Botan 2.19.1
Crypto and TLS for C&
socket_udp.cpp
Go to the documentation of this file.
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
38namespace Botan {
39
40namespace {
41
42#if defined(BOTAN_HAS_BOOST_ASIO)
43class 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)
139class 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
317std::unique_ptr<OS::SocketUDP>
318OS::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
334std::unique_ptr<OS::SocketUDP>
335OS::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}
#define BOTAN_UNUSED(...)
Definition: assert.h:142
int(* final)(unsigned char *, CTX *)
#define O_NONBLOCK
std::string to_string(const BER_Object &obj)
Definition: asn1_obj.cpp:213
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
Definition: alg_id.cpp:13
const char * cast_uint8_ptr_to_char(const uint8_t *b)
Definition: mem_ops.h:195
void clear_mem(T *ptr, size_t n)
Definition: mem_ops.h:115
static URI fromAny(const std::string &uri)
Definition: uri.cpp:184