d1_both.c revision 296465
1104445Smdodd/* ssl/d1_both.c */ 2104445Smdodd/* 3104445Smdodd * DTLS implementation written by Nagendra Modadugu 4104445Smdodd * (nagendra@cs.stanford.edu) for the OpenSSL project 2005. 5104445Smdodd */ 6104445Smdodd/* ==================================================================== 7104445Smdodd * Copyright (c) 1998-2005 The OpenSSL Project. All rights reserved. 8104445Smdodd * 9104445Smdodd * Redistribution and use in source and binary forms, with or without 10104445Smdodd * modification, are permitted provided that the following conditions 11104445Smdodd * are met: 12104445Smdodd * 13104445Smdodd * 1. Redistributions of source code must retain the above copyright 14104445Smdodd * notice, this list of conditions and the following disclaimer. 15104445Smdodd * 16104445Smdodd * 2. Redistributions in binary form must reproduce the above copyright 17104445Smdodd * notice, this list of conditions and the following disclaimer in 18104445Smdodd * the documentation and/or other materials provided with the 19104445Smdodd * distribution. 20104445Smdodd * 21104445Smdodd * 3. All advertising materials mentioning features or use of this 22104445Smdodd * software must display the following acknowledgment: 23104445Smdodd * "This product includes software developed by the OpenSSL Project 24104545Smdodd * for use in the OpenSSL Toolkit. (http://www.openssl.org/)" 25104445Smdodd * 26104445Smdodd * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to 27104445Smdodd * endorse or promote products derived from this software without 28104445Smdodd * prior written permission. For written permission, please contact 29104445Smdodd * openssl-core@openssl.org. 30104445Smdodd * 31104445Smdodd * 5. Products derived from this software may not be called "OpenSSL" 32104445Smdodd * nor may "OpenSSL" appear in their names without prior written 33104445Smdodd * permission of the OpenSSL Project. 34104445Smdodd * 35104445Smdodd * 6. Redistributions of any form whatsoever must retain the following 36104445Smdodd * acknowledgment: 37104445Smdodd * "This product includes software developed by the OpenSSL Project 38130585Sphk * for use in the OpenSSL Toolkit (http://www.openssl.org/)" 39104445Smdodd * 40104445Smdodd * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY 41104445Smdodd * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 42104445Smdodd * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 43104445Smdodd * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR 44104445Smdodd * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 45104445Smdodd * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 46104445Smdodd * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 47104445Smdodd * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 48104445Smdodd * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, 49104445Smdodd * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 50104445Smdodd * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED 51104445Smdodd * OF THE POSSIBILITY OF SUCH DAMAGE. 52104445Smdodd * ==================================================================== 53104445Smdodd * 54104445Smdodd * This product includes cryptographic software written by Eric Young 55104445Smdodd * (eay@cryptsoft.com). This product includes software written by Tim 56104445Smdodd * Hudson (tjh@cryptsoft.com). 57104445Smdodd * 58104445Smdodd */ 59104445Smdodd/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com) 60104445Smdodd * All rights reserved. 61104445Smdodd * 62104445Smdodd * This package is an SSL implementation written 63104445Smdodd * by Eric Young (eay@cryptsoft.com). 64104445Smdodd * The implementation was written so as to conform with Netscapes SSL. 65104445Smdodd * 66104445Smdodd * This library is free for commercial and non-commercial use as long as 67104445Smdodd * the following conditions are aheared to. The following conditions 68104445Smdodd * apply to all code found in this distribution, be it the RC4, RSA, 69104445Smdodd * lhash, DES, etc., code; not just the SSL code. The SSL documentation 70104445Smdodd * included with this distribution is covered by the same copyright terms 71104445Smdodd * except that the holder is Tim Hudson (tjh@cryptsoft.com). 72104445Smdodd * 73104445Smdodd * Copyright remains Eric Young's, and as such any Copyright notices in 74104445Smdodd * 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#define RSMBLY_BITMASK_SIZE(msg_len) (((msg_len) + 7) / 8) 127 128#define RSMBLY_BITMASK_MARK(bitmask, start, end) { \ 129 if ((end) - (start) <= 8) { \ 130 long ii; \ 131 for (ii = (start); ii < (end); ii++) bitmask[((ii) >> 3)] |= (1 << ((ii) & 7)); \ 132 } else { \ 133 long ii; \ 134 bitmask[((start) >> 3)] |= bitmask_start_values[((start) & 7)]; \ 135 for (ii = (((start) >> 3) + 1); ii < ((((end) - 1)) >> 3); ii++) bitmask[ii] = 0xff; \ 136 bitmask[(((end) - 1) >> 3)] |= bitmask_end_values[((end) & 7)]; \ 137 } } 138 139#define RSMBLY_BITMASK_IS_COMPLETE(bitmask, msg_len, is_complete) { \ 140 long ii; \ 141 OPENSSL_assert((msg_len) > 0); \ 142 is_complete = 1; \ 143 if (bitmask[(((msg_len) - 1) >> 3)] != bitmask_end_values[((msg_len) & 7)]) is_complete = 0; \ 144 if (is_complete) for (ii = (((msg_len) - 1) >> 3) - 1; ii >= 0 ; ii--) \ 145 if (bitmask[ii] != 0xff) { is_complete = 0; break; } } 146 147#if 0 148# define RSMBLY_BITMASK_PRINT(bitmask, msg_len) { \ 149 long ii; \ 150 printf("bitmask: "); for (ii = 0; ii < (msg_len); ii++) \ 151 printf("%d ", (bitmask[ii >> 3] & (1 << (ii & 7))) >> (ii & 7)); \ 152 printf("\n"); } 153#endif 154 155static unsigned char bitmask_start_values[] = 156 { 0xff, 0xfe, 0xfc, 0xf8, 0xf0, 0xe0, 0xc0, 0x80 }; 157static unsigned char bitmask_end_values[] = 158 { 0xff, 0x01, 0x03, 0x07, 0x0f, 0x1f, 0x3f, 0x7f }; 159 160/* XDTLS: figure out the right values */ 161static unsigned int g_probable_mtu[] = { 1500 - 28, 512 - 28, 256 - 28 }; 162 163static unsigned int dtls1_guess_mtu(unsigned int curr_mtu); 164static void dtls1_fix_message_header(SSL *s, unsigned long frag_off, 165 unsigned long frag_len); 166static unsigned char *dtls1_write_message_header(SSL *s, unsigned char *p); 167static void dtls1_set_message_header_int(SSL *s, unsigned char mt, 168 unsigned long len, 169 unsigned short seq_num, 170 unsigned long frag_off, 171 unsigned long frag_len); 172static long dtls1_get_message_fragment(SSL *s, int st1, int stn, long max, 173 int *ok); 174 175static hm_fragment *dtls1_hm_fragment_new(unsigned long frag_len, 176 int reassembly) 177{ 178 hm_fragment *frag = NULL; 179 unsigned char *buf = NULL; 180 unsigned char *bitmask = NULL; 181 182 frag = (hm_fragment *)OPENSSL_malloc(sizeof(hm_fragment)); 183 if (frag == NULL) 184 return NULL; 185 186 if (frag_len) { 187 buf = (unsigned char *)OPENSSL_malloc(frag_len); 188 if (buf == NULL) { 189 OPENSSL_free(frag); 190 return NULL; 191 } 192 } 193 194 /* zero length fragment gets zero frag->fragment */ 195 frag->fragment = buf; 196 197 /* Initialize reassembly bitmask if necessary */ 198 if (reassembly) { 199 bitmask = 200 (unsigned char *)OPENSSL_malloc(RSMBLY_BITMASK_SIZE(frag_len)); 201 if (bitmask == NULL) { 202 if (buf != NULL) 203 OPENSSL_free(buf); 204 OPENSSL_free(frag); 205 return NULL; 206 } 207 memset(bitmask, 0, RSMBLY_BITMASK_SIZE(frag_len)); 208 } 209 210 frag->reassembly = bitmask; 211 212 return frag; 213} 214 215static void dtls1_hm_fragment_free(hm_fragment *frag) 216{ 217 if (frag->fragment) 218 OPENSSL_free(frag->fragment); 219 if (frag->reassembly) 220 OPENSSL_free(frag->reassembly); 221 OPENSSL_free(frag); 222} 223 224/* 225 * send s->init_buf in records of type 'type' (SSL3_RT_HANDSHAKE or 226 * SSL3_RT_CHANGE_CIPHER_SPEC) 227 */ 228int dtls1_do_write(SSL *s, int type) 229{ 230 int ret; 231 int curr_mtu; 232 unsigned int len, frag_off, mac_size, blocksize; 233 234 /* AHA! Figure out the MTU, and stick to the right size */ 235 if (s->d1->mtu < dtls1_min_mtu() 236 && !(SSL_get_options(s) & SSL_OP_NO_QUERY_MTU)) { 237 s->d1->mtu = 238 BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_QUERY_MTU, 0, NULL); 239 240 /* 241 * I've seen the kernel return bogus numbers when it doesn't know 242 * (initial write), so just make sure we have a reasonable number 243 */ 244 if (s->d1->mtu < dtls1_min_mtu()) { 245 s->d1->mtu = 0; 246 s->d1->mtu = dtls1_guess_mtu(s->d1->mtu); 247 BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SET_MTU, 248 s->d1->mtu, NULL); 249 } 250 } 251#if 0 252 mtu = s->d1->mtu; 253 254 fprintf(stderr, "using MTU = %d\n", mtu); 255 256 mtu -= (DTLS1_HM_HEADER_LENGTH + DTLS1_RT_HEADER_LENGTH); 257 258 curr_mtu = mtu - BIO_wpending(SSL_get_wbio(s)); 259 260 if (curr_mtu > 0) 261 mtu = curr_mtu; 262 else if ((ret = BIO_flush(SSL_get_wbio(s))) <= 0) 263 return ret; 264 265 if (BIO_wpending(SSL_get_wbio(s)) + s->init_num >= mtu) { 266 ret = BIO_flush(SSL_get_wbio(s)); 267 if (ret <= 0) 268 return ret; 269 mtu = s->d1->mtu - (DTLS1_HM_HEADER_LENGTH + DTLS1_RT_HEADER_LENGTH); 270 } 271#endif 272 273 OPENSSL_assert(s->d1->mtu >= dtls1_min_mtu()); /* should have something 274 * reasonable now */ 275 276 if (s->init_off == 0 && type == SSL3_RT_HANDSHAKE) 277 OPENSSL_assert(s->init_num == 278 (int)s->d1->w_msg_hdr.msg_len + 279 DTLS1_HM_HEADER_LENGTH); 280 281 if (s->write_hash) 282 mac_size = EVP_MD_size(s->write_hash); 283 else 284 mac_size = 0; 285 286 if (s->enc_write_ctx && 287 (EVP_CIPHER_mode(s->enc_write_ctx->cipher) & EVP_CIPH_CBC_MODE)) 288 blocksize = 2 * EVP_CIPHER_block_size(s->enc_write_ctx->cipher); 289 else 290 blocksize = 0; 291 292 frag_off = 0; 293 while (s->init_num) { 294 curr_mtu = s->d1->mtu - BIO_wpending(SSL_get_wbio(s)) - 295 DTLS1_RT_HEADER_LENGTH - mac_size - blocksize; 296 297 if (curr_mtu <= DTLS1_HM_HEADER_LENGTH) { 298 /* 299 * grr.. we could get an error if MTU picked was wrong 300 */ 301 ret = BIO_flush(SSL_get_wbio(s)); 302 if (ret <= 0) 303 return ret; 304 curr_mtu = s->d1->mtu - DTLS1_RT_HEADER_LENGTH - 305 mac_size - blocksize; 306 } 307 308 if (s->init_num > curr_mtu) 309 len = curr_mtu; 310 else 311 len = s->init_num; 312 313 /* 314 * XDTLS: this function is too long. split out the CCS part 315 */ 316 if (type == SSL3_RT_HANDSHAKE) { 317 if (s->init_off != 0) { 318 OPENSSL_assert(s->init_off > DTLS1_HM_HEADER_LENGTH); 319 s->init_off -= DTLS1_HM_HEADER_LENGTH; 320 s->init_num += DTLS1_HM_HEADER_LENGTH; 321 322 if (s->init_num > curr_mtu) 323 len = curr_mtu; 324 else 325 len = s->init_num; 326 } 327 328 dtls1_fix_message_header(s, frag_off, 329 len - DTLS1_HM_HEADER_LENGTH); 330 331 dtls1_write_message_header(s, 332 (unsigned char *)&s->init_buf-> 333 data[s->init_off]); 334 335 OPENSSL_assert(len >= DTLS1_HM_HEADER_LENGTH); 336 } 337 338 ret = dtls1_write_bytes(s, type, &s->init_buf->data[s->init_off], 339 len); 340 if (ret < 0) { 341 /* 342 * might need to update MTU here, but we don't know which 343 * previous packet caused the failure -- so can't really 344 * retransmit anything. continue as if everything is fine and 345 * wait for an alert to handle the retransmit 346 */ 347 if (BIO_ctrl(SSL_get_wbio(s), 348 BIO_CTRL_DGRAM_MTU_EXCEEDED, 0, NULL) > 0) 349 s->d1->mtu = BIO_ctrl(SSL_get_wbio(s), 350 BIO_CTRL_DGRAM_QUERY_MTU, 0, NULL); 351 else 352 return (-1); 353 } else { 354 355 /* 356 * bad if this assert fails, only part of the handshake message 357 * got sent. but why would this happen? 358 */ 359 OPENSSL_assert(len == (unsigned int)ret); 360 361 if (type == SSL3_RT_HANDSHAKE && !s->d1->retransmitting) { 362 /* 363 * should not be done for 'Hello Request's, but in that case 364 * we'll ignore the result anyway 365 */ 366 unsigned char *p = 367 (unsigned char *)&s->init_buf->data[s->init_off]; 368 const struct hm_header_st *msg_hdr = &s->d1->w_msg_hdr; 369 int xlen; 370 371 if (frag_off == 0 && s->client_version != DTLS1_BAD_VER) { 372 /* 373 * reconstruct message header is if it is being sent in 374 * single fragment 375 */ 376 *p++ = msg_hdr->type; 377 l2n3(msg_hdr->msg_len, p); 378 s2n(msg_hdr->seq, p); 379 l2n3(0, p); 380 l2n3(msg_hdr->msg_len, p); 381 p -= DTLS1_HM_HEADER_LENGTH; 382 xlen = ret; 383 } else { 384 p += DTLS1_HM_HEADER_LENGTH; 385 xlen = ret - DTLS1_HM_HEADER_LENGTH; 386 } 387 388 ssl3_finish_mac(s, p, xlen); 389 } 390 391 if (ret == s->init_num) { 392 if (s->msg_callback) 393 s->msg_callback(1, s->version, type, s->init_buf->data, 394 (size_t)(s->init_off + s->init_num), s, 395 s->msg_callback_arg); 396 397 s->init_off = 0; /* done writing this message */ 398 s->init_num = 0; 399 400 return (1); 401 } 402 s->init_off += ret; 403 s->init_num -= ret; 404 frag_off += (ret -= DTLS1_HM_HEADER_LENGTH); 405 } 406 } 407 return (0); 408} 409 410/* 411 * Obtain handshake message of message type 'mt' (any if mt == -1), maximum 412 * acceptable body length 'max'. Read an entire handshake message. Handshake 413 * messages arrive in fragments. 414 */ 415long dtls1_get_message(SSL *s, int st1, int stn, int mt, long max, int *ok) 416{ 417 int i, al; 418 struct hm_header_st *msg_hdr; 419 unsigned char *p; 420 unsigned long msg_len; 421 422 /* 423 * s3->tmp is used to store messages that are unexpected, caused by the 424 * absence of an optional handshake message 425 */ 426 if (s->s3->tmp.reuse_message) { 427 s->s3->tmp.reuse_message = 0; 428 if ((mt >= 0) && (s->s3->tmp.message_type != mt)) { 429 al = SSL_AD_UNEXPECTED_MESSAGE; 430 SSLerr(SSL_F_DTLS1_GET_MESSAGE, SSL_R_UNEXPECTED_MESSAGE); 431 goto f_err; 432 } 433 *ok = 1; 434 s->init_msg = s->init_buf->data + DTLS1_HM_HEADER_LENGTH; 435 s->init_num = (int)s->s3->tmp.message_size; 436 return s->init_num; 437 } 438 439 msg_hdr = &s->d1->r_msg_hdr; 440 memset(msg_hdr, 0x00, sizeof(struct hm_header_st)); 441 442 again: 443 i = dtls1_get_message_fragment(s, st1, stn, max, ok); 444 if (i == DTLS1_HM_BAD_FRAGMENT || i == DTLS1_HM_FRAGMENT_RETRY) { 445 /* bad fragment received */ 446 goto again; 447 } else if (i <= 0 && !*ok) { 448 return i; 449 } 450 451 p = (unsigned char *)s->init_buf->data; 452 msg_len = msg_hdr->msg_len; 453 454 /* reconstruct message header */ 455 *(p++) = msg_hdr->type; 456 l2n3(msg_len, p); 457 s2n(msg_hdr->seq, p); 458 l2n3(0, p); 459 l2n3(msg_len, p); 460 if (s->version != DTLS1_BAD_VER) { 461 p -= DTLS1_HM_HEADER_LENGTH; 462 msg_len += DTLS1_HM_HEADER_LENGTH; 463 } 464 465 ssl3_finish_mac(s, p, msg_len); 466 if (s->msg_callback) 467 s->msg_callback(0, s->version, SSL3_RT_HANDSHAKE, 468 p, msg_len, s, s->msg_callback_arg); 469 470 memset(msg_hdr, 0x00, sizeof(struct hm_header_st)); 471 472 /* Don't change sequence numbers while listening */ 473 if (!s->d1->listen) 474 s->d1->handshake_read_seq++; 475 476 s->init_msg = s->init_buf->data + DTLS1_HM_HEADER_LENGTH; 477 return s->init_num; 478 479 f_err: 480 ssl3_send_alert(s, SSL3_AL_FATAL, al); 481 *ok = 0; 482 return -1; 483} 484 485static int dtls1_preprocess_fragment(SSL *s, struct hm_header_st *msg_hdr, 486 int max) 487{ 488 size_t frag_off, frag_len, msg_len; 489 490 msg_len = msg_hdr->msg_len; 491 frag_off = msg_hdr->frag_off; 492 frag_len = msg_hdr->frag_len; 493 494 /* sanity checking */ 495 if ((frag_off + frag_len) > msg_len) { 496 SSLerr(SSL_F_DTLS1_PREPROCESS_FRAGMENT, SSL_R_EXCESSIVE_MESSAGE_SIZE); 497 return SSL_AD_ILLEGAL_PARAMETER; 498 } 499 500 if ((frag_off + frag_len) > (unsigned long)max) { 501 SSLerr(SSL_F_DTLS1_PREPROCESS_FRAGMENT, SSL_R_EXCESSIVE_MESSAGE_SIZE); 502 return SSL_AD_ILLEGAL_PARAMETER; 503 } 504 505 if (s->d1->r_msg_hdr.frag_off == 0) { /* first fragment */ 506 /* 507 * msg_len is limited to 2^24, but is effectively checked against max 508 * above 509 */ 510 if (!BUF_MEM_grow_clean 511 (s->init_buf, (int)msg_len + DTLS1_HM_HEADER_LENGTH)) { 512 SSLerr(SSL_F_DTLS1_PREPROCESS_FRAGMENT, ERR_R_BUF_LIB); 513 return SSL_AD_INTERNAL_ERROR; 514 } 515 516 s->s3->tmp.message_size = msg_len; 517 s->d1->r_msg_hdr.msg_len = msg_len; 518 s->s3->tmp.message_type = msg_hdr->type; 519 s->d1->r_msg_hdr.type = msg_hdr->type; 520 s->d1->r_msg_hdr.seq = msg_hdr->seq; 521 } else if (msg_len != s->d1->r_msg_hdr.msg_len) { 522 /* 523 * They must be playing with us! BTW, failure to enforce upper limit 524 * would open possibility for buffer overrun. 525 */ 526 SSLerr(SSL_F_DTLS1_PREPROCESS_FRAGMENT, SSL_R_EXCESSIVE_MESSAGE_SIZE); 527 return SSL_AD_ILLEGAL_PARAMETER; 528 } 529 530 return 0; /* no error */ 531} 532 533static int dtls1_retrieve_buffered_fragment(SSL *s, long max, int *ok) 534{ 535 /*- 536 * (0) check whether the desired fragment is available 537 * if so: 538 * (1) copy over the fragment to s->init_buf->data[] 539 * (2) update s->init_num 540 */ 541 pitem *item; 542 hm_fragment *frag; 543 int al; 544 545 *ok = 0; 546 item = pqueue_peek(s->d1->buffered_messages); 547 if (item == NULL) 548 return 0; 549 550 frag = (hm_fragment *)item->data; 551 552 /* Don't return if reassembly still in progress */ 553 if (frag->reassembly != NULL) 554 return 0; 555 556 if (s->d1->handshake_read_seq == frag->msg_header.seq) { 557 unsigned long frag_len = frag->msg_header.frag_len; 558 pqueue_pop(s->d1->buffered_messages); 559 560 al = dtls1_preprocess_fragment(s, &frag->msg_header, max); 561 562 if (al == 0) { /* no alert */ 563 unsigned char *p = 564 (unsigned char *)s->init_buf->data + DTLS1_HM_HEADER_LENGTH; 565 memcpy(&p[frag->msg_header.frag_off], frag->fragment, 566 frag->msg_header.frag_len); 567 } 568 569 dtls1_hm_fragment_free(frag); 570 pitem_free(item); 571 572 if (al == 0) { 573 *ok = 1; 574 return frag_len; 575 } 576 577 ssl3_send_alert(s, SSL3_AL_FATAL, al); 578 s->init_num = 0; 579 *ok = 0; 580 return -1; 581 } else 582 return 0; 583} 584 585/* 586 * dtls1_max_handshake_message_len returns the maximum number of bytes 587 * permitted in a DTLS handshake message for |s|. The minimum is 16KB, but 588 * may be greater if the maximum certificate list size requires it. 589 */ 590static unsigned long dtls1_max_handshake_message_len(const SSL *s) 591{ 592 unsigned long max_len = 593 DTLS1_HM_HEADER_LENGTH + SSL3_RT_MAX_ENCRYPTED_LENGTH; 594 if (max_len < (unsigned long)s->max_cert_list) 595 return s->max_cert_list; 596 return max_len; 597} 598 599static int 600dtls1_reassemble_fragment(SSL *s, const struct hm_header_st *msg_hdr, int *ok) 601{ 602 hm_fragment *frag = NULL; 603 pitem *item = NULL; 604 int i = -1, is_complete; 605 PQ_64BIT seq64; 606 unsigned long frag_len = msg_hdr->frag_len; 607 608 if ((msg_hdr->frag_off + frag_len) > msg_hdr->msg_len || 609 msg_hdr->msg_len > dtls1_max_handshake_message_len(s)) 610 goto err; 611 612 if (frag_len == 0) 613 return DTLS1_HM_FRAGMENT_RETRY; 614 615 /* Try to find item in queue */ 616 pq_64bit_init(&seq64); 617 pq_64bit_assign_word(&seq64, msg_hdr->seq); 618 item = pqueue_find(s->d1->buffered_messages, seq64); 619 pq_64bit_free(&seq64); 620 621 if (item == NULL) { 622 frag = dtls1_hm_fragment_new(msg_hdr->msg_len, 1); 623 if (frag == NULL) 624 goto err; 625 memcpy(&(frag->msg_header), msg_hdr, sizeof(*msg_hdr)); 626 frag->msg_header.frag_len = frag->msg_header.msg_len; 627 frag->msg_header.frag_off = 0; 628 } else { 629 frag = (hm_fragment *)item->data; 630 if (frag->msg_header.msg_len != msg_hdr->msg_len) { 631 item = NULL; 632 frag = NULL; 633 goto err; 634 } 635 } 636 637 /* 638 * If message is already reassembled, this must be a retransmit and can 639 * be dropped. In this case item != NULL and so frag does not need to be 640 * freed. 641 */ 642 if (frag->reassembly == NULL) { 643 unsigned char devnull[256]; 644 645 while (frag_len) { 646 i = s->method->ssl_read_bytes(s, SSL3_RT_HANDSHAKE, 647 devnull, 648 frag_len > 649 sizeof(devnull) ? sizeof(devnull) : 650 frag_len, 0); 651 if (i <= 0) 652 goto err; 653 frag_len -= i; 654 } 655 return DTLS1_HM_FRAGMENT_RETRY; 656 } 657 658 /* read the body of the fragment (header has already been read */ 659 i = s->method->ssl_read_bytes(s, SSL3_RT_HANDSHAKE, 660 frag->fragment + msg_hdr->frag_off, 661 frag_len, 0); 662 if ((unsigned long)i != frag_len) 663 i = -1; 664 if (i <= 0) 665 goto err; 666 667 RSMBLY_BITMASK_MARK(frag->reassembly, (long)msg_hdr->frag_off, 668 (long)(msg_hdr->frag_off + frag_len)); 669 670 RSMBLY_BITMASK_IS_COMPLETE(frag->reassembly, (long)msg_hdr->msg_len, 671 is_complete); 672 673 if (is_complete) { 674 OPENSSL_free(frag->reassembly); 675 frag->reassembly = NULL; 676 } 677 678 if (item == NULL) { 679 pq_64bit_init(&seq64); 680 pq_64bit_assign_word(&seq64, msg_hdr->seq); 681 item = pitem_new(seq64, frag); 682 pq_64bit_free(&seq64); 683 684 if (item == NULL) { 685 i = -1; 686 goto err; 687 } 688 689 item = pqueue_insert(s->d1->buffered_messages, item); 690 /* 691 * pqueue_insert fails iff a duplicate item is inserted. However, 692 * |item| cannot be a duplicate. If it were, |pqueue_find|, above, 693 * would have returned it and control would never have reached this 694 * branch. 695 */ 696 OPENSSL_assert(item != NULL); 697 } 698 699 return DTLS1_HM_FRAGMENT_RETRY; 700 701 err: 702 if (frag != NULL && item == NULL) 703 dtls1_hm_fragment_free(frag); 704 *ok = 0; 705 return i; 706} 707 708static int 709dtls1_process_out_of_seq_message(SSL *s, const struct hm_header_st *msg_hdr, 710 int *ok) 711{ 712 int i = -1; 713 hm_fragment *frag = NULL; 714 pitem *item = NULL; 715 PQ_64BIT seq64; 716 unsigned long frag_len = msg_hdr->frag_len; 717 718 if ((msg_hdr->frag_off + frag_len) > msg_hdr->msg_len) 719 goto err; 720 721 /* Try to find item in queue, to prevent duplicate entries */ 722 pq_64bit_init(&seq64); 723 pq_64bit_assign_word(&seq64, msg_hdr->seq); 724 item = pqueue_find(s->d1->buffered_messages, seq64); 725 pq_64bit_free(&seq64); 726 727 /* 728 * If we already have an entry and this one is a fragment, don't discard 729 * it and rather try to reassemble it. 730 */ 731 if (item != NULL && frag_len != msg_hdr->msg_len) 732 item = NULL; 733 734 /* 735 * Discard the message if sequence number was already there, is too far 736 * in the future, already in the queue or if we received a FINISHED 737 * before the SERVER_HELLO, which then must be a stale retransmit. 738 */ 739 if (msg_hdr->seq <= s->d1->handshake_read_seq || 740 msg_hdr->seq > s->d1->handshake_read_seq + 10 || item != NULL || 741 (s->d1->handshake_read_seq == 0 && msg_hdr->type == SSL3_MT_FINISHED)) 742 { 743 unsigned char devnull[256]; 744 745 while (frag_len) { 746 i = s->method->ssl_read_bytes(s, SSL3_RT_HANDSHAKE, 747 devnull, 748 frag_len > 749 sizeof(devnull) ? sizeof(devnull) : 750 frag_len, 0); 751 if (i <= 0) 752 goto err; 753 frag_len -= i; 754 } 755 } else { 756 if (frag_len != msg_hdr->msg_len) 757 return dtls1_reassemble_fragment(s, msg_hdr, ok); 758 759 if (frag_len > dtls1_max_handshake_message_len(s)) 760 goto err; 761 762 frag = dtls1_hm_fragment_new(frag_len, 0); 763 if (frag == NULL) 764 goto err; 765 766 memcpy(&(frag->msg_header), msg_hdr, sizeof(*msg_hdr)); 767 768 if (frag_len) { 769 /* 770 * read the body of the fragment (header has already been read) 771 */ 772 i = s->method->ssl_read_bytes(s, SSL3_RT_HANDSHAKE, 773 frag->fragment, frag_len, 0); 774 if ((unsigned long)i != frag_len) 775 i = -1; 776 if (i <= 0) 777 goto err; 778 } 779 780 pq_64bit_init(&seq64); 781 pq_64bit_assign_word(&seq64, msg_hdr->seq); 782 783 item = pitem_new(seq64, frag); 784 pq_64bit_free(&seq64); 785 if (item == NULL) 786 goto err; 787 788 item = pqueue_insert(s->d1->buffered_messages, item); 789 /* 790 * pqueue_insert fails iff a duplicate item is inserted. However, 791 * |item| cannot be a duplicate. If it were, |pqueue_find|, above, 792 * would have returned it. Then, either |frag_len| != 793 * |msg_hdr->msg_len| in which case |item| is set to NULL and it will 794 * have been processed with |dtls1_reassemble_fragment|, above, or 795 * the record will have been discarded. 796 */ 797 OPENSSL_assert(item != NULL); 798 } 799 800 return DTLS1_HM_FRAGMENT_RETRY; 801 802 err: 803 if (frag != NULL && item == NULL) 804 dtls1_hm_fragment_free(frag); 805 *ok = 0; 806 return i; 807} 808 809static long 810dtls1_get_message_fragment(SSL *s, int st1, int stn, long max, int *ok) 811{ 812 unsigned char wire[DTLS1_HM_HEADER_LENGTH]; 813 unsigned long len, frag_off, frag_len; 814 int i, al; 815 struct hm_header_st msg_hdr; 816 817 redo: 818 /* see if we have the required fragment already */ 819 if ((frag_len = dtls1_retrieve_buffered_fragment(s, max, ok)) || *ok) { 820 if (*ok) 821 s->init_num = frag_len; 822 return frag_len; 823 } 824 825 /* read handshake message header */ 826 i = s->method->ssl_read_bytes(s, SSL3_RT_HANDSHAKE, wire, 827 DTLS1_HM_HEADER_LENGTH, 0); 828 if (i <= 0) { /* nbio, or an error */ 829 s->rwstate = SSL_READING; 830 *ok = 0; 831 return i; 832 } 833 /* Handshake fails if message header is incomplete */ 834 if (i != DTLS1_HM_HEADER_LENGTH) { 835 al = SSL_AD_UNEXPECTED_MESSAGE; 836 SSLerr(SSL_F_DTLS1_GET_MESSAGE_FRAGMENT, SSL_R_UNEXPECTED_MESSAGE); 837 goto f_err; 838 } 839 840 /* parse the message fragment header */ 841 dtls1_get_message_header(wire, &msg_hdr); 842 843 /* 844 * if this is a future (or stale) message it gets buffered 845 * (or dropped)--no further processing at this time 846 * While listening, we accept seq 1 (ClientHello with cookie) 847 * although we're still expecting seq 0 (ClientHello) 848 */ 849 if (msg_hdr.seq != s->d1->handshake_read_seq 850 && !(s->d1->listen && msg_hdr.seq == 1)) 851 return dtls1_process_out_of_seq_message(s, &msg_hdr, ok); 852 853 len = msg_hdr.msg_len; 854 frag_off = msg_hdr.frag_off; 855 frag_len = msg_hdr.frag_len; 856 857 if (frag_len && frag_len < len) 858 return dtls1_reassemble_fragment(s, &msg_hdr, ok); 859 860 if (!s->server && s->d1->r_msg_hdr.frag_off == 0 && 861 wire[0] == SSL3_MT_HELLO_REQUEST) { 862 /* 863 * The server may always send 'Hello Request' messages -- we are 864 * doing a handshake anyway now, so ignore them if their format is 865 * correct. Does not count for 'Finished' MAC. 866 */ 867 if (wire[1] == 0 && wire[2] == 0 && wire[3] == 0) { 868 if (s->msg_callback) 869 s->msg_callback(0, s->version, SSL3_RT_HANDSHAKE, 870 wire, DTLS1_HM_HEADER_LENGTH, s, 871 s->msg_callback_arg); 872 873 s->init_num = 0; 874 goto redo; 875 } else { /* Incorrectly formated Hello request */ 876 877 al = SSL_AD_UNEXPECTED_MESSAGE; 878 SSLerr(SSL_F_DTLS1_GET_MESSAGE_FRAGMENT, 879 SSL_R_UNEXPECTED_MESSAGE); 880 goto f_err; 881 } 882 } 883 884 if ((al = dtls1_preprocess_fragment(s, &msg_hdr, max))) 885 goto f_err; 886 887 /* XDTLS: ressurect this when restart is in place */ 888 s->state = stn; 889 890 if (frag_len > 0) { 891 unsigned char *p = 892 (unsigned char *)s->init_buf->data + DTLS1_HM_HEADER_LENGTH; 893 894 i = s->method->ssl_read_bytes(s, SSL3_RT_HANDSHAKE, 895 &p[frag_off], frag_len, 0); 896 /* 897 * XDTLS: fix this--message fragments cannot span multiple packets 898 */ 899 if (i <= 0) { 900 s->rwstate = SSL_READING; 901 *ok = 0; 902 return i; 903 } 904 } else 905 i = 0; 906 907 /* 908 * XDTLS: an incorrectly formatted fragment should cause the handshake 909 * to fail 910 */ 911 if (i != (int)frag_len) { 912 al = SSL3_AD_ILLEGAL_PARAMETER; 913 SSLerr(SSL_F_DTLS1_GET_MESSAGE_FRAGMENT, SSL3_AD_ILLEGAL_PARAMETER); 914 goto f_err; 915 } 916 917 *ok = 1; 918 919 /* 920 * Note that s->init_num is *not* used as current offset in 921 * s->init_buf->data, but as a counter summing up fragments' lengths: as 922 * soon as they sum up to handshake packet length, we assume we have got 923 * all the fragments. 924 */ 925 s->init_num = frag_len; 926 return frag_len; 927 928 f_err: 929 ssl3_send_alert(s, SSL3_AL_FATAL, al); 930 s->init_num = 0; 931 932 *ok = 0; 933 return (-1); 934} 935 936int dtls1_send_finished(SSL *s, int a, int b, const char *sender, int slen) 937{ 938 unsigned char *p, *d; 939 int i; 940 unsigned long l; 941 942 if (s->state == a) { 943 d = (unsigned char *)s->init_buf->data; 944 p = &(d[DTLS1_HM_HEADER_LENGTH]); 945 946 i = s->method->ssl3_enc->final_finish_mac(s, 947 &(s->s3->finish_dgst1), 948 &(s->s3->finish_dgst2), 949 sender, slen, 950 s->s3->tmp.finish_md); 951 s->s3->tmp.finish_md_len = i; 952 memcpy(p, s->s3->tmp.finish_md, i); 953 p += i; 954 l = i; 955 956 /* 957 * Copy the finished so we can use it for renegotiation checks 958 */ 959 if (s->type == SSL_ST_CONNECT) { 960 OPENSSL_assert(i <= EVP_MAX_MD_SIZE); 961 memcpy(s->s3->previous_client_finished, s->s3->tmp.finish_md, i); 962 s->s3->previous_client_finished_len = i; 963 } else { 964 OPENSSL_assert(i <= EVP_MAX_MD_SIZE); 965 memcpy(s->s3->previous_server_finished, s->s3->tmp.finish_md, i); 966 s->s3->previous_server_finished_len = i; 967 } 968 969#ifdef OPENSSL_SYS_WIN16 970 /* 971 * MSVC 1.5 does not clear the top bytes of the word unless I do 972 * this. 973 */ 974 l &= 0xffff; 975#endif 976 977 d = dtls1_set_message_header(s, d, SSL3_MT_FINISHED, l, 0, l); 978 s->init_num = (int)l + DTLS1_HM_HEADER_LENGTH; 979 s->init_off = 0; 980 981 /* buffer the message to handle re-xmits */ 982 dtls1_buffer_message(s, 0); 983 984 s->state = b; 985 } 986 987 /* SSL3_ST_SEND_xxxxxx_HELLO_B */ 988 return (dtls1_do_write(s, SSL3_RT_HANDSHAKE)); 989} 990 991/*- 992 * for these 2 messages, we need to 993 * ssl->enc_read_ctx re-init 994 * ssl->s3->read_sequence zero 995 * ssl->s3->read_mac_secret re-init 996 * ssl->session->read_sym_enc assign 997 * ssl->session->read_compression assign 998 * ssl->session->read_hash assign 999 */ 1000int dtls1_send_change_cipher_spec(SSL *s, int a, int b) 1001{ 1002 unsigned char *p; 1003 1004 if (s->state == a) { 1005 p = (unsigned char *)s->init_buf->data; 1006 *p++ = SSL3_MT_CCS; 1007 s->d1->handshake_write_seq = s->d1->next_handshake_write_seq; 1008 s->init_num = DTLS1_CCS_HEADER_LENGTH; 1009 1010 if (s->client_version == DTLS1_BAD_VER) { 1011 s->d1->next_handshake_write_seq++; 1012 s2n(s->d1->handshake_write_seq, p); 1013 s->init_num += 2; 1014 } 1015 1016 s->init_off = 0; 1017 1018 dtls1_set_message_header_int(s, SSL3_MT_CCS, 0, 1019 s->d1->handshake_write_seq, 0, 0); 1020 1021 /* buffer the message to handle re-xmits */ 1022 dtls1_buffer_message(s, 1); 1023 1024 s->state = b; 1025 } 1026 1027 /* SSL3_ST_CW_CHANGE_B */ 1028 return (dtls1_do_write(s, SSL3_RT_CHANGE_CIPHER_SPEC)); 1029} 1030 1031static int dtls1_add_cert_to_buf(BUF_MEM *buf, unsigned long *l, X509 *x) 1032{ 1033 int n; 1034 unsigned char *p; 1035 1036 n = i2d_X509(x, NULL); 1037 if (!BUF_MEM_grow_clean(buf, (int)(n + (*l) + 3))) { 1038 SSLerr(SSL_F_DTLS1_ADD_CERT_TO_BUF, ERR_R_BUF_LIB); 1039 return 0; 1040 } 1041 p = (unsigned char *)&(buf->data[*l]); 1042 l2n3(n, p); 1043 i2d_X509(x, &p); 1044 *l += n + 3; 1045 1046 return 1; 1047} 1048 1049unsigned long dtls1_output_cert_chain(SSL *s, X509 *x) 1050{ 1051 unsigned char *p; 1052 int i; 1053 unsigned long l = 3 + DTLS1_HM_HEADER_LENGTH; 1054 BUF_MEM *buf; 1055 1056 /* TLSv1 sends a chain with nothing in it, instead of an alert */ 1057 buf = s->init_buf; 1058 if (!BUF_MEM_grow_clean(buf, 10)) { 1059 SSLerr(SSL_F_DTLS1_OUTPUT_CERT_CHAIN, ERR_R_BUF_LIB); 1060 return (0); 1061 } 1062 if (x != NULL) { 1063 X509_STORE_CTX xs_ctx; 1064 1065 if (!X509_STORE_CTX_init(&xs_ctx, s->ctx->cert_store, x, NULL)) { 1066 SSLerr(SSL_F_DTLS1_OUTPUT_CERT_CHAIN, ERR_R_X509_LIB); 1067 return (0); 1068 } 1069 1070 X509_verify_cert(&xs_ctx); 1071 /* Don't leave errors in the queue */ 1072 ERR_clear_error(); 1073 for (i = 0; i < sk_X509_num(xs_ctx.chain); i++) { 1074 x = sk_X509_value(xs_ctx.chain, i); 1075 1076 if (!dtls1_add_cert_to_buf(buf, &l, x)) { 1077 X509_STORE_CTX_cleanup(&xs_ctx); 1078 return 0; 1079 } 1080 } 1081 X509_STORE_CTX_cleanup(&xs_ctx); 1082 } 1083 /* Thawte special :-) */ 1084 for (i = 0; i < sk_X509_num(s->ctx->extra_certs); i++) { 1085 x = sk_X509_value(s->ctx->extra_certs, i); 1086 if (!dtls1_add_cert_to_buf(buf, &l, x)) 1087 return 0; 1088 } 1089 1090 l -= (3 + DTLS1_HM_HEADER_LENGTH); 1091 1092 p = (unsigned char *)&(buf->data[DTLS1_HM_HEADER_LENGTH]); 1093 l2n3(l, p); 1094 l += 3; 1095 p = (unsigned char *)&(buf->data[0]); 1096 p = dtls1_set_message_header(s, p, SSL3_MT_CERTIFICATE, l, 0, l); 1097 1098 l += DTLS1_HM_HEADER_LENGTH; 1099 return (l); 1100} 1101 1102int dtls1_read_failed(SSL *s, int code) 1103{ 1104 if (code > 0) { 1105 fprintf(stderr, "invalid state reached %s:%d", __FILE__, __LINE__); 1106 return 1; 1107 } 1108 1109 if (!dtls1_is_timer_expired(s)) { 1110 /* 1111 * not a timeout, none of our business, let higher layers handle 1112 * this. in fact it's probably an error 1113 */ 1114 return code; 1115 } 1116 1117 /* done, no need to send a retransmit */ 1118 if (!SSL_in_init(s)) { 1119 BIO_set_flags(SSL_get_rbio(s), BIO_FLAGS_READ); 1120 return code; 1121 } 1122#if 0 /* for now, each alert contains only one 1123 * record number */ 1124 item = pqueue_peek(state->rcvd_records); 1125 if (item) { 1126 /* send an alert immediately for all the missing records */ 1127 } else 1128#endif 1129 1130#if 0 /* no more alert sending, just retransmit the 1131 * last set of messages */ 1132 if (state->timeout.read_timeouts >= DTLS1_TMO_READ_COUNT) 1133 ssl3_send_alert(s, SSL3_AL_WARNING, 1134 DTLS1_AD_MISSING_HANDSHAKE_MESSAGE); 1135#endif 1136 1137 return dtls1_handle_timeout(s); 1138} 1139 1140int dtls1_get_queue_priority(unsigned short seq, int is_ccs) 1141{ 1142 /* 1143 * The index of the retransmission queue actually is the message sequence 1144 * number, since the queue only contains messages of a single handshake. 1145 * However, the ChangeCipherSpec has no message sequence number and so 1146 * using only the sequence will result in the CCS and Finished having the 1147 * same index. To prevent this, the sequence number is multiplied by 2. 1148 * In case of a CCS 1 is subtracted. This does not only differ CSS and 1149 * Finished, it also maintains the order of the index (important for 1150 * priority queues) and fits in the unsigned short variable. 1151 */ 1152 return seq * 2 - is_ccs; 1153} 1154 1155int dtls1_retransmit_buffered_messages(SSL *s) 1156{ 1157 pqueue sent = s->d1->sent_messages; 1158 piterator iter; 1159 pitem *item; 1160 hm_fragment *frag; 1161 int found = 0; 1162 1163 iter = pqueue_iterator(sent); 1164 1165 for (item = pqueue_next(&iter); item != NULL; item = pqueue_next(&iter)) { 1166 frag = (hm_fragment *)item->data; 1167 if (dtls1_retransmit_message(s, (unsigned short) 1168 dtls1_get_queue_priority 1169 (frag->msg_header.seq, 1170 frag->msg_header.is_ccs), 0, 1171 &found) <= 0 && found) { 1172 fprintf(stderr, "dtls1_retransmit_message() failed\n"); 1173 return -1; 1174 } 1175 } 1176 1177 return 1; 1178} 1179 1180int dtls1_buffer_message(SSL *s, int is_ccs) 1181{ 1182 pitem *item; 1183 hm_fragment *frag; 1184 PQ_64BIT seq64; 1185 1186 /* 1187 * this function is called immediately after a message has been 1188 * serialized 1189 */ 1190 OPENSSL_assert(s->init_off == 0); 1191 1192 frag = dtls1_hm_fragment_new(s->init_num, 0); 1193 if (!frag) 1194 return 0; 1195 1196 memcpy(frag->fragment, s->init_buf->data, s->init_num); 1197 1198 if (is_ccs) { 1199 OPENSSL_assert(s->d1->w_msg_hdr.msg_len + 1200 DTLS1_CCS_HEADER_LENGTH <= (unsigned int)s->init_num); 1201 } else { 1202 OPENSSL_assert(s->d1->w_msg_hdr.msg_len + 1203 DTLS1_HM_HEADER_LENGTH == (unsigned int)s->init_num); 1204 } 1205 1206 frag->msg_header.msg_len = s->d1->w_msg_hdr.msg_len; 1207 frag->msg_header.seq = s->d1->w_msg_hdr.seq; 1208 frag->msg_header.type = s->d1->w_msg_hdr.type; 1209 frag->msg_header.frag_off = 0; 1210 frag->msg_header.frag_len = s->d1->w_msg_hdr.msg_len; 1211 frag->msg_header.is_ccs = is_ccs; 1212 1213 /* save current state */ 1214 frag->msg_header.saved_retransmit_state.enc_write_ctx = s->enc_write_ctx; 1215 frag->msg_header.saved_retransmit_state.write_hash = s->write_hash; 1216 frag->msg_header.saved_retransmit_state.compress = s->compress; 1217 frag->msg_header.saved_retransmit_state.session = s->session; 1218 frag->msg_header.saved_retransmit_state.epoch = s->d1->w_epoch; 1219 1220 pq_64bit_init(&seq64); 1221 1222 pq_64bit_assign_word(&seq64, 1223 dtls1_get_queue_priority(frag->msg_header.seq, 1224 frag->msg_header.is_ccs)); 1225 1226 item = pitem_new(seq64, frag); 1227 pq_64bit_free(&seq64); 1228 if (item == NULL) { 1229 dtls1_hm_fragment_free(frag); 1230 return 0; 1231 } 1232#if 0 1233 fprintf(stderr, "buffered messge: \ttype = %xx\n", msg_buf->type); 1234 fprintf(stderr, "\t\t\t\t\tlen = %d\n", msg_buf->len); 1235 fprintf(stderr, "\t\t\t\t\tseq_num = %d\n", msg_buf->seq_num); 1236#endif 1237 1238 pqueue_insert(s->d1->sent_messages, item); 1239 return 1; 1240} 1241 1242int 1243dtls1_retransmit_message(SSL *s, unsigned short seq, unsigned long frag_off, 1244 int *found) 1245{ 1246 int ret; 1247 /* XDTLS: for now assuming that read/writes are blocking */ 1248 pitem *item; 1249 hm_fragment *frag; 1250 unsigned long header_length; 1251 PQ_64BIT seq64; 1252 struct dtls1_retransmit_state saved_state; 1253 unsigned char save_write_sequence[8]; 1254 1255 /*- 1256 OPENSSL_assert(s->init_num == 0); 1257 OPENSSL_assert(s->init_off == 0); 1258 */ 1259 1260 /* XDTLS: the requested message ought to be found, otherwise error */ 1261 pq_64bit_init(&seq64); 1262 pq_64bit_assign_word(&seq64, seq); 1263 1264 item = pqueue_find(s->d1->sent_messages, seq64); 1265 pq_64bit_free(&seq64); 1266 if (item == NULL) { 1267 fprintf(stderr, "retransmit: message %d non-existant\n", seq); 1268 *found = 0; 1269 return 0; 1270 } 1271 1272 *found = 1; 1273 frag = (hm_fragment *)item->data; 1274 1275 if (frag->msg_header.is_ccs) 1276 header_length = DTLS1_CCS_HEADER_LENGTH; 1277 else 1278 header_length = DTLS1_HM_HEADER_LENGTH; 1279 1280 memcpy(s->init_buf->data, frag->fragment, 1281 frag->msg_header.msg_len + header_length); 1282 s->init_num = frag->msg_header.msg_len + header_length; 1283 1284 dtls1_set_message_header_int(s, frag->msg_header.type, 1285 frag->msg_header.msg_len, 1286 frag->msg_header.seq, 0, 1287 frag->msg_header.frag_len); 1288 1289 /* save current state */ 1290 saved_state.enc_write_ctx = s->enc_write_ctx; 1291 saved_state.write_hash = s->write_hash; 1292 saved_state.compress = s->compress; 1293 saved_state.session = s->session; 1294 saved_state.epoch = s->d1->w_epoch; 1295 saved_state.epoch = s->d1->w_epoch; 1296 1297 s->d1->retransmitting = 1; 1298 1299 /* restore state in which the message was originally sent */ 1300 s->enc_write_ctx = frag->msg_header.saved_retransmit_state.enc_write_ctx; 1301 s->write_hash = frag->msg_header.saved_retransmit_state.write_hash; 1302 s->compress = frag->msg_header.saved_retransmit_state.compress; 1303 s->session = frag->msg_header.saved_retransmit_state.session; 1304 s->d1->w_epoch = frag->msg_header.saved_retransmit_state.epoch; 1305 1306 if (frag->msg_header.saved_retransmit_state.epoch == 1307 saved_state.epoch - 1) { 1308 memcpy(save_write_sequence, s->s3->write_sequence, 1309 sizeof(s->s3->write_sequence)); 1310 memcpy(s->s3->write_sequence, s->d1->last_write_sequence, 1311 sizeof(s->s3->write_sequence)); 1312 } 1313 1314 ret = dtls1_do_write(s, frag->msg_header.is_ccs ? 1315 SSL3_RT_CHANGE_CIPHER_SPEC : SSL3_RT_HANDSHAKE); 1316 1317 /* restore current state */ 1318 s->enc_write_ctx = saved_state.enc_write_ctx; 1319 s->write_hash = saved_state.write_hash; 1320 s->compress = saved_state.compress; 1321 s->session = saved_state.session; 1322 s->d1->w_epoch = saved_state.epoch; 1323 1324 if (frag->msg_header.saved_retransmit_state.epoch == 1325 saved_state.epoch - 1) { 1326 memcpy(s->d1->last_write_sequence, s->s3->write_sequence, 1327 sizeof(s->s3->write_sequence)); 1328 memcpy(s->s3->write_sequence, save_write_sequence, 1329 sizeof(s->s3->write_sequence)); 1330 } 1331 1332 s->d1->retransmitting = 0; 1333 1334 (void)BIO_flush(SSL_get_wbio(s)); 1335 return ret; 1336} 1337 1338/* call this function when the buffered messages are no longer needed */ 1339void dtls1_clear_record_buffer(SSL *s) 1340{ 1341 pitem *item; 1342 1343 for (item = pqueue_pop(s->d1->sent_messages); 1344 item != NULL; item = pqueue_pop(s->d1->sent_messages)) { 1345 dtls1_hm_fragment_free((hm_fragment *)item->data); 1346 pitem_free(item); 1347 } 1348} 1349 1350unsigned char *dtls1_set_message_header(SSL *s, unsigned char *p, 1351 unsigned char mt, unsigned long len, 1352 unsigned long frag_off, 1353 unsigned long frag_len) 1354{ 1355 /* Don't change sequence numbers while listening */ 1356 if (frag_off == 0 && !s->d1->listen) { 1357 s->d1->handshake_write_seq = s->d1->next_handshake_write_seq; 1358 s->d1->next_handshake_write_seq++; 1359 } 1360 1361 dtls1_set_message_header_int(s, mt, len, s->d1->handshake_write_seq, 1362 frag_off, frag_len); 1363 1364 return p += DTLS1_HM_HEADER_LENGTH; 1365} 1366 1367/* don't actually do the writing, wait till the MTU has been retrieved */ 1368static void 1369dtls1_set_message_header_int(SSL *s, unsigned char mt, 1370 unsigned long len, unsigned short seq_num, 1371 unsigned long frag_off, unsigned long frag_len) 1372{ 1373 struct hm_header_st *msg_hdr = &s->d1->w_msg_hdr; 1374 1375 msg_hdr->type = mt; 1376 msg_hdr->msg_len = len; 1377 msg_hdr->seq = seq_num; 1378 msg_hdr->frag_off = frag_off; 1379 msg_hdr->frag_len = frag_len; 1380} 1381 1382static void 1383dtls1_fix_message_header(SSL *s, unsigned long frag_off, 1384 unsigned long frag_len) 1385{ 1386 struct hm_header_st *msg_hdr = &s->d1->w_msg_hdr; 1387 1388 msg_hdr->frag_off = frag_off; 1389 msg_hdr->frag_len = frag_len; 1390} 1391 1392static unsigned char *dtls1_write_message_header(SSL *s, unsigned char *p) 1393{ 1394 struct hm_header_st *msg_hdr = &s->d1->w_msg_hdr; 1395 1396 *p++ = msg_hdr->type; 1397 l2n3(msg_hdr->msg_len, p); 1398 1399 s2n(msg_hdr->seq, p); 1400 l2n3(msg_hdr->frag_off, p); 1401 l2n3(msg_hdr->frag_len, p); 1402 1403 return p; 1404} 1405 1406unsigned int dtls1_min_mtu(void) 1407{ 1408 return (g_probable_mtu[(sizeof(g_probable_mtu) / 1409 sizeof(g_probable_mtu[0])) - 1]); 1410} 1411 1412static unsigned int dtls1_guess_mtu(unsigned int curr_mtu) 1413{ 1414 size_t i; 1415 1416 if (curr_mtu == 0) 1417 return g_probable_mtu[0]; 1418 1419 for (i = 0; i < sizeof(g_probable_mtu) / sizeof(g_probable_mtu[0]); i++) 1420 if (curr_mtu > g_probable_mtu[i]) 1421 return g_probable_mtu[i]; 1422 1423 return curr_mtu; 1424} 1425 1426void 1427dtls1_get_message_header(unsigned char *data, struct hm_header_st *msg_hdr) 1428{ 1429 memset(msg_hdr, 0x00, sizeof(struct hm_header_st)); 1430 msg_hdr->type = *(data++); 1431 n2l3(data, msg_hdr->msg_len); 1432 1433 n2s(data, msg_hdr->seq); 1434 n2l3(data, msg_hdr->frag_off); 1435 n2l3(data, msg_hdr->frag_len); 1436} 1437 1438void dtls1_get_ccs_header(unsigned char *data, struct ccs_header_st *ccs_hdr) 1439{ 1440 memset(ccs_hdr, 0x00, sizeof(struct ccs_header_st)); 1441 1442 ccs_hdr->type = *(data++); 1443} 1444