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                 OPENSSL_free(rdata);
 251                 pitem_free(item);
 252                 return(0);
 253                 }
 254
 255         /* insert should not fail, since duplicates are dropped */
 256         if (pqueue_insert(queue->q, item) == NULL)
 257                 {
 258                 SSLerr(SSL_F_DTLS1_BUFFER_RECORD, ERR_R_INTERNAL_ERROR);
 259                 OPENSSL_free(rdata);
 260                 pitem_free(item);
 261                 return(0);
 262                 }
 263
 264         return(1);
 265         }
 266
 267
 268 static int
 269 dtls1_retrieve_buffered_record(SSL *s, record_pqueue *queue)
 270     {
 271     pitem *item;
 272
 273     item = pqueue_pop(queue->q);
 274     if (item)
 275         {
 276         dtls1_copy_record(s, item);
 277
 278         OPENSSL_free(item->data);
 279                 pitem_free(item);
 280
 281         return(1);
 282         }
 283
 284     return(0);
 285     }
 286
 287
 288 /* retrieve a buffered record that belongs to the new epoch, i.e., not processed
 289  * yet */
 290 #define dtls1_get_unprocessed_record(s) \
 291                    dtls1_retrieve_buffered_record((s), \
 292                    &((s)->d1->unprocessed_rcds))
 293
 294 /* retrieve a buffered record that belongs to the current epoch, ie, processed */
 295 #define dtls1_get_processed_record(s) \
 296                    dtls1_retrieve_buffered_record((s), \
 297                    &((s)->d1->processed_rcds))
 298
 299 static int
 300 dtls1_process_buffered_records(SSL *s)
 301     {
 302     pitem *item;
 303
 304     item = pqueue_peek(s->d1->unprocessed_rcds.q);
 305     if (item)
 306         {
 307         /* Check if epoch is current. */
 308         if (s->d1->unprocessed_rcds.epoch != s->d1->r_epoch)
 309             return(1);  /* Nothing to do. */
 310
 311         /* Process all the records. */
 312         while (pqueue_peek(s->d1->unprocessed_rcds.q))
 313             {
 314             dtls1_get_unprocessed_record(s);
 315             if ( ! dtls1_process_record(s))
 316                 return(0);
 317             dtls1_buffer_record(s, &(s->d1->processed_rcds),
 318                 s->s3->rrec.seq_num);
 319             }
 320         }
 321
 322     /* sync epoch numbers once all the unprocessed records
 323      * have been processed */
 324     s->d1->processed_rcds.epoch = s->d1->r_epoch;
 325     s->d1->unprocessed_rcds.epoch = s->d1->r_epoch + 1;
 326
 327     return(1);
 328     }
 329
 330
 331 #if 0
 332
 333 static int
 334 dtls1_get_buffered_record(SSL *s)
 335         {
 336         pitem *item;
 337         PQ_64BIT priority =
 338                 (((PQ_64BIT)s->d1->handshake_read_seq) << 32) |
 339                 ((PQ_64BIT)s->d1->r_msg_hdr.frag_off);
 340
 341         if ( ! SSL_in_init(s))  /* if we're not (re)negotiating,
 342                                                            nothing buffered */
 343                 return 0;
 344
 345
 346         item = pqueue_peek(s->d1->rcvd_records);
 347         if (item && item->priority == priority)
 348                 {
 349                 /* Check if we've received the record of interest.  It must be
 350                  * a handshake record, since data records as passed up without
 351                  * buffering */
 352                 DTLS1_RECORD_DATA *rdata;
 353                 item = pqueue_pop(s->d1->rcvd_records);
 354                 rdata = (DTLS1_RECORD_DATA *)item->data;
 355
 356                 if (s->s3->rbuf.buf != NULL)
 357                         OPENSSL_free(s->s3->rbuf.buf);
 358
 359                 s->packet = rdata->packet;
 360                 s->packet_length = rdata->packet_length;
 361                 memcpy(&(s->s3->rbuf), &(rdata->rbuf), sizeof(SSL3_BUFFER));
 362                 memcpy(&(s->s3->rrec), &(rdata->rrec), sizeof(SSL3_RECORD));
 363
 364                 OPENSSL_free(item->data);
 365                 pitem_free(item);
 366
 367                 /* s->d1->next_expected_seq_num++; */
 368                 return(1);
 369                 }
 370
 371         return 0;
 372         }
 373
 374 #endif
 375
 376 static int
 377 dtls1_process_record(SSL *s)
 378 {
 379         int i,al;
 380         int enc_err;
 381         SSL_SESSION *sess;
 382         SSL3_RECORD *rr;
 383         unsigned int mac_size, orig_len;
 384         unsigned char md[EVP_MAX_MD_SIZE];
 385
 386         rr= &(s->s3->rrec);
 387         sess = s->session;
 388
 389         /* At this point, s->packet_length == SSL3_RT_HEADER_LNGTH + rr->length,
 390          * and we have that many bytes in s->packet
 391          */
 392         rr->input= &(s->packet[DTLS1_RT_HEADER_LENGTH]);
 393
 394         /* ok, we can now read from 's->packet' data into 'rr'
 395          * rr->input points at rr->length bytes, which
 396          * need to be copied into rr->data by either
 397          * the decryption or by the decompression
 398          * When the data is 'copied' into the rr->data buffer,
 399          * rr->input will be pointed at the new buffer */
 400
 401         /* We now have - encrypted [ MAC [ compressed [ plain ] ] ]
 402          * rr->length bytes of encrypted compressed stuff. */
 403
 404         /* check is not needed I believe */
 405         if (rr->length > SSL3_RT_MAX_ENCRYPTED_LENGTH)
 406                 {
 407                 al=SSL_AD_RECORD_OVERFLOW;
 408                 SSLerr(SSL_F_DTLS1_PROCESS_RECORD,SSL_R_ENCRYPTED_LENGTH_TOO_LONG);
 409                 goto f_err;
 410                 }
 411
 412         /* decrypt in place in 'rr->input' */
 413         rr->data=rr->input;
 414
 415         enc_err = s->method->ssl3_enc->enc(s,0);
 416         /* enc_err is:
 417          *    0: (in non-constant time) if the record is publically invalid.
 418          *    1: if the padding is valid
 419          *    -1: if the padding is invalid */
 420         if (enc_err == 0)
 421                 {
 422                 /* For DTLS we simply ignore bad packets. */
 423                 rr->length = 0;
 424                 s->packet_length = 0;
 425                 goto err;
 426                 }
 427
 428 #ifdef TLS_DEBUG
 429 printf("dec %d\n",rr->length);
 430 { unsigned int z; for (z=0; z<rr->length; z++) printf("%02X%c",rr->data[z],((z+1)%16)?' ':'\n'); }
 431 printf("\n");
 432 #endif
 433
 434         /* r->length is now the compressed data plus mac */
 435         if ((sess != NULL) &&
 436             (s->enc_read_ctx != NULL) &&
 437             (EVP_MD_CTX_md(s->read_hash) != NULL))
 438                 {
 439                 /* s->read_hash != NULL => mac_size != -1 */
 440                 unsigned char *mac = NULL;
 441                 unsigned char mac_tmp[EVP_MAX_MD_SIZE];
 442                 mac_size=EVP_MD_CTX_size(s->read_hash);
 443                 OPENSSL_assert(mac_size <= EVP_MAX_MD_SIZE);
 444
 445                 /* kludge: *_cbc_remove_padding passes padding length in rr->type */
 446                 orig_len = rr->length+((unsigned int)rr->type>>8);
 447
 448                 /* orig_len is the length of the record before any padding was
 449                  * removed. This is public information, as is the MAC in use,
 450                  * therefore we can safely process the record in a different
 451                  * amount of time if it's too short to possibly contain a MAC.
 452                  */
 453                 if (orig_len < mac_size ||
 454                     /* CBC records must have a padding length byte too. */
 455                     (EVP_CIPHER_CTX_mode(s->enc_read_ctx) == EVP_CIPH_CBC_MODE &&
 456                      orig_len < mac_size+1))
 457                         {
 458                         al=SSL_AD_DECODE_ERROR;
 459                         SSLerr(SSL_F_DTLS1_PROCESS_RECORD,SSL_R_LENGTH_TOO_SHORT);
 460                         goto f_err;
 461                         }
 462
 463                 if (EVP_CIPHER_CTX_mode(s->enc_read_ctx) == EVP_CIPH_CBC_MODE)
 464                         {
 465                         /* We update the length so that the TLS header bytes
 466                          * can be constructed correctly but we need to extract
 467                          * the MAC in constant time from within the record,
 468                          * without leaking the contents of the padding bytes.
 469                          * */
 470                         mac = mac_tmp;
 471                         ssl3_cbc_copy_mac(mac_tmp, rr, mac_size, orig_len);
 472                         rr->length -= mac_size;
 473                         }
 474                 else
 475                         {
 476                         /* In this case there's no padding, so |orig_len|
 477                          * equals |rec->length| and we checked that there's
 478                          * enough bytes for |mac_size| above. */
 479                         rr->length -= mac_size;
 480                         mac = &rr->data[rr->length];
 481                         }
 482
 483                 i=s->method->ssl3_enc->mac(s,md,0 /* not send */);
 484                 if (i < 0 || mac == NULL || CRYPTO_memcmp(md, mac, (size_t)mac_size) != 0)
 485                         enc_err = -1;
 486                 if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH+mac_size)
 487                         enc_err = -1;
 488                 }
 489
 490         if (enc_err < 0)
 491                 {
 492                 /* decryption failed, silently discard message */
 493                 rr->length = 0;
 494                 s->packet_length = 0;
 495                 goto err;
 496                 }
 497
 498         /* r->length is now just compressed */
 499         if (s->expand != NULL)
 500                 {
 501                 if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH)
 502                         {
 503                         al=SSL_AD_RECORD_OVERFLOW;
 504                         SSLerr(SSL_F_DTLS1_PROCESS_RECORD,SSL_R_COMPRESSED_LENGTH_TOO_LONG);
 505                         goto f_err;
 506                         }
 507                 if (!ssl3_do_uncompress(s))
 508                         {
 509                         al=SSL_AD_DECOMPRESSION_FAILURE;
 510                         SSLerr(SSL_F_DTLS1_PROCESS_RECORD,SSL_R_BAD_DECOMPRESSION);
 511                         goto f_err;
 512                         }
 513                 }
 514
 515         if (rr->length > SSL3_RT_MAX_PLAIN_LENGTH)
 516                 {
 517                 al=SSL_AD_RECORD_OVERFLOW;
 518                 SSLerr(SSL_F_DTLS1_PROCESS_RECORD,SSL_R_DATA_LENGTH_TOO_LONG);
 519                 goto f_err;
 520                 }
 521
 522         rr->off=0;
 523         /* So at this point the following is true
 524          * ssl->s3->rrec.type   is the type of record
 525          * ssl->s3->rrec.length == number of bytes in record
 526          * ssl->s3->rrec.off    == offset to first valid byte
 527          * ssl->s3->rrec.data   == where to take bytes from, increment
 528          *                         after use :-).
 529          */
 530
 531         /* we have pulled in a full packet so zero things */
 532         s->packet_length=0;
 533         dtls1_record_bitmap_update(s, &(s->d1->bitmap));/* Mark receipt of record. */
 534         return(1);
 535
 536 f_err:
 537         ssl3_send_alert(s,SSL3_AL_FATAL,al);
 538 err:
 539         return(0);
 540 }
 541
 542
 543 /* Call this to get a new input record.
 544  * It will return <= 0 if more data is needed, normally due to an error
 545  * or non-blocking IO.
 546  * When it finishes, one packet has been decoded and can be found in
 547  * ssl->s3->rrec.type    - is the type of record
 548  * ssl->s3->rrec.data,   - data
 549  * ssl->s3->rrec.length, - number of bytes
 550  */
 551 /* used only by dtls1_read_bytes */
 552 int dtls1_get_record(SSL *s)
 553         {
 554         int ssl_major,ssl_minor;
 555         int i,n;
 556         SSL3_RECORD *rr;
 557         unsigned char *p = NULL;
 558         unsigned short version;
 559         DTLS1_BITMAP *bitmap;
 560         unsigned int is_next_epoch;
 561
 562         rr= &(s->s3->rrec);
 563
 564         /* The epoch may have changed.  If so, process all the
 565          * pending records.  This is a non-blocking operation. */
 566         dtls1_process_buffered_records(s);
 567
 568         /* if we're renegotiating, then there may be buffered records */
 569         if (dtls1_get_processed_record(s))
 570                 return 1;
 571
 572         /* get something from the wire */
 573 again:
 574         /* check if we have the header */
 575         if (    (s->rstate != SSL_ST_READ_BODY) ||
 576                 (s->packet_length < DTLS1_RT_HEADER_LENGTH))
 577                 {
 578                 n=ssl3_read_n(s, DTLS1_RT_HEADER_LENGTH, s->s3->rbuf.len, 0);
 579                 /* read timeout is handled by dtls1_read_bytes */
 580                 if (n <= 0) return(n); /* error or non-blocking */
 581
 582                 /* this packet contained a partial record, dump it */
 583                 if (s->packet_length != DTLS1_RT_HEADER_LENGTH)
 584                         {
 585                         s->packet_length = 0;
 586                         goto again;
 587                         }
 588
 589                 s->rstate=SSL_ST_READ_BODY;
 590
 591                 p=s->packet;
 592
 593                 if (s->msg_callback)
 594                         s->msg_callback(0, 0, SSL3_RT_HEADER, p, DTLS1_RT_HEADER_LENGTH, s, s->msg_callback_arg);
 595
 596                 /* Pull apart the header into the DTLS1_RECORD */
 597                 rr->type= *(p++);
 598                 ssl_major= *(p++);
 599                 ssl_minor= *(p++);
 600                 version=(ssl_major<<8)|ssl_minor;
 601
 602                 /* sequence number is 64 bits, with top 2 bytes = epoch */
 603                 n2s(p,rr->epoch);
 604
 605                 memcpy(&(s->s3->read_sequence[2]), p, 6);
 606                 p+=6;
 607
 608                 n2s(p,rr->length);
 609
 610                 /* Lets check version */
 611                 if (!s->first_packet)
 612                         {
 613                         if (version != s->version)
 614                                 {
 615                                 /* unexpected version, silently discard */
 616                                 rr->length = 0;
 617                                 s->packet_length = 0;
 618                                 goto again;
 619                                 }
 620                         }
 621
 622                 if ((version & 0xff00) != (s->version & 0xff00))
 623                         {
 624                         /* wrong version, silently discard record */
 625                         rr->length = 0;
 626                         s->packet_length = 0;
 627                         goto again;
 628                         }
 629
 630                 if (rr->length > SSL3_RT_MAX_ENCRYPTED_LENGTH)
 631                         {
 632                         /* record too long, silently discard it */
 633                         rr->length = 0;
 634                         s->packet_length = 0;
 635                         goto again;
 636                         }
 637
 638                 /* now s->rstate == SSL_ST_READ_BODY */
 639                 }
 640
 641         /* s->rstate == SSL_ST_READ_BODY, get and decode the data */
 642
 643         if (rr->length > s->packet_length-DTLS1_RT_HEADER_LENGTH)
 644                 {
 645                 /* now s->packet_length == DTLS1_RT_HEADER_LENGTH */
 646                 i=rr->length;
 647                 n=ssl3_read_n(s,i,i,1);
 648                 if (n <= 0) return(n); /* error or non-blocking io */
 649
 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                     *p == SSL3_MT_CLIENT_HELLO) &&
 685                     !dtls1_record_replay_check(s, bitmap))
 686                         {
 687                         rr->length = 0;
 688                         s->packet_length=0; /* dump this record */
 689                         goto again;     /* get another record */
 690                         }
 691 #ifndef OPENSSL_NO_SCTP
 692                 }
 693 #endif
 694
 695         /* just read a 0 length packet */
 696         if (rr->length == 0) goto again;
 697
 698         /* If this record is from the next epoch (either HM or ALERT),
 699          * and a handshake is currently in progress, buffer it since it
 700          * cannot be processed at this time. However, do not buffer
 701          * anything while listening.
 702          */
 703         if (is_next_epoch)
 704                 {
 705                 if ((SSL_in_init(s) || s->in_handshake) && !s->d1->listen)
 706                         {
 707                         dtls1_buffer_record(s, &(s->d1->unprocessed_rcds), rr->seq_num);
 708                         }
 709                 rr->length = 0;
 710                 s->packet_length = 0;
 711                 goto again;
 712                 }
 713
 714         if (!dtls1_process_record(s))
 715                 {
 716                 rr->length = 0;
 717                 s->packet_length = 0;  /* dump this record */
 718                 goto again;   /* get another record */
 719                 }
 720
 721         return(1);
 722
 723         }
 724
 725 /* Return up to 'len' payload bytes received in 'type' records.
 726  * 'type' is one of the following:
 727  *
 728  *   -  SSL3_RT_HANDSHAKE (when ssl3_get_message calls us)
 729  *   -  SSL3_RT_APPLICATION_DATA (when ssl3_read calls us)
 730  *   -  0 (during a shutdown, no data has to be returned)
 731  *
 732  * If we don't have stored data to work from, read a SSL/TLS record first
 733  * (possibly multiple records if we still don't have anything to return).
 734  *
 735  * This function must handle any surprises the peer may have for us, such as
 736  * Alert records (e.g. close_notify), ChangeCipherSpec records (not really
 737  * a surprise, but handled as if it were), or renegotiation requests.
 738  * Also if record payloads contain fragments too small to process, we store
 739  * them until there is enough for the respective protocol (the record protocol
 740  * may use arbitrary fragmentation and even interleaving):
 741  *     Change cipher spec protocol
 742  *             just 1 byte needed, no need for keeping anything stored
 743  *     Alert protocol
 744  *             2 bytes needed (AlertLevel, AlertDescription)
 745  *     Handshake protocol
 746  *             4 bytes needed (HandshakeType, uint24 length) -- we just have
 747  *             to detect unexpected Client Hello and Hello Request messages
 748  *             here, anything else is handled by higher layers
 749  *     Application data protocol
 750  *             none of our business
 751  */
 752 int dtls1_read_bytes(SSL *s, int type, unsigned char *buf, int len, int peek)
 753         {
 754         int al,i,j,ret;
 755         unsigned int n;
 756         SSL3_RECORD *rr;
 757         void (*cb)(const SSL *ssl,int type2,int val)=NULL;
 758
 759         if (s->s3->rbuf.buf == NULL) /* Not initialized yet */
 760                 if (!ssl3_setup_buffers(s))
 761                         return(-1);
 762
 763     /* XXX: check what the second '&& type' is about */
 764         if ((type && (type != SSL3_RT_APPLICATION_DATA) &&
 765                 (type != SSL3_RT_HANDSHAKE) && type) ||
 766             (peek && (type != SSL3_RT_APPLICATION_DATA)))
 767                 {
 768                 SSLerr(SSL_F_DTLS1_READ_BYTES, ERR_R_INTERNAL_ERROR);
 769                 return -1;
 770                 }
 771
 772         /* check whether there's a handshake message (client hello?) waiting */
 773         if ( (ret = have_handshake_fragment(s, type, buf, len, peek)))
 774                 return ret;
 775
 776         /* Now s->d1->handshake_fragment_len == 0 if type == SSL3_RT_HANDSHAKE. */
 777
 778 #ifndef OPENSSL_NO_SCTP
 779         /* Continue handshake if it had to be interrupted to read
 780          * app data with SCTP.
 781          */
 782         if ((!s->in_handshake && SSL_in_init(s)) ||
 783             (BIO_dgram_is_sctp(SSL_get_rbio(s)) &&
 784              (s->state == DTLS1_SCTP_ST_SR_READ_SOCK || s->state == DTLS1_SCTP_ST_CR_READ_SOCK) &&
 785              s->s3->in_read_app_data != 2))
 786 #else
 787         if (!s->in_handshake && SSL_in_init(s))
 788 #endif
 789                 {
 790                 /* type == SSL3_RT_APPLICATION_DATA */
 791                 i=s->handshake_func(s);
 792                 if (i < 0) return(i);
 793                 if (i == 0)
 794                         {
 795                         SSLerr(SSL_F_DTLS1_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
 796                         return(-1);
 797                         }
 798                 }
 799
 800 start:
 801         s->rwstate=SSL_NOTHING;
 802
 803         /* s->s3->rrec.type         - is the type of record
 804          * s->s3->rrec.data,    - data
 805          * s->s3->rrec.off,     - offset into 'data' for next read
 806          * s->s3->rrec.length,  - number of bytes. */
 807         rr = &(s->s3->rrec);
 808
 809         /* We are not handshaking and have no data yet,
 810          * so process data buffered during the last handshake
 811          * in advance, if any.
 812          */
 813         if (s->state == SSL_ST_OK && rr->length == 0)
 814                 {
 815                 pitem *item;
 816                 item = pqueue_pop(s->d1->buffered_app_data.q);
 817                 if (item)
 818                         {
 819 #ifndef OPENSSL_NO_SCTP
 820                         /* Restore bio_dgram_sctp_rcvinfo struct */
 821                         if (BIO_dgram_is_sctp(SSL_get_rbio(s)))
 822                                 {
 823                                 DTLS1_RECORD_DATA *rdata = (DTLS1_RECORD_DATA *) item->data;
 824                                 BIO_ctrl(SSL_get_rbio(s), BIO_CTRL_DGRAM_SCTP_SET_RCVINFO, sizeof(rdata->recordinfo), &rdata->recordinfo);
 825                                 }
 826 #endif
 827
 828                         dtls1_copy_record(s, item);
 829
 830                         OPENSSL_free(item->data);
 831                         pitem_free(item);
 832                         }
 833                 }
 834
 835         /* Check for timeout */
 836         if (dtls1_handle_timeout(s) > 0)
 837                 goto start;
 838
 839         /* get new packet if necessary */
 840         if ((rr->length == 0) || (s->rstate == SSL_ST_READ_BODY))
 841                 {
 842                 ret=dtls1_get_record(s);
 843                 if (ret <= 0)
 844                         {
 845                         ret = dtls1_read_failed(s, ret);
 846                         /* anything other than a timeout is an error */
 847                         if (ret <= 0)
 848                                 return(ret);
 849                         else
 850                                 goto start;
 851                         }
 852                 }
 853
 854         if (s->d1->listen && rr->type != SSL3_RT_HANDSHAKE)
 855                 {
 856                 rr->length = 0;
 857                 goto start;
 858                 }
 859
 860         /* we now have a packet which can be read and processed */
 861
 862         if (s->s3->change_cipher_spec /* set when we receive ChangeCipherSpec,
 863                                        * reset by ssl3_get_finished */
 864                 && (rr->type != SSL3_RT_HANDSHAKE))
 865                 {
 866                 /* We now have application data between CCS and Finished.
 867                  * Most likely the packets were reordered on their way, so
 868                  * buffer the application data for later processing rather
 869                  * than dropping the connection.
 870                  */
 871                 dtls1_buffer_record(s, &(s->d1->buffered_app_data), rr->seq_num);
 872                 rr->length = 0;
 873                 goto start;
 874                 }
 875
 876         /* If the other end has shut down, throw anything we read away
 877          * (even in 'peek' mode) */
 878         if (s->shutdown & SSL_RECEIVED_SHUTDOWN)
 879                 {
 880                 rr->length=0;
 881                 s->rwstate=SSL_NOTHING;
 882                 return(0);
 883                 }
 884
 885
 886         if (type == rr->type) /* SSL3_RT_APPLICATION_DATA or SSL3_RT_HANDSHAKE */
 887                 {
 888                 /* make sure that we are not getting application data when we
 889                  * are doing a handshake for the first time */
 890                 if (SSL_in_init(s) && (type == SSL3_RT_APPLICATION_DATA) &&
 891                         (s->enc_read_ctx == NULL))
 892                         {
 893                         al=SSL_AD_UNEXPECTED_MESSAGE;
 894                         SSLerr(SSL_F_DTLS1_READ_BYTES,SSL_R_APP_DATA_IN_HANDSHAKE);
 895                         goto f_err;
 896                         }
 897
 898                 if (len <= 0) return(len);
 899
 900                 if ((unsigned int)len > rr->length)
 901                         n = rr->length;
 902                 else
 903                         n = (unsigned int)len;
 904
 905                 memcpy(buf,&(rr->data[rr->off]),n);
 906                 if (!peek)
 907                         {
 908                         rr->length-=n;
 909                         rr->off+=n;
 910                         if (rr->length == 0)
 911                                 {
 912                                 s->rstate=SSL_ST_READ_HEADER;
 913                                 rr->off=0;
 914                                 }
 915                         }
 916
 917 #ifndef OPENSSL_NO_SCTP
 918                         /* We were about to renegotiate but had to read
 919                          * belated application data first, so retry.
 920                          */
 921                         if (BIO_dgram_is_sctp(SSL_get_rbio(s)) &&
 922                             rr->type == SSL3_RT_APPLICATION_DATA &&
 923                             (s->state == DTLS1_SCTP_ST_SR_READ_SOCK || s->state == DTLS1_SCTP_ST_CR_READ_SOCK))
 924                                 {
 925                                 s->rwstate=SSL_READING;
 926                                 BIO_clear_retry_flags(SSL_get_rbio(s));
 927                                 BIO_set_retry_read(SSL_get_rbio(s));
 928                                 }
 929
 930                         /* We might had to delay a close_notify alert because
 931                          * of reordered app data. If there was an alert and there
 932                          * is no message to read anymore, finally set shutdown.
 933                          */
 934                         if (BIO_dgram_is_sctp(SSL_get_rbio(s)) &&
 935                             s->d1->shutdown_received && !BIO_dgram_sctp_msg_waiting(SSL_get_rbio(s)))
 936                                 {
 937                                 s->shutdown |= SSL_RECEIVED_SHUTDOWN;
 938                                 return(0);
 939                                 }
 940 #endif
 941                 return(n);
 942                 }
 943
 944
 945         /* If we get here, then type != rr->type; if we have a handshake
 946          * message, then it was unexpected (Hello Request or Client Hello). */
 947
 948         /* In case of record types for which we have 'fragment' storage,
 949          * fill that so that we can process the data at a fixed place.
 950          */
 951                 {
 952                 unsigned int k, dest_maxlen = 0;
 953                 unsigned char *dest = NULL;
 954                 unsigned int *dest_len = NULL;
 955
 956                 if (rr->type == SSL3_RT_HANDSHAKE)
 957                         {
 958                         dest_maxlen = sizeof s->d1->handshake_fragment;
 959                         dest = s->d1->handshake_fragment;
 960                         dest_len = &s->d1->handshake_fragment_len;
 961                         }
 962                 else if (rr->type == SSL3_RT_ALERT)
 963                         {
 964                         dest_maxlen = sizeof(s->d1->alert_fragment);
 965                         dest = s->d1->alert_fragment;
 966                         dest_len = &s->d1->alert_fragment_len;
 967                         }
 968 #ifndef OPENSSL_NO_HEARTBEATS
 969                 else if (rr->type == TLS1_RT_HEARTBEAT)
 970                         {
 971                         dtls1_process_heartbeat(s);
 972
 973                         /* Exit and notify application to read again */
 974                         rr->length = 0;
 975                         s->rwstate=SSL_READING;
 976                         BIO_clear_retry_flags(SSL_get_rbio(s));
 977                         BIO_set_retry_read(SSL_get_rbio(s));
 978                         return(-1);
 979                         }
 980 #endif
 981                 /* else it's a CCS message, or application data or wrong */
 982                 else if (rr->type != SSL3_RT_CHANGE_CIPHER_SPEC)
 983                         {
 984                         /* Application data while renegotiating
 985                          * is allowed. Try again reading.
 986                          */
 987                         if (rr->type == SSL3_RT_APPLICATION_DATA)
 988                                 {
 989                                 BIO *bio;
 990                                 s->s3->in_read_app_data=2;
 991                                 bio=SSL_get_rbio(s);
 992                                 s->rwstate=SSL_READING;
 993                                 BIO_clear_retry_flags(bio);
 994                                 BIO_set_retry_read(bio);
 995                                 return(-1);
 996                                 }
 997
 998                         /* Not certain if this is the right error handling */
 999                         al=SSL_AD_UNEXPECTED_MESSAGE;
1000                         SSLerr(SSL_F_DTLS1_READ_BYTES,SSL_R_UNEXPECTED_RECORD);
1001                         goto f_err;
1002                         }
1003
1004                 if (dest_maxlen > 0)
1005                         {
1006             /* XDTLS:  In a pathalogical case, the Client Hello
1007              *  may be fragmented--don't always expect dest_maxlen bytes */
1008                         if ( rr->length < dest_maxlen)
1009                                 {
1010 #ifdef DTLS1_AD_MISSING_HANDSHAKE_MESSAGE
1011                                 /*
1012                                  * for normal alerts rr->length is 2, while
1013                                  * dest_maxlen is 7 if we were to handle this
1014                                  * non-existing alert...
1015                                  */
1016                                 FIX ME
1017 #endif
1018                                 s->rstate=SSL_ST_READ_HEADER;
1019                                 rr->length = 0;
1020                                 goto start;
1021                                 }
1022
1023                         /* now move 'n' bytes: */
1024                         for ( k = 0; k < dest_maxlen; k++)
1025                                 {
1026                                 dest[k] = rr->data[rr->off++];
1027                                 rr->length--;
1028                                 }
1029                         *dest_len = dest_maxlen;
1030                         }
1031                 }
1032
1033         /* s->d1->handshake_fragment_len == 12  iff  rr->type == SSL3_RT_HANDSHAKE;
1034          * s->d1->alert_fragment_len == 7      iff  rr->type == SSL3_RT_ALERT.
1035          * (Possibly rr is 'empty' now, i.e. rr->length may be 0.) */
1036
1037         /* If we are a client, check for an incoming 'Hello Request': */
1038         if ((!s->server) &&
1039                 (s->d1->handshake_fragment_len >= DTLS1_HM_HEADER_LENGTH) &&
1040                 (s->d1->handshake_fragment[0] == SSL3_MT_HELLO_REQUEST) &&
1041                 (s->session != NULL) && (s->session->cipher != NULL))
1042                 {
1043                 s->d1->handshake_fragment_len = 0;
1044
1045                 if ((s->d1->handshake_fragment[1] != 0) ||
1046                         (s->d1->handshake_fragment[2] != 0) ||
1047                         (s->d1->handshake_fragment[3] != 0))
1048                         {
1049                         al=SSL_AD_DECODE_ERROR;
1050                         SSLerr(SSL_F_DTLS1_READ_BYTES,SSL_R_BAD_HELLO_REQUEST);
1051                         goto err;
1052                         }
1053
1054                 /* no need to check sequence number on HELLO REQUEST messages */
1055
1056                 if (s->msg_callback)
1057                         s->msg_callback(0, s->version, SSL3_RT_HANDSHAKE,
1058                                 s->d1->handshake_fragment, 4, s, s->msg_callback_arg);
1059
1060                 if (SSL_is_init_finished(s) &&
1061                         !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS) &&
1062                         !s->s3->renegotiate)
1063                         {
1064                         s->d1->handshake_read_seq++;
1065                         s->new_session = 1;
1066                         ssl3_renegotiate(s);
1067                         if (ssl3_renegotiate_check(s))
1068                                 {
1069                                 i=s->handshake_func(s);
1070                                 if (i < 0) return(i);
1071                                 if (i == 0)
1072                                         {
1073                                         SSLerr(SSL_F_DTLS1_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
1074                                         return(-1);
1075                                         }
1076
1077                                 if (!(s->mode & SSL_MODE_AUTO_RETRY))
1078                                         {
1079                                         if (s->s3->rbuf.left == 0) /* no read-ahead left? */
1080                                                 {
1081                                                 BIO *bio;
1082                                                 /* In the case where we try to read application data,
1083                                                  * but we trigger an SSL handshake, we return -1 with
1084                                                  * the retry option set.  Otherwise renegotiation may
1085                                                  * cause nasty problems in the blocking world */
1086                                                 s->rwstate=SSL_READING;
1087                                                 bio=SSL_get_rbio(s);
1088                                                 BIO_clear_retry_flags(bio);
1089                                                 BIO_set_retry_read(bio);
1090                                                 return(-1);
1091                                                 }
1092                                         }
1093                                 }
1094                         }
1095                 /* we either finished a handshake or ignored the request,
1096                  * now try again to obtain the (application) data we were asked for */
1097                 goto start;
1098                 }
1099
1100         if (s->d1->alert_fragment_len >= DTLS1_AL_HEADER_LENGTH)
1101                 {
1102                 int alert_level = s->d1->alert_fragment[0];
1103                 int alert_descr = s->d1->alert_fragment[1];
1104
1105                 s->d1->alert_fragment_len = 0;
1106
1107                 if (s->msg_callback)
1108                         s->msg_callback(0, s->version, SSL3_RT_ALERT,
1109                                 s->d1->alert_fragment, 2, s, s->msg_callback_arg);
1110
1111                 if (s->info_callback != NULL)
1112                         cb=s->info_callback;
1113                 else if (s->ctx->info_callback != NULL)
1114                         cb=s->ctx->info_callback;
1115
1116                 if (cb != NULL)
1117                         {
1118                         j = (alert_level << 8) | alert_descr;
1119                         cb(s, SSL_CB_READ_ALERT, j);
1120                         }
1121
1122                 if (alert_level == 1) /* warning */
1123                         {
1124                         s->s3->warn_alert = alert_descr;
1125                         if (alert_descr == SSL_AD_CLOSE_NOTIFY)
1126                                 {
1127 #ifndef OPENSSL_NO_SCTP
1128                                 /* With SCTP and streams the socket may deliver app data
1129                                  * after a close_notify alert. We have to check this
1130                                  * first so that nothing gets discarded.
1131                                  */
1132                                 if (BIO_dgram_is_sctp(SSL_get_rbio(s)) &&
1133                                         BIO_dgram_sctp_msg_waiting(SSL_get_rbio(s)))
1134                                         {
1135                                         s->d1->shutdown_received = 1;
1136                                         s->rwstate=SSL_READING;
1137                                         BIO_clear_retry_flags(SSL_get_rbio(s));
1138                                         BIO_set_retry_read(SSL_get_rbio(s));
1139                                         return -1;
1140                                         }
1141 #endif
1142                                 s->shutdown |= SSL_RECEIVED_SHUTDOWN;
1143                                 return(0);
1144                                 }
1145 #if 0
1146             /* XXX: this is a possible improvement in the future */
1147                         /* now check if it's a missing record */
1148                         if (alert_descr == DTLS1_AD_MISSING_HANDSHAKE_MESSAGE)
1149                                 {
1150                                 unsigned short seq;
1151                                 unsigned int frag_off;
1152                                 unsigned char *p = &(s->d1->alert_fragment[2]);
1153
1154                                 n2s(p, seq);
1155                                 n2l3(p, frag_off);
1156
1157                                 dtls1_retransmit_message(s,
1158                                                                                  dtls1_get_queue_priority(frag->msg_header.seq, 0),
1159                                                                                  frag_off, &found);
1160                                 if ( ! found  && SSL_in_init(s))
1161                                         {
1162                                         /* fprintf( stderr,"in init = %d\n", SSL_in_init(s)); */
1163                                         /* requested a message not yet sent,
1164                                            send an alert ourselves */
1165                                         ssl3_send_alert(s,SSL3_AL_WARNING,
1166                                                 DTLS1_AD_MISSING_HANDSHAKE_MESSAGE);
1167                                         }
1168                                 }
1169 #endif
1170                         }
1171                 else if (alert_level == 2) /* fatal */
1172                         {
1173                         char tmp[16];
1174
1175                         s->rwstate=SSL_NOTHING;
1176                         s->s3->fatal_alert = alert_descr;
1177                         SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_AD_REASON_OFFSET + alert_descr);
1178                         BIO_snprintf(tmp,sizeof tmp,"%d",alert_descr);
1179                         ERR_add_error_data(2,"SSL alert number ",tmp);
1180                         s->shutdown|=SSL_RECEIVED_SHUTDOWN;
1181                         SSL_CTX_remove_session(s->ctx,s->session);
1182                         return(0);
1183                         }
1184                 else
1185                         {
1186                         al=SSL_AD_ILLEGAL_PARAMETER;
1187                         SSLerr(SSL_F_DTLS1_READ_BYTES,SSL_R_UNKNOWN_ALERT_TYPE);
1188                         goto f_err;
1189                         }
1190
1191                 goto start;
1192                 }
1193
1194         if (s->shutdown & SSL_SENT_SHUTDOWN) /* but we have not received a shutdown */
1195                 {
1196                 s->rwstate=SSL_NOTHING;
1197                 rr->length=0;
1198                 return(0);
1199                 }
1200
1201         if (rr->type == SSL3_RT_CHANGE_CIPHER_SPEC)
1202                 {
1203                 struct ccs_header_st ccs_hdr;
1204                 unsigned int ccs_hdr_len = DTLS1_CCS_HEADER_LENGTH;
1205
1206                 dtls1_get_ccs_header(rr->data, &ccs_hdr);
1207
1208                 if (s->version == DTLS1_BAD_VER)
1209                         ccs_hdr_len = 3;
1210
1211                 /* 'Change Cipher Spec' is just a single byte, so we know
1212                  * exactly what the record payload has to look like */
1213                 /* XDTLS: check that epoch is consistent */
1214                 if (    (rr->length != ccs_hdr_len) ||
1215                         (rr->off != 0) || (rr->data[0] != SSL3_MT_CCS))
1216                         {
1217                         i=SSL_AD_ILLEGAL_PARAMETER;
1218                         SSLerr(SSL_F_DTLS1_READ_BYTES,SSL_R_BAD_CHANGE_CIPHER_SPEC);
1219                         goto err;
1220                         }
1221
1222                 rr->length=0;
1223
1224                 if (s->msg_callback)
1225                         s->msg_callback(0, s->version, SSL3_RT_CHANGE_CIPHER_SPEC,
1226                                 rr->data, 1, s, s->msg_callback_arg);
1227
1228                 /* We can't process a CCS now, because previous handshake
1229                  * messages are still missing, so just drop it.
1230                  */
1231                 if (!s->d1->change_cipher_spec_ok)
1232                         {
1233                         goto start;
1234                         }
1235
1236                 s->d1->change_cipher_spec_ok = 0;
1237
1238                 s->s3->change_cipher_spec=1;
1239                 if (!ssl3_do_change_cipher_spec(s))
1240                         goto err;
1241
1242                 /* do this whenever CCS is processed */
1243                 dtls1_reset_seq_numbers(s, SSL3_CC_READ);
1244
1245                 if (s->version == DTLS1_BAD_VER)
1246                         s->d1->handshake_read_seq++;
1247
1248 #ifndef OPENSSL_NO_SCTP
1249                 /* Remember that a CCS has been received,
1250                  * so that an old key of SCTP-Auth can be
1251                  * deleted when a CCS is sent. Will be ignored
1252                  * if no SCTP is used
1253                  */
1254                 BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_AUTH_CCS_RCVD, 1, NULL);
1255 #endif
1256
1257                 goto start;
1258                 }
1259
1260         /* Unexpected handshake message (Client Hello, or protocol violation) */
1261         if ((s->d1->handshake_fragment_len >= DTLS1_HM_HEADER_LENGTH) &&
1262                 !s->in_handshake)
1263                 {
1264                 struct hm_header_st msg_hdr;
1265
1266                 /* this may just be a stale retransmit */
1267                 dtls1_get_message_header(rr->data, &msg_hdr);
1268                 if( rr->epoch != s->d1->r_epoch)
1269                         {
1270                         rr->length = 0;
1271                         goto start;
1272                         }
1273
1274                 /* If we are server, we may have a repeated FINISHED of the
1275                  * client here, then retransmit our CCS and FINISHED.
1276                  */
1277                 if (msg_hdr.type == SSL3_MT_FINISHED)
1278                         {
1279                         if (dtls1_check_timeout_num(s) < 0)
1280                                 return -1;
1281
1282                         dtls1_retransmit_buffered_messages(s);
1283                         rr->length = 0;
1284                         goto start;
1285                         }
1286
1287                 if (((s->state&SSL_ST_MASK) == SSL_ST_OK) &&
1288                         !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS))
1289                         {
1290 #if 0 /* worked only because C operator preferences are not as expected (and
1291        * because this is not really needed for clients except for detecting
1292        * protocol violations): */
1293                         s->state=SSL_ST_BEFORE|(s->server)
1294                                 ?SSL_ST_ACCEPT
1295                                 :SSL_ST_CONNECT;
1296 #else
1297                         s->state = s->server ? SSL_ST_ACCEPT : SSL_ST_CONNECT;
1298 #endif
1299                         s->renegotiate=1;
1300                         s->new_session=1;
1301                         }
1302                 i=s->handshake_func(s);
1303                 if (i < 0) return(i);
1304                 if (i == 0)
1305                         {
1306                         SSLerr(SSL_F_DTLS1_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
1307                         return(-1);
1308                         }
1309
1310                 if (!(s->mode & SSL_MODE_AUTO_RETRY))
1311                         {
1312                         if (s->s3->rbuf.left == 0) /* no read-ahead left? */
1313                                 {
1314                                 BIO *bio;
1315                                 /* In the case where we try to read application data,
1316                                  * but we trigger an SSL handshake, we return -1 with
1317                                  * the retry option set.  Otherwise renegotiation may
1318                                  * cause nasty problems in the blocking world */
1319                                 s->rwstate=SSL_READING;
1320                                 bio=SSL_get_rbio(s);
1321                                 BIO_clear_retry_flags(bio);
1322                                 BIO_set_retry_read(bio);
1323                                 return(-1);
1324                                 }
1325                         }
1326                 goto start;
1327                 }
1328
1329         switch (rr->type)
1330                 {
1331         default:
1332 #ifndef OPENSSL_NO_TLS
1333                 /* TLS just ignores unknown message types */
1334                 if (s->version == TLS1_VERSION)
1335                         {
1336                         rr->length = 0;
1337                         goto start;
1338                         }
1339 #endif
1340                 al=SSL_AD_UNEXPECTED_MESSAGE;
1341                 SSLerr(SSL_F_DTLS1_READ_BYTES,SSL_R_UNEXPECTED_RECORD);
1342                 goto f_err;
1343         case SSL3_RT_CHANGE_CIPHER_SPEC:
1344         case SSL3_RT_ALERT:
1345         case SSL3_RT_HANDSHAKE:
1346                 /* we already handled all of these, with the possible exception
1347                  * of SSL3_RT_HANDSHAKE when s->in_handshake is set, but that
1348                  * should not happen when type != rr->type */
1349                 al=SSL_AD_UNEXPECTED_MESSAGE;
1350                 SSLerr(SSL_F_DTLS1_READ_BYTES,ERR_R_INTERNAL_ERROR);
1351                 goto f_err;
1352         case SSL3_RT_APPLICATION_DATA:
1353                 /* At this point, we were expecting handshake data,
1354                  * but have application data.  If the library was
1355                  * running inside ssl3_read() (i.e. in_read_app_data
1356                  * is set) and it makes sense to read application data
1357                  * at this point (session renegotiation not yet started),
1358                  * we will indulge it.
1359                  */
1360                 if (s->s3->in_read_app_data &&
1361                         (s->s3->total_renegotiations != 0) &&
1362                         ((
1363                                 (s->state & SSL_ST_CONNECT) &&
1364                                 (s->state >= SSL3_ST_CW_CLNT_HELLO_A) &&
1365                                 (s->state <= SSL3_ST_CR_SRVR_HELLO_A)
1366                                 ) || (
1367                                         (s->state & SSL_ST_ACCEPT) &&
1368                                         (s->state <= SSL3_ST_SW_HELLO_REQ_A) &&
1369                                         (s->state >= SSL3_ST_SR_CLNT_HELLO_A)
1370                                         )
1371                                 ))
1372                         {
1373                         s->s3->in_read_app_data=2;
1374                         return(-1);
1375                         }
1376                 else
1377                         {
1378                         al=SSL_AD_UNEXPECTED_MESSAGE;
1379                         SSLerr(SSL_F_DTLS1_READ_BYTES,SSL_R_UNEXPECTED_RECORD);
1380                         goto f_err;
1381                         }
1382                 }
1383         /* not reached */
1384
1385 f_err:
1386         ssl3_send_alert(s,SSL3_AL_FATAL,al);
1387 err:
1388         return(-1);
1389         }
1390
1391 int
1392 dtls1_write_app_data_bytes(SSL *s, int type, const void *buf_, int len)
1393         {
1394         int i;
1395
1396 #ifndef OPENSSL_NO_SCTP
1397                 /* Check if we have to continue an interrupted handshake
1398                  * for reading belated app data with SCTP.
1399                  */
1400                 if ((SSL_in_init(s) && !s->in_handshake) ||
1401                     (BIO_dgram_is_sctp(SSL_get_wbio(s)) &&
1402                      (s->state == DTLS1_SCTP_ST_SR_READ_SOCK || s->state == DTLS1_SCTP_ST_CR_READ_SOCK)))
1403 #else
1404                 if (SSL_in_init(s) && !s->in_handshake)
1405 #endif
1406                 {
1407                 i=s->handshake_func(s);
1408                 if (i < 0) return(i);
1409                 if (i == 0)
1410                         {
1411                         SSLerr(SSL_F_DTLS1_WRITE_APP_DATA_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
1412                         return -1;
1413                         }
1414                 }
1415
1416         if (len > SSL3_RT_MAX_PLAIN_LENGTH)
1417                 {
1418                         SSLerr(SSL_F_DTLS1_WRITE_APP_DATA_BYTES,SSL_R_DTLS_MESSAGE_TOO_BIG);
1419                         return -1;
1420                 }
1421
1422         i = dtls1_write_bytes(s, type, buf_, len);
1423         return i;
1424         }
1425
1426
1427         /* this only happens when a client hello is received and a handshake
1428          * is started. */
1429 static int
1430 have_handshake_fragment(SSL *s, int type, unsigned char *buf,
1431         int len, int peek)
1432         {
1433
1434         if ((type == SSL3_RT_HANDSHAKE) && (s->d1->handshake_fragment_len > 0))
1435                 /* (partially) satisfy request from storage */
1436                 {
1437                 unsigned char *src = s->d1->handshake_fragment;
1438                 unsigned char *dst = buf;
1439                 unsigned int k,n;
1440
1441                 /* peek == 0 */
1442                 n = 0;
1443                 while ((len > 0) && (s->d1->handshake_fragment_len > 0))
1444                         {
1445                         *dst++ = *src++;
1446                         len--; s->d1->handshake_fragment_len--;
1447                         n++;
1448                         }
1449                 /* move any remaining fragment bytes: */
1450                 for (k = 0; k < s->d1->handshake_fragment_len; k++)
1451                         s->d1->handshake_fragment[k] = *src++;
1452                 return n;
1453                 }
1454
1455         return 0;
1456         }
1457
1458
1459
1460
1461 /* Call this to write data in records of type 'type'
1462  * It will return <= 0 if not all data has been sent or non-blocking IO.
1463  */
1464 int dtls1_write_bytes(SSL *s, int type, const void *buf, int len)
1465         {
1466         int i;
1467
1468         OPENSSL_assert(len <= SSL3_RT_MAX_PLAIN_LENGTH);
1469         s->rwstate=SSL_NOTHING;
1470         i=do_dtls1_write(s, type, buf, len, 0);
1471         return i;
1472         }
1473
1474 int do_dtls1_write(SSL *s, int type, const unsigned char *buf, unsigned int len, int create_empty_fragment)
1475         {
1476         unsigned char *p,*pseq;
1477         int i,mac_size,clear=0;
1478         int prefix_len = 0;
1479         int eivlen;
1480         SSL3_RECORD *wr;
1481         SSL3_BUFFER *wb;
1482         SSL_SESSION *sess;
1483
1484         /* first check if there is a SSL3_BUFFER still being written
1485          * out.  This will happen with non blocking IO */
1486         if (s->s3->wbuf.left != 0)
1487                 {
1488                 OPENSSL_assert(0); /* XDTLS:  want to see if we ever get here */
1489                 return(ssl3_write_pending(s,type,buf,len));
1490                 }
1491
1492         /* If we have an alert to send, lets send it */
1493         if (s->s3->alert_dispatch)
1494                 {
1495                 i=s->method->ssl_dispatch_alert(s);
1496                 if (i <= 0)
1497                         return(i);
1498                 /* if it went, fall through and send more stuff */
1499                 }
1500
1501         if (len == 0 && !create_empty_fragment)
1502                 return 0;
1503
1504         wr= &(s->s3->wrec);
1505         wb= &(s->s3->wbuf);
1506         sess=s->session;
1507
1508         if (    (sess == NULL) ||
1509                 (s->enc_write_ctx == NULL) ||
1510                 (EVP_MD_CTX_md(s->write_hash) == NULL))
1511                 clear=1;
1512
1513         if (clear)
1514                 mac_size=0;
1515         else
1516                 {
1517                 mac_size=EVP_MD_CTX_size(s->write_hash);
1518                 if (mac_size < 0)
1519                         goto err;
1520                 }
1521
1522         /* DTLS implements explicit IV, so no need for empty fragments */
1523 #if 0
1524         /* 'create_empty_fragment' is true only when this function calls itself */
1525         if (!clear && !create_empty_fragment && !s->s3->empty_fragment_done
1526             && SSL_version(s) != DTLS1_VERSION && SSL_version(s) != DTLS1_BAD_VER)
1527                 {
1528                 /* countermeasure against known-IV weakness in CBC ciphersuites
1529                  * (see http://www.openssl.org/~bodo/tls-cbc.txt)
1530                  */
1531
1532                 if (s->s3->need_empty_fragments && type == SSL3_RT_APPLICATION_DATA)
1533                         {
1534                         /* recursive function call with 'create_empty_fragment' set;
1535                          * this prepares and buffers the data for an empty fragment
1536                          * (these 'prefix_len' bytes are sent out later
1537                          * together with the actual payload) */
1538                         prefix_len = s->method->do_ssl_write(s, type, buf, 0, 1);
1539                         if (prefix_len <= 0)
1540                                 goto err;
1541
1542                         if (s->s3->wbuf.len < (size_t)prefix_len + SSL3_RT_MAX_PACKET_SIZE)
1543                                 {
1544                                 /* insufficient space */
1545                                 SSLerr(SSL_F_DO_DTLS1_WRITE, ERR_R_INTERNAL_ERROR);
1546                                 goto err;
1547                                 }
1548                         }
1549
1550                 s->s3->empty_fragment_done = 1;
1551                 }
1552 #endif
1553         p = wb->buf + prefix_len;
1554
1555         /* write the header */
1556
1557         *(p++)=type&0xff;
1558         wr->type=type;
1559         /* Special case: for hello verify request, client version 1.0 and
1560          * we haven't decided which version to use yet send back using
1561          * version 1.0 header: otherwise some clients will ignore it.
1562          */
1563         if (s->method->version == DTLS_ANY_VERSION)
1564                 {
1565                 *(p++)=DTLS1_VERSION>>8;
1566                 *(p++)=DTLS1_VERSION&0xff;
1567                 }
1568         else
1569                 {
1570                 *(p++)=s->version>>8;
1571                 *(p++)=s->version&0xff;
1572                 }
1573
1574         /* field where we are to write out packet epoch, seq num and len */
1575         pseq=p;
1576         p+=10;
1577
1578         /* Explicit IV length, block ciphers appropriate version flag */
1579         if (s->enc_write_ctx)
1580                 {
1581                 int mode = EVP_CIPHER_CTX_mode(s->enc_write_ctx);
1582                 if (mode == EVP_CIPH_CBC_MODE)
1583                         {
1584                         eivlen = EVP_CIPHER_CTX_iv_length(s->enc_write_ctx);
1585                         if (eivlen <= 1)
1586                                 eivlen = 0;
1587                         }
1588                 /* Need explicit part of IV for GCM mode */
1589                 else if (mode == EVP_CIPH_GCM_MODE)
1590                         eivlen = EVP_GCM_TLS_EXPLICIT_IV_LEN;
1591                 else
1592                         eivlen = 0;
1593                 }
1594         else
1595                 eivlen = 0;
1596
1597         /* lets setup the record stuff. */
1598         wr->data=p + eivlen;  /* make room for IV in case of CBC */
1599         wr->length=(int)len;
1600         wr->input=(unsigned char *)buf;
1601
1602         /* we now 'read' from wr->input, wr->length bytes into
1603          * wr->data */
1604
1605         /* first we compress */
1606         if (s->compress != NULL)
1607                 {
1608                 if (!ssl3_do_compress(s))
1609                         {
1610                         SSLerr(SSL_F_DO_DTLS1_WRITE,SSL_R_COMPRESSION_FAILURE);
1611                         goto err;
1612                         }
1613                 }
1614         else
1615                 {
1616                 memcpy(wr->data,wr->input,wr->length);
1617                 wr->input=wr->data;
1618                 }
1619
1620         /* we should still have the output to wr->data and the input
1621          * from wr->input.  Length should be wr->length.
1622          * wr->data still points in the wb->buf */
1623
1624         if (mac_size != 0)
1625                 {
1626                 if(s->method->ssl3_enc->mac(s,&(p[wr->length + eivlen]),1) < 0)
1627                         goto err;
1628                 wr->length+=mac_size;
1629                 }
1630
1631         /* this is true regardless of mac size */
1632         wr->input=p;
1633         wr->data=p;
1634
1635         if (eivlen)
1636                 wr->length += eivlen;
1637
1638         s->method->ssl3_enc->enc(s,1);
1639
1640         /* record length after mac and block padding */
1641 /*      if (type == SSL3_RT_APPLICATION_DATA ||
1642         (type == SSL3_RT_ALERT && ! SSL_in_init(s))) */
1643
1644         /* there's only one epoch between handshake and app data */
1645
1646         s2n(s->d1->w_epoch, pseq);
1647
1648         /* XDTLS: ?? */
1649 /*      else
1650         s2n(s->d1->handshake_epoch, pseq); */
1651
1652         memcpy(pseq, &(s->s3->write_sequence[2]), 6);
1653         pseq+=6;
1654         s2n(wr->length,pseq);
1655
1656         if (s->msg_callback)
1657                 s->msg_callback(1, 0, SSL3_RT_HEADER, pseq - DTLS1_RT_HEADER_LENGTH, DTLS1_RT_HEADER_LENGTH, s, s->msg_callback_arg);
1658
1659         /* we should now have
1660          * wr->data pointing to the encrypted data, which is
1661          * wr->length long */
1662         wr->type=type; /* not needed but helps for debugging */
1663         wr->length+=DTLS1_RT_HEADER_LENGTH;
1664
1665 #if 0  /* this is now done at the message layer */
1666         /* buffer the record, making it easy to handle retransmits */
1667         if ( type == SSL3_RT_HANDSHAKE || type == SSL3_RT_CHANGE_CIPHER_SPEC)
1668                 dtls1_buffer_record(s, wr->data, wr->length,
1669                         *((PQ_64BIT *)&(s->s3->write_sequence[0])));
1670 #endif
1671
1672         ssl3_record_sequence_update(&(s->s3->write_sequence[0]));
1673
1674         if (create_empty_fragment)
1675                 {
1676                 /* we are in a recursive call;
1677                  * just return the length, don't write out anything here
1678                  */
1679                 return wr->length;
1680                 }
1681
1682         /* now let's set up wb */
1683         wb->left = prefix_len + wr->length;
1684         wb->offset = 0;
1685
1686         /* memorize arguments so that ssl3_write_pending can detect bad write retries later */
1687         s->s3->wpend_tot=len;
1688         s->s3->wpend_buf=buf;
1689         s->s3->wpend_type=type;
1690         s->s3->wpend_ret=len;
1691
1692         /* we now just need to write the buffer */
1693         return ssl3_write_pending(s,type,buf,len);
1694 err:
1695         return -1;
1696         }
1697
1698
1699
1700 static int dtls1_record_replay_check(SSL *s, DTLS1_BITMAP *bitmap)
1701         {
1702         int cmp;
1703         unsigned int shift;
1704         const unsigned char *seq = s->s3->read_sequence;
1705
1706         cmp = satsub64be(seq,bitmap->max_seq_num);
1707         if (cmp > 0)
1708                 {
1709                 memcpy (s->s3->rrec.seq_num,seq,8);
1710                 return 1; /* this record in new */
1711                 }
1712         shift = -cmp;
1713         if (shift >= sizeof(bitmap->map)*8)
1714                 return 0; /* stale, outside the window */
1715         else if (bitmap->map & (1UL<<shift))
1716                 return 0; /* record previously received */
1717
1718         memcpy (s->s3->rrec.seq_num,seq,8);
1719         return 1;
1720         }
1721
1722
1723 static void dtls1_record_bitmap_update(SSL *s, DTLS1_BITMAP *bitmap)
1724         {
1725         int cmp;
1726         unsigned int shift;
1727         const unsigned char *seq = s->s3->read_sequence;
1728
1729         cmp = satsub64be(seq,bitmap->max_seq_num);
1730         if (cmp > 0)
1731                 {
1732                 shift = cmp;
1733                 if (shift < sizeof(bitmap->map)*8)
1734                         bitmap->map <<= shift, bitmap->map |= 1UL;
1735                 else
1736                         bitmap->map = 1UL;
1737                 memcpy(bitmap->max_seq_num,seq,8);
1738                 }
1739         else    {
1740                 shift = -cmp;
1741                 if (shift < sizeof(bitmap->map)*8)
1742                         bitmap->map |= 1UL<<shift;
1743                 }
1744         }
1745
1746
1747 int dtls1_dispatch_alert(SSL *s)
1748         {
1749         int i,j;
1750         void (*cb)(const SSL *ssl,int type,int val)=NULL;
1751         unsigned char buf[DTLS1_AL_HEADER_LENGTH];
1752         unsigned char *ptr = &buf[0];
1753
1754         s->s3->alert_dispatch=0;
1755
1756         memset(buf, 0x00, sizeof(buf));
1757         *ptr++ = s->s3->send_alert[0];
1758         *ptr++ = s->s3->send_alert[1];
1759
1760 #ifdef DTLS1_AD_MISSING_HANDSHAKE_MESSAGE
1761         if (s->s3->send_alert[1] == DTLS1_AD_MISSING_HANDSHAKE_MESSAGE)
1762                 {
1763                 s2n(s->d1->handshake_read_seq, ptr);
1764 #if 0
1765                 if ( s->d1->r_msg_hdr.frag_off == 0)  /* waiting for a new msg */
1766
1767                 else
1768                         s2n(s->d1->r_msg_hdr.seq, ptr); /* partial msg read */
1769 #endif
1770
1771 #if 0
1772                 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);
1773 #endif
1774                 l2n3(s->d1->r_msg_hdr.frag_off, ptr);
1775                 }
1776 #endif
1777
1778         i = do_dtls1_write(s, SSL3_RT_ALERT, &buf[0], sizeof(buf), 0);
1779         if (i <= 0)
1780                 {
1781                 s->s3->alert_dispatch=1;
1782                 /* fprintf( stderr, "not done with alert\n" ); */
1783                 }
1784         else
1785                 {
1786                 if (s->s3->send_alert[0] == SSL3_AL_FATAL
1787 #ifdef DTLS1_AD_MISSING_HANDSHAKE_MESSAGE
1788                     || s->s3->send_alert[1] == DTLS1_AD_MISSING_HANDSHAKE_MESSAGE
1789 #endif
1790                     )
1791                         (void)BIO_flush(s->wbio);
1792
1793                 if (s->msg_callback)
1794                         s->msg_callback(1, s->version, SSL3_RT_ALERT, s->s3->send_alert,
1795                                 2, s, s->msg_callback_arg);
1796
1797                 if (s->info_callback != NULL)
1798                         cb=s->info_callback;
1799                 else if (s->ctx->info_callback != NULL)
1800                         cb=s->ctx->info_callback;
1801
1802                 if (cb != NULL)
1803                         {
1804                         j=(s->s3->send_alert[0]<<8)|s->s3->send_alert[1];
1805                         cb(s,SSL_CB_WRITE_ALERT,j);
1806                         }
1807                 }
1808         return(i);
1809         }
1810
1811
1812 static DTLS1_BITMAP *
1813 dtls1_get_bitmap(SSL *s, SSL3_RECORD *rr, unsigned int *is_next_epoch)
1814     {
1815
1816     *is_next_epoch = 0;
1817
1818     /* In current epoch, accept HM, CCS, DATA, & ALERT */
1819     if (rr->epoch == s->d1->r_epoch)
1820         return &s->d1->bitmap;
1821
1822     /* Only HM and ALERT messages can be from the next epoch */
1823     else if (rr->epoch == (unsigned long)(s->d1->r_epoch + 1) &&
1824         (rr->type == SSL3_RT_HANDSHAKE ||
1825             rr->type == SSL3_RT_ALERT))
1826         {
1827         *is_next_epoch = 1;
1828         return &s->d1->next_bitmap;
1829         }
1830
1831     return NULL;
1832     }
1833
1834 #if 0
1835 static int
1836 dtls1_record_needs_buffering(SSL *s, SSL3_RECORD *rr, unsigned short *priority,
1837         unsigned long *offset)
1838         {
1839
1840         /* alerts are passed up immediately */
1841         if ( rr->type == SSL3_RT_APPLICATION_DATA ||
1842                 rr->type == SSL3_RT_ALERT)
1843                 return 0;
1844
1845         /* Only need to buffer if a handshake is underway.
1846          * (this implies that Hello Request and Client Hello are passed up
1847          * immediately) */
1848         if ( SSL_in_init(s))
1849                 {
1850                 unsigned char *data = rr->data;
1851                 /* need to extract the HM/CCS sequence number here */
1852                 if ( rr->type == SSL3_RT_HANDSHAKE ||
1853                         rr->type == SSL3_RT_CHANGE_CIPHER_SPEC)
1854                         {
1855                         unsigned short seq_num;
1856                         struct hm_header_st msg_hdr;
1857                         struct ccs_header_st ccs_hdr;
1858
1859                         if ( rr->type == SSL3_RT_HANDSHAKE)
1860                                 {
1861                                 dtls1_get_message_header(data, &msg_hdr);
1862                                 seq_num = msg_hdr.seq;
1863                                 *offset = msg_hdr.frag_off;
1864                                 }
1865                         else
1866                                 {
1867                                 dtls1_get_ccs_header(data, &ccs_hdr);
1868                                 seq_num = ccs_hdr.seq;
1869                                 *offset = 0;
1870                                 }
1871
1872                         /* this is either a record we're waiting for, or a
1873                          * retransmit of something we happened to previously
1874                          * receive (higher layers will drop the repeat silently */
1875                         if ( seq_num < s->d1->handshake_read_seq)
1876                                 return 0;
1877                         if (rr->type == SSL3_RT_HANDSHAKE &&
1878                                 seq_num == s->d1->handshake_read_seq &&
1879                                 msg_hdr.frag_off < s->d1->r_msg_hdr.frag_off)
1880                                 return 0;
1881                         else if ( seq_num == s->d1->handshake_read_seq &&
1882                                 (rr->type == SSL3_RT_CHANGE_CIPHER_SPEC ||
1883                                         msg_hdr.frag_off == s->d1->r_msg_hdr.frag_off))
1884                                 return 0;
1885                         else
1886                                 {
1887                                 *priority = seq_num;
1888                                 return 1;
1889                                 }
1890                         }
1891                 else /* unknown record type */
1892                         return 0;
1893                 }
1894
1895         return 0;
1896         }
1897 #endif
1898
1899 void
1900 dtls1_reset_seq_numbers(SSL *s, int rw)
1901         {
1902         unsigned char *seq;
1903         unsigned int seq_bytes = sizeof(s->s3->read_sequence);
1904
1905         if ( rw & SSL3_CC_READ)
1906                 {
1907                 seq = s->s3->read_sequence;
1908                 s->d1->r_epoch++;
1909                 memcpy(&(s->d1->bitmap), &(s->d1->next_bitmap), sizeof(DTLS1_BITMAP));
1910                 memset(&(s->d1->next_bitmap), 0x00, sizeof(DTLS1_BITMAP));
1911                 }
1912         else
1913                 {
1914                 seq = s->s3->write_sequence;
1915                 memcpy(s->d1->last_write_sequence, seq, sizeof(s->s3->write_sequence));
1916                 s->d1->w_epoch++;
1917                 }
1918
1919         memset(seq, 0x00, seq_bytes);
1920         }