Changeset 5588 for pjproject/trunk/pjmedia/src/pjmedia/transport_srtp.c

Timestamp:

Apr 25, 2017 2:13:56 PM (7 years ago)

Author:

riza

Message:

Re #1994 (misc): Related to r5500, when receiving an SDP answer for SRTP, process the tag correctly based on the offer. Thanks to Colin Morelli for the report.

File:

• pjproject/trunk/pjmedia/src/pjmedia/transport_srtp.c (modified) (8 diffs)

pjproject/trunk/pjmedia/src/pjmedia/transport_srtp.c

@@ -1618 +1618 @@
 
 
+static pj_status_t fill_local_crypto(pj_pool_t *pool,
+                                     const pjmedia_sdp_media *m_loc, 
+                                     pjmedia_srtp_crypto loc_crypto[],
+                                     int *count)
+{
+    int i;
+    int crypto_count = 0;
+    pj_status_t status = PJ_SUCCESS;
+    
+    for (i = 0; i < *count; ++i) {
+        pj_bzero(&loc_crypto[i], sizeof(loc_crypto[i]));
+    }
+
+    for (i = 0; i < (int)m_loc->attr_count; ++i) {      
+        pjmedia_srtp_crypto tmp_crypto;
+        int loc_tag;
+
+        if (pj_stricmp(&m_loc->attr[i]->name, &ID_CRYPTO) != 0)
+            continue;
+
+        status = parse_attr_crypto(pool, m_loc->attr[i],
+                                   &tmp_crypto, &loc_tag);
+        if (status != PJ_SUCCESS)
+            return status;
+
+        if (loc_tag > *count)
+            return PJMEDIA_SRTP_ESDPINCRYPTOTAG;
+
+        loc_crypto[loc_tag-1] = tmp_crypto;
+        ++crypto_count;
+    }
+    *count = crypto_count;
+    return status;
+}
+
 
 static pj_status_t transport_media_start(pjmedia_transport *tp,
@@ -1629 +1664 @@
     pj_status_t status;
     unsigned i;
+    pjmedia_srtp_crypto loc_crypto[PJMEDIA_SRTP_MAX_CRYPTOS];
+    int loc_cryto_cnt = PJMEDIA_SRTP_MAX_CRYPTOS;
 
     PJ_ASSERT_RETURN(tp && pool && sdp_local && sdp_remote, PJ_EINVAL);
@@ -1661 +1698 @@
                 //return PJMEDIA_SDP_EINPROTO;
             //}
+            fill_local_crypto(srtp->pool, m_loc, loc_crypto, &loc_cryto_cnt);
         } else if (srtp->setting.use == PJMEDIA_SRTP_MANDATORY) {
             if (pj_stricmp(&m_rem->desc.transport, &ID_RTP_SAVP)) {
@@ -1666 +1704 @@
                 return PJMEDIA_SDP_EINPROTO;
             }
+            fill_local_crypto(srtp->pool, m_loc, loc_crypto, &loc_cryto_cnt);
         }
     }
@@ -1674 +1713 @@
         pj_bool_t has_crypto_attr = PJ_FALSE;
         int rem_tag;
+        int j;
 
         for (i=0; i<m_rem->attr_count; ++i) {
@@ -1693 +1733 @@
 
 
-            /* our offer tag is always ordered by setting */
-            if (rem_tag < 1 || rem_tag > (int)srtp->setting.crypto_count) {
+            /* Tag range check, our tags in the offer must be in the SRTP 
+             * setting range, so does the remote answer's. The remote answer's 
+             * tag must not exceed the tag range of the local offer.
+             */
+            if (rem_tag < 1 || rem_tag > (int)srtp->setting.crypto_count ||
+                rem_tag > loc_cryto_cnt) 
+            
+            {
                 DEACTIVATE_MEDIA(pool, m_loc);
                 return PJMEDIA_SRTP_ESDPINCRYPTOTAG;
@@ -1700 +1746 @@
 
             /* match the crypto name */
-            if (pj_stricmp(&tmp_tx_crypto.name,
-                &srtp->setting.crypto[rem_tag-1].name) != 0)
+            if (pj_stricmp(&tmp_tx_crypto.name, 
+                           &loc_crypto[rem_tag-1].name) != 0)           
             {
                 DEACTIVATE_MEDIA(pool, m_loc);
@@ -1707 +1753 @@
             }
 
-            srtp->tx_policy_neg = srtp->setting.crypto[rem_tag-1];
+            /* Find the crypto from the setting. */
+            for (j = 0; j < (int)srtp->setting.crypto_count; ++j) {
+                if (pj_stricmp(&tmp_tx_crypto.name, 
+                               &srtp->setting.crypto[j].name) == 0) 
+                
+                {
+                    srtp->tx_policy_neg = srtp->setting.crypto[j];
+                    break;
+                }               
+            }
+            
             srtp->rx_policy_neg = tmp_tx_crypto;
         }