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