1 /* $OpenBSD: d1_both.c,v 1.60 2020/09/26 14:43:17 jsing Exp $ */ 2 /* 3 * DTLS implementation written by Nagendra Modadugu 4 * (nagendra@cs.stanford.edu) for the OpenSSL project 2005. 5 */ 6 /* ==================================================================== 7 * Copyright (c) 1998-2005 The OpenSSL Project. All rights reserved. 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that the following conditions 11 * are met: 12 * 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 16 * 2. Redistributions in binary form must reproduce the above copyright 17 * notice, this list of conditions and the following disclaimer in 18 * the documentation and/or other materials provided with the 19 * distribution. 20 * 21 * 3. All advertising materials mentioning features or use of this 22 * software must display the following acknowledgment: 23 * "This product includes software developed by the OpenSSL Project 24 * for use in the OpenSSL Toolkit. (http://www.openssl.org/)" 25 * 26 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to 27 * endorse or promote products derived from this software without 28 * prior written permission. For written permission, please contact 29 * openssl-core@openssl.org. 30 * 31 * 5. Products derived from this software may not be called "OpenSSL" 32 * nor may "OpenSSL" appear in their names without prior written 33 * permission of the OpenSSL Project. 34 * 35 * 6. Redistributions of any form whatsoever must retain the following 36 * acknowledgment: 37 * "This product includes software developed by the OpenSSL Project 38 * for use in the OpenSSL Toolkit (http://www.openssl.org/)" 39 * 40 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY 41 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 42 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 43 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR 44 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 45 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 46 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 47 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 48 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, 49 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 50 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED 51 * OF THE POSSIBILITY OF SUCH DAMAGE. 52 * ==================================================================== 53 * 54 * This product includes cryptographic software written by Eric Young 55 * (eay@cryptsoft.com). This product includes software written by Tim 56 * Hudson (tjh@cryptsoft.com). 57 * 58 */ 59 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com) 60 * All rights reserved. 61 * 62 * This package is an SSL implementation written 63 * by Eric Young (eay@cryptsoft.com). 64 * The implementation was written so as to conform with Netscapes SSL. 65 * 66 * This library is free for commercial and non-commercial use as long as 67 * the following conditions are aheared to. The following conditions 68 * apply to all code found in this distribution, be it the RC4, RSA, 69 * lhash, DES, etc., code; not just the SSL code. The SSL documentation 70 * included with this distribution is covered by the same copyright terms 71 * except that the holder is Tim Hudson (tjh@cryptsoft.com). 72 * 73 * Copyright remains Eric Young's, and as such any Copyright notices in 74 * the code are not to be removed. 75 * If this package is used in a product, Eric Young should be given attribution 76 * as the author of the parts of the library used. 77 * This can be in the form of a textual message at program startup or 78 * in documentation (online or textual) provided with the package. 79 * 80 * Redistribution and use in source and binary forms, with or without 81 * modification, are permitted provided that the following conditions 82 * are met: 83 * 1. Redistributions of source code must retain the copyright 84 * notice, this list of conditions and the following disclaimer. 85 * 2. Redistributions in binary form must reproduce the above copyright 86 * notice, this list of conditions and the following disclaimer in the 87 * documentation and/or other materials provided with the distribution. 88 * 3. All advertising materials mentioning features or use of this software 89 * must display the following acknowledgement: 90 * "This product includes cryptographic software written by 91 * Eric Young (eay@cryptsoft.com)" 92 * The word 'cryptographic' can be left out if the rouines from the library 93 * being used are not cryptographic related :-). 94 * 4. If you include any Windows specific code (or a derivative thereof) from 95 * the apps directory (application code) you must include an acknowledgement: 96 * "This product includes software written by Tim Hudson (tjh@cryptsoft.com)" 97 * 98 * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND 99 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 100 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 101 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 102 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 103 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 104 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 105 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 106 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 107 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 108 * SUCH DAMAGE. 109 * 110 * The licence and distribution terms for any publically available version or 111 * derivative of this code cannot be changed. i.e. this code cannot simply be 112 * copied and put under another distribution licence 113 * [including the GNU Public Licence.] 114 */ 115 116 #include <limits.h> 117 #include <stdio.h> 118 #include <string.h> 119 120 #include "ssl_locl.h" 121 122 #include <openssl/buffer.h> 123 #include <openssl/evp.h> 124 #include <openssl/objects.h> 125 #include <openssl/x509.h> 126 127 #include "pqueue.h" 128 #include "bytestring.h" 129 130 #define RSMBLY_BITMASK_SIZE(msg_len) (((msg_len) + 7) / 8) 131 132 #define RSMBLY_BITMASK_MARK(bitmask, start, end) { \ 133 if ((end) - (start) <= 8) { \ 134 long ii; \ 135 for (ii = (start); ii < (end); ii++) bitmask[((ii) >> 3)] |= (1 << ((ii) & 7)); \ 136 } else { \ 137 long ii; \ 138 bitmask[((start) >> 3)] |= bitmask_start_values[((start) & 7)]; \ 139 for (ii = (((start) >> 3) + 1); ii < ((((end) - 1)) >> 3); ii++) bitmask[ii] = 0xff; \ 140 bitmask[(((end) - 1) >> 3)] |= bitmask_end_values[((end) & 7)]; \ 141 } } 142 143 #define RSMBLY_BITMASK_IS_COMPLETE(bitmask, msg_len, is_complete) { \ 144 long ii; \ 145 OPENSSL_assert((msg_len) > 0); \ 146 is_complete = 1; \ 147 if (bitmask[(((msg_len) - 1) >> 3)] != bitmask_end_values[((msg_len) & 7)]) is_complete = 0; \ 148 if (is_complete) for (ii = (((msg_len) - 1) >> 3) - 1; ii >= 0 ; ii--) \ 149 if (bitmask[ii] != 0xff) { is_complete = 0; break; } } 150 151 static unsigned char bitmask_start_values[] = { 152 0xff, 0xfe, 0xfc, 0xf8, 0xf0, 0xe0, 0xc0, 0x80 153 }; 154 static unsigned char bitmask_end_values[] = { 155 0xff, 0x01, 0x03, 0x07, 0x0f, 0x1f, 0x3f, 0x7f 156 }; 157 158 /* XDTLS: figure out the right values */ 159 static unsigned int g_probable_mtu[] = {1500 - 28, 512 - 28, 256 - 28}; 160 161 static unsigned int dtls1_guess_mtu(unsigned int curr_mtu); 162 static void dtls1_fix_message_header(SSL *s, unsigned long frag_off, 163 unsigned long frag_len); 164 static int dtls1_write_message_header(const struct hm_header_st *msg_hdr, 165 unsigned long frag_off, unsigned long frag_len, unsigned char *p); 166 static long dtls1_get_message_fragment(SSL *s, int st1, int stn, long max, 167 int *ok); 168 169 void dtls1_hm_fragment_free(hm_fragment *frag); 170 171 static hm_fragment * 172 dtls1_hm_fragment_new(unsigned long frag_len, int reassembly) 173 { 174 hm_fragment *frag; 175 176 if ((frag = calloc(1, sizeof(*frag))) == NULL) 177 goto err; 178 179 if (frag_len > 0) { 180 if ((frag->fragment = calloc(1, frag_len)) == NULL) 181 goto err; 182 } 183 184 /* Initialize reassembly bitmask if necessary. */ 185 if (reassembly) { 186 if ((frag->reassembly = calloc(1, 187 RSMBLY_BITMASK_SIZE(frag_len))) == NULL) 188 goto err; 189 } 190 191 return frag; 192 193 err: 194 dtls1_hm_fragment_free(frag); 195 return NULL; 196 } 197 198 void 199 dtls1_hm_fragment_free(hm_fragment *frag) 200 { 201 if (frag == NULL) 202 return; 203 204 if (frag->msg_header.is_ccs) { 205 EVP_CIPHER_CTX_free( 206 frag->msg_header.saved_retransmit_state.enc_write_ctx); 207 EVP_MD_CTX_free( 208 frag->msg_header.saved_retransmit_state.write_hash); 209 } 210 free(frag->fragment); 211 free(frag->reassembly); 212 free(frag); 213 } 214 215 /* send s->internal->init_buf in records of type 'type' (SSL3_RT_HANDSHAKE or SSL3_RT_CHANGE_CIPHER_SPEC) */ 216 int 217 dtls1_do_write(SSL *s, int type) 218 { 219 int ret; 220 int curr_mtu; 221 unsigned int len, frag_off, mac_size, blocksize; 222 223 /* AHA! Figure out the MTU, and stick to the right size */ 224 if (D1I(s)->mtu < dtls1_min_mtu() && 225 !(SSL_get_options(s) & SSL_OP_NO_QUERY_MTU)) { 226 D1I(s)->mtu = BIO_ctrl(SSL_get_wbio(s), 227 BIO_CTRL_DGRAM_QUERY_MTU, 0, NULL); 228 229 /* 230 * I've seen the kernel return bogus numbers when it 231 * doesn't know the MTU (ie., the initial write), so just 232 * make sure we have a reasonable number 233 */ 234 if (D1I(s)->mtu < dtls1_min_mtu()) { 235 D1I(s)->mtu = 0; 236 D1I(s)->mtu = dtls1_guess_mtu(D1I(s)->mtu); 237 BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SET_MTU, 238 D1I(s)->mtu, NULL); 239 } 240 } 241 242 OPENSSL_assert(D1I(s)->mtu >= dtls1_min_mtu()); 243 /* should have something reasonable now */ 244 245 if (s->internal->init_off == 0 && type == SSL3_RT_HANDSHAKE) 246 OPENSSL_assert(s->internal->init_num == 247 (int)D1I(s)->w_msg_hdr.msg_len + DTLS1_HM_HEADER_LENGTH); 248 249 if (s->internal->write_hash) 250 mac_size = EVP_MD_CTX_size(s->internal->write_hash); 251 else 252 mac_size = 0; 253 254 if (s->internal->enc_write_ctx && 255 (EVP_CIPHER_mode( s->internal->enc_write_ctx->cipher) & EVP_CIPH_CBC_MODE)) 256 blocksize = 2 * EVP_CIPHER_block_size(s->internal->enc_write_ctx->cipher); 257 else 258 blocksize = 0; 259 260 frag_off = 0; 261 while (s->internal->init_num) { 262 curr_mtu = D1I(s)->mtu - BIO_wpending(SSL_get_wbio(s)) - 263 DTLS1_RT_HEADER_LENGTH - mac_size - blocksize; 264 265 if (curr_mtu <= DTLS1_HM_HEADER_LENGTH) { 266 /* grr.. we could get an error if MTU picked was wrong */ 267 ret = BIO_flush(SSL_get_wbio(s)); 268 if (ret <= 0) 269 return ret; 270 curr_mtu = D1I(s)->mtu - DTLS1_RT_HEADER_LENGTH - 271 mac_size - blocksize; 272 } 273 274 if (s->internal->init_num > curr_mtu) 275 len = curr_mtu; 276 else 277 len = s->internal->init_num; 278 279 280 /* XDTLS: this function is too long. split out the CCS part */ 281 if (type == SSL3_RT_HANDSHAKE) { 282 if (s->internal->init_off != 0) { 283 OPENSSL_assert(s->internal->init_off > DTLS1_HM_HEADER_LENGTH); 284 s->internal->init_off -= DTLS1_HM_HEADER_LENGTH; 285 s->internal->init_num += DTLS1_HM_HEADER_LENGTH; 286 287 if (s->internal->init_num > curr_mtu) 288 len = curr_mtu; 289 else 290 len = s->internal->init_num; 291 } 292 293 dtls1_fix_message_header(s, frag_off, 294 len - DTLS1_HM_HEADER_LENGTH); 295 296 if (!dtls1_write_message_header(&D1I(s)->w_msg_hdr, 297 D1I(s)->w_msg_hdr.frag_off, D1I(s)->w_msg_hdr.frag_len, 298 (unsigned char *)&s->internal->init_buf->data[s->internal->init_off])) 299 return -1; 300 301 OPENSSL_assert(len >= DTLS1_HM_HEADER_LENGTH); 302 } 303 304 ret = dtls1_write_bytes(s, type, 305 &s->internal->init_buf->data[s->internal->init_off], len); 306 if (ret < 0) { 307 /* 308 * Might need to update MTU here, but we don't know 309 * which previous packet caused the failure -- so 310 * can't really retransmit anything. continue as 311 * if everything is fine and wait for an alert to 312 * handle the retransmit 313 */ 314 if (BIO_ctrl(SSL_get_wbio(s), 315 BIO_CTRL_DGRAM_MTU_EXCEEDED, 0, NULL) > 0) 316 D1I(s)->mtu = BIO_ctrl(SSL_get_wbio(s), 317 BIO_CTRL_DGRAM_QUERY_MTU, 0, NULL); 318 else 319 return (-1); 320 } else { 321 322 /* 323 * Bad if this assert fails, only part of the 324 * handshake message got sent. but why would 325 * this happen? 326 */ 327 OPENSSL_assert(len == (unsigned int)ret); 328 329 if (type == SSL3_RT_HANDSHAKE && 330 !D1I(s)->retransmitting) { 331 /* 332 * Should not be done for 'Hello Request's, 333 * but in that case we'll ignore the result 334 * anyway 335 */ 336 unsigned char *p = (unsigned char *)&s->internal->init_buf->data[s->internal->init_off]; 337 const struct hm_header_st *msg_hdr = &D1I(s)->w_msg_hdr; 338 int xlen; 339 340 if (frag_off == 0) { 341 /* 342 * Reconstruct message header is if it 343 * is being sent in single fragment 344 */ 345 if (!dtls1_write_message_header(msg_hdr, 346 0, msg_hdr->msg_len, p)) 347 return (-1); 348 xlen = ret; 349 } else { 350 p += DTLS1_HM_HEADER_LENGTH; 351 xlen = ret - DTLS1_HM_HEADER_LENGTH; 352 } 353 354 tls1_transcript_record(s, p, xlen); 355 } 356 357 if (ret == s->internal->init_num) { 358 if (s->internal->msg_callback) 359 s->internal->msg_callback(1, s->version, type, 360 s->internal->init_buf->data, 361 (size_t)(s->internal->init_off + s->internal->init_num), 362 s, s->internal->msg_callback_arg); 363 364 s->internal->init_off = 0; 365 /* done writing this message */ 366 s->internal->init_num = 0; 367 368 return (1); 369 } 370 s->internal->init_off += ret; 371 s->internal->init_num -= ret; 372 frag_off += (ret -= DTLS1_HM_HEADER_LENGTH); 373 } 374 } 375 return (0); 376 } 377 378 379 /* 380 * Obtain handshake message of message type 'mt' (any if mt == -1), 381 * maximum acceptable body length 'max'. 382 * Read an entire handshake message. Handshake messages arrive in 383 * fragments. 384 */ 385 long 386 dtls1_get_message(SSL *s, int st1, int stn, int mt, long max, int *ok) 387 { 388 int i, al; 389 struct hm_header_st *msg_hdr; 390 unsigned char *p; 391 unsigned long msg_len; 392 393 /* 394 * s3->internal->tmp is used to store messages that are unexpected, caused 395 * by the absence of an optional handshake message 396 */ 397 if (S3I(s)->tmp.reuse_message) { 398 S3I(s)->tmp.reuse_message = 0; 399 if ((mt >= 0) && (S3I(s)->tmp.message_type != mt)) { 400 al = SSL_AD_UNEXPECTED_MESSAGE; 401 SSLerror(s, SSL_R_UNEXPECTED_MESSAGE); 402 goto f_err; 403 } 404 *ok = 1; 405 s->internal->init_msg = s->internal->init_buf->data + DTLS1_HM_HEADER_LENGTH; 406 s->internal->init_num = (int)S3I(s)->tmp.message_size; 407 return s->internal->init_num; 408 } 409 410 msg_hdr = &D1I(s)->r_msg_hdr; 411 memset(msg_hdr, 0, sizeof(struct hm_header_st)); 412 413 again: 414 i = dtls1_get_message_fragment(s, st1, stn, max, ok); 415 if (i == DTLS1_HM_BAD_FRAGMENT || 416 i == DTLS1_HM_FRAGMENT_RETRY) /* bad fragment received */ 417 goto again; 418 else if (i <= 0 && !*ok) 419 return i; 420 421 p = (unsigned char *)s->internal->init_buf->data; 422 msg_len = msg_hdr->msg_len; 423 424 /* reconstruct message header */ 425 if (!dtls1_write_message_header(msg_hdr, 0, msg_len, p)) 426 return -1; 427 428 msg_len += DTLS1_HM_HEADER_LENGTH; 429 430 tls1_transcript_record(s, p, msg_len); 431 if (s->internal->msg_callback) 432 s->internal->msg_callback(0, s->version, SSL3_RT_HANDSHAKE, p, msg_len, 433 s, s->internal->msg_callback_arg); 434 435 memset(msg_hdr, 0, sizeof(struct hm_header_st)); 436 437 /* Don't change sequence numbers while listening */ 438 if (!D1I(s)->listen) 439 D1I(s)->handshake_read_seq++; 440 441 s->internal->init_msg = s->internal->init_buf->data + DTLS1_HM_HEADER_LENGTH; 442 return s->internal->init_num; 443 444 f_err: 445 ssl3_send_alert(s, SSL3_AL_FATAL, al); 446 *ok = 0; 447 return -1; 448 } 449 450 451 static int 452 dtls1_preprocess_fragment(SSL *s, struct hm_header_st *msg_hdr, int max) 453 { 454 size_t frag_off, frag_len, msg_len; 455 456 msg_len = msg_hdr->msg_len; 457 frag_off = msg_hdr->frag_off; 458 frag_len = msg_hdr->frag_len; 459 460 /* sanity checking */ 461 if ((frag_off + frag_len) > msg_len) { 462 SSLerror(s, SSL_R_EXCESSIVE_MESSAGE_SIZE); 463 return SSL_AD_ILLEGAL_PARAMETER; 464 } 465 466 if ((frag_off + frag_len) > (unsigned long)max) { 467 SSLerror(s, SSL_R_EXCESSIVE_MESSAGE_SIZE); 468 return SSL_AD_ILLEGAL_PARAMETER; 469 } 470 471 if ( D1I(s)->r_msg_hdr.frag_off == 0) /* first fragment */ 472 { 473 /* 474 * msg_len is limited to 2^24, but is effectively checked 475 * against max above 476 */ 477 if (!BUF_MEM_grow_clean(s->internal->init_buf, 478 msg_len + DTLS1_HM_HEADER_LENGTH)) { 479 SSLerror(s, ERR_R_BUF_LIB); 480 return SSL_AD_INTERNAL_ERROR; 481 } 482 483 S3I(s)->tmp.message_size = msg_len; 484 D1I(s)->r_msg_hdr.msg_len = msg_len; 485 S3I(s)->tmp.message_type = msg_hdr->type; 486 D1I(s)->r_msg_hdr.type = msg_hdr->type; 487 D1I(s)->r_msg_hdr.seq = msg_hdr->seq; 488 } else if (msg_len != D1I(s)->r_msg_hdr.msg_len) { 489 /* 490 * They must be playing with us! BTW, failure to enforce 491 * upper limit would open possibility for buffer overrun. 492 */ 493 SSLerror(s, SSL_R_EXCESSIVE_MESSAGE_SIZE); 494 return SSL_AD_ILLEGAL_PARAMETER; 495 } 496 497 return 0; /* no error */ 498 } 499 500 static int 501 dtls1_retrieve_buffered_fragment(SSL *s, long max, int *ok) 502 { 503 /* 504 * (0) check whether the desired fragment is available 505 * if so: 506 * (1) copy over the fragment to s->internal->init_buf->data[] 507 * (2) update s->internal->init_num 508 */ 509 pitem *item; 510 hm_fragment *frag; 511 int al; 512 513 *ok = 0; 514 item = pqueue_peek(D1I(s)->buffered_messages); 515 if (item == NULL) 516 return 0; 517 518 frag = (hm_fragment *)item->data; 519 520 /* Don't return if reassembly still in progress */ 521 if (frag->reassembly != NULL) 522 return 0; 523 524 if (D1I(s)->handshake_read_seq == frag->msg_header.seq) { 525 unsigned long frag_len = frag->msg_header.frag_len; 526 pqueue_pop(D1I(s)->buffered_messages); 527 528 al = dtls1_preprocess_fragment(s, &frag->msg_header, max); 529 530 if (al == 0) /* no alert */ 531 { 532 unsigned char *p = (unsigned char *)s->internal->init_buf->data + DTLS1_HM_HEADER_LENGTH; 533 memcpy(&p[frag->msg_header.frag_off], 534 frag->fragment, frag->msg_header.frag_len); 535 } 536 537 dtls1_hm_fragment_free(frag); 538 pitem_free(item); 539 540 if (al == 0) { 541 *ok = 1; 542 return frag_len; 543 } 544 545 ssl3_send_alert(s, SSL3_AL_FATAL, al); 546 s->internal->init_num = 0; 547 *ok = 0; 548 return -1; 549 } else 550 return 0; 551 } 552 553 /* 554 * dtls1_max_handshake_message_len returns the maximum number of bytes 555 * permitted in a DTLS handshake message for |s|. The minimum is 16KB, 556 * but may be greater if the maximum certificate list size requires it. 557 */ 558 static unsigned long 559 dtls1_max_handshake_message_len(const SSL *s) 560 { 561 unsigned long max_len; 562 563 max_len = DTLS1_HM_HEADER_LENGTH + SSL3_RT_MAX_ENCRYPTED_LENGTH; 564 if (max_len < (unsigned long)s->internal->max_cert_list) 565 return s->internal->max_cert_list; 566 return max_len; 567 } 568 569 static int 570 dtls1_reassemble_fragment(SSL *s, struct hm_header_st* msg_hdr, int *ok) 571 { 572 hm_fragment *frag = NULL; 573 pitem *item = NULL; 574 int i = -1, is_complete; 575 unsigned char seq64be[8]; 576 unsigned long frag_len = msg_hdr->frag_len; 577 578 if ((msg_hdr->frag_off + frag_len) > msg_hdr->msg_len || 579 msg_hdr->msg_len > dtls1_max_handshake_message_len(s)) 580 goto err; 581 582 if (frag_len == 0) { 583 i = DTLS1_HM_FRAGMENT_RETRY; 584 goto err; 585 } 586 587 /* Try to find item in queue */ 588 memset(seq64be, 0, sizeof(seq64be)); 589 seq64be[6] = (unsigned char)(msg_hdr->seq >> 8); 590 seq64be[7] = (unsigned char)msg_hdr->seq; 591 item = pqueue_find(D1I(s)->buffered_messages, seq64be); 592 593 if (item == NULL) { 594 frag = dtls1_hm_fragment_new(msg_hdr->msg_len, 1); 595 if (frag == NULL) 596 goto err; 597 memcpy(&(frag->msg_header), msg_hdr, sizeof(*msg_hdr)); 598 frag->msg_header.frag_len = frag->msg_header.msg_len; 599 frag->msg_header.frag_off = 0; 600 } else { 601 frag = (hm_fragment*)item->data; 602 if (frag->msg_header.msg_len != msg_hdr->msg_len) { 603 item = NULL; 604 frag = NULL; 605 goto err; 606 } 607 } 608 609 /* 610 * If message is already reassembled, this must be a 611 * retransmit and can be dropped. 612 */ 613 if (frag->reassembly == NULL) { 614 unsigned char devnull [256]; 615 616 while (frag_len) { 617 i = s->method->internal->ssl_read_bytes(s, SSL3_RT_HANDSHAKE, 618 devnull, frag_len > sizeof(devnull) ? 619 sizeof(devnull) : frag_len, 0); 620 if (i <= 0) 621 goto err; 622 frag_len -= i; 623 } 624 i = DTLS1_HM_FRAGMENT_RETRY; 625 goto err; 626 } 627 628 /* read the body of the fragment (header has already been read */ 629 i = s->method->internal->ssl_read_bytes(s, SSL3_RT_HANDSHAKE, 630 frag->fragment + msg_hdr->frag_off, frag_len, 0); 631 if (i <= 0 || (unsigned long)i != frag_len) 632 goto err; 633 634 RSMBLY_BITMASK_MARK(frag->reassembly, (long)msg_hdr->frag_off, 635 (long)(msg_hdr->frag_off + frag_len)); 636 637 RSMBLY_BITMASK_IS_COMPLETE(frag->reassembly, (long)msg_hdr->msg_len, 638 is_complete); 639 640 if (is_complete) { 641 free(frag->reassembly); 642 frag->reassembly = NULL; 643 } 644 645 if (item == NULL) { 646 memset(seq64be, 0, sizeof(seq64be)); 647 seq64be[6] = (unsigned char)(msg_hdr->seq >> 8); 648 seq64be[7] = (unsigned char)(msg_hdr->seq); 649 650 item = pitem_new(seq64be, frag); 651 if (item == NULL) { 652 i = -1; 653 goto err; 654 } 655 656 pqueue_insert(D1I(s)->buffered_messages, item); 657 } 658 659 return DTLS1_HM_FRAGMENT_RETRY; 660 661 err: 662 if (item == NULL && frag != NULL) 663 dtls1_hm_fragment_free(frag); 664 *ok = 0; 665 return i; 666 } 667 668 669 static int 670 dtls1_process_out_of_seq_message(SSL *s, struct hm_header_st* msg_hdr, int *ok) 671 { 672 int i = -1; 673 hm_fragment *frag = NULL; 674 pitem *item = NULL; 675 unsigned char seq64be[8]; 676 unsigned long frag_len = msg_hdr->frag_len; 677 678 if ((msg_hdr->frag_off + frag_len) > msg_hdr->msg_len) 679 goto err; 680 681 /* Try to find item in queue, to prevent duplicate entries */ 682 memset(seq64be, 0, sizeof(seq64be)); 683 seq64be[6] = (unsigned char) (msg_hdr->seq >> 8); 684 seq64be[7] = (unsigned char) msg_hdr->seq; 685 item = pqueue_find(D1I(s)->buffered_messages, seq64be); 686 687 /* 688 * If we already have an entry and this one is a fragment, 689 * don't discard it and rather try to reassemble it. 690 */ 691 if (item != NULL && frag_len < msg_hdr->msg_len) 692 item = NULL; 693 694 /* 695 * Discard the message if sequence number was already there, is 696 * too far in the future, already in the queue or if we received 697 * a FINISHED before the SERVER_HELLO, which then must be a stale 698 * retransmit. 699 */ 700 if (msg_hdr->seq <= D1I(s)->handshake_read_seq || 701 msg_hdr->seq > D1I(s)->handshake_read_seq + 10 || item != NULL || 702 (D1I(s)->handshake_read_seq == 0 && 703 msg_hdr->type == SSL3_MT_FINISHED)) { 704 unsigned char devnull [256]; 705 706 while (frag_len) { 707 i = s->method->internal->ssl_read_bytes(s, SSL3_RT_HANDSHAKE, 708 devnull, frag_len > sizeof(devnull) ? 709 sizeof(devnull) : frag_len, 0); 710 if (i <= 0) 711 goto err; 712 frag_len -= i; 713 } 714 } else { 715 if (frag_len < msg_hdr->msg_len) 716 return dtls1_reassemble_fragment(s, msg_hdr, ok); 717 718 if (frag_len > dtls1_max_handshake_message_len(s)) 719 goto err; 720 721 frag = dtls1_hm_fragment_new(frag_len, 0); 722 if (frag == NULL) 723 goto err; 724 725 memcpy(&(frag->msg_header), msg_hdr, sizeof(*msg_hdr)); 726 727 if (frag_len) { 728 /* read the body of the fragment (header has already been read */ 729 i = s->method->internal->ssl_read_bytes(s, SSL3_RT_HANDSHAKE, 730 frag->fragment, frag_len, 0); 731 if (i <= 0 || (unsigned long)i != frag_len) 732 goto err; 733 } 734 735 memset(seq64be, 0, sizeof(seq64be)); 736 seq64be[6] = (unsigned char)(msg_hdr->seq >> 8); 737 seq64be[7] = (unsigned char)(msg_hdr->seq); 738 739 item = pitem_new(seq64be, frag); 740 if (item == NULL) 741 goto err; 742 743 pqueue_insert(D1I(s)->buffered_messages, item); 744 } 745 746 return DTLS1_HM_FRAGMENT_RETRY; 747 748 err: 749 if (item == NULL && frag != NULL) 750 dtls1_hm_fragment_free(frag); 751 *ok = 0; 752 return i; 753 } 754 755 756 static long 757 dtls1_get_message_fragment(SSL *s, int st1, int stn, long max, int *ok) 758 { 759 unsigned char wire[DTLS1_HM_HEADER_LENGTH]; 760 unsigned long len, frag_off, frag_len; 761 int i, al; 762 struct hm_header_st msg_hdr; 763 764 again: 765 /* see if we have the required fragment already */ 766 if ((frag_len = dtls1_retrieve_buffered_fragment(s, max, ok)) || *ok) { 767 if (*ok) 768 s->internal->init_num = frag_len; 769 return frag_len; 770 } 771 772 /* read handshake message header */ 773 i = s->method->internal->ssl_read_bytes(s, SSL3_RT_HANDSHAKE, wire, 774 DTLS1_HM_HEADER_LENGTH, 0); 775 if (i <= 0) /* nbio, or an error */ 776 { 777 s->internal->rwstate = SSL_READING; 778 *ok = 0; 779 return i; 780 } 781 /* Handshake fails if message header is incomplete */ 782 if (i != DTLS1_HM_HEADER_LENGTH || 783 /* parse the message fragment header */ 784 dtls1_get_message_header(wire, &msg_hdr) == 0) { 785 al = SSL_AD_UNEXPECTED_MESSAGE; 786 SSLerror(s, SSL_R_UNEXPECTED_MESSAGE); 787 goto f_err; 788 } 789 790 /* 791 * if this is a future (or stale) message it gets buffered 792 * (or dropped)--no further processing at this time 793 * While listening, we accept seq 1 (ClientHello with cookie) 794 * although we're still expecting seq 0 (ClientHello) 795 */ 796 if (msg_hdr.seq != D1I(s)->handshake_read_seq && 797 !(D1I(s)->listen && msg_hdr.seq == 1)) 798 return dtls1_process_out_of_seq_message(s, &msg_hdr, ok); 799 800 len = msg_hdr.msg_len; 801 frag_off = msg_hdr.frag_off; 802 frag_len = msg_hdr.frag_len; 803 804 if (frag_len && frag_len < len) 805 return dtls1_reassemble_fragment(s, &msg_hdr, ok); 806 807 if (!s->server && D1I(s)->r_msg_hdr.frag_off == 0 && 808 wire[0] == SSL3_MT_HELLO_REQUEST) { 809 /* 810 * The server may always send 'Hello Request' messages -- 811 * we are doing a handshake anyway now, so ignore them 812 * if their format is correct. Does not count for 813 * 'Finished' MAC. 814 */ 815 if (wire[1] == 0 && wire[2] == 0 && wire[3] == 0) { 816 if (s->internal->msg_callback) 817 s->internal->msg_callback(0, s->version, 818 SSL3_RT_HANDSHAKE, wire, 819 DTLS1_HM_HEADER_LENGTH, s, 820 s->internal->msg_callback_arg); 821 822 s->internal->init_num = 0; 823 goto again; 824 } 825 else /* Incorrectly formated Hello request */ 826 { 827 al = SSL_AD_UNEXPECTED_MESSAGE; 828 SSLerror(s, SSL_R_UNEXPECTED_MESSAGE); 829 goto f_err; 830 } 831 } 832 833 if ((al = dtls1_preprocess_fragment(s, &msg_hdr, max))) 834 goto f_err; 835 836 /* XDTLS: ressurect this when restart is in place */ 837 S3I(s)->hs.state = stn; 838 839 if (frag_len > 0) { 840 unsigned char *p = (unsigned char *)s->internal->init_buf->data + DTLS1_HM_HEADER_LENGTH; 841 842 i = s->method->internal->ssl_read_bytes(s, SSL3_RT_HANDSHAKE, 843 &p[frag_off], frag_len, 0); 844 /* XDTLS: fix this--message fragments cannot span multiple packets */ 845 if (i <= 0) { 846 s->internal->rwstate = SSL_READING; 847 *ok = 0; 848 return i; 849 } 850 } else 851 i = 0; 852 853 /* 854 * XDTLS: an incorrectly formatted fragment should cause the 855 * handshake to fail 856 */ 857 if (i != (int)frag_len) { 858 al = SSL3_AD_ILLEGAL_PARAMETER; 859 SSLerror(s, SSL3_AD_ILLEGAL_PARAMETER); 860 goto f_err; 861 } 862 863 *ok = 1; 864 865 /* 866 * Note that s->internal->init_num is *not* used as current offset in 867 * s->internal->init_buf->data, but as a counter summing up fragments' 868 * lengths: as soon as they sum up to handshake packet 869 * length, we assume we have got all the fragments. 870 */ 871 s->internal->init_num = frag_len; 872 return frag_len; 873 874 f_err: 875 ssl3_send_alert(s, SSL3_AL_FATAL, al); 876 s->internal->init_num = 0; 877 878 *ok = 0; 879 return (-1); 880 } 881 882 int 883 dtls1_read_failed(SSL *s, int code) 884 { 885 if (code > 0) { 886 #ifdef DEBUG 887 fprintf(stderr, "invalid state reached %s:%d", 888 __FILE__, __LINE__); 889 #endif 890 return 1; 891 } 892 893 if (!dtls1_is_timer_expired(s)) { 894 /* 895 * not a timeout, none of our business, let higher layers 896 * handle this. in fact it's probably an error 897 */ 898 return code; 899 } 900 901 if (!SSL_in_init(s)) /* done, no need to send a retransmit */ 902 { 903 BIO_set_flags(SSL_get_rbio(s), BIO_FLAGS_READ); 904 return code; 905 } 906 907 return dtls1_handle_timeout(s); 908 } 909 910 int 911 dtls1_get_queue_priority(unsigned short seq, int is_ccs) 912 { 913 /* 914 * The index of the retransmission queue actually is the message 915 * sequence number, since the queue only contains messages of a 916 * single handshake. However, the ChangeCipherSpec has no message 917 * sequence number and so using only the sequence will result in 918 * the CCS and Finished having the same index. To prevent this, the 919 * sequence number is multiplied by 2. In case of a CCS 1 is 920 * subtracted. This does not only differ CSS and Finished, it also 921 * maintains the order of the index (important for priority queues) 922 * and fits in the unsigned short variable. 923 */ 924 return seq * 2 - is_ccs; 925 } 926 927 int 928 dtls1_retransmit_buffered_messages(SSL *s) 929 { 930 pqueue sent = s->d1->sent_messages; 931 piterator iter; 932 pitem *item; 933 hm_fragment *frag; 934 int found = 0; 935 936 iter = pqueue_iterator(sent); 937 938 for (item = pqueue_next(&iter); item != NULL; 939 item = pqueue_next(&iter)) { 940 frag = (hm_fragment *)item->data; 941 if (dtls1_retransmit_message(s, 942 (unsigned short)dtls1_get_queue_priority( 943 frag->msg_header.seq, frag->msg_header.is_ccs), 0, 944 &found) <= 0 && found) { 945 #ifdef DEBUG 946 fprintf(stderr, "dtls1_retransmit_message() failed\n"); 947 #endif 948 return -1; 949 } 950 } 951 952 return 1; 953 } 954 955 int 956 dtls1_buffer_message(SSL *s, int is_ccs) 957 { 958 pitem *item; 959 hm_fragment *frag; 960 unsigned char seq64be[8]; 961 962 /* Buffer the messsage in order to handle DTLS retransmissions. */ 963 964 /* 965 * This function is called immediately after a message has 966 * been serialized 967 */ 968 OPENSSL_assert(s->internal->init_off == 0); 969 970 frag = dtls1_hm_fragment_new(s->internal->init_num, 0); 971 if (frag == NULL) 972 return 0; 973 974 memcpy(frag->fragment, s->internal->init_buf->data, s->internal->init_num); 975 976 if (is_ccs) { 977 OPENSSL_assert(D1I(s)->w_msg_hdr.msg_len + 978 ((s->version == DTLS1_VERSION) ? 979 DTLS1_CCS_HEADER_LENGTH : 3) == (unsigned int)s->internal->init_num); 980 } else { 981 OPENSSL_assert(D1I(s)->w_msg_hdr.msg_len + 982 DTLS1_HM_HEADER_LENGTH == (unsigned int)s->internal->init_num); 983 } 984 985 frag->msg_header.msg_len = D1I(s)->w_msg_hdr.msg_len; 986 frag->msg_header.seq = D1I(s)->w_msg_hdr.seq; 987 frag->msg_header.type = D1I(s)->w_msg_hdr.type; 988 frag->msg_header.frag_off = 0; 989 frag->msg_header.frag_len = D1I(s)->w_msg_hdr.msg_len; 990 frag->msg_header.is_ccs = is_ccs; 991 992 /* save current state*/ 993 frag->msg_header.saved_retransmit_state.enc_write_ctx = s->internal->enc_write_ctx; 994 frag->msg_header.saved_retransmit_state.write_hash = s->internal->write_hash; 995 frag->msg_header.saved_retransmit_state.session = s->session; 996 frag->msg_header.saved_retransmit_state.epoch = D1I(s)->w_epoch; 997 998 memset(seq64be, 0, sizeof(seq64be)); 999 seq64be[6] = (unsigned char)(dtls1_get_queue_priority( 1000 frag->msg_header.seq, frag->msg_header.is_ccs) >> 8); 1001 seq64be[7] = (unsigned char)(dtls1_get_queue_priority( 1002 frag->msg_header.seq, frag->msg_header.is_ccs)); 1003 1004 item = pitem_new(seq64be, frag); 1005 if (item == NULL) { 1006 dtls1_hm_fragment_free(frag); 1007 return 0; 1008 } 1009 1010 pqueue_insert(s->d1->sent_messages, item); 1011 return 1; 1012 } 1013 1014 int 1015 dtls1_retransmit_message(SSL *s, unsigned short seq, unsigned long frag_off, 1016 int *found) 1017 { 1018 int ret; 1019 /* XDTLS: for now assuming that read/writes are blocking */ 1020 pitem *item; 1021 hm_fragment *frag; 1022 unsigned long header_length; 1023 unsigned char seq64be[8]; 1024 struct dtls1_retransmit_state saved_state; 1025 unsigned char save_write_sequence[8]; 1026 1027 /* 1028 OPENSSL_assert(s->internal->init_num == 0); 1029 OPENSSL_assert(s->internal->init_off == 0); 1030 */ 1031 1032 /* XDTLS: the requested message ought to be found, otherwise error */ 1033 memset(seq64be, 0, sizeof(seq64be)); 1034 seq64be[6] = (unsigned char)(seq >> 8); 1035 seq64be[7] = (unsigned char)seq; 1036 1037 item = pqueue_find(s->d1->sent_messages, seq64be); 1038 if (item == NULL) { 1039 #ifdef DEBUG 1040 fprintf(stderr, "retransmit: message %d non-existent\n", seq); 1041 #endif 1042 *found = 0; 1043 return 0; 1044 } 1045 1046 *found = 1; 1047 frag = (hm_fragment *)item->data; 1048 1049 if (frag->msg_header.is_ccs) 1050 header_length = DTLS1_CCS_HEADER_LENGTH; 1051 else 1052 header_length = DTLS1_HM_HEADER_LENGTH; 1053 1054 memcpy(s->internal->init_buf->data, frag->fragment, 1055 frag->msg_header.msg_len + header_length); 1056 s->internal->init_num = frag->msg_header.msg_len + header_length; 1057 1058 dtls1_set_message_header_int(s, frag->msg_header.type, 1059 frag->msg_header.msg_len, frag->msg_header.seq, 0, 1060 frag->msg_header.frag_len); 1061 1062 /* save current state */ 1063 saved_state.enc_write_ctx = s->internal->enc_write_ctx; 1064 saved_state.write_hash = s->internal->write_hash; 1065 saved_state.session = s->session; 1066 saved_state.epoch = D1I(s)->w_epoch; 1067 1068 D1I(s)->retransmitting = 1; 1069 1070 /* restore state in which the message was originally sent */ 1071 s->internal->enc_write_ctx = frag->msg_header.saved_retransmit_state.enc_write_ctx; 1072 s->internal->write_hash = frag->msg_header.saved_retransmit_state.write_hash; 1073 s->session = frag->msg_header.saved_retransmit_state.session; 1074 D1I(s)->w_epoch = frag->msg_header.saved_retransmit_state.epoch; 1075 1076 if (frag->msg_header.saved_retransmit_state.epoch == 1077 saved_state.epoch - 1) { 1078 memcpy(save_write_sequence, S3I(s)->write_sequence, 1079 sizeof(S3I(s)->write_sequence)); 1080 memcpy(S3I(s)->write_sequence, D1I(s)->last_write_sequence, 1081 sizeof(S3I(s)->write_sequence)); 1082 } 1083 1084 ret = dtls1_do_write(s, frag->msg_header.is_ccs ? 1085 SSL3_RT_CHANGE_CIPHER_SPEC : SSL3_RT_HANDSHAKE); 1086 1087 /* restore current state */ 1088 s->internal->enc_write_ctx = saved_state.enc_write_ctx; 1089 s->internal->write_hash = saved_state.write_hash; 1090 s->session = saved_state.session; 1091 D1I(s)->w_epoch = saved_state.epoch; 1092 1093 if (frag->msg_header.saved_retransmit_state.epoch == 1094 saved_state.epoch - 1) { 1095 memcpy(D1I(s)->last_write_sequence, S3I(s)->write_sequence, 1096 sizeof(S3I(s)->write_sequence)); 1097 memcpy(S3I(s)->write_sequence, save_write_sequence, 1098 sizeof(S3I(s)->write_sequence)); 1099 } 1100 1101 D1I(s)->retransmitting = 0; 1102 1103 (void)BIO_flush(SSL_get_wbio(s)); 1104 return ret; 1105 } 1106 1107 /* call this function when the buffered messages are no longer needed */ 1108 void 1109 dtls1_clear_record_buffer(SSL *s) 1110 { 1111 pitem *item; 1112 1113 for(item = pqueue_pop(s->d1->sent_messages); item != NULL; 1114 item = pqueue_pop(s->d1->sent_messages)) { 1115 dtls1_hm_fragment_free((hm_fragment *)item->data); 1116 pitem_free(item); 1117 } 1118 } 1119 1120 void 1121 dtls1_set_message_header(SSL *s, unsigned char mt, unsigned long len, 1122 unsigned long frag_off, unsigned long frag_len) 1123 { 1124 /* Don't change sequence numbers while listening */ 1125 if (frag_off == 0 && !D1I(s)->listen) { 1126 D1I(s)->handshake_write_seq = D1I(s)->next_handshake_write_seq; 1127 D1I(s)->next_handshake_write_seq++; 1128 } 1129 1130 dtls1_set_message_header_int(s, mt, len, D1I(s)->handshake_write_seq, 1131 frag_off, frag_len); 1132 } 1133 1134 /* don't actually do the writing, wait till the MTU has been retrieved */ 1135 void 1136 dtls1_set_message_header_int(SSL *s, unsigned char mt, unsigned long len, 1137 unsigned short seq_num, unsigned long frag_off, unsigned long frag_len) 1138 { 1139 struct hm_header_st *msg_hdr = &D1I(s)->w_msg_hdr; 1140 1141 msg_hdr->type = mt; 1142 msg_hdr->msg_len = len; 1143 msg_hdr->seq = seq_num; 1144 msg_hdr->frag_off = frag_off; 1145 msg_hdr->frag_len = frag_len; 1146 } 1147 1148 static void 1149 dtls1_fix_message_header(SSL *s, unsigned long frag_off, unsigned long frag_len) 1150 { 1151 struct hm_header_st *msg_hdr = &D1I(s)->w_msg_hdr; 1152 1153 msg_hdr->frag_off = frag_off; 1154 msg_hdr->frag_len = frag_len; 1155 } 1156 1157 static int 1158 dtls1_write_message_header(const struct hm_header_st *msg_hdr, 1159 unsigned long frag_off, unsigned long frag_len, unsigned char *p) 1160 { 1161 CBB cbb; 1162 1163 /* We assume DTLS1_HM_HEADER_LENGTH bytes are available for now... */ 1164 if (!CBB_init_fixed(&cbb, p, DTLS1_HM_HEADER_LENGTH)) 1165 return 0; 1166 if (!CBB_add_u8(&cbb, msg_hdr->type)) 1167 goto err; 1168 if (!CBB_add_u24(&cbb, msg_hdr->msg_len)) 1169 goto err; 1170 if (!CBB_add_u16(&cbb, msg_hdr->seq)) 1171 goto err; 1172 if (!CBB_add_u24(&cbb, frag_off)) 1173 goto err; 1174 if (!CBB_add_u24(&cbb, frag_len)) 1175 goto err; 1176 if (!CBB_finish(&cbb, NULL, NULL)) 1177 goto err; 1178 1179 return 1; 1180 1181 err: 1182 CBB_cleanup(&cbb); 1183 return 0; 1184 } 1185 1186 unsigned int 1187 dtls1_min_mtu(void) 1188 { 1189 return (g_probable_mtu[(sizeof(g_probable_mtu) / 1190 sizeof(g_probable_mtu[0])) - 1]); 1191 } 1192 1193 static unsigned int 1194 dtls1_guess_mtu(unsigned int curr_mtu) 1195 { 1196 unsigned int i; 1197 1198 if (curr_mtu == 0) 1199 return g_probable_mtu[0]; 1200 1201 for (i = 0; i < sizeof(g_probable_mtu) / sizeof(g_probable_mtu[0]); i++) 1202 if (curr_mtu > g_probable_mtu[i]) 1203 return g_probable_mtu[i]; 1204 1205 return curr_mtu; 1206 } 1207 1208 int 1209 dtls1_get_message_header(unsigned char *data, struct hm_header_st *msg_hdr) 1210 { 1211 CBS header; 1212 uint32_t msg_len, frag_off, frag_len; 1213 uint16_t seq; 1214 uint8_t type; 1215 1216 CBS_init(&header, data, sizeof(*msg_hdr)); 1217 1218 memset(msg_hdr, 0, sizeof(*msg_hdr)); 1219 1220 if (!CBS_get_u8(&header, &type)) 1221 return 0; 1222 if (!CBS_get_u24(&header, &msg_len)) 1223 return 0; 1224 if (!CBS_get_u16(&header, &seq)) 1225 return 0; 1226 if (!CBS_get_u24(&header, &frag_off)) 1227 return 0; 1228 if (!CBS_get_u24(&header, &frag_len)) 1229 return 0; 1230 1231 msg_hdr->type = type; 1232 msg_hdr->msg_len = msg_len; 1233 msg_hdr->seq = seq; 1234 msg_hdr->frag_off = frag_off; 1235 msg_hdr->frag_len = frag_len; 1236 1237 return 1; 1238 } 1239 1240 void 1241 dtls1_get_ccs_header(unsigned char *data, struct ccs_header_st *ccs_hdr) 1242 { 1243 memset(ccs_hdr, 0, sizeof(struct ccs_header_st)); 1244 1245 ccs_hdr->type = *(data++); 1246 } 1247