Don't resend payload after Snap Start misprediction.

net/socket/ssl_client_socket_nss.cc

Index: net/socket/ssl_client_socket_nss.cc
diff --git a/net/socket/ssl_client_socket_nss.cc b/net/socket/ssl_client_socket_nss.cc
index 5e607782631a2b034445aff47800647420618b14..d13b2a9b9f5773b912b7dc8102da045428ae016b 100644
--- a/net/socket/ssl_client_socket_nss.cc
+++ b/net/socket/ssl_client_socket_nss.cc
@@ -2265,11 +2265,29 @@ int SSLClientSocketNSS::DoVerifyCertComplete(int result) {
   // session with a bad cert.
   InvalidateSessionIfBadCertificate();
 
-  // Likewise, if we merged a Write call into the handshake we need to make the
+  // If we merged a Write call into the handshake we need to make the
   // callback now.
   if (user_write_callback_) {
     corked_ = false;
-    DoWriteCallback(user_write_buf_len_);
+    if (result != OK) {
+      DoWriteCallback(result);
+    } else {
+      SSLSnapStartResult snap_start_type;
+      SECStatus rv = SSL_GetSnapStartResult(nss_fd_, &snap_start_type);
+      DCHECK_EQ(rv, SECSuccess);
+      DCHECK_NE(snap_start_type, SSL_SNAP_START_NONE);
+      if (snap_start_type == SSL_SNAP_START_RECOVERY ||
+          snap_start_type == SSL_SNAP_START_RESUME_RECOVERY) {
+        // If we mispredicted the server's handshake then Snap Start will have
+        // triggered a recovery mode. The misprediction could have been caused
+        // by the server having a different certificate so the application data
+        // wasn't resent. Now that we have verified the certificate, we need to
+        // resend the application data.
+        int bytes_written = DoPayloadWrite();
+        if (bytes_written != ERR_IO_PENDING)
+          DoWriteCallback(bytes_written);
+      }

[wtc, 2010/11/02 22:29:17]

IMPORTANT: I believe we need to add 'else' here, at line 2289, for the
snap-start correct prediction case:
      } else {
        DoWriteCallback(user_write_buf_len_);
      }

Do you agree?

Basically, inside the if (user_write_callback_) statement that starts on line
2270, we should always call DoWriteCallback except when the
DoPayloadWrite call on line 2286 returns ERR_IO_PENDING.

+    }
   }
 
   // Exit DoHandshakeLoop and return the result to the caller to Connect.