res_rtp_asterisk: Make P2P bridge Asymmetric codec aware
authorTorrey Searle <torrey@voxbone.com>
Fri, 28 Jul 2017 12:53:44 +0000 (14:53 +0200)
committerTorrey Searle <tsearle@gmail.com>
Wed, 9 Aug 2017 13:57:50 +0000 (08:57 -0500)
Introduce a new property to rtp-engine to make it aware of
the desire for assymetric codecs or not.  If asymmetric codecs
is not allowed, the bridge will compare read/write formats
and shut down the p2p bridge if needed

ASTERISK-26745 #close

Change-Id: I0d9c83e5356df81661e58d40a8db565833501a6f

channels/chan_pjsip.c
include/asterisk/rtp_engine.h
res/res_pjsip_sdp_rtp.c
res/res_rtp_asterisk.c

index ebda6c7..4a24fa6 100644 (file)
@@ -797,14 +797,13 @@ static struct ast_frame *chan_pjsip_read_stream(struct ast_channel *ast)
                return f;
        }
 
-       if (ast_format_cap_iscompatible_format(ast_channel_nativeformats(ast), f->subclass.format) == AST_FORMAT_CMP_NOT_EQUAL) {
-               ast_debug(1, "Oooh, got a frame with format of %s on channel '%s' when it has not been negotiated\n",
-                       ast_format_get_name(f->subclass.format), ast_channel_name(ast));
-
-               ast_frfree(f);
-               return &ast_null_frame;
-       }
+       session = channel->session;
 
+       /*
+        * Asymmetric RTP only has one native format set at a time.
+        * Therefore we need to update the native format to the current
+        * raw read format BEFORE the native format check
+        */
        if (!session->endpoint->asymmetric_rtp_codec &&
                ast_format_cmp(ast_channel_rawwriteformat(ast), f->subclass.format) == AST_FORMAT_CMP_NOT_EQUAL) {
                struct ast_format_cap *caps;
@@ -831,6 +830,14 @@ static struct ast_frame *chan_pjsip_read_stream(struct ast_channel *ast)
                }
        }
 
+       if (ast_format_cap_iscompatible_format(ast_channel_nativeformats(ast), f->subclass.format) == AST_FORMAT_CMP_NOT_EQUAL) {
+               ast_debug(1, "Oooh, got a frame with format of %s on channel '%s' when it has not been negotiated\n",
+                       ast_format_get_name(f->subclass.format), ast_channel_name(ast));
+
+               ast_frfree(f);
+               return &ast_null_frame;
+       }
+
        if (session->dsp) {
                int dsp_features;
 
index d030bdb..3ceac84 100644 (file)
@@ -120,6 +120,8 @@ enum ast_rtp_property {
        AST_RTP_PROPERTY_STUN,
        /*! Enable RTCP support */
        AST_RTP_PROPERTY_RTCP,
+       /*! Enable Asymmetric RTP Codecs */
+       AST_RTP_PROPERTY_ASYMMETRIC_CODEC,
 
        /*!
         * \brief Maximum number of RTP properties supported
index 77cd807..b082b1d 100644 (file)
@@ -202,6 +202,7 @@ static int create_rtp(struct ast_sip_session *session, struct ast_sip_session_me
        }
 
        ast_rtp_instance_set_prop(session_media->rtp, AST_RTP_PROPERTY_NAT, session->endpoint->media.rtp.symmetric);
+       ast_rtp_instance_set_prop(session_media->rtp, AST_RTP_PROPERTY_ASYMMETRIC_CODEC, session->endpoint->asymmetric_rtp_codec);
 
        if (!session->endpoint->media.rtp.ice_support && (ice = ast_rtp_instance_get_ice(session_media->rtp))) {
                ice->stop(session_media->rtp);
index 65ab902..0ff2b55 100644 (file)
@@ -313,6 +313,7 @@ struct ast_rtp {
        void *data;
        struct ast_rtcp *rtcp;
        struct ast_rtp *bridged;        /*!< Who we are Packet bridged to */
+       unsigned int asymmetric_codec;  /*!< Indicate if asymmetric send/receive codecs are allowed */
 
        struct ast_rtp_instance *bundled; /*!< The RTP instance we are bundled to */
        int stream_num; /*!< Stream num for this RTP instance */
@@ -5113,6 +5114,23 @@ static int bridge_p2p_rtp_write(struct ast_rtp_instance *instance,
                return -1;
        }
 
+
+       ao2_replace(rtp->lastrxformat, payload_type->format);
+       ao2_replace(bridged->lasttxformat, payload_type->format);
+
+       /*
+        * If bridged peer has already received rtp, perform the asymmetric codec check
+        * if that feature has been activated
+        */
+       if (!bridged->asymmetric_codec && bridged->lastrxformat != ast_format_none) {
+               if (ast_format_cmp(bridged->lasttxformat, bridged->lastrxformat) == AST_FORMAT_CMP_NOT_EQUAL) {
+                       ast_debug(1, "Asymmetric RTP codecs detected (TX: %s, RX: %s) sending frame to core\n",
+                                       ast_format_get_name(bridged->lasttxformat),
+                                       ast_format_get_name(bridged->lastrxformat));
+                       return -1;
+               }
+       }
+
        /* If the marker bit has been explicitly set turn it on */
        if (ast_test_flag(rtp, FLAG_NEED_MARKER_BIT)) {
                mark = 1;
@@ -5797,6 +5815,8 @@ static void ast_rtp_prop_set(struct ast_rtp_instance *instance, enum ast_rtp_pro
                                rtp->rtcp = NULL;
                        }
                }
+       } else if (property == AST_RTP_PROPERTY_ASYMMETRIC_CODEC) {
+               rtp->asymmetric_codec = value;
        }
 }