tools/android/forwarder2/socket.cc

   1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "tools/android/forwarder2/socket.h"
   6
   7 #include <arpa/inet.h>
   8 #include <fcntl.h>
   9 #include <netdb.h>
  10 #include <netinet/in.h>
  11 #include <stdio.h>
  12 #include <string.h>
  13 #include <sys/socket.h>
  14 #include <sys/types.h>
  15 #include <unistd.h>
  16
  17 #include "base/logging.h"
  18 #include "base/posix/eintr_wrapper.h"
  19 #include "base/safe_strerror_posix.h"
  20 #include "tools/android/common/net.h"
  21 #include "tools/android/forwarder2/common.h"
  22
  23 namespace {
  24 const int kNoTimeout = -1;
  25 const int kConnectTimeOut = 10;  // Seconds.
  26
  27 bool FamilyIsTCP(int family) {
  28   return family == AF_INET || family == AF_INET6;
  29 }
  30 }  // namespace
  31
  32 namespace forwarder2 {
  33
  34 bool Socket::BindUnix(const std::string& path) {
  35   errno = 0;
  36   if (!InitUnixSocket(path) || !BindAndListen()) {
  37     Close();
  38     return false;
  39   }
  40   return true;
  41 }
  42
  43 bool Socket::BindTcp(const std::string& host, int port) {
  44   errno = 0;
  45   if (!InitTcpSocket(host, port) || !BindAndListen()) {
  46     Close();
  47     return false;
  48   }
  49   return true;
  50 }
  51
  52 bool Socket::ConnectUnix(const std::string& path) {
  53   errno = 0;
  54   if (!InitUnixSocket(path) || !Connect()) {
  55     Close();
  56     return false;
  57   }
  58   return true;
  59 }
  60
  61 bool Socket::ConnectTcp(const std::string& host, int port) {
  62   errno = 0;
  63   if (!InitTcpSocket(host, port) || !Connect()) {
  64     Close();
  65     return false;
  66   }
  67   return true;
  68 }
  69
  70 Socket::Socket()
  71     : socket_(-1),
  72       port_(0),
  73       socket_error_(false),
  74       family_(AF_INET),
  75       addr_ptr_(reinterpret_cast<sockaddr*>(&addr_.addr4)),
  76       addr_len_(sizeof(sockaddr)) {
  77   memset(&addr_, 0, sizeof(addr_));
  78 }
  79
  80 Socket::~Socket() {
  81   Close();
  82 }
  83
  84 void Socket::Shutdown() {
  85   if (!IsClosed()) {
  86     PRESERVE_ERRNO_HANDLE_EINTR(shutdown(socket_, SHUT_RDWR));
  87   }
  88 }
  89
  90 void Socket::Close() {
  91   if (!IsClosed()) {
  92     CloseFD(socket_);
  93     socket_ = -1;
  94   }
  95 }
  96
  97 bool Socket::InitSocketInternal() {
  98   socket_ = socket(family_, SOCK_STREAM, 0);
  99   if (socket_ < 0) {
 100     PLOG(ERROR) << "socket";
 101     return false;
 102   }
 103   tools::DisableNagle(socket_);
 104   int reuse_addr = 1;
 105   setsockopt(socket_, SOL_SOCKET, SO_REUSEADDR, &reuse_addr,
 106              sizeof(reuse_addr));
 107   if (!SetNonBlocking())
 108     return false;
 109   return true;
 110 }
 111
 112 bool Socket::SetNonBlocking() {
 113   const int flags = fcntl(socket_, F_GETFL);
 114   if (flags < 0) {
 115     PLOG(ERROR) << "fcntl";
 116     return false;
 117   }
 118   if (flags & O_NONBLOCK)
 119     return true;
 120   if (fcntl(socket_, F_SETFL, flags | O_NONBLOCK) < 0) {
 121     PLOG(ERROR) << "fcntl";
 122     return false;
 123   }
 124   return true;
 125 }
 126
 127 bool Socket::InitUnixSocket(const std::string& path) {
 128   static const size_t kPathMax = sizeof(addr_.addr_un.sun_path);
 129   // For abstract sockets we need one extra byte for the leading zero.
 130   if (path.size() + 2 /* '\0' */ > kPathMax) {
 131     LOG(ERROR) << "The provided path is too big to create a unix "
 132                << "domain socket: " << path;
 133     return false;
 134   }
 135   family_ = PF_UNIX;
 136   addr_.addr_un.sun_family = family_;
 137   // Copied from net/socket/unix_domain_socket_posix.cc
 138   // Convert the path given into abstract socket name. It must start with
 139   // the '\0' character, so we are adding it. |addr_len| must specify the
 140   // length of the structure exactly, as potentially the socket name may
 141   // have '\0' characters embedded (although we don't support this).
 142   // Note that addr_.addr_un.sun_path is already zero initialized.
 143   memcpy(addr_.addr_un.sun_path + 1, path.c_str(), path.size());
 144   addr_len_ = path.size() + offsetof(struct sockaddr_un, sun_path) + 1;
 145   addr_ptr_ = reinterpret_cast<sockaddr*>(&addr_.addr_un);
 146   return InitSocketInternal();
 147 }
 148
 149 bool Socket::InitTcpSocket(const std::string& host, int port) {
 150   port_ = port;
 151   if (host.empty()) {
 152     // Use localhost: INADDR_LOOPBACK
 153     family_ = AF_INET;
 154     addr_.addr4.sin_family = family_;
 155     addr_.addr4.sin_addr.s_addr = htonl(INADDR_LOOPBACK);
 156   } else if (!Resolve(host)) {
 157     return false;
 158   }
 159   CHECK(FamilyIsTCP(family_)) << "Invalid socket family.";
 160   if (family_ == AF_INET) {
 161     addr_.addr4.sin_port = htons(port_);
 162     addr_ptr_ = reinterpret_cast<sockaddr*>(&addr_.addr4);
 163     addr_len_ = sizeof(addr_.addr4);
 164   } else if (family_ == AF_INET6) {
 165     addr_.addr6.sin6_port = htons(port_);
 166     addr_ptr_ = reinterpret_cast<sockaddr*>(&addr_.addr6);
 167     addr_len_ = sizeof(addr_.addr6);
 168   }
 169   return InitSocketInternal();
 170 }
 171
 172 bool Socket::BindAndListen() {
 173   errno = 0;
 174   if (HANDLE_EINTR(bind(socket_, addr_ptr_, addr_len_)) < 0 ||
 175       HANDLE_EINTR(listen(socket_, SOMAXCONN)) < 0) {
 176     PLOG(ERROR) << "bind/listen";
 177     SetSocketError();
 178     return false;
 179   }
 180   if (port_ == 0 && FamilyIsTCP(family_)) {
 181     SockAddr addr;
 182     memset(&addr, 0, sizeof(addr));
 183     socklen_t addrlen = 0;
 184     sockaddr* addr_ptr = NULL;
 185     uint16* port_ptr = NULL;
 186     if (family_ == AF_INET) {
 187       addr_ptr = reinterpret_cast<sockaddr*>(&addr.addr4);
 188       port_ptr = &addr.addr4.sin_port;
 189       addrlen = sizeof(addr.addr4);
 190     } else if (family_ == AF_INET6) {
 191       addr_ptr = reinterpret_cast<sockaddr*>(&addr.addr6);
 192       port_ptr = &addr.addr6.sin6_port;
 193       addrlen = sizeof(addr.addr6);
 194     }
 195     errno = 0;
 196     if (getsockname(socket_, addr_ptr, &addrlen) != 0) {
 197       PLOG(ERROR) << "getsockname";
 198       SetSocketError();
 199       return false;
 200     }
 201     port_ = ntohs(*port_ptr);
 202   }
 203   return true;
 204 }
 205
 206 bool Socket::Accept(Socket* new_socket) {
 207   DCHECK(new_socket != NULL);
 208   if (!WaitForEvent(READ, kNoTimeout)) {
 209     SetSocketError();
 210     return false;
 211   }
 212   errno = 0;
 213   int new_socket_fd = HANDLE_EINTR(accept(socket_, NULL, NULL));
 214   if (new_socket_fd < 0) {
 215     SetSocketError();
 216     return false;
 217   }
 218   tools::DisableNagle(new_socket_fd);
 219   new_socket->socket_ = new_socket_fd;
 220   if (!new_socket->SetNonBlocking())
 221     return false;
 222   return true;
 223 }
 224
 225 bool Socket::Connect() {
 226   DCHECK(fcntl(socket_, F_GETFL) & O_NONBLOCK);
 227   errno = 0;
 228   if (HANDLE_EINTR(connect(socket_, addr_ptr_, addr_len_)) < 0 &&
 229       errno != EINPROGRESS) {
 230     SetSocketError();
 231     return false;
 232   }
 233   // Wait for connection to complete, or receive a notification.
 234   if (!WaitForEvent(WRITE, kConnectTimeOut)) {
 235     SetSocketError();
 236     return false;
 237   }
 238   int socket_errno;
 239   socklen_t opt_len = sizeof(socket_errno);
 240   if (getsockopt(socket_, SOL_SOCKET, SO_ERROR, &socket_errno, &opt_len) < 0) {
 241     PLOG(ERROR) << "getsockopt()";
 242     SetSocketError();
 243     return false;
 244   }
 245   if (socket_errno != 0) {
 246     LOG(ERROR) << "Could not connect to host: " << safe_strerror(socket_errno);
 247     SetSocketError();
 248     return false;
 249   }
 250   return true;
 251 }
 252
 253 bool Socket::Resolve(const std::string& host) {
 254   struct addrinfo hints;
 255   struct addrinfo* res;
 256   memset(&hints, 0, sizeof(hints));
 257   hints.ai_family = AF_UNSPEC;
 258   hints.ai_socktype = SOCK_STREAM;
 259   hints.ai_flags |= AI_CANONNAME;
 260
 261   int errcode = getaddrinfo(host.c_str(), NULL, &hints, &res);
 262   if (errcode != 0) {
 263     errno = 0;
 264     SetSocketError();
 265     freeaddrinfo(res);
 266     return false;
 267   }
 268   family_ = res->ai_family;
 269   switch (res->ai_family) {
 270     case AF_INET:
 271       memcpy(&addr_.addr4,
 272              reinterpret_cast<sockaddr_in*>(res->ai_addr),
 273              sizeof(sockaddr_in));
 274       break;
 275     case AF_INET6:
 276       memcpy(&addr_.addr6,
 277              reinterpret_cast<sockaddr_in6*>(res->ai_addr),
 278              sizeof(sockaddr_in6));
 279       break;
 280   }
 281   freeaddrinfo(res);
 282   return true;
 283 }
 284
 285 int Socket::GetPort() {
 286   if (!FamilyIsTCP(family_)) {
 287     LOG(ERROR) << "Can't call GetPort() on an unix domain socket.";
 288     return 0;
 289   }
 290   return port_;
 291 }
 292
 293 int Socket::ReadNumBytes(void* buffer, size_t num_bytes) {
 294   size_t bytes_read = 0;
 295   int ret = 1;
 296   while (bytes_read < num_bytes && ret > 0) {
 297     ret = Read(static_cast<char*>(buffer) + bytes_read, num_bytes - bytes_read);
 298     if (ret >= 0)
 299       bytes_read += ret;
 300   }
 301   return bytes_read;
 302 }
 303
 304 void Socket::SetSocketError() {
 305   socket_error_ = true;
 306   DCHECK_NE(EAGAIN, errno);
 307   DCHECK_NE(EWOULDBLOCK, errno);
 308   Close();
 309 }
 310
 311 int Socket::Read(void* buffer, size_t buffer_size) {
 312   if (!WaitForEvent(READ, kNoTimeout)) {
 313     SetSocketError();
 314     return 0;
 315   }
 316   int ret = HANDLE_EINTR(read(socket_, buffer, buffer_size));
 317   if (ret < 0) {
 318     PLOG(ERROR) << "read";
 319     SetSocketError();
 320   }
 321   return ret;
 322 }
 323
 324 int Socket::NonBlockingRead(void* buffer, size_t buffer_size) {
 325   DCHECK(fcntl(socket_, F_GETFL) & O_NONBLOCK);
 326   int ret = HANDLE_EINTR(read(socket_, buffer, buffer_size));
 327   if (ret < 0) {
 328     PLOG(ERROR) << "read";
 329     SetSocketError();
 330   }
 331   return ret;
 332 }
 333
 334 int Socket::Write(const void* buffer, size_t count) {
 335   if (!WaitForEvent(WRITE, kNoTimeout)) {
 336     SetSocketError();
 337     return 0;
 338   }
 339   int ret = HANDLE_EINTR(send(socket_, buffer, count, MSG_NOSIGNAL));
 340   if (ret < 0) {
 341     PLOG(ERROR) << "send";
 342     SetSocketError();
 343   }
 344   return ret;
 345 }
 346
 347 int Socket::NonBlockingWrite(const void* buffer, size_t count) {
 348   DCHECK(fcntl(socket_, F_GETFL) & O_NONBLOCK);
 349   int ret = HANDLE_EINTR(send(socket_, buffer, count, MSG_NOSIGNAL));
 350   if (ret < 0) {
 351     PLOG(ERROR) << "send";
 352     SetSocketError();
 353   }
 354   return ret;
 355 }
 356
 357 int Socket::WriteString(const std::string& buffer) {
 358   return WriteNumBytes(buffer.c_str(), buffer.size());
 359 }
 360
 361 void Socket::AddEventFd(int event_fd) {
 362   Event event;
 363   event.fd = event_fd;
 364   event.was_fired = false;
 365   events_.push_back(event);
 366 }
 367
 368 bool Socket::DidReceiveEventOnFd(int fd) const {
 369   for (size_t i = 0; i < events_.size(); ++i)
 370     if (events_[i].fd == fd)
 371       return events_[i].was_fired;
 372   return false;
 373 }
 374
 375 bool Socket::DidReceiveEvent() const {
 376   for (size_t i = 0; i < events_.size(); ++i)
 377     if (events_[i].was_fired)
 378       return true;
 379   return false;
 380 }
 381
 382 int Socket::WriteNumBytes(const void* buffer, size_t num_bytes) {
 383   size_t bytes_written = 0;
 384   int ret = 1;
 385   while (bytes_written < num_bytes && ret > 0) {
 386     ret = Write(static_cast<const char*>(buffer) + bytes_written,
 387                 num_bytes - bytes_written);
 388     if (ret >= 0)
 389       bytes_written += ret;
 390   }
 391   return bytes_written;
 392 }
 393
 394 bool Socket::WaitForEvent(EventType type, int timeout_secs) {
 395   if (socket_ == -1)
 396     return true;
 397   DCHECK(fcntl(socket_, F_GETFL) & O_NONBLOCK);
 398   fd_set read_fds;
 399   fd_set write_fds;
 400   FD_ZERO(&read_fds);
 401   FD_ZERO(&write_fds);
 402   if (type == READ)
 403     FD_SET(socket_, &read_fds);
 404   else
 405     FD_SET(socket_, &write_fds);
 406   for (size_t i = 0; i < events_.size(); ++i)
 407     FD_SET(events_[i].fd, &read_fds);
 408   timeval tv = {};
 409   timeval* tv_ptr = NULL;
 410   if (timeout_secs > 0) {
 411     tv.tv_sec = timeout_secs;
 412     tv.tv_usec = 0;
 413     tv_ptr = &tv;
 414   }
 415   int max_fd = socket_;
 416   for (size_t i = 0; i < events_.size(); ++i)
 417     if (events_[i].fd > max_fd)
 418       max_fd = events_[i].fd;
 419   if (HANDLE_EINTR(
 420           select(max_fd + 1, &read_fds, &write_fds, NULL, tv_ptr)) <= 0) {
 421     PLOG(ERROR) << "select";
 422     return false;
 423   }
 424   bool event_was_fired = false;
 425   for (size_t i = 0; i < events_.size(); ++i) {
 426     if (FD_ISSET(events_[i].fd, &read_fds)) {
 427       events_[i].was_fired = true;
 428       event_was_fired = true;
 429     }
 430   }
 431   return !event_was_fired;
 432 }
 433
 434 // static
 435 pid_t Socket::GetUnixDomainSocketProcessOwner(const std::string& path) {
 436   Socket socket;
 437   if (!socket.ConnectUnix(path))
 438     return -1;
 439   ucred ucred;
 440   socklen_t len = sizeof(ucred);
 441   if (getsockopt(socket.socket_, SOL_SOCKET, SO_PEERCRED, &ucred, &len) == -1) {
 442     CHECK_NE(ENOPROTOOPT, errno);
 443     return -1;
 444   }
 445   return ucred.pid;
 446 }
 447
 448 }  // namespace forwarder2