tdlight/td/mtproto/DhHandshake.h
2022-01-01 03:35:39 +03:00

125 lines
3.0 KiB
C++

//
// Copyright Aliaksei Levin (levlam@telegram.org), Arseny Smirnov (arseny30@gmail.com) 2014-2022
//
// Distributed under the Boost Software License, Version 1.0. (See accompanying
// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
//
#pragma once
#include "td/utils/BigNum.h"
#include "td/utils/common.h"
#include "td/utils/Slice.h"
#include "td/utils/Status.h"
#include <utility>
namespace td {
namespace mtproto {
class DhCallback;
class DhHandshake {
public:
void set_config(int32 g_int, Slice prime_str);
static Status check_config(int32 g_int, Slice prime_str, DhCallback *callback);
bool has_config() const {
return has_config_;
}
void set_g_a_hash(Slice g_a_hash);
void set_g_a(Slice g_a_str);
bool has_g_a() const {
return has_g_a_;
}
string get_g_a() const;
string get_g_b() const;
string get_g_b_hash() const;
Status run_checks(bool skip_config_check, DhCallback *callback) TD_WARN_UNUSED_RESULT;
BigNum get_g() const;
BigNum get_p() const;
BigNum get_b() const;
BigNum get_g_ab();
std::pair<int64, string> gen_key();
static int64 calc_key_id(Slice auth_key);
enum Flags { HasConfig = 1, HasGA = 2 };
template <class StorerT>
void store(StorerT &storer) const {
auto flags = 0;
if (has_config_) {
flags |= HasConfig;
}
if (has_g_a_) {
flags |= HasGA;
}
storer.store_int(flags);
if (has_config_) {
// prime_, prime_str_, b_, g_, g_int_, g_b_
storer.store_string(prime_str_);
storer.store_string(b_.to_binary());
storer.store_int(g_int_);
storer.store_string(g_b_.to_binary());
}
if (has_g_a_) {
storer.store_string(g_a_.to_binary());
}
}
template <class ParserT>
void parse(ParserT &parser) {
auto flags = parser.fetch_int();
if (flags & HasConfig) {
has_config_ = true;
}
if (flags & HasGA) {
has_g_a_ = true;
}
if (has_config_) {
// prime_, prime_str_, b_, g_, g_int_, g_b_
prime_str_ = parser.template fetch_string<std::string>();
prime_ = BigNum::from_binary(prime_str_);
b_ = BigNum::from_binary(parser.template fetch_string<string>());
g_int_ = parser.fetch_int();
g_.set_value(g_int_);
g_b_ = BigNum::from_binary(parser.template fetch_string<string>());
}
if (has_g_a_) {
g_a_ = BigNum::from_binary(parser.template fetch_string<string>());
}
}
private:
static Status check_config(Slice prime_str, const BigNum &prime, int32 g_int, BigNumContext &ctx,
DhCallback *callback) TD_WARN_UNUSED_RESULT;
static Status dh_check(const BigNum &prime, const BigNum &g_a, const BigNum &g_b) TD_WARN_UNUSED_RESULT;
string prime_str_;
BigNum prime_;
BigNum g_;
int32 g_int_ = 0;
BigNum b_;
BigNum g_b_;
BigNum g_a_;
string g_a_hash_;
bool has_g_a_hash_{false};
bool ok_g_a_hash_{false};
bool has_config_ = false;
bool has_g_a_ = false;
BigNumContext ctx_;
};
} // namespace mtproto
} // namespace td