chromium/device/fido/cable/v2_constants.h

// Copyright 2020 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef DEVICE_FIDO_CABLE_V2_CONSTANTS_H_
#define DEVICE_FIDO_CABLE_V2_CONSTANTS_H_

#include "base/types/strong_alias.h"

namespace device {
namespace cablev2 {

namespace tunnelserver {

// KnownDomainID represents a tunnel server domain ID that maps to a known
// domain. IDs 0..256 are assigned and IDs 256..64K are hashed. Thus this type
// only contains values 256..64K or values that are assigned and the assignment
// is known in the code.
//
// Outside of tests, these values should only be created by |eid::ToComponents|
// or |tunnelserver::ToKnownTunnelID|.
KnownDomainID;

}  // namespace tunnelserver

// kAdvertSize is the number of bytes in an advert. This consists of a 16-byte
// UUID and a 4-byte UUID.
constexpr size_t kAdvertSize = …;
// kNonceSize is the number of bytes of nonce in the BLE advert.
constexpr size_t kNonceSize = …;
// kClientNonceSize is the number of bytes of nonce sent by the client, via the
// tunnel server, for a pairing-based handshake.
constexpr size_t kClientNonceSize = …;
// kRoutingIdSize is the number of bytes of routing information in the BLE
// advert.
constexpr size_t kRoutingIdSize = …;
// kTunnelIdSize is the number of bytes of opaque tunnel ID, used to identify a
// specific tunnel to the tunnel service.
constexpr size_t kTunnelIdSize = …;
// kEIDKeySize is the size of the key used to encrypt BLE adverts. This is a
// 256-bit AES key and a 256-bit HMAC key.
constexpr size_t kEIDKeySize = …;
// kPSKSize is the size of the Noise pre-shared key used in handshakes.
constexpr size_t kPSKSize = …;
// kRootSecretSize is the size of the main key maintained by authenticators.
constexpr size_t kRootSecretSize = …;
// kQRKeySize is the size of the private key data that generates a QR code. It
// consists of a 256-bit seed value that's used to genertate the P-256 private
// key and a 128-bit secret.
constexpr size_t kQRSecretSize = …;
constexpr size_t kQRSeedSize = …;
constexpr size_t kQRKeySize = …;
// kCompressedPublicKeySize is the size of a compressed X9.62 public key.
constexpr size_t kCompressedPublicKeySize = …/* type byte */ 1 + /* field element */ (256 / 8);
// kPairingIDSize is the number of bytes in the pairing ID that is shared after
// scanning a QR code.
constexpr size_t kPairingIDSize = …;
// kTunnelServer is the hardcoded tunnel server that phones will use for network
// communication. This specifies a Google service and the short domain seed is
// necessary to fit within a BLE advert.
constexpr auto kTunnelServer = …;
// kPostHandshakeMsgPaddingGranularity is the granularity of the padding added
// to the post-handshake message. This should be sufficiently large to pad away
// all information about the contents of this message.
constexpr size_t kPostHandshakeMsgPaddingGranularity = …;
// kMaxSyncInfoDaysForConsumer is the maximum age, in days, of sync info that
// consumers (i.e. desktops) will accept. Information in Sync's DeviceInfo
// records that is older than this will be ignored. This should be smaller than
// `kMaxSyncInfoDaysForProducer` so that the phone will always accept a
// connection.
constexpr unsigned kMaxSyncInfoDaysForConsumer = …;
// kMaxSyncInfoDaysForProducer is the maximum age, in days, of sync info that
// producers (i.e. phones) will accept. If a desktop tries to connect using
// information that was published before this time, the request will be
// rejected. This should be larger than `kMaxSyncInfoDaysForConsumer` so that
// this doesn't happen with honest clients.
constexpr unsigned kMaxSyncInfoDaysForProducer = …;

// MessageType enumerates the types of caBLEv2 messages on the wire.
enum class MessageType : uint8_t { … };

enum class Event { … };

// PayloadType enumerates the types of application-level payloads carried over a
// hybrid connection.
enum class PayloadType { … };

// Feature enumerates the features that a hybrid device can support.
enum class Feature { … };

}  // namespace cablev2
}  // namespace device

#endif  // DEVICE_FIDO_CABLE_V2_CONSTANTS_H_