d1_pkt.c revision 306195
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 */ 126static int satsub64be(const unsigned char *v1, const unsigned char *v2) 127{ 128 int ret, i; 129 130 if (sizeof(long) == 8) 131 do { 132 const union { 133 long one; 134 char little; 135 } is_endian = { 136 1 137 }; 138 long l; 139 140 if (is_endian.little) 141 break; 142 /* not reached on little-endians */ 143 /* 144 * following test is redundant, because input is always aligned, 145 * but I take no chances... 146 */ 147 if (((size_t)v1 | (size_t)v2) & 0x7) 148 break; 149 150 l = *((long *)v1); 151 l -= *((long *)v2); 152 if (l > 128) 153 return 128; 154 else if (l < -128) 155 return -128; 156 else 157 return (int)l; 158 } while (0); 159 160 ret = 0; 161 for (i=0; i<7; i++) { 162 if (v1[i] > v2[i]) { 163 /* v1 is larger... but by how much? */ 164 if (v1[i] != v2[i] + 1) 165 return 128; 166 while (++i <= 6) { 167 if (v1[i] != 0x00 || v2[i] != 0xff) 168 return 128; /* too much */ 169 } 170 /* We checked all the way to the penultimate byte, 171 * so despite higher bytes changing we actually 172 * know that it only changed from (e.g.) 173 * ... (xx) ff ff ff ?? 174 * to ... (xx+1) 00 00 00 ?? 175 * so we add a 'bias' of 256 for the carry that 176 * happened, and will eventually return 177 * 256 + v1[7] - v2[7]. */ 178 ret = 256; 179 break; 180 } else if (v2[i] > v1[i]) { 181 /* v2 is larger... but by how much? */ 182 if (v2[i] != v1[i] + 1) 183 return -128; 184 while (++i <= 6) { 185 if (v2[i] != 0x00 || v1[i] != 0xff) 186 return -128; /* too much */ 187 } 188 /* Similar to the case above, we know it changed 189 * from ... (xx) 00 00 00 ?? 190 * to ... (xx-1) ff ff ff ?? 191 * so we add a 'bias' of -256 for the borrow, 192 * to return -256 + v1[7] - v2[7]. */ 193 ret = -256; 194 } 195 } 196 197 ret += (int)v1[7] - (int)v2[7]; 198 199 if (ret > 128) 200 return 128; 201 else if (ret < -128) 202 return -128; 203 else 204 return ret; 205} 206 207static int have_handshake_fragment(SSL *s, int type, unsigned char *buf, 208 int len, int peek); 209static int dtls1_record_replay_check(SSL *s, DTLS1_BITMAP *bitmap); 210static void dtls1_record_bitmap_update(SSL *s, DTLS1_BITMAP *bitmap); 211static DTLS1_BITMAP *dtls1_get_bitmap(SSL *s, SSL3_RECORD *rr, 212 unsigned int *is_next_epoch); 213#if 0 214static int dtls1_record_needs_buffering(SSL *s, SSL3_RECORD *rr, 215 unsigned short *priority, 216 unsigned long *offset); 217#endif 218static int dtls1_buffer_record(SSL *s, record_pqueue *q, 219 unsigned char *priority); 220static int dtls1_process_record(SSL *s, DTLS1_BITMAP *bitmap); 221 222/* copy buffered record into SSL structure */ 223static int dtls1_copy_record(SSL *s, pitem *item) 224{ 225 DTLS1_RECORD_DATA *rdata; 226 227 rdata = (DTLS1_RECORD_DATA *)item->data; 228 229 if (s->s3->rbuf.buf != NULL) 230 OPENSSL_free(s->s3->rbuf.buf); 231 232 s->packet = rdata->packet; 233 s->packet_length = rdata->packet_length; 234 memcpy(&(s->s3->rbuf), &(rdata->rbuf), sizeof(SSL3_BUFFER)); 235 memcpy(&(s->s3->rrec), &(rdata->rrec), sizeof(SSL3_RECORD)); 236 237 /* Set proper sequence number for mac calculation */ 238 memcpy(&(s->s3->read_sequence[2]), &(rdata->packet[5]), 6); 239 240 return (1); 241} 242 243static int 244dtls1_buffer_record(SSL *s, record_pqueue *queue, unsigned char *priority) 245{ 246 DTLS1_RECORD_DATA *rdata; 247 pitem *item; 248 249 /* Limit the size of the queue to prevent DOS attacks */ 250 if (pqueue_size(queue->q) >= 100) 251 return 0; 252 253 rdata = OPENSSL_malloc(sizeof(DTLS1_RECORD_DATA)); 254 item = pitem_new(priority, rdata); 255 if (rdata == NULL || item == NULL) { 256 if (rdata != NULL) 257 OPENSSL_free(rdata); 258 if (item != NULL) 259 pitem_free(item); 260 261 SSLerr(SSL_F_DTLS1_BUFFER_RECORD, ERR_R_INTERNAL_ERROR); 262 return -1; 263 } 264 265 rdata->packet = s->packet; 266 rdata->packet_length = s->packet_length; 267 memcpy(&(rdata->rbuf), &(s->s3->rbuf), sizeof(SSL3_BUFFER)); 268 memcpy(&(rdata->rrec), &(s->s3->rrec), sizeof(SSL3_RECORD)); 269 270 item->data = rdata; 271 272#ifndef OPENSSL_NO_SCTP 273 /* Store bio_dgram_sctp_rcvinfo struct */ 274 if (BIO_dgram_is_sctp(SSL_get_rbio(s)) && 275 (s->state == SSL3_ST_SR_FINISHED_A 276 || s->state == SSL3_ST_CR_FINISHED_A)) { 277 BIO_ctrl(SSL_get_rbio(s), BIO_CTRL_DGRAM_SCTP_GET_RCVINFO, 278 sizeof(rdata->recordinfo), &rdata->recordinfo); 279 } 280#endif 281 282 s->packet = NULL; 283 s->packet_length = 0; 284 memset(&(s->s3->rbuf), 0, sizeof(SSL3_BUFFER)); 285 memset(&(s->s3->rrec), 0, sizeof(SSL3_RECORD)); 286 287 if (!ssl3_setup_buffers(s)) { 288 SSLerr(SSL_F_DTLS1_BUFFER_RECORD, ERR_R_INTERNAL_ERROR); 289 if (rdata->rbuf.buf != NULL) 290 OPENSSL_free(rdata->rbuf.buf); 291 OPENSSL_free(rdata); 292 pitem_free(item); 293 return (-1); 294 } 295 296 /* insert should not fail, since duplicates are dropped */ 297 if (pqueue_insert(queue->q, item) == NULL) { 298 SSLerr(SSL_F_DTLS1_BUFFER_RECORD, ERR_R_INTERNAL_ERROR); 299 if (rdata->rbuf.buf != NULL) 300 OPENSSL_free(rdata->rbuf.buf); 301 OPENSSL_free(rdata); 302 pitem_free(item); 303 return (-1); 304 } 305 306 return (1); 307} 308 309static int dtls1_retrieve_buffered_record(SSL *s, record_pqueue *queue) 310{ 311 pitem *item; 312 313 item = pqueue_pop(queue->q); 314 if (item) { 315 dtls1_copy_record(s, item); 316 317 OPENSSL_free(item->data); 318 pitem_free(item); 319 320 return (1); 321 } 322 323 return (0); 324} 325 326/* 327 * retrieve a buffered record that belongs to the new epoch, i.e., not 328 * processed yet 329 */ 330#define dtls1_get_unprocessed_record(s) \ 331 dtls1_retrieve_buffered_record((s), \ 332 &((s)->d1->unprocessed_rcds)) 333 334/* 335 * retrieve a buffered record that belongs to the current epoch, ie, 336 * processed 337 */ 338#define dtls1_get_processed_record(s) \ 339 dtls1_retrieve_buffered_record((s), \ 340 &((s)->d1->processed_rcds)) 341 342static int dtls1_process_buffered_records(SSL *s) 343{ 344 pitem *item; 345 SSL3_BUFFER *rb; 346 SSL3_RECORD *rr; 347 DTLS1_BITMAP *bitmap; 348 unsigned int is_next_epoch; 349 int replayok = 1; 350 351 item = pqueue_peek(s->d1->unprocessed_rcds.q); 352 if (item) { 353 /* Check if epoch is current. */ 354 if (s->d1->unprocessed_rcds.epoch != s->d1->r_epoch) 355 return 1; /* Nothing to do. */ 356 357 rr = &s->s3->rrec; 358 rb = &s->s3->rbuf; 359 360 if (rb->left > 0) { 361 /* 362 * We've still got data from the current packet to read. There could 363 * be a record from the new epoch in it - so don't overwrite it 364 * with the unprocessed records yet (we'll do it when we've 365 * finished reading the current packet). 366 */ 367 return 1; 368 } 369 370 371 /* Process all the records. */ 372 while (pqueue_peek(s->d1->unprocessed_rcds.q)) { 373 dtls1_get_unprocessed_record(s); 374 bitmap = dtls1_get_bitmap(s, rr, &is_next_epoch); 375 if (bitmap == NULL) { 376 /* 377 * Should not happen. This will only ever be NULL when the 378 * current record is from a different epoch. But that cannot 379 * be the case because we already checked the epoch above 380 */ 381 SSLerr(SSL_F_DTLS1_PROCESS_BUFFERED_RECORDS, 382 ERR_R_INTERNAL_ERROR); 383 return 0; 384 } 385#ifndef OPENSSL_NO_SCTP 386 /* Only do replay check if no SCTP bio */ 387 if (!BIO_dgram_is_sctp(SSL_get_rbio(s))) 388#endif 389 { 390 /* 391 * Check whether this is a repeat, or aged record. We did this 392 * check once already when we first received the record - but 393 * we might have updated the window since then due to 394 * records we subsequently processed. 395 */ 396 replayok = dtls1_record_replay_check(s, bitmap); 397 } 398 399 if (!replayok || !dtls1_process_record(s, bitmap)) { 400 /* dump this record */ 401 rr->length = 0; 402 s->packet_length = 0; 403 continue; 404 } 405 406 if (dtls1_buffer_record(s, &(s->d1->processed_rcds), 407 s->s3->rrec.seq_num) < 0) 408 return 0; 409 } 410 } 411 412 /* 413 * sync epoch numbers once all the unprocessed records have been 414 * processed 415 */ 416 s->d1->processed_rcds.epoch = s->d1->r_epoch; 417 s->d1->unprocessed_rcds.epoch = s->d1->r_epoch + 1; 418 419 return 1; 420} 421 422#if 0 423 424static int dtls1_get_buffered_record(SSL *s) 425{ 426 pitem *item; 427 PQ_64BIT priority = 428 (((PQ_64BIT) s->d1->handshake_read_seq) << 32) | 429 ((PQ_64BIT) s->d1->r_msg_hdr.frag_off); 430 431 /* if we're not (re)negotiating, nothing buffered */ 432 if (!SSL_in_init(s)) 433 return 0; 434 435 item = pqueue_peek(s->d1->rcvd_records); 436 if (item && item->priority == priority) { 437 /* 438 * Check if we've received the record of interest. It must be a 439 * handshake record, since data records as passed up without 440 * buffering 441 */ 442 DTLS1_RECORD_DATA *rdata; 443 item = pqueue_pop(s->d1->rcvd_records); 444 rdata = (DTLS1_RECORD_DATA *)item->data; 445 446 if (s->s3->rbuf.buf != NULL) 447 OPENSSL_free(s->s3->rbuf.buf); 448 449 s->packet = rdata->packet; 450 s->packet_length = rdata->packet_length; 451 memcpy(&(s->s3->rbuf), &(rdata->rbuf), sizeof(SSL3_BUFFER)); 452 memcpy(&(s->s3->rrec), &(rdata->rrec), sizeof(SSL3_RECORD)); 453 454 OPENSSL_free(item->data); 455 pitem_free(item); 456 457 /* s->d1->next_expected_seq_num++; */ 458 return (1); 459 } 460 461 return 0; 462} 463 464#endif 465 466static int dtls1_process_record(SSL *s, DTLS1_BITMAP *bitmap) 467{ 468 int i, al; 469 int enc_err; 470 SSL_SESSION *sess; 471 SSL3_RECORD *rr; 472 unsigned int mac_size, orig_len; 473 unsigned char md[EVP_MAX_MD_SIZE]; 474 475 rr = &(s->s3->rrec); 476 sess = s->session; 477 478 /* 479 * At this point, s->packet_length == SSL3_RT_HEADER_LNGTH + rr->length, 480 * and we have that many bytes in s->packet 481 */ 482 rr->input = &(s->packet[DTLS1_RT_HEADER_LENGTH]); 483 484 /* 485 * ok, we can now read from 's->packet' data into 'rr' rr->input points 486 * at rr->length bytes, which need to be copied into rr->data by either 487 * the decryption or by the decompression When the data is 'copied' into 488 * the rr->data buffer, rr->input will be pointed at the new buffer 489 */ 490 491 /* 492 * We now have - encrypted [ MAC [ compressed [ plain ] ] ] rr->length 493 * bytes of encrypted compressed stuff. 494 */ 495 496 /* check is not needed I believe */ 497 if (rr->length > SSL3_RT_MAX_ENCRYPTED_LENGTH) { 498 al = SSL_AD_RECORD_OVERFLOW; 499 SSLerr(SSL_F_DTLS1_PROCESS_RECORD, SSL_R_ENCRYPTED_LENGTH_TOO_LONG); 500 goto f_err; 501 } 502 503 /* decrypt in place in 'rr->input' */ 504 rr->data = rr->input; 505 506 enc_err = s->method->ssl3_enc->enc(s, 0); 507 /*- 508 * enc_err is: 509 * 0: (in non-constant time) if the record is publically invalid. 510 * 1: if the padding is valid 511 * -1: if the padding is invalid 512 */ 513 if (enc_err == 0) { 514 /* For DTLS we simply ignore bad packets. */ 515 rr->length = 0; 516 s->packet_length = 0; 517 goto err; 518 } 519#ifdef TLS_DEBUG 520 printf("dec %d\n", rr->length); 521 { 522 unsigned int z; 523 for (z = 0; z < rr->length; z++) 524 printf("%02X%c", rr->data[z], ((z + 1) % 16) ? ' ' : '\n'); 525 } 526 printf("\n"); 527#endif 528 529 /* r->length is now the compressed data plus mac */ 530 if ((sess != NULL) && 531 (s->enc_read_ctx != NULL) && (EVP_MD_CTX_md(s->read_hash) != NULL)) { 532 /* s->read_hash != NULL => mac_size != -1 */ 533 unsigned char *mac = NULL; 534 unsigned char mac_tmp[EVP_MAX_MD_SIZE]; 535 mac_size = EVP_MD_CTX_size(s->read_hash); 536 OPENSSL_assert(mac_size <= EVP_MAX_MD_SIZE); 537 538 /* 539 * kludge: *_cbc_remove_padding passes padding length in rr->type 540 */ 541 orig_len = rr->length + ((unsigned int)rr->type >> 8); 542 543 /* 544 * orig_len is the length of the record before any padding was 545 * removed. This is public information, as is the MAC in use, 546 * therefore we can safely process the record in a different amount 547 * of time if it's too short to possibly contain a MAC. 548 */ 549 if (orig_len < mac_size || 550 /* CBC records must have a padding length byte too. */ 551 (EVP_CIPHER_CTX_mode(s->enc_read_ctx) == EVP_CIPH_CBC_MODE && 552 orig_len < mac_size + 1)) { 553 al = SSL_AD_DECODE_ERROR; 554 SSLerr(SSL_F_DTLS1_PROCESS_RECORD, SSL_R_LENGTH_TOO_SHORT); 555 goto f_err; 556 } 557 558 if (EVP_CIPHER_CTX_mode(s->enc_read_ctx) == EVP_CIPH_CBC_MODE) { 559 /* 560 * We update the length so that the TLS header bytes can be 561 * constructed correctly but we need to extract the MAC in 562 * constant time from within the record, without leaking the 563 * contents of the padding bytes. 564 */ 565 mac = mac_tmp; 566 ssl3_cbc_copy_mac(mac_tmp, rr, mac_size, orig_len); 567 rr->length -= mac_size; 568 } else { 569 /* 570 * In this case there's no padding, so |orig_len| equals 571 * |rec->length| and we checked that there's enough bytes for 572 * |mac_size| above. 573 */ 574 rr->length -= mac_size; 575 mac = &rr->data[rr->length]; 576 } 577 578 i = s->method->ssl3_enc->mac(s, md, 0 /* not send */ ); 579 if (i < 0 || mac == NULL 580 || CRYPTO_memcmp(md, mac, (size_t)mac_size) != 0) 581 enc_err = -1; 582 if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH + mac_size) 583 enc_err = -1; 584 } 585 586 if (enc_err < 0) { 587 /* decryption failed, silently discard message */ 588 rr->length = 0; 589 s->packet_length = 0; 590 goto err; 591 } 592 593 /* r->length is now just compressed */ 594 if (s->expand != NULL) { 595 if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH) { 596 al = SSL_AD_RECORD_OVERFLOW; 597 SSLerr(SSL_F_DTLS1_PROCESS_RECORD, 598 SSL_R_COMPRESSED_LENGTH_TOO_LONG); 599 goto f_err; 600 } 601 if (!ssl3_do_uncompress(s)) { 602 al = SSL_AD_DECOMPRESSION_FAILURE; 603 SSLerr(SSL_F_DTLS1_PROCESS_RECORD, SSL_R_BAD_DECOMPRESSION); 604 goto f_err; 605 } 606 } 607 608 if (rr->length > SSL3_RT_MAX_PLAIN_LENGTH) { 609 al = SSL_AD_RECORD_OVERFLOW; 610 SSLerr(SSL_F_DTLS1_PROCESS_RECORD, SSL_R_DATA_LENGTH_TOO_LONG); 611 goto f_err; 612 } 613 614 rr->off = 0; 615 /*- 616 * So at this point the following is true 617 * ssl->s3->rrec.type is the type of record 618 * ssl->s3->rrec.length == number of bytes in record 619 * ssl->s3->rrec.off == offset to first valid byte 620 * ssl->s3->rrec.data == where to take bytes from, increment 621 * after use :-). 622 */ 623 624 /* we have pulled in a full packet so zero things */ 625 s->packet_length = 0; 626 627 /* Mark receipt of record. */ 628 dtls1_record_bitmap_update(s, bitmap); 629 630 return (1); 631 632 f_err: 633 ssl3_send_alert(s, SSL3_AL_FATAL, al); 634 err: 635 return (0); 636} 637 638/*- 639 * Call this to get a new input record. 640 * It will return <= 0 if more data is needed, normally due to an error 641 * or non-blocking IO. 642 * When it finishes, one packet has been decoded and can be found in 643 * ssl->s3->rrec.type - is the type of record 644 * ssl->s3->rrec.data, - data 645 * ssl->s3->rrec.length, - number of bytes 646 */ 647/* used only by dtls1_read_bytes */ 648int dtls1_get_record(SSL *s) 649{ 650 int ssl_major, ssl_minor; 651 int i, n; 652 SSL3_RECORD *rr; 653 unsigned char *p = NULL; 654 unsigned short version; 655 DTLS1_BITMAP *bitmap; 656 unsigned int is_next_epoch; 657 658 rr = &(s->s3->rrec); 659 660 again: 661 /* 662 * The epoch may have changed. If so, process all the pending records. 663 * This is a non-blocking operation. 664 */ 665 if (!dtls1_process_buffered_records(s)) 666 return -1; 667 668 /* if we're renegotiating, then there may be buffered records */ 669 if (dtls1_get_processed_record(s)) 670 return 1; 671 672 /* get something from the wire */ 673 /* check if we have the header */ 674 if ((s->rstate != SSL_ST_READ_BODY) || 675 (s->packet_length < DTLS1_RT_HEADER_LENGTH)) { 676 n = ssl3_read_n(s, DTLS1_RT_HEADER_LENGTH, s->s3->rbuf.len, 0); 677 /* read timeout is handled by dtls1_read_bytes */ 678 if (n <= 0) 679 return (n); /* error or non-blocking */ 680 681 /* this packet contained a partial record, dump it */ 682 if (s->packet_length != DTLS1_RT_HEADER_LENGTH) { 683 s->packet_length = 0; 684 goto again; 685 } 686 687 s->rstate = SSL_ST_READ_BODY; 688 689 p = s->packet; 690 691 if (s->msg_callback) 692 s->msg_callback(0, 0, SSL3_RT_HEADER, p, DTLS1_RT_HEADER_LENGTH, 693 s, s->msg_callback_arg); 694 695 /* Pull apart the header into the DTLS1_RECORD */ 696 rr->type = *(p++); 697 ssl_major = *(p++); 698 ssl_minor = *(p++); 699 version = (ssl_major << 8) | ssl_minor; 700 701 /* sequence number is 64 bits, with top 2 bytes = epoch */ 702 n2s(p, rr->epoch); 703 704 memcpy(&(s->s3->read_sequence[2]), p, 6); 705 p += 6; 706 707 n2s(p, rr->length); 708 709 /* Lets check version */ 710 if (!s->first_packet) { 711 if (version != s->version) { 712 /* unexpected version, silently discard */ 713 rr->length = 0; 714 s->packet_length = 0; 715 goto again; 716 } 717 } 718 719 if ((version & 0xff00) != (s->version & 0xff00)) { 720 /* wrong version, silently discard record */ 721 rr->length = 0; 722 s->packet_length = 0; 723 goto again; 724 } 725 726 if (rr->length > SSL3_RT_MAX_ENCRYPTED_LENGTH) { 727 /* record too long, silently discard it */ 728 rr->length = 0; 729 s->packet_length = 0; 730 goto again; 731 } 732 733 /* now s->rstate == SSL_ST_READ_BODY */ 734 } 735 736 /* s->rstate == SSL_ST_READ_BODY, get and decode the data */ 737 738 if (rr->length > s->packet_length - DTLS1_RT_HEADER_LENGTH) { 739 /* now s->packet_length == DTLS1_RT_HEADER_LENGTH */ 740 i = rr->length; 741 n = ssl3_read_n(s, i, i, 1); 742 /* this packet contained a partial record, dump it */ 743 if (n != i) { 744 rr->length = 0; 745 s->packet_length = 0; 746 goto again; 747 } 748 749 /* 750 * now n == rr->length, and s->packet_length == 751 * DTLS1_RT_HEADER_LENGTH + rr->length 752 */ 753 } 754 s->rstate = SSL_ST_READ_HEADER; /* set state for later operations */ 755 756 /* match epochs. NULL means the packet is dropped on the floor */ 757 bitmap = dtls1_get_bitmap(s, rr, &is_next_epoch); 758 if (bitmap == NULL) { 759 rr->length = 0; 760 s->packet_length = 0; /* dump this record */ 761 goto again; /* get another record */ 762 } 763#ifndef OPENSSL_NO_SCTP 764 /* Only do replay check if no SCTP bio */ 765 if (!BIO_dgram_is_sctp(SSL_get_rbio(s))) { 766#endif 767 /* 768 * Check whether this is a repeat, or aged record. Don't check if 769 * we're listening and this message is a ClientHello. They can look 770 * as if they're replayed, since they arrive from different 771 * connections and would be dropped unnecessarily. 772 */ 773 if (!(s->d1->listen && rr->type == SSL3_RT_HANDSHAKE && 774 s->packet_length > DTLS1_RT_HEADER_LENGTH && 775 s->packet[DTLS1_RT_HEADER_LENGTH] == SSL3_MT_CLIENT_HELLO) && 776 !dtls1_record_replay_check(s, bitmap)) { 777 rr->length = 0; 778 s->packet_length = 0; /* dump this record */ 779 goto again; /* get another record */ 780 } 781#ifndef OPENSSL_NO_SCTP 782 } 783#endif 784 785 /* just read a 0 length packet */ 786 if (rr->length == 0) 787 goto again; 788 789 /* 790 * If this record is from the next epoch (either HM or ALERT), and a 791 * handshake is currently in progress, buffer it since it cannot be 792 * processed at this time. However, do not buffer anything while 793 * listening. 794 */ 795 if (is_next_epoch) { 796 if ((SSL_in_init(s) || s->in_handshake) && !s->d1->listen) { 797 if (dtls1_buffer_record 798 (s, &(s->d1->unprocessed_rcds), rr->seq_num) < 0) 799 return -1; 800 } 801 rr->length = 0; 802 s->packet_length = 0; 803 goto again; 804 } 805 806 if (!dtls1_process_record(s, bitmap)) { 807 rr->length = 0; 808 s->packet_length = 0; /* dump this record */ 809 goto again; /* get another record */ 810 } 811 812 return (1); 813 814} 815 816/*- 817 * Return up to 'len' payload bytes received in 'type' records. 818 * 'type' is one of the following: 819 * 820 * - SSL3_RT_HANDSHAKE (when ssl3_get_message calls us) 821 * - SSL3_RT_APPLICATION_DATA (when ssl3_read calls us) 822 * - 0 (during a shutdown, no data has to be returned) 823 * 824 * If we don't have stored data to work from, read a SSL/TLS record first 825 * (possibly multiple records if we still don't have anything to return). 826 * 827 * This function must handle any surprises the peer may have for us, such as 828 * Alert records (e.g. close_notify), ChangeCipherSpec records (not really 829 * a surprise, but handled as if it were), or renegotiation requests. 830 * Also if record payloads contain fragments too small to process, we store 831 * them until there is enough for the respective protocol (the record protocol 832 * may use arbitrary fragmentation and even interleaving): 833 * Change cipher spec protocol 834 * just 1 byte needed, no need for keeping anything stored 835 * Alert protocol 836 * 2 bytes needed (AlertLevel, AlertDescription) 837 * Handshake protocol 838 * 4 bytes needed (HandshakeType, uint24 length) -- we just have 839 * to detect unexpected Client Hello and Hello Request messages 840 * here, anything else is handled by higher layers 841 * Application data protocol 842 * none of our business 843 */ 844int dtls1_read_bytes(SSL *s, int type, unsigned char *buf, int len, int peek) 845{ 846 int al, i, j, ret; 847 unsigned int n; 848 SSL3_RECORD *rr; 849 void (*cb) (const SSL *ssl, int type2, int val) = NULL; 850 851 if (s->s3->rbuf.buf == NULL) /* Not initialized yet */ 852 if (!ssl3_setup_buffers(s)) 853 return (-1); 854 855 /* XXX: check what the second '&& type' is about */ 856 if ((type && (type != SSL3_RT_APPLICATION_DATA) && 857 (type != SSL3_RT_HANDSHAKE) && type) || 858 (peek && (type != SSL3_RT_APPLICATION_DATA))) { 859 SSLerr(SSL_F_DTLS1_READ_BYTES, ERR_R_INTERNAL_ERROR); 860 return -1; 861 } 862 863 /* 864 * check whether there's a handshake message (client hello?) waiting 865 */ 866 if ((ret = have_handshake_fragment(s, type, buf, len, peek))) 867 return ret; 868 869 /* 870 * Now s->d1->handshake_fragment_len == 0 if type == SSL3_RT_HANDSHAKE. 871 */ 872 873#ifndef OPENSSL_NO_SCTP 874 /* 875 * Continue handshake if it had to be interrupted to read app data with 876 * SCTP. 877 */ 878 if ((!s->in_handshake && SSL_in_init(s)) || 879 (BIO_dgram_is_sctp(SSL_get_rbio(s)) && 880 (s->state == DTLS1_SCTP_ST_SR_READ_SOCK 881 || s->state == DTLS1_SCTP_ST_CR_READ_SOCK) 882 && s->s3->in_read_app_data != 2)) 883#else 884 if (!s->in_handshake && SSL_in_init(s)) 885#endif 886 { 887 /* type == SSL3_RT_APPLICATION_DATA */ 888 i = s->handshake_func(s); 889 if (i < 0) 890 return (i); 891 if (i == 0) { 892 SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_R_SSL_HANDSHAKE_FAILURE); 893 return (-1); 894 } 895 } 896 897 start: 898 s->rwstate = SSL_NOTHING; 899 900 /*- 901 * s->s3->rrec.type - is the type of record 902 * s->s3->rrec.data, - data 903 * s->s3->rrec.off, - offset into 'data' for next read 904 * s->s3->rrec.length, - number of bytes. 905 */ 906 rr = &(s->s3->rrec); 907 908 /* 909 * We are not handshaking and have no data yet, so process data buffered 910 * during the last handshake in advance, if any. 911 */ 912 if (s->state == SSL_ST_OK && rr->length == 0) { 913 pitem *item; 914 item = pqueue_pop(s->d1->buffered_app_data.q); 915 if (item) { 916#ifndef OPENSSL_NO_SCTP 917 /* Restore bio_dgram_sctp_rcvinfo struct */ 918 if (BIO_dgram_is_sctp(SSL_get_rbio(s))) { 919 DTLS1_RECORD_DATA *rdata = (DTLS1_RECORD_DATA *)item->data; 920 BIO_ctrl(SSL_get_rbio(s), BIO_CTRL_DGRAM_SCTP_SET_RCVINFO, 921 sizeof(rdata->recordinfo), &rdata->recordinfo); 922 } 923#endif 924 925 dtls1_copy_record(s, item); 926 927 OPENSSL_free(item->data); 928 pitem_free(item); 929 } 930 } 931 932 /* Check for timeout */ 933 if (dtls1_handle_timeout(s) > 0) 934 goto start; 935 936 /* get new packet if necessary */ 937 if ((rr->length == 0) || (s->rstate == SSL_ST_READ_BODY)) { 938 ret = dtls1_get_record(s); 939 if (ret <= 0) { 940 ret = dtls1_read_failed(s, ret); 941 /* anything other than a timeout is an error */ 942 if (ret <= 0) 943 return (ret); 944 else 945 goto start; 946 } 947 } 948 949 if (s->d1->listen && rr->type != SSL3_RT_HANDSHAKE) { 950 rr->length = 0; 951 goto start; 952 } 953 954 /* 955 * Reset the count of consecutive warning alerts if we've got a non-empty 956 * record that isn't an alert. 957 */ 958 if (rr->type != SSL3_RT_ALERT && rr->length != 0) 959 s->cert->alert_count = 0; 960 961 /* we now have a packet which can be read and processed */ 962 963 if (s->s3->change_cipher_spec /* set when we receive ChangeCipherSpec, 964 * reset by ssl3_get_finished */ 965 && (rr->type != SSL3_RT_HANDSHAKE)) { 966 /* 967 * We now have application data between CCS and Finished. Most likely 968 * the packets were reordered on their way, so buffer the application 969 * data for later processing rather than dropping the connection. 970 */ 971 if (dtls1_buffer_record(s, &(s->d1->buffered_app_data), rr->seq_num) < 972 0) { 973 SSLerr(SSL_F_DTLS1_READ_BYTES, ERR_R_INTERNAL_ERROR); 974 return -1; 975 } 976 rr->length = 0; 977 goto start; 978 } 979 980 /* 981 * If the other end has shut down, throw anything we read away (even in 982 * 'peek' mode) 983 */ 984 if (s->shutdown & SSL_RECEIVED_SHUTDOWN) { 985 rr->length = 0; 986 s->rwstate = SSL_NOTHING; 987 return (0); 988 } 989 990 if (type == rr->type) { /* SSL3_RT_APPLICATION_DATA or 991 * SSL3_RT_HANDSHAKE */ 992 /* 993 * make sure that we are not getting application data when we are 994 * doing a handshake for the first time 995 */ 996 if (SSL_in_init(s) && (type == SSL3_RT_APPLICATION_DATA) && 997 (s->enc_read_ctx == NULL)) { 998 al = SSL_AD_UNEXPECTED_MESSAGE; 999 SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_R_APP_DATA_IN_HANDSHAKE); 1000 goto f_err; 1001 } 1002 1003 if (len <= 0) 1004 return (len); 1005 1006 if ((unsigned int)len > rr->length) 1007 n = rr->length; 1008 else 1009 n = (unsigned int)len; 1010 1011 memcpy(buf, &(rr->data[rr->off]), n); 1012 if (!peek) { 1013 rr->length -= n; 1014 rr->off += n; 1015 if (rr->length == 0) { 1016 s->rstate = SSL_ST_READ_HEADER; 1017 rr->off = 0; 1018 } 1019 } 1020#ifndef OPENSSL_NO_SCTP 1021 /* 1022 * We were about to renegotiate but had to read belated application 1023 * data first, so retry. 1024 */ 1025 if (BIO_dgram_is_sctp(SSL_get_rbio(s)) && 1026 rr->type == SSL3_RT_APPLICATION_DATA && 1027 (s->state == DTLS1_SCTP_ST_SR_READ_SOCK 1028 || s->state == DTLS1_SCTP_ST_CR_READ_SOCK)) { 1029 s->rwstate = SSL_READING; 1030 BIO_clear_retry_flags(SSL_get_rbio(s)); 1031 BIO_set_retry_read(SSL_get_rbio(s)); 1032 } 1033 1034 /* 1035 * We might had to delay a close_notify alert because of reordered 1036 * app data. If there was an alert and there is no message to read 1037 * anymore, finally set shutdown. 1038 */ 1039 if (BIO_dgram_is_sctp(SSL_get_rbio(s)) && 1040 s->d1->shutdown_received 1041 && !BIO_dgram_sctp_msg_waiting(SSL_get_rbio(s))) { 1042 s->shutdown |= SSL_RECEIVED_SHUTDOWN; 1043 return (0); 1044 } 1045#endif 1046 return (n); 1047 } 1048 1049 /* 1050 * If we get here, then type != rr->type; if we have a handshake message, 1051 * then it was unexpected (Hello Request or Client Hello). 1052 */ 1053 1054 /* 1055 * In case of record types for which we have 'fragment' storage, fill 1056 * that so that we can process the data at a fixed place. 1057 */ 1058 { 1059 unsigned int k, dest_maxlen = 0; 1060 unsigned char *dest = NULL; 1061 unsigned int *dest_len = NULL; 1062 1063 if (rr->type == SSL3_RT_HANDSHAKE) { 1064 dest_maxlen = sizeof s->d1->handshake_fragment; 1065 dest = s->d1->handshake_fragment; 1066 dest_len = &s->d1->handshake_fragment_len; 1067 } else if (rr->type == SSL3_RT_ALERT) { 1068 dest_maxlen = sizeof(s->d1->alert_fragment); 1069 dest = s->d1->alert_fragment; 1070 dest_len = &s->d1->alert_fragment_len; 1071 } 1072#ifndef OPENSSL_NO_HEARTBEATS 1073 else if (rr->type == TLS1_RT_HEARTBEAT) { 1074 dtls1_process_heartbeat(s); 1075 1076 /* Exit and notify application to read again */ 1077 rr->length = 0; 1078 s->rwstate = SSL_READING; 1079 BIO_clear_retry_flags(SSL_get_rbio(s)); 1080 BIO_set_retry_read(SSL_get_rbio(s)); 1081 return (-1); 1082 } 1083#endif 1084 /* else it's a CCS message, or application data or wrong */ 1085 else if (rr->type != SSL3_RT_CHANGE_CIPHER_SPEC) { 1086 /* 1087 * Application data while renegotiating is allowed. Try again 1088 * reading. 1089 */ 1090 if (rr->type == SSL3_RT_APPLICATION_DATA) { 1091 BIO *bio; 1092 s->s3->in_read_app_data = 2; 1093 bio = SSL_get_rbio(s); 1094 s->rwstate = SSL_READING; 1095 BIO_clear_retry_flags(bio); 1096 BIO_set_retry_read(bio); 1097 return (-1); 1098 } 1099 1100 /* Not certain if this is the right error handling */ 1101 al = SSL_AD_UNEXPECTED_MESSAGE; 1102 SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_R_UNEXPECTED_RECORD); 1103 goto f_err; 1104 } 1105 1106 if (dest_maxlen > 0) { 1107 /* 1108 * XDTLS: In a pathalogical case, the Client Hello may be 1109 * fragmented--don't always expect dest_maxlen bytes 1110 */ 1111 if (rr->length < dest_maxlen) { 1112#ifdef DTLS1_AD_MISSING_HANDSHAKE_MESSAGE 1113 /* 1114 * for normal alerts rr->length is 2, while 1115 * dest_maxlen is 7 if we were to handle this 1116 * non-existing alert... 1117 */ 1118 FIX ME 1119#endif 1120 s->rstate = SSL_ST_READ_HEADER; 1121 rr->length = 0; 1122 goto start; 1123 } 1124 1125 /* now move 'n' bytes: */ 1126 for (k = 0; k < dest_maxlen; k++) { 1127 dest[k] = rr->data[rr->off++]; 1128 rr->length--; 1129 } 1130 *dest_len = dest_maxlen; 1131 } 1132 } 1133 1134 /*- 1135 * s->d1->handshake_fragment_len == 12 iff rr->type == SSL3_RT_HANDSHAKE; 1136 * s->d1->alert_fragment_len == 7 iff rr->type == SSL3_RT_ALERT. 1137 * (Possibly rr is 'empty' now, i.e. rr->length may be 0.) 1138 */ 1139 1140 /* If we are a client, check for an incoming 'Hello Request': */ 1141 if ((!s->server) && 1142 (s->d1->handshake_fragment_len >= DTLS1_HM_HEADER_LENGTH) && 1143 (s->d1->handshake_fragment[0] == SSL3_MT_HELLO_REQUEST) && 1144 (s->session != NULL) && (s->session->cipher != NULL)) { 1145 s->d1->handshake_fragment_len = 0; 1146 1147 if ((s->d1->handshake_fragment[1] != 0) || 1148 (s->d1->handshake_fragment[2] != 0) || 1149 (s->d1->handshake_fragment[3] != 0)) { 1150 al = SSL_AD_DECODE_ERROR; 1151 SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_R_BAD_HELLO_REQUEST); 1152 goto f_err; 1153 } 1154 1155 /* 1156 * no need to check sequence number on HELLO REQUEST messages 1157 */ 1158 1159 if (s->msg_callback) 1160 s->msg_callback(0, s->version, SSL3_RT_HANDSHAKE, 1161 s->d1->handshake_fragment, 4, s, 1162 s->msg_callback_arg); 1163 1164 if (SSL_is_init_finished(s) && 1165 !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS) && 1166 !s->s3->renegotiate) { 1167 s->d1->handshake_read_seq++; 1168 s->new_session = 1; 1169 ssl3_renegotiate(s); 1170 if (ssl3_renegotiate_check(s)) { 1171 i = s->handshake_func(s); 1172 if (i < 0) 1173 return (i); 1174 if (i == 0) { 1175 SSLerr(SSL_F_DTLS1_READ_BYTES, 1176 SSL_R_SSL_HANDSHAKE_FAILURE); 1177 return (-1); 1178 } 1179 1180 if (!(s->mode & SSL_MODE_AUTO_RETRY)) { 1181 if (s->s3->rbuf.left == 0) { /* no read-ahead left? */ 1182 BIO *bio; 1183 /* 1184 * In the case where we try to read application data, 1185 * but we trigger an SSL handshake, we return -1 with 1186 * the retry option set. Otherwise renegotiation may 1187 * cause nasty problems in the blocking world 1188 */ 1189 s->rwstate = SSL_READING; 1190 bio = SSL_get_rbio(s); 1191 BIO_clear_retry_flags(bio); 1192 BIO_set_retry_read(bio); 1193 return (-1); 1194 } 1195 } 1196 } 1197 } 1198 /* 1199 * we either finished a handshake or ignored the request, now try 1200 * again to obtain the (application) data we were asked for 1201 */ 1202 goto start; 1203 } 1204 1205 if (s->d1->alert_fragment_len >= DTLS1_AL_HEADER_LENGTH) { 1206 int alert_level = s->d1->alert_fragment[0]; 1207 int alert_descr = s->d1->alert_fragment[1]; 1208 1209 s->d1->alert_fragment_len = 0; 1210 1211 if (s->msg_callback) 1212 s->msg_callback(0, s->version, SSL3_RT_ALERT, 1213 s->d1->alert_fragment, 2, s, s->msg_callback_arg); 1214 1215 if (s->info_callback != NULL) 1216 cb = s->info_callback; 1217 else if (s->ctx->info_callback != NULL) 1218 cb = s->ctx->info_callback; 1219 1220 if (cb != NULL) { 1221 j = (alert_level << 8) | alert_descr; 1222 cb(s, SSL_CB_READ_ALERT, j); 1223 } 1224 1225 if (alert_level == SSL3_AL_WARNING) { 1226 s->s3->warn_alert = alert_descr; 1227 1228 s->cert->alert_count++; 1229 if (s->cert->alert_count == MAX_WARN_ALERT_COUNT) { 1230 al = SSL_AD_UNEXPECTED_MESSAGE; 1231 SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_R_TOO_MANY_WARN_ALERTS); 1232 goto f_err; 1233 } 1234 1235 if (alert_descr == SSL_AD_CLOSE_NOTIFY) { 1236#ifndef OPENSSL_NO_SCTP 1237 /* 1238 * With SCTP and streams the socket may deliver app data 1239 * after a close_notify alert. We have to check this first so 1240 * that nothing gets discarded. 1241 */ 1242 if (BIO_dgram_is_sctp(SSL_get_rbio(s)) && 1243 BIO_dgram_sctp_msg_waiting(SSL_get_rbio(s))) { 1244 s->d1->shutdown_received = 1; 1245 s->rwstate = SSL_READING; 1246 BIO_clear_retry_flags(SSL_get_rbio(s)); 1247 BIO_set_retry_read(SSL_get_rbio(s)); 1248 return -1; 1249 } 1250#endif 1251 s->shutdown |= SSL_RECEIVED_SHUTDOWN; 1252 return (0); 1253 } 1254#if 0 1255 /* XXX: this is a possible improvement in the future */ 1256 /* now check if it's a missing record */ 1257 if (alert_descr == DTLS1_AD_MISSING_HANDSHAKE_MESSAGE) { 1258 unsigned short seq; 1259 unsigned int frag_off; 1260 unsigned char *p = &(s->d1->alert_fragment[2]); 1261 1262 n2s(p, seq); 1263 n2l3(p, frag_off); 1264 1265 dtls1_retransmit_message(s, 1266 dtls1_get_queue_priority 1267 (frag->msg_header.seq, 0), frag_off, 1268 &found); 1269 if (!found && SSL_in_init(s)) { 1270 /* 1271 * fprintf( stderr,"in init = %d\n", SSL_in_init(s)); 1272 */ 1273 /* 1274 * requested a message not yet sent, send an alert 1275 * ourselves 1276 */ 1277 ssl3_send_alert(s, SSL3_AL_WARNING, 1278 DTLS1_AD_MISSING_HANDSHAKE_MESSAGE); 1279 } 1280 } 1281#endif 1282 } else if (alert_level == SSL3_AL_FATAL) { 1283 char tmp[16]; 1284 1285 s->rwstate = SSL_NOTHING; 1286 s->s3->fatal_alert = alert_descr; 1287 SSLerr(SSL_F_DTLS1_READ_BYTES, 1288 SSL_AD_REASON_OFFSET + alert_descr); 1289 BIO_snprintf(tmp, sizeof tmp, "%d", alert_descr); 1290 ERR_add_error_data(2, "SSL alert number ", tmp); 1291 s->shutdown |= SSL_RECEIVED_SHUTDOWN; 1292 SSL_CTX_remove_session(s->session_ctx, s->session); 1293 return (0); 1294 } else { 1295 al = SSL_AD_ILLEGAL_PARAMETER; 1296 SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_R_UNKNOWN_ALERT_TYPE); 1297 goto f_err; 1298 } 1299 1300 goto start; 1301 } 1302 1303 if (s->shutdown & SSL_SENT_SHUTDOWN) { /* but we have not received a 1304 * shutdown */ 1305 s->rwstate = SSL_NOTHING; 1306 rr->length = 0; 1307 return (0); 1308 } 1309 1310 if (rr->type == SSL3_RT_CHANGE_CIPHER_SPEC) { 1311 struct ccs_header_st ccs_hdr; 1312 unsigned int ccs_hdr_len = DTLS1_CCS_HEADER_LENGTH; 1313 1314 dtls1_get_ccs_header(rr->data, &ccs_hdr); 1315 1316 if (s->version == DTLS1_BAD_VER) 1317 ccs_hdr_len = 3; 1318 1319 /* 1320 * 'Change Cipher Spec' is just a single byte, so we know exactly 1321 * what the record payload has to look like 1322 */ 1323 /* XDTLS: check that epoch is consistent */ 1324 if ((rr->length != ccs_hdr_len) || 1325 (rr->off != 0) || (rr->data[0] != SSL3_MT_CCS)) { 1326 i = SSL_AD_ILLEGAL_PARAMETER; 1327 SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_R_BAD_CHANGE_CIPHER_SPEC); 1328 goto err; 1329 } 1330 1331 rr->length = 0; 1332 1333 if (s->msg_callback) 1334 s->msg_callback(0, s->version, SSL3_RT_CHANGE_CIPHER_SPEC, 1335 rr->data, 1, s, s->msg_callback_arg); 1336 1337 /* 1338 * We can't process a CCS now, because previous handshake messages 1339 * are still missing, so just drop it. 1340 */ 1341 if (!s->d1->change_cipher_spec_ok) { 1342 goto start; 1343 } 1344 1345 s->d1->change_cipher_spec_ok = 0; 1346 1347 s->s3->change_cipher_spec = 1; 1348 if (!ssl3_do_change_cipher_spec(s)) 1349 goto err; 1350 1351 /* do this whenever CCS is processed */ 1352 dtls1_reset_seq_numbers(s, SSL3_CC_READ); 1353 1354 if (s->version == DTLS1_BAD_VER) 1355 s->d1->handshake_read_seq++; 1356 1357#ifndef OPENSSL_NO_SCTP 1358 /* 1359 * Remember that a CCS has been received, so that an old key of 1360 * SCTP-Auth can be deleted when a CCS is sent. Will be ignored if no 1361 * SCTP is used 1362 */ 1363 BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_AUTH_CCS_RCVD, 1, NULL); 1364#endif 1365 1366 goto start; 1367 } 1368 1369 /* 1370 * Unexpected handshake message (Client Hello, or protocol violation) 1371 */ 1372 if ((s->d1->handshake_fragment_len >= DTLS1_HM_HEADER_LENGTH) && 1373 !s->in_handshake) { 1374 struct hm_header_st msg_hdr; 1375 1376 /* this may just be a stale retransmit */ 1377 dtls1_get_message_header(rr->data, &msg_hdr); 1378 if (rr->epoch != s->d1->r_epoch) { 1379 rr->length = 0; 1380 goto start; 1381 } 1382 1383 /* 1384 * If we are server, we may have a repeated FINISHED of the client 1385 * here, then retransmit our CCS and FINISHED. 1386 */ 1387 if (msg_hdr.type == SSL3_MT_FINISHED) { 1388 if (dtls1_check_timeout_num(s) < 0) 1389 return -1; 1390 1391 dtls1_retransmit_buffered_messages(s); 1392 rr->length = 0; 1393 goto start; 1394 } 1395 1396 if (((s->state & SSL_ST_MASK) == SSL_ST_OK) && 1397 !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS)) { 1398#if 0 /* worked only because C operator preferences 1399 * are not as expected (and because this is 1400 * not really needed for clients except for 1401 * detecting protocol violations): */ 1402 s->state = SSL_ST_BEFORE | (s->server) 1403 ? SSL_ST_ACCEPT : SSL_ST_CONNECT; 1404#else 1405 s->state = s->server ? SSL_ST_ACCEPT : SSL_ST_CONNECT; 1406#endif 1407 s->renegotiate = 1; 1408 s->new_session = 1; 1409 } 1410 i = s->handshake_func(s); 1411 if (i < 0) 1412 return (i); 1413 if (i == 0) { 1414 SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_R_SSL_HANDSHAKE_FAILURE); 1415 return (-1); 1416 } 1417 1418 if (!(s->mode & SSL_MODE_AUTO_RETRY)) { 1419 if (s->s3->rbuf.left == 0) { /* no read-ahead left? */ 1420 BIO *bio; 1421 /* 1422 * In the case where we try to read application data, but we 1423 * trigger an SSL handshake, we return -1 with the retry 1424 * option set. Otherwise renegotiation may cause nasty 1425 * problems in the blocking world 1426 */ 1427 s->rwstate = SSL_READING; 1428 bio = SSL_get_rbio(s); 1429 BIO_clear_retry_flags(bio); 1430 BIO_set_retry_read(bio); 1431 return (-1); 1432 } 1433 } 1434 goto start; 1435 } 1436 1437 switch (rr->type) { 1438 default: 1439#ifndef OPENSSL_NO_TLS 1440 /* TLS just ignores unknown message types */ 1441 if (s->version == TLS1_VERSION) { 1442 rr->length = 0; 1443 goto start; 1444 } 1445#endif 1446 al = SSL_AD_UNEXPECTED_MESSAGE; 1447 SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_R_UNEXPECTED_RECORD); 1448 goto f_err; 1449 case SSL3_RT_CHANGE_CIPHER_SPEC: 1450 case SSL3_RT_ALERT: 1451 case SSL3_RT_HANDSHAKE: 1452 /* 1453 * we already handled all of these, with the possible exception of 1454 * SSL3_RT_HANDSHAKE when s->in_handshake is set, but that should not 1455 * happen when type != rr->type 1456 */ 1457 al = SSL_AD_UNEXPECTED_MESSAGE; 1458 SSLerr(SSL_F_DTLS1_READ_BYTES, ERR_R_INTERNAL_ERROR); 1459 goto f_err; 1460 case SSL3_RT_APPLICATION_DATA: 1461 /* 1462 * At this point, we were expecting handshake data, but have 1463 * application data. If the library was running inside ssl3_read() 1464 * (i.e. in_read_app_data is set) and it makes sense to read 1465 * application data at this point (session renegotiation not yet 1466 * started), we will indulge it. 1467 */ 1468 if (s->s3->in_read_app_data && 1469 (s->s3->total_renegotiations != 0) && 1470 (((s->state & SSL_ST_CONNECT) && 1471 (s->state >= SSL3_ST_CW_CLNT_HELLO_A) && 1472 (s->state <= SSL3_ST_CR_SRVR_HELLO_A) 1473 ) || ((s->state & SSL_ST_ACCEPT) && 1474 (s->state <= SSL3_ST_SW_HELLO_REQ_A) && 1475 (s->state >= SSL3_ST_SR_CLNT_HELLO_A) 1476 ) 1477 )) { 1478 s->s3->in_read_app_data = 2; 1479 return (-1); 1480 } else { 1481 al = SSL_AD_UNEXPECTED_MESSAGE; 1482 SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_R_UNEXPECTED_RECORD); 1483 goto f_err; 1484 } 1485 } 1486 /* not reached */ 1487 1488 f_err: 1489 ssl3_send_alert(s, SSL3_AL_FATAL, al); 1490 err: 1491 return (-1); 1492} 1493 1494int dtls1_write_app_data_bytes(SSL *s, int type, const void *buf_, int len) 1495{ 1496 int i; 1497 1498#ifndef OPENSSL_NO_SCTP 1499 /* 1500 * Check if we have to continue an interrupted handshake for reading 1501 * belated app data with SCTP. 1502 */ 1503 if ((SSL_in_init(s) && !s->in_handshake) || 1504 (BIO_dgram_is_sctp(SSL_get_wbio(s)) && 1505 (s->state == DTLS1_SCTP_ST_SR_READ_SOCK 1506 || s->state == DTLS1_SCTP_ST_CR_READ_SOCK))) 1507#else 1508 if (SSL_in_init(s) && !s->in_handshake) 1509#endif 1510 { 1511 i = s->handshake_func(s); 1512 if (i < 0) 1513 return (i); 1514 if (i == 0) { 1515 SSLerr(SSL_F_DTLS1_WRITE_APP_DATA_BYTES, 1516 SSL_R_SSL_HANDSHAKE_FAILURE); 1517 return -1; 1518 } 1519 } 1520 1521 if (len > SSL3_RT_MAX_PLAIN_LENGTH) { 1522 SSLerr(SSL_F_DTLS1_WRITE_APP_DATA_BYTES, SSL_R_DTLS_MESSAGE_TOO_BIG); 1523 return -1; 1524 } 1525 1526 i = dtls1_write_bytes(s, type, buf_, len); 1527 return i; 1528} 1529 1530 /* 1531 * this only happens when a client hello is received and a handshake 1532 * is started. 1533 */ 1534static int 1535have_handshake_fragment(SSL *s, int type, unsigned char *buf, 1536 int len, int peek) 1537{ 1538 1539 if ((type == SSL3_RT_HANDSHAKE) && (s->d1->handshake_fragment_len > 0)) 1540 /* (partially) satisfy request from storage */ 1541 { 1542 unsigned char *src = s->d1->handshake_fragment; 1543 unsigned char *dst = buf; 1544 unsigned int k, n; 1545 1546 /* peek == 0 */ 1547 n = 0; 1548 while ((len > 0) && (s->d1->handshake_fragment_len > 0)) { 1549 *dst++ = *src++; 1550 len--; 1551 s->d1->handshake_fragment_len--; 1552 n++; 1553 } 1554 /* move any remaining fragment bytes: */ 1555 for (k = 0; k < s->d1->handshake_fragment_len; k++) 1556 s->d1->handshake_fragment[k] = *src++; 1557 return n; 1558 } 1559 1560 return 0; 1561} 1562 1563/* 1564 * Call this to write data in records of type 'type' It will return <= 0 if 1565 * not all data has been sent or non-blocking IO. 1566 */ 1567int dtls1_write_bytes(SSL *s, int type, const void *buf, int len) 1568{ 1569 int i; 1570 1571 OPENSSL_assert(len <= SSL3_RT_MAX_PLAIN_LENGTH); 1572 s->rwstate = SSL_NOTHING; 1573 i = do_dtls1_write(s, type, buf, len, 0); 1574 return i; 1575} 1576 1577int do_dtls1_write(SSL *s, int type, const unsigned char *buf, 1578 unsigned int len, int create_empty_fragment) 1579{ 1580 unsigned char *p, *pseq; 1581 int i, mac_size, clear = 0; 1582 int prefix_len = 0; 1583 int eivlen; 1584 SSL3_RECORD *wr; 1585 SSL3_BUFFER *wb; 1586 SSL_SESSION *sess; 1587 1588 /* 1589 * first check if there is a SSL3_BUFFER still being written out. This 1590 * will happen with non blocking IO 1591 */ 1592 if (s->s3->wbuf.left != 0) { 1593 OPENSSL_assert(0); /* XDTLS: want to see if we ever get here */ 1594 return (ssl3_write_pending(s, type, buf, len)); 1595 } 1596 1597 /* If we have an alert to send, lets send it */ 1598 if (s->s3->alert_dispatch) { 1599 i = s->method->ssl_dispatch_alert(s); 1600 if (i <= 0) 1601 return (i); 1602 /* if it went, fall through and send more stuff */ 1603 } 1604 1605 if (len == 0 && !create_empty_fragment) 1606 return 0; 1607 1608 wr = &(s->s3->wrec); 1609 wb = &(s->s3->wbuf); 1610 sess = s->session; 1611 1612 if ((sess == NULL) || 1613 (s->enc_write_ctx == NULL) || (EVP_MD_CTX_md(s->write_hash) == NULL)) 1614 clear = 1; 1615 1616 if (clear) 1617 mac_size = 0; 1618 else { 1619 mac_size = EVP_MD_CTX_size(s->write_hash); 1620 if (mac_size < 0) 1621 goto err; 1622 } 1623 1624 /* DTLS implements explicit IV, so no need for empty fragments */ 1625#if 0 1626 /* 1627 * 'create_empty_fragment' is true only when this function calls itself 1628 */ 1629 if (!clear && !create_empty_fragment && !s->s3->empty_fragment_done 1630 && SSL_version(s) != DTLS1_VERSION && SSL_version(s) != DTLS1_BAD_VER) 1631 { 1632 /* 1633 * countermeasure against known-IV weakness in CBC ciphersuites (see 1634 * http://www.openssl.org/~bodo/tls-cbc.txt) 1635 */ 1636 1637 if (s->s3->need_empty_fragments && type == SSL3_RT_APPLICATION_DATA) { 1638 /* 1639 * recursive function call with 'create_empty_fragment' set; this 1640 * prepares and buffers the data for an empty fragment (these 1641 * 'prefix_len' bytes are sent out later together with the actual 1642 * payload) 1643 */ 1644 prefix_len = s->method->do_ssl_write(s, type, buf, 0, 1); 1645 if (prefix_len <= 0) 1646 goto err; 1647 1648 if (s->s3->wbuf.len < 1649 (size_t)prefix_len + SSL3_RT_MAX_PACKET_SIZE) { 1650 /* insufficient space */ 1651 SSLerr(SSL_F_DO_DTLS1_WRITE, ERR_R_INTERNAL_ERROR); 1652 goto err; 1653 } 1654 } 1655 1656 s->s3->empty_fragment_done = 1; 1657 } 1658#endif 1659 p = wb->buf + prefix_len; 1660 1661 /* write the header */ 1662 1663 *(p++) = type & 0xff; 1664 wr->type = type; 1665 /* 1666 * Special case: for hello verify request, client version 1.0 and we 1667 * haven't decided which version to use yet send back using version 1.0 1668 * header: otherwise some clients will ignore it. 1669 */ 1670 if (s->method->version == DTLS_ANY_VERSION) { 1671 *(p++) = DTLS1_VERSION >> 8; 1672 *(p++) = DTLS1_VERSION & 0xff; 1673 } else { 1674 *(p++) = s->version >> 8; 1675 *(p++) = s->version & 0xff; 1676 } 1677 1678 /* field where we are to write out packet epoch, seq num and len */ 1679 pseq = p; 1680 p += 10; 1681 1682 /* Explicit IV length, block ciphers appropriate version flag */ 1683 if (s->enc_write_ctx) { 1684 int mode = EVP_CIPHER_CTX_mode(s->enc_write_ctx); 1685 if (mode == EVP_CIPH_CBC_MODE) { 1686 eivlen = EVP_CIPHER_CTX_iv_length(s->enc_write_ctx); 1687 if (eivlen <= 1) 1688 eivlen = 0; 1689 } 1690 /* Need explicit part of IV for GCM mode */ 1691 else if (mode == EVP_CIPH_GCM_MODE) 1692 eivlen = EVP_GCM_TLS_EXPLICIT_IV_LEN; 1693 else 1694 eivlen = 0; 1695 } else 1696 eivlen = 0; 1697 1698 /* lets setup the record stuff. */ 1699 wr->data = p + eivlen; /* make room for IV in case of CBC */ 1700 wr->length = (int)len; 1701 wr->input = (unsigned char *)buf; 1702 1703 /* 1704 * we now 'read' from wr->input, wr->length bytes into wr->data 1705 */ 1706 1707 /* first we compress */ 1708 if (s->compress != NULL) { 1709 if (!ssl3_do_compress(s)) { 1710 SSLerr(SSL_F_DO_DTLS1_WRITE, SSL_R_COMPRESSION_FAILURE); 1711 goto err; 1712 } 1713 } else { 1714 memcpy(wr->data, wr->input, wr->length); 1715 wr->input = wr->data; 1716 } 1717 1718 /* 1719 * we should still have the output to wr->data and the input from 1720 * wr->input. Length should be wr->length. wr->data still points in the 1721 * wb->buf 1722 */ 1723 1724 if (mac_size != 0) { 1725 if (s->method->ssl3_enc->mac(s, &(p[wr->length + eivlen]), 1) < 0) 1726 goto err; 1727 wr->length += mac_size; 1728 } 1729 1730 /* this is true regardless of mac size */ 1731 wr->input = p; 1732 wr->data = p; 1733 1734 if (eivlen) 1735 wr->length += eivlen; 1736 1737 if (s->method->ssl3_enc->enc(s, 1) < 1) 1738 goto err; 1739 1740 /* record length after mac and block padding */ 1741 /* 1742 * if (type == SSL3_RT_APPLICATION_DATA || (type == SSL3_RT_ALERT && ! 1743 * SSL_in_init(s))) 1744 */ 1745 1746 /* there's only one epoch between handshake and app data */ 1747 1748 s2n(s->d1->w_epoch, pseq); 1749 1750 /* XDTLS: ?? */ 1751 /* 1752 * else s2n(s->d1->handshake_epoch, pseq); 1753 */ 1754 1755 memcpy(pseq, &(s->s3->write_sequence[2]), 6); 1756 pseq += 6; 1757 s2n(wr->length, pseq); 1758 1759 if (s->msg_callback) 1760 s->msg_callback(1, 0, SSL3_RT_HEADER, pseq - DTLS1_RT_HEADER_LENGTH, 1761 DTLS1_RT_HEADER_LENGTH, s, s->msg_callback_arg); 1762 1763 /* 1764 * we should now have wr->data pointing to the encrypted data, which is 1765 * wr->length long 1766 */ 1767 wr->type = type; /* not needed but helps for debugging */ 1768 wr->length += DTLS1_RT_HEADER_LENGTH; 1769 1770#if 0 /* this is now done at the message layer */ 1771 /* buffer the record, making it easy to handle retransmits */ 1772 if (type == SSL3_RT_HANDSHAKE || type == SSL3_RT_CHANGE_CIPHER_SPEC) 1773 dtls1_buffer_record(s, wr->data, wr->length, 1774 *((PQ_64BIT *) & (s->s3->write_sequence[0]))); 1775#endif 1776 1777 ssl3_record_sequence_update(&(s->s3->write_sequence[0])); 1778 1779 if (create_empty_fragment) { 1780 /* 1781 * we are in a recursive call; just return the length, don't write 1782 * out anything here 1783 */ 1784 return wr->length; 1785 } 1786 1787 /* now let's set up wb */ 1788 wb->left = prefix_len + wr->length; 1789 wb->offset = 0; 1790 1791 /* 1792 * memorize arguments so that ssl3_write_pending can detect bad write 1793 * retries later 1794 */ 1795 s->s3->wpend_tot = len; 1796 s->s3->wpend_buf = buf; 1797 s->s3->wpend_type = type; 1798 s->s3->wpend_ret = len; 1799 1800 /* we now just need to write the buffer */ 1801 return ssl3_write_pending(s, type, buf, len); 1802 err: 1803 return -1; 1804} 1805 1806static int dtls1_record_replay_check(SSL *s, DTLS1_BITMAP *bitmap) 1807{ 1808 int cmp; 1809 unsigned int shift; 1810 const unsigned char *seq = s->s3->read_sequence; 1811 1812 cmp = satsub64be(seq, bitmap->max_seq_num); 1813 if (cmp > 0) { 1814 memcpy(s->s3->rrec.seq_num, seq, 8); 1815 return 1; /* this record in new */ 1816 } 1817 shift = -cmp; 1818 if (shift >= sizeof(bitmap->map) * 8) 1819 return 0; /* stale, outside the window */ 1820 else if (bitmap->map & (1UL << shift)) 1821 return 0; /* record previously received */ 1822 1823 memcpy(s->s3->rrec.seq_num, seq, 8); 1824 return 1; 1825} 1826 1827static void dtls1_record_bitmap_update(SSL *s, DTLS1_BITMAP *bitmap) 1828{ 1829 int cmp; 1830 unsigned int shift; 1831 const unsigned char *seq = s->s3->read_sequence; 1832 1833 cmp = satsub64be(seq, bitmap->max_seq_num); 1834 if (cmp > 0) { 1835 shift = cmp; 1836 if (shift < sizeof(bitmap->map) * 8) 1837 bitmap->map <<= shift, bitmap->map |= 1UL; 1838 else 1839 bitmap->map = 1UL; 1840 memcpy(bitmap->max_seq_num, seq, 8); 1841 } else { 1842 shift = -cmp; 1843 if (shift < sizeof(bitmap->map) * 8) 1844 bitmap->map |= 1UL << shift; 1845 } 1846} 1847 1848int dtls1_dispatch_alert(SSL *s) 1849{ 1850 int i, j; 1851 void (*cb) (const SSL *ssl, int type, int val) = NULL; 1852 unsigned char buf[DTLS1_AL_HEADER_LENGTH]; 1853 unsigned char *ptr = &buf[0]; 1854 1855 s->s3->alert_dispatch = 0; 1856 1857 memset(buf, 0x00, sizeof(buf)); 1858 *ptr++ = s->s3->send_alert[0]; 1859 *ptr++ = s->s3->send_alert[1]; 1860 1861#ifdef DTLS1_AD_MISSING_HANDSHAKE_MESSAGE 1862 if (s->s3->send_alert[1] == DTLS1_AD_MISSING_HANDSHAKE_MESSAGE) { 1863 s2n(s->d1->handshake_read_seq, ptr); 1864# if 0 1865 if (s->d1->r_msg_hdr.frag_off == 0) 1866 /* 1867 * waiting for a new msg 1868 */ 1869 else 1870 s2n(s->d1->r_msg_hdr.seq, ptr); /* partial msg read */ 1871# endif 1872 1873# if 0 1874 fprintf(stderr, 1875 "s->d1->handshake_read_seq = %d, s->d1->r_msg_hdr.seq = %d\n", 1876 s->d1->handshake_read_seq, s->d1->r_msg_hdr.seq); 1877# endif 1878 l2n3(s->d1->r_msg_hdr.frag_off, ptr); 1879 } 1880#endif 1881 1882 i = do_dtls1_write(s, SSL3_RT_ALERT, &buf[0], sizeof(buf), 0); 1883 if (i <= 0) { 1884 s->s3->alert_dispatch = 1; 1885 /* fprintf( stderr, "not done with alert\n" ); */ 1886 } else { 1887 if (s->s3->send_alert[0] == SSL3_AL_FATAL 1888#ifdef DTLS1_AD_MISSING_HANDSHAKE_MESSAGE 1889 || s->s3->send_alert[1] == DTLS1_AD_MISSING_HANDSHAKE_MESSAGE 1890#endif 1891 ) 1892 (void)BIO_flush(s->wbio); 1893 1894 if (s->msg_callback) 1895 s->msg_callback(1, s->version, SSL3_RT_ALERT, s->s3->send_alert, 1896 2, s, s->msg_callback_arg); 1897 1898 if (s->info_callback != NULL) 1899 cb = s->info_callback; 1900 else if (s->ctx->info_callback != NULL) 1901 cb = s->ctx->info_callback; 1902 1903 if (cb != NULL) { 1904 j = (s->s3->send_alert[0] << 8) | s->s3->send_alert[1]; 1905 cb(s, SSL_CB_WRITE_ALERT, j); 1906 } 1907 } 1908 return (i); 1909} 1910 1911static DTLS1_BITMAP *dtls1_get_bitmap(SSL *s, SSL3_RECORD *rr, 1912 unsigned int *is_next_epoch) 1913{ 1914 1915 *is_next_epoch = 0; 1916 1917 /* In current epoch, accept HM, CCS, DATA, & ALERT */ 1918 if (rr->epoch == s->d1->r_epoch) 1919 return &s->d1->bitmap; 1920 1921 /* 1922 * Only HM and ALERT messages can be from the next epoch and only if we 1923 * have already processed all of the unprocessed records from the last 1924 * epoch 1925 */ 1926 else if (rr->epoch == (unsigned long)(s->d1->r_epoch + 1) && 1927 s->d1->unprocessed_rcds.epoch != s->d1->r_epoch && 1928 (rr->type == SSL3_RT_HANDSHAKE || rr->type == SSL3_RT_ALERT)) { 1929 *is_next_epoch = 1; 1930 return &s->d1->next_bitmap; 1931 } 1932 1933 return NULL; 1934} 1935 1936#if 0 1937static int 1938dtls1_record_needs_buffering(SSL *s, SSL3_RECORD *rr, 1939 unsigned short *priority, unsigned long *offset) 1940{ 1941 1942 /* alerts are passed up immediately */ 1943 if (rr->type == SSL3_RT_APPLICATION_DATA || rr->type == SSL3_RT_ALERT) 1944 return 0; 1945 1946 /* 1947 * Only need to buffer if a handshake is underway. (this implies that 1948 * Hello Request and Client Hello are passed up immediately) 1949 */ 1950 if (SSL_in_init(s)) { 1951 unsigned char *data = rr->data; 1952 /* need to extract the HM/CCS sequence number here */ 1953 if (rr->type == SSL3_RT_HANDSHAKE || 1954 rr->type == SSL3_RT_CHANGE_CIPHER_SPEC) { 1955 unsigned short seq_num; 1956 struct hm_header_st msg_hdr; 1957 struct ccs_header_st ccs_hdr; 1958 1959 if (rr->type == SSL3_RT_HANDSHAKE) { 1960 dtls1_get_message_header(data, &msg_hdr); 1961 seq_num = msg_hdr.seq; 1962 *offset = msg_hdr.frag_off; 1963 } else { 1964 dtls1_get_ccs_header(data, &ccs_hdr); 1965 seq_num = ccs_hdr.seq; 1966 *offset = 0; 1967 } 1968 1969 /* 1970 * this is either a record we're waiting for, or a retransmit of 1971 * something we happened to previously receive (higher layers 1972 * will drop the repeat silently 1973 */ 1974 if (seq_num < s->d1->handshake_read_seq) 1975 return 0; 1976 if (rr->type == SSL3_RT_HANDSHAKE && 1977 seq_num == s->d1->handshake_read_seq && 1978 msg_hdr.frag_off < s->d1->r_msg_hdr.frag_off) 1979 return 0; 1980 else if (seq_num == s->d1->handshake_read_seq && 1981 (rr->type == SSL3_RT_CHANGE_CIPHER_SPEC || 1982 msg_hdr.frag_off == s->d1->r_msg_hdr.frag_off)) 1983 return 0; 1984 else { 1985 *priority = seq_num; 1986 return 1; 1987 } 1988 } else /* unknown record type */ 1989 return 0; 1990 } 1991 1992 return 0; 1993} 1994#endif 1995 1996void dtls1_reset_seq_numbers(SSL *s, int rw) 1997{ 1998 unsigned char *seq; 1999 unsigned int seq_bytes = sizeof(s->s3->read_sequence); 2000 2001 if (rw & SSL3_CC_READ) { 2002 seq = s->s3->read_sequence; 2003 s->d1->r_epoch++; 2004 memcpy(&(s->d1->bitmap), &(s->d1->next_bitmap), sizeof(DTLS1_BITMAP)); 2005 memset(&(s->d1->next_bitmap), 0x00, sizeof(DTLS1_BITMAP)); 2006 2007 /* 2008 * We must not use any buffered messages received from the previous 2009 * epoch 2010 */ 2011 dtls1_clear_received_buffer(s); 2012 } else { 2013 seq = s->s3->write_sequence; 2014 memcpy(s->d1->last_write_sequence, seq, 2015 sizeof(s->s3->write_sequence)); 2016 s->d1->w_epoch++; 2017 } 2018 2019 memset(seq, 0x00, seq_bytes); 2020} 2021