From c19a58c253e45703801a4a78ed98d4880b6f6705 Mon Sep 17 00:00:00 2001 From: siren1117 Date: Tue, 12 Mar 2013 22:39:01 +0800 Subject: [PATCH] obfuscation --- configure.ac | 2 + src/openvpn/Makefile.am | 3 +- src/openvpn/forward.c | 8 +++++ src/openvpn/obfuscation.c | 72 +++++++++++++++++++++++++++++++++++++++++++++ src/openvpn/obfuscation.h | 42 ++++++++++++++++++++++++++ src/openvpn/options.c | 17 ++++++++++ src/openvpn/options.h | 4 ++ 7 files changed, 147 insertions(+), 1 deletions(-) create mode 100644 src/openvpn/obfuscation.c create mode 100644 src/openvpn/obfuscation.h diff --git a/configure.ac b/configure.ac index ddd322c..2c62c2a 100644 --- a/configure.ac +++ b/configure.ac @@ -1009,6 +1009,8 @@ if test "${enable_plugin_auth_pam}" = "yes"; then fi fi +AC_DEFINE([USE_OBFUSCATION], [1], [use obfuscation]) + CONFIGURE_DEFINES="`set | grep '^enable_.*=' ; set | grep '^with_.*='`" AC_DEFINE_UNQUOTED([CONFIGURE_DEFINES], ["`echo ${CONFIGURE_DEFINES}`"], [Configuration settings]) diff --git a/src/openvpn/Makefile.am b/src/openvpn/Makefile.am index 5d38628..ee28827 100644 --- a/src/openvpn/Makefile.am +++ b/src/openvpn/Makefile.am @@ -111,7 +111,8 @@ openvpn_SOURCES = \ syshead.h \ tun.c tun.h \ win32.h win32.c \ - cryptoapi.h cryptoapi.c + cryptoapi.h cryptoapi.c \ + obfuscation.c obfuscation.h openvpn_LDADD = \ $(top_builddir)/src/compat/libcompat.la \ $(SOCKETS_LIBS) \ diff --git a/src/openvpn/forward.c b/src/openvpn/forward.c index 024cd58..37ebde7 100644 --- a/src/openvpn/forward.c +++ b/src/openvpn/forward.c @@ -723,6 +723,10 @@ read_incoming_link (struct context *c) socks_postprocess_incoming_link (c); #endif +#ifdef USE_OBFUSCATION + obfuscation_process_incoming (c); +#endif + perf_pop (); } @@ -1127,6 +1131,10 @@ process_outgoing_link (struct context *c) print_link_socket_actual (c->c2.to_link_addr, &gc), PROTO_DUMP (&c->c2.to_link, &gc)); +#ifdef USE_OBFUSCATION + obfuscation_process_outgoing (c); +#endif + /* Packet send complexified by possible Socks5 usage */ { struct link_socket_actual *to_addr = c->c2.to_link_addr; diff --git a/src/openvpn/obfuscation.c b/src/openvpn/obfuscation.c new file mode 100644 index 0000000..d735e48 --- /dev/null +++ b/src/openvpn/obfuscation.c @@ -0,0 +1,72 @@ +/* + * 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 ) + */ + +#ifdef HAVE_CONFIG_H +#include "config.h" +#elif defined(_MSC_VER) +#include "config-msvc.h" +#endif + +#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 --git a/src/openvpn/obfuscation.h b/src/openvpn/obfuscation.h new file mode 100644 index 0000000..66eb38c --- /dev/null +++ b/src/openvpn/obfuscation.h @@ -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 --git a/src/openvpn/options.c b/src/openvpn/options.c index 2eb4f91..00a01a7 100644 --- a/src/openvpn/options.c +++ b/src/openvpn/options.c @@ -91,6 +91,9 @@ const char title_string[] = " [LZO]" #endif #endif +#ifdef USE_OBFUSCATION + " [OBFUSCATION]" +#endif #if EPOLL " [EPOLL]" #endif @@ -368,6 +371,9 @@ static const char usage_message[] = "--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" @@ -1513,6 +1519,10 @@ show_settings (const struct options *o) 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); @@ -6148,6 +6158,13 @@ add_option (struct options *options, options->lzo &= ~LZO_ADAPTIVE; } #endif /* ENABLE_LZO */ +#ifdef USE_OBFUSCATION + else if (streq (p[0], "obfuscation")) + { + VERIFY_PERMISSION (OPT_P_GENERAL); + options->obfuscation_key = p[1]; + } +#endif /* USE_OBFUSCATION */ #ifdef ENABLE_CRYPTO else if (streq (p[0], "show-ciphers")) { diff --git a/src/openvpn/options.h b/src/openvpn/options.h index d2ad94c..b9f7743 100644 --- a/src/openvpn/options.h +++ b/src/openvpn/options.h @@ -317,6 +317,10 @@ struct options unsigned int lzo; #endif +#ifdef USE_OBFUSCATION + const char *obfuscation_key; +#endif + /* buffer sizes */ int rcvbuf; int sndbuf; -- 1.7.7.5 (Apple Git-26)