X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;f=libs%2Fsrtp%2Fsrtp.c;h=c9414374a42b63db0a3b605a74fbc02657372355;hb=5c09dbbad9c76ea76d7060b0fee10b7d3c8abb3a;hp=f60147bfa6c0dcdabda9b5ea160787ff83168c82;hpb=54a4638723464f86744b43be273474367a131891;p=vlc

diff --git a/libs/srtp/srtp.c b/libs/srtp/srtp.c
index f60147bfa6..c9414374a4 100644
--- a/libs/srtp/srtp.c
+++ b/libs/srtp/srtp.c
@@ -651,6 +651,7 @@ srtcp_send (srtp_session_t *s, uint8_t *buf, size_t *lenp, size_t bufsize)
     const uint8_t *tag = rtcp_digest (s->rtp.mac, buf, len);
     memcpy (buf + len, tag, s->tag_len);
     *lenp = len + s->tag_len;
+    s->rtcp_index++; /* Update index */
     return 0;
 }
 
@@ -682,8 +683,13 @@ srtcp_recv (srtp_session_t *s, uint8_t *buf, size_t *lenp)
          return EACCES;
 
     len -= 4; /* Remove SRTCP index before decryption */
-    *lenp = len;
+    uint32_t index;
+    memcpy (&index, buf + len, 4);
+    index = ntohl (index);
+    if (((index - s->rtcp_index) & 0xffffffff) < 0x80000000)
+        s->rtcp_index = index; /* Update index */
 
+    *lenp = len;
     return srtp_crypt (s, buf, len);
 }