QUIC - Record reject reasons for CHLO message.

net/quic/crypto/quic_crypto_client_config.cc

Index: net/quic/crypto/quic_crypto_client_config.cc
diff --git a/net/quic/crypto/quic_crypto_client_config.cc b/net/quic/crypto/quic_crypto_client_config.cc
index b37befea03e661e50600e9ec3b5b2136cac00d8d..265fd949b6a9c71a3d397491bc2f051e1663fba1 100644
--- a/net/quic/crypto/quic_crypto_client_config.cc
+++ b/net/quic/crypto/quic_crypto_client_config.cc
@@ -4,6 +4,7 @@
 
 #include "net/quic/crypto/quic_crypto_client_config.h"
 
+#include "base/metrics/sparse_histogram.h"
 #include "base/stl_util.h"
 #include "base/strings/string_util.h"
 #include "net/quic/crypto/cert_compressor.h"
@@ -592,16 +593,57 @@ QuicErrorCode QuicCryptoClientConfig::ProcessRejection(
   COMPILE_ASSERT(sizeof(QuicTag) == sizeof(uint32), header_out_of_sync);
   if (rej.GetTaglist(kRREJ, &reject_reasons,
                      &num_reject_reasons) == QUIC_NO_ERROR) {
-#if defined(DEBUG)
+    uint32 packed_error = 0;
     for (size_t i = 0; i < num_reject_reasons; ++i) {
-      DVLOG(1) << "Reasons for rejection: " << reject_reasons[i];
+      HandshakeFailureReason reason =
+          static_cast<HandshakeFailureReason>(reject_reasons[i]);
+      packed_error |= RejectReasonToPackedError(reason);
     }
-#endif
+    UMA_HISTOGRAM_SPARSE_SLOWLY("Net.QuicClientHelloRejectReasons",
+                                packed_error);
   }
 
   return QUIC_NO_ERROR;
 }
 
+uint32 QuicCryptoClientConfig::RejectReasonToPackedError(
+    HandshakeFailureReason reason) {
+  // The return value is uploaded to UMA, they cannot be changed.
+  switch (reason) {
+    case HANDSHAKE_OK:
+      return 0;
+    case CLIENT_NONCE_UNKNOWN_FAILURE:

[Ryan Hamilton, 2014/06/24 21:09:24]

Let's renumber these enum values to avoid the gaps and then simply do:

return 1 << reason;

[ramant (doing other things), 2014/07/14 22:04:13]

Done.

+      return 1u << 5;
+    case CLIENT_NONCE_INVALID_FAILURE:
+      return 2u << 5;
+    case SERVER_NONCE_INVALID_FAILURE:
+      return 1u << 10;
+    case SERVER_NONCE_DECRYPTION_FAILURE:
+      return 2u << 10;
+    case SERVER_NONCE_NOT_UNIQUE_FAILURE:
+      return 3u << 10;
+    case SERVER_CONFIG_INCHOATE_HELLO_FAILURE:
+      return 1u << 15;
+    case SERVER_CONFIG_UNKNOWN_CONFIG_FAILURE:
+      return 2u << 15;
+    case SOURCE_ADDRESS_TOKEN_INVALID_FAILURE:
+      return 1u << 20;
+    case SOURCE_ADDRESS_TOKEN_DECRYPTION_FAILURE:
+      return 2u << 20;
+    case SOURCE_ADDRESS_TOKEN_PARSE_FAILURE:
+      return 3u << 20;
+    case SOURCE_ADDRESS_TOKEN_DIFFERENT_IP_ADDRESS_FAILURE:
+      return 4u << 20;
+    case SOURCE_ADDRESS_TOKEN_CLOCK_SKEW_FAILURE:
+      return 5u << 20;
+    case SOURCE_ADDRESS_TOKEN_EXPIRED_FAILURE:
+      return 6u << 20;
+    default:
+      NOTREACHED();
+      return 1u << 31;
+  }
+}
+
 QuicErrorCode QuicCryptoClientConfig::ProcessServerHello(
     const CryptoHandshakeMessage& server_hello,
     QuicConnectionId connection_id,