tunsafe-clang15/network_bsd_mt.cpp
Ludvig Strigeus 3f1b435b4e Handle packet overload on non-windows
- Also ensure RunAllMainThreadScheduled(); gets called on non-windows
2018-08-12 12:43:53 +02:00

585 lines
13 KiB
C++

// SPDX-License-Identifier: AGPL-1.0-only
// Copyright (C) 2018 Ludvig Strigeus <info@tunsafe.com>. All Rights Reserved.
// Note: This is an experimental implementation that doesn't work, there's no way
// for the alarm signal to interrupt the tunsafe main thread.
#include "network_bsd_common.h"
#include "tunsafe_endian.h"
#include "tunsafe_config.h"
#include "tunsafe_threading.h"
#include "util.h"
#include <stdio.h>
#include <unistd.h>
#include <fcntl.h>
#include <sys/ioctl.h>
#include <net/if.h>
#include <netinet/in.h>
#include <string.h>
#include <arpa/inet.h>
#include <sys/stat.h>
#include <stdlib.h>
#include <errno.h>
#include <assert.h>
#include <signal.h>
#include <pthread.h>
static Packet *freelist;
void FreePacket(Packet *packet) {
free(packet);
// packet->next = freelist;
// freelist = packet;
}
Packet *AllocPacket() {
Packet *p = NULL;// freelist;
if (p) {
freelist = p->next;
} else {
p = (Packet*)malloc(kPacketAllocSize);
if (p == NULL) {
RERROR("Allocation failure");
abort();
}
}
p->data = p->data_buf + Packet::HEADROOM_BEFORE;
p->size = 0;
return p;
}
void FreePackets() {
Packet *p;
while ( (p = freelist ) != NULL) {
freelist = p->next;
free(p);
}
}
class WorkerLoop {
public:
WorkerLoop();
~WorkerLoop();
bool Initialize(WireguardProcessor *processor);
void *ThreadMain();
void StartThread();
void StopThread();
void NotifyStop();
enum {
TARGET_UDP, TARGET_TUN
};
void HandleUdpPacket(Packet *packet) {
HandlePacket(packet, TARGET_UDP);
}
void HandleTunPacket(Packet *packet) {
HandlePacket(packet, TARGET_TUN);
}
void HandleSigAlrm() {
got_sig_alarm_ = true;
}
private:
static void *ThreadMainStatic(void *x);
void HandlePacket(Packet *packet, int target);
WireguardProcessor *processor_;
pthread_t tid_;
Packet *queue_, **queue_end_;
bool shutting_down_;
bool got_sig_alarm_;
Mutex lock_;
pthread_cond_t cond_;
};
// Handles the threads that read/write to the udp socket.
class UdpLoop {
public:
UdpLoop();
~UdpLoop();
bool Initialize(int listen_port, WorkerLoop *worker);
void Start();
void Stop();
void WriteUdpPacket(Packet *packet);
private:
static void *ReaderMainStatic(void *x);
static void *WriterMainStatic(void *x);
void *ReaderMain();
void *WriterMain();
int fd_;
WorkerLoop *worker_;
pthread_t read_tid_, write_tid_;
Packet *queue_, **queue_end_;
bool shutting_down_;
Mutex lock_;
pthread_cond_t cond_;
};
// Handles the threads that read/write to the tun socket.
class TunLoop {
public:
TunLoop();
~TunLoop();
bool Initialize(char devname[16], WorkerLoop *worker);
void Start();
void Stop();
void WriteTunPacket(Packet *packet);
private:
static void *ReaderMainStatic(void *x);
static void *WriterMainStatic(void *x);
void *ReaderMain();
void *WriterMain();
int fd_;
bool shutting_down_;
WorkerLoop *worker_;
pthread_t read_tid_, write_tid_;
Packet *queue_, **queue_end_;
Mutex lock_;
pthread_cond_t cond_;
};
WorkerLoop::WorkerLoop() {
queue_end_ = &queue_;
queue_ = NULL;
tid_ = 0;
shutting_down_ = false;
got_sig_alarm_ = false;
processor_ = NULL;
if (pthread_cond_init(&cond_, NULL) != 0)
tunsafe_die("pthread_cond_init failed");
}
WorkerLoop::~WorkerLoop() {
pthread_cond_destroy(&cond_);
}
bool WorkerLoop::Initialize(WireguardProcessor *processor) {
processor_ = processor;
return true;
}
void WorkerLoop::StartThread() {
assert(tid_ == 0);
if (pthread_create(&tid_, NULL, &ThreadMainStatic, this) != 0)
tunsafe_die("pthread_create failed");
}
void WorkerLoop::StopThread() {
lock_.Acquire();
shutting_down_ = true;
lock_.Release();
if (tid_) {
void *x;
pthread_join(tid_, &x);
tid_ = 0;
}
}
// This is called from signal handler so cannot block etc.
void WorkerLoop::NotifyStop() {
shutting_down_ = true;
}
void WorkerLoop::HandlePacket(Packet *packet, int target) {
// RINFO("WorkerLoop::HandlePacket");
packet->post_target = target;
lock_.Acquire();
Packet *old_queue = queue_;
*queue_end_ = packet;
queue_end_ = &packet->next;
packet->next = NULL;
if (old_queue == NULL) {
lock_.Release();
pthread_cond_signal(&cond_);
} else {
lock_.Release();
}
}
void *WorkerLoop::ThreadMainStatic(void *x) {
return ((WorkerLoop*)x)->ThreadMain();
}
void *WorkerLoop::ThreadMain() {
Packet *packet_queue;
lock_.Acquire();
for (;;) {
// Grab the whole list
for (;;) {
while (got_sig_alarm_) {
got_sig_alarm_ = false;
lock_.Release();
processor_->SecondLoop();
processor_->RunAllMainThreadScheduled();
lock_.Acquire();
}
if (shutting_down_ || queue_ != NULL)
break;
pthread_cond_wait(&cond_, lock_.impl());
}
if (shutting_down_)
break;
packet_queue = queue_;
queue_ = NULL;
queue_end_ = &queue_;
lock_.Release();
// And send all items in the list
while (packet_queue != NULL) {
Packet *next = packet_queue->next;
if (packet_queue->post_target == TARGET_TUN) {
processor_->HandleTunPacket(packet_queue);
} else {
processor_->HandleUdpPacket(packet_queue, false);
}
packet_queue = next;
}
processor_->RunAllMainThreadScheduled();
lock_.Acquire();
}
lock_.Release();
return NULL;
}
UdpLoop::UdpLoop() {
fd_ = -1;
read_tid_ = 0;
write_tid_ = 0;
shutting_down_ = false;
worker_ = NULL;
queue_ = NULL;
queue_end_ = &queue_;
if (pthread_cond_init(&cond_, NULL) != 0)
tunsafe_die("pthread_cond_init failed");
}
UdpLoop::~UdpLoop() {
if (fd_ != -1)
close(fd_);
pthread_cond_destroy(&cond_);
}
bool UdpLoop::Initialize(int listen_port, WorkerLoop *worker) {
int fd = open_udp(listen_port);
if (fd < 0) { RERROR("Error opening udp"); return false; }
fcntl(fd, F_SETFD, FD_CLOEXEC);
fd_ = fd;
worker_ = worker;
return true;
}
void UdpLoop::Start() {
if (pthread_create(&read_tid_, NULL, &ReaderMainStatic, this) != 0)
tunsafe_die("pthread_create failed");
if (pthread_create(&write_tid_, NULL, &WriterMainStatic, this) != 0)
tunsafe_die("pthread_create failed");
}
void UdpLoop::Stop() {
void *x;
lock_.Acquire();
shutting_down_ = true;
lock_.Release();
pthread_cond_signal(&cond_);
pthread_kill(read_tid_, SIGUSR1);
pthread_kill(write_tid_, SIGUSR1);
pthread_join(read_tid_, &x);
pthread_join(write_tid_, &x);
read_tid_ = 0;
write_tid_ = 0;
}
void *UdpLoop::ReaderMainStatic(void *x) {
SetThreadName("tunsafe-ur");
return ((UdpLoop*)x)->ReaderMain();
}
void *UdpLoop::WriterMainStatic(void *x) {
SetThreadName("tunsafe-uw");
return ((UdpLoop*)x)->WriterMain();
}
void *UdpLoop::ReaderMain() {
Packet *packet;
socklen_t sin_len;
int r;
while (!shutting_down_) {
packet = AllocPacket();
sin_len = sizeof(packet->addr.sin);
r = recvfrom(fd_, packet->data, kPacketCapacity, 0, (sockaddr*)&packet->addr.sin, &sin_len);
if (r < 0) {
FreePacket(packet);
if (shutting_down_)
break;
RERROR("ReadMain failed %d", errno);
} else {
packet->size = r;
worker_->HandleUdpPacket(packet);
}
}
return NULL;
}
void *UdpLoop::WriterMain() {
Packet *queue;
lock_.Acquire();
for (;;) {
// Grab the whole list
while (!shutting_down_ && queue_ == NULL)
pthread_cond_wait(&cond_, lock_.impl());
if (shutting_down_)
break;
queue = queue_;
queue_ = NULL;
queue_end_ = &queue_;
lock_.Release();
// And send all items in the list
while (queue != NULL) {
int r = sendto(fd_, queue->data, queue->size, 0,
(sockaddr*)&queue->addr.sin, sizeof(queue->addr.sin));
if (r != queue->size) {
if (errno != ENOBUFS)
RERROR("WriterMain failed: %d", errno);
} else {
// RINFO("WRote udp packet!");
}
Packet *to_free = queue;
queue = queue->next;
FreePacket(to_free);
}
lock_.Acquire();
}
lock_.Release();
return NULL;
}
void UdpLoop::WriteUdpPacket(Packet *packet) {
// RINFO("write udp packet to queue!");
packet->next = NULL;
lock_.Acquire();
Packet *old_queue = queue_;
*queue_end_ = packet;
queue_end_ = &packet->next;
if (old_queue == NULL) {
lock_.Release();
pthread_cond_signal(&cond_);
} else {
lock_.Release();
}
}
TunLoop::TunLoop() {
fd_ = -1;
shutting_down_ = false;
worker_ = NULL;
read_tid_ = 0;
write_tid_ = 0;
queue_ = NULL;
queue_end_ = &queue_;
if (pthread_cond_init(&cond_, NULL) != 0)
tunsafe_die("pthread_cond_init failed");
}
TunLoop::~TunLoop() {
if (fd_ != -1)
close(fd_);
pthread_cond_destroy(&cond_);
}
bool TunLoop::Initialize(char devname[16], WorkerLoop *worker) {
int fd = open_tun(devname, 16);
if (fd < 0) { RERROR("Error opening tun"); return false; }
fcntl(fd, F_SETFD, FD_CLOEXEC);
fd_ = fd;
worker_ = worker;
return true;
}
void TunLoop::Start() {
if (pthread_create(&read_tid_, NULL, &ReaderMainStatic, this) != 0)
tunsafe_die("pthread_create failed");
if (pthread_create(&write_tid_, NULL, &WriterMainStatic, this) != 0)
tunsafe_die("pthread_create failed");
}
void TunLoop::Stop() {
void *x;
lock_.Acquire();
shutting_down_ = true;
lock_.Release();
pthread_kill(read_tid_, SIGUSR1);
pthread_kill(write_tid_, SIGUSR1);
pthread_join(read_tid_, &x);
pthread_join(write_tid_, &x);
read_tid_ = 0;
write_tid_ = 0;
}
void *TunLoop::ReaderMainStatic(void *x) {
SetThreadName("tunsafe-tr");
return ((TunLoop*)x)->ReaderMain();
}
void *TunLoop::WriterMainStatic(void *x) {
SetThreadName("tunsafe-tw");
return ((TunLoop*)x)->WriterMain();
}
void *TunLoop::ReaderMain() {
Packet *packet = AllocPacket();
while (!shutting_down_) {
int r = read(fd_, packet->data - TUN_PREFIX_BYTES, kPacketCapacity + TUN_PREFIX_BYTES);
if (r >= 0) {
packet->size = r - TUN_PREFIX_BYTES;
if (r >= TUN_PREFIX_BYTES && (!TUN_PREFIX_BYTES || ReadBE32(packet->data - TUN_PREFIX_BYTES) == AF_INET)) {
worker_->HandleTunPacket(packet);
packet = AllocPacket();
}
}
}
return NULL;
}
void *TunLoop::WriterMain() {
Packet *queue;
lock_.Acquire();
for (;;) {
// Grab the whole list
while (!shutting_down_ && queue_ == NULL) {
pthread_cond_wait(&cond_, lock_.impl());
}
if (shutting_down_)
break;
queue = queue_;
queue_ = NULL;
queue_end_ = &queue_;
lock_.Release();
// And send all items in the list
while (queue != NULL) {
if (TUN_PREFIX_BYTES)
WriteBE32(queue->data - TUN_PREFIX_BYTES, AF_INET);
int r = write(fd_, queue->data - TUN_PREFIX_BYTES, queue->size + TUN_PREFIX_BYTES);
if (r != queue->size + TUN_PREFIX_BYTES) {
RERROR("WriterMain failed: %d", errno);
break;
}
Packet *to_free = queue;
queue = queue->next;
FreePacket(to_free);
}
lock_.Acquire();
}
lock_.Release();
return NULL;
}
void TunLoop::WriteTunPacket(Packet *packet) {
packet->next = NULL;
lock_.Acquire();
Packet *old_queue = queue_;
*queue_end_ = packet;
queue_end_ = &packet->next;
if (old_queue == NULL) {
lock_.Release();
pthread_cond_signal(&cond_);
} else {
lock_.Release();
}
}
class TunsafeBackendBsdImpl : public TunsafeBackendBsd {
public:
TunsafeBackendBsdImpl();
virtual ~TunsafeBackendBsdImpl();
// -- from TunInterface
virtual void WriteTunPacket(Packet *packet) override;
// -- from UdpInterface
virtual bool Initialize(int listen_port) override;
virtual void WriteUdpPacket(Packet *packet) override;
virtual void HandleSigAlrm() override { worker_.HandleSigAlrm(); }
virtual void HandleExit() override { worker_.NotifyStop(); }
virtual bool InitializeTun(char devname[16]) override;
virtual void RunLoopInner() override;
private:
WorkerLoop worker_;
UdpLoop udp_;
TunLoop tun_;
};
TunsafeBackendBsdImpl::TunsafeBackendBsdImpl() {
}
TunsafeBackendBsdImpl::~TunsafeBackendBsdImpl() {
}
bool TunsafeBackendBsdImpl::InitializeTun(char devname[16]) {
return tun_.Initialize(devname, &worker_);
}
void TunsafeBackendBsdImpl::WriteTunPacket(Packet *packet) override {
tun_.WriteTunPacket(packet);
}
// Called to initialize udp
bool TunsafeBackendBsdImpl::Initialize(int listen_port) override {
return udp_.Initialize(listen_port, &worker_);
}
void TunsafeBackendBsdImpl::WriteUdpPacket(Packet *packet) override {
udp_.WriteUdpPacket(packet);
}
void TunsafeBackendBsdImpl::RunLoopInner() {
worker_.Initialize(processor_);
udp_.Start();
tun_.Start();
worker_.ThreadMain();
tun_.Stop();
udp_.Stop();
}
TunsafeBackendBsd *CreateTunsafeBackendBsd() {
return new TunsafeBackendBsdImpl;
}