1 /* $OpenBSD: ssl_pkt.c,v 1.24 2020/03/16 15:25:14 tb 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 ssl3_create_record(SSL *s, unsigned char *p, int type, const unsigned char *buf, 621 unsigned int len) 622 { 623 SSL3_RECORD_INTERNAL *wr = &(S3I(s)->wrec); 624 SSL_SESSION *sess = s->session; 625 int eivlen, mac_size; 626 uint16_t version; 627 CBB cbb; 628 629 memset(&cbb, 0, sizeof(cbb)); 630 631 if ((sess == NULL) || (s->internal->enc_write_ctx == NULL) || 632 (EVP_MD_CTX_md(s->internal->write_hash) == NULL)) { 633 mac_size = 0; 634 } else { 635 mac_size = EVP_MD_CTX_size(s->internal->write_hash); 636 if (mac_size < 0) 637 goto err; 638 } 639 640 /* 641 * Some servers hang if initial client hello is larger than 256 642 * bytes and record version number > TLS 1.0. 643 */ 644 version = s->version; 645 if (S3I(s)->hs.state == SSL3_ST_CW_CLNT_HELLO_B && !s->internal->renegotiate && 646 TLS1_get_version(s) > TLS1_VERSION) 647 version = TLS1_VERSION; 648 649 if (!CBB_init_fixed(&cbb, p, SSL3_RT_HEADER_LENGTH)) 650 goto err; 651 652 /* Write the header. */ 653 if (!CBB_add_u8(&cbb, type)) 654 goto err; 655 if (!CBB_add_u16(&cbb, version)) 656 goto err; 657 658 p += SSL3_RT_HEADER_LENGTH; 659 660 /* Explicit IV length. */ 661 eivlen = 0; 662 if (s->internal->enc_write_ctx && SSL_USE_EXPLICIT_IV(s)) { 663 int mode = EVP_CIPHER_CTX_mode(s->internal->enc_write_ctx); 664 if (mode == EVP_CIPH_CBC_MODE) { 665 eivlen = EVP_CIPHER_CTX_iv_length(s->internal->enc_write_ctx); 666 if (eivlen <= 1) 667 eivlen = 0; 668 } 669 } else if (s->internal->aead_write_ctx != NULL && 670 s->internal->aead_write_ctx->variable_nonce_in_record) { 671 eivlen = s->internal->aead_write_ctx->variable_nonce_len; 672 } 673 674 /* lets setup the record stuff. */ 675 wr->type = type; 676 wr->data = p + eivlen; 677 wr->length = (int)len; 678 wr->input = (unsigned char *)buf; 679 680 /* we now 'read' from wr->input, wr->length bytes into wr->data */ 681 682 memcpy(wr->data, wr->input, wr->length); 683 wr->input = wr->data; 684 685 /* we should still have the output to wr->data and the input 686 * from wr->input. Length should be wr->length. 687 * wr->data still points in the wb->buf */ 688 689 if (mac_size != 0) { 690 if (tls1_mac(s, &(p[wr->length + eivlen]), 1) < 0) 691 goto err; 692 wr->length += mac_size; 693 } 694 695 wr->input = p; 696 wr->data = p; 697 698 if (eivlen) { 699 /* if (RAND_pseudo_bytes(p, eivlen) <= 0) 700 goto err; 701 */ 702 wr->length += eivlen; 703 } 704 705 /* tls1_enc can only have an error on read */ 706 tls1_enc(s, 1); 707 708 /* record length after mac and block padding */ 709 if (!CBB_add_u16(&cbb, wr->length)) 710 goto err; 711 if (!CBB_finish(&cbb, NULL, NULL)) 712 goto err; 713 714 /* we should now have 715 * wr->data pointing to the encrypted data, which is 716 * wr->length long */ 717 wr->type = type; /* not needed but helps for debugging */ 718 wr->length += SSL3_RT_HEADER_LENGTH; 719 720 return 1; 721 722 err: 723 CBB_cleanup(&cbb); 724 725 return 0; 726 } 727 728 static int 729 do_ssl3_write(SSL *s, int type, const unsigned char *buf, unsigned int len) 730 { 731 SSL3_RECORD_INTERNAL *wr = &(S3I(s)->wrec); 732 SSL3_BUFFER_INTERNAL *wb = &(S3I(s)->wbuf); 733 SSL_SESSION *sess = s->session; 734 unsigned char *p; 735 int i, clear = 0; 736 int prefix_len = 0; 737 size_t align; 738 739 if (wb->buf == NULL) 740 if (!ssl3_setup_write_buffer(s)) 741 return -1; 742 743 /* first check if there is a SSL3_BUFFER_INTERNAL still being written 744 * out. This will happen with non blocking IO */ 745 if (wb->left != 0) 746 return (ssl3_write_pending(s, type, buf, len)); 747 748 /* If we have an alert to send, lets send it */ 749 if (S3I(s)->alert_dispatch) { 750 i = s->method->ssl_dispatch_alert(s); 751 if (i <= 0) 752 return (i); 753 /* if it went, fall through and send more stuff */ 754 /* we may have released our buffer, so get it again */ 755 if (wb->buf == NULL) 756 if (!ssl3_setup_write_buffer(s)) 757 return -1; 758 } 759 760 if (len == 0) 761 return 0; 762 763 align = (size_t)wb->buf + SSL3_RT_HEADER_LENGTH; 764 align = (-align) & (SSL3_ALIGN_PAYLOAD - 1); 765 766 p = wb->buf + align; 767 wb->offset = align; 768 769 if ((sess == NULL) || (s->internal->enc_write_ctx == NULL) || 770 (EVP_MD_CTX_md(s->internal->write_hash) == NULL)) { 771 clear = s->internal->enc_write_ctx ? 0 : 1; /* must be AEAD cipher */ 772 } 773 774 if (!clear && !S3I(s)->empty_fragment_done) { 775 /* 776 * Countermeasure against known-IV weakness in CBC ciphersuites 777 * (see http://www.openssl.org/~bodo/tls-cbc.txt) 778 */ 779 if (S3I(s)->need_empty_fragments && 780 type == SSL3_RT_APPLICATION_DATA) { 781 /* extra fragment would be couple of cipher blocks, 782 * which would be multiple of SSL3_ALIGN_PAYLOAD, so 783 * if we want to align the real payload, then we can 784 * just pretent we simply have two headers. */ 785 align = (size_t)wb->buf + 2 * SSL3_RT_HEADER_LENGTH; 786 align = (-align) & (SSL3_ALIGN_PAYLOAD - 1); 787 788 p = wb->buf + align; 789 wb->offset = align; 790 791 if (!ssl3_create_record(s, p, type, buf, 0)) 792 goto err; 793 794 prefix_len = wr->length; 795 if (prefix_len > (SSL3_RT_HEADER_LENGTH + 796 SSL3_RT_SEND_MAX_ENCRYPTED_OVERHEAD)) { 797 /* insufficient space */ 798 SSLerror(s, ERR_R_INTERNAL_ERROR); 799 goto err; 800 } 801 802 p = wb->buf + wb->offset + prefix_len; 803 } 804 805 S3I(s)->empty_fragment_done = 1; 806 } 807 808 if (!ssl3_create_record(s, p, type, buf, len)) 809 goto err; 810 811 /* now let's set up wb */ 812 wb->left = prefix_len + wr->length; 813 814 /* memorize arguments so that ssl3_write_pending can detect 815 * bad write retries later */ 816 S3I(s)->wpend_tot = len; 817 S3I(s)->wpend_buf = buf; 818 S3I(s)->wpend_type = type; 819 S3I(s)->wpend_ret = len; 820 821 /* we now just need to write the buffer */ 822 return ssl3_write_pending(s, type, buf, len); 823 err: 824 return -1; 825 } 826 827 /* if S3I(s)->wbuf.left != 0, we need to call this */ 828 int 829 ssl3_write_pending(SSL *s, int type, const unsigned char *buf, unsigned int len) 830 { 831 int i; 832 SSL3_BUFFER_INTERNAL *wb = &(S3I(s)->wbuf); 833 834 /* XXXX */ 835 if ((S3I(s)->wpend_tot > (int)len) || ((S3I(s)->wpend_buf != buf) && 836 !(s->internal->mode & SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER)) || 837 (S3I(s)->wpend_type != type)) { 838 SSLerror(s, SSL_R_BAD_WRITE_RETRY); 839 return (-1); 840 } 841 842 for (;;) { 843 errno = 0; 844 if (s->wbio != NULL) { 845 s->internal->rwstate = SSL_WRITING; 846 i = BIO_write(s->wbio, 847 (char *)&(wb->buf[wb->offset]), 848 (unsigned int)wb->left); 849 } else { 850 SSLerror(s, SSL_R_BIO_NOT_SET); 851 i = -1; 852 } 853 if (i == wb->left) { 854 wb->left = 0; 855 wb->offset += i; 856 if (s->internal->mode & SSL_MODE_RELEASE_BUFFERS && 857 !SSL_IS_DTLS(s)) 858 ssl3_release_write_buffer(s); 859 s->internal->rwstate = SSL_NOTHING; 860 return (S3I(s)->wpend_ret); 861 } else if (i <= 0) { 862 /* 863 * For DTLS, just drop it. That's kind of the 864 * whole point in using a datagram service. 865 */ 866 if (SSL_IS_DTLS(s)) 867 wb->left = 0; 868 return (i); 869 } 870 wb->offset += i; 871 wb->left -= i; 872 } 873 } 874 875 /* Return up to 'len' payload bytes received in 'type' records. 876 * 'type' is one of the following: 877 * 878 * - SSL3_RT_HANDSHAKE (when ssl3_get_message calls us) 879 * - SSL3_RT_APPLICATION_DATA (when ssl3_read calls us) 880 * - 0 (during a shutdown, no data has to be returned) 881 * 882 * If we don't have stored data to work from, read a SSL/TLS record first 883 * (possibly multiple records if we still don't have anything to return). 884 * 885 * This function must handle any surprises the peer may have for us, such as 886 * Alert records (e.g. close_notify), ChangeCipherSpec records (not really 887 * a surprise, but handled as if it were), or renegotiation requests. 888 * Also if record payloads contain fragments too small to process, we store 889 * them until there is enough for the respective protocol (the record protocol 890 * may use arbitrary fragmentation and even interleaving): 891 * Change cipher spec protocol 892 * just 1 byte needed, no need for keeping anything stored 893 * Alert protocol 894 * 2 bytes needed (AlertLevel, AlertDescription) 895 * Handshake protocol 896 * 4 bytes needed (HandshakeType, uint24 length) -- we just have 897 * to detect unexpected Client Hello and Hello Request messages 898 * here, anything else is handled by higher layers 899 * Application data protocol 900 * none of our business 901 */ 902 int 903 ssl3_read_bytes(SSL *s, int type, unsigned char *buf, int len, int peek) 904 { 905 void (*cb)(const SSL *ssl, int type2, int val) = NULL; 906 int al, i, j, ret, rrcount = 0; 907 unsigned int n; 908 SSL3_RECORD_INTERNAL *rr; 909 910 if (S3I(s)->rbuf.buf == NULL) /* Not initialized yet */ 911 if (!ssl3_setup_read_buffer(s)) 912 return (-1); 913 914 if (len < 0) { 915 SSLerror(s, ERR_R_INTERNAL_ERROR); 916 return -1; 917 } 918 919 if ((type && type != SSL3_RT_APPLICATION_DATA && 920 type != SSL3_RT_HANDSHAKE) || 921 (peek && (type != SSL3_RT_APPLICATION_DATA))) { 922 SSLerror(s, ERR_R_INTERNAL_ERROR); 923 return -1; 924 } 925 926 if ((type == SSL3_RT_HANDSHAKE) && 927 (S3I(s)->handshake_fragment_len > 0)) { 928 /* (partially) satisfy request from storage */ 929 unsigned char *src = S3I(s)->handshake_fragment; 930 unsigned char *dst = buf; 931 unsigned int k; 932 933 /* peek == 0 */ 934 n = 0; 935 while ((len > 0) && (S3I(s)->handshake_fragment_len > 0)) { 936 *dst++ = *src++; 937 len--; 938 S3I(s)->handshake_fragment_len--; 939 n++; 940 } 941 /* move any remaining fragment bytes: */ 942 for (k = 0; k < S3I(s)->handshake_fragment_len; k++) 943 S3I(s)->handshake_fragment[k] = *src++; 944 return n; 945 } 946 947 /* 948 * Now S3I(s)->handshake_fragment_len == 0 if 949 * type == SSL3_RT_HANDSHAKE. 950 */ 951 if (!s->internal->in_handshake && SSL_in_init(s)) { 952 /* type == SSL3_RT_APPLICATION_DATA */ 953 i = s->internal->handshake_func(s); 954 if (i < 0) 955 return (i); 956 if (i == 0) { 957 SSLerror(s, SSL_R_SSL_HANDSHAKE_FAILURE); 958 return (-1); 959 } 960 } 961 962 start: 963 /* 964 * Do not process more than three consecutive records, otherwise the 965 * peer can cause us to loop indefinitely. Instead, return with an 966 * SSL_ERROR_WANT_READ so the caller can choose when to handle further 967 * processing. In the future, the total number of non-handshake and 968 * non-application data records per connection should probably also be 969 * limited... 970 */ 971 if (rrcount++ >= 3) { 972 ssl_force_want_read(s); 973 return -1; 974 } 975 976 s->internal->rwstate = SSL_NOTHING; 977 978 /* 979 * S3I(s)->rrec.type - is the type of record 980 * S3I(s)->rrec.data, - data 981 * S3I(s)->rrec.off, - offset into 'data' for next read 982 * S3I(s)->rrec.length, - number of bytes. 983 */ 984 rr = &(S3I(s)->rrec); 985 986 /* get new packet if necessary */ 987 if ((rr->length == 0) || (s->internal->rstate == SSL_ST_READ_BODY)) { 988 ret = ssl3_get_record(s); 989 if (ret <= 0) 990 return (ret); 991 } 992 993 /* we now have a packet which can be read and processed */ 994 995 if (S3I(s)->change_cipher_spec /* set when we receive ChangeCipherSpec, 996 * reset by ssl3_get_finished */ 997 && (rr->type != SSL3_RT_HANDSHAKE)) { 998 al = SSL_AD_UNEXPECTED_MESSAGE; 999 SSLerror(s, SSL_R_DATA_BETWEEN_CCS_AND_FINISHED); 1000 goto f_err; 1001 } 1002 1003 /* If the other end has shut down, throw anything we read away 1004 * (even in 'peek' mode) */ 1005 if (s->internal->shutdown & SSL_RECEIVED_SHUTDOWN) { 1006 rr->length = 0; 1007 s->internal->rwstate = SSL_NOTHING; 1008 return (0); 1009 } 1010 1011 1012 /* SSL3_RT_APPLICATION_DATA or SSL3_RT_HANDSHAKE */ 1013 if (type == rr->type) { 1014 /* make sure that we are not getting application data when we 1015 * are doing a handshake for the first time */ 1016 if (SSL_in_init(s) && (type == SSL3_RT_APPLICATION_DATA) && 1017 (s->enc_read_ctx == NULL)) { 1018 al = SSL_AD_UNEXPECTED_MESSAGE; 1019 SSLerror(s, SSL_R_APP_DATA_IN_HANDSHAKE); 1020 goto f_err; 1021 } 1022 1023 if (len <= 0) 1024 return (len); 1025 1026 if ((unsigned int)len > rr->length) 1027 n = rr->length; 1028 else 1029 n = (unsigned int)len; 1030 1031 memcpy(buf, &(rr->data[rr->off]), n); 1032 if (!peek) { 1033 memset(&(rr->data[rr->off]), 0, n); 1034 rr->length -= n; 1035 rr->off += n; 1036 if (rr->length == 0) { 1037 s->internal->rstate = SSL_ST_READ_HEADER; 1038 rr->off = 0; 1039 if (s->internal->mode & SSL_MODE_RELEASE_BUFFERS && 1040 S3I(s)->rbuf.left == 0) 1041 ssl3_release_read_buffer(s); 1042 } 1043 } 1044 return (n); 1045 } 1046 1047 1048 /* If we get here, then type != rr->type; if we have a handshake 1049 * message, then it was unexpected (Hello Request or Client Hello). */ 1050 1051 { 1052 /* 1053 * In case of record types for which we have 'fragment' 1054 * storage, * fill that so that we can process the data 1055 * at a fixed place. 1056 */ 1057 unsigned int dest_maxlen = 0; 1058 unsigned char *dest = NULL; 1059 unsigned int *dest_len = NULL; 1060 1061 if (rr->type == SSL3_RT_HANDSHAKE) { 1062 dest_maxlen = sizeof S3I(s)->handshake_fragment; 1063 dest = S3I(s)->handshake_fragment; 1064 dest_len = &S3I(s)->handshake_fragment_len; 1065 } else if (rr->type == SSL3_RT_ALERT) { 1066 dest_maxlen = sizeof S3I(s)->alert_fragment; 1067 dest = S3I(s)->alert_fragment; 1068 dest_len = &S3I(s)->alert_fragment_len; 1069 } 1070 if (dest_maxlen > 0) { 1071 /* available space in 'dest' */ 1072 n = dest_maxlen - *dest_len; 1073 if (rr->length < n) 1074 n = rr->length; /* available bytes */ 1075 1076 /* now move 'n' bytes: */ 1077 while (n-- > 0) { 1078 dest[(*dest_len)++] = rr->data[rr->off++]; 1079 rr->length--; 1080 } 1081 1082 if (*dest_len < dest_maxlen) 1083 goto start; /* fragment was too small */ 1084 } 1085 } 1086 1087 /* S3I(s)->handshake_fragment_len == 4 iff rr->type == SSL3_RT_HANDSHAKE; 1088 * S3I(s)->alert_fragment_len == 2 iff rr->type == SSL3_RT_ALERT. 1089 * (Possibly rr is 'empty' now, i.e. rr->length may be 0.) */ 1090 1091 /* If we are a client, check for an incoming 'Hello Request': */ 1092 if ((!s->server) && (S3I(s)->handshake_fragment_len >= 4) && 1093 (S3I(s)->handshake_fragment[0] == SSL3_MT_HELLO_REQUEST) && 1094 (s->session != NULL) && (s->session->cipher != NULL)) { 1095 S3I(s)->handshake_fragment_len = 0; 1096 1097 if ((S3I(s)->handshake_fragment[1] != 0) || 1098 (S3I(s)->handshake_fragment[2] != 0) || 1099 (S3I(s)->handshake_fragment[3] != 0)) { 1100 al = SSL_AD_DECODE_ERROR; 1101 SSLerror(s, SSL_R_BAD_HELLO_REQUEST); 1102 goto f_err; 1103 } 1104 1105 if (s->internal->msg_callback) 1106 s->internal->msg_callback(0, s->version, SSL3_RT_HANDSHAKE, 1107 S3I(s)->handshake_fragment, 4, s, 1108 s->internal->msg_callback_arg); 1109 1110 if (SSL_is_init_finished(s) && 1111 !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS) && 1112 !S3I(s)->renegotiate) { 1113 ssl3_renegotiate(s); 1114 if (ssl3_renegotiate_check(s)) { 1115 i = s->internal->handshake_func(s); 1116 if (i < 0) 1117 return (i); 1118 if (i == 0) { 1119 SSLerror(s, SSL_R_SSL_HANDSHAKE_FAILURE); 1120 return (-1); 1121 } 1122 1123 if (!(s->internal->mode & SSL_MODE_AUTO_RETRY)) { 1124 if (S3I(s)->rbuf.left == 0) { 1125 /* no read-ahead left? */ 1126 /* In the case where we try to read application data, 1127 * but we trigger an SSL handshake, we return -1 with 1128 * the retry option set. Otherwise renegotiation may 1129 * cause nasty problems in the blocking world */ 1130 ssl_force_want_read(s); 1131 return (-1); 1132 } 1133 } 1134 } 1135 } 1136 /* we either finished a handshake or ignored the request, 1137 * now try again to obtain the (application) data we were asked for */ 1138 goto start; 1139 } 1140 /* Disallow client initiated renegotiation if configured. */ 1141 if (s->server && SSL_is_init_finished(s) && 1142 S3I(s)->handshake_fragment_len >= 4 && 1143 S3I(s)->handshake_fragment[0] == SSL3_MT_CLIENT_HELLO && 1144 (s->internal->options & SSL_OP_NO_CLIENT_RENEGOTIATION)) { 1145 al = SSL_AD_NO_RENEGOTIATION; 1146 goto f_err; 1147 } 1148 /* If we are a server and get a client hello when renegotiation isn't 1149 * allowed send back a no renegotiation alert and carry on. 1150 * WARNING: experimental code, needs reviewing (steve) 1151 */ 1152 if (s->server && 1153 SSL_is_init_finished(s) && 1154 !S3I(s)->send_connection_binding && 1155 (S3I(s)->handshake_fragment_len >= 4) && 1156 (S3I(s)->handshake_fragment[0] == SSL3_MT_CLIENT_HELLO) && 1157 (s->session != NULL) && (s->session->cipher != NULL)) { 1158 /*S3I(s)->handshake_fragment_len = 0;*/ 1159 rr->length = 0; 1160 ssl3_send_alert(s, SSL3_AL_WARNING, SSL_AD_NO_RENEGOTIATION); 1161 goto start; 1162 } 1163 if (S3I(s)->alert_fragment_len >= 2) { 1164 int alert_level = S3I(s)->alert_fragment[0]; 1165 int alert_descr = S3I(s)->alert_fragment[1]; 1166 1167 S3I(s)->alert_fragment_len = 0; 1168 1169 if (s->internal->msg_callback) 1170 s->internal->msg_callback(0, s->version, SSL3_RT_ALERT, 1171 S3I(s)->alert_fragment, 2, s, s->internal->msg_callback_arg); 1172 1173 if (s->internal->info_callback != NULL) 1174 cb = s->internal->info_callback; 1175 else if (s->ctx->internal->info_callback != NULL) 1176 cb = s->ctx->internal->info_callback; 1177 1178 if (cb != NULL) { 1179 j = (alert_level << 8) | alert_descr; 1180 cb(s, SSL_CB_READ_ALERT, j); 1181 } 1182 1183 if (alert_level == SSL3_AL_WARNING) { 1184 S3I(s)->warn_alert = alert_descr; 1185 if (alert_descr == SSL_AD_CLOSE_NOTIFY) { 1186 s->internal->shutdown |= SSL_RECEIVED_SHUTDOWN; 1187 return (0); 1188 } 1189 /* This is a warning but we receive it if we requested 1190 * renegotiation and the peer denied it. Terminate with 1191 * a fatal alert because if application tried to 1192 * renegotiatie it presumably had a good reason and 1193 * expects it to succeed. 1194 * 1195 * In future we might have a renegotiation where we 1196 * don't care if the peer refused it where we carry on. 1197 */ 1198 else if (alert_descr == SSL_AD_NO_RENEGOTIATION) { 1199 al = SSL_AD_HANDSHAKE_FAILURE; 1200 SSLerror(s, SSL_R_NO_RENEGOTIATION); 1201 goto f_err; 1202 } 1203 } else if (alert_level == SSL3_AL_FATAL) { 1204 s->internal->rwstate = SSL_NOTHING; 1205 S3I(s)->fatal_alert = alert_descr; 1206 SSLerror(s, SSL_AD_REASON_OFFSET + alert_descr); 1207 ERR_asprintf_error_data("SSL alert number %d", 1208 alert_descr); 1209 s->internal->shutdown |= SSL_RECEIVED_SHUTDOWN; 1210 SSL_CTX_remove_session(s->ctx, s->session); 1211 return (0); 1212 } else { 1213 al = SSL_AD_ILLEGAL_PARAMETER; 1214 SSLerror(s, SSL_R_UNKNOWN_ALERT_TYPE); 1215 goto f_err; 1216 } 1217 1218 goto start; 1219 } 1220 1221 if (s->internal->shutdown & SSL_SENT_SHUTDOWN) { 1222 /* but we have not received a shutdown */ 1223 s->internal->rwstate = SSL_NOTHING; 1224 rr->length = 0; 1225 return (0); 1226 } 1227 1228 if (rr->type == SSL3_RT_CHANGE_CIPHER_SPEC) { 1229 /* 'Change Cipher Spec' is just a single byte, so we know 1230 * exactly what the record payload has to look like */ 1231 if ((rr->length != 1) || (rr->off != 0) || 1232 (rr->data[0] != SSL3_MT_CCS)) { 1233 al = SSL_AD_ILLEGAL_PARAMETER; 1234 SSLerror(s, SSL_R_BAD_CHANGE_CIPHER_SPEC); 1235 goto f_err; 1236 } 1237 1238 /* Check we have a cipher to change to */ 1239 if (S3I(s)->hs.new_cipher == NULL) { 1240 al = SSL_AD_UNEXPECTED_MESSAGE; 1241 SSLerror(s, SSL_R_CCS_RECEIVED_EARLY); 1242 goto f_err; 1243 } 1244 1245 /* Check that we should be receiving a Change Cipher Spec. */ 1246 if (!(s->s3->flags & SSL3_FLAGS_CCS_OK)) { 1247 al = SSL_AD_UNEXPECTED_MESSAGE; 1248 SSLerror(s, SSL_R_CCS_RECEIVED_EARLY); 1249 goto f_err; 1250 } 1251 s->s3->flags &= ~SSL3_FLAGS_CCS_OK; 1252 1253 rr->length = 0; 1254 1255 if (s->internal->msg_callback) { 1256 s->internal->msg_callback(0, s->version, 1257 SSL3_RT_CHANGE_CIPHER_SPEC, rr->data, 1, s, 1258 s->internal->msg_callback_arg); 1259 } 1260 1261 S3I(s)->change_cipher_spec = 1; 1262 if (!ssl3_do_change_cipher_spec(s)) 1263 goto err; 1264 else 1265 goto start; 1266 } 1267 1268 /* Unexpected handshake message (Client Hello, or protocol violation) */ 1269 if ((S3I(s)->handshake_fragment_len >= 4) && !s->internal->in_handshake) { 1270 if (((S3I(s)->hs.state&SSL_ST_MASK) == SSL_ST_OK) && 1271 !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS)) { 1272 S3I(s)->hs.state = s->server ? SSL_ST_ACCEPT : SSL_ST_CONNECT; 1273 s->internal->renegotiate = 1; 1274 s->internal->new_session = 1; 1275 } 1276 i = s->internal->handshake_func(s); 1277 if (i < 0) 1278 return (i); 1279 if (i == 0) { 1280 SSLerror(s, SSL_R_SSL_HANDSHAKE_FAILURE); 1281 return (-1); 1282 } 1283 1284 if (!(s->internal->mode & SSL_MODE_AUTO_RETRY)) { 1285 if (S3I(s)->rbuf.left == 0) { /* no read-ahead left? */ 1286 /* In the case where we try to read application data, 1287 * but we trigger an SSL handshake, we return -1 with 1288 * the retry option set. Otherwise renegotiation may 1289 * cause nasty problems in the blocking world */ 1290 ssl_force_want_read(s); 1291 return (-1); 1292 } 1293 } 1294 goto start; 1295 } 1296 1297 switch (rr->type) { 1298 default: 1299 /* 1300 * TLS up to v1.1 just ignores unknown message types: 1301 * TLS v1.2 give an unexpected message alert. 1302 */ 1303 if (s->version >= TLS1_VERSION && 1304 s->version <= TLS1_1_VERSION) { 1305 rr->length = 0; 1306 goto start; 1307 } 1308 al = SSL_AD_UNEXPECTED_MESSAGE; 1309 SSLerror(s, SSL_R_UNEXPECTED_RECORD); 1310 goto f_err; 1311 case SSL3_RT_CHANGE_CIPHER_SPEC: 1312 case SSL3_RT_ALERT: 1313 case SSL3_RT_HANDSHAKE: 1314 /* we already handled all of these, with the possible exception 1315 * of SSL3_RT_HANDSHAKE when s->internal->in_handshake is set, but that 1316 * should not happen when type != rr->type */ 1317 al = SSL_AD_UNEXPECTED_MESSAGE; 1318 SSLerror(s, ERR_R_INTERNAL_ERROR); 1319 goto f_err; 1320 case SSL3_RT_APPLICATION_DATA: 1321 /* At this point, we were expecting handshake data, 1322 * but have application data. If the library was 1323 * running inside ssl3_read() (i.e. in_read_app_data 1324 * is set) and it makes sense to read application data 1325 * at this point (session renegotiation not yet started), 1326 * we will indulge it. 1327 */ 1328 if (S3I(s)->in_read_app_data && 1329 (S3I(s)->total_renegotiations != 0) && 1330 (((S3I(s)->hs.state & SSL_ST_CONNECT) && 1331 (S3I(s)->hs.state >= SSL3_ST_CW_CLNT_HELLO_A) && 1332 (S3I(s)->hs.state <= SSL3_ST_CR_SRVR_HELLO_A)) || 1333 ((S3I(s)->hs.state & SSL_ST_ACCEPT) && 1334 (S3I(s)->hs.state <= SSL3_ST_SW_HELLO_REQ_A) && 1335 (S3I(s)->hs.state >= SSL3_ST_SR_CLNT_HELLO_A)))) { 1336 S3I(s)->in_read_app_data = 2; 1337 return (-1); 1338 } else { 1339 al = SSL_AD_UNEXPECTED_MESSAGE; 1340 SSLerror(s, SSL_R_UNEXPECTED_RECORD); 1341 goto f_err; 1342 } 1343 } 1344 /* not reached */ 1345 1346 f_err: 1347 ssl3_send_alert(s, SSL3_AL_FATAL, al); 1348 err: 1349 return (-1); 1350 } 1351 1352 int 1353 ssl3_do_change_cipher_spec(SSL *s) 1354 { 1355 int i; 1356 const char *sender; 1357 int slen; 1358 1359 if (S3I(s)->hs.state & SSL_ST_ACCEPT) 1360 i = SSL3_CHANGE_CIPHER_SERVER_READ; 1361 else 1362 i = SSL3_CHANGE_CIPHER_CLIENT_READ; 1363 1364 if (S3I(s)->hs.key_block == NULL) { 1365 if (s->session == NULL || s->session->master_key_length == 0) { 1366 /* might happen if dtls1_read_bytes() calls this */ 1367 SSLerror(s, SSL_R_CCS_RECEIVED_EARLY); 1368 return (0); 1369 } 1370 1371 s->session->cipher = S3I(s)->hs.new_cipher; 1372 if (!tls1_setup_key_block(s)) 1373 return (0); 1374 } 1375 1376 if (!tls1_change_cipher_state(s, i)) 1377 return (0); 1378 1379 /* we have to record the message digest at 1380 * this point so we can get it before we read 1381 * the finished message */ 1382 if (S3I(s)->hs.state & SSL_ST_CONNECT) { 1383 sender = TLS_MD_SERVER_FINISH_CONST; 1384 slen = TLS_MD_SERVER_FINISH_CONST_SIZE; 1385 } else { 1386 sender = TLS_MD_CLIENT_FINISH_CONST; 1387 slen = TLS_MD_CLIENT_FINISH_CONST_SIZE; 1388 } 1389 1390 i = tls1_final_finish_mac(s, sender, slen, 1391 S3I(s)->tmp.peer_finish_md); 1392 if (i == 0) { 1393 SSLerror(s, ERR_R_INTERNAL_ERROR); 1394 return 0; 1395 } 1396 S3I(s)->tmp.peer_finish_md_len = i; 1397 1398 return (1); 1399 } 1400 1401 int 1402 ssl3_send_alert(SSL *s, int level, int desc) 1403 { 1404 /* Map tls/ssl alert value to correct one */ 1405 desc = tls1_alert_code(desc); 1406 if (desc < 0) 1407 return -1; 1408 /* If a fatal one, remove from cache */ 1409 if ((level == 2) && (s->session != NULL)) 1410 SSL_CTX_remove_session(s->ctx, s->session); 1411 1412 S3I(s)->alert_dispatch = 1; 1413 S3I(s)->send_alert[0] = level; 1414 S3I(s)->send_alert[1] = desc; 1415 if (S3I(s)->wbuf.left == 0) /* data still being written out? */ 1416 return s->method->ssl_dispatch_alert(s); 1417 1418 /* else data is still being written out, we will get written 1419 * some time in the future */ 1420 return -1; 1421 } 1422 1423 int 1424 ssl3_dispatch_alert(SSL *s) 1425 { 1426 int i, j; 1427 void (*cb)(const SSL *ssl, int type, int val) = NULL; 1428 1429 S3I(s)->alert_dispatch = 0; 1430 i = do_ssl3_write(s, SSL3_RT_ALERT, &S3I(s)->send_alert[0], 2); 1431 if (i <= 0) { 1432 S3I(s)->alert_dispatch = 1; 1433 } else { 1434 /* Alert sent to BIO. If it is important, flush it now. 1435 * If the message does not get sent due to non-blocking IO, 1436 * we will not worry too much. */ 1437 if (S3I(s)->send_alert[0] == SSL3_AL_FATAL) 1438 (void)BIO_flush(s->wbio); 1439 1440 if (s->internal->msg_callback) 1441 s->internal->msg_callback(1, s->version, SSL3_RT_ALERT, 1442 S3I(s)->send_alert, 2, s, s->internal->msg_callback_arg); 1443 1444 if (s->internal->info_callback != NULL) 1445 cb = s->internal->info_callback; 1446 else if (s->ctx->internal->info_callback != NULL) 1447 cb = s->ctx->internal->info_callback; 1448 1449 if (cb != NULL) { 1450 j = (S3I(s)->send_alert[0]<<8)|S3I(s)->send_alert[1]; 1451 cb(s, SSL_CB_WRITE_ALERT, j); 1452 } 1453 } 1454 return (i); 1455 } 1456