1 //===-- UDPSocket.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/common/UDPSocket.h"
11 
12 #include "lldb/Host/Config.h"
13 #include "lldb/Utility/Log.h"
14 
15 #ifndef LLDB_DISABLE_POSIX
16 #include <arpa/inet.h>
17 #include <sys/socket.h>
18 #endif
19 
20 #include <memory>
21 
22 using namespace lldb;
23 using namespace lldb_private;
24 
25 namespace {
26 
27 const int kDomain = AF_INET;
28 const int kType = SOCK_DGRAM;
29 
30 static const char *g_not_supported_error = "Not supported";
31 }
32 
33 UDPSocket::UDPSocket(NativeSocket socket) : Socket(ProtocolUdp, true, true) {
34   m_socket = socket;
35 }
36 
37 UDPSocket::UDPSocket(bool should_close, bool child_processes_inherit)
38     : Socket(ProtocolUdp, should_close, child_processes_inherit) {}
39 
40 size_t UDPSocket::Send(const void *buf, const size_t num_bytes) {
41   return ::sendto(m_socket, static_cast<const char *>(buf), num_bytes, 0,
42                   m_sockaddr, m_sockaddr.GetLength());
43 }
44 
45 Status UDPSocket::Connect(llvm::StringRef name) {
46   return Status("%s", g_not_supported_error);
47 }
48 
49 Status UDPSocket::Listen(llvm::StringRef name, int backlog) {
50   return Status("%s", g_not_supported_error);
51 }
52 
53 Status UDPSocket::Accept(Socket *&socket) {
54   return Status("%s", g_not_supported_error);
55 }
56 
57 Status UDPSocket::Connect(llvm::StringRef name, bool child_processes_inherit,
58                           Socket *&socket) {
59   std::unique_ptr<UDPSocket> final_socket;
60 
61   Log *log(lldb_private::GetLogIfAnyCategoriesSet(LIBLLDB_LOG_CONNECTION));
62   if (log)
63     log->Printf("UDPSocket::%s (host/port = %s)", __FUNCTION__, name.data());
64 
65   Status error;
66   std::string host_str;
67   std::string port_str;
68   int32_t port = INT32_MIN;
69   if (!DecodeHostAndPort(name, host_str, port_str, port, &error))
70     return error;
71 
72   // At this point we have setup the receive port, now we need to
73   // setup the UDP send socket
74 
75   struct addrinfo hints;
76   struct addrinfo *service_info_list = nullptr;
77 
78   ::memset(&hints, 0, sizeof(hints));
79   hints.ai_family = kDomain;
80   hints.ai_socktype = kType;
81   int err = ::getaddrinfo(host_str.c_str(), port_str.c_str(), &hints,
82                           &service_info_list);
83   if (err != 0) {
84     error.SetErrorStringWithFormat(
85 #if defined(_MSC_VER) && defined(UNICODE)
86         "getaddrinfo(%s, %s, &hints, &info) returned error %i (%S)",
87 #else
88         "getaddrinfo(%s, %s, &hints, &info) returned error %i (%s)",
89 #endif
90         host_str.c_str(), port_str.c_str(), err, gai_strerror(err));
91     return error;
92   }
93 
94   for (struct addrinfo *service_info_ptr = service_info_list;
95        service_info_ptr != nullptr;
96        service_info_ptr = service_info_ptr->ai_next) {
97     auto send_fd = CreateSocket(
98         service_info_ptr->ai_family, service_info_ptr->ai_socktype,
99         service_info_ptr->ai_protocol, child_processes_inherit, error);
100     if (error.Success()) {
101       final_socket.reset(new UDPSocket(send_fd));
102       final_socket->m_sockaddr = service_info_ptr;
103       break;
104     } else
105       continue;
106   }
107 
108   ::freeaddrinfo(service_info_list);
109 
110   if (!final_socket)
111     return error;
112 
113   SocketAddress bind_addr;
114 
115   // Only bind to the loopback address if we are expecting a connection from
116   // localhost to avoid any firewall issues.
117   const bool bind_addr_success = (host_str == "127.0.0.1" || host_str == "localhost")
118                                      ? bind_addr.SetToLocalhost(kDomain, port)
119                                      : bind_addr.SetToAnyAddress(kDomain, port);
120 
121   if (!bind_addr_success) {
122     error.SetErrorString("Failed to get hostspec to bind for");
123     return error;
124   }
125 
126   bind_addr.SetPort(0); // Let the source port # be determined dynamically
127 
128   err = ::bind(final_socket->GetNativeSocket(), bind_addr, bind_addr.GetLength());
129 
130   struct sockaddr_in source_info;
131   socklen_t address_len = sizeof (struct sockaddr_in);
132   err = ::getsockname(final_socket->GetNativeSocket(), (struct sockaddr *) &source_info, &address_len);
133 
134   socket = final_socket.release();
135   error.Clear();
136   return error;
137 }
138