crypto/bio/bss_dgram.c

   1 /* crypto/bio/bio_dgram.c */
   2 /*
   3  * DTLS implementation written by Nagendra Modadugu
   4  * (nagendra@cs.stanford.edu) for the OpenSSL project 2005.
   5  */
   6 /* ====================================================================
   7  * Copyright (c) 1999-2005 The OpenSSL Project.  All rights reserved.
   8  *
   9  * Redistribution and use in source and binary forms, with or without
  10  * modification, are permitted provided that the following conditions
  11  * are met:
  12  *
  13  * 1. Redistributions of source code must retain the above copyright
  14  *    notice, this list of conditions and the following disclaimer.
  15  *
  16  * 2. Redistributions in binary form must reproduce the above copyright
  17  *    notice, this list of conditions and the following disclaimer in
  18  *    the documentation and/or other materials provided with the
  19  *    distribution.
  20  *
  21  * 3. All advertising materials mentioning features or use of this
  22  *    software must display the following acknowledgment:
  23  *    "This product includes software developed by the OpenSSL Project
  24  *    for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
  25  *
  26  * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
  27  *    endorse or promote products derived from this software without
  28  *    prior written permission. For written permission, please contact
  29  *    openssl-core@OpenSSL.org.
  30  *
  31  * 5. Products derived from this software may not be called "OpenSSL"
  32  *    nor may "OpenSSL" appear in their names without prior written
  33  *    permission of the OpenSSL Project.
  34  *
  35  * 6. Redistributions of any form whatsoever must retain the following
  36  *    acknowledgment:
  37  *    "This product includes software developed by the OpenSSL Project
  38  *    for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
  39  *
  40  * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
  41  * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  42  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  43  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
  44  * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  45  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  46  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  47  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  48  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
  49  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  50  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
  51  * OF THE POSSIBILITY OF SUCH DAMAGE.
  52  * ====================================================================
  53  *
  54  * This product includes cryptographic software written by Eric Young
  55  * (eay@cryptsoft.com).  This product includes software written by Tim
  56  * Hudson (tjh@cryptsoft.com).
  57  *
  58  */
  59
  60 #ifndef OPENSSL_NO_DGRAM
  61
  62 #include <stdio.h>
  63 #include <errno.h>
  64 #define USE_SOCKETS
  65 #include "cryptlib.h"
  66
  67 #include <openssl/bio.h>
  68
  69 #if defined(OPENSSL_SYS_WIN32) || defined(OPENSSL_SYS_VMS)
  70 #include <sys/timeb.h>
  71 #endif
  72
  73 #ifdef OPENSSL_SYS_LINUX
  74 #define IP_MTU      14 /* linux is lame */
  75 #endif
  76
  77 #ifdef WATT32
  78 #define sock_write SockWrite  /* Watt-32 uses same names */
  79 #define sock_read  SockRead
  80 #define sock_puts  SockPuts
  81 #endif
  82
  83 static int dgram_write(BIO *h, const char *buf, int num);
  84 static int dgram_read(BIO *h, char *buf, int size);
  85 static int dgram_puts(BIO *h, const char *str);
  86 static long dgram_ctrl(BIO *h, int cmd, long arg1, void *arg2);
  87 static int dgram_new(BIO *h);
  88 static int dgram_free(BIO *data);
  89 static int dgram_clear(BIO *bio);
  90
  91 static int BIO_dgram_should_retry(int s);
  92
  93 static void get_current_time(struct timeval *t);
  94
  95 static BIO_METHOD methods_dgramp=
  96         {
  97         BIO_TYPE_DGRAM,
  98         "datagram socket",
  99         dgram_write,
 100         dgram_read,
 101         dgram_puts,
 102         NULL, /* dgram_gets, */
 103         dgram_ctrl,
 104         dgram_new,
 105         dgram_free,
 106         NULL,
 107         };
 108
 109 typedef struct bio_dgram_data_st
 110         {
 111         struct sockaddr peer;
 112         unsigned int connected;
 113         unsigned int _errno;
 114         unsigned int mtu;
 115         struct timeval next_timeout;
 116         struct timeval socket_timeout;
 117         } bio_dgram_data;
 118
 119 BIO_METHOD *BIO_s_datagram(void)
 120         {
 121         return(&methods_dgramp);
 122         }
 123
 124 BIO *BIO_new_dgram(int fd, int close_flag)
 125         {
 126         BIO *ret;
 127
 128         ret=BIO_new(BIO_s_datagram());
 129         if (ret == NULL) return(NULL);
 130         BIO_set_fd(ret,fd,close_flag);
 131         return(ret);
 132         }
 133
 134 static int dgram_new(BIO *bi)
 135         {
 136         bio_dgram_data *data = NULL;
 137
 138         bi->init=0;
 139         bi->num=0;
 140         data = OPENSSL_malloc(sizeof(bio_dgram_data));
 141         if (data == NULL)
 142                 return 0;
 143         memset(data, 0x00, sizeof(bio_dgram_data));
 144     bi->ptr = data;
 145
 146         bi->flags=0;
 147         return(1);
 148         }
 149
 150 static int dgram_free(BIO *a)
 151         {
 152         bio_dgram_data *data;
 153
 154         if (a == NULL) return(0);
 155         if ( ! dgram_clear(a))
 156                 return 0;
 157
 158         data = (bio_dgram_data *)a->ptr;
 159         if(data != NULL) OPENSSL_free(data);
 160
 161         return(1);
 162         }
 163
 164 static int dgram_clear(BIO *a)
 165         {
 166         if (a == NULL) return(0);
 167         if (a->shutdown)
 168                 {
 169                 if (a->init)
 170                         {
 171                         SHUTDOWN2(a->num);
 172                         }
 173                 a->init=0;
 174                 a->flags=0;
 175                 }
 176         return(1);
 177         }
 178
 179 static void dgram_adjust_rcv_timeout(BIO *b)
 180         {
 181 #if defined(SO_RCVTIMEO)
 182         bio_dgram_data *data = (bio_dgram_data *)b->ptr;
 183         int sz = sizeof(int);
 184
 185         /* Is a timer active? */
 186         if (data->next_timeout.tv_sec > 0 || data->next_timeout.tv_usec > 0)
 187                 {
 188                 struct timeval timenow, timeleft;
 189
 190                 /* Read current socket timeout */
 191 #ifdef OPENSSL_SYS_WINDOWS
 192                 int timeout;
 193                 if (getsockopt(b->num, SOL_SOCKET, SO_RCVTIMEO,
 194                                            (void*)&timeout, &sz) < 0)
 195                         { perror("getsockopt"); }
 196                 else
 197                         {
 198                         data->socket_timeout.tv_sec = timeout / 1000;
 199                         data->socket_timeout.tv_usec = (timeout % 1000) * 1000;
 200                         }
 201 #else
 202                 if ( getsockopt(b->num, SOL_SOCKET, SO_RCVTIMEO,
 203                                                 &(data->socket_timeout), (void *)&sz) < 0)
 204                         { perror("getsockopt"); }
 205 #endif
 206
 207                 /* Get current time */
 208                 get_current_time(&timenow);
 209
 210                 /* Calculate time left until timer expires */
 211                 memcpy(&timeleft, &(data->next_timeout), sizeof(struct timeval));
 212                 timeleft.tv_sec -= timenow.tv_sec;
 213                 timeleft.tv_usec -= timenow.tv_usec;
 214                 if (timeleft.tv_usec < 0)
 215                         {
 216                         timeleft.tv_sec--;
 217                         timeleft.tv_usec += 1000000;
 218                         }
 219
 220                 if (timeleft.tv_sec < 0)
 221                         {
 222                         timeleft.tv_sec = 0;
 223                         timeleft.tv_usec = 1;
 224                         }
 225
 226                 /* Adjust socket timeout if next handhake message timer
 227                  * will expire earlier.
 228                  */
 229                 if ((data->socket_timeout.tv_sec == 0 && data->socket_timeout.tv_usec == 0) ||
 230                         (data->socket_timeout.tv_sec > timeleft.tv_sec) ||
 231                         (data->socket_timeout.tv_sec == timeleft.tv_sec &&
 232                          data->socket_timeout.tv_usec >= timeleft.tv_usec))
 233                         {
 234 #ifdef OPENSSL_SYS_WINDOWS
 235                         timeout = timeleft.tv_sec * 1000 + timeleft.tv_usec / 1000;
 236                         if (setsockopt(b->num, SOL_SOCKET, SO_RCVTIMEO,
 237                                                    (void*)&timeout, sizeof(timeout)) < 0)
 238                                 { perror("setsockopt"); }
 239 #else
 240                         if ( setsockopt(b->num, SOL_SOCKET, SO_RCVTIMEO, &timeleft,
 241                                                         sizeof(struct timeval)) < 0)
 242                                 { perror("setsockopt"); }
 243 #endif
 244                         }
 245                 }
 246 #endif
 247         }
 248
 249 static void dgram_reset_rcv_timeout(BIO *b)
 250         {
 251 #if defined(SO_RCVTIMEO)
 252         bio_dgram_data *data = (bio_dgram_data *)b->ptr;
 253 #ifdef OPENSSL_SYS_WINDOWS
 254         int timeout = data->socket_timeout.tv_sec * 1000 +
 255                                   data->socket_timeout.tv_usec / 1000;
 256         if (setsockopt(b->num, SOL_SOCKET, SO_RCVTIMEO,
 257                                    (void*)&timeout, sizeof(timeout)) < 0)
 258                 { perror("setsockopt"); }
 259 #else
 260         if ( setsockopt(b->num, SOL_SOCKET, SO_RCVTIMEO, &(data->socket_timeout),
 261                                         sizeof(struct timeval)) < 0)
 262                 { perror("setsockopt"); }
 263 #endif
 264 #endif
 265         }
 266
 267 static int dgram_read(BIO *b, char *out, int outl)
 268         {
 269         int ret=0;
 270         bio_dgram_data *data = (bio_dgram_data *)b->ptr;
 271
 272         struct sockaddr peer;
 273         int peerlen = sizeof(peer);
 274
 275         if (out != NULL)
 276                 {
 277                 clear_socket_error();
 278                 memset(&peer, 0x00, peerlen);
 279                 /* Last arg in recvfrom is signed on some platforms and
 280                  * unsigned on others. It is of type socklen_t on some
 281                  * but this is not universal. Cast to (void *) to avoid
 282                  * compiler warnings.
 283                  */
 284                 dgram_adjust_rcv_timeout(b);
 285                 ret=recvfrom(b->num,out,outl,0,&peer,(void *)&peerlen);
 286                 dgram_reset_rcv_timeout(b);
 287
 288                 if ( ! data->connected  && ret > 0)
 289                         BIO_ctrl(b, BIO_CTRL_DGRAM_CONNECT, 0, &peer);
 290
 291                 BIO_clear_retry_flags(b);
 292                 if (ret <= 0)
 293                         {
 294                         if (BIO_dgram_should_retry(ret))
 295                                 {
 296                                 BIO_set_retry_read(b);
 297                                 data->_errno = get_last_socket_error();
 298                                 }
 299                         }
 300                 }
 301         return(ret);
 302         }
 303
 304 static int dgram_write(BIO *b, const char *in, int inl)
 305         {
 306         int ret;
 307         bio_dgram_data *data = (bio_dgram_data *)b->ptr;
 308         clear_socket_error();
 309
 310     if ( data->connected )
 311         ret=writesocket(b->num,in,inl);
 312     else
 313 #if defined(NETWARE_CLIB) && defined(NETWARE_BSDSOCK)
 314         ret=sendto(b->num, (char *)in, inl, 0, &data->peer, sizeof(data->peer));
 315 #else
 316         ret=sendto(b->num, in, inl, 0, &data->peer, sizeof(data->peer));
 317 #endif
 318
 319         BIO_clear_retry_flags(b);
 320         if (ret <= 0)
 321                 {
 322                 if (BIO_sock_should_retry(ret))
 323                         {
 324                         BIO_set_retry_write(b);
 325                         data->_errno = get_last_socket_error();
 326
 327 #if 0 /* higher layers are responsible for querying MTU, if necessary */
 328                         if ( data->_errno == EMSGSIZE)
 329                                 /* retrieve the new MTU */
 330                                 BIO_ctrl(b, BIO_CTRL_DGRAM_QUERY_MTU, 0, NULL);
 331 #endif
 332                         }
 333                 }
 334         return(ret);
 335         }
 336
 337 static long dgram_ctrl(BIO *b, int cmd, long num, void *ptr)
 338         {
 339         long ret=1;
 340         int *ip;
 341         struct sockaddr *to = NULL;
 342         bio_dgram_data *data = NULL;
 343 #if defined(IP_MTU_DISCOVER) || defined(IP_MTU)
 344         long sockopt_val = 0;
 345         unsigned int sockopt_len = 0;
 346 #endif
 347 #ifdef OPENSSL_SYS_LINUX
 348         socklen_t addr_len;
 349         struct sockaddr_storage addr;
 350 #endif
 351
 352         data = (bio_dgram_data *)b->ptr;
 353
 354         switch (cmd)
 355                 {
 356         case BIO_CTRL_RESET:
 357                 num=0;
 358         case BIO_C_FILE_SEEK:
 359                 ret=0;
 360                 break;
 361         case BIO_C_FILE_TELL:
 362         case BIO_CTRL_INFO:
 363                 ret=0;
 364                 break;
 365         case BIO_C_SET_FD:
 366                 dgram_clear(b);
 367                 b->num= *((int *)ptr);
 368                 b->shutdown=(int)num;
 369                 b->init=1;
 370                 break;
 371         case BIO_C_GET_FD:
 372                 if (b->init)
 373                         {
 374                         ip=(int *)ptr;
 375                         if (ip != NULL) *ip=b->num;
 376                         ret=b->num;
 377                         }
 378                 else
 379                         ret= -1;
 380                 break;
 381         case BIO_CTRL_GET_CLOSE:
 382                 ret=b->shutdown;
 383                 break;
 384         case BIO_CTRL_SET_CLOSE:
 385                 b->shutdown=(int)num;
 386                 break;
 387         case BIO_CTRL_PENDING:
 388         case BIO_CTRL_WPENDING:
 389                 ret=0;
 390                 break;
 391         case BIO_CTRL_DUP:
 392         case BIO_CTRL_FLUSH:
 393                 ret=1;
 394                 break;
 395         case BIO_CTRL_DGRAM_CONNECT:
 396                 to = (struct sockaddr *)ptr;
 397 #if 0
 398                 if (connect(b->num, to, sizeof(struct sockaddr)) < 0)
 399                         { perror("connect"); ret = 0; }
 400                 else
 401                         {
 402 #endif
 403                         memcpy(&(data->peer),to, sizeof(struct sockaddr));
 404 #if 0
 405                         }
 406 #endif
 407                 break;
 408                 /* (Linux)kernel sets DF bit on outgoing IP packets */
 409         case BIO_CTRL_DGRAM_MTU_DISCOVER:
 410 #ifdef OPENSSL_SYS_LINUX
 411                 addr_len = (socklen_t)sizeof(struct sockaddr_storage);
 412                 memset((void *)&addr, 0, sizeof(struct sockaddr_storage));
 413                 if (getsockname(b->num, (void *)&addr, &addr_len) < 0)
 414                         {
 415                         ret = 0;
 416                         break;
 417                         }
 418                 sockopt_len = sizeof(sockopt_val);
 419                 switch (addr.ss_family)
 420                         {
 421                 case AF_INET:
 422                         sockopt_val = IP_PMTUDISC_DO;
 423                         if ((ret = setsockopt(b->num, IPPROTO_IP, IP_MTU_DISCOVER,
 424                                 &sockopt_val, sizeof(sockopt_val))) < 0)
 425                                 perror("setsockopt");
 426                         break;
 427                 case AF_INET6:
 428                         sockopt_val = IPV6_PMTUDISC_DO;
 429                         if ((ret = setsockopt(b->num, IPPROTO_IPV6, IPV6_MTU_DISCOVER,
 430                                 &sockopt_val, sizeof(sockopt_val))) < 0)
 431                                 perror("setsockopt");
 432                         break;
 433                 default:
 434                         ret = -1;
 435                         break;
 436                         }
 437                 ret = -1;
 438 #else
 439                 break;
 440 #endif
 441         case BIO_CTRL_DGRAM_QUERY_MTU:
 442 #ifdef OPENSSL_SYS_LINUX
 443                 addr_len = (socklen_t)sizeof(struct sockaddr_storage);
 444                 memset((void *)&addr, 0, sizeof(struct sockaddr_storage));
 445                 if (getsockname(b->num, (void *)&addr, &addr_len) < 0)
 446                         {
 447                         ret = 0;
 448                         break;
 449                         }
 450                 sockopt_len = sizeof(sockopt_val);
 451                 switch (addr.ss_family)
 452                         {
 453                 case AF_INET:
 454                         if ((ret = getsockopt(b->num, IPPROTO_IP, IP_MTU, (void *)&sockopt_val,
 455                                 &sockopt_len)) < 0 || sockopt_val < 0)
 456                                 {
 457                                 ret = 0;
 458                                 }
 459                         else
 460                                 {
 461                                 /* we assume that the transport protocol is UDP and no
 462                                  * IP options are used.
 463                                  */
 464                                 data->mtu = sockopt_val - 8 - 20;
 465                                 ret = data->mtu;
 466                                 }
 467                         break;
 468                 case AF_INET6:
 469                         if ((ret = getsockopt(b->num, IPPROTO_IPV6, IPV6_MTU, (void *)&sockopt_val,
 470                                 &sockopt_len)) < 0 || sockopt_val < 0)
 471                                 {
 472                                 ret = 0;
 473                                 }
 474                         else
 475                                 {
 476                                 /* we assume that the transport protocol is UDP and no
 477                                  * IPV6 options are used.
 478                                  */
 479                                 data->mtu = sockopt_val - 8 - 40;
 480                                 ret = data->mtu;
 481                                 }
 482                         break;
 483                 default:
 484                         ret = 0;
 485                         break;
 486                         }
 487 #else
 488                 ret = 0;
 489 #endif
 490                 break;
 491         case BIO_CTRL_DGRAM_GET_MTU:
 492                 return data->mtu;
 493                 break;
 494         case BIO_CTRL_DGRAM_SET_MTU:
 495                 data->mtu = num;
 496                 ret = num;
 497                 break;
 498         case BIO_CTRL_DGRAM_SET_CONNECTED:
 499                 to = (struct sockaddr *)ptr;
 500
 501                 if ( to != NULL)
 502                         {
 503                         data->connected = 1;
 504                         memcpy(&(data->peer),to, sizeof(struct sockaddr));
 505                         }
 506                 else
 507                         {
 508                         data->connected = 0;
 509                         memset(&(data->peer), 0x00, sizeof(struct sockaddr));
 510                         }
 511                 break;
 512     case BIO_CTRL_DGRAM_SET_PEER:
 513         to = (struct sockaddr *) ptr;
 514
 515         memcpy(&(data->peer), to, sizeof(struct sockaddr));
 516         break;
 517         case BIO_CTRL_DGRAM_SET_NEXT_TIMEOUT:
 518                 memcpy(&(data->next_timeout), ptr, sizeof(struct timeval));
 519                 break;
 520 #if defined(SO_RCVTIMEO)
 521         case BIO_CTRL_DGRAM_SET_RECV_TIMEOUT:
 522 #ifdef OPENSSL_SYS_WINDOWS
 523                 {
 524                 struct timeval *tv = (struct timeval *)ptr;
 525                 int timeout = tv->tv_sec * 1000 + tv->tv_usec/1000;
 526                 if (setsockopt(b->num, SOL_SOCKET, SO_RCVTIMEO,
 527                         (void*)&timeout, sizeof(timeout)) < 0)
 528                         { perror("setsockopt"); ret = -1; }
 529                 }
 530 #else
 531                 if ( setsockopt(b->num, SOL_SOCKET, SO_RCVTIMEO, ptr,
 532                         sizeof(struct timeval)) < 0)
 533                         { perror("setsockopt"); ret = -1; }
 534 #endif
 535                 break;
 536         case BIO_CTRL_DGRAM_GET_RECV_TIMEOUT:
 537 #ifdef OPENSSL_SYS_WINDOWS
 538                 {
 539                 int timeout, sz = sizeof(timeout);
 540                 struct timeval *tv = (struct timeval *)ptr;
 541                 if (getsockopt(b->num, SOL_SOCKET, SO_RCVTIMEO,
 542                         (void*)&timeout, &sz) < 0)
 543                         { perror("getsockopt"); ret = -1; }
 544                 else
 545                         {
 546                         tv->tv_sec = timeout / 1000;
 547                         tv->tv_usec = (timeout % 1000) * 1000;
 548                         ret = sizeof(*tv);
 549                         }
 550                 }
 551 #else
 552                 if ( getsockopt(b->num, SOL_SOCKET, SO_RCVTIMEO,
 553                         ptr, (void *)&ret) < 0)
 554                         { perror("getsockopt"); ret = -1; }
 555 #endif
 556                 break;
 557 #endif
 558 #if defined(SO_SNDTIMEO)
 559         case BIO_CTRL_DGRAM_SET_SEND_TIMEOUT:
 560 #ifdef OPENSSL_SYS_WINDOWS
 561                 {
 562                 struct timeval *tv = (struct timeval *)ptr;
 563                 int timeout = tv->tv_sec * 1000 + tv->tv_usec/1000;
 564                 if (setsockopt(b->num, SOL_SOCKET, SO_SNDTIMEO,
 565                         (void*)&timeout, sizeof(timeout)) < 0)
 566                         { perror("setsockopt"); ret = -1; }
 567                 }
 568 #else
 569                 if ( setsockopt(b->num, SOL_SOCKET, SO_SNDTIMEO, ptr,
 570                         sizeof(struct timeval)) < 0)
 571                         { perror("setsockopt"); ret = -1; }
 572 #endif
 573                 break;
 574         case BIO_CTRL_DGRAM_GET_SEND_TIMEOUT:
 575 #ifdef OPENSSL_SYS_WINDOWS
 576                 {
 577                 int timeout, sz = sizeof(timeout);
 578                 struct timeval *tv = (struct timeval *)ptr;
 579                 if (getsockopt(b->num, SOL_SOCKET, SO_SNDTIMEO,
 580                         (void*)&timeout, &sz) < 0)
 581                         { perror("getsockopt"); ret = -1; }
 582                 else
 583                         {
 584                         tv->tv_sec = timeout / 1000;
 585                         tv->tv_usec = (timeout % 1000) * 1000;
 586                         ret = sizeof(*tv);
 587                         }
 588                 }
 589 #else
 590                 if ( getsockopt(b->num, SOL_SOCKET, SO_SNDTIMEO,
 591                         ptr, (void *)&ret) < 0)
 592                         { perror("getsockopt"); ret = -1; }
 593 #endif
 594                 break;
 595 #endif
 596         case BIO_CTRL_DGRAM_GET_SEND_TIMER_EXP:
 597                 /* fall-through */
 598         case BIO_CTRL_DGRAM_GET_RECV_TIMER_EXP:
 599 #ifdef OPENSSL_SYS_WINDOWS
 600                 if ( data->_errno == WSAETIMEDOUT)
 601 #else
 602                 if ( data->_errno == EAGAIN)
 603 #endif
 604                         {
 605                         ret = 1;
 606                         data->_errno = 0;
 607                         }
 608                 else
 609                         ret = 0;
 610                 break;
 611 #ifdef EMSGSIZE
 612         case BIO_CTRL_DGRAM_MTU_EXCEEDED:
 613                 if ( data->_errno == EMSGSIZE)
 614                         {
 615                         ret = 1;
 616                         data->_errno = 0;
 617                         }
 618                 else
 619                         ret = 0;
 620                 break;
 621 #endif
 622         default:
 623                 ret=0;
 624                 break;
 625                 }
 626         return(ret);
 627         }
 628
 629 static int dgram_puts(BIO *bp, const char *str)
 630         {
 631         int n,ret;
 632
 633         n=strlen(str);
 634         ret=dgram_write(bp,str,n);
 635         return(ret);
 636         }
 637
 638 static int BIO_dgram_should_retry(int i)
 639         {
 640         int err;
 641
 642         if ((i == 0) || (i == -1))
 643                 {
 644                 err=get_last_socket_error();
 645
 646 #if defined(OPENSSL_SYS_WINDOWS) && 0 /* more microsoft stupidity? perhaps not? Ben 4/1/99 */
 647                 if ((i == -1) && (err == 0))
 648                         return(1);
 649 #endif
 650
 651                 return(BIO_dgram_non_fatal_error(err));
 652                 }
 653         return(0);
 654         }
 655
 656 int BIO_dgram_non_fatal_error(int err)
 657         {
 658         switch (err)
 659                 {
 660 #if defined(OPENSSL_SYS_WINDOWS)
 661 # if defined(WSAEWOULDBLOCK)
 662         case WSAEWOULDBLOCK:
 663 # endif
 664
 665 # if 0 /* This appears to always be an error */
 666 #  if defined(WSAENOTCONN)
 667         case WSAENOTCONN:
 668 #  endif
 669 # endif
 670 #endif
 671
 672 #ifdef EWOULDBLOCK
 673 # ifdef WSAEWOULDBLOCK
 674 #  if WSAEWOULDBLOCK != EWOULDBLOCK
 675         case EWOULDBLOCK:
 676 #  endif
 677 # else
 678         case EWOULDBLOCK:
 679 # endif
 680 #endif
 681
 682 #if defined(ENOTCONN)
 683         case ENOTCONN:
 684 #endif
 685
 686 #ifdef EINTR
 687         case EINTR:
 688 #endif
 689
 690 #ifdef EAGAIN
 691 #if EWOULDBLOCK != EAGAIN
 692         case EAGAIN:
 693 # endif
 694 #endif
 695
 696 #ifdef EPROTO
 697         case EPROTO:
 698 #endif
 699
 700 #ifdef EINPROGRESS
 701         case EINPROGRESS:
 702 #endif
 703
 704 #ifdef EALREADY
 705         case EALREADY:
 706 #endif
 707
 708 /* DF bit set, and packet larger than MTU */
 709 #ifdef EMSGSIZE
 710         case EMSGSIZE:
 711 #endif
 712
 713                 return(1);
 714                 /* break; */
 715         default:
 716                 break;
 717                 }
 718         return(0);
 719         }
 720 #endif
 721
 722 static void get_current_time(struct timeval *t)
 723         {
 724 #ifdef OPENSSL_SYS_WIN32
 725         struct _timeb tb;
 726         _ftime(&tb);
 727         t->tv_sec = (long)tb.time;
 728         t->tv_usec = (long)tb.millitm * 1000;
 729 #elif defined(OPENSSL_SYS_VMS)
 730         struct timeb tb;
 731         ftime(&tb);
 732         t->tv_sec = (long)tb.time;
 733         t->tv_usec = (long)tb.millitm * 1000;
 734 #else
 735         gettimeofday(t, NULL);
 736 #endif
 737         }