Commit Graph

3522 Commits

Author SHA1 Message Date
Niklas Larsson
9a09f7dd5d app_queue: Add priority to AMI QueueStatus
Add priority to callers in AMI QueueStatus response

ASTERISK-27092 #close

Change-Id: I8d1f737a72c7c38f4cfe1a4ee3ecc0a4f85bd199
2017-08-01 15:44:30 -06:00
Joshua Colp
114602f434 res_pjsip: Add support for dnsmgr to external_media_address.
The "external_media_address" option on transports is now
resolved using dnsmgr. This allows it to be automatically
refreshed regularly if refreshes are enabled in dnsmgr.
If the system is using a dynamic IP address a dynamic DNS
hostname can be provided to keep the IP address up to
date.

Change-Id: Ia54771720dff0105bde55d5bbb81a3ba437e05b2
2017-08-01 15:44:30 -06:00
Torrey Searle
423d01cf16 chan_pjsip: add a new function PJSIP_DTMF_MODE
This function is a replica of SIPDtmfMode, allowing the DTMF mode of a
PJSIP call to be modified on a per-call basis

ASTERISK-27085 #close

Change-Id: I20eef5da3e5d1d3e58b304416bc79683f87e7612
2017-08-01 15:43:51 -06:00
Joshua Colp
24bb5a8908 core: Add VP9 passthrough support.
This change adds VP9 as a known codec and creates a cached
"vp9" media format for use.

Change-Id: I025a93ed05cf96153d66f36db1839109cc24c5cc
2017-07-24 18:46:28 +00:00
Matthew Fredrickson
07f8e45a90 format.h: Fix a few minor errors in comments.
A few minor problems were found in comments in format.h.  This patch fixes them.

Change-Id: I07f0bdb47b93359b361c4c3d8ecc87cd3199dd94
2017-07-24 09:28:47 -05:00
Corey Farrell
df49ad2528 core: Add PARSE_TIMELEN support to ast_parse_arg and ACO.
This adds support for parsing timelen values from config files.  This
includes support for all flags which apply to PARSE_INT32.  Support for
this parser is added to ACO via the OPT_TIMELEN_T option type.

Fixes an issue where extra characters provided to ast_app_parse_timelen
were ignored, they now cause an error.

Testing is included.

ASTERISK-27117 #close

Change-Id: I6b333feca7e3f83b4ef5bf2636fc0fd613742554
2017-07-13 11:46:57 -04:00
George Joseph
eb48e99bd4 bridge_native_rtp: Keep rtp instance refs on bridge_channel
There have been reports of deadlocks caused by an attempt to send a frame
to a channel's rtp instance after the channel has left the native bridge
and been destroyed.  This patch effectively causes the bridge channel to
keep a reference to the glue and both the audio and video rtp instances
so what gets started will get stopped.

ASTERISK-26978 #close
Reported-by: Ross Beer

Change-Id: I9e1ac49fa4af68d64826ccccd152593cf8cdb21a
2017-06-27 11:08:19 -05:00
Torrey Searle
9fbc34d2bd res_pjsip: Add DTMF INFO Failback mode
The existing auto dtmf mode reverts to inband if 4733 fails to be
negotiated.  This patch adds a new mode auto_info which will
switch to INFO instead of inband if 4733 is not available.

ASTERISK-27066 #close

Change-Id: Id185b11e84afd9191a2f269e8443019047765e91
2017-06-23 09:15:24 +02:00
Kevin Harwell
1f9913f272 core_local: local channel data not being properly unref'ed and unlocked
In an earlier version of Asterisk a local channel [un]lock all functions were
added in order to keep a crash from occurring when a channel hung up too early
during an attended transfer. Unfortunately, when a transfer failure occurs and
depending on the timing, the local channels sometime do not get properly
unlocked and deref'ed after being locked and ref'ed. This happens because the
underlying local channel structure gets NULLed out before unlocking.

This patch reworks those [un]lock functions and makes sure the values that get
locked and ref'ed later get unlocked and deref'ed.

ASTERISK-27074 #close

Change-Id: Ice96653e29bd9d6674ed5f95feb6b448ab148b09
2017-06-21 16:17:02 -05:00
Jenkins2
707e0e62e6 Merge "res_pjsip: New endpoint option "notify_early_inuse_ringing"" into 13 2017-06-19 08:48:09 -05:00
Alexei Gradinari
a6e4899612 res_pjsip: New endpoint option "notify_early_inuse_ringing"
This option was added to control whether to notify dialog-info state
'early' or 'confirmed' on Ringing when already INUSE.
The value "yes" is useful for some SIP phones (Cisco SPA)
to be able to indicate and pick up ringing devices.

ASTERISK-26919 #close

Change-Id: Ie050bc30023543c7dfb4365c5be3ce58c738c711
2017-06-16 12:08:27 -04:00
Jenkins2
0b7a0681a3 Merge "res_ari: Add "module loaded" check to ari stubs" into 13 2017-06-16 10:57:43 -05:00
George Joseph
7901b9853e res_ari: Add "module loaded" check to ari stubs
The recent change to make the use of LOAD_DECLINE more consistent
caused res_ari to unload itself before declining if the ari.conf
file wasn't found.  The ari stubs though still tried to use the
configuration resulting in segfaults.

This patch creates a new CHECK_ARI_MODULE_LOADED macro which tests
to see if res_ari is actually loaded and causes the stubs to also
decline if it isn't.  The macro was then added to the mustache
template's "load_module" function.

ASTERISK-27026 #close
Reported-by: Ronald Raikes

Change-Id: I263d56efa628ee3c411bdcd16d49af6260c6c91d
2017-06-15 18:31:53 -06:00
Jenkins2
5fa52f0b5a Merge "bridge: Add a deferred queue." into 13 2017-06-15 14:48:39 -05:00
Joshua Colp
e414833f6e bridge: Add a deferred queue.
This change adds a deferred queue to bridging. If a bridge
technology determines that a frame can not be written and
should be deferred it can indicate back to bridging to do so.
Bridging will then requeue any deferred frames upon a new
channel joining the bridge.

This change has been leveraged for T.38 request negotiate
control frames. Without the deferred queue there is a race
condition between the bridge receiving the T.38 request
negotiate and the second channel joining and being in the
bridge. If the channel is not yet in the bridge then the T.38
negotiation fails.

A unit test has also been added that confirms that a T.38
request negotiate control frame is deferred when no other
channel is in the bridge and that it is requeued when a new
channel joins the bridge.

ASTERISK-26923

Change-Id: Ie05b08523f399eae579130f4a5f562a344d2e415
2017-06-13 22:05:28 +00:00
Kevin Harwell
6cdf3191d3 res_pjsip_refer/session: Calls dropped during transfer
When doing an attended transfer it's possible for the transferer, after
receiving an accepted response from Asterisk, to send a BYE to Asterisk,
which can then be processed before Asterisk has time to start and/or
complete the transfer process. This of course causes the transfer to not
complete successfully, thus dropping the call.

This patch makes it so any BYEs received from the transferer, after the REFER,
that initiate a session end are deferred until the transfer is complete. This
allows the channel that would have otherwise been hung up by Asterisk to
remain available throughout the transfer process.

ASTERISK-27053 #close

Change-Id: I43586db79079457d92d71f1fd993be9a3b409d5a
2017-06-13 14:17:29 -05:00
Jenkins2
812f5b51cb Merge "res_pjsip: Add support for returning only reachable contacts and use it." into 13 2017-06-07 08:11:23 -05:00
Joshua Colp
746c2c5745 res_pjsip: Add support for returning only reachable contacts and use it.
This introduces the ability for PJSIP code to specify filtering flags
when retrieving PJSIP contacts. The first flag for use causes the
query code to only retrieve contacts that are not unreachable. This
change has been leveraged by both the Dial() process and the
PJSIP_DIAL_CONTACTS dialplan function so they will now only attempt
calls to contacts which are not unreachable.

ASTERISK-26281

Change-Id: I8233b4faa21ba3db114f5a42e946e4b191446f6c
2017-06-06 14:45:49 +00:00
Jenkins2
95b2b542f6 Merge "format: Reintroduce smoother flags" into 13 2017-06-06 08:49:35 -05:00
Joshua Colp
3d7e9375fb Merge "res_srtp: Add support for libsrtp2" into 13 2017-06-06 05:00:57 -05:00
Jenkins2
3e8eea0325 Merge "res_pjsip: New endpoint option "refer_blind_progress"" into 13 2017-06-01 09:48:48 -05:00
Sean Bright
70e5887906 format: Reintroduce smoother flags
In review 4843 (ASTERISK-24858), we added a hack that forced a smoother
creation when sending signed linear so that the byte order was adjusted
during transmission. This was needed because smoother flags were lost
during the new format work that was done in Asterisk 13.

Rather than rolling that same hack into res_rtp_multicast, re-introduce
smoother flags so that formats can dictate their own options.

Change-Id: I77b835fba0e539c6ce50014a984766f63cab2c16
2017-05-30 15:08:05 -05:00
Sean Bright
5e9cd1f20d res_srtp: Add support for libsrtp2
ASTERISK-25294 #close
Reported by: Tzafrir Cohen

ASTERISK-26976 #close
Reported by: Alex

Change-Id: I789b1c3d1ed31365bbd9339fa58ef36f48833c40
2017-05-26 12:06:34 -04:00
Jenkins2
d4ccd3a6c0 Merge "asterisk: Audit locking of channel when manipulating flags." into 13 2017-05-26 09:12:11 -05:00
George Joseph
65898c3af8 unittests: Add a unit test that causes a SEGV and...
...that can only be run by explicitly calling it with
'test execute category /DO_NOT_RUN/ name RAISE_SEGV'

This allows us to more easily test CI and debugging tools that
should do certain things when asterisk coredumps.

To allow this a new member was added to the ast_test_info
structure named 'explicit_only'.  If set by a test, the test
will be skipped during a 'test execute all' or
'test execute category ...'.

Change-Id: Ia3a11856aae4887df9a02b6b081cc777b36eb6ed
2017-05-24 14:56:14 -06:00
Joshua Colp
1618203964 asterisk: Audit locking of channel when manipulating flags.
When manipulating flags on a channel the channel has to be
locked to guarantee that nothing else is also manipulating
the flags. This change introduces locking where necessary to
guarantee this. It also adds helper functions that manipulate
channel flags and lock to reduce repeated code.

ASTERISK-26789

Change-Id: I489280662dba0f4c50981bfc5b5a7073fef2db10
2017-05-16 14:25:01 +00:00
Alexei Gradinari
6af2dd34af res_pjsip: New endpoint option "refer_blind_progress"
This option was added to turn off notifying the progress details
on Blind Transfer. If this option is not set then the chan_pjsip
will send NOTIFY "200 OK" immediately after "202 Accepted".

Some SIP phones like Mitel/Aastra or Snom keep the line busy until
receive "200 OK".

ASTERISK-26333 #close

Change-Id: Id606fbff2e02e967c02138457badc399144720f2
2017-05-11 11:45:16 -04:00
George Joseph
7d4a22bf2e logger: Added logger_queue_limit to the configuration options.
All log messages go to a queue serviced by a single thread
which does all the IO.  This setting controls how big that
queue can get (and therefore how much memory is allocated)
before new messages are discarded. The default is 1000.
Should something go bezerk and log tons of messages in a tight
loop, this will prevent memory escalation.

When the limit is reached, a WARNING is logged to that effect
and messages are discarded until the queue is empty again.  At
that time another WARNING will be logged with the count of
discarded messages.  There's no "low water mark" for this queue
because the logger thread empties the entire queue and processes it
in 1 batch before going back and waiting on the queue again.
Implementing a low water mark would mean additional locking as
the thread processes each message and it's not worth it.

A "test" was added to test_logger.c but since the outcome is
non-deterministic, it's really just a cli command, not a unit
test.

Change-Id: Ib4520c95e1ca5325dbf584c7989ce391649836d1
2017-05-08 15:27:04 -06:00
Joshua Colp
7ffd80cc04 bridge: Fix returning to dialplan when executing Bridge() from AMI.
When using the Bridge AMI action on the same channel multiple times
it was possible for the channel to return to the wrong location in
the dialplan if the other party hung up. This happened because the
priority of the channel was not preserved across each action
invocation and it would fail to move on to the next priority in
other cases.

This change makes it so that the priority of a channel is preserved
when taking control of it from another thread and it is incremented
as appropriate such that the priority reflects where the channel
should next be executed in the dialplan, not where it may or may not
currently be.

The Bridge AMI action was also changed to ensure that it too
starts the channels at the next location in the dialplan.

ASTERISK-24529

Change-Id: I52406669cf64208aef7252a65b63ade31fbf7a5a
2017-05-04 21:39:22 +00:00
Jenkins2
9bb683242c Merge "res_pjsip_session: Add cleanup to ast_sip_session_terminate" into 13 2017-04-27 16:46:17 -05:00
George Joseph
c5b9ed20fd res_pjsip_session: Add cleanup to ast_sip_session_terminate
If you use ast_request to create a PJSIP channel but then hang it
up without causing a transaction to be sent, the session will
never be destroyed.  This is due ot the fact that it's pjproject
that triggers the session cleanup when the transaction ends.
app_chanisavail was doing this to get more granular channel state
and it's also possible for this to happen via ARI.

* ast_sip_session_terminate was modified to explicitly call the
  cleanup tasks and unreference session if the invite state is NULL
  AND invite_tsx is NULL (meaning we never sent a transaction).

* chan_pjsip/hangup was modified to bump session before it calls
  ast_sip_session_terminate to insure that session stays valid
  while it does its own cleanup.

* Added test events to session_destructor for a future testsuite
  test.

ASTERISK-26908 #close
Reported-by: Richard Mudgett

Change-Id: I52daf6f757184e5544c261f64f6fe9602c4680a9
2017-04-27 09:43:00 -06:00
Kevin Harwell
4d3b4fbf22 vector: defaults and indexes
Added an pre-defined integer vector declaration. This makes integer vectors
easier to declare and pass around. Also, added the ability to default a vector
up to a given size with a default value. Lastly, added functionality that
returns the "nth" index of a matching value.

Also, updated a unit test to test these changes.

Change-Id: Iaf4b51b2540eda57cb43f67aa59cf1d96cdbcaa5
2017-04-26 13:24:44 -05:00
Sean Bright
cea3742c54 core: Use eventfd for alert pipes on Linux when possible
The primary win of switching to eventfd when possible is that it only
uses a single file descriptor while pipe() will use two. This means for
each bridge channel we're reducing the number of required file
descriptors by 1, and - if you're using timerfd - we also now have 1
less file descriptor per Asterisk channel.

The API is not ideal (passing int arrays), but this is the cleanest
approach I could come up with to maintain API/ABI.

I've also removed what I believe to be an erroneous code block that
checked the non-blocking flag on the pipe ends for each read. If the
file descriptor is 'losing' its non-blocking mode, it is because of a
bug somewhere else in our code.

In my testing I haven't seen any measurable difference in performance.

Change-Id: Iff0fb1573e7f7a187d5211ddc60aa8f3da3edb1d
2017-04-24 12:46:27 -04:00
Joshua Colp
5e2a8ef94a Merge "modules: change module LOAD_FAILUREs to LOAD_DECLINES" into 13 2017-04-13 05:45:46 -05:00
George Joseph
f882ca2572 modules: change module LOAD_FAILUREs to LOAD_DECLINES
In all non-pbx modules, AST_MODULE_LOAD_FAILURE has been changed
to AST_MODULE_LOAD_DECLINE.  This prevents asterisk from exiting
if a module can't be loaded.  If the user wishes to retain the
FAILURE behavior for a specific module, they can use the "require"
or "preload-require" keyword in modules.conf.

A new API was added to logger: ast_is_logger_initialized().  This
allows asterisk.c/check_init() to print to the error log once the
logger subsystem is ready instead of just to stdout.  If something
does fail before the logger is initialized, we now print to stderr
instead of stdout.

Change-Id: I5f4b50623d9b5a6cb7c5624a8c5c1274c13b2b25
2017-04-12 16:46:22 -05:00
Torrey Searle
d8967ff2c0 strings.h: Avoid overflows in the string hash functions
On 2's compliment machines abs(INT_MIN) behavior is undefined and
results in a negative value still being returnd.  This results in
negative hash codes that can result in crashes.

ASTERISK-26528 #close

Change-Id: Idff550145ca2133792a61a2e212b4a3e82c6517b
2017-04-10 15:01:06 -05:00
George Joseph
4e6e069491 pjproject_bundled: Add 3 upstream patches
0035-r5572-svn-backport-dialog-transaction-deadlock.patch
0036-r5573-svn-backport-ua-pjsua-transaction-deadlock.patch
0037-r5576-svn-backport-session-timer-crash.patch

Also removed the progress bar from wget download to stdout.

ASTERISK-26905 #close
Reported-by: Ross Beer

Change-Id: I268fb3cf71a3bb24283ff0d24bd8b03239d81256
2017-04-05 16:16:42 -06:00
Corey Farrell
c701550803 Forward declare 'struct ast_json' in asterisk.h
The ast_json structure is used in many Asterisk headers and is often the
only part of json.h used.  This adds a forward declaration to asterisk.h
and removes the include of json.h from many headers.  The declaration
has been left in endpoints.h and stasis.h to avoid problems with source
files that use ast_json functions without directly including json.h.

ari.h continues to include json.h as it uses enum
ast_json_encoding_format.

Change-Id: Id766aabce6bed56626d27e8d29f559b5e687b769
2017-03-30 22:54:01 -05:00
zuul
f040eb0502 Merge "CEL: Remove header declarations of non-existant functions." into 13 2017-03-30 18:39:19 -05:00
Sean Bright
c9648f4690 astobj2: Prevent potential deadlocks with ao2_global_obj_release
The ao2_global_obj_release() function holds an exclusive lock on the
global object while it is being dereferenced. Any destructors that
run during this time that call ao2_global_obj_ref() will deadlock
because a read lock is required.

Instead, we make the global object inaccessible inside of the write
lock and only dereference it once we have released the lock. This
allows the affected destructors to fail gracefully.

While this doesn't completely solve the referenced issue (the error
message about not being able to create an IQ continues to be shown)
it does solve the backtrace spew that accompanied it.

ASTERISK-21009 #close
Reported by: Marcello Ceschia

Change-Id: Idf40ae136b5070dba22cb576ea8414fbc9939385
2017-03-30 13:49:49 -04:00
Corey Farrell
3c23ebdef4 CEL: Remove header declarations of non-existant functions.
ast_cel_alloc and ast_cel_destroy do not exist in code, remove them from
the headers.

Change-Id: I99ce848e2e109e7d61771559f559b9e57973e45c
2017-03-30 11:18:38 -04:00
Sean Bright
79a2c26c03 core: Remove embedded module support
This has not worked for some time and is no longer actively maintained.

Change-Id: I5110b0db69c152761b58fa025cb0a53b0e544d99
2017-03-27 10:36:23 -04:00
Kevin Harwell
f1b34e6eb4 AMI: Updated version
Updated the AMI version for the following reason (see CHANGES for more details):

The 'PJSIPShowEndpoint' command's response event of 'IdentifyDetail' now
contains a new optional parameter, 'MatchHeader'.

Change-Id: I9aeac4decc89f9b464b3f026e97c7ef1acc79242
2017-03-23 14:24:42 -05:00
zuul
b79e67ba47 Merge "res_pjsip_session: Enable RFC3578 overlap dialing support." into 13 2017-03-22 15:48:53 -05:00
Richard Begg
398e5ec16c res_pjsip_session: Enable RFC3578 overlap dialing support.
Support for RFC3578 overlap dialling (i.e. 484 Response to partially matched
destinations) as currently provided by chan_sip is missing from res_pjsip.
This patch adds a new endpoint attribute (allow_overlap) [defaults to yes]
which when set to yes enables 484 responses to partial destination
matches rather than the current 404.

ASTERISK-26864

Change-Id: Iea444da3ee7c7d4f1fde1d01d138a3d7b0fe40f6
2017-03-22 11:25:07 +00:00
zuul
d7ba743329 Merge "autochan/mixmonitor/chanspy: Fix unsafe channel locking and references." into 13 2017-03-21 19:47:25 -05:00
Sean Bright
218f618095 res_hep: Capture actual transport type in use
Rather than hard-coding UDP, allow consumers of the HEP API to specify
which protocol is in use. Update the PJSIP provider to pass in the
current protocol type.

ASTERISK-26850 #close

Change-Id: I54bbb0a001cfe4c6a87ad4b6f2014af233349978
2017-03-21 15:40:08 -04:00
Sean Bright
38cebc73a3 thread safety: Don't use getprotobyname()
POSIX does not require getprotobyname() to be thread safe and some
implementations use static memory which causes issues when multiple
threads are used.

Further, our usage of it today is just to ultimately get IPPROTO_TCP
for calls to setsockopt(). So instead we just use IPPROTO_TCP directly.

Change-Id: I2e14e58674808f7ce99b2f5e900d0f90d0d8da48
2017-03-20 08:51:47 -04:00
George Joseph
9b756662a8 res_pjsip: Symmetric transports
A new transport parameter 'symmetric_transport' has been added.

When a request from a dynamic contact comes in on a transport with
this option set to 'yes', the transport name will be saved and used
for subsequent outgoing requests like OPTIONS, NOTIFY and INVITE.
It's saved as a contact uri parameter named 'x-ast-txp' and will
display with the contact uri in CLI, AMI, and ARI output.  On the
outgoing request, if a transport wasn't explicitly set on the
endpoint AND the request URI is not a hostname, the saved transport
will be used and the 'x-ast-txp' parameter stripped from the
outgoing packet.

* config_transport was modified to accept and store the new parameter.

* config_transport/transport_apply was updated to store the transport
  name in the pjsip_transport->info field using the pjsip_transport->pool
  on UDP transports.

* A 'multihomed_on_rx_message' function was added to
  pjsip_message_ip_updater that, for incoming requests, retrieves the
  transport name from pjsip_transport->info and retrieves the transport.
  If transport->symmetric_transport is set, an 'x-ast-txp' uri parameter
  containing the transport name is added to the incoming Contact header.

* An 'ast_sip_get_transport_name' function was added to res_pjsip.
  It takes an ast_sip_endpoint and a pjsip_sip_uri and returns a
  transport name if endpoint->transport is set or if there's an
  'x-ast-txp' parameter on the uri and the uri host is an ipv4 or
  ipv6 address.  Otherwise it returns NULL.

* An 'ast_sip_dlg_set_transport' function was added to res_pjsip
  which takes an ast_sip_endpoint, a pjsip_dialog, and an optional
  pjsip_tpselector.  It calls ast_sip_get_transport_name() and if
  a non-NULL is returned, sets the selector and sets the transport
  on the dialog.  If a selector was passed in, it's updated.

* res_pjsip/ast_sip_create_dialog_uac and ast_sip_create_dialog_uas
  were modified to call ast_sip_dlg_set_transport() instead of their
  original logic.

* res_pjsip/create_out_of_dialog_request was modified to call
  ast_sip_get_transport_name() and pjsip_tx_data_set_transport()
  instead of its original logic.

* Existing transport logic was removed from endpt_send_request
  since that can only be called after a create_out_of_dialog_request.

* res_pjsip/ast_sip_create_rdata was converted to a wrapper around
  a new 'ast_sip_create_rdata_with_contact' function which allows
  a contact_uri to be specified in addition to the existing
  parameters.  (See below)

* res_pjsip_pubsub/internal_pjsip_evsub_send_request was eliminated
  since all it did was transport selection and that is now done in
  ast_sip_create_dialog_uac and ast_sip_create_dialog_uas.

* 'contact_uri' was added to subscription_persistence.  This was
  necessary because although the parsed rdata contact header has the
  x-ast-txp parameter added (if appropriate),
  subscription_persistence_update stores the raw packet which
  doesn't have it.  subscription_persistence_recreate was then
  updated to call ast_sip_create_rdata_with_contact with the
  persisted contact_uri so the recreated subscription has the
  correct transport info to send the NOTIFYs.

* res_pjsip_session/internal_pjsip_inv_send_msg was eliminated since
  all it did was transport selection and that is now done in
  ast_sip_create_dialog_uac.

* pjsip_message_ip_updater/multihomed_on_tx_message was updated
  to remove all traces of the x-ast-txp parameter from the
  outgoing headers.

NOTE:  This change does NOT modify the behavior of permanent
contacts specified on an aor.  To do so would require that the
permanent contact's contact uri be updated with the x-ast-txp
parameter and the aor sorcery object updated.  If we need to
persue this, we need to think about cloning permanent contacts into
the same store as the dynamic ones on an aor load so they can be
updated without disturbing the originally configured value.

You CAN add the x-ast-txp parameter to a permanent contact's uri
but it would be much simpler to just set endpoint->transport.

Change-Id: I4ee1f51473da32ca54b877cd158523efcef9655f
2017-03-16 08:03:26 -06:00
Richard Mudgett
adad6020be autochan/mixmonitor/chanspy: Fix unsafe channel locking and references.
Dereferencing struct ast_autochan.chan without first calling
ast_autochan_channel_lock() is unsafe because the pointer could change at
any time due to a masquerade.  Unfortunately, ast_autochan_channel_lock()
itself uses struct ast_autochan.chan unsafely and can result in a deadlock
if the original channel happens to get destroyed after a masquerade in
addition to the pointer getting changed.

The problem is more likely to happen with v11 and earlier because
masquerades are used to optimize out local channels on those versions.
However, it could still happen on newer versions if the channel is
executing a dialplan application when the channel is transferred or
redirected.  In this situation a masquerade still must be used.

* Added a lock to struct ast_autochan to safely be able to use
ast_autochan.chan while trying to get the channel lock in
ast_autochan_channel_lock().  The locking order is the channel lock then
the autochan lock.  Locking in the other direction requires deadlock
avoidance.

* Fix unsafe ast_autochan.chan usages in app_mixmonitor.c.

* Fix unsafe ast_autochan.chan usages in app_chanspy.c.

* app_chanspy.c: Removed unused autochan parameter from next_channel().

ASTERISK-26867

Change-Id: Id29dd22bc0f369b44e23ca423d2f3657187cc592
2017-03-15 17:43:54 -05:00