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-rw-r--r--plugin.c394
1 files changed, 394 insertions, 0 deletions
diff --git a/plugin.c b/plugin.c
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+++ b/plugin.c
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+/*
+ * 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) 2002-2005 OpenVPN Solutions LLC <info@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
+ */
+
+#ifdef WIN32
+#include "config-win32.h"
+#else
+#include "config.h"
+#endif
+
+#include "syshead.h"
+
+#ifdef ENABLE_PLUGIN
+
+#include "buffer.h"
+#include "error.h"
+#include "misc.h"
+#include "plugin.h"
+
+#include "memdbg.h"
+
+#define PLUGIN_SYMBOL_REQUIRED (1<<0)
+
+/* used only for program aborts */
+static struct plugin_list *static_plugin_list = NULL; /* GLOBAL */
+
+static void
+plugin_show_string_array (int msglevel, const char *name, const char *array[])
+{
+ int i;
+ for (i = 0; array[i]; ++i)
+ msg (msglevel, "%s[%d] = '%s'", name, i, array[i]);
+}
+
+static void
+plugin_show_args_env (int msglevel, const char *argv[], const char *envp[])
+{
+ if (check_debug_level (msglevel))
+ {
+ plugin_show_string_array (msglevel, "ARGV", argv);
+ plugin_show_string_array (msglevel, "ENVP", envp);
+ }
+}
+
+static const char *
+plugin_type_name (const int type)
+{
+ switch (type)
+ {
+ case OPENVPN_PLUGIN_UP:
+ return "PLUGIN_UP";
+ case OPENVPN_PLUGIN_DOWN:
+ return "PLUGIN_DOWN";
+ case OPENVPN_PLUGIN_ROUTE_UP:
+ return "PLUGIN_ROUTE_UP";
+ case OPENVPN_PLUGIN_IPCHANGE:
+ return "PLUGIN_IPCHANGE";
+ case OPENVPN_PLUGIN_TLS_VERIFY:
+ return "PLUGIN_TLS_VERIFY";
+ case OPENVPN_PLUGIN_AUTH_USER_PASS_VERIFY:
+ return "PLUGIN_AUTH_USER_PASS_VERIFY";
+ case OPENVPN_PLUGIN_CLIENT_CONNECT:
+ return "PLUGIN_CLIENT_CONNECT";
+ case OPENVPN_PLUGIN_CLIENT_DISCONNECT:
+ return "PLUGIN_CLIENT_DISCONNECT";
+ case OPENVPN_PLUGIN_LEARN_ADDRESS:
+ return "PLUGIN_LEARN_ADDRESS";
+ default:
+ return "PLUGIN_???";
+ }
+}
+
+static const char *
+plugin_mask_string (const unsigned int type_mask, struct gc_arena *gc)
+{
+ struct buffer out = alloc_buf_gc (256, gc);
+ bool first = true;
+ int i;
+
+ for (i = 0; i < OPENVPN_PLUGIN_N; ++i)
+ {
+ if (OPENVPN_PLUGIN_MASK (i) & type_mask)
+ {
+ if (!first)
+ buf_printf (&out, "|");
+ buf_printf (&out, "%s", plugin_type_name (i));
+ first = false;
+ }
+ }
+ return BSTR (&out);
+}
+
+static inline unsigned int
+plugin_supported_types (void)
+{
+ return ((1<<OPENVPN_PLUGIN_N)-1);
+}
+
+struct plugin_option_list *
+plugin_option_list_new (struct gc_arena *gc)
+{
+ struct plugin_option_list *ret;
+ ALLOC_OBJ_CLEAR_GC (ret, struct plugin_option_list, gc);
+ return ret;
+}
+
+bool
+plugin_option_list_add (struct plugin_option_list *list, const char *so_pathname, const char *args)
+{
+ if (list->n < MAX_PLUGINS)
+ {
+ struct plugin_option *o = &list->plugins[list->n++];
+ o->so_pathname = so_pathname;
+ o->args = args;
+ return true;
+ }
+ else
+ return false;
+}
+
+#ifdef ENABLE_DEBUG
+void
+plugin_option_list_print (const struct plugin_option_list *list, int msglevel)
+{
+ int i;
+ for (i = 0; i < list->n; ++i)
+ {
+ const struct plugin_option *o = &list->plugins[i];
+ msg (msglevel, " plugin[%d] %s '%s'", i, o->so_pathname, o->args);
+ }
+}
+#endif
+
+#if defined(USE_LIBDL)
+
+static void
+libdl_resolve_symbol (void *handle, void **dest, const char *symbol, const char *plugin_name, const unsigned int flags)
+{
+ *dest = dlsym (handle, symbol);
+ if ((flags & PLUGIN_SYMBOL_REQUIRED) && !*dest)
+ msg (M_FATAL, "PLUGIN: could not find required symbol '%s' in plugin shared object %s: %s", symbol, plugin_name, dlerror());
+}
+
+#elif defined(USE_LOAD_LIBRARY)
+
+static void
+dll_resolve_symbol (HMODULE module, void **dest, const char *symbol, const char *plugin_name, const unsigned int flags)
+{
+ *dest = GetProcAddress (module, symbol);
+ if ((flags & PLUGIN_SYMBOL_REQUIRED) && !*dest)
+ msg (M_FATAL, "PLUGIN: could not find required symbol '%s' in plugin DLL %s", symbol, plugin_name);
+}
+
+#endif
+
+static void
+plugin_init_item (struct plugin *p, const struct plugin_option *o, const char **envp)
+{
+ struct gc_arena gc = gc_new ();
+ const char **argv = make_arg_array (o->so_pathname, o->args, &gc);
+ p->so_pathname = o->so_pathname;
+ p->plugin_type_mask = plugin_supported_types ();
+
+#if defined(USE_LIBDL)
+ p->handle = dlopen (p->so_pathname, RTLD_NOW);
+ if (!p->handle)
+ msg (M_ERR, "PLUGIN_INIT: could not load plugin shared object %s: %s", p->so_pathname, dlerror());
+ libdl_resolve_symbol (p->handle, (void*)&p->open, "openvpn_plugin_open_v1", p->so_pathname, PLUGIN_SYMBOL_REQUIRED);
+ libdl_resolve_symbol (p->handle, (void*)&p->func, "openvpn_plugin_func_v1", p->so_pathname, PLUGIN_SYMBOL_REQUIRED);
+ libdl_resolve_symbol (p->handle, (void*)&p->close, "openvpn_plugin_close_v1", p->so_pathname, PLUGIN_SYMBOL_REQUIRED);
+ libdl_resolve_symbol (p->handle, (void*)&p->abort, "openvpn_plugin_abort_v1", p->so_pathname, 0);
+#elif defined(USE_LOAD_LIBRARY)
+ p->module = LoadLibrary (p->so_pathname);
+ if (!p->module)
+ msg (M_ERR, "PLUGIN_INIT: could not load plugin DLL: %s", p->so_pathname);
+ dll_resolve_symbol (p->module, (void*)&p->open, "openvpn_plugin_open_v1", p->so_pathname, PLUGIN_SYMBOL_REQUIRED);
+ dll_resolve_symbol (p->module, (void*)&p->func, "openvpn_plugin_func_v1", p->so_pathname, PLUGIN_SYMBOL_REQUIRED);
+ dll_resolve_symbol (p->module, (void*)&p->close, "openvpn_plugin_close_v1", p->so_pathname, PLUGIN_SYMBOL_REQUIRED);
+ dll_resolve_symbol (p->module, (void*)&p->abort, "openvpn_plugin_abort_v1", p->so_pathname, 0);
+#endif
+
+ dmsg (D_PLUGIN_DEBUG, "PLUGIN_INIT: PRE");
+ plugin_show_args_env (D_PLUGIN_DEBUG, argv, envp);
+
+ /*
+ * Call the plugin initialization
+ */
+ p->plugin_handle = (*p->open)(&p->plugin_type_mask, argv, envp);
+
+ msg (D_PLUGIN, "PLUGIN_INIT: POST %s '%s' intercepted=%s",
+ p->so_pathname,
+ o->args ? o->args : "[NULL]",
+ plugin_mask_string (p->plugin_type_mask, &gc));
+
+ if ((p->plugin_type_mask | plugin_supported_types()) != plugin_supported_types())
+ msg (M_FATAL, "PLUGIN_INIT: plugin %s expressed interest in unsupported plugin types: [want=0x%08x, have=0x%08x]",
+ p->so_pathname,
+ p->plugin_type_mask,
+ plugin_supported_types());
+
+ if (p->plugin_handle == NULL)
+ msg (M_FATAL, "PLUGIN_INIT: plugin initialization function failed: %s",
+ p->so_pathname);
+
+ gc_free (&gc);
+}
+
+static int
+plugin_call_item (const struct plugin *p, const int type, const char *args, const char **envp)
+{
+ int status = OPENVPN_PLUGIN_FUNC_SUCCESS;
+
+ if (p->plugin_type_mask & OPENVPN_PLUGIN_MASK (type))
+ {
+ struct gc_arena gc = gc_new ();
+ const char **argv = make_arg_array (p->so_pathname, args, &gc);
+
+ dmsg (D_PLUGIN_DEBUG, "PLUGIN_CALL: PRE type=%s", plugin_type_name (type));
+ plugin_show_args_env (D_PLUGIN_DEBUG, argv, envp);
+
+ /*
+ * Call the plugin work function
+ */
+ status = (*p->func)(p->plugin_handle, type, argv, envp);
+
+ msg (D_PLUGIN, "PLUGIN_CALL: POST %s/%s status=%d",
+ p->so_pathname,
+ plugin_type_name (type),
+ status);
+
+ if (status != OPENVPN_PLUGIN_FUNC_SUCCESS)
+ msg (M_WARN, "PLUGIN_CALL: plugin function %s failed with status %d: %s",
+ plugin_type_name (type),
+ status,
+ p->so_pathname);
+
+ gc_free (&gc);
+ }
+ return status;
+}
+
+static void
+plugin_close_item (const struct plugin *p)
+{
+ msg (D_PLUGIN, "PLUGIN_CLOSE: %s", p->so_pathname);
+
+ /*
+ * Call the plugin close function
+ */
+ (*p->close)(p->plugin_handle);
+
+#if defined(USE_LIBDL)
+ if (dlclose (p->handle))
+ msg (M_WARN, "PLUGIN_CLOSE: dlclose() failed on plugin: %s", p->so_pathname);
+#elif defined(USE_LOAD_LIBRARY)
+ if (!FreeLibrary (p->module))
+ msg (M_WARN, "PLUGIN_CLOSE: FreeLibrary() failed on plugin: %s", p->so_pathname);
+#endif
+}
+
+static void
+plugin_abort_item (const struct plugin *p)
+{
+ /*
+ * Call the plugin abort function
+ */
+ if (p->abort)
+ (*p->abort)(p->plugin_handle);
+}
+
+struct plugin_list *
+plugin_list_open (const struct plugin_option_list *list, const struct env_set *es)
+{
+ struct gc_arena gc = gc_new ();
+ int i;
+ struct plugin_list *pl;
+ const char **envp;
+
+ ALLOC_OBJ_CLEAR (pl, struct plugin_list);
+ static_plugin_list = pl;
+
+ envp = make_env_array (es, &gc);
+
+ for (i = 0; i < list->n; ++i)
+ {
+ plugin_init_item (&pl->plugins[i], &list->plugins[i], envp);
+ pl->n = i + 1;
+ }
+
+ gc_free (&gc);
+ return pl;
+}
+
+int
+plugin_call (const struct plugin_list *pl, const int type, const char *args, struct env_set *es)
+{
+ int count = 0;
+
+ if (plugin_defined (pl, type))
+ {
+ struct gc_arena gc = gc_new ();
+ int i;
+ const char **envp;
+
+ mutex_lock_static (L_PLUGIN);
+
+ setenv_del (es, "script_type");
+ envp = make_env_array (es, &gc);
+
+ for (i = 0; i < pl->n; ++i)
+ {
+ if (!plugin_call_item (&pl->plugins[i], type, args, envp))
+ ++count;
+ }
+
+ mutex_unlock_static (L_PLUGIN);
+
+ gc_free (&gc);
+ }
+
+ return count == pl->n ? 0 : 1; /* if any one plugin in the chain failed, return failure (1) */
+}
+
+void
+plugin_list_close (struct plugin_list *pl)
+{
+ static_plugin_list = NULL;
+ if (pl)
+ {
+ int i;
+
+ for (i = 0; i < pl->n; ++i)
+ plugin_close_item (&pl->plugins[i]);
+ free (pl);
+ }
+}
+
+void
+plugin_abort (void)
+{
+ struct plugin_list *pl = static_plugin_list;
+ static_plugin_list = NULL;
+ if (pl)
+ {
+ int i;
+
+ for (i = 0; i < pl->n; ++i)
+ plugin_abort_item (&pl->plugins[i]);
+ }
+}
+
+bool
+plugin_defined (const struct plugin_list *pl, const int type)
+{
+ bool ret = false;
+ if (pl)
+ {
+ int i;
+ const unsigned int mask = OPENVPN_PLUGIN_MASK (type);
+ for (i = 0; i < pl->n; ++i)
+ {
+ if (pl->plugins[i].plugin_type_mask & mask)
+ {
+ ret = true;
+ break;
+ }
+ }
+ }
+ return ret;
+}
+
+#else
+static void dummy(void) {}
+#endif /* ENABLE_PLUGIN */