diff options
Diffstat (limited to 'plugin/examples')
| -rw-r--r-- | plugin/examples/README | 16 | ||||
| -rwxr-xr-x | plugin/examples/build | 14 | ||||
| -rw-r--r-- | plugin/examples/log.c | 184 | ||||
| -rw-r--r-- | plugin/examples/simple.c | 120 | ||||
| -rwxr-xr-x | plugin/examples/simple.def | 6 | ||||
| -rwxr-xr-x | plugin/examples/winbuild | 18 |
6 files changed, 358 insertions, 0 deletions
diff --git a/plugin/examples/README b/plugin/examples/README new file mode 100644 index 0000000..4400cd3 --- /dev/null +++ b/plugin/examples/README @@ -0,0 +1,16 @@ +OpenVPN plugin examples. + +Examples provided: + +simple.c -- using the --auth-user-pass-verify callback, verify + that the username/password is "foo"/"bar". + +To build: + + ./build simple (Linux/BSD/etc.) + ./winbuild simple (MinGW on Windows) + +To use in OpenVPN, add to config file: + + plugin simple.so (Linux/BSD/etc.) + plugin simple.dll (MinGW on Windows) diff --git a/plugin/examples/build b/plugin/examples/build new file mode 100755 index 0000000..5907afa --- /dev/null +++ b/plugin/examples/build @@ -0,0 +1,14 @@ +#!/bin/sh + +# +# Build an OpenVPN plugin module on *nix. The argument should +# be the base name of the C source file (without the .c). +# + +# This directory is where we will look for openvpn-plugin.h +INCLUDE="-I../.." + +CC_FLAGS="-O2 -Wall -g" + +gcc $CC_FLAGS -fPIC -c $INCLUDE $1.c && \ +gcc $CC_FLAGS -fPIC -shared -Wl,-soname,$1.so -o $1.so $1.o -lc diff --git a/plugin/examples/log.c b/plugin/examples/log.c new file mode 100644 index 0000000..1cc4650 --- /dev/null +++ b/plugin/examples/log.c @@ -0,0 +1,184 @@ +/* + * 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. <sales@openvpn.net> + * + * 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 + */ + +/* + * This plugin is similar to simple.c, except it also logs extra information + * to stdout for every plugin method called by OpenVPN. + * + * See the README file for build instructions. + */ + +#include <stdio.h> +#include <string.h> +#include <stdlib.h> + +#include "openvpn-plugin.h" + +/* + * Our context, where we keep our state. + */ +struct plugin_context { + const char *username; + const char *password; +}; + +/* + * Given an environmental variable name, search + * the envp array for its value, returning it + * if found or NULL otherwise. + */ +static const char * +get_env (const char *name, const char *envp[]) +{ + if (envp) + { + int i; + const int namelen = strlen (name); + for (i = 0; envp[i]; ++i) + { + if (!strncmp (envp[i], name, namelen)) + { + const char *cp = envp[i] + namelen; + if (*cp == '=') + return cp + 1; + } + } + } + return NULL; +} + +OPENVPN_EXPORT openvpn_plugin_handle_t +openvpn_plugin_open_v1 (unsigned int *type_mask, const char *argv[], const char *envp[]) +{ + struct plugin_context *context; + + /* + * Allocate our context + */ + context = (struct plugin_context *) calloc (1, sizeof (struct plugin_context)); + + /* + * Set the username/password we will require. + */ + context->username = "foo"; + context->password = "bar"; + + /* + * Which callbacks to intercept. + */ + *type_mask = + OPENVPN_PLUGIN_MASK (OPENVPN_PLUGIN_UP) | + OPENVPN_PLUGIN_MASK (OPENVPN_PLUGIN_DOWN) | + OPENVPN_PLUGIN_MASK (OPENVPN_PLUGIN_ROUTE_UP) | + OPENVPN_PLUGIN_MASK (OPENVPN_PLUGIN_IPCHANGE) | + OPENVPN_PLUGIN_MASK (OPENVPN_PLUGIN_TLS_VERIFY) | + OPENVPN_PLUGIN_MASK (OPENVPN_PLUGIN_AUTH_USER_PASS_VERIFY) | + OPENVPN_PLUGIN_MASK (OPENVPN_PLUGIN_CLIENT_CONNECT_V2) | + OPENVPN_PLUGIN_MASK (OPENVPN_PLUGIN_CLIENT_DISCONNECT) | + OPENVPN_PLUGIN_MASK (OPENVPN_PLUGIN_LEARN_ADDRESS) | + OPENVPN_PLUGIN_MASK (OPENVPN_PLUGIN_TLS_FINAL); + + return (openvpn_plugin_handle_t) context; +} + +void +show (const int type, const char *argv[], const char *envp[]) +{ + size_t i; + switch (type) + { + case OPENVPN_PLUGIN_UP: + printf ("OPENVPN_PLUGIN_UP\n"); + break; + case OPENVPN_PLUGIN_DOWN: + printf ("OPENVPN_PLUGIN_DOWN\n"); + break; + case OPENVPN_PLUGIN_ROUTE_UP: + printf ("OPENVPN_PLUGIN_ROUTE_UP\n"); + break; + case OPENVPN_PLUGIN_IPCHANGE: + printf ("OPENVPN_PLUGIN_IPCHANGE\n"); + break; + case OPENVPN_PLUGIN_TLS_VERIFY: + printf ("OPENVPN_PLUGIN_TLS_VERIFY\n"); + break; + case OPENVPN_PLUGIN_AUTH_USER_PASS_VERIFY: + printf ("OPENVPN_PLUGIN_AUTH_USER_PASS_VERIFY\n"); + break; + case OPENVPN_PLUGIN_CLIENT_CONNECT_V2: + printf ("OPENVPN_PLUGIN_CLIENT_CONNECT_V2\n"); + break; + case OPENVPN_PLUGIN_CLIENT_DISCONNECT: + printf ("OPENVPN_PLUGIN_CLIENT_DISCONNECT\n"); + break; + case OPENVPN_PLUGIN_LEARN_ADDRESS: + printf ("OPENVPN_PLUGIN_LEARN_ADDRESS\n"); + break; + case OPENVPN_PLUGIN_TLS_FINAL: + printf ("OPENVPN_PLUGIN_TLS_FINAL\n"); + break; + default: + printf ("OPENVPN_PLUGIN_?\n"); + break; + } + + printf ("ARGV\n"); + for (i = 0; argv[i] != NULL; ++i) + printf ("%d '%s'\n", (int)i, argv[i]); + + printf ("ENVP\n"); + for (i = 0; envp[i] != NULL; ++i) + printf ("%d '%s'\n", (int)i, envp[i]); +} + +OPENVPN_EXPORT int +openvpn_plugin_func_v1 (openvpn_plugin_handle_t handle, const int type, const char *argv[], const char *envp[]) +{ + struct plugin_context *context = (struct plugin_context *) handle; + + show (type, argv, envp); + + /* check entered username/password against what we require */ + if (type == OPENVPN_PLUGIN_AUTH_USER_PASS_VERIFY) + { + /* get username/password from envp string array */ + const char *username = get_env ("username", envp); + const char *password = get_env ("password", envp); + + if (username && !strcmp (username, context->username) + && password && !strcmp (password, context->password)) + return OPENVPN_PLUGIN_FUNC_SUCCESS; + else + return OPENVPN_PLUGIN_FUNC_ERROR; + } + else + return OPENVPN_PLUGIN_FUNC_SUCCESS; +} + +OPENVPN_EXPORT void +openvpn_plugin_close_v1 (openvpn_plugin_handle_t handle) +{ + struct plugin_context *context = (struct plugin_context *) handle; + free (context); +} diff --git a/plugin/examples/simple.c b/plugin/examples/simple.c new file mode 100644 index 0000000..f26d89f --- /dev/null +++ b/plugin/examples/simple.c @@ -0,0 +1,120 @@ +/* + * 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. <sales@openvpn.net> + * + * 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 + */ + +/* + * This file implements a simple OpenVPN plugin module which + * will examine the username/password provided by a client, + * and make an accept/deny determination. Will run + * on Windows or *nix. + * + * See the README file for build instructions. + */ + +#include <stdio.h> +#include <string.h> +#include <stdlib.h> + +#include "openvpn-plugin.h" + +/* + * Our context, where we keep our state. + */ +struct plugin_context { + const char *username; + const char *password; +}; + +/* + * Given an environmental variable name, search + * the envp array for its value, returning it + * if found or NULL otherwise. + */ +static const char * +get_env (const char *name, const char *envp[]) +{ + if (envp) + { + int i; + const int namelen = strlen (name); + for (i = 0; envp[i]; ++i) + { + if (!strncmp (envp[i], name, namelen)) + { + const char *cp = envp[i] + namelen; + if (*cp == '=') + return cp + 1; + } + } + } + return NULL; +} + +OPENVPN_EXPORT openvpn_plugin_handle_t +openvpn_plugin_open_v1 (unsigned int *type_mask, const char *argv[], const char *envp[]) +{ + struct plugin_context *context; + + /* + * Allocate our context + */ + context = (struct plugin_context *) calloc (1, sizeof (struct plugin_context)); + + /* + * Set the username/password we will require. + */ + context->username = "foo"; + context->password = "bar"; + + /* + * We are only interested in intercepting the + * --auth-user-pass-verify callback. + */ + *type_mask = OPENVPN_PLUGIN_MASK (OPENVPN_PLUGIN_AUTH_USER_PASS_VERIFY); + + return (openvpn_plugin_handle_t) context; +} + +OPENVPN_EXPORT int +openvpn_plugin_func_v1 (openvpn_plugin_handle_t handle, const int type, const char *argv[], const char *envp[]) +{ + struct plugin_context *context = (struct plugin_context *) handle; + + /* get username/password from envp string array */ + const char *username = get_env ("username", envp); + const char *password = get_env ("password", envp); + + /* check entered username/password against what we require */ + if (username && !strcmp (username, context->username) + && password && !strcmp (password, context->password)) + return OPENVPN_PLUGIN_FUNC_SUCCESS; + else + return OPENVPN_PLUGIN_FUNC_ERROR; +} + +OPENVPN_EXPORT void +openvpn_plugin_close_v1 (openvpn_plugin_handle_t handle) +{ + struct plugin_context *context = (struct plugin_context *) handle; + free (context); +} diff --git a/plugin/examples/simple.def b/plugin/examples/simple.def new file mode 100755 index 0000000..a87507d --- /dev/null +++ b/plugin/examples/simple.def @@ -0,0 +1,6 @@ +LIBRARY OpenVPN_PLUGIN_SAMPLE +DESCRIPTION "Sample OpenVPN plug-in module." +EXPORTS + openvpn_plugin_open_v1 @1 + openvpn_plugin_func_v1 @2 + openvpn_plugin_close_v1 @3 diff --git a/plugin/examples/winbuild b/plugin/examples/winbuild new file mode 100755 index 0000000..97e724a --- /dev/null +++ b/plugin/examples/winbuild @@ -0,0 +1,18 @@ +# +# Build an OpenVPN plugin module on Windows/MinGW. +# The argument should be the base name of the C source file +# (without the .c). +# + +# This directory is where we will look for openvpn-plugin.h +INCLUDE="-I.." + +CC_FLAGS="-O2 -Wall" + +gcc -DBUILD_DLL $CC_FLAGS $INCLUDE -c $1.c +gcc --disable-stdcall-fixup -mdll -DBUILD_DLL -o junk.tmp -Wl,--base-file,base.tmp $1.o +rm junk.tmp +dlltool --dllname $1.dll --base-file base.tmp --output-exp temp.exp --input-def $1.def +rm base.tmp +gcc --enable-stdcall-fixup -mdll -DBUILD_DLL -o $1.dll $1.o -Wl,temp.exp +rm temp.exp |