net: don't add padding extension for SSLv3.

net/third_party/nss/patches/paddingextension.patch

 diff --git a/nss/lib/ssl/ssl3con.c b/nss/lib/ssl/ssl3con.c
-index 8b8b758..567d481 100644
+index 8b8b758..25709b2 100644
 --- a/nss/lib/ssl/ssl3con.c
 +++ b/nss/lib/ssl/ssl3con.c
 @@ -4975,6 +4975,7 @@ ssl3_SendClientHello(sslSocket *ss, PRBool resending)
      PRBool           isTLS = PR_FALSE;
      PRBool           requestingResume = PR_FALSE;
      PRInt32          total_exten_len = 0;
 +    unsigned         paddingExtensionLen;
      unsigned         numCompressionMethods;
      PRInt32          flags;
  
-@@ -5241,6 +5242,20 @@ ssl3_SendClientHello(sslSocket *ss, PRBool resending)
+@@ -5241,6 +5242,22 @@ ssl3_SendClientHello(sslSocket *ss, PRBool resending)
         length += 1 + ss->ssl3.hs.cookieLen;
      }
  
 +    /* A padding extension may be included to ensure that the record containing
 +     * the ClientHello doesn't have a length between 256 and 511 bytes
 +     * (inclusive). Initial, ClientHello records with such lengths trigger bugs
 +     * in F5 devices.
 +     *
 +     * This is not done for DTLS nor for renegotiation. */
-+    if (!IS_DTLS(ss) && !ss->firstHsDone) {
++    if (!IS_DTLS(ss) &&
++        ss->version > SSL_LIBRARY_VERSION_3_0 &&
++        !ss->firstHsDone) {
 +        paddingExtensionLen = ssl3_CalculatePaddingExtensionLength(length);
 +        total_exten_len += paddingExtensionLen;
 +        length += paddingExtensionLen;
 +    } else {
 +        paddingExtensionLen = 0;
 +    }
 +
      rv = ssl3_AppendHandshakeHeader(ss, client_hello, length);
      if (rv != SECSuccess) {
         return rv;      /* err set by ssl3_AppendHandshake* */
-@@ -5360,6 +5375,13 @@ ssl3_SendClientHello(sslSocket *ss, PRBool resending)
+@@ -5360,6 +5377,13 @@ ssl3_SendClientHello(sslSocket *ss, PRBool resending)
             return SECFailure;
         }
         maxBytes -= extLen;
 +
 +       extLen = ssl3_AppendPaddingExtension(ss, paddingExtensionLen, maxBytes);
 +       if (extLen < 0) {
 +           return SECFailure;
 +       }
 +       maxBytes -= extLen;
 +
@@ skipping 88 matching lines @@
      ssl_next_proto_nego_xtn          = 13172,
      ssl_channel_id_xtn               = 30031,
 +    ssl_padding_xtn                  = 35655,
      ssl_renegotiation_info_xtn       = 0xff01  /* experimental number */
  } SSLExtensionType;
  
 -#define SSL_MAX_EXTENSIONS             11
 +#define SSL_MAX_EXTENSIONS             11 /* doesn't include ssl_padding_xtn. */
  
  #endif /* __sslt_h_ */