Landing Recent QUIC changes until Mon Nov 14 04:43:50 2016 +0000

net/quic/core/quic_protocol.h

Index: net/quic/core/quic_protocol.h
diff --git a/net/quic/core/quic_protocol.h b/net/quic/core/quic_protocol.h
index 624e48b0078e91076c2ed450439b91f6e6aa7838..fc5042d9db5dde7ba4dfc1eb5f2fed6a40960ddb 100644
--- a/net/quic/core/quic_protocol.h
+++ b/net/quic/core/quic_protocol.h
@@ -29,402 +29,17 @@
 #include "net/base/net_export.h"
 #include "net/quic/core/interval_set.h"
 #include "net/quic/core/quic_bandwidth.h"
+#include "net/quic/core/quic_buffer_allocator.h"
+#include "net/quic/core/quic_constants.h"
+#include "net/quic/core/quic_error_codes.h"
 #include "net/quic/core/quic_time.h"
 #include "net/quic/core/quic_types.h"
+#include "net/quic/core/quic_versions.h"
 
 namespace net {
 
 class QuicPacket;
 struct QuicPacketHeader;
-class QuicAckListenerInterface;
-
-typedef uint64_t QuicConnectionId;
-typedef uint32_t QuicStreamId;
-typedef uint64_t QuicStreamOffset;
-typedef uint64_t QuicPacketNumber;
-typedef uint8_t QuicPathId;
-typedef uint64_t QuicPublicResetNonceProof;
-typedef uint8_t QuicPacketEntropyHash;
-typedef uint32_t QuicHeaderId;
-// QuicTag is the type of a tag in the wire protocol.
-typedef uint32_t QuicTag;
-typedef std::vector<QuicTag> QuicTagVector;
-typedef std::map<QuicTag, std::string> QuicTagValueMap;
-typedef uint16_t QuicPacketLength;
-
-// Default initial maximum size in bytes of a QUIC packet.
-const QuicByteCount kDefaultMaxPacketSize = 1350;
-// Default initial maximum size in bytes of a QUIC packet for servers.
-const QuicByteCount kDefaultServerMaxPacketSize = 1000;
-// The maximum packet size of any QUIC packet, based on ethernet's max size,
-// minus the IP and UDP headers. IPv6 has a 40 byte header, UDP adds an
-// additional 8 bytes.  This is a total overhead of 48 bytes.  Ethernet's
-// max packet size is 1500 bytes,  1500 - 48 = 1452.
-const QuicByteCount kMaxPacketSize = 1452;
-// Default maximum packet size used in the Linux TCP implementation.
-// Used in QUIC for congestion window computations in bytes.
-const QuicByteCount kDefaultTCPMSS = 1460;
-
-// We match SPDY's use of 32 (since we'd compete with SPDY).
-const QuicPacketCount kInitialCongestionWindow = 32;
-
-// Minimum size of initial flow control window, for both stream and session.
-const uint32_t kMinimumFlowControlSendWindow = 16 * 1024;  // 16 KB
-
-// Maximum flow control receive window limits for connection and stream.
-const QuicByteCount kStreamReceiveWindowLimit = 16 * 1024 * 1024;   // 16 MB
-const QuicByteCount kSessionReceiveWindowLimit = 24 * 1024 * 1024;  // 24 MB
-
-// Default limit on the size of uncompressed headers.
-const QuicByteCount kDefaultMaxUncompressedHeaderSize = 16 * 1024;  // 16 KB
-
-// Minimum size of the CWND, in packets, when doing bandwidth resumption.
-const QuicPacketCount kMinCongestionWindowForBandwidthResumption = 10;
-
-// Maximum number of tracked packets.
-const QuicPacketCount kMaxTrackedPackets = 10000;
-
-// Default size of the socket receive buffer in bytes.
-const QuicByteCount kDefaultSocketReceiveBuffer = 1024 * 1024;
-
-// Don't allow a client to suggest an RTT shorter than 10ms.
-const uint32_t kMinInitialRoundTripTimeUs = 10 * kNumMicrosPerMilli;
-
-// Don't allow a client to suggest an RTT longer than 15 seconds.
-const uint32_t kMaxInitialRoundTripTimeUs = 15 * kNumMicrosPerSecond;
-
-// Maximum number of open streams per connection.
-const size_t kDefaultMaxStreamsPerConnection = 100;
-
-// Number of bytes reserved for public flags in the packet header.
-const size_t kPublicFlagsSize = 1;
-// Number of bytes reserved for version number in the packet header.
-const size_t kQuicVersionSize = 4;
-// Number of bytes reserved for path id in the packet header.
-const size_t kQuicPathIdSize = 1;
-// Number of bytes reserved for private flags in the packet header.
-const size_t kPrivateFlagsSize = 1;
-
-// Signifies that the QuicPacket will contain version of the protocol.
-const bool kIncludeVersion = true;
-// Signifies that the QuicPacket will contain path id.
-const bool kIncludePathId = true;
-// Signifies that the QuicPacket will include a diversification nonce.
-const bool kIncludeDiversificationNonce = true;
-
-// Stream ID is reserved to denote an invalid ID.
-const QuicStreamId kInvalidStreamId = 0;
-
-// Reserved ID for the crypto stream.
-const QuicStreamId kCryptoStreamId = 1;
-
-// Reserved ID for the headers stream.
-const QuicStreamId kHeadersStreamId = 3;
-
-// Header key used to identify final offset on data stream when sending HTTP/2
-// trailing headers over QUIC.
-NET_EXPORT_PRIVATE extern const char* const kFinalOffsetHeaderKey;
-
-// Maximum delayed ack time, in ms.
-const int64_t kMaxDelayedAckTimeMs = 25;
-
-// Minimum tail loss probe time in ms.
-static const int64_t kMinTailLossProbeTimeoutMs = 10;
-
-// The timeout before the handshake succeeds.
-const int64_t kInitialIdleTimeoutSecs = 5;
-// The default idle timeout.
-const int64_t kDefaultIdleTimeoutSecs = 30;
-// The maximum idle timeout that can be negotiated.
-const int64_t kMaximumIdleTimeoutSecs = 60 * 10;  // 10 minutes.
-// The default timeout for a connection until the crypto handshake succeeds.
-const int64_t kMaxTimeForCryptoHandshakeSecs = 10;  // 10 secs.
-
-// Default limit on the number of undecryptable packets the connection buffers
-// before the CHLO/SHLO arrive.
-const size_t kDefaultMaxUndecryptablePackets = 10;
-
-// Default ping timeout.
-const int64_t kPingTimeoutSecs = 15;  // 15 secs.
-
-// Minimum number of RTTs between Server Config Updates (SCUP) sent to client.
-const int kMinIntervalBetweenServerConfigUpdatesRTTs = 10;
-
-// Minimum time between Server Config Updates (SCUP) sent to client.
-const int kMinIntervalBetweenServerConfigUpdatesMs = 1000;
-
-// Minimum number of packets between Server Config Updates (SCUP).
-const int kMinPacketsBetweenServerConfigUpdates = 100;
-
-// The number of open streams that a server will accept is set to be slightly
-// larger than the negotiated limit. Immediately closing the connection if the
-// client opens slightly too many streams is not ideal: the client may have sent
-// a FIN that was lost, and simultaneously opened a new stream. The number of
-// streams a server accepts is a fixed increment over the negotiated limit, or a
-// percentage increase, whichever is larger.
-const float kMaxStreamsMultiplier = 1.1f;
-const int kMaxStreamsMinimumIncrement = 10;
-
-// Available streams are ones with IDs less than the highest stream that has
-// been opened which have neither been opened or reset. The limit on the number
-// of available streams is 10 times the limit on the number of open streams.
-const int kMaxAvailableStreamsMultiplier = 10;
-
-// Track the number of promises that are not yet claimed by a
-// corresponding get.  This must be smaller than
-// kMaxAvailableStreamsMultiplier, because RST on a promised stream my
-// create available streams entries.
-const int kMaxPromisedStreamsMultiplier = kMaxAvailableStreamsMultiplier - 1;
-
-// TCP RFC calls for 1 second RTO however Linux differs from this default and
-// define the minimum RTO to 200ms, we will use the same until we have data to
-// support a higher or lower value.
-static const int64_t kMinRetransmissionTimeMs = 200;
-
-// We define an unsigned 16-bit floating point value, inspired by IEEE floats
-// (http://en.wikipedia.org/wiki/Half_precision_floating-point_format),
-// with 5-bit exponent (bias 1), 11-bit mantissa (effective 12 with hidden
-// bit) and denormals, but without signs, transfinites or fractions. Wire format
-// 16 bits (little-endian byte order) are split into exponent (high 5) and
-// mantissa (low 11) and decoded as:
-//   uint64_t value;
-//   if (exponent == 0) value = mantissa;
-//   else value = (mantissa | 1 << 11) << (exponent - 1)
-const int kUFloat16ExponentBits = 5;
-const int kUFloat16MaxExponent = (1 << kUFloat16ExponentBits) - 2;     // 30
-const int kUFloat16MantissaBits = 16 - kUFloat16ExponentBits;          // 11
-const int kUFloat16MantissaEffectiveBits = kUFloat16MantissaBits + 1;  // 12
-const uint64_t kUFloat16MaxValue =  // 0x3FFC0000000
-    ((UINT64_C(1) << kUFloat16MantissaEffectiveBits) - 1)
-    << kUFloat16MaxExponent;
-
-// Default path ID.
-const QuicPathId kDefaultPathId = 0;
-// Invalid path ID.
-const QuicPathId kInvalidPathId = 0xff;
-
-// kDiversificationNonceSize is the size, in bytes, of the nonce that a server
-// may set in the packet header to ensure that its INITIAL keys are not
-// duplicated.
-const size_t kDiversificationNonceSize = 32;
-
-// The largest gap in packets we'll accept without closing the connection.
-// This will likely have to be tuned.
-const QuicPacketNumber kMaxPacketGap = 5000;
-
-enum TransmissionType : int8_t {
-  NOT_RETRANSMISSION,
-  FIRST_TRANSMISSION_TYPE = NOT_RETRANSMISSION,
-  HANDSHAKE_RETRANSMISSION,    // Retransmits due to handshake timeouts.
-  ALL_UNACKED_RETRANSMISSION,  // Retransmits all unacked packets.
-  ALL_INITIAL_RETRANSMISSION,  // Retransmits all initially encrypted packets.
-  LOSS_RETRANSMISSION,         // Retransmits due to loss detection.
-  RTO_RETRANSMISSION,          // Retransmits due to retransmit time out.
-  TLP_RETRANSMISSION,          // Tail loss probes.
-  LAST_TRANSMISSION_TYPE = TLP_RETRANSMISSION,
-};
-
-enum HasRetransmittableData : int8_t {
-  NO_RETRANSMITTABLE_DATA,
-  HAS_RETRANSMITTABLE_DATA,
-};
-
-enum IsHandshake : int8_t { NOT_HANDSHAKE, IS_HANDSHAKE };
-
-enum class Perspective { IS_SERVER, IS_CLIENT };
-
-// Describes whether a ConnectionClose was originated by the peer.
-enum class ConnectionCloseSource { FROM_PEER, FROM_SELF };
-
-// Should a connection be closed silently or not.
-enum class ConnectionCloseBehavior {
-  SILENT_CLOSE,
-  SEND_CONNECTION_CLOSE_PACKET,
-  SEND_CONNECTION_CLOSE_PACKET_WITH_NO_ACK
-};
-
-NET_EXPORT_PRIVATE std::ostream& operator<<(std::ostream& os,
-                                            const Perspective& s);
-enum QuicFrameType {
-  // Regular frame types. The values set here cannot change without the
-  // introduction of a new QUIC version.
-  PADDING_FRAME = 0,
-  RST_STREAM_FRAME = 1,
-  CONNECTION_CLOSE_FRAME = 2,
-  GOAWAY_FRAME = 3,
-  WINDOW_UPDATE_FRAME = 4,
-  BLOCKED_FRAME = 5,
-  STOP_WAITING_FRAME = 6,
-  PING_FRAME = 7,
-  PATH_CLOSE_FRAME = 8,
-
-  // STREAM and ACK frames are special frames. They are encoded differently on
-  // the wire and their values do not need to be stable.
-  STREAM_FRAME,
-  ACK_FRAME,
-  // The path MTU discovery frame is encoded as a PING frame on the wire.
-  MTU_DISCOVERY_FRAME,
-  NUM_FRAME_TYPES
-};
-
-enum QuicConnectionIdLength {
-  PACKET_0BYTE_CONNECTION_ID = 0,
-  PACKET_8BYTE_CONNECTION_ID = 8
-};
-
-enum QuicPacketNumberLength : int8_t {
-  PACKET_1BYTE_PACKET_NUMBER = 1,
-  PACKET_2BYTE_PACKET_NUMBER = 2,
-  PACKET_4BYTE_PACKET_NUMBER = 4,
-  PACKET_6BYTE_PACKET_NUMBER = 6
-};
-
-// Used to indicate a QuicSequenceNumberLength using two flag bits.
-enum QuicPacketNumberLengthFlags {
-  PACKET_FLAGS_1BYTE_PACKET = 0,           // 00
-  PACKET_FLAGS_2BYTE_PACKET = 1,           // 01
-  PACKET_FLAGS_4BYTE_PACKET = 1 << 1,      // 10
-  PACKET_FLAGS_6BYTE_PACKET = 1 << 1 | 1,  // 11
-};
-
-// The public flags are specified in one byte.
-enum QuicPacketPublicFlags {
-  PACKET_PUBLIC_FLAGS_NONE = 0,
-
-  // Bit 0: Does the packet header contains version info?
-  PACKET_PUBLIC_FLAGS_VERSION = 1 << 0,
-
-  // Bit 1: Is this packet a public reset packet?
-  PACKET_PUBLIC_FLAGS_RST = 1 << 1,
-
-  // Bit 2: indicates the that public header includes a nonce.
-  PACKET_PUBLIC_FLAGS_NONCE = 1 << 2,
-
-  // Bit 3: indicates whether a ConnectionID is included.
-  PACKET_PUBLIC_FLAGS_0BYTE_CONNECTION_ID = 0,
-  PACKET_PUBLIC_FLAGS_8BYTE_CONNECTION_ID = 1 << 3,
-
-  // QUIC_VERSION_32 and earlier use two bits for an 8 byte
-  // connection id.
-  PACKET_PUBLIC_FLAGS_8BYTE_CONNECTION_ID_OLD = 1 << 3 | 1 << 2,
-
-  // Bits 4 and 5 describe the packet number length as follows:
-  // --00----: 1 byte
-  // --01----: 2 bytes
-  // --10----: 4 bytes
-  // --11----: 6 bytes
-  PACKET_PUBLIC_FLAGS_1BYTE_PACKET = PACKET_FLAGS_1BYTE_PACKET << 4,
-  PACKET_PUBLIC_FLAGS_2BYTE_PACKET = PACKET_FLAGS_2BYTE_PACKET << 4,
-  PACKET_PUBLIC_FLAGS_4BYTE_PACKET = PACKET_FLAGS_4BYTE_PACKET << 4,
-  PACKET_PUBLIC_FLAGS_6BYTE_PACKET = PACKET_FLAGS_6BYTE_PACKET << 4,
-
-  // Bit 6: Does the packet header contain a path id?
-  PACKET_PUBLIC_FLAGS_MULTIPATH = 1 << 6,
-
-  // Reserved, unimplemented flags:
-
-  // Bit 7: indicates the presence of a second flags byte.
-  PACKET_PUBLIC_FLAGS_TWO_OR_MORE_BYTES = 1 << 7,
-
-  // All bits set (bit 7 is not currently used): 01111111
-  PACKET_PUBLIC_FLAGS_MAX = (1 << 7) - 1,
-};
-
-// The private flags are specified in one byte.
-enum QuicPacketPrivateFlags {
-  PACKET_PRIVATE_FLAGS_NONE = 0,
-
-  // Bit 0: Does this packet contain an entropy bit?
-  PACKET_PRIVATE_FLAGS_ENTROPY = 1 << 0,
-
-  // (bits 1-7 are not used): 00000001
-  PACKET_PRIVATE_FLAGS_MAX = (1 << 1) - 1
-};
-
-// The available versions of QUIC. Guaranteed that the integer value of the enum
-// will match the version number.
-// When adding a new version to this enum you should add it to
-// kSupportedQuicVersions (if appropriate), and also add a new case to the
-// helper methods QuicVersionToQuicTag, QuicTagToQuicVersion, and
-// QuicVersionToString.
-enum QuicVersion {
-  // Special case to indicate unknown/unsupported QUIC version.
-  QUIC_VERSION_UNSUPPORTED = 0,
-
-  QUIC_VERSION_32 = 32,  // FEC related fields are removed from wire format.
-  QUIC_VERSION_33 = 33,  // Adds diversification nonces.
-  QUIC_VERSION_34 = 34,  // Deprecates entropy, removes private flag from packet
-                         // header, uses new ack and stop waiting wire format.
-  QUIC_VERSION_35 = 35,  // Allows endpoints to independently set stream limit.
-  QUIC_VERSION_36 = 36,  // Add support to force HOL blocking.
-
-  // IMPORTANT: if you are adding to this std::list, follow the instructions at
-  // http://sites/quic/adding-and-removing-versions
-};
-
-// This vector contains QUIC versions which we currently support.
-// This should be ordered such that the highest supported version is the first
-// element, with subsequent elements in descending order (versions can be
-// skipped as necessary).
-//
-// IMPORTANT: if you are adding to this list, follow the instructions at
-// http://sites/quic/adding-and-removing-versions
-static const QuicVersion kSupportedQuicVersions[] = {
-    QUIC_VERSION_36, QUIC_VERSION_35, QUIC_VERSION_34, QUIC_VERSION_33,
-    QUIC_VERSION_32};
-
-typedef std::vector<QuicVersion> QuicVersionVector;
-
-// Returns a vector of QUIC versions in kSupportedQuicVersions.
-NET_EXPORT_PRIVATE QuicVersionVector AllSupportedVersions();
-
-// Returns a vector of QUIC versions from kSupportedQuicVersions which exclude
-// any versions which are disabled by flags.
-NET_EXPORT_PRIVATE QuicVersionVector CurrentSupportedVersions();
-
-// Returns a vector of QUIC versions from |versions| which exclude any versions
-// which are disabled by flags.
-NET_EXPORT_PRIVATE QuicVersionVector
-FilterSupportedVersions(QuicVersionVector versions);
-
-// Returns QUIC version of |index| in result of |versions|. Returns
-// QUIC_VERSION_UNSUPPORTED if |index| is out of bounds.
-NET_EXPORT_PRIVATE QuicVersionVector
-VersionOfIndex(const QuicVersionVector& versions, int index);
-
-// QuicTag is written to and read from the wire, but we prefer to use
-// the more readable QuicVersion at other levels.
-// Helper function which translates from a QuicVersion to a QuicTag. Returns 0
-// if QuicVersion is unsupported.
-NET_EXPORT_PRIVATE QuicTag QuicVersionToQuicTag(const QuicVersion version);
-
-// Returns appropriate QuicVersion from a QuicTag.
-// Returns QUIC_VERSION_UNSUPPORTED if version_tag cannot be understood.
-NET_EXPORT_PRIVATE QuicVersion QuicTagToQuicVersion(const QuicTag version_tag);
-
-// Helper function which translates from a QuicVersion to a string.
-// Returns strings corresponding to enum names (e.g. QUIC_VERSION_6).
-NET_EXPORT_PRIVATE std::string QuicVersionToString(const QuicVersion version);
-
-// Returns comma separated list of string representations of QuicVersion enum
-// values in the supplied |versions| vector.
-NET_EXPORT_PRIVATE std::string QuicVersionVectorToString(
-    const QuicVersionVector& versions);
-
-// Version and Crypto tags are written to the wire with a big-endian
-// representation of the name of the tag.  For example
-// the client hello tag (CHLO) will be written as the
-// following 4 bytes: 'C' 'H' 'L' 'O'.  Since it is
-// stored in memory as a little endian uint32_t, we need
-// to reverse the order of the bytes.
-
-// MakeQuicTag returns a value given the four bytes. For example:
-//   MakeQuicTag('C', 'H', 'L', 'O');
-NET_EXPORT_PRIVATE QuicTag MakeQuicTag(char a, char b, char c, char d);
-
-// Returns true if the tag vector contains the specified tag.
-NET_EXPORT_PRIVATE bool ContainsQuicTag(const QuicTagVector& tag_vector,
-                                        QuicTag tag);
 
 // Size in bytes of the data packet header.
 NET_EXPORT_PRIVATE size_t GetPacketHeaderSize(QuicVersion version,
@@ -450,273 +65,6 @@ GetStartOfEncryptedData(QuicVersion version,
                         bool include_diversification_nonce,
                         QuicPacketNumberLength packet_number_length);
 
-enum QuicRstStreamErrorCode {
-  // Complete response has been sent, sending a RST to ask the other endpoint
-  // to stop sending request data without discarding the response.
-  QUIC_STREAM_NO_ERROR = 0,
-
-  // There was some error which halted stream processing.
-  QUIC_ERROR_PROCESSING_STREAM,
-  // We got two fin or reset offsets which did not match.
-  QUIC_MULTIPLE_TERMINATION_OFFSETS,
-  // We got bad payload and can not respond to it at the protocol level.
-  QUIC_BAD_APPLICATION_PAYLOAD,
-  // Stream closed due to connection error. No reset frame is sent when this
-  // happens.
-  QUIC_STREAM_CONNECTION_ERROR,
-  // GoAway frame sent. No more stream can be created.
-  QUIC_STREAM_PEER_GOING_AWAY,
-  // The stream has been cancelled.
-  QUIC_STREAM_CANCELLED,
-  // Closing stream locally, sending a RST to allow for proper flow control
-  // accounting. Sent in response to a RST from the peer.
-  QUIC_RST_ACKNOWLEDGEMENT,
-  // Receiver refused to create the stream (because its limit on open streams
-  // has been reached).  The sender should retry the request later (using
-  // another stream).
-  QUIC_REFUSED_STREAM,
-  // Invalid URL in PUSH_PROMISE request header.
-  QUIC_INVALID_PROMISE_URL,
-  // Server is not authoritative for this URL.
-  QUIC_UNAUTHORIZED_PROMISE_URL,
-  // Can't have more than one active PUSH_PROMISE per URL.
-  QUIC_DUPLICATE_PROMISE_URL,
-  // Vary check failed.
-  QUIC_PROMISE_VARY_MISMATCH,
-  // Only GET and HEAD methods allowed.
-  QUIC_INVALID_PROMISE_METHOD,
-  // The push stream is unclaimed and timed out.
-  QUIC_PUSH_STREAM_TIMED_OUT,
-  // Received headers were too large.
-  QUIC_HEADERS_TOO_LARGE,
-  // No error. Used as bound while iterating.
-  QUIC_STREAM_LAST_ERROR,
-};
-// QUIC error codes are encoded to a single octet on-the-wire.
-static_assert(static_cast<int>(QUIC_STREAM_LAST_ERROR) <=
-                  std::numeric_limits<uint8_t>::max(),
-              "QuicErrorCode exceeds single octet");
-
-// These values must remain stable as they are uploaded to UMA histograms.
-// To add a new error code, use the current value of QUIC_LAST_ERROR and
-// increment QUIC_LAST_ERROR.
-enum QuicErrorCode {
-  QUIC_NO_ERROR = 0,
-
-  // Connection has reached an invalid state.
-  QUIC_INTERNAL_ERROR = 1,
-  // There were data frames after the a fin or reset.
-  QUIC_STREAM_DATA_AFTER_TERMINATION = 2,
-  // Control frame is malformed.
-  QUIC_INVALID_PACKET_HEADER = 3,
-  // Frame data is malformed.
-  QUIC_INVALID_FRAME_DATA = 4,
-  // The packet contained no payload.
-  QUIC_MISSING_PAYLOAD = 48,
-  // FEC data is malformed.
-  QUIC_INVALID_FEC_DATA = 5,
-  // STREAM frame data is malformed.
-  QUIC_INVALID_STREAM_DATA = 46,
-  // STREAM frame data overlaps with buffered data.
-  QUIC_OVERLAPPING_STREAM_DATA = 87,
-  // Received STREAM frame data is not encrypted.
-  QUIC_UNENCRYPTED_STREAM_DATA = 61,
-  // Attempt to send unencrypted STREAM frame.
-  QUIC_ATTEMPT_TO_SEND_UNENCRYPTED_STREAM_DATA = 88,
-  // Received a frame which is likely the result of memory corruption.
-  QUIC_MAYBE_CORRUPTED_MEMORY = 89,
-  // FEC frame data is not encrypted.
-  QUIC_UNENCRYPTED_FEC_DATA = 77,
-  // RST_STREAM frame data is malformed.
-  QUIC_INVALID_RST_STREAM_DATA = 6,
-  // CONNECTION_CLOSE frame data is malformed.
-  QUIC_INVALID_CONNECTION_CLOSE_DATA = 7,
-  // GOAWAY frame data is malformed.
-  QUIC_INVALID_GOAWAY_DATA = 8,
-  // WINDOW_UPDATE frame data is malformed.
-  QUIC_INVALID_WINDOW_UPDATE_DATA = 57,
-  // BLOCKED frame data is malformed.
-  QUIC_INVALID_BLOCKED_DATA = 58,
-  // STOP_WAITING frame data is malformed.
-  QUIC_INVALID_STOP_WAITING_DATA = 60,
-  // PATH_CLOSE frame data is malformed.
-  QUIC_INVALID_PATH_CLOSE_DATA = 78,
-  // ACK frame data is malformed.
-  QUIC_INVALID_ACK_DATA = 9,
-
-  // Version negotiation packet is malformed.
-  QUIC_INVALID_VERSION_NEGOTIATION_PACKET = 10,
-  // Public RST packet is malformed.
-  QUIC_INVALID_PUBLIC_RST_PACKET = 11,
-  // There was an error decrypting.
-  QUIC_DECRYPTION_FAILURE = 12,
-  // There was an error encrypting.
-  QUIC_ENCRYPTION_FAILURE = 13,
-  // The packet exceeded kMaxPacketSize.
-  QUIC_PACKET_TOO_LARGE = 14,
-  // The peer is going away.  May be a client or server.
-  QUIC_PEER_GOING_AWAY = 16,
-  // A stream ID was invalid.
-  QUIC_INVALID_STREAM_ID = 17,
-  // A priority was invalid.
-  QUIC_INVALID_PRIORITY = 49,
-  // Too many streams already open.
-  QUIC_TOO_MANY_OPEN_STREAMS = 18,
-  // The peer created too many available streams.
-  QUIC_TOO_MANY_AVAILABLE_STREAMS = 76,
-  // Received public reset for this connection.
-  QUIC_PUBLIC_RESET = 19,
-  // Invalid protocol version.
-  QUIC_INVALID_VERSION = 20,
-
-  // The Header ID for a stream was too far from the previous.
-  QUIC_INVALID_HEADER_ID = 22,
-  // Negotiable parameter received during handshake had invalid value.
-  QUIC_INVALID_NEGOTIATED_VALUE = 23,
-  // There was an error decompressing data.
-  QUIC_DECOMPRESSION_FAILURE = 24,
-  // The connection timed out due to no network activity.
-  QUIC_NETWORK_IDLE_TIMEOUT = 25,
-  // The connection timed out waiting for the handshake to complete.
-  QUIC_HANDSHAKE_TIMEOUT = 67,
-  // There was an error encountered migrating addresses.
-  QUIC_ERROR_MIGRATING_ADDRESS = 26,
-  // There was an error encountered migrating port only.
-  QUIC_ERROR_MIGRATING_PORT = 86,
-  // There was an error while writing to the socket.
-  QUIC_PACKET_WRITE_ERROR = 27,
-  // There was an error while reading from the socket.
-  QUIC_PACKET_READ_ERROR = 51,
-  // We received a STREAM_FRAME with no data and no fin flag set.
-  QUIC_EMPTY_STREAM_FRAME_NO_FIN = 50,
-  // We received invalid data on the headers stream.
-  QUIC_INVALID_HEADERS_STREAM_DATA = 56,
-  // The peer received too much data, violating flow control.
-  QUIC_FLOW_CONTROL_RECEIVED_TOO_MUCH_DATA = 59,
-  // The peer sent too much data, violating flow control.
-  QUIC_FLOW_CONTROL_SENT_TOO_MUCH_DATA = 63,
-  // The peer received an invalid flow control window.
-  QUIC_FLOW_CONTROL_INVALID_WINDOW = 64,
-  // The connection has been IP pooled into an existing connection.
-  QUIC_CONNECTION_IP_POOLED = 62,
-  // The connection has too many outstanding sent packets.
-  QUIC_TOO_MANY_OUTSTANDING_SENT_PACKETS = 68,
-  // The connection has too many outstanding received packets.
-  QUIC_TOO_MANY_OUTSTANDING_RECEIVED_PACKETS = 69,
-  // The quic connection has been cancelled.
-  QUIC_CONNECTION_CANCELLED = 70,
-  // Disabled QUIC because of high packet loss rate.
-  QUIC_BAD_PACKET_LOSS_RATE = 71,
-  // Disabled QUIC because of too many PUBLIC_RESETs post handshake.
-  QUIC_PUBLIC_RESETS_POST_HANDSHAKE = 73,
-  // Disabled QUIC because of too many timeouts with streams open.
-  QUIC_TIMEOUTS_WITH_OPEN_STREAMS = 74,
-  // Closed because we failed to serialize a packet.
-  QUIC_FAILED_TO_SERIALIZE_PACKET = 75,
-  // QUIC timed out after too many RTOs.
-  QUIC_TOO_MANY_RTOS = 85,
-
-  // Crypto errors.
-
-  // Hanshake failed.
-  QUIC_HANDSHAKE_FAILED = 28,
-  // Handshake message contained out of order tags.
-  QUIC_CRYPTO_TAGS_OUT_OF_ORDER = 29,
-  // Handshake message contained too many entries.
-  QUIC_CRYPTO_TOO_MANY_ENTRIES = 30,
-  // Handshake message contained an invalid value length.
-  QUIC_CRYPTO_INVALID_VALUE_LENGTH = 31,
-  // A crypto message was received after the handshake was complete.
-  QUIC_CRYPTO_MESSAGE_AFTER_HANDSHAKE_COMPLETE = 32,
-  // A crypto message was received with an illegal message tag.
-  QUIC_INVALID_CRYPTO_MESSAGE_TYPE = 33,
-  // A crypto message was received with an illegal parameter.
-  QUIC_INVALID_CRYPTO_MESSAGE_PARAMETER = 34,
-  // An invalid channel id signature was supplied.
-  QUIC_INVALID_CHANNEL_ID_SIGNATURE = 52,
-  // A crypto message was received with a mandatory parameter missing.
-  QUIC_CRYPTO_MESSAGE_PARAMETER_NOT_FOUND = 35,
-  // A crypto message was received with a parameter that has no overlap
-  // with the local parameter.
-  QUIC_CRYPTO_MESSAGE_PARAMETER_NO_OVERLAP = 36,
-  // A crypto message was received that contained a parameter with too few
-  // values.
-  QUIC_CRYPTO_MESSAGE_INDEX_NOT_FOUND = 37,
-  // A demand for an unsupport proof type was received.
-  QUIC_UNSUPPORTED_PROOF_DEMAND = 94,
-  // An internal error occured in crypto processing.
-  QUIC_CRYPTO_INTERNAL_ERROR = 38,
-  // A crypto handshake message specified an unsupported version.
-  QUIC_CRYPTO_VERSION_NOT_SUPPORTED = 39,
-  // A crypto handshake message resulted in a stateless reject.
-  QUIC_CRYPTO_HANDSHAKE_STATELESS_REJECT = 72,
-  // There was no intersection between the crypto primitives supported by the
-  // peer and ourselves.
-  QUIC_CRYPTO_NO_SUPPORT = 40,
-  // The server rejected our client hello messages too many times.
-  QUIC_CRYPTO_TOO_MANY_REJECTS = 41,
-  // The client rejected the server's certificate chain or signature.
-  QUIC_PROOF_INVALID = 42,
-  // A crypto message was received with a duplicate tag.
-  QUIC_CRYPTO_DUPLICATE_TAG = 43,
-  // A crypto message was received with the wrong encryption level (i.e. it
-  // should have been encrypted but was not.)
-  QUIC_CRYPTO_ENCRYPTION_LEVEL_INCORRECT = 44,
-  // The server config for a server has expired.
-  QUIC_CRYPTO_SERVER_CONFIG_EXPIRED = 45,
-  // We failed to setup the symmetric keys for a connection.
-  QUIC_CRYPTO_SYMMETRIC_KEY_SETUP_FAILED = 53,
-  // A handshake message arrived, but we are still validating the
-  // previous handshake message.
-  QUIC_CRYPTO_MESSAGE_WHILE_VALIDATING_CLIENT_HELLO = 54,
-  // A server config update arrived before the handshake is complete.
-  QUIC_CRYPTO_UPDATE_BEFORE_HANDSHAKE_COMPLETE = 65,
-  // CHLO cannot fit in one packet.
-  QUIC_CRYPTO_CHLO_TOO_LARGE = 90,
-  // This connection involved a version negotiation which appears to have been
-  // tampered with.
-  QUIC_VERSION_NEGOTIATION_MISMATCH = 55,
-
-  // Multipath errors.
-  // Multipath is not enabled, but a packet with multipath flag on is received.
-  QUIC_BAD_MULTIPATH_FLAG = 79,
-  // A path is supposed to exist but does not.
-  QUIC_MULTIPATH_PATH_DOES_NOT_EXIST = 91,
-  // A path is supposed to be active but is not.
-  QUIC_MULTIPATH_PATH_NOT_ACTIVE = 92,
-
-  // IP address changed causing connection close.
-  QUIC_IP_ADDRESS_CHANGED = 80,
-
-  // Connection migration errors.
-  // Network changed, but connection had no migratable streams.
-  QUIC_CONNECTION_MIGRATION_NO_MIGRATABLE_STREAMS = 81,
-  // Connection changed networks too many times.
-  QUIC_CONNECTION_MIGRATION_TOO_MANY_CHANGES = 82,
-  // Connection migration was attempted, but there was no new network to
-  // migrate to.
-  QUIC_CONNECTION_MIGRATION_NO_NEW_NETWORK = 83,
-  // Network changed, but connection had one or more non-migratable streams.
-  QUIC_CONNECTION_MIGRATION_NON_MIGRATABLE_STREAM = 84,
-
-  // Stream frames arrived too discontiguously so that stream sequencer buffer
-  // maintains too many gaps.
-  QUIC_TOO_MANY_FRAME_GAPS = 93,
-
-  // Sequencer buffer get into weird state where continuing read/write will lead
-  // to crash.
-  QUIC_STREAM_SEQUENCER_INVALID_STATE = 95,
-
-  // Connection closed because of server hits max number of sessions allowed.
-  // TODO(fayang): Add monitoring for QUIC_TOO_MANY_SESSIONS_ON_SERVER.
-  QUIC_TOO_MANY_SESSIONS_ON_SERVER = 96,
-
-  // No error. Used as bound while iterating.
-  QUIC_LAST_ERROR = 97,
-};
-
-typedef std::array<char, 32> DiversificationNonce;
-
 struct NET_EXPORT_PRIVATE QuicPacketPublicHeader {
   QuicPacketPublicHeader();
   explicit QuicPacketPublicHeader(const QuicPacketPublicHeader& other);
@@ -736,9 +84,6 @@ struct NET_EXPORT_PRIVATE QuicPacketPublicHeader {
   DiversificationNonce* nonce;
 };
 
-// An integer which cannot be a packet number.
-const QuicPacketNumber kInvalidPacketNumber = 0;
-
 // Header for Data packets.
 struct NET_EXPORT_PRIVATE QuicPacketHeader {
   QuicPacketHeader();
@@ -751,8 +96,6 @@ struct NET_EXPORT_PRIVATE QuicPacketHeader {
   QuicPacketPublicHeader public_header;
   QuicPacketNumber packet_number;
   QuicPathId path_id;
-  bool entropy_flag;
-  QuicPacketEntropyHash entropy_hash;
 };
 
 struct NET_EXPORT_PRIVATE QuicPublicResetPacket {
@@ -767,20 +110,6 @@ struct NET_EXPORT_PRIVATE QuicPublicResetPacket {
   IPEndPoint client_address;
 };
 
-enum QuicVersionNegotiationState {
-  START_NEGOTIATION = 0,
-  // Server-side this implies we've sent a version negotiation packet and are
-  // waiting on the client to select a compatible version.  Client-side this
-  // implies we've gotten a version negotiation packet, are retransmitting the
-  // initial packets with a supported version and are waiting for our first
-  // packet from the server.
-  NEGOTIATION_IN_PROGRESS,
-  // This indicates this endpoint has received a packet from the peer with a
-  // version this endpoint supports.  Version negotiation is complete, and the
-  // version number will no longer be sent with future packets.
-  NEGOTIATED_VERSION
-};
-
 typedef QuicPacketPublicHeader QuicVersionNegotiationPacket;
 
 // A padding frame contains no payload.
@@ -805,26 +134,6 @@ struct NET_EXPORT_PRIVATE QuicPingFrame {};
 // frame.
 struct NET_EXPORT_PRIVATE QuicMtuDiscoveryFrame {};
 
-class NET_EXPORT_PRIVATE QuicBufferAllocator {
- public:
-  virtual ~QuicBufferAllocator();
-
-  // Returns or allocates a new buffer of |size|. Never returns null.
-  virtual char* New(size_t size) = 0;
-
-  // Returns or allocates a new buffer of |size| if |flag_enable| is true.
-  // Otherwise, returns a buffer that is compatible with this class directly
-  // with operator new. Never returns null.
-  virtual char* New(size_t size, bool flag_enable) = 0;
-
-  // Releases a buffer.
-  virtual void Delete(char* buffer) = 0;
-
-  // Marks the allocator as being idle. Serves as a hint to notify the allocator
-  // that it should release any resources it's still holding on to.
-  virtual void MarkAllocatorIdle() {}
-};
-
 // Deleter for stream buffers. Copyable to support platforms where the deleter
 // of a unique_ptr must be copyable. Otherwise it would be nice for this to be
 // move-only.
@@ -897,9 +206,6 @@ struct NET_EXPORT_PRIVATE QuicStopWaitingFrame {
       const QuicStopWaitingFrame& s);
   // Path which this stop waiting frame belongs to.
   QuicPathId path_id;
-  // Entropy hash of all packets up to, but not including, the least unacked
-  // packet.
-  QuicPacketEntropyHash entropy_hash;
   // The lowest packet we've sent which is unacked, and we expect an ack for.
   QuicPacketNumber least_unacked;
 };
@@ -994,13 +300,6 @@ struct NET_EXPORT_PRIVATE QuicAckFrame {
                                                      const QuicAckFrame& s);
 
   // The highest packet number we've observed from the peer.
-  //
-  // In general, this should be the largest packet number we've received.  In
-  // the case of truncated acks, we may have to advertise a lower "upper bound"
-  // than largest received, to avoid implicitly acking missing packets that
-  // don't fit in the missing packet list due to size limitations.  In this
-  // case, largest_observed may be a packet which is also in the missing packets
-  // list.
   QuicPacketNumber largest_observed;
 
   // Time elapsed since largest_observed was received until this Ack frame was
@@ -1015,17 +314,6 @@ struct NET_EXPORT_PRIVATE QuicAckFrame {
 
   // Path which this ack belongs to.
   QuicPathId path_id;
-
-  // Entropy hash of all packets up to largest observed not including missing
-  // packets.
-  QuicPacketEntropyHash entropy_hash;
-
-  // Whether the ack had to be truncated when sent.
-  bool is_truncated;
-
-  // If true, |packets| express missing packets. Otherwise, |packets| express
-  // received packets.
-  bool missing;
 };
 
 // True if the packet number is greater than largest_observed or is listed
@@ -1036,25 +324,6 @@ IsAwaitingPacket(const QuicAckFrame& ack_frame,
                  QuicPacketNumber packet_number,
                  QuicPacketNumber peer_least_packet_awaiting_ack);
 
-// Defines for all types of congestion control algorithms that can be used in
-// QUIC. Note that this is separate from the congestion feedback type -
-// some congestion control algorithms may use the same feedback type
-// (Reno and Cubic are the classic example for that).
-enum CongestionControlType {
-  kCubic,
-  kCubicBytes,
-  kReno,
-  kRenoBytes,
-  kBBR,
-};
-
-enum LossDetectionType {
-  kNack,          // Used to mimic TCP's loss detection.
-  kTime,          // Time based loss detection.
-  kAdaptiveTime,  // Adaptive time based loss detection.
-  kLazyFack,      // Nack based but with FACK disabled for the first ack.
-};
-
 struct NET_EXPORT_PRIVATE QuicRstStreamFrame {
   QuicRstStreamFrame();
   QuicRstStreamFrame(QuicStreamId stream_id,
@@ -1155,35 +424,6 @@ struct NET_EXPORT_PRIVATE QuicPathCloseFrame {
   QuicPathId path_id;
 };
 
-// EncryptionLevel enumerates the stages of encryption that a QUIC connection
-// progresses through. When retransmitting a packet, the encryption level needs
-// to be specified so that it is retransmitted at a level which the peer can
-// understand.
-enum EncryptionLevel : int8_t {
-  ENCRYPTION_NONE = 0,
-  ENCRYPTION_INITIAL = 1,
-  ENCRYPTION_FORWARD_SECURE = 2,
-
-  NUM_ENCRYPTION_LEVELS,
-};
-
-enum PeerAddressChangeType {
-  // IP address and port remain unchanged.
-  NO_CHANGE,
-  // Port changed, but IP address remains unchanged.
-  PORT_CHANGE,
-  // IPv4 address changed, but within the /24 subnet (port may have changed.)
-  IPV4_SUBNET_CHANGE,
-  // IPv4 address changed, excluding /24 subnet change (port may have changed.)
-  IPV4_TO_IPV4_CHANGE,
-  // IP address change from an IPv4 to an IPv6 address (port may have changed.)
-  IPV4_TO_IPV6_CHANGE,
-  // IP address change from an IPv6 to an IPv4 address (port may have changed.)
-  IPV6_TO_IPV4_CHANGE,
-  // IP address change from an IPv6 to an IPv6 address (port may have changed.)
-  IPV6_TO_IPV6_CHANGE,
-};
-
 struct NET_EXPORT_PRIVATE QuicFrame {
   QuicFrame();
   explicit QuicFrame(QuicPaddingFrame padding_frame);
@@ -1376,17 +616,24 @@ class NET_EXPORT_PRIVATE QuicConnectionCloseDelegateInterface {
 class NET_EXPORT_PRIVATE QuicVersionManager {
  public:
   explicit QuicVersionManager(QuicVersionVector supported_versions);
-  ~QuicVersionManager();
+  virtual ~QuicVersionManager();
 
-  // Returns supported versions based on flags.
+  // Returns currently supported QUIC versions.
   const QuicVersionVector& GetSupportedVersions();
 
+ protected:
+  // Maybe refilter filtered_supported_versions_ based on flags.
+  void MaybeRefilterSupportedVersions();
+
+  // Refilters filtered_supported_versions_.
+  virtual void RefilterSupportedVersions();
+
+  const QuicVersionVector& filtered_supported_versions() const {
+    return filtered_supported_versions_;
+  }
+
  private:
-  // FLAGS_quic_disable_pre_34
-  bool disable_pre_34_;
-  // FLAGS_quic_enable_version_35
-  bool enable_version_35_;
-  // FLAGS_quic_enable_version_36_v2
+  // FLAGS_quic_enable_version_36_v3
   bool enable_version_36_;
   // The list of versions that may be supported.
   QuicVersionVector allowed_supported_versions_;
@@ -1411,7 +658,6 @@ struct NET_EXPORT_PRIVATE SerializedPacket {
                    QuicPacketNumberLength packet_number_length,
                    const char* encrypted_buffer,
                    QuicPacketLength encrypted_length,
-                   QuicPacketEntropyHash entropy_hash,
                    bool has_ack,
                    bool has_stop_waiting);
   SerializedPacket(const SerializedPacket& other);
@@ -1430,7 +676,6 @@ struct NET_EXPORT_PRIVATE SerializedPacket {
   QuicPacketNumber packet_number;
   QuicPacketNumberLength packet_number_length;
   EncryptionLevel encryption_level;
-  QuicPacketEntropyHash entropy_hash;
   bool has_ack;
   bool has_stop_waiting;
   TransmissionType transmission_type;
@@ -1512,17 +757,6 @@ struct PendingRetransmission {
   QuicPacketNumberLength packet_number_length;
 };
 
-// Convenience wrapper to wrap an iovec array and the total length, which must
-// be less than or equal to the actual total length of the iovecs.
-struct NET_EXPORT_PRIVATE QuicIOVector {
-  QuicIOVector(const struct iovec* iov, int iov_count, size_t total_length)
-      : iov(iov), iov_count(iov_count), total_length(total_length) {}
-
-  const struct iovec* iov;
-  const int iov_count;
-  const size_t total_length;
-};
-
 }  // namespace net
 
 #endif  // NET_QUIC_QUIC_PROTOCOL_H_