transmission/libtransmission/net.cc

883 lines
23 KiB
C++

// This file Copyright © 2010-2022 Transmission authors and contributors.
// It may be used under the MIT (SPDX: MIT) license.
// License text can be found in the licenses/ folder.
#include <algorithm>
#include <array>
#include <cerrno>
#include <climits>
#include <cstdint>
#include <cstring>
#include <ctime>
#include <iterator> // std::back_inserter
#include <string_view>
#include <utility> // std::pair
#include <sys/types.h>
#ifdef _WIN32
#include <ws2tcpip.h>
#else
#include <netinet/tcp.h> /* TCP_CONGESTION */
#endif
#include <event2/util.h>
#include <fmt/core.h>
#include <libutp/utp.h>
#include "transmission.h"
#include "log.h"
#include "net.h"
#include "peer-socket.h"
#include "session.h"
#include "tr-assert.h"
#include "tr-macros.h"
#include "tr-utp.h"
#include "utils.h"
#include "variant.h"
#ifndef IN_MULTICAST
#define IN_MULTICAST(a) (((a)&0xf0000000) == 0xe0000000)
#endif
std::string tr_net_strerror(int err)
{
#ifdef _WIN32
auto buf = std::array<char, 512>{};
auto const len = FormatMessageA(FORMAT_MESSAGE_FROM_SYSTEM, nullptr, err, 0, std::data(buf), std::size(buf), nullptr);
return std::string{ tr_strvStrip(std::data(buf)) };
#else
return std::string{ tr_strerror(err) };
#endif
}
/*
* Compare two tr_address structures.
* Returns:
* <0 if a < b
* >0 if a > b
* 0 if a == b
*/
int tr_address_compare(tr_address const* a, tr_address const* b) noexcept
{
// IPv6 addresses are always "greater than" IPv4
if (a->type != b->type)
{
return a->isIPv4() ? 1 : -1;
}
return a->isIPv4() ? memcmp(&a->addr.addr4, &b->addr.addr4, sizeof(a->addr.addr4)) :
memcmp(&a->addr.addr6.s6_addr, &b->addr.addr6.s6_addr, sizeof(a->addr.addr6.s6_addr));
}
/***********************************************************************
* TCP sockets
**********************************************************************/
[[nodiscard]] std::optional<tr_tos_t> tr_tos_t::fromString(std::string_view name)
{
auto const needle = tr_strlower(tr_strvStrip(name));
for (auto const& [value, key] : Names)
{
if (needle == key)
{
return tr_tos_t(value);
}
}
if (auto value = tr_parseNum<int>(needle); value)
{
return tr_tos_t(*value);
}
return {};
}
std::string tr_tos_t::toString() const
{
for (auto const& [value, key] : Names)
{
if (value_ == value)
{
return std::string{ key };
}
}
return std::to_string(value_);
}
void tr_netSetTOS([[maybe_unused]] tr_socket_t s, [[maybe_unused]] int tos, tr_address_type type)
{
if (s == TR_BAD_SOCKET)
{
return;
}
if (type == TR_AF_INET)
{
#if defined(IP_TOS) && !defined(_WIN32)
if (setsockopt(s, IPPROTO_IP, IP_TOS, (void const*)&tos, sizeof(tos)) == -1)
{
tr_logAddDebug(fmt::format("Can't set TOS '{}': {}", tos, tr_net_strerror(sockerrno)));
}
#endif
}
else if (type == TR_AF_INET6)
{
#if defined(IPV6_TCLASS) && !defined(_WIN32)
if (setsockopt(s, IPPROTO_IPV6, IPV6_TCLASS, (void const*)&tos, sizeof(tos)) == -1)
{
tr_logAddDebug(fmt::format("Can't set IPv6 QoS '{}': {}", tos, tr_net_strerror(sockerrno)));
}
#endif
}
else
{
/* program should never reach here! */
tr_logAddDebug("Something goes wrong while setting TOS/Traffic-Class");
}
}
void tr_netSetCongestionControl([[maybe_unused]] tr_socket_t s, [[maybe_unused]] char const* algorithm)
{
#ifdef TCP_CONGESTION
if (setsockopt(s, IPPROTO_TCP, TCP_CONGESTION, (void const*)algorithm, strlen(algorithm) + 1) == -1)
{
tr_logAddDebug(fmt::format("Can't set congestion control algorithm '{}': {}", algorithm, tr_net_strerror(sockerrno)));
}
#endif
}
std::optional<std::pair<tr_address, tr_port>> tr_address::fromSockaddr(struct sockaddr const* from)
{
if (from == nullptr)
{
return {};
}
if (from->sa_family == AF_INET)
{
auto const* const sin = reinterpret_cast<struct sockaddr_in const*>(from);
auto addr = tr_address{};
addr.type = TR_AF_INET;
addr.addr.addr4 = sin->sin_addr;
return std::make_pair(addr, tr_port::fromNetwork(sin->sin_port));
}
if (from->sa_family == AF_INET6)
{
auto const* const sin6 = reinterpret_cast<struct sockaddr_in6 const*>(from);
auto addr = tr_address{};
addr.type = TR_AF_INET6;
addr.addr.addr6 = sin6->sin6_addr;
return std::make_pair(addr, tr_port::fromNetwork(sin6->sin6_port));
}
return {};
}
std::pair<sockaddr_storage, socklen_t> tr_address::toSockaddr(tr_port port) const noexcept
{
auto ss = sockaddr_storage{};
if (isIPv4())
{
auto* const ss4 = reinterpret_cast<sockaddr_in*>(&ss);
ss4->sin_addr = addr.addr4;
ss4->sin_family = AF_INET;
ss4->sin_port = port.network();
return { ss, sizeof(sockaddr_in) };
}
auto* const ss6 = reinterpret_cast<sockaddr_in6*>(&ss);
ss6->sin6_addr = addr.addr6;
ss6->sin6_family = AF_INET6;
ss6->sin6_flowinfo = 0;
ss6->sin6_port = port.network();
return { ss, sizeof(sockaddr_in6) };
}
static tr_socket_t createSocket(tr_session* session, int domain, int type)
{
TR_ASSERT(session != nullptr);
auto const sockfd = socket(domain, type, 0);
if (sockfd == TR_BAD_SOCKET)
{
if (sockerrno != EAFNOSUPPORT)
{
tr_logAddWarn(fmt::format(
_("Couldn't create socket: {error} ({error_code})"),
fmt::arg("error", tr_net_strerror(sockerrno)),
fmt::arg("error_code", sockerrno)));
}
return TR_BAD_SOCKET;
}
if ((evutil_make_socket_nonblocking(sockfd) == -1) || !session->incPeerCount())
{
tr_netClose(session, sockfd);
return TR_BAD_SOCKET;
}
if (static bool buf_logged = false; !buf_logged)
{
int i = 0;
socklen_t size = sizeof(i);
if (getsockopt(sockfd, SOL_SOCKET, SO_SNDBUF, reinterpret_cast<char*>(&i), &size) != -1)
{
tr_logAddTrace(fmt::format("SO_SNDBUF size is {}", i));
}
i = 0;
size = sizeof(i);
if (getsockopt(sockfd, SOL_SOCKET, SO_RCVBUF, reinterpret_cast<char*>(&i), &size) != -1)
{
tr_logAddTrace(fmt::format("SO_RCVBUF size is {}", i));
}
buf_logged = true;
}
return sockfd;
}
struct tr_peer_socket tr_netOpenPeerSocket(tr_session* session, tr_address const* addr, tr_port port, bool client_is_seed)
{
TR_ASSERT(tr_address_is_valid(addr));
if (!session->allowsTCP())
{
return {};
}
if (!tr_address_is_valid_for_peers(addr, port))
{
return {};
}
static auto constexpr Domains = std::array<int, NUM_TR_AF_INET_TYPES>{ AF_INET, AF_INET6 };
auto const s = createSocket(session, Domains[addr->type], SOCK_STREAM);
if (s == TR_BAD_SOCKET)
{
return {};
}
// seeds don't need a big read buffer, so make it smaller
if (client_is_seed)
{
int n = 8192;
if (setsockopt(s, SOL_SOCKET, SO_RCVBUF, reinterpret_cast<char const*>(&n), sizeof(n)) == -1)
{
tr_logAddDebug(fmt::format("Unable to set SO_RCVBUF on socket {}: {}", s, tr_net_strerror(sockerrno)));
}
}
auto const [sock, addrlen] = addr->toSockaddr(port);
// set source address
auto const [source_addr, is_default_addr] = session->publicAddress(addr->type);
auto const [source_sock, sourcelen] = source_addr.toSockaddr({});
if (bind(s, reinterpret_cast<sockaddr const*>(&source_sock), sourcelen) == -1)
{
tr_logAddWarn(fmt::format(
_("Couldn't set source address {address} on {socket}: {error} ({error_code})"),
fmt::arg("address", source_addr.readable()),
fmt::arg("socket", s),
fmt::arg("error", tr_net_strerror(sockerrno)),
fmt::arg("error_code", sockerrno)));
tr_netClose(session, s);
return {};
}
auto ret = tr_peer_socket{};
if (connect(s, reinterpret_cast<sockaddr const*>(&sock), addrlen) == -1 &&
#ifdef _WIN32
sockerrno != WSAEWOULDBLOCK &&
#endif
sockerrno != EINPROGRESS)
{
if (auto const tmperrno = sockerrno; (tmperrno != ENETUNREACH && tmperrno != EHOSTUNREACH) || addr->isIPv4())
{
tr_logAddWarn(fmt::format(
_("Couldn't connect socket {socket} to {address}:{port}: {error} ({error_code})"),
fmt::arg("socket", s),
fmt::arg("address", addr->readable()),
fmt::arg("port", port.host()),
fmt::arg("error", tr_net_strerror(tmperrno)),
fmt::arg("error_code", tmperrno)));
}
tr_netClose(session, s);
}
else
{
ret = tr_peer_socket_tcp_create(s);
}
tr_logAddTrace(fmt::format("New OUTGOING connection {} ({})", s, addr->readable(port)));
return ret;
}
struct tr_peer_socket tr_netOpenPeerUTPSocket(
tr_session* session,
tr_address const* addr,
tr_port port,
bool /*client_is_seed*/)
{
auto ret = tr_peer_socket{};
if (session->utp_context != nullptr && tr_address_is_valid_for_peers(addr, port))
{
auto const [ss, sslen] = addr->toSockaddr(port);
auto* const socket = utp_create_socket(session->utp_context);
if (socket != nullptr)
{
if (utp_connect(socket, reinterpret_cast<sockaddr const*>(&ss), sslen) != -1)
{
ret = tr_peer_socket_utp_create(socket);
}
else
{
utp_close(socket);
}
}
}
return ret;
}
void tr_netClosePeerSocket(tr_session* session, tr_peer_socket socket)
{
switch (socket.type)
{
case TR_PEER_SOCKET_TYPE_NONE:
break;
case TR_PEER_SOCKET_TYPE_TCP:
tr_netClose(session, socket.handle.tcp);
break;
#ifdef WITH_UTP
case TR_PEER_SOCKET_TYPE_UTP:
utp_set_userdata(socket.handle.utp, nullptr);
utp_close(socket.handle.utp);
break;
#endif
default:
TR_ASSERT_MSG(false, fmt::format(FMT_STRING("unsupported peer socket type {:d}"), socket.type));
}
}
static tr_socket_t tr_netBindTCPImpl(tr_address const& addr, tr_port port, bool suppress_msgs, int* err_out)
{
TR_ASSERT(tr_address_is_valid(&addr));
static auto constexpr Domains = std::array<int, NUM_TR_AF_INET_TYPES>{ AF_INET, AF_INET6 };
auto const fd = socket(Domains[addr.type], SOCK_STREAM, 0);
if (fd == TR_BAD_SOCKET)
{
*err_out = sockerrno;
return TR_BAD_SOCKET;
}
if (evutil_make_socket_nonblocking(fd) == -1)
{
*err_out = sockerrno;
tr_netCloseSocket(fd);
return TR_BAD_SOCKET;
}
int optval = 1;
(void)setsockopt(fd, SOL_SOCKET, SO_KEEPALIVE, reinterpret_cast<char const*>(&optval), sizeof(optval));
(void)setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, reinterpret_cast<char const*>(&optval), sizeof(optval));
#ifdef IPV6_V6ONLY
if (addr.isIPv6() &&
(setsockopt(fd, IPPROTO_IPV6, IPV6_V6ONLY, reinterpret_cast<char const*>(&optval), sizeof(optval)) == -1) &&
(sockerrno != ENOPROTOOPT)) // if the kernel doesn't support it, ignore it
{
*err_out = sockerrno;
tr_netCloseSocket(fd);
return TR_BAD_SOCKET;
}
#endif
auto const [sock, addrlen] = addr.toSockaddr(port);
if (bind(fd, (struct sockaddr*)&sock, addrlen) == -1)
{
int const err = sockerrno;
if (!suppress_msgs)
{
tr_logAddError(fmt::format(
err == EADDRINUSE ?
_("Couldn't bind port {port} on {address}: {error} ({error_code}) -- Is another copy of Transmission already running?") :
_("Couldn't bind port {port} on {address}: {error} ({error_code})"),
fmt::arg("address", addr.readable()),
fmt::arg("port", port.host()),
fmt::arg("error", tr_net_strerror(err)),
fmt::arg("error_code", err)));
}
tr_netCloseSocket(fd);
*err_out = err;
return TR_BAD_SOCKET;
}
if (!suppress_msgs)
{
tr_logAddDebug(fmt::format(FMT_STRING("Bound socket {:d} to port {:d} on {:s}"), fd, port.host(), addr.readable()));
}
#ifdef TCP_FASTOPEN
#ifndef SOL_TCP
#define SOL_TCP IPPROTO_TCP
#endif
optval = 5;
(void)setsockopt(fd, SOL_TCP, TCP_FASTOPEN, reinterpret_cast<char const*>(&optval), sizeof(optval));
#endif
#ifdef _WIN32
if (listen(fd, SOMAXCONN) == -1)
#else /* _WIN32 */
/* Listen queue backlog will be capped to the operating system's limit. */
if (listen(fd, INT_MAX) == -1)
#endif /* _WIN32 */
{
*err_out = sockerrno;
tr_netCloseSocket(fd);
return TR_BAD_SOCKET;
}
return fd;
}
tr_socket_t tr_netBindTCP(tr_address const& addr, tr_port port, bool suppress_msgs)
{
int unused = 0;
return tr_netBindTCPImpl(addr, port, suppress_msgs, &unused);
}
bool tr_net_hasIPv6(tr_port port)
{
static bool result = false;
static bool already_done = false;
if (!already_done)
{
int err = 0;
auto const fd = tr_netBindTCPImpl(tr_address::AnyIPv4(), port, true, &err);
if (fd != TR_BAD_SOCKET || err != EAFNOSUPPORT) /* we support ipv6 */
{
result = true;
}
if (fd != TR_BAD_SOCKET)
{
tr_netCloseSocket(fd);
}
already_done = true;
}
return result;
}
std::optional<std::tuple<tr_address, tr_port, tr_socket_t>> tr_netAccept(tr_session* session, tr_socket_t listening_sockfd)
{
TR_ASSERT(session != nullptr);
// accept the incoming connection
auto sock = sockaddr_storage{};
socklen_t len = sizeof(struct sockaddr_storage);
auto const sockfd = accept(listening_sockfd, (struct sockaddr*)&sock, &len);
if (sockfd == TR_BAD_SOCKET)
{
return {};
}
// get the address and port,
// make the socket unblocking,
// and confirm we don't have too many peers
auto const addrport = tr_address::fromSockaddr(reinterpret_cast<struct sockaddr*>(&sock));
if (!addrport || evutil_make_socket_nonblocking(sockfd) == -1 || !session->incPeerCount())
{
tr_netCloseSocket(sockfd);
return {};
}
return std::make_tuple(addrport->first, addrport->second, sockfd);
}
void tr_netCloseSocket(tr_socket_t sockfd)
{
evutil_closesocket(sockfd);
}
void tr_netClose(tr_session* session, tr_socket_t sockfd)
{
tr_netCloseSocket(sockfd);
session->decPeerCount();
}
/*
get_source_address() and global_unicast_address() were written by
Juliusz Chroboczek, and are covered under the same license as dht.c.
Please feel free to copy them into your software if it can help
unbreaking the double-stack Internet. */
/* Get the source address used for a given destination address. Since
there is no official interface to get this information, we create
a connected UDP socket (connected UDP... hmm...) and check its source
address. */
static int get_source_address(struct sockaddr const* dst, socklen_t dst_len, struct sockaddr* src, socklen_t* src_len)
{
tr_socket_t const s = socket(dst->sa_family, SOCK_DGRAM, 0);
if (s == TR_BAD_SOCKET)
{
return -1;
}
// since it's a UDP socket, this doesn't actually send any packets
if (connect(s, dst, dst_len) == 0 && getsockname(s, src, src_len) == 0)
{
evutil_closesocket(s);
return 0;
}
auto const save = errno;
evutil_closesocket(s);
errno = save;
return -1;
}
/* We all hate NATs. */
static int global_unicast_address(struct sockaddr_storage* ss)
{
if (ss->ss_family == AF_INET)
{
unsigned char const* a = (unsigned char*)&((struct sockaddr_in*)ss)->sin_addr;
if (a[0] == 0 || a[0] == 127 || a[0] >= 224 || a[0] == 10 || (a[0] == 172 && a[1] >= 16 && a[1] <= 31) ||
(a[0] == 192 && a[1] == 168))
{
return 0;
}
return 1;
}
if (ss->ss_family == AF_INET6)
{
unsigned char const* a = (unsigned char*)&((struct sockaddr_in6*)ss)->sin6_addr;
/* 2000::/3 */
return (a[0] & 0xE0) == 0x20 ? 1 : 0;
}
errno = EAFNOSUPPORT;
return -1;
}
static int tr_globalAddress(int af, void* addr, int* addr_len)
{
auto ss = sockaddr_storage{};
socklen_t sslen = sizeof(ss);
auto sin = sockaddr_in{};
auto sin6 = sockaddr_in6{};
struct sockaddr const* sa = nullptr;
socklen_t salen = 0;
switch (af)
{
case AF_INET:
memset(&sin, 0, sizeof(sin));
sin.sin_family = AF_INET;
evutil_inet_pton(AF_INET, "91.121.74.28", &sin.sin_addr);
sin.sin_port = htons(6969);
sa = (struct sockaddr const*)&sin;
salen = sizeof(sin);
break;
case AF_INET6:
memset(&sin6, 0, sizeof(sin6));
sin6.sin6_family = AF_INET6;
/* In order for address selection to work right, this should be
a native IPv6 address, not Teredo or 6to4. */
evutil_inet_pton(AF_INET6, "2001:1890:1112:1::20", &sin6.sin6_addr);
sin6.sin6_port = htons(6969);
sa = (struct sockaddr const*)&sin6;
salen = sizeof(sin6);
break;
default:
return -1;
}
if (int const rc = get_source_address(sa, salen, (struct sockaddr*)&ss, &sslen); rc < 0)
{
return -1;
}
if (global_unicast_address(&ss) == 0)
{
return -1;
}
switch (af)
{
case AF_INET:
if (*addr_len < 4)
{
return -1;
}
memcpy(addr, &((struct sockaddr_in*)&ss)->sin_addr, 4);
*addr_len = 4;
return 1;
case AF_INET6:
if (*addr_len < 16)
{
return -1;
}
memcpy(addr, &((struct sockaddr_in6*)&ss)->sin6_addr, 16);
*addr_len = 16;
return 1;
default:
return -1;
}
}
/* Return our global IPv6 address, with caching. */
std::optional<in6_addr> tr_globalIPv6(tr_session const* session)
{
static auto ipv6 = in6_addr{};
static time_t last_time = 0;
static bool have_ipv6 = false;
/* Re-check every half hour */
if (auto const now = tr_time(); last_time < now - 1800)
{
int addrlen = sizeof(ipv6);
int const rc = tr_globalAddress(AF_INET6, &ipv6, &addrlen);
have_ipv6 = rc >= 0 && addrlen == sizeof(ipv6);
last_time = now;
}
if (!have_ipv6)
{
return {}; // no IPv6 address at all
}
// Return the default address.
// This is useful for checking for connectivity in general.
if (session == nullptr)
{
return ipv6;
}
// We have some sort of address.
// Now make sure that we return our bound address if non-default.
auto const [ipv6_bindaddr, is_default] = session->publicAddress(TR_AF_INET6);
if (!is_default)
{
// return this explicitly-bound address
ipv6 = ipv6_bindaddr.addr.addr6;
}
return ipv6;
}
/***
****
****
***/
static bool isIPv4MappedAddress(tr_address const* addr)
{
return addr->isIPv6() && IN6_IS_ADDR_V4MAPPED(&addr->addr.addr6);
}
static bool isIPv6LinkLocalAddress(tr_address const* addr)
{
return addr->isIPv6() && IN6_IS_ADDR_LINKLOCAL(&addr->addr.addr6);
}
/* isMartianAddr was written by Juliusz Chroboczek,
and is covered under the same license as third-party/dht/dht.c. */
static bool isMartianAddr(struct tr_address const* a)
{
TR_ASSERT(tr_address_is_valid(a));
static auto constexpr Zeroes = std::array<unsigned char, 16>{};
switch (a->type)
{
case TR_AF_INET:
{
auto const* const address = (unsigned char const*)&a->addr.addr4;
return address[0] == 0 || address[0] == 127 || (address[0] & 0xE0) == 0xE0;
}
case TR_AF_INET6:
{
auto const* const address = (unsigned char const*)&a->addr.addr6;
return address[0] == 0xFF ||
(memcmp(address, std::data(Zeroes), 15) == 0 && (address[15] == 0 || address[15] == 1));
}
default:
return true;
}
}
bool tr_address_is_valid_for_peers(tr_address const* addr, tr_port port)
{
return !std::empty(port) && tr_address_is_valid(addr) && !isIPv6LinkLocalAddress(addr) && !isIPv4MappedAddress(addr) &&
!isMartianAddr(addr);
}
struct tr_peer_socket tr_peer_socket_tcp_create(tr_socket_t const handle)
{
TR_ASSERT(handle != TR_BAD_SOCKET);
return { TR_PEER_SOCKET_TYPE_TCP, { handle } };
}
struct tr_peer_socket tr_peer_socket_utp_create(struct UTPSocket* const handle)
{
TR_ASSERT(handle != nullptr);
auto ret = tr_peer_socket{ TR_PEER_SOCKET_TYPE_UTP, {} };
ret.handle.utp = handle;
return ret;
}
/// tr_port
std::pair<tr_port, std::byte const*> tr_port::fromCompact(std::byte const* compact) noexcept
{
static auto constexpr PortLen = size_t{ 2 };
static_assert(PortLen == sizeof(uint16_t));
auto nport = uint16_t{};
std::copy_n(compact, PortLen, reinterpret_cast<std::byte*>(&nport));
compact += PortLen;
return std::make_pair(tr_port::fromNetwork(nport), compact);
}
/// tr_address
std::optional<tr_address> tr_address::fromString(std::string_view address_sv)
{
auto const address_sz = tr_strbuf<char, TR_ADDRSTRLEN>{ address_sv };
auto addr = tr_address{};
if (evutil_inet_pton(AF_INET, address_sz, &addr.addr) == 1)
{
addr.type = TR_AF_INET;
return addr;
}
if (evutil_inet_pton(AF_INET6, address_sz, &addr.addr) == 1)
{
addr.type = TR_AF_INET6;
return addr;
}
return {};
}
std::string_view tr_address::readable(char* out, size_t outlen, tr_port port) const
{
if (std::empty(port))
{
return isIPv4() ? evutil_inet_ntop(AF_INET, &addr, out, outlen) : evutil_inet_ntop(AF_INET6, &addr, out, outlen);
}
auto buf = std::array<char, INET6_ADDRSTRLEN>{};
auto const addr_sv = readable(std::data(buf), std::size(buf));
auto const [end, size] = fmt::format_to_n(out, outlen - 1, FMT_STRING("[{:s}]:{:d}"), addr_sv, port.host());
return { out, size };
}
template<typename OutputIt>
OutputIt tr_address::readable(OutputIt out, tr_port port) const
{
auto addrbuf = std::array<char, TR_ADDRSTRLEN + 16>{};
auto const addr_sv = readable(std::data(addrbuf), std::size(addrbuf), port);
return std::copy(std::begin(addr_sv), std::end(addr_sv), out);
}
template char* tr_address::readable<char*>(char*, tr_port) const;
[[nodiscard]] std::string tr_address::readable(tr_port port) const
{
auto buf = std::string{};
buf.reserve(INET6_ADDRSTRLEN + 16);
this->readable(std::back_inserter(buf), port);
return buf;
}
std::pair<tr_address, std::byte const*> tr_address::fromCompact4(std::byte const* compact) noexcept
{
static auto constexpr Addr4Len = size_t{ 4 };
auto address = tr_address{};
static_assert(sizeof(address.addr.addr4) == Addr4Len);
address.type = TR_AF_INET;
std::copy_n(compact, Addr4Len, reinterpret_cast<std::byte*>(&address.addr));
compact += Addr4Len;
return std::make_pair(address, compact);
}
std::pair<tr_address, std::byte const*> tr_address::fromCompact6(std::byte const* compact) noexcept
{
static auto constexpr Addr6Len = size_t{ 16 };
auto address = tr_address{};
address.type = TR_AF_INET6;
std::copy_n(compact, Addr6Len, reinterpret_cast<std::byte*>(&address.addr.addr6.s6_addr));
compact += Addr6Len;
return std::make_pair(address, compact);
}
int tr_address::compare(tr_address const& that) const noexcept // <=>
{
return tr_address_compare(this, &that);
}