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 we're not (re)negotiating, nothing buffered */
 347         if ( ! SSL_in_init(s))
 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         /*-
 422          * enc_err is:
 423          *    0: (in non-constant time) if the record is publically invalid.
 424          *    1: if the padding is valid
 425          *   -1: if the padding is invalid
 426          */
 427         if (enc_err == 0)
 428                 {
 429                 /* For DTLS we simply ignore bad packets. */
 430                 rr->length = 0;
 431                 s->packet_length = 0;
 432                 goto err;
 433                 }
 434
 435 #ifdef TLS_DEBUG
 436 printf("dec %d\n",rr->length);
 437 { unsigned int z; for (z=0; z<rr->length; z++) printf("%02X%c",rr->data[z],((z+1)%16)?' ':'\n'); }
 438 printf("\n");
 439 #endif
 440
 441         /* r->length is now the compressed data plus mac */
 442         if ((sess != NULL) &&
 443             (s->enc_read_ctx != NULL) &&
 444             (EVP_MD_CTX_md(s->read_hash) != NULL))
 445                 {
 446                 /* s->read_hash != NULL => mac_size != -1 */
 447                 unsigned char *mac = NULL;
 448                 unsigned char mac_tmp[EVP_MAX_MD_SIZE];
 449                 mac_size=EVP_MD_CTX_size(s->read_hash);
 450                 OPENSSL_assert(mac_size <= EVP_MAX_MD_SIZE);
 451
 452                 /* kludge: *_cbc_remove_padding passes padding length in rr->type */
 453                 orig_len = rr->length+((unsigned int)rr->type>>8);
 454
 455                 /* orig_len is the length of the record before any padding was
 456                  * removed. This is public information, as is the MAC in use,
 457                  * therefore we can safely process the record in a different
 458                  * amount of time if it's too short to possibly contain a MAC.
 459                  */
 460                 if (orig_len < mac_size ||
 461                     /* CBC records must have a padding length byte too. */
 462                     (EVP_CIPHER_CTX_mode(s->enc_read_ctx) == EVP_CIPH_CBC_MODE &&
 463                      orig_len < mac_size+1))
 464                         {
 465                         al=SSL_AD_DECODE_ERROR;
 466                         SSLerr(SSL_F_DTLS1_PROCESS_RECORD,SSL_R_LENGTH_TOO_SHORT);
 467                         goto f_err;
 468                         }
 469
 470                 if (EVP_CIPHER_CTX_mode(s->enc_read_ctx) == EVP_CIPH_CBC_MODE)
 471                         {
 472                         /* We update the length so that the TLS header bytes
 473                          * can be constructed correctly but we need to extract
 474                          * the MAC in constant time from within the record,
 475                          * without leaking the contents of the padding bytes.
 476                          * */
 477                         mac = mac_tmp;
 478                         ssl3_cbc_copy_mac(mac_tmp, rr, mac_size, orig_len);
 479                         rr->length -= mac_size;
 480                         }
 481                 else
 482                         {
 483                         /* In this case there's no padding, so |orig_len|
 484                          * equals |rec->length| and we checked that there's
 485                          * enough bytes for |mac_size| above. */
 486                         rr->length -= mac_size;
 487                         mac = &rr->data[rr->length];
 488                         }
 489
 490                 i=s->method->ssl3_enc->mac(s,md,0 /* not send */);
 491                 if (i < 0 || mac == NULL || CRYPTO_memcmp(md, mac, (size_t)mac_size) != 0)
 492                         enc_err = -1;
 493                 if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH+mac_size)
 494                         enc_err = -1;
 495                 }
 496
 497         if (enc_err < 0)
 498                 {
 499                 /* decryption failed, silently discard message */
 500                 rr->length = 0;
 501                 s->packet_length = 0;
 502                 goto err;
 503                 }
 504
 505         /* r->length is now just compressed */
 506         if (s->expand != NULL)
 507                 {
 508                 if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH)
 509                         {
 510                         al=SSL_AD_RECORD_OVERFLOW;
 511                         SSLerr(SSL_F_DTLS1_PROCESS_RECORD,SSL_R_COMPRESSED_LENGTH_TOO_LONG);
 512                         goto f_err;
 513                         }
 514                 if (!ssl3_do_uncompress(s))
 515                         {
 516                         al=SSL_AD_DECOMPRESSION_FAILURE;
 517                         SSLerr(SSL_F_DTLS1_PROCESS_RECORD,SSL_R_BAD_DECOMPRESSION);
 518                         goto f_err;
 519                         }
 520                 }
 521
 522         if (rr->length > SSL3_RT_MAX_PLAIN_LENGTH)
 523                 {
 524                 al=SSL_AD_RECORD_OVERFLOW;
 525                 SSLerr(SSL_F_DTLS1_PROCESS_RECORD,SSL_R_DATA_LENGTH_TOO_LONG);
 526                 goto f_err;
 527                 }
 528
 529         rr->off=0;
 530         /*-
 531          * So at this point the following is true
 532          * ssl->s3->rrec.type   is the type of record
 533          * ssl->s3->rrec.length == number of bytes in record
 534          * ssl->s3->rrec.off    == offset to first valid byte
 535          * ssl->s3->rrec.data   == where to take bytes from, increment
 536          *                         after use :-).
 537          */
 538
 539         /* we have pulled in a full packet so zero things */
 540         s->packet_length=0;
 541         return(1);
 542
 543 f_err:
 544         ssl3_send_alert(s,SSL3_AL_FATAL,al);
 545 err:
 546         return(0);
 547 }
 548
 549
 550 /*-
 551  * Call this to get a new input record.
 552  * It will return <= 0 if more data is needed, normally due to an error
 553  * or non-blocking IO.
 554  * When it finishes, one packet has been decoded and can be found in
 555  * ssl->s3->rrec.type    - is the type of record
 556  * ssl->s3->rrec.data,   - data
 557  * ssl->s3->rrec.length, - number of bytes
 558  */
 559 /* used only by dtls1_read_bytes */
 560 int dtls1_get_record(SSL *s)
 561         {
 562         int ssl_major,ssl_minor;
 563         int i,n;
 564         SSL3_RECORD *rr;
 565         unsigned char *p = NULL;
 566         unsigned short version;
 567         DTLS1_BITMAP *bitmap;
 568         unsigned int is_next_epoch;
 569
 570         rr= &(s->s3->rrec);
 571
 572         /* The epoch may have changed.  If so, process all the
 573          * pending records.  This is a non-blocking operation. */
 574         if(dtls1_process_buffered_records(s)<0)
 575                 return -1;
 576
 577         /* if we're renegotiating, then there may be buffered records */
 578         if (dtls1_get_processed_record(s))
 579                 return 1;
 580
 581         /* get something from the wire */
 582 again:
 583         /* check if we have the header */
 584         if (    (s->rstate != SSL_ST_READ_BODY) ||
 585                 (s->packet_length < DTLS1_RT_HEADER_LENGTH))
 586                 {
 587                 n=ssl3_read_n(s, DTLS1_RT_HEADER_LENGTH, s->s3->rbuf.len, 0);
 588                 /* read timeout is handled by dtls1_read_bytes */
 589                 if (n <= 0) return(n); /* error or non-blocking */
 590
 591                 /* this packet contained a partial record, dump it */
 592                 if (s->packet_length != DTLS1_RT_HEADER_LENGTH)
 593                         {
 594                         s->packet_length = 0;
 595                         goto again;
 596                         }
 597
 598                 s->rstate=SSL_ST_READ_BODY;
 599
 600                 p=s->packet;
 601
 602                 if (s->msg_callback)
 603                         s->msg_callback(0, 0, SSL3_RT_HEADER, p, DTLS1_RT_HEADER_LENGTH, s, s->msg_callback_arg);
 604
 605                 /* Pull apart the header into the DTLS1_RECORD */
 606                 rr->type= *(p++);
 607                 ssl_major= *(p++);
 608                 ssl_minor= *(p++);
 609                 version=(ssl_major<<8)|ssl_minor;
 610
 611                 /* sequence number is 64 bits, with top 2 bytes = epoch */
 612                 n2s(p,rr->epoch);
 613
 614                 memcpy(&(s->s3->read_sequence[2]), p, 6);
 615                 p+=6;
 616
 617                 n2s(p,rr->length);
 618
 619                 /* Lets check version */
 620                 if (!s->first_packet)
 621                         {
 622                         if (version != s->version)
 623                                 {
 624                                 /* unexpected version, silently discard */
 625                                 rr->length = 0;
 626                                 s->packet_length = 0;
 627                                 goto again;
 628                                 }
 629                         }
 630
 631                 if ((version & 0xff00) != (s->version & 0xff00))
 632                         {
 633                         /* wrong version, silently discard record */
 634                         rr->length = 0;
 635                         s->packet_length = 0;
 636                         goto again;
 637                         }
 638
 639                 if (rr->length > SSL3_RT_MAX_ENCRYPTED_LENGTH)
 640                         {
 641                         /* record too long, silently discard it */
 642                         rr->length = 0;
 643                         s->packet_length = 0;
 644                         goto again;
 645                         }
 646
 647                 /* now s->rstate == SSL_ST_READ_BODY */
 648                 }
 649
 650         /* s->rstate == SSL_ST_READ_BODY, get and decode the data */
 651
 652         if (rr->length > s->packet_length-DTLS1_RT_HEADER_LENGTH)
 653                 {
 654                 /* now s->packet_length == DTLS1_RT_HEADER_LENGTH */
 655                 i=rr->length;
 656                 n=ssl3_read_n(s,i,i,1);
 657                 /* this packet contained a partial record, dump it */
 658                 if ( n != i)
 659                         {
 660                         rr->length = 0;
 661                         s->packet_length = 0;
 662                         goto again;
 663                         }
 664
 665                 /* now n == rr->length,
 666                  * and s->packet_length == DTLS1_RT_HEADER_LENGTH + rr->length */
 667                 }
 668         s->rstate=SSL_ST_READ_HEADER; /* set state for later operations */
 669
 670         /* match epochs.  NULL means the packet is dropped on the floor */
 671         bitmap = dtls1_get_bitmap(s, rr, &is_next_epoch);
 672         if ( bitmap == NULL)
 673                 {
 674                 rr->length = 0;
 675                 s->packet_length = 0;  /* dump this record */
 676                 goto again;   /* get another record */
 677                 }
 678
 679 #ifndef OPENSSL_NO_SCTP
 680         /* Only do replay check if no SCTP bio */
 681         if (!BIO_dgram_is_sctp(SSL_get_rbio(s)))
 682                 {
 683 #endif
 684                 /* Check whether this is a repeat, or aged record.
 685                  * Don't check if we're listening and this message is
 686                  * a ClientHello. They can look as if they're replayed,
 687                  * since they arrive from different connections and
 688                  * would be dropped unnecessarily.
 689                  */
 690                 if (!(s->d1->listen && rr->type == SSL3_RT_HANDSHAKE &&
 691                     s->packet_length > DTLS1_RT_HEADER_LENGTH &&
 692                     s->packet[DTLS1_RT_HEADER_LENGTH] == SSL3_MT_CLIENT_HELLO) &&
 693                     !dtls1_record_replay_check(s, bitmap))
 694                         {
 695                         rr->length = 0;
 696                         s->packet_length=0; /* dump this record */
 697                         goto again;     /* get another record */
 698                         }
 699 #ifndef OPENSSL_NO_SCTP
 700                 }
 701 #endif
 702
 703         /* just read a 0 length packet */
 704         if (rr->length == 0) goto again;
 705
 706         /* If this record is from the next epoch (either HM or ALERT),
 707          * and a handshake is currently in progress, buffer it since it
 708          * cannot be processed at this time. However, do not buffer
 709          * anything while listening.
 710          */
 711         if (is_next_epoch)
 712                 {
 713                 if ((SSL_in_init(s) || s->in_handshake) && !s->d1->listen)
 714                         {
 715                         if(dtls1_buffer_record(s, &(s->d1->unprocessed_rcds), rr->seq_num)<0)
 716                                 return -1;
 717                         /* Mark receipt of record. */
 718                         dtls1_record_bitmap_update(s, bitmap);
 719                         }
 720                 rr->length = 0;
 721                 s->packet_length = 0;
 722                 goto again;
 723                 }
 724
 725         if (!dtls1_process_record(s))
 726                 {
 727                 rr->length = 0;
 728                 s->packet_length = 0;  /* dump this record */
 729                 goto again;   /* get another record */
 730                 }
 731         dtls1_record_bitmap_update(s, bitmap);/* Mark receipt of record. */
 732
 733         return(1);
 734
 735         }
 736
 737 /*-
 738  * Return up to 'len' payload bytes received in 'type' records.
 739  * 'type' is one of the following:
 740  *
 741  *   -  SSL3_RT_HANDSHAKE (when ssl3_get_message calls us)
 742  *   -  SSL3_RT_APPLICATION_DATA (when ssl3_read calls us)
 743  *   -  0 (during a shutdown, no data has to be returned)
 744  *
 745  * If we don't have stored data to work from, read a SSL/TLS record first
 746  * (possibly multiple records if we still don't have anything to return).
 747  *
 748  * This function must handle any surprises the peer may have for us, such as
 749  * Alert records (e.g. close_notify), ChangeCipherSpec records (not really
 750  * a surprise, but handled as if it were), or renegotiation requests.
 751  * Also if record payloads contain fragments too small to process, we store
 752  * them until there is enough for the respective protocol (the record protocol
 753  * may use arbitrary fragmentation and even interleaving):
 754  *     Change cipher spec protocol
 755  *             just 1 byte needed, no need for keeping anything stored
 756  *     Alert protocol
 757  *             2 bytes needed (AlertLevel, AlertDescription)
 758  *     Handshake protocol
 759  *             4 bytes needed (HandshakeType, uint24 length) -- we just have
 760  *             to detect unexpected Client Hello and Hello Request messages
 761  *             here, anything else is handled by higher layers
 762  *     Application data protocol
 763  *             none of our business
 764  */
 765 int dtls1_read_bytes(SSL *s, int type, unsigned char *buf, int len, int peek)
 766         {
 767         int al,i,j,ret;
 768         unsigned int n;
 769         SSL3_RECORD *rr;
 770         void (*cb)(const SSL *ssl,int type2,int val)=NULL;
 771
 772         if (s->s3->rbuf.buf == NULL) /* Not initialized yet */
 773                 if (!ssl3_setup_buffers(s))
 774                         return(-1);
 775
 776     /* XXX: check what the second '&& type' is about */
 777         if ((type && (type != SSL3_RT_APPLICATION_DATA) &&
 778                 (type != SSL3_RT_HANDSHAKE) && type) ||
 779             (peek && (type != SSL3_RT_APPLICATION_DATA)))
 780                 {
 781                 SSLerr(SSL_F_DTLS1_READ_BYTES, ERR_R_INTERNAL_ERROR);
 782                 return -1;
 783                 }
 784
 785         /* check whether there's a handshake message (client hello?) waiting */
 786         if ( (ret = have_handshake_fragment(s, type, buf, len, peek)))
 787                 return ret;
 788
 789         /* Now s->d1->handshake_fragment_len == 0 if type == SSL3_RT_HANDSHAKE. */
 790
 791 #ifndef OPENSSL_NO_SCTP
 792         /* Continue handshake if it had to be interrupted to read
 793          * app data with SCTP.
 794          */
 795         if ((!s->in_handshake && SSL_in_init(s)) ||
 796             (BIO_dgram_is_sctp(SSL_get_rbio(s)) &&
 797              (s->state == DTLS1_SCTP_ST_SR_READ_SOCK || s->state == DTLS1_SCTP_ST_CR_READ_SOCK) &&
 798              s->s3->in_read_app_data != 2))
 799 #else
 800         if (!s->in_handshake && SSL_in_init(s))
 801 #endif
 802                 {
 803                 /* type == SSL3_RT_APPLICATION_DATA */
 804                 i=s->handshake_func(s);
 805                 if (i < 0) return(i);
 806                 if (i == 0)
 807                         {
 808                         SSLerr(SSL_F_DTLS1_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
 809                         return(-1);
 810                         }
 811                 }
 812
 813 start:
 814         s->rwstate=SSL_NOTHING;
 815
 816         /*-
 817          * s->s3->rrec.type         - is the type of record
 818          * s->s3->rrec.data,    - data
 819          * s->s3->rrec.off,     - offset into 'data' for next read
 820          * s->s3->rrec.length,  - number of bytes.
 821          */
 822         rr = &(s->s3->rrec);
 823
 824         /* We are not handshaking and have no data yet,
 825          * so process data buffered during the last handshake
 826          * in advance, if any.
 827          */
 828         if (s->state == SSL_ST_OK && rr->length == 0)
 829                 {
 830                 pitem *item;
 831                 item = pqueue_pop(s->d1->buffered_app_data.q);
 832                 if (item)
 833                         {
 834 #ifndef OPENSSL_NO_SCTP
 835                         /* Restore bio_dgram_sctp_rcvinfo struct */
 836                         if (BIO_dgram_is_sctp(SSL_get_rbio(s)))
 837                                 {
 838                                 DTLS1_RECORD_DATA *rdata = (DTLS1_RECORD_DATA *) item->data;
 839                                 BIO_ctrl(SSL_get_rbio(s), BIO_CTRL_DGRAM_SCTP_SET_RCVINFO, sizeof(rdata->recordinfo), &rdata->recordinfo);
 840                                 }
 841 #endif
 842
 843                         dtls1_copy_record(s, item);
 844
 845                         OPENSSL_free(item->data);
 846                         pitem_free(item);
 847                         }
 848                 }
 849
 850         /* Check for timeout */
 851         if (dtls1_handle_timeout(s) > 0)
 852                 goto start;
 853
 854         /* get new packet if necessary */
 855         if ((rr->length == 0) || (s->rstate == SSL_ST_READ_BODY))
 856                 {
 857                 ret=dtls1_get_record(s);
 858                 if (ret <= 0)
 859                         {
 860                         ret = dtls1_read_failed(s, ret);
 861                         /* anything other than a timeout is an error */
 862                         if (ret <= 0)
 863                                 return(ret);
 864                         else
 865                                 goto start;
 866                         }
 867                 }
 868
 869         if (s->d1->listen && rr->type != SSL3_RT_HANDSHAKE)
 870                 {
 871                 rr->length = 0;
 872                 goto start;
 873                 }
 874
 875         /* we now have a packet which can be read and processed */
 876
 877         if (s->s3->change_cipher_spec /* set when we receive ChangeCipherSpec,
 878                                        * reset by ssl3_get_finished */
 879                 && (rr->type != SSL3_RT_HANDSHAKE))
 880                 {
 881                 /* We now have application data between CCS and Finished.
 882                  * Most likely the packets were reordered on their way, so
 883                  * buffer the application data for later processing rather
 884                  * than dropping the connection.
 885                  */
 886                 if(dtls1_buffer_record(s, &(s->d1->buffered_app_data), rr->seq_num)<0)
 887                         {
 888                         SSLerr(SSL_F_DTLS1_READ_BYTES, ERR_R_INTERNAL_ERROR);
 889                         return -1;
 890                         }
 891                 rr->length = 0;
 892                 goto start;
 893                 }
 894
 895         /* If the other end has shut down, throw anything we read away
 896          * (even in 'peek' mode) */
 897         if (s->shutdown & SSL_RECEIVED_SHUTDOWN)
 898                 {
 899                 rr->length=0;
 900                 s->rwstate=SSL_NOTHING;
 901                 return(0);
 902                 }
 903
 904
 905         if (type == rr->type) /* SSL3_RT_APPLICATION_DATA or SSL3_RT_HANDSHAKE */
 906                 {
 907                 /* make sure that we are not getting application data when we
 908                  * are doing a handshake for the first time */
 909                 if (SSL_in_init(s) && (type == SSL3_RT_APPLICATION_DATA) &&
 910                         (s->enc_read_ctx == NULL))
 911                         {
 912                         al=SSL_AD_UNEXPECTED_MESSAGE;
 913                         SSLerr(SSL_F_DTLS1_READ_BYTES,SSL_R_APP_DATA_IN_HANDSHAKE);
 914                         goto f_err;
 915                         }
 916
 917                 if (len <= 0) return(len);
 918
 919                 if ((unsigned int)len > rr->length)
 920                         n = rr->length;
 921                 else
 922                         n = (unsigned int)len;
 923
 924                 memcpy(buf,&(rr->data[rr->off]),n);
 925                 if (!peek)
 926                         {
 927                         rr->length-=n;
 928                         rr->off+=n;
 929                         if (rr->length == 0)
 930                                 {
 931                                 s->rstate=SSL_ST_READ_HEADER;
 932                                 rr->off=0;
 933                                 }
 934                         }
 935
 936 #ifndef OPENSSL_NO_SCTP
 937                         /* We were about to renegotiate but had to read
 938                          * belated application data first, so retry.
 939                          */
 940                         if (BIO_dgram_is_sctp(SSL_get_rbio(s)) &&
 941                             rr->type == SSL3_RT_APPLICATION_DATA &&
 942                             (s->state == DTLS1_SCTP_ST_SR_READ_SOCK || s->state == DTLS1_SCTP_ST_CR_READ_SOCK))
 943                                 {
 944                                 s->rwstate=SSL_READING;
 945                                 BIO_clear_retry_flags(SSL_get_rbio(s));
 946                                 BIO_set_retry_read(SSL_get_rbio(s));
 947                                 }
 948
 949                         /* We might had to delay a close_notify alert because
 950                          * of reordered app data. If there was an alert and there
 951                          * is no message to read anymore, finally set shutdown.
 952                          */
 953                         if (BIO_dgram_is_sctp(SSL_get_rbio(s)) &&
 954                             s->d1->shutdown_received && !BIO_dgram_sctp_msg_waiting(SSL_get_rbio(s)))
 955                                 {
 956                                 s->shutdown |= SSL_RECEIVED_SHUTDOWN;
 957                                 return(0);
 958                                 }
 959 #endif
 960                 return(n);
 961                 }
 962
 963
 964         /* If we get here, then type != rr->type; if we have a handshake
 965          * message, then it was unexpected (Hello Request or Client Hello). */
 966
 967         /* In case of record types for which we have 'fragment' storage,
 968          * fill that so that we can process the data at a fixed place.
 969          */
 970                 {
 971                 unsigned int k, dest_maxlen = 0;
 972                 unsigned char *dest = NULL;
 973                 unsigned int *dest_len = NULL;
 974
 975                 if (rr->type == SSL3_RT_HANDSHAKE)
 976                         {
 977                         dest_maxlen = sizeof s->d1->handshake_fragment;
 978                         dest = s->d1->handshake_fragment;
 979                         dest_len = &s->d1->handshake_fragment_len;
 980                         }
 981                 else if (rr->type == SSL3_RT_ALERT)
 982                         {
 983                         dest_maxlen = sizeof(s->d1->alert_fragment);
 984                         dest = s->d1->alert_fragment;
 985                         dest_len = &s->d1->alert_fragment_len;
 986                         }
 987 #ifndef OPENSSL_NO_HEARTBEATS
 988                 else if (rr->type == TLS1_RT_HEARTBEAT)
 989                         {
 990                         dtls1_process_heartbeat(s);
 991
 992                         /* Exit and notify application to read again */
 993                         rr->length = 0;
 994                         s->rwstate=SSL_READING;
 995                         BIO_clear_retry_flags(SSL_get_rbio(s));
 996                         BIO_set_retry_read(SSL_get_rbio(s));
 997                         return(-1);
 998                         }
 999 #endif
1000                 /* else it's a CCS message, or application data or wrong */
1001                 else if (rr->type != SSL3_RT_CHANGE_CIPHER_SPEC)
1002                         {
1003                         /* Application data while renegotiating
1004                          * is allowed. Try again reading.
1005                          */
1006                         if (rr->type == SSL3_RT_APPLICATION_DATA)
1007                                 {
1008                                 BIO *bio;
1009                                 s->s3->in_read_app_data=2;
1010                                 bio=SSL_get_rbio(s);
1011                                 s->rwstate=SSL_READING;
1012                                 BIO_clear_retry_flags(bio);
1013                                 BIO_set_retry_read(bio);
1014                                 return(-1);
1015                                 }
1016
1017                         /* Not certain if this is the right error handling */
1018                         al=SSL_AD_UNEXPECTED_MESSAGE;
1019                         SSLerr(SSL_F_DTLS1_READ_BYTES,SSL_R_UNEXPECTED_RECORD);
1020                         goto f_err;
1021                         }
1022
1023                 if (dest_maxlen > 0)
1024                         {
1025             /* XDTLS:  In a pathalogical case, the Client Hello
1026              *  may be fragmented--don't always expect dest_maxlen bytes */
1027                         if ( rr->length < dest_maxlen)
1028                                 {
1029 #ifdef DTLS1_AD_MISSING_HANDSHAKE_MESSAGE
1030                                 /*
1031                                  * for normal alerts rr->length is 2, while
1032                                  * dest_maxlen is 7 if we were to handle this
1033                                  * non-existing alert...
1034                                  */
1035                                 FIX ME
1036 #endif
1037                                 s->rstate=SSL_ST_READ_HEADER;
1038                                 rr->length = 0;
1039                                 goto start;
1040                                 }
1041
1042                         /* now move 'n' bytes: */
1043                         for ( k = 0; k < dest_maxlen; k++)
1044                                 {
1045                                 dest[k] = rr->data[rr->off++];
1046                                 rr->length--;
1047                                 }
1048                         *dest_len = dest_maxlen;
1049                         }
1050                 }
1051
1052         /*-
1053          * s->d1->handshake_fragment_len == 12  iff  rr->type == SSL3_RT_HANDSHAKE;
1054          * s->d1->alert_fragment_len == 7      iff  rr->type == SSL3_RT_ALERT.
1055          * (Possibly rr is 'empty' now, i.e. rr->length may be 0.)
1056          */
1057
1058         /* If we are a client, check for an incoming 'Hello Request': */
1059         if ((!s->server) &&
1060                 (s->d1->handshake_fragment_len >= DTLS1_HM_HEADER_LENGTH) &&
1061                 (s->d1->handshake_fragment[0] == SSL3_MT_HELLO_REQUEST) &&
1062                 (s->session != NULL) && (s->session->cipher != NULL))
1063                 {
1064                 s->d1->handshake_fragment_len = 0;
1065
1066                 if ((s->d1->handshake_fragment[1] != 0) ||
1067                         (s->d1->handshake_fragment[2] != 0) ||
1068                         (s->d1->handshake_fragment[3] != 0))
1069                         {
1070                         al=SSL_AD_DECODE_ERROR;
1071                         SSLerr(SSL_F_DTLS1_READ_BYTES,SSL_R_BAD_HELLO_REQUEST);
1072                         goto err;
1073                         }
1074
1075                 /* no need to check sequence number on HELLO REQUEST messages */
1076
1077                 if (s->msg_callback)
1078                         s->msg_callback(0, s->version, SSL3_RT_HANDSHAKE,
1079                                 s->d1->handshake_fragment, 4, s, s->msg_callback_arg);
1080
1081                 if (SSL_is_init_finished(s) &&
1082                         !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS) &&
1083                         !s->s3->renegotiate)
1084                         {
1085                         s->d1->handshake_read_seq++;
1086                         s->new_session = 1;
1087                         ssl3_renegotiate(s);
1088                         if (ssl3_renegotiate_check(s))
1089                                 {
1090                                 i=s->handshake_func(s);
1091                                 if (i < 0) return(i);
1092                                 if (i == 0)
1093                                         {
1094                                         SSLerr(SSL_F_DTLS1_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
1095                                         return(-1);
1096                                         }
1097
1098                                 if (!(s->mode & SSL_MODE_AUTO_RETRY))
1099                                         {
1100                                         if (s->s3->rbuf.left == 0) /* no read-ahead left? */
1101                                                 {
1102                                                 BIO *bio;
1103                                                 /* In the case where we try to read application data,
1104                                                  * but we trigger an SSL handshake, we return -1 with
1105                                                  * the retry option set.  Otherwise renegotiation may
1106                                                  * cause nasty problems in the blocking world */
1107                                                 s->rwstate=SSL_READING;
1108                                                 bio=SSL_get_rbio(s);
1109                                                 BIO_clear_retry_flags(bio);
1110                                                 BIO_set_retry_read(bio);
1111                                                 return(-1);
1112                                                 }
1113                                         }
1114                                 }
1115                         }
1116                 /* we either finished a handshake or ignored the request,
1117                  * now try again to obtain the (application) data we were asked for */
1118                 goto start;
1119                 }
1120
1121         if (s->d1->alert_fragment_len >= DTLS1_AL_HEADER_LENGTH)
1122                 {
1123                 int alert_level = s->d1->alert_fragment[0];
1124                 int alert_descr = s->d1->alert_fragment[1];
1125
1126                 s->d1->alert_fragment_len = 0;
1127
1128                 if (s->msg_callback)
1129                         s->msg_callback(0, s->version, SSL3_RT_ALERT,
1130                                 s->d1->alert_fragment, 2, s, s->msg_callback_arg);
1131
1132                 if (s->info_callback != NULL)
1133                         cb=s->info_callback;
1134                 else if (s->ctx->info_callback != NULL)
1135                         cb=s->ctx->info_callback;
1136
1137                 if (cb != NULL)
1138                         {
1139                         j = (alert_level << 8) | alert_descr;
1140                         cb(s, SSL_CB_READ_ALERT, j);
1141                         }
1142
1143                 if (alert_level == 1) /* warning */
1144                         {
1145                         s->s3->warn_alert = alert_descr;
1146                         if (alert_descr == SSL_AD_CLOSE_NOTIFY)
1147                                 {
1148 #ifndef OPENSSL_NO_SCTP
1149                                 /* With SCTP and streams the socket may deliver app data
1150                                  * after a close_notify alert. We have to check this
1151                                  * first so that nothing gets discarded.
1152                                  */
1153                                 if (BIO_dgram_is_sctp(SSL_get_rbio(s)) &&
1154                                         BIO_dgram_sctp_msg_waiting(SSL_get_rbio(s)))
1155                                         {
1156                                         s->d1->shutdown_received = 1;
1157                                         s->rwstate=SSL_READING;
1158                                         BIO_clear_retry_flags(SSL_get_rbio(s));
1159                                         BIO_set_retry_read(SSL_get_rbio(s));
1160                                         return -1;
1161                                         }
1162 #endif
1163                                 s->shutdown |= SSL_RECEIVED_SHUTDOWN;
1164                                 return(0);
1165                                 }
1166 #if 0
1167             /* XXX: this is a possible improvement in the future */
1168                         /* now check if it's a missing record */
1169                         if (alert_descr == DTLS1_AD_MISSING_HANDSHAKE_MESSAGE)
1170                                 {
1171                                 unsigned short seq;
1172                                 unsigned int frag_off;
1173                                 unsigned char *p = &(s->d1->alert_fragment[2]);
1174
1175                                 n2s(p, seq);
1176                                 n2l3(p, frag_off);
1177
1178                                 dtls1_retransmit_message(s,
1179                                                                                  dtls1_get_queue_priority(frag->msg_header.seq, 0),
1180                                                                                  frag_off, &found);
1181                                 if ( ! found  && SSL_in_init(s))
1182                                         {
1183                                         /* fprintf( stderr,"in init = %d\n", SSL_in_init(s)); */
1184                                         /* requested a message not yet sent,
1185                                            send an alert ourselves */
1186                                         ssl3_send_alert(s,SSL3_AL_WARNING,
1187                                                 DTLS1_AD_MISSING_HANDSHAKE_MESSAGE);
1188                                         }
1189                                 }
1190 #endif
1191                         }
1192                 else if (alert_level == 2) /* fatal */
1193                         {
1194                         char tmp[16];
1195
1196                         s->rwstate=SSL_NOTHING;
1197                         s->s3->fatal_alert = alert_descr;
1198                         SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_AD_REASON_OFFSET + alert_descr);
1199                         BIO_snprintf(tmp,sizeof tmp,"%d",alert_descr);
1200                         ERR_add_error_data(2,"SSL alert number ",tmp);
1201                         s->shutdown|=SSL_RECEIVED_SHUTDOWN;
1202                         SSL_CTX_remove_session(s->ctx,s->session);
1203                         return(0);
1204                         }
1205                 else
1206                         {
1207                         al=SSL_AD_ILLEGAL_PARAMETER;
1208                         SSLerr(SSL_F_DTLS1_READ_BYTES,SSL_R_UNKNOWN_ALERT_TYPE);
1209                         goto f_err;
1210                         }
1211
1212                 goto start;
1213                 }
1214
1215         if (s->shutdown & SSL_SENT_SHUTDOWN) /* but we have not received a shutdown */
1216                 {
1217                 s->rwstate=SSL_NOTHING;
1218                 rr->length=0;
1219                 return(0);
1220                 }
1221
1222         if (rr->type == SSL3_RT_CHANGE_CIPHER_SPEC)
1223                 {
1224                 struct ccs_header_st ccs_hdr;
1225                 unsigned int ccs_hdr_len = DTLS1_CCS_HEADER_LENGTH;
1226
1227                 dtls1_get_ccs_header(rr->data, &ccs_hdr);
1228
1229                 if (s->version == DTLS1_BAD_VER)
1230                         ccs_hdr_len = 3;
1231
1232                 /* 'Change Cipher Spec' is just a single byte, so we know
1233                  * exactly what the record payload has to look like */
1234                 /* XDTLS: check that epoch is consistent */
1235                 if (    (rr->length != ccs_hdr_len) ||
1236                         (rr->off != 0) || (rr->data[0] != SSL3_MT_CCS))
1237                         {
1238                         i=SSL_AD_ILLEGAL_PARAMETER;
1239                         SSLerr(SSL_F_DTLS1_READ_BYTES,SSL_R_BAD_CHANGE_CIPHER_SPEC);
1240                         goto err;
1241                         }
1242
1243                 rr->length=0;
1244
1245                 if (s->msg_callback)
1246                         s->msg_callback(0, s->version, SSL3_RT_CHANGE_CIPHER_SPEC,
1247                                 rr->data, 1, s, s->msg_callback_arg);
1248
1249                 /* We can't process a CCS now, because previous handshake
1250                  * messages are still missing, so just drop it.
1251                  */
1252                 if (!s->d1->change_cipher_spec_ok)
1253                         {
1254                         goto start;
1255                         }
1256
1257                 s->d1->change_cipher_spec_ok = 0;
1258
1259                 s->s3->change_cipher_spec=1;
1260                 if (!ssl3_do_change_cipher_spec(s))
1261                         goto err;
1262
1263                 /* do this whenever CCS is processed */
1264                 dtls1_reset_seq_numbers(s, SSL3_CC_READ);
1265
1266                 if (s->version == DTLS1_BAD_VER)
1267                         s->d1->handshake_read_seq++;
1268
1269 #ifndef OPENSSL_NO_SCTP
1270                 /* Remember that a CCS has been received,
1271                  * so that an old key of SCTP-Auth can be
1272                  * deleted when a CCS is sent. Will be ignored
1273                  * if no SCTP is used
1274                  */
1275                 BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_AUTH_CCS_RCVD, 1, NULL);
1276 #endif
1277
1278                 goto start;
1279                 }
1280
1281         /* Unexpected handshake message (Client Hello, or protocol violation) */
1282         if ((s->d1->handshake_fragment_len >= DTLS1_HM_HEADER_LENGTH) &&
1283                 !s->in_handshake)
1284                 {
1285                 struct hm_header_st msg_hdr;
1286
1287                 /* this may just be a stale retransmit */
1288                 dtls1_get_message_header(rr->data, &msg_hdr);
1289                 if( rr->epoch != s->d1->r_epoch)
1290                         {
1291                         rr->length = 0;
1292                         goto start;
1293                         }
1294
1295                 /* If we are server, we may have a repeated FINISHED of the
1296                  * client here, then retransmit our CCS and FINISHED.
1297                  */
1298                 if (msg_hdr.type == SSL3_MT_FINISHED)
1299                         {
1300                         if (dtls1_check_timeout_num(s) < 0)
1301                                 return -1;
1302
1303                         dtls1_retransmit_buffered_messages(s);
1304                         rr->length = 0;
1305                         goto start;
1306                         }
1307
1308                 if (((s->state&SSL_ST_MASK) == SSL_ST_OK) &&
1309                         !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS))
1310                         {
1311 #if 0 /* worked only because C operator preferences are not as expected (and
1312        * because this is not really needed for clients except for detecting
1313        * protocol violations): */
1314                         s->state=SSL_ST_BEFORE|(s->server)
1315                                 ?SSL_ST_ACCEPT
1316                                 :SSL_ST_CONNECT;
1317 #else
1318                         s->state = s->server ? SSL_ST_ACCEPT : SSL_ST_CONNECT;
1319 #endif
1320                         s->renegotiate=1;
1321                         s->new_session=1;
1322                         }
1323                 i=s->handshake_func(s);
1324                 if (i < 0) return(i);
1325                 if (i == 0)
1326                         {
1327                         SSLerr(SSL_F_DTLS1_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
1328                         return(-1);
1329                         }
1330
1331                 if (!(s->mode & SSL_MODE_AUTO_RETRY))
1332                         {
1333                         if (s->s3->rbuf.left == 0) /* no read-ahead left? */
1334                                 {
1335                                 BIO *bio;
1336                                 /* In the case where we try to read application data,
1337                                  * but we trigger an SSL handshake, we return -1 with
1338                                  * the retry option set.  Otherwise renegotiation may
1339                                  * cause nasty problems in the blocking world */
1340                                 s->rwstate=SSL_READING;
1341                                 bio=SSL_get_rbio(s);
1342                                 BIO_clear_retry_flags(bio);
1343                                 BIO_set_retry_read(bio);
1344                                 return(-1);
1345                                 }
1346                         }
1347                 goto start;
1348                 }
1349
1350         switch (rr->type)
1351                 {
1352         default:
1353 #ifndef OPENSSL_NO_TLS
1354                 /* TLS just ignores unknown message types */
1355                 if (s->version == TLS1_VERSION)
1356                         {
1357                         rr->length = 0;
1358                         goto start;
1359                         }
1360 #endif
1361                 al=SSL_AD_UNEXPECTED_MESSAGE;
1362                 SSLerr(SSL_F_DTLS1_READ_BYTES,SSL_R_UNEXPECTED_RECORD);
1363                 goto f_err;
1364         case SSL3_RT_CHANGE_CIPHER_SPEC:
1365         case SSL3_RT_ALERT:
1366         case SSL3_RT_HANDSHAKE:
1367                 /* we already handled all of these, with the possible exception
1368                  * of SSL3_RT_HANDSHAKE when s->in_handshake is set, but that
1369                  * should not happen when type != rr->type */
1370                 al=SSL_AD_UNEXPECTED_MESSAGE;
1371                 SSLerr(SSL_F_DTLS1_READ_BYTES,ERR_R_INTERNAL_ERROR);
1372                 goto f_err;
1373         case SSL3_RT_APPLICATION_DATA:
1374                 /* At this point, we were expecting handshake data,
1375                  * but have application data.  If the library was
1376                  * running inside ssl3_read() (i.e. in_read_app_data
1377                  * is set) and it makes sense to read application data
1378                  * at this point (session renegotiation not yet started),
1379                  * we will indulge it.
1380                  */
1381                 if (s->s3->in_read_app_data &&
1382                         (s->s3->total_renegotiations != 0) &&
1383                         ((
1384                                 (s->state & SSL_ST_CONNECT) &&
1385                                 (s->state >= SSL3_ST_CW_CLNT_HELLO_A) &&
1386                                 (s->state <= SSL3_ST_CR_SRVR_HELLO_A)
1387                                 ) || (
1388                                         (s->state & SSL_ST_ACCEPT) &&
1389                                         (s->state <= SSL3_ST_SW_HELLO_REQ_A) &&
1390                                         (s->state >= SSL3_ST_SR_CLNT_HELLO_A)
1391                                         )
1392                                 ))
1393                         {
1394                         s->s3->in_read_app_data=2;
1395                         return(-1);
1396                         }
1397                 else
1398                         {
1399                         al=SSL_AD_UNEXPECTED_MESSAGE;
1400                         SSLerr(SSL_F_DTLS1_READ_BYTES,SSL_R_UNEXPECTED_RECORD);
1401                         goto f_err;
1402                         }
1403                 }
1404         /* not reached */
1405
1406 f_err:
1407         ssl3_send_alert(s,SSL3_AL_FATAL,al);
1408 err:
1409         return(-1);
1410         }
1411
1412 int
1413 dtls1_write_app_data_bytes(SSL *s, int type, const void *buf_, int len)
1414         {
1415         int i;
1416
1417 #ifndef OPENSSL_NO_SCTP
1418                 /* Check if we have to continue an interrupted handshake
1419                  * for reading belated app data with SCTP.
1420                  */
1421                 if ((SSL_in_init(s) && !s->in_handshake) ||
1422                     (BIO_dgram_is_sctp(SSL_get_wbio(s)) &&
1423                      (s->state == DTLS1_SCTP_ST_SR_READ_SOCK || s->state == DTLS1_SCTP_ST_CR_READ_SOCK)))
1424 #else
1425                 if (SSL_in_init(s) && !s->in_handshake)
1426 #endif
1427                 {
1428                 i=s->handshake_func(s);
1429                 if (i < 0) return(i);
1430                 if (i == 0)
1431                         {
1432                         SSLerr(SSL_F_DTLS1_WRITE_APP_DATA_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
1433                         return -1;
1434                         }
1435                 }
1436
1437         if (len > SSL3_RT_MAX_PLAIN_LENGTH)
1438                 {
1439                         SSLerr(SSL_F_DTLS1_WRITE_APP_DATA_BYTES,SSL_R_DTLS_MESSAGE_TOO_BIG);
1440                         return -1;
1441                 }
1442
1443         i = dtls1_write_bytes(s, type, buf_, len);
1444         return i;
1445         }
1446
1447
1448         /* this only happens when a client hello is received and a handshake
1449          * is started. */
1450 static int
1451 have_handshake_fragment(SSL *s, int type, unsigned char *buf,
1452         int len, int peek)
1453         {
1454
1455         if ((type == SSL3_RT_HANDSHAKE) && (s->d1->handshake_fragment_len > 0))
1456                 /* (partially) satisfy request from storage */
1457                 {
1458                 unsigned char *src = s->d1->handshake_fragment;
1459                 unsigned char *dst = buf;
1460                 unsigned int k,n;
1461
1462                 /* peek == 0 */
1463                 n = 0;
1464                 while ((len > 0) && (s->d1->handshake_fragment_len > 0))
1465                         {
1466                         *dst++ = *src++;
1467                         len--; s->d1->handshake_fragment_len--;
1468                         n++;
1469                         }
1470                 /* move any remaining fragment bytes: */
1471                 for (k = 0; k < s->d1->handshake_fragment_len; k++)
1472                         s->d1->handshake_fragment[k] = *src++;
1473                 return n;
1474                 }
1475
1476         return 0;
1477         }
1478
1479
1480
1481
1482 /* Call this to write data in records of type 'type'
1483  * It will return <= 0 if not all data has been sent or non-blocking IO.
1484  */
1485 int dtls1_write_bytes(SSL *s, int type, const void *buf, int len)
1486         {
1487         int i;
1488
1489         OPENSSL_assert(len <= SSL3_RT_MAX_PLAIN_LENGTH);
1490         s->rwstate=SSL_NOTHING;
1491         i=do_dtls1_write(s, type, buf, len, 0);
1492         return i;
1493         }
1494
1495 int do_dtls1_write(SSL *s, int type, const unsigned char *buf, unsigned int len, int create_empty_fragment)
1496         {
1497         unsigned char *p,*pseq;
1498         int i,mac_size,clear=0;
1499         int prefix_len = 0;
1500         int eivlen;
1501         SSL3_RECORD *wr;
1502         SSL3_BUFFER *wb;
1503         SSL_SESSION *sess;
1504
1505         /* first check if there is a SSL3_BUFFER still being written
1506          * out.  This will happen with non blocking IO */
1507         if (s->s3->wbuf.left != 0)
1508                 {
1509                 OPENSSL_assert(0); /* XDTLS:  want to see if we ever get here */
1510                 return(ssl3_write_pending(s,type,buf,len));
1511                 }
1512
1513         /* If we have an alert to send, lets send it */
1514         if (s->s3->alert_dispatch)
1515                 {
1516                 i=s->method->ssl_dispatch_alert(s);
1517                 if (i <= 0)
1518                         return(i);
1519                 /* if it went, fall through and send more stuff */
1520                 }
1521
1522         if (len == 0 && !create_empty_fragment)
1523                 return 0;
1524
1525         wr= &(s->s3->wrec);
1526         wb= &(s->s3->wbuf);
1527         sess=s->session;
1528
1529         if (    (sess == NULL) ||
1530                 (s->enc_write_ctx == NULL) ||
1531                 (EVP_MD_CTX_md(s->write_hash) == NULL))
1532                 clear=1;
1533
1534         if (clear)
1535                 mac_size=0;
1536         else
1537                 {
1538                 mac_size=EVP_MD_CTX_size(s->write_hash);
1539                 if (mac_size < 0)
1540                         goto err;
1541                 }
1542
1543         /* DTLS implements explicit IV, so no need for empty fragments */
1544 #if 0
1545         /* 'create_empty_fragment' is true only when this function calls itself */
1546         if (!clear && !create_empty_fragment && !s->s3->empty_fragment_done
1547             && SSL_version(s) != DTLS1_VERSION && SSL_version(s) != DTLS1_BAD_VER)
1548                 {
1549                 /* countermeasure against known-IV weakness in CBC ciphersuites
1550                  * (see http://www.openssl.org/~bodo/tls-cbc.txt)
1551                  */
1552
1553                 if (s->s3->need_empty_fragments && type == SSL3_RT_APPLICATION_DATA)
1554                         {
1555                         /* recursive function call with 'create_empty_fragment' set;
1556                          * this prepares and buffers the data for an empty fragment
1557                          * (these 'prefix_len' bytes are sent out later
1558                          * together with the actual payload) */
1559                         prefix_len = s->method->do_ssl_write(s, type, buf, 0, 1);
1560                         if (prefix_len <= 0)
1561                                 goto err;
1562
1563                         if (s->s3->wbuf.len < (size_t)prefix_len + SSL3_RT_MAX_PACKET_SIZE)
1564                                 {
1565                                 /* insufficient space */
1566                                 SSLerr(SSL_F_DO_DTLS1_WRITE, ERR_R_INTERNAL_ERROR);
1567                                 goto err;
1568                                 }
1569                         }
1570
1571                 s->s3->empty_fragment_done = 1;
1572                 }
1573 #endif
1574         p = wb->buf + prefix_len;
1575
1576         /* write the header */
1577
1578         *(p++)=type&0xff;
1579         wr->type=type;
1580         /* Special case: for hello verify request, client version 1.0 and
1581          * we haven't decided which version to use yet send back using
1582          * version 1.0 header: otherwise some clients will ignore it.
1583          */
1584         if (s->method->version == DTLS_ANY_VERSION)
1585                 {
1586                 *(p++)=DTLS1_VERSION>>8;
1587                 *(p++)=DTLS1_VERSION&0xff;
1588                 }
1589         else
1590                 {
1591                 *(p++)=s->version>>8;
1592                 *(p++)=s->version&0xff;
1593                 }
1594
1595         /* field where we are to write out packet epoch, seq num and len */
1596         pseq=p;
1597         p+=10;
1598
1599         /* Explicit IV length, block ciphers appropriate version flag */
1600         if (s->enc_write_ctx)
1601                 {
1602                 int mode = EVP_CIPHER_CTX_mode(s->enc_write_ctx);
1603                 if (mode == EVP_CIPH_CBC_MODE)
1604                         {
1605                         eivlen = EVP_CIPHER_CTX_iv_length(s->enc_write_ctx);
1606                         if (eivlen <= 1)
1607                                 eivlen = 0;
1608                         }
1609                 /* Need explicit part of IV for GCM mode */
1610                 else if (mode == EVP_CIPH_GCM_MODE)
1611                         eivlen = EVP_GCM_TLS_EXPLICIT_IV_LEN;
1612                 else
1613                         eivlen = 0;
1614                 }
1615         else
1616                 eivlen = 0;
1617
1618         /* lets setup the record stuff. */
1619         wr->data=p + eivlen;  /* make room for IV in case of CBC */
1620         wr->length=(int)len;
1621         wr->input=(unsigned char *)buf;
1622
1623         /* we now 'read' from wr->input, wr->length bytes into
1624          * wr->data */
1625
1626         /* first we compress */
1627         if (s->compress != NULL)
1628                 {
1629                 if (!ssl3_do_compress(s))
1630                         {
1631                         SSLerr(SSL_F_DO_DTLS1_WRITE,SSL_R_COMPRESSION_FAILURE);
1632                         goto err;
1633                         }
1634                 }
1635         else
1636                 {
1637                 memcpy(wr->data,wr->input,wr->length);
1638                 wr->input=wr->data;
1639                 }
1640
1641         /* we should still have the output to wr->data and the input
1642          * from wr->input.  Length should be wr->length.
1643          * wr->data still points in the wb->buf */
1644
1645         if (mac_size != 0)
1646                 {
1647                 if(s->method->ssl3_enc->mac(s,&(p[wr->length + eivlen]),1) < 0)
1648                         goto err;
1649                 wr->length+=mac_size;
1650                 }
1651
1652         /* this is true regardless of mac size */
1653         wr->input=p;
1654         wr->data=p;
1655
1656         if (eivlen)
1657                 wr->length += eivlen;
1658
1659         if(s->method->ssl3_enc->enc(s,1) < 1) goto err;
1660
1661         /* record length after mac and block padding */
1662 /*      if (type == SSL3_RT_APPLICATION_DATA ||
1663         (type == SSL3_RT_ALERT && ! SSL_in_init(s))) */
1664
1665         /* there's only one epoch between handshake and app data */
1666
1667         s2n(s->d1->w_epoch, pseq);
1668
1669         /* XDTLS: ?? */
1670 /*      else
1671         s2n(s->d1->handshake_epoch, pseq); */
1672
1673         memcpy(pseq, &(s->s3->write_sequence[2]), 6);
1674         pseq+=6;
1675         s2n(wr->length,pseq);
1676
1677         if (s->msg_callback)
1678                 s->msg_callback(1, 0, SSL3_RT_HEADER, pseq - DTLS1_RT_HEADER_LENGTH, DTLS1_RT_HEADER_LENGTH, s, s->msg_callback_arg);
1679
1680         /* we should now have
1681          * wr->data pointing to the encrypted data, which is
1682          * wr->length long */
1683         wr->type=type; /* not needed but helps for debugging */
1684         wr->length+=DTLS1_RT_HEADER_LENGTH;
1685
1686 #if 0  /* this is now done at the message layer */
1687         /* buffer the record, making it easy to handle retransmits */
1688         if ( type == SSL3_RT_HANDSHAKE || type == SSL3_RT_CHANGE_CIPHER_SPEC)
1689                 dtls1_buffer_record(s, wr->data, wr->length,
1690                         *((PQ_64BIT *)&(s->s3->write_sequence[0])));
1691 #endif
1692
1693         ssl3_record_sequence_update(&(s->s3->write_sequence[0]));
1694
1695         if (create_empty_fragment)
1696                 {
1697                 /* we are in a recursive call;
1698                  * just return the length, don't write out anything here
1699                  */
1700                 return wr->length;
1701                 }
1702
1703         /* now let's set up wb */
1704         wb->left = prefix_len + wr->length;
1705         wb->offset = 0;
1706
1707         /* memorize arguments so that ssl3_write_pending can detect bad write retries later */
1708         s->s3->wpend_tot=len;
1709         s->s3->wpend_buf=buf;
1710         s->s3->wpend_type=type;
1711         s->s3->wpend_ret=len;
1712
1713         /* we now just need to write the buffer */
1714         return ssl3_write_pending(s,type,buf,len);
1715 err:
1716         return -1;
1717         }
1718
1719
1720
1721 static int dtls1_record_replay_check(SSL *s, DTLS1_BITMAP *bitmap)
1722         {
1723         int cmp;
1724         unsigned int shift;
1725         const unsigned char *seq = s->s3->read_sequence;
1726
1727         cmp = satsub64be(seq,bitmap->max_seq_num);
1728         if (cmp > 0)
1729                 {
1730                 memcpy (s->s3->rrec.seq_num,seq,8);
1731                 return 1; /* this record in new */
1732                 }
1733         shift = -cmp;
1734         if (shift >= sizeof(bitmap->map)*8)
1735                 return 0; /* stale, outside the window */
1736         else if (bitmap->map & (1UL<<shift))
1737                 return 0; /* record previously received */
1738
1739         memcpy (s->s3->rrec.seq_num,seq,8);
1740         return 1;
1741         }
1742
1743
1744 static void dtls1_record_bitmap_update(SSL *s, DTLS1_BITMAP *bitmap)
1745         {
1746         int cmp;
1747         unsigned int shift;
1748         const unsigned char *seq = s->s3->read_sequence;
1749
1750         cmp = satsub64be(seq,bitmap->max_seq_num);
1751         if (cmp > 0)
1752                 {
1753                 shift = cmp;
1754                 if (shift < sizeof(bitmap->map)*8)
1755                         bitmap->map <<= shift, bitmap->map |= 1UL;
1756                 else
1757                         bitmap->map = 1UL;
1758                 memcpy(bitmap->max_seq_num,seq,8);
1759                 }
1760         else    {
1761                 shift = -cmp;
1762                 if (shift < sizeof(bitmap->map)*8)
1763                         bitmap->map |= 1UL<<shift;
1764                 }
1765         }
1766
1767
1768 int dtls1_dispatch_alert(SSL *s)
1769         {
1770         int i,j;
1771         void (*cb)(const SSL *ssl,int type,int val)=NULL;
1772         unsigned char buf[DTLS1_AL_HEADER_LENGTH];
1773         unsigned char *ptr = &buf[0];
1774
1775         s->s3->alert_dispatch=0;
1776
1777         memset(buf, 0x00, sizeof(buf));
1778         *ptr++ = s->s3->send_alert[0];
1779         *ptr++ = s->s3->send_alert[1];
1780
1781 #ifdef DTLS1_AD_MISSING_HANDSHAKE_MESSAGE
1782         if (s->s3->send_alert[1] == DTLS1_AD_MISSING_HANDSHAKE_MESSAGE)
1783                 {
1784                 s2n(s->d1->handshake_read_seq, ptr);
1785 #if 0
1786                 if ( s->d1->r_msg_hdr.frag_off == 0)  /* waiting for a new msg */
1787
1788                 else
1789                         s2n(s->d1->r_msg_hdr.seq, ptr); /* partial msg read */
1790 #endif
1791
1792 #if 0
1793                 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);
1794 #endif
1795                 l2n3(s->d1->r_msg_hdr.frag_off, ptr);
1796                 }
1797 #endif
1798
1799         i = do_dtls1_write(s, SSL3_RT_ALERT, &buf[0], sizeof(buf), 0);
1800         if (i <= 0)
1801                 {
1802                 s->s3->alert_dispatch=1;
1803                 /* fprintf( stderr, "not done with alert\n" ); */
1804                 }
1805         else
1806                 {
1807                 if (s->s3->send_alert[0] == SSL3_AL_FATAL
1808 #ifdef DTLS1_AD_MISSING_HANDSHAKE_MESSAGE
1809                     || s->s3->send_alert[1] == DTLS1_AD_MISSING_HANDSHAKE_MESSAGE
1810 #endif
1811                     )
1812                         (void)BIO_flush(s->wbio);
1813
1814                 if (s->msg_callback)
1815                         s->msg_callback(1, s->version, SSL3_RT_ALERT, s->s3->send_alert,
1816                                 2, s, s->msg_callback_arg);
1817
1818                 if (s->info_callback != NULL)
1819                         cb=s->info_callback;
1820                 else if (s->ctx->info_callback != NULL)
1821                         cb=s->ctx->info_callback;
1822
1823                 if (cb != NULL)
1824                         {
1825                         j=(s->s3->send_alert[0]<<8)|s->s3->send_alert[1];
1826                         cb(s,SSL_CB_WRITE_ALERT,j);
1827                         }
1828                 }
1829         return(i);
1830         }
1831
1832
1833 static DTLS1_BITMAP *
1834 dtls1_get_bitmap(SSL *s, SSL3_RECORD *rr, unsigned int *is_next_epoch)
1835     {
1836
1837     *is_next_epoch = 0;
1838
1839     /* In current epoch, accept HM, CCS, DATA, & ALERT */
1840     if (rr->epoch == s->d1->r_epoch)
1841         return &s->d1->bitmap;
1842
1843     /* Only HM and ALERT messages can be from the next epoch */
1844     else if (rr->epoch == (unsigned long)(s->d1->r_epoch + 1) &&
1845         (rr->type == SSL3_RT_HANDSHAKE ||
1846             rr->type == SSL3_RT_ALERT))
1847         {
1848         *is_next_epoch = 1;
1849         return &s->d1->next_bitmap;
1850         }
1851
1852     return NULL;
1853     }
1854
1855 #if 0
1856 static int
1857 dtls1_record_needs_buffering(SSL *s, SSL3_RECORD *rr, unsigned short *priority,
1858         unsigned long *offset)
1859         {
1860
1861         /* alerts are passed up immediately */
1862         if ( rr->type == SSL3_RT_APPLICATION_DATA ||
1863                 rr->type == SSL3_RT_ALERT)
1864                 return 0;
1865
1866         /* Only need to buffer if a handshake is underway.
1867          * (this implies that Hello Request and Client Hello are passed up
1868          * immediately) */
1869         if ( SSL_in_init(s))
1870                 {
1871                 unsigned char *data = rr->data;
1872                 /* need to extract the HM/CCS sequence number here */
1873                 if ( rr->type == SSL3_RT_HANDSHAKE ||
1874                         rr->type == SSL3_RT_CHANGE_CIPHER_SPEC)
1875                         {
1876                         unsigned short seq_num;
1877                         struct hm_header_st msg_hdr;
1878                         struct ccs_header_st ccs_hdr;
1879
1880                         if ( rr->type == SSL3_RT_HANDSHAKE)
1881                                 {
1882                                 dtls1_get_message_header(data, &msg_hdr);
1883                                 seq_num = msg_hdr.seq;
1884                                 *offset = msg_hdr.frag_off;
1885                                 }
1886                         else
1887                                 {
1888                                 dtls1_get_ccs_header(data, &ccs_hdr);
1889                                 seq_num = ccs_hdr.seq;
1890                                 *offset = 0;
1891                                 }
1892
1893                         /* this is either a record we're waiting for, or a
1894                          * retransmit of something we happened to previously
1895                          * receive (higher layers will drop the repeat silently */
1896                         if ( seq_num < s->d1->handshake_read_seq)
1897                                 return 0;
1898                         if (rr->type == SSL3_RT_HANDSHAKE &&
1899                                 seq_num == s->d1->handshake_read_seq &&
1900                                 msg_hdr.frag_off < s->d1->r_msg_hdr.frag_off)
1901                                 return 0;
1902                         else if ( seq_num == s->d1->handshake_read_seq &&
1903                                 (rr->type == SSL3_RT_CHANGE_CIPHER_SPEC ||
1904                                         msg_hdr.frag_off == s->d1->r_msg_hdr.frag_off))
1905                                 return 0;
1906                         else
1907                                 {
1908                                 *priority = seq_num;
1909                                 return 1;
1910                                 }
1911                         }
1912                 else /* unknown record type */
1913                         return 0;
1914                 }
1915
1916         return 0;
1917         }
1918 #endif
1919
1920 void
1921 dtls1_reset_seq_numbers(SSL *s, int rw)
1922         {
1923         unsigned char *seq;
1924         unsigned int seq_bytes = sizeof(s->s3->read_sequence);
1925
1926         if ( rw & SSL3_CC_READ)
1927                 {
1928                 seq = s->s3->read_sequence;
1929                 s->d1->r_epoch++;
1930                 memcpy(&(s->d1->bitmap), &(s->d1->next_bitmap), sizeof(DTLS1_BITMAP));
1931                 memset(&(s->d1->next_bitmap), 0x00, sizeof(DTLS1_BITMAP));
1932                 }
1933         else
1934                 {
1935                 seq = s->s3->write_sequence;
1936                 memcpy(s->d1->last_write_sequence, seq, sizeof(s->s3->write_sequence));
1937                 s->d1->w_epoch++;
1938                 }
1939
1940         memset(seq, 0x00, seq_bytes);
1941         }