1//===-- UDPSocket.cpp -------------------------------------------*- C++ -*-===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8
9#include "lldb/Host/common/UDPSocket.h"
10
11#include "lldb/Host/Config.h"
12#include "lldb/Utility/Log.h"
13
14#if LLDB_ENABLE_POSIX
15#include <arpa/inet.h>
16#include <sys/socket.h>
17#endif
18
19#include <memory>
20
21using namespace lldb;
22using namespace lldb_private;
23
24namespace {
25
26const int kDomain = AF_INET;
27const int kType = SOCK_DGRAM;
28
29static const char *g_not_supported_error = "Not supported";
30}
31
32UDPSocket::UDPSocket(NativeSocket socket) : Socket(ProtocolUdp, true, true) {
33  m_socket = socket;
34}
35
36UDPSocket::UDPSocket(bool should_close, bool child_processes_inherit)
37    : Socket(ProtocolUdp, should_close, child_processes_inherit) {}
38
39size_t UDPSocket::Send(const void *buf, const size_t num_bytes) {
40  return ::sendto(m_socket, static_cast<const char *>(buf), num_bytes, 0,
41                  m_sockaddr, m_sockaddr.GetLength());
42}
43
44Status UDPSocket::Connect(llvm::StringRef name) {
45  return Status("%s", g_not_supported_error);
46}
47
48Status UDPSocket::Listen(llvm::StringRef name, int backlog) {
49  return Status("%s", g_not_supported_error);
50}
51
52Status UDPSocket::Accept(Socket *&socket) {
53  return Status("%s", g_not_supported_error);
54}
55
56Status UDPSocket::Connect(llvm::StringRef name, bool child_processes_inherit,
57                          Socket *&socket) {
58  std::unique_ptr<UDPSocket> final_socket;
59
60  Log *log(lldb_private::GetLogIfAnyCategoriesSet(LIBLLDB_LOG_CONNECTION));
61  LLDB_LOGF(log, "UDPSocket::%s (host/port = %s)", __FUNCTION__, name.data());
62
63  Status error;
64  std::string host_str;
65  std::string port_str;
66  int32_t port = INT32_MIN;
67  if (!DecodeHostAndPort(name, host_str, port_str, port, &error))
68    return error;
69
70  // At this point we have setup the receive port, now we need to setup the UDP
71  // send socket
72
73  struct addrinfo hints;
74  struct addrinfo *service_info_list = nullptr;
75
76  ::memset(&hints, 0, sizeof(hints));
77  hints.ai_family = kDomain;
78  hints.ai_socktype = kType;
79  int err = ::getaddrinfo(host_str.c_str(), port_str.c_str(), &hints,
80                          &service_info_list);
81  if (err != 0) {
82    error.SetErrorStringWithFormat(
83#if defined(_WIN32) && defined(UNICODE)
84        "getaddrinfo(%s, %s, &hints, &info) returned error %i (%S)",
85#else
86        "getaddrinfo(%s, %s, &hints, &info) returned error %i (%s)",
87#endif
88        host_str.c_str(), port_str.c_str(), err, gai_strerror(err));
89    return error;
90  }
91
92  for (struct addrinfo *service_info_ptr = service_info_list;
93       service_info_ptr != nullptr;
94       service_info_ptr = service_info_ptr->ai_next) {
95    auto send_fd = CreateSocket(
96        service_info_ptr->ai_family, service_info_ptr->ai_socktype,
97        service_info_ptr->ai_protocol, child_processes_inherit, error);
98    if (error.Success()) {
99      final_socket.reset(new UDPSocket(send_fd));
100      final_socket->m_sockaddr = service_info_ptr;
101      break;
102    } else
103      continue;
104  }
105
106  ::freeaddrinfo(service_info_list);
107
108  if (!final_socket)
109    return error;
110
111  SocketAddress bind_addr;
112
113  // Only bind to the loopback address if we are expecting a connection from
114  // localhost to avoid any firewall issues.
115  const bool bind_addr_success = (host_str == "127.0.0.1" || host_str == "localhost")
116                                     ? bind_addr.SetToLocalhost(kDomain, port)
117                                     : bind_addr.SetToAnyAddress(kDomain, port);
118
119  if (!bind_addr_success) {
120    error.SetErrorString("Failed to get hostspec to bind for");
121    return error;
122  }
123
124  bind_addr.SetPort(0); // Let the source port # be determined dynamically
125
126  err = ::bind(final_socket->GetNativeSocket(), bind_addr, bind_addr.GetLength());
127
128  struct sockaddr_in source_info;
129  socklen_t address_len = sizeof (struct sockaddr_in);
130  err = ::getsockname(final_socket->GetNativeSocket(), (struct sockaddr *) &source_info, &address_len);
131
132  socket = final_socket.release();
133  error.Clear();
134  return error;
135}
136
137std::string UDPSocket::GetRemoteConnectionURI() const {
138  if (m_socket != kInvalidSocketValue) {
139    return llvm::formatv("udp://[{0}]:{1}", m_sockaddr.GetIPAddress(),
140                         m_sockaddr.GetPort());
141  }
142  return "";
143}
144