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Socket.cpp
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1 //===-- Socket.cpp --------------------------------------------------------===//
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 #if LLDB_ENABLE_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), m_protocol(protocol),
78  m_socket(kInvalidSocketValue),
79  m_child_processes_inherit(child_processes_inherit),
80  m_should_close_fd(should_close) {}
81 
83 
85 #if defined(_WIN32)
86  auto wVersion = WINSOCK_VERSION;
87  WSADATA wsaData;
88  int err = ::WSAStartup(wVersion, &wsaData);
89  if (err == 0) {
90  if (wsaData.wVersion < wVersion) {
91  WSACleanup();
92  return llvm::make_error<llvm::StringError>(
93  "WSASock version is not expected.", llvm::inconvertibleErrorCode());
94  }
95  } else {
96  return llvm::errorCodeToError(llvm::mapWindowsError(::WSAGetLastError()));
97  }
98 #endif
99 
100  return llvm::Error::success();
101 }
102 
104 #if defined(_WIN32)
105  ::WSACleanup();
106 #endif
107 }
108 
109 std::unique_ptr<Socket> Socket::Create(const SocketProtocol protocol,
110  bool child_processes_inherit,
111  Status &error) {
112  error.Clear();
113 
114  std::unique_ptr<Socket> socket_up;
115  switch (protocol) {
116  case ProtocolTcp:
117  socket_up =
118  std::make_unique<TCPSocket>(true, child_processes_inherit);
119  break;
120  case ProtocolUdp:
121  socket_up =
122  std::make_unique<UDPSocket>(true, child_processes_inherit);
123  break;
124  case ProtocolUnixDomain:
125 #if LLDB_ENABLE_POSIX
126  socket_up =
127  std::make_unique<DomainSocket>(true, child_processes_inherit);
128 #else
129  error.SetErrorString(
130  "Unix domain sockets are not supported on this platform.");
131 #endif
132  break;
134 #ifdef __linux__
135  socket_up =
136  std::make_unique<AbstractSocket>(child_processes_inherit);
137 #else
138  error.SetErrorString(
139  "Abstract domain sockets are not supported on this platform.");
140 #endif
141  break;
142  }
143 
144  if (error.Fail())
145  socket_up.reset();
146 
147  return socket_up;
148 }
149 
150 llvm::Expected<std::unique_ptr<Socket>>
151 Socket::TcpConnect(llvm::StringRef host_and_port,
152  bool child_processes_inherit) {
154  LLDB_LOG(log, "host_and_port = {0}", host_and_port);
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.ToError();
161 
162  error = connect_socket->Connect(host_and_port);
163  if (error.Success())
164  return std::move(connect_socket);
165 
166  return error.ToError();
167 }
168 
169 llvm::Expected<std::unique_ptr<TCPSocket>>
170 Socket::TcpListen(llvm::StringRef host_and_port, bool child_processes_inherit,
171  Predicate<uint16_t> *predicate, int backlog) {
173  LLDB_LOG(log, "host_and_port = {0}", host_and_port);
174 
175  Status error;
176  std::string host_str;
177  std::string port_str;
178  int32_t port = INT32_MIN;
179  if (!DecodeHostAndPort(host_and_port, host_str, port_str, port, &error))
180  return error.ToError();
181 
182  std::unique_ptr<TCPSocket> listen_socket(
183  new TCPSocket(true, child_processes_inherit));
184 
185  error = listen_socket->Listen(host_and_port, backlog);
186  if (error.Fail())
187  return error.ToError();
188 
189  // We were asked to listen on port zero which means we must now read the
190  // actual port that was given to us as port zero is a special code for
191  // "find an open port for me".
192  if (port == 0)
193  port = listen_socket->GetLocalPortNumber();
194 
195  // Set the port predicate since when doing a listen://<host>:<port> it
196  // often needs to accept the incoming connection which is a blocking system
197  // call. Allowing access to the bound port using a predicate allows us to
198  // wait for the port predicate to be set to a non-zero value from another
199  // thread in an efficient manor.
200  if (predicate)
201  predicate->SetValue(port, eBroadcastAlways);
202  return std::move(listen_socket);
203 }
204 
205 llvm::Expected<std::unique_ptr<UDPSocket>>
206 Socket::UdpConnect(llvm::StringRef host_and_port,
207  bool child_processes_inherit) {
208  return UDPSocket::Connect(host_and_port, child_processes_inherit);
209 }
210 
211 Status Socket::UnixDomainConnect(llvm::StringRef name,
212  bool child_processes_inherit,
213  Socket *&socket) {
214  Status error;
215  std::unique_ptr<Socket> connect_socket(
216  Create(ProtocolUnixDomain, child_processes_inherit, error));
217  if (error.Fail())
218  return error;
219 
220  error = connect_socket->Connect(name);
221  if (error.Success())
222  socket = connect_socket.release();
223 
224  return error;
225 }
226 
227 Status Socket::UnixDomainAccept(llvm::StringRef name,
228  bool child_processes_inherit, Socket *&socket) {
229  Status error;
230  std::unique_ptr<Socket> listen_socket(
231  Create(ProtocolUnixDomain, child_processes_inherit, error));
232  if (error.Fail())
233  return error;
234 
235  error = listen_socket->Listen(name, 5);
236  if (error.Fail())
237  return error;
238 
239  error = listen_socket->Accept(socket);
240  return error;
241 }
242 
243 Status Socket::UnixAbstractConnect(llvm::StringRef name,
244  bool child_processes_inherit,
245  Socket *&socket) {
246  Status error;
247  std::unique_ptr<Socket> connect_socket(
248  Create(ProtocolUnixAbstract, child_processes_inherit, error));
249  if (error.Fail())
250  return error;
251 
252  error = connect_socket->Connect(name);
253  if (error.Success())
254  socket = connect_socket.release();
255  return error;
256 }
257 
258 Status Socket::UnixAbstractAccept(llvm::StringRef name,
259  bool child_processes_inherit,
260  Socket *&socket) {
261  Status error;
262  std::unique_ptr<Socket> listen_socket(
263  Create(ProtocolUnixAbstract, child_processes_inherit, error));
264  if (error.Fail())
265  return error;
266 
267  error = listen_socket->Listen(name, 5);
268  if (error.Fail())
269  return error;
270 
271  error = listen_socket->Accept(socket);
272  return error;
273 }
274 
275 bool Socket::DecodeHostAndPort(llvm::StringRef host_and_port,
276  std::string &host_str, std::string &port_str,
277  int32_t &port, Status *error_ptr) {
278  static RegularExpression g_regex(
279  llvm::StringRef("([^:]+|\\[[0-9a-fA-F:]+.*\\]):([0-9]+)"));
280  llvm::SmallVector<llvm::StringRef, 3> matches;
281  if (g_regex.Execute(host_and_port, &matches)) {
282  host_str = matches[1].str();
283  port_str = matches[2].str();
284  // IPv6 addresses are wrapped in [] when specified with ports
285  if (host_str.front() == '[' && host_str.back() == ']')
286  host_str = host_str.substr(1, host_str.size() - 2);
287  bool ok = false;
288  port = StringConvert::ToUInt32(port_str.c_str(), UINT32_MAX, 10, &ok);
289  if (ok && port <= UINT16_MAX) {
290  if (error_ptr)
291  error_ptr->Clear();
292  return true;
293  }
294  // port is too large
295  if (error_ptr)
296  error_ptr->SetErrorStringWithFormat(
297  "invalid host:port specification: '%s'", host_and_port.str().c_str());
298  return false;
299  }
300 
301  // If this was unsuccessful, then check if it's simply a signed 32-bit
302  // integer, representing a port with an empty host.
303  host_str.clear();
304  port_str.clear();
305  if (to_integer(host_and_port, port, 10) && port < UINT16_MAX) {
306  port_str = std::string(host_and_port);
307  if (error_ptr)
308  error_ptr->Clear();
309  return true;
310  }
311 
312  if (error_ptr)
313  error_ptr->SetErrorStringWithFormat("invalid host:port specification: '%s'",
314  host_and_port.str().c_str());
315  return false;
316 }
317 
319  // TODO: On Windows, use WSAEventSelect
320  return m_socket;
321 }
322 
323 Status Socket::Read(void *buf, size_t &num_bytes) {
324  Status error;
325  int bytes_received = 0;
326  do {
327  bytes_received = ::recv(m_socket, static_cast<char *>(buf), num_bytes, 0);
328  } while (bytes_received < 0 && IsInterrupted());
329 
330  if (bytes_received < 0) {
331  SetLastError(error);
332  num_bytes = 0;
333  } else
334  num_bytes = bytes_received;
335 
337  if (log) {
338  LLDB_LOGF(log,
339  "%p Socket::Read() (socket = %" PRIu64
340  ", src = %p, src_len = %" PRIu64 ", flags = 0) => %" PRIi64
341  " (error = %s)",
342  static_cast<void *>(this), static_cast<uint64_t>(m_socket), buf,
343  static_cast<uint64_t>(num_bytes),
344  static_cast<int64_t>(bytes_received), error.AsCString());
345  }
346 
347  return error;
348 }
349 
350 Status Socket::Write(const void *buf, size_t &num_bytes) {
351  const size_t src_len = num_bytes;
352  Status error;
353  int bytes_sent = 0;
354  do {
355  bytes_sent = Send(buf, num_bytes);
356  } while (bytes_sent < 0 && IsInterrupted());
357 
358  if (bytes_sent < 0) {
359  SetLastError(error);
360  num_bytes = 0;
361  } else
362  num_bytes = bytes_sent;
363 
365  if (log) {
366  LLDB_LOGF(log,
367  "%p Socket::Write() (socket = %" PRIu64
368  ", src = %p, src_len = %" PRIu64 ", flags = 0) => %" PRIi64
369  " (error = %s)",
370  static_cast<void *>(this), static_cast<uint64_t>(m_socket), buf,
371  static_cast<uint64_t>(src_len),
372  static_cast<int64_t>(bytes_sent), error.AsCString());
373  }
374 
375  return error;
376 }
377 
379  Status error;
380  return error;
381 }
382 
384  Status error;
385  if (!IsValid() || !m_should_close_fd)
386  return error;
387 
389  LLDB_LOGF(log, "%p Socket::Close (fd = %" PRIu64 ")",
390  static_cast<void *>(this), static_cast<uint64_t>(m_socket));
391 
392 #if defined(_WIN32)
393  bool success = !!closesocket(m_socket);
394 #else
395  bool success = !!::close(m_socket);
396 #endif
397  // A reference to a FD was passed in, set it to an invalid value
399  if (!success) {
400  SetLastError(error);
401  }
402 
403  return error;
404 }
405 
406 int Socket::GetOption(int level, int option_name, int &option_value) {
407  get_socket_option_arg_type option_value_p =
408  reinterpret_cast<get_socket_option_arg_type>(&option_value);
409  socklen_t option_value_size = sizeof(int);
410  return ::getsockopt(m_socket, level, option_name, option_value_p,
411  &option_value_size);
412 }
413 
414 int Socket::SetOption(int level, int option_name, int option_value) {
415  set_socket_option_arg_type option_value_p =
416  reinterpret_cast<get_socket_option_arg_type>(&option_value);
417  return ::setsockopt(m_socket, level, option_name, option_value_p,
418  sizeof(option_value));
419 }
420 
421 size_t Socket::Send(const void *buf, const size_t num_bytes) {
422  return ::send(m_socket, static_cast<const char *>(buf), num_bytes, 0);
423 }
424 
426 #if defined(_WIN32)
427  error.SetError(::WSAGetLastError(), lldb::eErrorTypeWin32);
428 #else
429  error.SetErrorToErrno();
430 #endif
431 }
432 
433 NativeSocket Socket::CreateSocket(const int domain, const int type,
434  const int protocol,
435  bool child_processes_inherit, Status &error) {
436  error.Clear();
437  auto socket_type = type;
438 #ifdef SOCK_CLOEXEC
439  if (!child_processes_inherit)
440  socket_type |= SOCK_CLOEXEC;
441 #endif
442  auto sock = ::socket(domain, socket_type, protocol);
443  if (sock == kInvalidSocketValue)
444  SetLastError(error);
445 
446  return sock;
447 }
448 
449 NativeSocket Socket::AcceptSocket(NativeSocket sockfd, struct sockaddr *addr,
450  socklen_t *addrlen,
451  bool child_processes_inherit, Status &error) {
452  error.Clear();
453 #if defined(ANDROID_USE_ACCEPT_WORKAROUND)
454  // Hack:
455  // This enables static linking lldb-server to an API 21 libc, but still
456  // having it run on older devices. It is necessary because API 21 libc's
457  // implementation of accept() uses the accept4 syscall(), which is not
458  // available in older kernels. Using an older libc would fix this issue, but
459  // introduce other ones, as the old libraries were quite buggy.
460  int fd = syscall(__NR_accept, sockfd, addr, addrlen);
461  if (fd >= 0 && !child_processes_inherit) {
462  int flags = ::fcntl(fd, F_GETFD);
463  if (flags != -1 && ::fcntl(fd, F_SETFD, flags | FD_CLOEXEC) != -1)
464  return fd;
465  SetLastError(error);
466  close(fd);
467  }
468  return fd;
469 #elif defined(SOCK_CLOEXEC) && defined(HAVE_ACCEPT4)
470  int flags = 0;
471  if (!child_processes_inherit) {
472  flags |= SOCK_CLOEXEC;
473  }
474  NativeSocket fd = llvm::sys::RetryAfterSignal(
475  static_cast<NativeSocket>(-1), ::accept4, sockfd, addr, addrlen, flags);
476 #else
477  NativeSocket fd = llvm::sys::RetryAfterSignal(
478  static_cast<NativeSocket>(-1), ::accept, sockfd, addr, addrlen);
479 #endif
480  if (fd == kInvalidSocketValue)
481  SetLastError(error);
482  return fd;
483 }
int GetOption(int level, int option_name, int &option_value)
Definition: Socket.cpp:406
const void * set_socket_option_arg_type
Definition: Socket.cpp:59
llvm::Error ToError() const
Definition: Status.cpp:90
A class that represents a running process on the host machine.
static const NativeSocket kInvalidSocketValue
Definition: Socket.h:51
static Status UnixDomainConnect(llvm::StringRef host_and_port, bool child_processes_inherit, Socket *&socket)
Definition: Socket.cpp:211
WaitableHandle GetWaitableHandle() override
Definition: Socket.cpp:318
static llvm::Expected< std::unique_ptr< Socket > > TcpConnect(llvm::StringRef host_and_port, bool child_processes_inherit)
Definition: Socket.cpp:151
llvm::Error Error
bool IsValid() const override
Definition: Socket.h:103
static llvm::Expected< std::unique_ptr< TCPSocket > > TcpListen(llvm::StringRef host_and_port, bool child_processes_inherit, Predicate< uint16_t > *predicate, int backlog=5)
Definition: Socket.cpp:170
NativeSocket m_socket
Definition: Socket.h:128
#define LLDB_LOG(log,...)
The LLDB_LOG* macros defined below are the way to emit log messages.
Definition: Log.h:242
bool m_should_close_fd
Definition: Socket.h:130
Status Read(void *buf, size_t &num_bytes) override
Definition: Socket.cpp:323
void SetErrorToErrno()
Set the current error to errno.
Definition: Status.cpp:224
int SetOption(int level, int option_name, int option_value)
Definition: Socket.cpp:414
Standard Win32 error codes.
void * get_socket_option_arg_type
Definition: Socket.cpp:60
#define UINT32_MAX
Definition: lldb-defines.h:31
static llvm::raw_ostream & error(Stream &strm)
void Clear()
Clear the object state.
Definition: Status.cpp:168
static Status UnixDomainAccept(llvm::StringRef host_and_port, bool child_processes_inherit, Socket *&socket)
Definition: Socket.cpp:227
void SetErrorString(llvm::StringRef err_str)
Set the current error string to err_str.
Definition: Status.cpp:242
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:275
bool Success() const
Test for success condition.
Definition: Status.cpp:288
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:258
~Socket() override
Definition: Socket.cpp:82
static Status UnixAbstractConnect(llvm::StringRef host_and_port, bool child_processes_inherit, Socket *&socket)
Definition: Socket.cpp:243
void SetValue(T value, PredicateBroadcastType broadcast_type)
Value set accessor.
Definition: Predicate.h:90
static void Terminate()
Definition: Socket.cpp:103
virtual size_t Send(const void *buf, const size_t num_bytes)
Definition: Socket.cpp:421
#define LLDB_LOGF(log,...)
Definition: Log.h:249
static void SetLastError(Status &error)
Definition: Socket.cpp:425
static llvm::Expected< std::unique_ptr< UDPSocket > > UdpConnect(llvm::StringRef host_and_port, bool child_processes_inherit)
Definition: Socket.cpp:206
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:449
Status Write(const void *buf, size_t &num_bytes) override
Definition: Socket.cpp:350
bool Fail() const
Test for error condition.
Definition: Status.cpp:182
int void SetError(ValueType err, lldb::ErrorType type)
Set accessor with an error value and type.
Definition: Status.cpp:217
Log * GetLogIfAnyCategoriesSet(uint32_t mask)
Definition: Logging.cpp:62
Status Close() override
Definition: Socket.cpp:383
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:256
static std::unique_ptr< Socket > Create(const SocketProtocol protocol, bool child_processes_inherit, Status &error)
Definition: Socket.cpp:109
#define LIBLLDB_LOG_COMMUNICATION
Definition: Logging.h:26
static llvm::Error Initialize()
Definition: Socket.cpp:84
const char * AsCString(const char *default_error_str="unknown error") const
Get the error string associated with the current error.
Definition: Status.cpp:131
bool Execute(llvm::StringRef string, llvm::SmallVectorImpl< llvm::StringRef > *matches=nullptr) const
Execute a regular expression match using the compiled regular expression that is already in this obje...
virtual Status PreDisconnect()
Definition: Socket.cpp:378
static NativeSocket CreateSocket(const int domain, const int type, const int protocol, bool child_processes_inherit, Status &error)
Definition: Socket.cpp:433
static llvm::Expected< std::unique_ptr< UDPSocket > > Connect(llvm::StringRef name, bool child_processes_inherit)
Definition: UDPSocket.cpp:57
An error handling class.
Definition: Status.h:44