crypto/openssl/ssl/d1_pkt.c

   1 /* ssl/d1_pkt.c */
   2 /*
   3  * DTLS implementation written by Nagendra Modadugu
   4  * (nagendra@cs.stanford.edu) for the OpenSSL project 2005.
   5  */
   6 /* ====================================================================
   7  * Copyright (c) 1998-2005 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 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
  60  * All rights reserved.
  61  *
  62  * This package is an SSL implementation written
  63  * by Eric Young (eay@cryptsoft.com).
  64  * The implementation was written so as to conform with Netscapes SSL.
  65  *
  66  * This library is free for commercial and non-commercial use as long as
  67  * the following conditions are aheared to.  The following conditions
  68  * apply to all code found in this distribution, be it the RC4, RSA,
  69  * lhash, DES, etc., code; not just the SSL code.  The SSL documentation
  70  * included with this distribution is covered by the same copyright terms
  71  * except that the holder is Tim Hudson (tjh@cryptsoft.com).
  72  *
  73  * Copyright remains Eric Young's, and as such any Copyright notices in
  74  * the code are not to be removed.
  75  * If this package is used in a product, Eric Young should be given attribution
  76  * as the author of the parts of the library used.
  77  * This can be in the form of a textual message at program startup or
  78  * in documentation (online or textual) provided with the package.
  79  *
  80  * Redistribution and use in source and binary forms, with or without
  81  * modification, are permitted provided that the following conditions
  82  * are met:
  83  * 1. Redistributions of source code must retain the copyright
  84  *    notice, this list of conditions and the following disclaimer.
  85  * 2. Redistributions in binary form must reproduce the above copyright
  86  *    notice, this list of conditions and the following disclaimer in the
  87  *    documentation and/or other materials provided with the distribution.
  88  * 3. All advertising materials mentioning features or use of this software
  89  *    must display the following acknowledgement:
  90  *    "This product includes cryptographic software written by
  91  *     Eric Young (eay@cryptsoft.com)"
  92  *    The word 'cryptographic' can be left out if the rouines from the library
  93  *    being used are not cryptographic related :-).
  94  * 4. If you include any Windows specific code (or a derivative thereof) from
  95  *    the apps directory (application code) you must include an acknowledgement:
  96  *    "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
  97  *
  98  * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
  99  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 100  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 101  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
 102  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 103  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 104  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 105  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 106  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 107  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 108  * SUCH DAMAGE.
 109  *
 110  * The licence and distribution terms for any publically available version or
 111  * derivative of this code cannot be changed.  i.e. this code cannot simply be
 112  * copied and put under another distribution licence
 113  * [including the GNU Public Licence.]
 114  */
 115
 116 #include <stdio.h>
 117 #include <errno.h>
 118 #define USE_SOCKETS
 119 #include "ssl_locl.h"
 120 #include <openssl/evp.h>
 121 #include <openssl/buffer.h>
 122 #include <openssl/pqueue.h>
 123 #include <openssl/rand.h>
 124
 125 /* mod 128 saturating subtract of two 64-bit values in big-endian order */
 126 static int satsub64be(const unsigned char *v1,const unsigned char *v2)
 127 {       int ret,sat,brw,i;
 128
 129         if (sizeof(long) == 8) do
 130         {       const union { long one; char little; } is_endian = {1};
 131                 long l;
 132
 133                 if (is_endian.little)                   break;
 134                 /* not reached on little-endians */
 135                 /* following test is redundant, because input is
 136                  * always aligned, but I take no chances... */
 137                 if (((size_t)v1|(size_t)v2)&0x7)        break;
 138
 139                 l  = *((long *)v1);
 140                 l -= *((long *)v2);
 141                 if (l>128)              return 128;
 142                 else if (l<-128)        return -128;
 143                 else                    return (int)l;
 144         } while (0);
 145
 146         ret = (int)v1[7]-(int)v2[7];
 147         sat = 0;
 148         brw = ret>>8;   /* brw is either 0 or -1 */
 149         if (ret & 0x80)
 150         {       for (i=6;i>=0;i--)
 151                 {       brw += (int)v1[i]-(int)v2[i];
 152                         sat |= ~brw;
 153                         brw >>= 8;
 154                 }
 155         }
 156         else
 157         {       for (i=6;i>=0;i--)
 158                 {       brw += (int)v1[i]-(int)v2[i];
 159                         sat |= brw;
 160                         brw >>= 8;
 161                 }
 162         }
 163         brw <<= 8;      /* brw is either 0 or -256 */
 164
 165         if (sat&0xff)   return brw | 0x80;
 166         else            return brw + (ret&0xFF);
 167 }
 168
 169 static int have_handshake_fragment(SSL *s, int type, unsigned char *buf,
 170         int len, int peek);
 171 static int dtls1_record_replay_check(SSL *s, DTLS1_BITMAP *bitmap);
 172 static void dtls1_record_bitmap_update(SSL *s, DTLS1_BITMAP *bitmap);
 173 static DTLS1_BITMAP *dtls1_get_bitmap(SSL *s, SSL3_RECORD *rr,
 174     unsigned int *is_next_epoch);
 175 #if 0
 176 static int dtls1_record_needs_buffering(SSL *s, SSL3_RECORD *rr,
 177         unsigned short *priority, unsigned long *offset);
 178 #endif
 179 static int dtls1_buffer_record(SSL *s, record_pqueue *q,
 180         unsigned char *priority);
 181 static int dtls1_process_record(SSL *s);
 182
 183 /* copy buffered record into SSL structure */
 184 static int
 185 dtls1_copy_record(SSL *s, pitem *item)
 186     {
 187     DTLS1_RECORD_DATA *rdata;
 188
 189     rdata = (DTLS1_RECORD_DATA *)item->data;
 190
 191     if (s->s3->rbuf.buf != NULL)
 192         OPENSSL_free(s->s3->rbuf.buf);
 193
 194     s->packet = rdata->packet;
 195     s->packet_length = rdata->packet_length;
 196     memcpy(&(s->s3->rbuf), &(rdata->rbuf), sizeof(SSL3_BUFFER));
 197     memcpy(&(s->s3->rrec), &(rdata->rrec), sizeof(SSL3_RECORD));
 198
 199         /* Set proper sequence number for mac calculation */
 200         memcpy(&(s->s3->read_sequence[2]), &(rdata->packet[5]), 6);
 201
 202     return(1);
 203     }
 204
 205
 206 static int
 207 dtls1_buffer_record(SSL *s, record_pqueue *queue, unsigned char *priority)
 208         {
 209         DTLS1_RECORD_DATA *rdata;
 210         pitem *item;
 211
 212         /* Limit the size of the queue to prevent DOS attacks */
 213         if (pqueue_size(queue->q) >= 100)
 214                 return 0;
 215
 216         rdata = OPENSSL_malloc(sizeof(DTLS1_RECORD_DATA));
 217         item = pitem_new(priority, rdata);
 218         if (rdata == NULL || item == NULL)
 219                 {
 220                 if (rdata != NULL) OPENSSL_free(rdata);
 221                 if (item != NULL) pitem_free(item);
 222
 223                 SSLerr(SSL_F_DTLS1_BUFFER_RECORD, ERR_R_INTERNAL_ERROR);
 224                 return(0);
 225                 }
 226
 227         rdata->packet = s->packet;
 228         rdata->packet_length = s->packet_length;
 229         memcpy(&(rdata->rbuf), &(s->s3->rbuf), sizeof(SSL3_BUFFER));
 230         memcpy(&(rdata->rrec), &(s->s3->rrec), sizeof(SSL3_RECORD));
 231
 232         item->data = rdata;
 233
 234 #ifndef OPENSSL_NO_SCTP
 235         /* Store bio_dgram_sctp_rcvinfo struct */
 236         if (BIO_dgram_is_sctp(SSL_get_rbio(s)) &&
 237             (s->state == SSL3_ST_SR_FINISHED_A || s->state == SSL3_ST_CR_FINISHED_A)) {
 238                 BIO_ctrl(SSL_get_rbio(s), BIO_CTRL_DGRAM_SCTP_GET_RCVINFO, sizeof(rdata->recordinfo), &rdata->recordinfo);
 239         }
 240 #endif
 241
 242         s->packet = NULL;
 243         s->packet_length = 0;
 244         memset(&(s->s3->rbuf), 0, sizeof(SSL3_BUFFER));
 245         memset(&(s->s3->rrec), 0, sizeof(SSL3_RECORD));
 246
 247         if (!ssl3_setup_buffers(s))
 248                 {
 249                 SSLerr(SSL_F_DTLS1_BUFFER_RECORD, ERR_R_INTERNAL_ERROR);
 250                 if (rdata->rbuf.buf != NULL)
 251                         OPENSSL_free(rdata->rbuf.buf);
 252                 OPENSSL_free(rdata);
 253                 pitem_free(item);
 254                 return(-1);
 255                 }
 256
 257         /* insert should not fail, since duplicates are dropped */
 258         if (pqueue_insert(queue->q, item) == NULL)
 259                 {
 260                 SSLerr(SSL_F_DTLS1_BUFFER_RECORD, ERR_R_INTERNAL_ERROR);
 261                 if (rdata->rbuf.buf != NULL)
 262                         OPENSSL_free(rdata->rbuf.buf);
 263                 OPENSSL_free(rdata);
 264                 pitem_free(item);
 265                 return(-1);
 266                 }
 267
 268         return(1);
 269         }
 270
 271
 272 static int
 273 dtls1_retrieve_buffered_record(SSL *s, record_pqueue *queue)
 274     {
 275     pitem *item;
 276
 277     item = pqueue_pop(queue->q);
 278     if (item)
 279         {
 280         dtls1_copy_record(s, item);
 281
 282         OPENSSL_free(item->data);
 283                 pitem_free(item);
 284
 285         return(1);
 286         }
 287
 288     return(0);
 289     }
 290
 291
 292 /* retrieve a buffered record that belongs to the new epoch, i.e., not processed
 293  * yet */
 294 #define dtls1_get_unprocessed_record(s) \
 295                    dtls1_retrieve_buffered_record((s), \
 296                    &((s)->d1->unprocessed_rcds))
 297
 298 /* retrieve a buffered record that belongs to the current epoch, ie, processed */
 299 #define dtls1_get_processed_record(s) \
 300                    dtls1_retrieve_buffered_record((s), \
 301                    &((s)->d1->processed_rcds))
 302
 303 static int
 304 dtls1_process_buffered_records(SSL *s)
 305     {
 306     pitem *item;
 307
 308     item = pqueue_peek(s->d1->unprocessed_rcds.q);
 309     if (item)
 310         {
 311         /* Check if epoch is current. */
 312         if (s->d1->unprocessed_rcds.epoch != s->d1->r_epoch)
 313             return(1);  /* Nothing to do. */
 314
 315         /* Process all the records. */
 316         while (pqueue_peek(s->d1->unprocessed_rcds.q))
 317             {
 318             dtls1_get_unprocessed_record(s);
 319             if ( ! dtls1_process_record(s))
 320                 return(0);
 321             if(dtls1_buffer_record(s, &(s->d1->processed_rcds),
 322                 s->s3->rrec.seq_num)<0)
 323                 return -1;
 324             }
 325         }
 326
 327     /* sync epoch numbers once all the unprocessed records
 328      * have been processed */
 329     s->d1->processed_rcds.epoch = s->d1->r_epoch;
 330     s->d1->unprocessed_rcds.epoch = s->d1->r_epoch + 1;
 331
 332     return(1);
 333     }
 334
 335
 336 #if 0
 337
 338 static int
 339 dtls1_get_buffered_record(SSL *s)
 340         {
 341         pitem *item;
 342         PQ_64BIT priority =
 343                 (((PQ_64BIT)s->d1->handshake_read_seq) << 32) |
 344                 ((PQ_64BIT)s->d1->r_msg_hdr.frag_off);
 345
 346         if ( ! SSL_in_init(s))  /* if we're not (re)negotiating,
 347                                                            nothing buffered */
 348                 return 0;
 349
 350
 351         item = pqueue_peek(s->d1->rcvd_records);
 352         if (item && item->priority == priority)
 353                 {
 354                 /* Check if we've received the record of interest.  It must be
 355                  * a handshake record, since data records as passed up without
 356                  * buffering */
 357                 DTLS1_RECORD_DATA *rdata;
 358                 item = pqueue_pop(s->d1->rcvd_records);
 359                 rdata = (DTLS1_RECORD_DATA *)item->data;
 360
 361                 if (s->s3->rbuf.buf != NULL)
 362                         OPENSSL_free(s->s3->rbuf.buf);
 363
 364                 s->packet = rdata->packet;
 365                 s->packet_length = rdata->packet_length;
 366                 memcpy(&(s->s3->rbuf), &(rdata->rbuf), sizeof(SSL3_BUFFER));
 367                 memcpy(&(s->s3->rrec), &(rdata->rrec), sizeof(SSL3_RECORD));
 368
 369                 OPENSSL_free(item->data);
 370                 pitem_free(item);
 371
 372                 /* s->d1->next_expected_seq_num++; */
 373                 return(1);
 374                 }
 375
 376         return 0;
 377         }
 378
 379 #endif
 380
 381 static int
 382 dtls1_process_record(SSL *s)
 383 {
 384         int i,al;
 385         int enc_err;
 386         SSL_SESSION *sess;
 387         SSL3_RECORD *rr;
 388         unsigned int mac_size, orig_len;
 389         unsigned char md[EVP_MAX_MD_SIZE];
 390
 391         rr= &(s->s3->rrec);
 392         sess = s->session;
 393
 394         /* At this point, s->packet_length == SSL3_RT_HEADER_LNGTH + rr->length,
 395          * and we have that many bytes in s->packet
 396          */
 397         rr->input= &(s->packet[DTLS1_RT_HEADER_LENGTH]);
 398
 399         /* ok, we can now read from 's->packet' data into 'rr'
 400          * rr->input points at rr->length bytes, which
 401          * need to be copied into rr->data by either
 402          * the decryption or by the decompression
 403          * When the data is 'copied' into the rr->data buffer,
 404          * rr->input will be pointed at the new buffer */
 405
 406         /* We now have - encrypted [ MAC [ compressed [ plain ] ] ]
 407          * rr->length bytes of encrypted compressed stuff. */
 408
 409         /* check is not needed I believe */
 410         if (rr->length > SSL3_RT_MAX_ENCRYPTED_LENGTH)
 411                 {
 412                 al=SSL_AD_RECORD_OVERFLOW;
 413                 SSLerr(SSL_F_DTLS1_PROCESS_RECORD,SSL_R_ENCRYPTED_LENGTH_TOO_LONG);
 414                 goto f_err;
 415                 }
 416
 417         /* decrypt in place in 'rr->input' */
 418         rr->data=rr->input;
 419
 420         enc_err = s->method->ssl3_enc->enc(s,0);
 421         /* enc_err is:
 422          *    0: (in non-constant time) if the record is publically invalid.
 423          *    1: if the padding is valid
 424          *    -1: if the padding is invalid */
 425         if (enc_err == 0)
 426                 {
 427                 /* For DTLS we simply ignore bad packets. */
 428                 rr->length = 0;
 429                 s->packet_length = 0;
 430                 goto err;
 431                 }
 432
 433 #ifdef TLS_DEBUG
 434 printf("dec %d\n",rr->length);
 435 { unsigned int z; for (z=0; z<rr->length; z++) printf("%02X%c",rr->data[z],((z+1)%16)?' ':'\n'); }
 436 printf("\n");
 437 #endif
 438
 439         /* r->length is now the compressed data plus mac */
 440         if ((sess != NULL) &&
 441             (s->enc_read_ctx != NULL) &&
 442             (EVP_MD_CTX_md(s->read_hash) != NULL))
 443                 {
 444                 /* s->read_hash != NULL => mac_size != -1 */
 445                 unsigned char *mac = NULL;
 446                 unsigned char mac_tmp[EVP_MAX_MD_SIZE];
 447                 mac_size=EVP_MD_CTX_size(s->read_hash);
 448                 OPENSSL_assert(mac_size <= EVP_MAX_MD_SIZE);
 449
 450                 /* kludge: *_cbc_remove_padding passes padding length in rr->type */
 451                 orig_len = rr->length+((unsigned int)rr->type>>8);
 452
 453                 /* orig_len is the length of the record before any padding was
 454                  * removed. This is public information, as is the MAC in use,
 455                  * therefore we can safely process the record in a different
 456                  * amount of time if it's too short to possibly contain a MAC.
 457                  */
 458                 if (orig_len < mac_size ||
 459                     /* CBC records must have a padding length byte too. */
 460                     (EVP_CIPHER_CTX_mode(s->enc_read_ctx) == EVP_CIPH_CBC_MODE &&
 461                      orig_len < mac_size+1))
 462                         {
 463                         al=SSL_AD_DECODE_ERROR;
 464                         SSLerr(SSL_F_DTLS1_PROCESS_RECORD,SSL_R_LENGTH_TOO_SHORT);
 465                         goto f_err;
 466                         }
 467
 468                 if (EVP_CIPHER_CTX_mode(s->enc_read_ctx) == EVP_CIPH_CBC_MODE)
 469                         {
 470                         /* We update the length so that the TLS header bytes
 471                          * can be constructed correctly but we need to extract
 472                          * the MAC in constant time from within the record,
 473                          * without leaking the contents of the padding bytes.
 474                          * */
 475                         mac = mac_tmp;
 476                         ssl3_cbc_copy_mac(mac_tmp, rr, mac_size, orig_len);
 477                         rr->length -= mac_size;
 478                         }
 479                 else
 480                         {
 481                         /* In this case there's no padding, so |orig_len|
 482                          * equals |rec->length| and we checked that there's
 483                          * enough bytes for |mac_size| above. */
 484                         rr->length -= mac_size;
 485                         mac = &rr->data[rr->length];
 486                         }
 487
 488                 i=s->method->ssl3_enc->mac(s,md,0 /* not send */);
 489                 if (i < 0 || mac == NULL || CRYPTO_memcmp(md, mac, (size_t)mac_size) != 0)
 490                         enc_err = -1;
 491                 if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH+mac_size)
 492                         enc_err = -1;
 493                 }
 494
 495         if (enc_err < 0)
 496                 {
 497                 /* decryption failed, silently discard message */
 498                 rr->length = 0;
 499                 s->packet_length = 0;
 500                 goto err;
 501                 }
 502
 503         /* r->length is now just compressed */
 504         if (s->expand != NULL)
 505                 {
 506                 if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH)
 507                         {
 508                         al=SSL_AD_RECORD_OVERFLOW;
 509                         SSLerr(SSL_F_DTLS1_PROCESS_RECORD,SSL_R_COMPRESSED_LENGTH_TOO_LONG);
 510                         goto f_err;
 511                         }
 512                 if (!ssl3_do_uncompress(s))
 513                         {
 514                         al=SSL_AD_DECOMPRESSION_FAILURE;
 515                         SSLerr(SSL_F_DTLS1_PROCESS_RECORD,SSL_R_BAD_DECOMPRESSION);
 516                         goto f_err;
 517                         }
 518                 }
 519
 520         if (rr->length > SSL3_RT_MAX_PLAIN_LENGTH)
 521                 {
 522                 al=SSL_AD_RECORD_OVERFLOW;
 523                 SSLerr(SSL_F_DTLS1_PROCESS_RECORD,SSL_R_DATA_LENGTH_TOO_LONG);
 524                 goto f_err;
 525                 }
 526
 527         rr->off=0;
 528         /* So at this point the following is true
 529          * ssl->s3->rrec.type   is the type of record
 530          * ssl->s3->rrec.length == number of bytes in record
 531          * ssl->s3->rrec.off    == offset to first valid byte
 532          * ssl->s3->rrec.data   == where to take bytes from, increment
 533          *                         after use :-).
 534          */
 535
 536         /* we have pulled in a full packet so zero things */
 537         s->packet_length=0;
 538         return(1);
 539
 540 f_err:
 541         ssl3_send_alert(s,SSL3_AL_FATAL,al);
 542 err:
 543         return(0);
 544 }
 545
 546
 547 /* Call this to get a new input record.
 548  * It will return <= 0 if more data is needed, normally due to an error
 549  * or non-blocking IO.
 550  * When it finishes, one packet has been decoded and can be found in
 551  * ssl->s3->rrec.type    - is the type of record
 552  * ssl->s3->rrec.data,   - data
 553  * ssl->s3->rrec.length, - number of bytes
 554  */
 555 /* used only by dtls1_read_bytes */
 556 int dtls1_get_record(SSL *s)
 557         {
 558         int ssl_major,ssl_minor;
 559         int i,n;
 560         SSL3_RECORD *rr;
 561         unsigned char *p = NULL;
 562         unsigned short version;
 563         DTLS1_BITMAP *bitmap;
 564         unsigned int is_next_epoch;
 565
 566         rr= &(s->s3->rrec);
 567
 568         /* The epoch may have changed.  If so, process all the
 569          * pending records.  This is a non-blocking operation. */
 570         if(dtls1_process_buffered_records(s)<0)
 571                 return -1;
 572
 573         /* if we're renegotiating, then there may be buffered records */
 574         if (dtls1_get_processed_record(s))
 575                 return 1;
 576
 577         /* get something from the wire */
 578 again:
 579         /* check if we have the header */
 580         if (    (s->rstate != SSL_ST_READ_BODY) ||
 581                 (s->packet_length < DTLS1_RT_HEADER_LENGTH))
 582                 {
 583                 n=ssl3_read_n(s, DTLS1_RT_HEADER_LENGTH, s->s3->rbuf.len, 0);
 584                 /* read timeout is handled by dtls1_read_bytes */
 585                 if (n <= 0) return(n); /* error or non-blocking */
 586
 587                 /* this packet contained a partial record, dump it */
 588                 if (s->packet_length != DTLS1_RT_HEADER_LENGTH)
 589                         {
 590                         s->packet_length = 0;
 591                         goto again;
 592                         }
 593
 594                 s->rstate=SSL_ST_READ_BODY;
 595
 596                 p=s->packet;
 597
 598                 /* Pull apart the header into the DTLS1_RECORD */
 599                 rr->type= *(p++);
 600                 ssl_major= *(p++);
 601                 ssl_minor= *(p++);
 602                 version=(ssl_major<<8)|ssl_minor;
 603
 604                 /* sequence number is 64 bits, with top 2 bytes = epoch */
 605                 n2s(p,rr->epoch);
 606
 607                 memcpy(&(s->s3->read_sequence[2]), p, 6);
 608                 p+=6;
 609
 610                 n2s(p,rr->length);
 611
 612                 /* Lets check version */
 613                 if (!s->first_packet)
 614                         {
 615                         if (version != s->version)
 616                                 {
 617                                 /* unexpected version, silently discard */
 618                                 rr->length = 0;
 619                                 s->packet_length = 0;
 620                                 goto again;
 621                                 }
 622                         }
 623
 624                 if ((version & 0xff00) != (s->version & 0xff00))
 625                         {
 626                         /* wrong version, silently discard record */
 627                         rr->length = 0;
 628                         s->packet_length = 0;
 629                         goto again;
 630                         }
 631
 632                 if (rr->length > SSL3_RT_MAX_ENCRYPTED_LENGTH)
 633                         {
 634                         /* record too long, silently discard it */
 635                         rr->length = 0;
 636                         s->packet_length = 0;
 637                         goto again;
 638                         }
 639
 640                 /* now s->rstate == SSL_ST_READ_BODY */
 641                 }
 642
 643         /* s->rstate == SSL_ST_READ_BODY, get and decode the data */
 644
 645         if (rr->length > s->packet_length-DTLS1_RT_HEADER_LENGTH)
 646                 {
 647                 /* now s->packet_length == DTLS1_RT_HEADER_LENGTH */
 648                 i=rr->length;
 649                 n=ssl3_read_n(s,i,i,1);
 650                 /* this packet contained a partial record, dump it */
 651                 if ( n != i)
 652                         {
 653                         rr->length = 0;
 654                         s->packet_length = 0;
 655                         goto again;
 656                         }
 657
 658                 /* now n == rr->length,
 659                  * and s->packet_length == DTLS1_RT_HEADER_LENGTH + rr->length */
 660                 }
 661         s->rstate=SSL_ST_READ_HEADER; /* set state for later operations */
 662
 663         /* match epochs.  NULL means the packet is dropped on the floor */
 664         bitmap = dtls1_get_bitmap(s, rr, &is_next_epoch);
 665         if ( bitmap == NULL)
 666                 {
 667                 rr->length = 0;
 668                 s->packet_length = 0;  /* dump this record */
 669                 goto again;   /* get another record */
 670                 }
 671
 672 #ifndef OPENSSL_NO_SCTP
 673         /* Only do replay check if no SCTP bio */
 674         if (!BIO_dgram_is_sctp(SSL_get_rbio(s)))
 675                 {
 676 #endif
 677                 /* Check whether this is a repeat, or aged record.
 678                  * Don't check if we're listening and this message is
 679                  * a ClientHello. They can look as if they're replayed,
 680                  * since they arrive from different connections and
 681                  * would be dropped unnecessarily.
 682                  */
 683                 if (!(s->d1->listen && rr->type == SSL3_RT_HANDSHAKE &&
 684                     s->packet_length > DTLS1_RT_HEADER_LENGTH &&
 685                     s->packet[DTLS1_RT_HEADER_LENGTH] == SSL3_MT_CLIENT_HELLO) &&
 686                     !dtls1_record_replay_check(s, bitmap))
 687                         {
 688                         rr->length = 0;
 689                         s->packet_length=0; /* dump this record */
 690                         goto again;     /* get another record */
 691                         }
 692 #ifndef OPENSSL_NO_SCTP
 693                 }
 694 #endif
 695
 696         /* just read a 0 length packet */
 697         if (rr->length == 0) goto again;
 698
 699         /* If this record is from the next epoch (either HM or ALERT),
 700          * and a handshake is currently in progress, buffer it since it
 701          * cannot be processed at this time. However, do not buffer
 702          * anything while listening.
 703          */
 704         if (is_next_epoch)
 705                 {
 706                 if ((SSL_in_init(s) || s->in_handshake) && !s->d1->listen)
 707                         {
 708                         if(dtls1_buffer_record(s, &(s->d1->unprocessed_rcds), rr->seq_num)<0)
 709                                 return -1;
 710                         dtls1_record_bitmap_update(s, bitmap);/* Mark receipt of record. */
 711                         }
 712                 rr->length = 0;
 713                 s->packet_length = 0;
 714                 goto again;
 715                 }
 716
 717         if (!dtls1_process_record(s))
 718                 {
 719                 rr->length = 0;
 720                 s->packet_length = 0;  /* dump this record */
 721                 goto again;   /* get another record */
 722                 }
 723         dtls1_record_bitmap_update(s, bitmap);/* Mark receipt of record. */
 724
 725         return(1);
 726
 727         }
 728
 729 /* Return up to 'len' payload bytes received in 'type' records.
 730  * 'type' is one of the following:
 731  *
 732  *   -  SSL3_RT_HANDSHAKE (when ssl3_get_message calls us)
 733  *   -  SSL3_RT_APPLICATION_DATA (when ssl3_read calls us)
 734  *   -  0 (during a shutdown, no data has to be returned)
 735  *
 736  * If we don't have stored data to work from, read a SSL/TLS record first
 737  * (possibly multiple records if we still don't have anything to return).
 738  *
 739  * This function must handle any surprises the peer may have for us, such as
 740  * Alert records (e.g. close_notify), ChangeCipherSpec records (not really
 741  * a surprise, but handled as if it were), or renegotiation requests.
 742  * Also if record payloads contain fragments too small to process, we store
 743  * them until there is enough for the respective protocol (the record protocol
 744  * may use arbitrary fragmentation and even interleaving):
 745  *     Change cipher spec protocol
 746  *             just 1 byte needed, no need for keeping anything stored
 747  *     Alert protocol
 748  *             2 bytes needed (AlertLevel, AlertDescription)
 749  *     Handshake protocol
 750  *             4 bytes needed (HandshakeType, uint24 length) -- we just have
 751  *             to detect unexpected Client Hello and Hello Request messages
 752  *             here, anything else is handled by higher layers
 753  *     Application data protocol
 754  *             none of our business
 755  */
 756 int dtls1_read_bytes(SSL *s, int type, unsigned char *buf, int len, int peek)
 757         {
 758         int al,i,j,ret;
 759         unsigned int n;
 760         SSL3_RECORD *rr;
 761         void (*cb)(const SSL *ssl,int type2,int val)=NULL;
 762
 763         if (s->s3->rbuf.buf == NULL) /* Not initialized yet */
 764                 if (!ssl3_setup_buffers(s))
 765                         return(-1);
 766
 767     /* XXX: check what the second '&& type' is about */
 768         if ((type && (type != SSL3_RT_APPLICATION_DATA) &&
 769                 (type != SSL3_RT_HANDSHAKE) && type) ||
 770             (peek && (type != SSL3_RT_APPLICATION_DATA)))
 771                 {
 772                 SSLerr(SSL_F_DTLS1_READ_BYTES, ERR_R_INTERNAL_ERROR);
 773                 return -1;
 774                 }
 775
 776         /* check whether there's a handshake message (client hello?) waiting */
 777         if ( (ret = have_handshake_fragment(s, type, buf, len, peek)))
 778                 return ret;
 779
 780         /* Now s->d1->handshake_fragment_len == 0 if type == SSL3_RT_HANDSHAKE. */
 781
 782 #ifndef OPENSSL_NO_SCTP
 783         /* Continue handshake if it had to be interrupted to read
 784          * app data with SCTP.
 785          */
 786         if ((!s->in_handshake && SSL_in_init(s)) ||
 787             (BIO_dgram_is_sctp(SSL_get_rbio(s)) &&
 788              (s->state == DTLS1_SCTP_ST_SR_READ_SOCK || s->state == DTLS1_SCTP_ST_CR_READ_SOCK) &&
 789              s->s3->in_read_app_data != 2))
 790 #else
 791         if (!s->in_handshake && SSL_in_init(s))
 792 #endif
 793                 {
 794                 /* type == SSL3_RT_APPLICATION_DATA */
 795                 i=s->handshake_func(s);
 796                 if (i < 0) return(i);
 797                 if (i == 0)
 798                         {
 799                         SSLerr(SSL_F_DTLS1_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
 800                         return(-1);
 801                         }
 802                 }
 803
 804 start:
 805         s->rwstate=SSL_NOTHING;
 806
 807         /* s->s3->rrec.type         - is the type of record
 808          * s->s3->rrec.data,    - data
 809          * s->s3->rrec.off,     - offset into 'data' for next read
 810          * s->s3->rrec.length,  - number of bytes. */
 811         rr = &(s->s3->rrec);
 812
 813         /* We are not handshaking and have no data yet,
 814          * so process data buffered during the last handshake
 815          * in advance, if any.
 816          */
 817         if (s->state == SSL_ST_OK && rr->length == 0)
 818                 {
 819                 pitem *item;
 820                 item = pqueue_pop(s->d1->buffered_app_data.q);
 821                 if (item)
 822                         {
 823 #ifndef OPENSSL_NO_SCTP
 824                         /* Restore bio_dgram_sctp_rcvinfo struct */
 825                         if (BIO_dgram_is_sctp(SSL_get_rbio(s)))
 826                                 {
 827                                 DTLS1_RECORD_DATA *rdata = (DTLS1_RECORD_DATA *) item->data;
 828                                 BIO_ctrl(SSL_get_rbio(s), BIO_CTRL_DGRAM_SCTP_SET_RCVINFO, sizeof(rdata->recordinfo), &rdata->recordinfo);
 829                                 }
 830 #endif
 831
 832                         dtls1_copy_record(s, item);
 833
 834                         OPENSSL_free(item->data);
 835                         pitem_free(item);
 836                         }
 837                 }
 838
 839         /* Check for timeout */
 840         if (dtls1_handle_timeout(s) > 0)
 841                 goto start;
 842
 843         /* get new packet if necessary */
 844         if ((rr->length == 0) || (s->rstate == SSL_ST_READ_BODY))
 845                 {
 846                 ret=dtls1_get_record(s);
 847                 if (ret <= 0)
 848                         {
 849                         ret = dtls1_read_failed(s, ret);
 850                         /* anything other than a timeout is an error */
 851                         if (ret <= 0)
 852                                 return(ret);
 853                         else
 854                                 goto start;
 855                         }
 856                 }
 857
 858         /* we now have a packet which can be read and processed */
 859
 860         if (s->s3->change_cipher_spec /* set when we receive ChangeCipherSpec,
 861                                        * reset by ssl3_get_finished */
 862                 && (rr->type != SSL3_RT_HANDSHAKE))
 863                 {
 864                 /* We now have application data between CCS and Finished.
 865                  * Most likely the packets were reordered on their way, so
 866                  * buffer the application data for later processing rather
 867                  * than dropping the connection.
 868                  */
 869                 if(dtls1_buffer_record(s, &(s->d1->buffered_app_data), rr->seq_num)<0)
 870                         {
 871                         SSLerr(SSL_F_DTLS1_READ_BYTES, ERR_R_INTERNAL_ERROR);
 872                         return -1;
 873                         }
 874                 rr->length = 0;
 875                 goto start;
 876                 }
 877
 878         /* If the other end has shut down, throw anything we read away
 879          * (even in 'peek' mode) */
 880         if (s->shutdown & SSL_RECEIVED_SHUTDOWN)
 881                 {
 882                 rr->length=0;
 883                 s->rwstate=SSL_NOTHING;
 884                 return(0);
 885                 }
 886
 887
 888         if (type == rr->type) /* SSL3_RT_APPLICATION_DATA or SSL3_RT_HANDSHAKE */
 889                 {
 890                 /* make sure that we are not getting application data when we
 891                  * are doing a handshake for the first time */
 892                 if (SSL_in_init(s) && (type == SSL3_RT_APPLICATION_DATA) &&
 893                         (s->enc_read_ctx == NULL))
 894                         {
 895                         al=SSL_AD_UNEXPECTED_MESSAGE;
 896                         SSLerr(SSL_F_DTLS1_READ_BYTES,SSL_R_APP_DATA_IN_HANDSHAKE);
 897                         goto f_err;
 898                         }
 899
 900                 if (len <= 0) return(len);
 901
 902                 if ((unsigned int)len > rr->length)
 903                         n = rr->length;
 904                 else
 905                         n = (unsigned int)len;
 906
 907                 memcpy(buf,&(rr->data[rr->off]),n);
 908                 if (!peek)
 909                         {
 910                         rr->length-=n;
 911                         rr->off+=n;
 912                         if (rr->length == 0)
 913                                 {
 914                                 s->rstate=SSL_ST_READ_HEADER;
 915                                 rr->off=0;
 916                                 }
 917                         }
 918
 919 #ifndef OPENSSL_NO_SCTP
 920                         /* We were about to renegotiate but had to read
 921                          * belated application data first, so retry.
 922                          */
 923                         if (BIO_dgram_is_sctp(SSL_get_rbio(s)) &&
 924                             rr->type == SSL3_RT_APPLICATION_DATA &&
 925                             (s->state == DTLS1_SCTP_ST_SR_READ_SOCK || s->state == DTLS1_SCTP_ST_CR_READ_SOCK))
 926                                 {
 927                                 s->rwstate=SSL_READING;
 928                                 BIO_clear_retry_flags(SSL_get_rbio(s));
 929                                 BIO_set_retry_read(SSL_get_rbio(s));
 930                                 }
 931
 932                         /* We might had to delay a close_notify alert because
 933                          * of reordered app data. If there was an alert and there
 934                          * is no message to read anymore, finally set shutdown.
 935                          */
 936                         if (BIO_dgram_is_sctp(SSL_get_rbio(s)) &&
 937                             s->d1->shutdown_received && !BIO_dgram_sctp_msg_waiting(SSL_get_rbio(s)))
 938                                 {
 939                                 s->shutdown |= SSL_RECEIVED_SHUTDOWN;
 940                                 return(0);
 941                                 }
 942 #endif
 943                 return(n);
 944                 }
 945
 946
 947         /* If we get here, then type != rr->type; if we have a handshake
 948          * message, then it was unexpected (Hello Request or Client Hello). */
 949
 950         /* In case of record types for which we have 'fragment' storage,
 951          * fill that so that we can process the data at a fixed place.
 952          */
 953                 {
 954                 unsigned int k, dest_maxlen = 0;
 955                 unsigned char *dest = NULL;
 956                 unsigned int *dest_len = NULL;
 957
 958                 if (rr->type == SSL3_RT_HANDSHAKE)
 959                         {
 960                         dest_maxlen = sizeof s->d1->handshake_fragment;
 961                         dest = s->d1->handshake_fragment;
 962                         dest_len = &s->d1->handshake_fragment_len;
 963                         }
 964                 else if (rr->type == SSL3_RT_ALERT)
 965                         {
 966                         dest_maxlen = sizeof(s->d1->alert_fragment);
 967                         dest = s->d1->alert_fragment;
 968                         dest_len = &s->d1->alert_fragment_len;
 969                         }
 970 #ifndef OPENSSL_NO_HEARTBEATS
 971                 else if (rr->type == TLS1_RT_HEARTBEAT)
 972                         {
 973                         dtls1_process_heartbeat(s);
 974
 975                         /* Exit and notify application to read again */
 976                         rr->length = 0;
 977                         s->rwstate=SSL_READING;
 978                         BIO_clear_retry_flags(SSL_get_rbio(s));
 979                         BIO_set_retry_read(SSL_get_rbio(s));
 980                         return(-1);
 981                         }
 982 #endif
 983                 /* else it's a CCS message, or application data or wrong */
 984                 else if (rr->type != SSL3_RT_CHANGE_CIPHER_SPEC)
 985                         {
 986                         /* Application data while renegotiating
 987                          * is allowed. Try again reading.
 988                          */
 989                         if (rr->type == SSL3_RT_APPLICATION_DATA)
 990                                 {
 991                                 BIO *bio;
 992                                 s->s3->in_read_app_data=2;
 993                                 bio=SSL_get_rbio(s);
 994                                 s->rwstate=SSL_READING;
 995                                 BIO_clear_retry_flags(bio);
 996                                 BIO_set_retry_read(bio);
 997                                 return(-1);
 998                                 }
 999
1000                         /* Not certain if this is the right error handling */
1001                         al=SSL_AD_UNEXPECTED_MESSAGE;
1002                         SSLerr(SSL_F_DTLS1_READ_BYTES,SSL_R_UNEXPECTED_RECORD);
1003                         goto f_err;
1004                         }
1005
1006                 if (dest_maxlen > 0)
1007                         {
1008             /* XDTLS:  In a pathalogical case, the Client Hello
1009              *  may be fragmented--don't always expect dest_maxlen bytes */
1010                         if ( rr->length < dest_maxlen)
1011                                 {
1012 #ifdef DTLS1_AD_MISSING_HANDSHAKE_MESSAGE
1013                                 /*
1014                                  * for normal alerts rr->length is 2, while
1015                                  * dest_maxlen is 7 if we were to handle this
1016                                  * non-existing alert...
1017                                  */
1018                                 FIX ME
1019 #endif
1020                                 s->rstate=SSL_ST_READ_HEADER;
1021                                 rr->length = 0;
1022                                 goto start;
1023                                 }
1024
1025                         /* now move 'n' bytes: */
1026                         for ( k = 0; k < dest_maxlen; k++)
1027                                 {
1028                                 dest[k] = rr->data[rr->off++];
1029                                 rr->length--;
1030                                 }
1031                         *dest_len = dest_maxlen;
1032                         }
1033                 }
1034
1035         /* s->d1->handshake_fragment_len == 12  iff  rr->type == SSL3_RT_HANDSHAKE;
1036          * s->d1->alert_fragment_len == 7      iff  rr->type == SSL3_RT_ALERT.
1037          * (Possibly rr is 'empty' now, i.e. rr->length may be 0.) */
1038
1039         /* If we are a client, check for an incoming 'Hello Request': */
1040         if ((!s->server) &&
1041                 (s->d1->handshake_fragment_len >= DTLS1_HM_HEADER_LENGTH) &&
1042                 (s->d1->handshake_fragment[0] == SSL3_MT_HELLO_REQUEST) &&
1043                 (s->session != NULL) && (s->session->cipher != NULL))
1044                 {
1045                 s->d1->handshake_fragment_len = 0;
1046
1047                 if ((s->d1->handshake_fragment[1] != 0) ||
1048                         (s->d1->handshake_fragment[2] != 0) ||
1049                         (s->d1->handshake_fragment[3] != 0))
1050                         {
1051                         al=SSL_AD_DECODE_ERROR;
1052                         SSLerr(SSL_F_DTLS1_READ_BYTES,SSL_R_BAD_HELLO_REQUEST);
1053                         goto err;
1054                         }
1055
1056                 /* no need to check sequence number on HELLO REQUEST messages */
1057
1058                 if (s->msg_callback)
1059                         s->msg_callback(0, s->version, SSL3_RT_HANDSHAKE,
1060                                 s->d1->handshake_fragment, 4, s, s->msg_callback_arg);
1061
1062                 if (SSL_is_init_finished(s) &&
1063                         !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS) &&
1064                         !s->s3->renegotiate)
1065                         {
1066                         s->new_session = 1;
1067                         ssl3_renegotiate(s);
1068                         if (ssl3_renegotiate_check(s))
1069                                 {
1070                                 i=s->handshake_func(s);
1071                                 if (i < 0) return(i);
1072                                 if (i == 0)
1073                                         {
1074                                         SSLerr(SSL_F_DTLS1_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
1075                                         return(-1);
1076                                         }
1077
1078                                 if (!(s->mode & SSL_MODE_AUTO_RETRY))
1079                                         {
1080                                         if (s->s3->rbuf.left == 0) /* no read-ahead left? */
1081                                                 {
1082                                                 BIO *bio;
1083                                                 /* In the case where we try to read application data,
1084                                                  * but we trigger an SSL handshake, we return -1 with
1085                                                  * the retry option set.  Otherwise renegotiation may
1086                                                  * cause nasty problems in the blocking world */
1087                                                 s->rwstate=SSL_READING;
1088                                                 bio=SSL_get_rbio(s);
1089                                                 BIO_clear_retry_flags(bio);
1090                                                 BIO_set_retry_read(bio);
1091                                                 return(-1);
1092                                                 }
1093                                         }
1094                                 }
1095                         }
1096                 /* we either finished a handshake or ignored the request,
1097                  * now try again to obtain the (application) data we were asked for */
1098                 goto start;
1099                 }
1100
1101         if (s->d1->alert_fragment_len >= DTLS1_AL_HEADER_LENGTH)
1102                 {
1103                 int alert_level = s->d1->alert_fragment[0];
1104                 int alert_descr = s->d1->alert_fragment[1];
1105
1106                 s->d1->alert_fragment_len = 0;
1107
1108                 if (s->msg_callback)
1109                         s->msg_callback(0, s->version, SSL3_RT_ALERT,
1110                                 s->d1->alert_fragment, 2, s, s->msg_callback_arg);
1111
1112                 if (s->info_callback != NULL)
1113                         cb=s->info_callback;
1114                 else if (s->ctx->info_callback != NULL)
1115                         cb=s->ctx->info_callback;
1116
1117                 if (cb != NULL)
1118                         {
1119                         j = (alert_level << 8) | alert_descr;
1120                         cb(s, SSL_CB_READ_ALERT, j);
1121                         }
1122
1123                 if (alert_level == 1) /* warning */
1124                         {
1125                         s->s3->warn_alert = alert_descr;
1126                         if (alert_descr == SSL_AD_CLOSE_NOTIFY)
1127                                 {
1128 #ifndef OPENSSL_NO_SCTP
1129                                 /* With SCTP and streams the socket may deliver app data
1130                                  * after a close_notify alert. We have to check this
1131                                  * first so that nothing gets discarded.
1132                                  */
1133                                 if (BIO_dgram_is_sctp(SSL_get_rbio(s)) &&
1134                                         BIO_dgram_sctp_msg_waiting(SSL_get_rbio(s)))
1135                                         {
1136                                         s->d1->shutdown_received = 1;
1137                                         s->rwstate=SSL_READING;
1138                                         BIO_clear_retry_flags(SSL_get_rbio(s));
1139                                         BIO_set_retry_read(SSL_get_rbio(s));
1140                                         return -1;
1141                                         }
1142 #endif
1143                                 s->shutdown |= SSL_RECEIVED_SHUTDOWN;
1144                                 return(0);
1145                                 }
1146 #if 0
1147             /* XXX: this is a possible improvement in the future */
1148                         /* now check if it's a missing record */
1149                         if (alert_descr == DTLS1_AD_MISSING_HANDSHAKE_MESSAGE)
1150                                 {
1151                                 unsigned short seq;
1152                                 unsigned int frag_off;
1153                                 unsigned char *p = &(s->d1->alert_fragment[2]);
1154
1155                                 n2s(p, seq);
1156                                 n2l3(p, frag_off);
1157
1158                                 dtls1_retransmit_message(s,
1159                                                                                  dtls1_get_queue_priority(frag->msg_header.seq, 0),
1160                                                                                  frag_off, &found);
1161                                 if ( ! found  && SSL_in_init(s))
1162                                         {
1163                                         /* fprintf( stderr,"in init = %d\n", SSL_in_init(s)); */
1164                                         /* requested a message not yet sent,
1165                                            send an alert ourselves */
1166                                         ssl3_send_alert(s,SSL3_AL_WARNING,
1167                                                 DTLS1_AD_MISSING_HANDSHAKE_MESSAGE);
1168                                         }
1169                                 }
1170 #endif
1171                         }
1172                 else if (alert_level == 2) /* fatal */
1173                         {
1174                         char tmp[16];
1175
1176                         s->rwstate=SSL_NOTHING;
1177                         s->s3->fatal_alert = alert_descr;
1178                         SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_AD_REASON_OFFSET + alert_descr);
1179                         BIO_snprintf(tmp,sizeof tmp,"%d",alert_descr);
1180                         ERR_add_error_data(2,"SSL alert number ",tmp);
1181                         s->shutdown|=SSL_RECEIVED_SHUTDOWN;
1182                         SSL_CTX_remove_session(s->ctx,s->session);
1183                         return(0);
1184                         }
1185                 else
1186                         {
1187                         al=SSL_AD_ILLEGAL_PARAMETER;
1188                         SSLerr(SSL_F_DTLS1_READ_BYTES,SSL_R_UNKNOWN_ALERT_TYPE);
1189                         goto f_err;
1190                         }
1191
1192                 goto start;
1193                 }
1194
1195         if (s->shutdown & SSL_SENT_SHUTDOWN) /* but we have not received a shutdown */
1196                 {
1197                 s->rwstate=SSL_NOTHING;
1198                 rr->length=0;
1199                 return(0);
1200                 }
1201
1202         if (rr->type == SSL3_RT_CHANGE_CIPHER_SPEC)
1203                 {
1204                 struct ccs_header_st ccs_hdr;
1205                 unsigned int ccs_hdr_len = DTLS1_CCS_HEADER_LENGTH;
1206
1207                 dtls1_get_ccs_header(rr->data, &ccs_hdr);
1208
1209                 if (s->version == DTLS1_BAD_VER)
1210                         ccs_hdr_len = 3;
1211
1212                 /* 'Change Cipher Spec' is just a single byte, so we know
1213                  * exactly what the record payload has to look like */
1214                 /* XDTLS: check that epoch is consistent */
1215                 if (    (rr->length != ccs_hdr_len) ||
1216                         (rr->off != 0) || (rr->data[0] != SSL3_MT_CCS))
1217                         {
1218                         i=SSL_AD_ILLEGAL_PARAMETER;
1219                         SSLerr(SSL_F_DTLS1_READ_BYTES,SSL_R_BAD_CHANGE_CIPHER_SPEC);
1220                         goto err;
1221                         }
1222
1223                 rr->length=0;
1224
1225                 if (s->msg_callback)
1226                         s->msg_callback(0, s->version, SSL3_RT_CHANGE_CIPHER_SPEC,
1227                                 rr->data, 1, s, s->msg_callback_arg);
1228
1229                 /* We can't process a CCS now, because previous handshake
1230                  * messages are still missing, so just drop it.
1231                  */
1232                 if (!s->d1->change_cipher_spec_ok)
1233                         {
1234                         goto start;
1235                         }
1236
1237                 s->d1->change_cipher_spec_ok = 0;
1238
1239                 s->s3->change_cipher_spec=1;
1240                 if (!ssl3_do_change_cipher_spec(s))
1241                         goto err;
1242
1243                 /* do this whenever CCS is processed */
1244                 dtls1_reset_seq_numbers(s, SSL3_CC_READ);
1245
1246                 if (s->version == DTLS1_BAD_VER)
1247                         s->d1->handshake_read_seq++;
1248
1249 #ifndef OPENSSL_NO_SCTP
1250                 /* Remember that a CCS has been received,
1251                  * so that an old key of SCTP-Auth can be
1252                  * deleted when a CCS is sent. Will be ignored
1253                  * if no SCTP is used
1254                  */
1255                 BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_AUTH_CCS_RCVD, 1, NULL);
1256 #endif
1257
1258                 goto start;
1259                 }
1260
1261         /* Unexpected handshake message (Client Hello, or protocol violation) */
1262         if ((s->d1->handshake_fragment_len >= DTLS1_HM_HEADER_LENGTH) &&
1263                 !s->in_handshake)
1264                 {
1265                 struct hm_header_st msg_hdr;
1266
1267                 /* this may just be a stale retransmit */
1268                 dtls1_get_message_header(rr->data, &msg_hdr);
1269                 if( rr->epoch != s->d1->r_epoch)
1270                         {
1271                         rr->length = 0;
1272                         goto start;
1273                         }
1274
1275                 /* If we are server, we may have a repeated FINISHED of the
1276                  * client here, then retransmit our CCS and FINISHED.
1277                  */
1278                 if (msg_hdr.type == SSL3_MT_FINISHED)
1279                         {
1280                         if (dtls1_check_timeout_num(s) < 0)
1281                                 return -1;
1282
1283                         dtls1_retransmit_buffered_messages(s);
1284                         rr->length = 0;
1285                         goto start;
1286                         }
1287
1288                 if (((s->state&SSL_ST_MASK) == SSL_ST_OK) &&
1289                         !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS))
1290                         {
1291 #if 0 /* worked only because C operator preferences are not as expected (and
1292        * because this is not really needed for clients except for detecting
1293        * protocol violations): */
1294                         s->state=SSL_ST_BEFORE|(s->server)
1295                                 ?SSL_ST_ACCEPT
1296                                 :SSL_ST_CONNECT;
1297 #else
1298                         s->state = s->server ? SSL_ST_ACCEPT : SSL_ST_CONNECT;
1299 #endif
1300                         s->renegotiate=1;
1301                         s->new_session=1;
1302                         }
1303                 i=s->handshake_func(s);
1304                 if (i < 0) return(i);
1305                 if (i == 0)
1306                         {
1307                         SSLerr(SSL_F_DTLS1_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
1308                         return(-1);
1309                         }
1310
1311                 if (!(s->mode & SSL_MODE_AUTO_RETRY))
1312                         {
1313                         if (s->s3->rbuf.left == 0) /* no read-ahead left? */
1314                                 {
1315                                 BIO *bio;
1316                                 /* In the case where we try to read application data,
1317                                  * but we trigger an SSL handshake, we return -1 with
1318                                  * the retry option set.  Otherwise renegotiation may
1319                                  * cause nasty problems in the blocking world */
1320                                 s->rwstate=SSL_READING;
1321                                 bio=SSL_get_rbio(s);
1322                                 BIO_clear_retry_flags(bio);
1323                                 BIO_set_retry_read(bio);
1324                                 return(-1);
1325                                 }
1326                         }
1327                 goto start;
1328                 }
1329
1330         switch (rr->type)
1331                 {
1332         default:
1333 #ifndef OPENSSL_NO_TLS
1334                 /* TLS just ignores unknown message types */
1335                 if (s->version == TLS1_VERSION)
1336                         {
1337                         rr->length = 0;
1338                         goto start;
1339                         }
1340 #endif
1341                 al=SSL_AD_UNEXPECTED_MESSAGE;
1342                 SSLerr(SSL_F_DTLS1_READ_BYTES,SSL_R_UNEXPECTED_RECORD);
1343                 goto f_err;
1344         case SSL3_RT_CHANGE_CIPHER_SPEC:
1345         case SSL3_RT_ALERT:
1346         case SSL3_RT_HANDSHAKE:
1347                 /* we already handled all of these, with the possible exception
1348                  * of SSL3_RT_HANDSHAKE when s->in_handshake is set, but that
1349                  * should not happen when type != rr->type */
1350                 al=SSL_AD_UNEXPECTED_MESSAGE;
1351                 SSLerr(SSL_F_DTLS1_READ_BYTES,ERR_R_INTERNAL_ERROR);
1352                 goto f_err;
1353         case SSL3_RT_APPLICATION_DATA:
1354                 /* At this point, we were expecting handshake data,
1355                  * but have application data.  If the library was
1356                  * running inside ssl3_read() (i.e. in_read_app_data
1357                  * is set) and it makes sense to read application data
1358                  * at this point (session renegotiation not yet started),
1359                  * we will indulge it.
1360                  */
1361                 if (s->s3->in_read_app_data &&
1362                         (s->s3->total_renegotiations != 0) &&
1363                         ((
1364                                 (s->state & SSL_ST_CONNECT) &&
1365                                 (s->state >= SSL3_ST_CW_CLNT_HELLO_A) &&
1366                                 (s->state <= SSL3_ST_CR_SRVR_HELLO_A)
1367                                 ) || (
1368                                         (s->state & SSL_ST_ACCEPT) &&
1369                                         (s->state <= SSL3_ST_SW_HELLO_REQ_A) &&
1370                                         (s->state >= SSL3_ST_SR_CLNT_HELLO_A)
1371                                         )
1372                                 ))
1373                         {
1374                         s->s3->in_read_app_data=2;
1375                         return(-1);
1376                         }
1377                 else
1378                         {
1379                         al=SSL_AD_UNEXPECTED_MESSAGE;
1380                         SSLerr(SSL_F_DTLS1_READ_BYTES,SSL_R_UNEXPECTED_RECORD);
1381                         goto f_err;
1382                         }
1383                 }
1384         /* not reached */
1385
1386 f_err:
1387         ssl3_send_alert(s,SSL3_AL_FATAL,al);
1388 err:
1389         return(-1);
1390         }
1391
1392 int
1393 dtls1_write_app_data_bytes(SSL *s, int type, const void *buf_, int len)
1394         {
1395         int i;
1396
1397 #ifndef OPENSSL_NO_SCTP
1398                 /* Check if we have to continue an interrupted handshake
1399                  * for reading belated app data with SCTP.
1400                  */
1401                 if ((SSL_in_init(s) && !s->in_handshake) ||
1402                     (BIO_dgram_is_sctp(SSL_get_wbio(s)) &&
1403                      (s->state == DTLS1_SCTP_ST_SR_READ_SOCK || s->state == DTLS1_SCTP_ST_CR_READ_SOCK)))
1404 #else
1405                 if (SSL_in_init(s) && !s->in_handshake)
1406 #endif
1407                 {
1408                 i=s->handshake_func(s);
1409                 if (i < 0) return(i);
1410                 if (i == 0)
1411                         {
1412                         SSLerr(SSL_F_DTLS1_WRITE_APP_DATA_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
1413                         return -1;
1414                         }
1415                 }
1416
1417         if (len > SSL3_RT_MAX_PLAIN_LENGTH)
1418                 {
1419                         SSLerr(SSL_F_DTLS1_WRITE_APP_DATA_BYTES,SSL_R_DTLS_MESSAGE_TOO_BIG);
1420                         return -1;
1421                 }
1422
1423         i = dtls1_write_bytes(s, type, buf_, len);
1424         return i;
1425         }
1426
1427
1428         /* this only happens when a client hello is received and a handshake
1429          * is started. */
1430 static int
1431 have_handshake_fragment(SSL *s, int type, unsigned char *buf,
1432         int len, int peek)
1433         {
1434
1435         if ((type == SSL3_RT_HANDSHAKE) && (s->d1->handshake_fragment_len > 0))
1436                 /* (partially) satisfy request from storage */
1437                 {
1438                 unsigned char *src = s->d1->handshake_fragment;
1439                 unsigned char *dst = buf;
1440                 unsigned int k,n;
1441
1442                 /* peek == 0 */
1443                 n = 0;
1444                 while ((len > 0) && (s->d1->handshake_fragment_len > 0))
1445                         {
1446                         *dst++ = *src++;
1447                         len--; s->d1->handshake_fragment_len--;
1448                         n++;
1449                         }
1450                 /* move any remaining fragment bytes: */
1451                 for (k = 0; k < s->d1->handshake_fragment_len; k++)
1452                         s->d1->handshake_fragment[k] = *src++;
1453                 return n;
1454                 }
1455
1456         return 0;
1457         }
1458
1459
1460
1461
1462 /* Call this to write data in records of type 'type'
1463  * It will return <= 0 if not all data has been sent or non-blocking IO.
1464  */
1465 int dtls1_write_bytes(SSL *s, int type, const void *buf, int len)
1466         {
1467         int i;
1468
1469         OPENSSL_assert(len <= SSL3_RT_MAX_PLAIN_LENGTH);
1470         s->rwstate=SSL_NOTHING;
1471         i=do_dtls1_write(s, type, buf, len, 0);
1472         return i;
1473         }
1474
1475 int do_dtls1_write(SSL *s, int type, const unsigned char *buf, unsigned int len, int create_empty_fragment)
1476         {
1477         unsigned char *p,*pseq;
1478         int i,mac_size,clear=0;
1479         int prefix_len = 0;
1480         SSL3_RECORD *wr;
1481         SSL3_BUFFER *wb;
1482         SSL_SESSION *sess;
1483         int bs;
1484
1485         /* first check if there is a SSL3_BUFFER still being written
1486          * out.  This will happen with non blocking IO */
1487         if (s->s3->wbuf.left != 0)
1488                 {
1489                 OPENSSL_assert(0); /* XDTLS:  want to see if we ever get here */
1490                 return(ssl3_write_pending(s,type,buf,len));
1491                 }
1492
1493         /* If we have an alert to send, lets send it */
1494         if (s->s3->alert_dispatch)
1495                 {
1496                 i=s->method->ssl_dispatch_alert(s);
1497                 if (i <= 0)
1498                         return(i);
1499                 /* if it went, fall through and send more stuff */
1500                 }
1501
1502         if (len == 0 && !create_empty_fragment)
1503                 return 0;
1504
1505         wr= &(s->s3->wrec);
1506         wb= &(s->s3->wbuf);
1507         sess=s->session;
1508
1509         if (    (sess == NULL) ||
1510                 (s->enc_write_ctx == NULL) ||
1511                 (EVP_MD_CTX_md(s->write_hash) == NULL))
1512                 clear=1;
1513
1514         if (clear)
1515                 mac_size=0;
1516         else
1517                 {
1518                 mac_size=EVP_MD_CTX_size(s->write_hash);
1519                 if (mac_size < 0)
1520                         goto err;
1521                 }
1522
1523         /* DTLS implements explicit IV, so no need for empty fragments */
1524 #if 0
1525         /* 'create_empty_fragment' is true only when this function calls itself */
1526         if (!clear && !create_empty_fragment && !s->s3->empty_fragment_done
1527             && SSL_version(s) != DTLS1_VERSION && SSL_version(s) != DTLS1_BAD_VER)
1528                 {
1529                 /* countermeasure against known-IV weakness in CBC ciphersuites
1530                  * (see http://www.openssl.org/~bodo/tls-cbc.txt)
1531                  */
1532
1533                 if (s->s3->need_empty_fragments && type == SSL3_RT_APPLICATION_DATA)
1534                         {
1535                         /* recursive function call with 'create_empty_fragment' set;
1536                          * this prepares and buffers the data for an empty fragment
1537                          * (these 'prefix_len' bytes are sent out later
1538                          * together with the actual payload) */
1539                         prefix_len = s->method->do_ssl_write(s, type, buf, 0, 1);
1540                         if (prefix_len <= 0)
1541                                 goto err;
1542
1543                         if (s->s3->wbuf.len < (size_t)prefix_len + SSL3_RT_MAX_PACKET_SIZE)
1544                                 {
1545                                 /* insufficient space */
1546                                 SSLerr(SSL_F_DO_DTLS1_WRITE, ERR_R_INTERNAL_ERROR);
1547                                 goto err;
1548                                 }
1549                         }
1550
1551                 s->s3->empty_fragment_done = 1;
1552                 }
1553 #endif
1554         p = wb->buf + prefix_len;
1555
1556         /* write the header */
1557
1558         *(p++)=type&0xff;
1559         wr->type=type;
1560
1561         *(p++)=(s->version>>8);
1562         *(p++)=s->version&0xff;
1563
1564         /* field where we are to write out packet epoch, seq num and len */
1565         pseq=p;
1566         p+=10;
1567
1568         /* lets setup the record stuff. */
1569
1570         /* Make space for the explicit IV in case of CBC.
1571          * (this is a bit of a boundary violation, but what the heck).
1572          */
1573         if ( s->enc_write_ctx &&
1574                 (EVP_CIPHER_mode( s->enc_write_ctx->cipher ) & EVP_CIPH_CBC_MODE))
1575                 bs = EVP_CIPHER_block_size(s->enc_write_ctx->cipher);
1576         else
1577                 bs = 0;
1578
1579         wr->data=p + bs;  /* make room for IV in case of CBC */
1580         wr->length=(int)len;
1581         wr->input=(unsigned char *)buf;
1582
1583         /* we now 'read' from wr->input, wr->length bytes into
1584          * wr->data */
1585
1586         /* first we compress */
1587         if (s->compress != NULL)
1588                 {
1589                 if (!ssl3_do_compress(s))
1590                         {
1591                         SSLerr(SSL_F_DO_DTLS1_WRITE,SSL_R_COMPRESSION_FAILURE);
1592                         goto err;
1593                         }
1594                 }
1595         else
1596                 {
1597                 memcpy(wr->data,wr->input,wr->length);
1598                 wr->input=wr->data;
1599                 }
1600
1601         /* we should still have the output to wr->data and the input
1602          * from wr->input.  Length should be wr->length.
1603          * wr->data still points in the wb->buf */
1604
1605         if (mac_size != 0)
1606                 {
1607                 if(s->method->ssl3_enc->mac(s,&(p[wr->length + bs]),1) < 0)
1608                         goto err;
1609                 wr->length+=mac_size;
1610                 }
1611
1612         /* this is true regardless of mac size */
1613         wr->input=p;
1614         wr->data=p;
1615
1616
1617         /* ssl3_enc can only have an error on read */
1618         if (bs) /* bs != 0 in case of CBC */
1619                 {
1620                 RAND_pseudo_bytes(p,bs);
1621                 /* master IV and last CBC residue stand for
1622                  * the rest of randomness */
1623                 wr->length += bs;
1624                 }
1625
1626         s->method->ssl3_enc->enc(s,1);
1627
1628         /* record length after mac and block padding */
1629 /*      if (type == SSL3_RT_APPLICATION_DATA ||
1630         (type == SSL3_RT_ALERT && ! SSL_in_init(s))) */
1631
1632         /* there's only one epoch between handshake and app data */
1633
1634         s2n(s->d1->w_epoch, pseq);
1635
1636         /* XDTLS: ?? */
1637 /*      else
1638         s2n(s->d1->handshake_epoch, pseq); */
1639
1640         memcpy(pseq, &(s->s3->write_sequence[2]), 6);
1641         pseq+=6;
1642         s2n(wr->length,pseq);
1643
1644         /* we should now have
1645          * wr->data pointing to the encrypted data, which is
1646          * wr->length long */
1647         wr->type=type; /* not needed but helps for debugging */
1648         wr->length+=DTLS1_RT_HEADER_LENGTH;
1649
1650 #if 0  /* this is now done at the message layer */
1651         /* buffer the record, making it easy to handle retransmits */
1652         if ( type == SSL3_RT_HANDSHAKE || type == SSL3_RT_CHANGE_CIPHER_SPEC)
1653                 dtls1_buffer_record(s, wr->data, wr->length,
1654                         *((PQ_64BIT *)&(s->s3->write_sequence[0])));
1655 #endif
1656
1657         ssl3_record_sequence_update(&(s->s3->write_sequence[0]));
1658
1659         if (create_empty_fragment)
1660                 {
1661                 /* we are in a recursive call;
1662                  * just return the length, don't write out anything here
1663                  */
1664                 return wr->length;
1665                 }
1666
1667         /* now let's set up wb */
1668         wb->left = prefix_len + wr->length;
1669         wb->offset = 0;
1670
1671         /* memorize arguments so that ssl3_write_pending can detect bad write retries later */
1672         s->s3->wpend_tot=len;
1673         s->s3->wpend_buf=buf;
1674         s->s3->wpend_type=type;
1675         s->s3->wpend_ret=len;
1676
1677         /* we now just need to write the buffer */
1678         return ssl3_write_pending(s,type,buf,len);
1679 err:
1680         return -1;
1681         }
1682
1683
1684
1685 static int dtls1_record_replay_check(SSL *s, DTLS1_BITMAP *bitmap)
1686         {
1687         int cmp;
1688         unsigned int shift;
1689         const unsigned char *seq = s->s3->read_sequence;
1690
1691         cmp = satsub64be(seq,bitmap->max_seq_num);
1692         if (cmp > 0)
1693                 {
1694                 memcpy (s->s3->rrec.seq_num,seq,8);
1695                 return 1; /* this record in new */
1696                 }
1697         shift = -cmp;
1698         if (shift >= sizeof(bitmap->map)*8)
1699                 return 0; /* stale, outside the window */
1700         else if (bitmap->map & (1UL<<shift))
1701                 return 0; /* record previously received */
1702
1703         memcpy (s->s3->rrec.seq_num,seq,8);
1704         return 1;
1705         }
1706
1707
1708 static void dtls1_record_bitmap_update(SSL *s, DTLS1_BITMAP *bitmap)
1709         {
1710         int cmp;
1711         unsigned int shift;
1712         const unsigned char *seq = s->s3->read_sequence;
1713
1714         cmp = satsub64be(seq,bitmap->max_seq_num);
1715         if (cmp > 0)
1716                 {
1717                 shift = cmp;
1718                 if (shift < sizeof(bitmap->map)*8)
1719                         bitmap->map <<= shift, bitmap->map |= 1UL;
1720                 else
1721                         bitmap->map = 1UL;
1722                 memcpy(bitmap->max_seq_num,seq,8);
1723                 }
1724         else    {
1725                 shift = -cmp;
1726                 if (shift < sizeof(bitmap->map)*8)
1727                         bitmap->map |= 1UL<<shift;
1728                 }
1729         }
1730
1731
1732 int dtls1_dispatch_alert(SSL *s)
1733         {
1734         int i,j;
1735         void (*cb)(const SSL *ssl,int type,int val)=NULL;
1736         unsigned char buf[DTLS1_AL_HEADER_LENGTH];
1737         unsigned char *ptr = &buf[0];
1738
1739         s->s3->alert_dispatch=0;
1740
1741         memset(buf, 0x00, sizeof(buf));
1742         *ptr++ = s->s3->send_alert[0];
1743         *ptr++ = s->s3->send_alert[1];
1744
1745 #ifdef DTLS1_AD_MISSING_HANDSHAKE_MESSAGE
1746         if (s->s3->send_alert[1] == DTLS1_AD_MISSING_HANDSHAKE_MESSAGE)
1747                 {
1748                 s2n(s->d1->handshake_read_seq, ptr);
1749 #if 0
1750                 if ( s->d1->r_msg_hdr.frag_off == 0)  /* waiting for a new msg */
1751
1752                 else
1753                         s2n(s->d1->r_msg_hdr.seq, ptr); /* partial msg read */
1754 #endif
1755
1756 #if 0
1757                 fprintf(stderr, "s->d1->handshake_read_seq = %d, s->d1->r_msg_hdr.seq = %d\n",s->d1->handshake_read_seq,s->d1->r_msg_hdr.seq);
1758 #endif
1759                 l2n3(s->d1->r_msg_hdr.frag_off, ptr);
1760                 }
1761 #endif
1762
1763         i = do_dtls1_write(s, SSL3_RT_ALERT, &buf[0], sizeof(buf), 0);
1764         if (i <= 0)
1765                 {
1766                 s->s3->alert_dispatch=1;
1767                 /* fprintf( stderr, "not done with alert\n" ); */
1768                 }
1769         else
1770                 {
1771                 if (s->s3->send_alert[0] == SSL3_AL_FATAL
1772 #ifdef DTLS1_AD_MISSING_HANDSHAKE_MESSAGE
1773                     || s->s3->send_alert[1] == DTLS1_AD_MISSING_HANDSHAKE_MESSAGE
1774 #endif
1775                     )
1776                         (void)BIO_flush(s->wbio);
1777
1778                 if (s->msg_callback)
1779                         s->msg_callback(1, s->version, SSL3_RT_ALERT, s->s3->send_alert,
1780                                 2, s, s->msg_callback_arg);
1781
1782                 if (s->info_callback != NULL)
1783                         cb=s->info_callback;
1784                 else if (s->ctx->info_callback != NULL)
1785                         cb=s->ctx->info_callback;
1786
1787                 if (cb != NULL)
1788                         {
1789                         j=(s->s3->send_alert[0]<<8)|s->s3->send_alert[1];
1790                         cb(s,SSL_CB_WRITE_ALERT,j);
1791                         }
1792                 }
1793         return(i);
1794         }
1795
1796
1797 static DTLS1_BITMAP *
1798 dtls1_get_bitmap(SSL *s, SSL3_RECORD *rr, unsigned int *is_next_epoch)
1799     {
1800
1801     *is_next_epoch = 0;
1802
1803     /* In current epoch, accept HM, CCS, DATA, & ALERT */
1804     if (rr->epoch == s->d1->r_epoch)
1805         return &s->d1->bitmap;
1806
1807     /* Only HM and ALERT messages can be from the next epoch */
1808     else if (rr->epoch == (unsigned long)(s->d1->r_epoch + 1) &&
1809         (rr->type == SSL3_RT_HANDSHAKE ||
1810             rr->type == SSL3_RT_ALERT))
1811         {
1812         *is_next_epoch = 1;
1813         return &s->d1->next_bitmap;
1814         }
1815
1816     return NULL;
1817     }
1818
1819 #if 0
1820 static int
1821 dtls1_record_needs_buffering(SSL *s, SSL3_RECORD *rr, unsigned short *priority,
1822         unsigned long *offset)
1823         {
1824
1825         /* alerts are passed up immediately */
1826         if ( rr->type == SSL3_RT_APPLICATION_DATA ||
1827                 rr->type == SSL3_RT_ALERT)
1828                 return 0;
1829
1830         /* Only need to buffer if a handshake is underway.
1831          * (this implies that Hello Request and Client Hello are passed up
1832          * immediately) */
1833         if ( SSL_in_init(s))
1834                 {
1835                 unsigned char *data = rr->data;
1836                 /* need to extract the HM/CCS sequence number here */
1837                 if ( rr->type == SSL3_RT_HANDSHAKE ||
1838                         rr->type == SSL3_RT_CHANGE_CIPHER_SPEC)
1839                         {
1840                         unsigned short seq_num;
1841                         struct hm_header_st msg_hdr;
1842                         struct ccs_header_st ccs_hdr;
1843
1844                         if ( rr->type == SSL3_RT_HANDSHAKE)
1845                                 {
1846                                 dtls1_get_message_header(data, &msg_hdr);
1847                                 seq_num = msg_hdr.seq;
1848                                 *offset = msg_hdr.frag_off;
1849                                 }
1850                         else
1851                                 {
1852                                 dtls1_get_ccs_header(data, &ccs_hdr);
1853                                 seq_num = ccs_hdr.seq;
1854                                 *offset = 0;
1855                                 }
1856
1857                         /* this is either a record we're waiting for, or a
1858                          * retransmit of something we happened to previously
1859                          * receive (higher layers will drop the repeat silently */
1860                         if ( seq_num < s->d1->handshake_read_seq)
1861                                 return 0;
1862                         if (rr->type == SSL3_RT_HANDSHAKE &&
1863                                 seq_num == s->d1->handshake_read_seq &&
1864                                 msg_hdr.frag_off < s->d1->r_msg_hdr.frag_off)
1865                                 return 0;
1866                         else if ( seq_num == s->d1->handshake_read_seq &&
1867                                 (rr->type == SSL3_RT_CHANGE_CIPHER_SPEC ||
1868                                         msg_hdr.frag_off == s->d1->r_msg_hdr.frag_off))
1869                                 return 0;
1870                         else
1871                                 {
1872                                 *priority = seq_num;
1873                                 return 1;
1874                                 }
1875                         }
1876                 else /* unknown record type */
1877                         return 0;
1878                 }
1879
1880         return 0;
1881         }
1882 #endif
1883
1884 void
1885 dtls1_reset_seq_numbers(SSL *s, int rw)
1886         {
1887         unsigned char *seq;
1888         unsigned int seq_bytes = sizeof(s->s3->read_sequence);
1889
1890         if ( rw & SSL3_CC_READ)
1891                 {
1892                 seq = s->s3->read_sequence;
1893                 s->d1->r_epoch++;
1894                 memcpy(&(s->d1->bitmap), &(s->d1->next_bitmap), sizeof(DTLS1_BITMAP));
1895                 memset(&(s->d1->next_bitmap), 0x00, sizeof(DTLS1_BITMAP));
1896                 }
1897         else
1898                 {
1899                 seq = s->s3->write_sequence;
1900                 memcpy(s->d1->last_write_sequence, seq, sizeof(s->s3->write_sequence));
1901                 s->d1->w_epoch++;
1902                 }
1903
1904         memset(seq, 0x00, seq_bytes);
1905         }