1 /* 2 * Copyright 2005-2025 The OpenSSL Project Authors. All Rights Reserved. 3 * 4 * Licensed under the Apache License 2.0 (the "License"). You may not use 5 * this file except in compliance with the License. You can obtain a copy 6 * in the file LICENSE in the source distribution or at 7 * https://www.openssl.org/source/license.html 8 */ 9 10 #include <assert.h> 11 #include <limits.h> 12 #include <string.h> 13 #include <stdio.h> 14 #include "../ssl_local.h" 15 #include "statem_local.h" 16 #include "internal/cryptlib.h" 17 #include "internal/ssl_unwrap.h" 18 #include <openssl/buffer.h> 19 20 #define RSMBLY_BITMASK_SIZE(msg_len) (((msg_len) + 7) / 8) 21 22 #define RSMBLY_BITMASK_MARK(bitmask, start, end) { \ 23 if ((end) - (start) <= 8) { \ 24 long ii; \ 25 for (ii = (start); ii < (end); ii++) bitmask[((ii) >> 3)] |= (1 << ((ii) & 7)); \ 26 } else { \ 27 long ii; \ 28 bitmask[((start) >> 3)] |= bitmask_start_values[((start) & 7)]; \ 29 for (ii = (((start) >> 3) + 1); ii < ((((end) - 1)) >> 3); ii++) bitmask[ii] = 0xff; \ 30 bitmask[(((end) - 1) >> 3)] |= bitmask_end_values[((end) & 7)]; \ 31 } } 32 33 #define RSMBLY_BITMASK_IS_COMPLETE(bitmask, msg_len, is_complete) { \ 34 long ii; \ 35 is_complete = 1; \ 36 if (bitmask[(((msg_len) - 1) >> 3)] != bitmask_end_values[((msg_len) & 7)]) is_complete = 0; \ 37 if (is_complete) for (ii = (((msg_len) - 1) >> 3) - 1; ii >= 0 ; ii--) \ 38 if (bitmask[ii] != 0xff) { is_complete = 0; break; } } 39 40 static const unsigned char bitmask_start_values[] = { 41 0xff, 0xfe, 0xfc, 0xf8, 0xf0, 0xe0, 0xc0, 0x80 42 }; 43 static const unsigned char bitmask_end_values[] = { 44 0xff, 0x01, 0x03, 0x07, 0x0f, 0x1f, 0x3f, 0x7f 45 }; 46 47 static void dtls1_fix_message_header(SSL_CONNECTION *s, size_t frag_off, 48 size_t frag_len); 49 static unsigned char *dtls1_write_message_header(SSL_CONNECTION *s, 50 unsigned char *p); 51 static void dtls1_set_message_header_int(SSL_CONNECTION *s, unsigned char mt, 52 size_t len, 53 unsigned short seq_num, 54 size_t frag_off, 55 size_t frag_len); 56 static int dtls_get_reassembled_message(SSL_CONNECTION *s, int *errtype, 57 size_t *len); 58 59 static hm_fragment *dtls1_hm_fragment_new(size_t frag_len, int reassembly) 60 { 61 hm_fragment *frag = NULL; 62 unsigned char *buf = NULL; 63 unsigned char *bitmask = NULL; 64 65 if ((frag = OPENSSL_zalloc(sizeof(*frag))) == NULL) 66 return NULL; 67 68 if (frag_len) { 69 if ((buf = OPENSSL_malloc(frag_len)) == NULL) { 70 OPENSSL_free(frag); 71 return NULL; 72 } 73 } 74 75 /* zero length fragment gets zero frag->fragment */ 76 frag->fragment = buf; 77 78 /* Initialize reassembly bitmask if necessary */ 79 if (reassembly) { 80 bitmask = OPENSSL_zalloc(RSMBLY_BITMASK_SIZE(frag_len)); 81 if (bitmask == NULL) { 82 OPENSSL_free(buf); 83 OPENSSL_free(frag); 84 return NULL; 85 } 86 } 87 88 frag->reassembly = bitmask; 89 90 return frag; 91 } 92 93 void dtls1_hm_fragment_free(hm_fragment *frag) 94 { 95 if (!frag) 96 return; 97 98 OPENSSL_free(frag->fragment); 99 OPENSSL_free(frag->reassembly); 100 OPENSSL_free(frag); 101 } 102 103 /* 104 * send s->init_buf in records of type 'type' (SSL3_RT_HANDSHAKE or 105 * SSL3_RT_CHANGE_CIPHER_SPEC) 106 */ 107 int dtls1_do_write(SSL_CONNECTION *s, uint8_t type) 108 { 109 int ret; 110 size_t written; 111 size_t curr_mtu; 112 int retry = 1; 113 size_t len, frag_off, overhead, used_len; 114 SSL *ssl = SSL_CONNECTION_GET_SSL(s); 115 SSL *ussl = SSL_CONNECTION_GET_USER_SSL(s); 116 uint8_t saved_payload[DTLS1_HM_HEADER_LENGTH]; 117 118 if (!dtls1_query_mtu(s)) 119 return -1; 120 121 if (s->d1->mtu < dtls1_min_mtu(s)) 122 /* should have something reasonable now */ 123 return -1; 124 125 if (s->init_off == 0 && type == SSL3_RT_HANDSHAKE) { 126 if (!ossl_assert(s->init_num == 127 s->d1->w_msg_hdr.msg_len + DTLS1_HM_HEADER_LENGTH)) 128 return -1; 129 } 130 131 overhead = s->rlayer.wrlmethod->get_max_record_overhead(s->rlayer.wrl); 132 133 frag_off = 0; 134 s->rwstate = SSL_NOTHING; 135 136 /* s->init_num shouldn't ever be < 0...but just in case */ 137 while (s->init_num > 0) { 138 if (type == SSL3_RT_HANDSHAKE && s->init_off != 0) { 139 /* We must be writing a fragment other than the first one */ 140 141 if (frag_off > 0) { 142 /* This is the first attempt at writing out this fragment */ 143 144 if (s->init_off <= DTLS1_HM_HEADER_LENGTH) { 145 /* 146 * Each fragment that was already sent must at least have 147 * contained the message header plus one other byte. 148 * Therefore |init_off| must have progressed by at least 149 * |DTLS1_HM_HEADER_LENGTH + 1| bytes. If not something went 150 * wrong. 151 */ 152 return -1; 153 } 154 155 /* 156 * Adjust |init_off| and |init_num| to allow room for a new 157 * message header for this fragment. 158 */ 159 s->init_off -= DTLS1_HM_HEADER_LENGTH; 160 s->init_num += DTLS1_HM_HEADER_LENGTH; 161 } else { 162 /* 163 * We must have been called again after a retry so use the 164 * fragment offset from our last attempt. We do not need 165 * to adjust |init_off| and |init_num| as above, because 166 * that should already have been done before the retry. 167 */ 168 frag_off = s->d1->w_msg_hdr.frag_off; 169 } 170 } 171 172 used_len = BIO_wpending(s->wbio) + overhead; 173 if (s->d1->mtu > used_len) 174 curr_mtu = s->d1->mtu - used_len; 175 else 176 curr_mtu = 0; 177 178 if (curr_mtu <= DTLS1_HM_HEADER_LENGTH) { 179 /* 180 * grr.. we could get an error if MTU picked was wrong 181 */ 182 ret = BIO_flush(s->wbio); 183 if (ret <= 0) { 184 s->rwstate = SSL_WRITING; 185 return ret; 186 } 187 if (s->d1->mtu > overhead + DTLS1_HM_HEADER_LENGTH) { 188 curr_mtu = s->d1->mtu - overhead; 189 } else { 190 /* Shouldn't happen */ 191 return -1; 192 } 193 } 194 195 /* 196 * We just checked that s->init_num > 0 so this cast should be safe 197 */ 198 if (((unsigned int)s->init_num) > curr_mtu) 199 len = curr_mtu; 200 else 201 len = s->init_num; 202 203 if (len > ssl_get_max_send_fragment(s)) 204 len = ssl_get_max_send_fragment(s); 205 206 /* 207 * XDTLS: this function is too long. split out the CCS part 208 */ 209 if (type == SSL3_RT_HANDSHAKE) { 210 if (len < DTLS1_HM_HEADER_LENGTH) { 211 /* 212 * len is so small that we really can't do anything sensible 213 * so fail 214 */ 215 return -1; 216 } 217 dtls1_fix_message_header(s, frag_off, len - DTLS1_HM_HEADER_LENGTH); 218 219 /* 220 * Save the data that will be overwritten by 221 * dtls1_write_messsage_header so no corruption occurs when using 222 * a msg callback. 223 */ 224 if (s->msg_callback && s->init_off != 0) 225 memcpy(saved_payload, &s->init_buf->data[s->init_off], 226 sizeof(saved_payload)); 227 228 dtls1_write_message_header(s, 229 (unsigned char *)&s->init_buf-> 230 data[s->init_off]); 231 } 232 233 ret = dtls1_write_bytes(s, type, &s->init_buf->data[s->init_off], len, 234 &written); 235 236 if (type == SSL3_RT_HANDSHAKE && s->msg_callback && s->init_off != 0) 237 memcpy(&s->init_buf->data[s->init_off], saved_payload, 238 sizeof(saved_payload)); 239 240 if (ret <= 0) { 241 /* 242 * might need to update MTU here, but we don't know which 243 * previous packet caused the failure -- so can't really 244 * retransmit anything. continue as if everything is fine and 245 * wait for an alert to handle the retransmit 246 */ 247 if (retry && BIO_ctrl(SSL_get_wbio(ssl), 248 BIO_CTRL_DGRAM_MTU_EXCEEDED, 0, NULL) > 0) { 249 if (!(SSL_get_options(ssl) & SSL_OP_NO_QUERY_MTU)) { 250 if (!dtls1_query_mtu(s)) 251 return -1; 252 /* Have one more go */ 253 retry = 0; 254 } else 255 return -1; 256 } else { 257 return -1; 258 } 259 } else { 260 261 /* 262 * bad if this assert fails, only part of the handshake message 263 * got sent. but why would this happen? 264 */ 265 if (!ossl_assert(len == written)) 266 return -1; 267 268 /* 269 * We should not exceed the MTU size. If compression is in use 270 * then the max record overhead calculation is unreliable so we do 271 * not check in that case. We use assert rather than ossl_assert 272 * because in a production build, if this assert were ever to fail, 273 * then the best thing to do is probably carry on regardless. 274 */ 275 assert(s->s3.tmp.new_compression != NULL 276 || BIO_wpending(s->wbio) <= (int)s->d1->mtu); 277 278 if (type == SSL3_RT_HANDSHAKE && !s->d1->retransmitting) { 279 /* 280 * should not be done for 'Hello Request's, but in that case 281 * we'll ignore the result anyway 282 */ 283 unsigned char *p = 284 (unsigned char *)&s->init_buf->data[s->init_off]; 285 const struct hm_header_st *msg_hdr = &s->d1->w_msg_hdr; 286 size_t xlen; 287 288 if (frag_off == 0 && s->version != DTLS1_BAD_VER) { 289 /* 290 * reconstruct message header is if it is being sent in 291 * single fragment 292 */ 293 *p++ = msg_hdr->type; 294 l2n3(msg_hdr->msg_len, p); 295 s2n(msg_hdr->seq, p); 296 l2n3(0, p); 297 l2n3(msg_hdr->msg_len, p); 298 p -= DTLS1_HM_HEADER_LENGTH; 299 xlen = written; 300 } else { 301 p += DTLS1_HM_HEADER_LENGTH; 302 xlen = written - DTLS1_HM_HEADER_LENGTH; 303 } 304 305 if (!ssl3_finish_mac(s, p, xlen)) 306 return -1; 307 } 308 309 if (written == s->init_num) { 310 if (s->msg_callback) 311 s->msg_callback(1, s->version, type, s->init_buf->data, 312 s->init_off + s->init_num, ussl, 313 s->msg_callback_arg); 314 315 s->init_off = 0; /* done writing this message */ 316 s->init_num = 0; 317 318 return 1; 319 } 320 s->init_off += written; 321 s->init_num -= written; 322 written -= DTLS1_HM_HEADER_LENGTH; 323 frag_off += written; 324 325 /* 326 * We save the fragment offset for the next fragment so we have it 327 * available in case of an IO retry. We don't know the length of the 328 * next fragment yet so just set that to 0 for now. It will be 329 * updated again later. 330 */ 331 dtls1_fix_message_header(s, frag_off, 0); 332 } 333 } 334 return 0; 335 } 336 337 int dtls_get_message(SSL_CONNECTION *s, int *mt) 338 { 339 struct hm_header_st *msg_hdr; 340 unsigned char *p; 341 size_t msg_len; 342 size_t tmplen; 343 int errtype; 344 345 msg_hdr = &s->d1->r_msg_hdr; 346 memset(msg_hdr, 0, sizeof(*msg_hdr)); 347 348 again: 349 if (!dtls_get_reassembled_message(s, &errtype, &tmplen)) { 350 if (errtype == DTLS1_HM_BAD_FRAGMENT 351 || errtype == DTLS1_HM_FRAGMENT_RETRY) { 352 /* bad fragment received */ 353 goto again; 354 } 355 return 0; 356 } 357 358 *mt = s->s3.tmp.message_type; 359 360 p = (unsigned char *)s->init_buf->data; 361 362 if (*mt == SSL3_MT_CHANGE_CIPHER_SPEC) { 363 if (s->msg_callback) { 364 s->msg_callback(0, s->version, SSL3_RT_CHANGE_CIPHER_SPEC, 365 p, 1, SSL_CONNECTION_GET_USER_SSL(s), 366 s->msg_callback_arg); 367 } 368 /* 369 * This isn't a real handshake message so skip the processing below. 370 */ 371 return 1; 372 } 373 374 msg_len = msg_hdr->msg_len; 375 376 /* reconstruct message header */ 377 *(p++) = msg_hdr->type; 378 l2n3(msg_len, p); 379 s2n(msg_hdr->seq, p); 380 l2n3(0, p); 381 l2n3(msg_len, p); 382 383 memset(msg_hdr, 0, sizeof(*msg_hdr)); 384 385 s->d1->handshake_read_seq++; 386 387 s->init_msg = s->init_buf->data + DTLS1_HM_HEADER_LENGTH; 388 389 return 1; 390 } 391 392 /* 393 * Actually we already have the message body - but this is an opportunity for 394 * DTLS to do any further processing it wants at the same point that TLS would 395 * be asked for the message body. 396 */ 397 int dtls_get_message_body(SSL_CONNECTION *s, size_t *len) 398 { 399 unsigned char *msg = (unsigned char *)s->init_buf->data; 400 size_t msg_len = s->init_num + DTLS1_HM_HEADER_LENGTH; 401 402 if (s->s3.tmp.message_type == SSL3_MT_CHANGE_CIPHER_SPEC) { 403 /* Nothing to be done */ 404 goto end; 405 } 406 /* 407 * If receiving Finished, record MAC of prior handshake messages for 408 * Finished verification. 409 */ 410 if (*(s->init_buf->data) == SSL3_MT_FINISHED && !ssl3_take_mac(s)) { 411 /* SSLfatal() already called */ 412 return 0; 413 } 414 415 if (s->version == DTLS1_BAD_VER) { 416 msg += DTLS1_HM_HEADER_LENGTH; 417 msg_len -= DTLS1_HM_HEADER_LENGTH; 418 } 419 420 if (!ssl3_finish_mac(s, msg, msg_len)) 421 return 0; 422 423 if (s->msg_callback) 424 s->msg_callback(0, s->version, SSL3_RT_HANDSHAKE, 425 s->init_buf->data, s->init_num + DTLS1_HM_HEADER_LENGTH, 426 SSL_CONNECTION_GET_USER_SSL(s), s->msg_callback_arg); 427 428 end: 429 *len = s->init_num; 430 return 1; 431 } 432 433 /* 434 * dtls1_max_handshake_message_len returns the maximum number of bytes 435 * permitted in a DTLS handshake message for |s|. The minimum is 16KB, but 436 * may be greater if the maximum certificate list size requires it. 437 */ 438 static size_t dtls1_max_handshake_message_len(const SSL_CONNECTION *s) 439 { 440 size_t max_len = DTLS1_HM_HEADER_LENGTH + SSL3_RT_MAX_ENCRYPTED_LENGTH; 441 if (max_len < s->max_cert_list) 442 return s->max_cert_list; 443 return max_len; 444 } 445 446 static int dtls1_preprocess_fragment(SSL_CONNECTION *s, 447 struct hm_header_st *msg_hdr) 448 { 449 size_t frag_off, frag_len, msg_len; 450 451 msg_len = msg_hdr->msg_len; 452 frag_off = msg_hdr->frag_off; 453 frag_len = msg_hdr->frag_len; 454 455 /* sanity checking */ 456 if ((frag_off + frag_len) > msg_len 457 || msg_len > dtls1_max_handshake_message_len(s)) { 458 SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_R_EXCESSIVE_MESSAGE_SIZE); 459 return 0; 460 } 461 462 if (s->d1->r_msg_hdr.frag_off == 0) { /* first fragment */ 463 /* 464 * msg_len is limited to 2^24, but is effectively checked against 465 * dtls_max_handshake_message_len(s) above 466 */ 467 if (!BUF_MEM_grow_clean(s->init_buf, msg_len + DTLS1_HM_HEADER_LENGTH)) { 468 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_BUF_LIB); 469 return 0; 470 } 471 472 s->s3.tmp.message_size = msg_len; 473 s->d1->r_msg_hdr.msg_len = msg_len; 474 s->s3.tmp.message_type = msg_hdr->type; 475 s->d1->r_msg_hdr.type = msg_hdr->type; 476 s->d1->r_msg_hdr.seq = msg_hdr->seq; 477 } else if (msg_len != s->d1->r_msg_hdr.msg_len) { 478 /* 479 * They must be playing with us! BTW, failure to enforce upper limit 480 * would open possibility for buffer overrun. 481 */ 482 SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_R_EXCESSIVE_MESSAGE_SIZE); 483 return 0; 484 } 485 486 return 1; 487 } 488 489 /* 490 * Returns 1 if there is a buffered fragment available, 0 if not, or -1 on a 491 * fatal error. 492 */ 493 static int dtls1_retrieve_buffered_fragment(SSL_CONNECTION *s, size_t *len) 494 { 495 /*- 496 * (0) check whether the desired fragment is available 497 * if so: 498 * (1) copy over the fragment to s->init_buf->data[] 499 * (2) update s->init_num 500 */ 501 pitem *item; 502 piterator iter; 503 hm_fragment *frag; 504 int ret; 505 int chretran = 0; 506 507 iter = pqueue_iterator(s->d1->buffered_messages); 508 do { 509 item = pqueue_next(&iter); 510 if (item == NULL) 511 return 0; 512 513 frag = (hm_fragment *)item->data; 514 515 if (frag->msg_header.seq < s->d1->handshake_read_seq) { 516 pitem *next; 517 hm_fragment *nextfrag; 518 519 if (!s->server 520 || frag->msg_header.seq != 0 521 || s->d1->handshake_read_seq != 1 522 || s->statem.hand_state != DTLS_ST_SW_HELLO_VERIFY_REQUEST) { 523 /* 524 * This is a stale message that has been buffered so clear it. 525 * It is safe to pop this message from the queue even though 526 * we have an active iterator 527 */ 528 pqueue_pop(s->d1->buffered_messages); 529 dtls1_hm_fragment_free(frag); 530 pitem_free(item); 531 item = NULL; 532 frag = NULL; 533 } else { 534 /* 535 * We have fragments for a ClientHello without a cookie, 536 * even though we have sent a HelloVerifyRequest. It is possible 537 * that the HelloVerifyRequest got lost and this is a 538 * retransmission of the original ClientHello 539 */ 540 next = pqueue_next(&iter); 541 if (next != NULL) { 542 nextfrag = (hm_fragment *)next->data; 543 if (nextfrag->msg_header.seq == s->d1->handshake_read_seq) { 544 /* 545 * We have fragments for both a ClientHello without 546 * cookie and one with. Ditch the one without. 547 */ 548 pqueue_pop(s->d1->buffered_messages); 549 dtls1_hm_fragment_free(frag); 550 pitem_free(item); 551 item = next; 552 frag = nextfrag; 553 } else { 554 chretran = 1; 555 } 556 } else { 557 chretran = 1; 558 } 559 } 560 } 561 } while (item == NULL); 562 563 /* Don't return if reassembly still in progress */ 564 if (frag->reassembly != NULL) 565 return 0; 566 567 if (s->d1->handshake_read_seq == frag->msg_header.seq || chretran) { 568 size_t frag_len = frag->msg_header.frag_len; 569 pqueue_pop(s->d1->buffered_messages); 570 571 /* Calls SSLfatal() as required */ 572 ret = dtls1_preprocess_fragment(s, &frag->msg_header); 573 574 if (ret && frag->msg_header.frag_len > 0) { 575 unsigned char *p = 576 (unsigned char *)s->init_buf->data + DTLS1_HM_HEADER_LENGTH; 577 memcpy(&p[frag->msg_header.frag_off], frag->fragment, 578 frag->msg_header.frag_len); 579 } 580 581 dtls1_hm_fragment_free(frag); 582 pitem_free(item); 583 584 if (ret) { 585 if (chretran) { 586 /* 587 * We got a new ClientHello with a message sequence of 0. 588 * Reset the read/write sequences back to the beginning. 589 * We process it like this is the first time we've seen a 590 * ClientHello from the client. 591 */ 592 s->d1->handshake_read_seq = 0; 593 s->d1->next_handshake_write_seq = 0; 594 } 595 *len = frag_len; 596 return 1; 597 } 598 599 /* Fatal error */ 600 s->init_num = 0; 601 return -1; 602 } else { 603 return 0; 604 } 605 } 606 607 static int dtls1_reassemble_fragment(SSL_CONNECTION *s, 608 const struct hm_header_st *msg_hdr) 609 { 610 hm_fragment *frag = NULL; 611 pitem *item = NULL; 612 int i = -1, is_complete; 613 unsigned char seq64be[8]; 614 size_t frag_len = msg_hdr->frag_len; 615 size_t readbytes; 616 SSL *ssl = SSL_CONNECTION_GET_SSL(s); 617 618 if ((msg_hdr->frag_off + frag_len) > msg_hdr->msg_len || 619 msg_hdr->msg_len > dtls1_max_handshake_message_len(s)) 620 goto err; 621 622 if (frag_len == 0) { 623 return DTLS1_HM_FRAGMENT_RETRY; 624 } 625 626 /* Try to find item in queue */ 627 memset(seq64be, 0, sizeof(seq64be)); 628 seq64be[6] = (unsigned char)(msg_hdr->seq >> 8); 629 seq64be[7] = (unsigned char)msg_hdr->seq; 630 item = pqueue_find(s->d1->buffered_messages, seq64be); 631 632 if (item == NULL) { 633 frag = dtls1_hm_fragment_new(msg_hdr->msg_len, 1); 634 if (frag == NULL) 635 goto err; 636 memcpy(&(frag->msg_header), msg_hdr, sizeof(*msg_hdr)); 637 frag->msg_header.frag_len = frag->msg_header.msg_len; 638 frag->msg_header.frag_off = 0; 639 } else { 640 frag = (hm_fragment *)item->data; 641 if (frag->msg_header.msg_len != msg_hdr->msg_len) { 642 item = NULL; 643 frag = NULL; 644 goto err; 645 } 646 } 647 648 /* 649 * If message is already reassembled, this must be a retransmit and can 650 * be dropped. In this case item != NULL and so frag does not need to be 651 * freed. 652 */ 653 if (frag->reassembly == NULL) { 654 unsigned char devnull[256]; 655 656 while (frag_len) { 657 i = ssl->method->ssl_read_bytes(ssl, SSL3_RT_HANDSHAKE, NULL, 658 devnull, 659 frag_len > 660 sizeof(devnull) ? sizeof(devnull) : 661 frag_len, 0, &readbytes); 662 if (i <= 0) 663 goto err; 664 frag_len -= readbytes; 665 } 666 return DTLS1_HM_FRAGMENT_RETRY; 667 } 668 669 /* read the body of the fragment (header has already been read */ 670 i = ssl->method->ssl_read_bytes(ssl, SSL3_RT_HANDSHAKE, NULL, 671 frag->fragment + msg_hdr->frag_off, 672 frag_len, 0, &readbytes); 673 if (i <= 0 || readbytes != frag_len) 674 i = -1; 675 if (i <= 0) 676 goto err; 677 678 RSMBLY_BITMASK_MARK(frag->reassembly, (long)msg_hdr->frag_off, 679 (long)(msg_hdr->frag_off + frag_len)); 680 681 if (!ossl_assert(msg_hdr->msg_len > 0)) 682 goto err; 683 RSMBLY_BITMASK_IS_COMPLETE(frag->reassembly, (long)msg_hdr->msg_len, 684 is_complete); 685 686 if (is_complete) { 687 OPENSSL_free(frag->reassembly); 688 frag->reassembly = NULL; 689 } 690 691 if (item == NULL) { 692 item = pitem_new(seq64be, frag); 693 if (item == NULL) { 694 i = -1; 695 goto err; 696 } 697 698 item = pqueue_insert(s->d1->buffered_messages, item); 699 /* 700 * pqueue_insert fails iff a duplicate item is inserted. However, 701 * |item| cannot be a duplicate. If it were, |pqueue_find|, above, 702 * would have returned it and control would never have reached this 703 * branch. 704 */ 705 if (!ossl_assert(item != NULL)) 706 goto err; 707 } 708 709 return DTLS1_HM_FRAGMENT_RETRY; 710 711 err: 712 if (item == NULL) 713 dtls1_hm_fragment_free(frag); 714 return -1; 715 } 716 717 static int dtls1_process_out_of_seq_message(SSL_CONNECTION *s, 718 const struct hm_header_st *msg_hdr) 719 { 720 int i = -1; 721 hm_fragment *frag = NULL; 722 pitem *item = NULL; 723 unsigned char seq64be[8]; 724 size_t frag_len = msg_hdr->frag_len; 725 size_t readbytes; 726 SSL *ssl = SSL_CONNECTION_GET_SSL(s); 727 728 if ((msg_hdr->frag_off + frag_len) > msg_hdr->msg_len) 729 goto err; 730 731 /* Try to find item in queue, to prevent duplicate entries */ 732 memset(seq64be, 0, sizeof(seq64be)); 733 seq64be[6] = (unsigned char)(msg_hdr->seq >> 8); 734 seq64be[7] = (unsigned char)msg_hdr->seq; 735 item = pqueue_find(s->d1->buffered_messages, seq64be); 736 737 /* 738 * If we already have an entry and this one is a fragment, don't discard 739 * it and rather try to reassemble it. 740 */ 741 if (item != NULL && frag_len != msg_hdr->msg_len) 742 item = NULL; 743 744 /* 745 * Discard the message if sequence number was already there, is too far 746 * in the future, already in the queue or if we received a FINISHED 747 * before the SERVER_HELLO, which then must be a stale retransmit. 748 */ 749 if (msg_hdr->seq <= s->d1->handshake_read_seq || 750 msg_hdr->seq > s->d1->handshake_read_seq + 10 || item != NULL || 751 (s->d1->handshake_read_seq == 0 && msg_hdr->type == SSL3_MT_FINISHED)) { 752 unsigned char devnull[256]; 753 754 while (frag_len) { 755 i = ssl->method->ssl_read_bytes(ssl, SSL3_RT_HANDSHAKE, NULL, 756 devnull, 757 frag_len > 758 sizeof(devnull) ? sizeof(devnull) : 759 frag_len, 0, &readbytes); 760 if (i <= 0) 761 goto err; 762 frag_len -= readbytes; 763 } 764 } else { 765 if (frag_len != msg_hdr->msg_len) { 766 return dtls1_reassemble_fragment(s, msg_hdr); 767 } 768 769 if (frag_len > dtls1_max_handshake_message_len(s)) 770 goto err; 771 772 frag = dtls1_hm_fragment_new(frag_len, 0); 773 if (frag == NULL) 774 goto err; 775 776 memcpy(&(frag->msg_header), msg_hdr, sizeof(*msg_hdr)); 777 778 if (frag_len) { 779 /* 780 * read the body of the fragment (header has already been read 781 */ 782 i = ssl->method->ssl_read_bytes(ssl, SSL3_RT_HANDSHAKE, NULL, 783 frag->fragment, frag_len, 0, 784 &readbytes); 785 if (i<=0 || readbytes != frag_len) 786 i = -1; 787 if (i <= 0) 788 goto err; 789 } 790 791 item = pitem_new(seq64be, frag); 792 if (item == NULL) 793 goto err; 794 795 item = pqueue_insert(s->d1->buffered_messages, item); 796 /* 797 * pqueue_insert fails iff a duplicate item is inserted. However, 798 * |item| cannot be a duplicate. If it were, |pqueue_find|, above, 799 * would have returned it. Then, either |frag_len| != 800 * |msg_hdr->msg_len| in which case |item| is set to NULL and it will 801 * have been processed with |dtls1_reassemble_fragment|, above, or 802 * the record will have been discarded. 803 */ 804 if (!ossl_assert(item != NULL)) 805 goto err; 806 } 807 808 return DTLS1_HM_FRAGMENT_RETRY; 809 810 err: 811 if (item == NULL) 812 dtls1_hm_fragment_free(frag); 813 return 0; 814 } 815 816 static int dtls_get_reassembled_message(SSL_CONNECTION *s, int *errtype, 817 size_t *len) 818 { 819 size_t mlen, frag_off, frag_len; 820 int i, ret; 821 uint8_t recvd_type; 822 struct hm_header_st msg_hdr; 823 size_t readbytes; 824 SSL *ssl = SSL_CONNECTION_GET_SSL(s); 825 SSL *ussl = SSL_CONNECTION_GET_USER_SSL(s); 826 int chretran = 0; 827 unsigned char *p; 828 829 *errtype = 0; 830 831 p = (unsigned char *)s->init_buf->data; 832 833 redo: 834 /* see if we have the required fragment already */ 835 ret = dtls1_retrieve_buffered_fragment(s, &frag_len); 836 if (ret < 0) { 837 /* SSLfatal() already called */ 838 return 0; 839 } 840 if (ret > 0) { 841 s->init_num = frag_len; 842 *len = frag_len; 843 return 1; 844 } 845 846 /* read handshake message header */ 847 i = ssl->method->ssl_read_bytes(ssl, SSL3_RT_HANDSHAKE, &recvd_type, p, 848 DTLS1_HM_HEADER_LENGTH, 0, &readbytes); 849 if (i <= 0) { /* nbio, or an error */ 850 s->rwstate = SSL_READING; 851 *len = 0; 852 return 0; 853 } 854 if (recvd_type == SSL3_RT_CHANGE_CIPHER_SPEC) { 855 if (p[0] != SSL3_MT_CCS) { 856 SSLfatal(s, SSL_AD_UNEXPECTED_MESSAGE, 857 SSL_R_BAD_CHANGE_CIPHER_SPEC); 858 goto f_err; 859 } 860 861 s->init_num = readbytes - 1; 862 s->init_msg = s->init_buf->data + 1; 863 s->s3.tmp.message_type = SSL3_MT_CHANGE_CIPHER_SPEC; 864 s->s3.tmp.message_size = readbytes - 1; 865 *len = readbytes - 1; 866 return 1; 867 } 868 869 /* Handshake fails if message header is incomplete */ 870 if (readbytes != DTLS1_HM_HEADER_LENGTH) { 871 SSLfatal(s, SSL_AD_UNEXPECTED_MESSAGE, SSL_R_UNEXPECTED_MESSAGE); 872 goto f_err; 873 } 874 875 /* parse the message fragment header */ 876 dtls1_get_message_header(p, &msg_hdr); 877 878 mlen = msg_hdr.msg_len; 879 frag_off = msg_hdr.frag_off; 880 frag_len = msg_hdr.frag_len; 881 882 /* 883 * We must have at least frag_len bytes left in the record to be read. 884 * Fragments must not span records. 885 */ 886 if (frag_len > s->rlayer.tlsrecs[s->rlayer.curr_rec].length) { 887 SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_R_BAD_LENGTH); 888 goto f_err; 889 } 890 891 /* 892 * if this is a future (or stale) message it gets buffered 893 * (or dropped)--no further processing at this time 894 * While listening, we accept seq 1 (ClientHello with cookie) 895 * although we're still expecting seq 0 (ClientHello) 896 */ 897 if (msg_hdr.seq != s->d1->handshake_read_seq) { 898 if (!s->server 899 || msg_hdr.seq != 0 900 || s->d1->handshake_read_seq != 1 901 || p[0] != SSL3_MT_CLIENT_HELLO 902 || s->statem.hand_state != DTLS_ST_SW_HELLO_VERIFY_REQUEST) { 903 *errtype = dtls1_process_out_of_seq_message(s, &msg_hdr); 904 return 0; 905 } 906 /* 907 * We received a ClientHello and sent back a HelloVerifyRequest. We 908 * now seem to have received a retransmitted initial ClientHello. That 909 * is allowed (possibly our HelloVerifyRequest got lost). 910 */ 911 chretran = 1; 912 } 913 914 if (frag_len && frag_len < mlen) { 915 *errtype = dtls1_reassemble_fragment(s, &msg_hdr); 916 return 0; 917 } 918 919 if (!s->server 920 && s->d1->r_msg_hdr.frag_off == 0 921 && s->statem.hand_state != TLS_ST_OK 922 && p[0] == SSL3_MT_HELLO_REQUEST) { 923 /* 924 * The server may always send 'Hello Request' messages -- we are 925 * doing a handshake anyway now, so ignore them if their format is 926 * correct. Does not count for 'Finished' MAC. 927 */ 928 if (p[1] == 0 && p[2] == 0 && p[3] == 0) { 929 if (s->msg_callback) 930 s->msg_callback(0, s->version, SSL3_RT_HANDSHAKE, 931 p, DTLS1_HM_HEADER_LENGTH, ussl, 932 s->msg_callback_arg); 933 934 s->init_num = 0; 935 goto redo; 936 } else { /* Incorrectly formatted Hello request */ 937 938 SSLfatal(s, SSL_AD_UNEXPECTED_MESSAGE, SSL_R_UNEXPECTED_MESSAGE); 939 goto f_err; 940 } 941 } 942 943 if (!dtls1_preprocess_fragment(s, &msg_hdr)) { 944 /* SSLfatal() already called */ 945 goto f_err; 946 } 947 948 if (frag_len > 0) { 949 p += DTLS1_HM_HEADER_LENGTH; 950 951 i = ssl->method->ssl_read_bytes(ssl, SSL3_RT_HANDSHAKE, NULL, 952 &p[frag_off], frag_len, 0, &readbytes); 953 954 /* 955 * This shouldn't ever fail due to NBIO because we already checked 956 * that we have enough data in the record 957 */ 958 if (i <= 0) { 959 s->rwstate = SSL_READING; 960 *len = 0; 961 return 0; 962 } 963 } else { 964 readbytes = 0; 965 } 966 967 /* 968 * XDTLS: an incorrectly formatted fragment should cause the handshake 969 * to fail 970 */ 971 if (readbytes != frag_len) { 972 SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_R_BAD_LENGTH); 973 goto f_err; 974 } 975 976 if (chretran) { 977 /* 978 * We got a new ClientHello with a message sequence of 0. 979 * Reset the read/write sequences back to the beginning. 980 * We process it like this is the first time we've seen a ClientHello 981 * from the client. 982 */ 983 s->d1->handshake_read_seq = 0; 984 s->d1->next_handshake_write_seq = 0; 985 } 986 987 /* 988 * Note that s->init_num is *not* used as current offset in 989 * s->init_buf->data, but as a counter summing up fragments' lengths: as 990 * soon as they sum up to handshake packet length, we assume we have got 991 * all the fragments. 992 */ 993 *len = s->init_num = frag_len; 994 return 1; 995 996 f_err: 997 s->init_num = 0; 998 *len = 0; 999 return 0; 1000 } 1001 1002 /*- 1003 * for these 2 messages, we need to 1004 * ssl->session->read_sym_enc assign 1005 * ssl->session->read_compression assign 1006 * ssl->session->read_hash assign 1007 */ 1008 CON_FUNC_RETURN dtls_construct_change_cipher_spec(SSL_CONNECTION *s, 1009 WPACKET *pkt) 1010 { 1011 if (s->version == DTLS1_BAD_VER) { 1012 s->d1->next_handshake_write_seq++; 1013 1014 if (!WPACKET_put_bytes_u16(pkt, s->d1->handshake_write_seq)) { 1015 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR); 1016 return CON_FUNC_ERROR; 1017 } 1018 } 1019 1020 return CON_FUNC_SUCCESS; 1021 } 1022 1023 #ifndef OPENSSL_NO_SCTP 1024 /* 1025 * Wait for a dry event. Should only be called at a point in the handshake 1026 * where we are not expecting any data from the peer except an alert. 1027 */ 1028 WORK_STATE dtls_wait_for_dry(SSL_CONNECTION *s) 1029 { 1030 int ret, errtype; 1031 size_t len; 1032 SSL *ssl = SSL_CONNECTION_GET_SSL(s); 1033 1034 /* read app data until dry event */ 1035 ret = BIO_dgram_sctp_wait_for_dry(SSL_get_wbio(ssl)); 1036 if (ret < 0) { 1037 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR); 1038 return WORK_ERROR; 1039 } 1040 1041 if (ret == 0) { 1042 /* 1043 * We're not expecting any more messages from the peer at this point - 1044 * but we could get an alert. If an alert is waiting then we will never 1045 * return successfully. Therefore we attempt to read a message. This 1046 * should never succeed but will process any waiting alerts. 1047 */ 1048 if (dtls_get_reassembled_message(s, &errtype, &len)) { 1049 /* The call succeeded! This should never happen */ 1050 SSLfatal(s, SSL_AD_UNEXPECTED_MESSAGE, SSL_R_UNEXPECTED_MESSAGE); 1051 return WORK_ERROR; 1052 } 1053 1054 s->s3.in_read_app_data = 2; 1055 s->rwstate = SSL_READING; 1056 BIO_clear_retry_flags(SSL_get_rbio(ssl)); 1057 BIO_set_retry_read(SSL_get_rbio(ssl)); 1058 return WORK_MORE_A; 1059 } 1060 return WORK_FINISHED_CONTINUE; 1061 } 1062 #endif 1063 1064 int dtls1_read_failed(SSL_CONNECTION *s, int code) 1065 { 1066 SSL *ssl = SSL_CONNECTION_GET_SSL(s); 1067 1068 if (code > 0) { 1069 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR); 1070 return 0; 1071 } 1072 1073 if (!dtls1_is_timer_expired(s) || ossl_statem_in_error(s)) { 1074 /* 1075 * not a timeout, none of our business, let higher layers handle 1076 * this. in fact it's probably an error 1077 */ 1078 return code; 1079 } 1080 /* done, no need to send a retransmit */ 1081 if (!SSL_in_init(ssl)) { 1082 BIO_set_flags(SSL_get_rbio(ssl), BIO_FLAGS_READ); 1083 return code; 1084 } 1085 1086 return dtls1_handle_timeout(s); 1087 } 1088 1089 int dtls1_get_queue_priority(unsigned short seq, int is_ccs) 1090 { 1091 /* 1092 * The index of the retransmission queue actually is the message sequence 1093 * number, since the queue only contains messages of a single handshake. 1094 * However, the ChangeCipherSpec has no message sequence number and so 1095 * using only the sequence will result in the CCS and Finished having the 1096 * same index. To prevent this, the sequence number is multiplied by 2. 1097 * In case of a CCS 1 is subtracted. This does not only differ CSS and 1098 * Finished, it also maintains the order of the index (important for 1099 * priority queues) and fits in the unsigned short variable. 1100 */ 1101 return seq * 2 - is_ccs; 1102 } 1103 1104 int dtls1_retransmit_buffered_messages(SSL_CONNECTION *s) 1105 { 1106 pqueue *sent = s->d1->sent_messages; 1107 piterator iter; 1108 pitem *item; 1109 hm_fragment *frag; 1110 int found = 0; 1111 1112 iter = pqueue_iterator(sent); 1113 1114 for (item = pqueue_next(&iter); item != NULL; item = pqueue_next(&iter)) { 1115 frag = (hm_fragment *)item->data; 1116 if (dtls1_retransmit_message(s, (unsigned short) 1117 dtls1_get_queue_priority 1118 (frag->msg_header.seq, 1119 frag->msg_header.is_ccs), &found) <= 0) 1120 return -1; 1121 } 1122 1123 return 1; 1124 } 1125 1126 int dtls1_buffer_message(SSL_CONNECTION *s, int is_ccs) 1127 { 1128 pitem *item; 1129 hm_fragment *frag; 1130 unsigned char seq64be[8]; 1131 1132 /* 1133 * this function is called immediately after a message has been 1134 * serialized 1135 */ 1136 if (!ossl_assert(s->init_off == 0)) 1137 return 0; 1138 1139 frag = dtls1_hm_fragment_new(s->init_num, 0); 1140 if (frag == NULL) 1141 return 0; 1142 1143 memcpy(frag->fragment, s->init_buf->data, s->init_num); 1144 1145 if (is_ccs) { 1146 /* For DTLS1_BAD_VER the header length is non-standard */ 1147 if (!ossl_assert(s->d1->w_msg_hdr.msg_len + 1148 ((s->version == 1149 DTLS1_BAD_VER) ? 3 : DTLS1_CCS_HEADER_LENGTH) 1150 == (unsigned int)s->init_num)) { 1151 dtls1_hm_fragment_free(frag); 1152 return 0; 1153 } 1154 } else { 1155 if (!ossl_assert(s->d1->w_msg_hdr.msg_len + 1156 DTLS1_HM_HEADER_LENGTH == (unsigned int)s->init_num)) { 1157 dtls1_hm_fragment_free(frag); 1158 return 0; 1159 } 1160 } 1161 1162 frag->msg_header.msg_len = s->d1->w_msg_hdr.msg_len; 1163 frag->msg_header.seq = s->d1->w_msg_hdr.seq; 1164 frag->msg_header.type = s->d1->w_msg_hdr.type; 1165 frag->msg_header.frag_off = 0; 1166 frag->msg_header.frag_len = s->d1->w_msg_hdr.msg_len; 1167 frag->msg_header.is_ccs = is_ccs; 1168 1169 /* save current state */ 1170 frag->msg_header.saved_retransmit_state.wrlmethod = s->rlayer.wrlmethod; 1171 frag->msg_header.saved_retransmit_state.wrl = s->rlayer.wrl; 1172 1173 1174 memset(seq64be, 0, sizeof(seq64be)); 1175 seq64be[6] = 1176 (unsigned 1177 char)(dtls1_get_queue_priority(frag->msg_header.seq, 1178 frag->msg_header.is_ccs) >> 8); 1179 seq64be[7] = 1180 (unsigned 1181 char)(dtls1_get_queue_priority(frag->msg_header.seq, 1182 frag->msg_header.is_ccs)); 1183 1184 item = pitem_new(seq64be, frag); 1185 if (item == NULL) { 1186 dtls1_hm_fragment_free(frag); 1187 return 0; 1188 } 1189 1190 pqueue_insert(s->d1->sent_messages, item); 1191 return 1; 1192 } 1193 1194 int dtls1_retransmit_message(SSL_CONNECTION *s, unsigned short seq, int *found) 1195 { 1196 int ret; 1197 /* XDTLS: for now assuming that read/writes are blocking */ 1198 pitem *item; 1199 hm_fragment *frag; 1200 unsigned long header_length; 1201 unsigned char seq64be[8]; 1202 struct dtls1_retransmit_state saved_state; 1203 1204 /* XDTLS: the requested message ought to be found, otherwise error */ 1205 memset(seq64be, 0, sizeof(seq64be)); 1206 seq64be[6] = (unsigned char)(seq >> 8); 1207 seq64be[7] = (unsigned char)seq; 1208 1209 item = pqueue_find(s->d1->sent_messages, seq64be); 1210 if (item == NULL) { 1211 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR); 1212 *found = 0; 1213 return 0; 1214 } 1215 1216 *found = 1; 1217 frag = (hm_fragment *)item->data; 1218 1219 if (frag->msg_header.is_ccs) 1220 header_length = DTLS1_CCS_HEADER_LENGTH; 1221 else 1222 header_length = DTLS1_HM_HEADER_LENGTH; 1223 1224 memcpy(s->init_buf->data, frag->fragment, 1225 frag->msg_header.msg_len + header_length); 1226 s->init_num = frag->msg_header.msg_len + header_length; 1227 1228 dtls1_set_message_header_int(s, frag->msg_header.type, 1229 frag->msg_header.msg_len, 1230 frag->msg_header.seq, 0, 1231 frag->msg_header.frag_len); 1232 1233 /* save current state */ 1234 saved_state.wrlmethod = s->rlayer.wrlmethod; 1235 saved_state.wrl = s->rlayer.wrl; 1236 1237 s->d1->retransmitting = 1; 1238 1239 /* restore state in which the message was originally sent */ 1240 s->rlayer.wrlmethod = frag->msg_header.saved_retransmit_state.wrlmethod; 1241 s->rlayer.wrl = frag->msg_header.saved_retransmit_state.wrl; 1242 1243 /* 1244 * The old wrl may be still pointing at an old BIO. Update it to what we're 1245 * using now. 1246 */ 1247 s->rlayer.wrlmethod->set1_bio(s->rlayer.wrl, s->wbio); 1248 1249 ret = dtls1_do_write(s, frag->msg_header.is_ccs ? 1250 SSL3_RT_CHANGE_CIPHER_SPEC : SSL3_RT_HANDSHAKE); 1251 1252 /* restore current state */ 1253 s->rlayer.wrlmethod = saved_state.wrlmethod; 1254 s->rlayer.wrl = saved_state.wrl; 1255 1256 s->d1->retransmitting = 0; 1257 1258 (void)BIO_flush(s->wbio); 1259 return ret; 1260 } 1261 1262 void dtls1_set_message_header(SSL_CONNECTION *s, 1263 unsigned char mt, size_t len, 1264 size_t frag_off, size_t frag_len) 1265 { 1266 if (frag_off == 0) { 1267 s->d1->handshake_write_seq = s->d1->next_handshake_write_seq; 1268 s->d1->next_handshake_write_seq++; 1269 } 1270 1271 dtls1_set_message_header_int(s, mt, len, s->d1->handshake_write_seq, 1272 frag_off, frag_len); 1273 } 1274 1275 /* don't actually do the writing, wait till the MTU has been retrieved */ 1276 static void 1277 dtls1_set_message_header_int(SSL_CONNECTION *s, unsigned char mt, 1278 size_t len, unsigned short seq_num, 1279 size_t frag_off, size_t frag_len) 1280 { 1281 struct hm_header_st *msg_hdr = &s->d1->w_msg_hdr; 1282 1283 msg_hdr->type = mt; 1284 msg_hdr->msg_len = len; 1285 msg_hdr->seq = seq_num; 1286 msg_hdr->frag_off = frag_off; 1287 msg_hdr->frag_len = frag_len; 1288 } 1289 1290 static void 1291 dtls1_fix_message_header(SSL_CONNECTION *s, size_t frag_off, size_t frag_len) 1292 { 1293 struct hm_header_st *msg_hdr = &s->d1->w_msg_hdr; 1294 1295 msg_hdr->frag_off = frag_off; 1296 msg_hdr->frag_len = frag_len; 1297 } 1298 1299 static unsigned char *dtls1_write_message_header(SSL_CONNECTION *s, 1300 unsigned char *p) 1301 { 1302 struct hm_header_st *msg_hdr = &s->d1->w_msg_hdr; 1303 1304 *p++ = msg_hdr->type; 1305 l2n3(msg_hdr->msg_len, p); 1306 1307 s2n(msg_hdr->seq, p); 1308 l2n3(msg_hdr->frag_off, p); 1309 l2n3(msg_hdr->frag_len, p); 1310 1311 return p; 1312 } 1313 1314 void dtls1_get_message_header(const unsigned char *data, struct 1315 hm_header_st *msg_hdr) 1316 { 1317 memset(msg_hdr, 0, sizeof(*msg_hdr)); 1318 msg_hdr->type = *(data++); 1319 n2l3(data, msg_hdr->msg_len); 1320 1321 n2s(data, msg_hdr->seq); 1322 n2l3(data, msg_hdr->frag_off); 1323 n2l3(data, msg_hdr->frag_len); 1324 } 1325 1326 int dtls1_set_handshake_header(SSL_CONNECTION *s, WPACKET *pkt, int htype) 1327 { 1328 unsigned char *header; 1329 1330 if (htype == SSL3_MT_CHANGE_CIPHER_SPEC) { 1331 s->d1->handshake_write_seq = s->d1->next_handshake_write_seq; 1332 dtls1_set_message_header_int(s, SSL3_MT_CCS, 0, 1333 s->d1->handshake_write_seq, 0, 0); 1334 if (!WPACKET_put_bytes_u8(pkt, SSL3_MT_CCS)) 1335 return 0; 1336 } else { 1337 dtls1_set_message_header(s, htype, 0, 0, 0); 1338 /* 1339 * We allocate space at the start for the message header. This gets 1340 * filled in later 1341 */ 1342 if (!WPACKET_allocate_bytes(pkt, DTLS1_HM_HEADER_LENGTH, &header) 1343 || !WPACKET_start_sub_packet(pkt)) 1344 return 0; 1345 } 1346 1347 return 1; 1348 } 1349 1350 int dtls1_close_construct_packet(SSL_CONNECTION *s, WPACKET *pkt, int htype) 1351 { 1352 size_t msglen; 1353 1354 if ((htype != SSL3_MT_CHANGE_CIPHER_SPEC && !WPACKET_close(pkt)) 1355 || !WPACKET_get_length(pkt, &msglen) 1356 || msglen > INT_MAX) 1357 return 0; 1358 1359 if (htype != SSL3_MT_CHANGE_CIPHER_SPEC) { 1360 s->d1->w_msg_hdr.msg_len = msglen - DTLS1_HM_HEADER_LENGTH; 1361 s->d1->w_msg_hdr.frag_len = msglen - DTLS1_HM_HEADER_LENGTH; 1362 } 1363 s->init_num = (int)msglen; 1364 s->init_off = 0; 1365 1366 if (htype != DTLS1_MT_HELLO_VERIFY_REQUEST) { 1367 /* Buffer the message to handle re-xmits */ 1368 if (!dtls1_buffer_message(s, htype == SSL3_MT_CHANGE_CIPHER_SPEC 1369 ? 1 : 0)) 1370 return 0; 1371 } 1372 1373 return 1; 1374 } 1375