1 /* $OpenBSD: d1_both.c,v 1.24 2014/07/10 08:51:14 tedu 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 <string.h> 118 #include <stdio.h> 119 #include "ssl_locl.h" 120 #include <openssl/buffer.h> 121 #include <openssl/rand.h> 122 #include <openssl/objects.h> 123 #include <openssl/evp.h> 124 #include <openssl/x509.h> 125 126 #include "pqueue.h" 127 128 #define RSMBLY_BITMASK_SIZE(msg_len) (((msg_len) + 7) / 8) 129 130 #define RSMBLY_BITMASK_MARK(bitmask, start, end) { \ 131 if ((end) - (start) <= 8) { \ 132 long ii; \ 133 for (ii = (start); ii < (end); ii++) bitmask[((ii) >> 3)] |= (1 << ((ii) & 7)); \ 134 } else { \ 135 long ii; \ 136 bitmask[((start) >> 3)] |= bitmask_start_values[((start) & 7)]; \ 137 for (ii = (((start) >> 3) + 1); ii < ((((end) - 1)) >> 3); ii++) bitmask[ii] = 0xff; \ 138 bitmask[(((end) - 1) >> 3)] |= bitmask_end_values[((end) & 7)]; \ 139 } } 140 141 #define RSMBLY_BITMASK_IS_COMPLETE(bitmask, msg_len, is_complete) { \ 142 long ii; \ 143 OPENSSL_assert((msg_len) > 0); \ 144 is_complete = 1; \ 145 if (bitmask[(((msg_len) - 1) >> 3)] != bitmask_end_values[((msg_len) & 7)]) is_complete = 0; \ 146 if (is_complete) for (ii = (((msg_len) - 1) >> 3) - 1; ii >= 0 ; ii--) \ 147 if (bitmask[ii] != 0xff) { is_complete = 0; break; } } 148 149 static unsigned char bitmask_start_values[] = { 150 0xff, 0xfe, 0xfc, 0xf8, 0xf0, 0xe0, 0xc0, 0x80 151 }; 152 static unsigned char bitmask_end_values[] = { 153 0xff, 0x01, 0x03, 0x07, 0x0f, 0x1f, 0x3f, 0x7f 154 }; 155 156 /* XDTLS: figure out the right values */ 157 static unsigned int g_probable_mtu[] = {1500 - 28, 512 - 28, 256 - 28}; 158 159 static unsigned int dtls1_guess_mtu(unsigned int curr_mtu); 160 static void dtls1_fix_message_header(SSL *s, unsigned long frag_off, 161 unsigned long frag_len); 162 static unsigned char *dtls1_write_message_header(SSL *s, unsigned char *p); 163 static void dtls1_set_message_header_int(SSL *s, unsigned char mt, 164 unsigned long len, unsigned short seq_num, unsigned long frag_off, 165 unsigned long frag_len); 166 static long dtls1_get_message_fragment(SSL *s, int st1, int stn, long max, 167 int *ok); 168 169 static hm_fragment * 170 dtls1_hm_fragment_new(unsigned long frag_len, int reassembly) 171 { 172 hm_fragment *frag = NULL; 173 unsigned char *buf = NULL; 174 unsigned char *bitmask = NULL; 175 176 frag = malloc(sizeof(hm_fragment)); 177 if (frag == NULL) 178 return NULL; 179 180 if (frag_len) { 181 buf = malloc(frag_len); 182 if (buf == NULL) { 183 free(frag); 184 return NULL; 185 } 186 } 187 188 /* zero length fragment gets zero frag->fragment */ 189 frag->fragment = buf; 190 191 /* Initialize reassembly bitmask if necessary */ 192 if (reassembly) { 193 bitmask = malloc(RSMBLY_BITMASK_SIZE(frag_len)); 194 if (bitmask == NULL) { 195 free(buf); 196 free(frag); 197 return NULL; 198 } 199 memset(bitmask, 0, RSMBLY_BITMASK_SIZE(frag_len)); 200 } 201 202 frag->reassembly = bitmask; 203 204 return frag; 205 } 206 207 static void 208 dtls1_hm_fragment_free(hm_fragment *frag) 209 { 210 211 if (frag->msg_header.is_ccs) { 212 EVP_CIPHER_CTX_free( 213 frag->msg_header.saved_retransmit_state.enc_write_ctx); 214 EVP_MD_CTX_destroy( 215 frag->msg_header.saved_retransmit_state.write_hash); 216 } 217 free(frag->fragment); 218 free(frag->reassembly); 219 free(frag); 220 } 221 222 /* send s->init_buf in records of type 'type' (SSL3_RT_HANDSHAKE or SSL3_RT_CHANGE_CIPHER_SPEC) */ 223 int 224 dtls1_do_write(SSL *s, int type) 225 { 226 int ret; 227 int curr_mtu; 228 unsigned int len, frag_off, mac_size, blocksize; 229 230 /* AHA! Figure out the MTU, and stick to the right size */ 231 if (s->d1->mtu < dtls1_min_mtu() && 232 !(SSL_get_options(s) & SSL_OP_NO_QUERY_MTU)) { 233 s->d1->mtu = BIO_ctrl(SSL_get_wbio(s), 234 BIO_CTRL_DGRAM_QUERY_MTU, 0, NULL); 235 236 /* 237 * I've seen the kernel return bogus numbers when it 238 * doesn't know the MTU (ie., the initial write), so just 239 * make sure we have a reasonable number 240 */ 241 if (s->d1->mtu < dtls1_min_mtu()) { 242 s->d1->mtu = 0; 243 s->d1->mtu = dtls1_guess_mtu(s->d1->mtu); 244 BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SET_MTU, 245 s->d1->mtu, NULL); 246 } 247 } 248 249 OPENSSL_assert(s->d1->mtu >= dtls1_min_mtu()); 250 /* should have something reasonable now */ 251 252 if (s->init_off == 0 && type == SSL3_RT_HANDSHAKE) 253 OPENSSL_assert(s->init_num == 254 (int)s->d1->w_msg_hdr.msg_len + DTLS1_HM_HEADER_LENGTH); 255 256 if (s->write_hash) 257 mac_size = EVP_MD_CTX_size(s->write_hash); 258 else 259 mac_size = 0; 260 261 if (s->enc_write_ctx && 262 (EVP_CIPHER_mode( s->enc_write_ctx->cipher) & EVP_CIPH_CBC_MODE)) 263 blocksize = 2 * EVP_CIPHER_block_size(s->enc_write_ctx->cipher); 264 else 265 blocksize = 0; 266 267 frag_off = 0; 268 while (s->init_num) { 269 curr_mtu = s->d1->mtu - BIO_wpending(SSL_get_wbio(s)) - 270 DTLS1_RT_HEADER_LENGTH - mac_size - blocksize; 271 272 if (curr_mtu <= DTLS1_HM_HEADER_LENGTH) { 273 /* grr.. we could get an error if MTU picked was wrong */ 274 ret = BIO_flush(SSL_get_wbio(s)); 275 if (ret <= 0) 276 return ret; 277 curr_mtu = s->d1->mtu - DTLS1_RT_HEADER_LENGTH - 278 mac_size - blocksize; 279 } 280 281 if (s->init_num > curr_mtu) 282 len = curr_mtu; 283 else 284 len = s->init_num; 285 286 287 /* XDTLS: this function is too long. split out the CCS part */ 288 if (type == SSL3_RT_HANDSHAKE) { 289 if (s->init_off != 0) { 290 OPENSSL_assert(s->init_off > DTLS1_HM_HEADER_LENGTH); 291 s->init_off -= DTLS1_HM_HEADER_LENGTH; 292 s->init_num += DTLS1_HM_HEADER_LENGTH; 293 294 if (s->init_num > curr_mtu) 295 len = curr_mtu; 296 else 297 len = s->init_num; 298 } 299 300 dtls1_fix_message_header(s, frag_off, 301 len - DTLS1_HM_HEADER_LENGTH); 302 303 dtls1_write_message_header(s, 304 (unsigned char *)&s->init_buf->data[s->init_off]); 305 306 OPENSSL_assert(len >= DTLS1_HM_HEADER_LENGTH); 307 } 308 309 ret = dtls1_write_bytes(s, type, 310 &s->init_buf->data[s->init_off], len); 311 if (ret < 0) { 312 /* 313 * Might need to update MTU here, but we don't know 314 * which previous packet caused the failure -- so 315 * can't really retransmit anything. continue as 316 * if everything is fine and wait for an alert to 317 * handle the retransmit 318 */ 319 if (BIO_ctrl(SSL_get_wbio(s), 320 BIO_CTRL_DGRAM_MTU_EXCEEDED, 0, NULL) > 0) 321 s->d1->mtu = BIO_ctrl(SSL_get_wbio(s), 322 BIO_CTRL_DGRAM_QUERY_MTU, 0, NULL); 323 else 324 return (-1); 325 } else { 326 327 /* 328 * Bad if this assert fails, only part of the 329 * handshake message got sent. but why would 330 * this happen? 331 */ 332 OPENSSL_assert(len == (unsigned int)ret); 333 334 if (type == SSL3_RT_HANDSHAKE && 335 !s->d1->retransmitting) { 336 /* 337 * Should not be done for 'Hello Request's, 338 * but in that case we'll ignore the result 339 * anyway 340 */ 341 unsigned char *p = (unsigned char *)&s->init_buf->data[s->init_off]; 342 const struct hm_header_st *msg_hdr = &s->d1->w_msg_hdr; 343 int xlen; 344 345 if (frag_off == 0 && 346 s->version != DTLS1_BAD_VER) { 347 /* 348 * Reconstruct message header is if it 349 * is being sent in single fragment 350 */ 351 *p++ = msg_hdr->type; 352 l2n3(msg_hdr->msg_len, p); 353 s2n (msg_hdr->seq, p); 354 l2n3(0, p); 355 l2n3(msg_hdr->msg_len, p); 356 p -= DTLS1_HM_HEADER_LENGTH; 357 xlen = ret; 358 } else { 359 p += DTLS1_HM_HEADER_LENGTH; 360 xlen = ret - DTLS1_HM_HEADER_LENGTH; 361 } 362 363 ssl3_finish_mac(s, p, xlen); 364 } 365 366 if (ret == s->init_num) { 367 if (s->msg_callback) 368 s->msg_callback(1, s->version, type, 369 s->init_buf->data, 370 (size_t)(s->init_off + s->init_num), 371 s, s->msg_callback_arg); 372 373 s->init_off = 0; 374 /* done writing this message */ 375 s->init_num = 0; 376 377 return (1); 378 } 379 s->init_off += ret; 380 s->init_num -= ret; 381 frag_off += (ret -= DTLS1_HM_HEADER_LENGTH); 382 } 383 } 384 return (0); 385 } 386 387 388 /* 389 * Obtain handshake message of message type 'mt' (any if mt == -1), 390 * maximum acceptable body length 'max'. 391 * Read an entire handshake message. Handshake messages arrive in 392 * fragments. 393 */ 394 long 395 dtls1_get_message(SSL *s, int st1, int stn, int mt, long max, int *ok) 396 { 397 int i, al; 398 struct hm_header_st *msg_hdr; 399 unsigned char *p; 400 unsigned long msg_len; 401 402 /* 403 * s3->tmp is used to store messages that are unexpected, caused 404 * by the absence of an optional handshake message 405 */ 406 if (s->s3->tmp.reuse_message) { 407 s->s3->tmp.reuse_message = 0; 408 if ((mt >= 0) && (s->s3->tmp.message_type != mt)) { 409 al = SSL_AD_UNEXPECTED_MESSAGE; 410 SSLerr(SSL_F_DTLS1_GET_MESSAGE, 411 SSL_R_UNEXPECTED_MESSAGE); 412 goto f_err; 413 } 414 *ok = 1; 415 s->init_msg = s->init_buf->data + DTLS1_HM_HEADER_LENGTH; 416 s->init_num = (int)s->s3->tmp.message_size; 417 return s->init_num; 418 } 419 420 msg_hdr = &s->d1->r_msg_hdr; 421 memset(msg_hdr, 0x00, sizeof(struct hm_header_st)); 422 423 again: 424 i = dtls1_get_message_fragment(s, st1, stn, max, ok); 425 if (i == DTLS1_HM_BAD_FRAGMENT || 426 i == DTLS1_HM_FRAGMENT_RETRY) /* bad fragment received */ 427 goto again; 428 else if (i <= 0 && !*ok) 429 return i; 430 431 p = (unsigned char *)s->init_buf->data; 432 msg_len = msg_hdr->msg_len; 433 434 /* reconstruct message header */ 435 *(p++) = msg_hdr->type; 436 l2n3(msg_len, p); 437 s2n (msg_hdr->seq, p); 438 l2n3(0, p); 439 l2n3(msg_len, p); 440 if (s->version != DTLS1_BAD_VER) { 441 p -= DTLS1_HM_HEADER_LENGTH; 442 msg_len += DTLS1_HM_HEADER_LENGTH; 443 } 444 445 ssl3_finish_mac(s, p, msg_len); 446 if (s->msg_callback) 447 s->msg_callback(0, s->version, SSL3_RT_HANDSHAKE, p, msg_len, 448 s, s->msg_callback_arg); 449 450 memset(msg_hdr, 0x00, sizeof(struct hm_header_st)); 451 452 /* Don't change sequence numbers while listening */ 453 if (!s->d1->listen) 454 s->d1->handshake_read_seq++; 455 456 s->init_msg = s->init_buf->data + DTLS1_HM_HEADER_LENGTH; 457 return s->init_num; 458 459 f_err: 460 ssl3_send_alert(s, SSL3_AL_FATAL, al); 461 *ok = 0; 462 return -1; 463 } 464 465 466 static int 467 dtls1_preprocess_fragment(SSL *s, struct hm_header_st *msg_hdr, int max) 468 { 469 size_t frag_off, frag_len, msg_len; 470 471 msg_len = msg_hdr->msg_len; 472 frag_off = msg_hdr->frag_off; 473 frag_len = msg_hdr->frag_len; 474 475 /* sanity checking */ 476 if ((frag_off + frag_len) > msg_len) { 477 SSLerr(SSL_F_DTLS1_PREPROCESS_FRAGMENT, 478 SSL_R_EXCESSIVE_MESSAGE_SIZE); 479 return SSL_AD_ILLEGAL_PARAMETER; 480 } 481 482 if ((frag_off + frag_len) > (unsigned long)max) { 483 SSLerr(SSL_F_DTLS1_PREPROCESS_FRAGMENT, 484 SSL_R_EXCESSIVE_MESSAGE_SIZE); 485 return SSL_AD_ILLEGAL_PARAMETER; 486 } 487 488 if ( s->d1->r_msg_hdr.frag_off == 0) /* first fragment */ 489 { 490 /* 491 * msg_len is limited to 2^24, but is effectively checked 492 * against max above 493 */ 494 if (!BUF_MEM_grow_clean(s->init_buf, 495 msg_len + DTLS1_HM_HEADER_LENGTH)) { 496 SSLerr(SSL_F_DTLS1_PREPROCESS_FRAGMENT, ERR_R_BUF_LIB); 497 return SSL_AD_INTERNAL_ERROR; 498 } 499 500 s->s3->tmp.message_size = msg_len; 501 s->d1->r_msg_hdr.msg_len = msg_len; 502 s->s3->tmp.message_type = msg_hdr->type; 503 s->d1->r_msg_hdr.type = msg_hdr->type; 504 s->d1->r_msg_hdr.seq = msg_hdr->seq; 505 } else if (msg_len != s->d1->r_msg_hdr.msg_len) { 506 /* 507 * They must be playing with us! BTW, failure to enforce 508 * upper limit would open possibility for buffer overrun. 509 */ 510 SSLerr(SSL_F_DTLS1_PREPROCESS_FRAGMENT, 511 SSL_R_EXCESSIVE_MESSAGE_SIZE); 512 return SSL_AD_ILLEGAL_PARAMETER; 513 } 514 515 return 0; /* no error */ 516 } 517 518 static int 519 dtls1_retrieve_buffered_fragment(SSL *s, long max, int *ok) 520 { 521 /* 522 * (0) check whether the desired fragment is available 523 * if so: 524 * (1) copy over the fragment to s->init_buf->data[] 525 * (2) update s->init_num 526 */ 527 pitem *item; 528 hm_fragment *frag; 529 int al; 530 531 *ok = 0; 532 item = pqueue_peek(s->d1->buffered_messages); 533 if (item == NULL) 534 return 0; 535 536 frag = (hm_fragment *)item->data; 537 538 /* Don't return if reassembly still in progress */ 539 if (frag->reassembly != NULL) 540 return 0; 541 542 if (s->d1->handshake_read_seq == frag->msg_header.seq) { 543 unsigned long frag_len = frag->msg_header.frag_len; 544 pqueue_pop(s->d1->buffered_messages); 545 546 al = dtls1_preprocess_fragment(s, &frag->msg_header, max); 547 548 if (al == 0) /* no alert */ 549 { 550 unsigned char *p = (unsigned char *)s->init_buf->data + DTLS1_HM_HEADER_LENGTH; 551 memcpy(&p[frag->msg_header.frag_off], 552 frag->fragment, frag->msg_header.frag_len); 553 } 554 555 dtls1_hm_fragment_free(frag); 556 pitem_free(item); 557 558 if (al == 0) { 559 *ok = 1; 560 return frag_len; 561 } 562 563 ssl3_send_alert(s, SSL3_AL_FATAL, al); 564 s->init_num = 0; 565 *ok = 0; 566 return -1; 567 } else 568 return 0; 569 } 570 571 572 static int 573 dtls1_reassemble_fragment(SSL *s, struct hm_header_st* msg_hdr, int *ok) 574 { 575 hm_fragment *frag = NULL; 576 pitem *item = NULL; 577 int i = -1, is_complete; 578 unsigned char seq64be[8]; 579 unsigned long frag_len = msg_hdr->frag_len, max_len; 580 581 if ((msg_hdr->frag_off + frag_len) > msg_hdr->msg_len) 582 goto err; 583 584 /* 585 * Determine maximum allowed message size. Depends on (user set) 586 * maximum certificate length, but 16k is minimum. 587 */ 588 if (DTLS1_HM_HEADER_LENGTH + SSL3_RT_MAX_ENCRYPTED_LENGTH < 589 s->max_cert_list) 590 max_len = s->max_cert_list; 591 else 592 max_len = DTLS1_HM_HEADER_LENGTH + SSL3_RT_MAX_ENCRYPTED_LENGTH; 593 594 if ((msg_hdr->frag_off + frag_len) > max_len) 595 goto err; 596 597 /* Try to find item in queue */ 598 memset(seq64be, 0, sizeof(seq64be)); 599 seq64be[6] = (unsigned char)(msg_hdr->seq >> 8); 600 seq64be[7] = (unsigned char)msg_hdr->seq; 601 item = pqueue_find(s->d1->buffered_messages, seq64be); 602 603 if (item == NULL) { 604 frag = dtls1_hm_fragment_new(msg_hdr->msg_len, 1); 605 if (frag == NULL) 606 goto err; 607 memcpy(&(frag->msg_header), msg_hdr, sizeof(*msg_hdr)); 608 frag->msg_header.frag_len = frag->msg_header.msg_len; 609 frag->msg_header.frag_off = 0; 610 } else { 611 frag = (hm_fragment*)item->data; 612 if (frag->msg_header.msg_len != msg_hdr->msg_len) { 613 item = NULL; 614 frag = NULL; 615 goto err; 616 } 617 } 618 619 /* 620 * If message is already reassembled, this must be a 621 * retransmit and can be dropped. 622 */ 623 if (frag->reassembly == NULL) { 624 unsigned char devnull [256]; 625 626 while (frag_len) { 627 i = s->method->ssl_read_bytes(s, SSL3_RT_HANDSHAKE, 628 devnull, frag_len > sizeof(devnull) ? 629 sizeof(devnull) : frag_len, 0); 630 if (i <= 0) 631 goto err; 632 frag_len -= i; 633 } 634 i = DTLS1_HM_FRAGMENT_RETRY; 635 goto err; 636 } 637 638 /* read the body of the fragment (header has already been read */ 639 i = s->method->ssl_read_bytes(s, SSL3_RT_HANDSHAKE, 640 frag->fragment + msg_hdr->frag_off, frag_len, 0); 641 if (i <= 0 || (unsigned long)i != frag_len) 642 goto err; 643 644 RSMBLY_BITMASK_MARK(frag->reassembly, (long)msg_hdr->frag_off, 645 (long)(msg_hdr->frag_off + frag_len)); 646 647 RSMBLY_BITMASK_IS_COMPLETE(frag->reassembly, (long)msg_hdr->msg_len, 648 is_complete); 649 650 if (is_complete) { 651 free(frag->reassembly); 652 frag->reassembly = NULL; 653 } 654 655 if (item == NULL) { 656 memset(seq64be, 0, sizeof(seq64be)); 657 seq64be[6] = (unsigned char)(msg_hdr->seq >> 8); 658 seq64be[7] = (unsigned char)(msg_hdr->seq); 659 660 item = pitem_new(seq64be, frag); 661 if (item == NULL) { 662 i = -1; 663 goto err; 664 } 665 666 pqueue_insert(s->d1->buffered_messages, item); 667 } 668 669 return DTLS1_HM_FRAGMENT_RETRY; 670 671 err: 672 if (item == NULL && frag != NULL) 673 dtls1_hm_fragment_free(frag); 674 *ok = 0; 675 return i; 676 } 677 678 679 static int 680 dtls1_process_out_of_seq_message(SSL *s, struct hm_header_st* msg_hdr, int *ok) 681 { 682 int i = -1; 683 hm_fragment *frag = NULL; 684 pitem *item = NULL; 685 unsigned char seq64be[8]; 686 unsigned long frag_len = msg_hdr->frag_len; 687 688 if ((msg_hdr->frag_off + frag_len) > msg_hdr->msg_len) 689 goto err; 690 691 /* Try to find item in queue, to prevent duplicate entries */ 692 memset(seq64be, 0, sizeof(seq64be)); 693 seq64be[6] = (unsigned char) (msg_hdr->seq >> 8); 694 seq64be[7] = (unsigned char) msg_hdr->seq; 695 item = pqueue_find(s->d1->buffered_messages, seq64be); 696 697 /* 698 * If we already have an entry and this one is a fragment, 699 * don't discard it and rather try to reassemble it. 700 */ 701 if (item != NULL && frag_len < msg_hdr->msg_len) 702 item = NULL; 703 704 /* 705 * Discard the message if sequence number was already there, is 706 * too far in the future, already in the queue or if we received 707 * a FINISHED before the SERVER_HELLO, which then must be a stale 708 * retransmit. 709 */ 710 if (msg_hdr->seq <= s->d1->handshake_read_seq || 711 msg_hdr->seq > s->d1->handshake_read_seq + 10 || item != NULL || 712 (s->d1->handshake_read_seq == 0 && 713 msg_hdr->type == SSL3_MT_FINISHED)) { 714 unsigned char devnull [256]; 715 716 while (frag_len) { 717 i = s->method->ssl_read_bytes(s, SSL3_RT_HANDSHAKE, 718 devnull, frag_len > sizeof(devnull) ? 719 sizeof(devnull) : frag_len, 0); 720 if (i <= 0) 721 goto err; 722 frag_len -= i; 723 } 724 } else { 725 if (frag_len && frag_len < msg_hdr->msg_len) 726 return dtls1_reassemble_fragment(s, msg_hdr, ok); 727 728 frag = dtls1_hm_fragment_new(frag_len, 0); 729 if (frag == NULL) 730 goto err; 731 732 memcpy(&(frag->msg_header), msg_hdr, sizeof(*msg_hdr)); 733 734 if (frag_len) { 735 /* read the body of the fragment (header has already been read */ 736 i = s->method->ssl_read_bytes(s, SSL3_RT_HANDSHAKE, 737 frag->fragment, frag_len, 0); 738 if (i <= 0 || (unsigned long)i != frag_len) 739 goto err; 740 } 741 742 memset(seq64be, 0, sizeof(seq64be)); 743 seq64be[6] = (unsigned char)(msg_hdr->seq >> 8); 744 seq64be[7] = (unsigned char)(msg_hdr->seq); 745 746 item = pitem_new(seq64be, frag); 747 if (item == NULL) 748 goto err; 749 750 pqueue_insert(s->d1->buffered_messages, item); 751 } 752 753 return DTLS1_HM_FRAGMENT_RETRY; 754 755 err: 756 if (item == NULL && frag != NULL) 757 dtls1_hm_fragment_free(frag); 758 *ok = 0; 759 return i; 760 } 761 762 763 static long 764 dtls1_get_message_fragment(SSL *s, int st1, int stn, long max, int *ok) 765 { 766 unsigned char wire[DTLS1_HM_HEADER_LENGTH]; 767 unsigned long len, frag_off, frag_len; 768 int i, al; 769 struct hm_header_st msg_hdr; 770 771 again: 772 /* see if we have the required fragment already */ 773 if ((frag_len = dtls1_retrieve_buffered_fragment(s, max, ok)) || *ok) { 774 if (*ok) 775 s->init_num = frag_len; 776 return frag_len; 777 } 778 779 /* read handshake message header */ 780 i = s->method->ssl_read_bytes(s, SSL3_RT_HANDSHAKE, wire, 781 DTLS1_HM_HEADER_LENGTH, 0); 782 if (i <= 0) /* nbio, or an error */ 783 { 784 s->rwstate = SSL_READING; 785 *ok = 0; 786 return i; 787 } 788 /* Handshake fails if message header is incomplete */ 789 if (i != DTLS1_HM_HEADER_LENGTH) { 790 al = SSL_AD_UNEXPECTED_MESSAGE; 791 SSLerr(SSL_F_DTLS1_GET_MESSAGE_FRAGMENT, 792 SSL_R_UNEXPECTED_MESSAGE); 793 goto f_err; 794 } 795 796 /* parse the message fragment header */ 797 dtls1_get_message_header(wire, &msg_hdr); 798 799 /* 800 * if this is a future (or stale) message it gets buffered 801 * (or dropped)--no further processing at this time 802 * While listening, we accept seq 1 (ClientHello with cookie) 803 * although we're still expecting seq 0 (ClientHello) 804 */ 805 if (msg_hdr.seq != s->d1->handshake_read_seq && 806 !(s->d1->listen && msg_hdr.seq == 1)) 807 return dtls1_process_out_of_seq_message(s, &msg_hdr, ok); 808 809 len = msg_hdr.msg_len; 810 frag_off = msg_hdr.frag_off; 811 frag_len = msg_hdr.frag_len; 812 813 if (frag_len && frag_len < len) 814 return dtls1_reassemble_fragment(s, &msg_hdr, ok); 815 816 if (!s->server && s->d1->r_msg_hdr.frag_off == 0 && 817 wire[0] == SSL3_MT_HELLO_REQUEST) { 818 /* 819 * The server may always send 'Hello Request' messages -- 820 * we are doing a handshake anyway now, so ignore them 821 * if their format is correct. Does not count for 822 * 'Finished' MAC. 823 */ 824 if (wire[1] == 0 && wire[2] == 0 && wire[3] == 0) { 825 if (s->msg_callback) 826 s->msg_callback(0, s->version, 827 SSL3_RT_HANDSHAKE, wire, 828 DTLS1_HM_HEADER_LENGTH, s, 829 s->msg_callback_arg); 830 831 s->init_num = 0; 832 goto again; 833 } 834 else /* Incorrectly formated Hello request */ 835 { 836 al = SSL_AD_UNEXPECTED_MESSAGE; 837 SSLerr(SSL_F_DTLS1_GET_MESSAGE_FRAGMENT, 838 SSL_R_UNEXPECTED_MESSAGE); 839 goto f_err; 840 } 841 } 842 843 if ((al = dtls1_preprocess_fragment(s, &msg_hdr, max))) 844 goto f_err; 845 846 /* XDTLS: ressurect this when restart is in place */ 847 s->state = stn; 848 849 if (frag_len > 0) { 850 unsigned char *p = (unsigned char *)s->init_buf->data + DTLS1_HM_HEADER_LENGTH; 851 852 i = s->method->ssl_read_bytes(s, SSL3_RT_HANDSHAKE, 853 &p[frag_off], frag_len, 0); 854 /* XDTLS: fix this--message fragments cannot span multiple packets */ 855 if (i <= 0) { 856 s->rwstate = SSL_READING; 857 *ok = 0; 858 return i; 859 } 860 } else 861 i = 0; 862 863 /* 864 * XDTLS: an incorrectly formatted fragment should cause the 865 * handshake to fail 866 */ 867 if (i != (int)frag_len) { 868 al = SSL3_AD_ILLEGAL_PARAMETER; 869 SSLerr(SSL_F_DTLS1_GET_MESSAGE_FRAGMENT, 870 SSL3_AD_ILLEGAL_PARAMETER); 871 goto f_err; 872 } 873 874 *ok = 1; 875 876 /* 877 * Note that s->init_num is *not* used as current offset in 878 * s->init_buf->data, but as a counter summing up fragments' 879 * lengths: as soon as they sum up to handshake packet 880 * length, we assume we have got all the fragments. 881 */ 882 s->init_num = frag_len; 883 return frag_len; 884 885 f_err: 886 ssl3_send_alert(s, SSL3_AL_FATAL, al); 887 s->init_num = 0; 888 889 *ok = 0; 890 return (-1); 891 } 892 893 int 894 dtls1_send_finished(SSL *s, int a, int b, const char *sender, int slen) 895 { 896 unsigned char *p, *d; 897 int i; 898 unsigned long l; 899 900 if (s->state == a) { 901 d = (unsigned char *)s->init_buf->data; 902 p = &(d[DTLS1_HM_HEADER_LENGTH]); 903 904 i = s->method->ssl3_enc->final_finish_mac(s, sender, slen, 905 s->s3->tmp.finish_md); 906 s->s3->tmp.finish_md_len = i; 907 memcpy(p, s->s3->tmp.finish_md, i); 908 p += i; 909 l = i; 910 911 /* 912 * Copy the finished so we can use it for 913 * renegotiation checks 914 */ 915 if (s->type == SSL_ST_CONNECT) { 916 OPENSSL_assert(i <= EVP_MAX_MD_SIZE); 917 memcpy(s->s3->previous_client_finished, 918 s->s3->tmp.finish_md, i); 919 s->s3->previous_client_finished_len = i; 920 } else { 921 OPENSSL_assert(i <= EVP_MAX_MD_SIZE); 922 memcpy(s->s3->previous_server_finished, 923 s->s3->tmp.finish_md, i); 924 s->s3->previous_server_finished_len = i; 925 } 926 927 d = dtls1_set_message_header(s, d, SSL3_MT_FINISHED, l, 0, l); 928 s->init_num = (int)l + DTLS1_HM_HEADER_LENGTH; 929 s->init_off = 0; 930 931 /* buffer the message to handle re-xmits */ 932 dtls1_buffer_message(s, 0); 933 934 s->state = b; 935 } 936 937 /* SSL3_ST_SEND_xxxxxx_HELLO_B */ 938 return (dtls1_do_write(s, SSL3_RT_HANDSHAKE)); 939 } 940 941 /* 942 * for these 2 messages, we need to 943 * ssl->enc_read_ctx re-init 944 * ssl->s3->read_sequence zero 945 * ssl->s3->read_mac_secret re-init 946 * ssl->session->read_sym_enc assign 947 * ssl->session->read_hash assign 948 */ 949 int 950 dtls1_send_change_cipher_spec(SSL *s, int a, int b) 951 { 952 unsigned char *p; 953 954 if (s->state == a) { 955 p = (unsigned char *)s->init_buf->data; 956 *p++=SSL3_MT_CCS; 957 s->d1->handshake_write_seq = s->d1->next_handshake_write_seq; 958 s->init_num = DTLS1_CCS_HEADER_LENGTH; 959 960 if (s->version == DTLS1_BAD_VER) { 961 s->d1->next_handshake_write_seq++; 962 s2n(s->d1->handshake_write_seq, p); 963 s->init_num += 2; 964 } 965 966 s->init_off = 0; 967 968 dtls1_set_message_header_int(s, SSL3_MT_CCS, 0, 969 s->d1->handshake_write_seq, 0, 0); 970 971 /* buffer the message to handle re-xmits */ 972 dtls1_buffer_message(s, 1); 973 974 s->state = b; 975 } 976 977 /* SSL3_ST_CW_CHANGE_B */ 978 return (dtls1_do_write(s, SSL3_RT_CHANGE_CIPHER_SPEC)); 979 } 980 981 static int 982 dtls1_add_cert_to_buf(BUF_MEM *buf, unsigned long *l, X509 *x) 983 { 984 int n; 985 unsigned char *p; 986 987 n = i2d_X509(x, NULL); 988 if (!BUF_MEM_grow_clean(buf, n + (*l) + 3)) { 989 SSLerr(SSL_F_DTLS1_ADD_CERT_TO_BUF, ERR_R_BUF_LIB); 990 return 0; 991 } 992 p = (unsigned char *)&(buf->data[*l]); 993 l2n3(n, p); 994 i2d_X509(x, &p); 995 *l += n + 3; 996 997 return 1; 998 } 999 1000 unsigned long 1001 dtls1_output_cert_chain(SSL *s, X509 *x) 1002 { 1003 unsigned char *p; 1004 int i; 1005 unsigned long l = 3 + DTLS1_HM_HEADER_LENGTH; 1006 BUF_MEM *buf; 1007 1008 /* TLSv1 sends a chain with nothing in it, instead of an alert */ 1009 buf = s->init_buf; 1010 if (!BUF_MEM_grow_clean(buf, 10)) { 1011 SSLerr(SSL_F_DTLS1_OUTPUT_CERT_CHAIN, ERR_R_BUF_LIB); 1012 return (0); 1013 } 1014 if (x != NULL) { 1015 X509_STORE_CTX xs_ctx; 1016 1017 if (!X509_STORE_CTX_init(&xs_ctx, s->ctx->cert_store, 1018 x, NULL)) { 1019 SSLerr(SSL_F_DTLS1_OUTPUT_CERT_CHAIN, ERR_R_X509_LIB); 1020 return (0); 1021 } 1022 1023 X509_verify_cert(&xs_ctx); 1024 /* Don't leave errors in the queue */ 1025 ERR_clear_error(); 1026 for (i = 0; i < sk_X509_num(xs_ctx.chain); i++) { 1027 x = sk_X509_value(xs_ctx.chain, i); 1028 1029 if (!dtls1_add_cert_to_buf(buf, &l, x)) { 1030 X509_STORE_CTX_cleanup(&xs_ctx); 1031 return 0; 1032 } 1033 } 1034 X509_STORE_CTX_cleanup(&xs_ctx); 1035 } 1036 /* Thawte special :-) */ 1037 for (i = 0; i < sk_X509_num(s->ctx->extra_certs); i++) { 1038 x = sk_X509_value(s->ctx->extra_certs, i); 1039 if (!dtls1_add_cert_to_buf(buf, &l, x)) 1040 return 0; 1041 } 1042 1043 l -= (3 + DTLS1_HM_HEADER_LENGTH); 1044 1045 p = (unsigned char *)&(buf->data[DTLS1_HM_HEADER_LENGTH]); 1046 l2n3(l, p); 1047 l += 3; 1048 p = (unsigned char *)&(buf->data[0]); 1049 p = dtls1_set_message_header(s, p, SSL3_MT_CERTIFICATE, l, 0, l); 1050 1051 l += DTLS1_HM_HEADER_LENGTH; 1052 return (l); 1053 } 1054 1055 int 1056 dtls1_read_failed(SSL *s, int code) 1057 { 1058 if (code > 0) { 1059 fprintf(stderr, "invalid state reached %s:%d", 1060 __FILE__, __LINE__); 1061 return 1; 1062 } 1063 1064 if (!dtls1_is_timer_expired(s)) { 1065 /* 1066 * not a timeout, none of our business, let higher layers 1067 * handle this. in fact it's probably an error 1068 */ 1069 return code; 1070 } 1071 1072 if (!SSL_in_init(s)) /* done, no need to send a retransmit */ 1073 { 1074 BIO_set_flags(SSL_get_rbio(s), BIO_FLAGS_READ); 1075 return code; 1076 } 1077 1078 return dtls1_handle_timeout(s); 1079 } 1080 1081 int 1082 dtls1_get_queue_priority(unsigned short seq, int is_ccs) 1083 { 1084 /* 1085 * The index of the retransmission queue actually is the message 1086 * sequence number, since the queue only contains messages of a 1087 * single handshake. However, the ChangeCipherSpec has no message 1088 * sequence number and so using only the sequence will result in 1089 * the CCS and Finished having the same index. To prevent this, the 1090 * sequence number is multiplied by 2. In case of a CCS 1 is 1091 * subtracted. This does not only differ CSS and Finished, it also 1092 * maintains the order of the index (important for priority queues) 1093 * and fits in the unsigned short variable. 1094 */ 1095 return seq * 2 - is_ccs; 1096 } 1097 1098 int 1099 dtls1_retransmit_buffered_messages(SSL *s) 1100 { 1101 pqueue sent = s->d1->sent_messages; 1102 piterator iter; 1103 pitem *item; 1104 hm_fragment *frag; 1105 int found = 0; 1106 1107 iter = pqueue_iterator(sent); 1108 1109 for (item = pqueue_next(&iter); item != NULL; 1110 item = pqueue_next(&iter)) { 1111 frag = (hm_fragment *)item->data; 1112 if (dtls1_retransmit_message(s, 1113 (unsigned short)dtls1_get_queue_priority( 1114 frag->msg_header.seq, frag->msg_header.is_ccs), 0, 1115 &found) <= 0 && found) { 1116 fprintf(stderr, "dtls1_retransmit_message() failed\n"); 1117 return -1; 1118 } 1119 } 1120 1121 return 1; 1122 } 1123 1124 int 1125 dtls1_buffer_message(SSL *s, int is_ccs) 1126 { 1127 pitem *item; 1128 hm_fragment *frag; 1129 unsigned char seq64be[8]; 1130 1131 /* 1132 * This function is called immediately after a message has 1133 * been serialized 1134 */ 1135 OPENSSL_assert(s->init_off == 0); 1136 1137 frag = dtls1_hm_fragment_new(s->init_num, 0); 1138 if (frag == NULL) 1139 return 0; 1140 1141 memcpy(frag->fragment, s->init_buf->data, s->init_num); 1142 1143 if (is_ccs) { 1144 OPENSSL_assert(s->d1->w_msg_hdr.msg_len + 1145 ((s->version == DTLS1_VERSION) ? 1146 DTLS1_CCS_HEADER_LENGTH : 3) == (unsigned int)s->init_num); 1147 } else { 1148 OPENSSL_assert(s->d1->w_msg_hdr.msg_len + 1149 DTLS1_HM_HEADER_LENGTH == (unsigned int)s->init_num); 1150 } 1151 1152 frag->msg_header.msg_len = s->d1->w_msg_hdr.msg_len; 1153 frag->msg_header.seq = s->d1->w_msg_hdr.seq; 1154 frag->msg_header.type = s->d1->w_msg_hdr.type; 1155 frag->msg_header.frag_off = 0; 1156 frag->msg_header.frag_len = s->d1->w_msg_hdr.msg_len; 1157 frag->msg_header.is_ccs = is_ccs; 1158 1159 /* save current state*/ 1160 frag->msg_header.saved_retransmit_state.enc_write_ctx = s->enc_write_ctx; 1161 frag->msg_header.saved_retransmit_state.write_hash = s->write_hash; 1162 frag->msg_header.saved_retransmit_state.session = s->session; 1163 frag->msg_header.saved_retransmit_state.epoch = s->d1->w_epoch; 1164 1165 memset(seq64be, 0, sizeof(seq64be)); 1166 seq64be[6] = (unsigned char)(dtls1_get_queue_priority( 1167 frag->msg_header.seq, frag->msg_header.is_ccs) >> 8); 1168 seq64be[7] = (unsigned char)(dtls1_get_queue_priority( 1169 frag->msg_header.seq, frag->msg_header.is_ccs)); 1170 1171 item = pitem_new(seq64be, frag); 1172 if (item == NULL) { 1173 dtls1_hm_fragment_free(frag); 1174 return 0; 1175 } 1176 1177 pqueue_insert(s->d1->sent_messages, item); 1178 return 1; 1179 } 1180 1181 int 1182 dtls1_retransmit_message(SSL *s, unsigned short seq, unsigned long frag_off, 1183 int *found) 1184 { 1185 int ret; 1186 /* XDTLS: for now assuming that read/writes are blocking */ 1187 pitem *item; 1188 hm_fragment *frag; 1189 unsigned long header_length; 1190 unsigned char seq64be[8]; 1191 struct dtls1_retransmit_state saved_state; 1192 unsigned char save_write_sequence[8]; 1193 1194 /* 1195 OPENSSL_assert(s->init_num == 0); 1196 OPENSSL_assert(s->init_off == 0); 1197 */ 1198 1199 /* XDTLS: the requested message ought to be found, otherwise error */ 1200 memset(seq64be, 0, sizeof(seq64be)); 1201 seq64be[6] = (unsigned char)(seq >> 8); 1202 seq64be[7] = (unsigned char)seq; 1203 1204 item = pqueue_find(s->d1->sent_messages, seq64be); 1205 if (item == NULL) { 1206 fprintf(stderr, "retransmit: message %d non-existant\n", seq); 1207 *found = 0; 1208 return 0; 1209 } 1210 1211 *found = 1; 1212 frag = (hm_fragment *)item->data; 1213 1214 if (frag->msg_header.is_ccs) 1215 header_length = DTLS1_CCS_HEADER_LENGTH; 1216 else 1217 header_length = DTLS1_HM_HEADER_LENGTH; 1218 1219 memcpy(s->init_buf->data, frag->fragment, 1220 frag->msg_header.msg_len + header_length); 1221 s->init_num = frag->msg_header.msg_len + header_length; 1222 1223 dtls1_set_message_header_int(s, frag->msg_header.type, 1224 frag->msg_header.msg_len, frag->msg_header.seq, 0, 1225 frag->msg_header.frag_len); 1226 1227 /* save current state */ 1228 saved_state.enc_write_ctx = s->enc_write_ctx; 1229 saved_state.write_hash = s->write_hash; 1230 saved_state.session = s->session; 1231 saved_state.epoch = s->d1->w_epoch; 1232 1233 s->d1->retransmitting = 1; 1234 1235 /* restore state in which the message was originally sent */ 1236 s->enc_write_ctx = frag->msg_header.saved_retransmit_state.enc_write_ctx; 1237 s->write_hash = frag->msg_header.saved_retransmit_state.write_hash; 1238 s->session = frag->msg_header.saved_retransmit_state.session; 1239 s->d1->w_epoch = frag->msg_header.saved_retransmit_state.epoch; 1240 1241 if (frag->msg_header.saved_retransmit_state.epoch == 1242 saved_state.epoch - 1) { 1243 memcpy(save_write_sequence, s->s3->write_sequence, 1244 sizeof(s->s3->write_sequence)); 1245 memcpy(s->s3->write_sequence, s->d1->last_write_sequence, 1246 sizeof(s->s3->write_sequence)); 1247 } 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->enc_write_ctx = saved_state.enc_write_ctx; 1254 s->write_hash = saved_state.write_hash; 1255 s->session = saved_state.session; 1256 s->d1->w_epoch = saved_state.epoch; 1257 1258 if (frag->msg_header.saved_retransmit_state.epoch == 1259 saved_state.epoch - 1) { 1260 memcpy(s->d1->last_write_sequence, s->s3->write_sequence, 1261 sizeof(s->s3->write_sequence)); 1262 memcpy(s->s3->write_sequence, save_write_sequence, 1263 sizeof(s->s3->write_sequence)); 1264 } 1265 1266 s->d1->retransmitting = 0; 1267 1268 (void)BIO_flush(SSL_get_wbio(s)); 1269 return ret; 1270 } 1271 1272 /* call this function when the buffered messages are no longer needed */ 1273 void 1274 dtls1_clear_record_buffer(SSL *s) 1275 { 1276 pitem *item; 1277 1278 for(item = pqueue_pop(s->d1->sent_messages); item != NULL; 1279 item = pqueue_pop(s->d1->sent_messages)) { 1280 dtls1_hm_fragment_free((hm_fragment *)item->data); 1281 pitem_free(item); 1282 } 1283 } 1284 1285 unsigned char * 1286 dtls1_set_message_header(SSL *s, unsigned char *p, unsigned char mt, 1287 unsigned long len, unsigned long frag_off, unsigned long frag_len) 1288 { 1289 /* Don't change sequence numbers while listening */ 1290 if (frag_off == 0 && !s->d1->listen) { 1291 s->d1->handshake_write_seq = s->d1->next_handshake_write_seq; 1292 s->d1->next_handshake_write_seq++; 1293 } 1294 1295 dtls1_set_message_header_int(s, mt, len, s->d1->handshake_write_seq, 1296 frag_off, frag_len); 1297 1298 return p += DTLS1_HM_HEADER_LENGTH; 1299 } 1300 1301 /* don't actually do the writing, wait till the MTU has been retrieved */ 1302 static void 1303 dtls1_set_message_header_int(SSL *s, unsigned char mt, unsigned long len, 1304 unsigned short seq_num, unsigned long frag_off, unsigned long frag_len) 1305 { 1306 struct hm_header_st *msg_hdr = &s->d1->w_msg_hdr; 1307 1308 msg_hdr->type = mt; 1309 msg_hdr->msg_len = len; 1310 msg_hdr->seq = seq_num; 1311 msg_hdr->frag_off = frag_off; 1312 msg_hdr->frag_len = frag_len; 1313 } 1314 1315 static void 1316 dtls1_fix_message_header(SSL *s, unsigned long frag_off, unsigned long frag_len) 1317 { 1318 struct hm_header_st *msg_hdr = &s->d1->w_msg_hdr; 1319 1320 msg_hdr->frag_off = frag_off; 1321 msg_hdr->frag_len = frag_len; 1322 } 1323 1324 static unsigned char * 1325 dtls1_write_message_header(SSL *s, unsigned char *p) 1326 { 1327 struct hm_header_st *msg_hdr = &s->d1->w_msg_hdr; 1328 1329 *p++ = msg_hdr->type; 1330 l2n3(msg_hdr->msg_len, p); 1331 1332 s2n(msg_hdr->seq, p); 1333 l2n3(msg_hdr->frag_off, p); 1334 l2n3(msg_hdr->frag_len, p); 1335 1336 return p; 1337 } 1338 1339 unsigned int 1340 dtls1_min_mtu(void) 1341 { 1342 return (g_probable_mtu[(sizeof(g_probable_mtu) / 1343 sizeof(g_probable_mtu[0])) - 1]); 1344 } 1345 1346 static unsigned int 1347 dtls1_guess_mtu(unsigned int curr_mtu) 1348 { 1349 unsigned int i; 1350 1351 if (curr_mtu == 0) 1352 return g_probable_mtu[0]; 1353 1354 for (i = 0; i < sizeof(g_probable_mtu) / sizeof(g_probable_mtu[0]); i++) 1355 if (curr_mtu > g_probable_mtu[i]) 1356 return g_probable_mtu[i]; 1357 1358 return curr_mtu; 1359 } 1360 1361 void 1362 dtls1_get_message_header(unsigned char *data, struct hm_header_st *msg_hdr) 1363 { 1364 memset(msg_hdr, 0x00, sizeof(struct hm_header_st)); 1365 msg_hdr->type = *(data++); 1366 n2l3(data, msg_hdr->msg_len); 1367 1368 n2s(data, msg_hdr->seq); 1369 n2l3(data, msg_hdr->frag_off); 1370 n2l3(data, msg_hdr->frag_len); 1371 } 1372 1373 void 1374 dtls1_get_ccs_header(unsigned char *data, struct ccs_header_st *ccs_hdr) 1375 { 1376 memset(ccs_hdr, 0x00, sizeof(struct ccs_header_st)); 1377 1378 ccs_hdr->type = *(data++); 1379 } 1380 1381 int 1382 dtls1_shutdown(SSL *s) 1383 { 1384 int ret; 1385 1386 #ifndef OPENSSL_NO_SCTP 1387 if (BIO_dgram_is_sctp(SSL_get_wbio(s)) && 1388 !(s->shutdown & SSL_SENT_SHUTDOWN)) { 1389 ret = BIO_dgram_sctp_wait_for_dry(SSL_get_wbio(s)); 1390 if (ret < 0) 1391 return -1; 1392 1393 if (ret == 0) 1394 BIO_ctrl(SSL_get_wbio(s), 1395 BIO_CTRL_DGRAM_SCTP_SAVE_SHUTDOWN, 1, NULL); 1396 } 1397 #endif 1398 ret = ssl3_shutdown(s); 1399 #ifndef OPENSSL_NO_SCTP 1400 BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_SAVE_SHUTDOWN, 0, NULL); 1401 #endif 1402 return ret; 1403 } 1404