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