src/third_party/boringssl/src/ssl/d1_pkt.c

   1 /* DTLS implementation written by Nagendra Modadugu
   2  * (nagendra@cs.stanford.edu) for the OpenSSL project 2005. */
   3 /* ====================================================================
   4  * Copyright (c) 1998-2005 The OpenSSL Project.  All rights reserved.
   5  *
   6  * Redistribution and use in source and binary forms, with or without
   7  * modification, are permitted provided that the following conditions
   8  * are met:
   9  *
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  *
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in
  15  *    the documentation and/or other materials provided with the
  16  *    distribution.
  17  *
  18  * 3. All advertising materials mentioning features or use of this
  19  *    software must display the following acknowledgment:
  20  *    "This product includes software developed by the OpenSSL Project
  21  *    for use in the OpenSSL Toolkit. (http://www.openssl.org/)"
  22  *
  23  * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
  24  *    endorse or promote products derived from this software without
  25  *    prior written permission. For written permission, please contact
  26  *    openssl-core@openssl.org.
  27  *
  28  * 5. Products derived from this software may not be called "OpenSSL"
  29  *    nor may "OpenSSL" appear in their names without prior written
  30  *    permission of the OpenSSL Project.
  31  *
  32  * 6. Redistributions of any form whatsoever must retain the following
  33  *    acknowledgment:
  34  *    "This product includes software developed by the OpenSSL Project
  35  *    for use in the OpenSSL Toolkit (http://www.openssl.org/)"
  36  *
  37  * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
  38  * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  39  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  40  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
  41  * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  42  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  43  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  44  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  45  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
  46  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  47  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
  48  * OF THE POSSIBILITY OF SUCH DAMAGE.
  49  * ====================================================================
  50  *
  51  * This product includes cryptographic software written by Eric Young
  52  * (eay@cryptsoft.com).  This product includes software written by Tim
  53  * Hudson (tjh@cryptsoft.com).
  54  *
  55  */
  56 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
  57  * All rights reserved.
  58  *
  59  * This package is an SSL implementation written
  60  * by Eric Young (eay@cryptsoft.com).
  61  * The implementation was written so as to conform with Netscapes SSL.
  62  *
  63  * This library is free for commercial and non-commercial use as long as
  64  * the following conditions are aheared to.  The following conditions
  65  * apply to all code found in this distribution, be it the RC4, RSA,
  66  * lhash, DES, etc., code; not just the SSL code.  The SSL documentation
  67  * included with this distribution is covered by the same copyright terms
  68  * except that the holder is Tim Hudson (tjh@cryptsoft.com).
  69  *
  70  * Copyright remains Eric Young's, and as such any Copyright notices in
  71  * the code are not to be removed.
  72  * If this package is used in a product, Eric Young should be given attribution
  73  * as the author of the parts of the library used.
  74  * This can be in the form of a textual message at program startup or
  75  * in documentation (online or textual) provided with the package.
  76  *
  77  * Redistribution and use in source and binary forms, with or without
  78  * modification, are permitted provided that the following conditions
  79  * are met:
  80  * 1. Redistributions of source code must retain the copyright
  81  *    notice, this list of conditions and the following disclaimer.
  82  * 2. Redistributions in binary form must reproduce the above copyright
  83  *    notice, this list of conditions and the following disclaimer in the
  84  *    documentation and/or other materials provided with the distribution.
  85  * 3. All advertising materials mentioning features or use of this software
  86  *    must display the following acknowledgement:
  87  *    "This product includes cryptographic software written by
  88  *     Eric Young (eay@cryptsoft.com)"
  89  *    The word 'cryptographic' can be left out if the rouines from the library
  90  *    being used are not cryptographic related :-).
  91  * 4. If you include any Windows specific code (or a derivative thereof) from
  92  *    the apps directory (application code) you must include an acknowledgement:
  93  *    "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
  94  *
  95  * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
  96  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  97  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  98  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  99  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 100  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 101  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 102  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 103  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 104  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 105  * SUCH DAMAGE.
 106  *
 107  * The licence and distribution terms for any publically available version or
 108  * derivative of this code cannot be changed.  i.e. this code cannot simply be
 109  * copied and put under another distribution licence
 110  * [including the GNU Public Licence.] */
 111
 112 #include <stdio.h>
 113 #include <errno.h>
 114 #include <assert.h>
 115
 116 #include <openssl/buf.h>
 117 #include <openssl/mem.h>
 118 #include <openssl/evp.h>
 119 #include <openssl/err.h>
 120 #include <openssl/rand.h>
 121
 122 #include "ssl_locl.h"
 123 /* mod 128 saturating subtract of two 64-bit values in big-endian order */
 124 static int satsub64be(const unsigned char *v1,const unsigned char *v2)
 125 {       int ret,sat,brw,i;
 126
 127         if (sizeof(long) == 8) do
 128         {       const union { long one; char little; } is_endian = {1};
 129                 long l;
 130
 131                 if (is_endian.little)                   break;
 132                 /* not reached on little-endians */
 133                 /* following test is redundant, because input is
 134                  * always aligned, but I take no chances... */
 135                 if (((size_t)v1|(size_t)v2)&0x7)        break;
 136
 137                 l  = *((long *)v1);
 138                 l -= *((long *)v2);
 139                 if (l>128)              return 128;
 140                 else if (l<-128)        return -128;
 141                 else                    return (int)l;
 142         } while (0);
 143
 144         ret = (int)v1[7]-(int)v2[7];
 145         sat = 0;
 146         brw = ret>>8;   /* brw is either 0 or -1 */
 147         if (ret & 0x80)
 148         {       for (i=6;i>=0;i--)
 149                 {       brw += (int)v1[i]-(int)v2[i];
 150                         sat |= ~brw;
 151                         brw >>= 8;
 152                 }
 153         }
 154         else
 155         {       for (i=6;i>=0;i--)
 156                 {       brw += (int)v1[i]-(int)v2[i];
 157                         sat |= brw;
 158                         brw >>= 8;
 159                 }
 160         }
 161         brw <<= 8;      /* brw is either 0 or -256 */
 162
 163         if (sat&0xff)   return brw | 0x80;
 164         else            return brw + (ret&0xFF);
 165 }
 166
 167 static int have_handshake_fragment(SSL *s, int type, unsigned char *buf,
 168         int len, int peek);
 169 static int dtls1_record_replay_check(SSL *s, DTLS1_BITMAP *bitmap);
 170 static void dtls1_record_bitmap_update(SSL *s, DTLS1_BITMAP *bitmap);
 171 static DTLS1_BITMAP *dtls1_get_bitmap(SSL *s, SSL3_RECORD *rr,
 172     unsigned int *is_next_epoch);
 173 #if 0
 174 static int dtls1_record_needs_buffering(SSL *s, SSL3_RECORD *rr,
 175         unsigned short *priority, unsigned long *offset);
 176 #endif
 177 static int dtls1_buffer_record(SSL *s, record_pqueue *q,
 178         unsigned char *priority);
 179 static int dtls1_process_record(SSL *s);
 180 static int do_dtls1_write(SSL *s, int type, const unsigned char *buf,
 181                           unsigned int len);
 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                 OPENSSL_PUT_ERROR(SSL, 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         s->packet = NULL;
 235         s->packet_length = 0;
 236         memset(&(s->s3->rbuf), 0, sizeof(SSL3_BUFFER));
 237         memset(&(s->s3->rrec), 0, sizeof(SSL3_RECORD));
 238
 239         if (!ssl3_setup_buffers(s))
 240                 {
 241                 OPENSSL_PUT_ERROR(SSL, dtls1_buffer_record, ERR_R_INTERNAL_ERROR);
 242                 OPENSSL_free(rdata);
 243                 pitem_free(item);
 244                 return(0);
 245                 }
 246
 247         /* insert should not fail, since duplicates are dropped */
 248         if (pqueue_insert(queue->q, item) == NULL)
 249                 {
 250                 OPENSSL_PUT_ERROR(SSL, dtls1_buffer_record, ERR_R_INTERNAL_ERROR);
 251                 OPENSSL_free(rdata);
 252                 pitem_free(item);
 253                 return(0);
 254                 }
 255
 256         return(1);
 257         }
 258
 259
 260 static int
 261 dtls1_retrieve_buffered_record(SSL *s, record_pqueue *queue)
 262     {
 263     pitem *item;
 264
 265     item = pqueue_pop(queue->q);
 266     if (item)
 267         {
 268         dtls1_copy_record(s, item);
 269
 270         OPENSSL_free(item->data);
 271                 pitem_free(item);
 272
 273         return(1);
 274         }
 275
 276     return(0);
 277     }
 278
 279
 280 /* retrieve a buffered record that belongs to the new epoch, i.e., not processed
 281  * yet */
 282 #define dtls1_get_unprocessed_record(s) \
 283                    dtls1_retrieve_buffered_record((s), \
 284                    &((s)->d1->unprocessed_rcds))
 285
 286 /* retrieve a buffered record that belongs to the current epoch, ie, processed */
 287 #define dtls1_get_processed_record(s) \
 288                    dtls1_retrieve_buffered_record((s), \
 289                    &((s)->d1->processed_rcds))
 290
 291 static int
 292 dtls1_process_buffered_records(SSL *s)
 293     {
 294     pitem *item;
 295
 296     item = pqueue_peek(s->d1->unprocessed_rcds.q);
 297     if (item)
 298         {
 299         /* Check if epoch is current. */
 300         if (s->d1->unprocessed_rcds.epoch != s->d1->r_epoch)
 301             return(1);  /* Nothing to do. */
 302
 303         /* Process all the records. */
 304         while (pqueue_peek(s->d1->unprocessed_rcds.q))
 305             {
 306             dtls1_get_unprocessed_record(s);
 307             if ( ! dtls1_process_record(s))
 308                 return(0);
 309             dtls1_buffer_record(s, &(s->d1->processed_rcds),
 310                 s->s3->rrec.seq_num);
 311             }
 312         }
 313
 314     /* sync epoch numbers once all the unprocessed records
 315      * have been processed */
 316     s->d1->processed_rcds.epoch = s->d1->r_epoch;
 317     s->d1->unprocessed_rcds.epoch = s->d1->r_epoch + 1;
 318
 319     return(1);
 320     }
 321
 322
 323 #if 0
 324
 325 static int
 326 dtls1_get_buffered_record(SSL *s)
 327         {
 328         pitem *item;
 329         PQ_64BIT priority =
 330                 (((PQ_64BIT)s->d1->handshake_read_seq) << 32) |
 331                 ((PQ_64BIT)s->d1->r_msg_hdr.frag_off);
 332
 333         if ( ! SSL_in_init(s))  /* if we're not (re)negotiating,
 334                                                            nothing buffered */
 335                 return 0;
 336
 337
 338         item = pqueue_peek(s->d1->rcvd_records);
 339         if (item && item->priority == priority)
 340                 {
 341                 /* Check if we've received the record of interest.  It must be
 342                  * a handshake record, since data records as passed up without
 343                  * buffering */
 344                 DTLS1_RECORD_DATA *rdata;
 345                 item = pqueue_pop(s->d1->rcvd_records);
 346                 rdata = (DTLS1_RECORD_DATA *)item->data;
 347
 348                 if (s->s3->rbuf.buf != NULL)
 349                         OPENSSL_free(s->s3->rbuf.buf);
 350
 351                 s->packet = rdata->packet;
 352                 s->packet_length = rdata->packet_length;
 353                 memcpy(&(s->s3->rbuf), &(rdata->rbuf), sizeof(SSL3_BUFFER));
 354                 memcpy(&(s->s3->rrec), &(rdata->rrec), sizeof(SSL3_RECORD));
 355
 356                 OPENSSL_free(item->data);
 357                 pitem_free(item);
 358
 359                 /* s->d1->next_expected_seq_num++; */
 360                 return(1);
 361                 }
 362
 363         return 0;
 364         }
 365
 366 #endif
 367
 368 static int
 369 dtls1_process_record(SSL *s)
 370 {
 371         int i,al;
 372         int enc_err;
 373         SSL_SESSION *sess;
 374         SSL3_RECORD *rr;
 375         unsigned int mac_size, orig_len;
 376         unsigned char md[EVP_MAX_MD_SIZE];
 377
 378         rr= &(s->s3->rrec);
 379         sess = s->session;
 380
 381         /* At this point, s->packet_length == SSL3_RT_HEADER_LNGTH + rr->length,
 382          * and we have that many bytes in s->packet
 383          */
 384         rr->input= &(s->packet[DTLS1_RT_HEADER_LENGTH]);
 385
 386         /* ok, we can now read from 's->packet' data into 'rr'
 387          * rr->input points at rr->length bytes, which
 388          * need to be copied into rr->data by either
 389          * the decryption or by the decompression
 390          * When the data is 'copied' into the rr->data buffer,
 391          * rr->input will be pointed at the new buffer */
 392
 393         /* We now have - encrypted [ MAC [ compressed [ plain ] ] ]
 394          * rr->length bytes of encrypted compressed stuff. */
 395
 396         /* check is not needed I believe */
 397         if (rr->length > SSL3_RT_MAX_ENCRYPTED_LENGTH)
 398                 {
 399                 al=SSL_AD_RECORD_OVERFLOW;
 400                 OPENSSL_PUT_ERROR(SSL, dtls1_process_record, SSL_R_ENCRYPTED_LENGTH_TOO_LONG);
 401                 goto f_err;
 402                 }
 403
 404         /* decrypt in place in 'rr->input' */
 405         rr->data=rr->input;
 406
 407         enc_err = s->method->ssl3_enc->enc(s,0);
 408         /* enc_err is:
 409          *    0: (in non-constant time) if the record is publically invalid.
 410          *    1: if the padding is valid
 411          *    -1: if the padding is invalid */
 412         if (enc_err == 0)
 413                 {
 414                 /* For DTLS we simply ignore bad packets. */
 415                 rr->length = 0;
 416                 s->packet_length = 0;
 417                 goto err;
 418                 }
 419
 420 #ifdef TLS_DEBUG
 421 printf("dec %d\n",rr->length);
 422 { unsigned int z; for (z=0; z<rr->length; z++) printf("%02X%c",rr->data[z],((z+1)%16)?' ':'\n'); }
 423 printf("\n");
 424 #endif
 425
 426         /* r->length is now the compressed data plus mac */
 427         if ((sess != NULL) &&
 428             (s->enc_read_ctx != NULL) &&
 429             (EVP_MD_CTX_md(s->read_hash) != NULL))
 430                 {
 431                 /* s->read_hash != NULL => mac_size != -1 */
 432                 unsigned char *mac = NULL;
 433                 unsigned char mac_tmp[EVP_MAX_MD_SIZE];
 434                 mac_size=EVP_MD_CTX_size(s->read_hash);
 435                 assert(mac_size <= EVP_MAX_MD_SIZE);
 436
 437                 /* kludge: *_cbc_remove_padding passes padding length in rr->type */
 438                 orig_len = rr->length+((unsigned int)rr->type>>8);
 439
 440                 /* orig_len is the length of the record before any padding was
 441                  * removed. This is public information, as is the MAC in use,
 442                  * therefore we can safely process the record in a different
 443                  * amount of time if it's too short to possibly contain a MAC.
 444                  */
 445                 if (orig_len < mac_size ||
 446                     /* CBC records must have a padding length byte too. */
 447                     (EVP_CIPHER_CTX_mode(s->enc_read_ctx) == EVP_CIPH_CBC_MODE &&
 448                      orig_len < mac_size+1))
 449                         {
 450                         al=SSL_AD_DECODE_ERROR;
 451                         OPENSSL_PUT_ERROR(SSL, dtls1_process_record, SSL_R_LENGTH_TOO_SHORT);
 452                         goto f_err;
 453                         }
 454
 455                 if (EVP_CIPHER_CTX_mode(s->enc_read_ctx) == EVP_CIPH_CBC_MODE)
 456                         {
 457                         /* We update the length so that the TLS header bytes
 458                          * can be constructed correctly but we need to extract
 459                          * the MAC in constant time from within the record,
 460                          * without leaking the contents of the padding bytes.
 461                          * */
 462                         mac = mac_tmp;
 463                         ssl3_cbc_copy_mac(mac_tmp, rr, mac_size, orig_len);
 464                         rr->length -= mac_size;
 465                         }
 466                 else
 467                         {
 468                         /* In this case there's no padding, so |orig_len|
 469                          * equals |rec->length| and we checked that there's
 470                          * enough bytes for |mac_size| above. */
 471                         rr->length -= mac_size;
 472                         mac = &rr->data[rr->length];
 473                         }
 474
 475                 i=s->method->ssl3_enc->mac(s,md,0 /* not send */);
 476                 if (i < 0 || mac == NULL || CRYPTO_memcmp(md, mac, (size_t)mac_size) != 0)
 477                         enc_err = -1;
 478                 if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH+mac_size)
 479                         enc_err = -1;
 480                 }
 481
 482         if (enc_err < 0)
 483                 {
 484                 /* decryption failed, silently discard message */
 485                 rr->length = 0;
 486                 s->packet_length = 0;
 487                 goto err;
 488                 }
 489
 490         if (rr->length > SSL3_RT_MAX_PLAIN_LENGTH)
 491                 {
 492                 al=SSL_AD_RECORD_OVERFLOW;
 493                 OPENSSL_PUT_ERROR(SSL, dtls1_process_record, SSL_R_DATA_LENGTH_TOO_LONG);
 494                 goto f_err;
 495                 }
 496
 497         rr->off=0;
 498         /* So at this point the following is true
 499          * ssl->s3->rrec.type   is the type of record
 500          * ssl->s3->rrec.length == number of bytes in record
 501          * ssl->s3->rrec.off    == offset to first valid byte
 502          * ssl->s3->rrec.data   == where to take bytes from, increment
 503          *                         after use :-).
 504          */
 505
 506         /* we have pulled in a full packet so zero things */
 507         s->packet_length=0;
 508         dtls1_record_bitmap_update(s, &(s->d1->bitmap));/* Mark receipt of record. */
 509         return(1);
 510
 511 f_err:
 512         ssl3_send_alert(s,SSL3_AL_FATAL,al);
 513 err:
 514         return(0);
 515 }
 516
 517
 518 /* Call this to get a new input record.
 519  * It will return <= 0 if more data is needed, normally due to an error
 520  * or non-blocking IO.
 521  * When it finishes, one packet has been decoded and can be found in
 522  * ssl->s3->rrec.type    - is the type of record
 523  * ssl->s3->rrec.data,   - data
 524  * ssl->s3->rrec.length, - number of bytes
 525  */
 526 /* used only by dtls1_read_bytes */
 527 int dtls1_get_record(SSL *s)
 528         {
 529         int ssl_major,ssl_minor;
 530         int i,n;
 531         SSL3_RECORD *rr;
 532         unsigned char *p = NULL;
 533         unsigned short version;
 534         DTLS1_BITMAP *bitmap;
 535         unsigned int is_next_epoch;
 536
 537         rr= &(s->s3->rrec);
 538
 539         /* The epoch may have changed.  If so, process all the
 540          * pending records.  This is a non-blocking operation. */
 541         dtls1_process_buffered_records(s);
 542
 543         /* if we're renegotiating, then there may be buffered records */
 544         if (dtls1_get_processed_record(s))
 545                 return 1;
 546
 547         /* get something from the wire */
 548 again:
 549         /* check if we have the header */
 550         if (    (s->rstate != SSL_ST_READ_BODY) ||
 551                 (s->packet_length < DTLS1_RT_HEADER_LENGTH))
 552                 {
 553                 n=ssl3_read_n(s, DTLS1_RT_HEADER_LENGTH, s->s3->rbuf.len, 0);
 554                 /* read timeout is handled by dtls1_read_bytes */
 555                 if (n <= 0) return(n); /* error or non-blocking */
 556
 557                 /* this packet contained a partial record, dump it */
 558                 if (s->packet_length != DTLS1_RT_HEADER_LENGTH)
 559                         {
 560                         s->packet_length = 0;
 561                         goto again;
 562                         }
 563
 564                 s->rstate=SSL_ST_READ_BODY;
 565
 566                 p=s->packet;
 567
 568                 if (s->msg_callback)
 569                         s->msg_callback(0, 0, SSL3_RT_HEADER, p, DTLS1_RT_HEADER_LENGTH, s, s->msg_callback_arg);
 570
 571                 /* Pull apart the header into the DTLS1_RECORD */
 572                 rr->type= *(p++);
 573                 ssl_major= *(p++);
 574                 ssl_minor= *(p++);
 575                 version=(ssl_major<<8)|ssl_minor;
 576
 577                 /* sequence number is 64 bits, with top 2 bytes = epoch */
 578                 n2s(p,rr->epoch);
 579
 580                 memcpy(&(s->s3->read_sequence[2]), p, 6);
 581                 p+=6;
 582
 583                 n2s(p,rr->length);
 584
 585                 /* Lets check version */
 586                 if (!s->first_packet)
 587                         {
 588                         if (version != s->version)
 589                                 {
 590                                 /* unexpected version, silently discard */
 591                                 rr->length = 0;
 592                                 s->packet_length = 0;
 593                                 goto again;
 594                                 }
 595                         }
 596
 597                 if ((version & 0xff00) != (s->version & 0xff00))
 598                         {
 599                         /* wrong version, silently discard record */
 600                         rr->length = 0;
 601                         s->packet_length = 0;
 602                         goto again;
 603                         }
 604
 605                 if (rr->length > SSL3_RT_MAX_ENCRYPTED_LENGTH)
 606                         {
 607                         /* record too long, silently discard it */
 608                         rr->length = 0;
 609                         s->packet_length = 0;
 610                         goto again;
 611                         }
 612
 613                 /* now s->rstate == SSL_ST_READ_BODY */
 614                 }
 615
 616         /* s->rstate == SSL_ST_READ_BODY, get and decode the data */
 617
 618         if (rr->length > s->packet_length-DTLS1_RT_HEADER_LENGTH)
 619                 {
 620                 /* now s->packet_length == DTLS1_RT_HEADER_LENGTH */
 621                 i=rr->length;
 622                 n=ssl3_read_n(s,i,i,1);
 623                 if (n <= 0) return(n); /* error or non-blocking io */
 624
 625                 /* this packet contained a partial record, dump it */
 626                 if ( n != i)
 627                         {
 628                         rr->length = 0;
 629                         s->packet_length = 0;
 630                         goto again;
 631                         }
 632
 633                 /* now n == rr->length,
 634                  * and s->packet_length == DTLS1_RT_HEADER_LENGTH + rr->length */
 635                 }
 636         s->rstate=SSL_ST_READ_HEADER; /* set state for later operations */
 637
 638         /* match epochs.  NULL means the packet is dropped on the floor */
 639         bitmap = dtls1_get_bitmap(s, rr, &is_next_epoch);
 640         if ( bitmap == NULL)
 641                 {
 642                 rr->length = 0;
 643                 s->packet_length = 0;  /* dump this record */
 644                 goto again;   /* get another record */
 645                 }
 646
 647                 /* Check whether this is a repeat, or aged record.
 648                  * Don't check if we're listening and this message is
 649                  * a ClientHello. They can look as if they're replayed,
 650                  * since they arrive from different connections and
 651                  * would be dropped unnecessarily.
 652                  */
 653                 if (!(s->d1->listen && rr->type == SSL3_RT_HANDSHAKE &&
 654                     *p == SSL3_MT_CLIENT_HELLO) &&
 655                     !dtls1_record_replay_check(s, bitmap))
 656                         {
 657                         rr->length = 0;
 658                         s->packet_length=0; /* dump this record */
 659                         goto again;     /* get another record */
 660                         }
 661
 662         /* just read a 0 length packet */
 663         if (rr->length == 0) goto again;
 664
 665         /* If this record is from the next epoch (either HM or ALERT),
 666          * and a handshake is currently in progress, buffer it since it
 667          * cannot be processed at this time. However, do not buffer
 668          * anything while listening.
 669          */
 670         if (is_next_epoch)
 671                 {
 672                 if ((SSL_in_init(s) || s->in_handshake) && !s->d1->listen)
 673                         {
 674                         dtls1_buffer_record(s, &(s->d1->unprocessed_rcds), rr->seq_num);
 675                         }
 676                 rr->length = 0;
 677                 s->packet_length = 0;
 678                 goto again;
 679                 }
 680
 681         if (!dtls1_process_record(s))
 682                 {
 683                 rr->length = 0;
 684                 s->packet_length = 0;  /* dump this record */
 685                 goto again;   /* get another record */
 686                 }
 687
 688         return(1);
 689
 690         }
 691
 692 /* Return up to 'len' payload bytes received in 'type' records.
 693  * 'type' is one of the following:
 694  *
 695  *   -  SSL3_RT_HANDSHAKE (when ssl3_get_message calls us)
 696  *   -  SSL3_RT_APPLICATION_DATA (when ssl3_read calls us)
 697  *   -  0 (during a shutdown, no data has to be returned)
 698  *
 699  * If we don't have stored data to work from, read a SSL/TLS record first
 700  * (possibly multiple records if we still don't have anything to return).
 701  *
 702  * This function must handle any surprises the peer may have for us, such as
 703  * Alert records (e.g. close_notify), ChangeCipherSpec records (not really
 704  * a surprise, but handled as if it were), or renegotiation requests.
 705  * Also if record payloads contain fragments too small to process, we store
 706  * them until there is enough for the respective protocol (the record protocol
 707  * may use arbitrary fragmentation and even interleaving):
 708  *     Change cipher spec protocol
 709  *             just 1 byte needed, no need for keeping anything stored
 710  *     Alert protocol
 711  *             2 bytes needed (AlertLevel, AlertDescription)
 712  *     Handshake protocol
 713  *             4 bytes needed (HandshakeType, uint24 length) -- we just have
 714  *             to detect unexpected Client Hello and Hello Request messages
 715  *             here, anything else is handled by higher layers
 716  *     Application data protocol
 717  *             none of our business
 718  */
 719 int dtls1_read_bytes(SSL *s, int type, unsigned char *buf, int len, int peek)
 720         {
 721         int al,i,j,ret;
 722         unsigned int n;
 723         SSL3_RECORD *rr;
 724         void (*cb)(const SSL *ssl,int type2,int val)=NULL;
 725
 726         if (s->s3->rbuf.buf == NULL) /* Not initialized yet */
 727                 if (!ssl3_setup_buffers(s))
 728                         return(-1);
 729
 730     /* XXX: check what the second '&& type' is about */
 731         if ((type && (type != SSL3_RT_APPLICATION_DATA) &&
 732                 (type != SSL3_RT_HANDSHAKE) && type) ||
 733             (peek && (type != SSL3_RT_APPLICATION_DATA)))
 734                 {
 735                 OPENSSL_PUT_ERROR(SSL, dtls1_read_bytes, ERR_R_INTERNAL_ERROR);
 736                 return -1;
 737                 }
 738
 739         /* check whether there's a handshake message (client hello?) waiting */
 740         if ( (ret = have_handshake_fragment(s, type, buf, len, peek)))
 741                 return ret;
 742
 743         /* Now s->d1->handshake_fragment_len == 0 if type == SSL3_RT_HANDSHAKE. */
 744
 745         if (!s->in_handshake && SSL_in_init(s))
 746                 {
 747                 /* type == SSL3_RT_APPLICATION_DATA */
 748                 i=s->handshake_func(s);
 749                 if (i < 0) return(i);
 750                 if (i == 0)
 751                         {
 752                         OPENSSL_PUT_ERROR(SSL, dtls1_read_bytes, SSL_R_SSL_HANDSHAKE_FAILURE);
 753                         return(-1);
 754                         }
 755                 }
 756
 757 start:
 758         s->rwstate=SSL_NOTHING;
 759
 760         /* s->s3->rrec.type         - is the type of record
 761          * s->s3->rrec.data,    - data
 762          * s->s3->rrec.off,     - offset into 'data' for next read
 763          * s->s3->rrec.length,  - number of bytes. */
 764         rr = &(s->s3->rrec);
 765
 766         /* We are not handshaking and have no data yet,
 767          * so process data buffered during the last handshake
 768          * in advance, if any.
 769          */
 770         if (s->state == SSL_ST_OK && rr->length == 0)
 771                 {
 772                 pitem *item;
 773                 item = pqueue_pop(s->d1->buffered_app_data.q);
 774                 if (item)
 775                         {
 776                         dtls1_copy_record(s, item);
 777
 778                         OPENSSL_free(item->data);
 779                         pitem_free(item);
 780                         }
 781                 }
 782
 783         /* Check for timeout */
 784         if (dtls1_handle_timeout(s) > 0)
 785                 goto start;
 786
 787         /* get new packet if necessary */
 788         if ((rr->length == 0) || (s->rstate == SSL_ST_READ_BODY))
 789                 {
 790                 ret=dtls1_get_record(s);
 791                 if (ret <= 0)
 792                         {
 793                         ret = dtls1_read_failed(s, ret);
 794                         /* anything other than a timeout is an error */
 795                         if (ret <= 0)
 796                                 return(ret);
 797                         else
 798                                 goto start;
 799                         }
 800                 }
 801
 802         if (s->d1->listen && rr->type != SSL3_RT_HANDSHAKE)
 803                 {
 804                 rr->length = 0;
 805                 goto start;
 806                 }
 807
 808         /* we now have a packet which can be read and processed */
 809
 810         if (s->s3->change_cipher_spec /* set when we receive ChangeCipherSpec,
 811                                        * reset by ssl3_get_finished */
 812                 && (rr->type != SSL3_RT_HANDSHAKE))
 813                 {
 814                 /* We now have application data between CCS and Finished.
 815                  * Most likely the packets were reordered on their way, so
 816                  * buffer the application data for later processing rather
 817                  * than dropping the connection.
 818                  */
 819                 dtls1_buffer_record(s, &(s->d1->buffered_app_data), rr->seq_num);
 820                 rr->length = 0;
 821                 goto start;
 822                 }
 823
 824         /* If the other end has shut down, throw anything we read away
 825          * (even in 'peek' mode) */
 826         if (s->shutdown & SSL_RECEIVED_SHUTDOWN)
 827                 {
 828                 rr->length=0;
 829                 s->rwstate=SSL_NOTHING;
 830                 return(0);
 831                 }
 832
 833
 834         if (type == rr->type) /* SSL3_RT_APPLICATION_DATA or SSL3_RT_HANDSHAKE */
 835                 {
 836                 /* make sure that we are not getting application data when we
 837                  * are doing a handshake for the first time */
 838                 if (SSL_in_init(s) && (type == SSL3_RT_APPLICATION_DATA) &&
 839                         (s->enc_read_ctx == NULL))
 840                         {
 841                         al=SSL_AD_UNEXPECTED_MESSAGE;
 842                         OPENSSL_PUT_ERROR(SSL, dtls1_read_bytes, SSL_R_APP_DATA_IN_HANDSHAKE);
 843                         goto f_err;
 844                         }
 845
 846                 if (len <= 0) return(len);
 847
 848                 if ((unsigned int)len > rr->length)
 849                         n = rr->length;
 850                 else
 851                         n = (unsigned int)len;
 852
 853                 memcpy(buf,&(rr->data[rr->off]),n);
 854                 if (!peek)
 855                         {
 856                         rr->length-=n;
 857                         rr->off+=n;
 858                         if (rr->length == 0)
 859                                 {
 860                                 s->rstate=SSL_ST_READ_HEADER;
 861                                 rr->off=0;
 862                                 }
 863                         }
 864
 865                 return(n);
 866                 }
 867
 868
 869         /* If we get here, then type != rr->type; if we have a handshake
 870          * message, then it was unexpected (Hello Request or Client Hello). */
 871
 872         /* In case of record types for which we have 'fragment' storage,
 873          * fill that so that we can process the data at a fixed place.
 874          */
 875                 {
 876                 unsigned int k, dest_maxlen = 0;
 877                 unsigned char *dest = NULL;
 878                 unsigned int *dest_len = NULL;
 879
 880                 if (rr->type == SSL3_RT_HANDSHAKE)
 881                         {
 882                         dest_maxlen = sizeof s->d1->handshake_fragment;
 883                         dest = s->d1->handshake_fragment;
 884                         dest_len = &s->d1->handshake_fragment_len;
 885                         }
 886                 else if (rr->type == SSL3_RT_ALERT)
 887                         {
 888                         dest_maxlen = sizeof(s->d1->alert_fragment);
 889                         dest = s->d1->alert_fragment;
 890                         dest_len = &s->d1->alert_fragment_len;
 891                         }
 892                 /* else it's a CCS message, or application data or wrong */
 893                 else if (rr->type != SSL3_RT_CHANGE_CIPHER_SPEC)
 894                         {
 895                         /* Application data while renegotiating
 896                          * is allowed. Try again reading.
 897                          */
 898                         if (rr->type == SSL3_RT_APPLICATION_DATA)
 899                                 {
 900                                 BIO *bio;
 901                                 s->s3->in_read_app_data=2;
 902                                 bio=SSL_get_rbio(s);
 903                                 s->rwstate=SSL_READING;
 904                                 BIO_clear_retry_flags(bio);
 905                                 BIO_set_retry_read(bio);
 906                                 return(-1);
 907                                 }
 908
 909                         /* Not certain if this is the right error handling */
 910                         al=SSL_AD_UNEXPECTED_MESSAGE;
 911                         OPENSSL_PUT_ERROR(SSL, dtls1_read_bytes, SSL_R_UNEXPECTED_RECORD);
 912                         goto f_err;
 913                         }
 914
 915                 if (dest_maxlen > 0)
 916                         {
 917             /* XDTLS:  In a pathalogical case, the Client Hello
 918              *  may be fragmented--don't always expect dest_maxlen bytes */
 919                         if ( rr->length < dest_maxlen)
 920                                 {
 921                                 s->rstate=SSL_ST_READ_HEADER;
 922                                 rr->length = 0;
 923                                 goto start;
 924                                 }
 925
 926                         /* now move 'n' bytes: */
 927                         for ( k = 0; k < dest_maxlen; k++)
 928                                 {
 929                                 dest[k] = rr->data[rr->off++];
 930                                 rr->length--;
 931                                 }
 932                         *dest_len = dest_maxlen;
 933                         }
 934                 }
 935
 936         /* s->d1->handshake_fragment_len == 12  iff  rr->type == SSL3_RT_HANDSHAKE;
 937          * s->d1->alert_fragment_len == 7      iff  rr->type == SSL3_RT_ALERT.
 938          * (Possibly rr is 'empty' now, i.e. rr->length may be 0.) */
 939
 940         /* If we are a client, check for an incoming 'Hello Request': */
 941         if ((!s->server) &&
 942                 (s->d1->handshake_fragment_len >= DTLS1_HM_HEADER_LENGTH) &&
 943                 (s->d1->handshake_fragment[0] == SSL3_MT_HELLO_REQUEST) &&
 944                 (s->session != NULL) && (s->session->cipher != NULL))
 945                 {
 946                 s->d1->handshake_fragment_len = 0;
 947
 948                 if ((s->d1->handshake_fragment[1] != 0) ||
 949                         (s->d1->handshake_fragment[2] != 0) ||
 950                         (s->d1->handshake_fragment[3] != 0))
 951                         {
 952                         al=SSL_AD_DECODE_ERROR;
 953                         OPENSSL_PUT_ERROR(SSL, dtls1_read_bytes, SSL_R_BAD_HELLO_REQUEST);
 954                         goto f_err;
 955                         }
 956
 957                 /* no need to check sequence number on HELLO REQUEST messages */
 958
 959                 if (s->msg_callback)
 960                         s->msg_callback(0, s->version, SSL3_RT_HANDSHAKE,
 961                                 s->d1->handshake_fragment, 4, s, s->msg_callback_arg);
 962
 963                 if (SSL_is_init_finished(s) &&
 964                         !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS) &&
 965                         !s->s3->renegotiate)
 966                         {
 967                         s->d1->handshake_read_seq++;
 968                         s->new_session = 1;
 969                         ssl3_renegotiate(s);
 970                         if (ssl3_renegotiate_check(s))
 971                                 {
 972                                 i=s->handshake_func(s);
 973                                 if (i < 0) return(i);
 974                                 if (i == 0)
 975                                         {
 976                                         OPENSSL_PUT_ERROR(SSL, dtls1_read_bytes, SSL_R_SSL_HANDSHAKE_FAILURE);
 977                                         return(-1);
 978                                         }
 979                                 }
 980                         }
 981                 /* we either finished a handshake or ignored the request,
 982                  * now try again to obtain the (application) data we were asked for */
 983                 goto start;
 984                 }
 985
 986         if (s->d1->alert_fragment_len >= DTLS1_AL_HEADER_LENGTH)
 987                 {
 988                 int alert_level = s->d1->alert_fragment[0];
 989                 int alert_descr = s->d1->alert_fragment[1];
 990
 991                 s->d1->alert_fragment_len = 0;
 992
 993                 if (s->msg_callback)
 994                         s->msg_callback(0, s->version, SSL3_RT_ALERT,
 995                                 s->d1->alert_fragment, 2, s, s->msg_callback_arg);
 996
 997                 if (s->info_callback != NULL)
 998                         cb=s->info_callback;
 999                 else if (s->ctx->info_callback != NULL)
1000                         cb=s->ctx->info_callback;
1001
1002                 if (cb != NULL)
1003                         {
1004                         j = (alert_level << 8) | alert_descr;
1005                         cb(s, SSL_CB_READ_ALERT, j);
1006                         }
1007
1008                 if (alert_level == 1) /* warning */
1009                         {
1010                         s->s3->warn_alert = alert_descr;
1011                         if (alert_descr == SSL_AD_CLOSE_NOTIFY)
1012                                 {
1013                                 s->shutdown |= SSL_RECEIVED_SHUTDOWN;
1014                                 return(0);
1015                                 }
1016                         }
1017                 else if (alert_level == 2) /* fatal */
1018                         {
1019                         char tmp[16];
1020
1021                         s->rwstate=SSL_NOTHING;
1022                         s->s3->fatal_alert = alert_descr;
1023                         OPENSSL_PUT_ERROR(SSL, dtls1_read_bytes, SSL_AD_REASON_OFFSET + alert_descr);
1024                         BIO_snprintf(tmp,sizeof tmp,"%d",alert_descr);
1025                         ERR_add_error_data(2,"SSL alert number ",tmp);
1026                         s->shutdown|=SSL_RECEIVED_SHUTDOWN;
1027                         SSL_CTX_remove_session(s->ctx,s->session);
1028                         return(0);
1029                         }
1030                 else
1031                         {
1032                         al=SSL_AD_ILLEGAL_PARAMETER;
1033                         OPENSSL_PUT_ERROR(SSL, dtls1_read_bytes, SSL_R_UNKNOWN_ALERT_TYPE);
1034                         goto f_err;
1035                         }
1036
1037                 goto start;
1038                 }
1039
1040         if (s->shutdown & SSL_SENT_SHUTDOWN) /* but we have not received a shutdown */
1041                 {
1042                 s->rwstate=SSL_NOTHING;
1043                 rr->length=0;
1044                 return(0);
1045                 }
1046
1047         if (rr->type == SSL3_RT_CHANGE_CIPHER_SPEC)
1048                 {
1049                 struct ccs_header_st ccs_hdr;
1050                 unsigned int ccs_hdr_len = DTLS1_CCS_HEADER_LENGTH;
1051
1052                 dtls1_get_ccs_header(rr->data, &ccs_hdr);
1053
1054                 /* 'Change Cipher Spec' is just a single byte, so we know
1055                  * exactly what the record payload has to look like */
1056                 /* XDTLS: check that epoch is consistent */
1057                 if (    (rr->length != ccs_hdr_len) ||
1058                         (rr->off != 0) || (rr->data[0] != SSL3_MT_CCS))
1059                         {
1060                         al=SSL_AD_ILLEGAL_PARAMETER;
1061                         OPENSSL_PUT_ERROR(SSL, dtls1_read_bytes, SSL_R_BAD_CHANGE_CIPHER_SPEC);
1062                         goto f_err;
1063                         }
1064
1065                 rr->length=0;
1066
1067                 if (s->msg_callback)
1068                         s->msg_callback(0, s->version, SSL3_RT_CHANGE_CIPHER_SPEC,
1069                                 rr->data, 1, s, s->msg_callback_arg);
1070
1071                 /* We can't process a CCS now, because previous handshake
1072                  * messages are still missing, so just drop it.
1073                  */
1074                 if (!s->d1->change_cipher_spec_ok)
1075                         {
1076                         goto start;
1077                         }
1078
1079                 s->d1->change_cipher_spec_ok = 0;
1080
1081                 s->s3->change_cipher_spec=1;
1082                 if (!ssl3_do_change_cipher_spec(s))
1083                         goto err;
1084
1085                 /* do this whenever CCS is processed */
1086                 dtls1_reset_seq_numbers(s, SSL3_CC_READ);
1087
1088                 goto start;
1089                 }
1090
1091         /* Unexpected handshake message (Client Hello, or protocol violation) */
1092         if ((s->d1->handshake_fragment_len >= DTLS1_HM_HEADER_LENGTH) &&
1093                 !s->in_handshake)
1094                 {
1095                 struct hm_header_st msg_hdr;
1096
1097                 /* this may just be a stale retransmit */
1098                 dtls1_get_message_header(rr->data, &msg_hdr);
1099                 if( rr->epoch != s->d1->r_epoch)
1100                         {
1101                         rr->length = 0;
1102                         goto start;
1103                         }
1104
1105                 /* If we are server, we may have a repeated FINISHED of the
1106                  * client here, then retransmit our CCS and FINISHED.
1107                  */
1108                 if (msg_hdr.type == SSL3_MT_FINISHED)
1109                         {
1110                         if (dtls1_check_timeout_num(s) < 0)
1111                                 return -1;
1112
1113                         dtls1_retransmit_buffered_messages(s);
1114                         rr->length = 0;
1115                         goto start;
1116                         }
1117
1118                 if (((s->state&SSL_ST_MASK) == SSL_ST_OK) &&
1119                         !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS))
1120                         {
1121 #if 0 /* worked only because C operator preferences are not as expected (and
1122        * because this is not really needed for clients except for detecting
1123        * protocol violations): */
1124                         s->state=SSL_ST_BEFORE|(s->server)
1125                                 ?SSL_ST_ACCEPT
1126                                 :SSL_ST_CONNECT;
1127 #else
1128                         s->state = s->server ? SSL_ST_ACCEPT : SSL_ST_CONNECT;
1129 #endif
1130                         s->renegotiate=1;
1131                         s->new_session=1;
1132                         }
1133                 i=s->handshake_func(s);
1134                 if (i < 0) return(i);
1135                 if (i == 0)
1136                         {
1137                         OPENSSL_PUT_ERROR(SSL, dtls1_read_bytes, SSL_R_SSL_HANDSHAKE_FAILURE);
1138                         return(-1);
1139                         }
1140
1141                 goto start;
1142                 }
1143
1144         switch (rr->type)
1145                 {
1146         default:
1147                 /* TLS just ignores unknown message types */
1148                 if (s->version == TLS1_VERSION)
1149                         {
1150                         rr->length = 0;
1151                         goto start;
1152                         }
1153                 al=SSL_AD_UNEXPECTED_MESSAGE;
1154                 OPENSSL_PUT_ERROR(SSL, dtls1_read_bytes, SSL_R_UNEXPECTED_RECORD);
1155                 goto f_err;
1156         case SSL3_RT_CHANGE_CIPHER_SPEC:
1157         case SSL3_RT_ALERT:
1158         case SSL3_RT_HANDSHAKE:
1159                 /* we already handled all of these, with the possible exception
1160                  * of SSL3_RT_HANDSHAKE when s->in_handshake is set, but that
1161                  * should not happen when type != rr->type */
1162                 al=SSL_AD_UNEXPECTED_MESSAGE;
1163                 OPENSSL_PUT_ERROR(SSL, dtls1_read_bytes, ERR_R_INTERNAL_ERROR);
1164                 goto f_err;
1165         case SSL3_RT_APPLICATION_DATA:
1166                 /* At this point, we were expecting handshake data,
1167                  * but have application data.  If the library was
1168                  * running inside ssl3_read() (i.e. in_read_app_data
1169                  * is set) and it makes sense to read application data
1170                  * at this point (session renegotiation not yet started),
1171                  * we will indulge it.
1172                  */
1173                 if (s->s3->in_read_app_data &&
1174                         (s->s3->total_renegotiations != 0) &&
1175                         ((
1176                                 (s->state & SSL_ST_CONNECT) &&
1177                                 (s->state >= SSL3_ST_CW_CLNT_HELLO_A) &&
1178                                 (s->state <= SSL3_ST_CR_SRVR_HELLO_A)
1179                                 ) || (
1180                                         (s->state & SSL_ST_ACCEPT) &&
1181                                         (s->state <= SSL3_ST_SW_HELLO_REQ_A) &&
1182                                         (s->state >= SSL3_ST_SR_CLNT_HELLO_A)
1183                                         )
1184                                 ))
1185                         {
1186                         s->s3->in_read_app_data=2;
1187                         return(-1);
1188                         }
1189                 else
1190                         {
1191                         al=SSL_AD_UNEXPECTED_MESSAGE;
1192                         OPENSSL_PUT_ERROR(SSL, dtls1_read_bytes, SSL_R_UNEXPECTED_RECORD);
1193                         goto f_err;
1194                         }
1195                 }
1196         /* not reached */
1197
1198 f_err:
1199         ssl3_send_alert(s,SSL3_AL_FATAL,al);
1200 err:
1201         return(-1);
1202         }
1203
1204 int
1205 dtls1_write_app_data_bytes(SSL *s, int type, const void *buf_, int len)
1206         {
1207         int i;
1208
1209                 if (SSL_in_init(s) && !s->in_handshake)
1210                 {
1211                 i=s->handshake_func(s);
1212                 if (i < 0) return(i);
1213                 if (i == 0)
1214                         {
1215                         OPENSSL_PUT_ERROR(SSL, dtls1_write_app_data_bytes, SSL_R_SSL_HANDSHAKE_FAILURE);
1216                         return -1;
1217                         }
1218                 }
1219
1220         if (len > SSL3_RT_MAX_PLAIN_LENGTH)
1221                 {
1222                         OPENSSL_PUT_ERROR(SSL, dtls1_write_app_data_bytes, SSL_R_DTLS_MESSAGE_TOO_BIG);
1223                         return -1;
1224                 }
1225
1226         i = dtls1_write_bytes(s, type, buf_, len);
1227         return i;
1228         }
1229
1230
1231         /* this only happens when a client hello is received and a handshake
1232          * is started. */
1233 static int
1234 have_handshake_fragment(SSL *s, int type, unsigned char *buf,
1235         int len, int peek)
1236         {
1237
1238         if ((type == SSL3_RT_HANDSHAKE) && (s->d1->handshake_fragment_len > 0))
1239                 /* (partially) satisfy request from storage */
1240                 {
1241                 unsigned char *src = s->d1->handshake_fragment;
1242                 unsigned char *dst = buf;
1243                 unsigned int k,n;
1244
1245                 /* peek == 0 */
1246                 n = 0;
1247                 while ((len > 0) && (s->d1->handshake_fragment_len > 0))
1248                         {
1249                         *dst++ = *src++;
1250                         len--; s->d1->handshake_fragment_len--;
1251                         n++;
1252                         }
1253                 /* move any remaining fragment bytes: */
1254                 for (k = 0; k < s->d1->handshake_fragment_len; k++)
1255                         s->d1->handshake_fragment[k] = *src++;
1256                 return n;
1257                 }
1258
1259         return 0;
1260         }
1261
1262
1263
1264
1265 /* Call this to write data in records of type 'type'
1266  * It will return <= 0 if not all data has been sent or non-blocking IO.
1267  */
1268 int dtls1_write_bytes(SSL *s, int type, const void *buf, int len)
1269         {
1270         int i;
1271
1272         assert(len <= SSL3_RT_MAX_PLAIN_LENGTH);
1273         s->rwstate=SSL_NOTHING;
1274         i=do_dtls1_write(s, type, buf, len);
1275         return i;
1276         }
1277
1278 static int do_dtls1_write(SSL *s, int type, const unsigned char *buf,
1279                           unsigned int len)
1280         {
1281         unsigned char *p,*pseq;
1282         int i,mac_size,clear=0;
1283         int prefix_len = 0;
1284         int eivlen;
1285         SSL3_RECORD *wr;
1286         SSL3_BUFFER *wb;
1287         SSL_SESSION *sess;
1288
1289         /* first check if there is a SSL3_BUFFER still being written
1290          * out.  This will happen with non blocking IO */
1291         if (s->s3->wbuf.left != 0)
1292                 {
1293                 assert(0); /* XDTLS:  want to see if we ever get here */
1294                 return(ssl3_write_pending(s,type,buf,len));
1295                 }
1296
1297         /* If we have an alert to send, lets send it */
1298         if (s->s3->alert_dispatch)
1299                 {
1300                 i=s->method->ssl_dispatch_alert(s);
1301                 if (i <= 0)
1302                         return(i);
1303                 /* if it went, fall through and send more stuff */
1304                 }
1305
1306         if (len == 0)
1307                 return 0;
1308
1309         wr= &(s->s3->wrec);
1310         wb= &(s->s3->wbuf);
1311         sess=s->session;
1312
1313         if (    (sess == NULL) ||
1314                 (s->enc_write_ctx == NULL) ||
1315                 (EVP_MD_CTX_md(s->write_hash) == NULL))
1316                 clear=1;
1317
1318         if (clear)
1319                 mac_size=0;
1320         else
1321                 {
1322                 mac_size=EVP_MD_CTX_size(s->write_hash);
1323                 if (mac_size < 0)
1324                         goto err;
1325                 }
1326
1327         p = wb->buf + prefix_len;
1328
1329         /* write the header */
1330
1331         *(p++)=type&0xff;
1332         wr->type=type;
1333         /* Special case: for hello verify request, client version 1.0 and
1334          * we haven't decided which version to use yet send back using
1335          * version 1.0 header: otherwise some clients will ignore it.
1336          */
1337         if (s->method->version == DTLS_ANY_VERSION)
1338                 {
1339                 *(p++)=DTLS1_VERSION>>8;
1340                 *(p++)=DTLS1_VERSION&0xff;
1341                 }
1342         else
1343                 {
1344                 *(p++)=s->version>>8;
1345                 *(p++)=s->version&0xff;
1346                 }
1347
1348         /* field where we are to write out packet epoch, seq num and len */
1349         pseq=p;
1350         p+=10;
1351
1352         /* Explicit IV length, block ciphers appropriate version flag */
1353         if (s->enc_write_ctx)
1354                 {
1355                 int mode = EVP_CIPHER_CTX_mode(s->enc_write_ctx);
1356                 if (mode == EVP_CIPH_CBC_MODE)
1357                         {
1358                         eivlen = EVP_CIPHER_CTX_iv_length(s->enc_write_ctx);
1359                         if (eivlen <= 1)
1360                                 eivlen = 0;
1361                         }
1362                 /* Need explicit part of IV for GCM mode */
1363                 else if (mode == EVP_CIPH_GCM_MODE)
1364                         eivlen = EVP_GCM_TLS_EXPLICIT_IV_LEN;
1365                 else
1366                         eivlen = 0;
1367                 }
1368         else
1369                 eivlen = 0;
1370
1371         /* lets setup the record stuff. */
1372         wr->data=p + eivlen;  /* make room for IV in case of CBC */
1373         wr->length=(int)len;
1374         wr->input=(unsigned char *)buf;
1375
1376         /* we now 'read' from wr->input, wr->length bytes into
1377          * wr->data */
1378
1379         memcpy(wr->data,wr->input,wr->length);
1380         wr->input=wr->data;
1381
1382         /* we should still have the output to wr->data and the input
1383          * from wr->input.  Length should be wr->length.
1384          * wr->data still points in the wb->buf */
1385
1386         if (mac_size != 0)
1387                 {
1388                 if(s->method->ssl3_enc->mac(s,&(p[wr->length + eivlen]),1) < 0)
1389                         goto err;
1390                 wr->length+=mac_size;
1391                 }
1392
1393         /* this is true regardless of mac size */
1394         wr->input=p;
1395         wr->data=p;
1396
1397         if (eivlen)
1398                 wr->length += eivlen;
1399
1400         s->method->ssl3_enc->enc(s,1);
1401
1402         /* record length after mac and block padding */
1403 /*      if (type == SSL3_RT_APPLICATION_DATA ||
1404         (type == SSL3_RT_ALERT && ! SSL_in_init(s))) */
1405
1406         /* there's only one epoch between handshake and app data */
1407
1408         s2n(s->d1->w_epoch, pseq);
1409
1410         /* XDTLS: ?? */
1411 /*      else
1412         s2n(s->d1->handshake_epoch, pseq); */
1413
1414         memcpy(pseq, &(s->s3->write_sequence[2]), 6);
1415         pseq+=6;
1416         s2n(wr->length,pseq);
1417
1418         if (s->msg_callback)
1419                 s->msg_callback(1, 0, SSL3_RT_HEADER, pseq - DTLS1_RT_HEADER_LENGTH, DTLS1_RT_HEADER_LENGTH, s, s->msg_callback_arg);
1420
1421         /* we should now have
1422          * wr->data pointing to the encrypted data, which is
1423          * wr->length long */
1424         wr->type=type; /* not needed but helps for debugging */
1425         wr->length+=DTLS1_RT_HEADER_LENGTH;
1426
1427 #if 0  /* this is now done at the message layer */
1428         /* buffer the record, making it easy to handle retransmits */
1429         if ( type == SSL3_RT_HANDSHAKE || type == SSL3_RT_CHANGE_CIPHER_SPEC)
1430                 dtls1_buffer_record(s, wr->data, wr->length,
1431                         *((PQ_64BIT *)&(s->s3->write_sequence[0])));
1432 #endif
1433
1434         ssl3_record_sequence_update(&(s->s3->write_sequence[0]));
1435
1436         /* now let's set up wb */
1437         wb->left = prefix_len + wr->length;
1438         wb->offset = 0;
1439
1440         /* memorize arguments so that ssl3_write_pending can detect bad write retries later */
1441         s->s3->wpend_tot=len;
1442         s->s3->wpend_buf=buf;
1443         s->s3->wpend_type=type;
1444         s->s3->wpend_ret=len;
1445
1446         /* we now just need to write the buffer */
1447         return ssl3_write_pending(s,type,buf,len);
1448 err:
1449         return -1;
1450         }
1451
1452
1453
1454 static int dtls1_record_replay_check(SSL *s, DTLS1_BITMAP *bitmap)
1455         {
1456         int cmp;
1457         unsigned int shift;
1458         const unsigned char *seq = s->s3->read_sequence;
1459
1460         cmp = satsub64be(seq,bitmap->max_seq_num);
1461         if (cmp > 0)
1462                 {
1463                 memcpy (s->s3->rrec.seq_num,seq,8);
1464                 return 1; /* this record in new */
1465                 }
1466         shift = -cmp;
1467         if (shift >= sizeof(bitmap->map)*8)
1468                 return 0; /* stale, outside the window */
1469         else if (bitmap->map & (1UL<<shift))
1470                 return 0; /* record previously received */
1471
1472         memcpy (s->s3->rrec.seq_num,seq,8);
1473         return 1;
1474         }
1475
1476
1477 static void dtls1_record_bitmap_update(SSL *s, DTLS1_BITMAP *bitmap)
1478         {
1479         int cmp;
1480         unsigned int shift;
1481         const unsigned char *seq = s->s3->read_sequence;
1482
1483         cmp = satsub64be(seq,bitmap->max_seq_num);
1484         if (cmp > 0)
1485                 {
1486                 shift = cmp;
1487                 if (shift < sizeof(bitmap->map)*8)
1488                         bitmap->map <<= shift, bitmap->map |= 1UL;
1489                 else
1490                         bitmap->map = 1UL;
1491                 memcpy(bitmap->max_seq_num,seq,8);
1492                 }
1493         else    {
1494                 shift = -cmp;
1495                 if (shift < sizeof(bitmap->map)*8)
1496                         bitmap->map |= 1UL<<shift;
1497                 }
1498         }
1499
1500
1501 int dtls1_dispatch_alert(SSL *s)
1502         {
1503         int i,j;
1504         void (*cb)(const SSL *ssl,int type,int val)=NULL;
1505         unsigned char buf[DTLS1_AL_HEADER_LENGTH];
1506         unsigned char *ptr = &buf[0];
1507
1508         s->s3->alert_dispatch=0;
1509
1510         memset(buf, 0x00, sizeof(buf));
1511         *ptr++ = s->s3->send_alert[0];
1512         *ptr++ = s->s3->send_alert[1];
1513
1514         i = do_dtls1_write(s, SSL3_RT_ALERT, &buf[0], sizeof(buf));
1515         if (i <= 0)
1516                 {
1517                 s->s3->alert_dispatch=1;
1518                 /* fprintf( stderr, "not done with alert\n" ); */
1519                 }
1520         else
1521                 {
1522                 if (s->s3->send_alert[0] == SSL3_AL_FATAL)
1523                         (void)BIO_flush(s->wbio);
1524
1525                 if (s->msg_callback)
1526                         s->msg_callback(1, s->version, SSL3_RT_ALERT, s->s3->send_alert,
1527                                 2, s, s->msg_callback_arg);
1528
1529                 if (s->info_callback != NULL)
1530                         cb=s->info_callback;
1531                 else if (s->ctx->info_callback != NULL)
1532                         cb=s->ctx->info_callback;
1533
1534                 if (cb != NULL)
1535                         {
1536                         j=(s->s3->send_alert[0]<<8)|s->s3->send_alert[1];
1537                         cb(s,SSL_CB_WRITE_ALERT,j);
1538                         }
1539                 }
1540         return(i);
1541         }
1542
1543
1544 static DTLS1_BITMAP *
1545 dtls1_get_bitmap(SSL *s, SSL3_RECORD *rr, unsigned int *is_next_epoch)
1546     {
1547
1548     *is_next_epoch = 0;
1549
1550     /* In current epoch, accept HM, CCS, DATA, & ALERT */
1551     if (rr->epoch == s->d1->r_epoch)
1552         return &s->d1->bitmap;
1553
1554     /* Only HM and ALERT messages can be from the next epoch */
1555     else if (rr->epoch == (unsigned long)(s->d1->r_epoch + 1) &&
1556         (rr->type == SSL3_RT_HANDSHAKE ||
1557             rr->type == SSL3_RT_ALERT))
1558         {
1559         *is_next_epoch = 1;
1560         return &s->d1->next_bitmap;
1561         }
1562
1563     return NULL;
1564     }
1565
1566 #if 0
1567 static int
1568 dtls1_record_needs_buffering(SSL *s, SSL3_RECORD *rr, unsigned short *priority,
1569         unsigned long *offset)
1570         {
1571
1572         /* alerts are passed up immediately */
1573         if ( rr->type == SSL3_RT_APPLICATION_DATA ||
1574                 rr->type == SSL3_RT_ALERT)
1575                 return 0;
1576
1577         /* Only need to buffer if a handshake is underway.
1578          * (this implies that Hello Request and Client Hello are passed up
1579          * immediately) */
1580         if ( SSL_in_init(s))
1581                 {
1582                 unsigned char *data = rr->data;
1583                 /* need to extract the HM/CCS sequence number here */
1584                 if ( rr->type == SSL3_RT_HANDSHAKE ||
1585                         rr->type == SSL3_RT_CHANGE_CIPHER_SPEC)
1586                         {
1587                         unsigned short seq_num;
1588                         struct hm_header_st msg_hdr;
1589                         struct ccs_header_st ccs_hdr;
1590
1591                         if ( rr->type == SSL3_RT_HANDSHAKE)
1592                                 {
1593                                 dtls1_get_message_header(data, &msg_hdr);
1594                                 seq_num = msg_hdr.seq;
1595                                 *offset = msg_hdr.frag_off;
1596                                 }
1597                         else
1598                                 {
1599                                 dtls1_get_ccs_header(data, &ccs_hdr);
1600                                 seq_num = ccs_hdr.seq;
1601                                 *offset = 0;
1602                                 }
1603
1604                         /* this is either a record we're waiting for, or a
1605                          * retransmit of something we happened to previously
1606                          * receive (higher layers will drop the repeat silently */
1607                         if ( seq_num < s->d1->handshake_read_seq)
1608                                 return 0;
1609                         if (rr->type == SSL3_RT_HANDSHAKE &&
1610                                 seq_num == s->d1->handshake_read_seq &&
1611                                 msg_hdr.frag_off < s->d1->r_msg_hdr.frag_off)
1612                                 return 0;
1613                         else if ( seq_num == s->d1->handshake_read_seq &&
1614                                 (rr->type == SSL3_RT_CHANGE_CIPHER_SPEC ||
1615                                         msg_hdr.frag_off == s->d1->r_msg_hdr.frag_off))
1616                                 return 0;
1617                         else
1618                                 {
1619                                 *priority = seq_num;
1620                                 return 1;
1621                                 }
1622                         }
1623                 else /* unknown record type */
1624                         return 0;
1625                 }
1626
1627         return 0;
1628         }
1629 #endif
1630
1631 void
1632 dtls1_reset_seq_numbers(SSL *s, int rw)
1633         {
1634         unsigned char *seq;
1635         unsigned int seq_bytes = sizeof(s->s3->read_sequence);
1636
1637         if ( rw & SSL3_CC_READ)
1638                 {
1639                 seq = s->s3->read_sequence;
1640                 s->d1->r_epoch++;
1641                 memcpy(&(s->d1->bitmap), &(s->d1->next_bitmap), sizeof(DTLS1_BITMAP));
1642                 memset(&(s->d1->next_bitmap), 0x00, sizeof(DTLS1_BITMAP));
1643                 }
1644         else
1645                 {
1646                 seq = s->s3->write_sequence;
1647                 memcpy(s->d1->last_write_sequence, seq, sizeof(s->s3->write_sequence));
1648                 s->d1->w_epoch++;
1649                 }
1650
1651         memset(seq, 0x00, seq_bytes);
1652         }