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"
13 #include "lldb/Host/SocketAddress.h"
14 #include "lldb/Host/StringConvert.h"
15 #include "lldb/Host/common/TCPSocket.h"
16 #include "lldb/Host/common/UDPSocket.h"
17 #include "lldb/Utility/Log.h"
18 #include "lldb/Utility/RegularExpression.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
26 #include "lldb/Host/posix/DomainSocket.h"
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__
38 #include "lldb/Host/linux/AbstractSocket.h"
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;
60 typedef void *get_socket_option_arg_type;
61 const NativeSocket Socket::kInvalidSocketValue = -1;
62 #endif // #if defined(_WIN32)
63
64 namespace {
65
IsInterrupted()66 bool IsInterrupted() {
67 #if defined(_WIN32)
68 return ::WSAGetLastError() == WSAEINTR;
69 #else
70 return errno == EINTR;
71 #endif
72 }
73 }
74
Socket(SocketProtocol protocol,bool should_close,bool child_processes_inherit)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
~Socket()82 Socket::~Socket() { Close(); }
83
Initialize()84 llvm::Error Socket::Initialize() {
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
Terminate()103 void Socket::Terminate() {
104 #if defined(_WIN32)
105 ::WSACleanup();
106 #endif
107 }
108
Create(const SocketProtocol protocol,bool child_processes_inherit,Status & error)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;
133 case ProtocolUnixAbstract:
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>>
TcpConnect(llvm::StringRef host_and_port,bool child_processes_inherit)151 Socket::TcpConnect(llvm::StringRef host_and_port,
152 bool child_processes_inherit) {
153 Log *log(lldb_private::GetLogIfAnyCategoriesSet(LIBLLDB_LOG_CONNECTION));
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>>
TcpListen(llvm::StringRef host_and_port,bool child_processes_inherit,Predicate<uint16_t> * predicate,int backlog)170 Socket::TcpListen(llvm::StringRef host_and_port, bool child_processes_inherit,
171 Predicate<uint16_t> *predicate, int backlog) {
172 Log *log(lldb_private::GetLogIfAnyCategoriesSet(LIBLLDB_LOG_CONNECTION));
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>>
UdpConnect(llvm::StringRef host_and_port,bool child_processes_inherit)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
UnixDomainConnect(llvm::StringRef name,bool child_processes_inherit,Socket * & socket)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
UnixDomainAccept(llvm::StringRef name,bool child_processes_inherit,Socket * & socket)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
UnixAbstractConnect(llvm::StringRef name,bool child_processes_inherit,Socket * & socket)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
UnixAbstractAccept(llvm::StringRef name,bool child_processes_inherit,Socket * & socket)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
DecodeHostAndPort(llvm::StringRef host_and_port,std::string & host_str,std::string & port_str,int32_t & port,Status * error_ptr)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
GetWaitableHandle()318 IOObject::WaitableHandle Socket::GetWaitableHandle() {
319 // TODO: On Windows, use WSAEventSelect
320 return m_socket;
321 }
322
Read(void * buf,size_t & num_bytes)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
336 Log *log(lldb_private::GetLogIfAnyCategoriesSet(LIBLLDB_LOG_COMMUNICATION));
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
Write(const void * buf,size_t & num_bytes)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
364 Log *log(lldb_private::GetLogIfAnyCategoriesSet(LIBLLDB_LOG_COMMUNICATION));
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
PreDisconnect()378 Status Socket::PreDisconnect() {
379 Status error;
380 return error;
381 }
382
Close()383 Status Socket::Close() {
384 Status error;
385 if (!IsValid() || !m_should_close_fd)
386 return error;
387
388 Log *log(lldb_private::GetLogIfAnyCategoriesSet(LIBLLDB_LOG_CONNECTION));
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
398 m_socket = kInvalidSocketValue;
399 if (!success) {
400 SetLastError(error);
401 }
402
403 return error;
404 }
405
GetOption(int level,int option_name,int & option_value)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
SetOption(int level,int option_name,int option_value)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
Send(const void * buf,const size_t num_bytes)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
SetLastError(Status & error)425 void Socket::SetLastError(Status &error) {
426 #if defined(_WIN32)
427 error.SetError(::WSAGetLastError(), lldb::eErrorTypeWin32);
428 #else
429 error.SetErrorToErrno();
430 #endif
431 }
432
CreateSocket(const int domain,const int type,const int protocol,bool child_processes_inherit,Status & error)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
AcceptSocket(NativeSocket sockfd,struct sockaddr * addr,socklen_t * addrlen,bool child_processes_inherit,Status & error)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 }
484