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/TimeValue.h"
19 #include "lldb/Host/common/TCPSocket.h"
20 #include "lldb/Host/common/UDPSocket.h"
21 
22 #ifndef LLDB_DISABLE_POSIX
23 #include "lldb/Host/posix/DomainSocket.h"
24 
25 #include <arpa/inet.h>
26 #include <netdb.h>
27 #include <netinet/in.h>
28 #include <netinet/tcp.h>
29 #include <sys/socket.h>
30 #include <sys/un.h>
31 #endif
32 
33 #ifdef __linux__
34 #include "lldb/Host/linux/AbstractSocket.h"
35 #endif
36 
37 #ifdef __ANDROID_NDK__
38 #include <arpa/inet.h>
39 #include <asm-generic/errno-base.h>
40 #include <bits/error_constants.h>
41 #include <errno.h>
42 #include <linux/tcp.h>
43 #if defined(ANDROID_ARM_BUILD_STATIC) || defined(ANDROID_MIPS_BUILD_STATIC)
44 #include <fcntl.h>
45 #include <sys/syscall.h>
46 #include <unistd.h>
47 #endif // ANDROID_ARM_BUILD_STATIC || ANDROID_MIPS_BUILD_STATIC
48 #endif // __ANDROID_NDK__
49 
50 using namespace lldb;
51 using namespace lldb_private;
52 
53 #if defined(_WIN32)
54 typedef const char *set_socket_option_arg_type;
55 typedef char *get_socket_option_arg_type;
56 const NativeSocket Socket::kInvalidSocketValue = INVALID_SOCKET;
57 #else  // #if defined(_WIN32)
58 typedef const void *set_socket_option_arg_type;
59 typedef void *get_socket_option_arg_type;
60 const NativeSocket Socket::kInvalidSocketValue = -1;
61 #endif // #if defined(_WIN32)
62 
63 namespace {
64 
65 bool IsInterrupted() {
66 #if defined(_WIN32)
67   return ::WSAGetLastError() == WSAEINTR;
68 #else
69   return errno == EINTR;
70 #endif
71 }
72 }
73 
74 Socket::Socket(NativeSocket socket, SocketProtocol protocol, bool should_close)
75     : IOObject(eFDTypeSocket, should_close), m_protocol(protocol),
76       m_socket(socket) {}
77 
78 Socket::~Socket() { Close(); }
79 
80 std::unique_ptr<Socket> Socket::Create(const SocketProtocol protocol,
81                                        bool child_processes_inherit,
82                                        Error &error) {
83   error.Clear();
84 
85   std::unique_ptr<Socket> socket_up;
86   switch (protocol) {
87   case ProtocolTcp:
88     socket_up.reset(new TCPSocket(child_processes_inherit, error));
89     break;
90   case ProtocolUdp:
91     socket_up.reset(new UDPSocket(child_processes_inherit, error));
92     break;
93   case ProtocolUnixDomain:
94 #ifndef LLDB_DISABLE_POSIX
95     socket_up.reset(new DomainSocket(child_processes_inherit, error));
96 #else
97     error.SetErrorString(
98         "Unix domain sockets are not supported on this platform.");
99 #endif
100     break;
101   case ProtocolUnixAbstract:
102 #ifdef __linux__
103     socket_up.reset(new AbstractSocket(child_processes_inherit, error));
104 #else
105     error.SetErrorString(
106         "Abstract domain sockets are not supported on this platform.");
107 #endif
108     break;
109   }
110 
111   if (error.Fail())
112     socket_up.reset();
113 
114   return socket_up;
115 }
116 
117 Error Socket::TcpConnect(llvm::StringRef host_and_port,
118                          bool child_processes_inherit, Socket *&socket) {
119   Log *log(lldb_private::GetLogIfAnyCategoriesSet(LIBLLDB_LOG_COMMUNICATION));
120   if (log)
121     log->Printf("Socket::%s (host/port = %s)", __FUNCTION__,
122                 host_and_port.data());
123 
124   Error error;
125   std::unique_ptr<Socket> connect_socket(
126       Create(ProtocolTcp, child_processes_inherit, error));
127   if (error.Fail())
128     return error;
129 
130   error = connect_socket->Connect(host_and_port);
131   if (error.Success())
132     socket = connect_socket.release();
133 
134   return error;
135 }
136 
137 Error Socket::TcpListen(llvm::StringRef host_and_port,
138                         bool child_processes_inherit, Socket *&socket,
139                         Predicate<uint16_t> *predicate, int backlog) {
140   Log *log(lldb_private::GetLogIfAnyCategoriesSet(LIBLLDB_LOG_CONNECTION));
141   if (log)
142     log->Printf("Socket::%s (%s)", __FUNCTION__, host_and_port.data());
143 
144   Error error;
145   std::string host_str;
146   std::string port_str;
147   int32_t port = INT32_MIN;
148   if (!DecodeHostAndPort(host_and_port, host_str, port_str, port, &error))
149     return error;
150 
151   std::unique_ptr<TCPSocket> listen_socket(
152       new TCPSocket(child_processes_inherit, error));
153   if (error.Fail())
154     return error;
155 
156   error = listen_socket->Listen(host_and_port, backlog);
157   if (error.Success()) {
158     // We were asked to listen on port zero which means we
159     // must now read the actual port that was given to us
160     // as port zero is a special code for "find an open port
161     // for me".
162     if (port == 0)
163       port = listen_socket->GetLocalPortNumber();
164 
165     // Set the port predicate since when doing a listen://<host>:<port>
166     // it often needs to accept the incoming connection which is a blocking
167     // system call. Allowing access to the bound port using a predicate allows
168     // us to wait for the port predicate to be set to a non-zero value from
169     // another thread in an efficient manor.
170     if (predicate)
171       predicate->SetValue(port, eBroadcastAlways);
172     socket = listen_socket.release();
173   }
174 
175   return error;
176 }
177 
178 Error Socket::UdpConnect(llvm::StringRef host_and_port,
179                          bool child_processes_inherit, Socket *&send_socket,
180                          Socket *&recv_socket) {
181   Log *log(lldb_private::GetLogIfAnyCategoriesSet(LIBLLDB_LOG_CONNECTION));
182   if (log)
183     log->Printf("Socket::%s (host/port = %s)", __FUNCTION__,
184                 host_and_port.data());
185 
186   return UDPSocket::Connect(host_and_port, child_processes_inherit, send_socket,
187                             recv_socket);
188 }
189 
190 Error Socket::UnixDomainConnect(llvm::StringRef name,
191                                 bool child_processes_inherit, Socket *&socket) {
192   Error error;
193   std::unique_ptr<Socket> connect_socket(
194       Create(ProtocolUnixDomain, child_processes_inherit, error));
195   if (error.Fail())
196     return error;
197 
198   error = connect_socket->Connect(name);
199   if (error.Success())
200     socket = connect_socket.release();
201 
202   return error;
203 }
204 
205 Error Socket::UnixDomainAccept(llvm::StringRef name,
206                                bool child_processes_inherit, Socket *&socket) {
207   Error error;
208   std::unique_ptr<Socket> listen_socket(
209       Create(ProtocolUnixDomain, child_processes_inherit, error));
210   if (error.Fail())
211     return error;
212 
213   error = listen_socket->Listen(name, 5);
214   if (error.Fail())
215     return error;
216 
217   error = listen_socket->Accept(name, child_processes_inherit, socket);
218   return error;
219 }
220 
221 Error Socket::UnixAbstractConnect(llvm::StringRef name,
222                                   bool child_processes_inherit,
223                                   Socket *&socket) {
224   Error error;
225   std::unique_ptr<Socket> connect_socket(
226       Create(ProtocolUnixAbstract, child_processes_inherit, error));
227   if (error.Fail())
228     return error;
229 
230   error = connect_socket->Connect(name);
231   if (error.Success())
232     socket = connect_socket.release();
233   return error;
234 }
235 
236 Error Socket::UnixAbstractAccept(llvm::StringRef name,
237                                  bool child_processes_inherit,
238                                  Socket *&socket) {
239   Error error;
240   std::unique_ptr<Socket> listen_socket(
241       Create(ProtocolUnixAbstract, child_processes_inherit, error));
242   if (error.Fail())
243     return error;
244 
245   error = listen_socket->Listen(name, 5);
246   if (error.Fail())
247     return error;
248 
249   error = listen_socket->Accept(name, child_processes_inherit, socket);
250   return error;
251 }
252 
253 bool Socket::DecodeHostAndPort(llvm::StringRef host_and_port,
254                                std::string &host_str, std::string &port_str,
255                                int32_t &port, Error *error_ptr) {
256   static RegularExpression g_regex(llvm::StringRef("([^:]+):([0-9]+)"));
257   RegularExpression::Match regex_match(2);
258   if (g_regex.Execute(host_and_port, &regex_match)) {
259     if (regex_match.GetMatchAtIndex(host_and_port.data(), 1, host_str) &&
260         regex_match.GetMatchAtIndex(host_and_port.data(), 2, port_str)) {
261       bool ok = false;
262       port = StringConvert::ToUInt32(port_str.c_str(), UINT32_MAX, 10, &ok);
263       if (ok && port <= UINT16_MAX) {
264         if (error_ptr)
265           error_ptr->Clear();
266         return true;
267       }
268       // port is too large
269       if (error_ptr)
270         error_ptr->SetErrorStringWithFormat(
271             "invalid host:port specification: '%s'", host_and_port.data());
272       return false;
273     }
274   }
275 
276   // If this was unsuccessful, then check if it's simply a signed 32-bit
277   // integer, representing
278   // a port with an empty host.
279   host_str.clear();
280   port_str.clear();
281   bool ok = false;
282   port = StringConvert::ToUInt32(host_and_port.data(), UINT32_MAX, 10, &ok);
283   if (ok && port < UINT16_MAX) {
284     port_str = host_and_port;
285     if (error_ptr)
286       error_ptr->Clear();
287     return true;
288   }
289 
290   if (error_ptr)
291     error_ptr->SetErrorStringWithFormat("invalid host:port specification: '%s'",
292                                         host_and_port.data());
293   return false;
294 }
295 
296 IOObject::WaitableHandle Socket::GetWaitableHandle() {
297   // TODO: On Windows, use WSAEventSelect
298   return m_socket;
299 }
300 
301 Error Socket::Read(void *buf, size_t &num_bytes) {
302   Error error;
303   int bytes_received = 0;
304   do {
305     bytes_received = ::recv(m_socket, static_cast<char *>(buf), num_bytes, 0);
306   } while (bytes_received < 0 && IsInterrupted());
307 
308   if (bytes_received < 0) {
309     SetLastError(error);
310     num_bytes = 0;
311   } else
312     num_bytes = bytes_received;
313 
314   Log *log(lldb_private::GetLogIfAnyCategoriesSet(LIBLLDB_LOG_COMMUNICATION));
315   if (log) {
316     log->Printf("%p Socket::Read() (socket = %" PRIu64
317                 ", src = %p, src_len = %" PRIu64 ", flags = 0) => %" PRIi64
318                 " (error = %s)",
319                 static_cast<void *>(this), static_cast<uint64_t>(m_socket), buf,
320                 static_cast<uint64_t>(num_bytes),
321                 static_cast<int64_t>(bytes_received), error.AsCString());
322   }
323 
324   return error;
325 }
326 
327 Error Socket::Write(const void *buf, size_t &num_bytes) {
328   Error error;
329   int bytes_sent = 0;
330   do {
331     bytes_sent = Send(buf, num_bytes);
332   } while (bytes_sent < 0 && IsInterrupted());
333 
334   if (bytes_sent < 0) {
335     SetLastError(error);
336     num_bytes = 0;
337   } else
338     num_bytes = bytes_sent;
339 
340   Log *log(lldb_private::GetLogIfAnyCategoriesSet(LIBLLDB_LOG_COMMUNICATION));
341   if (log) {
342     log->Printf("%p Socket::Write() (socket = %" PRIu64
343                 ", src = %p, src_len = %" PRIu64 ", flags = 0) => %" PRIi64
344                 " (error = %s)",
345                 static_cast<void *>(this), static_cast<uint64_t>(m_socket), buf,
346                 static_cast<uint64_t>(num_bytes),
347                 static_cast<int64_t>(bytes_sent), error.AsCString());
348   }
349 
350   return error;
351 }
352 
353 Error Socket::PreDisconnect() {
354   Error error;
355   return error;
356 }
357 
358 Error Socket::Close() {
359   Error error;
360   if (!IsValid() || !m_should_close_fd)
361     return error;
362 
363   Log *log(lldb_private::GetLogIfAnyCategoriesSet(LIBLLDB_LOG_CONNECTION));
364   if (log)
365     log->Printf("%p Socket::Close (fd = %i)", static_cast<void *>(this),
366                 m_socket);
367 
368 #if defined(_WIN32)
369   bool success = !!closesocket(m_socket);
370 #else
371   bool success = !!::close(m_socket);
372 #endif
373   // A reference to a FD was passed in, set it to an invalid value
374   m_socket = kInvalidSocketValue;
375   if (!success) {
376     SetLastError(error);
377   }
378 
379   return error;
380 }
381 
382 int Socket::GetOption(int level, int option_name, int &option_value) {
383   get_socket_option_arg_type option_value_p =
384       reinterpret_cast<get_socket_option_arg_type>(&option_value);
385   socklen_t option_value_size = sizeof(int);
386   return ::getsockopt(m_socket, level, option_name, option_value_p,
387                       &option_value_size);
388 }
389 
390 int Socket::SetOption(int level, int option_name, int option_value) {
391   set_socket_option_arg_type option_value_p =
392       reinterpret_cast<get_socket_option_arg_type>(&option_value);
393   return ::setsockopt(m_socket, level, option_name, option_value_p,
394                       sizeof(option_value));
395 }
396 
397 size_t Socket::Send(const void *buf, const size_t num_bytes) {
398   return ::send(m_socket, static_cast<const char *>(buf), num_bytes, 0);
399 }
400 
401 void Socket::SetLastError(Error &error) {
402 #if defined(_WIN32)
403   error.SetError(::WSAGetLastError(), lldb::eErrorTypeWin32);
404 #else
405   error.SetErrorToErrno();
406 #endif
407 }
408 
409 NativeSocket Socket::CreateSocket(const int domain, const int type,
410                                   const int protocol,
411                                   bool child_processes_inherit, Error &error) {
412   error.Clear();
413   auto socketType = type;
414 #ifdef SOCK_CLOEXEC
415   if (!child_processes_inherit)
416     socketType |= SOCK_CLOEXEC;
417 #endif
418   auto sock = ::socket(domain, socketType, protocol);
419   if (sock == kInvalidSocketValue)
420     SetLastError(error);
421 
422   return sock;
423 }
424 
425 NativeSocket Socket::AcceptSocket(NativeSocket sockfd, struct sockaddr *addr,
426                                   socklen_t *addrlen,
427                                   bool child_processes_inherit, Error &error) {
428   error.Clear();
429 #if defined(ANDROID_ARM_BUILD_STATIC) || defined(ANDROID_MIPS_BUILD_STATIC)
430   // Temporary workaround for statically linking Android lldb-server with the
431   // latest API.
432   int fd = syscall(__NR_accept, sockfd, addr, addrlen);
433   if (fd >= 0 && !child_processes_inherit) {
434     int flags = ::fcntl(fd, F_GETFD);
435     if (flags != -1 && ::fcntl(fd, F_SETFD, flags | FD_CLOEXEC) != -1)
436       return fd;
437     SetLastError(error);
438     close(fd);
439   }
440   return fd;
441 #elif defined(SOCK_CLOEXEC)
442   int flags = 0;
443   if (!child_processes_inherit) {
444     flags |= SOCK_CLOEXEC;
445   }
446 #if defined(__NetBSD__)
447   NativeSocket fd = ::paccept(sockfd, addr, addrlen, nullptr, flags);
448 #else
449   NativeSocket fd = ::accept4(sockfd, addr, addrlen, flags);
450 #endif
451 #else
452   NativeSocket fd = ::accept(sockfd, addr, addrlen);
453 #endif
454   if (fd == kInvalidSocketValue)
455     SetLastError(error);
456   return fd;
457 }
458