1 /* $OpenBSD: ssl_pkt.c,v 1.31 2020/08/30 15:40:20 jsing Exp $ */ 2 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com) 3 * All rights reserved. 4 * 5 * This package is an SSL implementation written 6 * by Eric Young (eay@cryptsoft.com). 7 * The implementation was written so as to conform with Netscapes SSL. 8 * 9 * This library is free for commercial and non-commercial use as long as 10 * the following conditions are aheared to. The following conditions 11 * apply to all code found in this distribution, be it the RC4, RSA, 12 * lhash, DES, etc., code; not just the SSL code. The SSL documentation 13 * included with this distribution is covered by the same copyright terms 14 * except that the holder is Tim Hudson (tjh@cryptsoft.com). 15 * 16 * Copyright remains Eric Young's, and as such any Copyright notices in 17 * the code are not to be removed. 18 * If this package is used in a product, Eric Young should be given attribution 19 * as the author of the parts of the library used. 20 * This can be in the form of a textual message at program startup or 21 * in documentation (online or textual) provided with the package. 22 * 23 * Redistribution and use in source and binary forms, with or without 24 * modification, are permitted provided that the following conditions 25 * are met: 26 * 1. Redistributions of source code must retain the copyright 27 * notice, this list of conditions and the following disclaimer. 28 * 2. Redistributions in binary form must reproduce the above copyright 29 * notice, this list of conditions and the following disclaimer in the 30 * documentation and/or other materials provided with the distribution. 31 * 3. All advertising materials mentioning features or use of this software 32 * must display the following acknowledgement: 33 * "This product includes cryptographic software written by 34 * Eric Young (eay@cryptsoft.com)" 35 * The word 'cryptographic' can be left out if the rouines from the library 36 * being used are not cryptographic related :-). 37 * 4. If you include any Windows specific code (or a derivative thereof) from 38 * the apps directory (application code) you must include an acknowledgement: 39 * "This product includes software written by Tim Hudson (tjh@cryptsoft.com)" 40 * 41 * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND 42 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 43 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 44 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 45 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 46 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 47 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 48 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 49 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 50 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 51 * SUCH DAMAGE. 52 * 53 * The licence and distribution terms for any publically available version or 54 * derivative of this code cannot be changed. i.e. this code cannot simply be 55 * copied and put under another distribution licence 56 * [including the GNU Public Licence.] 57 */ 58 /* ==================================================================== 59 * Copyright (c) 1998-2002 The OpenSSL Project. All rights reserved. 60 * 61 * Redistribution and use in source and binary forms, with or without 62 * modification, are permitted provided that the following conditions 63 * are met: 64 * 65 * 1. Redistributions of source code must retain the above copyright 66 * notice, this list of conditions and the following disclaimer. 67 * 68 * 2. Redistributions in binary form must reproduce the above copyright 69 * notice, this list of conditions and the following disclaimer in 70 * the documentation and/or other materials provided with the 71 * distribution. 72 * 73 * 3. All advertising materials mentioning features or use of this 74 * software must display the following acknowledgment: 75 * "This product includes software developed by the OpenSSL Project 76 * for use in the OpenSSL Toolkit. (http://www.openssl.org/)" 77 * 78 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to 79 * endorse or promote products derived from this software without 80 * prior written permission. For written permission, please contact 81 * openssl-core@openssl.org. 82 * 83 * 5. Products derived from this software may not be called "OpenSSL" 84 * nor may "OpenSSL" appear in their names without prior written 85 * permission of the OpenSSL Project. 86 * 87 * 6. Redistributions of any form whatsoever must retain the following 88 * acknowledgment: 89 * "This product includes software developed by the OpenSSL Project 90 * for use in the OpenSSL Toolkit (http://www.openssl.org/)" 91 * 92 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY 93 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 94 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 95 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR 96 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 97 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 98 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 99 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 100 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, 101 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 102 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED 103 * OF THE POSSIBILITY OF SUCH DAMAGE. 104 * ==================================================================== 105 * 106 * This product includes cryptographic software written by Eric Young 107 * (eay@cryptsoft.com). This product includes software written by Tim 108 * Hudson (tjh@cryptsoft.com). 109 * 110 */ 111 112 #include <errno.h> 113 #include <stdio.h> 114 115 #include "ssl_locl.h" 116 117 #include <openssl/buffer.h> 118 #include <openssl/evp.h> 119 120 #include "bytestring.h" 121 122 static int do_ssl3_write(SSL *s, int type, const unsigned char *buf, 123 unsigned int len); 124 static int ssl3_get_record(SSL *s); 125 126 /* 127 * Force a WANT_READ return for certain error conditions where 128 * we don't want to spin internally. 129 */ 130 static void 131 ssl_force_want_read(SSL *s) 132 { 133 BIO * bio; 134 135 bio = SSL_get_rbio(s); 136 BIO_clear_retry_flags(bio); 137 BIO_set_retry_read(bio); 138 s->internal->rwstate = SSL_READING; 139 } 140 141 /* 142 * If extend == 0, obtain new n-byte packet; if extend == 1, increase 143 * packet by another n bytes. 144 * The packet will be in the sub-array of S3I(s)->rbuf.buf specified 145 * by s->internal->packet and s->internal->packet_length. 146 * (If s->internal->read_ahead is set, 'max' bytes may be stored in rbuf 147 * [plus s->internal->packet_length bytes if extend == 1].) 148 */ 149 static int 150 ssl3_read_n(SSL *s, int n, int max, int extend) 151 { 152 int i, len, left; 153 size_t align; 154 unsigned char *pkt; 155 SSL3_BUFFER_INTERNAL *rb; 156 157 if (n <= 0) 158 return n; 159 160 rb = &(S3I(s)->rbuf); 161 if (rb->buf == NULL) 162 if (!ssl3_setup_read_buffer(s)) 163 return -1; 164 165 left = rb->left; 166 align = (size_t)rb->buf + SSL3_RT_HEADER_LENGTH; 167 align = (-align) & (SSL3_ALIGN_PAYLOAD - 1); 168 169 if (!extend) { 170 /* start with empty packet ... */ 171 if (left == 0) 172 rb->offset = align; 173 else if (align != 0 && left >= SSL3_RT_HEADER_LENGTH) { 174 /* check if next packet length is large 175 * enough to justify payload alignment... */ 176 pkt = rb->buf + rb->offset; 177 if (pkt[0] == SSL3_RT_APPLICATION_DATA && 178 (pkt[3]<<8|pkt[4]) >= 128) { 179 /* Note that even if packet is corrupted 180 * and its length field is insane, we can 181 * only be led to wrong decision about 182 * whether memmove will occur or not. 183 * Header values has no effect on memmove 184 * arguments and therefore no buffer 185 * overrun can be triggered. */ 186 memmove(rb->buf + align, pkt, left); 187 rb->offset = align; 188 } 189 } 190 s->internal->packet = rb->buf + rb->offset; 191 s->internal->packet_length = 0; 192 /* ... now we can act as if 'extend' was set */ 193 } 194 195 /* For DTLS/UDP reads should not span multiple packets 196 * because the read operation returns the whole packet 197 * at once (as long as it fits into the buffer). */ 198 if (SSL_IS_DTLS(s)) { 199 if (left > 0 && n > left) 200 n = left; 201 } 202 203 /* if there is enough in the buffer from a previous read, take some */ 204 if (left >= n) { 205 s->internal->packet_length += n; 206 rb->left = left - n; 207 rb->offset += n; 208 return (n); 209 } 210 211 /* else we need to read more data */ 212 213 len = s->internal->packet_length; 214 pkt = rb->buf + align; 215 /* Move any available bytes to front of buffer: 216 * 'len' bytes already pointed to by 'packet', 217 * 'left' extra ones at the end */ 218 if (s->internal->packet != pkt) { 219 /* len > 0 */ 220 memmove(pkt, s->internal->packet, len + left); 221 s->internal->packet = pkt; 222 rb->offset = len + align; 223 } 224 225 if (n > (int)(rb->len - rb->offset)) { 226 /* does not happen */ 227 SSLerror(s, ERR_R_INTERNAL_ERROR); 228 return -1; 229 } 230 231 if (!s->internal->read_ahead) { 232 /* ignore max parameter */ 233 max = n; 234 } else { 235 if (max < n) 236 max = n; 237 if (max > (int)(rb->len - rb->offset)) 238 max = rb->len - rb->offset; 239 } 240 241 while (left < n) { 242 /* Now we have len+left bytes at the front of S3I(s)->rbuf.buf 243 * and need to read in more until we have len+n (up to 244 * len+max if possible) */ 245 246 errno = 0; 247 if (s->rbio != NULL) { 248 s->internal->rwstate = SSL_READING; 249 i = BIO_read(s->rbio, pkt + len + left, max - left); 250 } else { 251 SSLerror(s, SSL_R_READ_BIO_NOT_SET); 252 i = -1; 253 } 254 255 if (i <= 0) { 256 rb->left = left; 257 if (s->internal->mode & SSL_MODE_RELEASE_BUFFERS && 258 !SSL_IS_DTLS(s)) { 259 if (len + left == 0) 260 ssl3_release_read_buffer(s); 261 } 262 return (i); 263 } 264 left += i; 265 266 /* 267 * reads should *never* span multiple packets for DTLS because 268 * the underlying transport protocol is message oriented as 269 * opposed to byte oriented as in the TLS case. 270 */ 271 if (SSL_IS_DTLS(s)) { 272 if (n > left) 273 n = left; /* makes the while condition false */ 274 } 275 } 276 277 /* done reading, now the book-keeping */ 278 rb->offset += n; 279 rb->left = left - n; 280 s->internal->packet_length += n; 281 s->internal->rwstate = SSL_NOTHING; 282 283 return (n); 284 } 285 286 int 287 ssl3_packet_read(SSL *s, int plen) 288 { 289 int n; 290 291 n = ssl3_read_n(s, plen, S3I(s)->rbuf.len, 0); 292 if (n <= 0) 293 return n; 294 if (s->internal->packet_length < plen) 295 return s->internal->packet_length; 296 297 return plen; 298 } 299 300 int 301 ssl3_packet_extend(SSL *s, int plen) 302 { 303 int rlen, n; 304 305 if (s->internal->packet_length >= plen) 306 return plen; 307 rlen = plen - s->internal->packet_length; 308 309 n = ssl3_read_n(s, rlen, rlen, 1); 310 if (n <= 0) 311 return n; 312 if (s->internal->packet_length < plen) 313 return s->internal->packet_length; 314 315 return plen; 316 } 317 318 /* Call this to get a new input record. 319 * It will return <= 0 if more data is needed, normally due to an error 320 * or non-blocking IO. 321 * When it finishes, one packet has been decoded and can be found in 322 * ssl->s3->internal->rrec.type - is the type of record 323 * ssl->s3->internal->rrec.data, - data 324 * ssl->s3->internal->rrec.length, - number of bytes 325 */ 326 /* used only by ssl3_read_bytes */ 327 static int 328 ssl3_get_record(SSL *s) 329 { 330 int al; 331 int enc_err, n, i, ret = -1; 332 SSL3_RECORD_INTERNAL *rr; 333 SSL_SESSION *sess; 334 unsigned char md[EVP_MAX_MD_SIZE]; 335 unsigned int mac_size, orig_len; 336 337 rr = &(S3I(s)->rrec); 338 sess = s->session; 339 340 again: 341 /* check if we have the header */ 342 if ((s->internal->rstate != SSL_ST_READ_BODY) || 343 (s->internal->packet_length < SSL3_RT_HEADER_LENGTH)) { 344 CBS header; 345 uint16_t len, ssl_version; 346 uint8_t type; 347 348 n = ssl3_packet_read(s, SSL3_RT_HEADER_LENGTH); 349 if (n <= 0) 350 return (n); 351 352 s->internal->mac_packet = 1; 353 s->internal->rstate = SSL_ST_READ_BODY; 354 355 if (s->server && s->internal->first_packet) { 356 if ((ret = ssl_server_legacy_first_packet(s)) != 1) 357 return (ret); 358 ret = -1; 359 } 360 361 CBS_init(&header, s->internal->packet, SSL3_RT_HEADER_LENGTH); 362 363 /* Pull apart the header into the SSL3_RECORD_INTERNAL */ 364 if (!CBS_get_u8(&header, &type) || 365 !CBS_get_u16(&header, &ssl_version) || 366 !CBS_get_u16(&header, &len)) { 367 SSLerror(s, SSL_R_BAD_PACKET_LENGTH); 368 goto err; 369 } 370 371 rr->type = type; 372 rr->length = len; 373 374 /* Lets check version */ 375 if (!s->internal->first_packet && ssl_version != s->version) { 376 SSLerror(s, SSL_R_WRONG_VERSION_NUMBER); 377 if ((s->version & 0xFF00) == (ssl_version & 0xFF00) && 378 !s->internal->enc_write_ctx && !s->internal->write_hash) 379 /* Send back error using their minor version number :-) */ 380 s->version = ssl_version; 381 al = SSL_AD_PROTOCOL_VERSION; 382 goto f_err; 383 } 384 385 if ((ssl_version >> 8) != SSL3_VERSION_MAJOR) { 386 SSLerror(s, SSL_R_WRONG_VERSION_NUMBER); 387 goto err; 388 } 389 390 if (rr->length > S3I(s)->rbuf.len - SSL3_RT_HEADER_LENGTH) { 391 al = SSL_AD_RECORD_OVERFLOW; 392 SSLerror(s, SSL_R_PACKET_LENGTH_TOO_LONG); 393 goto f_err; 394 } 395 396 /* now s->internal->rstate == SSL_ST_READ_BODY */ 397 } 398 399 /* s->internal->rstate == SSL_ST_READ_BODY, get and decode the data */ 400 401 n = ssl3_packet_extend(s, SSL3_RT_HEADER_LENGTH + rr->length); 402 if (n <= 0) 403 return (n); 404 if (n != SSL3_RT_HEADER_LENGTH + rr->length) 405 return (n); 406 407 s->internal->rstate = SSL_ST_READ_HEADER; /* set state for later operations */ 408 409 /* At this point, s->internal->packet_length == SSL3_RT_HEADER_LNGTH + rr->length, 410 * and we have that many bytes in s->internal->packet 411 */ 412 rr->input = &(s->internal->packet[SSL3_RT_HEADER_LENGTH]); 413 414 /* ok, we can now read from 's->internal->packet' data into 'rr' 415 * rr->input points at rr->length bytes, which 416 * need to be copied into rr->data by either 417 * the decryption or by the decompression 418 * When the data is 'copied' into the rr->data buffer, 419 * rr->input will be pointed at the new buffer */ 420 421 /* We now have - encrypted [ MAC [ compressed [ plain ] ] ] 422 * rr->length bytes of encrypted compressed stuff. */ 423 424 /* check is not needed I believe */ 425 if (rr->length > SSL3_RT_MAX_ENCRYPTED_LENGTH) { 426 al = SSL_AD_RECORD_OVERFLOW; 427 SSLerror(s, SSL_R_ENCRYPTED_LENGTH_TOO_LONG); 428 goto f_err; 429 } 430 431 /* decrypt in place in 'rr->input' */ 432 rr->data = rr->input; 433 434 /* enc_err is: 435 * 0: (in non-constant time) if the record is publically invalid. 436 * 1: if the padding is valid 437 * -1: if the padding is invalid */ 438 if ((enc_err = tls1_enc(s, 0)) == 0) { 439 al = SSL_AD_BAD_RECORD_MAC; 440 SSLerror(s, SSL_R_BLOCK_CIPHER_PAD_IS_WRONG); 441 goto f_err; 442 } 443 444 /* r->length is now the compressed data plus mac */ 445 if ((sess != NULL) && (s->enc_read_ctx != NULL) && 446 (EVP_MD_CTX_md(s->read_hash) != NULL)) { 447 /* s->read_hash != NULL => mac_size != -1 */ 448 unsigned char *mac = NULL; 449 unsigned char mac_tmp[EVP_MAX_MD_SIZE]; 450 451 mac_size = EVP_MD_CTX_size(s->read_hash); 452 OPENSSL_assert(mac_size <= EVP_MAX_MD_SIZE); 453 454 orig_len = rr->length + rr->padding_length; 455 456 /* orig_len is the length of the record before any padding was 457 * removed. This is public information, as is the MAC in use, 458 * therefore we can safely process the record in a different 459 * amount of time if it's too short to possibly contain a MAC. 460 */ 461 if (orig_len < mac_size || 462 /* CBC records must have a padding length byte too. */ 463 (EVP_CIPHER_CTX_mode(s->enc_read_ctx) == EVP_CIPH_CBC_MODE && 464 orig_len < mac_size + 1)) { 465 al = SSL_AD_DECODE_ERROR; 466 SSLerror(s, SSL_R_LENGTH_TOO_SHORT); 467 goto f_err; 468 } 469 470 if (EVP_CIPHER_CTX_mode(s->enc_read_ctx) == EVP_CIPH_CBC_MODE) { 471 /* We update the length so that the TLS header bytes 472 * can be constructed correctly but we need to extract 473 * the MAC in constant time from within the record, 474 * without leaking the contents of the padding bytes. 475 * */ 476 mac = mac_tmp; 477 ssl3_cbc_copy_mac(mac_tmp, rr, mac_size, orig_len); 478 rr->length -= mac_size; 479 } else { 480 /* In this case there's no padding, so |orig_len| 481 * equals |rec->length| and we checked that there's 482 * enough bytes for |mac_size| above. */ 483 rr->length -= mac_size; 484 mac = &rr->data[rr->length]; 485 } 486 487 i = tls1_mac(s,md,0 /* not send */); 488 if (i < 0 || mac == NULL || 489 timingsafe_memcmp(md, mac, (size_t)mac_size) != 0) 490 enc_err = -1; 491 if (rr->length > 492 SSL3_RT_MAX_COMPRESSED_LENGTH + mac_size) 493 enc_err = -1; 494 } 495 496 if (enc_err < 0) { 497 /* 498 * A separate 'decryption_failed' alert was introduced with 499 * TLS 1.0, SSL 3.0 only has 'bad_record_mac'. But unless a 500 * decryption failure is directly visible from the ciphertext 501 * anyway, we should not reveal which kind of error 502 * occurred -- this might become visible to an attacker 503 * (e.g. via a logfile) 504 */ 505 al = SSL_AD_BAD_RECORD_MAC; 506 SSLerror(s, SSL_R_DECRYPTION_FAILED_OR_BAD_RECORD_MAC); 507 goto f_err; 508 } 509 510 if (rr->length > SSL3_RT_MAX_PLAIN_LENGTH) { 511 al = SSL_AD_RECORD_OVERFLOW; 512 SSLerror(s, SSL_R_DATA_LENGTH_TOO_LONG); 513 goto f_err; 514 } 515 516 rr->off = 0; 517 /* 518 * So at this point the following is true 519 * 520 * ssl->s3->internal->rrec.type is the type of record 521 * ssl->s3->internal->rrec.length == number of bytes in record 522 * ssl->s3->internal->rrec.off == offset to first valid byte 523 * ssl->s3->internal->rrec.data == where to take bytes from, increment 524 * after use :-). 525 */ 526 527 /* we have pulled in a full packet so zero things */ 528 s->internal->packet_length = 0; 529 530 if (rr->length == 0) { 531 /* 532 * CBC countermeasures for known IV weaknesses 533 * can legitimately insert a single empty record, 534 * so we allow ourselves to read once past a single 535 * empty record without forcing want_read. 536 */ 537 if (s->internal->empty_record_count++ > SSL_MAX_EMPTY_RECORDS) { 538 SSLerror(s, SSL_R_PEER_BEHAVING_BADLY); 539 return -1; 540 } 541 if (s->internal->empty_record_count > 1) { 542 ssl_force_want_read(s); 543 return -1; 544 } 545 goto again; 546 } else { 547 s->internal->empty_record_count = 0; 548 } 549 550 return (1); 551 552 f_err: 553 ssl3_send_alert(s, SSL3_AL_FATAL, al); 554 err: 555 return (ret); 556 } 557 558 /* Call this to write data in records of type 'type' 559 * It will return <= 0 if not all data has been sent or non-blocking IO. 560 */ 561 int 562 ssl3_write_bytes(SSL *s, int type, const void *buf_, int len) 563 { 564 const unsigned char *buf = buf_; 565 unsigned int tot, n, nw; 566 int i; 567 568 if (len < 0) { 569 SSLerror(s, ERR_R_INTERNAL_ERROR); 570 return -1; 571 } 572 573 s->internal->rwstate = SSL_NOTHING; 574 tot = S3I(s)->wnum; 575 S3I(s)->wnum = 0; 576 577 if (SSL_in_init(s) && !s->internal->in_handshake) { 578 i = s->internal->handshake_func(s); 579 if (i < 0) 580 return (i); 581 if (i == 0) { 582 SSLerror(s, SSL_R_SSL_HANDSHAKE_FAILURE); 583 return -1; 584 } 585 } 586 587 if (len < tot) 588 len = tot; 589 n = (len - tot); 590 for (;;) { 591 if (n > s->max_send_fragment) 592 nw = s->max_send_fragment; 593 else 594 nw = n; 595 596 i = do_ssl3_write(s, type, &(buf[tot]), nw); 597 if (i <= 0) { 598 S3I(s)->wnum = tot; 599 return i; 600 } 601 602 if ((i == (int)n) || (type == SSL3_RT_APPLICATION_DATA && 603 (s->internal->mode & SSL_MODE_ENABLE_PARTIAL_WRITE))) { 604 /* 605 * Next chunk of data should get another prepended 606 * empty fragment in ciphersuites with known-IV 607 * weakness. 608 */ 609 S3I(s)->empty_fragment_done = 0; 610 611 return tot + i; 612 } 613 614 n -= i; 615 tot += i; 616 } 617 } 618 619 static int 620 do_ssl3_write(SSL *s, int type, const unsigned char *buf, unsigned int len) 621 { 622 SSL3_BUFFER_INTERNAL *wb = &(S3I(s)->wbuf); 623 SSL_SESSION *sess = s->session; 624 int need_empty_fragment = 0; 625 size_t align, out_len; 626 uint16_t version; 627 CBB cbb; 628 int ret; 629 630 memset(&cbb, 0, sizeof(cbb)); 631 632 if (wb->buf == NULL) 633 if (!ssl3_setup_write_buffer(s)) 634 return -1; 635 636 /* 637 * First check if there is a SSL3_BUFFER_INTERNAL still being written 638 * out. This will happen with non blocking IO. 639 */ 640 if (wb->left != 0) 641 return (ssl3_write_pending(s, type, buf, len)); 642 643 /* If we have an alert to send, let's send it. */ 644 if (S3I(s)->alert_dispatch) { 645 if ((ret = s->method->ssl_dispatch_alert(s)) <= 0) 646 return (ret); 647 /* If it went, fall through and send more stuff. */ 648 649 /* We may have released our buffer, if so get it again. */ 650 if (wb->buf == NULL) 651 if (!ssl3_setup_write_buffer(s)) 652 return -1; 653 } 654 655 if (len == 0) 656 return 0; 657 658 /* 659 * Some servers hang if initial client hello is larger than 256 660 * bytes and record version number > TLS 1.0. 661 */ 662 version = s->version; 663 if (S3I(s)->hs.state == SSL3_ST_CW_CLNT_HELLO_B && !s->internal->renegotiate && 664 TLS1_get_version(s) > TLS1_VERSION) 665 version = TLS1_VERSION; 666 667 /* 668 * Countermeasure against known-IV weakness in CBC ciphersuites 669 * (see http://www.openssl.org/~bodo/tls-cbc.txt). Note that this 670 * is unnecessary for AEAD. 671 */ 672 if (sess != NULL && s->internal->enc_write_ctx != NULL && 673 EVP_MD_CTX_md(s->internal->write_hash) != NULL) { 674 if (S3I(s)->need_empty_fragments && 675 !S3I(s)->empty_fragment_done && 676 type == SSL3_RT_APPLICATION_DATA) 677 need_empty_fragment = 1; 678 } 679 680 /* 681 * An extra fragment would be a couple of cipher blocks, which would 682 * be a multiple of SSL3_ALIGN_PAYLOAD, so if we want to align the real 683 * payload, then we can just simply pretend we have two headers. 684 */ 685 align = (size_t)wb->buf + SSL3_RT_HEADER_LENGTH; 686 if (need_empty_fragment) 687 align += SSL3_RT_HEADER_LENGTH; 688 align = (-align) & (SSL3_ALIGN_PAYLOAD - 1); 689 wb->offset = align; 690 691 if (!CBB_init_fixed(&cbb, wb->buf + align, wb->len - align)) 692 goto err; 693 694 tls12_record_layer_set_version(s->internal->rl, version); 695 696 if (need_empty_fragment) { 697 if (!tls12_record_layer_seal_record(s->internal->rl, type, 698 buf, 0, &cbb)) 699 goto err; 700 S3I(s)->empty_fragment_done = 1; 701 } 702 703 if (!tls12_record_layer_seal_record(s->internal->rl, type, buf, len, &cbb)) 704 goto err; 705 706 if (!CBB_finish(&cbb, NULL, &out_len)) 707 goto err; 708 709 wb->left = out_len; 710 711 /* 712 * Memorize arguments so that ssl3_write_pending can detect 713 * bad write retries later. 714 */ 715 S3I(s)->wpend_tot = len; 716 S3I(s)->wpend_buf = buf; 717 S3I(s)->wpend_type = type; 718 S3I(s)->wpend_ret = len; 719 720 /* We now just need to write the buffer. */ 721 return ssl3_write_pending(s, type, buf, len); 722 723 err: 724 CBB_cleanup(&cbb); 725 726 return -1; 727 } 728 729 /* if S3I(s)->wbuf.left != 0, we need to call this */ 730 int 731 ssl3_write_pending(SSL *s, int type, const unsigned char *buf, unsigned int len) 732 { 733 int i; 734 SSL3_BUFFER_INTERNAL *wb = &(S3I(s)->wbuf); 735 736 /* XXXX */ 737 if ((S3I(s)->wpend_tot > (int)len) || ((S3I(s)->wpend_buf != buf) && 738 !(s->internal->mode & SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER)) || 739 (S3I(s)->wpend_type != type)) { 740 SSLerror(s, SSL_R_BAD_WRITE_RETRY); 741 return (-1); 742 } 743 744 for (;;) { 745 errno = 0; 746 if (s->wbio != NULL) { 747 s->internal->rwstate = SSL_WRITING; 748 i = BIO_write(s->wbio, (char *)&(wb->buf[wb->offset]), 749 (unsigned int)wb->left); 750 } else { 751 SSLerror(s, SSL_R_BIO_NOT_SET); 752 i = -1; 753 } 754 if (i == wb->left) { 755 wb->left = 0; 756 wb->offset += i; 757 if (s->internal->mode & SSL_MODE_RELEASE_BUFFERS && 758 !SSL_IS_DTLS(s)) 759 ssl3_release_write_buffer(s); 760 s->internal->rwstate = SSL_NOTHING; 761 return (S3I(s)->wpend_ret); 762 } else if (i <= 0) { 763 /* 764 * For DTLS, just drop it. That's kind of the 765 * whole point in using a datagram service. 766 */ 767 if (SSL_IS_DTLS(s)) 768 wb->left = 0; 769 return (i); 770 } 771 wb->offset += i; 772 wb->left -= i; 773 } 774 } 775 776 /* Return up to 'len' payload bytes received in 'type' records. 777 * 'type' is one of the following: 778 * 779 * - SSL3_RT_HANDSHAKE (when ssl3_get_message calls us) 780 * - SSL3_RT_APPLICATION_DATA (when ssl3_read calls us) 781 * - 0 (during a shutdown, no data has to be returned) 782 * 783 * If we don't have stored data to work from, read a SSL/TLS record first 784 * (possibly multiple records if we still don't have anything to return). 785 * 786 * This function must handle any surprises the peer may have for us, such as 787 * Alert records (e.g. close_notify), ChangeCipherSpec records (not really 788 * a surprise, but handled as if it were), or renegotiation requests. 789 * Also if record payloads contain fragments too small to process, we store 790 * them until there is enough for the respective protocol (the record protocol 791 * may use arbitrary fragmentation and even interleaving): 792 * Change cipher spec protocol 793 * just 1 byte needed, no need for keeping anything stored 794 * Alert protocol 795 * 2 bytes needed (AlertLevel, AlertDescription) 796 * Handshake protocol 797 * 4 bytes needed (HandshakeType, uint24 length) -- we just have 798 * to detect unexpected Client Hello and Hello Request messages 799 * here, anything else is handled by higher layers 800 * Application data protocol 801 * none of our business 802 */ 803 int 804 ssl3_read_bytes(SSL *s, int type, unsigned char *buf, int len, int peek) 805 { 806 void (*cb)(const SSL *ssl, int type2, int val) = NULL; 807 int al, i, j, ret, rrcount = 0; 808 unsigned int n; 809 SSL3_RECORD_INTERNAL *rr; 810 811 if (S3I(s)->rbuf.buf == NULL) /* Not initialized yet */ 812 if (!ssl3_setup_read_buffer(s)) 813 return (-1); 814 815 if (len < 0) { 816 SSLerror(s, ERR_R_INTERNAL_ERROR); 817 return -1; 818 } 819 820 if ((type && type != SSL3_RT_APPLICATION_DATA && 821 type != SSL3_RT_HANDSHAKE) || 822 (peek && (type != SSL3_RT_APPLICATION_DATA))) { 823 SSLerror(s, ERR_R_INTERNAL_ERROR); 824 return -1; 825 } 826 827 if ((type == SSL3_RT_HANDSHAKE) && 828 (S3I(s)->handshake_fragment_len > 0)) { 829 /* (partially) satisfy request from storage */ 830 unsigned char *src = S3I(s)->handshake_fragment; 831 unsigned char *dst = buf; 832 unsigned int k; 833 834 /* peek == 0 */ 835 n = 0; 836 while ((len > 0) && (S3I(s)->handshake_fragment_len > 0)) { 837 *dst++ = *src++; 838 len--; 839 S3I(s)->handshake_fragment_len--; 840 n++; 841 } 842 /* move any remaining fragment bytes: */ 843 for (k = 0; k < S3I(s)->handshake_fragment_len; k++) 844 S3I(s)->handshake_fragment[k] = *src++; 845 return n; 846 } 847 848 /* 849 * Now S3I(s)->handshake_fragment_len == 0 if 850 * type == SSL3_RT_HANDSHAKE. 851 */ 852 if (!s->internal->in_handshake && SSL_in_init(s)) { 853 /* type == SSL3_RT_APPLICATION_DATA */ 854 i = s->internal->handshake_func(s); 855 if (i < 0) 856 return (i); 857 if (i == 0) { 858 SSLerror(s, SSL_R_SSL_HANDSHAKE_FAILURE); 859 return (-1); 860 } 861 } 862 863 start: 864 /* 865 * Do not process more than three consecutive records, otherwise the 866 * peer can cause us to loop indefinitely. Instead, return with an 867 * SSL_ERROR_WANT_READ so the caller can choose when to handle further 868 * processing. In the future, the total number of non-handshake and 869 * non-application data records per connection should probably also be 870 * limited... 871 */ 872 if (rrcount++ >= 3) { 873 ssl_force_want_read(s); 874 return -1; 875 } 876 877 s->internal->rwstate = SSL_NOTHING; 878 879 /* 880 * S3I(s)->rrec.type - is the type of record 881 * S3I(s)->rrec.data, - data 882 * S3I(s)->rrec.off, - offset into 'data' for next read 883 * S3I(s)->rrec.length, - number of bytes. 884 */ 885 rr = &(S3I(s)->rrec); 886 887 /* get new packet if necessary */ 888 if ((rr->length == 0) || (s->internal->rstate == SSL_ST_READ_BODY)) { 889 ret = ssl3_get_record(s); 890 if (ret <= 0) 891 return (ret); 892 } 893 894 /* we now have a packet which can be read and processed */ 895 896 if (S3I(s)->change_cipher_spec /* set when we receive ChangeCipherSpec, 897 * reset by ssl3_get_finished */ 898 && (rr->type != SSL3_RT_HANDSHAKE)) { 899 al = SSL_AD_UNEXPECTED_MESSAGE; 900 SSLerror(s, SSL_R_DATA_BETWEEN_CCS_AND_FINISHED); 901 goto f_err; 902 } 903 904 /* If the other end has shut down, throw anything we read away 905 * (even in 'peek' mode) */ 906 if (s->internal->shutdown & SSL_RECEIVED_SHUTDOWN) { 907 rr->length = 0; 908 s->internal->rwstate = SSL_NOTHING; 909 return (0); 910 } 911 912 913 /* SSL3_RT_APPLICATION_DATA or SSL3_RT_HANDSHAKE */ 914 if (type == rr->type) { 915 /* make sure that we are not getting application data when we 916 * are doing a handshake for the first time */ 917 if (SSL_in_init(s) && (type == SSL3_RT_APPLICATION_DATA) && 918 (s->enc_read_ctx == NULL)) { 919 al = SSL_AD_UNEXPECTED_MESSAGE; 920 SSLerror(s, SSL_R_APP_DATA_IN_HANDSHAKE); 921 goto f_err; 922 } 923 924 if (len <= 0) 925 return (len); 926 927 if ((unsigned int)len > rr->length) 928 n = rr->length; 929 else 930 n = (unsigned int)len; 931 932 memcpy(buf, &(rr->data[rr->off]), n); 933 if (!peek) { 934 memset(&(rr->data[rr->off]), 0, n); 935 rr->length -= n; 936 rr->off += n; 937 if (rr->length == 0) { 938 s->internal->rstate = SSL_ST_READ_HEADER; 939 rr->off = 0; 940 if (s->internal->mode & SSL_MODE_RELEASE_BUFFERS && 941 S3I(s)->rbuf.left == 0) 942 ssl3_release_read_buffer(s); 943 } 944 } 945 return (n); 946 } 947 948 949 /* If we get here, then type != rr->type; if we have a handshake 950 * message, then it was unexpected (Hello Request or Client Hello). */ 951 952 { 953 /* 954 * In case of record types for which we have 'fragment' 955 * storage, * fill that so that we can process the data 956 * at a fixed place. 957 */ 958 unsigned int dest_maxlen = 0; 959 unsigned char *dest = NULL; 960 unsigned int *dest_len = NULL; 961 962 if (rr->type == SSL3_RT_HANDSHAKE) { 963 dest_maxlen = sizeof S3I(s)->handshake_fragment; 964 dest = S3I(s)->handshake_fragment; 965 dest_len = &S3I(s)->handshake_fragment_len; 966 } else if (rr->type == SSL3_RT_ALERT) { 967 dest_maxlen = sizeof S3I(s)->alert_fragment; 968 dest = S3I(s)->alert_fragment; 969 dest_len = &S3I(s)->alert_fragment_len; 970 } 971 if (dest_maxlen > 0) { 972 /* available space in 'dest' */ 973 n = dest_maxlen - *dest_len; 974 if (rr->length < n) 975 n = rr->length; /* available bytes */ 976 977 /* now move 'n' bytes: */ 978 while (n-- > 0) { 979 dest[(*dest_len)++] = rr->data[rr->off++]; 980 rr->length--; 981 } 982 983 if (*dest_len < dest_maxlen) 984 goto start; /* fragment was too small */ 985 } 986 } 987 988 /* S3I(s)->handshake_fragment_len == 4 iff rr->type == SSL3_RT_HANDSHAKE; 989 * S3I(s)->alert_fragment_len == 2 iff rr->type == SSL3_RT_ALERT. 990 * (Possibly rr is 'empty' now, i.e. rr->length may be 0.) */ 991 992 /* If we are a client, check for an incoming 'Hello Request': */ 993 if ((!s->server) && (S3I(s)->handshake_fragment_len >= 4) && 994 (S3I(s)->handshake_fragment[0] == SSL3_MT_HELLO_REQUEST) && 995 (s->session != NULL) && (s->session->cipher != NULL)) { 996 S3I(s)->handshake_fragment_len = 0; 997 998 if ((S3I(s)->handshake_fragment[1] != 0) || 999 (S3I(s)->handshake_fragment[2] != 0) || 1000 (S3I(s)->handshake_fragment[3] != 0)) { 1001 al = SSL_AD_DECODE_ERROR; 1002 SSLerror(s, SSL_R_BAD_HELLO_REQUEST); 1003 goto f_err; 1004 } 1005 1006 if (s->internal->msg_callback) 1007 s->internal->msg_callback(0, s->version, SSL3_RT_HANDSHAKE, 1008 S3I(s)->handshake_fragment, 4, s, 1009 s->internal->msg_callback_arg); 1010 1011 if (SSL_is_init_finished(s) && 1012 !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS) && 1013 !S3I(s)->renegotiate) { 1014 ssl3_renegotiate(s); 1015 if (ssl3_renegotiate_check(s)) { 1016 i = s->internal->handshake_func(s); 1017 if (i < 0) 1018 return (i); 1019 if (i == 0) { 1020 SSLerror(s, SSL_R_SSL_HANDSHAKE_FAILURE); 1021 return (-1); 1022 } 1023 1024 if (!(s->internal->mode & SSL_MODE_AUTO_RETRY)) { 1025 if (S3I(s)->rbuf.left == 0) { 1026 /* no read-ahead left? */ 1027 /* In the case where we try to read application data, 1028 * but we trigger an SSL handshake, we return -1 with 1029 * the retry option set. Otherwise renegotiation may 1030 * cause nasty problems in the blocking world */ 1031 ssl_force_want_read(s); 1032 return (-1); 1033 } 1034 } 1035 } 1036 } 1037 /* we either finished a handshake or ignored the request, 1038 * now try again to obtain the (application) data we were asked for */ 1039 goto start; 1040 } 1041 /* Disallow client initiated renegotiation if configured. */ 1042 if (s->server && SSL_is_init_finished(s) && 1043 S3I(s)->handshake_fragment_len >= 4 && 1044 S3I(s)->handshake_fragment[0] == SSL3_MT_CLIENT_HELLO && 1045 (s->internal->options & SSL_OP_NO_CLIENT_RENEGOTIATION)) { 1046 al = SSL_AD_NO_RENEGOTIATION; 1047 goto f_err; 1048 } 1049 /* If we are a server and get a client hello when renegotiation isn't 1050 * allowed send back a no renegotiation alert and carry on. 1051 * WARNING: experimental code, needs reviewing (steve) 1052 */ 1053 if (s->server && 1054 SSL_is_init_finished(s) && 1055 !S3I(s)->send_connection_binding && 1056 (S3I(s)->handshake_fragment_len >= 4) && 1057 (S3I(s)->handshake_fragment[0] == SSL3_MT_CLIENT_HELLO) && 1058 (s->session != NULL) && (s->session->cipher != NULL)) { 1059 /*S3I(s)->handshake_fragment_len = 0;*/ 1060 rr->length = 0; 1061 ssl3_send_alert(s, SSL3_AL_WARNING, SSL_AD_NO_RENEGOTIATION); 1062 goto start; 1063 } 1064 if (S3I(s)->alert_fragment_len >= 2) { 1065 int alert_level = S3I(s)->alert_fragment[0]; 1066 int alert_descr = S3I(s)->alert_fragment[1]; 1067 1068 S3I(s)->alert_fragment_len = 0; 1069 1070 if (s->internal->msg_callback) 1071 s->internal->msg_callback(0, s->version, SSL3_RT_ALERT, 1072 S3I(s)->alert_fragment, 2, s, s->internal->msg_callback_arg); 1073 1074 if (s->internal->info_callback != NULL) 1075 cb = s->internal->info_callback; 1076 else if (s->ctx->internal->info_callback != NULL) 1077 cb = s->ctx->internal->info_callback; 1078 1079 if (cb != NULL) { 1080 j = (alert_level << 8) | alert_descr; 1081 cb(s, SSL_CB_READ_ALERT, j); 1082 } 1083 1084 if (alert_level == SSL3_AL_WARNING) { 1085 S3I(s)->warn_alert = alert_descr; 1086 if (alert_descr == SSL_AD_CLOSE_NOTIFY) { 1087 s->internal->shutdown |= SSL_RECEIVED_SHUTDOWN; 1088 return (0); 1089 } 1090 /* This is a warning but we receive it if we requested 1091 * renegotiation and the peer denied it. Terminate with 1092 * a fatal alert because if application tried to 1093 * renegotiatie it presumably had a good reason and 1094 * expects it to succeed. 1095 * 1096 * In future we might have a renegotiation where we 1097 * don't care if the peer refused it where we carry on. 1098 */ 1099 else if (alert_descr == SSL_AD_NO_RENEGOTIATION) { 1100 al = SSL_AD_HANDSHAKE_FAILURE; 1101 SSLerror(s, SSL_R_NO_RENEGOTIATION); 1102 goto f_err; 1103 } 1104 } else if (alert_level == SSL3_AL_FATAL) { 1105 s->internal->rwstate = SSL_NOTHING; 1106 S3I(s)->fatal_alert = alert_descr; 1107 SSLerror(s, SSL_AD_REASON_OFFSET + alert_descr); 1108 ERR_asprintf_error_data("SSL alert number %d", 1109 alert_descr); 1110 s->internal->shutdown |= SSL_RECEIVED_SHUTDOWN; 1111 SSL_CTX_remove_session(s->ctx, s->session); 1112 return (0); 1113 } else { 1114 al = SSL_AD_ILLEGAL_PARAMETER; 1115 SSLerror(s, SSL_R_UNKNOWN_ALERT_TYPE); 1116 goto f_err; 1117 } 1118 1119 goto start; 1120 } 1121 1122 if (s->internal->shutdown & SSL_SENT_SHUTDOWN) { 1123 /* but we have not received a shutdown */ 1124 s->internal->rwstate = SSL_NOTHING; 1125 rr->length = 0; 1126 return (0); 1127 } 1128 1129 if (rr->type == SSL3_RT_CHANGE_CIPHER_SPEC) { 1130 /* 'Change Cipher Spec' is just a single byte, so we know 1131 * exactly what the record payload has to look like */ 1132 if ((rr->length != 1) || (rr->off != 0) || 1133 (rr->data[0] != SSL3_MT_CCS)) { 1134 al = SSL_AD_ILLEGAL_PARAMETER; 1135 SSLerror(s, SSL_R_BAD_CHANGE_CIPHER_SPEC); 1136 goto f_err; 1137 } 1138 1139 /* Check we have a cipher to change to */ 1140 if (S3I(s)->hs.new_cipher == NULL) { 1141 al = SSL_AD_UNEXPECTED_MESSAGE; 1142 SSLerror(s, SSL_R_CCS_RECEIVED_EARLY); 1143 goto f_err; 1144 } 1145 1146 /* Check that we should be receiving a Change Cipher Spec. */ 1147 if (!(s->s3->flags & SSL3_FLAGS_CCS_OK)) { 1148 al = SSL_AD_UNEXPECTED_MESSAGE; 1149 SSLerror(s, SSL_R_CCS_RECEIVED_EARLY); 1150 goto f_err; 1151 } 1152 s->s3->flags &= ~SSL3_FLAGS_CCS_OK; 1153 1154 rr->length = 0; 1155 1156 if (s->internal->msg_callback) { 1157 s->internal->msg_callback(0, s->version, 1158 SSL3_RT_CHANGE_CIPHER_SPEC, rr->data, 1, s, 1159 s->internal->msg_callback_arg); 1160 } 1161 1162 S3I(s)->change_cipher_spec = 1; 1163 if (!ssl3_do_change_cipher_spec(s)) 1164 goto err; 1165 else 1166 goto start; 1167 } 1168 1169 /* Unexpected handshake message (Client Hello, or protocol violation) */ 1170 if ((S3I(s)->handshake_fragment_len >= 4) && !s->internal->in_handshake) { 1171 if (((S3I(s)->hs.state&SSL_ST_MASK) == SSL_ST_OK) && 1172 !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS)) { 1173 S3I(s)->hs.state = s->server ? SSL_ST_ACCEPT : SSL_ST_CONNECT; 1174 s->internal->renegotiate = 1; 1175 s->internal->new_session = 1; 1176 } 1177 i = s->internal->handshake_func(s); 1178 if (i < 0) 1179 return (i); 1180 if (i == 0) { 1181 SSLerror(s, SSL_R_SSL_HANDSHAKE_FAILURE); 1182 return (-1); 1183 } 1184 1185 if (!(s->internal->mode & SSL_MODE_AUTO_RETRY)) { 1186 if (S3I(s)->rbuf.left == 0) { /* no read-ahead left? */ 1187 /* In the case where we try to read application data, 1188 * but we trigger an SSL handshake, we return -1 with 1189 * the retry option set. Otherwise renegotiation may 1190 * cause nasty problems in the blocking world */ 1191 ssl_force_want_read(s); 1192 return (-1); 1193 } 1194 } 1195 goto start; 1196 } 1197 1198 switch (rr->type) { 1199 default: 1200 /* 1201 * TLS up to v1.1 just ignores unknown message types: 1202 * TLS v1.2 give an unexpected message alert. 1203 */ 1204 if (s->version >= TLS1_VERSION && 1205 s->version <= TLS1_1_VERSION) { 1206 rr->length = 0; 1207 goto start; 1208 } 1209 al = SSL_AD_UNEXPECTED_MESSAGE; 1210 SSLerror(s, SSL_R_UNEXPECTED_RECORD); 1211 goto f_err; 1212 case SSL3_RT_CHANGE_CIPHER_SPEC: 1213 case SSL3_RT_ALERT: 1214 case SSL3_RT_HANDSHAKE: 1215 /* we already handled all of these, with the possible exception 1216 * of SSL3_RT_HANDSHAKE when s->internal->in_handshake is set, but that 1217 * should not happen when type != rr->type */ 1218 al = SSL_AD_UNEXPECTED_MESSAGE; 1219 SSLerror(s, ERR_R_INTERNAL_ERROR); 1220 goto f_err; 1221 case SSL3_RT_APPLICATION_DATA: 1222 /* At this point, we were expecting handshake data, 1223 * but have application data. If the library was 1224 * running inside ssl3_read() (i.e. in_read_app_data 1225 * is set) and it makes sense to read application data 1226 * at this point (session renegotiation not yet started), 1227 * we will indulge it. 1228 */ 1229 if (S3I(s)->in_read_app_data && 1230 (S3I(s)->total_renegotiations != 0) && 1231 (((S3I(s)->hs.state & SSL_ST_CONNECT) && 1232 (S3I(s)->hs.state >= SSL3_ST_CW_CLNT_HELLO_A) && 1233 (S3I(s)->hs.state <= SSL3_ST_CR_SRVR_HELLO_A)) || 1234 ((S3I(s)->hs.state & SSL_ST_ACCEPT) && 1235 (S3I(s)->hs.state <= SSL3_ST_SW_HELLO_REQ_A) && 1236 (S3I(s)->hs.state >= SSL3_ST_SR_CLNT_HELLO_A)))) { 1237 S3I(s)->in_read_app_data = 2; 1238 return (-1); 1239 } else { 1240 al = SSL_AD_UNEXPECTED_MESSAGE; 1241 SSLerror(s, SSL_R_UNEXPECTED_RECORD); 1242 goto f_err; 1243 } 1244 } 1245 /* not reached */ 1246 1247 f_err: 1248 ssl3_send_alert(s, SSL3_AL_FATAL, al); 1249 err: 1250 return (-1); 1251 } 1252 1253 int 1254 ssl3_do_change_cipher_spec(SSL *s) 1255 { 1256 int i; 1257 const char *sender; 1258 int slen; 1259 1260 if (S3I(s)->hs.state & SSL_ST_ACCEPT) 1261 i = SSL3_CHANGE_CIPHER_SERVER_READ; 1262 else 1263 i = SSL3_CHANGE_CIPHER_CLIENT_READ; 1264 1265 if (S3I(s)->hs.key_block == NULL) { 1266 if (s->session == NULL || s->session->master_key_length == 0) { 1267 /* might happen if dtls1_read_bytes() calls this */ 1268 SSLerror(s, SSL_R_CCS_RECEIVED_EARLY); 1269 return (0); 1270 } 1271 1272 s->session->cipher = S3I(s)->hs.new_cipher; 1273 if (!tls1_setup_key_block(s)) 1274 return (0); 1275 } 1276 1277 if (!tls1_change_cipher_state(s, i)) 1278 return (0); 1279 1280 /* we have to record the message digest at 1281 * this point so we can get it before we read 1282 * the finished message */ 1283 if (S3I(s)->hs.state & SSL_ST_CONNECT) { 1284 sender = TLS_MD_SERVER_FINISH_CONST; 1285 slen = TLS_MD_SERVER_FINISH_CONST_SIZE; 1286 } else { 1287 sender = TLS_MD_CLIENT_FINISH_CONST; 1288 slen = TLS_MD_CLIENT_FINISH_CONST_SIZE; 1289 } 1290 1291 i = tls1_final_finish_mac(s, sender, slen, 1292 S3I(s)->tmp.peer_finish_md); 1293 if (i == 0) { 1294 SSLerror(s, ERR_R_INTERNAL_ERROR); 1295 return 0; 1296 } 1297 S3I(s)->tmp.peer_finish_md_len = i; 1298 1299 return (1); 1300 } 1301 1302 int 1303 ssl3_send_alert(SSL *s, int level, int desc) 1304 { 1305 /* Map tls/ssl alert value to correct one */ 1306 desc = tls1_alert_code(desc); 1307 if (desc < 0) 1308 return -1; 1309 /* If a fatal one, remove from cache */ 1310 if ((level == 2) && (s->session != NULL)) 1311 SSL_CTX_remove_session(s->ctx, s->session); 1312 1313 S3I(s)->alert_dispatch = 1; 1314 S3I(s)->send_alert[0] = level; 1315 S3I(s)->send_alert[1] = desc; 1316 if (S3I(s)->wbuf.left == 0) /* data still being written out? */ 1317 return s->method->ssl_dispatch_alert(s); 1318 1319 /* else data is still being written out, we will get written 1320 * some time in the future */ 1321 return -1; 1322 } 1323 1324 int 1325 ssl3_dispatch_alert(SSL *s) 1326 { 1327 int i, j; 1328 void (*cb)(const SSL *ssl, int type, int val) = NULL; 1329 1330 S3I(s)->alert_dispatch = 0; 1331 i = do_ssl3_write(s, SSL3_RT_ALERT, &S3I(s)->send_alert[0], 2); 1332 if (i <= 0) { 1333 S3I(s)->alert_dispatch = 1; 1334 } else { 1335 /* Alert sent to BIO. If it is important, flush it now. 1336 * If the message does not get sent due to non-blocking IO, 1337 * we will not worry too much. */ 1338 if (S3I(s)->send_alert[0] == SSL3_AL_FATAL) 1339 (void)BIO_flush(s->wbio); 1340 1341 if (s->internal->msg_callback) 1342 s->internal->msg_callback(1, s->version, SSL3_RT_ALERT, 1343 S3I(s)->send_alert, 2, s, s->internal->msg_callback_arg); 1344 1345 if (s->internal->info_callback != NULL) 1346 cb = s->internal->info_callback; 1347 else if (s->ctx->internal->info_callback != NULL) 1348 cb = s->ctx->internal->info_callback; 1349 1350 if (cb != NULL) { 1351 j = (S3I(s)->send_alert[0]<<8)|S3I(s)->send_alert[1]; 1352 cb(s, SSL_CB_WRITE_ALERT, j); 1353 } 1354 } 1355 return (i); 1356 } 1357