asterisk/funcs/func_shell.c
Richard Mudgett e12184cf95 Merged revisions 331576 via svnmerge from
https://origsvn.digium.com/svn/asterisk/branches/10

................
  r331576 | rmudgett | 2011-08-11 16:42:21 -0500 (Thu, 11 Aug 2011) | 16 lines
  
  Merged revisions 331575 via svnmerge from 
  https://origsvn.digium.com/svn/asterisk/branches/1.8
  
  ........
    r331575 | rmudgett | 2011-08-11 16:39:58 -0500 (Thu, 11 Aug 2011) | 9 lines
    
    Segfault in shell_helper in func_shell.c.
    
    The return value of popen() was not checked for failure to open.
    
    (closes issue ASTERISK-18109)
    JIRA SWP-3633
    Reported by: Michael Myles
    Tested by: rmudgett
  ........
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git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@331577 65c4cc65-6c06-0410-ace0-fbb531ad65f3
2011-08-11 21:44:08 +00:00

118 lines
2.9 KiB
C

/*
* Asterisk -- An open source telephony toolkit.
*
* Copyright (C) 2006, Digium, Inc.
*
* 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.
*
* This program is free software, distributed under the terms of
* the GNU General Public License Version 2. See the LICENSE file
* at the top of the source tree.
*/
/*! \file
*
* SHELL function to return the value of a system call.
*
* \note Inspiration and Guidance from Russell! Thank You!
*
* \author Brandon Kruse <bkruse@digium.com>
*
* \ingroup functions
*/
/*** MODULEINFO
<support_level>core</support_level>
***/
#include "asterisk.h"
ASTERISK_FILE_VERSION(__FILE__, "$Revision$")
#include "asterisk/module.h"
#include "asterisk/channel.h"
#include "asterisk/pbx.h"
#include "asterisk/utils.h"
#include "asterisk/app.h"
static int shell_helper(struct ast_channel *chan, const char *cmd, char *data,
char *buf, size_t len)
{
int res = 0;
if (ast_strlen_zero(data)) {
ast_log(LOG_WARNING, "Missing Argument! Example: Set(foo=${SHELL(echo \"bar\")})\n");
return -1;
}
if (chan) {
ast_autoservice_start(chan);
}
if (len >= 1) {
FILE *ptr;
char plbuff[4096];
ptr = popen(data, "r");
if (ptr) {
while (fgets(plbuff, sizeof(plbuff), ptr)) {
strncat(buf, plbuff, len - strlen(buf) - 1);
}
pclose(ptr);
} else {
ast_log(LOG_WARNING, "Failed to execute shell command '%s'\n", data);
res = -1;
}
}
if (chan) {
ast_autoservice_stop(chan);
}
return res;
}
/*** DOCUMENTATION
<function name="SHELL" language="en_US">
<synopsis>
Executes a command as if you were at a shell.
</synopsis>
<syntax>
<parameter name="command" required="true">
<para>This is the argument to the function, the command you want to pass to the shell.</para>
</parameter>
</syntax>
<description>
<para>Returns the value from a system command</para>
<para>Example: <literal>Set(foo=${SHELL(echo \bar\)})</literal></para>
<note><para>When using the SHELL() dialplan function, your \SHELL\ is /bin/sh,
which may differ as to the underlying shell, depending upon your production
platform. Also keep in mind that if you are using a common path, you should
be mindful of race conditions that could result from two calls running
SHELL() simultaneously.</para></note>
</description>
</function>
***/
static struct ast_custom_function shell_function = {
.name = "SHELL",
.read = shell_helper,
};
static int unload_module(void)
{
return ast_custom_function_unregister(&shell_function);
}
static int load_module(void)
{
return ast_custom_function_register(&shell_function);
}
AST_MODULE_INFO_STANDARD(ASTERISK_GPL_KEY, "Returns the output of a shell command");