mirror of
https://github.com/dolphin-emu/dolphin.git
synced 2026-10-19 17:18:59 +02:00
Acts1631
93097f65ea
Pending traversal packets were only expired after receive events. If a client did not acknowledge a response and no more packets arrived, the server retained the pending entry indefinitely. Update the current time before handling socket timeouts. Pending packets will then retry and expire while the server is idle.
527 lines
13 KiB
C++
527 lines
13 KiB
C++
// SPDX-License-Identifier: CC0-1.0
|
|
|
|
// The central server implementation.
|
|
#include <arpa/inet.h>
|
|
#include <cerrno>
|
|
#include <chrono>
|
|
#include <cstdio>
|
|
#include <cstdlib>
|
|
#include <cstring>
|
|
#include <netinet/in.h>
|
|
#include <sys/select.h>
|
|
#include <sys/socket.h>
|
|
#include <tuple>
|
|
#include <unordered_map>
|
|
#include <vector>
|
|
|
|
#include <fmt/format.h>
|
|
|
|
#ifdef HAVE_LIBSYSTEMD
|
|
#include <systemd/sd-daemon.h>
|
|
#endif
|
|
|
|
#include "Common/Random.h"
|
|
#include "Common/TraversalProto.h"
|
|
|
|
#define DEBUG 0
|
|
#define NUMBER_OF_TRIES 5
|
|
#define PORT 6262
|
|
#define PORT_ALT 6226
|
|
|
|
static u64 currentTime;
|
|
|
|
struct OutgoingPacketInfo
|
|
{
|
|
Common::TraversalPacket packet;
|
|
Common::TraversalRequestId misc;
|
|
bool fromAlt;
|
|
sockaddr_in6 dest;
|
|
int tries;
|
|
u64 sendTime;
|
|
};
|
|
|
|
template <typename T>
|
|
struct EvictEntry
|
|
{
|
|
u64 updateTime;
|
|
T value;
|
|
};
|
|
|
|
template <typename V>
|
|
struct EvictFindResult
|
|
{
|
|
bool found;
|
|
V* value;
|
|
};
|
|
|
|
template <typename K, typename V>
|
|
EvictFindResult<V> EvictFind(std::unordered_map<K, EvictEntry<V>>& map, const K& key,
|
|
bool refresh = false)
|
|
{
|
|
retry:
|
|
const u64 expiryTime = 30 * 1000000; // 30s
|
|
EvictFindResult<V> result;
|
|
if (map.bucket_count())
|
|
{
|
|
auto bucket = map.bucket(key);
|
|
auto it = map.begin(bucket);
|
|
for (; it != map.end(bucket); ++it)
|
|
{
|
|
if (currentTime - it->second.updateTime > expiryTime)
|
|
{
|
|
map.erase(it->first);
|
|
goto retry;
|
|
}
|
|
if (it->first == key)
|
|
{
|
|
if (refresh)
|
|
it->second.updateTime = currentTime;
|
|
result.found = true;
|
|
result.value = &it->second.value;
|
|
return result;
|
|
}
|
|
}
|
|
}
|
|
#if DEBUG
|
|
fmt::print("failed to find key '");
|
|
for (size_t i = 0; i < sizeof(key); i++)
|
|
{
|
|
fmt::print("{:02x}", ((u8*)&key)[i]);
|
|
}
|
|
fmt::print("'\n");
|
|
#endif
|
|
result.found = false;
|
|
return result;
|
|
}
|
|
|
|
template <typename K, typename V>
|
|
V* EvictSet(std::unordered_map<K, EvictEntry<V>>& map, const K& key)
|
|
{
|
|
// can't use a local_iterator to emplace...
|
|
auto& result = map[key];
|
|
result.updateTime = currentTime;
|
|
return &result.value;
|
|
}
|
|
|
|
namespace std
|
|
{
|
|
template <>
|
|
struct hash<Common::TraversalHostId>
|
|
{
|
|
size_t operator()(const Common::TraversalHostId& id) const noexcept
|
|
{
|
|
auto p = (u32*)id.data();
|
|
return p[0] ^ ((p[1] << 13) | (p[1] >> 19));
|
|
}
|
|
};
|
|
} // namespace std
|
|
|
|
using ConnectedClients =
|
|
std::unordered_map<Common::TraversalHostId, EvictEntry<Common::TraversalInetAddress>>;
|
|
using OutgoingPackets = std::unordered_map<Common::TraversalRequestId, OutgoingPacketInfo>;
|
|
|
|
static int sock;
|
|
static int sockAlt;
|
|
static OutgoingPackets outgoingPackets;
|
|
static ConnectedClients connectedClients;
|
|
|
|
static Common::TraversalInetAddress MakeInetAddress(const sockaddr_in6& addr)
|
|
{
|
|
if (addr.sin6_family != AF_INET6)
|
|
{
|
|
fmt::print(stderr, "bad sockaddr_in6\n");
|
|
exit(1);
|
|
}
|
|
u32* words = (u32*)addr.sin6_addr.s6_addr;
|
|
Common::TraversalInetAddress result = {};
|
|
if (words[0] == 0 && words[1] == 0 && words[2] == 0xffff0000)
|
|
{
|
|
result.isIPV6 = false;
|
|
result.address[0] = words[3];
|
|
}
|
|
else
|
|
{
|
|
result.isIPV6 = true;
|
|
memcpy(result.address, words, sizeof(result.address));
|
|
}
|
|
result.port = addr.sin6_port;
|
|
return result;
|
|
}
|
|
|
|
static sockaddr_in6 MakeSinAddr(const Common::TraversalInetAddress& addr)
|
|
{
|
|
sockaddr_in6 result;
|
|
#ifdef SIN6_LEN
|
|
result.sin6_len = sizeof(result);
|
|
#endif
|
|
result.sin6_family = AF_INET6;
|
|
result.sin6_port = addr.port;
|
|
result.sin6_flowinfo = 0;
|
|
if (addr.isIPV6)
|
|
{
|
|
memcpy(&result.sin6_addr, addr.address, 16);
|
|
}
|
|
else
|
|
{
|
|
u32* words = (u32*)result.sin6_addr.s6_addr;
|
|
words[0] = 0;
|
|
words[1] = 0;
|
|
words[2] = 0xffff0000;
|
|
words[3] = addr.address[0];
|
|
}
|
|
result.sin6_scope_id = 0;
|
|
return result;
|
|
}
|
|
|
|
static void GetRandomHostId(Common::TraversalHostId* hostId)
|
|
{
|
|
char buf[9]{};
|
|
const u32 num = Common::Random::GenerateValue<u32>();
|
|
fmt::format_to_n(buf, sizeof(buf) - 1, "{:08x}", num);
|
|
memcpy(hostId->data(), buf, 8);
|
|
}
|
|
|
|
static const char* SenderName(sockaddr_in6* addr)
|
|
{
|
|
static char buf[INET6_ADDRSTRLEN + 10]{};
|
|
inet_ntop(PF_INET6, &addr->sin6_addr, buf, sizeof(buf));
|
|
fmt::format_to(buf + strlen(buf), ":{}", ntohs(addr->sin6_port));
|
|
return buf;
|
|
}
|
|
|
|
static void TrySend(const void* buffer, size_t size, sockaddr_in6* addr, bool fromAlt)
|
|
{
|
|
#if DEBUG
|
|
const auto* packet = static_cast<const Common::TraversalPacket*>(buffer);
|
|
fmt::print("{}-> {} {} {}\n", fromAlt ? "alt " : "", static_cast<int>(packet->type),
|
|
static_cast<long long>(packet->requestId), SenderName(addr));
|
|
#endif
|
|
if ((size_t)sendto(fromAlt ? sockAlt : sock, buffer, size, 0, (sockaddr*)addr, sizeof(*addr)) !=
|
|
size)
|
|
{
|
|
perror("sendto");
|
|
}
|
|
}
|
|
|
|
static Common::TraversalPacket* AllocPacket(const sockaddr_in6& dest, bool fromAlt,
|
|
Common::TraversalRequestId misc = 0)
|
|
{
|
|
Common::TraversalRequestId requestId{};
|
|
Common::Random::Generate(&requestId, sizeof(requestId));
|
|
OutgoingPacketInfo* info = &outgoingPackets[requestId];
|
|
info->fromAlt = fromAlt;
|
|
info->dest = dest;
|
|
info->misc = misc;
|
|
info->tries = 0;
|
|
info->sendTime = currentTime;
|
|
Common::TraversalPacket* result = &info->packet;
|
|
memset(result, 0, sizeof(*result));
|
|
result->requestId = requestId;
|
|
return result;
|
|
}
|
|
|
|
static void SendPacket(OutgoingPacketInfo* info)
|
|
{
|
|
info->tries++;
|
|
info->sendTime = currentTime;
|
|
TrySend(&info->packet, sizeof(info->packet), &info->dest, info->fromAlt);
|
|
}
|
|
|
|
static void ResendPackets()
|
|
{
|
|
std::vector<std::tuple<Common::TraversalInetAddress, bool, Common::TraversalRequestId>>
|
|
todoFailures;
|
|
todoFailures.clear();
|
|
for (auto it = outgoingPackets.begin(); it != outgoingPackets.end();)
|
|
{
|
|
OutgoingPacketInfo* info = &it->second;
|
|
if (currentTime - info->sendTime >= (u64)(300000 * info->tries))
|
|
{
|
|
if (info->tries >= NUMBER_OF_TRIES)
|
|
{
|
|
if (info->packet.type == Common::TraversalPacketType::PleaseSendPacket)
|
|
{
|
|
todoFailures.push_back(
|
|
std::make_tuple(info->packet.pleaseSendPacket.address, info->fromAlt, info->misc));
|
|
}
|
|
it = outgoingPackets.erase(it);
|
|
continue;
|
|
}
|
|
else
|
|
{
|
|
SendPacket(info);
|
|
}
|
|
}
|
|
++it;
|
|
}
|
|
|
|
for (const auto& p : todoFailures)
|
|
{
|
|
Common::TraversalPacket* fail = AllocPacket(MakeSinAddr(std::get<0>(p)), std::get<1>(p));
|
|
fail->type = Common::TraversalPacketType::ConnectFailed;
|
|
fail->connectFailed.requestId = std::get<2>(p);
|
|
fail->connectFailed.reason = Common::TraversalConnectFailedReason::ClientDidntRespond;
|
|
}
|
|
}
|
|
|
|
static void HandlePacket(Common::TraversalPacket* packet, sockaddr_in6* addr, bool toAlt)
|
|
{
|
|
#if DEBUG
|
|
fmt::print("<- {} {} {}\n", static_cast<int>(packet->type),
|
|
static_cast<long long>(packet->requestId), SenderName(addr));
|
|
#endif
|
|
bool packetOk = true;
|
|
switch (packet->type)
|
|
{
|
|
case Common::TraversalPacketType::Ack:
|
|
{
|
|
auto it = outgoingPackets.find(packet->requestId);
|
|
if (it == outgoingPackets.end())
|
|
break;
|
|
|
|
OutgoingPacketInfo* info = &it->second;
|
|
|
|
if (info->packet.type == Common::TraversalPacketType::PleaseSendPacket)
|
|
{
|
|
auto* ready = AllocPacket(MakeSinAddr(info->packet.pleaseSendPacket.address), toAlt);
|
|
if (packet->ack.ok)
|
|
{
|
|
ready->type = Common::TraversalPacketType::ConnectReady;
|
|
ready->connectReady.requestId = info->misc;
|
|
ready->connectReady.address = MakeInetAddress(info->dest);
|
|
}
|
|
else
|
|
{
|
|
ready->type = Common::TraversalPacketType::ConnectFailed;
|
|
ready->connectFailed.requestId = info->misc;
|
|
ready->connectFailed.reason = Common::TraversalConnectFailedReason::ClientFailure;
|
|
}
|
|
}
|
|
|
|
outgoingPackets.erase(it);
|
|
break;
|
|
}
|
|
case Common::TraversalPacketType::Ping:
|
|
{
|
|
auto r = EvictFind(connectedClients, packet->ping.hostId, true);
|
|
packetOk = r.found;
|
|
break;
|
|
}
|
|
case Common::TraversalPacketType::HelloFromClient:
|
|
{
|
|
u8 ok = packet->helloFromClient.protoVersion <= Common::TraversalProtoVersion;
|
|
Common::TraversalPacket* reply = AllocPacket(*addr, toAlt);
|
|
reply->type = Common::TraversalPacketType::HelloFromServer;
|
|
reply->helloFromServer.ok = ok;
|
|
if (ok)
|
|
{
|
|
Common::TraversalHostId hostId{};
|
|
Common::TraversalInetAddress* iaddr{};
|
|
// not that there is any significant change of
|
|
// duplication, but...
|
|
while (true)
|
|
{
|
|
GetRandomHostId(&hostId);
|
|
auto r = EvictFind(connectedClients, hostId);
|
|
if (!r.found)
|
|
{
|
|
iaddr = EvictSet(connectedClients, hostId);
|
|
break;
|
|
}
|
|
}
|
|
|
|
*iaddr = MakeInetAddress(*addr);
|
|
|
|
reply->helloFromServer.yourAddress = *iaddr;
|
|
reply->helloFromServer.yourHostId = hostId;
|
|
}
|
|
break;
|
|
}
|
|
case Common::TraversalPacketType::ConnectPlease:
|
|
{
|
|
Common::TraversalHostId& hostId = packet->connectPlease.hostId;
|
|
auto r = EvictFind(connectedClients, hostId);
|
|
if (!r.found)
|
|
{
|
|
Common::TraversalPacket* reply = AllocPacket(*addr, toAlt);
|
|
reply->type = Common::TraversalPacketType::ConnectFailed;
|
|
reply->connectFailed.requestId = packet->requestId;
|
|
reply->connectFailed.reason = Common::TraversalConnectFailedReason::NoSuchClient;
|
|
}
|
|
else
|
|
{
|
|
Common::TraversalPacket* please =
|
|
AllocPacket(MakeSinAddr(*r.value), toAlt, packet->requestId);
|
|
please->type = Common::TraversalPacketType::PleaseSendPacket;
|
|
please->pleaseSendPacket.address = MakeInetAddress(*addr);
|
|
}
|
|
break;
|
|
}
|
|
case Common::TraversalPacketType::TestPlease:
|
|
{
|
|
Common::TraversalHostId& hostId = packet->testPlease.hostId;
|
|
auto r = EvictFind(connectedClients, hostId);
|
|
if (r.found)
|
|
{
|
|
Common::TraversalPacket ack = {};
|
|
ack.type = Common::TraversalPacketType::Ack;
|
|
ack.requestId = packet->requestId;
|
|
ack.ack.ok = true;
|
|
sockaddr_in6 mainAddr = MakeSinAddr(*r.value);
|
|
TrySend(&ack, sizeof(ack), &mainAddr, toAlt);
|
|
}
|
|
break;
|
|
}
|
|
default:
|
|
fmt::print(stderr, "received unknown packet type {} from {}\n", static_cast<int>(packet->type),
|
|
SenderName(addr));
|
|
break;
|
|
}
|
|
if (packet->type != Common::TraversalPacketType::Ack)
|
|
{
|
|
Common::TraversalPacket ack = {};
|
|
ack.type = Common::TraversalPacketType::Ack;
|
|
ack.requestId = packet->requestId;
|
|
ack.ack.ok = packetOk;
|
|
TrySend(&ack, sizeof(ack), addr,
|
|
packet->type != Common::TraversalPacketType::TestPlease ? toAlt : !toAlt);
|
|
}
|
|
}
|
|
|
|
int main()
|
|
{
|
|
int rv;
|
|
sock = socket(PF_INET6, SOCK_DGRAM, 0);
|
|
if (sock == -1)
|
|
{
|
|
perror("socket");
|
|
return 1;
|
|
}
|
|
sockAlt = socket(PF_INET6, SOCK_DGRAM, 0);
|
|
if (sockAlt == -1)
|
|
{
|
|
perror("socket alt");
|
|
return 1;
|
|
}
|
|
int no = 0;
|
|
rv = setsockopt(sock, IPPROTO_IPV6, IPV6_V6ONLY, &no, sizeof(no));
|
|
if (rv < 0)
|
|
{
|
|
perror("setsockopt IPV6_V6ONLY");
|
|
return 1;
|
|
}
|
|
rv = setsockopt(sockAlt, IPPROTO_IPV6, IPV6_V6ONLY, &no, sizeof(no));
|
|
if (rv < 0)
|
|
{
|
|
perror("setsockopt IPV6_V6ONLY alt");
|
|
return 1;
|
|
}
|
|
in6_addr any = IN6ADDR_ANY_INIT;
|
|
sockaddr_in6 addr;
|
|
#ifdef SIN6_LEN
|
|
addr.sin6_len = sizeof(addr);
|
|
#endif
|
|
addr.sin6_family = AF_INET6;
|
|
addr.sin6_port = htons(PORT);
|
|
addr.sin6_flowinfo = 0;
|
|
addr.sin6_addr = any;
|
|
addr.sin6_scope_id = 0;
|
|
|
|
rv = bind(sock, (sockaddr*)&addr, sizeof(addr));
|
|
if (rv < 0)
|
|
{
|
|
perror("bind");
|
|
return 1;
|
|
}
|
|
addr.sin6_port = htons(PORT_ALT);
|
|
rv = bind(sockAlt, (sockaddr*)&addr, sizeof(addr));
|
|
if (rv < 0)
|
|
{
|
|
perror("bind alt");
|
|
return 1;
|
|
}
|
|
|
|
timeval tv;
|
|
tv.tv_sec = 0;
|
|
tv.tv_usec = 300000;
|
|
rv = setsockopt(sock, SOL_SOCKET, SO_RCVTIMEO, &tv, sizeof(tv));
|
|
if (rv < 0)
|
|
{
|
|
perror("setsockopt SO_RCVTIMEO");
|
|
return 1;
|
|
}
|
|
rv = setsockopt(sockAlt, SOL_SOCKET, SO_RCVTIMEO, &tv, sizeof(tv));
|
|
if (rv < 0)
|
|
{
|
|
perror("setsockopt SO_RCVTIMEO alt");
|
|
return 1;
|
|
}
|
|
|
|
#ifdef HAVE_LIBSYSTEMD
|
|
sd_notifyf(0, "READY=1\nSTATUS=Listening on port %d (alt port: %d)", PORT, PORT_ALT);
|
|
#endif
|
|
|
|
while (true)
|
|
{
|
|
tv.tv_sec = 0;
|
|
tv.tv_usec = 300000;
|
|
fd_set readSet;
|
|
FD_ZERO(&readSet);
|
|
FD_SET(sock, &readSet);
|
|
FD_SET(sockAlt, &readSet);
|
|
rv = select(std::max(sock, sockAlt) + 1, &readSet, nullptr, nullptr, &tv);
|
|
currentTime = std::chrono::duration_cast<std::chrono::microseconds>(
|
|
std::chrono::steady_clock::now().time_since_epoch())
|
|
.count();
|
|
if (rv < 0)
|
|
{
|
|
if (errno != EINTR && errno != EAGAIN)
|
|
{
|
|
perror("recvfrom");
|
|
return 1;
|
|
}
|
|
}
|
|
|
|
int recvsock;
|
|
if (FD_ISSET(sock, &readSet))
|
|
{
|
|
recvsock = sock;
|
|
}
|
|
else if (FD_ISSET(sockAlt, &readSet))
|
|
{
|
|
recvsock = sockAlt;
|
|
}
|
|
else
|
|
{
|
|
ResendPackets();
|
|
continue;
|
|
}
|
|
sockaddr_in6 raddr;
|
|
socklen_t addrLen = sizeof(raddr);
|
|
Common::TraversalPacket packet{};
|
|
// note: switch to recvmmsg (yes, mmsg) if this becomes
|
|
// expensive
|
|
rv = recvfrom(recvsock, &packet, sizeof(packet), 0, (sockaddr*)&raddr, &addrLen);
|
|
if (rv < 0)
|
|
{
|
|
if (errno != EINTR && errno != EAGAIN)
|
|
{
|
|
perror("recvfrom");
|
|
return 1;
|
|
}
|
|
}
|
|
else if ((size_t)rv < sizeof(packet))
|
|
{
|
|
fmt::print(stderr, "received short packet from {}\n", SenderName(&raddr));
|
|
}
|
|
else
|
|
{
|
|
HandlePacket(&packet, &raddr, recvsock == sockAlt);
|
|
}
|
|
ResendPackets();
|
|
#ifdef HAVE_LIBSYSTEMD
|
|
sd_notify(0, "WATCHDOG=1");
|
|
#endif
|
|
}
|
|
}
|