..], copy_slice_least_src(b"!!!"));
 assert_eq!(&dst[..], b"Hell!!!orld");
 
 // Copy a slice, copying as many bytes as possible
-to(&mut dst[6..], copy_slice_least(b"xxxxxxxxxxxxxxxxxxxxxxxxxxxxx"));
+to(
+    &mut dst[6..],
+    copy_slice_least(b"xxxxxxxxxxxxxxxxxxxxxxxxxxxxx"),
+);
 assert_eq!(&dst[..], b"Hell!!xxxxx");
 
 // Copy a slice, will return None and abort if the sizes do not much
 assert_eq!(Some(()), to(&mut dst[..], try_copy_slice(b"Hello World")));
 assert_eq!(None, to(&mut dst[..], try_copy_slice(b"---")));
-assert_eq!(None, to(&mut dst[..], try_copy_slice(b"---------------------")));
+assert_eq!(
+    None,
+    to(&mut dst[..], try_copy_slice(b"---------------------"))
+);
 assert_eq!(&dst[..], b"Hello World");
 
 // Copy a slice, will return None and abort if source is longer than destination
-assert_eq!(Some(()), to(&mut dst[4..], try_copy_slice_least_src(b"!!!")));
-assert_eq!(None, to(&mut dst[4..], try_copy_slice_least_src(b"-------------------------")));
+assert_eq!(
+    Some(()),
+    to(&mut dst[4..], try_copy_slice_least_src(b"!!!"))
+);
+assert_eq!(
+    None,
+    to(
+        &mut dst[4..],
+        try_copy_slice_least_src(b"-------------------------")
+    )
+);
 assert_eq!(&dst[..], b"Hell!!!orld");
 
 // Copy fixed size arrays all at once
@@ -186,12 +209,14 @@ assert_eq!(&dst, b"Hello");
 The easiest way to declare a function with destination is to use the with_destination function.
 
 ```rust
-use rosenpass_to::{To, to, with_destination};
 use rosenpass_to::ops::copy_array;
+use rosenpass_to::{to, with_destination, To};
 
 /// Copy the given slice to the start of a vector, reusing its memory if possible
 fn copy_to_vec<'a, T>(src: &'a [T]) -> impl To<Vec<T>, ()> + 'a
-        where T: Clone {
+where
+    T: Clone,
+{
     with_destination(move |dst: &mut Vec<T>| {
         dst.clear();
         dst.extend_from_slice(src);
@@ -217,7 +242,9 @@ The same pattern can be implemented without `to`, at the cost of being slightly
 ```rust
 /// Copy the given slice to the start of a vector, reusing its memory if possible
 fn copy_to_vec<T>(dst: &mut Vec<T>, src: &[T])
-        where T: Clone {
+where
+    T: Clone,
+{
     dst.clear();
     dst.extend_from_slice(src);
 }
@@ -240,11 +267,11 @@ Alternative functions are returned, that return a `to::Beside` value, containing
 destination variable and the return value.
 
 ```rust
-use std::cmp::{min, max};
-use rosenpass_to::{To, to, with_destination, Beside};
+use rosenpass_to::{to, with_destination, Beside, To};
+use std::cmp::{max, min};
 
 /// Copy an array of floats and calculate the average
-pub fn copy_and_average<'a>(src: &'a[f64]) -> impl To<[f64], f64> + 'a {
+pub fn copy_and_average<'a>(src: &'a [f64]) -> impl To<[f64], f64> + 'a {
     with_destination(move |dst: &mut [f64]| {
         assert!(src.len() == dst.len());
         let mut sum = 0f64;
@@ -300,8 +327,8 @@ assert_eq!(tmp, Beside([42f64; 3], 42f64));
 When Beside values contain a `()`, `Option<()>`, or `Result<(), Error>` return value, they expose a special method called `.condense()`; this method consumes the Beside value and condenses destination and return value into one value.
 
 ```rust
+use rosenpass_to::Beside;
 use std::result::Result;
-use rosenpass_to::{Beside};
 
 assert_eq!((), Beside((), ()).condense());
 
@@ -318,8 +345,8 @@ assert_eq!(Err(()), Beside(42, err_unit).condense());
 When condense is implemented for a type, `.to_this(|| ...)`, `.to_value()`, and `.collect::<...>()` on the `To` trait can be used even with a return value:
 
 ```rust
+use rosenpass_to::ops::try_copy_slice;
 use rosenpass_to::To;
-use rosenpass_to::ops::try_copy_slice;;
 
 let tmp = try_copy_slice(b"Hello World").collect::<[u8; 11]>();
 assert_eq!(tmp, Some(*b"Hello World"));
@@ -337,8 +364,8 @@ assert_eq!(tmp, None);
 The same naturally also works for Results, but the example is a bit harder to motivate:
 
 ```rust
+use rosenpass_to::{to, with_destination, To};
 use std::result::Result;
-use rosenpass_to::{to, To, with_destination};
 
 #[derive(PartialEq, Eq, Debug, Default)]
 struct InvalidFloat;
@@ -380,8 +407,8 @@ Condensation is implemented through a trait called CondenseBeside ([local](Conde
 If you can not implement this trait because its for an external type (see [orphan rule](https://doc.rust-lang.org/book/ch10-02-traits.html#implementing-a-trait-on-a-type)), this crate welcomes contributions of new Condensation rules.
 
 ```rust
-use rosenpass_to::{To, with_destination, Beside, CondenseBeside};
 use rosenpass_to::ops::copy_slice;
+use rosenpass_to::{with_destination, Beside, CondenseBeside, To};
 
 #[derive(PartialEq, Eq, Debug, Default)]
 struct MyTuple<Left, Right>(Left, Right);
@@ -396,7 +423,10 @@ impl<Val, Right> CondenseBeside<Val> for MyTuple<(), Right> {
 }
 
 fn copy_slice_and_return_something<'a, T, U>(src: &'a [T], something: U) -> impl To<[T], U> + 'a
-        where T: Copy, U: 'a {
+where
+    T: Copy,
+    U: 'a,
+{
     with_destination(move |dst: &mut [T]| {
         copy_slice(src).to(dst);
         something
@@ -417,7 +447,7 @@ Using `with_destination(...)` is convenient, but since it uses closures it resul
 Implementing the ToTrait manual is the right choice for library use cases.
 
 ```rust
-use rosenpass_to::{to, To, with_destination};
+use rosenpass_to::{to, with_destination, To};
 
 struct TryCopySliceSource<'a, T: Copy> {
     src: &'a [T],
@@ -425,17 +455,20 @@ struct TryCopySliceSource<'a, T: Copy> {
 
 impl<'a, T: Copy> To<[T], Option<()>> for TryCopySliceSource<'a, T> {
     fn to(self, dst: &mut [T]) -> Option<()> {
-        (self.src.len() == dst.len())
-            .then(|| dst.copy_from_slice(self.src))
+        (self.src.len() == dst.len()).then(|| dst.copy_from_slice(self.src))
     }
 }
 
 fn try_copy_slice<'a, T>(src: &'a [T]) -> TryCopySliceSource<'a, T>
-        where T: Copy {
+where
+    T: Copy,
+{
     TryCopySliceSource { src }
 }
 
-let mut dst = try_copy_slice(b"Hello World").collect::<[u8; 11]>().unwrap();
+let mut dst = try_copy_slice(b"Hello World")
+    .collect::<[u8; 11]>()
+    .unwrap();
 assert_eq!(&dst[..], b"Hello World");
 assert_eq!(None, to(&mut dst[..], try_copy_slice(b"---")));
 ```
@@ -445,8 +478,8 @@ assert_eq!(None, to(&mut dst[..], try_copy_slice(b"---")));
 Destinations can also be used with methods. This example demonstrates using destinations in an extension trait for everything that implements `Borrow<[T]>` for any `T` and a concrete `To` trait implementation.
 
 ```rust
+use rosenpass_to::{to, with_destination, To};
 use std::borrow::Borrow;
-use rosenpass_to::{to, To, with_destination};
 
 struct TryCopySliceSource<'a, T: Copy> {
     src: &'a [T],
@@ -454,24 +487,24 @@ struct TryCopySliceSource<'a, T: Copy> {
 
 impl<'a, T: Copy> To<[T], Option<()>> for TryCopySliceSource<'a, T> {
     fn to(self, dst: &mut [T]) -> Option<()> {
-        (self.src.len() == dst.len())
-            .then(|| dst.copy_from_slice(self.src))
+        (self.src.len() == dst.len()).then(|| dst.copy_from_slice(self.src))
     }
 }
 
 trait TryCopySliceExt<'a, T: Copy> {
-    fn try_copy_slice(&'a self)  -> TryCopySliceSource<'a, T>;
+    fn try_copy_slice(&'a self) -> TryCopySliceSource<'a, T>;
 }
 
 impl<'a, T: 'a + Copy, Ref: 'a + Borrow<[T]>> TryCopySliceExt<'a, T> for Ref {
-    fn try_copy_slice(&'a self)  -> TryCopySliceSource<'a, T> {
-        TryCopySliceSource {
-            src: self.borrow()
-        }
+    fn try_copy_slice(&'a self) -> TryCopySliceSource<'a, T> {
+        TryCopySliceSource { src: self.borrow() }
     }
 }
 
-let mut dst = b"Hello World".try_copy_slice().collect::<[u8; 11]>().unwrap();
+let mut dst = b"Hello World"
+    .try_copy_slice()
+    .collect::<[u8; 11]>()
+    .unwrap();
 assert_eq!(&dst[..], b"Hello World");
 assert_eq!(None, to(&mut dst[..], b"---".try_copy_slice()));
 ```

to/src/ops.rs

@@ -8,7 +8,7 @@ use crate::{with_destination, To};
 /// # Panics
 ///
 /// This function will panic if the two slices have different lengths.
-pub fn copy_slice<'a, T>(origin: &'a [T]) -> impl To<[T], ()> + 'a
+pub fn copy_slice<T>(origin: &[T]) -> impl To<[T], ()> + '_
 where
     T: Copy,
 {
@@ -23,7 +23,7 @@ where
 /// # Panics
 ///
 /// This function will panic if destination is shorter than origin.
-pub fn copy_slice_least_src<'a, T>(origin: &'a [T]) -> impl To<[T], ()> + 'a
+pub fn copy_slice_least_src<T>(origin: &[T]) -> impl To<[T], ()> + '_
 where
     T: Copy,
 {
@@ -34,7 +34,7 @@ where
 /// destination.
 ///
 /// Copies as much data as is present in the shorter slice.
-pub fn copy_slice_least<'a, T>(origin: &'a [T]) -> impl To<[T], ()> + 'a
+pub fn copy_slice_least<T>(origin: &[T]) -> impl To<[T], ()> + '_
 where
     T: Copy,
 {
@@ -47,7 +47,7 @@ where
 /// Function with destination that attempts to copy data from origin into the destination.
 ///
 /// Will return None if the slices are of different lengths.
-pub fn try_copy_slice<'a, T>(origin: &'a [T]) -> impl To<[T], Option<()>> + 'a
+pub fn try_copy_slice<T>(origin: &[T]) -> impl To<[T], Option<()>> + '_
 where
     T: Copy,
 {
@@ -62,7 +62,7 @@ where
 /// Destination may be longer than origin.
 ///
 /// Will return None if the destination is shorter than origin.
-pub fn try_copy_slice_least_src<'a, T>(origin: &'a [T]) -> impl To<[T], Option<()>> + 'a
+pub fn try_copy_slice_least_src<T>(origin: &[T]) -> impl To<[T], Option<()>> + '_
 where
     T: Copy,
 {
@@ -72,7 +72,7 @@ where
 }
 
 /// Function with destination that copies all data between two array references.
-pub fn copy_array<'a, T, const N: usize>(origin: &'a [T; N]) -> impl To<[T; N], ()> + 'a
+pub fn copy_array<T, const N: usize>(origin: &[T; N]) -> impl To<[T; N], ()> + '_
 where
     T: Copy,
 {

util/Cargo.toml

@@ -14,3 +14,5 @@ readme = "readme.md"
 [dependencies]
 base64 = { workspace = true }
 anyhow = { workspace = true }
+typenum = { workspace = true }
+static_assertions = { workspace = true }

util/src/file.rs

@@ -6,21 +6,21 @@ use std::{fs::OpenOptions, path::Path};
 
 /// Open a file writable
 pub fn fopen_w<P: AsRef<Path>>(path: P) -> std::io::Result<File> {
-    Ok(OpenOptions::new()
+    OpenOptions::new()
         .read(false)
         .write(true)
         .create(true)
         .truncate(true)
-        .open(path)?)
+        .open(path)
 }
 /// Open a file readable
 pub fn fopen_r<P: AsRef<Path>>(path: P) -> std::io::Result<File> {
-    Ok(OpenOptions::new()
+    OpenOptions::new()
         .read(true)
         .write(false)
         .create(false)
         .truncate(false)
-        .open(path)?)
+        .open(path)
 }
 
 pub trait ReadExactToEnd {

util/src/lib.rs

@@ -1,7 +1,11 @@
+#![recursion_limit = "256"]
+
 pub mod b64;
+pub mod fd;
 pub mod file;
 pub mod functional;
 pub mod mem;
 pub mod ord;
 pub mod result;
 pub mod time;
+pub mod typenum;

util/src/result.rs

@@ -1,3 +1,6 @@
+use std::convert::Infallible;
+use std::result::Result;
+
 /// Try block basically…returns a result and allows the use of the question mark operator inside
 #[macro_export]
 macro_rules! attempt {
@@ -5,3 +8,92 @@ macro_rules! attempt {
         (|| -> ::anyhow::Result<_> { $block })()
     };
 }
+
+/// Trait for container types that guarantee successful unwrapping.
+///
+/// The `.guaranteed()` function can be used over unwrap to show that
+/// the function will not panic.
+///
+/// Implementations must not panic.
+pub trait GuaranteedValue {
+    type Value;
+
+    /// Extract the contained value while being panic-safe, like .unwrap()
+    ///
+    /// # Panic Safety
+    ///
+    /// Implementations of guaranteed() must not panic.
+    fn guaranteed(self) -> Self::Value;
+}
+
+/// A result type that never contains an error.
+///
+/// This is mostly useful in generic contexts.
+///
+/// # Examples
+///
+/// ```
+/// use std::num::Wrapping;
+/// use std::result::Result;
+/// use std::convert::Infallible;
+/// use std::ops::Add;
+///
+/// use rosenpass_util::result::{Guaranteed, GuaranteedValue};
+///
+/// trait FailableAddition: Sized {
+///   type Error;
+///   fn failable_addition(&self, other: &Self) -> Result<Self, Self::Error>;
+/// }
+///
+/// #[derive(Copy, Clone, Debug, Eq, PartialEq)]
+/// struct OverflowError;
+///
+/// impl<T> FailableAddition for Wrapping<T>
+///   where for <'a> &'a Wrapping<T>: Add<Output = Wrapping<T>> {
+///   type Error = Infallible;
+///   fn failable_addition(&self, other: &Self) -> Guaranteed<Self> {
+///     Ok(self + other)
+///   }
+/// }
+///
+/// impl FailableAddition for u32 {
+///   type Error = OverflowError;
+///   fn failable_addition(&self, other: &Self) -> Result<Self, Self::Error> {
+///     match self.checked_add(*other) {
+///         Some(v) => Ok(v),
+///         None => Err(OverflowError),
+///     }
+///   }
+/// }
+///
+/// fn failable_multiply<T>(a: &T, b: u32)
+///         -> Result<T, T::Error>
+///     where
+///         T: FailableAddition {
+///     assert!(b >= 2); // Acceptable only because this is for demonstration purposes
+///     let mut accu = a.failable_addition(a)?;
+///     for _ in 2..b {
+///         accu = accu.failable_addition(a)?;
+///     }
+///     Ok(accu)
+/// }
+///
+/// // We can use .guaranteed() with Wrapping<u32>, since the operation uses
+/// // the Infallible error type.
+/// // We can also use unwrap which just happens to not raise an error.
+/// assert_eq!(failable_multiply(&Wrapping(42u32), 3).guaranteed(), Wrapping(126));
+/// assert_eq!(failable_multiply(&Wrapping(42u32), 3).unwrap(), Wrapping(126));
+///
+/// // We can not use .guaranteed() with u32, since there can be an error.
+/// // We can however use unwrap(), which may panic
+/// //assert_eq!(failable_multiply(&42u32, 3).guaranteed(), 126); // COMPILER ERROR
+/// assert_eq!(failable_multiply(&42u32, 3).unwrap(), 126);
+/// ```
+pub type Guaranteed<T> = Result<T, Infallible>;
+
+impl<T> GuaranteedValue for Guaranteed<T> {
+    type Value = T;
+    fn guaranteed(self) -> Self::Value {
+        self.unwrap()
+    }
+}

util/src/typenum.rs

@@ -0,0 +1,341 @@
+use typenum::bit::{B0, B1};
+use typenum::int::{NInt, PInt, Z0};
+use typenum::marker_traits as markers;
+use typenum::uint::{UInt, UTerm};
+
+/// Convenience macro to convert type numbers to constant integers
+#[macro_export]
+macro_rules! typenum2const {
+    ($val:ty) => {
+        typenum2const!($val as _)
+    };
+    ($val:ty as $type:ty) => {
+        <$val as $crate::typenum::IntoConst<$type>>::VALUE
+    };
+}
+
+/// Trait implemented by constant integers to facilitate conversion to constant integers
+pub trait IntoConst<T> {
+    const VALUE: T;
+}
+
+struct ConstApplyNegSign<T: AssociatedUnsigned, Param: IntoConst<<T as AssociatedUnsigned>::Type>>(
+    *const T,
+    *const Param,
+);
+struct ConstApplyPosSign<T: AssociatedUnsigned, Param: IntoConst<<T as AssociatedUnsigned>::Type>>(
+    *const T,
+    *const Param,
+);
+struct ConstLshift<T, Param: IntoConst<T>, const SHIFT: i32>(*const T, *const Param); // impl IntoConst<T>
+struct ConstAdd<T, Lhs: IntoConst<T>, Rhs: IntoConst<T>>(*const T, *const Lhs, *const Rhs); // impl IntoConst<T>
+
+/// Assigns an unsigned type to a signed type
+trait AssociatedUnsigned {
+    type Type;
+}
+
+macro_rules! impl_into_const {
+    ( $from:ty as $to:ty := $impl:expr) => {
+        impl IntoConst<$to> for $from {
+            const VALUE: $to = $impl;
+        }
+    };
+}
+
+macro_rules! impl_numeric_into_const_common {
+    ($type:ty) => {
+        impl_into_const! { Z0 as $type := 0 }
+        impl_into_const! { B0 as $type := 0 }
+        impl_into_const! { B1 as $type := 1 }
+        impl_into_const! { UTerm as $type := 0 }
+
+        impl<Param: IntoConst<$type>, const SHIFT: i32> IntoConst<$type>
+            for ConstLshift<$type, Param, SHIFT>
+        {
+            const VALUE: $type = Param::VALUE << SHIFT;
+        }
+
+        impl<Lhs: IntoConst<$type>, Rhs: IntoConst<$type>> IntoConst<$type>
+            for ConstAdd<$type, Lhs, Rhs>
+        {
+            const VALUE: $type =
+                <Lhs as IntoConst<$type>>::VALUE + <Rhs as IntoConst<$type>>::VALUE;
+        }
+    };
+}
+
+macro_rules! impl_numeric_into_const_unsigned {
+    ($($to_list:ty),*) =>  {
+        $( impl_numeric_into_const_unsigned! { @impl $to_list } )*
+    };
+
+    (@impl $type:ty) =>  {
+        impl_numeric_into_const_common!{ $type }
+
+        impl AssociatedUnsigned for $type {
+            type Type = $type;
+        }
+
+        impl<Param: IntoConst<$type>> IntoConst<$type> for ConstApplyPosSign<$type, Param> {
+            const VALUE : $type = Param::VALUE;
+        }
+    };
+}
+
+macro_rules! impl_numeric_into_const_signed {
+    ($($to_list:ty : $unsigned_list:ty),*) =>  {
+        $( impl_numeric_into_const_signed! { @impl $to_list : $unsigned_list} )*
+    };
+
+    (@impl $type:ty : $unsigned:ty) =>  {
+        impl_numeric_into_const_common!{ $type }
+
+        impl AssociatedUnsigned for $type {
+            type Type = $unsigned;
+        }
+
+        impl<Param: IntoConst<$unsigned>> IntoConst<$type> for ConstApplyPosSign<$type, Param> {
+            const VALUE : $type = Param::VALUE as $type;
+        }
+
+        impl<Param: IntoConst<$unsigned>> IntoConst<$type> for ConstApplyNegSign<$type, Param> {
+            const VALUE : $type =
+                if Param::VALUE == (1 as $unsigned).rotate_right(1) {
+                    // Handle the negative value without an associated positive value (e.g. -128
+                    // for i8)
+                    < $type >::MIN
+                } else {
+                    -(Param::VALUE as $type)
+                };
+        }
+    };
+}
+
+impl_into_const! { B0 as bool := false }
+impl_into_const! { B1 as bool := true }
+impl_numeric_into_const_unsigned! { usize, u8, u16, u32, u64, u128 }
+impl_numeric_into_const_signed! { isize : usize, i8 : u8, i16 : u16, i32 : u32, i64 : u64, i128 : u128 }
+
+// Unsigned type numbers to const integers
+impl<Ret, Rest, Bit> IntoConst<Ret> for UInt<Rest, Bit>
+where
+    Rest: IntoConst<Ret>,
+    Bit: IntoConst<Ret>,
+    ConstLshift<Ret, Rest, 1>: IntoConst<Ret>,
+    ConstAdd<Ret, ConstLshift<Ret, Rest, 1>, Bit>: IntoConst<Ret>,
+{
+    const VALUE: Ret = <ConstAdd<Ret, ConstLshift<Ret, Rest, 1>, Bit> as IntoConst<Ret>>::VALUE;
+}
+
+// Signed type numbers with positive sign to const integers
+impl<Ret, Unsigned> IntoConst<Ret> for PInt<Unsigned>
+where
+    Ret: AssociatedUnsigned,
+    Unsigned: markers::Unsigned + markers::NonZero + IntoConst<<Ret as AssociatedUnsigned>::Type>,
+    ConstApplyPosSign<Ret, Unsigned>: IntoConst<Ret>,
+{
+    const VALUE: Ret = <ConstApplyPosSign<Ret, Unsigned> as IntoConst<Ret>>::VALUE;
+}
+
+// Signed type numbers with negative sign to const integers
+impl<Ret, Unsigned> IntoConst<Ret> for NInt<Unsigned>
+where
+    Ret: AssociatedUnsigned,
+    Unsigned: markers::Unsigned + markers::NonZero + IntoConst<<Ret as AssociatedUnsigned>::Type>,
+    ConstApplyNegSign<Ret, Unsigned>: IntoConst<Ret>,
+{
+    const VALUE: Ret = <ConstApplyNegSign<Ret, Unsigned> as IntoConst<Ret>>::VALUE;
+}
+
+mod test {
+    use static_assertions::const_assert_eq;
+    use typenum::consts::*;
+    use typenum::op;
+
+    macro_rules! test_const_conversion {
+        // Type groups
+
+        (($($typenum:ty),*) >= u7 = $const:expr $(; $($rest:tt)*)?) => {
+            $( test_const_conversion! { ($typenum) as (u8, u16, u32, u64, u128) = $const } )*
+            $( test_const_conversion! { ($typenum) as (i8, i16, i32, i64, i128) = $const } )*
+            $( test_const_conversion! { $($rest)* } )?
+        };
+
+        (($($typenum:ty),*) >= u8 = $const:expr $(; $($rest:tt)*)?) => {
+            $( test_const_conversion! { ($typenum) as (u8, u16, u32, u64, u128) = $const } )*
+            $( test_const_conversion! { ($typenum) as (    i16, i32, i64, i128) = $const } )*
+            $( test_const_conversion! { $($rest)* } )?
+        };
+
+        (($($typenum:ty),*) >= u15 = $const:expr $(; $($rest:tt)*)?) => {
+            $( test_const_conversion! { ($typenum) as (    u16, u32, u64, u128) = $const } )*
+            $( test_const_conversion! { ($typenum) as (    i16, i32, i64, i128) = $const } )*
+            $( test_const_conversion! { $($rest)* } )?
+        };
+
+        (($($typenum:ty),*) >= u16 = $const:expr $(; $($rest:tt)*)?) => {
+            $( test_const_conversion! { ($typenum) as (    u16, u32, u64, u128) = $const } )*
+            $( test_const_conversion! { ($typenum) as (         i32, i64, i128) = $const } )*
+            $( test_const_conversion! { $($rest)* } )?
+        };
+
+        (($($typenum:ty),*) >= u31 = $const:expr $(; $($rest:tt)*)?) => {
+            $( test_const_conversion! { ($typenum) as (         u32, u64, u128) = $const } )*
+            $( test_const_conversion! { ($typenum) as (         i32, i64, i128) = $const } )*
+            $( test_const_conversion! { $($rest)* } )?
+        };
+
+        (($($typenum:ty),*) >= u32 = $const:expr $(; $($rest:tt)*)?) => {
+            $( test_const_conversion! { ($typenum) as (         u32, u64, u128) = $const } )*
+            $( test_const_conversion! { ($typenum) as (              i64, i128) = $const } )*
+            $( test_const_conversion! { $($rest)* } )?
+        };
+
+        (($($typenum:ty),*) >= u63 = $const:expr $(; $($rest:tt)*)?) => {
+            $( test_const_conversion! { ($typenum) as (              u64, u128) = $const } )*
+            $( test_const_conversion! { ($typenum) as (              i64, i128) = $const } )*
+            $( test_const_conversion! { $($rest)* } )?
+        };
+
+        (($($typenum:ty),*) >= u64 = $const:expr $(; $($rest:tt)*)?) => {
+            $( test_const_conversion! { ($typenum) as (              u64, u128) = $const } )*
+            $( test_const_conversion! { ($typenum) as (                   i128) = $const } )*
+            $( test_const_conversion! { $($rest)* } )?
+        };
+
+        (($($typenum:ty),*) >= u127 = $const:expr $(; $($rest:tt)*)?) => {
+            $( test_const_conversion! { ($typenum) as (                   u128) = $const } )*
+            $( test_const_conversion! { ($typenum) as (                   i128) = $const } )*
+            $( test_const_conversion! { $($rest)* } )?
+        };
+
+        (($($typenum:ty),*) >= u128 = $const:expr $(; $($rest:tt)*)?) => {
+            $( test_const_conversion! { ($typenum) as (                   u128) = $const } )*
+            $( test_const_conversion! { ($typenum) as (                       ) = $const } )*
+            $( test_const_conversion! { $($rest)* } )?
+        };
+
+        (($($typenum:ty),*) >= i8 = $const:expr $(; $($rest:tt)*)?) => {
+            $( test_const_conversion! { ($typenum) as (i8, i16, i32, i64, i128) = $const } )*
+            $( test_const_conversion! { $($rest)* } )?
+        };
+
+        (($($typenum:ty),*) >= i16 = $const:expr $(; $($rest:tt)*)?) => {
+            $( test_const_conversion! { ($typenum) as (    i16, i32, i64, i128) = $const } )*
+            $( test_const_conversion! { $($rest)* } )?
+        };
+
+        (($($typenum:ty),*) >= i32 = $const:expr $(; $($rest:tt)*)?) => {
+            $( test_const_conversion! { ($typenum) as (         i32, i64, i128) = $const } )*
+            $( test_const_conversion! { $($rest)* } )?
+        };
+
+        (($($typenum:ty),*) >= i64 = $const:expr $(; $($rest:tt)*)?) => {
+            $( test_const_conversion! { ($typenum) as (              i64, i128) = $const } )*
+            $( test_const_conversion! { $($rest)* } )?
+        };
+
+        (($($typenum:ty),*) >= i128 = $const:expr $(; $($rest:tt)*)?) => {
+            $( test_const_conversion! { ($typenum) as (                   i128) = $const } )*
+            $( test_const_conversion! { $($rest)* } )?
+        };
+
+        // Basic operation
+
+        () => {};
+
+        (($($typenum:ty),*) as () = $const:expr $(; $($rest:tt)*)?) => {
+            $( test_const_conversion! { $($rest)* } )?
+        };
+
+        (($($typenum:ty),*) as ($type:ty) = $const:expr $(; $($rest:tt)*)?) => {
+            $( test_const_conversion! { @impl ($typenum) as ($type) = $const } )*
+            $( test_const_conversion! { $($rest)* } )?
+        };
+
+        (($($typenum:ty),*) as ($type_head:ty, $($type_tail:ty),*) = $const:expr $(; $($rest:tt)*)?) => {
+            $( test_const_conversion! { @impl ($typenum) as ($type_head) = $const } )*
+            test_const_conversion! { ($($typenum),*) as ($($type_tail),*) = $const }
+            $( test_const_conversion! { $($rest)* } )?
+        };
+
+        (@impl ($typenum:ty) as ($type:ty) = $const:expr $(; $($rest:tt)*)?) => {
+            const_assert_eq!(typenum2const!($typenum as $type), $const);
+            $( test_const_conversion!($($rest)*); )?
+        };
+    }
+
+    test_const_conversion! {
+        (B0, False) as (bool, bool) = false;
+
+        (B0, U0, Z0) >= u7 = 0;
+        (B1, U1, P1) >= u7 = 1;
+
+        (U2, P2) >= u7 = 2;
+        (B1, True) as (bool) = true;
+        (U3, P3) >= u7 = 3;
+        (U8, P8) >= u7 = 8;
+        (U127, P127) >= u7 = 127;
+        (U220, P220) >= u8 = 220;
+        (U255, P255) >= u8 = 255;
+        (U1000, P1000) >= u15 = 1000;
+        (U10000, P10000) >= u15 = 10000;
+        (U16384, P16384) >= u15 = 16384;
+        (U32768, P32768) >= u16 = 32768;
+        (U65536, P65536) >= u31 = 65536;
+        (U100000, P100000) >= u31 = 100000;
+        (U1000000000, P1000000000) >= u31 = 1000000000;
+        (U2147483648, P2147483648) >= u32 = 2147483648;
+        (U1000000000000000000, P1000000000000000000) >= u63 = 1000000000000000000;
+        (U1000000000000000000, P1000000000000000000) >= u63 = 1000000000000000000;
+
+        (U9223372036854775808) >= u64 = 9223372036854775808;
+        (U10000000000000000000) >= u64 = 10000000000000000000;
+
+        (N10000) >= i16 = -10000;
+        (N1000000) >= i32 = -1000000;
+        (N1000000000) >= i32 = -1000000000;
+        (N1000000000000) >= i64 = -1000000000000;
+    }
+
+    const_assert_eq!(127, (!(1u8.rotate_right(1)) - 0) as _);
+    const_assert_eq!(126, (!(1u8.rotate_right(1)) - 1) as _);
+    const_assert_eq!(255, (!(0u8.rotate_right(1)) - 0) as _);
+    const_assert_eq!(254, (!(0u8.rotate_right(1)) - 1) as _);
+
+    test_const_conversion! {
+        (op!(pow(U2, U7) - U1))   >= u7   = (!(1u8.rotate_right(1)) - 0) as _;
+        (op!(pow(U2, U7) - U2))   >= u7   = (!(1u8.rotate_right(1)) - 1) as _;
+        (op!(pow(U2, U15) - U1))  >= u15  = (!(1u16.rotate_right(1)) - 0) as _;
+        (op!(pow(U2, U15) - U2))  >= u15  = (!(1u16.rotate_right(1)) - 1) as _;
+        (op!(pow(U2, U31) - U1))  >= u31  = (!(1u32.rotate_right(1)) - 0) as _;
+        (op!(pow(U2, U31) - U2))  >= u31  = (!(1u32.rotate_right(1)) - 1) as _;
+        (op!(pow(U2, U63) - U1))  >= u63  = (!(1u64.rotate_right(1)) - 0) as _;
+        (op!(pow(U2, U63) - U2))  >= u63  = (!(1u64.rotate_right(1)) - 1) as _;
+        (op!(pow(U2, U127) - U1)) >= u127 = (!(1u128.rotate_right(1)) - 0) as _;
+        (op!(pow(U2, U127) - U2)) >= u127 = (!(1u128.rotate_right(1)) - 1) as _;
+
+        (op!(pow(U2, U8) - U1))   >= u8   = (u8::MAX - 0) as _;
+        (op!(pow(U2, U8) - U2))   >= u8   = (u8::MAX - 1) as _;
+        (op!(pow(U2, U16) - U1))  >= u16  = (u16::MAX - 0) as _;
+        (op!(pow(U2, U16) - U2))  >= u16  = (u16::MAX - 1) as _;
+        (op!(pow(U2, U32) - U1))  >= u32  = (u32::MAX - 0) as _;
+        (op!(pow(U2, U32) - U2))  >= u32  = (u32::MAX - 1) as _;
+        (op!(pow(U2, U64) - U1))  >= u64  = (u64::MAX - 0) as _;
+        (op!(pow(U2, U64) - U2))  >= u64  = (u64::MAX - 1) as _;
+        (op!(pow(U2, U128) - U1)) >= u128 = (u128::MAX - 0) as _;
+        (op!(pow(U2, U128) - U2)) >= u128 = (u128::MAX - 1) as _;
+
+        (op!(Z0 - pow(P2, P7) + Z0)) >= i8 = (i8::MIN + 0) as _;
+        (op!(Z0 - pow(P2, P7) + P1)) >= i8 = (i8::MIN + 1) as _;
+        (op!(Z0 - pow(P2, P15) + Z0)) >= i16 = (i16::MIN + 0) as _;
+        (op!(Z0 - pow(P2, P15) + P1)) >= i16 = (i16::MIN + 1) as _;
+        (op!(Z0 - pow(P2, P31) + Z0)) >= i32 = (i32::MIN + 0) as _;
+        (op!(Z0 - pow(P2, P31) + P1)) >= i32 = (i32::MIN + 1) as _;
+        (op!(Z0 - pow(P2, P63) + Z0)) >= i64 = (i64::MIN + 0) as _;
+        (op!(Z0 - pow(P2, P63) + P1)) >= i64 = (i64::MIN + 1) as _;
+        (op!(Z0 - pow(P2, P127) + Z0)) >= i128 = (i128::MIN + 0) as _;
+        (op!(Z0 - pow(P2, P127) + P1)) >= i128 = (i128::MIN + 1) as _;
+    }
+}

wireguard-broker/Cargo.toml

@@ -0,0 +1,41 @@
+[package]
+name = "rosenpass-wireguard-broker"
+authors = ["Karolin Varner <karo@cupdev.net>", "wucke13 <wucke13@gmail.com>"]
+version = "0.1.0"
+edition = "2021"
+license = "MIT OR Apache-2.0"
+description = "Rosenpass internal broker that runs as root and supplies exchanged keys to the kernel."
+homepage = "https://rosenpass.eu/"
+repository = "https://github.com/rosenpass/rosenpass"
+readme = "readme.md"
+
+[dependencies]
+thiserror = { workspace = true }
+rosenpass-lenses = { workspace = true }
+paste = { workspace = true } # TODO: Using lenses should not necessitate importing paste
+
+# Privileged only
+wireguard-uapi = { workspace = true }
+
+# Socket handler only
+rosenpass-to = { workspace = true }
+anyhow = { workspace = true }
+clap = { workspace = true }
+env_logger = { workspace = true }
+log = { workspace = true }
+
+# Mio broker client
+mio = { workspace = true }
+rosenpass-util = { workspace = true }
+
+[[bin]]
+name = "rosenpass-wireguard-broker-privileged"
+path = "src/bin/priviledged.rs"
+test = false
+doc = false
+
+[[bin]]
+name = "rosenpass-wireguard-broker-socket-handler"
+test = false
+path = "src/bin/socket_handler.rs"
+doc = false

wireguard-broker/readme.md

@@ -0,0 +1,5 @@
+# Rosenpass internal broker supplying WireGuard with keys.
+
+This crate contains a small application purpose-built to supply WireGuard in the linux kernel with pre-shared keys.
+
+This is an internal library; not guarantee is made about its API at this point in time.

wireguard-broker/src/api/client.rs

@@ -0,0 +1,152 @@
+use std::{borrow::BorrowMut, marker::PhantomData};
+
+use rosenpass_lenses::LenseView;
+
+use crate::{
+    api::msgs::{self, EnvelopeExt, SetPskRequestExt, SetPskResponseExt},
+    WireGuardBroker,
+};
+
+#[derive(thiserror::Error, Debug, Clone, Eq, PartialEq)]
+pub enum BrokerClientPollResponseError<RecvError> {
+    #[error(transparent)]
+    IoError(RecvError),
+    #[error("Invalid message.")]
+    InvalidMessage,
+}
+
+impl<RecvError> From<msgs::InvalidMessageTypeError> for BrokerClientPollResponseError<RecvError> {
+    fn from(value: msgs::InvalidMessageTypeError) -> Self {
+        let msgs::InvalidMessageTypeError = value; // Assert that this is a unit type
+        BrokerClientPollResponseError::<RecvError>::InvalidMessage
+    }
+}
+
+fn io_pollerr<RecvError>(e: RecvError) -> BrokerClientPollResponseError<RecvError> {
+    BrokerClientPollResponseError::<RecvError>::IoError(e)
+}
+
+fn invalid_msg_pollerr<RecvError>() -> BrokerClientPollResponseError<RecvError> {
+    BrokerClientPollResponseError::<RecvError>::InvalidMessage
+}
+
+#[derive(thiserror::Error, Debug, Clone, Eq, PartialEq)]
+pub enum BrokerClientSetPskError<SendError> {
+    #[error(transparent)]
+    IoError(SendError),
+    #[error("Interface name out of bounds")]
+    IfaceOutOfBounds,
+}
+
+pub trait BrokerClientIo {
+    type SendError;
+    type RecvError;
+
+    fn send_msg(&mut self, buf: &[u8]) -> Result<(), Self::SendError>;
+    fn recv_msg(&mut self) -> Result<Option<&[u8]>, Self::RecvError>;
+}
+
+#[derive(Debug)]
+pub struct BrokerClient<'a, Io, IoRef>
+where
+    Io: BrokerClientIo,
+    IoRef: 'a + BorrowMut<Io>,
+{
+    io: IoRef,
+    _phantom_io: PhantomData<&'a mut Io>,
+}
+
+impl<'a, Io, IoRef> BrokerClient<'a, Io, IoRef>
+where
+    Io: BrokerClientIo,
+    IoRef: 'a + BorrowMut<Io>,
+{
+    pub fn new(io: IoRef) -> Self {
+        Self {
+            io,
+            _phantom_io: PhantomData,
+        }
+    }
+
+    pub fn io(&self) -> &IoRef {
+        &self.io
+    }
+
+    pub fn io_mut(&mut self) -> &mut IoRef {
+        &mut self.io
+    }
+
+    pub fn poll_response(
+        &mut self,
+    ) -> Result<Option<msgs::SetPskResult>, BrokerClientPollResponseError<Io::RecvError>> {
+        let res: &[u8] = match self.io.borrow_mut().recv_msg().map_err(io_pollerr)? {
+            Some(r) => r,
+            None => return Ok(None),
+        };
+
+        let typ = res.get(0).ok_or(invalid_msg_pollerr())?;
+        let typ = msgs::MsgType::try_from(*typ)?;
+        let msgs::MsgType::SetPsk = typ; // Assert type
+
+        let res: msgs::Envelope<_, msgs::SetPskResponse<&[u8]>> = res
+            .envelope_truncating()
+            .map_err(|_| invalid_msg_pollerr())?;
+        let res: msgs::SetPskResponse<&[u8]> = res
+            .payload()
+            .set_psk_response()
+            .map_err(|_| invalid_msg_pollerr())?;
+        let res: msgs::SetPskResponseReturnCode = res.return_code()[0]
+            .try_into()
+            .map_err(|_| invalid_msg_pollerr())?;
+        let res: msgs::SetPskResult = res.into();
+
+        Ok(Some(res))
+    }
+}
+
+impl<'a, Io, IoRef> WireGuardBroker for BrokerClient<'a, Io, IoRef>
+where
+    Io: BrokerClientIo,
+    IoRef: 'a + BorrowMut<Io>,
+{
+    type Error = BrokerClientSetPskError<Io::SendError>;
+
+    fn set_psk(
+        &mut self,
+        iface: &str,
+        peer_id: [u8; 32],
+        psk: [u8; 32],
+    ) -> Result<(), Self::Error> {
+        use BrokerClientSetPskError::*;
+        const BUF_SIZE: usize = <msgs::Envelope<(), msgs::SetPskRequest<()>> as LenseView>::LEN;
+
+        // Allocate message
+        let mut req = [0u8; BUF_SIZE];
+
+        // Construct message view
+        let mut req: msgs::Envelope<_, msgs::SetPskRequest<&mut [u8]>> =
+            (&mut req as &mut [u8]).envelope_truncating().unwrap();
+
+        // Populate envelope
+        req.msg_type_mut()
+            .copy_from_slice(&[msgs::MsgType::SetPsk as u8]);
+        {
+            // Derived payload
+            let mut req: msgs::SetPskRequest<&mut [u8]> =
+                req.payload_mut().set_psk_request().unwrap();
+
+            // Populate payload
+            req.peer_id_mut().copy_from_slice(&peer_id);
+            req.psk_mut().copy_from_slice(&psk);
+            req.set_iface(iface).ok_or(IfaceOutOfBounds)?;
+        }
+
+        // Send message
+        self.io
+            .borrow_mut()
+            .send_msg(req.all_bytes())
+            .map_err(IoError)?;
+
+        Ok(())
+    }
+}

wireguard-broker/src/api/mio_client.rs

@@ -0,0 +1,204 @@
+use std::collections::VecDeque;
+use std::io::{ErrorKind, Read, Write};
+
+use anyhow::{bail, ensure};
+
+use crate::WireGuardBroker;
+
+use super::client::{
+    BrokerClient, BrokerClientIo, BrokerClientPollResponseError, BrokerClientSetPskError,
+};
+use super::msgs;
+
+#[derive(Debug)]
+pub struct MioBrokerClient {
+    inner: BrokerClient<'static, MioBrokerClientIo, MioBrokerClientIo>,
+}
+
+#[derive(Debug)]
+struct MioBrokerClientIo {
+    socket: mio::net::TcpStream,
+    send_buf: VecDeque<u8>,
+    receiving_size: bool,
+    recv_buf: Vec<u8>,
+    recv_off: usize,
+}
+
+impl MioBrokerClient {
+    pub fn new(socket: mio::net::TcpStream) -> Self {
+        let io = MioBrokerClientIo {
+            socket,
+            send_buf: VecDeque::new(),
+            receiving_size: false,
+            recv_buf: Vec::new(),
+            recv_off: 0,
+        };
+        let inner = BrokerClient::new(io);
+        Self { inner }
+    }
+
+    pub fn poll(&mut self) -> anyhow::Result<Option<msgs::SetPskResult>> {
+        self.inner.io_mut().flush()?;
+
+        // This sucks
+        match self.inner.poll_response() {
+            Ok(res) => {
+                return Ok(res);
+            }
+            Err(BrokerClientPollResponseError::IoError(e)) => {
+                return Err(e);
+            }
+            Err(BrokerClientPollResponseError::InvalidMessage) => {
+                bail!("Invalid message");
+            }
+        };
+    }
+}
+
+impl WireGuardBroker for MioBrokerClient {
+    type Error = anyhow::Error;
+
+    fn set_psk(&mut self, iface: &str, peer_id: [u8; 32], psk: [u8; 32]) -> anyhow::Result<()> {
+        use BrokerClientSetPskError::*;
+        let e = self.inner.set_psk(iface, peer_id, psk);
+        match e {
+            Ok(()) => Ok(()),
+            Err(IoError(e)) => Err(e),
+            Err(IfaceOutOfBounds) => bail!("Interface name size is out of bounds."),
+        }
+    }
+}
+
+impl BrokerClientIo for MioBrokerClientIo {
+    type SendError = anyhow::Error;
+    type RecvError = anyhow::Error;
+
+    fn send_msg(&mut self, buf: &[u8]) -> Result<(), Self::SendError> {
+        self.flush()?;
+        self.send_or_buffer(&(buf.len() as u64).to_le_bytes())?;
+        self.send_or_buffer(&buf)?;
+        self.flush()?;
+
+        Ok(())
+    }
+
+    fn recv_msg(&mut self) -> Result<Option<&[u8]>, Self::RecvError> {
+        // Stale message in receive buffer. Reset!
+        if self.recv_off == self.recv_buf.len() {
+            self.receiving_size = true;
+            self.recv_off = 0;
+            self.recv_buf.resize(8, 0);
+        }
+
+        // Try filling the receive buffer
+        self.recv_off += raw_recv(&self.socket, &mut self.recv_buf[self.recv_off..])?;
+        if self.recv_off < self.recv_buf.len() {
+            return Ok(None);
+        }
+
+        // Received size, now start receiving
+        if self.receiving_size {
+            // Received the size
+            // Parse the received length
+            let len: &[u8; 8] = self.recv_buf[..].try_into().unwrap();
+            let len: usize = u64::from_le_bytes(*len) as usize;
+
+            ensure!(
+                len <= msgs::RESPONSE_MSG_BUFFER_SIZE,
+                "Oversized buffer ({len}) in psk buffer response."
+            );
+
+            // Prepare the message buffer for receiving an actual message of the given size
+            self.receiving_size = false;
+            self.recv_off = 0;
+            self.recv_buf.resize(len, 0);
+
+            // Try to receive the message
+            return self.recv_msg();
+        }
+
+        // Received an actual message
+        return Ok(Some(&self.recv_buf[..]));
+    }
+}
+
+impl MioBrokerClientIo {
+    fn flush(&mut self) -> anyhow::Result<()> {
+        let (fst, snd) = self.send_buf.as_slices();
+
+        let (written, res) = match raw_send(&self.socket, fst) {
+            Ok(w1) if w1 >= fst.len() => match raw_send(&self.socket, snd) {
+                Ok(w2) => (w1 + w2, Ok(())),
+                Err(e) => (w1, Err(e)),
+            },
+            Ok(w1) => (w1, Ok(())),
+            Err(e) => (0, Err(e)),
+        };
+
+        self.send_buf.drain(..written);
+
+        (&self.socket).try_io(|| (&self.socket).flush())?;
+
+        res
+    }
+
+    fn send_or_buffer(&mut self, buf: &[u8]) -> anyhow::Result<()> {
+        let mut off = 0;
+
+        if self.send_buf.is_empty() {
+            off += raw_send(&self.socket, buf)?;
+        }
+
+        self.send_buf.extend((&buf[off..]).iter());
+
+        Ok(())
+    }
+}
+
+fn raw_send(mut socket: &mio::net::TcpStream, data: &[u8]) -> anyhow::Result<usize> {
+    let mut off = 0;
+
+    socket.try_io(|| {
+        loop {
+            if off == data.len() {
+                return Ok(());
+            }
+            match socket.write(&data[off..]) {
+                Ok(n) => {
+                    off += n;
+                }
+                Err(e) if e.kind() == ErrorKind::Interrupted => {
+                    // pass – retry
+                }
+                Err(e) if off > 0 || e.kind() == ErrorKind::WouldBlock => return Ok(()),
+                Err(e) => return Err(e),
+            }
+        }
+    })?;
+
+    return Ok(off);
+}
+
+fn raw_recv(mut socket: &mio::net::TcpStream, out: &mut [u8]) -> anyhow::Result<usize> {
+    let mut off = 0;
+
+    socket.try_io(|| {
+        loop {
+            if off == out.len() {
+                return Ok(());
+            }
+            match socket.read(&mut out[off..]) {
+                Ok(n) => {
+                    off += n;
+                }
+                Err(e) if e.kind() == ErrorKind::Interrupted => {
+                    // pass – retry
+                }
+                Err(e) if off > 0 || e.kind() == ErrorKind::WouldBlock => return Ok(()),
+                Err(e) => return Err(e),
+            }
+        }
+    })?;
+
+    return Ok(off);
+}

wireguard-broker/src/api/mod.rs

@@ -0,0 +1,4 @@
+pub mod client;
+pub mod mio_client;
+pub mod msgs;
+pub mod server;

wireguard-broker/src/api/msgs.rs

@@ -0,0 +1,140 @@
+use std::result::Result;
+use std::str::{from_utf8, Utf8Error};
+
+use rosenpass_lenses::{lense, LenseView};
+
+pub const REQUEST_MSG_BUFFER_SIZE: usize = <Envelope<(), SetPskRequest<()>> as LenseView>::LEN;
+pub const RESPONSE_MSG_BUFFER_SIZE: usize = <Envelope<(), SetPskResponse<()>> as LenseView>::LEN;
+
+lense! { Envelope<M> :=
+    /// [MsgType] of this message
+    msg_type: 1,
+    /// Reserved for future use
+    reserved: 3,
+    /// The actual Paylod
+    payload: M::LEN
+}
+
+lense! { SetPskRequest :=
+    peer_id: 32,
+    psk: 32,
+    iface_size: 1, // TODO: We should have variable length strings in lenses
+    iface_buf: 255
+}
+
+impl SetPskRequest<&[u8]> {
+    pub fn iface_bin(&self) -> &[u8] {
+        let len = self.iface_size()[0] as usize;
+        &self.iface_buf()[..len]
+    }
+
+    pub fn iface(&self) -> Result<&str, Utf8Error> {
+        from_utf8(self.iface_bin())
+    }
+}
+
+impl SetPskRequest<&mut [u8]> {
+    pub fn set_iface_bin(&mut self, iface: &[u8]) -> Option<()> {
+        (iface.len() < 256).then_some(())?; // Assert iface.len() < 256
+
+        self.iface_size_mut()[0] = iface.len() as u8;
+
+        self.iface_buf_mut().fill(0);
+        (&mut self.iface_buf_mut()[..iface.len()]).copy_from_slice(iface);
+
+        Some(())
+    }
+
+    pub fn set_iface(&mut self, iface: &str) -> Option<()> {
+        self.set_iface_bin(iface.as_bytes())
+    }
+}
+
+lense! { SetPskResponse :=
+    return_code: 1
+}
+
+#[derive(thiserror::Error, Debug, Clone, Eq, PartialEq)]
+pub enum SetPskError {
+    #[error("The wireguard pre-shared-key assignment broker experienced an internal error.")]
+    InternalError,
+    #[error("The indicated wireguard interface does not exist")]
+    NoSuchInterface,
+    #[error("The indicated peer does not exist on the wireguard interface")]
+    NoSuchPeer,
+}
+
+pub type SetPskResult = Result<(), SetPskError>;
+
+#[repr(u8)]
+#[derive(Hash, PartialEq, Eq, PartialOrd, Ord, Debug, Clone, Copy)]
+pub enum SetPskResponseReturnCode {
+    Success = 0x00,
+    InternalError = 0x01,
+    NoSuchInterface = 0x02,
+    NoSuchPeer = 0x03,
+}
+
+#[derive(Eq, PartialEq, Debug, Clone)]
+pub struct InvalidSetPskResponseError;
+
+impl TryFrom<u8> for SetPskResponseReturnCode {
+    type Error = InvalidSetPskResponseError;
+
+    fn try_from(value: u8) -> Result<Self, Self::Error> {
+        use SetPskResponseReturnCode::*;
+        match value {
+            0x00 => Ok(Success),
+            0x01 => Ok(InternalError),
+            0x02 => Ok(NoSuchInterface),
+            0x03 => Ok(NoSuchPeer),
+            _ => Err(InvalidSetPskResponseError),
+        }
+    }
+}
+
+impl From<SetPskResponseReturnCode> for SetPskResult {
+    fn from(value: SetPskResponseReturnCode) -> Self {
+        use SetPskError as E;
+        use SetPskResponseReturnCode as C;
+        match value {
+            C::Success => Ok(()),
+            C::InternalError => Err(E::InternalError),
+            C::NoSuchInterface => Err(E::NoSuchInterface),
+            C::NoSuchPeer => Err(E::NoSuchPeer),
+        }
+    }
+}
+
+impl From<SetPskResult> for SetPskResponseReturnCode {
+    fn from(value: SetPskResult) -> Self {
+        use SetPskError as E;
+        use SetPskResponseReturnCode as C;
+        match value {
+            Ok(()) => C::Success,
+            Err(E::InternalError) => C::InternalError,
+            Err(E::NoSuchInterface) => C::NoSuchInterface,
+            Err(E::NoSuchPeer) => C::NoSuchPeer,
+        }
+    }
+}
+
+#[repr(u8)]
+#[derive(Hash, PartialEq, Eq, PartialOrd, Ord, Debug, Clone, Copy)]
+pub enum MsgType {
+    SetPsk = 0x01,
+}
+
+#[derive(Eq, PartialEq, Debug, Clone)]
+pub struct InvalidMessageTypeError;
+
+impl TryFrom<u8> for MsgType {
+    type Error = InvalidMessageTypeError;
+
+    fn try_from(value: u8) -> Result<Self, Self::Error> {
+        match value {
+            0x01 => Ok(MsgType::SetPsk),
+            _ => Err(InvalidMessageTypeError),
+        }
+    }
+}

wireguard-broker/src/api/server.rs

@@ -0,0 +1,99 @@
+use std::borrow::BorrowMut;
+use std::marker::PhantomData;
+use std::result::Result;
+
+use rosenpass_lenses::LenseError;
+
+use crate::api::msgs::{self, EnvelopeExt, SetPskRequestExt, SetPskResponseExt};
+use crate::WireGuardBroker;
+
+#[derive(thiserror::Error, Debug, Clone, Eq, PartialEq)]
+pub enum BrokerServerError {
+    #[error("No such request type: {}", .0)]
+    NoSuchRequestType(u8),
+    #[error("Invalid message received.")]
+    InvalidMessage,
+}
+
+impl From<LenseError> for BrokerServerError {
+    fn from(value: LenseError) -> Self {
+        use BrokerServerError as Be;
+        use LenseError as Le;
+        match value {
+            Le::BufferSizeMismatch => Be::InvalidMessage,
+        }
+    }
+}
+
+impl From<msgs::InvalidMessageTypeError> for BrokerServerError {
+    fn from(value: msgs::InvalidMessageTypeError) -> Self {
+        let msgs::InvalidMessageTypeError = value; // Assert that this is a unit type
+        BrokerServerError::InvalidMessage
+    }
+}
+
+pub struct BrokerServer<'a, Err, Inner, Ref>
+where
+    msgs::SetPskError: From<Err>,
+    Inner: WireGuardBroker<Error = Err>,
+    Ref: BorrowMut<Inner> + 'a,
+{
+    inner: Ref,
+    _phantom: PhantomData<&'a mut Inner>,
+}
+
+impl<'a, Err, Inner, Ref> BrokerServer<'a, Err, Inner, Ref>
+where
+    msgs::SetPskError: From<Err>,
+    Inner: WireGuardBroker<Error = Err>,
+    Ref: 'a + BorrowMut<Inner>,
+{
+    pub fn new(inner: Ref) -> Self {
+        Self {
+            inner,
+            _phantom: PhantomData,
+        }
+    }
+
+    pub fn handle_message(
+        &mut self,
+        req: &[u8],
+        res: &mut [u8; msgs::RESPONSE_MSG_BUFFER_SIZE],
+    ) -> Result<usize, BrokerServerError> {
+        use BrokerServerError::*;
+
+        let typ = req.get(0).ok_or(InvalidMessage)?;
+        let typ = msgs::MsgType::try_from(*typ)?;
+        let msgs::MsgType::SetPsk = typ; // Assert type
+
+        let req: msgs::Envelope<_, msgs::SetPskRequest<&[u8]>> = req.envelope_truncating()?;
+        let mut res: msgs::Envelope<_, msgs::SetPskResponse<&mut [u8]>> =
+            (res as &mut [u8]).envelope_truncating()?;
+        (&mut res).msg_type_mut()[0] = msgs::MsgType::SetPsk as u8;
+        self.handle_set_psk(
+            req.payload().set_psk_request()?,
+            res.payload_mut().set_psk_response()?,
+        )?;
+        Ok(res.all_bytes().len())
+    }
+
+    fn handle_set_psk(
+        &mut self,
+        req: msgs::SetPskRequest<&[u8]>,
+        mut res: msgs::SetPskResponse<&mut [u8]>,
+    ) -> Result<(), BrokerServerError> {
+        // Using unwrap here since lenses can not return fixed-size arrays
+        // TODO: Slices should give access to fixed size arrays
+        let r: Result<(), Err> = self.inner.borrow_mut().set_psk(
+            req.iface()
+                .map_err(|_e| BrokerServerError::InvalidMessage)?,
+            req.peer_id().try_into().unwrap(),
+            req.psk().try_into().unwrap(),
+        );
+        let r: msgs::SetPskResult = r.map_err(|e| e.into());
+        let r: msgs::SetPskResponseReturnCode = r.into();
+        res.return_code_mut()[0] = r as u8;
+
+        Ok(())
+    }
+}

wireguard-broker/src/bin/priviledged.rs

@@ -0,0 +1,56 @@
+use std::io::{stdin, stdout, Read, Write};
+use std::result::Result;
+
+use rosenpass_wireguard_broker::api::msgs;
+use rosenpass_wireguard_broker::api::server::BrokerServer;
+use rosenpass_wireguard_broker::netlink as wg;
+
+#[derive(thiserror::Error, Debug)]
+pub enum BrokerAppError {
+    #[error(transparent)]
+    IoError(#[from] std::io::Error),
+    #[error(transparent)]
+    WgConnectError(#[from] wg::ConnectError),
+    #[error(transparent)]
+    WgSetPskError(#[from] wg::SetPskError),
+    #[error("Oversized message {}; something about the request is fatally wrong", .0)]
+    OversizedMessage(u64),
+}
+
+fn main() -> Result<(), BrokerAppError> {
+    let mut broker = BrokerServer::new(wg::NetlinkWireGuardBroker::new()?);
+
+    let mut stdin = stdin().lock();
+    let mut stdout = stdout().lock();
+    loop {
+        // Read the message length
+        let mut len = [0u8; 8];
+        stdin.read_exact(&mut len)?;
+
+        // Parse the message length
+        let len = u64::from_le_bytes(len);
+        if (len as usize) > msgs::REQUEST_MSG_BUFFER_SIZE {
+            return Err(BrokerAppError::OversizedMessage(len));
+        }
+
+        // Read the message itself
+        let mut req_buf = [0u8; msgs::REQUEST_MSG_BUFFER_SIZE];
+        let req_buf = &mut req_buf[..(len as usize)];
+        stdin.read_exact(req_buf)?;
+
+        // Process the message
+        let mut res_buf = [0u8; msgs::RESPONSE_MSG_BUFFER_SIZE];
+        let res = match broker.handle_message(req_buf, &mut res_buf) {
+            Ok(len) => &res_buf[..len],
+            Err(e) => {
+                eprintln!("Error processing message for wireguard PSK broker: {e:?}");
+                continue;
+            }
+        };
+
+        // Write the response
+        stdout.write_all(&(res.len() as u64).to_le_bytes())?;
+        stdout.write_all(&res)?;
+        stdout.flush()?;
+    }
+}

wireguard-broker/src/bin/socket_handler.rs

@@ -0,0 +1,191 @@
+use std::process::Stdio;
+
+use tokio::io::{AsyncReadExt, AsyncWriteExt};
+use tokio::net::{UnixListener, UnixStream};
+use tokio::process::Command;
+use tokio::sync::{mpsc, oneshot};
+use tokio::task;
+
+use anyhow::{bail, ensure, Result};
+use clap::{ArgGroup, Parser};
+
+use rosenpass_util::fd::claim_fd;
+use rosenpass_wireguard_broker::api::msgs;
+
+#[derive(Parser, Debug)]
+#[command(author, version, about, long_about = None)]
+#[clap(group(
+            ArgGroup::new("socket")
+                .required(true)
+                .args(&["listen_path", "listen_fd", "stream_fd"]),
+        ))]
+struct Args {
+    /// Where in the file-system to create the unix socket this broker will be listening for
+    /// connections on
+    #[arg(long)]
+    listen_path: Option<String>,
+
+    /// When this broker is called from another process, the other process can open and bind the
+    /// unix socket to use themselves, passing it to this process. In Rust this can be achieved
+    /// using the [command-fds](https://docs.rs/command-fds/latest/command_fds/) crate.
+    #[arg(long)]
+    listen_fd: Option<i32>,
+
+    /// When this broker is called from another process, the other process can connect the unix socket
+    /// themselves, for instance using the `socketpair(2)` system call.
+    #[arg(long)]
+    stream_fd: Option<i32>,
+
+    /// The underlying broker, accepting commands through stdin and sending results through stdout.
+    #[arg(
+        last = true,
+        allow_hyphen_values = true,
+        default_value = "rosenpass-wireguard-broker-privileged"
+    )]
+    command: Vec<String>,
+}
+
+struct BrokerRequest {
+    reply_to: oneshot::Sender<BrokerResponse>,
+    request: Vec<u8>,
+}
+
+struct BrokerResponse {
+    response: Vec<u8>,
+}
+
+#[tokio::main]
+async fn main() -> Result<()> {
+    env_logger::init();
+
+    let args = Args::parse();
+
+    let (proc_tx, proc_rx) = mpsc::channel(100);
+
+    // Start the inner broker handler
+    task::spawn(async move {
+        if let Err(e) = direct_broker_process(proc_rx, args.command).await {
+            log::error!("Error in broker command handler: {e}");
+            panic!("Can not proceed without underlying broker process");
+        }
+    });
+
+    // Listen for incoming requests
+    if let Some(path) = args.listen_path {
+        let sock = UnixListener::bind(path)?;
+        listen_for_clients(proc_tx, sock).await
+    } else if let Some(fd) = args.listen_fd {
+        let sock = std::os::unix::net::UnixListener::from(claim_fd(fd)?);
+        sock.set_nonblocking(true)?;
+        listen_for_clients(proc_tx, UnixListener::from_std(sock)?).await
+    } else if let Some(fd) = args.stream_fd {
+        let stream = std::os::unix::net::UnixStream::from(claim_fd(fd)?);
+        stream.set_nonblocking(true)?;
+        on_accept(proc_tx, UnixStream::from_std(stream)?).await
+    } else {
+        unreachable!();
+    }
+}
+
+async fn direct_broker_process(
+    mut queue: mpsc::Receiver<BrokerRequest>,
+    cmd: Vec<String>,
+) -> Result<()> {
+    let proc = Command::new(&cmd[0])
+        .args(&cmd[1..])
+        .stdin(Stdio::piped())
+        .stdout(Stdio::piped())
+        .spawn()?;
+
+    let mut stdin = proc.stdin.unwrap();
+    let mut stdout = proc.stdout.unwrap();
+
+    loop {
+        let BrokerRequest { reply_to, request } = queue.recv().await.unwrap();
+
+        stdin
+            .write_all(&(request.len() as u64).to_le_bytes())
+            .await?;
+        stdin.write_all(&request[..]).await?;
+
+        // Read the response length
+        let mut len = [0u8; 8];
+        stdout.read_exact(&mut len).await?;
+
+        // Parse the response length
+        let len = u64::from_le_bytes(len) as usize;
+        ensure!(
+            len <= msgs::RESPONSE_MSG_BUFFER_SIZE,
+            "Oversized buffer ({len}) in broker stdout."
+        );
+
+        // Read the message itself
+        let mut res_buf = request; // Avoid allocating memory if we don't have to
+        res_buf.resize(len as usize, 0);
+        stdout.read_exact(&mut res_buf[..len]).await?;
+
+        // Return to the unix socket connection worker
+        reply_to
+            .send(BrokerResponse { response: res_buf })
+            .or_else(|_| bail!("Unable to send respnse to unix socket worker."))?;
+    }
+}
+
+async fn listen_for_clients(queue: mpsc::Sender<BrokerRequest>, sock: UnixListener) -> Result<()> {
+    loop {
+        let (stream, _addr) = sock.accept().await?;
+        let queue = queue.clone();
+        task::spawn(async move {
+            if let Err(e) = on_accept(queue, stream).await {
+                log::error!("Error during connection processing: {e}");
+            }
+        });
+    }
+
+    // NOTE: If loop can ever terminate we need to join the spawned tasks
+}
+
+async fn on_accept(queue: mpsc::Sender<BrokerRequest>, mut stream: UnixStream) -> Result<()> {
+    let mut req_buf = Vec::new();
+
+    loop {
+        stream.readable().await?;
+
+        // Read the message length
+        let mut len = [0u8; 8];
+        stream.read_exact(&mut len).await?;
+
+        // Parse the message length
+        let len = u64::from_le_bytes(len) as usize;
+        ensure!(
+            len <= msgs::REQUEST_MSG_BUFFER_SIZE,
+            "Oversized buffer ({len}) in unix socket input."
+        );
+
+        // Read the message itself
+        req_buf.resize(len as usize, 0);
+        stream.read_exact(&mut req_buf[..len]).await?;
+
+        // Handle the message
+        let (reply_tx, reply_rx) = oneshot::channel();
+        queue
+            .send(BrokerRequest {
+                reply_to: reply_tx,
+                request: req_buf,
+            })
+            .await?;
+
+        // Wait for the reply
+        let BrokerResponse { response } = reply_rx.await.unwrap();
+
+        // Write reply back to unix socket
+        stream
+            .write_all(&(response.len() as u64).to_le_bytes())
+            .await?;
+        stream.write_all(&response[..]).await?;
+        stream.flush().await?;
+
+        // Reuse the same memory for the next message
+        req_buf = response;
+    }
+}

wireguard-broker/src/lib.rs

@@ -0,0 +1,14 @@
+use std::result::Result;
+
+pub trait WireGuardBroker {
+    type Error;
+
+    fn set_psk(
+        &mut self,
+        interface: &str,
+        peer_id: [u8; 32],
+        psk: [u8; 32],
+    ) -> Result<(), Self::Error>;
+}
+
+pub mod api;