1 //===-- Socket.cpp ----------------------------------------------*- C++ -*-===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 
10 #include "lldb/Host/Socket.h"
11 
12 #include "lldb/Core/Log.h"
13 #include "lldb/Core/RegularExpression.h"
14 #include "lldb/Host/Config.h"
15 #include "lldb/Host/Host.h"
16 #include "lldb/Host/SocketAddress.h"
17 #include "lldb/Host/StringConvert.h"
18 #include "lldb/Host/common/TCPSocket.h"
19 #include "lldb/Host/common/UDPSocket.h"
20 
21 #ifndef LLDB_DISABLE_POSIX
22 #include "lldb/Host/posix/DomainSocket.h"
23 
24 #include <arpa/inet.h>
25 #include <netdb.h>
26 #include <netinet/in.h>
27 #include <netinet/tcp.h>
28 #include <sys/socket.h>
29 #include <sys/un.h>
30 #endif
31 
32 #ifdef __linux__
33 #include "lldb/Host/linux/AbstractSocket.h"
34 #endif
35 
36 #ifdef __ANDROID__
37 #include <arpa/inet.h>
38 #include <asm-generic/errno-base.h>
39 #include <errno.h>
40 #include <linux/tcp.h>
41 #if defined(ANDROID_ARM_BUILD_STATIC) || defined(ANDROID_MIPS_BUILD_STATIC)
42 #include <fcntl.h>
43 #include <sys/syscall.h>
44 #include <unistd.h>
45 #endif // ANDROID_ARM_BUILD_STATIC || ANDROID_MIPS_BUILD_STATIC
46 #endif // __ANDROID__
47 
48 using namespace lldb;
49 using namespace lldb_private;
50 
51 #if defined(_WIN32)
52 typedef const char *set_socket_option_arg_type;
53 typedef char *get_socket_option_arg_type;
54 const NativeSocket Socket::kInvalidSocketValue = INVALID_SOCKET;
55 #else  // #if defined(_WIN32)
56 typedef const void *set_socket_option_arg_type;
57 typedef void *get_socket_option_arg_type;
58 const NativeSocket Socket::kInvalidSocketValue = -1;
59 #endif // #if defined(_WIN32)
60 
61 namespace {
62 
63 bool IsInterrupted() {
64 #if defined(_WIN32)
65   return ::WSAGetLastError() == WSAEINTR;
66 #else
67   return errno == EINTR;
68 #endif
69 }
70 }
71 
72 Socket::Socket(NativeSocket socket, SocketProtocol protocol, bool should_close)
73     : IOObject(eFDTypeSocket, should_close), m_protocol(protocol),
74       m_socket(socket) {}
75 
76 Socket::~Socket() { Close(); }
77 
78 std::unique_ptr<Socket> Socket::Create(const SocketProtocol protocol,
79                                        bool child_processes_inherit,
80                                        Error &error) {
81   error.Clear();
82 
83   std::unique_ptr<Socket> socket_up;
84   switch (protocol) {
85   case ProtocolTcp:
86     socket_up.reset(new TCPSocket(child_processes_inherit, error));
87     break;
88   case ProtocolUdp:
89     socket_up.reset(new UDPSocket(child_processes_inherit, error));
90     break;
91   case ProtocolUnixDomain:
92 #ifndef LLDB_DISABLE_POSIX
93     socket_up.reset(new DomainSocket(child_processes_inherit, error));
94 #else
95     error.SetErrorString(
96         "Unix domain sockets are not supported on this platform.");
97 #endif
98     break;
99   case ProtocolUnixAbstract:
100 #ifdef __linux__
101     socket_up.reset(new AbstractSocket(child_processes_inherit, error));
102 #else
103     error.SetErrorString(
104         "Abstract domain sockets are not supported on this platform.");
105 #endif
106     break;
107   }
108 
109   if (error.Fail())
110     socket_up.reset();
111 
112   return socket_up;
113 }
114 
115 Error Socket::TcpConnect(llvm::StringRef host_and_port,
116                          bool child_processes_inherit, Socket *&socket) {
117   Log *log(lldb_private::GetLogIfAnyCategoriesSet(LIBLLDB_LOG_COMMUNICATION));
118   if (log)
119     log->Printf("Socket::%s (host/port = %s)", __FUNCTION__,
120                 host_and_port.data());
121 
122   Error error;
123   std::unique_ptr<Socket> connect_socket(
124       Create(ProtocolTcp, child_processes_inherit, error));
125   if (error.Fail())
126     return error;
127 
128   error = connect_socket->Connect(host_and_port);
129   if (error.Success())
130     socket = connect_socket.release();
131 
132   return error;
133 }
134 
135 Error Socket::TcpListen(llvm::StringRef host_and_port,
136                         bool child_processes_inherit, Socket *&socket,
137                         Predicate<uint16_t> *predicate, int backlog) {
138   Log *log(lldb_private::GetLogIfAnyCategoriesSet(LIBLLDB_LOG_CONNECTION));
139   if (log)
140     log->Printf("Socket::%s (%s)", __FUNCTION__, host_and_port.data());
141 
142   Error error;
143   std::string host_str;
144   std::string port_str;
145   int32_t port = INT32_MIN;
146   if (!DecodeHostAndPort(host_and_port, host_str, port_str, port, &error))
147     return error;
148 
149   std::unique_ptr<TCPSocket> listen_socket(
150       new TCPSocket(child_processes_inherit, error));
151   if (error.Fail())
152     return error;
153 
154   error = listen_socket->Listen(host_and_port, backlog);
155   if (error.Success()) {
156     // We were asked to listen on port zero which means we
157     // must now read the actual port that was given to us
158     // as port zero is a special code for "find an open port
159     // for me".
160     if (port == 0)
161       port = listen_socket->GetLocalPortNumber();
162 
163     // Set the port predicate since when doing a listen://<host>:<port>
164     // it often needs to accept the incoming connection which is a blocking
165     // system call. Allowing access to the bound port using a predicate allows
166     // us to wait for the port predicate to be set to a non-zero value from
167     // another thread in an efficient manor.
168     if (predicate)
169       predicate->SetValue(port, eBroadcastAlways);
170     socket = listen_socket.release();
171   }
172 
173   return error;
174 }
175 
176 Error Socket::UdpConnect(llvm::StringRef host_and_port,
177                          bool child_processes_inherit, Socket *&send_socket,
178                          Socket *&recv_socket) {
179   Log *log(lldb_private::GetLogIfAnyCategoriesSet(LIBLLDB_LOG_CONNECTION));
180   if (log)
181     log->Printf("Socket::%s (host/port = %s)", __FUNCTION__,
182                 host_and_port.data());
183 
184   return UDPSocket::Connect(host_and_port, child_processes_inherit, send_socket,
185                             recv_socket);
186 }
187 
188 Error Socket::UnixDomainConnect(llvm::StringRef name,
189                                 bool child_processes_inherit, Socket *&socket) {
190   Error error;
191   std::unique_ptr<Socket> connect_socket(
192       Create(ProtocolUnixDomain, child_processes_inherit, error));
193   if (error.Fail())
194     return error;
195 
196   error = connect_socket->Connect(name);
197   if (error.Success())
198     socket = connect_socket.release();
199 
200   return error;
201 }
202 
203 Error Socket::UnixDomainAccept(llvm::StringRef name,
204                                bool child_processes_inherit, Socket *&socket) {
205   Error error;
206   std::unique_ptr<Socket> listen_socket(
207       Create(ProtocolUnixDomain, child_processes_inherit, error));
208   if (error.Fail())
209     return error;
210 
211   error = listen_socket->Listen(name, 5);
212   if (error.Fail())
213     return error;
214 
215   error = listen_socket->Accept(name, child_processes_inherit, socket);
216   return error;
217 }
218 
219 Error Socket::UnixAbstractConnect(llvm::StringRef name,
220                                   bool child_processes_inherit,
221                                   Socket *&socket) {
222   Error error;
223   std::unique_ptr<Socket> connect_socket(
224       Create(ProtocolUnixAbstract, 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   return error;
232 }
233 
234 Error Socket::UnixAbstractAccept(llvm::StringRef name,
235                                  bool child_processes_inherit,
236                                  Socket *&socket) {
237   Error error;
238   std::unique_ptr<Socket> listen_socket(
239       Create(ProtocolUnixAbstract, 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(name, child_processes_inherit, socket);
248   return error;
249 }
250 
251 bool Socket::DecodeHostAndPort(llvm::StringRef host_and_port,
252                                std::string &host_str, std::string &port_str,
253                                int32_t &port, Error *error_ptr) {
254   static RegularExpression g_regex(llvm::StringRef("([^:]+):([0-9]+)"));
255   RegularExpression::Match regex_match(2);
256   if (g_regex.Execute(host_and_port, &regex_match)) {
257     if (regex_match.GetMatchAtIndex(host_and_port.data(), 1, host_str) &&
258         regex_match.GetMatchAtIndex(host_and_port.data(), 2, port_str)) {
259       bool ok = false;
260       port = StringConvert::ToUInt32(port_str.c_str(), UINT32_MAX, 10, &ok);
261       if (ok && port <= UINT16_MAX) {
262         if (error_ptr)
263           error_ptr->Clear();
264         return true;
265       }
266       // port is too large
267       if (error_ptr)
268         error_ptr->SetErrorStringWithFormat(
269             "invalid host:port specification: '%s'", host_and_port.data());
270       return false;
271     }
272   }
273 
274   // If this was unsuccessful, then check if it's simply a signed 32-bit
275   // integer, representing
276   // a port with an empty host.
277   host_str.clear();
278   port_str.clear();
279   bool ok = false;
280   port = StringConvert::ToUInt32(host_and_port.data(), UINT32_MAX, 10, &ok);
281   if (ok && port < UINT16_MAX) {
282     port_str = host_and_port;
283     if (error_ptr)
284       error_ptr->Clear();
285     return true;
286   }
287 
288   if (error_ptr)
289     error_ptr->SetErrorStringWithFormat("invalid host:port specification: '%s'",
290                                         host_and_port.data());
291   return false;
292 }
293 
294 IOObject::WaitableHandle Socket::GetWaitableHandle() {
295   // TODO: On Windows, use WSAEventSelect
296   return m_socket;
297 }
298 
299 Error Socket::Read(void *buf, size_t &num_bytes) {
300   Error error;
301   int bytes_received = 0;
302   do {
303     bytes_received = ::recv(m_socket, static_cast<char *>(buf), num_bytes, 0);
304   } while (bytes_received < 0 && IsInterrupted());
305 
306   if (bytes_received < 0) {
307     SetLastError(error);
308     num_bytes = 0;
309   } else
310     num_bytes = bytes_received;
311 
312   Log *log(lldb_private::GetLogIfAnyCategoriesSet(LIBLLDB_LOG_COMMUNICATION));
313   if (log) {
314     log->Printf("%p Socket::Read() (socket = %" PRIu64
315                 ", src = %p, src_len = %" PRIu64 ", flags = 0) => %" PRIi64
316                 " (error = %s)",
317                 static_cast<void *>(this), static_cast<uint64_t>(m_socket), buf,
318                 static_cast<uint64_t>(num_bytes),
319                 static_cast<int64_t>(bytes_received), error.AsCString());
320   }
321 
322   return error;
323 }
324 
325 Error Socket::Write(const void *buf, size_t &num_bytes) {
326   Error error;
327   int bytes_sent = 0;
328   do {
329     bytes_sent = Send(buf, num_bytes);
330   } while (bytes_sent < 0 && IsInterrupted());
331 
332   if (bytes_sent < 0) {
333     SetLastError(error);
334     num_bytes = 0;
335   } else
336     num_bytes = bytes_sent;
337 
338   Log *log(lldb_private::GetLogIfAnyCategoriesSet(LIBLLDB_LOG_COMMUNICATION));
339   if (log) {
340     log->Printf("%p Socket::Write() (socket = %" PRIu64
341                 ", src = %p, src_len = %" PRIu64 ", flags = 0) => %" PRIi64
342                 " (error = %s)",
343                 static_cast<void *>(this), static_cast<uint64_t>(m_socket), buf,
344                 static_cast<uint64_t>(num_bytes),
345                 static_cast<int64_t>(bytes_sent), error.AsCString());
346   }
347 
348   return error;
349 }
350 
351 Error Socket::PreDisconnect() {
352   Error error;
353   return error;
354 }
355 
356 Error Socket::Close() {
357   Error error;
358   if (!IsValid() || !m_should_close_fd)
359     return error;
360 
361   Log *log(lldb_private::GetLogIfAnyCategoriesSet(LIBLLDB_LOG_CONNECTION));
362   if (log)
363     log->Printf("%p Socket::Close (fd = %i)", static_cast<void *>(this),
364                 m_socket);
365 
366 #if defined(_WIN32)
367   bool success = !!closesocket(m_socket);
368 #else
369   bool success = !!::close(m_socket);
370 #endif
371   // A reference to a FD was passed in, set it to an invalid value
372   m_socket = kInvalidSocketValue;
373   if (!success) {
374     SetLastError(error);
375   }
376 
377   return error;
378 }
379 
380 int Socket::GetOption(int level, int option_name, int &option_value) {
381   get_socket_option_arg_type option_value_p =
382       reinterpret_cast<get_socket_option_arg_type>(&option_value);
383   socklen_t option_value_size = sizeof(int);
384   return ::getsockopt(m_socket, level, option_name, option_value_p,
385                       &option_value_size);
386 }
387 
388 int Socket::SetOption(int level, int option_name, int option_value) {
389   set_socket_option_arg_type option_value_p =
390       reinterpret_cast<get_socket_option_arg_type>(&option_value);
391   return ::setsockopt(m_socket, level, option_name, option_value_p,
392                       sizeof(option_value));
393 }
394 
395 size_t Socket::Send(const void *buf, const size_t num_bytes) {
396   return ::send(m_socket, static_cast<const char *>(buf), num_bytes, 0);
397 }
398 
399 void Socket::SetLastError(Error &error) {
400 #if defined(_WIN32)
401   error.SetError(::WSAGetLastError(), lldb::eErrorTypeWin32);
402 #else
403   error.SetErrorToErrno();
404 #endif
405 }
406 
407 NativeSocket Socket::CreateSocket(const int domain, const int type,
408                                   const int protocol,
409                                   bool child_processes_inherit, Error &error) {
410   error.Clear();
411   auto socketType = type;
412 #ifdef SOCK_CLOEXEC
413   if (!child_processes_inherit)
414     socketType |= SOCK_CLOEXEC;
415 #endif
416   auto sock = ::socket(domain, socketType, protocol);
417   if (sock == kInvalidSocketValue)
418     SetLastError(error);
419 
420   return sock;
421 }
422 
423 NativeSocket Socket::AcceptSocket(NativeSocket sockfd, struct sockaddr *addr,
424                                   socklen_t *addrlen,
425                                   bool child_processes_inherit, Error &error) {
426   error.Clear();
427 #if defined(ANDROID_ARM_BUILD_STATIC) || defined(ANDROID_MIPS_BUILD_STATIC)
428   // Temporary workaround for statically linking Android lldb-server with the
429   // latest API.
430   int fd = syscall(__NR_accept, sockfd, addr, addrlen);
431   if (fd >= 0 && !child_processes_inherit) {
432     int flags = ::fcntl(fd, F_GETFD);
433     if (flags != -1 && ::fcntl(fd, F_SETFD, flags | FD_CLOEXEC) != -1)
434       return fd;
435     SetLastError(error);
436     close(fd);
437   }
438   return fd;
439 #elif defined(SOCK_CLOEXEC)
440   int flags = 0;
441   if (!child_processes_inherit) {
442     flags |= SOCK_CLOEXEC;
443   }
444 #if defined(__NetBSD__)
445   NativeSocket fd = ::paccept(sockfd, addr, addrlen, nullptr, flags);
446 #else
447   NativeSocket fd = ::accept4(sockfd, addr, addrlen, flags);
448 #endif
449 #else
450   NativeSocket fd = ::accept(sockfd, addr, addrlen);
451 #endif
452   if (fd == kInvalidSocketValue)
453     SetLastError(error);
454   return fd;
455 }
456