crypto/openssl/ssl/d1_lib.c

   1 /* ssl/d1_lib.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 #include <stdio.h>
  61 #define USE_SOCKETS
  62 #include <openssl/objects.h>
  63 #include "ssl_locl.h"
  64
  65 #if defined(OPENSSL_SYS_WIN32) || defined(OPENSSL_SYS_VMS)
  66 #include <sys/timeb.h>
  67 #endif
  68
  69 static void get_current_time(struct timeval *t);
  70 const char dtls1_version_str[]="DTLSv1" OPENSSL_VERSION_PTEXT;
  71 int dtls1_listen(SSL *s, struct sockaddr *client);
  72
  73 SSL3_ENC_METHOD DTLSv1_enc_data={
  74     dtls1_enc,
  75         tls1_mac,
  76         tls1_setup_key_block,
  77         tls1_generate_master_secret,
  78         tls1_change_cipher_state,
  79         tls1_final_finish_mac,
  80         TLS1_FINISH_MAC_LENGTH,
  81         tls1_cert_verify_mac,
  82         TLS_MD_CLIENT_FINISH_CONST,TLS_MD_CLIENT_FINISH_CONST_SIZE,
  83         TLS_MD_SERVER_FINISH_CONST,TLS_MD_SERVER_FINISH_CONST_SIZE,
  84         tls1_alert_code,
  85         };
  86
  87 long dtls1_default_timeout(void)
  88         {
  89         /* 2 hours, the 24 hours mentioned in the DTLSv1 spec
  90          * is way too long for http, the cache would over fill */
  91         return(60*60*2);
  92         }
  93
  94 IMPLEMENT_dtls1_meth_func(dtlsv1_base_method,
  95                         ssl_undefined_function,
  96                         ssl_undefined_function,
  97                         ssl_bad_method)
  98
  99 int dtls1_new(SSL *s)
 100         {
 101         DTLS1_STATE *d1;
 102
 103         if (!ssl3_new(s)) return(0);
 104         if ((d1=OPENSSL_malloc(sizeof *d1)) == NULL) return (0);
 105         memset(d1,0, sizeof *d1);
 106
 107         /* d1->handshake_epoch=0; */
 108 #if defined(OPENSSL_SYS_VMS) || defined(VMS_TEST)
 109         d1->bitmap.length=64;
 110 #else
 111         d1->bitmap.length=sizeof(d1->bitmap.map) * 8;
 112 #endif
 113         pq_64bit_init(&(d1->bitmap.map));
 114         pq_64bit_init(&(d1->bitmap.max_seq_num));
 115
 116         d1->next_bitmap.length = d1->bitmap.length;
 117         pq_64bit_init(&(d1->next_bitmap.map));
 118         pq_64bit_init(&(d1->next_bitmap.max_seq_num));
 119
 120         d1->unprocessed_rcds.q=pqueue_new();
 121         d1->processed_rcds.q=pqueue_new();
 122         d1->buffered_messages = pqueue_new();
 123         d1->sent_messages=pqueue_new();
 124         d1->buffered_app_data.q=pqueue_new();
 125
 126         if ( s->server)
 127                 {
 128                 d1->cookie_len = sizeof(s->d1->cookie);
 129                 }
 130
 131         if( ! d1->unprocessed_rcds.q || ! d1->processed_rcds.q
 132         || ! d1->buffered_messages || ! d1->sent_messages || ! d1->buffered_app_data.q)
 133                 {
 134         if ( d1->unprocessed_rcds.q) pqueue_free(d1->unprocessed_rcds.q);
 135         if ( d1->processed_rcds.q) pqueue_free(d1->processed_rcds.q);
 136         if ( d1->buffered_messages) pqueue_free(d1->buffered_messages);
 137                 if ( d1->sent_messages) pqueue_free(d1->sent_messages);
 138                 if ( d1->buffered_app_data.q) pqueue_free(d1->buffered_app_data.q);
 139                 OPENSSL_free(d1);
 140                 return (0);
 141                 }
 142
 143         s->d1=d1;
 144         s->method->ssl_clear(s);
 145         return(1);
 146         }
 147
 148 void dtls1_free(SSL *s)
 149         {
 150     pitem *item = NULL;
 151     hm_fragment *frag = NULL;
 152
 153         ssl3_free(s);
 154
 155     while( (item = pqueue_pop(s->d1->unprocessed_rcds.q)) != NULL)
 156         {
 157         OPENSSL_free(item->data);
 158         pitem_free(item);
 159         }
 160     pqueue_free(s->d1->unprocessed_rcds.q);
 161
 162     while( (item = pqueue_pop(s->d1->processed_rcds.q)) != NULL)
 163         {
 164         OPENSSL_free(item->data);
 165         pitem_free(item);
 166         }
 167     pqueue_free(s->d1->processed_rcds.q);
 168
 169     while( (item = pqueue_pop(s->d1->buffered_messages)) != NULL)
 170         {
 171         frag = (hm_fragment *)item->data;
 172         OPENSSL_free(frag->fragment);
 173         OPENSSL_free(frag);
 174         pitem_free(item);
 175         }
 176     pqueue_free(s->d1->buffered_messages);
 177
 178     while ( (item = pqueue_pop(s->d1->sent_messages)) != NULL)
 179         {
 180         frag = (hm_fragment *)item->data;
 181         OPENSSL_free(frag->fragment);
 182         OPENSSL_free(frag);
 183         pitem_free(item);
 184         }
 185         pqueue_free(s->d1->sent_messages);
 186
 187         while ( (item = pqueue_pop(s->d1->buffered_app_data.q)) != NULL)
 188         {
 189                 frag = (hm_fragment *)item->data;
 190                 OPENSSL_free(frag->fragment);
 191                 OPENSSL_free(frag);
 192                 pitem_free(item);
 193         }
 194         pqueue_free(s->d1->buffered_app_data.q);
 195
 196         pq_64bit_free(&(s->d1->bitmap.map));
 197         pq_64bit_free(&(s->d1->bitmap.max_seq_num));
 198
 199         pq_64bit_free(&(s->d1->next_bitmap.map));
 200         pq_64bit_free(&(s->d1->next_bitmap.max_seq_num));
 201
 202         OPENSSL_free(s->d1);
 203         }
 204
 205 void dtls1_clear(SSL *s)
 206         {
 207         ssl3_clear(s);
 208         if (s->options & SSL_OP_CISCO_ANYCONNECT)
 209                 s->version=DTLS1_BAD_VER;
 210         else
 211                 s->version=DTLS1_VERSION;
 212         }
 213
 214 long dtls1_ctrl(SSL *s, int cmd, long larg, void *parg)
 215         {
 216         int ret=0;
 217
 218         switch (cmd)
 219                 {
 220         case DTLS_CTRL_GET_TIMEOUT:
 221                 if (dtls1_get_timeout(s, (struct timeval*) parg) != NULL)
 222                         {
 223                         ret = 1;
 224                         }
 225                 break;
 226         case DTLS_CTRL_HANDLE_TIMEOUT:
 227                 ret = dtls1_handle_timeout(s);
 228                 break;
 229         case DTLS_CTRL_LISTEN:
 230                 ret = dtls1_listen(s, parg);
 231                 break;
 232
 233         default:
 234                 ret = ssl3_ctrl(s, cmd, larg, parg);
 235                 break;
 236                 }
 237         return(ret);
 238         }
 239
 240 /*
 241  * As it's impossible to use stream ciphers in "datagram" mode, this
 242  * simple filter is designed to disengage them in DTLS. Unfortunately
 243  * there is no universal way to identify stream SSL_CIPHER, so we have
 244  * to explicitly list their SSL_* codes. Currently RC4 is the only one
 245  * available, but if new ones emerge, they will have to be added...
 246  */
 247 SSL_CIPHER *dtls1_get_cipher(unsigned int u)
 248         {
 249         SSL_CIPHER *ciph = ssl3_get_cipher(u);
 250
 251         if (ciph != NULL)
 252                 {
 253                 if ((ciph->algorithms&SSL_ENC_MASK) == SSL_RC4)
 254                         return NULL;
 255                 }
 256
 257         return ciph;
 258         }
 259
 260 void dtls1_start_timer(SSL *s)
 261         {
 262         /* If timer is not set, initialize duration with 1 second */
 263         if (s->d1->next_timeout.tv_sec == 0 && s->d1->next_timeout.tv_usec == 0)
 264                 {
 265                 s->d1->timeout_duration = 1;
 266                 }
 267
 268         /* Set timeout to current time */
 269         get_current_time(&(s->d1->next_timeout));
 270
 271         /* Add duration to current time */
 272         s->d1->next_timeout.tv_sec += s->d1->timeout_duration;
 273         BIO_ctrl(SSL_get_rbio(s), BIO_CTRL_DGRAM_SET_NEXT_TIMEOUT, 0, &(s->d1->next_timeout));
 274         }
 275
 276 struct timeval* dtls1_get_timeout(SSL *s, struct timeval* timeleft)
 277         {
 278         struct timeval timenow;
 279
 280         /* If no timeout is set, just return NULL */
 281         if (s->d1->next_timeout.tv_sec == 0 && s->d1->next_timeout.tv_usec == 0)
 282                 {
 283                 return NULL;
 284                 }
 285
 286         /* Get current time */
 287         get_current_time(&timenow);
 288
 289         /* If timer already expired, set remaining time to 0 */
 290         if (s->d1->next_timeout.tv_sec < timenow.tv_sec ||
 291                 (s->d1->next_timeout.tv_sec == timenow.tv_sec &&
 292                  s->d1->next_timeout.tv_usec <= timenow.tv_usec))
 293                 {
 294                 memset(timeleft, 0, sizeof(struct timeval));
 295                 return timeleft;
 296                 }
 297
 298         /* Calculate time left until timer expires */
 299         memcpy(timeleft, &(s->d1->next_timeout), sizeof(struct timeval));
 300         timeleft->tv_sec -= timenow.tv_sec;
 301         timeleft->tv_usec -= timenow.tv_usec;
 302         if (timeleft->tv_usec < 0)
 303                 {
 304                 timeleft->tv_sec--;
 305                 timeleft->tv_usec += 1000000;
 306                 }
 307
 308         return timeleft;
 309         }
 310
 311 int dtls1_is_timer_expired(SSL *s)
 312         {
 313         struct timeval timeleft;
 314
 315         /* Get time left until timeout, return false if no timer running */
 316         if (dtls1_get_timeout(s, &timeleft) == NULL)
 317                 {
 318                 return 0;
 319                 }
 320
 321         /* Return false if timer is not expired yet */
 322         if (timeleft.tv_sec > 0 || timeleft.tv_usec > 0)
 323                 {
 324                 return 0;
 325                 }
 326
 327         /* Timer expired, so return true */
 328         return 1;
 329         }
 330
 331 void dtls1_double_timeout(SSL *s)
 332         {
 333         s->d1->timeout_duration *= 2;
 334         if (s->d1->timeout_duration > 60)
 335                 s->d1->timeout_duration = 60;
 336         dtls1_start_timer(s);
 337         }
 338
 339 void dtls1_stop_timer(SSL *s)
 340         {
 341         /* Reset everything */
 342         memset(&(s->d1->next_timeout), 0, sizeof(struct timeval));
 343         s->d1->timeout_duration = 1;
 344         BIO_ctrl(SSL_get_rbio(s), BIO_CTRL_DGRAM_SET_NEXT_TIMEOUT, 0, &(s->d1->next_timeout));
 345         }
 346
 347 int dtls1_handle_timeout(SSL *s)
 348         {
 349         DTLS1_STATE *state;
 350
 351         /* if no timer is expired, don't do anything */
 352         if (!dtls1_is_timer_expired(s))
 353                 {
 354                 return 0;
 355                 }
 356
 357         dtls1_double_timeout(s);
 358         state = s->d1;
 359         state->timeout.num_alerts++;
 360         if ( state->timeout.num_alerts > DTLS1_TMO_ALERT_COUNT)
 361                 {
 362                 /* fail the connection, enough alerts have been sent */
 363                 SSLerr(SSL_F_DTLS1_HANDLE_TIMEOUT,SSL_R_READ_TIMEOUT_EXPIRED);
 364                 return 0;
 365                 }
 366
 367         state->timeout.read_timeouts++;
 368         if ( state->timeout.read_timeouts > DTLS1_TMO_READ_COUNT)
 369                 {
 370                 state->timeout.read_timeouts = 1;
 371                 }
 372
 373         dtls1_start_timer(s);
 374         return dtls1_retransmit_buffered_messages(s);
 375         }
 376
 377 static void get_current_time(struct timeval *t)
 378 {
 379 #ifdef OPENSSL_SYS_WIN32
 380         struct _timeb tb;
 381         _ftime(&tb);
 382         t->tv_sec = (long)tb.time;
 383         t->tv_usec = (long)tb.millitm * 1000;
 384 #elif defined(OPENSSL_SYS_VMS)
 385         struct timeb tb;
 386         ftime(&tb);
 387         t->tv_sec = (long)tb.time;
 388         t->tv_usec = (long)tb.millitm * 1000;
 389 #else
 390         gettimeofday(t, NULL);
 391 #endif
 392 }
 393
 394 int dtls1_listen(SSL *s, struct sockaddr *client)
 395         {
 396         int ret;
 397
 398         SSL_set_options(s, SSL_OP_COOKIE_EXCHANGE);
 399         s->d1->listen = 1;
 400
 401         ret = SSL_accept(s);
 402         if (ret <= 0) return ret;
 403
 404         (void) BIO_dgram_get_peer(SSL_get_rbio(s), client);
 405         return 1;
 406         }