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#include "network_universe.hh"
#include <cstring>
#include <iostream>
#include "fake_sockets.hh"
namespace tox::test {
std::ostream &operator<<(std::ostream &os, TcpFlags flags)
{
bool first = true;
if (flags.value & 0x02) {
os << (first ? "" : "|") << "SYN";
first = false;
}
if (flags.value & 0x10) {
os << (first ? "" : "|") << "ACK";
first = false;
}
if (flags.value & 0x01) {
os << (first ? "" : "|") << "FIN";
first = false;
}
if (flags.value & 0x04) {
os << (first ? "" : "|") << "RST";
first = false;
}
if (first)
os << "NONE";
return os << "(" << static_cast<int>(flags.value) << ")";
}
bool NetworkUniverse::IP_Port_Key::operator<(const IP_Port_Key &other) const
{
if (port != other.port)
return port < other.port;
if (ip.family.value != other.ip.family.value)
return ip.family.value < other.ip.family.value;
if (net_family_is_ipv4(ip.family)) {
return ip.ip.v4.uint32 < other.ip.ip.v4.uint32;
}
return std::memcmp(&ip.ip.v6, &other.ip.ip.v6, sizeof(ip.ip.v6)) < 0;
}
NetworkUniverse::NetworkUniverse() { }
NetworkUniverse::~NetworkUniverse() { }
bool NetworkUniverse::bind_udp(IP ip, uint16_t port, FakeUdpSocket *_Nonnull socket)
{
std::lock_guard<std::recursive_mutex> lock(mutex_);
IP_Port_Key key{ip, port};
if (udp_bindings_.count(key))
return false;
udp_bindings_[key] = socket;
return true;
}
void NetworkUniverse::unbind_udp(IP ip, uint16_t port)
{
std::lock_guard<std::recursive_mutex> lock(mutex_);
udp_bindings_.erase({ip, port});
}
bool NetworkUniverse::bind_tcp(IP ip, uint16_t port, FakeTcpSocket *_Nonnull socket)
{
std::lock_guard<std::recursive_mutex> lock(mutex_);
tcp_bindings_.insert({{ip, port}, socket});
return true;
}
void NetworkUniverse::unbind_tcp(IP ip, uint16_t port, FakeTcpSocket *_Nonnull socket)
{
std::lock_guard<std::recursive_mutex> lock(mutex_);
auto range = tcp_bindings_.equal_range({ip, port});
for (auto it = range.first; it != range.second; ++it) {
if (it->second == socket) {
tcp_bindings_.erase(it);
break;
}
}
}
void NetworkUniverse::send_packet(Packet p)
{
// Apply filters
for (const auto &filter : filters_) {
if (!filter(p))
return;
}
// Notify observers
for (const auto &observer : observers_) {
observer(p);
}
p.delivery_time += global_latency_ms_;
std::lock_guard<std::recursive_mutex> lock(mutex_);
p.sequence_number = next_packet_id_++;
if (verbose_) {
Ip_Ntoa from_str, to_str;
net_ip_ntoa(&p.from.ip, &from_str);
net_ip_ntoa(&p.to.ip, &to_str);
std::cerr << "[NetworkUniverse] Enqueued packet #" << p.sequence_number << " from "
<< from_str.buf << ":" << net_ntohs(p.from.port) << " to " << to_str.buf << ":"
<< net_ntohs(p.to.port);
if (p.is_tcp) {
std::cerr << " (TCP Flags=" << TcpFlags{p.tcp_flags} << " Seq=" << p.seq
<< " Ack=" << p.ack << ")";
}
std::cerr << " with size " << p.data.size() << std::endl;
}
event_queue_.push(std::move(p));
}
static bool is_ipv4_mapped(const IP &ip)
{
if (!net_family_is_ipv6(ip.family))
return false;
const uint8_t *b = ip.ip.v6.uint8;
for (int i = 0; i < 10; ++i)
if (b[i] != 0)
return false;
if (b[10] != 0xFF || b[11] != 0xFF)
return false;
return true;
}
static IP extract_ipv4(const IP &ip)
{
IP ip4;
ip_init(&ip4, false);
const uint8_t *b = ip.ip.v6.uint8;
std::memcpy(ip4.ip.v4.uint8, b + 12, 4);
return ip4;
}
bool is_loopback(const IP &ip)
{
if (net_family_is_ipv4(ip.family)) {
return ip.ip.v4.uint32 == net_htonl(0x7F000001);
}
if (net_family_is_ipv6(ip.family)) {
const uint8_t *b = ip.ip.v6.uint8;
for (int i = 0; i < 15; ++i) {
if (b[i] != 0) {
return false;
}
}
return b[15] == 1;
}
return false;
}
void NetworkUniverse::process_events(uint64_t current_time_ms)
{
while (true) {
Packet p;
std::vector<FakeTcpSocket *> tcp_targets;
FakeUdpSocket *udp_target = nullptr;
bool has_packet = false;
{
std::lock_guard<std::recursive_mutex> lock(mutex_);
if (!event_queue_.empty()) {
const Packet &top = event_queue_.top();
if (verbose_) {
std::cerr << "[NetworkUniverse] Peek packet: time=" << top.delivery_time
<< " current=" << current_time_ms << " tcp=" << top.is_tcp
<< std::endl;
}
}
if (!event_queue_.empty() && event_queue_.top().delivery_time <= current_time_ms) {
p = event_queue_.top();
event_queue_.pop();
has_packet = true;
if (verbose_) {
Ip_Ntoa from_str, to_str;
net_ip_ntoa(&p.from.ip, &from_str);
net_ip_ntoa(&p.to.ip, &to_str);
std::cerr << "[NetworkUniverse] Processing packet #" << p.sequence_number
<< " from " << from_str.buf << ":" << net_ntohs(p.from.port) << " to "
<< to_str.buf << ":" << net_ntohs(p.to.port)
<< " (TCP=" << (p.is_tcp ? "true" : "false");
if (p.is_tcp) {
std::cerr << " Flags=" << TcpFlags{p.tcp_flags} << " Seq=" << p.seq
<< " Ack=" << p.ack;
}
std::cerr << " Size=" << p.data.size() << ")" << std::endl;
}
IP target_ip = p.to.ip;
if (p.is_tcp) {
if (is_loopback(target_ip)
&& tcp_bindings_.count({target_ip, net_ntohs(p.to.port)}) == 0) {
if (verbose_) {
std::cerr << "[NetworkUniverse] Loopback packet to "
<< static_cast<int>(target_ip.ip.v4.uint8[3])
<< " redirected to "
<< static_cast<int>(p.from.ip.ip.v4.uint8[3]) << std::endl;
}
target_ip = p.from.ip;
}
auto range = tcp_bindings_.equal_range({target_ip, net_ntohs(p.to.port)});
FakeTcpSocket *listen_match = nullptr;
for (auto it = range.first; it != range.second; ++it) {
FakeTcpSocket *s = it->second;
if (s->state() == FakeTcpSocket::LISTEN) {
listen_match = s;
} else {
const IP_Port &remote = s->remote_addr();
if (net_ntohs(p.from.port) == net_ntohs(remote.port)) {
if (ip_equal(&p.from.ip, &remote.ip)
|| (is_loopback(p.from.ip) && ip_equal(&remote.ip, &target_ip))
|| (is_loopback(remote.ip)
&& ip_equal(&p.from.ip, &target_ip))) {
tcp_targets.push_back(s);
}
}
}
}
if (listen_match && (p.tcp_flags & 0x02)) {
tcp_targets.push_back(listen_match);
}
if (verbose_) {
std::cerr << "[NetworkUniverse] Routing TCP to "
<< static_cast<int>(target_ip.ip.v4.uint8[0]) << "."
<< static_cast<int>(target_ip.ip.v4.uint8[3]) << ":"
<< net_ntohs(p.to.port)
<< ". Targets found: " << tcp_targets.size() << std::endl;
}
if (tcp_targets.empty()) {
if (verbose_) {
std::cerr << "[NetworkUniverse] WARNING: No TCP targets for "
<< static_cast<int>(target_ip.ip.v4.uint8[0]) << "."
<< static_cast<int>(target_ip.ip.v4.uint8[3]) << ":"
<< net_ntohs(p.to.port) << std::endl;
}
}
} else {
if (is_loopback(target_ip)
&& udp_bindings_.count({target_ip, net_ntohs(p.to.port)}) == 0) {
target_ip = p.from.ip;
}
if (udp_bindings_.count({target_ip, net_ntohs(p.to.port)})) {
udp_target = udp_bindings_[{target_ip, net_ntohs(p.to.port)}];
} else if (is_ipv4_mapped(target_ip)) {
IP ip4 = extract_ipv4(target_ip);
if (udp_bindings_.count({ip4, net_ntohs(p.to.port)})) {
udp_target = udp_bindings_[{ip4, net_ntohs(p.to.port)}];
}
}
}
}
}
if (!has_packet) {
break;
}
if (p.is_tcp) {
for (auto *it : tcp_targets) {
if (it->handle_packet(p)) {
break;
}
}
} else {
if (udp_target) {
udp_target->push_packet(std::move(p.data), p.from);
}
}
}
}
void NetworkUniverse::set_latency(uint64_t ms) { global_latency_ms_ = ms; }
void NetworkUniverse::set_verbose(bool verbose) { verbose_ = verbose; }
bool NetworkUniverse::is_verbose() const { return verbose_; }
void NetworkUniverse::add_filter(PacketFilter filter) { filters_.push_back(std::move(filter)); }
void NetworkUniverse::add_observer(PacketSink sink) { observers_.push_back(std::move(sink)); }
uint16_t NetworkUniverse::find_free_port(IP ip, uint16_t start)
{
std::lock_guard<std::recursive_mutex> lock(mutex_);
for (uint16_t port = start; port < 65535; ++port) {
if (!udp_bindings_.count({ip, port}) && !tcp_bindings_.count({ip, port}))
return port;
}
return 0;
}
} // namespace tox::test
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