apps/lib/s_socket.c

   1 /*
   2  * Copyright 1995-2021 The OpenSSL Project Authors. All Rights Reserved.
   3  *
   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
   8  */
   9
  10 /* socket-related functions used by s_client and s_server */
  11 #include <stdio.h>
  12 #include <stdlib.h>
  13 #include <string.h>
  14 #include <errno.h>
  15 #include <signal.h>
  16 #include <openssl/opensslconf.h>
  17
  18 /*
  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
  23  */
  24 #if defined(OPENSSL_SYS_VMS_DECC) && !defined(__U_INT)
  25 # define __U_INT
  26 typedef unsigned int u_int;
  27 #endif
  28
  29 #ifdef _WIN32
  30 /*
  31  * With MSVC, certain POSIX functions have been renamed to have an underscore
  32  * prefix.
  33  */
  34 # include <process.h>
  35 # define getpid _getpid
  36 #endif
  37
  38 #ifndef OPENSSL_NO_SOCK
  39
  40 # include "apps.h"
  41 # include "s_apps.h"
  42 # include "internal/sockets.h"
  43
  44 # if defined(__TANDEM)
  45 #  if defined(OPENSSL_TANDEM_FLOSS)
  46 #   include <floss.h(floss_read)>
  47 #  endif
  48 # endif
  49
  50 # include <openssl/bio.h>
  51 # include <openssl/err.h>
  52
  53 /* Keep track of our peer's address for the cookie callback */
  54 BIO_ADDR *ourpeer = NULL;
  55
  56 /*
  57  * init_client - helper routine to set up socket communication
  58  * @sock: pointer to storage of resulting socket.
  59  * @host: the host name or path (for AF_UNIX) to connect to.
  60  * @port: the port to connect to (ignored for AF_UNIX).
  61  * @bindhost: source host or path (for AF_UNIX).
  62  * @bindport: source port (ignored for AF_UNIX).
  63  * @family: desired socket family, may be AF_INET, AF_INET6, AF_UNIX or
  64  *  AF_UNSPEC
  65  * @type: socket type, must be SOCK_STREAM or SOCK_DGRAM
  66  * @protocol: socket protocol, e.g. IPPROTO_TCP or IPPROTO_UDP (or 0 for any)
  67  *
  68  * This will create a socket and use it to connect to a host:port, or if
  69  * family == AF_UNIX, to the path found in host.
  70  *
  71  * If the host has more than one address, it will try them one by one until
  72  * a successful connection is established.  The resulting socket will be
  73  * found in *sock on success, it will be given INVALID_SOCKET otherwise.
  74  *
  75  * Returns 1 on success, 0 on failure.
  76  */
  77 int init_client(int *sock, const char *host, const char *port,
  78                 const char *bindhost, const char *bindport,
  79                 int family, int type, int protocol)
  80 {
  81     BIO_ADDRINFO *res = NULL;
  82     BIO_ADDRINFO *bindaddr = NULL;
  83     const BIO_ADDRINFO *ai = NULL;
  84     const BIO_ADDRINFO *bi = NULL;
  85     int found = 0;
  86     int ret;
  87
  88     if (BIO_sock_init() != 1)
  89         return 0;
  90
  91     ret = BIO_lookup_ex(host, port, BIO_LOOKUP_CLIENT, family, type, protocol,
  92                         &res);
  93     if (ret == 0) {
  94         ERR_print_errors(bio_err);
  95         return 0;
  96     }
  97
  98     if (bindhost != NULL || bindport != NULL) {
  99         ret = BIO_lookup_ex(bindhost, bindport, BIO_LOOKUP_CLIENT,
 100                             family, type, protocol, &bindaddr);
 101         if (ret == 0) {
 102             ERR_print_errors (bio_err);
 103             goto out;
 104         }
 105     }
 106
 107     ret = 0;
 108     for (ai = res; ai != NULL; ai = BIO_ADDRINFO_next(ai)) {
 109         /* Admittedly, these checks are quite paranoid, we should not get
 110          * anything in the BIO_ADDRINFO chain that we haven't
 111          * asked for. */
 112         OPENSSL_assert((family == AF_UNSPEC
 113                         || family == BIO_ADDRINFO_family(ai))
 114                        && (type == 0 || type == BIO_ADDRINFO_socktype(ai))
 115                        && (protocol == 0
 116                            || protocol == BIO_ADDRINFO_protocol(ai)));
 117
 118         if (bindaddr != NULL) {
 119             for (bi = bindaddr; bi != NULL; bi = BIO_ADDRINFO_next(bi)) {
 120                 if (BIO_ADDRINFO_family(bi) == BIO_ADDRINFO_family(ai))
 121                     break;
 122             }
 123             if (bi == NULL)
 124                 continue;
 125             ++found;
 126         }
 127
 128         *sock = BIO_socket(BIO_ADDRINFO_family(ai), BIO_ADDRINFO_socktype(ai),
 129                            BIO_ADDRINFO_protocol(ai), 0);
 130         if (*sock == INVALID_SOCKET) {
 131             /* Maybe the kernel doesn't support the socket family, even if
 132              * BIO_lookup() added it in the returned result...
 133              */
 134             continue;
 135         }
 136
 137         if (bi != NULL) {
 138             if (!BIO_bind(*sock, BIO_ADDRINFO_address(bi),
 139                           BIO_SOCK_REUSEADDR)) {
 140                 BIO_closesocket(*sock);
 141                 *sock = INVALID_SOCKET;
 142                 break;
 143             }
 144         }
 145
 146 #ifndef OPENSSL_NO_SCTP
 147         if (protocol == IPPROTO_SCTP) {
 148             /*
 149              * For SCTP we have to set various options on the socket prior to
 150              * connecting. This is done automatically by BIO_new_dgram_sctp().
 151              * We don't actually need the created BIO though so we free it again
 152              * immediately.
 153              */
 154             BIO *tmpbio = BIO_new_dgram_sctp(*sock, BIO_NOCLOSE);
 155
 156             if (tmpbio == NULL) {
 157                 ERR_print_errors(bio_err);
 158                 return 0;
 159             }
 160             BIO_free(tmpbio);
 161         }
 162 #endif
 163
 164         if (!BIO_connect(*sock, BIO_ADDRINFO_address(ai),
 165                          protocol == IPPROTO_TCP ? BIO_SOCK_NODELAY : 0)) {
 166             BIO_closesocket(*sock);
 167             *sock = INVALID_SOCKET;
 168             continue;
 169         }
 170
 171         /* Success, don't try any more addresses */
 172         break;
 173     }
 174
 175     if (*sock == INVALID_SOCKET) {
 176         if (bindaddr != NULL && !found) {
 177             BIO_printf(bio_err, "Can't bind %saddress for %s%s%s\n",
 178 #ifdef AF_INET6
 179                        BIO_ADDRINFO_family(res) == AF_INET6 ? "IPv6 " :
 180 #endif
 181                        BIO_ADDRINFO_family(res) == AF_INET ? "IPv4 " :
 182                        BIO_ADDRINFO_family(res) == AF_UNIX ? "unix " : "",
 183                        bindhost != NULL ? bindhost : "",
 184                        bindport != NULL ? ":" : "",
 185                        bindport != NULL ? bindport : "");
 186             ERR_clear_error();
 187             ret = 0;
 188         }
 189         ERR_print_errors(bio_err);
 190     } else {
 191         /* Remove any stale errors from previous connection attempts */
 192         ERR_clear_error();
 193         ret = 1;
 194     }
 195 out:
 196     if (bindaddr != NULL) {
 197         BIO_ADDRINFO_free (bindaddr);
 198     }
 199     BIO_ADDRINFO_free(res);
 200     return ret;
 201 }
 202
 203 int report_server_accept(BIO *out, int asock, int with_address, int with_pid)
 204 {
 205     int success = 1;
 206
 207     if (BIO_printf(out, "ACCEPT") <= 0)
 208         return 0;
 209     if (with_address) {
 210         union BIO_sock_info_u info;
 211         char *hostname = NULL;
 212         char *service = NULL;
 213
 214         if ((info.addr = BIO_ADDR_new()) != NULL
 215             && BIO_sock_info(asock, BIO_SOCK_INFO_ADDRESS, &info)
 216             && (hostname = BIO_ADDR_hostname_string(info.addr, 1)) != NULL
 217             && (service = BIO_ADDR_service_string(info.addr, 1)) != NULL) {
 218             success = BIO_printf(out,
 219                                  strchr(hostname, ':') == NULL
 220                                  ? /* IPv4 */ " %s:%s"
 221                                  : /* IPv6 */ " [%s]:%s",
 222                                  hostname, service) > 0;
 223         } else {
 224             (void)BIO_printf(out, "unknown:error\n");
 225             success = 0;
 226         }
 227         OPENSSL_free(hostname);
 228         OPENSSL_free(service);
 229         BIO_ADDR_free(info.addr);
 230     }
 231     if (with_pid)
 232         success = success && BIO_printf(out, " PID=%d", getpid()) > 0;
 233     success = success && BIO_printf(out, "\n") > 0;
 234     (void)BIO_flush(out);
 235
 236     return success;
 237 }
 238
 239 /*
 240  * do_server - helper routine to perform a server operation
 241  * @accept_sock: pointer to storage of resulting socket.
 242  * @host: the host name or path (for AF_UNIX) to connect to.
 243  * @port: the port to connect to (ignored for AF_UNIX).
 244  * @family: desired socket family, may be AF_INET, AF_INET6, AF_UNIX or
 245  *  AF_UNSPEC
 246  * @type: socket type, must be SOCK_STREAM or SOCK_DGRAM
 247  * @cb: pointer to a function that receives the accepted socket and
 248  *  should perform the communication with the connecting client.
 249  * @context: pointer to memory that's passed verbatim to the cb function.
 250  * @naccept: number of times an incoming connect should be accepted.  If -1,
 251  *  unlimited number.
 252  *
 253  * This will create a socket and use it to listen to a host:port, or if
 254  * family == AF_UNIX, to the path found in host, then start accepting
 255  * incoming connections and run cb on the resulting socket.
 256  *
 257  * 0 on failure, something other on success.
 258  */
 259 int do_server(int *accept_sock, const char *host, const char *port,
 260               int family, int type, int protocol, do_server_cb cb,
 261               unsigned char *context, int naccept, BIO *bio_s_out)
 262 {
 263     int asock = 0;
 264     int sock;
 265     int i;
 266     BIO_ADDRINFO *res = NULL;
 267     const BIO_ADDRINFO *next;
 268     int sock_family, sock_type, sock_protocol, sock_port;
 269     const BIO_ADDR *sock_address;
 270     int sock_options = BIO_SOCK_REUSEADDR;
 271     int ret = 0;
 272
 273     if (BIO_sock_init() != 1)
 274         return 0;
 275
 276     if (!BIO_lookup_ex(host, port, BIO_LOOKUP_SERVER, family, type, protocol,
 277                        &res)) {
 278         ERR_print_errors(bio_err);
 279         return 0;
 280     }
 281
 282     /* Admittedly, these checks are quite paranoid, we should not get
 283      * anything in the BIO_ADDRINFO chain that we haven't asked for */
 284     OPENSSL_assert((family == AF_UNSPEC || family == BIO_ADDRINFO_family(res))
 285                    && (type == 0 || type == BIO_ADDRINFO_socktype(res))
 286                    && (protocol == 0 || protocol == BIO_ADDRINFO_protocol(res)));
 287
 288     sock_family = BIO_ADDRINFO_family(res);
 289     sock_type = BIO_ADDRINFO_socktype(res);
 290     sock_protocol = BIO_ADDRINFO_protocol(res);
 291     sock_address = BIO_ADDRINFO_address(res);
 292     next = BIO_ADDRINFO_next(res);
 293 #ifdef AF_INET6
 294     if (sock_family == AF_INET6)
 295         sock_options |= BIO_SOCK_V6_ONLY;
 296     if (next != NULL
 297             && BIO_ADDRINFO_socktype(next) == sock_type
 298             && BIO_ADDRINFO_protocol(next) == sock_protocol) {
 299         if (sock_family == AF_INET
 300                 && BIO_ADDRINFO_family(next) == AF_INET6) {
 301             sock_family = AF_INET6;
 302             sock_address = BIO_ADDRINFO_address(next);
 303         } else if (sock_family == AF_INET6
 304                    && BIO_ADDRINFO_family(next) == AF_INET) {
 305             sock_options &= ~BIO_SOCK_V6_ONLY;
 306         }
 307     }
 308 #endif
 309
 310     asock = BIO_socket(sock_family, sock_type, sock_protocol, 0);
 311     if (asock == INVALID_SOCKET
 312         || !BIO_listen(asock, sock_address, sock_options)) {
 313         BIO_ADDRINFO_free(res);
 314         ERR_print_errors(bio_err);
 315         if (asock != INVALID_SOCKET)
 316             BIO_closesocket(asock);
 317         goto end;
 318     }
 319
 320 #ifndef OPENSSL_NO_SCTP
 321     if (protocol == IPPROTO_SCTP) {
 322         /*
 323          * For SCTP we have to set various options on the socket prior to
 324          * accepting. This is done automatically by BIO_new_dgram_sctp().
 325          * We don't actually need the created BIO though so we free it again
 326          * immediately.
 327          */
 328         BIO *tmpbio = BIO_new_dgram_sctp(asock, BIO_NOCLOSE);
 329
 330         if (tmpbio == NULL) {
 331             BIO_closesocket(asock);
 332             ERR_print_errors(bio_err);
 333             goto end;
 334         }
 335         BIO_free(tmpbio);
 336     }
 337 #endif
 338
 339     sock_port = BIO_ADDR_rawport(sock_address);
 340
 341     BIO_ADDRINFO_free(res);
 342     res = NULL;
 343
 344     if (!report_server_accept(bio_s_out, asock, sock_port == 0, 0)) {
 345         BIO_closesocket(asock);
 346         ERR_print_errors(bio_err);
 347         goto end;
 348     }
 349
 350     if (accept_sock != NULL)
 351         *accept_sock = asock;
 352     for (;;) {
 353         char sink[64];
 354         struct timeval timeout;
 355         fd_set readfds;
 356
 357         if (type == SOCK_STREAM) {
 358             BIO_ADDR_free(ourpeer);
 359             ourpeer = BIO_ADDR_new();
 360             if (ourpeer == NULL) {
 361                 BIO_closesocket(asock);
 362                 ERR_print_errors(bio_err);
 363                 goto end;
 364             }
 365             do {
 366                 sock = BIO_accept_ex(asock, ourpeer, 0);
 367             } while (sock < 0 && BIO_sock_should_retry(sock));
 368             if (sock < 0) {
 369                 ERR_print_errors(bio_err);
 370                 BIO_closesocket(asock);
 371                 break;
 372             }
 373             BIO_set_tcp_ndelay(sock, 1);
 374             i = (*cb)(sock, type, protocol, context);
 375
 376             /*
 377              * If we ended with an alert being sent, but still with data in the
 378              * network buffer to be read, then calling BIO_closesocket() will
 379              * result in a TCP-RST being sent. On some platforms (notably
 380              * Windows) then this will result in the peer immediately abandoning
 381              * the connection including any buffered alert data before it has
 382              * had a chance to be read. Shutting down the sending side first,
 383              * and then closing the socket sends TCP-FIN first followed by
 384              * TCP-RST. This seems to allow the peer to read the alert data.
 385              */
 386             shutdown(sock, 1); /* SHUT_WR */
 387             /*
 388              * We just said we have nothing else to say, but it doesn't mean
 389              * that the other side has nothing. It's even recommended to
 390              * consume incoming data. [In testing context this ensures that
 391              * alerts are passed on...]
 392              */
 393             timeout.tv_sec = 0;
 394             timeout.tv_usec = 500000;  /* some extreme round-trip */
 395             do {
 396                 FD_ZERO(&readfds);
 397                 openssl_fdset(sock, &readfds);
 398             } while (select(sock + 1, &readfds, NULL, NULL, &timeout) > 0
 399                      && readsocket(sock, sink, sizeof(sink)) > 0);
 400
 401             BIO_closesocket(sock);
 402         } else {
 403             i = (*cb)(asock, type, protocol, context);
 404         }
 405
 406         if (naccept != -1)
 407             naccept--;
 408         if (i < 0 || naccept == 0) {
 409             BIO_closesocket(asock);
 410             ret = i;
 411             break;
 412         }
 413     }
 414  end:
 415 # ifdef AF_UNIX
 416     if (family == AF_UNIX)
 417         unlink(host);
 418 # endif
 419     BIO_ADDR_free(ourpeer);
 420     ourpeer = NULL;
 421     return ret;
 422 }
 423
 424 void do_ssl_shutdown(SSL *ssl)
 425 {
 426     int ret;
 427
 428     do {
 429         /* We only do unidirectional shutdown */
 430         ret = SSL_shutdown(ssl);
 431         if (ret < 0) {
 432             switch (SSL_get_error(ssl, ret)) {
 433             case SSL_ERROR_WANT_READ:
 434             case SSL_ERROR_WANT_WRITE:
 435             case SSL_ERROR_WANT_ASYNC:
 436             case SSL_ERROR_WANT_ASYNC_JOB:
 437                 /* We just do busy waiting. Nothing clever */
 438                 continue;
 439             }
 440             ret = 0;
 441         }
 442     } while (ret < 0);
 443 }
 444
 445 #endif  /* OPENSSL_NO_SOCK */