1 //===-- TCPSocket.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 #if defined(_MSC_VER)
11 #define _WINSOCK_DEPRECATED_NO_WARNINGS
12 #endif
13 
14 #include "lldb/Host/common/TCPSocket.h"
15 
16 #include "lldb/Host/Config.h"
17 #include "lldb/Host/MainLoop.h"
18 #include "lldb/Utility/Log.h"
19 
20 #include "llvm/Config/llvm-config.h"
21 #include "llvm/Support/raw_ostream.h"
22 
23 #ifndef LLDB_DISABLE_POSIX
24 #include <arpa/inet.h>
25 #include <netinet/tcp.h>
26 #include <sys/socket.h>
27 #endif
28 
29 #if defined(LLVM_ON_WIN32)
30 #include <winsock2.h>
31 #endif
32 
33 #ifdef LLVM_ON_WIN32
34 #define CLOSE_SOCKET closesocket
35 typedef const char *set_socket_option_arg_type;
36 #else
37 #define CLOSE_SOCKET ::close
38 typedef const void *set_socket_option_arg_type;
39 #endif
40 
41 using namespace lldb;
42 using namespace lldb_private;
43 
44 namespace {
45 const int kType = SOCK_STREAM;
46 }
47 
48 TCPSocket::TCPSocket(bool should_close, bool child_processes_inherit)
49     : Socket(ProtocolTcp, should_close, child_processes_inherit) {}
50 
51 TCPSocket::TCPSocket(NativeSocket socket, const TCPSocket &listen_socket)
52     : Socket(ProtocolTcp, listen_socket.m_should_close_fd,
53              listen_socket.m_child_processes_inherit) {
54   m_socket = socket;
55 }
56 
57 TCPSocket::TCPSocket(NativeSocket socket, bool should_close,
58                      bool child_processes_inherit)
59     : Socket(ProtocolTcp, should_close, child_processes_inherit) {
60   m_socket = socket;
61 }
62 
63 TCPSocket::~TCPSocket() { CloseListenSockets(); }
64 
65 bool TCPSocket::IsValid() const {
66   return m_socket != kInvalidSocketValue || m_listen_sockets.size() != 0;
67 }
68 
69 // Return the port number that is being used by the socket.
70 uint16_t TCPSocket::GetLocalPortNumber() const {
71   if (m_socket != kInvalidSocketValue) {
72     SocketAddress sock_addr;
73     socklen_t sock_addr_len = sock_addr.GetMaxLength();
74     if (::getsockname(m_socket, sock_addr, &sock_addr_len) == 0)
75       return sock_addr.GetPort();
76   } else if (!m_listen_sockets.empty()) {
77     SocketAddress sock_addr;
78     socklen_t sock_addr_len = sock_addr.GetMaxLength();
79     if (::getsockname(m_listen_sockets.begin()->first, sock_addr,
80                       &sock_addr_len) == 0)
81       return sock_addr.GetPort();
82   }
83   return 0;
84 }
85 
86 std::string TCPSocket::GetLocalIPAddress() const {
87   // We bound to port zero, so we need to figure out which port we actually
88   // bound to
89   if (m_socket != kInvalidSocketValue) {
90     SocketAddress sock_addr;
91     socklen_t sock_addr_len = sock_addr.GetMaxLength();
92     if (::getsockname(m_socket, sock_addr, &sock_addr_len) == 0)
93       return sock_addr.GetIPAddress();
94   }
95   return "";
96 }
97 
98 uint16_t TCPSocket::GetRemotePortNumber() const {
99   if (m_socket != kInvalidSocketValue) {
100     SocketAddress sock_addr;
101     socklen_t sock_addr_len = sock_addr.GetMaxLength();
102     if (::getpeername(m_socket, sock_addr, &sock_addr_len) == 0)
103       return sock_addr.GetPort();
104   }
105   return 0;
106 }
107 
108 std::string TCPSocket::GetRemoteIPAddress() const {
109   // We bound to port zero, so we need to figure out which port we actually
110   // bound to
111   if (m_socket != kInvalidSocketValue) {
112     SocketAddress sock_addr;
113     socklen_t sock_addr_len = sock_addr.GetMaxLength();
114     if (::getpeername(m_socket, sock_addr, &sock_addr_len) == 0)
115       return sock_addr.GetIPAddress();
116   }
117   return "";
118 }
119 
120 Status TCPSocket::CreateSocket(int domain) {
121   Status error;
122   if (IsValid())
123     error = Close();
124   if (error.Fail())
125     return error;
126   m_socket = Socket::CreateSocket(domain, kType, IPPROTO_TCP,
127                                   m_child_processes_inherit, error);
128   return error;
129 }
130 
131 Status TCPSocket::Connect(llvm::StringRef name) {
132 
133   Log *log(lldb_private::GetLogIfAnyCategoriesSet(LIBLLDB_LOG_COMMUNICATION));
134   if (log)
135     log->Printf("TCPSocket::%s (host/port = %s)", __FUNCTION__, name.data());
136 
137   Status error;
138   std::string host_str;
139   std::string port_str;
140   int32_t port = INT32_MIN;
141   if (!DecodeHostAndPort(name, host_str, port_str, port, &error))
142     return error;
143 
144   auto addresses = lldb_private::SocketAddress::GetAddressInfo(
145       host_str.c_str(), NULL, AF_UNSPEC, SOCK_STREAM, IPPROTO_TCP);
146   for (auto address : addresses) {
147     error = CreateSocket(address.GetFamily());
148     if (error.Fail())
149       continue;
150 
151     address.SetPort(port);
152 
153     if (-1 == ::connect(GetNativeSocket(), &address.sockaddr(),
154                         address.GetLength())) {
155       CLOSE_SOCKET(GetNativeSocket());
156       continue;
157     }
158 
159     SetOptionNoDelay();
160 
161     error.Clear();
162     return error;
163   }
164 
165   error.SetErrorString("Failed to connect port");
166   return error;
167 }
168 
169 Status TCPSocket::Listen(llvm::StringRef name, int backlog) {
170   Log *log(lldb_private::GetLogIfAnyCategoriesSet(LIBLLDB_LOG_CONNECTION));
171   if (log)
172     log->Printf("TCPSocket::%s (%s)", __FUNCTION__, name.data());
173 
174   Status error;
175   std::string host_str;
176   std::string port_str;
177   int32_t port = INT32_MIN;
178   if (!DecodeHostAndPort(name, host_str, port_str, port, &error))
179     return error;
180 
181   if (host_str == "*")
182     host_str = "0.0.0.0";
183   auto addresses = lldb_private::SocketAddress::GetAddressInfo(
184       host_str.c_str(), NULL, AF_UNSPEC, SOCK_STREAM, IPPROTO_TCP);
185   for (auto address : addresses) {
186     int fd = Socket::CreateSocket(address.GetFamily(), kType, IPPROTO_TCP,
187                                   m_child_processes_inherit, error);
188     if (error.Fail()) {
189       error.Clear();
190       continue;
191     }
192 
193     // enable local address reuse
194     int option_value = 1;
195     set_socket_option_arg_type option_value_p =
196         reinterpret_cast<set_socket_option_arg_type>(&option_value);
197     ::setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, option_value_p,
198                  sizeof(option_value));
199 
200     address.SetPort(port);
201 
202     int err = ::bind(fd, &address.sockaddr(), address.GetLength());
203     if (-1 != err)
204       err = ::listen(fd, backlog);
205 
206     if (-1 == err) {
207       CLOSE_SOCKET(fd);
208       continue;
209     }
210 
211     if (port == 0) {
212       socklen_t sa_len = address.GetLength();
213       if (getsockname(fd, &address.sockaddr(), &sa_len) == 0)
214         port = address.GetPort();
215     }
216     m_listen_sockets[fd] = address;
217   }
218 
219   if (m_listen_sockets.size() == 0)
220     error.SetErrorString("Failed to connect port");
221   return error;
222 }
223 
224 void TCPSocket::CloseListenSockets() {
225   for (auto socket : m_listen_sockets)
226   CLOSE_SOCKET(socket.first);
227   m_listen_sockets.clear();
228 }
229 
230 Status TCPSocket::Accept(Socket *&conn_socket) {
231   Status error;
232   if (m_listen_sockets.size() == 0) {
233     error.SetErrorString("No open listening sockets!");
234     return error;
235   }
236 
237   int sock = -1;
238   int listen_sock = -1;
239   lldb_private::SocketAddress AcceptAddr;
240   MainLoop accept_loop;
241   std::vector<MainLoopBase::ReadHandleUP> handles;
242   for (auto socket : m_listen_sockets) {
243     auto fd = socket.first;
244     auto inherit = this->m_child_processes_inherit;
245     auto io_sp = IOObjectSP(new TCPSocket(socket.first, false, inherit));
246     handles.emplace_back(accept_loop.RegisterReadObject(
247         io_sp, [fd, inherit, &sock, &AcceptAddr, &error,
248                         &listen_sock](MainLoopBase &loop) {
249           socklen_t sa_len = AcceptAddr.GetMaxLength();
250           sock = AcceptSocket(fd, &AcceptAddr.sockaddr(), &sa_len, inherit,
251                               error);
252           listen_sock = fd;
253           loop.RequestTermination();
254         }, error));
255     if (error.Fail())
256       return error;
257   }
258 
259   bool accept_connection = false;
260   std::unique_ptr<TCPSocket> accepted_socket;
261   // Loop until we are happy with our connection
262   while (!accept_connection) {
263     accept_loop.Run();
264 
265     if (error.Fail())
266         return error;
267 
268     lldb_private::SocketAddress &AddrIn = m_listen_sockets[listen_sock];
269     if (!AddrIn.IsAnyAddr() && AcceptAddr != AddrIn) {
270       CLOSE_SOCKET(sock);
271       llvm::errs() << llvm::formatv(
272           "error: rejecting incoming connection from {0} (expecting {1})",
273           AcceptAddr.GetIPAddress(), AddrIn.GetIPAddress());
274       continue;
275     }
276     accept_connection = true;
277     accepted_socket.reset(new TCPSocket(sock, *this));
278   }
279 
280   if (!accepted_socket)
281     return error;
282 
283   // Keep our TCP packets coming without any delays.
284   accepted_socket->SetOptionNoDelay();
285   error.Clear();
286   conn_socket = accepted_socket.release();
287   return error;
288 }
289 
290 int TCPSocket::SetOptionNoDelay() {
291   return SetOption(IPPROTO_TCP, TCP_NODELAY, 1);
292 }
293 
294 int TCPSocket::SetOptionReuseAddress() {
295   return SetOption(SOL_SOCKET, SO_REUSEADDR, 1);
296 }
297