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Socket.cpp
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1 //===-- Socket.cpp ----------------------------------------------*- C++ -*-===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 
9 #include "lldb/Host/Socket.h"
10 
11 #include "lldb/Host/Config.h"
12 #include "lldb/Host/Host.h"
17 #include "lldb/Utility/Log.h"
19 
20 #include "llvm/ADT/STLExtras.h"
21 #include "llvm/Support/Errno.h"
22 #include "llvm/Support/Error.h"
23 #include "llvm/Support/WindowsError.h"
24 
25 #ifndef LLDB_DISABLE_POSIX
27 
28 #include <arpa/inet.h>
29 #include <netdb.h>
30 #include <netinet/in.h>
31 #include <netinet/tcp.h>
32 #include <sys/socket.h>
33 #include <sys/un.h>
34 #include <unistd.h>
35 #endif
36 
37 #ifdef __linux__
39 #endif
40 
41 #ifdef __ANDROID__
42 #include <arpa/inet.h>
43 #include <asm-generic/errno-base.h>
44 #include <errno.h>
45 #include <linux/tcp.h>
46 #include <fcntl.h>
47 #include <sys/syscall.h>
48 #include <unistd.h>
49 #endif // __ANDROID__
50 
51 using namespace lldb;
52 using namespace lldb_private;
53 
54 #if defined(_WIN32)
55 typedef const char *set_socket_option_arg_type;
56 typedef char *get_socket_option_arg_type;
57 const NativeSocket Socket::kInvalidSocketValue = INVALID_SOCKET;
58 #else // #if defined(_WIN32)
59 typedef const void *set_socket_option_arg_type;
61 const NativeSocket Socket::kInvalidSocketValue = -1;
62 #endif // #if defined(_WIN32)
63 
64 namespace {
65 
66 bool IsInterrupted() {
67 #if defined(_WIN32)
68  return ::WSAGetLastError() == WSAEINTR;
69 #else
70  return errno == EINTR;
71 #endif
72 }
73 }
74 
75 Socket::Socket(SocketProtocol protocol, bool should_close,
76  bool child_processes_inherit)
77  : IOObject(eFDTypeSocket, should_close), m_protocol(protocol),
78  m_socket(kInvalidSocketValue),
79  m_child_processes_inherit(child_processes_inherit) {}
80 
82 
84 #if defined(_WIN32)
85  auto wVersion = WINSOCK_VERSION;
86  WSADATA wsaData;
87  int err = ::WSAStartup(wVersion, &wsaData);
88  if (err == 0) {
89  if (wsaData.wVersion < wVersion) {
90  WSACleanup();
91  return llvm::make_error<llvm::StringError>(
92  "WSASock version is not expected.", llvm::inconvertibleErrorCode());
93  }
94  } else {
95  return llvm::errorCodeToError(llvm::mapWindowsError(::WSAGetLastError()));
96  }
97 #endif
98 
99  return llvm::Error::success();
100 }
101 
103 #if defined(_WIN32)
104  ::WSACleanup();
105 #endif
106 }
107 
108 std::unique_ptr<Socket> Socket::Create(const SocketProtocol protocol,
109  bool child_processes_inherit,
110  Status &error) {
111  error.Clear();
112 
113  std::unique_ptr<Socket> socket_up;
114  switch (protocol) {
115  case ProtocolTcp:
116  socket_up =
117  llvm::make_unique<TCPSocket>(true, child_processes_inherit);
118  break;
119  case ProtocolUdp:
120  socket_up =
121  llvm::make_unique<UDPSocket>(true, child_processes_inherit);
122  break;
123  case ProtocolUnixDomain:
124 #ifndef LLDB_DISABLE_POSIX
125  socket_up =
126  llvm::make_unique<DomainSocket>(true, child_processes_inherit);
127 #else
128  error.SetErrorString(
129  "Unix domain sockets are not supported on this platform.");
130 #endif
131  break;
133 #ifdef __linux__
134  socket_up =
135  llvm::make_unique<AbstractSocket>(child_processes_inherit);
136 #else
137  error.SetErrorString(
138  "Abstract domain sockets are not supported on this platform.");
139 #endif
140  break;
141  }
142 
143  if (error.Fail())
144  socket_up.reset();
145 
146  return socket_up;
147 }
148 
149 Status Socket::TcpConnect(llvm::StringRef host_and_port,
150  bool child_processes_inherit, Socket *&socket) {
152  if (log)
153  log->Printf("Socket::%s (host/port = %s)", __FUNCTION__,
154  host_and_port.str().c_str());
155 
156  Status error;
157  std::unique_ptr<Socket> connect_socket(
158  Create(ProtocolTcp, child_processes_inherit, error));
159  if (error.Fail())
160  return error;
161 
162  error = connect_socket->Connect(host_and_port);
163  if (error.Success())
164  socket = connect_socket.release();
165 
166  return error;
167 }
168 
169 Status Socket::TcpListen(llvm::StringRef host_and_port,
170  bool child_processes_inherit, Socket *&socket,
171  Predicate<uint16_t> *predicate, int backlog) {
173  if (log)
174  log->Printf("Socket::%s (%s)", __FUNCTION__, host_and_port.str().c_str());
175 
176  Status error;
177  std::string host_str;
178  std::string port_str;
179  int32_t port = INT32_MIN;
180  if (!DecodeHostAndPort(host_and_port, host_str, port_str, port, &error))
181  return error;
182 
183  std::unique_ptr<TCPSocket> listen_socket(
184  new TCPSocket(true, child_processes_inherit));
185  if (error.Fail())
186  return error;
187 
188  error = listen_socket->Listen(host_and_port, backlog);
189  if (error.Success()) {
190  // We were asked to listen on port zero which means we must now read the
191  // actual port that was given to us as port zero is a special code for
192  // "find an open port for me".
193  if (port == 0)
194  port = listen_socket->GetLocalPortNumber();
195 
196  // Set the port predicate since when doing a listen://<host>:<port> it
197  // often needs to accept the incoming connection which is a blocking system
198  // call. Allowing access to the bound port using a predicate allows us to
199  // wait for the port predicate to be set to a non-zero value from another
200  // thread in an efficient manor.
201  if (predicate)
202  predicate->SetValue(port, eBroadcastAlways);
203  socket = listen_socket.release();
204  }
205 
206  return error;
207 }
208 
209 Status Socket::UdpConnect(llvm::StringRef host_and_port,
210  bool child_processes_inherit, Socket *&socket) {
212  if (log)
213  log->Printf("Socket::%s (host/port = %s)", __FUNCTION__,
214  host_and_port.str().c_str());
215 
216  return UDPSocket::Connect(host_and_port, child_processes_inherit, socket);
217 }
218 
219 Status Socket::UnixDomainConnect(llvm::StringRef name,
220  bool child_processes_inherit,
221  Socket *&socket) {
222  Status error;
223  std::unique_ptr<Socket> connect_socket(
224  Create(ProtocolUnixDomain, child_processes_inherit, error));
225  if (error.Fail())
226  return error;
227 
228  error = connect_socket->Connect(name);
229  if (error.Success())
230  socket = connect_socket.release();
231 
232  return error;
233 }
234 
235 Status Socket::UnixDomainAccept(llvm::StringRef name,
236  bool child_processes_inherit, Socket *&socket) {
237  Status error;
238  std::unique_ptr<Socket> listen_socket(
239  Create(ProtocolUnixDomain, child_processes_inherit, error));
240  if (error.Fail())
241  return error;
242 
243  error = listen_socket->Listen(name, 5);
244  if (error.Fail())
245  return error;
246 
247  error = listen_socket->Accept(socket);
248  return error;
249 }
250 
251 Status Socket::UnixAbstractConnect(llvm::StringRef name,
252  bool child_processes_inherit,
253  Socket *&socket) {
254  Status error;
255  std::unique_ptr<Socket> connect_socket(
256  Create(ProtocolUnixAbstract, child_processes_inherit, error));
257  if (error.Fail())
258  return error;
259 
260  error = connect_socket->Connect(name);
261  if (error.Success())
262  socket = connect_socket.release();
263  return error;
264 }
265 
266 Status Socket::UnixAbstractAccept(llvm::StringRef name,
267  bool child_processes_inherit,
268  Socket *&socket) {
269  Status error;
270  std::unique_ptr<Socket> listen_socket(
271  Create(ProtocolUnixAbstract, child_processes_inherit, error));
272  if (error.Fail())
273  return error;
274 
275  error = listen_socket->Listen(name, 5);
276  if (error.Fail())
277  return error;
278 
279  error = listen_socket->Accept(socket);
280  return error;
281 }
282 
283 bool Socket::DecodeHostAndPort(llvm::StringRef host_and_port,
284  std::string &host_str, std::string &port_str,
285  int32_t &port, Status *error_ptr) {
286  static RegularExpression g_regex(
287  llvm::StringRef("([^:]+|\\[[0-9a-fA-F:]+.*\\]):([0-9]+)"));
288  RegularExpression::Match regex_match(2);
289  if (g_regex.Execute(host_and_port, &regex_match)) {
290  if (regex_match.GetMatchAtIndex(host_and_port, 1, host_str) &&
291  regex_match.GetMatchAtIndex(host_and_port, 2, port_str)) {
292  // IPv6 addresses are wrapped in [] when specified with ports
293  if (host_str.front() == '[' && host_str.back() == ']')
294  host_str = host_str.substr(1, host_str.size() - 2);
295  bool ok = false;
296  port = StringConvert::ToUInt32(port_str.c_str(), UINT32_MAX, 10, &ok);
297  if (ok && port <= UINT16_MAX) {
298  if (error_ptr)
299  error_ptr->Clear();
300  return true;
301  }
302  // port is too large
303  if (error_ptr)
304  error_ptr->SetErrorStringWithFormat(
305  "invalid host:port specification: '%s'",
306  host_and_port.str().c_str());
307  return false;
308  }
309  }
310 
311  // If this was unsuccessful, then check if it's simply a signed 32-bit
312  // integer, representing a port with an empty host.
313  host_str.clear();
314  port_str.clear();
315  if (to_integer(host_and_port, port, 10) && port < UINT16_MAX) {
316  port_str = host_and_port;
317  if (error_ptr)
318  error_ptr->Clear();
319  return true;
320  }
321 
322  if (error_ptr)
323  error_ptr->SetErrorStringWithFormat("invalid host:port specification: '%s'",
324  host_and_port.str().c_str());
325  return false;
326 }
327 
329  // TODO: On Windows, use WSAEventSelect
330  return m_socket;
331 }
332 
333 Status Socket::Read(void *buf, size_t &num_bytes) {
334  Status error;
335  int bytes_received = 0;
336  do {
337  bytes_received = ::recv(m_socket, static_cast<char *>(buf), num_bytes, 0);
338  } while (bytes_received < 0 && IsInterrupted());
339 
340  if (bytes_received < 0) {
341  SetLastError(error);
342  num_bytes = 0;
343  } else
344  num_bytes = bytes_received;
345 
347  if (log) {
348  log->Printf("%p Socket::Read() (socket = %" PRIu64
349  ", src = %p, src_len = %" PRIu64 ", flags = 0) => %" PRIi64
350  " (error = %s)",
351  static_cast<void *>(this), static_cast<uint64_t>(m_socket), buf,
352  static_cast<uint64_t>(num_bytes),
353  static_cast<int64_t>(bytes_received), error.AsCString());
354  }
355 
356  return error;
357 }
358 
359 Status Socket::Write(const void *buf, size_t &num_bytes) {
360  Status error;
361  int bytes_sent = 0;
362  do {
363  bytes_sent = Send(buf, num_bytes);
364  } while (bytes_sent < 0 && IsInterrupted());
365 
366  if (bytes_sent < 0) {
367  SetLastError(error);
368  num_bytes = 0;
369  } else
370  num_bytes = bytes_sent;
371 
373  if (log) {
374  log->Printf("%p Socket::Write() (socket = %" PRIu64
375  ", src = %p, src_len = %" PRIu64 ", flags = 0) => %" PRIi64
376  " (error = %s)",
377  static_cast<void *>(this), static_cast<uint64_t>(m_socket), buf,
378  static_cast<uint64_t>(num_bytes),
379  static_cast<int64_t>(bytes_sent), error.AsCString());
380  }
381 
382  return error;
383 }
384 
386  Status error;
387  return error;
388 }
389 
391  Status error;
392  if (!IsValid() || !m_should_close_fd)
393  return error;
394 
396  if (log)
397  log->Printf("%p Socket::Close (fd = %i)", static_cast<void *>(this),
398  m_socket);
399 
400 #if defined(_WIN32)
401  bool success = !!closesocket(m_socket);
402 #else
403  bool success = !!::close(m_socket);
404 #endif
405  // A reference to a FD was passed in, set it to an invalid value
407  if (!success) {
408  SetLastError(error);
409  }
410 
411  return error;
412 }
413 
414 int Socket::GetOption(int level, int option_name, int &option_value) {
415  get_socket_option_arg_type option_value_p =
416  reinterpret_cast<get_socket_option_arg_type>(&option_value);
417  socklen_t option_value_size = sizeof(int);
418  return ::getsockopt(m_socket, level, option_name, option_value_p,
419  &option_value_size);
420 }
421 
422 int Socket::SetOption(int level, int option_name, int option_value) {
423  set_socket_option_arg_type option_value_p =
424  reinterpret_cast<get_socket_option_arg_type>(&option_value);
425  return ::setsockopt(m_socket, level, option_name, option_value_p,
426  sizeof(option_value));
427 }
428 
429 size_t Socket::Send(const void *buf, const size_t num_bytes) {
430  return ::send(m_socket, static_cast<const char *>(buf), num_bytes, 0);
431 }
432 
434 #if defined(_WIN32)
435  error.SetError(::WSAGetLastError(), lldb::eErrorTypeWin32);
436 #else
437  error.SetErrorToErrno();
438 #endif
439 }
440 
441 NativeSocket Socket::CreateSocket(const int domain, const int type,
442  const int protocol,
443  bool child_processes_inherit, Status &error) {
444  error.Clear();
445  auto socket_type = type;
446 #ifdef SOCK_CLOEXEC
447  if (!child_processes_inherit)
448  socket_type |= SOCK_CLOEXEC;
449 #endif
450  auto sock = ::socket(domain, socket_type, protocol);
451  if (sock == kInvalidSocketValue)
452  SetLastError(error);
453 
454  return sock;
455 }
456 
457 NativeSocket Socket::AcceptSocket(NativeSocket sockfd, struct sockaddr *addr,
458  socklen_t *addrlen,
459  bool child_processes_inherit, Status &error) {
460  error.Clear();
461 #if defined(ANDROID_USE_ACCEPT_WORKAROUND)
462  // Hack:
463  // This enables static linking lldb-server to an API 21 libc, but still
464  // having it run on older devices. It is necessary because API 21 libc's
465  // implementation of accept() uses the accept4 syscall(), which is not
466  // available in older kernels. Using an older libc would fix this issue, but
467  // introduce other ones, as the old libraries were quite buggy.
468  int fd = syscall(__NR_accept, sockfd, addr, addrlen);
469  if (fd >= 0 && !child_processes_inherit) {
470  int flags = ::fcntl(fd, F_GETFD);
471  if (flags != -1 && ::fcntl(fd, F_SETFD, flags | FD_CLOEXEC) != -1)
472  return fd;
473  SetLastError(error);
474  close(fd);
475  }
476  return fd;
477 #elif defined(SOCK_CLOEXEC) && defined(HAVE_ACCEPT4)
478  int flags = 0;
479  if (!child_processes_inherit) {
480  flags |= SOCK_CLOEXEC;
481  }
482  NativeSocket fd = llvm::sys::RetryAfterSignal(-1, ::accept4,
483  sockfd, addr, addrlen, flags);
484 #else
485  NativeSocket fd = llvm::sys::RetryAfterSignal(-1, ::accept,
486  sockfd, addr, addrlen);
487 #endif
488  if (fd == kInvalidSocketValue)
489  SetLastError(error);
490  return fd;
491 }
int GetOption(int level, int option_name, int &option_value)
Definition: Socket.cpp:414
const void * set_socket_option_arg_type
Definition: Socket.cpp:59
Enumerations for broadcasting.
Definition: SBLaunchInfo.h:14
static const NativeSocket kInvalidSocketValue
Definition: Socket.h:49
static Status UnixDomainConnect(llvm::StringRef host_and_port, bool child_processes_inherit, Socket *&socket)
Definition: Socket.cpp:219
WaitableHandle GetWaitableHandle() override
Definition: Socket.cpp:328
llvm::Error Error
bool IsValid() const override
Definition: Socket.h:98
static Status UdpConnect(llvm::StringRef host_and_port, bool child_processes_inherit, Socket *&socket)
Definition: Socket.cpp:209
"lldb/Utility/RegularExpression.h" A C++ wrapper class for regex.
NativeSocket m_socket
Definition: Socket.h:120
static Status TcpConnect(llvm::StringRef host_and_port, bool child_processes_inherit, Socket *&socket)
Definition: Socket.cpp:149
static Status TcpListen(llvm::StringRef host_and_port, bool child_processes_inherit, Socket *&socket, Predicate< uint16_t > *predicate, int backlog=5)
Definition: Socket.cpp:169
Status Read(void *buf, size_t &num_bytes) override
Definition: Socket.cpp:333
void SetErrorToErrno()
Set the current error to errno.
Definition: Status.cpp:223
int SetOption(int level, int option_name, int option_value)
Definition: Socket.cpp:422
Standard Win32 error codes.
void * get_socket_option_arg_type
Definition: Socket.cpp:60
#define UINT32_MAX
Definition: lldb-defines.h:31
bool GetMatchAtIndex(llvm::StringRef s, uint32_t idx, std::string &match_str) const
static Status Connect(llvm::StringRef name, bool child_processes_inherit, Socket *&socket)
Definition: UDPSocket.cpp:56
void Clear()
Clear the object state.
Definition: Status.cpp:167
static Status UnixDomainAccept(llvm::StringRef host_and_port, bool child_processes_inherit, Socket *&socket)
Definition: Socket.cpp:235
void SetErrorString(llvm::StringRef err_str)
Set the current error string to err_str.
Definition: Status.cpp:241
static bool DecodeHostAndPort(llvm::StringRef host_and_port, std::string &host_str, std::string &port_str, int32_t &port, Status *error_ptr)
Definition: Socket.cpp:283
bool Success() const
Test for success condition.
Definition: Status.cpp:287
Always send a broadcast when the value is modified.
Definition: Predicate.h:28
static Status UnixAbstractAccept(llvm::StringRef host_and_port, bool child_processes_inherit, Socket *&socket)
Definition: Socket.cpp:266
~Socket() override
Definition: Socket.cpp:81
static Status UnixAbstractConnect(llvm::StringRef host_and_port, bool child_processes_inherit, Socket *&socket)
Definition: Socket.cpp:251
void SetValue(T value, PredicateBroadcastType broadcast_type)
Value set accessor.
Definition: Predicate.h:90
static void Terminate()
Definition: Socket.cpp:102
virtual size_t Send(const void *buf, const size_t num_bytes)
Definition: Socket.cpp:429
static void SetLastError(Status &error)
Definition: Socket.cpp:433
int NativeSocket
Definition: Socket.h:37
static NativeSocket AcceptSocket(NativeSocket sockfd, struct sockaddr *addr, socklen_t *addrlen, bool child_processes_inherit, Status &error)
Definition: Socket.cpp:457
Status Write(const void *buf, size_t &num_bytes) override
Definition: Socket.cpp:359
bool Fail() const
Test for error condition.
Definition: Status.cpp:181
bool Execute(llvm::StringRef string, Match *match=nullptr) const
Executes a regular expression.
int void SetError(ValueType err, lldb::ErrorType type)
Set accesssor with an error value and type.
Definition: Status.cpp:216
Log * GetLogIfAnyCategoriesSet(uint32_t mask)
Definition: Logging.cpp:61
Status Close() override
Definition: Socket.cpp:390
Definition: SBAddress.h:15
uint32_t ToUInt32(const char *s, uint32_t fail_value=0, int base=0, bool *success_ptr=nullptr)
#define LIBLLDB_LOG_CONNECTION
Definition: Logging.h:27
int SetErrorStringWithFormat(const char *format,...) __attribute__((format(printf
Set the current error string to a formatted error string.
Definition: Status.cpp:255
static std::unique_ptr< Socket > Create(const SocketProtocol protocol, bool child_processes_inherit, Status &error)
Definition: Socket.cpp:108
#define LIBLLDB_LOG_COMMUNICATION
Definition: Logging.h:26
static llvm::Error Initialize()
Definition: Socket.cpp:83
const char * AsCString(const char *default_error_str="unknown error") const
Get the error string associated with the current error.
Definition: Status.cpp:130
virtual Status PreDisconnect()
Definition: Socket.cpp:385
static NativeSocket CreateSocket(const int domain, const int type, const int protocol, bool child_processes_inherit, Status &error)
Definition: Socket.cpp:441
void Printf(const char *format,...) __attribute__((format(printf
Definition: Log.cpp:113
An error handling class.
Definition: Status.h:44