Changeset 54a4638723464f86744b43be273474367a131891

Timestamp:

03/10/07 21:00:10 (1 year ago)

Author:

Rémi Denis-Courmont <rem@videolan.org>

git-committer:

Rémi Denis-Courmont <rem@videolan.org> 1173556810 +0000

git-parent:

[a7c26dab2123bdc2fbb285d7aaeed6d66976b4d4]

git-author:

Rémi Denis-Courmont <rem@videolan.org> 1173556810 +0000

Message:

Fix SRTP Roll-Over-Counter handling

Files:

• libs/srtp/srtp.c (modified) (4 diffs)

libs/srtp/srtp.c

@@ -388 +388 @@
-
-
+/** Determines SRTP Roll-Over-Counter (in host-byte order) */
+static uint32_t
+srtp_compute_roc (const srtp_session_t *s, uint16_t seq)
+{
+    uint32_t roc = s->rtp_roc;
+
+    if (((seq - s->rtp_seq) & 0xffff) < 0x8000)
+    {
+        /* Sequence is ahead, good */
+        if (seq < s->rtp_seq)
+            roc++; /* Sequence number wrap */
+    }
+    else
+    {
+        /* Sequence is late, bad */
+        if (seq > s->rtp_seq)
+            roc--; /* Wrap back */
+    }
+    return roc;
+}
+
+
+/** Returns RTP sequence (in host-byte order) */
+static inline uint16_t rtp_seq (const uint8_t *buf)
+{
+    return (buf[2] << 8) | buf[3];
+}
+
+
-/** Message Authentication and Integrity for RTP */
-static const uint8_t *
-
-
+
+
+
+
+
-    gcry_md_reset (md);
-    gcry_md_write (md, data, len);
-(uint32_t){ htonl (roc) }
+roc
-    return gcry_md_read (md, 0);
-}
@@ -437 +469 @@
-
-    /* Determines RTP 48-bits counter and SSRC */
-
+
+
-    memcpy (&ssrc, buf + 8, 4);
-
-
-
-
-
-
-
+
+
+
-    else
-
-
-
-
-
-
-
+
+
+
+
-    if (s->flags & SRTP_UNENCRYPTED)
-        return 0;
-
-s->rtp_
+
-                   buf + offset, len - offset))
-        return EINVAL;
@@ -487 +514 @@
-        return val;
-
-s->flags & SRTP_UNAUTHENTICATED
-    return 0;
-
-if (bufsize < (len + s->tag_len))
-
-
-const uint8_t *tag = rtp_digest (s->rtp.mac, buf, len, s->rtp_roc
-memcpy (buf + len, tag, s->tag_len)
-*lenp = len + s->tag_len;
+!(s->flags & SRTP_UNAUTHENTICATED)
+{
+
+        return ENOSPC;
+
+
+    memcpy (buf + len, tag, s->tag_len
+    *lenp = len + s->tag_len
+}
-
-    return 0;
@@ -521 +548 @@
-    if (!(s->flags & SRTP_UNAUTHENTICATED))
-    {
-s->tag_len
+(12u + s->tag_len)
-            return EINVAL;
-        len -= s->tag_len;
-
-->rtp.mac, buf, len, s->rtp_roc
+, buf, len
-        if (memcmp (buf + len, tag, s->tag_len))
-            return EACCES;