Files
asterisk/apps/app_page.c
Terry Wilson b3ea953313 Don't overflow when paging more than 128 extensions
The number of available slots for calls in app_page was hardcoded to 128.
Proper bounds checking was not in place to enforce this limit, so if more than
128 extensions were passed to the Page() app, Asterisk would crash.  This patch
instead dynamically allocates memory for the ast_dial structures and removes
the (non-functional) arbitrary limit.

This issue would have special importance to anyone who is dynamically creating
the argument passed to the Page application and allowing more than 128
extensions to be added by an outside user via some external interface.

The patch posted by a_villacis was slightly modified for some coding guidelines
and other cleanups.  Thanks, a_villacis!
(closes issue #14217)
Reported by: a_villacis
Patches: 
      20080912-asterisk-app_page-fix-buffer-overflow.patch uploaded by a (license 660)
Tested by: otherwiseguy


git-svn-id: https://origsvn.digium.com/svn/asterisk/branches/1.4@168593 65c4cc65-6c06-0410-ace0-fbb531ad65f3
2009-01-14 01:27:18 +00:00

218 lines
5.5 KiB
C

/*
* Asterisk -- An open source telephony toolkit.
*
* Copyright (c) 2004 - 2006 Digium, Inc. All rights reserved.
*
* Mark Spencer <markster@digium.com>
*
* This code is released under the GNU General Public License
* version 2.0. See LICENSE for more information.
*
* See http://www.asterisk.org for more information about
* the Asterisk project. Please do not directly contact
* any of the maintainers of this project for assistance;
* the project provides a web site, mailing lists and IRC
* channels for your use.
*
*/
/*! \file
*
* \brief page() - Paging application
*
* \author Mark Spencer <markster@digium.com>
*
* \ingroup applications
*/
/*** MODULEINFO
<depend>dahdi</depend>
<depend>app_meetme</depend>
***/
#include "asterisk.h"
ASTERISK_FILE_VERSION(__FILE__, "$Revision$")
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <errno.h>
#include "asterisk/options.h"
#include "asterisk/logger.h"
#include "asterisk/channel.h"
#include "asterisk/pbx.h"
#include "asterisk/module.h"
#include "asterisk/file.h"
#include "asterisk/app.h"
#include "asterisk/chanvars.h"
#include "asterisk/utils.h"
#include "asterisk/dial.h"
#include "asterisk/devicestate.h"
static const char *app_page= "Page";
static const char *page_synopsis = "Pages phones";
static const char *page_descrip =
"Page(Technology/Resource&Technology2/Resource2[|options])\n"
" Places outbound calls to the given technology / resource and dumps\n"
"them into a conference bridge as muted participants. The original\n"
"caller is dumped into the conference as a speaker and the room is\n"
"destroyed when the original caller leaves. Valid options are:\n"
" d - full duplex audio\n"
" q - quiet, do not play beep to caller\n"
" r - record the page into a file (see 'r' for app_meetme)\n";
enum {
PAGE_DUPLEX = (1 << 0),
PAGE_QUIET = (1 << 1),
PAGE_RECORD = (1 << 2),
} page_opt_flags;
AST_APP_OPTIONS(page_opts, {
AST_APP_OPTION('d', PAGE_DUPLEX),
AST_APP_OPTION('q', PAGE_QUIET),
AST_APP_OPTION('r', PAGE_RECORD),
});
static int page_exec(struct ast_channel *chan, void *data)
{
struct ast_module_user *u;
char *options, *tech, *resource, *tmp, *tmp2;
char meetmeopts[88], originator[AST_CHANNEL_NAME];
struct ast_flags flags = { 0 };
unsigned int confid = ast_random();
struct ast_app *app;
int res = 0, pos = 0, i = 0;
struct ast_dial **dial_list;
unsigned int num_dials;
if (ast_strlen_zero(data)) {
ast_log(LOG_WARNING, "This application requires at least one argument (destination(s) to page)\n");
return -1;
}
u = ast_module_user_add(chan);
if (!(app = pbx_findapp("MeetMe"))) {
ast_log(LOG_WARNING, "There is no MeetMe application available!\n");
ast_module_user_remove(u);
return -1;
};
options = ast_strdupa(data);
ast_copy_string(originator, chan->name, sizeof(originator));
if ((tmp = strchr(originator, '-')))
*tmp = '\0';
tmp = strsep(&options, "|");
if (options)
ast_app_parse_options(page_opts, &flags, NULL, options);
snprintf(meetmeopts, sizeof(meetmeopts), "MeetMe|%ud|%s%sqxdw(5)", confid, (ast_test_flag(&flags, PAGE_DUPLEX) ? "" : "m"),
(ast_test_flag(&flags, PAGE_RECORD) ? "r" : "") );
/* Count number of extensions in list by number of ampersands + 1 */
num_dials = 1;
tmp2 = tmp;
while (*tmp2 && *tmp2++ == '&') {
num_dials++;
}
if (!(dial_list = ast_calloc(num_dials, sizeof(void *)))) {
ast_log(LOG_ERROR, "Can't allocate %ld bytes for dial list\n", (sizeof(void *) * num_dials));
ast_module_user_remove(u);
return -1;
}
/* Go through parsing/calling each device */
while ((tech = strsep(&tmp, "&"))) {
struct ast_dial *dial = NULL;
/* don't call the originating device */
if (!strcasecmp(tech, originator))
continue;
/* If no resource is available, continue on */
if (!(resource = strchr(tech, '/'))) {
ast_log(LOG_WARNING, "Incomplete destination '%s' supplied.\n", tech);
continue;
}
*resource++ = '\0';
/* Create a dialing structure */
if (!(dial = ast_dial_create())) {
ast_log(LOG_WARNING, "Failed to create dialing structure.\n");
continue;
}
/* Append technology and resource */
ast_dial_append(dial, tech, resource);
/* Set ANSWER_EXEC as global option */
ast_dial_option_global_enable(dial, AST_DIAL_OPTION_ANSWER_EXEC, meetmeopts);
/* Run this dial in async mode */
ast_dial_run(dial, chan, 1);
/* Put in our dialing array */
dial_list[pos++] = dial;
}
if (!ast_test_flag(&flags, PAGE_QUIET)) {
res = ast_streamfile(chan, "beep", chan->language);
if (!res)
res = ast_waitstream(chan, "");
}
if (!res) {
snprintf(meetmeopts, sizeof(meetmeopts), "%ud|A%s%sqxd", confid, (ast_test_flag(&flags, PAGE_DUPLEX) ? "" : "t"),
(ast_test_flag(&flags, PAGE_RECORD) ? "r" : "") );
pbx_exec(chan, app, meetmeopts);
}
/* Go through each dial attempt cancelling, joining, and destroying */
for (i = 0; i < pos; i++) {
struct ast_dial *dial = dial_list[i];
/* We have to wait for the async thread to exit as it's possible Meetme won't throw them out immediately */
ast_dial_join(dial);
/* Hangup all channels */
ast_dial_hangup(dial);
/* Destroy dialing structure */
ast_dial_destroy(dial);
}
ast_free(dial_list);
ast_module_user_remove(u);
return -1;
}
static int unload_module(void)
{
int res;
res = ast_unregister_application(app_page);
ast_module_user_hangup_all();
return res;
}
static int load_module(void)
{
return ast_register_application(app_page, page_exec, page_synopsis, page_descrip);
}
AST_MODULE_INFO_STANDARD(ASTERISK_GPL_KEY, "Page Multiple Phones");