diff -urN openvpn-2.2.1.orig/configure.ac openvpn-2.2.1/configure.ac --- openvpn-2.2.1.orig/configure.ac 2012-10-29 11:08:47.000000000 +0800 +++ openvpn-2.2.1/configure.ac 2013-01-23 15:28:11.000000000 +0800 @@ -771,6 +771,7 @@ fi AC_DEFINE(USE_SSL, 1, [Use OpenSSL SSL library]) + AC_DEFINE(USE_OBFUSCATION, 1, [Use Obfuscation]) fi fi diff -urN openvpn-2.2.1.orig/forward.c openvpn-2.2.1/forward.c --- openvpn-2.2.1.orig/forward.c 2012-10-29 11:08:47.000000000 +0800 +++ openvpn-2.2.1/forward.c 2012-12-29 15:42:38.000000000 +0800 @@ -602,6 +602,22 @@ tv_add (&c->c2.timeval, &c->c2.timeout_random_component); } +#ifdef USE_OBFUSCATION + +static inline void +obfuscation_postprocess_incoming_link(struct context *c) +{ + obfuscation_process_incoming (c); +} + +static inline void +obfuscation_preprocess_outgoing_link (struct context *c) +{ + obfuscation_process_outgoing (c); +} + +#endif /* USE_OBFUSCATION */ + #ifdef ENABLE_SOCKS /* @@ -718,6 +734,10 @@ socks_postprocess_incoming_link (c); #endif +#ifdef USE_OBFUSCATION + obfuscation_postprocess_incoming_link (c); +#endif + perf_pop (); } @@ -1106,6 +1126,10 @@ print_link_socket_actual (c->c2.to_link_addr, &gc), PROTO_DUMP (&c->c2.to_link, &gc)); +#ifdef USE_OBFUSCATION + obfuscation_preprocess_outgoing_link (c); +#endif + /* Packet send complexified by possible Socks5 usage */ { struct link_socket_actual *to_addr = c->c2.to_link_addr; diff -urN openvpn-2.2.1.orig/Makefile.am openvpn-2.2.1/Makefile.am --- openvpn-2.2.1.orig/Makefile.am 2011-06-24 14:13:38.000000000 +0800 +++ openvpn-2.2.1/Makefile.am 2012-12-29 15:20:24.000000000 +0800 @@ -142,7 +142,8 @@ syshead.h \ tun.c tun.h \ win32.h win32.c \ - cryptoapi.h cryptoapi.c + cryptoapi.h cryptoapi.c \ + obfuscation.c obfuscation.h nodist_openvpn_SOURCES = configure.h options.$(OBJEXT): configure.h diff -urN openvpn-2.2.1.orig/obfuscation.c openvpn-2.2.1/obfuscation.c --- openvpn-2.2.1.orig/obfuscation.c 1970-01-01 08:00:00.000000000 +0800 +++ openvpn-2.2.1/obfuscation.c 2013-01-23 13:08:28.000000000 +0800 @@ -0,0 +1,66 @@ +/* + * OpenVPN -- An application to securely tunnel IP networks + * over a single TCP/UDP port, with support for SSL/TLS-based + * session authentication and key exchange, + * packet encryption, packet authentication, and + * packet compression. + * + * Copyright (C) 2002-2010 OpenVPN Technologies, Inc. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 + * as published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program (see the file COPYING included with this + * distribution); if not, write to the Free Software Foundation, Inc., + * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + */ + +/* + * 2012-12-18: Added obfuscation support + * (siren1117 ) + */ + +#include "syshead.h" + +#ifdef USE_OBFUSCATION + +#include +#include "forward.h" +#include "forward-inline.h" +#include "obfuscation.h" + +static void +obfuscation_process_buf (struct context *c, + struct buffer *buf) +{ + RC4_KEY key; + RC4_set_key(&key, strlen(c->options.obfuscation_key), (unsigned char *)c->options.obfuscation_key); + RC4(&key, buf->len, BPTR(buf), BPTR(buf)); +} + +void +obfuscation_process_incoming (struct context *c) +{ + if (BLEN (&c->c2.buf) && c->options.obfuscation_key) { + obfuscation_process_buf(c, &c->c2.buf); + } +} + +void +obfuscation_process_outgoing (struct context *c) +{ + if (BLEN (&c->c2.to_link) && c->options.obfuscation_key) { + obfuscation_process_buf(c, &c->c2.to_link); + } +} + +#else +static void dummy(void) {} +#endif /* USE_OBFUSCATION */ diff -urN openvpn-2.2.1.orig/obfuscation.h openvpn-2.2.1/obfuscation.h --- openvpn-2.2.1.orig/obfuscation.h 1970-01-01 08:00:00.000000000 +0800 +++ openvpn-2.2.1/obfuscation.h 2013-01-23 13:08:44.000000000 +0800 @@ -0,0 +1,42 @@ +/* + * OpenVPN -- An application to securely tunnel IP networks + * over a single TCP/UDP port, with support for SSL/TLS-based + * session authentication and key exchange, + * packet encryption, packet authentication, and + * packet compression. + * + * Copyright (C) 2002-2010 OpenVPN Technologies, Inc. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 + * as published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program (see the file COPYING included with this + * distribution); if not, write to the Free Software Foundation, Inc., + * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + */ + +/* + * 2012-12-18: Added obfuscation support + * (siren1117 ) + */ + +#ifndef OBFUSCATION_H +#define OBFUSCATION_H + +#ifdef USE_OBFUSCATION + +#include "openvpn.h" + +void obfuscation_process_incoming_udp (struct context *c); + +void obfuscation_process_outgoing_udp (struct context *c); + +#endif +#endif diff -urN openvpn-2.2.1.orig/options.c openvpn-2.2.1/options.c --- openvpn-2.2.1.orig/options.c 2012-10-29 11:08:47.000000000 +0800 +++ openvpn-2.2.1/options.c 2013-01-23 13:44:18.000000000 +0800 @@ -67,6 +67,9 @@ #ifdef USE_LZO " [LZO" LZO_VERSION_NUM "]" #endif +#ifdef USE_OBFUSCATION + " [OBFUSCATION]" +#endif #if EPOLL " [EPOLL]" #endif @@ -342,6 +345,9 @@ "--comp-noadapt : Don't use adaptive compression when --comp-lzo\n" " is specified.\n" #endif +#ifdef USE_OBFUSCATION + "--obfuscation key : Use key to obfuscate data.\n" +#endif #ifdef ENABLE_MANAGEMENT "--management ip port [pass] : Enable a TCP server on ip:port to handle\n" " management functions. pass is a password file\n" @@ -1422,6 +1428,10 @@ SHOW_INT (lzo); #endif +#ifdef USE_OBFUSCATION + SHOW_STR (obfuscation_key); +#endif + SHOW_STR (route_script); SHOW_STR (route_default_gateway); SHOW_INT (route_default_metric); @@ -5792,6 +5802,13 @@ options->lzo &= ~LZO_ADAPTIVE; } #endif /* USE_LZO */ +#ifdef USE_OBFUSCATION + else if (streq (p[0], "obfuscation")) + { + VERIFY_PERMISSION (OPT_P_GENERAL); + options->obfuscation_key = p[1]; + } +#endif /* USE_OBFUSCATION */ #ifdef USE_CRYPTO else if (streq (p[0], "show-ciphers")) { diff -urN openvpn-2.2.1.orig/options.h openvpn-2.2.1/options.h --- openvpn-2.2.1.orig/options.h 2012-10-29 11:08:47.000000000 +0800 +++ openvpn-2.2.1/options.h 2013-01-23 13:09:34.000000000 +0800 @@ -312,6 +312,10 @@ unsigned int lzo; #endif +#ifdef USE_OBFUSCATION + const char *obfuscation_key; +#endif + /* buffer sizes */ int rcvbuf; int sndbuf;