transmission/libtransmission/peer-io.h

353 lines
8.5 KiB
C++

// This file Copyright © 2007-2022 Mnemosyne LLC.
// It may be used under GPLv2 (SPDX: GPL-2.0-only), GPLv3 (SPDX: GPL-3.0-only),
// or any future license endorsed by Mnemosyne LLC.
// License text can be found in the licenses/ folder.
#pragma once
#ifndef __TRANSMISSION__
#error only libtransmission should #include this header.
#endif
/**
***
**/
#include <cstddef> // size_t
#include <cstdint> // uintX_t
#include <ctime>
#include <deque>
#include <memory>
#include <optional>
#include <string>
#include <utility> // std::make_pair
#include "transmission.h"
#include "bandwidth.h"
#include "net.h" // tr_address
#include "peer-mse.h"
#include "peer-socket.h"
#include "tr-assert.h"
#include "tr-buffer.h"
#include "utils-ev.h"
class tr_peerIo;
struct tr_bandwidth;
struct struct_utp_context;
/**
* @addtogroup networked_io Networked IO
* @{
*/
enum ReadState
{
READ_NOW,
READ_LATER,
READ_ERR
};
auto inline constexpr PEER_IO_MAGIC_NUMBER = 206745;
namespace libtransmission::test
{
class HandshakeTest;
} // namespace libtransmission::test
class tr_peerIo final : public std::enable_shared_from_this<tr_peerIo>
{
using DH = tr_message_stream_encryption::DH;
using Filter = tr_message_stream_encryption::Filter;
public:
~tr_peerIo();
// TODO: 8 constructor args is too many; maybe a builder object?
static std::shared_ptr<tr_peerIo> newOutgoing(
tr_session* session,
tr_bandwidth* parent,
struct tr_address const* addr,
tr_port port,
time_t current_time,
tr_sha1_digest_t const& torrent_hash,
bool is_seed,
bool utp);
static std::shared_ptr<tr_peerIo> newIncoming(
tr_session* session,
tr_bandwidth* parent,
struct tr_address const* addr,
tr_port port,
time_t current_time,
struct tr_peer_socket const socket);
void clear();
void readBytes(void* bytes, size_t byte_count);
void readUint8(uint8_t* setme)
{
readBytes(setme, sizeof(uint8_t));
}
void readUint16(uint16_t* setme);
void readUint32(uint32_t* setme);
int reconnect();
void setEnabled(tr_direction dir, bool is_enabled);
[[nodiscard]] constexpr tr_address const& address() const noexcept
{
return addr_;
}
[[nodiscard]] constexpr std::pair<tr_address, tr_port> socketAddress() const noexcept
{
return std::make_pair(addr_, port_);
}
std::string addrStr() const;
void readBufferDrain(size_t byte_count);
[[nodiscard]] auto readBufferSize() const noexcept
{
return std::size(inbuf);
}
template<typename T>
[[nodiscard]] auto readBufferStartsWith(T const& t) const noexcept
{
return inbuf.startsWith(t);
}
void readBufferAdd(void const* data, size_t n_bytes);
size_t flushOutgoingProtocolMsgs(tr_error** error = nullptr);
size_t flush(tr_direction dir, size_t byte_limit, tr_error** error = nullptr);
void writeBytes(void const* bytes, size_t n_bytes, bool is_piece_data);
// Write all the data from `buf`.
// This is a destructive add: `buf` is empty after this call.
void write(libtransmission::Buffer& buf, bool is_piece_data);
[[nodiscard]] size_t getWriteBufferSpace(uint64_t now) const noexcept;
[[nodiscard]] auto hasBandwidthLeft(tr_direction dir) noexcept
{
return bandwidth_.clamp(dir, 1024) > 0;
}
[[nodiscard]] auto getPieceSpeedBytesPerSecond(uint64_t now, tr_direction dir) noexcept
{
return bandwidth_.getPieceSpeedBytesPerSecond(now, dir);
}
constexpr void enableFEXT(bool flag) noexcept
{
fast_extension_supported_ = flag;
}
[[nodiscard]] constexpr auto supportsFEXT() const noexcept
{
return fast_extension_supported_;
}
constexpr void enableLTEP(bool flag) noexcept
{
extended_protocol_supported_ = flag;
}
[[nodiscard]] constexpr auto supportsLTEP() const noexcept
{
return extended_protocol_supported_;
}
constexpr void enableDHT(bool flag) noexcept
{
dht_supported_ = flag;
}
[[nodiscard]] constexpr auto supportsDHT() const noexcept
{
return dht_supported_;
}
[[nodiscard]] constexpr auto supportsUTP() const noexcept
{
return utp_supported_;
}
[[nodiscard]] constexpr auto isSeed() const noexcept
{
return is_seed_;
}
[[nodiscard]] constexpr auto const& bandwidth() const noexcept
{
return bandwidth_;
}
[[nodiscard]] constexpr auto& bandwidth() noexcept
{
return bandwidth_;
}
void setParent(tr_bandwidth* parent)
{
bandwidth_.setParent(parent);
}
[[nodiscard]] constexpr auto isIncoming() const noexcept
{
return is_incoming_;
}
void setTorrentHash(tr_sha1_digest_t hash) noexcept
{
torrent_hash_ = hash;
}
[[nodiscard]] constexpr auto const& torrentHash() const noexcept
{
return torrent_hash_;
}
using tr_can_read_cb = ReadState (*)(tr_peerIo* io, void* user_data, size_t* setme_piece_byte_count);
using tr_did_write_cb = void (*)(tr_peerIo* io, size_t bytesWritten, bool wasPieceData, void* userData);
using tr_net_error_cb = void (*)(tr_peerIo* io, short what, void* userData);
void setCallbacks(tr_can_read_cb readcb, tr_did_write_cb writecb, tr_net_error_cb errcb, void* user_data);
void clearCallbacks()
{
setCallbacks(nullptr, nullptr, nullptr, nullptr);
}
struct tr_peer_socket socket = {};
tr_session* const session;
time_t const time_created;
tr_can_read_cb canRead = nullptr;
tr_did_write_cb didWrite = nullptr;
tr_net_error_cb gotError = nullptr;
void* userData = nullptr;
libtransmission::Buffer inbuf;
libtransmission::Buffer outbuf;
std::deque<std::pair<size_t /*n_bytes*/, bool /*is_piece_data*/>> outbuf_info;
libtransmission::evhelpers::event_unique_ptr event_read;
libtransmission::evhelpers::event_unique_ptr event_write;
short int pendingEvents = 0;
tr_priority_t priority = TR_PRI_NORMAL;
bool utp_supported_ = false;
void decryptInit(bool is_incoming, DH const& dh, tr_sha1_digest_t const& info_hash)
{
filter().decryptInit(is_incoming, dh, info_hash);
}
void decrypt(size_t buflen, void* buf)
{
filter().decrypt(buflen, buf);
}
void encryptInit(bool is_incoming, DH const& dh, tr_sha1_digest_t const& info_hash)
{
filter().encryptInit(is_incoming, dh, info_hash);
}
void encrypt(size_t buflen, void* buf)
{
filter().encrypt(buflen, buf);
}
[[nodiscard]] bool isEncrypted() const noexcept
{
return filter_.get() != nullptr;
}
static void utpInit(struct_utp_context* ctx);
private:
friend class libtransmission::test::HandshakeTest;
// this is only public for testing purposes.
// production code should use newOutgoing() or newIncoming()
static std::shared_ptr<tr_peerIo> create(
tr_session* session,
tr_bandwidth* parent,
tr_address const* addr,
tr_port port,
time_t current_time,
tr_sha1_digest_t const* torrent_hash,
bool is_incoming,
bool is_seed,
struct tr_peer_socket const socket);
tr_peerIo(
tr_session* session_in,
tr_sha1_digest_t const* torrent_hash,
bool is_incoming,
tr_address const& addr,
tr_port port,
bool is_seed,
time_t current_time,
tr_bandwidth* parent_bandwidth)
: session{ session_in }
, time_created{ current_time }
, bandwidth_{ parent_bandwidth }
, addr_{ addr }
, port_{ port }
, is_seed_{ is_seed }
, is_incoming_{ is_incoming }
{
if (torrent_hash != nullptr)
{
torrent_hash_ = *torrent_hash;
}
}
Filter& filter()
{
if (!filter_)
{
filter_ = std::make_unique<Filter>();
}
return *filter_;
}
tr_bandwidth bandwidth_;
std::unique_ptr<tr_message_stream_encryption::Filter> filter_;
std::optional<tr_sha1_digest_t> torrent_hash_;
tr_address const addr_;
tr_port const port_;
bool const is_seed_;
bool const is_incoming_;
bool dht_supported_ = false;
bool extended_protocol_supported_ = false;
bool fast_extension_supported_ = false;
};
constexpr bool tr_isPeerIo(tr_peerIo const* io)
{
return io != nullptr && tr_address_is_valid(&io->address());
}