Botan 3.5.0
Crypto and TLS for C&
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
11#include <botan/exceptn.h>
12#include <botan/mem_ops.h>
13#include <botan/internal/fmt.h>
14#include <botan/internal/uri.h>
15#include <chrono>
16
17#if defined(BOTAN_HAS_BOOST_ASIO)
18 /*
19 * We don't need serial port support anyway, and asking for it
20 * causes macro conflicts with Darwin's termios.h when this
21 * file is included in the amalgamation. GH #350
22 */
23 #define BOOST_ASIO_DISABLE_SERIAL_PORT
24 #include <boost/asio.hpp>
25 #include <boost/asio/system_timer.hpp>
26#elif defined(BOTAN_TARGET_OS_HAS_SOCKETS)
27 #include <errno.h>
28 #include <fcntl.h>
29 #include <netdb.h>
30 #include <netinet/in.h>
31 #include <string.h>
32 #include <sys/socket.h>
33 #include <sys/time.h>
34 #include <unistd.h>
35
36#elif defined(BOTAN_TARGET_OS_HAS_WINSOCK2)
37 #include <ws2tcpip.h>
38#endif
39
40namespace Botan {
41
42namespace {
43
44#if defined(BOTAN_HAS_BOOST_ASIO)
45class Asio_SocketUDP final : public OS::SocketUDP {
46 public:
47 Asio_SocketUDP(std::string_view hostname, std::string_view service, std::chrono::microseconds timeout) :
48 m_timeout(timeout), m_timer(m_io), m_udp(m_io) {
49 m_timer.expires_from_now(m_timeout);
50 check_timeout();
51
52 boost::asio::ip::udp::resolver resolver(m_io);
53 boost::asio::ip::udp::resolver::query query(std::string{hostname}, std::string{service});
54 boost::asio::ip::udp::resolver::iterator dns_iter = resolver.resolve(query);
55
56 boost::system::error_code ec = boost::asio::error::would_block;
57
58 auto connect_cb = [&ec](const boost::system::error_code& e, const boost::asio::ip::udp::resolver::iterator&) {
59 ec = e;
60 };
61
62 boost::asio::async_connect(m_udp, dns_iter, connect_cb);
63
64 while(ec == boost::asio::error::would_block) {
65 m_io.run_one();
66 }
67
68 if(ec) {
69 throw boost::system::system_error(ec);
70 }
71 if(m_udp.is_open() == false) {
72 throw System_Error(fmt("Connection to host {} failed", hostname));
73 }
74 }
75
76 void write(const uint8_t buf[], size_t len) override {
77 m_timer.expires_from_now(m_timeout);
78
79 boost::system::error_code ec = boost::asio::error::would_block;
80
81 m_udp.async_send(boost::asio::buffer(buf, len), [&ec](boost::system::error_code e, size_t) { ec = e; });
82
83 while(ec == boost::asio::error::would_block) {
84 m_io.run_one();
85 }
86
87 if(ec) {
88 throw boost::system::system_error(ec);
89 }
90 }
91
92 size_t read(uint8_t buf[], size_t len) override {
93 m_timer.expires_from_now(m_timeout);
94
95 boost::system::error_code ec = boost::asio::error::would_block;
96 size_t got = 0;
97
98 m_udp.async_receive(boost::asio::buffer(buf, len), [&](boost::system::error_code cb_ec, size_t cb_got) {
99 ec = cb_ec;
100 got = cb_got;
101 });
102
103 while(ec == boost::asio::error::would_block) {
104 m_io.run_one();
105 }
106
107 if(ec) {
108 if(ec == boost::asio::error::eof) {
109 return 0;
110 }
111 throw boost::system::system_error(ec); // Some other error.
112 }
113
114 return got;
115 }
116
117 private:
118 void check_timeout() {
119 if(m_udp.is_open() && m_timer.expires_at() < std::chrono::system_clock::now()) {
120 boost::system::error_code err;
121
122 // NOLINTNEXTLINE(bugprone-unused-return-value,cert-err33-c)
123 m_udp.close(err);
124 }
125
126 m_timer.async_wait(std::bind(&Asio_SocketUDP::check_timeout, this));
127 }
128
129 const std::chrono::microseconds m_timeout;
130 boost::asio::io_service m_io;
131 boost::asio::system_timer m_timer;
132 boost::asio::ip::udp::socket m_udp;
133};
134#elif defined(BOTAN_TARGET_OS_HAS_SOCKETS) || defined(BOTAN_TARGET_OS_HAS_WINSOCK2)
135class BSD_SocketUDP final : public OS::SocketUDP {
136 public:
137 BSD_SocketUDP(std::string_view hostname, std::string_view service, std::chrono::microseconds timeout) :
138 m_timeout(timeout) {
139 socket_init();
140
141 m_socket = invalid_socket();
142
143 addrinfo* res;
144 addrinfo hints;
145 clear_mem(&hints, 1);
146 hints.ai_family = AF_UNSPEC;
147 hints.ai_socktype = SOCK_DGRAM;
148
149 const std::string hostname_str(hostname);
150 const std::string service_str(service);
151
152 int rc = ::getaddrinfo(hostname_str.c_str(), service_str.c_str(), &hints, &res);
153
154 if(rc != 0) {
155 throw System_Error(fmt("Name resolution failed for {}", hostname), rc);
156 }
157
158 for(addrinfo* rp = res; (m_socket == invalid_socket()) && (rp != nullptr); rp = rp->ai_next) {
159 if(rp->ai_family != AF_INET && rp->ai_family != AF_INET6) {
160 continue;
161 }
162
163 m_socket = ::socket(rp->ai_family, rp->ai_socktype, rp->ai_protocol);
164
165 if(m_socket == invalid_socket()) [[unlikely]] {
166 // unsupported socket type?
167 continue;
168 }
169
170 set_nonblocking(m_socket);
171 memcpy(&sa, res->ai_addr, res->ai_addrlen);
172 salen = static_cast<socklen_t>(res->ai_addrlen);
173 }
174
175 ::freeaddrinfo(res);
176
177 if(m_socket == invalid_socket()) {
178 throw System_Error(fmt("Connecting to {} for service {} failed with errno {}", hostname, service, errno),
179 errno);
180 }
181 }
182
183 ~BSD_SocketUDP() override {
184 close_socket(m_socket);
185 m_socket = invalid_socket();
186 socket_fini();
187 }
188
189 BSD_SocketUDP(const BSD_SocketUDP& other) = delete;
190 BSD_SocketUDP(BSD_SocketUDP&& other) = delete;
191 BSD_SocketUDP& operator=(const BSD_SocketUDP& other) = delete;
192 BSD_SocketUDP& operator=(BSD_SocketUDP&& other) = delete;
193
194 void write(const uint8_t buf[], size_t len) override {
195 fd_set write_set;
196 FD_ZERO(&write_set);
197 FD_SET(m_socket, &write_set);
198
199 size_t sent_so_far = 0;
200 while(sent_so_far != len) {
201 struct timeval timeout = make_timeout_tv();
202 int active = ::select(static_cast<int>(m_socket + 1), nullptr, &write_set, nullptr, &timeout);
203
204 if(active == 0) {
205 throw System_Error("Timeout during socket write");
206 }
207
208 const size_t left = len - sent_so_far;
209 socket_op_ret_type sent = ::sendto(m_socket,
210 cast_uint8_ptr_to_char(buf + sent_so_far),
211 static_cast<sendrecv_len_type>(left),
212 0,
213 reinterpret_cast<sockaddr*>(&sa),
214 salen);
215 if(sent < 0) {
216 throw System_Error("Socket write failed", errno);
217 } else {
218 sent_so_far += static_cast<size_t>(sent);
219 }
220 }
221 }
222
223 size_t read(uint8_t buf[], size_t len) override {
224 fd_set read_set;
225 FD_ZERO(&read_set);
226 FD_SET(m_socket, &read_set);
227
228 struct timeval timeout = make_timeout_tv();
229 int active = ::select(static_cast<int>(m_socket + 1), &read_set, nullptr, nullptr, &timeout);
230
231 if(active == 0) {
232 throw System_Error("Timeout during socket read");
233 }
234
235 socket_op_ret_type got =
236 ::recvfrom(m_socket, cast_uint8_ptr_to_char(buf), static_cast<sendrecv_len_type>(len), 0, nullptr, nullptr);
237
238 if(got < 0) {
239 throw System_Error("Socket read failed", errno);
240 }
241
242 return static_cast<size_t>(got);
243 }
244
245 private:
246 #if defined(BOTAN_TARGET_OS_HAS_WINSOCK2)
247 typedef SOCKET socket_type;
248 typedef int socket_op_ret_type;
249 typedef int sendrecv_len_type;
250
251 static socket_type invalid_socket() { return INVALID_SOCKET; }
252
253 static void close_socket(socket_type s) { ::closesocket(s); }
254
255 static std::string get_last_socket_error() { return std::to_string(::WSAGetLastError()); }
256
257 static bool nonblocking_connect_in_progress() { return (::WSAGetLastError() == WSAEWOULDBLOCK); }
258
259 static void set_nonblocking(socket_type s) {
260 u_long nonblocking = 1;
261 ::ioctlsocket(s, FIONBIO, &nonblocking);
262 }
263
264 static void socket_init() {
265 WSAData wsa_data;
266 WORD wsa_version = MAKEWORD(2, 2);
267
268 if(::WSAStartup(wsa_version, &wsa_data) != 0) {
269 throw System_Error("WSAStartup() failed", WSAGetLastError());
270 }
271
272 if(LOBYTE(wsa_data.wVersion) != 2 || HIBYTE(wsa_data.wVersion) != 2) {
273 ::WSACleanup();
274 throw System_Error("Could not find a usable version of Winsock.dll");
275 }
276 }
277
278 static void socket_fini() { ::WSACleanup(); }
279 #else
280 typedef int socket_type;
281 typedef ssize_t socket_op_ret_type;
282 typedef size_t sendrecv_len_type;
283
284 static socket_type invalid_socket() { return -1; }
285
286 static void close_socket(socket_type s) { ::close(s); }
287
288 static std::string get_last_socket_error() { return ::strerror(errno); }
289
290 static bool nonblocking_connect_in_progress() { return (errno == EINPROGRESS); }
291
292 static void set_nonblocking(socket_type s) {
293 if(::fcntl(s, F_SETFL, O_NONBLOCK) < 0) {
294 throw System_Error("Setting socket to non-blocking state failed", errno);
295 }
296 }
297
298 static void socket_init() {}
299
300 static void socket_fini() {}
301 #endif
302 sockaddr_storage sa;
303 socklen_t salen;
304
305 struct timeval make_timeout_tv() const {
306 struct timeval tv;
307 tv.tv_sec = static_cast<decltype(timeval::tv_sec)>(m_timeout.count() / 1000000);
308 tv.tv_usec = static_cast<decltype(timeval::tv_usec)>(m_timeout.count() % 1000000);
309 return tv;
310 }
311
312 const std::chrono::microseconds m_timeout;
313 socket_type m_socket;
314};
315#endif
316} // namespace
317
318std::unique_ptr<OS::SocketUDP> OS::open_socket_udp(std::string_view hostname,
319 std::string_view service,
320 std::chrono::microseconds timeout) {
321#if defined(BOTAN_HAS_BOOST_ASIO)
322 return std::make_unique<Asio_SocketUDP>(hostname, service, timeout);
323#elif defined(BOTAN_TARGET_OS_HAS_SOCKETS) || defined(BOTAN_TARGET_OS_HAS_WINSOCK2)
324 return std::make_unique<BSD_SocketUDP>(hostname, service, timeout);
325#else
326 BOTAN_UNUSED(hostname);
327 BOTAN_UNUSED(service);
328 BOTAN_UNUSED(timeout);
329 return std::unique_ptr<OS::SocketUDP>();
330#endif
331}
332
333std::unique_ptr<OS::SocketUDP> OS::open_socket_udp(std::string_view uri_string, std::chrono::microseconds timeout) {
334 const auto uri = URI::fromAny(uri_string);
335 if(uri.port == 0) {
336 throw Invalid_Argument("UDP port not specified");
337 }
338 return open_socket_udp(uri.host, std::to_string(uri.port), timeout);
339}
340
341} // namespace Botan
#define BOTAN_UNUSED
Definition assert.h:118
int(* final)(unsigned char *, CTX *)
std::unique_ptr< SocketUDP > BOTAN_TEST_API open_socket_udp(std::string_view hostname, std::string_view service, std::chrono::microseconds timeout)
std::string fmt(std::string_view format, const T &... args)
Definition fmt.h:53
static URI fromAny(std::string_view uri)
Definition uri.cpp:183