Botan  2.19.1
Crypto and TLS for C++11
socket_udp.cpp
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1 /*
2 * (C) 2015,2016,2017 Jack Lloyd
3 * (C) 2016 Daniel Neus
4 * (C) 2019 Nuno Goncalves <nunojpg@gmail.com>
5 *
6 * Botan is released under the Simplified BSD License (see license.txt)
7 */
8 
9 #include <botan/internal/socket_udp.h>
10 #include <botan/internal/uri.h>
11 #include <botan/exceptn.h>
12 #include <botan/mem_ops.h>
13 #include <chrono>
14 
15 #if defined(BOTAN_HAS_BOOST_ASIO)
16  /*
17  * We don't need serial port support anyway, and asking for it
18  * causes macro conflicts with Darwin's termios.h when this
19  * file is included in the amalgamation. GH #350
20  */
21  #define BOOST_ASIO_DISABLE_SERIAL_PORT
22  #include <boost/asio.hpp>
23  #include <boost/asio/system_timer.hpp>
24 #elif defined(BOTAN_TARGET_OS_HAS_SOCKETS)
25  #include <sys/socket.h>
26  #include <sys/time.h>
27  #include <netinet/in.h>
28  #include <netdb.h>
29  #include <string.h>
30  #include <unistd.h>
31  #include <errno.h>
32  #include <fcntl.h>
33 
34 #elif defined(BOTAN_TARGET_OS_HAS_WINSOCK2)
35  #include <ws2tcpip.h>
36 #endif
37 
38 namespace Botan {
39 
40 namespace {
41 
42 #if defined(BOTAN_HAS_BOOST_ASIO)
43 class Asio_SocketUDP final : public OS::SocketUDP
44  {
45  public:
46  Asio_SocketUDP(const std::string& hostname,
47  const std::string& service,
48  std::chrono::microseconds timeout) :
49  m_timeout(timeout), m_timer(m_io), m_udp(m_io)
50  {
51  m_timer.expires_from_now(m_timeout);
52  check_timeout();
53 
54  boost::asio::ip::udp::resolver resolver(m_io);
55  boost::asio::ip::udp::resolver::query query(hostname, service);
56  boost::asio::ip::udp::resolver::iterator dns_iter = resolver.resolve(query);
57 
58  boost::system::error_code ec = boost::asio::error::would_block;
59 
60  auto connect_cb = [&ec](const boost::system::error_code& e,
61  boost::asio::ip::udp::resolver::iterator) { ec = e; };
62 
63  boost::asio::async_connect(m_udp, dns_iter, connect_cb);
64 
65  while(ec == boost::asio::error::would_block)
66  {
67  m_io.run_one();
68  }
69 
70  if(ec)
71  { throw boost::system::system_error(ec); }
72  if(m_udp.is_open() == false)
73  { throw System_Error("Connection to host " + hostname + " failed"); }
74  }
75 
76  void write(const uint8_t buf[], size_t len) override
77  {
78  m_timer.expires_from_now(m_timeout);
79 
80  boost::system::error_code ec = boost::asio::error::would_block;
81 
82  m_udp.async_send(boost::asio::buffer(buf, len),
83  [&ec](boost::system::error_code e, size_t) { ec = e; });
84 
85  while(ec == boost::asio::error::would_block)
86  {
87  m_io.run_one();
88  }
89 
90  if(ec)
91  {
92  throw boost::system::system_error(ec);
93  }
94  }
95 
96  size_t read(uint8_t buf[], size_t len) override
97  {
98  m_timer.expires_from_now(m_timeout);
99 
100  boost::system::error_code ec = boost::asio::error::would_block;
101  size_t got = 0;
102 
103  m_udp.async_receive(boost::asio::buffer(buf, len),
104  [&](boost::system::error_code cb_ec, size_t cb_got) { ec = cb_ec; got = cb_got; });
105 
106  while(ec == boost::asio::error::would_block)
107  {
108  m_io.run_one();
109  }
110 
111  if(ec)
112  {
113  if(ec == boost::asio::error::eof)
114  { return 0; }
115  throw boost::system::system_error(ec); // Some other error.
116  }
117 
118  return got;
119  }
120 
121  private:
122  void check_timeout()
123  {
124  if(m_udp.is_open() && m_timer.expires_at() < std::chrono::system_clock::now())
125  {
126  boost::system::error_code err;
127  m_udp.close(err);
128  }
129 
130  m_timer.async_wait(std::bind(&Asio_SocketUDP::check_timeout, this));
131  }
132 
133  const std::chrono::microseconds m_timeout;
134  boost::asio::io_service m_io;
135  boost::asio::system_timer m_timer;
136  boost::asio::ip::udp::socket m_udp;
137  };
138 #elif defined(BOTAN_TARGET_OS_HAS_SOCKETS) || defined(BOTAN_TARGET_OS_HAS_WINSOCK2)
139 class BSD_SocketUDP final : public OS::SocketUDP
140  {
141  public:
142  BSD_SocketUDP(const std::string& hostname,
143  const std::string& service,
144  std::chrono::microseconds timeout) : m_timeout(timeout)
145  {
146  socket_init();
147 
148  m_socket = invalid_socket();
149 
150  addrinfo* res;
151  addrinfo hints;
152  clear_mem(&hints, 1);
153  hints.ai_family = AF_UNSPEC;
154  hints.ai_socktype = SOCK_DGRAM;
155 
156  int rc = ::getaddrinfo(hostname.c_str(), service.c_str(), &hints, &res);
157 
158  if(rc != 0)
159  {
160  throw System_Error("Name resolution failed for " + hostname, rc);
161  }
162 
163  for(addrinfo* rp = res; (m_socket == invalid_socket()) && (rp != nullptr); rp = rp->ai_next)
164  {
165  if(rp->ai_family != AF_INET && rp->ai_family != AF_INET6)
166  { continue; }
167 
168  m_socket = ::socket(rp->ai_family, rp->ai_socktype, rp->ai_protocol);
169 
170  if(m_socket == invalid_socket())
171  {
172  // unsupported socket type?
173  continue;
174  }
175 
176  set_nonblocking(m_socket);
177  memcpy(&sa, res->ai_addr, res->ai_addrlen);
178  salen = static_cast<socklen_t>(res->ai_addrlen);
179  }
180 
181  ::freeaddrinfo(res);
182 
183  if(m_socket == invalid_socket())
184  {
185  throw System_Error("Connecting to " + hostname +
186  " for service " + service + " failed", errno);
187  }
188  }
189 
190  ~BSD_SocketUDP()
191  {
192  close_socket(m_socket);
193  m_socket = invalid_socket();
194  socket_fini();
195  }
196 
197  void write(const uint8_t buf[], size_t len) override
198  {
199  fd_set write_set;
200  FD_ZERO(&write_set);
201  FD_SET(m_socket, &write_set);
202 
203  size_t sent_so_far = 0;
204  while(sent_so_far != len)
205  {
206  struct timeval timeout = make_timeout_tv();
207  int active = ::select(static_cast<int>(m_socket + 1), nullptr, &write_set, nullptr, &timeout);
208 
209  if(active == 0)
210  { throw System_Error("Timeout during socket write"); }
211 
212  const size_t left = len - sent_so_far;
213  socket_op_ret_type sent = ::sendto(m_socket, cast_uint8_ptr_to_char(buf + sent_so_far),
214  static_cast<sendrecv_len_type>(left), 0,
215  reinterpret_cast<sockaddr*>(&sa), salen);
216  if(sent < 0)
217  { throw System_Error("Socket write failed", errno); }
218  else
219  { sent_so_far += static_cast<size_t>(sent); }
220  }
221  }
222 
223  size_t read(uint8_t buf[], size_t len) override
224  {
225  fd_set read_set;
226  FD_ZERO(&read_set);
227  FD_SET(m_socket, &read_set);
228 
229  struct timeval timeout = make_timeout_tv();
230  int active = ::select(static_cast<int>(m_socket + 1), &read_set, nullptr, nullptr, &timeout);
231 
232  if(active == 0)
233  { throw System_Error("Timeout during socket read"); }
234 
235  socket_op_ret_type got = ::recvfrom(m_socket, cast_uint8_ptr_to_char(buf), static_cast<sendrecv_len_type>(len), 0, nullptr, nullptr);
236 
237  if(got < 0)
238  { throw System_Error("Socket read failed", errno); }
239 
240  return static_cast<size_t>(got);
241  }
242 
243  private:
244 #if defined(BOTAN_TARGET_OS_HAS_WINSOCK2)
245  typedef SOCKET socket_type;
246  typedef int socket_op_ret_type;
247  typedef int sendrecv_len_type;
248  static socket_type invalid_socket() { return INVALID_SOCKET; }
249  static void close_socket(socket_type s) { ::closesocket(s); }
250  static std::string get_last_socket_error() { return std::to_string(::WSAGetLastError()); }
251 
252  static bool nonblocking_connect_in_progress()
253  {
254  return (::WSAGetLastError() == WSAEWOULDBLOCK);
255  }
256 
257  static void set_nonblocking(socket_type s)
258  {
259  u_long nonblocking = 1;
260  ::ioctlsocket(s, FIONBIO, &nonblocking);
261  }
262 
263  static void socket_init()
264  {
265  WSAData wsa_data;
266  WORD wsa_version = MAKEWORD(2, 2);
267 
268  if(::WSAStartup(wsa_version, &wsa_data) != 0)
269  {
270  throw System_Error("WSAStartup() failed", WSAGetLastError());
271  }
272 
273  if(LOBYTE(wsa_data.wVersion) != 2 || HIBYTE(wsa_data.wVersion) != 2)
274  {
275  ::WSACleanup();
276  throw System_Error("Could not find a usable version of Winsock.dll");
277  }
278  }
279 
280  static void socket_fini()
281  {
282  ::WSACleanup();
283  }
284 #else
285  typedef int socket_type;
286  typedef ssize_t socket_op_ret_type;
287  typedef size_t sendrecv_len_type;
288  static socket_type invalid_socket() { return -1; }
289  static void close_socket(socket_type s) { ::close(s); }
290  static std::string get_last_socket_error() { return ::strerror(errno); }
291  static bool nonblocking_connect_in_progress() { return (errno == EINPROGRESS); }
292  static void set_nonblocking(socket_type s)
293  {
294  if(::fcntl(s, F_SETFL, O_NONBLOCK) < 0)
295  { throw System_Error("Setting socket to non-blocking state failed", errno); }
296  }
297 
298  static void socket_init() {}
299  static void socket_fini() {}
300 #endif
301  sockaddr_storage sa;
302  socklen_t salen;
303  struct timeval make_timeout_tv() const
304  {
305  struct timeval tv;
306  tv.tv_sec = static_cast<decltype(timeval::tv_sec)>(m_timeout.count() / 1000000);
307  tv.tv_usec = static_cast<decltype(timeval::tv_usec)>(m_timeout.count() % 1000000);;
308  return tv;
309  }
310 
311  const std::chrono::microseconds m_timeout;
312  socket_type m_socket;
313  };
314 #endif
315 }
316 
317 std::unique_ptr<OS::SocketUDP>
318 OS::open_socket_udp(const std::string& hostname,
319  const std::string& service,
320  std::chrono::microseconds timeout)
321  {
322 #if defined(BOTAN_HAS_BOOST_ASIO)
323  return std::unique_ptr<OS::SocketUDP>(new Asio_SocketUDP(hostname, service, timeout));
324 #elif defined(BOTAN_TARGET_OS_HAS_SOCKETS) || defined(BOTAN_TARGET_OS_HAS_WINSOCK2)
325  return std::unique_ptr<OS::SocketUDP>(new BSD_SocketUDP(hostname, service, timeout));
326 #else
327  BOTAN_UNUSED(hostname);
328  BOTAN_UNUSED(service);
329  BOTAN_UNUSED(timeout);
330  return std::unique_ptr<OS::SocketUDP>();
331 #endif
332  }
333 
334 std::unique_ptr<OS::SocketUDP>
335 OS::open_socket_udp(const std::string& uri_string,
336  std::chrono::microseconds timeout)
337  {
338  const auto uri = URI::fromAny(uri_string);
339  if(uri.port == 0)
340  { throw Invalid_Argument("UDP port not specified"); }
341  return open_socket_udp(uri.host, std::to_string(uri.port), timeout);
342  }
343 
344 }
std::unique_ptr< SocketUDP > BOTAN_TEST_API open_socket_udp(const std::string &hostname, const std::string &service, std::chrono::microseconds timeout)
Definition: socket_udp.cpp:318
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Definition: mem_ops.h:115
#define O_NONBLOCK
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Definition: socket_udp.cpp:134
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#define BOTAN_UNUSED(...)
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const char * cast_uint8_ptr_to_char(const uint8_t *b)
Definition: mem_ops.h:195
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Definition: socket_udp.cpp:135
const std::chrono::microseconds m_timeout
Definition: socket_udp.cpp:133
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Definition: socket_udp.cpp:136
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