tdesktop/Telegram/SourceFiles/mtproto/details/mtproto_serialized_request.cpp

157 lines
3.9 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
*/
#include "mtproto/details/mtproto_serialized_request.h"
#include "base/random.h"
namespace MTP::details {
namespace {
uint32 CountPaddingPrimesCount(
uint32 requestSize,
bool forAuthKeyInner) {
if (forAuthKeyInner) {
return ((8 + requestSize) & 0x03)
? (4 - ((8 + requestSize) & 0x03))
: 0;
}
auto result = ((8 + requestSize) & 0x03)
? (4 - ((8 + requestSize) & 0x03))
: 0;
// At least 12 bytes of random padding.
if (result < 3) {
result += 4;
}
// Some more random padding.
return result + ((base::RandomValue<uchar>() & 0x0F) << 2);
}
} // namespace
SerializedRequest::SerializedRequest(const RequestConstructHider::Tag &tag)
: _data(std::make_shared<RequestData>(tag)) {
}
SerializedRequest SerializedRequest::Prepare(
uint32 size,
uint32 reserveSize) {
Expects(size > 0);
const auto finalSize = std::max(size, reserveSize);
auto result = SerializedRequest(RequestConstructHider::Tag{});
result->reserve(kMessageBodyPosition + finalSize);
result->resize(kMessageBodyPosition);
result->back() = (size << 2);
result->lastSentTime = crl::now();
return result;
}
RequestData *SerializedRequest::operator->() const {
Expects(_data != nullptr);
return _data.get();
}
RequestData &SerializedRequest::operator*() const {
Expects(_data != nullptr);
return *_data;
}
SerializedRequest::operator bool() const {
return (_data != nullptr);
}
void SerializedRequest::setMsgId(mtpMsgId msgId) {
Expects(_data != nullptr);
Expects(_data->size() > kMessageBodyPosition);
memcpy(_data->data() + kMessageIdPosition, &msgId, sizeof(mtpMsgId));
}
mtpMsgId SerializedRequest::getMsgId() const {
Expects(_data != nullptr);
Expects(_data->size() > kMessageBodyPosition);
return *(mtpMsgId*)(_data->constData() + kMessageIdPosition);
}
void SerializedRequest::setSeqNo(uint32 seqNo) {
Expects(_data != nullptr);
Expects(_data->size() > kMessageBodyPosition);
(*_data)[kSeqNoPosition] = mtpPrime(seqNo);
}
uint32 SerializedRequest::getSeqNo() const {
Expects(_data != nullptr);
Expects(_data->size() > kMessageBodyPosition);
return uint32((*_data)[kSeqNoPosition]);
}
void SerializedRequest::addPadding(bool forAuthKeyInner) {
Expects(_data != nullptr);
Expects(_data->size() > kMessageBodyPosition);
const auto requestSize = (tl::count_length(*this) >> 2);
const auto padding = CountPaddingPrimesCount(
requestSize,
forAuthKeyInner);
const auto fullSize = kMessageBodyPosition + requestSize + padding;
if (uint32(_data->size()) != fullSize) {
_data->resize(fullSize);
if (padding > 0) {
bytes::set_random(bytes::make_span(*_data).subspan(
(fullSize - padding) * sizeof(mtpPrime)));
}
}
}
uint32 SerializedRequest::messageSize() const {
Expects(_data != nullptr);
Expects(_data->size() > kMessageBodyPosition);
const auto ints = (tl::count_length(*this) >> 2);
return kMessageIdInts + kSeqNoInts + kMessageLengthInts + ints;
}
bool SerializedRequest::needAck() const {
Expects(_data != nullptr);
Expects(_data->size() > kMessageBodyPosition);
const auto type = mtpTypeId((*_data)[kMessageBodyPosition]);
switch (type) {
case mtpc_msg_container:
case mtpc_msgs_ack:
case mtpc_http_wait:
case mtpc_bad_msg_notification:
case mtpc_msgs_all_info:
case mtpc_msgs_state_info:
case mtpc_msg_detailed_info:
case mtpc_msg_new_detailed_info:
return false;
}
return true;
}
size_t SerializedRequest::sizeInBytes() const {
Expects(!_data || _data->size() > kMessageBodyPosition);
return _data ? (*_data)[kMessageLengthPosition] : 0;
}
const void *SerializedRequest::dataInBytes() const {
Expects(!_data || _data->size() > kMessageBodyPosition);
return _data ? (_data->constData() + kMessageBodyPosition) : nullptr;
}
} // namespace MTP