Disable QUIC trial decryption in V44 and above

gfe-relnote: Protected by reloadable flag quic_v44_disable_trial_decryption
PiperOrigin-RevId: 246159430
Change-Id: I7a1845d0a38555ce774dd58372f4ba19b12e777c

quic/core/quic_framer.cc

diff --git a/quic/core/quic_framer.cc b/quic/core/quic_framer.cc
index 20dc57c..67d32e3 100644
--- a/quic/core/quic_framer.cc
+++ b/quic/core/quic_framer.cc
@@ -3975,6 +3975,7 @@
   QuicDecrypter* decrypter = decrypter_[level].get();
   QuicDecrypter* alternative_decrypter = nullptr;
   if (version().KnowsWhichDecrypterToUse()) {
+    QUIC_RELOADABLE_FLAG_COUNT(quic_v44_disable_trial_decryption);
     level = GetEncryptionLevel(header);
     decrypter = decrypter_[level].get();
     if (decrypter == nullptr) {

quic/core/quic_framer_test.cc

diff --git a/quic/core/quic_framer_test.cc b/quic/core/quic_framer_test.cc
index dd4a701..0437118 100644
--- a/quic/core/quic_framer_test.cc
+++ b/quic/core/quic_framer_test.cc
@@ -3252,6 +3252,7 @@
     // not arise.
     return;
   }
+  SetDecrypterLevel(ENCRYPTION_FORWARD_SECURE);
 
   // clang-format off
   PacketFragments packet = {
@@ -3833,6 +3834,7 @@
 }
 
 TEST_P(QuicFramerTest, AckFrameTimeStampDeltaTooHigh) {
+  SetDecrypterLevel(ENCRYPTION_FORWARD_SECURE);
   // clang-format off
   unsigned char packet[] = {
       // public flags (8 byte connection_id)
@@ -3924,6 +3926,7 @@
 }
 
 TEST_P(QuicFramerTest, AckFrameTimeStampSecondDeltaTooHigh) {
+  SetDecrypterLevel(ENCRYPTION_FORWARD_SECURE);
   // clang-format off
   unsigned char packet[] = {
       // public flags (8 byte connection_id)
@@ -4030,6 +4033,7 @@
   if (version_.transport_version == QUIC_VERSION_99) {
     return;
   }
+  SetDecrypterLevel(ENCRYPTION_FORWARD_SECURE);
   // clang-format off
   PacketFragments packet = {
       // public flags (8 byte connection_id)
@@ -4113,6 +4117,7 @@
   if (version_.transport_version == QUIC_VERSION_99) {
     return;
   }
+  SetDecrypterLevel(ENCRYPTION_FORWARD_SECURE);
   // clang-format off
   unsigned char packet[] = {
     // public flags (8 byte connection_id)
@@ -4509,6 +4514,7 @@
     // This frame is not supported in version 99.
     return;
   }
+  SetDecrypterLevel(ENCRYPTION_FORWARD_SECURE);
   // clang-format off
   PacketFragments packet = {
       // public flags (8 byte connection_id)
@@ -4634,6 +4640,7 @@
     // for Version 99 equivalents.
     return;
   }
+  SetDecrypterLevel(ENCRYPTION_FORWARD_SECURE);
   // clang-format off
   PacketFragments packet = {
       // public flags (8 byte connection_id)
@@ -9402,6 +9409,7 @@
     // effectively unlimited
     return;
   }
+  SetDecrypterLevel(ENCRYPTION_FORWARD_SECURE);
 
   QuicPacketHeader header;
   header.destination_connection_id = FramerTestConnectionId();
@@ -9441,6 +9449,7 @@
     // effectively unlimited
     return;
   }
+  SetDecrypterLevel(ENCRYPTION_FORWARD_SECURE);
 
   QuicPacketHeader header;
   header.destination_connection_id = FramerTestConnectionId();
@@ -9481,6 +9490,7 @@
     // effectively unlimited
     return;
   }
+  SetDecrypterLevel(ENCRYPTION_FORWARD_SECURE);
 
   QuicPacketHeader header;
   header.destination_connection_id = FramerTestConnectionId();
@@ -9758,12 +9768,12 @@
 // Verify that the packet returned by ConstructMisFramedEncryptedPacket()
 // does cause the framer to return an error.
 TEST_P(QuicFramerTest, ConstructMisFramedEncryptedPacket) {
-  SetDecrypterLevel(ENCRYPTION_FORWARD_SECURE);
   // Since we are using ConstructEncryptedPacket, we have to set the framer's
   // crypto to be Null.
   if (framer_.version().KnowsWhichDecrypterToUse()) {
-    framer_.InstallDecrypter(ENCRYPTION_INITIAL, QuicMakeUnique<NullDecrypter>(
-                                                     framer_.perspective()));
+    framer_.InstallDecrypter(
+        ENCRYPTION_FORWARD_SECURE,
+        QuicMakeUnique<NullDecrypter>(framer_.perspective()));
   } else {
     framer_.SetDecrypter(ENCRYPTION_INITIAL,
                          QuicMakeUnique<NullDecrypter>(framer_.perspective()));
@@ -13077,17 +13087,33 @@
     {"Unable to read protocol version.",
      {QUIC_VERSION_BYTES}},
     // connection_id length
+    {"Illegal long header type value.",
+     {0x00}},
+  };
+  // clang-format on
+
+  // clang-format off
+  PacketFragments packet45 = {
+    // public flags (IETF Retry packet, 0-length original destination CID)
+    {"Unable to read type.",
+     {0xf0}},
+    // version tag
+    {"Unable to read protocol version.",
+     {QUIC_VERSION_BYTES}},
+    // connection_id length
     {"Not yet supported IETF RETRY packet received.",
      {0x00}},
   };
   // clang-format on
 
+  PacketFragments& fragments =
+      framer_.transport_version() > QUIC_VERSION_44 ? packet45 : packet;
   std::unique_ptr<QuicEncryptedPacket> encrypted(
-      AssemblePacketFromFragments(packet));
+      AssemblePacketFromFragments(fragments));
 
   EXPECT_FALSE(framer_.ProcessPacket(*encrypted));
   EXPECT_EQ(QUIC_INVALID_PACKET_HEADER, framer_.error());
-  CheckFramingBoundaries(packet, QUIC_INVALID_PACKET_HEADER);
+  CheckFramingBoundaries(fragments, QUIC_INVALID_PACKET_HEADER);
 }
 
 TEST_P(QuicFramerTest, RetryPacketRejectedWithMultiplePacketNumberSpaces) {

quic/core/quic_versions.cc

diff --git a/quic/core/quic_versions.cc b/quic/core/quic_versions.cc
index a5f1f41..a6d237e 100644
--- a/quic/core/quic_versions.cc
+++ b/quic/core/quic_versions.cc
@@ -38,7 +38,9 @@
 }
 
 bool ParsedQuicVersion::KnowsWhichDecrypterToUse() const {
-  return transport_version == QUIC_VERSION_99 ||
+  return (GetQuicReloadableFlag(quic_v44_disable_trial_decryption) &&
+          transport_version >= QUIC_VERSION_44) ||
+         transport_version == QUIC_VERSION_99 ||
          handshake_protocol == PROTOCOL_TLS1_3;
 }