Version v0.1.6

Fake Request Mode
Merge pull request #135 from alisharifi76/master
2025-12-17 04:44:36 +03:00 · 2019-10-31 22:36:29 +03:00 · 2019-10-31 22:36:12 +03:00 · 2019-04-03 01:33:02 +03:00 · 2019-03-29 22:32:05 +04:30 · 2019-02-18 01:33:03 +03:00
26 changed files with 1007 additions and 275 deletions
--- a/.editorconfig
+++ b/.editorconfig
@@ -0,0 +1,8 @@
+root = true
+
+[*]
+charset = utf-8
+indent_style = space
+indent_size = 4
+insert_final_newline = true
+end_of_line = lf
--- a/.github/ISSUE_TEMPLATE/bug-report----------------------.md
+++ b/.github/ISSUE_TEMPLATE/bug-report----------------------.md
@@ -0,0 +1,45 @@
+---
+name: Bug report / сообщение об ошибке
+about: Report software issue / сообщить об ошибке в программе
+title: ''
+labels: ''
+assignees: ''
+
+---
+
+<!--
+WARNING! Please pay some attention!
+GoodbyeDPI does not guarantee to work on your ISP on 100% or at all. If GoodbyeDPI can't unblock some or any websites, this is most likely not a software bug, and you should not report it.
+Please report software bugs, such as: website incompatibility (if the website works without GoodbyeDPI but breaks with GoobyeDPI enabled), antivirus incompatibility, DNS redirection problems, incorrect packet handling, and other software issues.
+Please make sure to check other opened and closed issues, it could be your question or issue has been already discussed.
+
+ВНИМАНИЕ! Пожалуйста, прочтите!
+GoodbyeDPI не гарантирует ни 100% работу с вашим провайдером, ни работу вообще. Если GoodbyeDPI не разблокирует доступ к некоторым или всем веб-сайтам, вероятнее всего, это не программная ошибка, и не стоит о ней сообщать здесь.
+Сообщайте только об ошибках в программе, таких как: некорректная работа с веб-сайтами (когда веб-сайт работает без GoodbyeDPI, но ломается с GoodbyeDPI), несовместимость с антивирусами, проблемы с перенаправлением DNS, некорректная обработка пакетов, и другие проблемы.
+Также посмотрите другие открытые и закрытые баги. Возможно, ваш вопрос или проблема уже обсуждались.
+-->
+
+**Describe the bug / Опишите проблему**
+A clear and concise description of what the bug is. If the issue about software incompatibility, include your operating system version and software name/version.
+Подробно опишите, в чём заключается проблема. Если проблема касается совместимости с другими программами, укажите версию вашей операционной системы, имя и версию программы.
+
+**To Reproduce / Шаги воспроизведения проблемы**
+Steps to reproduce the behavior:
+1. Go to '...'
+2. Click on '....'
+3. Scroll down to '....'
+4. See error
+
+**Expected behavior / ожидаемое поведение программы**
+A clear and concise description of what you expected to happen.
+Подробно опишите, как вы ожидаете, чтобы программа работала.
+
+**Actual behavior / текущее поведение программы**
+A clear and concise description of what you expected to happen.
+Подробно опишите, что происходит с программой на текущий момент.
+
+**Screenshots / Скриншоты**
+If applicable, add screenshots to help explain your problem.
+Если необходимо, добавьте скриншоты, объясняющие проблему.
+
+**Additional context / дополнительная информация**
--- a/.github/ISSUE_TEMPLATE/feature-request------------------------------------.md
+++ b/.github/ISSUE_TEMPLATE/feature-request------------------------------------.md
@@ -0,0 +1,12 @@
+---
+name: Feature request / предложить новую функциональность
+about: Suggest an idea or function for this project / предложить новую идею или функциональность
+title: ''
+labels: ''
+assignees: ''
+
+---
+
+**Description / Описание**
+A clear and concise description of your suggestion.
+Детальное описание вашего предложения.
--- a/37
+++ b/37
@@ -1,37 +0,0 @@
-ifndef MSYSTEM
-	CPREFIX = x86_64-w64-mingw32-
-endif
-
-WINDIVERTHEADERS = ../../include
-WINDIVERTLIBS = ../binary
-
-TARGET = goodbyedpi.exe
-LIBS = -L$(WINDIVERTLIBS) -lWinDivert -lws2_32
-CC = $(CPREFIX)gcc
-CCWINDRES = $(CPREFIX)windres
-CFLAGS = -Wall -Wextra -I$(WINDIVERTHEADERS) -L$(WINDIVERTLIBS) \
-         -O2 -pie -fPIE -Wformat -Werror=format-security -D_FORTIFY_SOURCE=2
-LDFLAGS = -Wl,-O1,--sort-common,--as-needed
-
-.PHONY: default all clean
-
-default: manifest $(TARGET)
-all: default
-
-OBJECTS = $(patsubst %.c, %.o, $(wildcard *.c)) goodbyedpi-rc.o
-HEADERS = $(wildcard *.h)
-
-%.o: %.c $(HEADERS)
-	$(CC) $(CFLAGS) -c $< -o $@
-
-manifest:
-	$(CCWINDRES) goodbyedpi-rc.rc goodbyedpi-rc.o
-
-.PRECIOUS: $(TARGET) $(OBJECTS)
-
-$(TARGET): $(OBJECTS)
-	$(CC) $(OBJECTS) -Wall $(LDFLAGS) $(LIBS) -s -o $@
-
-clean:
-	-rm -f *.o
-	-rm -f $(TARGET)
--- a/README.md
+++ b/README.md
@@ -23,12 +23,20 @@ Usage: goodbyedpi.exe [OPTION...]
 -e [value]  set HTTPS fragmentation to value
 -a          additional space between Method and Request-URI (enables -s, may break sites)
 -w          try to find and parse HTTP traffic on all processed ports (not only on port 80)
- --port      [value]    additional TCP port to perform fragmentation on (and HTTP tricks with -w)
- --dns-addr  [value]    redirect UDP DNS requests to the supplied IP address (experimental)
- --dns-port  [value]    redirect UDP DNS requests to the supplied port (53 by default)
- --dns-verb             print verbose DNS redirection messages
- --blacklist [txtfile]  perform HTTP tricks only to host names and subdomains from
-                        supplied text file. This option can be supplied multiple times.
+ --port        [value]    additional TCP port to perform fragmentation on (and HTTP tricks with -w)
+ --ip-id       [value]    handle additional IP ID (decimal, drop redirects and TCP RSTs with this ID).
+                          This option can be supplied multiple times.
+ --dns-addr    [value]    redirect UDP DNS requests to the supplied IP address (experimental)
+ --dns-port    [value]    redirect UDP DNS requests to the supplied port (53 by default)
+ --dnsv6-addr  [value]    redirect UDPv6 DNS requests to the supplied IPv6 address (experimental)
+ --dnsv6-port  [value]    redirect UDPv6 DNS requests to the supplied port (53 by default)
+ --dns-verb               print verbose DNS redirection messages
+ --blacklist   [txtfile]  perform HTTP tricks only to host names and subdomains from
+                          supplied text file. This option can be supplied multiple times.
+ --set-ttl     [value]    activate Fake Request Mode and send it with supplied TTL value.
+                          DANGEROUS! May break websites in unexpected ways. Use with care.
+ --wrong-chksum           activate Fake Request Mode and send it with incorrect TCP checksum.
+                          May not work in a VM or with some routers, but is safer than set-ttl.

 -1          -p -r -s -f 2 -k 2 -n -e 2 (most compatible mode, default)
 -2          -p -r -s -f 2 -k 2 -n -e 40 (better speed for HTTPS yet still compatible)
@@ -48,11 +56,11 @@ Use `goodbyedpi.exe -4` if it works for your ISP's DPI. This is the fastest mode

 ### Passive DPI

-Most Passive DPI send HTTP 302 Redirect if you try to access blocked website over HTTP and TCP Reset in case of HTTPS, faster than destination website. Packets sent by DPI always have IP Identification field equal to `0x0000` or `0x0001`, as seen with Russian providers. These packets, if they redirect you to another website (censorship page), are blocked by GoodbyeDPI.
+Most Passive DPI send HTTP 302 Redirect if you try to access blocked website over HTTP and TCP Reset in case of HTTPS, faster than destination website. Packets sent by DPI usually have IP Identification field equal to `0x0000` or `0x0001`, as seen with Russian providers. These packets, if they redirect you to another website (censorship page), are blocked by GoodbyeDPI.

 ### Active DPI

-Active DPI is more tricky to fool. Currently the software uses 4 methods to circumvent Active DPI:
+Active DPI is more tricky to fool. Currently the software uses 7 methods to circumvent Active DPI:

 * TCP-level fragmentation for first data packet
 * TCP-level fragmentation for persistent (keep-alive) HTTP sessions
@@ -60,6 +68,7 @@ Active DPI is more tricky to fool. Currently the software uses 4 methods to circ
 * Removing space between header name and value in `Host` header
 * Adding additional space between HTTP Method (GET, POST etc) and URI
 * Mixing case of Host header value
+* Sending fake HTTP/HTTPS packets with low Time-To-Live value or incorrect checksum to fool DPI and prevent delivering them to the destination

 These methods should not break any website as they're fully compatible with TCP and HTTP standards, yet it's sufficient to prevent DPI data classification and to circumvent censorship. Additional space may break some websites, although it's acceptable by HTTP/1.1 specification (see 19.3 Tolerant Applications).

@@ -75,16 +84,24 @@ To build x86 exe run:

 And for x86_64:

-`make CPREFIX=x86_64-w64-mingw32- WINDIVERTHEADERS=/path/to/windivert/include WINDIVERTLIBS=/path/to/windivert/amd64`
+`make CPREFIX=x86_64-w64-mingw32- BIT64=1 WINDIVERTHEADERS=/path/to/windivert/include WINDIVERTLIBS=/path/to/windivert/amd64`

 # How to install as Windows Service

 Use `service_install_russia_blacklist.cmd`, `service_install_russia_blacklist_dnsredir.cmd` and `service_remove.cmd` scripts.  
 Modify them according to your own needs.

+# Known issues
+
+* Horribly outdated Windows 7 installations are not able to load WinDivert driver due to missing support for SHA256 digital signatures. Install KB3033929 [x86](https://www.microsoft.com/en-us/download/details.aspx?id=46078)/[x64](https://www.microsoft.com/en-us/download/details.aspx?id=46148), or better, update the whole system using Windows Update.
+* Some SSL/TLS stacks unable to process fragmented ClientHello packets, and HTTPS websites won't open. Bug: [#4](https://github.com/ValdikSS/GoodbyeDPI/issues/4), [#64](https://github.com/ValdikSS/GoodbyeDPI/issues/64).
+* ESET Antivirus is incompatible with WinDivert driver [#91](https://github.com/ValdikSS/GoodbyeDPI/issues/91). This is most probably antivirus bug, not WinDivert.
+
+
 # Similar projects

-[zapret](https://github.com/bol-van/zapret) by @bol-van (for Linux).
+- **[zapret](https://github.com/bol-van/zapret)** by @bol-van (for Linux).
+- **[Green Tunnel](https://github.com/SadeghHayeri/GreenTunnel)** by @SadeghHayeri (for MacOS, Linux and Windows).

 # Kudos

--- a/blackwhitelist.h
+++ b/blackwhitelist.h
@@ -1,2 +0,0 @@
-int blackwhitelist_load_list(const char *filename);
-int blackwhitelist_check_hostname(const char *host_addr, int host_len);
--- a/dnsredir.h
+++ b/dnsredir.h
@@ -1,19 +0,0 @@
-#include <stdint.h>
-
-typedef struct conntrack_info {
-    uint32_t srcip;
-    uint16_t srcport;
-    uint32_t dstip;
-    uint16_t dstport;
-} conntrack_info_t;
-
-int dns_handle_incoming(const uint32_t srcip, const uint16_t srcport,
-                        const char *packet_data, const UINT packet_dataLen,
-                        conntrack_info_t *conn_info);
-
-int dns_handle_outgoing(const uint32_t srcip, const uint16_t srcport,
-                        const uint32_t dstip, const uint16_t dstport,
-                        const char *packet_data, const UINT packet_dataLen);
-
-void flush_dns_cache();
-int dns_is_dns_packet(const char *packet_data, const UINT packet_dataLen, const int outgoing);
--- a/src/Makefile
+++ b/src/Makefile
@@ -0,0 +1,50 @@
+ifndef MSYSTEM
+	CPREFIX = x86_64-w64-mingw32-
+endif
+
+WINDIVERTHEADERS = ../../../include
+WINDIVERTLIBS = ../../binary
+MINGWLIB = /usr/x86_64-w64-mingw32/lib/
+
+TARGET = goodbyedpi.exe
+# Linking SSP does not work for some reason, the executable doesn't start.
+#LIBS = -L$(WINDIVERTLIBS) -Wl,-Bstatic -lssp -Wl,-Bdynamic -lWinDivert -lws2_32
+LIBS = -L$(WINDIVERTLIBS) -lWinDivert -lws2_32
+CC = $(CPREFIX)gcc
+CCWINDRES = $(CPREFIX)windres
+CFLAGS = -std=c99 -pie -fPIE -pipe -I$(WINDIVERTHEADERS) -L$(WINDIVERTLIBS) \
+         -O2 -D_FORTIFY_SOURCE=2 \
+         -Wall -Wextra -Wpedantic -Wformat=2 -Wshadow -Wstrict-aliasing=1 -Werror=format-security \
+         -Wfloat-equal -Wcast-align -Wsign-conversion \
+         #-fstack-protector-strong
+LDFLAGS = -Wl,-O1,-pie,--dynamicbase,--nxcompat,--sort-common,--as-needed \
+-Wl,--image-base,0x140000000 -Wl,--disable-auto-image-base
+
+ifdef BIT64
+	LDFLAGS += -Wl,--high-entropy-va -Wl,--pic-executable,-e,mainCRTStartup
+else
+	LDFLAGS += -Wl,--pic-executable,-e,_mainCRTStartup
+endif
+
+.PHONY: default all clean
+
+default: manifest $(TARGET)
+all: default
+
+OBJECTS = $(patsubst %.c, %.o, $(wildcard *.c utils/*.c)) goodbyedpi-rc.o
+HEADERS = $(wildcard *.h utils/*.h)
+
+%.o: %.c $(HEADERS)
+	$(CC) $(CFLAGS) -c $< -o $@
+
+manifest:
+	$(CCWINDRES) goodbyedpi-rc.rc goodbyedpi-rc.o
+
+.PRECIOUS: $(TARGET) $(OBJECTS)
+
+$(TARGET): $(OBJECTS)
+	$(CC) $(OBJECTS) $(LDFLAGS) $(LIBS) -s -o $@
+
+clean:
+	-rm -f *.o utils/*.o
+	-rm -f $(TARGET)
--- a/src/blackwhitelist.c
+++ b/src/blackwhitelist.c
@@ -8,8 +8,8 @@
 #include <windows.h>
 #include <stdio.h>
 #include "goodbyedpi.h"
-#include "uthash.h"
-#include "getline.h"
+#include "utils/uthash.h"
+#include "utils/getline.h"

 typedef struct blackwhitelist_record {
    const char *host;
@@ -84,7 +84,7 @@ int blackwhitelist_load_list(const char *filename) {
    return TRUE;
 }

-int blackwhitelist_check_hostname(const char *host_addr, int host_len) {
+int blackwhitelist_check_hostname(const char *host_addr, size_t host_len) {
    char current_host[HOST_MAXLEN + 1];
    char *tokenized_host = NULL;

--- a/src/blackwhitelist.h
+++ b/src/blackwhitelist.h
@@ -0,0 +1,2 @@
+int blackwhitelist_load_list(const char *filename);
+int blackwhitelist_check_hostname(const char *host_addr, size_t host_len);
--- a/src/dnsredir.c
+++ b/src/dnsredir.c
@@ -15,10 +15,10 @@
 #include <stdio.h>
 #include "goodbyedpi.h"
 #include "dnsredir.h"
-#include "uthash.h"
+#include "utils/uthash.h"

-// IPv6 incompatible!
-#define UDP_CONNRECORD_KEY_LEN 6
+/* key ('4' for IPv4 or '6' for IPv6 + srcip[16] + srcport[2]) */
+#define UDP_CONNRECORD_KEY_LEN 19

 #define DNS_CLEANUP_INTERVAL_SEC 30

@@ -32,10 +32,10 @@
 #define uthash_strlen(s) UDP_CONNRECORD_KEY_LEN

 typedef struct udp_connrecord {
-    /* key (srcip[4] + srcport[2]) */
+    /* key ('4' for IPv4 or '6' for IPv6 + srcip[16] + srcport[2]) */
    char key[UDP_CONNRECORD_KEY_LEN];
    time_t time;         /* time when this record was added */
-    uint32_t dstip;
+    uint32_t dstip[4];
    uint16_t dstport;
    UT_hash_handle hh;   /* makes this structure hashable */
 } udp_connrecord_t;
@@ -59,26 +59,60 @@ void flush_dns_cache() {
    FreeLibrary(dnsapi);
 }

-inline static void construct_key(const uint32_t srcip, const uint16_t srcport, char *key) {
+inline static void fill_key_data(char *key, const uint8_t is_ipv6, const uint32_t srcip[4],
+                          const uint16_t srcport)
+{
+    if (is_ipv6) {
+        *(uint8_t*)(key) = '6';
+        ipv6_copy_addr((uint32_t*)(key + sizeof(uint8_t)), srcip);
+    }
+    else {
+        *(uint8_t*)(key) = '4';
+        ipv4_copy_addr((uint32_t*)(key + sizeof(uint8_t)), srcip);
+    }
+
+    *(uint16_t*)(key + sizeof(uint8_t) + sizeof(uint32_t) * 4) = srcport;
+}
+
+inline static void fill_data_from_key(uint8_t *is_ipv6, uint32_t srcip[4], uint16_t *srcport,
+                                      const char *key)
+{
+    if (key[0] == '6') {
+        *is_ipv6 = 1;
+        ipv6_copy_addr(srcip, (uint32_t*)(key + sizeof(uint8_t)));
+    }
+    else {
+        *is_ipv6 = 0;
+        ipv4_copy_addr(srcip, (uint32_t*)(key + sizeof(uint8_t)));
+    }
+    *srcport = *(uint16_t*)(key + sizeof(uint8_t) + sizeof(uint32_t) * 4);
+}
+
+inline static void construct_key(const uint32_t srcip[4], const uint16_t srcport,
+                                 char *key, const uint8_t is_ipv6)
+{
    debug("Construct key enter\n");
    if (key) {
        debug("Constructing key\n");
-
-        *(uint32_t*)(key) = srcip;
-        *(uint16_t*)(key + sizeof(srcip)) = srcport;
+        fill_key_data(key, is_ipv6, srcip, srcport);
    }
    debug("Construct key end\n");
 }

-inline static void deconstruct_key(const char *key, udp_connrecord_t *connrecord,
-                                   conntrack_info_t *conn_info) {
+inline static void deconstruct_key(const char *key, const udp_connrecord_t *connrecord,
+                                   conntrack_info_t *conn_info)
+{
    debug("Deconstruct key enter\n");
    if (key && conn_info) {
        debug("Deconstructing key\n");
+        fill_data_from_key(&conn_info->is_ipv6, conn_info->srcip,
+                           &conn_info->srcport, key);
+
+        if (conn_info->is_ipv6)
+            ipv6_copy_addr(conn_info->dstip, connrecord->dstip);
+        else
+            ipv4_copy_addr(conn_info->dstip, connrecord->dstip);

-        conn_info->srcip = *(uint32_t*)(key);
-        conn_info->srcport = *(uint16_t*)(key + sizeof(conn_info->srcip));
-        conn_info->dstip = connrecord->dstip;
        conn_info->dstport = connrecord->dstport;
    }
    debug("Deconstruct key end\n");
@@ -99,17 +133,26 @@ static int check_get_udp_conntrack_key(const char *key, udp_connrecord_t **connr
    return FALSE;
 }

-static int add_udp_conntrack(const uint32_t srcip, const uint16_t srcport,
-                             const uint32_t dstip, const uint16_t dstport) {
+static int add_udp_conntrack(const uint32_t srcip[4], const uint16_t srcport,
+                             const uint32_t dstip[4], const uint16_t dstport,
+                             const uint8_t is_ipv6
+                            )
+{
    if (!(srcip && srcport && dstip && dstport))
        return FALSE;

    udp_connrecord_t *tmp_connrecord = malloc(sizeof(udp_connrecord_t));
-    construct_key(srcip, srcport, tmp_connrecord->key);
+    construct_key(srcip, srcport, tmp_connrecord->key, is_ipv6);

    if (!check_get_udp_conntrack_key(tmp_connrecord->key, NULL)) {
        tmp_connrecord->time = time(NULL);
-        tmp_connrecord->dstip = dstip;
+
+        if (is_ipv6) {
+            ipv6_copy_addr(tmp_connrecord->dstip, dstip);
+        }
+        else {
+            ipv4_copy_addr(tmp_connrecord->dstip, dstip);
+        }
        tmp_connrecord->dstport = dstport;
        HASH_ADD_STR(conntrack, key, tmp_connrecord);
        debug("Added UDP conntrack\n");
@@ -120,7 +163,7 @@ static int add_udp_conntrack(const uint32_t srcip, const uint16_t srcport,
    return FALSE;
 }

-void dns_cleanup() {
+static void dns_cleanup() {
    udp_connrecord_t *tmp_connrecord, *tmp_connrecord2 = NULL;

    if (last_cleanup == 0) {
@@ -154,10 +197,11 @@ int dns_is_dns_packet(const char *packet_data, const UINT packet_dataLen, const
    return FALSE;
 }

-int dns_handle_outgoing(const uint32_t srcip, const uint16_t srcport,
-                        const uint32_t dstip, const uint16_t dstport,
-                        const char *packet_data, const UINT packet_dataLen) {
-
+int dns_handle_outgoing(const uint32_t srcip[4], const uint16_t srcport,
+                        const uint32_t dstip[4], const uint16_t dstport,
+                        const char *packet_data, const UINT packet_dataLen,
+                        const uint8_t is_ipv6)
+{
    if (packet_dataLen < 16)
        return FALSE;

@@ -166,16 +210,16 @@ int dns_handle_outgoing(const uint32_t srcip, const uint16_t srcport,
    if (dns_is_dns_packet(packet_data, packet_dataLen, 1)) {
        /* Looks like DNS request */
        debug("trying to add srcport = %hu, dstport = %hu\n", ntohs(srcport), ntohs(dstport));
-        return add_udp_conntrack(srcip, srcport, dstip, dstport);
+        return add_udp_conntrack(srcip, srcport, dstip, dstport, is_ipv6);
    }
    debug("____dns_handle_outgoing FALSE: srcport = %hu, dstport = %hu\n", ntohs(srcport), ntohs(dstport));
    return FALSE;
 }

-int dns_handle_incoming(const uint32_t srcip, const uint16_t srcport,
+int dns_handle_incoming(const uint32_t srcip[4], const uint16_t srcport,
                        const char *packet_data, const UINT packet_dataLen,
-                        conntrack_info_t *conn_info) {
-
+                        conntrack_info_t *conn_info, const uint8_t is_ipv6)
+{
    char key[UDP_CONNRECORD_KEY_LEN];
    udp_connrecord_t *tmp_connrecord = NULL;

@@ -186,7 +230,7 @@ int dns_handle_incoming(const uint32_t srcip, const uint16_t srcport,

    if (dns_is_dns_packet(packet_data, packet_dataLen, 0)) {
        /* Looks like DNS response */
-        construct_key(srcip, srcport, key);
+        construct_key(srcip, srcport, key, is_ipv6);
        if (check_get_udp_conntrack_key(key, &tmp_connrecord) && tmp_connrecord) {
            /* Connection exists in conntrack, moving on */
            deconstruct_key(key, tmp_connrecord, conn_info);
@@ -195,6 +239,6 @@ int dns_handle_incoming(const uint32_t srcip, const uint16_t srcport,
            return TRUE;
        }
    }
-    debug("____dns_handle_incoming FALSE: srcport = %hu, dstport = %hu\n", ntohs(srcport), ntohs(dstport));
+    debug("____dns_handle_incoming FALSE: srcport = %hu\n", ntohs(srcport));
    return FALSE;
 }
--- a/src/dnsredir.h
+++ b/src/dnsredir.h
@@ -0,0 +1,36 @@
+#include <stdint.h>
+
+typedef struct conntrack_info {
+    uint8_t  is_ipv6;
+    uint32_t srcip[4];
+    uint16_t srcport;
+    uint32_t dstip[4];
+    uint16_t dstport;
+} conntrack_info_t;
+
+inline static void ipv4_copy_addr(uint32_t dst[4], const uint32_t src[4]) {
+    dst[0] = src[0];
+    dst[1] = 0;
+    dst[2] = 0;
+    dst[3] = 0;
+}
+
+inline static void ipv6_copy_addr(uint32_t dst[4], const uint32_t src[4]) {
+    dst[0] = src[0];
+    dst[1] = src[1];
+    dst[2] = src[2];
+    dst[3] = src[3];
+}
+
+int dns_handle_incoming(const uint32_t srcip[4], const uint16_t srcport,
+                        const char *packet_data, const UINT packet_dataLen,
+                        conntrack_info_t *conn_info, const uint8_t is_ipv6);
+
+int dns_handle_outgoing(const uint32_t srcip[4], const uint16_t srcport,
+                        const uint32_t dstip[4], const uint16_t dstport,
+                        const char *packet_data, const UINT packet_dataLen,
+                        const uint8_t is_ipv6
+                       );
+
+void flush_dns_cache();
+int dns_is_dns_packet(const char *packet_data, const UINT packet_dataLen, const int outgoing);
--- a/src/fakepackets.c
+++ b/src/fakepackets.c
@@ -0,0 +1,166 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <ctype.h>
+#include <unistd.h>
+#include <in6addr.h>
+#include <ws2tcpip.h>
+#include "windivert.h"
+#include "goodbyedpi.h"
+
+static const char fake_http_request[] = "GET / HTTP/1.1\r\nHost: www.w3.org\r\n"
+                                        "User-Agent: curl/7.65.3\r\nAccept: */*\r\n"
+                                        "Accept-Encoding: deflate, gzip, br\r\n\r\n";
+static const unsigned char fake_https_request[] = {
+    0x16, 0x03, 0x01, 0x02, 0x00, 0x01, 0x00, 0x01, 0xfc, 0x03, 0x03, 0x9a, 0x8f, 0xa7, 0x6a, 0x5d,
+    0x57, 0xf3, 0x62, 0x19, 0xbe, 0x46, 0x82, 0x45, 0xe2, 0x59, 0x5c, 0xb4, 0x48, 0x31, 0x12, 0x15,
+    0x14, 0x79, 0x2c, 0xaa, 0xcd, 0xea, 0xda, 0xf0, 0xe1, 0xfd, 0xbb, 0x20, 0xf4, 0x83, 0x2a, 0x94,
+    0xf1, 0x48, 0x3b, 0x9d, 0xb6, 0x74, 0xba, 0x3c, 0x81, 0x63, 0xbc, 0x18, 0xcc, 0x14, 0x45, 0x57,
+    0x6c, 0x80, 0xf9, 0x25, 0xcf, 0x9c, 0x86, 0x60, 0x50, 0x31, 0x2e, 0xe9, 0x00, 0x22, 0x13, 0x01,
+    0x13, 0x03, 0x13, 0x02, 0xc0, 0x2b, 0xc0, 0x2f, 0xcc, 0xa9, 0xcc, 0xa8, 0xc0, 0x2c, 0xc0, 0x30,
+    0xc0, 0x0a, 0xc0, 0x09, 0xc0, 0x13, 0xc0, 0x14, 0x00, 0x33, 0x00, 0x39, 0x00, 0x2f, 0x00, 0x35,
+    0x01, 0x00, 0x01, 0x91, 0x00, 0x00, 0x00, 0x0f, 0x00, 0x0d, 0x00, 0x00, 0x0a, 0x77, 0x77, 0x77,
+    0x2e, 0x77, 0x33, 0x2e, 0x6f, 0x72, 0x67, 0x00, 0x17, 0x00, 0x00, 0xff, 0x01, 0x00, 0x01, 0x00,
+    0x00, 0x0a, 0x00, 0x0e, 0x00, 0x0c, 0x00, 0x1d, 0x00, 0x17, 0x00, 0x18, 0x00, 0x19, 0x01, 0x00,
+    0x01, 0x01, 0x00, 0x0b, 0x00, 0x02, 0x01, 0x00, 0x00, 0x23, 0x00, 0x00, 0x00, 0x10, 0x00, 0x0e,
+    0x00, 0x0c, 0x02, 0x68, 0x32, 0x08, 0x68, 0x74, 0x74, 0x70, 0x2f, 0x31, 0x2e, 0x31, 0x00, 0x05,
+    0x00, 0x05, 0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x33, 0x00, 0x6b, 0x00, 0x69, 0x00, 0x1d, 0x00,
+    0x20, 0xb0, 0xe4, 0xda, 0x34, 0xb4, 0x29, 0x8d, 0xd3, 0x5c, 0x70, 0xd3, 0xbe, 0xe8, 0xa7, 0x2a,
+    0x6b, 0xe4, 0x11, 0x19, 0x8b, 0x18, 0x9d, 0x83, 0x9a, 0x49, 0x7c, 0x83, 0x7f, 0xa9, 0x03, 0x8c,
+    0x3c, 0x00, 0x17, 0x00, 0x41, 0x04, 0x4c, 0x04, 0xa4, 0x71, 0x4c, 0x49, 0x75, 0x55, 0xd1, 0x18,
+    0x1e, 0x22, 0x62, 0x19, 0x53, 0x00, 0xde, 0x74, 0x2f, 0xb3, 0xde, 0x13, 0x54, 0xe6, 0x78, 0x07,
+    0x94, 0x55, 0x0e, 0xb2, 0x6c, 0xb0, 0x03, 0xee, 0x79, 0xa9, 0x96, 0x1e, 0x0e, 0x98, 0x17, 0x78,
+    0x24, 0x44, 0x0c, 0x88, 0x80, 0x06, 0x8b, 0xd4, 0x80, 0xbf, 0x67, 0x7c, 0x37, 0x6a, 0x5b, 0x46,
+    0x4c, 0xa7, 0x98, 0x6f, 0xb9, 0x22, 0x00, 0x2b, 0x00, 0x09, 0x08, 0x03, 0x04, 0x03, 0x03, 0x03,
+    0x02, 0x03, 0x01, 0x00, 0x0d, 0x00, 0x18, 0x00, 0x16, 0x04, 0x03, 0x05, 0x03, 0x06, 0x03, 0x08,
+    0x04, 0x08, 0x05, 0x08, 0x06, 0x04, 0x01, 0x05, 0x01, 0x06, 0x01, 0x02, 0x03, 0x02, 0x01, 0x00,
+    0x2d, 0x00, 0x02, 0x01, 0x01, 0x00, 0x1c, 0x00, 0x02, 0x40, 0x01, 0x00, 0x15, 0x00, 0x96, 0x00,
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+    0x00, 0x00, 0x00, 0x00, 0x00
+};
+
+static int send_fake_data(const HANDLE w_filter,
+                          const PWINDIVERT_ADDRESS addr,
+                          const char *pkt,
+                          const UINT packetLen,
+                          const BOOL is_ipv6,
+                          const BOOL is_https,
+                          const BYTE set_ttl,
+                          const BYTE set_checksum
+                         ) {
+    char packet_fake[MAX_PACKET_SIZE];
+    WINDIVERT_ADDRESS addr_new;
+    PVOID packet_data;
+    UINT packet_dataLen;
+    UINT packetLen_new;
+    PWINDIVERT_IPHDR ppIpHdr;
+    PWINDIVERT_IPV6HDR ppIpV6Hdr;
+    PWINDIVERT_TCPHDR ppTcpHdr;
+    char *fake_request_data = is_https ? fake_https_request : fake_http_request;
+    UINT fake_request_size = is_https ? sizeof(fake_https_request) : sizeof(fake_http_request) - 1;
+
+    memcpy(&addr_new, addr, sizeof(WINDIVERT_ADDRESS));
+    memcpy(packet_fake, pkt, packetLen);
+
+    if (!is_ipv6) {
+        // IPv4 TCP Data packet
+        if (!WinDivertHelperParsePacket(packet_fake, packetLen, &ppIpHdr,
+            NULL, NULL, NULL, &ppTcpHdr, NULL, &packet_data, &packet_dataLen))
+            return 1;
+    }
+    else {
+        // IPv6 TCP Data packet
+        if (!WinDivertHelperParsePacket(packet_fake, packetLen, NULL,
+            &ppIpV6Hdr, NULL, NULL, &ppTcpHdr, NULL, &packet_data, &packet_dataLen))
+            return 1;
+    }
+
+    if (packetLen + fake_request_size + 1 > MAX_PACKET_SIZE)
+        return 2;
+
+    memcpy(packet_data, fake_request_data, fake_request_size);
+    packetLen_new = packetLen - packet_dataLen + fake_request_size;
+
+    if (!is_ipv6) {
+        ppIpHdr->Length = htons(
+            ntohs(ppIpHdr->Length) -
+            packet_dataLen + fake_request_size
+        );
+
+        if (set_ttl)
+            ppIpHdr->TTL = set_ttl;
+    }
+    else {
+        ppIpV6Hdr->Length = htons(
+            ntohs(ppIpV6Hdr->Length) -
+            packet_dataLen + fake_request_size
+        );
+
+        if (set_ttl)
+            ppIpV6Hdr->HopLimit = set_ttl;
+    }
+
+    // Recalculate the checksum
+    addr_new.PseudoTCPChecksum = 0;
+    WinDivertHelperCalcChecksums(packet_fake, packetLen_new, &addr_new, NULL);
+
+    if (set_checksum) {
+        // ...and damage it
+        ppTcpHdr->Checksum = htons(ntohs(ppTcpHdr->Checksum) - 1);
+    }
+    //printf("Pseudo checksum: %d\n", addr_new.PseudoTCPChecksum);
+
+    WinDivertSend(
+        w_filter, packet_fake,
+        packetLen_new,
+        &addr_new, NULL
+    );
+    debug("Fake packet: OK");
+
+    return 0;
+}
+
+int send_fake_http_request(const HANDLE w_filter,
+                                  const PWINDIVERT_ADDRESS addr,
+                                  const char *pkt,
+                                  const UINT packetLen,
+                                  const BOOL is_ipv6,
+                                  const BYTE set_ttl,
+                                  const BYTE set_checksum
+                                 ) {
+    return send_fake_data(w_filter,
+                          addr,
+                          pkt,
+                          packetLen,
+                          is_ipv6,
+                          FALSE,
+                          set_ttl,
+                          set_checksum
+           );
+}
+
+int send_fake_https_request(const HANDLE w_filter,
+                                   const PWINDIVERT_ADDRESS addr,
+                                   const char *pkt,
+                                   const UINT packetLen,
+                                   const BOOL is_ipv6,
+                                   const BYTE set_ttl,
+                                   const BYTE set_checksum
+                                 ) {
+    return send_fake_data(w_filter,
+                          addr,
+                          pkt,
+                          packetLen,
+                          is_ipv6,
+                          TRUE,
+                          set_ttl,
+                          set_checksum
+           );
+}
--- a/src/fakepackets.h
+++ b/src/fakepackets.h
@@ -0,0 +1,16 @@
+int send_fake_http_request(const HANDLE w_filter,
+                                  const PWINDIVERT_ADDRESS addr,
+                                  const char *pkt,
+                                  const UINT packetLen,
+                                  const BOOL is_ipv6,
+                                  const BYTE set_ttl,
+                                  const BYTE set_checksum
+                                 );
+int send_fake_https_request(const HANDLE w_filter,
+                                   const PWINDIVERT_ADDRESS addr,
+                                   const char *pkt,
+                                   const UINT packetLen,
+                                   const BOOL is_ipv6,
+                                   const BYTE set_ttl,
+                                   const BYTE set_checksum
+                                 );
--- a/src/goodbyedpi-rc.rc
+++ b/src/goodbyedpi-rc.rc
--- a/src/goodbyedpi.c
+++ b/src/goodbyedpi.c
@@ -9,27 +9,33 @@
 #include <unistd.h>
 #include <string.h>
 #include <getopt.h>
+#include <in6addr.h>
+#include <ws2tcpip.h>
 #include "windivert.h"
 #include "goodbyedpi.h"
+#include "utils/repl_str.h"
 #include "service.h"
 #include "dnsredir.h"
 #include "blackwhitelist.h"
+#include "fakepackets.h"

-#define die() do { printf("Something went wrong!\n" \
-    "Make sure you're running this program with administrator privileges\n"); \
-    sleep(10); exit(EXIT_FAILURE); } while (0)
+// My mingw installation does not load inet_pton definition for some reason
+WINSOCK_API_LINKAGE INT WSAAPI inet_pton(INT Family, LPCSTR pStringBuf, PVOID pAddr);
+
+#define GOODBYEDPI_VERSION "v0.1.6"
+
+#define die() do { sleep(20); exit(EXIT_FAILURE); } while (0)

 #define MAX_FILTERS 4
-#define MAX_PACKET_SIZE 9016

-#define DIVERT_NO_LOCALNETS_DST "(" \
+#define DIVERT_NO_LOCALNETSv4_DST "(" \
                   "(ip.DstAddr < 127.0.0.1 or ip.DstAddr > 127.255.255.255) and " \
                   "(ip.DstAddr < 10.0.0.0 or ip.DstAddr > 10.255.255.255) and " \
                   "(ip.DstAddr < 192.168.0.0 or ip.DstAddr > 192.168.255.255) and " \
                   "(ip.DstAddr < 172.16.0.0 or ip.DstAddr > 172.31.255.255) and " \
                   "(ip.DstAddr < 169.254.0.0 or ip.DstAddr > 169.254.255.255)" \
                   ")"
-#define DIVERT_NO_LOCALNETS_SRC "(" \
+#define DIVERT_NO_LOCALNETSv4_SRC "(" \
                   "(ip.SrcAddr < 127.0.0.1 or ip.SrcAddr > 127.255.255.255) and " \
                   "(ip.SrcAddr < 10.0.0.0 or ip.SrcAddr > 10.255.255.255) and " \
                   "(ip.SrcAddr < 192.168.0.0 or ip.SrcAddr > 192.168.255.255) and " \
@@ -37,13 +43,48 @@
                   "(ip.SrcAddr < 169.254.0.0 or ip.SrcAddr > 169.254.255.255)" \
                   ")"

+#define DIVERT_NO_LOCALNETSv6_DST "(" \
+                   "(ipv6.DstAddr > ::1) and " \
+                   "(ipv6.DstAddr < 2001::0 or ipv6.DstAddr > 2001:1::0) and " \
+                   "(ipv6.DstAddr < fc00::0 or ipv6.DstAddr > fe00::0) and " \
+                   "(ipv6.DstAddr < fe80::0 or ipv6.DstAddr > fec0::0) and " \
+                   "(ipv6.DstAddr < ff00::0 or ipv6.DstAddr > ffff::0)" \
+                   ")"
+#define DIVERT_NO_LOCALNETSv6_SRC "(" \
+                   "(ipv6.SrcAddr > ::1) and " \
+                   "(ipv6.SrcAddr < 2001::0 or ipv6.SrcAddr > 2001:1::0) and " \
+                   "(ipv6.SrcAddr < fc00::0 or ipv6.SrcAddr > fe00::0) and " \
+                   "(ipv6.SrcAddr < fe80::0 or ipv6.SrcAddr > fec0::0) and " \
+                   "(ipv6.SrcAddr < ff00::0 or ipv6.SrcAddr > ffff::0)" \
+                   ")"
+
+/* #IPID# is a template to find&replace */
+#define IPID_TEMPLATE "#IPID#"
+#define FILTER_STRING_TEMPLATE \
+        "(tcp and !impostor and !loopback and " \
+        "((inbound and (" \
+         "(" \
+          "(" \
+           "(ipv6 or (ip.Id >= 0x0 and ip.Id <= 0xF) " IPID_TEMPLATE \
+           ") and " \
+           "tcp.SrcPort == 80 and tcp.Ack" \
+          ") or " \
+          "((tcp.SrcPort == 80 or tcp.SrcPort == 443) and tcp.Ack and tcp.Syn)" \
+         ")" \
+         " and (" DIVERT_NO_LOCALNETSv4_SRC " or " DIVERT_NO_LOCALNETSv6_SRC "))) or " \
+        "(outbound and " \
+         "(tcp.DstPort == 80 or tcp.DstPort == 443) and tcp.Ack and " \
+         "(" DIVERT_NO_LOCALNETSv4_DST " or " DIVERT_NO_LOCALNETSv6_DST "))" \
+        "))"
+#define FILTER_PASSIVE_STRING_TEMPLATE "inbound and ip and tcp and " \
+        "!impostor and !loopback and " \
+        "((ip.Id <= 0xF and ip.Id >= 0x0) " IPID_TEMPLATE ") and " \
+        "(tcp.SrcPort == 443 or tcp.SrcPort == 80) and tcp.Rst and " \
+        DIVERT_NO_LOCALNETSv4_SRC
+
 #define SET_HTTP_FRAGMENT_SIZE_OPTION(fragment_size) do { \
    if (!http_fragment_size) { \
-        if (fragment_size <= 0 || fragment_size > 65535) { \
-            puts(fragment_size_message); \
-            exit(EXIT_FAILURE); \
-        } \
-        http_fragment_size = fragment_size; \
+        http_fragment_size = (unsigned int)fragment_size; \
    } \
    else if (http_fragment_size != (unsigned int)fragment_size) { \
        printf( \
@@ -56,13 +97,13 @@
 static int running_from_service = 0;
 static HANDLE filters[MAX_FILTERS];
 static int filter_num = 0;
-static const char *http10_redirect_302 = "HTTP/1.0 302 ";
-static const char *http11_redirect_302 = "HTTP/1.1 302 ";
-static const char *http_host_find = "\r\nHost: ";
-static const char *http_host_replace = "\r\nhoSt: ";
-static const char *http_useragent_find = "\r\nUser-Agent: ";
-static const char *location_http = "\r\nLocation: http://";
-static const char *connection_close = "\r\nConnection: close";
+static const char http10_redirect_302[] = "HTTP/1.0 302 ";
+static const char http11_redirect_302[] = "HTTP/1.1 302 ";
+static const char http_host_find[] = "\r\nHost: ";
+static const char http_host_replace[] = "\r\nhoSt: ";
+static const char http_useragent_find[] = "\r\nUser-Agent: ";
+static const char location_http[] = "\r\nLocation: http://";
+static const char connection_close[] = "\r\nConnection: close";
 static const char *http_methods[] = {
    "GET ",
    "HEAD ",
@@ -74,31 +115,30 @@ static const char *http_methods[] = {
 };

 static struct option long_options[] = {
-    {"port",      required_argument, 0,  'z' },
-    {"dns-addr",  required_argument, 0,  'd' },
-    {"dns-port",  required_argument, 0,  'g' },
-    {"dns-verb",  no_argument,       0,  'v' },
-    {"blacklist", required_argument, 0,  'b' },
-    {0,           0,                 0,   0  }
+    {"port",        required_argument, 0,  'z' },
+    {"dns-addr",    required_argument, 0,  'd' },
+    {"dns-port",    required_argument, 0,  'g' },
+    {"dnsv6-addr",  required_argument, 0,  '!' },
+    {"dnsv6-port",  required_argument, 0,  '@' },
+    {"dns-verb",    no_argument,       0,  'v' },
+    {"blacklist",   required_argument, 0,  'b' },
+    {"ip-id",       required_argument, 0,  'i' },
+    {"set-ttl",     required_argument, 0,  '$' },
+    {"wrong-chksum",no_argument,       0,  '%' },
+    {0,             0,                 0,   0  }
 };

 static char *filter_string = NULL;
-static char *filter_string_template = "(ip and tcp and "
-        "(inbound and (("
-         "((ip.Id == 0x0001 or ip.Id == 0x0000) and tcp.SrcPort == 80 and tcp.Ack) or "
-         "((tcp.SrcPort == 80 or tcp.SrcPort == 443) and tcp.Ack and tcp.Syn)"
-         ") and " DIVERT_NO_LOCALNETS_SRC ") or "
-        "(outbound and "
-         "(tcp.DstPort == 80 or tcp.DstPort == 443) and tcp.Ack and "
-         DIVERT_NO_LOCALNETS_DST ")"
-        "))";
+static char *filter_passive_string = NULL;

 static void add_filter_str(int proto, int port) {
-    const char *udp = " or (ip and udp and (udp.SrcPort == %d or udp.DstPort == %d))";
-    const char *tcp = " or (ip and tcp and (tcp.SrcPort == %d or tcp.DstPort == %d))";
+    const char *udp = " or (udp and !impostor and !loopback and " \
+                      "(udp.SrcPort == %d or udp.DstPort == %d))";
+    const char *tcp = " or (tcp and !impostor and !loopback and " \
+                      "(tcp.SrcPort == %d or tcp.DstPort == %d))";

    char *current_filter = filter_string;
-    int new_filter_size = strlen(current_filter) +
+    size_t new_filter_size = strlen(current_filter) +
            (proto == IPPROTO_UDP ? strlen(udp) : strlen(tcp)) + 16;
    char *new_filter = malloc(new_filter_size);

@@ -112,10 +152,40 @@ static void add_filter_str(int proto, int port) {
    free(current_filter);
 }

-static char* dumb_memmem(const char* haystack, int hlen, const char* needle, int nlen) {
+static void add_ip_id_str(int id) {
+    char *newstr;
+    const char *ipid = " or ip.Id == %d";
+    char *addfilter = malloc(strlen(ipid) + 16);
+
+    sprintf(addfilter, ipid, id);
+
+    newstr = repl_str(filter_string, IPID_TEMPLATE, addfilter);
+    free(filter_string);
+    filter_string = newstr;
+
+    newstr = repl_str(filter_passive_string, IPID_TEMPLATE, addfilter);
+    free(filter_passive_string);
+    filter_passive_string = newstr;
+}
+
+static void finalize_filter_strings() {
+    char *newstr;
+
+    newstr = repl_str(filter_string, IPID_TEMPLATE, "");
+    free(filter_string);
+    filter_string = newstr;
+
+    newstr = repl_str(filter_passive_string, IPID_TEMPLATE, "");
+    free(filter_passive_string);
+    filter_passive_string = newstr;
+}
+
+static char* dumb_memmem(const char* haystack, unsigned int hlen,
+                         const char* needle, size_t nlen)
+{
    // naive implementation
    if (nlen > hlen) return NULL;
-    int i;
+    size_t i;
    for (i=0; i<hlen-nlen+1; i++) {
        if (memcmp(haystack+i,needle,nlen)==0) {
            return (char*)(haystack+i);
@@ -124,17 +194,56 @@ static char* dumb_memmem(const char* haystack, int hlen, const char* needle, int
    return NULL;
 }

+unsigned short int atousi(const char *str, const char *msg) {
+    long unsigned int res = strtoul(str, NULL, 10u);
+    enum {
+        limitValue=0xFFFFu
+    };
+
+    if(res > limitValue) {
+        puts(msg);
+        exit(EXIT_FAILURE);
+    }
+    return (unsigned short int)res;
+}
+
+BYTE atoub(const char *str, const char *msg) {
+    long unsigned int res = strtoul(str, NULL, 10u);
+    enum {
+        limitValue=0xFFu
+    };
+
+    if(res > limitValue) {
+        puts(msg);
+        exit(EXIT_FAILURE);
+    }
+    return (BYTE)res;
+}
+
+
 static HANDLE init(char *filter, UINT64 flags) {
    LPTSTR errormessage = NULL;
+    DWORD errorcode = 0;
    filter = WinDivertOpen(filter, WINDIVERT_LAYER_NETWORK, 0, flags);
    if (filter != INVALID_HANDLE_VALUE)
        return filter;
+    errorcode = GetLastError();
    FormatMessage(FORMAT_MESSAGE_ALLOCATE_BUFFER | FORMAT_MESSAGE_FROM_SYSTEM |
                  FORMAT_MESSAGE_IGNORE_INSERTS,
-                  NULL, GetLastError(), MAKELANGID(LANG_ENGLISH, SUBLANG_DEFAULT),
+                  NULL, errorcode, MAKELANGID(LANG_ENGLISH, SUBLANG_DEFAULT),
                  (LPTSTR)&errormessage, 0, NULL);
-    printf("%s", errormessage);
-    free(errormessage);
+    printf("Error opening filter: %s", errormessage);
+    LocalFree(errormessage);
+    if (errorcode == 577)
+        printf("Windows Server 2016 systems must have secure boot disabled to be "
+               "able to load WinDivert driver.\n"
+               "Windows 7 systems must be up-to-date or at least have KB3033929 installed.\n"
+               "https://www.microsoft.com/en-us/download/details.aspx?id=46078\n\n"
+               "WARNING! If you see this error on Windows 7, it means your system is horribly "
+               "outdated and SHOULD NOT BE USED TO ACCESS THE INTERNET!\n"
+               "Most probably, you don't have security patches installed and anyone in you LAN or "
+               "public Wi-Fi network can get full access to your computer (MS17-010 and others).\n"
+               "You should install updates IMMEDIATELY.\n");
    return NULL;
 }

@@ -157,39 +266,39 @@ static void sigint_handler(int sig __attribute__((unused))) {
    exit(EXIT_SUCCESS);
 }

-static void mix_case(char *pktdata, int pktlen) {
-    int i;
+static void mix_case(char *pktdata, unsigned int pktlen) {
+    unsigned int i;

    if (pktlen <= 0) return;
    for (i = 0; i < pktlen; i++) {
        if (i % 2) {
-            pktdata[i] = toupper(pktdata[i]);
+            pktdata[i] = (char) toupper(pktdata[i]);
        }
    }
 }

-static int is_passivedpi_redirect(const char *pktdata, int pktlen) {
+static int is_passivedpi_redirect(const char *pktdata, unsigned int pktlen) {
    /* First check if this is HTTP 302 redirect */
-    if (memcmp(pktdata, http11_redirect_302, strlen(http11_redirect_302)) == 0 ||
-        memcmp(pktdata, http10_redirect_302, strlen(http10_redirect_302)) == 0)
+    if (memcmp(pktdata, http11_redirect_302, sizeof(http11_redirect_302)-1) == 0 ||
+        memcmp(pktdata, http10_redirect_302, sizeof(http10_redirect_302)-1) == 0)
    {
        /* Then check if this is a redirect to new http site with Connection: close */
-        if (dumb_memmem(pktdata, pktlen, location_http, strlen(location_http)) &&
-            dumb_memmem(pktdata, pktlen, connection_close, strlen(connection_close))) {
+        if (dumb_memmem(pktdata, pktlen, location_http, sizeof(location_http)-1) &&
+            dumb_memmem(pktdata, pktlen, connection_close, sizeof(connection_close)-1)) {
            return TRUE;
        }
    }
    return FALSE;
 }

-static int find_header_and_get_info(const char *pktdata, int pktlen,
+static int find_header_and_get_info(const char *pktdata, unsigned int pktlen,
                const char *hdrname,
                char **hdrnameaddr,
-                char **hdrvalueaddr, int *hdrvaluelen) {
+                char **hdrvalueaddr, unsigned int *hdrvaluelen) {
    char *data_addr_rn;
    char *hdr_begin;

-    *hdrvaluelen = 0;
+    *hdrvaluelen = 0u;
    *hdrnameaddr = NULL;
    *hdrvalueaddr = NULL;

@@ -209,20 +318,20 @@ static int find_header_and_get_info(const char *pktdata, int pktlen,
                        "\r\n", 2);
    if (data_addr_rn) {
        *hdrvaluelen = (PVOID)data_addr_rn - (PVOID)*hdrvalueaddr;
-        if (*hdrvaluelen > 0 && *hdrvaluelen <= 512)
+        if (*hdrvaluelen > 0u && *hdrvaluelen <= 512u)
            return TRUE;
    }
    return FALSE;
 }

-static inline void change_window_size(const PWINDIVERT_TCPHDR ppTcpHdr, int size) {
-    if (size >= 1 && size <= 65535) {
-        ppTcpHdr->Window = htons(size);
+static inline void change_window_size(const PWINDIVERT_TCPHDR ppTcpHdr, unsigned int size) {
+    if (size >= 1 && size <= 0xFFFFu) {
+        ppTcpHdr->Window = htons((u_short)size);
    }
 }

 /* HTTP method end without trailing space */
-static PVOID find_http_method_end(const char *pkt, int http_frag, int *is_fragmented) {
+static PVOID find_http_method_end(const char *pkt, unsigned int http_frag, int *is_fragmented) {
    unsigned int i;
    for (i = 0; i<(sizeof(http_methods) / sizeof(*http_methods)); i++) {
        if (memcmp(pkt, http_methods[i], strlen(http_methods[i])) == 0) {
@@ -245,10 +354,14 @@ static PVOID find_http_method_end(const char *pkt, int http_frag, int *is_fragme
 }

 int main(int argc, char *argv[]) {
-    static const char *fragment_size_message =
-                "Fragment size should be in range [0 - 65535]\n";
+    static enum packet_type_e {
+        unknown,
+        ipv4_tcp, ipv4_tcp_data, ipv4_udp_data,
+        ipv6_tcp, ipv6_tcp_data, ipv6_udp_data
+    } packet_type;
    int i, should_reinject, should_recalc_checksum = 0;
    int opt;
+    int packet_v4, packet_v6;
    HANDLE w_filter = NULL;
    WINDIVERT_ADDRESS addr;
    char packet[MAX_PACKET_SIZE];
@@ -256,6 +369,7 @@ int main(int argc, char *argv[]) {
    UINT packetLen;
    UINT packet_dataLen;
    PWINDIVERT_IPHDR ppIpHdr;
+    PWINDIVERT_IPV6HDR ppIpV6Hdr;
    PWINDIVERT_TCPHDR ppTcpHdr;
    PWINDIVERT_UDPHDR ppUdpHdr;
    conntrack_info_t dns_conn_info;
@@ -266,37 +380,61 @@ int main(int argc, char *argv[]) {
        do_fragment_https = 0, do_host = 0,
        do_host_removespace = 0, do_additional_space = 0,
        do_http_allports = 0,
-        do_host_mixedcase = 0, do_dns_redirect = 0,
-        do_dns_verb = 0, do_blacklist = 0;
-    unsigned int http_fragment_size = 2;
-    unsigned int https_fragment_size = 2;
-    uint32_t dns_addr = 0;
-    uint16_t dns_port = htons(53);
+        do_host_mixedcase = 0,
+        do_dnsv4_redirect = 0, do_dnsv6_redirect = 0,
+        do_dns_verb = 0, do_blacklist = 0,
+        do_wrong_chksum = 0;
+    unsigned int http_fragment_size = 0;
+    unsigned int https_fragment_size = 0;
+    BYTE ttl_of_fake_packet = 0;
+    uint32_t dnsv4_addr = 0;
+    struct in6_addr dnsv6_addr = {0};
+    struct in6_addr dns_temp_addr = {0};
+    uint16_t dnsv4_port = htons(53);
+    uint16_t dnsv6_port = htons(53);
    char *host_addr, *useragent_addr, *method_addr;
-    int host_len, useragent_len;
+    unsigned int host_len, useragent_len;
    int http_req_fragmented;

    char *hdr_name_addr = NULL, *hdr_value_addr = NULL;
-    int hdr_value_len;
+    unsigned int hdr_value_len;

-    if (!running_from_service && service_register(argc, argv)) {
-        /* We've been called as a service. Register service
-         * and exit this thread. main() would be called from
-         * service.c next time.
-         */
+    // Make sure to search DLLs only in safe path, not in current working dir.
+    SetDllDirectory("");
+    SetSearchPathMode(BASE_SEARCH_PATH_ENABLE_SAFE_SEARCHMODE | BASE_SEARCH_PATH_PERMANENT);
+
+    if (!running_from_service) {
        running_from_service = 1;
-        return 0;
+        if (service_register(argc, argv)) {
+            /* We've been called as a service. Register service
+             * and exit this thread. main() would be called from
+             * service.c next time.
+             *
+             * Note that if service_register() succeedes it does
+             * not return until the service is stopped.
+             * That is why we should set running_from_service
+             * before calling service_register and unset it
+             * afterwards.
+             */
+            return 0;
+        }
+        running_from_service = 0;
    }

-    if (filter_string == NULL) {
-        filter_string = malloc(strlen(filter_string_template) + 1);
-        strcpy(filter_string, filter_string_template);
-    }
+    if (filter_string == NULL)
+        filter_string = strdup(FILTER_STRING_TEMPLATE);
+    if (filter_passive_string == NULL)
+        filter_passive_string = strdup(FILTER_PASSIVE_STRING_TEMPLATE);

-    printf("GoodbyeDPI: Passive DPI blocker and Active DPI circumvention utility\n");
+    printf(
+        "GoodbyeDPI " GOODBYEDPI_VERSION
+        ": Passive DPI blocker and Active DPI circumvention utility\n"
+        "https://github.com/ValdikSS/GoodbyeDPI\n\n"
+    );

    if (argc == 1) {
        /* enable mode -1 by default */
+        http_fragment_size = https_fragment_size = 2;
        do_passivedpi = do_host = do_host_removespace \
                = do_fragment_http = do_fragment_https \
                = do_fragment_http_persistent \
@@ -316,12 +454,12 @@ int main(int argc, char *argv[]) {
                = do_fragment_http = do_fragment_https \
                = do_fragment_http_persistent \
                = do_fragment_http_persistent_nowait = 1;
-                https_fragment_size = 40;
+                https_fragment_size = 40u;
                break;
            case '3':
                do_passivedpi = do_host = do_host_removespace \
                = do_fragment_https = 1;
-                https_fragment_size = 40;
+                https_fragment_size = 40u;
                break;
            case '4':
                do_passivedpi = do_host = do_host_removespace = 1;
@@ -344,22 +482,18 @@ int main(int argc, char *argv[]) {
                break;
            case 'f':
                do_fragment_http = 1;
-                SET_HTTP_FRAGMENT_SIZE_OPTION(atoi(optarg));
+                SET_HTTP_FRAGMENT_SIZE_OPTION(atousi(optarg, "Fragment size should be in range [0 - 0xFFFF]\n"));
                break;
            case 'k':
                do_fragment_http_persistent = 1;
-                SET_HTTP_FRAGMENT_SIZE_OPTION(atoi(optarg));
+                SET_HTTP_FRAGMENT_SIZE_OPTION(atousi(optarg, "Fragment size should be in range [0 - 0xFFFF]\n"));
                break;
            case 'n':
                do_fragment_http_persistent_nowait = 1;
                break;
            case 'e':
                do_fragment_https = 1;
-                https_fragment_size = atoi(optarg);
-                if (https_fragment_size <= 0 || https_fragment_size > 65535) {
-                    puts(fragment_size_message);
-                    exit(EXIT_FAILURE);
-                }
+                https_fragment_size = atousi(optarg, "Fragment size should be in range [0 - 65535]\n");
                break;
            case 'w':
                do_http_allports = 1;
@@ -375,34 +509,69 @@ int main(int argc, char *argv[]) {
                    add_filter_str(IPPROTO_TCP, i);
                i = 0;
                break;
+            case 'i':
+                /* i is used as a temporary variable here */
+                i = atousi(optarg, "IP ID parameter error!\n");
+                add_ip_id_str(i);
+                i = 0;
+                break;
            case 'd':
-                if (!do_dns_redirect) {
-                    do_dns_redirect = 1;
-                    dns_addr = inet_addr(optarg);
-                    if (!dns_addr) {
-                        printf("DNS address parameter error!\n");
+                if ((inet_pton(AF_INET, optarg, dns_temp_addr.s6_addr) == 1) &&
+                    !do_dnsv4_redirect)
+                {
+                    do_dnsv4_redirect = 1;
+                    if (inet_pton(AF_INET, optarg, &dnsv4_addr) != 1) {
+                        puts("DNS address parameter error!");
                        exit(EXIT_FAILURE);
                    }
                    add_filter_str(IPPROTO_UDP, 53);
                    flush_dns_cache();
+                    break;
                }
+                puts("DNS address parameter error!");
+                exit(EXIT_FAILURE);
+                break;
+            case '!':
+                if ((inet_pton(AF_INET6, optarg, dns_temp_addr.s6_addr) == 1) &&
+                    !do_dnsv6_redirect)
+                {
+                    do_dnsv6_redirect = 1;
+                    if (inet_pton(AF_INET6, optarg, dnsv6_addr.s6_addr) != 1) {
+                        puts("DNS address parameter error!");
+                        exit(EXIT_FAILURE);
+                    }
+                    add_filter_str(IPPROTO_UDP, 53);
+                    flush_dns_cache();
+                    break;
+                }
+                puts("DNS address parameter error!");
+                exit(EXIT_FAILURE);
                break;
            case 'g':
-                if (!do_dns_redirect) {
-                    printf("--dns-port should be used with --dns-addr!\n"
+                if (!do_dnsv4_redirect) {
+                    puts("--dns-port should be used with --dns-addr!\n"
                        "Make sure you use --dns-addr and pass it before "
-                        "--dns-port\n");
+                        "--dns-port");
                    exit(EXIT_FAILURE);
                }
-                dns_port = atoi(optarg);
-                if (atoi(optarg) <= 0 || atoi(optarg) > 65535) {
-                    printf("DNS port parameter error!\n");
+                dnsv4_port = atousi(optarg, "DNS port parameter error!");
+                if (dnsv4_port != 53) {
+                    add_filter_str(IPPROTO_UDP, dnsv4_port);
+                }
+                dnsv4_port = htons(dnsv4_port);
+                break;
+            case '@':
+                if (!do_dnsv6_redirect) {
+                    puts("--dnsv6-port should be used with --dnsv6-addr!\n"
+                        "Make sure you use --dnsv6-addr and pass it before "
+                        "--dnsv6-port");
                    exit(EXIT_FAILURE);
                }
-                if (dns_port != 53) {
-                    add_filter_str(IPPROTO_UDP, dns_port);
+                dnsv6_port = atousi(optarg, "DNS port parameter error!");
+                if (dnsv6_port != 53) {
+                    add_filter_str(IPPROTO_UDP, dnsv6_port);
                }
-                dns_port = ntohs(dns_port);
+                dnsv6_port = htons(dnsv6_port);
                break;
            case 'v':
                do_dns_verb = 1;
@@ -414,8 +583,14 @@ int main(int argc, char *argv[]) {
                    exit(EXIT_FAILURE);
                }
                break;
+            case '$':
+                ttl_of_fake_packet = atoub(optarg, "Set TTL parameter error!");
+                break;
+            case '%':
+                do_wrong_chksum = 1;
+                break;
            default:
-                printf("Usage: goodbyedpi.exe [OPTION...]\n"
+                puts("Usage: goodbyedpi.exe [OPTION...]\n"
                " -p          block passive DPI\n"
                " -r          replace Host with hoSt\n"
                " -s          remove space between host header and its value\n"
@@ -426,30 +601,46 @@ int main(int argc, char *argv[]) {
                " -n          do not wait for first segment ACK when -k is enabled\n"
                " -e [value]  set HTTPS fragmentation to value\n"
                " -w          try to find and parse HTTP traffic on all processed ports (not only on port 80)\n"
-                " --port      [value]    additional TCP port to perform fragmentation on (and HTTP tricks with -w)\n"
-                " --dns-addr  [value]    redirect UDP DNS requests to the supplied IP address (experimental)\n"
-                " --dns-port  [value]    redirect UDP DNS requests to the supplied port (53 by default)\n"
-                " --dns-verb             print verbose DNS redirection messages\n"
-                " --blacklist [txtfile]  perform HTTP tricks only to host names and subdomains from\n"
-                "                        supplied text file. This option can be supplied multiple times.\n"
+                " --port        [value]    additional TCP port to perform fragmentation on (and HTTP tricks with -w)\n"
+                " --ip-id       [value]    handle additional IP ID (decimal, drop redirects and TCP RSTs with this ID).\n"
+                " --dns-addr    [value]    redirect UDPv4 DNS requests to the supplied IPv4 address (experimental)\n"
+                " --dns-port    [value]    redirect UDPv4 DNS requests to the supplied port (53 by default)\n"
+                " --dnsv6-addr  [value]    redirect UDPv6 DNS requests to the supplied IPv6 address (experimental)\n"
+                " --dnsv6-port  [value]    redirect UDPv6 DNS requests to the supplied port (53 by default)\n"
+                " --dns-verb               print verbose DNS redirection messages\n"
+                " --blacklist   [txtfile]  perform HTTP tricks only to host names and subdomains from\n"
+                "                          supplied text file. This option can be supplied multiple times.\n"
+                " --set-ttl     [value]    activate Fake Request Mode and send it with supplied TTL value.\n"
+                "                          DANGEROUS! May break websites in unexpected ways. Use with care.\n"
+                "                          Could be combined with --wrong-chksum.\n"
+                " --wrong-chksum           activate Fake Request Mode and send it with incorrect TCP checksum.\n"
+                "                          May not work in a VM or with some routers, but is safer than set-ttl.\n"
+                "                          Could be combined with --set-ttl\n."
                "\n"
                " -1          -p -r -s -f 2 -k 2 -n -e 2 (most compatible mode, default)\n"
                " -2          -p -r -s -f 2 -k 2 -n -e 40 (better speed for HTTPS yet still compatible)\n"
                " -3          -p -r -s -e 40 (better speed for HTTP and HTTPS)\n"
-                " -4          -p -r -s (best speed)\n");
+                " -4          -p -r -s (best speed)");
                exit(EXIT_FAILURE);
        }
    }

-    printf("Block passive: %d, Fragment HTTP: %d, Fragment persistent HTTP: %d, "
-           "Fragment HTTPS: %d, "
-           "hoSt: %d, Host no space: %d, Additional space: %d, Mix Host: %d, "
-           "HTTP AllPorts: %d, HTTP Persistent Nowait: %d, DNS redirect: %d\n",
+    if (!http_fragment_size)
+        http_fragment_size = 2;
+    if (!https_fragment_size)
+        https_fragment_size = 2;
+
+    printf("Block passive: %d\nFragment HTTP: %d\nFragment persistent HTTP: %d\n"
+           "Fragment HTTPS: %d\nhoSt: %d\nHost no space: %d\nAdditional space: %d\n"
+           "Mix Host: %d\nHTTP AllPorts: %d\nHTTP Persistent Nowait: %d\n"
+           "DNS redirect: %d\nDNSv6 redirect: %d\n"
+           "Fake requests, TTL: %hu\nFake requests, wrong checksum: %d\n",
           do_passivedpi, (do_fragment_http ? http_fragment_size : 0),
           (do_fragment_http_persistent ? http_fragment_size : 0),
           (do_fragment_https ? https_fragment_size : 0),
           do_host, do_host_removespace, do_additional_space, do_host_mixedcase,
-           do_http_allports, do_fragment_http_persistent_nowait, do_dns_redirect
+           do_http_allports, do_fragment_http_persistent_nowait, do_dnsv4_redirect,
+           do_dnsv6_redirect, ttl_of_fake_packet, do_wrong_chksum
          );

    if (do_fragment_http && http_fragment_size > 2) {
@@ -459,21 +650,21 @@ int main(int argc, char *argv[]) {
    }

    printf("\nOpening filter\n");
+    finalize_filter_strings();
    filter_num = 0;

    if (do_passivedpi) {
-        /* IPv4 filter for inbound RST packets with ID = 0 or 1 */
+        /* IPv4 only filter for inbound RST packets with ID [0x0; 0xF] */
        filters[filter_num] = init(
-            "inbound and ip and tcp and "
-            "(ip.Id == 0x0001 or ip.Id == 0x0000) and "
-            "(tcp.SrcPort == 443 or tcp.SrcPort == 80) and tcp.Rst and "
-            DIVERT_NO_LOCALNETS_SRC,
+            filter_passive_string,
            WINDIVERT_FLAG_DROP);
+        if (filters[filter_num] == NULL)
+            die();
        filter_num++;
    }

    /* 
-     * IPv4 filter for inbound HTTP redirection packets and
+     * IPv4 & IPv6 filter for inbound HTTP redirection packets and
     * active DPI circumvention
     */
    filters[filter_num] = init(filter_string, 0);
@@ -491,13 +682,53 @@ int main(int argc, char *argv[]) {

    while (1) {
        if (WinDivertRecv(w_filter, packet, sizeof(packet), &addr, &packetLen)) {
-            //printf("Got %s packet, len=%d!\n", addr.Direction ? "inbound" : "outbound",
-            //       packetLen);
+            debug("Got %s packet, len=%d!\n", addr.Direction ? "inbound" : "outbound",
+                   packetLen);
            should_reinject = 1;
            should_recalc_checksum = 0;

-            if (WinDivertHelperParsePacket(packet, packetLen, &ppIpHdr,
-                NULL, NULL, NULL, &ppTcpHdr, NULL, &packet_data, &packet_dataLen)) {
+            ppIpHdr = (PWINDIVERT_IPHDR)NULL;
+            ppIpV6Hdr = (PWINDIVERT_IPV6HDR)NULL;
+            ppTcpHdr = (PWINDIVERT_TCPHDR)NULL;
+            ppUdpHdr = (PWINDIVERT_UDPHDR)NULL;
+            packet_v4 = packet_v6 = 0;
+            packet_type = unknown;
+
+            // Parse network packet and set it's type
+            if ((packet_v4 = WinDivertHelperParsePacket(packet, packetLen, &ppIpHdr,
+                NULL, NULL, NULL, &ppTcpHdr, NULL, &packet_data, &packet_dataLen)))
+            {
+                packet_type = ipv4_tcp_data;
+            }
+            else if ((packet_v6 = WinDivertHelperParsePacket(packet, packetLen, NULL,
+                &ppIpV6Hdr, NULL, NULL, &ppTcpHdr, NULL, &packet_data, &packet_dataLen)))
+            {
+                packet_type = ipv6_tcp_data;
+            }
+            else if ((packet_v4 = WinDivertHelperParsePacket(packet, packetLen, &ppIpHdr,
+                NULL, NULL, NULL, &ppTcpHdr, NULL, NULL, NULL)))
+            {
+                packet_type = ipv4_tcp;
+            }
+            else if ((packet_v6 = WinDivertHelperParsePacket(packet, packetLen, NULL,
+                &ppIpV6Hdr, NULL, NULL, &ppTcpHdr, NULL, NULL, NULL)))
+            {
+                packet_type = ipv6_tcp;
+            }
+            else if ((packet_v4 = WinDivertHelperParsePacket(packet, packetLen, &ppIpHdr,
+                NULL, NULL, NULL, NULL, &ppUdpHdr, &packet_data, &packet_dataLen)))
+            {
+                packet_type = ipv4_udp_data;
+            }
+            else if ((packet_v6 = WinDivertHelperParsePacket(packet, packetLen, NULL,
+                &ppIpV6Hdr, NULL, NULL, NULL, &ppUdpHdr, &packet_data, &packet_dataLen)))
+            {
+                packet_type = ipv6_udp_data;
+            }
+
+            debug("packet_type: %d, packet_v4: %d, packet_v6: %d\n", packet_type, packet_v4, packet_v6);
+
+            if (packet_type == ipv4_tcp_data || packet_type == ipv6_tcp_data) {
                //printf("Got parsed packet, len=%d!\n", packet_dataLen);
                /* Got a TCP packet WITH DATA */

@@ -507,8 +738,35 @@ int main(int argc, char *argv[]) {

                    /* Drop packets from filter with HTTP 30x Redirect */
                    if (do_passivedpi && is_passivedpi_redirect(packet_data, packet_dataLen)) {
-                        //printf("Dropping HTTP Redirect packet!\n");
-                        should_reinject = 0;
+                        if (packet_v4) {
+                            //printf("Dropping HTTP Redirect packet!\n");
+                            should_reinject = 0;
+                        }
+                        else if (packet_v6 && WINDIVERT_IPV6HDR_GET_FLOWLABEL(ppIpV6Hdr) == 0x0) {
+                                /* Contrary to IPv4 where we get only packets with IP ID 0x0-0xF,
+                                 * for IPv6 we got all the incoming data packets since we can't
+                                 * filter them in a driver.
+                                 *
+                                 * Handle only IPv6 Flow Label == 0x0 for now
+                                 */
+                                //printf("Dropping HTTP Redirect packet!\n");
+                                should_reinject = 0;
+                        }
+                    }
+                }
+                /* Handle OUTBOUND packet on port 443, search for something that resembles
+                 * TLS handshake, send fake request.
+                 */
+                else if (addr.Direction == WINDIVERT_DIRECTION_OUTBOUND &&
+                        ((do_fragment_https ? packet_dataLen == https_fragment_size : 0) ||
+                         packet_dataLen > 16) &&
+                         ppTcpHdr->DstPort != htons(80) &&
+                         (ttl_of_fake_packet || do_wrong_chksum)
+                        )
+                {
+                    if (packet_dataLen >=2 && memcmp(packet_data, "\x16\x03", 2) == 0) {
+                        send_fake_https_request(w_filter, &addr, packet, packetLen, packet_v6,
+                                                ttl_of_fake_packet, do_wrong_chksum);
                    }
                }
                /* Handle OUTBOUND packet on port 80, search for Host header */
@@ -516,7 +774,7 @@ int main(int argc, char *argv[]) {
                        packet_dataLen > 16 &&
                        (do_http_allports ? 1 : (ppTcpHdr->DstPort == htons(80))) &&
                        find_http_method_end(packet_data,
-                                             (do_fragment_http ? http_fragment_size : 0),
+                                             (do_fragment_http ? http_fragment_size : 0u),
                                             &http_req_fragmented) &&
                        (do_host || do_host_removespace ||
                        do_host_mixedcase || do_fragment_http_persistent))
@@ -531,6 +789,11 @@ int main(int argc, char *argv[]) {
                        host_addr = hdr_value_addr;
                        host_len = hdr_value_len;

+                        if (ttl_of_fake_packet || do_wrong_chksum)
+                            send_fake_http_request(w_filter, &addr, packet, packetLen, packet_v6,
+                                                   ttl_of_fake_packet, do_wrong_chksum);
+
+
                        /*
                         * Handle new HTTP request in new
                         * connection (when Window Size modification disabled)
@@ -544,25 +807,39 @@ int main(int argc, char *argv[]) {
                         * but it's better to send it anyway since it eliminates one RTT.
                         */
                        if (do_fragment_http_persistent && !http_req_fragmented &&
-                            (packet_dataLen > http_fragment_size)
-                        ) {
-                            ppIpHdr->Length = htons(
-                                ntohs(ppIpHdr->Length) -
-                                packet_dataLen + http_fragment_size
-                            );
+                            (packet_dataLen > http_fragment_size))
+                        {
+                            if (packet_v4)
+                                ppIpHdr->Length = htons(
+                                    ntohs(ppIpHdr->Length) -
+                                    packet_dataLen + http_fragment_size
+                                );
+                            else if (packet_v6)
+                                ppIpV6Hdr->Length = htons(
+                                    ntohs(ppIpV6Hdr->Length) -
+                                    packet_dataLen + http_fragment_size
+                                );
+
                            WinDivertHelperCalcChecksums(
-                                packet, packetLen - packet_dataLen + http_fragment_size, 0
+                                packet, packetLen - packet_dataLen + http_fragment_size, &addr, 0
                            );
                            WinDivertSend(
                                w_filter, packet,
                                packetLen - packet_dataLen + http_fragment_size,
                                &addr, NULL
                            );
+
                            if (do_fragment_http_persistent_nowait) {
-                                ppIpHdr->Length = htons(
-                                    ntohs(ppIpHdr->Length) -
-                                    http_fragment_size + packet_dataLen - http_fragment_size
-                                );
+                                if (packet_v4)
+                                    ppIpHdr->Length = htons(
+                                        ntohs(ppIpHdr->Length) -
+                                        http_fragment_size + packet_dataLen - http_fragment_size
+                                    );
+                                else if (packet_v6)
+                                    ppIpV6Hdr->Length = htons(
+                                        ntohs(ppIpV6Hdr->Length) -
+                                        http_fragment_size + packet_dataLen - http_fragment_size
+                                    );
                                memmove(packet_data,
                                        packet_data + http_fragment_size,
                                        packet_dataLen);
@@ -659,8 +936,7 @@ int main(int argc, char *argv[]) {
            } /* Handle TCP packet with data */

            /* Else if we got TCP packet without data */
-            else if (WinDivertHelperParsePacket(packet, packetLen, &ppIpHdr,
-                NULL, NULL, NULL, &ppTcpHdr, NULL, NULL, NULL)) {
+            else if (packet_type == ipv4_tcp || packet_type == ipv6_tcp) {
                /* If we got INBOUND SYN+ACK packet */
                if (addr.Direction == WINDIVERT_DIRECTION_INBOUND &&
                    ppTcpHdr->Syn == 1 && ppTcpHdr->Ack == 1) {
@@ -681,17 +957,24 @@ int main(int argc, char *argv[]) {
            }

            /* Else if we got UDP packet with data */
-            else if (do_dns_redirect && WinDivertHelperParsePacket(packet, packetLen, &ppIpHdr,
-                NULL, NULL, NULL, NULL, &ppUdpHdr, &packet_data, &packet_dataLen)) {
-
+            else if ((do_dnsv4_redirect && (packet_type == ipv4_udp_data)) ||
+                     (do_dnsv6_redirect && (packet_type == ipv6_udp_data)))
+            {
                if (addr.Direction == WINDIVERT_DIRECTION_INBOUND) {
-                    if (dns_handle_incoming(ppIpHdr->DstAddr, ppUdpHdr->DstPort,
+                    if ((packet_v4 && dns_handle_incoming(&ppIpHdr->DstAddr, ppUdpHdr->DstPort,
                                        packet_data, packet_dataLen,
-                                        &dns_conn_info))
+                                        &dns_conn_info, 0))
+                        ||
+                        (packet_v6 && dns_handle_incoming(ppIpV6Hdr->DstAddr, ppUdpHdr->DstPort,
+                                        packet_data, packet_dataLen,
+                                        &dns_conn_info, 1)))
                    {
                        /* Changing source IP and port to the values
                         * from DNS conntrack */
-                        ppIpHdr->SrcAddr = dns_conn_info.dstip;
+                        if (packet_v4)
+                            ppIpHdr->SrcAddr = dns_conn_info.dstip[0];
+                        else if (packet_v6)
+                            ipv6_copy_addr(ppIpV6Hdr->SrcAddr, dns_conn_info.dstip);
                        ppUdpHdr->DstPort = dns_conn_info.srcport;
                        ppUdpHdr->SrcPort = dns_conn_info.dstport;
                        should_recalc_checksum = 1;
@@ -708,14 +991,24 @@ int main(int argc, char *argv[]) {
                }

                else if (addr.Direction == WINDIVERT_DIRECTION_OUTBOUND) {
-                    if (dns_handle_outgoing(ppIpHdr->SrcAddr, ppUdpHdr->SrcPort,
-                                        ppIpHdr->DstAddr, ppUdpHdr->DstPort,
-                                        packet_data, packet_dataLen))
+                    if ((packet_v4 && dns_handle_outgoing(&ppIpHdr->SrcAddr, ppUdpHdr->SrcPort,
+                                        &ppIpHdr->DstAddr, ppUdpHdr->DstPort,
+                                        packet_data, packet_dataLen, 0))
+                        ||
+                        (packet_v6 && dns_handle_outgoing(ppIpV6Hdr->SrcAddr, ppUdpHdr->SrcPort,
+                                        ppIpV6Hdr->DstAddr, ppUdpHdr->DstPort,
+                                        packet_data, packet_dataLen, 1)))
                    {
                        /* Changing destination IP and port to the values
                         * from configuration */
-                        ppIpHdr->DstAddr = dns_addr;
-                        ppUdpHdr->DstPort = dns_port;
+                        if (packet_v4) {
+                            ppIpHdr->DstAddr = dnsv4_addr;
+                            ppUdpHdr->DstPort = dnsv4_port;
+                        }
+                        else if (packet_v6) {
+                            ipv6_copy_addr(ppIpV6Hdr->DstAddr, (uint32_t*)dnsv6_addr.s6_addr);
+                            ppUdpHdr->DstPort = dnsv6_port;
+                        }
                        should_recalc_checksum = 1;
                    }
                    else {
@@ -733,11 +1026,7 @@ int main(int argc, char *argv[]) {
            if (should_reinject) {
                //printf("Re-injecting!\n");
                if (should_recalc_checksum) {
-                    WinDivertHelperCalcChecksums(packet, packetLen, 0);
-                }
-                else {
-                    WinDivertHelperCalcChecksums(packet, packetLen,
-                                                 WINDIVERT_HELPER_NO_REPLACE);
+                    WinDivertHelperCalcChecksums(packet, packetLen, &addr, NULL);
                }
                WinDivertSend(w_filter, packet, packetLen, &addr, NULL);
            }
--- a/src/goodbyedpi.exe.manifest
+++ b/src/goodbyedpi.exe.manifest
@@ -1,7 +1,7 @@
 <?xml version="1.0" encoding="UTF-8" standalone="yes"?>
 <assembly xmlns="urn:schemas-microsoft-com:asm.v1" manifestVersion="1.0">
-    <assemblyIdentity version="1.0.0.0" processorArchitecture="X86" name="GoodbyeDPI" type="win32"/> 
-    <description>Divert</description> 
+    <assemblyIdentity version="1.0.0.0" processorArchitecture="X86" name="GoodbyeDPI" type="win32"/>
+    <description>GoodbyeDPI</description>
    <trustInfo xmlns="urn:schemas-microsoft-com:asm.v2">
        <security>
            <requestedPrivileges>
@@ -9,4 +9,4 @@
            </requestedPrivileges>
        </security>
    </trustInfo>
-</assembly> 
+</assembly>
--- a/src/goodbyedpi.h
+++ b/src/goodbyedpi.h
@@ -1,4 +1,5 @@
 #define HOST_MAXLEN 253
+#define MAX_PACKET_SIZE 9016

 #ifndef DEBUG
 #define debug(...) do {} while (0)
--- a/src/icon.ico
+++ b/src/icon.ico
--- a/src/service.c
+++ b/src/service.c
@@ -7,11 +7,12 @@

 static SERVICE_STATUS ServiceStatus;
 static SERVICE_STATUS_HANDLE hStatus;
-static int service_argc;
-static char **service_argv;
+static int service_argc = 0;
+static char **service_argv = NULL;

 int service_register(int argc, char *argv[])
 {
+    int i, ret;
    SERVICE_TABLE_ENTRY ServiceTable[] = {
        {SERVICE_NAME, (LPSERVICE_MAIN_FUNCTION)service_main},
        {NULL, NULL}
@@ -21,13 +22,30 @@ int service_register(int argc, char *argv[])
     * arguments, which are passed from "start" command, not
     * from the program command line.
     * We don't need this behaviour.
+     *
+     * Note that if StartServiceCtrlDispatcher() succeedes
+     * it does not return until the service is stopped,
+     * so we should copy all arguments first and then
+     * handle the failure.
     */
-    service_argc = argc;
-    service_argv = malloc(sizeof(void*) * argc);
-    for (int i = 0; i < argc; i++) {
-        service_argv[i] = strdup(argv[i]);
+    if (!service_argc && !service_argv) {
+        service_argc = argc;
+        service_argv = malloc(sizeof(void*) * argc);
+        for (i = 0; i < argc; i++) {
+            service_argv[i] = strdup(argv[i]);
+        }
    }
-    return StartServiceCtrlDispatcher(ServiceTable);
+
+    ret = StartServiceCtrlDispatcher(ServiceTable);
+
+    if (service_argc && service_argv) {
+        for (i = 0; i < service_argc; i++) {
+            free(service_argv[i]);
+        }
+        free(service_argv);
+    }
+
+    return ret;
 }

 void service_main(int argc __attribute__((unused)),
@@ -53,14 +71,9 @@ void service_main(int argc __attribute__((unused)),
    SetServiceStatus(hStatus, &ServiceStatus);

    // Calling main with saved argc & argv
-    main(service_argc, service_argv);
-
-    if (ServiceStatus.dwCurrentState != SERVICE_STOPPED) {
-        // If terminated with error
-        ServiceStatus.dwWin32ExitCode = 1;
-        ServiceStatus.dwCurrentState  = SERVICE_STOPPED;
-        SetServiceStatus (hStatus, &ServiceStatus);
-    }
+    ServiceStatus.dwWin32ExitCode = main(service_argc, service_argv);
+    ServiceStatus.dwCurrentState  = SERVICE_STOPPED;
+    SetServiceStatus(hStatus, &ServiceStatus);
    return;
 }

@@ -78,6 +91,6 @@ void service_controlhandler(DWORD request)
            break;
    }
    // Report current status
-    SetServiceStatus (hStatus, &ServiceStatus);
+    SetServiceStatus(hStatus, &ServiceStatus);
    return;
 }
--- a/src/service.h
+++ b/src/service.h
--- a/src/utils/getline.c
+++ b/src/utils/getline.c
--- a/src/utils/getline.h
+++ b/src/utils/getline.h
--- a/src/utils/repl_str.c
+++ b/src/utils/repl_str.c
@@ -0,0 +1,90 @@
+#include <string.h>
+#include <stdlib.h>
+#include <stddef.h>
+
+#if (__STDC_VERSION__ >= 199901L)
+#include <stdint.h>
+#endif
+
+char *repl_str(const char *str, const char *from, const char *to) {
+
+	/* Adjust each of the below values to suit your needs. */
+
+	/* Increment positions cache size initially by this number. */
+	size_t cache_sz_inc = 16;
+	/* Thereafter, each time capacity needs to be increased,
+	 * multiply the increment by this factor. */
+	const size_t cache_sz_inc_factor = 3;
+	/* But never increment capacity by more than this number. */
+	const size_t cache_sz_inc_max = 1048576;
+
+	char *pret, *ret = NULL;
+	const char *pstr2, *pstr = str;
+	size_t i, count = 0;
+	#if (__STDC_VERSION__ >= 199901L)
+	uintptr_t *pos_cache_tmp, *pos_cache = NULL;
+	#else
+	ptrdiff_t *pos_cache_tmp, *pos_cache = NULL;
+	#endif
+	size_t cache_sz = 0;
+	size_t cpylen, orglen, retlen, tolen, fromlen = strlen(from);
+
+	/* Find all matches and cache their positions. */
+	while ((pstr2 = strstr(pstr, from)) != NULL) {
+		count++;
+
+		/* Increase the cache size when necessary. */
+		if (cache_sz < count) {
+			cache_sz += cache_sz_inc;
+			pos_cache_tmp = realloc(pos_cache, sizeof(*pos_cache) * cache_sz);
+			if (pos_cache_tmp == NULL) {
+				goto end_repl_str;
+			} else pos_cache = pos_cache_tmp;
+			cache_sz_inc *= cache_sz_inc_factor;
+			if (cache_sz_inc > cache_sz_inc_max) {
+				cache_sz_inc = cache_sz_inc_max;
+			}
+		}
+
+		pos_cache[count-1] = pstr2 - str;
+		pstr = pstr2 + fromlen;
+	}
+
+	orglen = pstr - str + strlen(pstr);
+
+	/* Allocate memory for the post-replacement string. */
+	if (count > 0) {
+		tolen = strlen(to);
+		retlen = orglen + (tolen - fromlen) * count;
+	} else	retlen = orglen;
+	ret = malloc(retlen + 1);
+	if (ret == NULL) {
+		goto end_repl_str;
+	}
+
+	if (count == 0) {
+		/* If no matches, then just duplicate the string. */
+		strcpy(ret, str);
+	} else {
+		/* Otherwise, duplicate the string whilst performing
+		 * the replacements using the position cache. */
+		pret = ret;
+		memcpy(pret, str, pos_cache[0]);
+		pret += pos_cache[0];
+		for (i = 0; i < count; i++) {
+			memcpy(pret, to, tolen);
+			pret += tolen;
+			pstr = str + pos_cache[i] + fromlen;
+			cpylen = (i == count-1 ? orglen : pos_cache[i+1]) - pos_cache[i] - fromlen;
+			memcpy(pret, pstr, cpylen);
+			pret += cpylen;
+		}
+		ret[retlen] = '\0';
+	}
+
+end_repl_str:
+	/* Free the cache and return the post-replacement string,
+	 * which will be NULL in the event of an error. */
+	free(pos_cache);
+	return ret;
+}
--- a/src/utils/repl_str.h
+++ b/src/utils/repl_str.h
@@ -0,0 +1 @@
+char *repl_str(const char *str, const char *from, const char *to);
--- a/src/utils/uthash.h
+++ b/src/utils/uthash.h
Author	SHA1	Message	Date
ValdikSS	b5d75a6c8e	Version v0.1.6	2019-10-31 22:36:29 +03:00
ValdikSS	f2de8fce8d	Fake Request Mode	2019-10-31 22:36:12 +03:00
ValdikSS	2b3e4a4683	Merge pull request #135 from alisharifi76/master Add 'GreenTunnel' to 'Similar projects' section.	2019-04-03 01:33:02 +03:00
alisharifi76	7e2f782376	Add 'GreenTunnel' to 'Similar projects' section.	2019-03-29 22:32:05 +04:30
ValdikSS	7a0b8f5229	Update issue templates	2019-02-18 01:33:03 +03:00
ValdikSS	f569c64aca	Update issue templates	2019-02-18 01:25:06 +03:00
ValdikSS	5459181fca	Merge pull request #121 from drogga/patch-1 Update README.md	2019-01-31 15:29:18 +03:00
drogga	23485b67b4	Update README.md add KB3033929 download link for Windows 7 x64	2019-01-31 21:23:41 +09:00
KOLANICH	ff4c11a6eb	Integers fixes (with small modifications), closes #84 Signed-off-by: ValdikSS <iam@valdikss.org.ru>	2019-01-03 19:31:32 +03:00
ValdikSS	1c7fe5f843	Use newlines for current options information	2019-01-03 16:10:26 +03:00
ValdikSS	46db057662	Add version number into greeting message	2019-01-03 16:10:26 +03:00
ValdikSS	b95c45ee62	Update README.md	2018-10-14 18:24:36 +03:00
ValdikSS	39507e66e0	Update README.md	2018-07-24 15:54:55 +03:00
ValdikSS	c4d0ba1297	Skip impostor and loopback packets. Fixes #53 .	2018-07-24 15:49:50 +03:00
ValdikSS	d6c2b825aa	Update README.md	2018-07-20 16:37:19 +03:00
ValdikSS	aad03f2e4a	Enable PIE, High Entropy ASLR and add more warnings to Makefile	2018-07-19 21:31:38 +03:00
ValdikSS	a028cb01f4	WinDivert 1.4 support	2018-07-19 21:31:38 +03:00
ValdikSS	38b1ff1a92	Fix -f and -e options	2018-07-19 21:31:37 +03:00
ValdikSS	3bd92d67ac	Merge pull request #83 from KOLANICH/editorconfig Added .editorconfig	2018-06-26 22:08:15 +03:00
KOLANICH	464bbcbb6b	Added .editorconfig	2018-05-16 18:35:31 +03:00
ValdikSS	50e70ace76	Handle HTTP redirects within IPv6 Flow Label = 0x00 packets	2018-02-17 18:26:16 +03:00
ValdikSS	135c97ae69	Move program source code to src directory	2018-02-17 15:22:38 +03:00
ValdikSS	c377119136	Update README.md	2018-02-17 15:21:51 +03:00
ValdikSS	185a0e0211	Merge branch 'ipv6' into masterv6	2018-02-16 23:36:26 +03:00
ValdikSS	860f483ac3	IPv6 DNS redirection	2018-02-16 19:45:55 +03:00
ValdikSS	3d36127f5b	Handle IPv6 packets and prepare for IPv6 DNS redirection	2018-02-16 17:35:24 +03:00
ValdikSS	aa28d3e12a	Make sure to search DLLs only in safe path, not in current working dir	2018-02-15 15:41:28 +03:00
ValdikSS	dc4d0a36d9	Update README.md	2018-01-21 14:37:05 +03:00
ValdikSS	cc770d302c	Add GoodbyeDPI Github link to the welcome message.	2018-01-21 14:36:41 +03:00
ValdikSS	2e23d93762	New option: --ip-id. Handles additional IP ID numbers of passive DPI.	2018-01-21 14:35:30 +03:00
ValdikSS	14ae107b53	Handle only IP IDs in [0x0; 0xF] (or→and)	2018-01-21 13:03:15 +03:00
ValdikSS	1bdfbb8c45	Move active filter template and passive filter to defines	2018-01-21 12:25:22 +03:00
ValdikSS	5eddb5f18a	Fix crash on error (free→LocalFree) and print KB3033929 message	2018-01-21 01:28:17 +03:00
ValdikSS	f638e23ab6	Fix build with -DDEBUG	2018-01-21 01:27:55 +03:00
ValdikSS	8e7f4ff505	Properly exclude Teredo	2017-12-25 00:05:28 +03:00
ValdikSS	bb8fc64f18	Handle ip.id up to 0xF. Some DPI send several TCP RST or HTTP redirection packets with increasing IP ID number. Handle them all.	2017-12-24 20:37:49 +03:00
ValdikSS	490525387d	Remove unused string	2017-12-24 20:28:25 +03:00
ValdikSS	5e9e1f0eb6	Preliminary IPv6 support. No IPv6 support in DNS redirection code. IPv6 DNS request packets would be dropped.	2017-12-24 20:21:32 +03:00
ValdikSS	3ffce30871	Minor modifications. * puts() instead of printf("%s") * strdup() instead of malloc + strcpy	2017-12-24 20:19:18 +03:00
ValdikSS	eaac2d1a80	Minor service fixes	2017-12-21 23:52:23 +03:00
ValdikSS	ccd21a4281	ntohs -> htons (they produce the same output, but still)	2017-12-21 23:50:07 +03:00
				`@@ -0,0 +1 @@`
				`char repl_str(const char str, const char from, const char to);`