// Copyright (c) 2012 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#ifndef NET_QUIC_CRYPTO_CRYPTO_PROTOCOL_H_
#define NET_QUIC_CRYPTO_CRYPTO_PROTOCOL_H_
#include <string>
#include "net/base/net_export.h"
#include "net/quic/quic_protocol.h"
// 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, we need
// to reverse the order of the bytes.
//
// We use a macro to ensure that no static initialisers are created. Use the
// MakeQuicTag function in normal code.
#define TAG(a, b, c, d) ((d << 24) + (c << 16) + (b << 8) + a)
namespace net {
typedef std::string ServerConfigID;
const QuicTag kCHLO = TAG('C', 'H', 'L', 'O'); // Client hello
const QuicTag kSHLO = TAG('S', 'H', 'L', 'O'); // Server hello
const QuicTag kSCFG = TAG('S', 'C', 'F', 'G'); // Server config
const QuicTag kREJ = TAG('R', 'E', 'J', '\0'); // Reject
const QuicTag kCETV = TAG('C', 'E', 'T', 'V'); // Client encrypted tag-value
// pairs
const QuicTag kPRST = TAG('P', 'R', 'S', 'T'); // Public reset
// Key exchange methods
const QuicTag kP256 = TAG('P', '2', '5', '6'); // ECDH, Curve P-256
const QuicTag kC255 = TAG('C', '2', '5', '5'); // ECDH, Curve25519
// AEAD algorithms
const QuicTag kNULL = TAG('N', 'U', 'L', 'N'); // null algorithm
const QuicTag kAESG = TAG('A', 'E', 'S', 'G'); // AES128 + GCM-12
const QuicTag kCC12 = TAG('C', 'C', '1', '2'); // ChaCha20 + Poly1305
// Congestion control feedback types
const QuicTag kQBIC = TAG('Q', 'B', 'I', 'C'); // TCP cubic
const QuicTag kPACE = TAG('P', 'A', 'C', 'E'); // Paced TCP cubic
const QuicTag kINAR = TAG('I', 'N', 'A', 'R'); // Inter arrival
// Congestion control options
const QuicTag kTBBR = TAG('T', 'B', 'B', 'R'); // Reduced Buffer Bloat TCP
// Loss detection algorithm types
const QuicTag kNACK = TAG('N', 'A', 'C', 'K'); // TCP style nack counting
const QuicTag kTIME = TAG('T', 'I', 'M', 'E'); // Time based
// Proof types (i.e. certificate types)
// NOTE: although it would be silly to do so, specifying both kX509 and kX59R
// is allowed and is equivalent to specifying only kX509.
const QuicTag kX509 = TAG('X', '5', '0', '9'); // X.509 certificate, all key
// types
const QuicTag kX59R = TAG('X', '5', '9', 'R'); // X.509 certificate, RSA keys
// only
const QuicTag kCHID = TAG('C', 'H', 'I', 'D'); // Channel ID.
// Client hello tags
const QuicTag kVER = TAG('V', 'E', 'R', '\0'); // Version (new)
const QuicTag kNONC = TAG('N', 'O', 'N', 'C'); // The client's nonce
const QuicTag kKEXS = TAG('K', 'E', 'X', 'S'); // Key exchange methods
const QuicTag kAEAD = TAG('A', 'E', 'A', 'D'); // Authenticated
// encryption algorithms
const QuicTag kCGST = TAG('C', 'G', 'S', 'T'); // Congestion control
// feedback types
const QuicTag kCOPT = TAG('C', 'O', 'P', 'T'); // Congestion control options
// kLOSS was 'L', 'O', 'S', 'S', but was changed from a tag vector to a tag.
const QuicTag kLOSS = TAG('L', 'O', 'S', 'A'); // Loss detection algorithms
const QuicTag kICSL = TAG('I', 'C', 'S', 'L'); // Idle connection state
// lifetime
const QuicTag kKATO = TAG('K', 'A', 'T', 'O'); // Keepalive timeout
const QuicTag kMSPC = TAG('M', 'S', 'P', 'C'); // Max streams per connection.
const QuicTag kIRTT = TAG('I', 'R', 'T', 'T'); // Estimated initial RTT in us.
const QuicTag kSWND = TAG('S', 'W', 'N', 'D'); // Server's Initial congestion
// window.
const QuicTag kSNI = TAG('S', 'N', 'I', '\0'); // Server name
// indication
const QuicTag kPUBS = TAG('P', 'U', 'B', 'S'); // Public key values
const QuicTag kSCID = TAG('S', 'C', 'I', 'D'); // Server config id
const QuicTag kORBT = TAG('O', 'B', 'I', 'T'); // Server orbit.
const QuicTag kPDMD = TAG('P', 'D', 'M', 'D'); // Proof demand.
const QuicTag kPROF = TAG('P', 'R', 'O', 'F'); // Proof (signature).
const QuicTag kCCS = TAG('C', 'C', 'S', 0); // Common certificate set
const QuicTag kCCRT = TAG('C', 'C', 'R', 'T'); // Cached certificate
const QuicTag kEXPY = TAG('E', 'X', 'P', 'Y'); // Expiry
// TODO(rjshade): Remove kIFCW when removing QUIC_VERSION_19.
const QuicTag kIFCW = TAG('I', 'F', 'C', 'W'); // Initial flow control receive
// window.
const QuicTag kSFCW = TAG('S', 'F', 'C', 'W'); // Initial stream flow control
// receive window.
const QuicTag kCFCW = TAG('C', 'F', 'C', 'W'); // Initial session/connection
// flow control receive window.
const QuicTag kUAID = TAG('U', 'A', 'I', 'D'); // Client's User Agent ID.
// Server hello tags
const QuicTag kCADR = TAG('C', 'A', 'D', 'R'); // Client IP address and port
// CETV tags
const QuicTag kCIDK = TAG('C', 'I', 'D', 'K'); // ChannelID key
const QuicTag kCIDS = TAG('C', 'I', 'D', 'S'); // ChannelID signature
// Public reset tags
const QuicTag kRNON = TAG('R', 'N', 'O', 'N'); // Public reset nonce proof
const QuicTag kRSEQ = TAG('R', 'S', 'E', 'Q'); // Rejected sequence number
// Universal tags
const QuicTag kPAD = TAG('P', 'A', 'D', '\0'); // Padding
// Reasons for server sending rejection message tag.
const QuicTag kRREJ = TAG('R', 'R', 'E', 'J');
// These tags have a special form so that they appear either at the beginning
// or the end of a handshake message. Since handshake messages are sorted by
// tag value, the tags with 0 at the end will sort first and those with 255 at
// the end will sort last.
//
// The certificate chain should have a tag that will cause it to be sorted at
// the end of any handshake messages because it's likely to be large and the
// client might be able to get everything that it needs from the small values at
// the beginning.
//
// Likewise tags with random values should be towards the beginning of the
// message because the server mightn't hold state for a rejected client hello
// and therefore the client may have issues reassembling the rejection message
// in the event that it sent two client hellos.
const QuicTag kServerNonceTag =
TAG('S', 'N', 'O', 0); // The server's nonce
const QuicTag kSourceAddressTokenTag =
TAG('S', 'T', 'K', 0); // Source-address token
const QuicTag kCertificateTag =
TAG('C', 'R', 'T', 255); // Certificate chain
#undef TAG
const size_t kMaxEntries = 128; // Max number of entries in a message.
const size_t kNonceSize = 32; // Size in bytes of the connection nonce.
const size_t kOrbitSize = 8; // Number of bytes in an orbit value.
// kProofSignatureLabel is prepended to server configs before signing to avoid
// any cross-protocol attacks on the signature.
const char kProofSignatureLabel[] = "QUIC server config signature";
// kClientHelloMinimumSize is the minimum size of a client hello. Client hellos
// will have PAD tags added in order to ensure this minimum is met and client
// hellos smaller than this will be an error. This minimum size reduces the
// amplification factor of any mirror DoS attack.
//
// A client may pad an inchoate client hello to a size larger than
// kClientHelloMinimumSize to make it more likely to receive a complete
// rejection message.
const size_t kClientHelloMinimumSize = 1024;
} // namespace net
#endif // NET_QUIC_CRYPTO_CRYPTO_PROTOCOL_H_