tdesktop/Telegram/SourceFiles/mtproto/auth_key.h

151 lines
4.7 KiB
C++

/*
This file is part of Telegram Desktop,
the official desktop application for the Telegram messaging service.
For license and copyright information please follow this link:
https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL
*/
#pragma once
#include <array>
#include <memory>
namespace MTP {
class AuthKey {
public:
static constexpr auto kSize = 256; // 2048 bits.
using Data = std::array<gsl::byte, kSize>;
using KeyId = uint64;
enum class Type {
Generated,
ReadFromFile,
Local,
};
AuthKey(Type type, DcId dcId, const Data &data) : _type(type), _dcId(dcId), _key(data) {
countKeyId();
}
AuthKey(const Data &data) : _type(Type::Local), _key(data) {
countKeyId();
}
AuthKey(const AuthKey &other) = delete;
AuthKey &operator=(const AuthKey &other) = delete;
Type type() const {
return _type;
}
int dcId() const {
return _dcId;
}
KeyId keyId() const {
return _keyId;
}
void prepareAES_oldmtp(const MTPint128 &msgKey, MTPint256 &aesKey, MTPint256 &aesIV, bool send) const;
void prepareAES(const MTPint128 &msgKey, MTPint256 &aesKey, MTPint256 &aesIV, bool send) const;
const void *partForMsgKey(bool send) const {
return _key.data() + 88 + (send ? 0 : 8);
}
void write(QDataStream &to) const {
to.writeRawData(reinterpret_cast<const char*>(_key.data()), _key.size());
}
bool equals(const std::shared_ptr<AuthKey> &other) const {
return other ? (_key == other->_key) : false;
}
static void FillData(Data &authKey, bytes::const_span computedAuthKey) {
auto computedAuthKeySize = computedAuthKey.size();
Assert(computedAuthKeySize <= kSize);
auto authKeyBytes = gsl::make_span(authKey);
if (computedAuthKeySize < kSize) {
bytes::set_with_const(authKeyBytes.subspan(0, kSize - computedAuthKeySize), gsl::byte());
bytes::copy(authKeyBytes.subspan(kSize - computedAuthKeySize), computedAuthKey);
} else {
bytes::copy(authKeyBytes, computedAuthKey);
}
}
private:
void countKeyId() {
auto sha1 = hashSha1(_key.data(), _key.size());
// Lower 64 bits = 8 bytes of 20 byte SHA1 hash.
_keyId = *reinterpret_cast<KeyId*>(sha1.data() + 12);
}
Type _type = Type::Generated;
DcId _dcId = 0;
Data _key = { { gsl::byte{} } };
KeyId _keyId = 0;
};
using AuthKeyPtr = std::shared_ptr<AuthKey>;
using AuthKeysList = std::vector<AuthKeyPtr>;
void aesIgeEncryptRaw(const void *src, void *dst, uint32 len, const void *key, const void *iv);
void aesIgeDecryptRaw(const void *src, void *dst, uint32 len, const void *key, const void *iv);
inline void aesIgeEncrypt_oldmtp(const void *src, void *dst, uint32 len, const AuthKeyPtr &authKey, const MTPint128 &msgKey) {
MTPint256 aesKey, aesIV;
authKey->prepareAES_oldmtp(msgKey, aesKey, aesIV, true);
return aesIgeEncryptRaw(src, dst, len, static_cast<const void*>(&aesKey), static_cast<const void*>(&aesIV));
}
inline void aesIgeEncrypt(const void *src, void *dst, uint32 len, const AuthKeyPtr &authKey, const MTPint128 &msgKey) {
MTPint256 aesKey, aesIV;
authKey->prepareAES(msgKey, aesKey, aesIV, true);
return aesIgeEncryptRaw(src, dst, len, static_cast<const void*>(&aesKey), static_cast<const void*>(&aesIV));
}
inline void aesEncryptLocal(const void *src, void *dst, uint32 len, const AuthKeyPtr &authKey, const void *key128) {
MTPint256 aesKey, aesIV;
authKey->prepareAES_oldmtp(*(const MTPint128*)key128, aesKey, aesIV, false);
return aesIgeEncryptRaw(src, dst, len, static_cast<const void*>(&aesKey), static_cast<const void*>(&aesIV));
}
inline void aesIgeDecrypt_oldmtp(const void *src, void *dst, uint32 len, const AuthKeyPtr &authKey, const MTPint128 &msgKey) {
MTPint256 aesKey, aesIV;
authKey->prepareAES_oldmtp(msgKey, aesKey, aesIV, false);
return aesIgeDecryptRaw(src, dst, len, static_cast<const void*>(&aesKey), static_cast<const void*>(&aesIV));
}
inline void aesIgeDecrypt(const void *src, void *dst, uint32 len, const AuthKeyPtr &authKey, const MTPint128 &msgKey) {
MTPint256 aesKey, aesIV;
authKey->prepareAES(msgKey, aesKey, aesIV, false);
return aesIgeDecryptRaw(src, dst, len, static_cast<const void*>(&aesKey), static_cast<const void*>(&aesIV));
}
inline void aesDecryptLocal(const void *src, void *dst, uint32 len, const AuthKeyPtr &authKey, const void *key128) {
MTPint256 aesKey, aesIV;
authKey->prepareAES_oldmtp(*(const MTPint128*)key128, aesKey, aesIV, false);
return aesIgeDecryptRaw(src, dst, len, static_cast<const void*>(&aesKey), static_cast<const void*>(&aesIV));
}
// ctr used inplace, encrypt the data and leave it at the same place
struct CTRState {
static constexpr int KeySize = 32;
static constexpr int IvecSize = 16;
static constexpr int EcountSize = 16;
uchar ivec[IvecSize] = { 0 };
uint32 num = 0;
uchar ecount[EcountSize] = { 0 };
};
void aesCtrEncrypt(void *data, uint32 len, const void *key, CTRState *state);
} // namespace MTP