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Author SHA1 Message Date
Asterisk Autobuilder
8ed9689bbf Importing release summary for 11.7.0-rc2 release.
git-svn-id: https://origsvn.digium.com/svn/asterisk/tags/11.7.0-rc2@403984 65c4cc65-6c06-0410-ace0-fbb531ad65f3
2013-12-16 20:39:44 +00:00
Asterisk Autobuilder
e23d71a8c7 Update 11.7.0-rc2
* Merge AST-2013-006
* Merge AST-2013-007


git-svn-id: https://origsvn.digium.com/svn/asterisk/tags/11.7.0-rc2@403978 65c4cc65-6c06-0410-ace0-fbb531ad65f3
2013-12-16 19:22:01 +00:00
Asterisk Autobuilder
0e9b19501c Update version; Remove old summaries
git-svn-id: https://origsvn.digium.com/svn/asterisk/tags/11.7.0-rc2@403849 65c4cc65-6c06-0410-ace0-fbb531ad65f3
2013-12-16 15:04:54 +00:00
Asterisk Autobuilder
9a12e32c9f Create 11.7.0-rc2
git-svn-id: https://origsvn.digium.com/svn/asterisk/tags/11.7.0-rc2@403844 65c4cc65-6c06-0410-ace0-fbb531ad65f3
2013-12-16 14:54:06 +00:00
Asterisk Autobuilder
20d6fa7721 Use autotagged externals
git-svn-id: https://origsvn.digium.com/svn/asterisk/tags/11.7.0-rc1@402108 65c4cc65-6c06-0410-ace0-fbb531ad65f3
2013-10-28 14:00:55 +00:00
Asterisk Autobuilder
8cc812da87 Importing release summary for 11.7.0-rc1 release.
git-svn-id: https://origsvn.digium.com/svn/asterisk/tags/11.7.0-rc1@402107 65c4cc65-6c06-0410-ace0-fbb531ad65f3
2013-10-28 14:00:45 +00:00
Asterisk Autobuilder
552a57c680 Importing files for 11.7.0-rc1 release.
git-svn-id: https://origsvn.digium.com/svn/asterisk/tags/11.7.0-rc1@402106 65c4cc65-6c06-0410-ace0-fbb531ad65f3
2013-10-28 14:00:37 +00:00
Asterisk Autobuilder
1ee4abe7bf Creating tag for the release of asterisk-11.7.0-rc1
git-svn-id: https://origsvn.digium.com/svn/asterisk/tags/11.7.0-rc1@402105 65c4cc65-6c06-0410-ace0-fbb531ad65f3
2013-10-28 13:58:05 +00:00
18 changed files with 28294 additions and 38 deletions

1
.lastclean Normal file
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@@ -0,0 +1 @@
40

1
.version Normal file
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@@ -0,0 +1 @@
11.7.0-rc2

27642
ChangeLog Normal file

File diff suppressed because it is too large Load Diff

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@@ -26,6 +26,9 @@ Sections
* Manager Class Authorizations:
Recognizing potential issues with certain classes of authorization
* Avoid Privilege Escalations:
Disable the ability to execute functions that may escalate privileges
----------------
Additional Links
----------------
@@ -344,3 +347,24 @@ same as the class authorization "system". Good system configuration, such as
not running Asterisk as root, can prevent serious problems from arising when
allowing external connections to originate calls into Asterisk.
===========================
Avoid Privilege Escalations
===========================
External control protocols, such as Manager, often have the ability to get and
set channel variables; which allows the execution of dialplan functions.
Dialplan functions within Asterisk are incredibly powerful, which is wonderful
for building applications using Asterisk. But during the read or write
execution, certain diaplan functions do much more. For example, reading the
SHELL() function can execute arbitrary commands on the system Asterisk is
running on. Writing to the FILE() function can change any file that Asterisk has
write access to.
When these functions are executed from an external protocol, that execution
could result in a privilege escalation. Asterisk can inhibit the execution of
these functions, if live_dangerously in the [options] section of asterisk.conf
is set to no.
For backwards compatibility, live_dangerously defaults to yes, and must be
explicitly set to no to enable this privilege escalation protection.

View File

@@ -26,6 +26,14 @@ ConfBridge
conference. The language can be set on a bridge profile in confbridge.conf
or by the dialplan function CONFBRIDGE(bridge,language)=en.
* Certain dialplan functions have been marked as 'dangerous', and may only be
executed from the dialplan. Execution from extenal sources (AMI's GetVar and
SetVar actions; etc.) may be inhibited by setting live_dangerously in the
[options] section of asterisk.conf to no. SHELL(), channel locking, and direct
file read/write functions are marked as dangerous. DB_DELETE() and
REALTIME_DESTROY() are marked as dangerous for reads, but can now safely
accept writes (which ignore the provided value).
From 11.5 to 11.6:
* res_agi will now properly indicate if there was an error in streaming an
audio file. The result code will be -1 and the result returned from the

View File

@@ -696,7 +696,7 @@ static void unpacksms16(unsigned char *i, unsigned char l, unsigned char *udh, i
}
while (l--) {
int v = *i++;
if (l--) {
if (l && l--) {
v = (v << 8) + *i++;
}
*o++ = v;
@@ -714,6 +714,7 @@ static int unpacksms(unsigned char dcs, unsigned char *i, unsigned char *udh, in
} else if (is8bit(dcs)) {
unpacksms8(i, l, udh, udhl, ud, udl, udhi);
} else {
l += l % 2;
unpacksms16(i, l, udh, udhl, ud, udl, udhi);
}
return l + 1;

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@@ -0,0 +1,73 @@
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head><meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1" /><title>Release Summary - asterisk-11.7.0-rc2</title></head>
<body>
<h1 align="center"><a name="top">Release Summary</a></h1>
<h3 align="center">asterisk-11.7.0-rc2</h3>
<h3 align="center">Date: 2013-12-16</h3>
<h3 align="center">&lt;asteriskteam@digium.com&gt;</h3>
<hr/>
<h2 align="center">Table of Contents</h2>
<ol>
<li><a href="#summary">Summary</a></li>
<li><a href="#contributors">Contributors</a></li>
<li><a href="#commits">Other Changes</a></li>
<li><a href="#diffstat">Diffstat</a></li>
</ol>
<hr/>
<a name="summary"><h2 align="center">Summary</h2></a>
<center><a href="#top">[Back to Top]</a></center><br/><p>This release includes only bug fixes. The changes included were made only to address problems that have been identified in this release series. Users should be able to safely upgrade to this version if this release series is already in use. Users considering upgrading from a previous release series are strongly encouraged to review the UPGRADE.txt document as well as the CHANGES document for information about upgrading to this release series.</p>
<p>The data in this summary reflects changes that have been made since the previous release, asterisk-11.7.0-rc1.</p>
<hr/>
<a name="contributors"><h2 align="center">Contributors</h2></a>
<center><a href="#top">[Back to Top]</a></center><br/><p>This table lists the people who have submitted code, those that have tested patches, as well as those that reported issues on the issue tracker that were resolved in this release. For coders, the number is how many of their patches (of any size) were committed into this release. For testers, the number is the number of times their name was listed as assisting with testing a patch. Finally, for reporters, the number is the number of issues that they reported that were closed by commits that went into this release.</p>
<table width="100%" border="0">
<tr>
<td width="33%"><h3>Coders</h3></td>
<td width="33%"><h3>Testers</h3></td>
<td width="33%"><h3>Reporters</h3></td>
</tr>
<tr valign="top">
<td>
3 bebuild<br/>
</td>
<td>
</td>
<td>
</td>
</tr>
</table>
<hr/>
<a name="commits"><h2 align="center">Commits Not Associated with an Issue</h2></a>
<center><a href="#top">[Back to Top]</a></center><br/><p>This is a list of all changes that went into this release that did not directly close an issue from the issue tracker. The commits may have been marked as being related to an issue. If that is the case, the issue numbers are listed here, as well.</p>
<table width="100%" border="1">
<tr><td><b>Revision</b></td><td><b>Author</b></td><td><b>Summary</b></td><td><b>Issues Referenced</b></td></tr><tr><td><a href="http://svn.digium.com/view/asterisk/branches/11?view=revision&revision=403844">403844</a></td><td>bebuild</td><td>Create 11.7.0-rc2</td>
<td></td></tr><tr><td><a href="http://svn.digium.com/view/asterisk/branches/11?view=revision&revision=403849">403849</a></td><td>bebuild</td><td>Update version; Remove old summaries</td>
<td></td></tr><tr><td><a href="http://svn.digium.com/view/asterisk/branches/11?view=revision&revision=403978">403978</a></td><td>bebuild</td><td>Update 11.7.0-rc2</td>
<td></td></tr></table>
<hr/>
<a name="diffstat"><h2 align="center">Diffstat Results</h2></a>
<center><a href="#top">[Back to Top]</a></center><br/><p>This is a summary of the changes to the source code that went into this release that was generated using the diffstat utility.</p>
<pre>
.version | 2
ChangeLog | 29 +
README-SERIOUSLY.bestpractices.txt | 24 +
UPGRADE.txt | 8
apps/app_sms.c | 3
asterisk-11.7.0-rc1-summary.html | 437 -----------------------------
asterisk-11.7.0-rc1-summary.txt | 544 -------------------------------------
configs/asterisk.conf.sample | 6
funcs/func_db.c | 20 +
funcs/func_env.c | 28 +
funcs/func_lock.c | 21 +
funcs/func_realtime.c | 60 ++--
funcs/func_shell.c | 18 -
include/asterisk/pbx.h | 54 +++
main/asterisk.c | 5
main/pbx.c | 254 +++++++++++++++++
main/tcptls.c | 11
17 files changed, 504 insertions(+), 1020 deletions(-)
</pre><br/>
<hr/>
</body>
</html>

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@@ -0,0 +1,103 @@
Release Summary
asterisk-11.7.0-rc2
Date: 2013-12-16
<asteriskteam@digium.com>
----------------------------------------------------------------------
Table of Contents
1. Summary
2. Contributors
3. Other Changes
4. Diffstat
----------------------------------------------------------------------
Summary
[Back to Top]
This release includes only bug fixes. The changes included were made only
to address problems that have been identified in this release series.
Users should be able to safely upgrade to this version if this release
series is already in use. Users considering upgrading from a previous
release series are strongly encouraged to review the UPGRADE.txt document
as well as the CHANGES document for information about upgrading to this
release series.
The data in this summary reflects changes that have been made since the
previous release, asterisk-11.7.0-rc1.
----------------------------------------------------------------------
Contributors
[Back to Top]
This table lists the people who have submitted code, those that have
tested patches, as well as those that reported issues on the issue tracker
that were resolved in this release. For coders, the number is how many of
their patches (of any size) were committed into this release. For testers,
the number is the number of times their name was listed as assisting with
testing a patch. Finally, for reporters, the number is the number of
issues that they reported that were closed by commits that went into this
release.
Coders Testers Reporters
3 bebuild
----------------------------------------------------------------------
Commits Not Associated with an Issue
[Back to Top]
This is a list of all changes that went into this release that did not
directly close an issue from the issue tracker. The commits may have been
marked as being related to an issue. If that is the case, the issue
numbers are listed here, as well.
+------------------------------------------------------------------------+
| Revision | Author | Summary | Issues Referenced |
|----------+---------+-------------------------------+-------------------|
| 403844 | bebuild | Create 11.7.0-rc2 | |
|----------+---------+-------------------------------+-------------------|
| 403849 | bebuild | Update version; Remove old | |
| | | summaries | |
|----------+---------+-------------------------------+-------------------|
| 403978 | bebuild | Update 11.7.0-rc2 | |
+------------------------------------------------------------------------+
----------------------------------------------------------------------
Diffstat Results
[Back to Top]
This is a summary of the changes to the source code that went into this
release that was generated using the diffstat utility.
.version | 2
ChangeLog | 29 +
README-SERIOUSLY.bestpractices.txt | 24 +
UPGRADE.txt | 8
apps/app_sms.c | 3
asterisk-11.7.0-rc1-summary.html | 437 -----------------------------
asterisk-11.7.0-rc1-summary.txt | 544 -------------------------------------
configs/asterisk.conf.sample | 6
funcs/func_db.c | 20 +
funcs/func_env.c | 28 +
funcs/func_lock.c | 21 +
funcs/func_realtime.c | 60 ++--
funcs/func_shell.c | 18 -
include/asterisk/pbx.h | 54 +++
main/asterisk.c | 5
main/pbx.c | 254 +++++++++++++++++
main/tcptls.c | 11
17 files changed, 504 insertions(+), 1020 deletions(-)
----------------------------------------------------------------------

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@@ -83,6 +83,12 @@ documentation_language = en_US ; Set the language you want documentation
; gosub - Invoke the stdexten using a gosub as
; documented in extensions.conf.sample.
; Default gosub.
;live_dangerously = no ; Enable the execution of 'dangerous' dialplan
; functions from external sources (AMI,
; etc.) These functions (such as SHELL) are
; considered dangerous because they can allow
; privilege escalation.
; Default yes, for backward compatability.
; Changing the following lines may compromise your security.
;[files]

View File

@@ -110,6 +110,12 @@ ASTERISK_FILE_VERSION(__FILE__, "$Revision$")
<para>This function will retrieve a value from the Asterisk database
and then remove that key from the database. <variable>DB_RESULT</variable>
will be set to the key's value if it exists.</para>
<note>
<para>If <literal>live_dangerously</literal> in <literal>asterisk.conf</literal>
is set to <literal>no</literal>, this function can only be read from the
dialplan, and not directly from external protocols. It can, however, be
executed as a write operation (<literal>DB_DELETE(family, key)=ignored</literal>)</para>
</note>
</description>
<see-also>
<ref type="application">DBdel</ref>
@@ -311,10 +317,22 @@ static int function_db_delete(struct ast_channel *chan, const char *cmd,
return 0;
}
/*!
* \brief Wrapper to execute DB_DELETE from a write operation. Allows execution
* even if live_dangerously is disabled.
*/
static int function_db_delete_write(struct ast_channel *chan, const char *cmd, char *parse,
const char *value)
{
/* Throwaway to hold the result from the read */
char buf[128];
return function_db_delete(chan, cmd, parse, buf, sizeof(buf));
}
static struct ast_custom_function db_delete_function = {
.name = "DB_DELETE",
.read = function_db_delete,
.write = function_db_delete_write,
};
static int unload_module(void)
@@ -335,7 +353,7 @@ static int load_module(void)
res |= ast_custom_function_register(&db_function);
res |= ast_custom_function_register(&db_exists_function);
res |= ast_custom_function_register(&db_delete_function);
res |= ast_custom_function_register_escalating(&db_delete_function, AST_CFE_READ);
res |= ast_custom_function_register(&db_keys_function);
return res;

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@@ -71,6 +71,11 @@ ASTERISK_FILE_VERSION(__FILE__, "$Revision$")
<parameter name="filename" required="true" />
</syntax>
<description>
<note>
<para>If <literal>live_dangerously</literal> in <literal>asterisk.conf</literal>
is set to <literal>no</literal>, this function can only be executed from the
dialplan, and not directly from external protocols.</para>
</note>
</description>
</function>
<function name="FILE" language="en_US">
@@ -167,6 +172,11 @@ ASTERISK_FILE_VERSION(__FILE__, "$Revision$")
<para> Set(FILE(/tmp/foo.txt,-1,,l)=bar)</para>
<para> ; Append "bar" to the file with a newline</para>
<para> Set(FILE(/tmp/foo.txt,,,al)=bar)</para>
<note>
<para>If <literal>live_dangerously</literal> in <literal>asterisk.conf</literal>
is set to <literal>no</literal>, this function can only be executed from the
dialplan, and not directly from external protocols.</para>
</note>
</description>
<see-also>
<ref type="function">FILE_COUNT_LINE</ref>
@@ -197,6 +207,11 @@ ASTERISK_FILE_VERSION(__FILE__, "$Revision$")
</syntax>
<description>
<para>Returns the number of lines, or <literal>-1</literal> on error.</para>
<note>
<para>If <literal>live_dangerously</literal> in <literal>asterisk.conf</literal>
is set to <literal>no</literal>, this function can only be executed from the
dialplan, and not directly from external protocols.</para>
</note>
</description>
<see-also>
<ref type="function">FILE</ref>
@@ -216,6 +231,11 @@ ASTERISK_FILE_VERSION(__FILE__, "$Revision$")
<para>'d' - DOS "\r\n" format</para>
<para>'m' - Macintosh "\r" format</para>
<para>'x' - Cannot be determined</para>
<note>
<para>If <literal>live_dangerously</literal> in <literal>asterisk.conf</literal>
is set to <literal>no</literal>, this function can only be executed from the
dialplan, and not directly from external protocols.</para>
</note>
</description>
<see-also>
<ref type="function">FILE</ref>
@@ -1259,10 +1279,10 @@ static int load_module(void)
int res = 0;
res |= ast_custom_function_register(&env_function);
res |= ast_custom_function_register(&stat_function);
res |= ast_custom_function_register(&file_function);
res |= ast_custom_function_register(&file_count_line_function);
res |= ast_custom_function_register(&file_format_function);
res |= ast_custom_function_register_escalating(&stat_function, AST_CFE_READ);
res |= ast_custom_function_register_escalating(&file_function, AST_CFE_BOTH);
res |= ast_custom_function_register_escalating(&file_count_line_function, AST_CFE_READ);
res |= ast_custom_function_register_escalating(&file_format_function, AST_CFE_READ);
return res;
}

View File

@@ -59,6 +59,11 @@ ASTERISK_FILE_VERSION(__FILE__, "$Revision$")
Returns <literal>1</literal> if the lock was obtained or <literal>0</literal> on error.</para>
<note><para>To avoid the possibility of a deadlock, LOCK will only attempt to
obtain the lock for 3 seconds if the channel already has another lock.</para></note>
<note>
<para>If <literal>live_dangerously</literal> in <literal>asterisk.conf</literal>
is set to <literal>no</literal>, this function can only be executed from the
dialplan, and not directly from external protocols.</para>
</note>
</description>
</function>
<function name="TRYLOCK" language="en_US">
@@ -72,6 +77,11 @@ ASTERISK_FILE_VERSION(__FILE__, "$Revision$")
<para>Attempts to grab a named lock exclusively, and prevents other channels
from obtaining the same lock. Returns <literal>1</literal> if the lock was
available or <literal>0</literal> otherwise.</para>
<note>
<para>If <literal>live_dangerously</literal> in <literal>asterisk.conf</literal>
is set to <literal>no</literal>, this function can only be executed from the
dialplan, and not directly from external protocols.</para>
</note>
</description>
</function>
<function name="UNLOCK" language="en_US">
@@ -86,6 +96,11 @@ ASTERISK_FILE_VERSION(__FILE__, "$Revision$")
had a lock or <literal>0</literal> otherwise.</para>
<note><para>It is generally unnecessary to unlock in a hangup routine, as any locks
held are automatically freed when the channel is destroyed.</para></note>
<note>
<para>If <literal>live_dangerously</literal> in <literal>asterisk.conf</literal>
is set to <literal>no</literal>, this function can only be executed from the
dialplan, and not directly from external protocols.</para>
</note>
</description>
</function>
***/
@@ -502,9 +517,9 @@ static int unload_module(void)
static int load_module(void)
{
int res = ast_custom_function_register(&lock_function);
res |= ast_custom_function_register(&trylock_function);
res |= ast_custom_function_register(&unlock_function);
int res = ast_custom_function_register_escalating(&lock_function, AST_CFE_READ);
res |= ast_custom_function_register_escalating(&trylock_function, AST_CFE_READ);
res |= ast_custom_function_register_escalating(&unlock_function, AST_CFE_READ);
if (ast_pthread_create_background(&broker_tid, NULL, lock_broker, NULL)) {
ast_log(LOG_ERROR, "Failed to start lock broker thread. Unloading func_lock module.\n");

View File

@@ -115,6 +115,12 @@ ASTERISK_FILE_VERSION(__FILE__, "$Revision$")
<description>
<para>This function acts in the same way as REALTIME(....) does, except that
it destroys the matched record in the RT engine.</para>
<note>
<para>If <literal>live_dangerously</literal> in <literal>asterisk.conf</literal>
is set to <literal>no</literal>, this function can only be read from the
dialplan, and not directly from external protocols. It can, however, be
executed as a write operation (<literal>REALTIME_DESTROY(family, fieldmatch)=ignored</literal>)</para>
</note>
</description>
<see-also>
<ref type="function">REALTIME</ref>
@@ -439,28 +445,32 @@ static int function_realtime_readdestroy(struct ast_channel *chan, const char *c
return -1;
}
resultslen = 0;
n = 0;
for (var = head; var; n++, var = var->next)
resultslen += strlen(var->name) + strlen(var->value);
/* add space for delimiters and final '\0' */
resultslen += n * (strlen(args.delim1) + strlen(args.delim2)) + 1;
if (len > 0) {
resultslen = 0;
n = 0;
for (var = head; var; n++, var = var->next) {
resultslen += strlen(var->name) + strlen(var->value);
}
/* add space for delimiters and final '\0' */
resultslen += n * (strlen(args.delim1) + strlen(args.delim2)) + 1;
if (resultslen > len) {
/* Unfortunately this does mean that we cannot destroy the row
* anymore. But OTOH, we're not destroying someones data without
* giving him the chance to look at it. */
ast_log(LOG_WARNING, "Failed to fetch/destroy. Realtime data is too large: need %zu, have %zu.\n", resultslen, len);
return -1;
}
if (resultslen > len) {
/* Unfortunately this does mean that we cannot destroy
* the row anymore. But OTOH, we're not destroying
* someones data without giving him the chance to look
* at it. */
ast_log(LOG_WARNING, "Failed to fetch/destroy. Realtime data is too large: need %zu, have %zu.\n", resultslen, len);
return -1;
}
/* len is going to be sensible, so we don't need to check for stack
* overflows here. */
out = ast_str_alloca(resultslen);
for (var = head; var; var = var->next) {
ast_str_append(&out, 0, "%s%s%s%s", var->name, args.delim2, var->value, args.delim1);
/* len is going to be sensible, so we don't need to check for
* stack overflows here. */
out = ast_str_alloca(resultslen);
for (var = head; var; var = var->next) {
ast_str_append(&out, 0, "%s%s%s%s", var->name, args.delim2, var->value, args.delim1);
}
ast_copy_string(buf, ast_str_buffer(out), len);
}
ast_copy_string(buf, ast_str_buffer(out), len);
ast_destroy_realtime(args.family, args.fieldmatch, args.value, SENTINEL);
ast_variables_destroy(head);
@@ -471,6 +481,15 @@ static int function_realtime_readdestroy(struct ast_channel *chan, const char *c
return 0;
}
/*!
* \brief Wrapper to execute REALTIME_DESTROY from a write operation. Allows
* execution even if live_dangerously is disabled.
*/
static int function_realtime_writedestroy(struct ast_channel *chan, const char *cmd, char *data, const char *value)
{
return function_realtime_readdestroy(chan, cmd, data, NULL, 0);
}
static struct ast_custom_function realtime_function = {
.name = "REALTIME",
.read = function_realtime_read,
@@ -496,6 +515,7 @@ static struct ast_custom_function realtime_store_function = {
static struct ast_custom_function realtime_destroy_function = {
.name = "REALTIME_DESTROY",
.read = function_realtime_readdestroy,
.write = function_realtime_writedestroy,
};
static int unload_module(void)
@@ -514,7 +534,7 @@ static int load_module(void)
int res = 0;
res |= ast_custom_function_register(&realtime_function);
res |= ast_custom_function_register(&realtime_store_function);
res |= ast_custom_function_register(&realtime_destroy_function);
res |= ast_custom_function_register_escalating(&realtime_destroy_function, AST_CFE_READ);
res |= ast_custom_function_register(&realtimefield_function);
res |= ast_custom_function_register(&realtimehash_function);
return res;

View File

@@ -88,11 +88,17 @@ static int shell_helper(struct ast_channel *chan, const char *cmd, char *data,
</syntax>
<description>
<para>Collects the output generated by a command executed by the system shell</para>
<para>Example: <literal>Set(foo=${SHELL(echo \bar\)})</literal></para>
<note><para>The command supplied to this function will be executed by the
system's shell, typically specified in the SHELL environment variable. There
are many different system shells available with somewhat different behaviors,
so the output generated by this function may vary between platforms.</para></note>
<para>Example: <literal>Set(foo=${SHELL(echo bar)})</literal></para>
<note>
<para>The command supplied to this function will be executed by the
system's shell, typically specified in the SHELL environment variable. There
are many different system shells available with somewhat different behaviors,
so the output generated by this function may vary between platforms.</para>
<para>If <literal>live_dangerously</literal> in <literal>asterisk.conf</literal>
is set to <literal>no</literal>, this function can only be executed from the
dialplan, and not directly from external protocols.</para>
</note>
</description>
</function>
@@ -109,7 +115,7 @@ static int unload_module(void)
static int load_module(void)
{
return ast_custom_function_register(&shell_function);
return ast_custom_function_register_escalating(&shell_function, AST_CFE_READ);
}
AST_MODULE_INFO_STANDARD(ASTERISK_GPL_KEY, "Collects the output generated by a command executed by the system shell");

View File

@@ -1309,16 +1309,44 @@ struct ast_custom_function* ast_custom_function_find(const char *name);
*/
int ast_custom_function_unregister(struct ast_custom_function *acf);
/*!
* \brief Description of the ways in which a function may escalate privileges.
*/
enum ast_custom_function_escalation {
AST_CFE_NONE,
AST_CFE_READ,
AST_CFE_WRITE,
AST_CFE_BOTH,
};
/*!
* \brief Register a custom function
*/
#define ast_custom_function_register(acf) __ast_custom_function_register(acf, ast_module_info->self)
/*!
* \brief Register a custom function which requires escalated privileges.
*
* Examples would be SHELL() (for which a read needs permission to execute
* arbitrary code) or FILE() (for which write needs permission to change files
* on the filesystem).
*/
#define ast_custom_function_register_escalating(acf, escalation) __ast_custom_function_register_escalating(acf, escalation, ast_module_info->self)
/*!
* \brief Register a custom function
*/
int __ast_custom_function_register(struct ast_custom_function *acf, struct ast_module *mod);
/*!
* \brief Register a custom function which requires escalated privileges.
*
* Examples would be SHELL() (for which a read needs permission to execute
* arbitrary code) or FILE() (for which write needs permission to change files
* on the filesystem).
*/
int __ast_custom_function_register_escalating(struct ast_custom_function *acf, enum ast_custom_function_escalation escalation, struct ast_module *mod);
/*!
* \brief Retrieve the number of active calls
*/
@@ -1432,6 +1460,32 @@ unsigned int ast_hashtab_hash_contexts(const void *obj);
*/
char *ast_complete_applications(const char *line, const char *word, int state);
/*!
* \brief Enable/disable the execution of 'dangerous' functions from external
* protocols (AMI, etc.).
*
* These dialplan functions (such as \c SHELL) provide an opportunity for
* privilege escalation. They are okay to invoke from the dialplan, but external
* protocols with permission controls should not normally invoke them.
*
* This function can globally enable/disable the execution of dangerous
* functions from external protocols.
*
* \param new_live_dangerously If true, enable the execution of escalating
* functions from external protocols.
*/
void pbx_live_dangerously(int new_live_dangerously);
/*!
* \brief Inhibit (in the current thread) the execution of dialplan functions
* which cause privilege escalations. If pbx_live_dangerously() has been
* called, this function has no effect.
*
* \return 0 if successfuly marked current thread.
* \return Non-zero if marking current thread failed.
*/
int ast_thread_inhibit_escalations(void);
#if defined(__cplusplus) || defined(c_plusplus)
}
#endif

View File

@@ -3184,6 +3184,8 @@ static void ast_readconfig(void)
unsigned int dbdir:1;
unsigned int keydir:1;
} found = { 0, 0 };
/* Default to true for backward compatibility */
int live_dangerously = 1;
/* Set default value */
option_dtmfminduration = AST_MIN_DTMF_DURATION;
@@ -3415,8 +3417,11 @@ static void ast_readconfig(void)
v->value);
ast_clear_flag(&ast_options, AST_OPT_FLAG_STDEXTEN_MACRO);
}
} else if (!strcasecmp(v->name, "live_dangerously")) {
live_dangerously = ast_true(v->value);
}
}
pbx_live_dangerously(live_dangerously);
for (v = ast_variable_browse(cfg, "compat"); v; v = v->next) {
float version;
if (sscanf(v->value, "%30f", &version) != 1) {

View File

@@ -822,6 +822,17 @@ static struct ast_taskprocessor *extension_state_tps;
AST_THREADSTORAGE(switch_data);
AST_THREADSTORAGE(extensionstate_buf);
/*!
* \brief A thread local indicating whether the current thread can run
* 'dangerous' dialplan functions.
*/
AST_THREADSTORAGE(thread_inhibit_escalations_tl);
/*!
* \brief Set to true (non-zero) to globally allow all dangerous dialplan
* functions to run.
*/
static int live_dangerously;
/*!
\brief ast_exten: An extension
@@ -1318,6 +1329,19 @@ static int totalcalls;
static AST_RWLIST_HEAD_STATIC(acf_root, ast_custom_function);
/*!
* \brief Extra information for an \ref ast_custom_function holding privilege
* escalation information. Kept in a separate structure for ABI compatibility.
*/
struct ast_custom_escalating_function {
AST_RWLIST_ENTRY(ast_custom_escalating_function) list;
const struct ast_custom_function *acf;
unsigned int read_escalates:1;
unsigned int write_escalates:1;
};
static AST_RWLIST_HEAD_STATIC(escalation_root, ast_custom_escalating_function);
/*! \brief Declaration of builtin applications */
static struct pbx_builtin {
char name[AST_MAX_APP];
@@ -3911,6 +3935,7 @@ struct ast_custom_function *ast_custom_function_find(const char *name)
int ast_custom_function_unregister(struct ast_custom_function *acf)
{
struct ast_custom_function *cur;
struct ast_custom_escalating_function *cur_escalation;
if (!acf) {
return -1;
@@ -3927,9 +3952,64 @@ int ast_custom_function_unregister(struct ast_custom_function *acf)
}
AST_RWLIST_UNLOCK(&acf_root);
/* Remove from the escalation list */
AST_RWLIST_WRLOCK(&escalation_root);
AST_RWLIST_TRAVERSE_SAFE_BEGIN(&escalation_root, cur_escalation, list) {
if (cur_escalation->acf == acf) {
AST_RWLIST_REMOVE_CURRENT(list);
break;
}
}
AST_RWLIST_TRAVERSE_SAFE_END;
AST_RWLIST_UNLOCK(&escalation_root);
return cur ? 0 : -1;
}
/*!
* \brief Returns true if given custom function escalates privileges on read.
*
* \param acf Custom function to query.
* \return True (non-zero) if reads escalate privileges.
* \return False (zero) if reads just read.
*/
static int read_escalates(const struct ast_custom_function *acf) {
int res = 0;
struct ast_custom_escalating_function *cur_escalation;
AST_RWLIST_RDLOCK(&escalation_root);
AST_RWLIST_TRAVERSE(&escalation_root, cur_escalation, list) {
if (cur_escalation->acf == acf) {
res = cur_escalation->read_escalates;
break;
}
}
AST_RWLIST_UNLOCK(&escalation_root);
return res;
}
/*!
* \brief Returns true if given custom function escalates privileges on write.
*
* \param acf Custom function to query.
* \return True (non-zero) if writes escalate privileges.
* \return False (zero) if writes just write.
*/
static int write_escalates(const struct ast_custom_function *acf) {
int res = 0;
struct ast_custom_escalating_function *cur_escalation;
AST_RWLIST_RDLOCK(&escalation_root);
AST_RWLIST_TRAVERSE(&escalation_root, cur_escalation, list) {
if (cur_escalation->acf == acf) {
res = cur_escalation->write_escalates;
break;
}
}
AST_RWLIST_UNLOCK(&escalation_root);
return res;
}
/*! \internal
* \brief Retrieve the XML documentation of a specified ast_custom_function,
* and populate ast_custom_function string fields.
@@ -4031,6 +4111,50 @@ int __ast_custom_function_register(struct ast_custom_function *acf, struct ast_m
return 0;
}
int __ast_custom_function_register_escalating(struct ast_custom_function *acf, enum ast_custom_function_escalation escalation, struct ast_module *mod)
{
struct ast_custom_escalating_function *acf_escalation = NULL;
int res;
res = __ast_custom_function_register(acf, mod);
if (res != 0) {
return -1;
}
if (escalation == AST_CFE_NONE) {
/* No escalations; no need to do anything else */
return 0;
}
acf_escalation = ast_calloc(1, sizeof(*acf_escalation));
if (!acf_escalation) {
ast_custom_function_unregister(acf);
return -1;
}
acf_escalation->acf = acf;
switch (escalation) {
case AST_CFE_NONE:
break;
case AST_CFE_READ:
acf_escalation->read_escalates = 1;
break;
case AST_CFE_WRITE:
acf_escalation->write_escalates = 1;
break;
case AST_CFE_BOTH:
acf_escalation->read_escalates = 1;
acf_escalation->write_escalates = 1;
break;
}
AST_RWLIST_WRLOCK(&escalation_root);
AST_RWLIST_INSERT_TAIL(&escalation_root, acf_escalation, list);
AST_RWLIST_UNLOCK(&escalation_root);
return 0;
}
/*! \brief return a pointer to the arguments of the function,
* and terminates the function name with '\\0'
*/
@@ -4052,6 +4176,124 @@ static char *func_args(char *function)
return args;
}
void pbx_live_dangerously(int new_live_dangerously)
{
if (new_live_dangerously && !live_dangerously) {
ast_log(LOG_WARNING, "Privilege escalation protection disabled!\n"
"See https://wiki.asterisk.org/wiki/x/1gKfAQ for more details.\n");
}
if (!new_live_dangerously && live_dangerously) {
ast_log(LOG_NOTICE, "Privilege escalation protection enabled.\n");
}
live_dangerously = new_live_dangerously;
}
int ast_thread_inhibit_escalations(void)
{
int *thread_inhibit_escalations;
thread_inhibit_escalations = ast_threadstorage_get(
&thread_inhibit_escalations_tl, sizeof(*thread_inhibit_escalations));
if (thread_inhibit_escalations == NULL) {
ast_log(LOG_ERROR, "Error inhibiting privilege escalations for current thread\n");
return -1;
}
*thread_inhibit_escalations = 1;
return 0;
}
/*!
* \brief Indicates whether the current thread inhibits the execution of
* dangerous functions.
*
* \return True (non-zero) if dangerous function execution is inhibited.
* \return False (zero) if dangerous function execution is allowed.
*/
static int thread_inhibits_escalations(void)
{
int *thread_inhibit_escalations;
thread_inhibit_escalations = ast_threadstorage_get(
&thread_inhibit_escalations_tl, sizeof(*thread_inhibit_escalations));
if (thread_inhibit_escalations == NULL) {
ast_log(LOG_ERROR, "Error checking thread's ability to run dangerous functions\n");
/* On error, assume that we are inhibiting */
return 1;
}
return *thread_inhibit_escalations;
}
/*!
* \brief Determines whether execution of a custom function's read function
* is allowed.
*
* \param acfptr Custom function to check
* \return True (non-zero) if reading is allowed.
* \return False (zero) if reading is not allowed.
*/
static int is_read_allowed(struct ast_custom_function *acfptr)
{
if (!acfptr) {
return 1;
}
if (!read_escalates(acfptr)) {
return 1;
}
if (!thread_inhibits_escalations()) {
return 1;
}
if (live_dangerously) {
/* Global setting overrides the thread's preference */
ast_debug(2, "Reading %s from a dangerous context\n",
acfptr->name);
return 1;
}
/* We have no reason to allow this function to execute */
return 0;
}
/*!
* \brief Determines whether execution of a custom function's write function
* is allowed.
*
* \param acfptr Custom function to check
* \return True (non-zero) if writing is allowed.
* \return False (zero) if writing is not allowed.
*/
static int is_write_allowed(struct ast_custom_function *acfptr)
{
if (!acfptr) {
return 1;
}
if (!write_escalates(acfptr)) {
return 1;
}
if (!thread_inhibits_escalations()) {
return 1;
}
if (live_dangerously) {
/* Global setting overrides the thread's preference */
ast_debug(2, "Writing %s from a dangerous context\n",
acfptr->name);
return 1;
}
/* We have no reason to allow this function to execute */
return 0;
}
int ast_func_read(struct ast_channel *chan, const char *function, char *workspace, size_t len)
{
char *copy = ast_strdupa(function);
@@ -4064,6 +4306,8 @@ int ast_func_read(struct ast_channel *chan, const char *function, char *workspac
ast_log(LOG_ERROR, "Function %s not registered\n", copy);
} else if (!acfptr->read && !acfptr->read2) {
ast_log(LOG_ERROR, "Function %s cannot be read\n", copy);
} else if (!is_read_allowed(acfptr)) {
ast_log(LOG_ERROR, "Dangerous function %s read blocked\n", copy);
} else if (acfptr->read) {
if (acfptr->mod) {
u = __ast_module_user_add(acfptr->mod, chan);
@@ -4101,6 +4345,8 @@ int ast_func_read2(struct ast_channel *chan, const char *function, struct ast_st
ast_log(LOG_ERROR, "Function %s not registered\n", copy);
} else if (!acfptr->read && !acfptr->read2) {
ast_log(LOG_ERROR, "Function %s cannot be read\n", copy);
} else if (!is_read_allowed(acfptr)) {
ast_log(LOG_ERROR, "Dangerous function %s read blocked\n", copy);
} else {
if (acfptr->mod) {
u = __ast_module_user_add(acfptr->mod, chan);
@@ -4140,11 +4386,13 @@ int ast_func_write(struct ast_channel *chan, const char *function, const char *v
char *args = func_args(copy);
struct ast_custom_function *acfptr = ast_custom_function_find(copy);
if (acfptr == NULL)
if (acfptr == NULL) {
ast_log(LOG_ERROR, "Function %s not registered\n", copy);
else if (!acfptr->write)
} else if (!acfptr->write) {
ast_log(LOG_ERROR, "Function %s cannot be written to\n", copy);
else {
} else if (!is_write_allowed(acfptr)) {
ast_log(LOG_ERROR, "Dangerous function %s write blocked\n", copy);
} else {
int res;
struct ast_module_user *u = NULL;
if (acfptr->mod)

View File

@@ -48,6 +48,7 @@ ASTERISK_FILE_VERSION(__FILE__, "$Revision$")
#include "asterisk/options.h"
#include "asterisk/manager.h"
#include "asterisk/astobj2.h"
#include "asterisk/pbx.h"
/*! \brief
* replacement read/write functions for SSL support.
@@ -164,6 +165,16 @@ static void *handle_tcptls_connection(void *data)
char err[256];
#endif
/* TCP/TLS connections are associated with external protocols, and
* should not be allowed to execute 'dangerous' functions. This may
* need to be pushed down into the individual protocol handlers, but
* this seems like a good general policy.
*/
if (ast_thread_inhibit_escalations()) {
ast_log(LOG_ERROR, "Failed to inhibit privilege escalations; killing connection\n");
return NULL;
}
/*
* open a FILE * as appropriate.
*/