2 * Copyright 1995-2023 The OpenSSL Project Authors. All Rights Reserved.
4 * Licensed under the Apache License 2.0 (the "License"). You may not use
5 * this file except in compliance with the License. You can obtain a copy
6 * in the file LICENSE in the source distribution or at
7 * https://www.openssl.org/source/license.html
10 /* socket-related functions used by s_client and s_server */
16 #include <openssl/opensslconf.h>
19 * With IPv6, it looks like Digital has mixed up the proper order of
20 * recursive header file inclusion, resulting in the compiler complaining
21 * that u_int isn't defined, but only if _POSIX_C_SOURCE is defined, which is
22 * needed to have fileno() declared correctly... So let's define u_int
24 #if defined(OPENSSL_SYS_VMS_DECC) && !defined(__U_INT)
26 typedef unsigned int u_int;
32 /* MSVC renamed some POSIX functions to have an underscore prefix. */
34 # define getpid _getpid
38 #ifndef OPENSSL_NO_SOCK
42 # include "internal/sockets.h"
44 # include <openssl/bio.h>
45 # include <openssl/err.h>
47 /* Keep track of our peer's address for the cookie callback */
48 BIO_ADDR *ourpeer = NULL;
51 * init_client - helper routine to set up socket communication
52 * @sock: pointer to storage of resulting socket.
53 * @host: the hostname or path (for AF_UNIX) to connect to.
54 * @port: the port to connect to (ignored for AF_UNIX).
55 * @bindhost: source host or path (for AF_UNIX).
56 * @bindport: source port (ignored for AF_UNIX).
57 * @family: desired socket family, may be AF_INET, AF_INET6, AF_UNIX or
59 * @type: socket type, must be SOCK_STREAM or SOCK_DGRAM
60 * @protocol: socket protocol, e.g. IPPROTO_TCP or IPPROTO_UDP (or 0 for any)
61 * @tfo: flag to enable TCP Fast Open
62 * @doconn: whether we should call BIO_connect() on the socket
63 * @ba_ret: BIO_ADDR for the remote peer, to be freed by caller
65 * This will create a socket and use it to connect to a host:port, or if
66 * family == AF_UNIX, to the path found in host.
68 * If the host has more than one address, it will try them one by one until
69 * a successful connection is established. The resulting socket will be
70 * found in *sock on success, it will be given INVALID_SOCKET otherwise.
72 * Returns 1 on success, 0 on failure.
74 int init_client(int *sock, const char *host, const char *port,
75 const char *bindhost, const char *bindport,
76 int family, int type, int protocol, int tfo, int doconn,
79 BIO_ADDRINFO *res = NULL;
80 BIO_ADDRINFO *bindaddr = NULL;
81 const BIO_ADDRINFO *ai = NULL;
82 const BIO_ADDRINFO *bi = NULL;
87 if (tfo && ba_ret != NULL)
90 if (BIO_sock_init() != 1)
93 ret = BIO_lookup_ex(host, port, BIO_LOOKUP_CLIENT, family, type, protocol,
96 ERR_print_errors(bio_err);
100 if (bindhost != NULL || bindport != NULL) {
101 ret = BIO_lookup_ex(bindhost, bindport, BIO_LOOKUP_CLIENT,
102 family, type, protocol, &bindaddr);
104 ERR_print_errors (bio_err);
110 for (ai = res; ai != NULL; ai = BIO_ADDRINFO_next(ai)) {
111 /* Admittedly, these checks are quite paranoid, we should not get
112 * anything in the BIO_ADDRINFO chain that we haven't
114 OPENSSL_assert((family == AF_UNSPEC
115 || family == BIO_ADDRINFO_family(ai))
116 && (type == 0 || type == BIO_ADDRINFO_socktype(ai))
118 || protocol == BIO_ADDRINFO_protocol(ai)));
120 if (bindaddr != NULL) {
121 for (bi = bindaddr; bi != NULL; bi = BIO_ADDRINFO_next(bi)) {
122 if (BIO_ADDRINFO_family(bi) == BIO_ADDRINFO_family(ai))
130 *sock = BIO_socket(BIO_ADDRINFO_family(ai), BIO_ADDRINFO_socktype(ai),
131 BIO_ADDRINFO_protocol(ai), 0);
132 if (*sock == INVALID_SOCKET) {
133 /* Maybe the kernel doesn't support the socket family, even if
134 * BIO_lookup() added it in the returned result...
140 if (!BIO_bind(*sock, BIO_ADDRINFO_address(bi),
141 BIO_SOCK_REUSEADDR)) {
142 BIO_closesocket(*sock);
143 *sock = INVALID_SOCKET;
148 #ifndef OPENSSL_NO_SCTP
149 if (protocol == IPPROTO_SCTP) {
151 * For SCTP we have to set various options on the socket prior to
152 * connecting. This is done automatically by BIO_new_dgram_sctp().
153 * We don't actually need the created BIO though so we free it again
156 BIO *tmpbio = BIO_new_dgram_sctp(*sock, BIO_NOCLOSE);
158 if (tmpbio == NULL) {
159 ERR_print_errors(bio_err);
165 if (BIO_ADDRINFO_protocol(ai) == IPPROTO_TCP) {
166 options |= BIO_SOCK_NODELAY;
168 options |= BIO_SOCK_TFO;
171 if (doconn && !BIO_connect(*sock, BIO_ADDRINFO_address(ai), options)) {
172 BIO_closesocket(*sock);
173 *sock = INVALID_SOCKET;
177 /* Save the address */
179 *ba_ret = BIO_ADDR_dup(BIO_ADDRINFO_address(ai));
181 /* Success, don't try any more addresses */
185 if (*sock == INVALID_SOCKET) {
186 if (bindaddr != NULL && !found) {
187 BIO_printf(bio_err, "Can't bind %saddress for %s%s%s\n",
189 BIO_ADDRINFO_family(res) == AF_INET6 ? "IPv6 " :
191 BIO_ADDRINFO_family(res) == AF_INET ? "IPv4 " :
192 BIO_ADDRINFO_family(res) == AF_UNIX ? "unix " : "",
193 bindhost != NULL ? bindhost : "",
194 bindport != NULL ? ":" : "",
195 bindport != NULL ? bindport : "");
199 ERR_print_errors(bio_err);
201 char *hostname = NULL;
203 hostname = BIO_ADDR_hostname_string(BIO_ADDRINFO_address(ai), 1);
204 if (hostname != NULL) {
205 BIO_printf(bio_err, "Connecting to %s\n", hostname);
206 OPENSSL_free(hostname);
208 /* Remove any stale errors from previous connection attempts */
213 if (bindaddr != NULL) {
214 BIO_ADDRINFO_free (bindaddr);
216 BIO_ADDRINFO_free(res);
220 void get_sock_info_address(int asock, char **hostname, char **service)
222 union BIO_sock_info_u info;
224 if (hostname != NULL)
229 if ((info.addr = BIO_ADDR_new()) != NULL
230 && BIO_sock_info(asock, BIO_SOCK_INFO_ADDRESS, &info)) {
231 if (hostname != NULL)
232 *hostname = BIO_ADDR_hostname_string(info.addr, 1);
234 *service = BIO_ADDR_service_string(info.addr, 1);
236 BIO_ADDR_free(info.addr);
239 int report_server_accept(BIO *out, int asock, int with_address, int with_pid)
243 if (BIO_printf(out, "ACCEPT") <= 0)
246 char *hostname, *service;
248 get_sock_info_address(asock, &hostname, &service);
249 success = hostname != NULL && service != NULL;
251 success = BIO_printf(out,
252 strchr(hostname, ':') == NULL
253 ? /* IPv4 */ " %s:%s"
254 : /* IPv6 */ " [%s]:%s",
255 hostname, service) > 0;
257 (void)BIO_printf(out, "unknown:error\n");
258 OPENSSL_free(hostname);
259 OPENSSL_free(service);
262 success *= BIO_printf(out, " PID=%d", getpid()) > 0;
263 success *= BIO_printf(out, "\n") > 0;
264 (void)BIO_flush(out);
270 * do_server - helper routine to perform a server operation
271 * @accept_sock: pointer to storage of resulting socket.
272 * @host: the hostname or path (for AF_UNIX) to connect to.
273 * @port: the port to connect to (ignored for AF_UNIX).
274 * @family: desired socket family, may be AF_INET, AF_INET6, AF_UNIX or
276 * @type: socket type, must be SOCK_STREAM or SOCK_DGRAM
277 * @cb: pointer to a function that receives the accepted socket and
278 * should perform the communication with the connecting client.
279 * @context: pointer to memory that's passed verbatim to the cb function.
280 * @naccept: number of times an incoming connect should be accepted. If -1,
283 * This will create a socket and use it to listen to a host:port, or if
284 * family == AF_UNIX, to the path found in host, then start accepting
285 * incoming connections and run cb on the resulting socket.
287 * 0 on failure, something other on success.
289 int do_server(int *accept_sock, const char *host, const char *port,
290 int family, int type, int protocol, do_server_cb cb,
291 unsigned char *context, int naccept, BIO *bio_s_out,
297 BIO_ADDRINFO *res = NULL;
298 const BIO_ADDRINFO *next;
299 int sock_family, sock_type, sock_protocol, sock_port;
300 const BIO_ADDR *sock_address;
301 int sock_family_fallback = AF_UNSPEC;
302 const BIO_ADDR *sock_address_fallback = NULL;
303 int sock_options = BIO_SOCK_REUSEADDR;
306 if (BIO_sock_init() != 1)
309 if (!BIO_lookup_ex(host, port, BIO_LOOKUP_SERVER, family, type, protocol,
311 ERR_print_errors(bio_err);
315 /* Admittedly, these checks are quite paranoid, we should not get
316 * anything in the BIO_ADDRINFO chain that we haven't asked for */
317 OPENSSL_assert((family == AF_UNSPEC || family == BIO_ADDRINFO_family(res))
318 && (type == 0 || type == BIO_ADDRINFO_socktype(res))
319 && (protocol == 0 || protocol == BIO_ADDRINFO_protocol(res)));
321 sock_family = BIO_ADDRINFO_family(res);
322 sock_type = BIO_ADDRINFO_socktype(res);
323 sock_protocol = BIO_ADDRINFO_protocol(res);
324 sock_address = BIO_ADDRINFO_address(res);
325 next = BIO_ADDRINFO_next(res);
326 if (tfo && sock_type == SOCK_STREAM)
327 sock_options |= BIO_SOCK_TFO;
329 if (sock_family == AF_INET6)
330 sock_options |= BIO_SOCK_V6_ONLY;
332 && BIO_ADDRINFO_socktype(next) == sock_type
333 && BIO_ADDRINFO_protocol(next) == sock_protocol) {
334 if (sock_family == AF_INET
335 && BIO_ADDRINFO_family(next) == AF_INET6) {
336 /* In case AF_INET6 is returned but not supported by the
337 * kernel, retry with the first detected address family */
338 sock_family_fallback = sock_family;
339 sock_address_fallback = sock_address;
340 sock_family = AF_INET6;
341 sock_address = BIO_ADDRINFO_address(next);
342 } else if (sock_family == AF_INET6
343 && BIO_ADDRINFO_family(next) == AF_INET) {
344 sock_options &= ~BIO_SOCK_V6_ONLY;
349 asock = BIO_socket(sock_family, sock_type, sock_protocol, 0);
350 if (asock == INVALID_SOCKET && sock_family_fallback != AF_UNSPEC) {
351 asock = BIO_socket(sock_family_fallback, sock_type, sock_protocol, 0);
352 sock_address = sock_address_fallback;
354 if (asock == INVALID_SOCKET
355 || !BIO_listen(asock, sock_address, sock_options)) {
356 BIO_ADDRINFO_free(res);
357 ERR_print_errors(bio_err);
358 if (asock != INVALID_SOCKET)
359 BIO_closesocket(asock);
363 #ifndef OPENSSL_NO_SCTP
364 if (protocol == IPPROTO_SCTP) {
366 * For SCTP we have to set various options on the socket prior to
367 * accepting. This is done automatically by BIO_new_dgram_sctp().
368 * We don't actually need the created BIO though so we free it again
371 BIO *tmpbio = BIO_new_dgram_sctp(asock, BIO_NOCLOSE);
373 if (tmpbio == NULL) {
374 BIO_closesocket(asock);
375 ERR_print_errors(bio_err);
382 sock_port = BIO_ADDR_rawport(sock_address);
384 BIO_ADDRINFO_free(res);
387 if (!report_server_accept(bio_s_out, asock, sock_port == 0, 0)) {
388 BIO_closesocket(asock);
389 ERR_print_errors(bio_err);
393 if (accept_sock != NULL)
394 *accept_sock = asock;
397 struct timeval timeout;
400 if (type == SOCK_STREAM) {
401 BIO_ADDR_free(ourpeer);
402 ourpeer = BIO_ADDR_new();
403 if (ourpeer == NULL) {
404 BIO_closesocket(asock);
405 ERR_print_errors(bio_err);
409 sock = BIO_accept_ex(asock, ourpeer, 0);
410 } while (sock < 0 && BIO_sock_should_retry(sock));
412 ERR_print_errors(bio_err);
413 BIO_closesocket(asock);
416 BIO_set_tcp_ndelay(sock, 1);
417 i = (*cb)(sock, type, protocol, context);
420 * If we ended with an alert being sent, but still with data in the
421 * network buffer to be read, then calling BIO_closesocket() will
422 * result in a TCP-RST being sent. On some platforms (notably
423 * Windows) then this will result in the peer immediately abandoning
424 * the connection including any buffered alert data before it has
425 * had a chance to be read. Shutting down the sending side first,
426 * and then closing the socket sends TCP-FIN first followed by
427 * TCP-RST. This seems to allow the peer to read the alert data.
429 shutdown(sock, 1); /* SHUT_WR */
431 * We just said we have nothing else to say, but it doesn't mean
432 * that the other side has nothing. It's even recommended to
433 * consume incoming data. [In testing context this ensures that
434 * alerts are passed on...]
437 timeout.tv_usec = 500000; /* some extreme round-trip */
440 openssl_fdset(sock, &readfds);
441 } while (select(sock + 1, &readfds, NULL, NULL, &timeout) > 0
442 && readsocket(sock, sink, sizeof(sink)) > 0);
444 BIO_closesocket(sock);
446 i = (*cb)(asock, type, protocol, context);
451 if (i < 0 || naccept == 0) {
452 BIO_closesocket(asock);
459 if (family == AF_UNIX)
462 BIO_ADDR_free(ourpeer);
467 void do_ssl_shutdown(SSL *ssl)
472 /* We only do unidirectional shutdown */
473 ret = SSL_shutdown(ssl);
475 switch (SSL_get_error(ssl, ret)) {
476 case SSL_ERROR_WANT_READ:
477 case SSL_ERROR_WANT_WRITE:
478 case SSL_ERROR_WANT_ASYNC:
479 case SSL_ERROR_WANT_ASYNC_JOB:
480 /* We just do busy waiting. Nothing clever */
488 #endif /* OPENSSL_NO_SOCK */