Certificate Transparency TLS extension patch for NSS

net/third_party/nss/ssl/ssl3con.c

Index: net/third_party/nss/ssl/ssl3con.c
diff --git a/net/third_party/nss/ssl/ssl3con.c b/net/third_party/nss/ssl/ssl3con.c
index 7b93a63c5ebf3e692dd2fe70a6b841b525da49c1..ceb31bc101420af931b86a216a9ab5525e8a7257 100644
--- a/net/third_party/nss/ssl/ssl3con.c
+++ b/net/third_party/nss/ssl/ssl3con.c
@@ -6612,6 +6612,18 @@ ssl3_HandleServerHello(sslSocket *ss, SSL3Opaque *b, PRUint32 length)
     sid->u.ssl3.sessionIDLength = sidBytes.len;
     PORT_Memcpy(sid->u.ssl3.sessionID, sidBytes.data, sidBytes.len);
 
+    /* Copy Signed Certificate Timestamps, if any. */

[wtc, 2013/11/08 19:51:31]

So if session resumption succeeds, we ignore any Signed Certificate Timestamps
that we have received, correct?

Update: RFC 6962 Sec. 3.3.1 answers my question:

   Session resumption uses the original session information: clients
   SHOULD include the extension type in the ClientHello, but if the
   session is resumed, the server is not expected to process it or
   include the extension in the ServerHello.

I guess this implies if the server still includes the extension in the
ServerHello, the extension is ignored by the client.

[ekasper, 2013/11/18 17:47:18]

Correct.

+    if (ss->xtnData.signedCertTimestamps.data) {
+	rv = SECITEM_CopyItem(NULL, &sid->u.ssl3.signedCertTimestamps,
+			      &ss->xtnData.signedCertTimestamps);
+	if (rv != SECSuccess)
+	    goto loser;
+    }
+
+    /* Clean up the temporary pointer to the handshake buffer. */
+    ss->xtnData.signedCertTimestamps.data = NULL;
+    ss->xtnData.signedCertTimestamps.len = 0;

[wtc, 2013/11/08 19:51:31]

Nit: these three lines can be moved into the preceding if statement.

[ekasper, 2013/11/18 17:47:18]

Actually, uh, they belong to the winner: block below, otherwise the goto winner;
above misses this.

+
     ss->ssl3.hs.isResuming = PR_FALSE;
     ss->ssl3.hs.ws         = wait_server_cert;
 
@@ -6641,6 +6653,9 @@ alert_loser:
     (void)SSL3_SendAlert(ss, alert_fatal, desc);
 
 loser:
+    /* Clean up the temporary pointer to the handshake buffer. */
+    ss->xtnData.signedCertTimestamps.data = NULL;
+    ss->xtnData.signedCertTimestamps.len = 0;
     errCode = ssl_MapLowLevelError(errCode);
     return SECFailure;
 }