ssl/d1_pkt.c

   1 /* ssl/d1_pkt.c */
   2 /*
   3  * DTLS implementation written by Nagendra Modadugu
   4  * (nagendra@cs.stanford.edu) for the OpenSSL project 2005.
   5  */
   6 /* ====================================================================
   7  * Copyright (c) 1998-2005 The OpenSSL Project.  All rights reserved.
   8  *
   9  * Redistribution and use in source and binary forms, with or without
  10  * modification, are permitted provided that the following conditions
  11  * are met:
  12  *
  13  * 1. Redistributions of source code must retain the above copyright
  14  *    notice, this list of conditions and the following disclaimer.
  15  *
  16  * 2. Redistributions in binary form must reproduce the above copyright
  17  *    notice, this list of conditions and the following disclaimer in
  18  *    the documentation and/or other materials provided with the
  19  *    distribution.
  20  *
  21  * 3. All advertising materials mentioning features or use of this
  22  *    software must display the following acknowledgment:
  23  *    "This product includes software developed by the OpenSSL Project
  24  *    for use in the OpenSSL Toolkit. (http://www.openssl.org/)"
  25  *
  26  * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
  27  *    endorse or promote products derived from this software without
  28  *    prior written permission. For written permission, please contact
  29  *    openssl-core@openssl.org.
  30  *
  31  * 5. Products derived from this software may not be called "OpenSSL"
  32  *    nor may "OpenSSL" appear in their names without prior written
  33  *    permission of the OpenSSL Project.
  34  *
  35  * 6. Redistributions of any form whatsoever must retain the following
  36  *    acknowledgment:
  37  *    "This product includes software developed by the OpenSSL Project
  38  *    for use in the OpenSSL Toolkit (http://www.openssl.org/)"
  39  *
  40  * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
  41  * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  42  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  43  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
  44  * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  45  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  46  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  47  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  48  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
  49  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  50  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
  51  * OF THE POSSIBILITY OF SUCH DAMAGE.
  52  * ====================================================================
  53  *
  54  * This product includes cryptographic software written by Eric Young
  55  * (eay@cryptsoft.com).  This product includes software written by Tim
  56  * Hudson (tjh@cryptsoft.com).
  57  *
  58  */
  59 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
  60  * All rights reserved.
  61  *
  62  * This package is an SSL implementation written
  63  * by Eric Young (eay@cryptsoft.com).
  64  * The implementation was written so as to conform with Netscapes SSL.
  65  *
  66  * This library is free for commercial and non-commercial use as long as
  67  * the following conditions are aheared to.  The following conditions
  68  * apply to all code found in this distribution, be it the RC4, RSA,
  69  * lhash, DES, etc., code; not just the SSL code.  The SSL documentation
  70  * included with this distribution is covered by the same copyright terms
  71  * except that the holder is Tim Hudson (tjh@cryptsoft.com).
  72  *
  73  * Copyright remains Eric Young's, and as such any Copyright notices in
  74  * the code are not to be removed.
  75  * If this package is used in a product, Eric Young should be given attribution
  76  * as the author of the parts of the library used.
  77  * This can be in the form of a textual message at program startup or
  78  * in documentation (online or textual) provided with the package.
  79  *
  80  * Redistribution and use in source and binary forms, with or without
  81  * modification, are permitted provided that the following conditions
  82  * are met:
  83  * 1. Redistributions of source code must retain the copyright
  84  *    notice, this list of conditions and the following disclaimer.
  85  * 2. Redistributions in binary form must reproduce the above copyright
  86  *    notice, this list of conditions and the following disclaimer in the
  87  *    documentation and/or other materials provided with the distribution.
  88  * 3. All advertising materials mentioning features or use of this software
  89  *    must display the following acknowledgement:
  90  *    "This product includes cryptographic software written by
  91  *     Eric Young (eay@cryptsoft.com)"
  92  *    The word 'cryptographic' can be left out if the rouines from the library
  93  *    being used are not cryptographic related :-).
  94  * 4. If you include any Windows specific code (or a derivative thereof) from
  95  *    the apps directory (application code) you must include an acknowledgement:
  96  *    "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
  97  *
  98  * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
  99  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 100  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 101  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
 102  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 103  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 104  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 105  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 106  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 107  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 108  * SUCH DAMAGE.
 109  *
 110  * The licence and distribution terms for any publically available version or
 111  * derivative of this code cannot be changed.  i.e. this code cannot simply be
 112  * copied and put under another distribution licence
 113  * [including the GNU Public Licence.]
 114  */
 115
 116 #include <stdio.h>
 117 #include <errno.h>
 118 #define USE_SOCKETS
 119 #include "ssl_locl.h"
 120 #include <openssl/evp.h>
 121 #include <openssl/buffer.h>
 122 #include <openssl/pqueue.h>
 123 #include <openssl/rand.h>
 124
 125 /* mod 128 saturating subtract of two 64-bit values in big-endian order */
 126 static int satsub64be(const unsigned char *v1,const unsigned char *v2)
 127 {       int ret,sat,brw,i;
 128
 129         if (sizeof(long) == 8) do
 130         {       const union { long one; char little; } is_endian = {1};
 131                 long l;
 132
 133                 if (is_endian.little)                   break;
 134                 /* not reached on little-endians */
 135                 /* following test is redundant, because input is
 136                  * always aligned, but I take no chances... */
 137                 if (((size_t)v1|(size_t)v2)&0x7)        break;
 138
 139                 l  = *((long *)v1);
 140                 l -= *((long *)v2);
 141                 if (l>128)              return 128;
 142                 else if (l<-128)        return -128;
 143                 else                    return (int)l;
 144         } while (0);
 145
 146         ret = (int)v1[7]-(int)v2[7];
 147         sat = 0;
 148         brw = ret>>8;   /* brw is either 0 or -1 */
 149         if (ret & 0x80)
 150         {       for (i=6;i>=0;i--)
 151                 {       brw += (int)v1[i]-(int)v2[i];
 152                         sat |= ~brw;
 153                         brw >>= 8;
 154                 }
 155         }
 156         else
 157         {       for (i=6;i>=0;i--)
 158                 {       brw += (int)v1[i]-(int)v2[i];
 159                         sat |= brw;
 160                         brw >>= 8;
 161                 }
 162         }
 163         brw <<= 8;      /* brw is either 0 or -256 */
 164
 165         if (sat&0xff)   return brw | 0x80;
 166         else            return brw + (ret&0xFF);
 167 }
 168
 169 static int have_handshake_fragment(SSL *s, int type, unsigned char *buf,
 170         int len, int peek);
 171 static int dtls1_record_replay_check(SSL *s, DTLS1_BITMAP *bitmap);
 172 static void dtls1_record_bitmap_update(SSL *s, DTLS1_BITMAP *bitmap);
 173 static DTLS1_BITMAP *dtls1_get_bitmap(SSL *s, SSL3_RECORD *rr,
 174     unsigned int *is_next_epoch);
 175 #if 0
 176 static int dtls1_record_needs_buffering(SSL *s, SSL3_RECORD *rr,
 177         unsigned short *priority, unsigned long *offset);
 178 #endif
 179 static int dtls1_buffer_record(SSL *s, record_pqueue *q,
 180         unsigned char *priority);
 181 static int dtls1_process_record(SSL *s);
 182
 183 /* copy buffered record into SSL structure */
 184 static int
 185 dtls1_copy_record(SSL *s, pitem *item)
 186     {
 187     DTLS1_RECORD_DATA *rdata;
 188
 189     rdata = (DTLS1_RECORD_DATA *)item->data;
 190
 191     if (s->s3->rbuf.buf != NULL)
 192         OPENSSL_free(s->s3->rbuf.buf);
 193
 194     s->packet = rdata->packet;
 195     s->packet_length = rdata->packet_length;
 196     memcpy(&(s->s3->rbuf), &(rdata->rbuf), sizeof(SSL3_BUFFER));
 197     memcpy(&(s->s3->rrec), &(rdata->rrec), sizeof(SSL3_RECORD));
 198
 199         /* Set proper sequence number for mac calculation */
 200         memcpy(&(s->s3->read_sequence[2]), &(rdata->packet[5]), 6);
 201
 202     return(1);
 203     }
 204
 205
 206 static int
 207 dtls1_buffer_record(SSL *s, record_pqueue *queue, unsigned char *priority)
 208         {
 209         DTLS1_RECORD_DATA *rdata;
 210         pitem *item;
 211
 212         /* Limit the size of the queue to prevent DOS attacks */
 213         if (pqueue_size(queue->q) >= 100)
 214                 return 0;
 215
 216         rdata = OPENSSL_malloc(sizeof(DTLS1_RECORD_DATA));
 217         item = pitem_new(priority, rdata);
 218         if (rdata == NULL || item == NULL)
 219                 {
 220                 if (rdata != NULL) OPENSSL_free(rdata);
 221                 if (item != NULL) pitem_free(item);
 222
 223                 SSLerr(SSL_F_DTLS1_BUFFER_RECORD, ERR_R_INTERNAL_ERROR);
 224                 return(0);
 225                 }
 226
 227         rdata->packet = s->packet;
 228         rdata->packet_length = s->packet_length;
 229         memcpy(&(rdata->rbuf), &(s->s3->rbuf), sizeof(SSL3_BUFFER));
 230         memcpy(&(rdata->rrec), &(s->s3->rrec), sizeof(SSL3_RECORD));
 231
 232         item->data = rdata;
 233
 234 #ifndef OPENSSL_NO_SCTP
 235         /* Store bio_dgram_sctp_rcvinfo struct */
 236         if (BIO_dgram_is_sctp(SSL_get_rbio(s)) &&
 237             (s->state == SSL3_ST_SR_FINISHED_A || s->state == SSL3_ST_CR_FINISHED_A)) {
 238                 BIO_ctrl(SSL_get_rbio(s), BIO_CTRL_DGRAM_SCTP_GET_RCVINFO, sizeof(rdata->recordinfo), &rdata->recordinfo);
 239         }
 240 #endif
 241
 242         s->packet = NULL;
 243         s->packet_length = 0;
 244         memset(&(s->s3->rbuf), 0, sizeof(SSL3_BUFFER));
 245         memset(&(s->s3->rrec), 0, sizeof(SSL3_RECORD));
 246
 247         if (!ssl3_setup_buffers(s))
 248                 {
 249                 SSLerr(SSL_F_DTLS1_BUFFER_RECORD, ERR_R_INTERNAL_ERROR);
 250                 if (rdata->rbuf.buf != NULL)
 251                         OPENSSL_free(rdata->rbuf.buf);
 252                 OPENSSL_free(rdata);
 253                 pitem_free(item);
 254                 return(-1);
 255                 }
 256
 257         /* insert should not fail, since duplicates are dropped */
 258         if (pqueue_insert(queue->q, item) == NULL)
 259                 {
 260                 SSLerr(SSL_F_DTLS1_BUFFER_RECORD, ERR_R_INTERNAL_ERROR);
 261                 if (rdata->rbuf.buf != NULL)
 262                         OPENSSL_free(rdata->rbuf.buf);
 263                 OPENSSL_free(rdata);
 264                 pitem_free(item);
 265                 return(-1);
 266                 }
 267
 268         return(1);
 269         }
 270
 271
 272 static int
 273 dtls1_retrieve_buffered_record(SSL *s, record_pqueue *queue)
 274     {
 275     pitem *item;
 276
 277     item = pqueue_pop(queue->q);
 278     if (item)
 279         {
 280         dtls1_copy_record(s, item);
 281
 282         OPENSSL_free(item->data);
 283                 pitem_free(item);
 284
 285         return(1);
 286         }
 287
 288     return(0);
 289     }
 290
 291
 292 /* retrieve a buffered record that belongs to the new epoch, i.e., not processed
 293  * yet */
 294 #define dtls1_get_unprocessed_record(s) \
 295                    dtls1_retrieve_buffered_record((s), \
 296                    &((s)->d1->unprocessed_rcds))
 297
 298 /* retrieve a buffered record that belongs to the current epoch, ie, processed */
 299 #define dtls1_get_processed_record(s) \
 300                    dtls1_retrieve_buffered_record((s), \
 301                    &((s)->d1->processed_rcds))
 302
 303 static int
 304 dtls1_process_buffered_records(SSL *s)
 305     {
 306     pitem *item;
 307
 308     item = pqueue_peek(s->d1->unprocessed_rcds.q);
 309     if (item)
 310         {
 311         /* Check if epoch is current. */
 312         if (s->d1->unprocessed_rcds.epoch != s->d1->r_epoch)
 313             return(1);  /* Nothing to do. */
 314
 315         /* Process all the records. */
 316         while (pqueue_peek(s->d1->unprocessed_rcds.q))
 317             {
 318             dtls1_get_unprocessed_record(s);
 319             if ( ! dtls1_process_record(s))
 320                 return(0);
 321             if(dtls1_buffer_record(s, &(s->d1->processed_rcds),
 322                 s->s3->rrec.seq_num)<0)
 323                 return -1;
 324             }
 325         }
 326
 327     /* sync epoch numbers once all the unprocessed records
 328      * have been processed */
 329     s->d1->processed_rcds.epoch = s->d1->r_epoch;
 330     s->d1->unprocessed_rcds.epoch = s->d1->r_epoch + 1;
 331
 332     return(1);
 333     }
 334
 335
 336 #if 0
 337
 338 static int
 339 dtls1_get_buffered_record(SSL *s)
 340         {
 341         pitem *item;
 342         PQ_64BIT priority =
 343                 (((PQ_64BIT)s->d1->handshake_read_seq) << 32) |
 344                 ((PQ_64BIT)s->d1->r_msg_hdr.frag_off);
 345
 346         if ( ! SSL_in_init(s))  /* if we're not (re)negotiating,
 347                                                            nothing buffered */
 348                 return 0;
 349
 350
 351         item = pqueue_peek(s->d1->rcvd_records);
 352         if (item && item->priority == priority)
 353                 {
 354                 /* Check if we've received the record of interest.  It must be
 355                  * a handshake record, since data records as passed up without
 356                  * buffering */
 357                 DTLS1_RECORD_DATA *rdata;
 358                 item = pqueue_pop(s->d1->rcvd_records);
 359                 rdata = (DTLS1_RECORD_DATA *)item->data;
 360
 361                 if (s->s3->rbuf.buf != NULL)
 362                         OPENSSL_free(s->s3->rbuf.buf);
 363
 364                 s->packet = rdata->packet;
 365                 s->packet_length = rdata->packet_length;
 366                 memcpy(&(s->s3->rbuf), &(rdata->rbuf), sizeof(SSL3_BUFFER));
 367                 memcpy(&(s->s3->rrec), &(rdata->rrec), sizeof(SSL3_RECORD));
 368
 369                 OPENSSL_free(item->data);
 370                 pitem_free(item);
 371
 372                 /* s->d1->next_expected_seq_num++; */
 373                 return(1);
 374                 }
 375
 376         return 0;
 377         }
 378
 379 #endif
 380
 381 static int
 382 dtls1_process_record(SSL *s)
 383 {
 384         int i,al;
 385         int enc_err;
 386         SSL_SESSION *sess;
 387         SSL3_RECORD *rr;
 388         unsigned int mac_size, orig_len;
 389         unsigned char md[EVP_MAX_MD_SIZE];
 390
 391         rr= &(s->s3->rrec);
 392         sess = s->session;
 393
 394         /* At this point, s->packet_length == SSL3_RT_HEADER_LNGTH + rr->length,
 395          * and we have that many bytes in s->packet
 396          */
 397         rr->input= &(s->packet[DTLS1_RT_HEADER_LENGTH]);
 398
 399         /* ok, we can now read from 's->packet' data into 'rr'
 400          * rr->input points at rr->length bytes, which
 401          * need to be copied into rr->data by either
 402          * the decryption or by the decompression
 403          * When the data is 'copied' into the rr->data buffer,
 404          * rr->input will be pointed at the new buffer */
 405
 406         /* We now have - encrypted [ MAC [ compressed [ plain ] ] ]
 407          * rr->length bytes of encrypted compressed stuff. */
 408
 409         /* check is not needed I believe */
 410         if (rr->length > SSL3_RT_MAX_ENCRYPTED_LENGTH)
 411                 {
 412                 al=SSL_AD_RECORD_OVERFLOW;
 413                 SSLerr(SSL_F_DTLS1_PROCESS_RECORD,SSL_R_ENCRYPTED_LENGTH_TOO_LONG);
 414                 goto f_err;
 415                 }
 416
 417         /* decrypt in place in 'rr->input' */
 418         rr->data=rr->input;
 419
 420         enc_err = s->method->ssl3_enc->enc(s,0);
 421         /*-
 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                         dtls1_record_bitmap_update(s, bitmap);/* Mark receipt of record. */
 718                         }
 719                 rr->length = 0;
 720                 s->packet_length = 0;
 721                 goto again;
 722                 }
 723
 724         if (!dtls1_process_record(s))
 725                 {
 726                 rr->length = 0;
 727                 s->packet_length = 0;  /* dump this record */
 728                 goto again;   /* get another record */
 729                 }
 730         dtls1_record_bitmap_update(s, bitmap);/* Mark receipt of record. */
 731
 732         return(1);
 733
 734         }
 735
 736 /*-
 737  * Return up to 'len' payload bytes received in 'type' records.
 738  * 'type' is one of the following:
 739  *
 740  *   -  SSL3_RT_HANDSHAKE (when ssl3_get_message calls us)
 741  *   -  SSL3_RT_APPLICATION_DATA (when ssl3_read calls us)
 742  *   -  0 (during a shutdown, no data has to be returned)
 743  *
 744  * If we don't have stored data to work from, read a SSL/TLS record first
 745  * (possibly multiple records if we still don't have anything to return).
 746  *
 747  * This function must handle any surprises the peer may have for us, such as
 748  * Alert records (e.g. close_notify), ChangeCipherSpec records (not really
 749  * a surprise, but handled as if it were), or renegotiation requests.
 750  * Also if record payloads contain fragments too small to process, we store
 751  * them until there is enough for the respective protocol (the record protocol
 752  * may use arbitrary fragmentation and even interleaving):
 753  *     Change cipher spec protocol
 754  *             just 1 byte needed, no need for keeping anything stored
 755  *     Alert protocol
 756  *             2 bytes needed (AlertLevel, AlertDescription)
 757  *     Handshake protocol
 758  *             4 bytes needed (HandshakeType, uint24 length) -- we just have
 759  *             to detect unexpected Client Hello and Hello Request messages
 760  *             here, anything else is handled by higher layers
 761  *     Application data protocol
 762  *             none of our business
 763  */
 764 int dtls1_read_bytes(SSL *s, int type, unsigned char *buf, int len, int peek)
 765         {
 766         int al,i,j,ret;
 767         unsigned int n;
 768         SSL3_RECORD *rr;
 769         void (*cb)(const SSL *ssl,int type2,int val)=NULL;
 770
 771         if (s->s3->rbuf.buf == NULL) /* Not initialized yet */
 772                 if (!ssl3_setup_buffers(s))
 773                         return(-1);
 774
 775     /* XXX: check what the second '&& type' is about */
 776         if ((type && (type != SSL3_RT_APPLICATION_DATA) &&
 777                 (type != SSL3_RT_HANDSHAKE) && type) ||
 778             (peek && (type != SSL3_RT_APPLICATION_DATA)))
 779                 {
 780                 SSLerr(SSL_F_DTLS1_READ_BYTES, ERR_R_INTERNAL_ERROR);
 781                 return -1;
 782                 }
 783
 784         /* check whether there's a handshake message (client hello?) waiting */
 785         if ( (ret = have_handshake_fragment(s, type, buf, len, peek)))
 786                 return ret;
 787
 788         /* Now s->d1->handshake_fragment_len == 0 if type == SSL3_RT_HANDSHAKE. */
 789
 790 #ifndef OPENSSL_NO_SCTP
 791         /* Continue handshake if it had to be interrupted to read
 792          * app data with SCTP.
 793          */
 794         if ((!s->in_handshake && SSL_in_init(s)) ||
 795             (BIO_dgram_is_sctp(SSL_get_rbio(s)) &&
 796              (s->state == DTLS1_SCTP_ST_SR_READ_SOCK || s->state == DTLS1_SCTP_ST_CR_READ_SOCK) &&
 797              s->s3->in_read_app_data != 2))
 798 #else
 799         if (!s->in_handshake && SSL_in_init(s))
 800 #endif
 801                 {
 802                 /* type == SSL3_RT_APPLICATION_DATA */
 803                 i=s->handshake_func(s);
 804                 if (i < 0) return(i);
 805                 if (i == 0)
 806                         {
 807                         SSLerr(SSL_F_DTLS1_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
 808                         return(-1);
 809                         }
 810                 }
 811
 812 start:
 813         s->rwstate=SSL_NOTHING;
 814
 815         /*-
 816          * s->s3->rrec.type         - is the type of record
 817          * s->s3->rrec.data,    - data
 818          * s->s3->rrec.off,     - offset into 'data' for next read
 819          * s->s3->rrec.length,  - number of bytes.
 820          */
 821         rr = &(s->s3->rrec);
 822
 823         /* We are not handshaking and have no data yet,
 824          * so process data buffered during the last handshake
 825          * in advance, if any.
 826          */
 827         if (s->state == SSL_ST_OK && rr->length == 0)
 828                 {
 829                 pitem *item;
 830                 item = pqueue_pop(s->d1->buffered_app_data.q);
 831                 if (item)
 832                         {
 833 #ifndef OPENSSL_NO_SCTP
 834                         /* Restore bio_dgram_sctp_rcvinfo struct */
 835                         if (BIO_dgram_is_sctp(SSL_get_rbio(s)))
 836                                 {
 837                                 DTLS1_RECORD_DATA *rdata = (DTLS1_RECORD_DATA *) item->data;
 838                                 BIO_ctrl(SSL_get_rbio(s), BIO_CTRL_DGRAM_SCTP_SET_RCVINFO, sizeof(rdata->recordinfo), &rdata->recordinfo);
 839                                 }
 840 #endif
 841
 842                         dtls1_copy_record(s, item);
 843
 844                         OPENSSL_free(item->data);
 845                         pitem_free(item);
 846                         }
 847                 }
 848
 849         /* Check for timeout */
 850         if (dtls1_handle_timeout(s) > 0)
 851                 goto start;
 852
 853         /* get new packet if necessary */
 854         if ((rr->length == 0) || (s->rstate == SSL_ST_READ_BODY))
 855                 {
 856                 ret=dtls1_get_record(s);
 857                 if (ret <= 0)
 858                         {
 859                         ret = dtls1_read_failed(s, ret);
 860                         /* anything other than a timeout is an error */
 861                         if (ret <= 0)
 862                                 return(ret);
 863                         else
 864                                 goto start;
 865                         }
 866                 }
 867
 868         if (s->d1->listen && rr->type != SSL3_RT_HANDSHAKE)
 869                 {
 870                 rr->length = 0;
 871                 goto start;
 872                 }
 873
 874         /* we now have a packet which can be read and processed */
 875
 876         if (s->s3->change_cipher_spec /* set when we receive ChangeCipherSpec,
 877                                        * reset by ssl3_get_finished */
 878                 && (rr->type != SSL3_RT_HANDSHAKE))
 879                 {
 880                 /* We now have application data between CCS and Finished.
 881                  * Most likely the packets were reordered on their way, so
 882                  * buffer the application data for later processing rather
 883                  * than dropping the connection.
 884                  */
 885                 if(dtls1_buffer_record(s, &(s->d1->buffered_app_data), rr->seq_num)<0)
 886                         {
 887                         SSLerr(SSL_F_DTLS1_READ_BYTES, ERR_R_INTERNAL_ERROR);
 888                         return -1;
 889                         }
 890                 rr->length = 0;
 891                 goto start;
 892                 }
 893
 894         /* If the other end has shut down, throw anything we read away
 895          * (even in 'peek' mode) */
 896         if (s->shutdown & SSL_RECEIVED_SHUTDOWN)
 897                 {
 898                 rr->length=0;
 899                 s->rwstate=SSL_NOTHING;
 900                 return(0);
 901                 }
 902
 903
 904         if (type == rr->type) /* SSL3_RT_APPLICATION_DATA or SSL3_RT_HANDSHAKE */
 905                 {
 906                 /* make sure that we are not getting application data when we
 907                  * are doing a handshake for the first time */
 908                 if (SSL_in_init(s) && (type == SSL3_RT_APPLICATION_DATA) &&
 909                         (s->enc_read_ctx == NULL))
 910                         {
 911                         al=SSL_AD_UNEXPECTED_MESSAGE;
 912                         SSLerr(SSL_F_DTLS1_READ_BYTES,SSL_R_APP_DATA_IN_HANDSHAKE);
 913                         goto f_err;
 914                         }
 915
 916                 if (len <= 0) return(len);
 917
 918                 if ((unsigned int)len > rr->length)
 919                         n = rr->length;
 920                 else
 921                         n = (unsigned int)len;
 922
 923                 memcpy(buf,&(rr->data[rr->off]),n);
 924                 if (!peek)
 925                         {
 926                         rr->length-=n;
 927                         rr->off+=n;
 928                         if (rr->length == 0)
 929                                 {
 930                                 s->rstate=SSL_ST_READ_HEADER;
 931                                 rr->off=0;
 932                                 }
 933                         }
 934
 935 #ifndef OPENSSL_NO_SCTP
 936                         /* We were about to renegotiate but had to read
 937                          * belated application data first, so retry.
 938                          */
 939                         if (BIO_dgram_is_sctp(SSL_get_rbio(s)) &&
 940                             rr->type == SSL3_RT_APPLICATION_DATA &&
 941                             (s->state == DTLS1_SCTP_ST_SR_READ_SOCK || s->state == DTLS1_SCTP_ST_CR_READ_SOCK))
 942                                 {
 943                                 s->rwstate=SSL_READING;
 944                                 BIO_clear_retry_flags(SSL_get_rbio(s));
 945                                 BIO_set_retry_read(SSL_get_rbio(s));
 946                                 }
 947
 948                         /* We might had to delay a close_notify alert because
 949                          * of reordered app data. If there was an alert and there
 950                          * is no message to read anymore, finally set shutdown.
 951                          */
 952                         if (BIO_dgram_is_sctp(SSL_get_rbio(s)) &&
 953                             s->d1->shutdown_received && !BIO_dgram_sctp_msg_waiting(SSL_get_rbio(s)))
 954                                 {
 955                                 s->shutdown |= SSL_RECEIVED_SHUTDOWN;
 956                                 return(0);
 957                                 }
 958 #endif
 959                 return(n);
 960                 }
 961
 962
 963         /* If we get here, then type != rr->type; if we have a handshake
 964          * message, then it was unexpected (Hello Request or Client Hello). */
 965
 966         /* In case of record types for which we have 'fragment' storage,
 967          * fill that so that we can process the data at a fixed place.
 968          */
 969                 {
 970                 unsigned int k, dest_maxlen = 0;
 971                 unsigned char *dest = NULL;
 972                 unsigned int *dest_len = NULL;
 973
 974                 if (rr->type == SSL3_RT_HANDSHAKE)
 975                         {
 976                         dest_maxlen = sizeof s->d1->handshake_fragment;
 977                         dest = s->d1->handshake_fragment;
 978                         dest_len = &s->d1->handshake_fragment_len;
 979                         }
 980                 else if (rr->type == SSL3_RT_ALERT)
 981                         {
 982                         dest_maxlen = sizeof(s->d1->alert_fragment);
 983                         dest = s->d1->alert_fragment;
 984                         dest_len = &s->d1->alert_fragment_len;
 985                         }
 986 #ifndef OPENSSL_NO_HEARTBEATS
 987                 else if (rr->type == TLS1_RT_HEARTBEAT)
 988                         {
 989                         dtls1_process_heartbeat(s);
 990
 991                         /* Exit and notify application to read again */
 992                         rr->length = 0;
 993                         s->rwstate=SSL_READING;
 994                         BIO_clear_retry_flags(SSL_get_rbio(s));
 995                         BIO_set_retry_read(SSL_get_rbio(s));
 996                         return(-1);
 997                         }
 998 #endif
 999                 /* else it's a CCS message, or application data or wrong */
1000                 else if (rr->type != SSL3_RT_CHANGE_CIPHER_SPEC)
1001                         {
1002                         /* Application data while renegotiating
1003                          * is allowed. Try again reading.
1004                          */
1005                         if (rr->type == SSL3_RT_APPLICATION_DATA)
1006                                 {
1007                                 BIO *bio;
1008                                 s->s3->in_read_app_data=2;
1009                                 bio=SSL_get_rbio(s);
1010                                 s->rwstate=SSL_READING;
1011                                 BIO_clear_retry_flags(bio);
1012                                 BIO_set_retry_read(bio);
1013                                 return(-1);
1014                                 }
1015
1016                         /* Not certain if this is the right error handling */
1017                         al=SSL_AD_UNEXPECTED_MESSAGE;
1018                         SSLerr(SSL_F_DTLS1_READ_BYTES,SSL_R_UNEXPECTED_RECORD);
1019                         goto f_err;
1020                         }
1021
1022                 if (dest_maxlen > 0)
1023                         {
1024             /* XDTLS:  In a pathalogical case, the Client Hello
1025              *  may be fragmented--don't always expect dest_maxlen bytes */
1026                         if ( rr->length < dest_maxlen)
1027                                 {
1028 #ifdef DTLS1_AD_MISSING_HANDSHAKE_MESSAGE
1029                                 /*
1030                                  * for normal alerts rr->length is 2, while
1031                                  * dest_maxlen is 7 if we were to handle this
1032                                  * non-existing alert...
1033                                  */
1034                                 FIX ME
1035 #endif
1036                                 s->rstate=SSL_ST_READ_HEADER;
1037                                 rr->length = 0;
1038                                 goto start;
1039                                 }
1040
1041                         /* now move 'n' bytes: */
1042                         for ( k = 0; k < dest_maxlen; k++)
1043                                 {
1044                                 dest[k] = rr->data[rr->off++];
1045                                 rr->length--;
1046                                 }
1047                         *dest_len = dest_maxlen;
1048                         }
1049                 }
1050
1051         /*-
1052          * s->d1->handshake_fragment_len == 12  iff  rr->type == SSL3_RT_HANDSHAKE;
1053          * s->d1->alert_fragment_len == 7      iff  rr->type == SSL3_RT_ALERT.
1054          * (Possibly rr is 'empty' now, i.e. rr->length may be 0.)
1055          */
1056
1057         /* If we are a client, check for an incoming 'Hello Request': */
1058         if ((!s->server) &&
1059                 (s->d1->handshake_fragment_len >= DTLS1_HM_HEADER_LENGTH) &&
1060                 (s->d1->handshake_fragment[0] == SSL3_MT_HELLO_REQUEST) &&
1061                 (s->session != NULL) && (s->session->cipher != NULL))
1062                 {
1063                 s->d1->handshake_fragment_len = 0;
1064
1065                 if ((s->d1->handshake_fragment[1] != 0) ||
1066                         (s->d1->handshake_fragment[2] != 0) ||
1067                         (s->d1->handshake_fragment[3] != 0))
1068                         {
1069                         al=SSL_AD_DECODE_ERROR;
1070                         SSLerr(SSL_F_DTLS1_READ_BYTES,SSL_R_BAD_HELLO_REQUEST);
1071                         goto err;
1072                         }
1073
1074                 /* no need to check sequence number on HELLO REQUEST messages */
1075
1076                 if (s->msg_callback)
1077                         s->msg_callback(0, s->version, SSL3_RT_HANDSHAKE,
1078                                 s->d1->handshake_fragment, 4, s, s->msg_callback_arg);
1079
1080                 if (SSL_is_init_finished(s) &&
1081                         !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS) &&
1082                         !s->s3->renegotiate)
1083                         {
1084                         s->d1->handshake_read_seq++;
1085                         s->new_session = 1;
1086                         ssl3_renegotiate(s);
1087                         if (ssl3_renegotiate_check(s))
1088                                 {
1089                                 i=s->handshake_func(s);
1090                                 if (i < 0) return(i);
1091                                 if (i == 0)
1092                                         {
1093                                         SSLerr(SSL_F_DTLS1_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
1094                                         return(-1);
1095                                         }
1096
1097                                 if (!(s->mode & SSL_MODE_AUTO_RETRY))
1098                                         {
1099                                         if (s->s3->rbuf.left == 0) /* no read-ahead left? */
1100                                                 {
1101                                                 BIO *bio;
1102                                                 /* In the case where we try to read application data,
1103                                                  * but we trigger an SSL handshake, we return -1 with
1104                                                  * the retry option set.  Otherwise renegotiation may
1105                                                  * cause nasty problems in the blocking world */
1106                                                 s->rwstate=SSL_READING;
1107                                                 bio=SSL_get_rbio(s);
1108                                                 BIO_clear_retry_flags(bio);
1109                                                 BIO_set_retry_read(bio);
1110                                                 return(-1);
1111                                                 }
1112                                         }
1113                                 }
1114                         }
1115                 /* we either finished a handshake or ignored the request,
1116                  * now try again to obtain the (application) data we were asked for */
1117                 goto start;
1118                 }
1119
1120         if (s->d1->alert_fragment_len >= DTLS1_AL_HEADER_LENGTH)
1121                 {
1122                 int alert_level = s->d1->alert_fragment[0];
1123                 int alert_descr = s->d1->alert_fragment[1];
1124
1125                 s->d1->alert_fragment_len = 0;
1126
1127                 if (s->msg_callback)
1128                         s->msg_callback(0, s->version, SSL3_RT_ALERT,
1129                                 s->d1->alert_fragment, 2, s, s->msg_callback_arg);
1130
1131                 if (s->info_callback != NULL)
1132                         cb=s->info_callback;
1133                 else if (s->ctx->info_callback != NULL)
1134                         cb=s->ctx->info_callback;
1135
1136                 if (cb != NULL)
1137                         {
1138                         j = (alert_level << 8) | alert_descr;
1139                         cb(s, SSL_CB_READ_ALERT, j);
1140                         }
1141
1142                 if (alert_level == 1) /* warning */
1143                         {
1144                         s->s3->warn_alert = alert_descr;
1145                         if (alert_descr == SSL_AD_CLOSE_NOTIFY)
1146                                 {
1147 #ifndef OPENSSL_NO_SCTP
1148                                 /* With SCTP and streams the socket may deliver app data
1149                                  * after a close_notify alert. We have to check this
1150                                  * first so that nothing gets discarded.
1151                                  */
1152                                 if (BIO_dgram_is_sctp(SSL_get_rbio(s)) &&
1153                                         BIO_dgram_sctp_msg_waiting(SSL_get_rbio(s)))
1154                                         {
1155                                         s->d1->shutdown_received = 1;
1156                                         s->rwstate=SSL_READING;
1157                                         BIO_clear_retry_flags(SSL_get_rbio(s));
1158                                         BIO_set_retry_read(SSL_get_rbio(s));
1159                                         return -1;
1160                                         }
1161 #endif
1162                                 s->shutdown |= SSL_RECEIVED_SHUTDOWN;
1163                                 return(0);
1164                                 }
1165 #if 0
1166             /* XXX: this is a possible improvement in the future */
1167                         /* now check if it's a missing record */
1168                         if (alert_descr == DTLS1_AD_MISSING_HANDSHAKE_MESSAGE)
1169                                 {
1170                                 unsigned short seq;
1171                                 unsigned int frag_off;
1172                                 unsigned char *p = &(s->d1->alert_fragment[2]);
1173
1174                                 n2s(p, seq);
1175                                 n2l3(p, frag_off);
1176
1177                                 dtls1_retransmit_message(s,
1178                                                                                  dtls1_get_queue_priority(frag->msg_header.seq, 0),
1179                                                                                  frag_off, &found);
1180                                 if ( ! found  && SSL_in_init(s))
1181                                         {
1182                                         /* fprintf( stderr,"in init = %d\n", SSL_in_init(s)); */
1183                                         /* requested a message not yet sent,
1184                                            send an alert ourselves */
1185                                         ssl3_send_alert(s,SSL3_AL_WARNING,
1186                                                 DTLS1_AD_MISSING_HANDSHAKE_MESSAGE);
1187                                         }
1188                                 }
1189 #endif
1190                         }
1191                 else if (alert_level == 2) /* fatal */
1192                         {
1193                         char tmp[16];
1194
1195                         s->rwstate=SSL_NOTHING;
1196                         s->s3->fatal_alert = alert_descr;
1197                         SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_AD_REASON_OFFSET + alert_descr);
1198                         BIO_snprintf(tmp,sizeof tmp,"%d",alert_descr);
1199                         ERR_add_error_data(2,"SSL alert number ",tmp);
1200                         s->shutdown|=SSL_RECEIVED_SHUTDOWN;
1201                         SSL_CTX_remove_session(s->ctx,s->session);
1202                         return(0);
1203                         }
1204                 else
1205                         {
1206                         al=SSL_AD_ILLEGAL_PARAMETER;
1207                         SSLerr(SSL_F_DTLS1_READ_BYTES,SSL_R_UNKNOWN_ALERT_TYPE);
1208                         goto f_err;
1209                         }
1210
1211                 goto start;
1212                 }
1213
1214         if (s->shutdown & SSL_SENT_SHUTDOWN) /* but we have not received a shutdown */
1215                 {
1216                 s->rwstate=SSL_NOTHING;
1217                 rr->length=0;
1218                 return(0);
1219                 }
1220
1221         if (rr->type == SSL3_RT_CHANGE_CIPHER_SPEC)
1222                 {
1223                 struct ccs_header_st ccs_hdr;
1224                 unsigned int ccs_hdr_len = DTLS1_CCS_HEADER_LENGTH;
1225
1226                 dtls1_get_ccs_header(rr->data, &ccs_hdr);
1227
1228                 if (s->version == DTLS1_BAD_VER)
1229                         ccs_hdr_len = 3;
1230
1231                 /* 'Change Cipher Spec' is just a single byte, so we know
1232                  * exactly what the record payload has to look like */
1233                 /* XDTLS: check that epoch is consistent */
1234                 if (    (rr->length != ccs_hdr_len) ||
1235                         (rr->off != 0) || (rr->data[0] != SSL3_MT_CCS))
1236                         {
1237                         i=SSL_AD_ILLEGAL_PARAMETER;
1238                         SSLerr(SSL_F_DTLS1_READ_BYTES,SSL_R_BAD_CHANGE_CIPHER_SPEC);
1239                         goto err;
1240                         }
1241
1242                 rr->length=0;
1243
1244                 if (s->msg_callback)
1245                         s->msg_callback(0, s->version, SSL3_RT_CHANGE_CIPHER_SPEC,
1246                                 rr->data, 1, s, s->msg_callback_arg);
1247
1248                 /* We can't process a CCS now, because previous handshake
1249                  * messages are still missing, so just drop it.
1250                  */
1251                 if (!s->d1->change_cipher_spec_ok)
1252                         {
1253                         goto start;
1254                         }
1255
1256                 s->d1->change_cipher_spec_ok = 0;
1257
1258                 s->s3->change_cipher_spec=1;
1259                 if (!ssl3_do_change_cipher_spec(s))
1260                         goto err;
1261
1262                 /* do this whenever CCS is processed */
1263                 dtls1_reset_seq_numbers(s, SSL3_CC_READ);
1264
1265                 if (s->version == DTLS1_BAD_VER)
1266                         s->d1->handshake_read_seq++;
1267
1268 #ifndef OPENSSL_NO_SCTP
1269                 /* Remember that a CCS has been received,
1270                  * so that an old key of SCTP-Auth can be
1271                  * deleted when a CCS is sent. Will be ignored
1272                  * if no SCTP is used
1273                  */
1274                 BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_AUTH_CCS_RCVD, 1, NULL);
1275 #endif
1276
1277                 goto start;
1278                 }
1279
1280         /* Unexpected handshake message (Client Hello, or protocol violation) */
1281         if ((s->d1->handshake_fragment_len >= DTLS1_HM_HEADER_LENGTH) &&
1282                 !s->in_handshake)
1283                 {
1284                 struct hm_header_st msg_hdr;
1285
1286                 /* this may just be a stale retransmit */
1287                 dtls1_get_message_header(rr->data, &msg_hdr);
1288                 if( rr->epoch != s->d1->r_epoch)
1289                         {
1290                         rr->length = 0;
1291                         goto start;
1292                         }
1293
1294                 /* If we are server, we may have a repeated FINISHED of the
1295                  * client here, then retransmit our CCS and FINISHED.
1296                  */
1297                 if (msg_hdr.type == SSL3_MT_FINISHED)
1298                         {
1299                         if (dtls1_check_timeout_num(s) < 0)
1300                                 return -1;
1301
1302                         dtls1_retransmit_buffered_messages(s);
1303                         rr->length = 0;
1304                         goto start;
1305                         }
1306
1307                 if (((s->state&SSL_ST_MASK) == SSL_ST_OK) &&
1308                         !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS))
1309                         {
1310 #if 0 /* worked only because C operator preferences are not as expected (and
1311        * because this is not really needed for clients except for detecting
1312        * protocol violations): */
1313                         s->state=SSL_ST_BEFORE|(s->server)
1314                                 ?SSL_ST_ACCEPT
1315                                 :SSL_ST_CONNECT;
1316 #else
1317                         s->state = s->server ? SSL_ST_ACCEPT : SSL_ST_CONNECT;
1318 #endif
1319                         s->renegotiate=1;
1320                         s->new_session=1;
1321                         }
1322                 i=s->handshake_func(s);
1323                 if (i < 0) return(i);
1324                 if (i == 0)
1325                         {
1326                         SSLerr(SSL_F_DTLS1_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
1327                         return(-1);
1328                         }
1329
1330                 if (!(s->mode & SSL_MODE_AUTO_RETRY))
1331                         {
1332                         if (s->s3->rbuf.left == 0) /* no read-ahead left? */
1333                                 {
1334                                 BIO *bio;
1335                                 /* In the case where we try to read application data,
1336                                  * but we trigger an SSL handshake, we return -1 with
1337                                  * the retry option set.  Otherwise renegotiation may
1338                                  * cause nasty problems in the blocking world */
1339                                 s->rwstate=SSL_READING;
1340                                 bio=SSL_get_rbio(s);
1341                                 BIO_clear_retry_flags(bio);
1342                                 BIO_set_retry_read(bio);
1343                                 return(-1);
1344                                 }
1345                         }
1346                 goto start;
1347                 }
1348
1349         switch (rr->type)
1350                 {
1351         default:
1352 #ifndef OPENSSL_NO_TLS
1353                 /* TLS just ignores unknown message types */
1354                 if (s->version == TLS1_VERSION)
1355                         {
1356                         rr->length = 0;
1357                         goto start;
1358                         }
1359 #endif
1360                 al=SSL_AD_UNEXPECTED_MESSAGE;
1361                 SSLerr(SSL_F_DTLS1_READ_BYTES,SSL_R_UNEXPECTED_RECORD);
1362                 goto f_err;
1363         case SSL3_RT_CHANGE_CIPHER_SPEC:
1364         case SSL3_RT_ALERT:
1365         case SSL3_RT_HANDSHAKE:
1366                 /* we already handled all of these, with the possible exception
1367                  * of SSL3_RT_HANDSHAKE when s->in_handshake is set, but that
1368                  * should not happen when type != rr->type */
1369                 al=SSL_AD_UNEXPECTED_MESSAGE;
1370                 SSLerr(SSL_F_DTLS1_READ_BYTES,ERR_R_INTERNAL_ERROR);
1371                 goto f_err;
1372         case SSL3_RT_APPLICATION_DATA:
1373                 /* At this point, we were expecting handshake data,
1374                  * but have application data.  If the library was
1375                  * running inside ssl3_read() (i.e. in_read_app_data
1376                  * is set) and it makes sense to read application data
1377                  * at this point (session renegotiation not yet started),
1378                  * we will indulge it.
1379                  */
1380                 if (s->s3->in_read_app_data &&
1381                         (s->s3->total_renegotiations != 0) &&
1382                         ((
1383                                 (s->state & SSL_ST_CONNECT) &&
1384                                 (s->state >= SSL3_ST_CW_CLNT_HELLO_A) &&
1385                                 (s->state <= SSL3_ST_CR_SRVR_HELLO_A)
1386                                 ) || (
1387                                         (s->state & SSL_ST_ACCEPT) &&
1388                                         (s->state <= SSL3_ST_SW_HELLO_REQ_A) &&
1389                                         (s->state >= SSL3_ST_SR_CLNT_HELLO_A)
1390                                         )
1391                                 ))
1392                         {
1393                         s->s3->in_read_app_data=2;
1394                         return(-1);
1395                         }
1396                 else
1397                         {
1398                         al=SSL_AD_UNEXPECTED_MESSAGE;
1399                         SSLerr(SSL_F_DTLS1_READ_BYTES,SSL_R_UNEXPECTED_RECORD);
1400                         goto f_err;
1401                         }
1402                 }
1403         /* not reached */
1404
1405 f_err:
1406         ssl3_send_alert(s,SSL3_AL_FATAL,al);
1407 err:
1408         return(-1);
1409         }
1410
1411 int
1412 dtls1_write_app_data_bytes(SSL *s, int type, const void *buf_, int len)
1413         {
1414         int i;
1415
1416 #ifndef OPENSSL_NO_SCTP
1417                 /* Check if we have to continue an interrupted handshake
1418                  * for reading belated app data with SCTP.
1419                  */
1420                 if ((SSL_in_init(s) && !s->in_handshake) ||
1421                     (BIO_dgram_is_sctp(SSL_get_wbio(s)) &&
1422                      (s->state == DTLS1_SCTP_ST_SR_READ_SOCK || s->state == DTLS1_SCTP_ST_CR_READ_SOCK)))
1423 #else
1424                 if (SSL_in_init(s) && !s->in_handshake)
1425 #endif
1426                 {
1427                 i=s->handshake_func(s);
1428                 if (i < 0) return(i);
1429                 if (i == 0)
1430                         {
1431                         SSLerr(SSL_F_DTLS1_WRITE_APP_DATA_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
1432                         return -1;
1433                         }
1434                 }
1435
1436         if (len > SSL3_RT_MAX_PLAIN_LENGTH)
1437                 {
1438                         SSLerr(SSL_F_DTLS1_WRITE_APP_DATA_BYTES,SSL_R_DTLS_MESSAGE_TOO_BIG);
1439                         return -1;
1440                 }
1441
1442         i = dtls1_write_bytes(s, type, buf_, len);
1443         return i;
1444         }
1445
1446
1447         /* this only happens when a client hello is received and a handshake
1448          * is started. */
1449 static int
1450 have_handshake_fragment(SSL *s, int type, unsigned char *buf,
1451         int len, int peek)
1452         {
1453
1454         if ((type == SSL3_RT_HANDSHAKE) && (s->d1->handshake_fragment_len > 0))
1455                 /* (partially) satisfy request from storage */
1456                 {
1457                 unsigned char *src = s->d1->handshake_fragment;
1458                 unsigned char *dst = buf;
1459                 unsigned int k,n;
1460
1461                 /* peek == 0 */
1462                 n = 0;
1463                 while ((len > 0) && (s->d1->handshake_fragment_len > 0))
1464                         {
1465                         *dst++ = *src++;
1466                         len--; s->d1->handshake_fragment_len--;
1467                         n++;
1468                         }
1469                 /* move any remaining fragment bytes: */
1470                 for (k = 0; k < s->d1->handshake_fragment_len; k++)
1471                         s->d1->handshake_fragment[k] = *src++;
1472                 return n;
1473                 }
1474
1475         return 0;
1476         }
1477
1478
1479
1480
1481 /* Call this to write data in records of type 'type'
1482  * It will return <= 0 if not all data has been sent or non-blocking IO.
1483  */
1484 int dtls1_write_bytes(SSL *s, int type, const void *buf, int len)
1485         {
1486         int i;
1487
1488         OPENSSL_assert(len <= SSL3_RT_MAX_PLAIN_LENGTH);
1489         s->rwstate=SSL_NOTHING;
1490         i=do_dtls1_write(s, type, buf, len, 0);
1491         return i;
1492         }
1493
1494 int do_dtls1_write(SSL *s, int type, const unsigned char *buf, unsigned int len, int create_empty_fragment)
1495         {
1496         unsigned char *p,*pseq;
1497         int i,mac_size,clear=0;
1498         int prefix_len = 0;
1499         int eivlen;
1500         SSL3_RECORD *wr;
1501         SSL3_BUFFER *wb;
1502         SSL_SESSION *sess;
1503
1504         /* first check if there is a SSL3_BUFFER still being written
1505          * out.  This will happen with non blocking IO */
1506         if (s->s3->wbuf.left != 0)
1507                 {
1508                 OPENSSL_assert(0); /* XDTLS:  want to see if we ever get here */
1509                 return(ssl3_write_pending(s,type,buf,len));
1510                 }
1511
1512         /* If we have an alert to send, lets send it */
1513         if (s->s3->alert_dispatch)
1514                 {
1515                 i=s->method->ssl_dispatch_alert(s);
1516                 if (i <= 0)
1517                         return(i);
1518                 /* if it went, fall through and send more stuff */
1519                 }
1520
1521         if (len == 0 && !create_empty_fragment)
1522                 return 0;
1523
1524         wr= &(s->s3->wrec);
1525         wb= &(s->s3->wbuf);
1526         sess=s->session;
1527
1528         if (    (sess == NULL) ||
1529                 (s->enc_write_ctx == NULL) ||
1530                 (EVP_MD_CTX_md(s->write_hash) == NULL))
1531                 clear=1;
1532
1533         if (clear)
1534                 mac_size=0;
1535         else
1536                 {
1537                 mac_size=EVP_MD_CTX_size(s->write_hash);
1538                 if (mac_size < 0)
1539                         goto err;
1540                 }
1541
1542         /* DTLS implements explicit IV, so no need for empty fragments */
1543 #if 0
1544         /* 'create_empty_fragment' is true only when this function calls itself */
1545         if (!clear && !create_empty_fragment && !s->s3->empty_fragment_done
1546             && SSL_version(s) != DTLS1_VERSION && SSL_version(s) != DTLS1_BAD_VER)
1547                 {
1548                 /* countermeasure against known-IV weakness in CBC ciphersuites
1549                  * (see http://www.openssl.org/~bodo/tls-cbc.txt)
1550                  */
1551
1552                 if (s->s3->need_empty_fragments && type == SSL3_RT_APPLICATION_DATA)
1553                         {
1554                         /* recursive function call with 'create_empty_fragment' set;
1555                          * this prepares and buffers the data for an empty fragment
1556                          * (these 'prefix_len' bytes are sent out later
1557                          * together with the actual payload) */
1558                         prefix_len = s->method->do_ssl_write(s, type, buf, 0, 1);
1559                         if (prefix_len <= 0)
1560                                 goto err;
1561
1562                         if (s->s3->wbuf.len < (size_t)prefix_len + SSL3_RT_MAX_PACKET_SIZE)
1563                                 {
1564                                 /* insufficient space */
1565                                 SSLerr(SSL_F_DO_DTLS1_WRITE, ERR_R_INTERNAL_ERROR);
1566                                 goto err;
1567                                 }
1568                         }
1569
1570                 s->s3->empty_fragment_done = 1;
1571                 }
1572 #endif
1573         p = wb->buf + prefix_len;
1574
1575         /* write the header */
1576
1577         *(p++)=type&0xff;
1578         wr->type=type;
1579         /* Special case: for hello verify request, client version 1.0 and
1580          * we haven't decided which version to use yet send back using
1581          * version 1.0 header: otherwise some clients will ignore it.
1582          */
1583         if (s->method->version == DTLS_ANY_VERSION)
1584                 {
1585                 *(p++)=DTLS1_VERSION>>8;
1586                 *(p++)=DTLS1_VERSION&0xff;
1587                 }
1588         else
1589                 {
1590                 *(p++)=s->version>>8;
1591                 *(p++)=s->version&0xff;
1592                 }
1593
1594         /* field where we are to write out packet epoch, seq num and len */
1595         pseq=p;
1596         p+=10;
1597
1598         /* Explicit IV length, block ciphers appropriate version flag */
1599         if (s->enc_write_ctx)
1600                 {
1601                 int mode = EVP_CIPHER_CTX_mode(s->enc_write_ctx);
1602                 if (mode == EVP_CIPH_CBC_MODE)
1603                         {
1604                         eivlen = EVP_CIPHER_CTX_iv_length(s->enc_write_ctx);
1605                         if (eivlen <= 1)
1606                                 eivlen = 0;
1607                         }
1608                 /* Need explicit part of IV for GCM mode */
1609                 else if (mode == EVP_CIPH_GCM_MODE)
1610                         eivlen = EVP_GCM_TLS_EXPLICIT_IV_LEN;
1611                 else
1612                         eivlen = 0;
1613                 }
1614         else
1615                 eivlen = 0;
1616
1617         /* lets setup the record stuff. */
1618         wr->data=p + eivlen;  /* make room for IV in case of CBC */
1619         wr->length=(int)len;
1620         wr->input=(unsigned char *)buf;
1621
1622         /* we now 'read' from wr->input, wr->length bytes into
1623          * wr->data */
1624
1625         /* first we compress */
1626         if (s->compress != NULL)
1627                 {
1628                 if (!ssl3_do_compress(s))
1629                         {
1630                         SSLerr(SSL_F_DO_DTLS1_WRITE,SSL_R_COMPRESSION_FAILURE);
1631                         goto err;
1632                         }
1633                 }
1634         else
1635                 {
1636                 memcpy(wr->data,wr->input,wr->length);
1637                 wr->input=wr->data;
1638                 }
1639
1640         /* we should still have the output to wr->data and the input
1641          * from wr->input.  Length should be wr->length.
1642          * wr->data still points in the wb->buf */
1643
1644         if (mac_size != 0)
1645                 {
1646                 if(s->method->ssl3_enc->mac(s,&(p[wr->length + eivlen]),1) < 0)
1647                         goto err;
1648                 wr->length+=mac_size;
1649                 }
1650
1651         /* this is true regardless of mac size */
1652         wr->input=p;
1653         wr->data=p;
1654
1655         if (eivlen)
1656                 wr->length += eivlen;
1657
1658         if(s->method->ssl3_enc->enc(s,1) < 1) goto err;
1659
1660         /* record length after mac and block padding */
1661 /*      if (type == SSL3_RT_APPLICATION_DATA ||
1662         (type == SSL3_RT_ALERT && ! SSL_in_init(s))) */
1663
1664         /* there's only one epoch between handshake and app data */
1665
1666         s2n(s->d1->w_epoch, pseq);
1667
1668         /* XDTLS: ?? */
1669 /*      else
1670         s2n(s->d1->handshake_epoch, pseq); */
1671
1672         memcpy(pseq, &(s->s3->write_sequence[2]), 6);
1673         pseq+=6;
1674         s2n(wr->length,pseq);
1675
1676         if (s->msg_callback)
1677                 s->msg_callback(1, 0, SSL3_RT_HEADER, pseq - DTLS1_RT_HEADER_LENGTH, DTLS1_RT_HEADER_LENGTH, s, s->msg_callback_arg);
1678
1679         /* we should now have
1680          * wr->data pointing to the encrypted data, which is
1681          * wr->length long */
1682         wr->type=type; /* not needed but helps for debugging */
1683         wr->length+=DTLS1_RT_HEADER_LENGTH;
1684
1685 #if 0  /* this is now done at the message layer */
1686         /* buffer the record, making it easy to handle retransmits */
1687         if ( type == SSL3_RT_HANDSHAKE || type == SSL3_RT_CHANGE_CIPHER_SPEC)
1688                 dtls1_buffer_record(s, wr->data, wr->length,
1689                         *((PQ_64BIT *)&(s->s3->write_sequence[0])));
1690 #endif
1691
1692         ssl3_record_sequence_update(&(s->s3->write_sequence[0]));
1693
1694         if (create_empty_fragment)
1695                 {
1696                 /* we are in a recursive call;
1697                  * just return the length, don't write out anything here
1698                  */
1699                 return wr->length;
1700                 }
1701
1702         /* now let's set up wb */
1703         wb->left = prefix_len + wr->length;
1704         wb->offset = 0;
1705
1706         /* memorize arguments so that ssl3_write_pending can detect bad write retries later */
1707         s->s3->wpend_tot=len;
1708         s->s3->wpend_buf=buf;
1709         s->s3->wpend_type=type;
1710         s->s3->wpend_ret=len;
1711
1712         /* we now just need to write the buffer */
1713         return ssl3_write_pending(s,type,buf,len);
1714 err:
1715         return -1;
1716         }
1717
1718
1719
1720 static int dtls1_record_replay_check(SSL *s, DTLS1_BITMAP *bitmap)
1721         {
1722         int cmp;
1723         unsigned int shift;
1724         const unsigned char *seq = s->s3->read_sequence;
1725
1726         cmp = satsub64be(seq,bitmap->max_seq_num);
1727         if (cmp > 0)
1728                 {
1729                 memcpy (s->s3->rrec.seq_num,seq,8);
1730                 return 1; /* this record in new */
1731                 }
1732         shift = -cmp;
1733         if (shift >= sizeof(bitmap->map)*8)
1734                 return 0; /* stale, outside the window */
1735         else if (bitmap->map & (1UL<<shift))
1736                 return 0; /* record previously received */
1737
1738         memcpy (s->s3->rrec.seq_num,seq,8);
1739         return 1;
1740         }
1741
1742
1743 static void dtls1_record_bitmap_update(SSL *s, DTLS1_BITMAP *bitmap)
1744         {
1745         int cmp;
1746         unsigned int shift;
1747         const unsigned char *seq = s->s3->read_sequence;
1748
1749         cmp = satsub64be(seq,bitmap->max_seq_num);
1750         if (cmp > 0)
1751                 {
1752                 shift = cmp;
1753                 if (shift < sizeof(bitmap->map)*8)
1754                         bitmap->map <<= shift, bitmap->map |= 1UL;
1755                 else
1756                         bitmap->map = 1UL;
1757                 memcpy(bitmap->max_seq_num,seq,8);
1758                 }
1759         else    {
1760                 shift = -cmp;
1761                 if (shift < sizeof(bitmap->map)*8)
1762                         bitmap->map |= 1UL<<shift;
1763                 }
1764         }
1765
1766
1767 int dtls1_dispatch_alert(SSL *s)
1768         {
1769         int i,j;
1770         void (*cb)(const SSL *ssl,int type,int val)=NULL;
1771         unsigned char buf[DTLS1_AL_HEADER_LENGTH];
1772         unsigned char *ptr = &buf[0];
1773
1774         s->s3->alert_dispatch=0;
1775
1776         memset(buf, 0x00, sizeof(buf));
1777         *ptr++ = s->s3->send_alert[0];
1778         *ptr++ = s->s3->send_alert[1];
1779
1780 #ifdef DTLS1_AD_MISSING_HANDSHAKE_MESSAGE
1781         if (s->s3->send_alert[1] == DTLS1_AD_MISSING_HANDSHAKE_MESSAGE)
1782                 {
1783                 s2n(s->d1->handshake_read_seq, ptr);
1784 #if 0
1785                 if ( s->d1->r_msg_hdr.frag_off == 0)  /* waiting for a new msg */
1786
1787                 else
1788                         s2n(s->d1->r_msg_hdr.seq, ptr); /* partial msg read */
1789 #endif
1790
1791 #if 0
1792                 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);
1793 #endif
1794                 l2n3(s->d1->r_msg_hdr.frag_off, ptr);
1795                 }
1796 #endif
1797
1798         i = do_dtls1_write(s, SSL3_RT_ALERT, &buf[0], sizeof(buf), 0);
1799         if (i <= 0)
1800                 {
1801                 s->s3->alert_dispatch=1;
1802                 /* fprintf( stderr, "not done with alert\n" ); */
1803                 }
1804         else
1805                 {
1806                 if (s->s3->send_alert[0] == SSL3_AL_FATAL
1807 #ifdef DTLS1_AD_MISSING_HANDSHAKE_MESSAGE
1808                     || s->s3->send_alert[1] == DTLS1_AD_MISSING_HANDSHAKE_MESSAGE
1809 #endif
1810                     )
1811                         (void)BIO_flush(s->wbio);
1812
1813                 if (s->msg_callback)
1814                         s->msg_callback(1, s->version, SSL3_RT_ALERT, s->s3->send_alert,
1815                                 2, s, s->msg_callback_arg);
1816
1817                 if (s->info_callback != NULL)
1818                         cb=s->info_callback;
1819                 else if (s->ctx->info_callback != NULL)
1820                         cb=s->ctx->info_callback;
1821
1822                 if (cb != NULL)
1823                         {
1824                         j=(s->s3->send_alert[0]<<8)|s->s3->send_alert[1];
1825                         cb(s,SSL_CB_WRITE_ALERT,j);
1826                         }
1827                 }
1828         return(i);
1829         }
1830
1831
1832 static DTLS1_BITMAP *
1833 dtls1_get_bitmap(SSL *s, SSL3_RECORD *rr, unsigned int *is_next_epoch)
1834     {
1835
1836     *is_next_epoch = 0;
1837
1838     /* In current epoch, accept HM, CCS, DATA, & ALERT */
1839     if (rr->epoch == s->d1->r_epoch)
1840         return &s->d1->bitmap;
1841
1842     /* Only HM and ALERT messages can be from the next epoch */
1843     else if (rr->epoch == (unsigned long)(s->d1->r_epoch + 1) &&
1844         (rr->type == SSL3_RT_HANDSHAKE ||
1845             rr->type == SSL3_RT_ALERT))
1846         {
1847         *is_next_epoch = 1;
1848         return &s->d1->next_bitmap;
1849         }
1850
1851     return NULL;
1852     }
1853
1854 #if 0
1855 static int
1856 dtls1_record_needs_buffering(SSL *s, SSL3_RECORD *rr, unsigned short *priority,
1857         unsigned long *offset)
1858         {
1859
1860         /* alerts are passed up immediately */
1861         if ( rr->type == SSL3_RT_APPLICATION_DATA ||
1862                 rr->type == SSL3_RT_ALERT)
1863                 return 0;
1864
1865         /* Only need to buffer if a handshake is underway.
1866          * (this implies that Hello Request and Client Hello are passed up
1867          * immediately) */
1868         if ( SSL_in_init(s))
1869                 {
1870                 unsigned char *data = rr->data;
1871                 /* need to extract the HM/CCS sequence number here */
1872                 if ( rr->type == SSL3_RT_HANDSHAKE ||
1873                         rr->type == SSL3_RT_CHANGE_CIPHER_SPEC)
1874                         {
1875                         unsigned short seq_num;
1876                         struct hm_header_st msg_hdr;
1877                         struct ccs_header_st ccs_hdr;
1878
1879                         if ( rr->type == SSL3_RT_HANDSHAKE)
1880                                 {
1881                                 dtls1_get_message_header(data, &msg_hdr);
1882                                 seq_num = msg_hdr.seq;
1883                                 *offset = msg_hdr.frag_off;
1884                                 }
1885                         else
1886                                 {
1887                                 dtls1_get_ccs_header(data, &ccs_hdr);
1888                                 seq_num = ccs_hdr.seq;
1889                                 *offset = 0;
1890                                 }
1891
1892                         /* this is either a record we're waiting for, or a
1893                          * retransmit of something we happened to previously
1894                          * receive (higher layers will drop the repeat silently */
1895                         if ( seq_num < s->d1->handshake_read_seq)
1896                                 return 0;
1897                         if (rr->type == SSL3_RT_HANDSHAKE &&
1898                                 seq_num == s->d1->handshake_read_seq &&
1899                                 msg_hdr.frag_off < s->d1->r_msg_hdr.frag_off)
1900                                 return 0;
1901                         else if ( seq_num == s->d1->handshake_read_seq &&
1902                                 (rr->type == SSL3_RT_CHANGE_CIPHER_SPEC ||
1903                                         msg_hdr.frag_off == s->d1->r_msg_hdr.frag_off))
1904                                 return 0;
1905                         else
1906                                 {
1907                                 *priority = seq_num;
1908                                 return 1;
1909                                 }
1910                         }
1911                 else /* unknown record type */
1912                         return 0;
1913                 }
1914
1915         return 0;
1916         }
1917 #endif
1918
1919 void
1920 dtls1_reset_seq_numbers(SSL *s, int rw)
1921         {
1922         unsigned char *seq;
1923         unsigned int seq_bytes = sizeof(s->s3->read_sequence);
1924
1925         if ( rw & SSL3_CC_READ)
1926                 {
1927                 seq = s->s3->read_sequence;
1928                 s->d1->r_epoch++;
1929                 memcpy(&(s->d1->bitmap), &(s->d1->next_bitmap), sizeof(DTLS1_BITMAP));
1930                 memset(&(s->d1->next_bitmap), 0x00, sizeof(DTLS1_BITMAP));
1931                 }
1932         else
1933                 {
1934                 seq = s->s3->write_sequence;
1935                 memcpy(s->d1->last_write_sequence, seq, sizeof(s->s3->write_sequence));
1936                 s->d1->w_epoch++;
1937                 }
1938
1939         memset(seq, 0x00, seq_bytes);
1940         }