rec_layer_d1.c revision 1.1.1.5
1/* 2 * Copyright 2005-2018 The OpenSSL Project Authors. All Rights Reserved. 3 * 4 * Licensed under the OpenSSL license (the "License"). You may not use 5 * this file except in compliance with the License. You can obtain a copy 6 * in the file LICENSE in the source distribution or at 7 * https://www.openssl.org/source/license.html 8 */ 9 10#include <stdio.h> 11#include <errno.h> 12#include "../ssl_locl.h" 13#include <openssl/evp.h> 14#include <openssl/buffer.h> 15#include "record_locl.h" 16#include "../packet_locl.h" 17#include "internal/cryptlib.h" 18 19int DTLS_RECORD_LAYER_new(RECORD_LAYER *rl) 20{ 21 DTLS_RECORD_LAYER *d; 22 23 if ((d = OPENSSL_malloc(sizeof(*d))) == NULL) { 24 SSLerr(SSL_F_DTLS_RECORD_LAYER_NEW, ERR_R_MALLOC_FAILURE); 25 return 0; 26 } 27 28 rl->d = d; 29 30 d->unprocessed_rcds.q = pqueue_new(); 31 d->processed_rcds.q = pqueue_new(); 32 d->buffered_app_data.q = pqueue_new(); 33 34 if (d->unprocessed_rcds.q == NULL || d->processed_rcds.q == NULL 35 || d->buffered_app_data.q == NULL) { 36 pqueue_free(d->unprocessed_rcds.q); 37 pqueue_free(d->processed_rcds.q); 38 pqueue_free(d->buffered_app_data.q); 39 OPENSSL_free(d); 40 rl->d = NULL; 41 return 0; 42 } 43 44 return 1; 45} 46 47void DTLS_RECORD_LAYER_free(RECORD_LAYER *rl) 48{ 49 DTLS_RECORD_LAYER_clear(rl); 50 pqueue_free(rl->d->unprocessed_rcds.q); 51 pqueue_free(rl->d->processed_rcds.q); 52 pqueue_free(rl->d->buffered_app_data.q); 53 OPENSSL_free(rl->d); 54 rl->d = NULL; 55} 56 57void DTLS_RECORD_LAYER_clear(RECORD_LAYER *rl) 58{ 59 DTLS_RECORD_LAYER *d; 60 pitem *item = NULL; 61 DTLS1_RECORD_DATA *rdata; 62 pqueue *unprocessed_rcds; 63 pqueue *processed_rcds; 64 pqueue *buffered_app_data; 65 66 d = rl->d; 67 68 while ((item = pqueue_pop(d->unprocessed_rcds.q)) != NULL) { 69 rdata = (DTLS1_RECORD_DATA *)item->data; 70 OPENSSL_free(rdata->rbuf.buf); 71 OPENSSL_free(item->data); 72 pitem_free(item); 73 } 74 75 while ((item = pqueue_pop(d->processed_rcds.q)) != NULL) { 76 rdata = (DTLS1_RECORD_DATA *)item->data; 77 OPENSSL_free(rdata->rbuf.buf); 78 OPENSSL_free(item->data); 79 pitem_free(item); 80 } 81 82 while ((item = pqueue_pop(d->buffered_app_data.q)) != NULL) { 83 rdata = (DTLS1_RECORD_DATA *)item->data; 84 OPENSSL_free(rdata->rbuf.buf); 85 OPENSSL_free(item->data); 86 pitem_free(item); 87 } 88 89 unprocessed_rcds = d->unprocessed_rcds.q; 90 processed_rcds = d->processed_rcds.q; 91 buffered_app_data = d->buffered_app_data.q; 92 memset(d, 0, sizeof(*d)); 93 d->unprocessed_rcds.q = unprocessed_rcds; 94 d->processed_rcds.q = processed_rcds; 95 d->buffered_app_data.q = buffered_app_data; 96} 97 98void DTLS_RECORD_LAYER_set_saved_w_epoch(RECORD_LAYER *rl, unsigned short e) 99{ 100 if (e == rl->d->w_epoch - 1) { 101 memcpy(rl->d->curr_write_sequence, 102 rl->write_sequence, sizeof(rl->write_sequence)); 103 memcpy(rl->write_sequence, 104 rl->d->last_write_sequence, sizeof(rl->write_sequence)); 105 } else if (e == rl->d->w_epoch + 1) { 106 memcpy(rl->d->last_write_sequence, 107 rl->write_sequence, sizeof(unsigned char[8])); 108 memcpy(rl->write_sequence, 109 rl->d->curr_write_sequence, sizeof(rl->write_sequence)); 110 } 111 rl->d->w_epoch = e; 112} 113 114void DTLS_RECORD_LAYER_set_write_sequence(RECORD_LAYER *rl, unsigned char *seq) 115{ 116 memcpy(rl->write_sequence, seq, SEQ_NUM_SIZE); 117} 118 119/* copy buffered record into SSL structure */ 120static int dtls1_copy_record(SSL *s, pitem *item) 121{ 122 DTLS1_RECORD_DATA *rdata; 123 124 rdata = (DTLS1_RECORD_DATA *)item->data; 125 126 SSL3_BUFFER_release(&s->rlayer.rbuf); 127 128 s->rlayer.packet = rdata->packet; 129 s->rlayer.packet_length = rdata->packet_length; 130 memcpy(&s->rlayer.rbuf, &(rdata->rbuf), sizeof(SSL3_BUFFER)); 131 memcpy(&s->rlayer.rrec, &(rdata->rrec), sizeof(SSL3_RECORD)); 132 133 /* Set proper sequence number for mac calculation */ 134 memcpy(&(s->rlayer.read_sequence[2]), &(rdata->packet[5]), 6); 135 136 return 1; 137} 138 139int dtls1_buffer_record(SSL *s, record_pqueue *queue, unsigned char *priority) 140{ 141 DTLS1_RECORD_DATA *rdata; 142 pitem *item; 143 144 /* Limit the size of the queue to prevent DOS attacks */ 145 if (pqueue_size(queue->q) >= 100) 146 return 0; 147 148 rdata = OPENSSL_malloc(sizeof(*rdata)); 149 item = pitem_new(priority, rdata); 150 if (rdata == NULL || item == NULL) { 151 OPENSSL_free(rdata); 152 pitem_free(item); 153 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_DTLS1_BUFFER_RECORD, 154 ERR_R_INTERNAL_ERROR); 155 return -1; 156 } 157 158 rdata->packet = s->rlayer.packet; 159 rdata->packet_length = s->rlayer.packet_length; 160 memcpy(&(rdata->rbuf), &s->rlayer.rbuf, sizeof(SSL3_BUFFER)); 161 memcpy(&(rdata->rrec), &s->rlayer.rrec, sizeof(SSL3_RECORD)); 162 163 item->data = rdata; 164 165#ifndef OPENSSL_NO_SCTP 166 /* Store bio_dgram_sctp_rcvinfo struct */ 167 if (BIO_dgram_is_sctp(SSL_get_rbio(s)) && 168 (SSL_get_state(s) == TLS_ST_SR_FINISHED 169 || SSL_get_state(s) == TLS_ST_CR_FINISHED)) { 170 BIO_ctrl(SSL_get_rbio(s), BIO_CTRL_DGRAM_SCTP_GET_RCVINFO, 171 sizeof(rdata->recordinfo), &rdata->recordinfo); 172 } 173#endif 174 175 s->rlayer.packet = NULL; 176 s->rlayer.packet_length = 0; 177 memset(&s->rlayer.rbuf, 0, sizeof(s->rlayer.rbuf)); 178 memset(&s->rlayer.rrec, 0, sizeof(s->rlayer.rrec)); 179 180 if (!ssl3_setup_buffers(s)) { 181 /* SSLfatal() already called */ 182 OPENSSL_free(rdata->rbuf.buf); 183 OPENSSL_free(rdata); 184 pitem_free(item); 185 return -1; 186 } 187 188 if (pqueue_insert(queue->q, item) == NULL) { 189 /* Must be a duplicate so ignore it */ 190 OPENSSL_free(rdata->rbuf.buf); 191 OPENSSL_free(rdata); 192 pitem_free(item); 193 } 194 195 return 1; 196} 197 198int dtls1_retrieve_buffered_record(SSL *s, record_pqueue *queue) 199{ 200 pitem *item; 201 202 item = pqueue_pop(queue->q); 203 if (item) { 204 dtls1_copy_record(s, item); 205 206 OPENSSL_free(item->data); 207 pitem_free(item); 208 209 return 1; 210 } 211 212 return 0; 213} 214 215/* 216 * retrieve a buffered record that belongs to the new epoch, i.e., not 217 * processed yet 218 */ 219#define dtls1_get_unprocessed_record(s) \ 220 dtls1_retrieve_buffered_record((s), \ 221 &((s)->rlayer.d->unprocessed_rcds)) 222 223int dtls1_process_buffered_records(SSL *s) 224{ 225 pitem *item; 226 SSL3_BUFFER *rb; 227 SSL3_RECORD *rr; 228 DTLS1_BITMAP *bitmap; 229 unsigned int is_next_epoch; 230 int replayok = 1; 231 232 item = pqueue_peek(s->rlayer.d->unprocessed_rcds.q); 233 if (item) { 234 /* Check if epoch is current. */ 235 if (s->rlayer.d->unprocessed_rcds.epoch != s->rlayer.d->r_epoch) 236 return 1; /* Nothing to do. */ 237 238 rr = RECORD_LAYER_get_rrec(&s->rlayer); 239 240 rb = RECORD_LAYER_get_rbuf(&s->rlayer); 241 242 if (SSL3_BUFFER_get_left(rb) > 0) { 243 /* 244 * We've still got data from the current packet to read. There could 245 * be a record from the new epoch in it - so don't overwrite it 246 * with the unprocessed records yet (we'll do it when we've 247 * finished reading the current packet). 248 */ 249 return 1; 250 } 251 252 /* Process all the records. */ 253 while (pqueue_peek(s->rlayer.d->unprocessed_rcds.q)) { 254 dtls1_get_unprocessed_record(s); 255 bitmap = dtls1_get_bitmap(s, rr, &is_next_epoch); 256 if (bitmap == NULL) { 257 /* 258 * Should not happen. This will only ever be NULL when the 259 * current record is from a different epoch. But that cannot 260 * be the case because we already checked the epoch above 261 */ 262 SSLfatal(s, SSL_AD_INTERNAL_ERROR, 263 SSL_F_DTLS1_PROCESS_BUFFERED_RECORDS, 264 ERR_R_INTERNAL_ERROR); 265 return 0; 266 } 267#ifndef OPENSSL_NO_SCTP 268 /* Only do replay check if no SCTP bio */ 269 if (!BIO_dgram_is_sctp(SSL_get_rbio(s))) 270#endif 271 { 272 /* 273 * Check whether this is a repeat, or aged record. We did this 274 * check once already when we first received the record - but 275 * we might have updated the window since then due to 276 * records we subsequently processed. 277 */ 278 replayok = dtls1_record_replay_check(s, bitmap); 279 } 280 281 if (!replayok || !dtls1_process_record(s, bitmap)) { 282 if (ossl_statem_in_error(s)) { 283 /* dtls1_process_record called SSLfatal() */ 284 return -1; 285 } 286 /* dump this record */ 287 rr->length = 0; 288 RECORD_LAYER_reset_packet_length(&s->rlayer); 289 continue; 290 } 291 292 if (dtls1_buffer_record(s, &(s->rlayer.d->processed_rcds), 293 SSL3_RECORD_get_seq_num(s->rlayer.rrec)) < 0) { 294 /* SSLfatal() already called */ 295 return 0; 296 } 297 } 298 } 299 300 /* 301 * sync epoch numbers once all the unprocessed records have been 302 * processed 303 */ 304 s->rlayer.d->processed_rcds.epoch = s->rlayer.d->r_epoch; 305 s->rlayer.d->unprocessed_rcds.epoch = s->rlayer.d->r_epoch + 1; 306 307 return 1; 308} 309 310/*- 311 * Return up to 'len' payload bytes received in 'type' records. 312 * 'type' is one of the following: 313 * 314 * - SSL3_RT_HANDSHAKE (when ssl3_get_message calls us) 315 * - SSL3_RT_APPLICATION_DATA (when ssl3_read calls us) 316 * - 0 (during a shutdown, no data has to be returned) 317 * 318 * If we don't have stored data to work from, read a SSL/TLS record first 319 * (possibly multiple records if we still don't have anything to return). 320 * 321 * This function must handle any surprises the peer may have for us, such as 322 * Alert records (e.g. close_notify) or renegotiation requests. ChangeCipherSpec 323 * messages are treated as if they were handshake messages *if* the |recd_type| 324 * argument is non NULL. 325 * Also if record payloads contain fragments too small to process, we store 326 * them until there is enough for the respective protocol (the record protocol 327 * may use arbitrary fragmentation and even interleaving): 328 * Change cipher spec protocol 329 * just 1 byte needed, no need for keeping anything stored 330 * Alert protocol 331 * 2 bytes needed (AlertLevel, AlertDescription) 332 * Handshake protocol 333 * 4 bytes needed (HandshakeType, uint24 length) -- we just have 334 * to detect unexpected Client Hello and Hello Request messages 335 * here, anything else is handled by higher layers 336 * Application data protocol 337 * none of our business 338 */ 339int dtls1_read_bytes(SSL *s, int type, int *recvd_type, unsigned char *buf, 340 size_t len, int peek, size_t *readbytes) 341{ 342 int i, j, iret; 343 size_t n; 344 SSL3_RECORD *rr; 345 void (*cb) (const SSL *ssl, int type2, int val) = NULL; 346 347 if (!SSL3_BUFFER_is_initialised(&s->rlayer.rbuf)) { 348 /* Not initialized yet */ 349 if (!ssl3_setup_buffers(s)) { 350 /* SSLfatal() already called */ 351 return -1; 352 } 353 } 354 355 if ((type && (type != SSL3_RT_APPLICATION_DATA) && 356 (type != SSL3_RT_HANDSHAKE)) || 357 (peek && (type != SSL3_RT_APPLICATION_DATA))) { 358 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_DTLS1_READ_BYTES, 359 ERR_R_INTERNAL_ERROR); 360 return -1; 361 } 362 363 if (!ossl_statem_get_in_handshake(s) && SSL_in_init(s)) { 364 /* type == SSL3_RT_APPLICATION_DATA */ 365 i = s->handshake_func(s); 366 /* SSLfatal() already called if appropriate */ 367 if (i < 0) 368 return i; 369 if (i == 0) 370 return -1; 371 } 372 373 start: 374 s->rwstate = SSL_NOTHING; 375 376 /*- 377 * s->s3->rrec.type - is the type of record 378 * s->s3->rrec.data, - data 379 * s->s3->rrec.off, - offset into 'data' for next read 380 * s->s3->rrec.length, - number of bytes. 381 */ 382 rr = s->rlayer.rrec; 383 384 /* 385 * We are not handshaking and have no data yet, so process data buffered 386 * during the last handshake in advance, if any. 387 */ 388 if (SSL_is_init_finished(s) && SSL3_RECORD_get_length(rr) == 0) { 389 pitem *item; 390 item = pqueue_pop(s->rlayer.d->buffered_app_data.q); 391 if (item) { 392#ifndef OPENSSL_NO_SCTP 393 /* Restore bio_dgram_sctp_rcvinfo struct */ 394 if (BIO_dgram_is_sctp(SSL_get_rbio(s))) { 395 DTLS1_RECORD_DATA *rdata = (DTLS1_RECORD_DATA *)item->data; 396 BIO_ctrl(SSL_get_rbio(s), BIO_CTRL_DGRAM_SCTP_SET_RCVINFO, 397 sizeof(rdata->recordinfo), &rdata->recordinfo); 398 } 399#endif 400 401 dtls1_copy_record(s, item); 402 403 OPENSSL_free(item->data); 404 pitem_free(item); 405 } 406 } 407 408 /* Check for timeout */ 409 if (dtls1_handle_timeout(s) > 0) { 410 goto start; 411 } else if (ossl_statem_in_error(s)) { 412 /* dtls1_handle_timeout() has failed with a fatal error */ 413 return -1; 414 } 415 416 /* get new packet if necessary */ 417 if ((SSL3_RECORD_get_length(rr) == 0) 418 || (s->rlayer.rstate == SSL_ST_READ_BODY)) { 419 RECORD_LAYER_set_numrpipes(&s->rlayer, 0); 420 iret = dtls1_get_record(s); 421 if (iret <= 0) { 422 iret = dtls1_read_failed(s, iret); 423 /* 424 * Anything other than a timeout is an error. SSLfatal() already 425 * called if appropriate. 426 */ 427 if (iret <= 0) 428 return iret; 429 else 430 goto start; 431 } 432 RECORD_LAYER_set_numrpipes(&s->rlayer, 1); 433 } 434 435 /* 436 * Reset the count of consecutive warning alerts if we've got a non-empty 437 * record that isn't an alert. 438 */ 439 if (SSL3_RECORD_get_type(rr) != SSL3_RT_ALERT 440 && SSL3_RECORD_get_length(rr) != 0) 441 s->rlayer.alert_count = 0; 442 443 if (SSL3_RECORD_get_type(rr) != SSL3_RT_HANDSHAKE 444 && SSL3_RECORD_get_type(rr) != SSL3_RT_CHANGE_CIPHER_SPEC 445 && !SSL_in_init(s) 446 && (s->d1->next_timeout.tv_sec != 0 447 || s->d1->next_timeout.tv_usec != 0)) { 448 /* 449 * The timer is still running but we've received something that isn't 450 * handshake data - so the peer must have finished processing our 451 * last handshake flight. Stop the timer. 452 */ 453 dtls1_stop_timer(s); 454 } 455 456 /* we now have a packet which can be read and processed */ 457 458 if (s->s3->change_cipher_spec /* set when we receive ChangeCipherSpec, 459 * reset by ssl3_get_finished */ 460 && (SSL3_RECORD_get_type(rr) != SSL3_RT_HANDSHAKE)) { 461 /* 462 * We now have application data between CCS and Finished. Most likely 463 * the packets were reordered on their way, so buffer the application 464 * data for later processing rather than dropping the connection. 465 */ 466 if (dtls1_buffer_record(s, &(s->rlayer.d->buffered_app_data), 467 SSL3_RECORD_get_seq_num(rr)) < 0) { 468 /* SSLfatal() already called */ 469 return -1; 470 } 471 SSL3_RECORD_set_length(rr, 0); 472 SSL3_RECORD_set_read(rr); 473 goto start; 474 } 475 476 /* 477 * If the other end has shut down, throw anything we read away (even in 478 * 'peek' mode) 479 */ 480 if (s->shutdown & SSL_RECEIVED_SHUTDOWN) { 481 SSL3_RECORD_set_length(rr, 0); 482 SSL3_RECORD_set_read(rr); 483 s->rwstate = SSL_NOTHING; 484 return 0; 485 } 486 487 if (type == SSL3_RECORD_get_type(rr) 488 || (SSL3_RECORD_get_type(rr) == SSL3_RT_CHANGE_CIPHER_SPEC 489 && type == SSL3_RT_HANDSHAKE && recvd_type != NULL)) { 490 /* 491 * SSL3_RT_APPLICATION_DATA or 492 * SSL3_RT_HANDSHAKE or 493 * SSL3_RT_CHANGE_CIPHER_SPEC 494 */ 495 /* 496 * make sure that we are not getting application data when we are 497 * doing a handshake for the first time 498 */ 499 if (SSL_in_init(s) && (type == SSL3_RT_APPLICATION_DATA) && 500 (s->enc_read_ctx == NULL)) { 501 SSLfatal(s, SSL_AD_UNEXPECTED_MESSAGE, SSL_F_DTLS1_READ_BYTES, 502 SSL_R_APP_DATA_IN_HANDSHAKE); 503 return -1; 504 } 505 506 if (recvd_type != NULL) 507 *recvd_type = SSL3_RECORD_get_type(rr); 508 509 if (len == 0) { 510 /* 511 * Mark a zero length record as read. This ensures multiple calls to 512 * SSL_read() with a zero length buffer will eventually cause 513 * SSL_pending() to report data as being available. 514 */ 515 if (SSL3_RECORD_get_length(rr) == 0) 516 SSL3_RECORD_set_read(rr); 517 return 0; 518 } 519 520 if (len > SSL3_RECORD_get_length(rr)) 521 n = SSL3_RECORD_get_length(rr); 522 else 523 n = len; 524 525 memcpy(buf, &(SSL3_RECORD_get_data(rr)[SSL3_RECORD_get_off(rr)]), n); 526 if (peek) { 527 if (SSL3_RECORD_get_length(rr) == 0) 528 SSL3_RECORD_set_read(rr); 529 } else { 530 SSL3_RECORD_sub_length(rr, n); 531 SSL3_RECORD_add_off(rr, n); 532 if (SSL3_RECORD_get_length(rr) == 0) { 533 s->rlayer.rstate = SSL_ST_READ_HEADER; 534 SSL3_RECORD_set_off(rr, 0); 535 SSL3_RECORD_set_read(rr); 536 } 537 } 538#ifndef OPENSSL_NO_SCTP 539 /* 540 * We might had to delay a close_notify alert because of reordered 541 * app data. If there was an alert and there is no message to read 542 * anymore, finally set shutdown. 543 */ 544 if (BIO_dgram_is_sctp(SSL_get_rbio(s)) && 545 s->d1->shutdown_received 546 && !BIO_dgram_sctp_msg_waiting(SSL_get_rbio(s))) { 547 s->shutdown |= SSL_RECEIVED_SHUTDOWN; 548 return 0; 549 } 550#endif 551 *readbytes = n; 552 return 1; 553 } 554 555 /* 556 * If we get here, then type != rr->type; if we have a handshake message, 557 * then it was unexpected (Hello Request or Client Hello). 558 */ 559 560 if (SSL3_RECORD_get_type(rr) == SSL3_RT_ALERT) { 561 unsigned int alert_level, alert_descr; 562 unsigned char *alert_bytes = SSL3_RECORD_get_data(rr) 563 + SSL3_RECORD_get_off(rr); 564 PACKET alert; 565 566 if (!PACKET_buf_init(&alert, alert_bytes, SSL3_RECORD_get_length(rr)) 567 || !PACKET_get_1(&alert, &alert_level) 568 || !PACKET_get_1(&alert, &alert_descr) 569 || PACKET_remaining(&alert) != 0) { 570 SSLfatal(s, SSL_AD_UNEXPECTED_MESSAGE, SSL_F_DTLS1_READ_BYTES, 571 SSL_R_INVALID_ALERT); 572 return -1; 573 } 574 575 if (s->msg_callback) 576 s->msg_callback(0, s->version, SSL3_RT_ALERT, alert_bytes, 2, s, 577 s->msg_callback_arg); 578 579 if (s->info_callback != NULL) 580 cb = s->info_callback; 581 else if (s->ctx->info_callback != NULL) 582 cb = s->ctx->info_callback; 583 584 if (cb != NULL) { 585 j = (alert_level << 8) | alert_descr; 586 cb(s, SSL_CB_READ_ALERT, j); 587 } 588 589 if (alert_level == SSL3_AL_WARNING) { 590 s->s3->warn_alert = alert_descr; 591 SSL3_RECORD_set_read(rr); 592 593 s->rlayer.alert_count++; 594 if (s->rlayer.alert_count == MAX_WARN_ALERT_COUNT) { 595 SSLfatal(s, SSL_AD_UNEXPECTED_MESSAGE, SSL_F_DTLS1_READ_BYTES, 596 SSL_R_TOO_MANY_WARN_ALERTS); 597 return -1; 598 } 599 600 if (alert_descr == SSL_AD_CLOSE_NOTIFY) { 601#ifndef OPENSSL_NO_SCTP 602 /* 603 * With SCTP and streams the socket may deliver app data 604 * after a close_notify alert. We have to check this first so 605 * that nothing gets discarded. 606 */ 607 if (BIO_dgram_is_sctp(SSL_get_rbio(s)) && 608 BIO_dgram_sctp_msg_waiting(SSL_get_rbio(s))) { 609 s->d1->shutdown_received = 1; 610 s->rwstate = SSL_READING; 611 BIO_clear_retry_flags(SSL_get_rbio(s)); 612 BIO_set_retry_read(SSL_get_rbio(s)); 613 return -1; 614 } 615#endif 616 s->shutdown |= SSL_RECEIVED_SHUTDOWN; 617 return 0; 618 } 619 } else if (alert_level == SSL3_AL_FATAL) { 620 char tmp[16]; 621 622 s->rwstate = SSL_NOTHING; 623 s->s3->fatal_alert = alert_descr; 624 SSLfatal(s, SSL_AD_NO_ALERT, SSL_F_DTLS1_READ_BYTES, 625 SSL_AD_REASON_OFFSET + alert_descr); 626 BIO_snprintf(tmp, sizeof tmp, "%d", alert_descr); 627 ERR_add_error_data(2, "SSL alert number ", tmp); 628 s->shutdown |= SSL_RECEIVED_SHUTDOWN; 629 SSL3_RECORD_set_read(rr); 630 SSL_CTX_remove_session(s->session_ctx, s->session); 631 return 0; 632 } else { 633 SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_F_DTLS1_READ_BYTES, 634 SSL_R_UNKNOWN_ALERT_TYPE); 635 return -1; 636 } 637 638 goto start; 639 } 640 641 if (s->shutdown & SSL_SENT_SHUTDOWN) { /* but we have not received a 642 * shutdown */ 643 s->rwstate = SSL_NOTHING; 644 SSL3_RECORD_set_length(rr, 0); 645 SSL3_RECORD_set_read(rr); 646 return 0; 647 } 648 649 if (SSL3_RECORD_get_type(rr) == SSL3_RT_CHANGE_CIPHER_SPEC) { 650 /* 651 * We can't process a CCS now, because previous handshake messages 652 * are still missing, so just drop it. 653 */ 654 SSL3_RECORD_set_length(rr, 0); 655 SSL3_RECORD_set_read(rr); 656 goto start; 657 } 658 659 /* 660 * Unexpected handshake message (Client Hello, or protocol violation) 661 */ 662 if ((SSL3_RECORD_get_type(rr) == SSL3_RT_HANDSHAKE) && 663 !ossl_statem_get_in_handshake(s)) { 664 struct hm_header_st msg_hdr; 665 666 /* 667 * This may just be a stale retransmit. Also sanity check that we have 668 * at least enough record bytes for a message header 669 */ 670 if (SSL3_RECORD_get_epoch(rr) != s->rlayer.d->r_epoch 671 || SSL3_RECORD_get_length(rr) < DTLS1_HM_HEADER_LENGTH) { 672 SSL3_RECORD_set_length(rr, 0); 673 SSL3_RECORD_set_read(rr); 674 goto start; 675 } 676 677 dtls1_get_message_header(rr->data, &msg_hdr); 678 679 /* 680 * If we are server, we may have a repeated FINISHED of the client 681 * here, then retransmit our CCS and FINISHED. 682 */ 683 if (msg_hdr.type == SSL3_MT_FINISHED) { 684 if (dtls1_check_timeout_num(s) < 0) { 685 /* SSLfatal) already called */ 686 return -1; 687 } 688 689 if (dtls1_retransmit_buffered_messages(s) <= 0) { 690 /* Fail if we encountered a fatal error */ 691 if (ossl_statem_in_error(s)) 692 return -1; 693 } 694 SSL3_RECORD_set_length(rr, 0); 695 SSL3_RECORD_set_read(rr); 696 if (!(s->mode & SSL_MODE_AUTO_RETRY)) { 697 if (SSL3_BUFFER_get_left(&s->rlayer.rbuf) == 0) { 698 /* no read-ahead left? */ 699 BIO *bio; 700 701 s->rwstate = SSL_READING; 702 bio = SSL_get_rbio(s); 703 BIO_clear_retry_flags(bio); 704 BIO_set_retry_read(bio); 705 return -1; 706 } 707 } 708 goto start; 709 } 710 711 /* 712 * To get here we must be trying to read app data but found handshake 713 * data. But if we're trying to read app data, and we're not in init 714 * (which is tested for at the top of this function) then init must be 715 * finished 716 */ 717 if (!ossl_assert(SSL_is_init_finished(s))) { 718 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_DTLS1_READ_BYTES, 719 ERR_R_INTERNAL_ERROR); 720 return -1; 721 } 722 723 /* We found handshake data, so we're going back into init */ 724 ossl_statem_set_in_init(s, 1); 725 726 i = s->handshake_func(s); 727 /* SSLfatal() called if appropriate */ 728 if (i < 0) 729 return i; 730 if (i == 0) 731 return -1; 732 733 if (!(s->mode & SSL_MODE_AUTO_RETRY)) { 734 if (SSL3_BUFFER_get_left(&s->rlayer.rbuf) == 0) { 735 /* no read-ahead left? */ 736 BIO *bio; 737 /* 738 * In the case where we try to read application data, but we 739 * trigger an SSL handshake, we return -1 with the retry 740 * option set. Otherwise renegotiation may cause nasty 741 * problems in the blocking world 742 */ 743 s->rwstate = SSL_READING; 744 bio = SSL_get_rbio(s); 745 BIO_clear_retry_flags(bio); 746 BIO_set_retry_read(bio); 747 return -1; 748 } 749 } 750 goto start; 751 } 752 753 switch (SSL3_RECORD_get_type(rr)) { 754 default: 755 SSLfatal(s, SSL_AD_UNEXPECTED_MESSAGE, SSL_F_DTLS1_READ_BYTES, 756 SSL_R_UNEXPECTED_RECORD); 757 return -1; 758 case SSL3_RT_CHANGE_CIPHER_SPEC: 759 case SSL3_RT_ALERT: 760 case SSL3_RT_HANDSHAKE: 761 /* 762 * we already handled all of these, with the possible exception of 763 * SSL3_RT_HANDSHAKE when ossl_statem_get_in_handshake(s) is true, but 764 * that should not happen when type != rr->type 765 */ 766 SSLfatal(s, SSL_AD_UNEXPECTED_MESSAGE, SSL_F_DTLS1_READ_BYTES, 767 ERR_R_INTERNAL_ERROR); 768 return -1; 769 case SSL3_RT_APPLICATION_DATA: 770 /* 771 * At this point, we were expecting handshake data, but have 772 * application data. If the library was running inside ssl3_read() 773 * (i.e. in_read_app_data is set) and it makes sense to read 774 * application data at this point (session renegotiation not yet 775 * started), we will indulge it. 776 */ 777 if (s->s3->in_read_app_data && 778 (s->s3->total_renegotiations != 0) && 779 ossl_statem_app_data_allowed(s)) { 780 s->s3->in_read_app_data = 2; 781 return -1; 782 } else { 783 SSLfatal(s, SSL_AD_UNEXPECTED_MESSAGE, SSL_F_DTLS1_READ_BYTES, 784 SSL_R_UNEXPECTED_RECORD); 785 return -1; 786 } 787 } 788 /* not reached */ 789} 790 791/* 792 * Call this to write data in records of type 'type' It will return <= 0 if 793 * not all data has been sent or non-blocking IO. 794 */ 795int dtls1_write_bytes(SSL *s, int type, const void *buf, size_t len, 796 size_t *written) 797{ 798 int i; 799 800 if (!ossl_assert(len <= SSL3_RT_MAX_PLAIN_LENGTH)) { 801 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_DTLS1_WRITE_BYTES, 802 ERR_R_INTERNAL_ERROR); 803 return -1; 804 } 805 s->rwstate = SSL_NOTHING; 806 i = do_dtls1_write(s, type, buf, len, 0, written); 807 return i; 808} 809 810int do_dtls1_write(SSL *s, int type, const unsigned char *buf, 811 size_t len, int create_empty_fragment, size_t *written) 812{ 813 unsigned char *p, *pseq; 814 int i, mac_size, clear = 0; 815 size_t prefix_len = 0; 816 int eivlen; 817 SSL3_RECORD wr; 818 SSL3_BUFFER *wb; 819 SSL_SESSION *sess; 820 821 wb = &s->rlayer.wbuf[0]; 822 823 /* 824 * first check if there is a SSL3_BUFFER still being written out. This 825 * will happen with non blocking IO 826 */ 827 if (!ossl_assert(SSL3_BUFFER_get_left(wb) == 0)) { 828 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_DO_DTLS1_WRITE, 829 ERR_R_INTERNAL_ERROR); 830 return 0; 831 } 832 833 /* If we have an alert to send, lets send it */ 834 if (s->s3->alert_dispatch) { 835 i = s->method->ssl_dispatch_alert(s); 836 if (i <= 0) 837 return i; 838 /* if it went, fall through and send more stuff */ 839 } 840 841 if (len == 0 && !create_empty_fragment) 842 return 0; 843 844 if (len > ssl_get_max_send_fragment(s)) { 845 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_DO_DTLS1_WRITE, 846 SSL_R_EXCEEDS_MAX_FRAGMENT_SIZE); 847 return 0; 848 } 849 850 sess = s->session; 851 852 if ((sess == NULL) || 853 (s->enc_write_ctx == NULL) || (EVP_MD_CTX_md(s->write_hash) == NULL)) 854 clear = 1; 855 856 if (clear) 857 mac_size = 0; 858 else { 859 mac_size = EVP_MD_CTX_size(s->write_hash); 860 if (mac_size < 0) { 861 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_DO_DTLS1_WRITE, 862 SSL_R_EXCEEDS_MAX_FRAGMENT_SIZE); 863 return -1; 864 } 865 } 866 867 p = SSL3_BUFFER_get_buf(wb) + prefix_len; 868 869 /* write the header */ 870 871 *(p++) = type & 0xff; 872 SSL3_RECORD_set_type(&wr, type); 873 /* 874 * Special case: for hello verify request, client version 1.0 and we 875 * haven't decided which version to use yet send back using version 1.0 876 * header: otherwise some clients will ignore it. 877 */ 878 if (s->method->version == DTLS_ANY_VERSION && 879 s->max_proto_version != DTLS1_BAD_VER) { 880 *(p++) = DTLS1_VERSION >> 8; 881 *(p++) = DTLS1_VERSION & 0xff; 882 } else { 883 *(p++) = s->version >> 8; 884 *(p++) = s->version & 0xff; 885 } 886 887 /* field where we are to write out packet epoch, seq num and len */ 888 pseq = p; 889 p += 10; 890 891 /* Explicit IV length, block ciphers appropriate version flag */ 892 if (s->enc_write_ctx) { 893 int mode = EVP_CIPHER_CTX_mode(s->enc_write_ctx); 894 if (mode == EVP_CIPH_CBC_MODE) { 895 eivlen = EVP_CIPHER_CTX_iv_length(s->enc_write_ctx); 896 if (eivlen <= 1) 897 eivlen = 0; 898 } 899 /* Need explicit part of IV for GCM mode */ 900 else if (mode == EVP_CIPH_GCM_MODE) 901 eivlen = EVP_GCM_TLS_EXPLICIT_IV_LEN; 902 else if (mode == EVP_CIPH_CCM_MODE) 903 eivlen = EVP_CCM_TLS_EXPLICIT_IV_LEN; 904 else 905 eivlen = 0; 906 } else 907 eivlen = 0; 908 909 /* lets setup the record stuff. */ 910 SSL3_RECORD_set_data(&wr, p + eivlen); /* make room for IV in case of CBC */ 911 SSL3_RECORD_set_length(&wr, len); 912 SSL3_RECORD_set_input(&wr, (unsigned char *)buf); 913 914 /* 915 * we now 'read' from wr.input, wr.length bytes into wr.data 916 */ 917 918 /* first we compress */ 919 if (s->compress != NULL) { 920 if (!ssl3_do_compress(s, &wr)) { 921 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_DO_DTLS1_WRITE, 922 SSL_R_COMPRESSION_FAILURE); 923 return -1; 924 } 925 } else { 926 memcpy(SSL3_RECORD_get_data(&wr), SSL3_RECORD_get_input(&wr), 927 SSL3_RECORD_get_length(&wr)); 928 SSL3_RECORD_reset_input(&wr); 929 } 930 931 /* 932 * we should still have the output to wr.data and the input from 933 * wr.input. Length should be wr.length. wr.data still points in the 934 * wb->buf 935 */ 936 937 if (!SSL_WRITE_ETM(s) && mac_size != 0) { 938 if (!s->method->ssl3_enc->mac(s, &wr, 939 &(p[SSL3_RECORD_get_length(&wr) + eivlen]), 940 1)) { 941 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_DO_DTLS1_WRITE, 942 ERR_R_INTERNAL_ERROR); 943 return -1; 944 } 945 SSL3_RECORD_add_length(&wr, mac_size); 946 } 947 948 /* this is true regardless of mac size */ 949 SSL3_RECORD_set_data(&wr, p); 950 SSL3_RECORD_reset_input(&wr); 951 952 if (eivlen) 953 SSL3_RECORD_add_length(&wr, eivlen); 954 955 if (s->method->ssl3_enc->enc(s, &wr, 1, 1) < 1) { 956 if (!ossl_statem_in_error(s)) { 957 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_DO_DTLS1_WRITE, 958 ERR_R_INTERNAL_ERROR); 959 } 960 return -1; 961 } 962 963 if (SSL_WRITE_ETM(s) && mac_size != 0) { 964 if (!s->method->ssl3_enc->mac(s, &wr, 965 &(p[SSL3_RECORD_get_length(&wr)]), 1)) { 966 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_DO_DTLS1_WRITE, 967 ERR_R_INTERNAL_ERROR); 968 return -1; 969 } 970 SSL3_RECORD_add_length(&wr, mac_size); 971 } 972 973 /* record length after mac and block padding */ 974 975 /* there's only one epoch between handshake and app data */ 976 977 s2n(s->rlayer.d->w_epoch, pseq); 978 979 memcpy(pseq, &(s->rlayer.write_sequence[2]), 6); 980 pseq += 6; 981 s2n(SSL3_RECORD_get_length(&wr), pseq); 982 983 if (s->msg_callback) 984 s->msg_callback(1, 0, SSL3_RT_HEADER, pseq - DTLS1_RT_HEADER_LENGTH, 985 DTLS1_RT_HEADER_LENGTH, s, s->msg_callback_arg); 986 987 /* 988 * we should now have wr.data pointing to the encrypted data, which is 989 * wr->length long 990 */ 991 SSL3_RECORD_set_type(&wr, type); /* not needed but helps for debugging */ 992 SSL3_RECORD_add_length(&wr, DTLS1_RT_HEADER_LENGTH); 993 994 ssl3_record_sequence_update(&(s->rlayer.write_sequence[0])); 995 996 if (create_empty_fragment) { 997 /* 998 * we are in a recursive call; just return the length, don't write 999 * out anything here 1000 */ 1001 *written = wr.length; 1002 return 1; 1003 } 1004 1005 /* now let's set up wb */ 1006 SSL3_BUFFER_set_left(wb, prefix_len + SSL3_RECORD_get_length(&wr)); 1007 SSL3_BUFFER_set_offset(wb, 0); 1008 1009 /* 1010 * memorize arguments so that ssl3_write_pending can detect bad write 1011 * retries later 1012 */ 1013 s->rlayer.wpend_tot = len; 1014 s->rlayer.wpend_buf = buf; 1015 s->rlayer.wpend_type = type; 1016 s->rlayer.wpend_ret = len; 1017 1018 /* we now just need to write the buffer. Calls SSLfatal() as required. */ 1019 return ssl3_write_pending(s, type, buf, len, written); 1020} 1021 1022DTLS1_BITMAP *dtls1_get_bitmap(SSL *s, SSL3_RECORD *rr, 1023 unsigned int *is_next_epoch) 1024{ 1025 1026 *is_next_epoch = 0; 1027 1028 /* In current epoch, accept HM, CCS, DATA, & ALERT */ 1029 if (rr->epoch == s->rlayer.d->r_epoch) 1030 return &s->rlayer.d->bitmap; 1031 1032 /* 1033 * Only HM and ALERT messages can be from the next epoch and only if we 1034 * have already processed all of the unprocessed records from the last 1035 * epoch 1036 */ 1037 else if (rr->epoch == (unsigned long)(s->rlayer.d->r_epoch + 1) && 1038 s->rlayer.d->unprocessed_rcds.epoch != s->rlayer.d->r_epoch && 1039 (rr->type == SSL3_RT_HANDSHAKE || rr->type == SSL3_RT_ALERT)) { 1040 *is_next_epoch = 1; 1041 return &s->rlayer.d->next_bitmap; 1042 } 1043 1044 return NULL; 1045} 1046 1047void dtls1_reset_seq_numbers(SSL *s, int rw) 1048{ 1049 unsigned char *seq; 1050 unsigned int seq_bytes = sizeof(s->rlayer.read_sequence); 1051 1052 if (rw & SSL3_CC_READ) { 1053 seq = s->rlayer.read_sequence; 1054 s->rlayer.d->r_epoch++; 1055 memcpy(&s->rlayer.d->bitmap, &s->rlayer.d->next_bitmap, 1056 sizeof(s->rlayer.d->bitmap)); 1057 memset(&s->rlayer.d->next_bitmap, 0, sizeof(s->rlayer.d->next_bitmap)); 1058 1059 /* 1060 * We must not use any buffered messages received from the previous 1061 * epoch 1062 */ 1063 dtls1_clear_received_buffer(s); 1064 } else { 1065 seq = s->rlayer.write_sequence; 1066 memcpy(s->rlayer.d->last_write_sequence, seq, 1067 sizeof(s->rlayer.write_sequence)); 1068 s->rlayer.d->w_epoch++; 1069 } 1070 1071 memset(seq, 0, seq_bytes); 1072} 1073