d1_pkt.c revision 348343
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) 1998-2019 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 if (pqueue_insert(queue->q, item) == NULL) { 297 /* Must be a duplicate so ignore it */ 298 if (rdata->rbuf.buf != NULL) 299 OPENSSL_free(rdata->rbuf.buf); 300 OPENSSL_free(rdata); 301 pitem_free(item); 302 } 303 304 return (1); 305} 306 307static int dtls1_retrieve_buffered_record(SSL *s, record_pqueue *queue) 308{ 309 pitem *item; 310 311 item = pqueue_pop(queue->q); 312 if (item) { 313 dtls1_copy_record(s, item); 314 315 OPENSSL_free(item->data); 316 pitem_free(item); 317 318 return (1); 319 } 320 321 return (0); 322} 323 324/* 325 * retrieve a buffered record that belongs to the new epoch, i.e., not 326 * processed yet 327 */ 328#define dtls1_get_unprocessed_record(s) \ 329 dtls1_retrieve_buffered_record((s), \ 330 &((s)->d1->unprocessed_rcds)) 331 332/* 333 * retrieve a buffered record that belongs to the current epoch, ie, 334 * processed 335 */ 336#define dtls1_get_processed_record(s) \ 337 dtls1_retrieve_buffered_record((s), \ 338 &((s)->d1->processed_rcds)) 339 340static int dtls1_process_buffered_records(SSL *s) 341{ 342 pitem *item; 343 SSL3_BUFFER *rb; 344 SSL3_RECORD *rr; 345 DTLS1_BITMAP *bitmap; 346 unsigned int is_next_epoch; 347 int replayok = 1; 348 349 item = pqueue_peek(s->d1->unprocessed_rcds.q); 350 if (item) { 351 /* Check if epoch is current. */ 352 if (s->d1->unprocessed_rcds.epoch != s->d1->r_epoch) 353 return 1; /* Nothing to do. */ 354 355 rr = &s->s3->rrec; 356 rb = &s->s3->rbuf; 357 358 if (rb->left > 0) { 359 /* 360 * We've still got data from the current packet to read. There could 361 * be a record from the new epoch in it - so don't overwrite it 362 * with the unprocessed records yet (we'll do it when we've 363 * finished reading the current packet). 364 */ 365 return 1; 366 } 367 368 369 /* Process all the records. */ 370 while (pqueue_peek(s->d1->unprocessed_rcds.q)) { 371 dtls1_get_unprocessed_record(s); 372 bitmap = dtls1_get_bitmap(s, rr, &is_next_epoch); 373 if (bitmap == NULL) { 374 /* 375 * Should not happen. This will only ever be NULL when the 376 * current record is from a different epoch. But that cannot 377 * be the case because we already checked the epoch above 378 */ 379 SSLerr(SSL_F_DTLS1_PROCESS_BUFFERED_RECORDS, 380 ERR_R_INTERNAL_ERROR); 381 return 0; 382 } 383#ifndef OPENSSL_NO_SCTP 384 /* Only do replay check if no SCTP bio */ 385 if (!BIO_dgram_is_sctp(SSL_get_rbio(s))) 386#endif 387 { 388 /* 389 * Check whether this is a repeat, or aged record. We did this 390 * check once already when we first received the record - but 391 * we might have updated the window since then due to 392 * records we subsequently processed. 393 */ 394 replayok = dtls1_record_replay_check(s, bitmap); 395 } 396 397 if (!replayok || !dtls1_process_record(s, bitmap)) { 398 /* dump this record */ 399 rr->length = 0; 400 s->packet_length = 0; 401 continue; 402 } 403 404 if (dtls1_buffer_record(s, &(s->d1->processed_rcds), 405 s->s3->rrec.seq_num) < 0) 406 return 0; 407 } 408 } 409 410 /* 411 * sync epoch numbers once all the unprocessed records have been 412 * processed 413 */ 414 s->d1->processed_rcds.epoch = s->d1->r_epoch; 415 s->d1->unprocessed_rcds.epoch = s->d1->r_epoch + 1; 416 417 return 1; 418} 419 420#if 0 421 422static int dtls1_get_buffered_record(SSL *s) 423{ 424 pitem *item; 425 PQ_64BIT priority = 426 (((PQ_64BIT) s->d1->handshake_read_seq) << 32) | 427 ((PQ_64BIT) s->d1->r_msg_hdr.frag_off); 428 429 /* if we're not (re)negotiating, nothing buffered */ 430 if (!SSL_in_init(s)) 431 return 0; 432 433 item = pqueue_peek(s->d1->rcvd_records); 434 if (item && item->priority == priority) { 435 /* 436 * Check if we've received the record of interest. It must be a 437 * handshake record, since data records as passed up without 438 * buffering 439 */ 440 DTLS1_RECORD_DATA *rdata; 441 item = pqueue_pop(s->d1->rcvd_records); 442 rdata = (DTLS1_RECORD_DATA *)item->data; 443 444 if (s->s3->rbuf.buf != NULL) 445 OPENSSL_free(s->s3->rbuf.buf); 446 447 s->packet = rdata->packet; 448 s->packet_length = rdata->packet_length; 449 memcpy(&(s->s3->rbuf), &(rdata->rbuf), sizeof(SSL3_BUFFER)); 450 memcpy(&(s->s3->rrec), &(rdata->rrec), sizeof(SSL3_RECORD)); 451 452 OPENSSL_free(item->data); 453 pitem_free(item); 454 455 /* s->d1->next_expected_seq_num++; */ 456 return (1); 457 } 458 459 return 0; 460} 461 462#endif 463 464static int dtls1_process_record(SSL *s, DTLS1_BITMAP *bitmap) 465{ 466 int i, al; 467 int enc_err; 468 SSL_SESSION *sess; 469 SSL3_RECORD *rr; 470 unsigned int mac_size, orig_len; 471 unsigned char md[EVP_MAX_MD_SIZE]; 472 473 rr = &(s->s3->rrec); 474 sess = s->session; 475 476 /* 477 * At this point, s->packet_length == SSL3_RT_HEADER_LNGTH + rr->length, 478 * and we have that many bytes in s->packet 479 */ 480 rr->input = &(s->packet[DTLS1_RT_HEADER_LENGTH]); 481 482 /* 483 * ok, we can now read from 's->packet' data into 'rr' rr->input points 484 * at rr->length bytes, which need to be copied into rr->data by either 485 * the decryption or by the decompression When the data is 'copied' into 486 * the rr->data buffer, rr->input will be pointed at the new buffer 487 */ 488 489 /* 490 * We now have - encrypted [ MAC [ compressed [ plain ] ] ] rr->length 491 * bytes of encrypted compressed stuff. 492 */ 493 494 /* check is not needed I believe */ 495 if (rr->length > SSL3_RT_MAX_ENCRYPTED_LENGTH) { 496 al = SSL_AD_RECORD_OVERFLOW; 497 SSLerr(SSL_F_DTLS1_PROCESS_RECORD, SSL_R_ENCRYPTED_LENGTH_TOO_LONG); 498 goto f_err; 499 } 500 501 /* decrypt in place in 'rr->input' */ 502 rr->data = rr->input; 503 504 enc_err = s->method->ssl3_enc->enc(s, 0); 505 /*- 506 * enc_err is: 507 * 0: (in non-constant time) if the record is publically invalid. 508 * 1: if the padding is valid 509 * -1: if the padding is invalid 510 */ 511 if (enc_err == 0) { 512 /* For DTLS we simply ignore bad packets. */ 513 rr->length = 0; 514 s->packet_length = 0; 515 goto err; 516 } 517#ifdef TLS_DEBUG 518 printf("dec %d\n", rr->length); 519 { 520 unsigned int z; 521 for (z = 0; z < rr->length; z++) 522 printf("%02X%c", rr->data[z], ((z + 1) % 16) ? ' ' : '\n'); 523 } 524 printf("\n"); 525#endif 526 527 /* r->length is now the compressed data plus mac */ 528 if ((sess != NULL) && 529 (s->enc_read_ctx != NULL) && (EVP_MD_CTX_md(s->read_hash) != NULL)) { 530 /* s->read_hash != NULL => mac_size != -1 */ 531 unsigned char *mac = NULL; 532 unsigned char mac_tmp[EVP_MAX_MD_SIZE]; 533 mac_size = EVP_MD_CTX_size(s->read_hash); 534 OPENSSL_assert(mac_size <= EVP_MAX_MD_SIZE); 535 536 /* 537 * kludge: *_cbc_remove_padding passes padding length in rr->type 538 */ 539 orig_len = rr->length + ((unsigned int)rr->type >> 8); 540 541 /* 542 * orig_len is the length of the record before any padding was 543 * removed. This is public information, as is the MAC in use, 544 * therefore we can safely process the record in a different amount 545 * of time if it's too short to possibly contain a MAC. 546 */ 547 if (orig_len < mac_size || 548 /* CBC records must have a padding length byte too. */ 549 (EVP_CIPHER_CTX_mode(s->enc_read_ctx) == EVP_CIPH_CBC_MODE && 550 orig_len < mac_size + 1)) { 551 al = SSL_AD_DECODE_ERROR; 552 SSLerr(SSL_F_DTLS1_PROCESS_RECORD, SSL_R_LENGTH_TOO_SHORT); 553 goto f_err; 554 } 555 556 if (EVP_CIPHER_CTX_mode(s->enc_read_ctx) == EVP_CIPH_CBC_MODE) { 557 /* 558 * We update the length so that the TLS header bytes can be 559 * constructed correctly but we need to extract the MAC in 560 * constant time from within the record, without leaking the 561 * contents of the padding bytes. 562 */ 563 mac = mac_tmp; 564 ssl3_cbc_copy_mac(mac_tmp, rr, mac_size, orig_len); 565 rr->length -= mac_size; 566 } else { 567 /* 568 * In this case there's no padding, so |orig_len| equals 569 * |rec->length| and we checked that there's enough bytes for 570 * |mac_size| above. 571 */ 572 rr->length -= mac_size; 573 mac = &rr->data[rr->length]; 574 } 575 576 i = s->method->ssl3_enc->mac(s, md, 0 /* not send */ ); 577 if (i < 0 || mac == NULL 578 || CRYPTO_memcmp(md, mac, (size_t)mac_size) != 0) 579 enc_err = -1; 580 if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH + mac_size) 581 enc_err = -1; 582 } 583 584 if (enc_err < 0) { 585 /* decryption failed, silently discard message */ 586 rr->length = 0; 587 s->packet_length = 0; 588 goto err; 589 } 590 591 /* r->length is now just compressed */ 592 if (s->expand != NULL) { 593 if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH) { 594 al = SSL_AD_RECORD_OVERFLOW; 595 SSLerr(SSL_F_DTLS1_PROCESS_RECORD, 596 SSL_R_COMPRESSED_LENGTH_TOO_LONG); 597 goto f_err; 598 } 599 if (!ssl3_do_uncompress(s)) { 600 al = SSL_AD_DECOMPRESSION_FAILURE; 601 SSLerr(SSL_F_DTLS1_PROCESS_RECORD, SSL_R_BAD_DECOMPRESSION); 602 goto f_err; 603 } 604 } 605 606 if (rr->length > SSL3_RT_MAX_PLAIN_LENGTH) { 607 al = SSL_AD_RECORD_OVERFLOW; 608 SSLerr(SSL_F_DTLS1_PROCESS_RECORD, SSL_R_DATA_LENGTH_TOO_LONG); 609 goto f_err; 610 } 611 612 rr->off = 0; 613 /*- 614 * So at this point the following is true 615 * ssl->s3->rrec.type is the type of record 616 * ssl->s3->rrec.length == number of bytes in record 617 * ssl->s3->rrec.off == offset to first valid byte 618 * ssl->s3->rrec.data == where to take bytes from, increment 619 * after use :-). 620 */ 621 622 /* we have pulled in a full packet so zero things */ 623 s->packet_length = 0; 624 625 /* Mark receipt of record. */ 626 dtls1_record_bitmap_update(s, bitmap); 627 628 return (1); 629 630 f_err: 631 ssl3_send_alert(s, SSL3_AL_FATAL, al); 632 err: 633 return (0); 634} 635 636/*- 637 * Call this to get a new input record. 638 * It will return <= 0 if more data is needed, normally due to an error 639 * or non-blocking IO. 640 * When it finishes, one packet has been decoded and can be found in 641 * ssl->s3->rrec.type - is the type of record 642 * ssl->s3->rrec.data, - data 643 * ssl->s3->rrec.length, - number of bytes 644 */ 645/* used only by dtls1_read_bytes */ 646int dtls1_get_record(SSL *s) 647{ 648 int ssl_major, ssl_minor; 649 int i, n; 650 SSL3_RECORD *rr; 651 unsigned char *p = NULL; 652 unsigned short version; 653 DTLS1_BITMAP *bitmap; 654 unsigned int is_next_epoch; 655 656 rr = &(s->s3->rrec); 657 658 again: 659 /* 660 * The epoch may have changed. If so, process all the pending records. 661 * This is a non-blocking operation. 662 */ 663 if (!dtls1_process_buffered_records(s)) 664 return -1; 665 666 /* if we're renegotiating, then there may be buffered records */ 667 if (dtls1_get_processed_record(s)) 668 return 1; 669 670 /* get something from the wire */ 671 /* check if we have the header */ 672 if ((s->rstate != SSL_ST_READ_BODY) || 673 (s->packet_length < DTLS1_RT_HEADER_LENGTH)) { 674 n = ssl3_read_n(s, DTLS1_RT_HEADER_LENGTH, s->s3->rbuf.len, 0); 675 /* read timeout is handled by dtls1_read_bytes */ 676 if (n <= 0) 677 return (n); /* error or non-blocking */ 678 679 /* this packet contained a partial record, dump it */ 680 if (s->packet_length != DTLS1_RT_HEADER_LENGTH) { 681 s->packet_length = 0; 682 goto again; 683 } 684 685 s->rstate = SSL_ST_READ_BODY; 686 687 p = s->packet; 688 689 if (s->msg_callback) 690 s->msg_callback(0, 0, SSL3_RT_HEADER, p, DTLS1_RT_HEADER_LENGTH, 691 s, s->msg_callback_arg); 692 693 /* Pull apart the header into the DTLS1_RECORD */ 694 rr->type = *(p++); 695 ssl_major = *(p++); 696 ssl_minor = *(p++); 697 version = (ssl_major << 8) | ssl_minor; 698 699 /* sequence number is 64 bits, with top 2 bytes = epoch */ 700 n2s(p, rr->epoch); 701 702 memcpy(&(s->s3->read_sequence[2]), p, 6); 703 p += 6; 704 705 n2s(p, rr->length); 706 707 /* 708 * Lets check the version. We tolerate alerts that don't have the exact 709 * version number (e.g. because of protocol version errors) 710 */ 711 if (!s->first_packet && rr->type != SSL3_RT_ALERT) { 712 if (version != s->version) { 713 /* unexpected version, silently discard */ 714 rr->length = 0; 715 s->packet_length = 0; 716 goto again; 717 } 718 } 719 720 if ((version & 0xff00) != (s->version & 0xff00)) { 721 /* wrong version, silently discard record */ 722 rr->length = 0; 723 s->packet_length = 0; 724 goto again; 725 } 726 727 if (rr->length > SSL3_RT_MAX_ENCRYPTED_LENGTH) { 728 /* record too long, silently discard it */ 729 rr->length = 0; 730 s->packet_length = 0; 731 goto again; 732 } 733 734 /* now s->rstate == SSL_ST_READ_BODY */ 735 } 736 737 /* s->rstate == SSL_ST_READ_BODY, get and decode the data */ 738 739 if (rr->length > s->packet_length - DTLS1_RT_HEADER_LENGTH) { 740 /* now s->packet_length == DTLS1_RT_HEADER_LENGTH */ 741 i = rr->length; 742 n = ssl3_read_n(s, i, i, 1); 743 /* this packet contained a partial record, dump it */ 744 if (n != i) { 745 rr->length = 0; 746 s->packet_length = 0; 747 goto again; 748 } 749 750 /* 751 * now n == rr->length, and s->packet_length == 752 * DTLS1_RT_HEADER_LENGTH + rr->length 753 */ 754 } 755 s->rstate = SSL_ST_READ_HEADER; /* set state for later operations */ 756 757 /* match epochs. NULL means the packet is dropped on the floor */ 758 bitmap = dtls1_get_bitmap(s, rr, &is_next_epoch); 759 if (bitmap == NULL) { 760 rr->length = 0; 761 s->packet_length = 0; /* dump this record */ 762 goto again; /* get another record */ 763 } 764#ifndef OPENSSL_NO_SCTP 765 /* Only do replay check if no SCTP bio */ 766 if (!BIO_dgram_is_sctp(SSL_get_rbio(s))) { 767#endif 768 /* 769 * Check whether this is a repeat, or aged record. Don't check if 770 * we're listening and this message is a ClientHello. They can look 771 * as if they're replayed, since they arrive from different 772 * connections and would be dropped unnecessarily. 773 */ 774 if (!(s->d1->listen && rr->type == SSL3_RT_HANDSHAKE && 775 s->packet_length > DTLS1_RT_HEADER_LENGTH && 776 s->packet[DTLS1_RT_HEADER_LENGTH] == SSL3_MT_CLIENT_HELLO) && 777 !dtls1_record_replay_check(s, bitmap)) { 778 rr->length = 0; 779 s->packet_length = 0; /* dump this record */ 780 goto again; /* get another record */ 781 } 782#ifndef OPENSSL_NO_SCTP 783 } 784#endif 785 786 /* just read a 0 length packet */ 787 if (rr->length == 0) 788 goto again; 789 790 /* 791 * If this record is from the next epoch (either HM or ALERT), and a 792 * handshake is currently in progress, buffer it since it cannot be 793 * processed at this time. However, do not buffer anything while 794 * listening. 795 */ 796 if (is_next_epoch) { 797 if ((SSL_in_init(s) || s->in_handshake) && !s->d1->listen) { 798 if (dtls1_buffer_record 799 (s, &(s->d1->unprocessed_rcds), rr->seq_num) < 0) 800 return -1; 801 } 802 rr->length = 0; 803 s->packet_length = 0; 804 goto again; 805 } 806 807 if (!dtls1_process_record(s, bitmap)) { 808 rr->length = 0; 809 s->packet_length = 0; /* dump this record */ 810 goto again; /* get another record */ 811 } 812 813 return (1); 814 815} 816 817/*- 818 * Return up to 'len' payload bytes received in 'type' records. 819 * 'type' is one of the following: 820 * 821 * - SSL3_RT_HANDSHAKE (when ssl3_get_message calls us) 822 * - SSL3_RT_APPLICATION_DATA (when ssl3_read calls us) 823 * - 0 (during a shutdown, no data has to be returned) 824 * 825 * If we don't have stored data to work from, read a SSL/TLS record first 826 * (possibly multiple records if we still don't have anything to return). 827 * 828 * This function must handle any surprises the peer may have for us, such as 829 * Alert records (e.g. close_notify), ChangeCipherSpec records (not really 830 * a surprise, but handled as if it were), or renegotiation requests. 831 * Also if record payloads contain fragments too small to process, we store 832 * them until there is enough for the respective protocol (the record protocol 833 * may use arbitrary fragmentation and even interleaving): 834 * Change cipher spec protocol 835 * just 1 byte needed, no need for keeping anything stored 836 * Alert protocol 837 * 2 bytes needed (AlertLevel, AlertDescription) 838 * Handshake protocol 839 * 4 bytes needed (HandshakeType, uint24 length) -- we just have 840 * to detect unexpected Client Hello and Hello Request messages 841 * here, anything else is handled by higher layers 842 * Application data protocol 843 * none of our business 844 */ 845int dtls1_read_bytes(SSL *s, int type, unsigned char *buf, int len, int peek) 846{ 847 int al, i, j, ret; 848 unsigned int n; 849 SSL3_RECORD *rr; 850 void (*cb) (const SSL *ssl, int type2, int val) = NULL; 851 852 if (s->s3->rbuf.buf == NULL) /* Not initialized yet */ 853 if (!ssl3_setup_buffers(s)) 854 return (-1); 855 856 /* XXX: check what the second '&& type' is about */ 857 if ((type && (type != SSL3_RT_APPLICATION_DATA) && 858 (type != SSL3_RT_HANDSHAKE) && type) || 859 (peek && (type != SSL3_RT_APPLICATION_DATA))) { 860 SSLerr(SSL_F_DTLS1_READ_BYTES, ERR_R_INTERNAL_ERROR); 861 return -1; 862 } 863 864 /* 865 * check whether there's a handshake message (client hello?) waiting 866 */ 867 if ((ret = have_handshake_fragment(s, type, buf, len, peek))) 868 return ret; 869 870 /* 871 * Now s->d1->handshake_fragment_len == 0 if type == SSL3_RT_HANDSHAKE. 872 */ 873 874#ifndef OPENSSL_NO_SCTP 875 /* 876 * Continue handshake if it had to be interrupted to read app data with 877 * SCTP. 878 */ 879 if ((!s->in_handshake && SSL_in_init(s)) || 880 (BIO_dgram_is_sctp(SSL_get_rbio(s)) && 881 (s->state == DTLS1_SCTP_ST_SR_READ_SOCK 882 || s->state == DTLS1_SCTP_ST_CR_READ_SOCK) 883 && s->s3->in_read_app_data != 2)) 884#else 885 if (!s->in_handshake && SSL_in_init(s)) 886#endif 887 { 888 /* type == SSL3_RT_APPLICATION_DATA */ 889 i = s->handshake_func(s); 890 if (i < 0) 891 return (i); 892 if (i == 0) { 893 SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_R_SSL_HANDSHAKE_FAILURE); 894 return (-1); 895 } 896 } 897 898 start: 899 s->rwstate = SSL_NOTHING; 900 901 /*- 902 * s->s3->rrec.type - is the type of record 903 * s->s3->rrec.data, - data 904 * s->s3->rrec.off, - offset into 'data' for next read 905 * s->s3->rrec.length, - number of bytes. 906 */ 907 rr = &(s->s3->rrec); 908 909 /* 910 * We are not handshaking and have no data yet, so process data buffered 911 * during the last handshake in advance, if any. 912 */ 913 if (s->state == SSL_ST_OK && rr->length == 0) { 914 pitem *item; 915 item = pqueue_pop(s->d1->buffered_app_data.q); 916 if (item) { 917#ifndef OPENSSL_NO_SCTP 918 /* Restore bio_dgram_sctp_rcvinfo struct */ 919 if (BIO_dgram_is_sctp(SSL_get_rbio(s))) { 920 DTLS1_RECORD_DATA *rdata = (DTLS1_RECORD_DATA *)item->data; 921 BIO_ctrl(SSL_get_rbio(s), BIO_CTRL_DGRAM_SCTP_SET_RCVINFO, 922 sizeof(rdata->recordinfo), &rdata->recordinfo); 923 } 924#endif 925 926 dtls1_copy_record(s, item); 927 928 OPENSSL_free(item->data); 929 pitem_free(item); 930 } 931 } 932 933 /* Check for timeout */ 934 if (dtls1_handle_timeout(s) > 0) 935 goto start; 936 937 /* get new packet if necessary */ 938 if ((rr->length == 0) || (s->rstate == SSL_ST_READ_BODY)) { 939 ret = dtls1_get_record(s); 940 if (ret <= 0) { 941 ret = dtls1_read_failed(s, ret); 942 /* anything other than a timeout is an error */ 943 if (ret <= 0) 944 return (ret); 945 else 946 goto start; 947 } 948 } 949 950 if (s->d1->listen && rr->type != SSL3_RT_HANDSHAKE) { 951 rr->length = 0; 952 goto start; 953 } 954 955 /* 956 * Reset the count of consecutive warning alerts if we've got a non-empty 957 * record that isn't an alert. 958 */ 959 if (rr->type != SSL3_RT_ALERT && rr->length != 0) 960 s->cert->alert_count = 0; 961 962 /* we now have a packet which can be read and processed */ 963 964 if (s->s3->change_cipher_spec /* set when we receive ChangeCipherSpec, 965 * reset by ssl3_get_finished */ 966 && (rr->type != SSL3_RT_HANDSHAKE)) { 967 /* 968 * We now have application data between CCS and Finished. Most likely 969 * the packets were reordered on their way, so buffer the application 970 * data for later processing rather than dropping the connection. 971 */ 972 if (dtls1_buffer_record(s, &(s->d1->buffered_app_data), rr->seq_num) < 973 0) { 974 SSLerr(SSL_F_DTLS1_READ_BYTES, ERR_R_INTERNAL_ERROR); 975 return -1; 976 } 977 rr->length = 0; 978 goto start; 979 } 980 981 /* 982 * If the other end has shut down, throw anything we read away (even in 983 * 'peek' mode) 984 */ 985 if (s->shutdown & SSL_RECEIVED_SHUTDOWN) { 986 rr->length = 0; 987 s->rwstate = SSL_NOTHING; 988 return (0); 989 } 990 991 if (type == rr->type) { /* SSL3_RT_APPLICATION_DATA or 992 * SSL3_RT_HANDSHAKE */ 993 /* 994 * make sure that we are not getting application data when we are 995 * doing a handshake for the first time 996 */ 997 if (SSL_in_init(s) && (type == SSL3_RT_APPLICATION_DATA) && 998 (s->enc_read_ctx == NULL)) { 999 al = SSL_AD_UNEXPECTED_MESSAGE; 1000 SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_R_APP_DATA_IN_HANDSHAKE); 1001 goto f_err; 1002 } 1003 1004 if (len <= 0) 1005 return (len); 1006 1007 if ((unsigned int)len > rr->length) 1008 n = rr->length; 1009 else 1010 n = (unsigned int)len; 1011 1012 memcpy(buf, &(rr->data[rr->off]), n); 1013 if (!peek) { 1014 rr->length -= n; 1015 rr->off += n; 1016 if (rr->length == 0) { 1017 s->rstate = SSL_ST_READ_HEADER; 1018 rr->off = 0; 1019 } 1020 } 1021#ifndef OPENSSL_NO_SCTP 1022 /* 1023 * We were about to renegotiate but had to read belated application 1024 * data first, so retry. 1025 */ 1026 if (BIO_dgram_is_sctp(SSL_get_rbio(s)) && 1027 rr->type == SSL3_RT_APPLICATION_DATA && 1028 (s->state == DTLS1_SCTP_ST_SR_READ_SOCK 1029 || s->state == DTLS1_SCTP_ST_CR_READ_SOCK)) { 1030 s->rwstate = SSL_READING; 1031 BIO_clear_retry_flags(SSL_get_rbio(s)); 1032 BIO_set_retry_read(SSL_get_rbio(s)); 1033 } 1034 1035 /* 1036 * We might had to delay a close_notify alert because of reordered 1037 * app data. If there was an alert and there is no message to read 1038 * anymore, finally set shutdown. 1039 */ 1040 if (BIO_dgram_is_sctp(SSL_get_rbio(s)) && 1041 s->d1->shutdown_received 1042 && !BIO_dgram_sctp_msg_waiting(SSL_get_rbio(s))) { 1043 s->shutdown |= SSL_RECEIVED_SHUTDOWN; 1044 return (0); 1045 } 1046#endif 1047 return (n); 1048 } 1049 1050 /* 1051 * If we get here, then type != rr->type; if we have a handshake message, 1052 * then it was unexpected (Hello Request or Client Hello). 1053 */ 1054 1055 /* 1056 * In case of record types for which we have 'fragment' storage, fill 1057 * that so that we can process the data at a fixed place. 1058 */ 1059 { 1060 unsigned int k, dest_maxlen = 0; 1061 unsigned char *dest = NULL; 1062 unsigned int *dest_len = NULL; 1063 1064 if (rr->type == SSL3_RT_HANDSHAKE) { 1065 dest_maxlen = sizeof(s->d1->handshake_fragment); 1066 dest = s->d1->handshake_fragment; 1067 dest_len = &s->d1->handshake_fragment_len; 1068 } else if (rr->type == SSL3_RT_ALERT) { 1069 dest_maxlen = sizeof(s->d1->alert_fragment); 1070 dest = s->d1->alert_fragment; 1071 dest_len = &s->d1->alert_fragment_len; 1072 } 1073#ifndef OPENSSL_NO_HEARTBEATS 1074 else if (rr->type == TLS1_RT_HEARTBEAT) { 1075 dtls1_process_heartbeat(s); 1076 1077 /* Exit and notify application to read again */ 1078 rr->length = 0; 1079 s->rwstate = SSL_READING; 1080 BIO_clear_retry_flags(SSL_get_rbio(s)); 1081 BIO_set_retry_read(SSL_get_rbio(s)); 1082 return (-1); 1083 } 1084#endif 1085 /* else it's a CCS message, or application data or wrong */ 1086 else if (rr->type != SSL3_RT_CHANGE_CIPHER_SPEC) { 1087 /* 1088 * Application data while renegotiating is allowed. Try again 1089 * reading. 1090 */ 1091 if (rr->type == SSL3_RT_APPLICATION_DATA) { 1092 BIO *bio; 1093 s->s3->in_read_app_data = 2; 1094 bio = SSL_get_rbio(s); 1095 s->rwstate = SSL_READING; 1096 BIO_clear_retry_flags(bio); 1097 BIO_set_retry_read(bio); 1098 return (-1); 1099 } 1100 1101 /* Not certain if this is the right error handling */ 1102 al = SSL_AD_UNEXPECTED_MESSAGE; 1103 SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_R_UNEXPECTED_RECORD); 1104 goto f_err; 1105 } 1106 1107 if (dest_maxlen > 0) { 1108 /* 1109 * XDTLS: In a pathalogical case, the Client Hello may be 1110 * fragmented--don't always expect dest_maxlen bytes 1111 */ 1112 if (rr->length < dest_maxlen) { 1113#ifdef DTLS1_AD_MISSING_HANDSHAKE_MESSAGE 1114 /* 1115 * for normal alerts rr->length is 2, while 1116 * dest_maxlen is 7 if we were to handle this 1117 * non-existing alert... 1118 */ 1119 FIX ME 1120#endif 1121 s->rstate = SSL_ST_READ_HEADER; 1122 rr->length = 0; 1123 goto start; 1124 } 1125 1126 /* now move 'n' bytes: */ 1127 for (k = 0; k < dest_maxlen; k++) { 1128 dest[k] = rr->data[rr->off++]; 1129 rr->length--; 1130 } 1131 *dest_len = dest_maxlen; 1132 } 1133 } 1134 1135 /*- 1136 * s->d1->handshake_fragment_len == 12 iff rr->type == SSL3_RT_HANDSHAKE; 1137 * s->d1->alert_fragment_len == 7 iff rr->type == SSL3_RT_ALERT. 1138 * (Possibly rr is 'empty' now, i.e. rr->length may be 0.) 1139 */ 1140 1141 /* If we are a client, check for an incoming 'Hello Request': */ 1142 if ((!s->server) && 1143 (s->d1->handshake_fragment_len >= DTLS1_HM_HEADER_LENGTH) && 1144 (s->d1->handshake_fragment[0] == SSL3_MT_HELLO_REQUEST) && 1145 (s->session != NULL) && (s->session->cipher != NULL)) { 1146 s->d1->handshake_fragment_len = 0; 1147 1148 if ((s->d1->handshake_fragment[1] != 0) || 1149 (s->d1->handshake_fragment[2] != 0) || 1150 (s->d1->handshake_fragment[3] != 0)) { 1151 al = SSL_AD_DECODE_ERROR; 1152 SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_R_BAD_HELLO_REQUEST); 1153 goto f_err; 1154 } 1155 1156 /* 1157 * no need to check sequence number on HELLO REQUEST messages 1158 */ 1159 1160 if (s->msg_callback) 1161 s->msg_callback(0, s->version, SSL3_RT_HANDSHAKE, 1162 s->d1->handshake_fragment, 4, s, 1163 s->msg_callback_arg); 1164 1165 if (SSL_is_init_finished(s) && 1166 !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS) && 1167 !s->s3->renegotiate) { 1168 s->d1->handshake_read_seq++; 1169 s->new_session = 1; 1170 ssl3_renegotiate(s); 1171 if (ssl3_renegotiate_check(s)) { 1172 i = s->handshake_func(s); 1173 if (i < 0) 1174 return (i); 1175 if (i == 0) { 1176 SSLerr(SSL_F_DTLS1_READ_BYTES, 1177 SSL_R_SSL_HANDSHAKE_FAILURE); 1178 return (-1); 1179 } 1180 1181 if (!(s->mode & SSL_MODE_AUTO_RETRY)) { 1182 if (s->s3->rbuf.left == 0) { /* no read-ahead left? */ 1183 BIO *bio; 1184 /* 1185 * In the case where we try to read application data, 1186 * but we trigger an SSL handshake, we return -1 with 1187 * the retry option set. Otherwise renegotiation may 1188 * cause nasty problems in the blocking world 1189 */ 1190 s->rwstate = SSL_READING; 1191 bio = SSL_get_rbio(s); 1192 BIO_clear_retry_flags(bio); 1193 BIO_set_retry_read(bio); 1194 return (-1); 1195 } 1196 } 1197 } 1198 } 1199 /* 1200 * we either finished a handshake or ignored the request, now try 1201 * again to obtain the (application) data we were asked for 1202 */ 1203 goto start; 1204 } 1205 1206 /* 1207 * If we are a server and get a client hello when renegotiation isn't 1208 * allowed send back a no renegotiation alert and carry on. 1209 */ 1210 if (s->server 1211 && SSL_is_init_finished(s) 1212 && !s->s3->send_connection_binding 1213 && s->d1->handshake_fragment_len >= DTLS1_HM_HEADER_LENGTH 1214 && s->d1->handshake_fragment[0] == SSL3_MT_CLIENT_HELLO 1215 && s->s3->previous_client_finished_len != 0 1216 && (s->options & SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION) == 0) { 1217 s->d1->handshake_fragment_len = 0; 1218 rr->length = 0; 1219 ssl3_send_alert(s, SSL3_AL_WARNING, SSL_AD_NO_RENEGOTIATION); 1220 goto start; 1221 } 1222 1223 1224 if (s->d1->alert_fragment_len >= DTLS1_AL_HEADER_LENGTH) { 1225 int alert_level = s->d1->alert_fragment[0]; 1226 int alert_descr = s->d1->alert_fragment[1]; 1227 1228 s->d1->alert_fragment_len = 0; 1229 1230 if (s->msg_callback) 1231 s->msg_callback(0, s->version, SSL3_RT_ALERT, 1232 s->d1->alert_fragment, 2, s, s->msg_callback_arg); 1233 1234 if (s->info_callback != NULL) 1235 cb = s->info_callback; 1236 else if (s->ctx->info_callback != NULL) 1237 cb = s->ctx->info_callback; 1238 1239 if (cb != NULL) { 1240 j = (alert_level << 8) | alert_descr; 1241 cb(s, SSL_CB_READ_ALERT, j); 1242 } 1243 1244 if (alert_level == SSL3_AL_WARNING) { 1245 s->s3->warn_alert = alert_descr; 1246 1247 s->cert->alert_count++; 1248 if (s->cert->alert_count == MAX_WARN_ALERT_COUNT) { 1249 al = SSL_AD_UNEXPECTED_MESSAGE; 1250 SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_R_TOO_MANY_WARN_ALERTS); 1251 goto f_err; 1252 } 1253 1254 if (alert_descr == SSL_AD_CLOSE_NOTIFY) { 1255#ifndef OPENSSL_NO_SCTP 1256 /* 1257 * With SCTP and streams the socket may deliver app data 1258 * after a close_notify alert. We have to check this first so 1259 * that nothing gets discarded. 1260 */ 1261 if (BIO_dgram_is_sctp(SSL_get_rbio(s)) && 1262 BIO_dgram_sctp_msg_waiting(SSL_get_rbio(s))) { 1263 s->d1->shutdown_received = 1; 1264 s->rwstate = SSL_READING; 1265 BIO_clear_retry_flags(SSL_get_rbio(s)); 1266 BIO_set_retry_read(SSL_get_rbio(s)); 1267 return -1; 1268 } 1269#endif 1270 s->shutdown |= SSL_RECEIVED_SHUTDOWN; 1271 return (0); 1272 } 1273#if 0 1274 /* XXX: this is a possible improvement in the future */ 1275 /* now check if it's a missing record */ 1276 if (alert_descr == DTLS1_AD_MISSING_HANDSHAKE_MESSAGE) { 1277 unsigned short seq; 1278 unsigned int frag_off; 1279 unsigned char *p = &(s->d1->alert_fragment[2]); 1280 1281 n2s(p, seq); 1282 n2l3(p, frag_off); 1283 1284 dtls1_retransmit_message(s, 1285 dtls1_get_queue_priority 1286 (frag->msg_header.seq, 0), frag_off, 1287 &found); 1288 if (!found && SSL_in_init(s)) { 1289 /* 1290 * fprintf( stderr,"in init = %d\n", SSL_in_init(s)); 1291 */ 1292 /* 1293 * requested a message not yet sent, send an alert 1294 * ourselves 1295 */ 1296 ssl3_send_alert(s, SSL3_AL_WARNING, 1297 DTLS1_AD_MISSING_HANDSHAKE_MESSAGE); 1298 } 1299 } 1300#endif 1301 } else if (alert_level == SSL3_AL_FATAL) { 1302 char tmp[16]; 1303 1304 s->rwstate = SSL_NOTHING; 1305 s->s3->fatal_alert = alert_descr; 1306 SSLerr(SSL_F_DTLS1_READ_BYTES, 1307 SSL_AD_REASON_OFFSET + alert_descr); 1308 BIO_snprintf(tmp, sizeof(tmp), "%d", alert_descr); 1309 ERR_add_error_data(2, "SSL alert number ", tmp); 1310 s->shutdown |= SSL_RECEIVED_SHUTDOWN; 1311 SSL_CTX_remove_session(s->session_ctx, s->session); 1312 s->state = SSL_ST_ERR; 1313 return (0); 1314 } else { 1315 al = SSL_AD_ILLEGAL_PARAMETER; 1316 SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_R_UNKNOWN_ALERT_TYPE); 1317 goto f_err; 1318 } 1319 1320 goto start; 1321 } 1322 1323 if (s->shutdown & SSL_SENT_SHUTDOWN) { /* but we have not received a 1324 * shutdown */ 1325 s->rwstate = SSL_NOTHING; 1326 rr->length = 0; 1327 return (0); 1328 } 1329 1330 if (rr->type == SSL3_RT_CHANGE_CIPHER_SPEC) { 1331 struct ccs_header_st ccs_hdr; 1332 unsigned int ccs_hdr_len = DTLS1_CCS_HEADER_LENGTH; 1333 1334 dtls1_get_ccs_header(rr->data, &ccs_hdr); 1335 1336 if (s->version == DTLS1_BAD_VER) 1337 ccs_hdr_len = 3; 1338 1339 /* 1340 * 'Change Cipher Spec' is just a single byte, so we know exactly 1341 * what the record payload has to look like 1342 */ 1343 /* XDTLS: check that epoch is consistent */ 1344 if ((rr->length != ccs_hdr_len) || 1345 (rr->off != 0) || (rr->data[0] != SSL3_MT_CCS)) { 1346 al = SSL_AD_ILLEGAL_PARAMETER; 1347 SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_R_BAD_CHANGE_CIPHER_SPEC); 1348 goto f_err; 1349 } 1350 1351 rr->length = 0; 1352 1353 if (s->msg_callback) 1354 s->msg_callback(0, s->version, SSL3_RT_CHANGE_CIPHER_SPEC, 1355 rr->data, 1, s, s->msg_callback_arg); 1356 1357 /* 1358 * We can't process a CCS now, because previous handshake messages 1359 * are still missing, so just drop it. 1360 */ 1361 if (!s->d1->change_cipher_spec_ok) { 1362 goto start; 1363 } 1364 1365 s->d1->change_cipher_spec_ok = 0; 1366 1367 s->s3->change_cipher_spec = 1; 1368 if (!ssl3_do_change_cipher_spec(s)) 1369 goto err; 1370 1371 /* do this whenever CCS is processed */ 1372 dtls1_reset_seq_numbers(s, SSL3_CC_READ); 1373 1374 if (s->version == DTLS1_BAD_VER) 1375 s->d1->handshake_read_seq++; 1376 1377#ifndef OPENSSL_NO_SCTP 1378 /* 1379 * Remember that a CCS has been received, so that an old key of 1380 * SCTP-Auth can be deleted when a CCS is sent. Will be ignored if no 1381 * SCTP is used 1382 */ 1383 BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_AUTH_CCS_RCVD, 1, NULL); 1384#endif 1385 1386 goto start; 1387 } 1388 1389 /* 1390 * Unexpected handshake message (Client Hello, or protocol violation) 1391 */ 1392 if ((s->d1->handshake_fragment_len >= DTLS1_HM_HEADER_LENGTH) && 1393 !s->in_handshake) { 1394 struct hm_header_st msg_hdr; 1395 1396 /* this may just be a stale retransmit */ 1397 dtls1_get_message_header(rr->data, &msg_hdr); 1398 if (rr->epoch != s->d1->r_epoch) { 1399 rr->length = 0; 1400 goto start; 1401 } 1402 1403 /* 1404 * If we are server, we may have a repeated FINISHED of the client 1405 * here, then retransmit our CCS and FINISHED. 1406 */ 1407 if (msg_hdr.type == SSL3_MT_FINISHED) { 1408 if (dtls1_check_timeout_num(s) < 0) 1409 return -1; 1410 1411 dtls1_retransmit_buffered_messages(s); 1412 rr->length = 0; 1413 goto start; 1414 } 1415 1416 if (((s->state & SSL_ST_MASK) == SSL_ST_OK) && 1417 !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS)) { 1418#if 0 /* worked only because C operator preferences 1419 * are not as expected (and because this is 1420 * not really needed for clients except for 1421 * detecting protocol violations): */ 1422 s->state = SSL_ST_BEFORE | (s->server) 1423 ? SSL_ST_ACCEPT : SSL_ST_CONNECT; 1424#else 1425 s->state = s->server ? SSL_ST_ACCEPT : SSL_ST_CONNECT; 1426#endif 1427 s->renegotiate = 1; 1428 s->new_session = 1; 1429 } 1430 i = s->handshake_func(s); 1431 if (i < 0) 1432 return (i); 1433 if (i == 0) { 1434 SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_R_SSL_HANDSHAKE_FAILURE); 1435 return (-1); 1436 } 1437 1438 if (!(s->mode & SSL_MODE_AUTO_RETRY)) { 1439 if (s->s3->rbuf.left == 0) { /* no read-ahead left? */ 1440 BIO *bio; 1441 /* 1442 * In the case where we try to read application data, but we 1443 * trigger an SSL handshake, we return -1 with the retry 1444 * option set. Otherwise renegotiation may cause nasty 1445 * problems in the blocking world 1446 */ 1447 s->rwstate = SSL_READING; 1448 bio = SSL_get_rbio(s); 1449 BIO_clear_retry_flags(bio); 1450 BIO_set_retry_read(bio); 1451 return (-1); 1452 } 1453 } 1454 goto start; 1455 } 1456 1457 switch (rr->type) { 1458 default: 1459#ifndef OPENSSL_NO_TLS 1460 /* TLS just ignores unknown message types */ 1461 if (s->version == TLS1_VERSION) { 1462 rr->length = 0; 1463 goto start; 1464 } 1465#endif 1466 al = SSL_AD_UNEXPECTED_MESSAGE; 1467 SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_R_UNEXPECTED_RECORD); 1468 goto f_err; 1469 case SSL3_RT_CHANGE_CIPHER_SPEC: 1470 case SSL3_RT_ALERT: 1471 case SSL3_RT_HANDSHAKE: 1472 /* 1473 * we already handled all of these, with the possible exception of 1474 * SSL3_RT_HANDSHAKE when s->in_handshake is set, but that should not 1475 * happen when type != rr->type 1476 */ 1477 al = SSL_AD_UNEXPECTED_MESSAGE; 1478 SSLerr(SSL_F_DTLS1_READ_BYTES, ERR_R_INTERNAL_ERROR); 1479 goto f_err; 1480 case SSL3_RT_APPLICATION_DATA: 1481 /* 1482 * At this point, we were expecting handshake data, but have 1483 * application data. If the library was running inside ssl3_read() 1484 * (i.e. in_read_app_data is set) and it makes sense to read 1485 * application data at this point (session renegotiation not yet 1486 * started), we will indulge it. 1487 */ 1488 if (s->s3->in_read_app_data && 1489 (s->s3->total_renegotiations != 0) && 1490 (((s->state & SSL_ST_CONNECT) && 1491 (s->state >= SSL3_ST_CW_CLNT_HELLO_A) && 1492 (s->state <= SSL3_ST_CR_SRVR_HELLO_A) 1493 ) || ((s->state & SSL_ST_ACCEPT) && 1494 (s->state <= SSL3_ST_SW_HELLO_REQ_A) && 1495 (s->state >= SSL3_ST_SR_CLNT_HELLO_A) 1496 ) 1497 )) { 1498 s->s3->in_read_app_data = 2; 1499 return (-1); 1500 } else { 1501 al = SSL_AD_UNEXPECTED_MESSAGE; 1502 SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_R_UNEXPECTED_RECORD); 1503 goto f_err; 1504 } 1505 } 1506 /* not reached */ 1507 1508 f_err: 1509 ssl3_send_alert(s, SSL3_AL_FATAL, al); 1510 err: 1511 return (-1); 1512} 1513 1514int dtls1_write_app_data_bytes(SSL *s, int type, const void *buf_, int len) 1515{ 1516 int i; 1517 1518#ifndef OPENSSL_NO_SCTP 1519 /* 1520 * Check if we have to continue an interrupted handshake for reading 1521 * belated app data with SCTP. 1522 */ 1523 if ((SSL_in_init(s) && !s->in_handshake) || 1524 (BIO_dgram_is_sctp(SSL_get_wbio(s)) && 1525 (s->state == DTLS1_SCTP_ST_SR_READ_SOCK 1526 || s->state == DTLS1_SCTP_ST_CR_READ_SOCK))) 1527#else 1528 if (SSL_in_init(s) && !s->in_handshake) 1529#endif 1530 { 1531 i = s->handshake_func(s); 1532 if (i < 0) 1533 return (i); 1534 if (i == 0) { 1535 SSLerr(SSL_F_DTLS1_WRITE_APP_DATA_BYTES, 1536 SSL_R_SSL_HANDSHAKE_FAILURE); 1537 return -1; 1538 } 1539 } 1540 1541 if (len > SSL3_RT_MAX_PLAIN_LENGTH) { 1542 SSLerr(SSL_F_DTLS1_WRITE_APP_DATA_BYTES, SSL_R_DTLS_MESSAGE_TOO_BIG); 1543 return -1; 1544 } 1545 1546 i = dtls1_write_bytes(s, type, buf_, len); 1547 return i; 1548} 1549 1550 /* 1551 * this only happens when a client hello is received and a handshake 1552 * is started. 1553 */ 1554static int 1555have_handshake_fragment(SSL *s, int type, unsigned char *buf, 1556 int len, int peek) 1557{ 1558 1559 if ((type == SSL3_RT_HANDSHAKE) && (s->d1->handshake_fragment_len > 0)) 1560 /* (partially) satisfy request from storage */ 1561 { 1562 unsigned char *src = s->d1->handshake_fragment; 1563 unsigned char *dst = buf; 1564 unsigned int k, n; 1565 1566 /* peek == 0 */ 1567 n = 0; 1568 while ((len > 0) && (s->d1->handshake_fragment_len > 0)) { 1569 *dst++ = *src++; 1570 len--; 1571 s->d1->handshake_fragment_len--; 1572 n++; 1573 } 1574 /* move any remaining fragment bytes: */ 1575 for (k = 0; k < s->d1->handshake_fragment_len; k++) 1576 s->d1->handshake_fragment[k] = *src++; 1577 return n; 1578 } 1579 1580 return 0; 1581} 1582 1583/* 1584 * Call this to write data in records of type 'type' It will return <= 0 if 1585 * not all data has been sent or non-blocking IO. 1586 */ 1587int dtls1_write_bytes(SSL *s, int type, const void *buf, int len) 1588{ 1589 int i; 1590 1591 OPENSSL_assert(len <= SSL3_RT_MAX_PLAIN_LENGTH); 1592 s->rwstate = SSL_NOTHING; 1593 i = do_dtls1_write(s, type, buf, len, 0); 1594 return i; 1595} 1596 1597int do_dtls1_write(SSL *s, int type, const unsigned char *buf, 1598 unsigned int len, int create_empty_fragment) 1599{ 1600 unsigned char *p, *pseq; 1601 int i, mac_size, clear = 0; 1602 int prefix_len = 0; 1603 int eivlen; 1604 SSL3_RECORD *wr; 1605 SSL3_BUFFER *wb; 1606 SSL_SESSION *sess; 1607 1608 /* 1609 * first check if there is a SSL3_BUFFER still being written out. This 1610 * will happen with non blocking IO 1611 */ 1612 if (s->s3->wbuf.left != 0) { 1613 OPENSSL_assert(0); /* XDTLS: want to see if we ever get here */ 1614 return (ssl3_write_pending(s, type, buf, len)); 1615 } 1616 1617 /* If we have an alert to send, lets send it */ 1618 if (s->s3->alert_dispatch) { 1619 i = s->method->ssl_dispatch_alert(s); 1620 if (i <= 0) 1621 return (i); 1622 /* if it went, fall through and send more stuff */ 1623 } 1624 1625 if (len == 0 && !create_empty_fragment) 1626 return 0; 1627 1628 wr = &(s->s3->wrec); 1629 wb = &(s->s3->wbuf); 1630 sess = s->session; 1631 1632 if ((sess == NULL) || 1633 (s->enc_write_ctx == NULL) || (EVP_MD_CTX_md(s->write_hash) == NULL)) 1634 clear = 1; 1635 1636 if (clear) 1637 mac_size = 0; 1638 else { 1639 mac_size = EVP_MD_CTX_size(s->write_hash); 1640 if (mac_size < 0) 1641 goto err; 1642 } 1643 1644 /* DTLS implements explicit IV, so no need for empty fragments */ 1645#if 0 1646 /* 1647 * 'create_empty_fragment' is true only when this function calls itself 1648 */ 1649 if (!clear && !create_empty_fragment && !s->s3->empty_fragment_done 1650 && SSL_version(s) != DTLS1_VERSION && SSL_version(s) != DTLS1_BAD_VER) 1651 { 1652 /* 1653 * countermeasure against known-IV weakness in CBC ciphersuites (see 1654 * http://www.openssl.org/~bodo/tls-cbc.txt) 1655 */ 1656 1657 if (s->s3->need_empty_fragments && type == SSL3_RT_APPLICATION_DATA) { 1658 /* 1659 * recursive function call with 'create_empty_fragment' set; this 1660 * prepares and buffers the data for an empty fragment (these 1661 * 'prefix_len' bytes are sent out later together with the actual 1662 * payload) 1663 */ 1664 prefix_len = s->method->do_ssl_write(s, type, buf, 0, 1); 1665 if (prefix_len <= 0) 1666 goto err; 1667 1668 if (s->s3->wbuf.len < 1669 (size_t)prefix_len + SSL3_RT_MAX_PACKET_SIZE) { 1670 /* insufficient space */ 1671 SSLerr(SSL_F_DO_DTLS1_WRITE, ERR_R_INTERNAL_ERROR); 1672 goto err; 1673 } 1674 } 1675 1676 s->s3->empty_fragment_done = 1; 1677 } 1678#endif 1679 p = wb->buf + prefix_len; 1680 1681 /* write the header */ 1682 1683 *(p++) = type & 0xff; 1684 wr->type = type; 1685 /* 1686 * Special case: for hello verify request, client version 1.0 and we 1687 * haven't decided which version to use yet send back using version 1.0 1688 * header: otherwise some clients will ignore it. 1689 */ 1690 if (s->method->version == DTLS_ANY_VERSION) { 1691 *(p++) = DTLS1_VERSION >> 8; 1692 *(p++) = DTLS1_VERSION & 0xff; 1693 } else { 1694 *(p++) = s->version >> 8; 1695 *(p++) = s->version & 0xff; 1696 } 1697 1698 /* field where we are to write out packet epoch, seq num and len */ 1699 pseq = p; 1700 p += 10; 1701 1702 /* Explicit IV length, block ciphers appropriate version flag */ 1703 if (s->enc_write_ctx) { 1704 int mode = EVP_CIPHER_CTX_mode(s->enc_write_ctx); 1705 if (mode == EVP_CIPH_CBC_MODE) { 1706 eivlen = EVP_CIPHER_CTX_iv_length(s->enc_write_ctx); 1707 if (eivlen <= 1) 1708 eivlen = 0; 1709 } 1710 /* Need explicit part of IV for GCM mode */ 1711 else if (mode == EVP_CIPH_GCM_MODE) 1712 eivlen = EVP_GCM_TLS_EXPLICIT_IV_LEN; 1713 else 1714 eivlen = 0; 1715 } else 1716 eivlen = 0; 1717 1718 /* lets setup the record stuff. */ 1719 wr->data = p + eivlen; /* make room for IV in case of CBC */ 1720 wr->length = (int)len; 1721 wr->input = (unsigned char *)buf; 1722 1723 /* 1724 * we now 'read' from wr->input, wr->length bytes into wr->data 1725 */ 1726 1727 /* first we compress */ 1728 if (s->compress != NULL) { 1729 if (!ssl3_do_compress(s)) { 1730 SSLerr(SSL_F_DO_DTLS1_WRITE, SSL_R_COMPRESSION_FAILURE); 1731 goto err; 1732 } 1733 } else { 1734 memcpy(wr->data, wr->input, wr->length); 1735 wr->input = wr->data; 1736 } 1737 1738 /* 1739 * we should still have the output to wr->data and the input from 1740 * wr->input. Length should be wr->length. wr->data still points in the 1741 * wb->buf 1742 */ 1743 1744 if (mac_size != 0) { 1745 if (s->method->ssl3_enc->mac(s, &(p[wr->length + eivlen]), 1) < 0) 1746 goto err; 1747 wr->length += mac_size; 1748 } 1749 1750 /* this is true regardless of mac size */ 1751 wr->input = p; 1752 wr->data = p; 1753 1754 if (eivlen) 1755 wr->length += eivlen; 1756 1757 if (s->method->ssl3_enc->enc(s, 1) < 1) 1758 goto err; 1759 1760 /* record length after mac and block padding */ 1761 /* 1762 * if (type == SSL3_RT_APPLICATION_DATA || (type == SSL3_RT_ALERT && ! 1763 * SSL_in_init(s))) 1764 */ 1765 1766 /* there's only one epoch between handshake and app data */ 1767 1768 s2n(s->d1->w_epoch, pseq); 1769 1770 /* XDTLS: ?? */ 1771 /* 1772 * else s2n(s->d1->handshake_epoch, pseq); 1773 */ 1774 1775 memcpy(pseq, &(s->s3->write_sequence[2]), 6); 1776 pseq += 6; 1777 s2n(wr->length, pseq); 1778 1779 if (s->msg_callback) 1780 s->msg_callback(1, 0, SSL3_RT_HEADER, pseq - DTLS1_RT_HEADER_LENGTH, 1781 DTLS1_RT_HEADER_LENGTH, s, s->msg_callback_arg); 1782 1783 /* 1784 * we should now have wr->data pointing to the encrypted data, which is 1785 * wr->length long 1786 */ 1787 wr->type = type; /* not needed but helps for debugging */ 1788 wr->length += DTLS1_RT_HEADER_LENGTH; 1789 1790#if 0 /* this is now done at the message layer */ 1791 /* buffer the record, making it easy to handle retransmits */ 1792 if (type == SSL3_RT_HANDSHAKE || type == SSL3_RT_CHANGE_CIPHER_SPEC) 1793 dtls1_buffer_record(s, wr->data, wr->length, 1794 *((PQ_64BIT *) & (s->s3->write_sequence[0]))); 1795#endif 1796 1797 ssl3_record_sequence_update(&(s->s3->write_sequence[0])); 1798 1799 if (create_empty_fragment) { 1800 /* 1801 * we are in a recursive call; just return the length, don't write 1802 * out anything here 1803 */ 1804 return wr->length; 1805 } 1806 1807 /* now let's set up wb */ 1808 wb->left = prefix_len + wr->length; 1809 wb->offset = 0; 1810 1811 /* 1812 * memorize arguments so that ssl3_write_pending can detect bad write 1813 * retries later 1814 */ 1815 s->s3->wpend_tot = len; 1816 s->s3->wpend_buf = buf; 1817 s->s3->wpend_type = type; 1818 s->s3->wpend_ret = len; 1819 1820 /* we now just need to write the buffer */ 1821 return ssl3_write_pending(s, type, buf, len); 1822 err: 1823 return -1; 1824} 1825 1826static int dtls1_record_replay_check(SSL *s, DTLS1_BITMAP *bitmap) 1827{ 1828 int cmp; 1829 unsigned int shift; 1830 const unsigned char *seq = s->s3->read_sequence; 1831 1832 cmp = satsub64be(seq, bitmap->max_seq_num); 1833 if (cmp > 0) { 1834 memcpy(s->s3->rrec.seq_num, seq, 8); 1835 return 1; /* this record in new */ 1836 } 1837 shift = -cmp; 1838 if (shift >= sizeof(bitmap->map) * 8) 1839 return 0; /* stale, outside the window */ 1840 else if (bitmap->map & (1UL << shift)) 1841 return 0; /* record previously received */ 1842 1843 memcpy(s->s3->rrec.seq_num, seq, 8); 1844 return 1; 1845} 1846 1847static void dtls1_record_bitmap_update(SSL *s, DTLS1_BITMAP *bitmap) 1848{ 1849 int cmp; 1850 unsigned int shift; 1851 const unsigned char *seq = s->s3->read_sequence; 1852 1853 cmp = satsub64be(seq, bitmap->max_seq_num); 1854 if (cmp > 0) { 1855 shift = cmp; 1856 if (shift < sizeof(bitmap->map) * 8) 1857 bitmap->map <<= shift, bitmap->map |= 1UL; 1858 else 1859 bitmap->map = 1UL; 1860 memcpy(bitmap->max_seq_num, seq, 8); 1861 } else { 1862 shift = -cmp; 1863 if (shift < sizeof(bitmap->map) * 8) 1864 bitmap->map |= 1UL << shift; 1865 } 1866} 1867 1868int dtls1_dispatch_alert(SSL *s) 1869{ 1870 int i, j; 1871 void (*cb) (const SSL *ssl, int type, int val) = NULL; 1872 unsigned char buf[DTLS1_AL_HEADER_LENGTH]; 1873 unsigned char *ptr = &buf[0]; 1874 1875 s->s3->alert_dispatch = 0; 1876 1877 memset(buf, 0x00, sizeof(buf)); 1878 *ptr++ = s->s3->send_alert[0]; 1879 *ptr++ = s->s3->send_alert[1]; 1880 1881#ifdef DTLS1_AD_MISSING_HANDSHAKE_MESSAGE 1882 if (s->s3->send_alert[1] == DTLS1_AD_MISSING_HANDSHAKE_MESSAGE) { 1883 s2n(s->d1->handshake_read_seq, ptr); 1884# if 0 1885 if (s->d1->r_msg_hdr.frag_off == 0) 1886 /* 1887 * waiting for a new msg 1888 */ 1889 else 1890 s2n(s->d1->r_msg_hdr.seq, ptr); /* partial msg read */ 1891# endif 1892 1893# if 0 1894 fprintf(stderr, 1895 "s->d1->handshake_read_seq = %d, s->d1->r_msg_hdr.seq = %d\n", 1896 s->d1->handshake_read_seq, s->d1->r_msg_hdr.seq); 1897# endif 1898 l2n3(s->d1->r_msg_hdr.frag_off, ptr); 1899 } 1900#endif 1901 1902 i = do_dtls1_write(s, SSL3_RT_ALERT, &buf[0], sizeof(buf), 0); 1903 if (i <= 0) { 1904 s->s3->alert_dispatch = 1; 1905 /* fprintf( stderr, "not done with alert\n" ); */ 1906 } else { 1907 if (s->s3->send_alert[0] == SSL3_AL_FATAL 1908#ifdef DTLS1_AD_MISSING_HANDSHAKE_MESSAGE 1909 || s->s3->send_alert[1] == DTLS1_AD_MISSING_HANDSHAKE_MESSAGE 1910#endif 1911 ) 1912 (void)BIO_flush(s->wbio); 1913 1914 if (s->msg_callback) 1915 s->msg_callback(1, s->version, SSL3_RT_ALERT, s->s3->send_alert, 1916 2, s, s->msg_callback_arg); 1917 1918 if (s->info_callback != NULL) 1919 cb = s->info_callback; 1920 else if (s->ctx->info_callback != NULL) 1921 cb = s->ctx->info_callback; 1922 1923 if (cb != NULL) { 1924 j = (s->s3->send_alert[0] << 8) | s->s3->send_alert[1]; 1925 cb(s, SSL_CB_WRITE_ALERT, j); 1926 } 1927 } 1928 return (i); 1929} 1930 1931static DTLS1_BITMAP *dtls1_get_bitmap(SSL *s, SSL3_RECORD *rr, 1932 unsigned int *is_next_epoch) 1933{ 1934 1935 *is_next_epoch = 0; 1936 1937 /* In current epoch, accept HM, CCS, DATA, & ALERT */ 1938 if (rr->epoch == s->d1->r_epoch) 1939 return &s->d1->bitmap; 1940 1941 /* 1942 * Only HM and ALERT messages can be from the next epoch and only if we 1943 * have already processed all of the unprocessed records from the last 1944 * epoch 1945 */ 1946 else if (rr->epoch == (unsigned long)(s->d1->r_epoch + 1) && 1947 s->d1->unprocessed_rcds.epoch != s->d1->r_epoch && 1948 (rr->type == SSL3_RT_HANDSHAKE || rr->type == SSL3_RT_ALERT)) { 1949 *is_next_epoch = 1; 1950 return &s->d1->next_bitmap; 1951 } 1952 1953 return NULL; 1954} 1955 1956#if 0 1957static int 1958dtls1_record_needs_buffering(SSL *s, SSL3_RECORD *rr, 1959 unsigned short *priority, unsigned long *offset) 1960{ 1961 1962 /* alerts are passed up immediately */ 1963 if (rr->type == SSL3_RT_APPLICATION_DATA || rr->type == SSL3_RT_ALERT) 1964 return 0; 1965 1966 /* 1967 * Only need to buffer if a handshake is underway. (this implies that 1968 * Hello Request and Client Hello are passed up immediately) 1969 */ 1970 if (SSL_in_init(s)) { 1971 unsigned char *data = rr->data; 1972 /* need to extract the HM/CCS sequence number here */ 1973 if (rr->type == SSL3_RT_HANDSHAKE || 1974 rr->type == SSL3_RT_CHANGE_CIPHER_SPEC) { 1975 unsigned short seq_num; 1976 struct hm_header_st msg_hdr; 1977 struct ccs_header_st ccs_hdr; 1978 1979 if (rr->type == SSL3_RT_HANDSHAKE) { 1980 dtls1_get_message_header(data, &msg_hdr); 1981 seq_num = msg_hdr.seq; 1982 *offset = msg_hdr.frag_off; 1983 } else { 1984 dtls1_get_ccs_header(data, &ccs_hdr); 1985 seq_num = ccs_hdr.seq; 1986 *offset = 0; 1987 } 1988 1989 /* 1990 * this is either a record we're waiting for, or a retransmit of 1991 * something we happened to previously receive (higher layers 1992 * will drop the repeat silently 1993 */ 1994 if (seq_num < s->d1->handshake_read_seq) 1995 return 0; 1996 if (rr->type == SSL3_RT_HANDSHAKE && 1997 seq_num == s->d1->handshake_read_seq && 1998 msg_hdr.frag_off < s->d1->r_msg_hdr.frag_off) 1999 return 0; 2000 else if (seq_num == s->d1->handshake_read_seq && 2001 (rr->type == SSL3_RT_CHANGE_CIPHER_SPEC || 2002 msg_hdr.frag_off == s->d1->r_msg_hdr.frag_off)) 2003 return 0; 2004 else { 2005 *priority = seq_num; 2006 return 1; 2007 } 2008 } else /* unknown record type */ 2009 return 0; 2010 } 2011 2012 return 0; 2013} 2014#endif 2015 2016void dtls1_reset_seq_numbers(SSL *s, int rw) 2017{ 2018 unsigned char *seq; 2019 unsigned int seq_bytes = sizeof(s->s3->read_sequence); 2020 2021 if (rw & SSL3_CC_READ) { 2022 seq = s->s3->read_sequence; 2023 s->d1->r_epoch++; 2024 memcpy(&(s->d1->bitmap), &(s->d1->next_bitmap), sizeof(DTLS1_BITMAP)); 2025 memset(&(s->d1->next_bitmap), 0x00, sizeof(DTLS1_BITMAP)); 2026 2027 /* 2028 * We must not use any buffered messages received from the previous 2029 * epoch 2030 */ 2031 dtls1_clear_received_buffer(s); 2032 } else { 2033 seq = s->s3->write_sequence; 2034 memcpy(s->d1->last_write_sequence, seq, 2035 sizeof(s->s3->write_sequence)); 2036 s->d1->w_epoch++; 2037 } 2038 2039 memset(seq, 0x00, seq_bytes); 2040} 2041