791 lines
		
	
	
	
		
			20 KiB
		
	
	
	
		
			C++
		
	
	
	
	
	
			
		
		
	
	
			791 lines
		
	
	
	
		
			20 KiB
		
	
	
	
		
			C++
		
	
	
	
	
	
/*
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This file is part of Telegram Desktop,
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the official desktop application for the Telegram messaging service.
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For license and copyright information please follow this link:
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https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL
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*/
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#include "mtproto/details/mtproto_tls_socket.h"
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#include "mtproto/details/mtproto_tcp_socket.h"
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#include "base/openssl_help.h"
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#include "base/bytes.h"
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#include "base/invoke_queued.h"
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#include "base/unixtime.h"
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#include "base/qt/qt_common_adapters.h"
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#include <QtCore/QtEndian>
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#include <range/v3/algorithm/reverse.hpp>
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namespace MTP::details {
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namespace {
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constexpr auto kMaxGrease = 8;
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constexpr auto kClientHelloLength = 517;
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constexpr auto kHelloDigestLength = 32;
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constexpr auto kLengthSize = sizeof(uint16);
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const auto kServerHelloPart1 = qstr("\x16\x03\x03");
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const auto kServerHelloPart3 = qstr("\x14\x03\x03\x00\x01\x01\x17\x03\x03");
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constexpr auto kServerHelloDigestPosition = 11;
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const auto kServerHeader = qstr("\x17\x03\x03");
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constexpr auto kClientPartSize = 2878;
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const auto kClientPrefix = qstr("\x14\x03\x03\x00\x01\x01");
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const auto kClientHeader = qstr("\x17\x03\x03");
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using BigNum = openssl::BigNum;
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using BigNumContext = openssl::Context;
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[[nodiscard]] MTPTlsClientHello PrepareClientHelloRules() {
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	auto stack = std::vector<QVector<MTPTlsBlock>>();
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	const auto pushToBack = [&](MTPTlsBlock &&block) {
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		Expects(!stack.empty());
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		stack.back().push_back(std::move(block));
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	};
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	const auto S = [&](QLatin1String s) {
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		const auto data = QByteArray(s.data(), s.size());
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		pushToBack(MTP_tlsBlockString(MTP_bytes(data)));
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	};
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	const auto Z = [&](int length) {
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		pushToBack(MTP_tlsBlockZero(MTP_int(length)));
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	};
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	const auto G = [&](int seed) {
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		pushToBack(MTP_tlsBlockGrease(MTP_int(seed)));
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	};
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	const auto R = [&](int length) {
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		pushToBack(MTP_tlsBlockRandom(MTP_int(length)));
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	};
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	const auto D = [&] {
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		pushToBack(MTP_tlsBlockDomain());
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	};
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	const auto K = [&] {
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		pushToBack(MTP_tlsBlockPublicKey());
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	};
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	const auto Open = [&] {
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		stack.emplace_back();
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	};
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	const auto Close = [&] {
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		Expects(stack.size() > 1);
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		const auto blocks = std::move(stack.back());
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		stack.pop_back();
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		pushToBack(MTP_tlsBlockScope(MTP_vector<MTPTlsBlock>(blocks)));
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	};
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	const auto Finish = [&] {
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		Expects(stack.size() == 1);
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		return stack.back();
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	};
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	stack.emplace_back();
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	S(qstr("\x16\x03\x01\x02\x00\x01\x00\x01\xfc\x03\x03"));
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	Z(32);
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	S(qstr("\x20"));
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	R(32);
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	S(qstr("\x00\x20"));
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	G(0);
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	S(qstr(""
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		"\x13\x01\x13\x02\x13\x03\xc0\x2b\xc0\x2f\xc0\x2c\xc0\x30\xcc\xa9"
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		"\xcc\xa8\xc0\x13\xc0\x14\x00\x9c\x00\x9d\x00\x2f\x00\x35\x01\x00"
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		"\x01\x93"));
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	G(2);
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	S(qstr("\x00\x00\x00\x00"));
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	Open();
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	Open();
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	S(qstr("\x00"));
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	Open();
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	D();
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	Close();
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	Close();
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	Close();
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	S(qstr("\x00\x17\x00\x00\xff\x01\x00\x01\x00\x00\x0a\x00\x0a\x00\x08"));
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	G(4);
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	S(qstr(""
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		"\x00\x1d\x00\x17\x00\x18\x00\x0b\x00\x02\x01\x00\x00\x23\x00\x00"
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		"\x00\x10\x00\x0e\x00\x0c\x02\x68\x32\x08\x68\x74\x74\x70\x2f\x31"
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		"\x2e\x31\x00\x05\x00\x05\x01\x00\x00\x00\x00\x00\x0d\x00\x12\x00"
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		"\x10\x04\x03\x08\x04\x04\x01\x05\x03\x08\x05\x05\x01\x08\x06\x06"
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		"\x01\x00\x12\x00\x00\x00\x33\x00\x2b\x00\x29"));
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	G(4);
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	S(qstr("\x00\x01\x00\x00\x1d\x00\x20"));
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	K();
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	S(qstr("\x00\x2d\x00\x02\x01\x01\x00\x2b\x00\x0b\x0a"));
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	G(6);
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	S(qstr("\x03\x04\x03\x03\x03\x02\x03\x01\x00\x1b\x00\x03\x02\x00\x02"));
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	G(3);
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	S(qstr("\x00\x01\x00\x00\x15"));
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	return MTP_tlsClientHello(MTP_vector<MTPTlsBlock>(Finish()));
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}
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[[nodiscard]] bytes::vector PrepareGreases() {
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	auto result = bytes::vector(kMaxGrease);
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	bytes::set_random(result);
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	for (auto &byte : result) {
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		byte = bytes::type((uchar(byte) & 0xF0) + 0x0A);
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	}
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	static_assert(kMaxGrease % 2 == 0);
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	for (auto i = 0; i != kMaxGrease; i += 2) {
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		if (result[i] == result[i + 1]) {
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			result[i + 1] = bytes::type(uchar(result[i + 1]) ^ 0x10);
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		}
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	}
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	return result;
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}
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// Returns y^2 = x^3 + 486662 * x^2 + x.
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[[nodiscard]] BigNum GenerateY2(
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		const BigNum &x,
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		const BigNum &mod,
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		const BigNumContext &context) {
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	auto coef = BigNum(486662);
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	auto y = BigNum::ModAdd(x, coef, mod, context);
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	y.setModMul(y, x, mod, context);
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	coef.setWord(1);
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	y.setModAdd(y, coef, mod, context);
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	return BigNum::ModMul(y, x, mod, context);
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}
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// Returns x_2 = (x^2 - 1)^2/(4*y^2).
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[[nodiscard]] BigNum GenerateX2(
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		const BigNum &x,
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		const BigNum &mod,
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		const BigNumContext &context) {
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	auto denominator = GenerateY2(x, mod, context);
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	auto coef = BigNum(4);
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	denominator.setModMul(denominator, coef, mod, context);
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	auto numerator = BigNum::ModMul(x, x, mod, context);
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	coef.setWord(1);
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	numerator.setModSub(numerator, coef, mod, context);
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	numerator.setModMul(numerator, numerator, mod, context);
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	denominator.setModInverse(denominator, mod, context);
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	return BigNum::ModMul(numerator, denominator, mod, context);
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}
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[[nodiscard]] bytes::vector GeneratePublicKey() {
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	const auto context = BigNumContext();
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	const char modBytes[] = ""
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		"\x7f\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff"
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		"\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xed";
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	const char powBytes[] = ""
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		"\x3f\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff"
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		"\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xf6";
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	const auto mod = BigNum(bytes::make_span(modBytes).subspan(0, 32));
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	const auto pow = BigNum(bytes::make_span(powBytes).subspan(0, 32));
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	auto x = BigNum();
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	do {
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		while (true) {
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			auto random = bytes::vector(32);
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			bytes::set_random(random);
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			random[31] &= bytes::type(0x7FU);
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			x.setBytes(random);
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			x.setModMul(x, x, mod, context);
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			auto y = GenerateY2(x, mod, context);
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			if (BigNum::ModExp(y, pow, mod, context).isOne()) {
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				break;
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			}
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		}
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		for (auto i = 0; i != 3; ++i) {
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			x = GenerateX2(x, mod, context);
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		}
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		const auto xBytes = x.getBytes();
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		Assert(!xBytes.empty());
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		Assert(xBytes.size() <= 32);
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	} while (x.bytesSize() == 32);
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	const auto xBytes = x.getBytes();
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	auto result = bytes::vector(32, bytes::type());
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	bytes::copy(
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		bytes::make_span(result).subspan(32 - xBytes.size()),
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		xBytes);
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	ranges::reverse(result);
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	//auto string = QString();
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	//string.reserve(64);
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	//for (const auto byte : result) {
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	//	const auto code = uchar(byte);
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	//	const auto hex = [](uchar value) -> char {
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	//		if (value >= 0 && value <= 9) {
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	//			return '0' + value;
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	//		} else if (value >= 10 && value <= 15) {
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	//			return 'a' + (value - 10);
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	//		}
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	//		return '-';
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	//	};
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	//	string.append(hex(code / 16)).append(hex(code % 16));
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	//}
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	//LOG(("KEY: %1").arg(string));
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	return result;
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}
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struct ClientHello {
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	QByteArray data;
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	QByteArray digest;
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};
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class ClientHelloGenerator {
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public:
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	ClientHelloGenerator(
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		const MTPTlsClientHello &rules,
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		bytes::const_span domain,
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		bytes::const_span key);
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	[[nodiscard]] ClientHello result();
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private:
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	[[nodiscard]] bytes::span grow(int size);
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	void writeBlocks(const QVector<MTPTlsBlock> &blocks);
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	void writeBlock(const MTPTlsBlock &data);
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	void writeBlock(const MTPDtlsBlockString &data);
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	void writeBlock(const MTPDtlsBlockZero &data);
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	void writeBlock(const MTPDtlsBlockGrease &data);
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	void writeBlock(const MTPDtlsBlockRandom &data);
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	void writeBlock(const MTPDtlsBlockDomain &data);
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	void writeBlock(const MTPDtlsBlockPublicKey &data);
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	void writeBlock(const MTPDtlsBlockScope &data);
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	void writePadding();
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	void writeDigest();
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	void writeTimestamp();
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	bytes::const_span _domain;
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	bytes::const_span _key;
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	bytes::vector _greases;
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	std::vector<int> _scopeStack;
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	QByteArray _result;
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	QByteArray _digest;
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	int _digestPosition = -1;
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	bool _error = false;
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};
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ClientHelloGenerator::ClientHelloGenerator(
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	const MTPTlsClientHello &rules,
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	bytes::const_span domain,
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	bytes::const_span key)
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: _domain(domain)
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, _key(key)
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, _greases(PrepareGreases()) {
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	_result.reserve(kClientHelloLength);
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	writeBlocks(rules.match([&](const MTPDtlsClientHello &data) {
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		return data.vblocks().v;
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	}));
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	writePadding();
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	writeDigest();
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	writeTimestamp();
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}
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ClientHello ClientHelloGenerator::result() {
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	return {
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		_error ? QByteArray() : std::move(_result),
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		_error ? QByteArray() : std::move(_digest) };
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}
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bytes::span ClientHelloGenerator::grow(int size) {
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	if (_error
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		|| size <= 0
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		|| _result.size() + size > kClientHelloLength) {
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		_error = true;
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		return bytes::span();
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	}
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	const auto offset = _result.size();
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	_result.resize(offset + size);
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	return bytes::make_detached_span(_result).subspan(offset);
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}
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void ClientHelloGenerator::writeBlocks(const QVector<MTPTlsBlock> &blocks) {
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	for (const auto &block : blocks) {
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		writeBlock(block);
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	}
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}
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void ClientHelloGenerator::writeBlock(const MTPTlsBlock &data) {
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	data.match([&](const auto &data) {
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		writeBlock(data);
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	});
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}
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void ClientHelloGenerator::writeBlock(const MTPDtlsBlockString &data) {
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	const auto &bytes = data.vdata().v;
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	const auto storage = grow(bytes.size());
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	if (storage.empty()) {
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		return;
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	}
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	bytes::copy(storage, bytes::make_span(bytes));
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}
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void ClientHelloGenerator::writeBlock(const MTPDtlsBlockZero &data) {
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	const auto length = data.vlength().v;
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	const auto already = _result.size();
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	const auto storage = grow(length);
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	if (storage.empty()) {
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		return;
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	}
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	if (length == kHelloDigestLength && _digestPosition < 0) {
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		_digestPosition = already;
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	}
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	bytes::set_with_const(storage, bytes::type(0));
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}
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void ClientHelloGenerator::writeBlock(const MTPDtlsBlockGrease &data) {
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	const auto seed = data.vseed().v;
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	if (seed < 0 || seed >= _greases.size()) {
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		_error = true;
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		return;
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	}
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	const auto storage = grow(2);
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	if (storage.empty()) {
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		return;
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	}
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	bytes::set_with_const(storage, _greases[seed]);
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}
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void ClientHelloGenerator::writeBlock(const MTPDtlsBlockRandom &data) {
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	const auto length = data.vlength().v;
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	const auto storage = grow(length);
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	if (storage.empty()) {
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		return;
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	}
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	bytes::set_random(storage);
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}
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void ClientHelloGenerator::writeBlock(const MTPDtlsBlockDomain &data) {
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	const auto storage = grow(_domain.size());
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	if (storage.empty()) {
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		return;
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	}
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	bytes::copy(storage, _domain);
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}
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void ClientHelloGenerator::writeBlock(const MTPDtlsBlockPublicKey &data) {
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	const auto key = GeneratePublicKey();
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	const auto storage = grow(key.size());
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	if (storage.empty()) {
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		return;
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	}
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	bytes::copy(storage, key);
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}
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void ClientHelloGenerator::writeBlock(const MTPDtlsBlockScope &data) {
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	const auto storage = grow(kLengthSize);
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	if (storage.empty()) {
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		return;
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	}
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	const auto already = _result.size();
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	writeBlocks(data.ventries().v);
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	const auto length = qToBigEndian(uint16(_result.size() - already));
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	bytes::copy(storage, bytes::object_as_span(&length));
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}
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void ClientHelloGenerator::writePadding() {
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	const auto padding = kClientHelloLength - kLengthSize - _result.size();
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	writeBlock(MTP_tlsBlockScope(
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		MTP_vector<MTPTlsBlock>(1, MTP_tlsBlockZero(MTP_int(padding)))));
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}
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void ClientHelloGenerator::writeDigest() {
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	if (_digestPosition < 0) {
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		_error = true;
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		return;
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	}
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	bytes::copy(
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		bytes::make_detached_span(_result).subspan(_digestPosition),
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		openssl::HmacSha256(_key, bytes::make_span(_result)));
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}
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void ClientHelloGenerator::writeTimestamp() {
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	if (_digestPosition < 0) {
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		_error = true;
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		return;
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	}
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	const auto storage = bytes::make_detached_span(_result).subspan(
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		_digestPosition + kHelloDigestLength - sizeof(int32),
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		sizeof(int32));
 | 
						|
	auto already = int32();
 | 
						|
	bytes::copy(bytes::object_as_span(&already), storage);
 | 
						|
	already ^= qToLittleEndian(int32(base::unixtime::http_now()));
 | 
						|
	bytes::copy(storage, bytes::object_as_span(&already));
 | 
						|
 | 
						|
	_digest = QByteArray(kHelloDigestLength, Qt::Uninitialized);
 | 
						|
	bytes::copy(
 | 
						|
		bytes::make_detached_span(_digest),
 | 
						|
		bytes::make_detached_span(_result).subspan(
 | 
						|
			_digestPosition,
 | 
						|
			kHelloDigestLength));
 | 
						|
}
 | 
						|
 | 
						|
[[nodiscard]] ClientHello PrepareClientHello(
 | 
						|
		const MTPTlsClientHello &rules,
 | 
						|
		bytes::const_span domain,
 | 
						|
		bytes::const_span key) {
 | 
						|
	return ClientHelloGenerator(rules, domain, key).result();
 | 
						|
}
 | 
						|
 | 
						|
[[nodiscard]] bool CheckPart(bytes::const_span data, QLatin1String check) {
 | 
						|
	if (data.size() < check.size()) {
 | 
						|
		return false;
 | 
						|
	}
 | 
						|
	return !bytes::compare(
 | 
						|
		data.subspan(0, check.size()),
 | 
						|
		bytes::make_span(check.data(), check.size()));
 | 
						|
}
 | 
						|
 | 
						|
[[nodiscard]] int ReadPartLength(bytes::const_span data, int offset) {
 | 
						|
	const auto storage = data.subspan(offset, kLengthSize);
 | 
						|
	return qFromBigEndian(
 | 
						|
		*reinterpret_cast<const uint16*>(storage.data()));
 | 
						|
}
 | 
						|
 | 
						|
} // namespace
 | 
						|
 | 
						|
TlsSocket::TlsSocket(
 | 
						|
	not_null<QThread*> thread,
 | 
						|
	const bytes::vector &secret,
 | 
						|
	const QNetworkProxy &proxy,
 | 
						|
	bool protocolForFiles)
 | 
						|
: AbstractSocket(thread)
 | 
						|
, _secret(secret) {
 | 
						|
	Expects(_secret.size() >= 21 && _secret[0] == bytes::type(0xEE));
 | 
						|
 | 
						|
	_socket.moveToThread(thread);
 | 
						|
	_socket.setProxy(proxy);
 | 
						|
	if (protocolForFiles) {
 | 
						|
		_socket.setSocketOption(
 | 
						|
			QAbstractSocket::SendBufferSizeSocketOption,
 | 
						|
			kFilesSendBufferSize);
 | 
						|
		_socket.setSocketOption(
 | 
						|
			QAbstractSocket::ReceiveBufferSizeSocketOption,
 | 
						|
			kFilesReceiveBufferSize);
 | 
						|
	}
 | 
						|
	const auto wrap = [&](auto handler) {
 | 
						|
		return [=](auto &&...args) {
 | 
						|
			InvokeQueued(this, [=] { handler(args...); });
 | 
						|
		};
 | 
						|
	};
 | 
						|
	using Error = QAbstractSocket::SocketError;
 | 
						|
	connect(
 | 
						|
		&_socket,
 | 
						|
		&QTcpSocket::connected,
 | 
						|
		wrap([=] { plainConnected(); }));
 | 
						|
	connect(
 | 
						|
		&_socket,
 | 
						|
		&QTcpSocket::disconnected,
 | 
						|
		wrap([=] { plainDisconnected(); }));
 | 
						|
	connect(
 | 
						|
		&_socket,
 | 
						|
		&QTcpSocket::readyRead,
 | 
						|
		wrap([=] { plainReadyRead(); }));
 | 
						|
	connect(
 | 
						|
		&_socket,
 | 
						|
		base::QTcpSocket_error,
 | 
						|
		wrap([=](Error e) { handleError(e); }));
 | 
						|
}
 | 
						|
 | 
						|
bytes::const_span TlsSocket::domainFromSecret() const {
 | 
						|
	return bytes::make_span(_secret).subspan(17);
 | 
						|
}
 | 
						|
 | 
						|
bytes::const_span TlsSocket::keyFromSecret() const {
 | 
						|
	return bytes::make_span(_secret).subspan(1, 16);
 | 
						|
}
 | 
						|
 | 
						|
void TlsSocket::plainConnected() {
 | 
						|
	if (_state != State::Connecting) {
 | 
						|
		return;
 | 
						|
	}
 | 
						|
 | 
						|
	static const auto kClientHelloRules = PrepareClientHelloRules();
 | 
						|
	const auto hello = PrepareClientHello(
 | 
						|
		kClientHelloRules,
 | 
						|
		domainFromSecret(),
 | 
						|
		keyFromSecret());
 | 
						|
	if (hello.data.isEmpty()) {
 | 
						|
		logError(888, "Could not generate Client Hello.");
 | 
						|
		_state = State::Error;
 | 
						|
		_error.fire({});
 | 
						|
	} else {
 | 
						|
		_state = State::WaitingHello;
 | 
						|
		_incoming = hello.digest;
 | 
						|
		_socket.write(hello.data);
 | 
						|
	}
 | 
						|
}
 | 
						|
 | 
						|
void TlsSocket::plainDisconnected() {
 | 
						|
	_state = State::NotConnected;
 | 
						|
	_incoming = QByteArray();
 | 
						|
	_serverHelloLength = 0;
 | 
						|
	_incomingGoodDataOffset = 0;
 | 
						|
	_incomingGoodDataLimit = 0;
 | 
						|
	_disconnected.fire({});
 | 
						|
}
 | 
						|
 | 
						|
void TlsSocket::plainReadyRead() {
 | 
						|
	switch (_state) {
 | 
						|
	case State::WaitingHello: return readHello();
 | 
						|
	case State::Connected: return readData();
 | 
						|
	}
 | 
						|
}
 | 
						|
 | 
						|
bool TlsSocket::requiredHelloPartReady() const {
 | 
						|
	return _incoming.size() >= kHelloDigestLength + _serverHelloLength;
 | 
						|
}
 | 
						|
 | 
						|
void TlsSocket::readHello() {
 | 
						|
	const auto parts1Size = kServerHelloPart1.size() + kLengthSize;
 | 
						|
	if (!_serverHelloLength) {
 | 
						|
		_serverHelloLength = parts1Size;
 | 
						|
	}
 | 
						|
	while (!requiredHelloPartReady()) {
 | 
						|
		if (!_socket.bytesAvailable()) {
 | 
						|
			return;
 | 
						|
		}
 | 
						|
		_incoming.append(_socket.readAll());
 | 
						|
	}
 | 
						|
	checkHelloParts12(parts1Size);
 | 
						|
}
 | 
						|
 | 
						|
void TlsSocket::checkHelloParts12(int parts1Size) {
 | 
						|
	const auto data = bytes::make_span(_incoming).subspan(
 | 
						|
		kHelloDigestLength,
 | 
						|
		parts1Size);
 | 
						|
	const auto part2Size = ReadPartLength(data, parts1Size - kLengthSize);
 | 
						|
	const auto parts123Size = parts1Size
 | 
						|
		+ part2Size
 | 
						|
		+ kServerHelloPart3.size()
 | 
						|
		+ kLengthSize;
 | 
						|
	if (_serverHelloLength == parts1Size) {
 | 
						|
		const auto part1Offset = parts1Size
 | 
						|
			- kLengthSize
 | 
						|
			- kServerHelloPart1.size();
 | 
						|
		if (!CheckPart(data.subspan(part1Offset), kServerHelloPart1)) {
 | 
						|
			logError(888, "Bad Server Hello part1.");
 | 
						|
			handleError();
 | 
						|
			return;
 | 
						|
		}
 | 
						|
		_serverHelloLength = parts123Size;
 | 
						|
		if (!requiredHelloPartReady()) {
 | 
						|
			readHello();
 | 
						|
			return;
 | 
						|
		}
 | 
						|
	}
 | 
						|
	checkHelloParts34(parts123Size);
 | 
						|
}
 | 
						|
 | 
						|
void TlsSocket::checkHelloParts34(int parts123Size) {
 | 
						|
	const auto data = bytes::make_span(_incoming).subspan(
 | 
						|
		kHelloDigestLength,
 | 
						|
		parts123Size);
 | 
						|
	const auto part4Size = ReadPartLength(data, parts123Size - kLengthSize);
 | 
						|
	const auto full = parts123Size + part4Size;
 | 
						|
	if (_serverHelloLength == parts123Size) {
 | 
						|
		const auto part3Offset = parts123Size
 | 
						|
			- kLengthSize
 | 
						|
			- kServerHelloPart3.size();
 | 
						|
		if (!CheckPart(data.subspan(part3Offset), kServerHelloPart3)) {
 | 
						|
			logError(888, "Bad Server Hello part.");
 | 
						|
			handleError();
 | 
						|
			return;
 | 
						|
		}
 | 
						|
		_serverHelloLength = full;
 | 
						|
		if (!requiredHelloPartReady()) {
 | 
						|
			readHello();
 | 
						|
			return;
 | 
						|
		}
 | 
						|
	}
 | 
						|
	checkHelloDigest();
 | 
						|
}
 | 
						|
 | 
						|
void TlsSocket::checkHelloDigest() {
 | 
						|
	const auto fulldata = bytes::make_detached_span(_incoming).subspan(
 | 
						|
		0,
 | 
						|
		kHelloDigestLength + _serverHelloLength);
 | 
						|
	const auto digest = fulldata.subspan(
 | 
						|
		kHelloDigestLength + kServerHelloDigestPosition,
 | 
						|
		kHelloDigestLength);
 | 
						|
	const auto digestCopy = bytes::make_vector(digest);
 | 
						|
	bytes::set_with_const(digest, bytes::type(0));
 | 
						|
	const auto check = openssl::HmacSha256(keyFromSecret(), fulldata);
 | 
						|
	if (bytes::compare(digestCopy, check) != 0) {
 | 
						|
		logError(888, "Bad Server Hello digest.");
 | 
						|
		handleError();
 | 
						|
		return;
 | 
						|
	}
 | 
						|
	shiftIncomingBy(fulldata.size());
 | 
						|
	if (!_incoming.isEmpty()) {
 | 
						|
		InvokeQueued(this, [=] {
 | 
						|
			if (!checkNextPacket()) {
 | 
						|
				handleError();
 | 
						|
			}
 | 
						|
		});
 | 
						|
	}
 | 
						|
	_incomingGoodDataOffset = _incomingGoodDataLimit = 0;
 | 
						|
	_state = State::Connected;
 | 
						|
	_connected.fire({});
 | 
						|
}
 | 
						|
 | 
						|
void TlsSocket::readData() {
 | 
						|
	if (!isConnected()) {
 | 
						|
		return;
 | 
						|
	}
 | 
						|
	_incoming.append(_socket.readAll());
 | 
						|
	if (!checkNextPacket()) {
 | 
						|
		handleError();
 | 
						|
	} else if (hasBytesAvailable()) {
 | 
						|
		_readyRead.fire({});
 | 
						|
	}
 | 
						|
}
 | 
						|
 | 
						|
bool TlsSocket::checkNextPacket() {
 | 
						|
	auto offset = 0;
 | 
						|
	const auto incoming = bytes::make_span(_incoming);
 | 
						|
	while (!_incomingGoodDataLimit) {
 | 
						|
		const auto fullHeader = kServerHeader.size() + kLengthSize;
 | 
						|
		if (incoming.size() <= offset + fullHeader) {
 | 
						|
			return true;
 | 
						|
		}
 | 
						|
		if (!CheckPart(incoming.subspan(offset), kServerHeader)) {
 | 
						|
			logError(888, "Bad packet header.");
 | 
						|
			return false;
 | 
						|
		}
 | 
						|
		const auto length = ReadPartLength(
 | 
						|
			incoming,
 | 
						|
			offset + kServerHeader.size());
 | 
						|
		if (length > 0) {
 | 
						|
			if (offset > 0) {
 | 
						|
				shiftIncomingBy(offset);
 | 
						|
			}
 | 
						|
			_incomingGoodDataOffset = fullHeader;
 | 
						|
			_incomingGoodDataLimit = length;
 | 
						|
		} else {
 | 
						|
			offset += kServerHeader.size() + kLengthSize + length;
 | 
						|
		}
 | 
						|
	}
 | 
						|
	return true;
 | 
						|
}
 | 
						|
 | 
						|
void TlsSocket::shiftIncomingBy(int amount) {
 | 
						|
	Expects(_incomingGoodDataOffset == 0);
 | 
						|
	Expects(_incomingGoodDataLimit == 0);
 | 
						|
 | 
						|
	const auto incoming = bytes::make_detached_span(_incoming);
 | 
						|
	if (incoming.size() > amount) {
 | 
						|
		bytes::move(incoming, incoming.subspan(amount));
 | 
						|
		_incoming.chop(amount);
 | 
						|
	} else {
 | 
						|
		_incoming.clear();
 | 
						|
	}
 | 
						|
}
 | 
						|
 | 
						|
void TlsSocket::connectToHost(const QString &address, int port) {
 | 
						|
	Expects(_state == State::NotConnected);
 | 
						|
 | 
						|
	_state = State::Connecting;
 | 
						|
	_socket.connectToHost(address, port);
 | 
						|
}
 | 
						|
 | 
						|
bool TlsSocket::isGoodStartNonce(bytes::const_span nonce) {
 | 
						|
	return true;
 | 
						|
}
 | 
						|
 | 
						|
void TlsSocket::timedOut() {
 | 
						|
	_syncTimeRequests.fire({});
 | 
						|
}
 | 
						|
 | 
						|
bool TlsSocket::isConnected() {
 | 
						|
	return (_state == State::Connected);
 | 
						|
}
 | 
						|
 | 
						|
bool TlsSocket::hasBytesAvailable() {
 | 
						|
	return (_incomingGoodDataLimit > 0)
 | 
						|
		&& (_incomingGoodDataOffset < _incoming.size());
 | 
						|
}
 | 
						|
 | 
						|
int64 TlsSocket::read(bytes::span buffer) {
 | 
						|
	auto written = int64(0);
 | 
						|
	while (_incomingGoodDataLimit) {
 | 
						|
		const auto available = std::min(
 | 
						|
			_incomingGoodDataLimit,
 | 
						|
			int(_incoming.size()) - _incomingGoodDataOffset);
 | 
						|
		if (available <= 0) {
 | 
						|
			return written;
 | 
						|
		}
 | 
						|
		const auto write = std::min(std::size_t(available), buffer.size());
 | 
						|
		if (write <= 0) {
 | 
						|
			return written;
 | 
						|
		}
 | 
						|
		bytes::copy(
 | 
						|
			buffer,
 | 
						|
			bytes::make_span(_incoming).subspan(
 | 
						|
				_incomingGoodDataOffset,
 | 
						|
				write));
 | 
						|
		written += write;
 | 
						|
		buffer = buffer.subspan(write);
 | 
						|
		_incomingGoodDataLimit -= write;
 | 
						|
		_incomingGoodDataOffset += write;
 | 
						|
		if (_incomingGoodDataLimit) {
 | 
						|
			return written;
 | 
						|
		}
 | 
						|
		shiftIncomingBy(base::take(_incomingGoodDataOffset));
 | 
						|
		if (!checkNextPacket()) {
 | 
						|
			_state = State::Error;
 | 
						|
			InvokeQueued(this, [=] { handleError(); });
 | 
						|
			return written;
 | 
						|
		}
 | 
						|
	}
 | 
						|
	return written;
 | 
						|
}
 | 
						|
 | 
						|
void TlsSocket::write(bytes::const_span prefix, bytes::const_span buffer) {
 | 
						|
	Expects(!buffer.empty());
 | 
						|
 | 
						|
	if (!isConnected()) {
 | 
						|
		return;
 | 
						|
	}
 | 
						|
	if (!prefix.empty()) {
 | 
						|
		_socket.write(kClientPrefix.data(), kClientPrefix.size());
 | 
						|
	}
 | 
						|
	while (!buffer.empty()) {
 | 
						|
		const auto write = std::min(
 | 
						|
			kClientPartSize - prefix.size(),
 | 
						|
			buffer.size());
 | 
						|
		_socket.write(kClientHeader.data(), kClientHeader.size());
 | 
						|
		const auto size = qToBigEndian(uint16(prefix.size() + write));
 | 
						|
		_socket.write(reinterpret_cast<const char*>(&size), sizeof(size));
 | 
						|
		if (!prefix.empty()) {
 | 
						|
			_socket.write(
 | 
						|
				reinterpret_cast<const char*>(prefix.data()),
 | 
						|
				prefix.size());
 | 
						|
			prefix = bytes::const_span();
 | 
						|
		}
 | 
						|
		_socket.write(
 | 
						|
			reinterpret_cast<const char*>(buffer.data()),
 | 
						|
			write);
 | 
						|
		buffer = buffer.subspan(write);
 | 
						|
	}
 | 
						|
}
 | 
						|
 | 
						|
int32 TlsSocket::debugState() {
 | 
						|
	return _socket.state();
 | 
						|
}
 | 
						|
 | 
						|
QString TlsSocket::debugPostfix() const {
 | 
						|
	return u"_ee"_q;
 | 
						|
}
 | 
						|
 | 
						|
void TlsSocket::handleError(int errorCode) {
 | 
						|
	if (_state != State::Connected) {
 | 
						|
		_syncTimeRequests.fire({});
 | 
						|
	}
 | 
						|
	if (errorCode) {
 | 
						|
		logError(errorCode, _socket.errorString());
 | 
						|
	}
 | 
						|
	_state = State::Error;
 | 
						|
	_error.fire({});
 | 
						|
}
 | 
						|
 | 
						|
} // namespace MTP::details
 |