d1_pkt.c revision 331638
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) 1998-2018 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 /* 710 * Lets check the version. We tolerate alerts that don't have the exact 711 * version number (e.g. because of protocol version errors) 712 */ 713 if (!s->first_packet && rr->type != SSL3_RT_ALERT) { 714 if (version != s->version) { 715 /* unexpected version, silently discard */ 716 rr->length = 0; 717 s->packet_length = 0; 718 goto again; 719 } 720 } 721 722 if ((version & 0xff00) != (s->version & 0xff00)) { 723 /* wrong version, silently discard record */ 724 rr->length = 0; 725 s->packet_length = 0; 726 goto again; 727 } 728 729 if (rr->length > SSL3_RT_MAX_ENCRYPTED_LENGTH) { 730 /* record too long, silently discard it */ 731 rr->length = 0; 732 s->packet_length = 0; 733 goto again; 734 } 735 736 /* now s->rstate == SSL_ST_READ_BODY */ 737 } 738 739 /* s->rstate == SSL_ST_READ_BODY, get and decode the data */ 740 741 if (rr->length > s->packet_length - DTLS1_RT_HEADER_LENGTH) { 742 /* now s->packet_length == DTLS1_RT_HEADER_LENGTH */ 743 i = rr->length; 744 n = ssl3_read_n(s, i, i, 1); 745 /* this packet contained a partial record, dump it */ 746 if (n != i) { 747 rr->length = 0; 748 s->packet_length = 0; 749 goto again; 750 } 751 752 /* 753 * now n == rr->length, and s->packet_length == 754 * DTLS1_RT_HEADER_LENGTH + rr->length 755 */ 756 } 757 s->rstate = SSL_ST_READ_HEADER; /* set state for later operations */ 758 759 /* match epochs. NULL means the packet is dropped on the floor */ 760 bitmap = dtls1_get_bitmap(s, rr, &is_next_epoch); 761 if (bitmap == NULL) { 762 rr->length = 0; 763 s->packet_length = 0; /* dump this record */ 764 goto again; /* get another record */ 765 } 766#ifndef OPENSSL_NO_SCTP 767 /* Only do replay check if no SCTP bio */ 768 if (!BIO_dgram_is_sctp(SSL_get_rbio(s))) { 769#endif 770 /* 771 * Check whether this is a repeat, or aged record. Don't check if 772 * we're listening and this message is a ClientHello. They can look 773 * as if they're replayed, since they arrive from different 774 * connections and would be dropped unnecessarily. 775 */ 776 if (!(s->d1->listen && rr->type == SSL3_RT_HANDSHAKE && 777 s->packet_length > DTLS1_RT_HEADER_LENGTH && 778 s->packet[DTLS1_RT_HEADER_LENGTH] == SSL3_MT_CLIENT_HELLO) && 779 !dtls1_record_replay_check(s, bitmap)) { 780 rr->length = 0; 781 s->packet_length = 0; /* dump this record */ 782 goto again; /* get another record */ 783 } 784#ifndef OPENSSL_NO_SCTP 785 } 786#endif 787 788 /* just read a 0 length packet */ 789 if (rr->length == 0) 790 goto again; 791 792 /* 793 * If this record is from the next epoch (either HM or ALERT), and a 794 * handshake is currently in progress, buffer it since it cannot be 795 * processed at this time. However, do not buffer anything while 796 * listening. 797 */ 798 if (is_next_epoch) { 799 if ((SSL_in_init(s) || s->in_handshake) && !s->d1->listen) { 800 if (dtls1_buffer_record 801 (s, &(s->d1->unprocessed_rcds), rr->seq_num) < 0) 802 return -1; 803 } 804 rr->length = 0; 805 s->packet_length = 0; 806 goto again; 807 } 808 809 if (!dtls1_process_record(s, bitmap)) { 810 rr->length = 0; 811 s->packet_length = 0; /* dump this record */ 812 goto again; /* get another record */ 813 } 814 815 return (1); 816 817} 818 819/*- 820 * Return up to 'len' payload bytes received in 'type' records. 821 * 'type' is one of the following: 822 * 823 * - SSL3_RT_HANDSHAKE (when ssl3_get_message calls us) 824 * - SSL3_RT_APPLICATION_DATA (when ssl3_read calls us) 825 * - 0 (during a shutdown, no data has to be returned) 826 * 827 * If we don't have stored data to work from, read a SSL/TLS record first 828 * (possibly multiple records if we still don't have anything to return). 829 * 830 * This function must handle any surprises the peer may have for us, such as 831 * Alert records (e.g. close_notify), ChangeCipherSpec records (not really 832 * a surprise, but handled as if it were), or renegotiation requests. 833 * Also if record payloads contain fragments too small to process, we store 834 * them until there is enough for the respective protocol (the record protocol 835 * may use arbitrary fragmentation and even interleaving): 836 * Change cipher spec protocol 837 * just 1 byte needed, no need for keeping anything stored 838 * Alert protocol 839 * 2 bytes needed (AlertLevel, AlertDescription) 840 * Handshake protocol 841 * 4 bytes needed (HandshakeType, uint24 length) -- we just have 842 * to detect unexpected Client Hello and Hello Request messages 843 * here, anything else is handled by higher layers 844 * Application data protocol 845 * none of our business 846 */ 847int dtls1_read_bytes(SSL *s, int type, unsigned char *buf, int len, int peek) 848{ 849 int al, i, j, ret; 850 unsigned int n; 851 SSL3_RECORD *rr; 852 void (*cb) (const SSL *ssl, int type2, int val) = NULL; 853 854 if (s->s3->rbuf.buf == NULL) /* Not initialized yet */ 855 if (!ssl3_setup_buffers(s)) 856 return (-1); 857 858 /* XXX: check what the second '&& type' is about */ 859 if ((type && (type != SSL3_RT_APPLICATION_DATA) && 860 (type != SSL3_RT_HANDSHAKE) && type) || 861 (peek && (type != SSL3_RT_APPLICATION_DATA))) { 862 SSLerr(SSL_F_DTLS1_READ_BYTES, ERR_R_INTERNAL_ERROR); 863 return -1; 864 } 865 866 /* 867 * check whether there's a handshake message (client hello?) waiting 868 */ 869 if ((ret = have_handshake_fragment(s, type, buf, len, peek))) 870 return ret; 871 872 /* 873 * Now s->d1->handshake_fragment_len == 0 if type == SSL3_RT_HANDSHAKE. 874 */ 875 876#ifndef OPENSSL_NO_SCTP 877 /* 878 * Continue handshake if it had to be interrupted to read app data with 879 * SCTP. 880 */ 881 if ((!s->in_handshake && SSL_in_init(s)) || 882 (BIO_dgram_is_sctp(SSL_get_rbio(s)) && 883 (s->state == DTLS1_SCTP_ST_SR_READ_SOCK 884 || s->state == DTLS1_SCTP_ST_CR_READ_SOCK) 885 && s->s3->in_read_app_data != 2)) 886#else 887 if (!s->in_handshake && SSL_in_init(s)) 888#endif 889 { 890 /* type == SSL3_RT_APPLICATION_DATA */ 891 i = s->handshake_func(s); 892 if (i < 0) 893 return (i); 894 if (i == 0) { 895 SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_R_SSL_HANDSHAKE_FAILURE); 896 return (-1); 897 } 898 } 899 900 start: 901 s->rwstate = SSL_NOTHING; 902 903 /*- 904 * s->s3->rrec.type - is the type of record 905 * s->s3->rrec.data, - data 906 * s->s3->rrec.off, - offset into 'data' for next read 907 * s->s3->rrec.length, - number of bytes. 908 */ 909 rr = &(s->s3->rrec); 910 911 /* 912 * We are not handshaking and have no data yet, so process data buffered 913 * during the last handshake in advance, if any. 914 */ 915 if (s->state == SSL_ST_OK && rr->length == 0) { 916 pitem *item; 917 item = pqueue_pop(s->d1->buffered_app_data.q); 918 if (item) { 919#ifndef OPENSSL_NO_SCTP 920 /* Restore bio_dgram_sctp_rcvinfo struct */ 921 if (BIO_dgram_is_sctp(SSL_get_rbio(s))) { 922 DTLS1_RECORD_DATA *rdata = (DTLS1_RECORD_DATA *)item->data; 923 BIO_ctrl(SSL_get_rbio(s), BIO_CTRL_DGRAM_SCTP_SET_RCVINFO, 924 sizeof(rdata->recordinfo), &rdata->recordinfo); 925 } 926#endif 927 928 dtls1_copy_record(s, item); 929 930 OPENSSL_free(item->data); 931 pitem_free(item); 932 } 933 } 934 935 /* Check for timeout */ 936 if (dtls1_handle_timeout(s) > 0) 937 goto start; 938 939 /* get new packet if necessary */ 940 if ((rr->length == 0) || (s->rstate == SSL_ST_READ_BODY)) { 941 ret = dtls1_get_record(s); 942 if (ret <= 0) { 943 ret = dtls1_read_failed(s, ret); 944 /* anything other than a timeout is an error */ 945 if (ret <= 0) 946 return (ret); 947 else 948 goto start; 949 } 950 } 951 952 if (s->d1->listen && rr->type != SSL3_RT_HANDSHAKE) { 953 rr->length = 0; 954 goto start; 955 } 956 957 /* 958 * Reset the count of consecutive warning alerts if we've got a non-empty 959 * record that isn't an alert. 960 */ 961 if (rr->type != SSL3_RT_ALERT && rr->length != 0) 962 s->cert->alert_count = 0; 963 964 /* we now have a packet which can be read and processed */ 965 966 if (s->s3->change_cipher_spec /* set when we receive ChangeCipherSpec, 967 * reset by ssl3_get_finished */ 968 && (rr->type != SSL3_RT_HANDSHAKE)) { 969 /* 970 * We now have application data between CCS and Finished. Most likely 971 * the packets were reordered on their way, so buffer the application 972 * data for later processing rather than dropping the connection. 973 */ 974 if (dtls1_buffer_record(s, &(s->d1->buffered_app_data), rr->seq_num) < 975 0) { 976 SSLerr(SSL_F_DTLS1_READ_BYTES, ERR_R_INTERNAL_ERROR); 977 return -1; 978 } 979 rr->length = 0; 980 goto start; 981 } 982 983 /* 984 * If the other end has shut down, throw anything we read away (even in 985 * 'peek' mode) 986 */ 987 if (s->shutdown & SSL_RECEIVED_SHUTDOWN) { 988 rr->length = 0; 989 s->rwstate = SSL_NOTHING; 990 return (0); 991 } 992 993 if (type == rr->type) { /* SSL3_RT_APPLICATION_DATA or 994 * SSL3_RT_HANDSHAKE */ 995 /* 996 * make sure that we are not getting application data when we are 997 * doing a handshake for the first time 998 */ 999 if (SSL_in_init(s) && (type == SSL3_RT_APPLICATION_DATA) && 1000 (s->enc_read_ctx == NULL)) { 1001 al = SSL_AD_UNEXPECTED_MESSAGE; 1002 SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_R_APP_DATA_IN_HANDSHAKE); 1003 goto f_err; 1004 } 1005 1006 if (len <= 0) 1007 return (len); 1008 1009 if ((unsigned int)len > rr->length) 1010 n = rr->length; 1011 else 1012 n = (unsigned int)len; 1013 1014 memcpy(buf, &(rr->data[rr->off]), n); 1015 if (!peek) { 1016 rr->length -= n; 1017 rr->off += n; 1018 if (rr->length == 0) { 1019 s->rstate = SSL_ST_READ_HEADER; 1020 rr->off = 0; 1021 } 1022 } 1023#ifndef OPENSSL_NO_SCTP 1024 /* 1025 * We were about to renegotiate but had to read belated application 1026 * data first, so retry. 1027 */ 1028 if (BIO_dgram_is_sctp(SSL_get_rbio(s)) && 1029 rr->type == SSL3_RT_APPLICATION_DATA && 1030 (s->state == DTLS1_SCTP_ST_SR_READ_SOCK 1031 || s->state == DTLS1_SCTP_ST_CR_READ_SOCK)) { 1032 s->rwstate = SSL_READING; 1033 BIO_clear_retry_flags(SSL_get_rbio(s)); 1034 BIO_set_retry_read(SSL_get_rbio(s)); 1035 } 1036 1037 /* 1038 * We might had to delay a close_notify alert because of reordered 1039 * app data. If there was an alert and there is no message to read 1040 * anymore, finally set shutdown. 1041 */ 1042 if (BIO_dgram_is_sctp(SSL_get_rbio(s)) && 1043 s->d1->shutdown_received 1044 && !BIO_dgram_sctp_msg_waiting(SSL_get_rbio(s))) { 1045 s->shutdown |= SSL_RECEIVED_SHUTDOWN; 1046 return (0); 1047 } 1048#endif 1049 return (n); 1050 } 1051 1052 /* 1053 * If we get here, then type != rr->type; if we have a handshake message, 1054 * then it was unexpected (Hello Request or Client Hello). 1055 */ 1056 1057 /* 1058 * In case of record types for which we have 'fragment' storage, fill 1059 * that so that we can process the data at a fixed place. 1060 */ 1061 { 1062 unsigned int k, dest_maxlen = 0; 1063 unsigned char *dest = NULL; 1064 unsigned int *dest_len = NULL; 1065 1066 if (rr->type == SSL3_RT_HANDSHAKE) { 1067 dest_maxlen = sizeof(s->d1->handshake_fragment); 1068 dest = s->d1->handshake_fragment; 1069 dest_len = &s->d1->handshake_fragment_len; 1070 } else if (rr->type == SSL3_RT_ALERT) { 1071 dest_maxlen = sizeof(s->d1->alert_fragment); 1072 dest = s->d1->alert_fragment; 1073 dest_len = &s->d1->alert_fragment_len; 1074 } 1075#ifndef OPENSSL_NO_HEARTBEATS 1076 else if (rr->type == TLS1_RT_HEARTBEAT) { 1077 dtls1_process_heartbeat(s); 1078 1079 /* Exit and notify application to read again */ 1080 rr->length = 0; 1081 s->rwstate = SSL_READING; 1082 BIO_clear_retry_flags(SSL_get_rbio(s)); 1083 BIO_set_retry_read(SSL_get_rbio(s)); 1084 return (-1); 1085 } 1086#endif 1087 /* else it's a CCS message, or application data or wrong */ 1088 else if (rr->type != SSL3_RT_CHANGE_CIPHER_SPEC) { 1089 /* 1090 * Application data while renegotiating is allowed. Try again 1091 * reading. 1092 */ 1093 if (rr->type == SSL3_RT_APPLICATION_DATA) { 1094 BIO *bio; 1095 s->s3->in_read_app_data = 2; 1096 bio = SSL_get_rbio(s); 1097 s->rwstate = SSL_READING; 1098 BIO_clear_retry_flags(bio); 1099 BIO_set_retry_read(bio); 1100 return (-1); 1101 } 1102 1103 /* Not certain if this is the right error handling */ 1104 al = SSL_AD_UNEXPECTED_MESSAGE; 1105 SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_R_UNEXPECTED_RECORD); 1106 goto f_err; 1107 } 1108 1109 if (dest_maxlen > 0) { 1110 /* 1111 * XDTLS: In a pathalogical case, the Client Hello may be 1112 * fragmented--don't always expect dest_maxlen bytes 1113 */ 1114 if (rr->length < dest_maxlen) { 1115#ifdef DTLS1_AD_MISSING_HANDSHAKE_MESSAGE 1116 /* 1117 * for normal alerts rr->length is 2, while 1118 * dest_maxlen is 7 if we were to handle this 1119 * non-existing alert... 1120 */ 1121 FIX ME 1122#endif 1123 s->rstate = SSL_ST_READ_HEADER; 1124 rr->length = 0; 1125 goto start; 1126 } 1127 1128 /* now move 'n' bytes: */ 1129 for (k = 0; k < dest_maxlen; k++) { 1130 dest[k] = rr->data[rr->off++]; 1131 rr->length--; 1132 } 1133 *dest_len = dest_maxlen; 1134 } 1135 } 1136 1137 /*- 1138 * s->d1->handshake_fragment_len == 12 iff rr->type == SSL3_RT_HANDSHAKE; 1139 * s->d1->alert_fragment_len == 7 iff rr->type == SSL3_RT_ALERT. 1140 * (Possibly rr is 'empty' now, i.e. rr->length may be 0.) 1141 */ 1142 1143 /* If we are a client, check for an incoming 'Hello Request': */ 1144 if ((!s->server) && 1145 (s->d1->handshake_fragment_len >= DTLS1_HM_HEADER_LENGTH) && 1146 (s->d1->handshake_fragment[0] == SSL3_MT_HELLO_REQUEST) && 1147 (s->session != NULL) && (s->session->cipher != NULL)) { 1148 s->d1->handshake_fragment_len = 0; 1149 1150 if ((s->d1->handshake_fragment[1] != 0) || 1151 (s->d1->handshake_fragment[2] != 0) || 1152 (s->d1->handshake_fragment[3] != 0)) { 1153 al = SSL_AD_DECODE_ERROR; 1154 SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_R_BAD_HELLO_REQUEST); 1155 goto f_err; 1156 } 1157 1158 /* 1159 * no need to check sequence number on HELLO REQUEST messages 1160 */ 1161 1162 if (s->msg_callback) 1163 s->msg_callback(0, s->version, SSL3_RT_HANDSHAKE, 1164 s->d1->handshake_fragment, 4, s, 1165 s->msg_callback_arg); 1166 1167 if (SSL_is_init_finished(s) && 1168 !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS) && 1169 !s->s3->renegotiate) { 1170 s->d1->handshake_read_seq++; 1171 s->new_session = 1; 1172 ssl3_renegotiate(s); 1173 if (ssl3_renegotiate_check(s)) { 1174 i = s->handshake_func(s); 1175 if (i < 0) 1176 return (i); 1177 if (i == 0) { 1178 SSLerr(SSL_F_DTLS1_READ_BYTES, 1179 SSL_R_SSL_HANDSHAKE_FAILURE); 1180 return (-1); 1181 } 1182 1183 if (!(s->mode & SSL_MODE_AUTO_RETRY)) { 1184 if (s->s3->rbuf.left == 0) { /* no read-ahead left? */ 1185 BIO *bio; 1186 /* 1187 * In the case where we try to read application data, 1188 * but we trigger an SSL handshake, we return -1 with 1189 * the retry option set. Otherwise renegotiation may 1190 * cause nasty problems in the blocking world 1191 */ 1192 s->rwstate = SSL_READING; 1193 bio = SSL_get_rbio(s); 1194 BIO_clear_retry_flags(bio); 1195 BIO_set_retry_read(bio); 1196 return (-1); 1197 } 1198 } 1199 } 1200 } 1201 /* 1202 * we either finished a handshake or ignored the request, now try 1203 * again to obtain the (application) data we were asked for 1204 */ 1205 goto start; 1206 } 1207 1208 /* 1209 * If we are a server and get a client hello when renegotiation isn't 1210 * allowed send back a no renegotiation alert and carry on. 1211 */ 1212 if (s->server 1213 && SSL_is_init_finished(s) 1214 && !s->s3->send_connection_binding 1215 && s->d1->handshake_fragment_len >= DTLS1_HM_HEADER_LENGTH 1216 && s->d1->handshake_fragment[0] == SSL3_MT_CLIENT_HELLO 1217 && s->s3->previous_client_finished_len != 0 1218 && (s->options & SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION) == 0) { 1219 s->d1->handshake_fragment_len = 0; 1220 rr->length = 0; 1221 ssl3_send_alert(s, SSL3_AL_WARNING, SSL_AD_NO_RENEGOTIATION); 1222 goto start; 1223 } 1224 1225 1226 if (s->d1->alert_fragment_len >= DTLS1_AL_HEADER_LENGTH) { 1227 int alert_level = s->d1->alert_fragment[0]; 1228 int alert_descr = s->d1->alert_fragment[1]; 1229 1230 s->d1->alert_fragment_len = 0; 1231 1232 if (s->msg_callback) 1233 s->msg_callback(0, s->version, SSL3_RT_ALERT, 1234 s->d1->alert_fragment, 2, s, s->msg_callback_arg); 1235 1236 if (s->info_callback != NULL) 1237 cb = s->info_callback; 1238 else if (s->ctx->info_callback != NULL) 1239 cb = s->ctx->info_callback; 1240 1241 if (cb != NULL) { 1242 j = (alert_level << 8) | alert_descr; 1243 cb(s, SSL_CB_READ_ALERT, j); 1244 } 1245 1246 if (alert_level == SSL3_AL_WARNING) { 1247 s->s3->warn_alert = alert_descr; 1248 1249 s->cert->alert_count++; 1250 if (s->cert->alert_count == MAX_WARN_ALERT_COUNT) { 1251 al = SSL_AD_UNEXPECTED_MESSAGE; 1252 SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_R_TOO_MANY_WARN_ALERTS); 1253 goto f_err; 1254 } 1255 1256 if (alert_descr == SSL_AD_CLOSE_NOTIFY) { 1257#ifndef OPENSSL_NO_SCTP 1258 /* 1259 * With SCTP and streams the socket may deliver app data 1260 * after a close_notify alert. We have to check this first so 1261 * that nothing gets discarded. 1262 */ 1263 if (BIO_dgram_is_sctp(SSL_get_rbio(s)) && 1264 BIO_dgram_sctp_msg_waiting(SSL_get_rbio(s))) { 1265 s->d1->shutdown_received = 1; 1266 s->rwstate = SSL_READING; 1267 BIO_clear_retry_flags(SSL_get_rbio(s)); 1268 BIO_set_retry_read(SSL_get_rbio(s)); 1269 return -1; 1270 } 1271#endif 1272 s->shutdown |= SSL_RECEIVED_SHUTDOWN; 1273 return (0); 1274 } 1275#if 0 1276 /* XXX: this is a possible improvement in the future */ 1277 /* now check if it's a missing record */ 1278 if (alert_descr == DTLS1_AD_MISSING_HANDSHAKE_MESSAGE) { 1279 unsigned short seq; 1280 unsigned int frag_off; 1281 unsigned char *p = &(s->d1->alert_fragment[2]); 1282 1283 n2s(p, seq); 1284 n2l3(p, frag_off); 1285 1286 dtls1_retransmit_message(s, 1287 dtls1_get_queue_priority 1288 (frag->msg_header.seq, 0), frag_off, 1289 &found); 1290 if (!found && SSL_in_init(s)) { 1291 /* 1292 * fprintf( stderr,"in init = %d\n", SSL_in_init(s)); 1293 */ 1294 /* 1295 * requested a message not yet sent, send an alert 1296 * ourselves 1297 */ 1298 ssl3_send_alert(s, SSL3_AL_WARNING, 1299 DTLS1_AD_MISSING_HANDSHAKE_MESSAGE); 1300 } 1301 } 1302#endif 1303 } else if (alert_level == SSL3_AL_FATAL) { 1304 char tmp[16]; 1305 1306 s->rwstate = SSL_NOTHING; 1307 s->s3->fatal_alert = alert_descr; 1308 SSLerr(SSL_F_DTLS1_READ_BYTES, 1309 SSL_AD_REASON_OFFSET + alert_descr); 1310 BIO_snprintf(tmp, sizeof(tmp), "%d", alert_descr); 1311 ERR_add_error_data(2, "SSL alert number ", tmp); 1312 s->shutdown |= SSL_RECEIVED_SHUTDOWN; 1313 SSL_CTX_remove_session(s->session_ctx, s->session); 1314 return (0); 1315 } else { 1316 al = SSL_AD_ILLEGAL_PARAMETER; 1317 SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_R_UNKNOWN_ALERT_TYPE); 1318 goto f_err; 1319 } 1320 1321 goto start; 1322 } 1323 1324 if (s->shutdown & SSL_SENT_SHUTDOWN) { /* but we have not received a 1325 * shutdown */ 1326 s->rwstate = SSL_NOTHING; 1327 rr->length = 0; 1328 return (0); 1329 } 1330 1331 if (rr->type == SSL3_RT_CHANGE_CIPHER_SPEC) { 1332 struct ccs_header_st ccs_hdr; 1333 unsigned int ccs_hdr_len = DTLS1_CCS_HEADER_LENGTH; 1334 1335 dtls1_get_ccs_header(rr->data, &ccs_hdr); 1336 1337 if (s->version == DTLS1_BAD_VER) 1338 ccs_hdr_len = 3; 1339 1340 /* 1341 * 'Change Cipher Spec' is just a single byte, so we know exactly 1342 * what the record payload has to look like 1343 */ 1344 /* XDTLS: check that epoch is consistent */ 1345 if ((rr->length != ccs_hdr_len) || 1346 (rr->off != 0) || (rr->data[0] != SSL3_MT_CCS)) { 1347 al = SSL_AD_ILLEGAL_PARAMETER; 1348 SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_R_BAD_CHANGE_CIPHER_SPEC); 1349 goto f_err; 1350 } 1351 1352 rr->length = 0; 1353 1354 if (s->msg_callback) 1355 s->msg_callback(0, s->version, SSL3_RT_CHANGE_CIPHER_SPEC, 1356 rr->data, 1, s, s->msg_callback_arg); 1357 1358 /* 1359 * We can't process a CCS now, because previous handshake messages 1360 * are still missing, so just drop it. 1361 */ 1362 if (!s->d1->change_cipher_spec_ok) { 1363 goto start; 1364 } 1365 1366 s->d1->change_cipher_spec_ok = 0; 1367 1368 s->s3->change_cipher_spec = 1; 1369 if (!ssl3_do_change_cipher_spec(s)) 1370 goto err; 1371 1372 /* do this whenever CCS is processed */ 1373 dtls1_reset_seq_numbers(s, SSL3_CC_READ); 1374 1375 if (s->version == DTLS1_BAD_VER) 1376 s->d1->handshake_read_seq++; 1377 1378#ifndef OPENSSL_NO_SCTP 1379 /* 1380 * Remember that a CCS has been received, so that an old key of 1381 * SCTP-Auth can be deleted when a CCS is sent. Will be ignored if no 1382 * SCTP is used 1383 */ 1384 BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_AUTH_CCS_RCVD, 1, NULL); 1385#endif 1386 1387 goto start; 1388 } 1389 1390 /* 1391 * Unexpected handshake message (Client Hello, or protocol violation) 1392 */ 1393 if ((s->d1->handshake_fragment_len >= DTLS1_HM_HEADER_LENGTH) && 1394 !s->in_handshake) { 1395 struct hm_header_st msg_hdr; 1396 1397 /* this may just be a stale retransmit */ 1398 dtls1_get_message_header(rr->data, &msg_hdr); 1399 if (rr->epoch != s->d1->r_epoch) { 1400 rr->length = 0; 1401 goto start; 1402 } 1403 1404 /* 1405 * If we are server, we may have a repeated FINISHED of the client 1406 * here, then retransmit our CCS and FINISHED. 1407 */ 1408 if (msg_hdr.type == SSL3_MT_FINISHED) { 1409 if (dtls1_check_timeout_num(s) < 0) 1410 return -1; 1411 1412 dtls1_retransmit_buffered_messages(s); 1413 rr->length = 0; 1414 goto start; 1415 } 1416 1417 if (((s->state & SSL_ST_MASK) == SSL_ST_OK) && 1418 !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS)) { 1419#if 0 /* worked only because C operator preferences 1420 * are not as expected (and because this is 1421 * not really needed for clients except for 1422 * detecting protocol violations): */ 1423 s->state = SSL_ST_BEFORE | (s->server) 1424 ? SSL_ST_ACCEPT : SSL_ST_CONNECT; 1425#else 1426 s->state = s->server ? SSL_ST_ACCEPT : SSL_ST_CONNECT; 1427#endif 1428 s->renegotiate = 1; 1429 s->new_session = 1; 1430 } 1431 i = s->handshake_func(s); 1432 if (i < 0) 1433 return (i); 1434 if (i == 0) { 1435 SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_R_SSL_HANDSHAKE_FAILURE); 1436 return (-1); 1437 } 1438 1439 if (!(s->mode & SSL_MODE_AUTO_RETRY)) { 1440 if (s->s3->rbuf.left == 0) { /* no read-ahead left? */ 1441 BIO *bio; 1442 /* 1443 * In the case where we try to read application data, but we 1444 * trigger an SSL handshake, we return -1 with the retry 1445 * option set. Otherwise renegotiation may cause nasty 1446 * problems in the blocking world 1447 */ 1448 s->rwstate = SSL_READING; 1449 bio = SSL_get_rbio(s); 1450 BIO_clear_retry_flags(bio); 1451 BIO_set_retry_read(bio); 1452 return (-1); 1453 } 1454 } 1455 goto start; 1456 } 1457 1458 switch (rr->type) { 1459 default: 1460#ifndef OPENSSL_NO_TLS 1461 /* TLS just ignores unknown message types */ 1462 if (s->version == TLS1_VERSION) { 1463 rr->length = 0; 1464 goto start; 1465 } 1466#endif 1467 al = SSL_AD_UNEXPECTED_MESSAGE; 1468 SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_R_UNEXPECTED_RECORD); 1469 goto f_err; 1470 case SSL3_RT_CHANGE_CIPHER_SPEC: 1471 case SSL3_RT_ALERT: 1472 case SSL3_RT_HANDSHAKE: 1473 /* 1474 * we already handled all of these, with the possible exception of 1475 * SSL3_RT_HANDSHAKE when s->in_handshake is set, but that should not 1476 * happen when type != rr->type 1477 */ 1478 al = SSL_AD_UNEXPECTED_MESSAGE; 1479 SSLerr(SSL_F_DTLS1_READ_BYTES, ERR_R_INTERNAL_ERROR); 1480 goto f_err; 1481 case SSL3_RT_APPLICATION_DATA: 1482 /* 1483 * At this point, we were expecting handshake data, but have 1484 * application data. If the library was running inside ssl3_read() 1485 * (i.e. in_read_app_data is set) and it makes sense to read 1486 * application data at this point (session renegotiation not yet 1487 * started), we will indulge it. 1488 */ 1489 if (s->s3->in_read_app_data && 1490 (s->s3->total_renegotiations != 0) && 1491 (((s->state & SSL_ST_CONNECT) && 1492 (s->state >= SSL3_ST_CW_CLNT_HELLO_A) && 1493 (s->state <= SSL3_ST_CR_SRVR_HELLO_A) 1494 ) || ((s->state & SSL_ST_ACCEPT) && 1495 (s->state <= SSL3_ST_SW_HELLO_REQ_A) && 1496 (s->state >= SSL3_ST_SR_CLNT_HELLO_A) 1497 ) 1498 )) { 1499 s->s3->in_read_app_data = 2; 1500 return (-1); 1501 } else { 1502 al = SSL_AD_UNEXPECTED_MESSAGE; 1503 SSLerr(SSL_F_DTLS1_READ_BYTES, SSL_R_UNEXPECTED_RECORD); 1504 goto f_err; 1505 } 1506 } 1507 /* not reached */ 1508 1509 f_err: 1510 ssl3_send_alert(s, SSL3_AL_FATAL, al); 1511 err: 1512 return (-1); 1513} 1514 1515int dtls1_write_app_data_bytes(SSL *s, int type, const void *buf_, int len) 1516{ 1517 int i; 1518 1519#ifndef OPENSSL_NO_SCTP 1520 /* 1521 * Check if we have to continue an interrupted handshake for reading 1522 * belated app data with SCTP. 1523 */ 1524 if ((SSL_in_init(s) && !s->in_handshake) || 1525 (BIO_dgram_is_sctp(SSL_get_wbio(s)) && 1526 (s->state == DTLS1_SCTP_ST_SR_READ_SOCK 1527 || s->state == DTLS1_SCTP_ST_CR_READ_SOCK))) 1528#else 1529 if (SSL_in_init(s) && !s->in_handshake) 1530#endif 1531 { 1532 i = s->handshake_func(s); 1533 if (i < 0) 1534 return (i); 1535 if (i == 0) { 1536 SSLerr(SSL_F_DTLS1_WRITE_APP_DATA_BYTES, 1537 SSL_R_SSL_HANDSHAKE_FAILURE); 1538 return -1; 1539 } 1540 } 1541 1542 if (len > SSL3_RT_MAX_PLAIN_LENGTH) { 1543 SSLerr(SSL_F_DTLS1_WRITE_APP_DATA_BYTES, SSL_R_DTLS_MESSAGE_TOO_BIG); 1544 return -1; 1545 } 1546 1547 i = dtls1_write_bytes(s, type, buf_, len); 1548 return i; 1549} 1550 1551 /* 1552 * this only happens when a client hello is received and a handshake 1553 * is started. 1554 */ 1555static int 1556have_handshake_fragment(SSL *s, int type, unsigned char *buf, 1557 int len, int peek) 1558{ 1559 1560 if ((type == SSL3_RT_HANDSHAKE) && (s->d1->handshake_fragment_len > 0)) 1561 /* (partially) satisfy request from storage */ 1562 { 1563 unsigned char *src = s->d1->handshake_fragment; 1564 unsigned char *dst = buf; 1565 unsigned int k, n; 1566 1567 /* peek == 0 */ 1568 n = 0; 1569 while ((len > 0) && (s->d1->handshake_fragment_len > 0)) { 1570 *dst++ = *src++; 1571 len--; 1572 s->d1->handshake_fragment_len--; 1573 n++; 1574 } 1575 /* move any remaining fragment bytes: */ 1576 for (k = 0; k < s->d1->handshake_fragment_len; k++) 1577 s->d1->handshake_fragment[k] = *src++; 1578 return n; 1579 } 1580 1581 return 0; 1582} 1583 1584/* 1585 * Call this to write data in records of type 'type' It will return <= 0 if 1586 * not all data has been sent or non-blocking IO. 1587 */ 1588int dtls1_write_bytes(SSL *s, int type, const void *buf, int len) 1589{ 1590 int i; 1591 1592 OPENSSL_assert(len <= SSL3_RT_MAX_PLAIN_LENGTH); 1593 s->rwstate = SSL_NOTHING; 1594 i = do_dtls1_write(s, type, buf, len, 0); 1595 return i; 1596} 1597 1598int do_dtls1_write(SSL *s, int type, const unsigned char *buf, 1599 unsigned int len, int create_empty_fragment) 1600{ 1601 unsigned char *p, *pseq; 1602 int i, mac_size, clear = 0; 1603 int prefix_len = 0; 1604 int eivlen; 1605 SSL3_RECORD *wr; 1606 SSL3_BUFFER *wb; 1607 SSL_SESSION *sess; 1608 1609 /* 1610 * first check if there is a SSL3_BUFFER still being written out. This 1611 * will happen with non blocking IO 1612 */ 1613 if (s->s3->wbuf.left != 0) { 1614 OPENSSL_assert(0); /* XDTLS: want to see if we ever get here */ 1615 return (ssl3_write_pending(s, type, buf, len)); 1616 } 1617 1618 /* If we have an alert to send, lets send it */ 1619 if (s->s3->alert_dispatch) { 1620 i = s->method->ssl_dispatch_alert(s); 1621 if (i <= 0) 1622 return (i); 1623 /* if it went, fall through and send more stuff */ 1624 } 1625 1626 if (len == 0 && !create_empty_fragment) 1627 return 0; 1628 1629 wr = &(s->s3->wrec); 1630 wb = &(s->s3->wbuf); 1631 sess = s->session; 1632 1633 if ((sess == NULL) || 1634 (s->enc_write_ctx == NULL) || (EVP_MD_CTX_md(s->write_hash) == NULL)) 1635 clear = 1; 1636 1637 if (clear) 1638 mac_size = 0; 1639 else { 1640 mac_size = EVP_MD_CTX_size(s->write_hash); 1641 if (mac_size < 0) 1642 goto err; 1643 } 1644 1645 /* DTLS implements explicit IV, so no need for empty fragments */ 1646#if 0 1647 /* 1648 * 'create_empty_fragment' is true only when this function calls itself 1649 */ 1650 if (!clear && !create_empty_fragment && !s->s3->empty_fragment_done 1651 && SSL_version(s) != DTLS1_VERSION && SSL_version(s) != DTLS1_BAD_VER) 1652 { 1653 /* 1654 * countermeasure against known-IV weakness in CBC ciphersuites (see 1655 * http://www.openssl.org/~bodo/tls-cbc.txt) 1656 */ 1657 1658 if (s->s3->need_empty_fragments && type == SSL3_RT_APPLICATION_DATA) { 1659 /* 1660 * recursive function call with 'create_empty_fragment' set; this 1661 * prepares and buffers the data for an empty fragment (these 1662 * 'prefix_len' bytes are sent out later together with the actual 1663 * payload) 1664 */ 1665 prefix_len = s->method->do_ssl_write(s, type, buf, 0, 1); 1666 if (prefix_len <= 0) 1667 goto err; 1668 1669 if (s->s3->wbuf.len < 1670 (size_t)prefix_len + SSL3_RT_MAX_PACKET_SIZE) { 1671 /* insufficient space */ 1672 SSLerr(SSL_F_DO_DTLS1_WRITE, ERR_R_INTERNAL_ERROR); 1673 goto err; 1674 } 1675 } 1676 1677 s->s3->empty_fragment_done = 1; 1678 } 1679#endif 1680 p = wb->buf + prefix_len; 1681 1682 /* write the header */ 1683 1684 *(p++) = type & 0xff; 1685 wr->type = type; 1686 /* 1687 * Special case: for hello verify request, client version 1.0 and we 1688 * haven't decided which version to use yet send back using version 1.0 1689 * header: otherwise some clients will ignore it. 1690 */ 1691 if (s->method->version == DTLS_ANY_VERSION) { 1692 *(p++) = DTLS1_VERSION >> 8; 1693 *(p++) = DTLS1_VERSION & 0xff; 1694 } else { 1695 *(p++) = s->version >> 8; 1696 *(p++) = s->version & 0xff; 1697 } 1698 1699 /* field where we are to write out packet epoch, seq num and len */ 1700 pseq = p; 1701 p += 10; 1702 1703 /* Explicit IV length, block ciphers appropriate version flag */ 1704 if (s->enc_write_ctx) { 1705 int mode = EVP_CIPHER_CTX_mode(s->enc_write_ctx); 1706 if (mode == EVP_CIPH_CBC_MODE) { 1707 eivlen = EVP_CIPHER_CTX_iv_length(s->enc_write_ctx); 1708 if (eivlen <= 1) 1709 eivlen = 0; 1710 } 1711 /* Need explicit part of IV for GCM mode */ 1712 else if (mode == EVP_CIPH_GCM_MODE) 1713 eivlen = EVP_GCM_TLS_EXPLICIT_IV_LEN; 1714 else 1715 eivlen = 0; 1716 } else 1717 eivlen = 0; 1718 1719 /* lets setup the record stuff. */ 1720 wr->data = p + eivlen; /* make room for IV in case of CBC */ 1721 wr->length = (int)len; 1722 wr->input = (unsigned char *)buf; 1723 1724 /* 1725 * we now 'read' from wr->input, wr->length bytes into wr->data 1726 */ 1727 1728 /* first we compress */ 1729 if (s->compress != NULL) { 1730 if (!ssl3_do_compress(s)) { 1731 SSLerr(SSL_F_DO_DTLS1_WRITE, SSL_R_COMPRESSION_FAILURE); 1732 goto err; 1733 } 1734 } else { 1735 memcpy(wr->data, wr->input, wr->length); 1736 wr->input = wr->data; 1737 } 1738 1739 /* 1740 * we should still have the output to wr->data and the input from 1741 * wr->input. Length should be wr->length. wr->data still points in the 1742 * wb->buf 1743 */ 1744 1745 if (mac_size != 0) { 1746 if (s->method->ssl3_enc->mac(s, &(p[wr->length + eivlen]), 1) < 0) 1747 goto err; 1748 wr->length += mac_size; 1749 } 1750 1751 /* this is true regardless of mac size */ 1752 wr->input = p; 1753 wr->data = p; 1754 1755 if (eivlen) 1756 wr->length += eivlen; 1757 1758 if (s->method->ssl3_enc->enc(s, 1) < 1) 1759 goto err; 1760 1761 /* record length after mac and block padding */ 1762 /* 1763 * if (type == SSL3_RT_APPLICATION_DATA || (type == SSL3_RT_ALERT && ! 1764 * SSL_in_init(s))) 1765 */ 1766 1767 /* there's only one epoch between handshake and app data */ 1768 1769 s2n(s->d1->w_epoch, pseq); 1770 1771 /* XDTLS: ?? */ 1772 /* 1773 * else s2n(s->d1->handshake_epoch, pseq); 1774 */ 1775 1776 memcpy(pseq, &(s->s3->write_sequence[2]), 6); 1777 pseq += 6; 1778 s2n(wr->length, pseq); 1779 1780 if (s->msg_callback) 1781 s->msg_callback(1, 0, SSL3_RT_HEADER, pseq - DTLS1_RT_HEADER_LENGTH, 1782 DTLS1_RT_HEADER_LENGTH, s, s->msg_callback_arg); 1783 1784 /* 1785 * we should now have wr->data pointing to the encrypted data, which is 1786 * wr->length long 1787 */ 1788 wr->type = type; /* not needed but helps for debugging */ 1789 wr->length += DTLS1_RT_HEADER_LENGTH; 1790 1791#if 0 /* this is now done at the message layer */ 1792 /* buffer the record, making it easy to handle retransmits */ 1793 if (type == SSL3_RT_HANDSHAKE || type == SSL3_RT_CHANGE_CIPHER_SPEC) 1794 dtls1_buffer_record(s, wr->data, wr->length, 1795 *((PQ_64BIT *) & (s->s3->write_sequence[0]))); 1796#endif 1797 1798 ssl3_record_sequence_update(&(s->s3->write_sequence[0])); 1799 1800 if (create_empty_fragment) { 1801 /* 1802 * we are in a recursive call; just return the length, don't write 1803 * out anything here 1804 */ 1805 return wr->length; 1806 } 1807 1808 /* now let's set up wb */ 1809 wb->left = prefix_len + wr->length; 1810 wb->offset = 0; 1811 1812 /* 1813 * memorize arguments so that ssl3_write_pending can detect bad write 1814 * retries later 1815 */ 1816 s->s3->wpend_tot = len; 1817 s->s3->wpend_buf = buf; 1818 s->s3->wpend_type = type; 1819 s->s3->wpend_ret = len; 1820 1821 /* we now just need to write the buffer */ 1822 return ssl3_write_pending(s, type, buf, len); 1823 err: 1824 return -1; 1825} 1826 1827static int dtls1_record_replay_check(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 memcpy(s->s3->rrec.seq_num, seq, 8); 1836 return 1; /* this record in new */ 1837 } 1838 shift = -cmp; 1839 if (shift >= sizeof(bitmap->map) * 8) 1840 return 0; /* stale, outside the window */ 1841 else if (bitmap->map & (1UL << shift)) 1842 return 0; /* record previously received */ 1843 1844 memcpy(s->s3->rrec.seq_num, seq, 8); 1845 return 1; 1846} 1847 1848static void dtls1_record_bitmap_update(SSL *s, DTLS1_BITMAP *bitmap) 1849{ 1850 int cmp; 1851 unsigned int shift; 1852 const unsigned char *seq = s->s3->read_sequence; 1853 1854 cmp = satsub64be(seq, bitmap->max_seq_num); 1855 if (cmp > 0) { 1856 shift = cmp; 1857 if (shift < sizeof(bitmap->map) * 8) 1858 bitmap->map <<= shift, bitmap->map |= 1UL; 1859 else 1860 bitmap->map = 1UL; 1861 memcpy(bitmap->max_seq_num, seq, 8); 1862 } else { 1863 shift = -cmp; 1864 if (shift < sizeof(bitmap->map) * 8) 1865 bitmap->map |= 1UL << shift; 1866 } 1867} 1868 1869int dtls1_dispatch_alert(SSL *s) 1870{ 1871 int i, j; 1872 void (*cb) (const SSL *ssl, int type, int val) = NULL; 1873 unsigned char buf[DTLS1_AL_HEADER_LENGTH]; 1874 unsigned char *ptr = &buf[0]; 1875 1876 s->s3->alert_dispatch = 0; 1877 1878 memset(buf, 0x00, sizeof(buf)); 1879 *ptr++ = s->s3->send_alert[0]; 1880 *ptr++ = s->s3->send_alert[1]; 1881 1882#ifdef DTLS1_AD_MISSING_HANDSHAKE_MESSAGE 1883 if (s->s3->send_alert[1] == DTLS1_AD_MISSING_HANDSHAKE_MESSAGE) { 1884 s2n(s->d1->handshake_read_seq, ptr); 1885# if 0 1886 if (s->d1->r_msg_hdr.frag_off == 0) 1887 /* 1888 * waiting for a new msg 1889 */ 1890 else 1891 s2n(s->d1->r_msg_hdr.seq, ptr); /* partial msg read */ 1892# endif 1893 1894# if 0 1895 fprintf(stderr, 1896 "s->d1->handshake_read_seq = %d, s->d1->r_msg_hdr.seq = %d\n", 1897 s->d1->handshake_read_seq, s->d1->r_msg_hdr.seq); 1898# endif 1899 l2n3(s->d1->r_msg_hdr.frag_off, ptr); 1900 } 1901#endif 1902 1903 i = do_dtls1_write(s, SSL3_RT_ALERT, &buf[0], sizeof(buf), 0); 1904 if (i <= 0) { 1905 s->s3->alert_dispatch = 1; 1906 /* fprintf( stderr, "not done with alert\n" ); */ 1907 } else { 1908 if (s->s3->send_alert[0] == SSL3_AL_FATAL 1909#ifdef DTLS1_AD_MISSING_HANDSHAKE_MESSAGE 1910 || s->s3->send_alert[1] == DTLS1_AD_MISSING_HANDSHAKE_MESSAGE 1911#endif 1912 ) 1913 (void)BIO_flush(s->wbio); 1914 1915 if (s->msg_callback) 1916 s->msg_callback(1, s->version, SSL3_RT_ALERT, s->s3->send_alert, 1917 2, s, s->msg_callback_arg); 1918 1919 if (s->info_callback != NULL) 1920 cb = s->info_callback; 1921 else if (s->ctx->info_callback != NULL) 1922 cb = s->ctx->info_callback; 1923 1924 if (cb != NULL) { 1925 j = (s->s3->send_alert[0] << 8) | s->s3->send_alert[1]; 1926 cb(s, SSL_CB_WRITE_ALERT, j); 1927 } 1928 } 1929 return (i); 1930} 1931 1932static DTLS1_BITMAP *dtls1_get_bitmap(SSL *s, SSL3_RECORD *rr, 1933 unsigned int *is_next_epoch) 1934{ 1935 1936 *is_next_epoch = 0; 1937 1938 /* In current epoch, accept HM, CCS, DATA, & ALERT */ 1939 if (rr->epoch == s->d1->r_epoch) 1940 return &s->d1->bitmap; 1941 1942 /* 1943 * Only HM and ALERT messages can be from the next epoch and only if we 1944 * have already processed all of the unprocessed records from the last 1945 * epoch 1946 */ 1947 else if (rr->epoch == (unsigned long)(s->d1->r_epoch + 1) && 1948 s->d1->unprocessed_rcds.epoch != s->d1->r_epoch && 1949 (rr->type == SSL3_RT_HANDSHAKE || rr->type == SSL3_RT_ALERT)) { 1950 *is_next_epoch = 1; 1951 return &s->d1->next_bitmap; 1952 } 1953 1954 return NULL; 1955} 1956 1957#if 0 1958static int 1959dtls1_record_needs_buffering(SSL *s, SSL3_RECORD *rr, 1960 unsigned short *priority, unsigned long *offset) 1961{ 1962 1963 /* alerts are passed up immediately */ 1964 if (rr->type == SSL3_RT_APPLICATION_DATA || rr->type == SSL3_RT_ALERT) 1965 return 0; 1966 1967 /* 1968 * Only need to buffer if a handshake is underway. (this implies that 1969 * Hello Request and Client Hello are passed up immediately) 1970 */ 1971 if (SSL_in_init(s)) { 1972 unsigned char *data = rr->data; 1973 /* need to extract the HM/CCS sequence number here */ 1974 if (rr->type == SSL3_RT_HANDSHAKE || 1975 rr->type == SSL3_RT_CHANGE_CIPHER_SPEC) { 1976 unsigned short seq_num; 1977 struct hm_header_st msg_hdr; 1978 struct ccs_header_st ccs_hdr; 1979 1980 if (rr->type == SSL3_RT_HANDSHAKE) { 1981 dtls1_get_message_header(data, &msg_hdr); 1982 seq_num = msg_hdr.seq; 1983 *offset = msg_hdr.frag_off; 1984 } else { 1985 dtls1_get_ccs_header(data, &ccs_hdr); 1986 seq_num = ccs_hdr.seq; 1987 *offset = 0; 1988 } 1989 1990 /* 1991 * this is either a record we're waiting for, or a retransmit of 1992 * something we happened to previously receive (higher layers 1993 * will drop the repeat silently 1994 */ 1995 if (seq_num < s->d1->handshake_read_seq) 1996 return 0; 1997 if (rr->type == SSL3_RT_HANDSHAKE && 1998 seq_num == s->d1->handshake_read_seq && 1999 msg_hdr.frag_off < s->d1->r_msg_hdr.frag_off) 2000 return 0; 2001 else if (seq_num == s->d1->handshake_read_seq && 2002 (rr->type == SSL3_RT_CHANGE_CIPHER_SPEC || 2003 msg_hdr.frag_off == s->d1->r_msg_hdr.frag_off)) 2004 return 0; 2005 else { 2006 *priority = seq_num; 2007 return 1; 2008 } 2009 } else /* unknown record type */ 2010 return 0; 2011 } 2012 2013 return 0; 2014} 2015#endif 2016 2017void dtls1_reset_seq_numbers(SSL *s, int rw) 2018{ 2019 unsigned char *seq; 2020 unsigned int seq_bytes = sizeof(s->s3->read_sequence); 2021 2022 if (rw & SSL3_CC_READ) { 2023 seq = s->s3->read_sequence; 2024 s->d1->r_epoch++; 2025 memcpy(&(s->d1->bitmap), &(s->d1->next_bitmap), sizeof(DTLS1_BITMAP)); 2026 memset(&(s->d1->next_bitmap), 0x00, sizeof(DTLS1_BITMAP)); 2027 2028 /* 2029 * We must not use any buffered messages received from the previous 2030 * epoch 2031 */ 2032 dtls1_clear_received_buffer(s); 2033 } else { 2034 seq = s->s3->write_sequence; 2035 memcpy(s->d1->last_write_sequence, seq, 2036 sizeof(s->s3->write_sequence)); 2037 s->d1->w_epoch++; 2038 } 2039 2040 memset(seq, 0x00, seq_bytes); 2041} 2042