s3_pkt.c revision 331638
1/* ssl/s3_pkt.c */ 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) 1998-2018 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 <stdio.h> 113#include <limits.h> 114#include <errno.h> 115#define USE_SOCKETS 116#include "ssl_locl.h" 117#include <openssl/evp.h> 118#include <openssl/buffer.h> 119#include <openssl/rand.h> 120 121#ifndef EVP_CIPH_FLAG_TLS1_1_MULTIBLOCK 122# define EVP_CIPH_FLAG_TLS1_1_MULTIBLOCK 0 123#endif 124 125#if defined(OPENSSL_SMALL_FOOTPRINT) || \ 126 !( defined(AES_ASM) && ( \ 127 defined(__x86_64) || defined(__x86_64__) || \ 128 defined(_M_AMD64) || defined(_M_X64) || \ 129 defined(__INTEL__) ) \ 130 ) 131# undef EVP_CIPH_FLAG_TLS1_1_MULTIBLOCK 132# define EVP_CIPH_FLAG_TLS1_1_MULTIBLOCK 0 133#endif 134 135static int do_ssl3_write(SSL *s, int type, const unsigned char *buf, 136 unsigned int len, int create_empty_fragment); 137static int ssl3_get_record(SSL *s); 138 139/* 140 * Return values are as per SSL_read() 141 */ 142int ssl3_read_n(SSL *s, int n, int max, int extend) 143{ 144 /* 145 * If extend == 0, obtain new n-byte packet; if extend == 1, increase 146 * packet by another n bytes. The packet will be in the sub-array of 147 * s->s3->rbuf.buf specified by s->packet and s->packet_length. (If 148 * s->read_ahead is set, 'max' bytes may be stored in rbuf [plus 149 * s->packet_length bytes if extend == 1].) 150 */ 151 int i, len, left; 152 long align = 0; 153 unsigned char *pkt; 154 SSL3_BUFFER *rb; 155 156 if (n <= 0) 157 return n; 158 159 rb = &(s->s3->rbuf); 160 if (rb->buf == NULL) 161 if (!ssl3_setup_read_buffer(s)) 162 return -1; 163 164 left = rb->left; 165#if defined(SSL3_ALIGN_PAYLOAD) && SSL3_ALIGN_PAYLOAD!=0 166 align = (long)rb->buf + SSL3_RT_HEADER_LENGTH; 167 align = (-align) & (SSL3_ALIGN_PAYLOAD - 1); 168#endif 169 170 if (!extend) { 171 /* start with empty packet ... */ 172 if (left == 0) 173 rb->offset = align; 174 else if (align != 0 && left >= SSL3_RT_HEADER_LENGTH) { 175 /* 176 * check if next packet length is large enough to justify payload 177 * alignment... 178 */ 179 pkt = rb->buf + rb->offset; 180 if (pkt[0] == SSL3_RT_APPLICATION_DATA 181 && (pkt[3] << 8 | pkt[4]) >= 128) { 182 /* 183 * Note that even if packet is corrupted and its length field 184 * is insane, we can only be led to wrong decision about 185 * whether memmove will occur or not. Header values has no 186 * effect on memmove arguments and therefore no buffer 187 * overrun can be triggered. 188 */ 189 memmove(rb->buf + align, pkt, left); 190 rb->offset = align; 191 } 192 } 193 s->packet = rb->buf + rb->offset; 194 s->packet_length = 0; 195 /* ... now we can act as if 'extend' was set */ 196 } 197 198 /* 199 * For DTLS/UDP reads should not span multiple packets because the read 200 * operation returns the whole packet at once (as long as it fits into 201 * the buffer). 202 */ 203 if (SSL_IS_DTLS(s)) { 204 if (left == 0 && extend) 205 return 0; 206 if (left > 0 && n > left) 207 n = left; 208 } 209 210 /* if there is enough in the buffer from a previous read, take some */ 211 if (left >= n) { 212 s->packet_length += n; 213 rb->left = left - n; 214 rb->offset += n; 215 return (n); 216 } 217 218 /* else we need to read more data */ 219 220 len = s->packet_length; 221 pkt = rb->buf + align; 222 /* 223 * Move any available bytes to front of buffer: 'len' bytes already 224 * pointed to by 'packet', 'left' extra ones at the end 225 */ 226 if (s->packet != pkt) { /* len > 0 */ 227 memmove(pkt, s->packet, len + left); 228 s->packet = pkt; 229 rb->offset = len + align; 230 } 231 232 if (n > (int)(rb->len - rb->offset)) { /* does not happen */ 233 SSLerr(SSL_F_SSL3_READ_N, ERR_R_INTERNAL_ERROR); 234 return -1; 235 } 236 237 /* We always act like read_ahead is set for DTLS */ 238 if (!s->read_ahead && !SSL_IS_DTLS(s)) 239 /* ignore max parameter */ 240 max = n; 241 else { 242 if (max < n) 243 max = n; 244 if (max > (int)(rb->len - rb->offset)) 245 max = rb->len - rb->offset; 246 } 247 248 while (left < n) { 249 /* 250 * Now we have len+left bytes at the front of s->s3->rbuf.buf and 251 * need to read in more until we have len+n (up to len+max if 252 * possible) 253 */ 254 255 clear_sys_error(); 256 if (s->rbio != NULL) { 257 s->rwstate = SSL_READING; 258 i = BIO_read(s->rbio, pkt + len + left, max - left); 259 } else { 260 SSLerr(SSL_F_SSL3_READ_N, SSL_R_READ_BIO_NOT_SET); 261 i = -1; 262 } 263 264 if (i <= 0) { 265 rb->left = left; 266 if (s->mode & SSL_MODE_RELEASE_BUFFERS && !SSL_IS_DTLS(s)) 267 if (len + left == 0) 268 ssl3_release_read_buffer(s); 269 return (i); 270 } 271 left += i; 272 /* 273 * reads should *never* span multiple packets for DTLS because the 274 * underlying transport protocol is message oriented as opposed to 275 * byte oriented as in the TLS case. 276 */ 277 if (SSL_IS_DTLS(s)) { 278 if (n > left) 279 n = left; /* makes the while condition false */ 280 } 281 } 282 283 /* done reading, now the book-keeping */ 284 rb->offset += n; 285 rb->left = left - n; 286 s->packet_length += n; 287 s->rwstate = SSL_NOTHING; 288 return (n); 289} 290 291/* 292 * MAX_EMPTY_RECORDS defines the number of consecutive, empty records that 293 * will be processed per call to ssl3_get_record. Without this limit an 294 * attacker could send empty records at a faster rate than we can process and 295 * cause ssl3_get_record to loop forever. 296 */ 297#define MAX_EMPTY_RECORDS 32 298 299/*- 300 * Call this to get a new input record. 301 * It will return <= 0 if more data is needed, normally due to an error 302 * or non-blocking IO. 303 * When it finishes, one packet has been decoded and can be found in 304 * ssl->s3->rrec.type - is the type of record 305 * ssl->s3->rrec.data, - data 306 * ssl->s3->rrec.length, - number of bytes 307 */ 308/* used only by ssl3_read_bytes */ 309static int ssl3_get_record(SSL *s) 310{ 311 int ssl_major, ssl_minor, al; 312 int enc_err, n, i, ret = -1; 313 SSL3_RECORD *rr; 314 SSL_SESSION *sess; 315 unsigned char *p; 316 unsigned char md[EVP_MAX_MD_SIZE]; 317 short version; 318 unsigned mac_size, orig_len; 319 size_t extra; 320 unsigned empty_record_count = 0; 321 322 rr = &(s->s3->rrec); 323 sess = s->session; 324 325 if (s->options & SSL_OP_MICROSOFT_BIG_SSLV3_BUFFER) 326 extra = SSL3_RT_MAX_EXTRA; 327 else 328 extra = 0; 329 if (extra && !s->s3->init_extra) { 330 /* 331 * An application error: SLS_OP_MICROSOFT_BIG_SSLV3_BUFFER set after 332 * ssl3_setup_buffers() was done 333 */ 334 SSLerr(SSL_F_SSL3_GET_RECORD, ERR_R_INTERNAL_ERROR); 335 return -1; 336 } 337 338 again: 339 /* check if we have the header */ 340 if ((s->rstate != SSL_ST_READ_BODY) || 341 (s->packet_length < SSL3_RT_HEADER_LENGTH)) { 342 n = ssl3_read_n(s, SSL3_RT_HEADER_LENGTH, s->s3->rbuf.len, 0); 343 if (n <= 0) 344 return (n); /* error or non-blocking */ 345 s->rstate = SSL_ST_READ_BODY; 346 347 p = s->packet; 348 if (s->msg_callback) 349 s->msg_callback(0, 0, SSL3_RT_HEADER, p, 5, s, 350 s->msg_callback_arg); 351 352 /* Pull apart the header into the SSL3_RECORD */ 353 rr->type = *(p++); 354 ssl_major = *(p++); 355 ssl_minor = *(p++); 356 version = (ssl_major << 8) | ssl_minor; 357 n2s(p, rr->length); 358#if 0 359 fprintf(stderr, "Record type=%d, Length=%d\n", rr->type, rr->length); 360#endif 361 362 /* Lets check version */ 363 if (!s->first_packet) { 364 if (version != s->version) { 365 SSLerr(SSL_F_SSL3_GET_RECORD, SSL_R_WRONG_VERSION_NUMBER); 366 if ((s->version & 0xFF00) == (version & 0xFF00) 367 && !s->enc_write_ctx && !s->write_hash) { 368 if (rr->type == SSL3_RT_ALERT) { 369 /* 370 * The record is using an incorrect version number, but 371 * what we've got appears to be an alert. We haven't 372 * read the body yet to check whether its a fatal or 373 * not - but chances are it is. We probably shouldn't 374 * send a fatal alert back. We'll just end. 375 */ 376 goto err; 377 } 378 /* 379 * Send back error using their minor version number :-) 380 */ 381 s->version = (unsigned short)version; 382 } 383 al = SSL_AD_PROTOCOL_VERSION; 384 goto f_err; 385 } 386 } 387 388 if ((version >> 8) != SSL3_VERSION_MAJOR) { 389 SSLerr(SSL_F_SSL3_GET_RECORD, SSL_R_WRONG_VERSION_NUMBER); 390 goto err; 391 } 392 393 if (rr->length > s->s3->rbuf.len - SSL3_RT_HEADER_LENGTH) { 394 al = SSL_AD_RECORD_OVERFLOW; 395 SSLerr(SSL_F_SSL3_GET_RECORD, SSL_R_PACKET_LENGTH_TOO_LONG); 396 goto f_err; 397 } 398 399 /* now s->rstate == SSL_ST_READ_BODY */ 400 } 401 402 /* s->rstate == SSL_ST_READ_BODY, get and decode the data */ 403 404 if (rr->length > s->packet_length - SSL3_RT_HEADER_LENGTH) { 405 /* now s->packet_length == SSL3_RT_HEADER_LENGTH */ 406 i = rr->length; 407 n = ssl3_read_n(s, i, i, 1); 408 if (n <= 0) 409 return (n); /* error or non-blocking io */ 410 /* 411 * now n == rr->length, and s->packet_length == SSL3_RT_HEADER_LENGTH 412 * + rr->length 413 */ 414 } 415 416 s->rstate = SSL_ST_READ_HEADER; /* set state for later operations */ 417 418 /* 419 * At this point, s->packet_length == SSL3_RT_HEADER_LNGTH + rr->length, 420 * and we have that many bytes in s->packet 421 */ 422 rr->input = &(s->packet[SSL3_RT_HEADER_LENGTH]); 423 424 /* 425 * ok, we can now read from 's->packet' data into 'rr' rr->input points 426 * at rr->length bytes, which need to be copied into rr->data by either 427 * the decryption or by the decompression When the data is 'copied' into 428 * the rr->data buffer, rr->input will be pointed at the new buffer 429 */ 430 431 /* 432 * We now have - encrypted [ MAC [ compressed [ plain ] ] ] rr->length 433 * bytes of encrypted compressed stuff. 434 */ 435 436 /* check is not needed I believe */ 437 if (rr->length > SSL3_RT_MAX_ENCRYPTED_LENGTH + extra) { 438 al = SSL_AD_RECORD_OVERFLOW; 439 SSLerr(SSL_F_SSL3_GET_RECORD, SSL_R_ENCRYPTED_LENGTH_TOO_LONG); 440 goto f_err; 441 } 442 443 /* decrypt in place in 'rr->input' */ 444 rr->data = rr->input; 445 446 enc_err = s->method->ssl3_enc->enc(s, 0); 447 /*- 448 * enc_err is: 449 * 0: (in non-constant time) if the record is publically invalid. 450 * 1: if the padding is valid 451 * -1: if the padding is invalid 452 */ 453 if (enc_err == 0) { 454 al = SSL_AD_DECRYPTION_FAILED; 455 SSLerr(SSL_F_SSL3_GET_RECORD, SSL_R_BLOCK_CIPHER_PAD_IS_WRONG); 456 goto f_err; 457 } 458#ifdef TLS_DEBUG 459 printf("dec %d\n", rr->length); 460 { 461 unsigned int z; 462 for (z = 0; z < rr->length; z++) 463 printf("%02X%c", rr->data[z], ((z + 1) % 16) ? ' ' : '\n'); 464 } 465 printf("\n"); 466#endif 467 468 /* r->length is now the compressed data plus mac */ 469 if ((sess != NULL) && 470 (s->enc_read_ctx != NULL) && (EVP_MD_CTX_md(s->read_hash) != NULL)) { 471 /* s->read_hash != NULL => mac_size != -1 */ 472 unsigned char *mac = NULL; 473 unsigned char mac_tmp[EVP_MAX_MD_SIZE]; 474 mac_size = EVP_MD_CTX_size(s->read_hash); 475 OPENSSL_assert(mac_size <= EVP_MAX_MD_SIZE); 476 477 /* 478 * kludge: *_cbc_remove_padding passes padding length in rr->type 479 */ 480 orig_len = rr->length + ((unsigned int)rr->type >> 8); 481 482 /* 483 * orig_len is the length of the record before any padding was 484 * removed. This is public information, as is the MAC in use, 485 * therefore we can safely process the record in a different amount 486 * of time if it's too short to possibly contain a MAC. 487 */ 488 if (orig_len < mac_size || 489 /* CBC records must have a padding length byte too. */ 490 (EVP_CIPHER_CTX_mode(s->enc_read_ctx) == EVP_CIPH_CBC_MODE && 491 orig_len < mac_size + 1)) { 492 al = SSL_AD_DECODE_ERROR; 493 SSLerr(SSL_F_SSL3_GET_RECORD, SSL_R_LENGTH_TOO_SHORT); 494 goto f_err; 495 } 496 497 if (EVP_CIPHER_CTX_mode(s->enc_read_ctx) == EVP_CIPH_CBC_MODE) { 498 /* 499 * We update the length so that the TLS header bytes can be 500 * constructed correctly but we need to extract the MAC in 501 * constant time from within the record, without leaking the 502 * contents of the padding bytes. 503 */ 504 mac = mac_tmp; 505 ssl3_cbc_copy_mac(mac_tmp, rr, mac_size, orig_len); 506 rr->length -= mac_size; 507 } else { 508 /* 509 * In this case there's no padding, so |orig_len| equals 510 * |rec->length| and we checked that there's enough bytes for 511 * |mac_size| above. 512 */ 513 rr->length -= mac_size; 514 mac = &rr->data[rr->length]; 515 } 516 517 i = s->method->ssl3_enc->mac(s, md, 0 /* not send */ ); 518 if (i < 0 || mac == NULL 519 || CRYPTO_memcmp(md, mac, (size_t)mac_size) != 0) 520 enc_err = -1; 521 if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH + extra + mac_size) 522 enc_err = -1; 523 } 524 525 if (enc_err < 0) { 526 /* 527 * A separate 'decryption_failed' alert was introduced with TLS 1.0, 528 * SSL 3.0 only has 'bad_record_mac'. But unless a decryption 529 * failure is directly visible from the ciphertext anyway, we should 530 * not reveal which kind of error occured -- this might become 531 * visible to an attacker (e.g. via a logfile) 532 */ 533 al = SSL_AD_BAD_RECORD_MAC; 534 SSLerr(SSL_F_SSL3_GET_RECORD, 535 SSL_R_DECRYPTION_FAILED_OR_BAD_RECORD_MAC); 536 goto f_err; 537 } 538 539 /* r->length is now just compressed */ 540 if (s->expand != NULL) { 541 if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH + extra) { 542 al = SSL_AD_RECORD_OVERFLOW; 543 SSLerr(SSL_F_SSL3_GET_RECORD, SSL_R_COMPRESSED_LENGTH_TOO_LONG); 544 goto f_err; 545 } 546 if (!ssl3_do_uncompress(s)) { 547 al = SSL_AD_DECOMPRESSION_FAILURE; 548 SSLerr(SSL_F_SSL3_GET_RECORD, SSL_R_BAD_DECOMPRESSION); 549 goto f_err; 550 } 551 } 552 553 if (rr->length > SSL3_RT_MAX_PLAIN_LENGTH + extra) { 554 al = SSL_AD_RECORD_OVERFLOW; 555 SSLerr(SSL_F_SSL3_GET_RECORD, SSL_R_DATA_LENGTH_TOO_LONG); 556 goto f_err; 557 } 558 559 rr->off = 0; 560 /*- 561 * So at this point the following is true 562 * ssl->s3->rrec.type is the type of record 563 * ssl->s3->rrec.length == number of bytes in record 564 * ssl->s3->rrec.off == offset to first valid byte 565 * ssl->s3->rrec.data == where to take bytes from, increment 566 * after use :-). 567 */ 568 569 /* we have pulled in a full packet so zero things */ 570 s->packet_length = 0; 571 572 /* just read a 0 length packet */ 573 if (rr->length == 0) { 574 empty_record_count++; 575 if (empty_record_count > MAX_EMPTY_RECORDS) { 576 al = SSL_AD_UNEXPECTED_MESSAGE; 577 SSLerr(SSL_F_SSL3_GET_RECORD, SSL_R_RECORD_TOO_SMALL); 578 goto f_err; 579 } 580 goto again; 581 } 582#if 0 583 fprintf(stderr, "Ultimate Record type=%d, Length=%d\n", rr->type, 584 rr->length); 585#endif 586 587 return (1); 588 589 f_err: 590 ssl3_send_alert(s, SSL3_AL_FATAL, al); 591 err: 592 return (ret); 593} 594 595int ssl3_do_uncompress(SSL *ssl) 596{ 597#ifndef OPENSSL_NO_COMP 598 int i; 599 SSL3_RECORD *rr; 600 601 rr = &(ssl->s3->rrec); 602 i = COMP_expand_block(ssl->expand, rr->comp, 603 SSL3_RT_MAX_PLAIN_LENGTH, rr->data, 604 (int)rr->length); 605 if (i < 0) 606 return (0); 607 else 608 rr->length = i; 609 rr->data = rr->comp; 610#endif 611 return (1); 612} 613 614int ssl3_do_compress(SSL *ssl) 615{ 616#ifndef OPENSSL_NO_COMP 617 int i; 618 SSL3_RECORD *wr; 619 620 wr = &(ssl->s3->wrec); 621 i = COMP_compress_block(ssl->compress, wr->data, 622 SSL3_RT_MAX_COMPRESSED_LENGTH, 623 wr->input, (int)wr->length); 624 if (i < 0) 625 return (0); 626 else 627 wr->length = i; 628 629 wr->input = wr->data; 630#endif 631 return (1); 632} 633 634/* 635 * Call this to write data in records of type 'type' It will return <= 0 if 636 * not all data has been sent or non-blocking IO. 637 */ 638int ssl3_write_bytes(SSL *s, int type, const void *buf_, int len) 639{ 640 const unsigned char *buf = buf_; 641 int tot; 642 unsigned int n, nw; 643#if !defined(OPENSSL_NO_MULTIBLOCK) && EVP_CIPH_FLAG_TLS1_1_MULTIBLOCK 644 unsigned int max_send_fragment; 645#endif 646 SSL3_BUFFER *wb = &(s->s3->wbuf); 647 int i; 648 649 s->rwstate = SSL_NOTHING; 650 OPENSSL_assert(s->s3->wnum <= INT_MAX); 651 tot = s->s3->wnum; 652 s->s3->wnum = 0; 653 654 if (SSL_in_init(s) && !s->in_handshake) { 655 i = s->handshake_func(s); 656 if (i < 0) 657 return (i); 658 if (i == 0) { 659 SSLerr(SSL_F_SSL3_WRITE_BYTES, SSL_R_SSL_HANDSHAKE_FAILURE); 660 return -1; 661 } 662 } 663 664 /* 665 * ensure that if we end up with a smaller value of data to write out 666 * than the the original len from a write which didn't complete for 667 * non-blocking I/O and also somehow ended up avoiding the check for 668 * this in ssl3_write_pending/SSL_R_BAD_WRITE_RETRY as it must never be 669 * possible to end up with (len-tot) as a large number that will then 670 * promptly send beyond the end of the users buffer ... so we trap and 671 * report the error in a way the user will notice 672 */ 673 if ((len < tot) || ((wb->left != 0) && (len < (tot + s->s3->wpend_tot)))) { 674 SSLerr(SSL_F_SSL3_WRITE_BYTES, SSL_R_BAD_LENGTH); 675 return (-1); 676 } 677 678 /* 679 * first check if there is a SSL3_BUFFER still being written out. This 680 * will happen with non blocking IO 681 */ 682 if (wb->left != 0) { 683 i = ssl3_write_pending(s, type, &buf[tot], s->s3->wpend_tot); 684 if (i <= 0) { 685 /* XXX should we ssl3_release_write_buffer if i<0? */ 686 s->s3->wnum = tot; 687 return i; 688 } 689 tot += i; /* this might be last fragment */ 690 } 691#if !defined(OPENSSL_NO_MULTIBLOCK) && EVP_CIPH_FLAG_TLS1_1_MULTIBLOCK 692 /* 693 * Depending on platform multi-block can deliver several *times* 694 * better performance. Downside is that it has to allocate 695 * jumbo buffer to accomodate up to 8 records, but the 696 * compromise is considered worthy. 697 */ 698 if (type == SSL3_RT_APPLICATION_DATA && 699 len >= 4 * (int)(max_send_fragment = s->max_send_fragment) && 700 s->compress == NULL && s->msg_callback == NULL && 701 SSL_USE_EXPLICIT_IV(s) && 702 s->enc_write_ctx != NULL && 703 EVP_CIPHER_flags(s->enc_write_ctx->cipher) & 704 EVP_CIPH_FLAG_TLS1_1_MULTIBLOCK) { 705 unsigned char aad[13]; 706 EVP_CTRL_TLS1_1_MULTIBLOCK_PARAM mb_param; 707 int packlen; 708 709 /* minimize address aliasing conflicts */ 710 if ((max_send_fragment & 0xfff) == 0) 711 max_send_fragment -= 512; 712 713 if (tot == 0 || wb->buf == NULL) { /* allocate jumbo buffer */ 714 ssl3_release_write_buffer(s); 715 716 packlen = EVP_CIPHER_CTX_ctrl(s->enc_write_ctx, 717 EVP_CTRL_TLS1_1_MULTIBLOCK_MAX_BUFSIZE, 718 max_send_fragment, NULL); 719 720 if (len >= 8 * (int)max_send_fragment) 721 packlen *= 8; 722 else 723 packlen *= 4; 724 725 wb->buf = OPENSSL_malloc(packlen); 726 if (!wb->buf) { 727 SSLerr(SSL_F_SSL3_WRITE_BYTES, ERR_R_MALLOC_FAILURE); 728 return -1; 729 } 730 wb->len = packlen; 731 } else if (tot == len) { /* done? */ 732 OPENSSL_free(wb->buf); /* free jumbo buffer */ 733 wb->buf = NULL; 734 return tot; 735 } 736 737 n = (len - tot); 738 for (;;) { 739 if (n < 4 * max_send_fragment) { 740 OPENSSL_free(wb->buf); /* free jumbo buffer */ 741 wb->buf = NULL; 742 break; 743 } 744 745 if (s->s3->alert_dispatch) { 746 i = s->method->ssl_dispatch_alert(s); 747 if (i <= 0) { 748 s->s3->wnum = tot; 749 return i; 750 } 751 } 752 753 if (n >= 8 * max_send_fragment) 754 nw = max_send_fragment * (mb_param.interleave = 8); 755 else 756 nw = max_send_fragment * (mb_param.interleave = 4); 757 758 memcpy(aad, s->s3->write_sequence, 8); 759 aad[8] = type; 760 aad[9] = (unsigned char)(s->version >> 8); 761 aad[10] = (unsigned char)(s->version); 762 aad[11] = 0; 763 aad[12] = 0; 764 mb_param.out = NULL; 765 mb_param.inp = aad; 766 mb_param.len = nw; 767 768 packlen = EVP_CIPHER_CTX_ctrl(s->enc_write_ctx, 769 EVP_CTRL_TLS1_1_MULTIBLOCK_AAD, 770 sizeof(mb_param), &mb_param); 771 772 if (packlen <= 0 || packlen > (int)wb->len) { /* never happens */ 773 OPENSSL_free(wb->buf); /* free jumbo buffer */ 774 wb->buf = NULL; 775 break; 776 } 777 778 mb_param.out = wb->buf; 779 mb_param.inp = &buf[tot]; 780 mb_param.len = nw; 781 782 if (EVP_CIPHER_CTX_ctrl(s->enc_write_ctx, 783 EVP_CTRL_TLS1_1_MULTIBLOCK_ENCRYPT, 784 sizeof(mb_param), &mb_param) <= 0) 785 return -1; 786 787 s->s3->write_sequence[7] += mb_param.interleave; 788 if (s->s3->write_sequence[7] < mb_param.interleave) { 789 int j = 6; 790 while (j >= 0 && (++s->s3->write_sequence[j--]) == 0) ; 791 } 792 793 wb->offset = 0; 794 wb->left = packlen; 795 796 s->s3->wpend_tot = nw; 797 s->s3->wpend_buf = &buf[tot]; 798 s->s3->wpend_type = type; 799 s->s3->wpend_ret = nw; 800 801 i = ssl3_write_pending(s, type, &buf[tot], nw); 802 if (i <= 0) { 803 if (i < 0 && (!s->wbio || !BIO_should_retry(s->wbio))) { 804 OPENSSL_free(wb->buf); 805 wb->buf = NULL; 806 } 807 s->s3->wnum = tot; 808 return i; 809 } 810 if (i == (int)n) { 811 OPENSSL_free(wb->buf); /* free jumbo buffer */ 812 wb->buf = NULL; 813 return tot + i; 814 } 815 n -= i; 816 tot += i; 817 } 818 } else 819#endif 820 if (tot == len) { /* done? */ 821 if (s->mode & SSL_MODE_RELEASE_BUFFERS && !SSL_IS_DTLS(s)) 822 ssl3_release_write_buffer(s); 823 824 return tot; 825 } 826 827 n = (len - tot); 828 for (;;) { 829 if (n > s->max_send_fragment) 830 nw = s->max_send_fragment; 831 else 832 nw = n; 833 834 i = do_ssl3_write(s, type, &(buf[tot]), nw, 0); 835 if (i <= 0) { 836 /* XXX should we ssl3_release_write_buffer if i<0? */ 837 s->s3->wnum = tot; 838 return i; 839 } 840 841 if ((i == (int)n) || 842 (type == SSL3_RT_APPLICATION_DATA && 843 (s->mode & SSL_MODE_ENABLE_PARTIAL_WRITE))) { 844 /* 845 * next chunk of data should get another prepended empty fragment 846 * in ciphersuites with known-IV weakness: 847 */ 848 s->s3->empty_fragment_done = 0; 849 850 if ((i == (int)n) && s->mode & SSL_MODE_RELEASE_BUFFERS && 851 !SSL_IS_DTLS(s)) 852 ssl3_release_write_buffer(s); 853 854 return tot + i; 855 } 856 857 n -= i; 858 tot += i; 859 } 860} 861 862static int do_ssl3_write(SSL *s, int type, const unsigned char *buf, 863 unsigned int len, int create_empty_fragment) 864{ 865 unsigned char *p, *plen; 866 int i, mac_size, clear = 0; 867 int prefix_len = 0; 868 int eivlen; 869 long align = 0; 870 SSL3_RECORD *wr; 871 SSL3_BUFFER *wb = &(s->s3->wbuf); 872 SSL_SESSION *sess; 873 874 /* 875 * first check if there is a SSL3_BUFFER still being written out. This 876 * will happen with non blocking IO 877 */ 878 if (wb->left != 0) 879 return (ssl3_write_pending(s, type, buf, len)); 880 881 /* If we have an alert to send, lets send it */ 882 if (s->s3->alert_dispatch) { 883 i = s->method->ssl_dispatch_alert(s); 884 if (i <= 0) 885 return (i); 886 /* if it went, fall through and send more stuff */ 887 } 888 889 if (wb->buf == NULL) 890 if (!ssl3_setup_write_buffer(s)) 891 return -1; 892 893 if (len == 0 && !create_empty_fragment) 894 return 0; 895 896 wr = &(s->s3->wrec); 897 sess = s->session; 898 899 if ((sess == NULL) || 900 (s->enc_write_ctx == NULL) || 901 (EVP_MD_CTX_md(s->write_hash) == NULL)) { 902#if 1 903 clear = s->enc_write_ctx ? 0 : 1; /* must be AEAD cipher */ 904#else 905 clear = 1; 906#endif 907 mac_size = 0; 908 } else { 909 mac_size = EVP_MD_CTX_size(s->write_hash); 910 if (mac_size < 0) 911 goto err; 912 } 913 914 /* 915 * 'create_empty_fragment' is true only when this function calls itself 916 */ 917 if (!clear && !create_empty_fragment && !s->s3->empty_fragment_done) { 918 /* 919 * countermeasure against known-IV weakness in CBC ciphersuites (see 920 * http://www.openssl.org/~bodo/tls-cbc.txt) 921 */ 922 923 if (s->s3->need_empty_fragments && type == SSL3_RT_APPLICATION_DATA) { 924 /* 925 * recursive function call with 'create_empty_fragment' set; this 926 * prepares and buffers the data for an empty fragment (these 927 * 'prefix_len' bytes are sent out later together with the actual 928 * payload) 929 */ 930 prefix_len = do_ssl3_write(s, type, buf, 0, 1); 931 if (prefix_len <= 0) 932 goto err; 933 934 if (prefix_len > 935 (SSL3_RT_HEADER_LENGTH + SSL3_RT_SEND_MAX_ENCRYPTED_OVERHEAD)) 936 { 937 /* insufficient space */ 938 SSLerr(SSL_F_DO_SSL3_WRITE, ERR_R_INTERNAL_ERROR); 939 goto err; 940 } 941 } 942 943 s->s3->empty_fragment_done = 1; 944 } 945 946 if (create_empty_fragment) { 947#if defined(SSL3_ALIGN_PAYLOAD) && SSL3_ALIGN_PAYLOAD!=0 948 /* 949 * extra fragment would be couple of cipher blocks, which would be 950 * multiple of SSL3_ALIGN_PAYLOAD, so if we want to align the real 951 * payload, then we can just pretent we simply have two headers. 952 */ 953 align = (long)wb->buf + 2 * SSL3_RT_HEADER_LENGTH; 954 align = (-align) & (SSL3_ALIGN_PAYLOAD - 1); 955#endif 956 p = wb->buf + align; 957 wb->offset = align; 958 } else if (prefix_len) { 959 p = wb->buf + wb->offset + prefix_len; 960 } else { 961#if defined(SSL3_ALIGN_PAYLOAD) && SSL3_ALIGN_PAYLOAD!=0 962 align = (long)wb->buf + SSL3_RT_HEADER_LENGTH; 963 align = (-align) & (SSL3_ALIGN_PAYLOAD - 1); 964#endif 965 p = wb->buf + align; 966 wb->offset = align; 967 } 968 969 /* write the header */ 970 971 *(p++) = type & 0xff; 972 wr->type = type; 973 974 *(p++) = (s->version >> 8); 975 /* 976 * Some servers hang if iniatial client hello is larger than 256 bytes 977 * and record version number > TLS 1.0 978 */ 979 if (s->state == SSL3_ST_CW_CLNT_HELLO_B 980 && !s->renegotiate && TLS1_get_version(s) > TLS1_VERSION) 981 *(p++) = 0x1; 982 else 983 *(p++) = s->version & 0xff; 984 985 /* field where we are to write out packet length */ 986 plen = p; 987 p += 2; 988 /* Explicit IV length, block ciphers appropriate version flag */ 989 if (s->enc_write_ctx && SSL_USE_EXPLICIT_IV(s)) { 990 int mode = EVP_CIPHER_CTX_mode(s->enc_write_ctx); 991 if (mode == EVP_CIPH_CBC_MODE) { 992 eivlen = EVP_CIPHER_CTX_iv_length(s->enc_write_ctx); 993 if (eivlen <= 1) 994 eivlen = 0; 995 } 996 /* Need explicit part of IV for GCM mode */ 997 else if (mode == EVP_CIPH_GCM_MODE) 998 eivlen = EVP_GCM_TLS_EXPLICIT_IV_LEN; 999 else 1000 eivlen = 0; 1001 } else 1002 eivlen = 0; 1003 1004 /* lets setup the record stuff. */ 1005 wr->data = p + eivlen; 1006 wr->length = (int)len; 1007 wr->input = (unsigned char *)buf; 1008 1009 /* 1010 * we now 'read' from wr->input, wr->length bytes into wr->data 1011 */ 1012 1013 /* first we compress */ 1014 if (s->compress != NULL) { 1015 if (!ssl3_do_compress(s)) { 1016 SSLerr(SSL_F_DO_SSL3_WRITE, SSL_R_COMPRESSION_FAILURE); 1017 goto err; 1018 } 1019 } else { 1020 memcpy(wr->data, wr->input, wr->length); 1021 wr->input = wr->data; 1022 } 1023 1024 /* 1025 * we should still have the output to wr->data and the input from 1026 * wr->input. Length should be wr->length. wr->data still points in the 1027 * wb->buf 1028 */ 1029 1030 if (mac_size != 0) { 1031 if (s->method->ssl3_enc->mac(s, &(p[wr->length + eivlen]), 1) < 0) 1032 goto err; 1033 wr->length += mac_size; 1034 } 1035 1036 wr->input = p; 1037 wr->data = p; 1038 1039 if (eivlen) { 1040 /* 1041 * if (RAND_pseudo_bytes(p, eivlen) <= 0) goto err; 1042 */ 1043 wr->length += eivlen; 1044 } 1045 1046 if (s->method->ssl3_enc->enc(s, 1) < 1) 1047 goto err; 1048 1049 /* record length after mac and block padding */ 1050 s2n(wr->length, plen); 1051 1052 if (s->msg_callback) 1053 s->msg_callback(1, 0, SSL3_RT_HEADER, plen - 5, 5, s, 1054 s->msg_callback_arg); 1055 1056 /* 1057 * we should now have wr->data pointing to the encrypted data, which is 1058 * wr->length long 1059 */ 1060 wr->type = type; /* not needed but helps for debugging */ 1061 wr->length += SSL3_RT_HEADER_LENGTH; 1062 1063 if (create_empty_fragment) { 1064 /* 1065 * we are in a recursive call; just return the length, don't write 1066 * out anything here 1067 */ 1068 return wr->length; 1069 } 1070 1071 /* now let's set up wb */ 1072 wb->left = prefix_len + wr->length; 1073 1074 /* 1075 * memorize arguments so that ssl3_write_pending can detect bad write 1076 * retries later 1077 */ 1078 s->s3->wpend_tot = len; 1079 s->s3->wpend_buf = buf; 1080 s->s3->wpend_type = type; 1081 s->s3->wpend_ret = len; 1082 1083 /* we now just need to write the buffer */ 1084 return ssl3_write_pending(s, type, buf, len); 1085 err: 1086 return -1; 1087} 1088 1089/* if s->s3->wbuf.left != 0, we need to call this 1090 * 1091 * Return values are as per SSL_write(), i.e. 1092 */ 1093int ssl3_write_pending(SSL *s, int type, const unsigned char *buf, 1094 unsigned int len) 1095{ 1096 int i; 1097 SSL3_BUFFER *wb = &(s->s3->wbuf); 1098 1099 if ((s->s3->wpend_tot > (int)len) 1100 || (!(s->mode & SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER) 1101 && (s->s3->wpend_buf != buf)) 1102 || (s->s3->wpend_type != type)) { 1103 SSLerr(SSL_F_SSL3_WRITE_PENDING, SSL_R_BAD_WRITE_RETRY); 1104 return (-1); 1105 } 1106 1107 for (;;) { 1108 clear_sys_error(); 1109 if (s->wbio != NULL) { 1110 s->rwstate = SSL_WRITING; 1111 i = BIO_write(s->wbio, 1112 (char *)&(wb->buf[wb->offset]), 1113 (unsigned int)wb->left); 1114 } else { 1115 SSLerr(SSL_F_SSL3_WRITE_PENDING, SSL_R_BIO_NOT_SET); 1116 i = -1; 1117 } 1118 if (i == wb->left) { 1119 wb->left = 0; 1120 wb->offset += i; 1121 s->rwstate = SSL_NOTHING; 1122 return (s->s3->wpend_ret); 1123 } else if (i <= 0) { 1124 if (SSL_IS_DTLS(s)) { 1125 /* 1126 * For DTLS, just drop it. That's kind of the whole point in 1127 * using a datagram service 1128 */ 1129 wb->left = 0; 1130 } 1131 return i; 1132 } 1133 wb->offset += i; 1134 wb->left -= i; 1135 } 1136} 1137 1138/*- 1139 * Return up to 'len' payload bytes received in 'type' records. 1140 * 'type' is one of the following: 1141 * 1142 * - SSL3_RT_HANDSHAKE (when ssl3_get_message calls us) 1143 * - SSL3_RT_APPLICATION_DATA (when ssl3_read calls us) 1144 * - 0 (during a shutdown, no data has to be returned) 1145 * 1146 * If we don't have stored data to work from, read a SSL/TLS record first 1147 * (possibly multiple records if we still don't have anything to return). 1148 * 1149 * This function must handle any surprises the peer may have for us, such as 1150 * Alert records (e.g. close_notify), ChangeCipherSpec records (not really 1151 * a surprise, but handled as if it were), or renegotiation requests. 1152 * Also if record payloads contain fragments too small to process, we store 1153 * them until there is enough for the respective protocol (the record protocol 1154 * may use arbitrary fragmentation and even interleaving): 1155 * Change cipher spec protocol 1156 * just 1 byte needed, no need for keeping anything stored 1157 * Alert protocol 1158 * 2 bytes needed (AlertLevel, AlertDescription) 1159 * Handshake protocol 1160 * 4 bytes needed (HandshakeType, uint24 length) -- we just have 1161 * to detect unexpected Client Hello and Hello Request messages 1162 * here, anything else is handled by higher layers 1163 * Application data protocol 1164 * none of our business 1165 */ 1166int ssl3_read_bytes(SSL *s, int type, unsigned char *buf, int len, int peek) 1167{ 1168 int al, i, j, ret; 1169 unsigned int n; 1170 SSL3_RECORD *rr; 1171 void (*cb) (const SSL *ssl, int type2, int val) = NULL; 1172 1173 if (s->s3->rbuf.buf == NULL) /* Not initialized yet */ 1174 if (!ssl3_setup_read_buffer(s)) 1175 return (-1); 1176 1177 if ((type && (type != SSL3_RT_APPLICATION_DATA) 1178 && (type != SSL3_RT_HANDSHAKE)) || (peek 1179 && (type != 1180 SSL3_RT_APPLICATION_DATA))) { 1181 SSLerr(SSL_F_SSL3_READ_BYTES, ERR_R_INTERNAL_ERROR); 1182 return -1; 1183 } 1184 1185 if ((type == SSL3_RT_HANDSHAKE) && (s->s3->handshake_fragment_len > 0)) 1186 /* (partially) satisfy request from storage */ 1187 { 1188 unsigned char *src = s->s3->handshake_fragment; 1189 unsigned char *dst = buf; 1190 unsigned int k; 1191 1192 /* peek == 0 */ 1193 n = 0; 1194 while ((len > 0) && (s->s3->handshake_fragment_len > 0)) { 1195 *dst++ = *src++; 1196 len--; 1197 s->s3->handshake_fragment_len--; 1198 n++; 1199 } 1200 /* move any remaining fragment bytes: */ 1201 for (k = 0; k < s->s3->handshake_fragment_len; k++) 1202 s->s3->handshake_fragment[k] = *src++; 1203 return n; 1204 } 1205 1206 /* 1207 * Now s->s3->handshake_fragment_len == 0 if type == SSL3_RT_HANDSHAKE. 1208 */ 1209 1210 if (!s->in_handshake && SSL_in_init(s)) { 1211 /* type == SSL3_RT_APPLICATION_DATA */ 1212 i = s->handshake_func(s); 1213 if (i < 0) 1214 return (i); 1215 if (i == 0) { 1216 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_R_SSL_HANDSHAKE_FAILURE); 1217 return (-1); 1218 } 1219 } 1220 start: 1221 s->rwstate = SSL_NOTHING; 1222 1223 /*- 1224 * s->s3->rrec.type - is the type of record 1225 * s->s3->rrec.data, - data 1226 * s->s3->rrec.off, - offset into 'data' for next read 1227 * s->s3->rrec.length, - number of bytes. 1228 */ 1229 rr = &(s->s3->rrec); 1230 1231 /* get new packet if necessary */ 1232 if ((rr->length == 0) || (s->rstate == SSL_ST_READ_BODY)) { 1233 ret = ssl3_get_record(s); 1234 if (ret <= 0) 1235 return (ret); 1236 } 1237 1238 /* 1239 * Reset the count of consecutive warning alerts if we've got a non-empty 1240 * record that isn't an alert. 1241 */ 1242 if (rr->type != SSL3_RT_ALERT && rr->length != 0) 1243 s->cert->alert_count = 0; 1244 1245 /* we now have a packet which can be read and processed */ 1246 1247 if (s->s3->change_cipher_spec /* set when we receive ChangeCipherSpec, 1248 * reset by ssl3_get_finished */ 1249 && (rr->type != SSL3_RT_HANDSHAKE)) { 1250 al = SSL_AD_UNEXPECTED_MESSAGE; 1251 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_R_DATA_BETWEEN_CCS_AND_FINISHED); 1252 goto f_err; 1253 } 1254 1255 /* 1256 * If the other end has shut down, throw anything we read away (even in 1257 * 'peek' mode) 1258 */ 1259 if (s->shutdown & SSL_RECEIVED_SHUTDOWN) { 1260 rr->length = 0; 1261 s->rwstate = SSL_NOTHING; 1262 return (0); 1263 } 1264 1265 if (type == rr->type) { /* SSL3_RT_APPLICATION_DATA or 1266 * SSL3_RT_HANDSHAKE */ 1267 /* 1268 * make sure that we are not getting application data when we are 1269 * doing a handshake for the first time 1270 */ 1271 if (SSL_in_init(s) && (type == SSL3_RT_APPLICATION_DATA) && 1272 (s->enc_read_ctx == NULL)) { 1273 al = SSL_AD_UNEXPECTED_MESSAGE; 1274 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_R_APP_DATA_IN_HANDSHAKE); 1275 goto f_err; 1276 } 1277 1278 if (len <= 0) 1279 return (len); 1280 1281 if ((unsigned int)len > rr->length) 1282 n = rr->length; 1283 else 1284 n = (unsigned int)len; 1285 1286 memcpy(buf, &(rr->data[rr->off]), n); 1287 if (!peek) { 1288 rr->length -= n; 1289 rr->off += n; 1290 if (rr->length == 0) { 1291 s->rstate = SSL_ST_READ_HEADER; 1292 rr->off = 0; 1293 if (s->mode & SSL_MODE_RELEASE_BUFFERS 1294 && s->s3->rbuf.left == 0) 1295 ssl3_release_read_buffer(s); 1296 } 1297 } 1298 return (n); 1299 } 1300 1301 /* 1302 * If we get here, then type != rr->type; if we have a handshake message, 1303 * then it was unexpected (Hello Request or Client Hello). 1304 */ 1305 1306 /* 1307 * In case of record types for which we have 'fragment' storage, fill 1308 * that so that we can process the data at a fixed place. 1309 */ 1310 { 1311 unsigned int dest_maxlen = 0; 1312 unsigned char *dest = NULL; 1313 unsigned int *dest_len = NULL; 1314 1315 if (rr->type == SSL3_RT_HANDSHAKE) { 1316 dest_maxlen = sizeof(s->s3->handshake_fragment); 1317 dest = s->s3->handshake_fragment; 1318 dest_len = &s->s3->handshake_fragment_len; 1319 } else if (rr->type == SSL3_RT_ALERT) { 1320 dest_maxlen = sizeof(s->s3->alert_fragment); 1321 dest = s->s3->alert_fragment; 1322 dest_len = &s->s3->alert_fragment_len; 1323 } 1324#ifndef OPENSSL_NO_HEARTBEATS 1325 else if (rr->type == TLS1_RT_HEARTBEAT) { 1326 i = tls1_process_heartbeat(s); 1327 1328 if (i < 0) 1329 return i; 1330 1331 rr->length = 0; 1332 if (s->mode & SSL_MODE_AUTO_RETRY) 1333 goto start; 1334 1335 /* Exit and notify application to read again */ 1336 s->rwstate = SSL_READING; 1337 BIO_clear_retry_flags(SSL_get_rbio(s)); 1338 BIO_set_retry_read(SSL_get_rbio(s)); 1339 return (-1); 1340 } 1341#endif 1342 1343 if (dest_maxlen > 0) { 1344 n = dest_maxlen - *dest_len; /* available space in 'dest' */ 1345 if (rr->length < n) 1346 n = rr->length; /* available bytes */ 1347 1348 /* now move 'n' bytes: */ 1349 while (n-- > 0) { 1350 dest[(*dest_len)++] = rr->data[rr->off++]; 1351 rr->length--; 1352 } 1353 1354 if (*dest_len < dest_maxlen) 1355 goto start; /* fragment was too small */ 1356 } 1357 } 1358 1359 /*- 1360 * s->s3->handshake_fragment_len == 4 iff rr->type == SSL3_RT_HANDSHAKE; 1361 * s->s3->alert_fragment_len == 2 iff rr->type == SSL3_RT_ALERT. 1362 * (Possibly rr is 'empty' now, i.e. rr->length may be 0.) 1363 */ 1364 1365 /* If we are a client, check for an incoming 'Hello Request': */ 1366 if ((!s->server) && 1367 (s->s3->handshake_fragment_len >= 4) && 1368 (s->s3->handshake_fragment[0] == SSL3_MT_HELLO_REQUEST) && 1369 (s->session != NULL) && (s->session->cipher != NULL)) { 1370 s->s3->handshake_fragment_len = 0; 1371 1372 if ((s->s3->handshake_fragment[1] != 0) || 1373 (s->s3->handshake_fragment[2] != 0) || 1374 (s->s3->handshake_fragment[3] != 0)) { 1375 al = SSL_AD_DECODE_ERROR; 1376 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_R_BAD_HELLO_REQUEST); 1377 goto f_err; 1378 } 1379 1380 if (s->msg_callback) 1381 s->msg_callback(0, s->version, SSL3_RT_HANDSHAKE, 1382 s->s3->handshake_fragment, 4, s, 1383 s->msg_callback_arg); 1384 1385 if (SSL_is_init_finished(s) && 1386 !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS) && 1387 !s->s3->renegotiate) { 1388 ssl3_renegotiate(s); 1389 if (ssl3_renegotiate_check(s)) { 1390 i = s->handshake_func(s); 1391 if (i < 0) 1392 return (i); 1393 if (i == 0) { 1394 SSLerr(SSL_F_SSL3_READ_BYTES, 1395 SSL_R_SSL_HANDSHAKE_FAILURE); 1396 return (-1); 1397 } 1398 1399 if (!(s->mode & SSL_MODE_AUTO_RETRY)) { 1400 if (s->s3->rbuf.left == 0) { /* no read-ahead left? */ 1401 BIO *bio; 1402 /* 1403 * In the case where we try to read application data, 1404 * but we trigger an SSL handshake, we return -1 with 1405 * the retry option set. Otherwise renegotiation may 1406 * cause nasty problems in the blocking world 1407 */ 1408 s->rwstate = SSL_READING; 1409 bio = SSL_get_rbio(s); 1410 BIO_clear_retry_flags(bio); 1411 BIO_set_retry_read(bio); 1412 return (-1); 1413 } 1414 } 1415 } 1416 } 1417 /* 1418 * we either finished a handshake or ignored the request, now try 1419 * again to obtain the (application) data we were asked for 1420 */ 1421 goto start; 1422 } 1423 1424 /* 1425 * If we are a server and get a client hello when renegotiation isn't 1426 * allowed send back a no renegotiation alert and carry on. 1427 */ 1428 if (s->server 1429 && SSL_is_init_finished(s) 1430 && !s->s3->send_connection_binding 1431 && s->version > SSL3_VERSION 1432 && s->s3->handshake_fragment_len >= SSL3_HM_HEADER_LENGTH 1433 && s->s3->handshake_fragment[0] == SSL3_MT_CLIENT_HELLO 1434 && s->s3->previous_client_finished_len != 0 1435 && (s->options & SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION) == 0) { 1436 s->s3->handshake_fragment_len = 0; 1437 rr->length = 0; 1438 ssl3_send_alert(s, SSL3_AL_WARNING, SSL_AD_NO_RENEGOTIATION); 1439 goto start; 1440 } 1441 1442 if (s->s3->alert_fragment_len >= 2) { 1443 int alert_level = s->s3->alert_fragment[0]; 1444 int alert_descr = s->s3->alert_fragment[1]; 1445 1446 s->s3->alert_fragment_len = 0; 1447 1448 if (s->msg_callback) 1449 s->msg_callback(0, s->version, SSL3_RT_ALERT, 1450 s->s3->alert_fragment, 2, s, s->msg_callback_arg); 1451 1452 if (s->info_callback != NULL) 1453 cb = s->info_callback; 1454 else if (s->ctx->info_callback != NULL) 1455 cb = s->ctx->info_callback; 1456 1457 if (cb != NULL) { 1458 j = (alert_level << 8) | alert_descr; 1459 cb(s, SSL_CB_READ_ALERT, j); 1460 } 1461 1462 if (alert_level == SSL3_AL_WARNING) { 1463 s->s3->warn_alert = alert_descr; 1464 1465 s->cert->alert_count++; 1466 if (s->cert->alert_count == MAX_WARN_ALERT_COUNT) { 1467 al = SSL_AD_UNEXPECTED_MESSAGE; 1468 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_R_TOO_MANY_WARN_ALERTS); 1469 goto f_err; 1470 } 1471 1472 if (alert_descr == SSL_AD_CLOSE_NOTIFY) { 1473 s->shutdown |= SSL_RECEIVED_SHUTDOWN; 1474 return (0); 1475 } 1476 /* 1477 * This is a warning but we receive it if we requested 1478 * renegotiation and the peer denied it. Terminate with a fatal 1479 * alert because if application tried to renegotiatie it 1480 * presumably had a good reason and expects it to succeed. In 1481 * future we might have a renegotiation where we don't care if 1482 * the peer refused it where we carry on. 1483 */ 1484 else if (alert_descr == SSL_AD_NO_RENEGOTIATION) { 1485 al = SSL_AD_HANDSHAKE_FAILURE; 1486 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_R_NO_RENEGOTIATION); 1487 goto f_err; 1488 } 1489#ifdef SSL_AD_MISSING_SRP_USERNAME 1490 else if (alert_descr == SSL_AD_MISSING_SRP_USERNAME) 1491 return (0); 1492#endif 1493 } else if (alert_level == SSL3_AL_FATAL) { 1494 char tmp[16]; 1495 1496 s->rwstate = SSL_NOTHING; 1497 s->s3->fatal_alert = alert_descr; 1498 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_AD_REASON_OFFSET + alert_descr); 1499 BIO_snprintf(tmp, sizeof(tmp), "%d", alert_descr); 1500 ERR_add_error_data(2, "SSL alert number ", tmp); 1501 s->shutdown |= SSL_RECEIVED_SHUTDOWN; 1502 SSL_CTX_remove_session(s->session_ctx, s->session); 1503 return (0); 1504 } else { 1505 al = SSL_AD_ILLEGAL_PARAMETER; 1506 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_R_UNKNOWN_ALERT_TYPE); 1507 goto f_err; 1508 } 1509 1510 goto start; 1511 } 1512 1513 if (s->shutdown & SSL_SENT_SHUTDOWN) { /* but we have not received a 1514 * shutdown */ 1515 s->rwstate = SSL_NOTHING; 1516 rr->length = 0; 1517 return (0); 1518 } 1519 1520 if (rr->type == SSL3_RT_CHANGE_CIPHER_SPEC) { 1521 /* 1522 * 'Change Cipher Spec' is just a single byte, so we know exactly 1523 * what the record payload has to look like 1524 */ 1525 if ((rr->length != 1) || (rr->off != 0) || 1526 (rr->data[0] != SSL3_MT_CCS)) { 1527 al = SSL_AD_ILLEGAL_PARAMETER; 1528 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_R_BAD_CHANGE_CIPHER_SPEC); 1529 goto f_err; 1530 } 1531 1532 /* Check we have a cipher to change to */ 1533 if (s->s3->tmp.new_cipher == NULL) { 1534 al = SSL_AD_UNEXPECTED_MESSAGE; 1535 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_R_CCS_RECEIVED_EARLY); 1536 goto f_err; 1537 } 1538 1539 if (!(s->s3->flags & SSL3_FLAGS_CCS_OK)) { 1540 al = SSL_AD_UNEXPECTED_MESSAGE; 1541 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_R_CCS_RECEIVED_EARLY); 1542 goto f_err; 1543 } 1544 1545 s->s3->flags &= ~SSL3_FLAGS_CCS_OK; 1546 1547 rr->length = 0; 1548 1549 if (s->msg_callback) 1550 s->msg_callback(0, s->version, SSL3_RT_CHANGE_CIPHER_SPEC, 1551 rr->data, 1, s, s->msg_callback_arg); 1552 1553 s->s3->change_cipher_spec = 1; 1554 if (!ssl3_do_change_cipher_spec(s)) 1555 goto err; 1556 else 1557 goto start; 1558 } 1559 1560 /* 1561 * Unexpected handshake message (Client Hello, or protocol violation) 1562 */ 1563 if ((s->s3->handshake_fragment_len >= 4) && !s->in_handshake) { 1564 if (((s->state & SSL_ST_MASK) == SSL_ST_OK) && 1565 !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS)) { 1566#if 0 /* worked only because C operator preferences 1567 * are not as expected (and because this is 1568 * not really needed for clients except for 1569 * detecting protocol violations): */ 1570 s->state = SSL_ST_BEFORE | (s->server) 1571 ? SSL_ST_ACCEPT : SSL_ST_CONNECT; 1572#else 1573 s->state = s->server ? SSL_ST_ACCEPT : SSL_ST_CONNECT; 1574#endif 1575 s->renegotiate = 1; 1576 s->new_session = 1; 1577 } 1578 i = s->handshake_func(s); 1579 if (i < 0) 1580 return (i); 1581 if (i == 0) { 1582 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_R_SSL_HANDSHAKE_FAILURE); 1583 return (-1); 1584 } 1585 1586 if (!(s->mode & SSL_MODE_AUTO_RETRY)) { 1587 if (s->s3->rbuf.left == 0) { /* no read-ahead left? */ 1588 BIO *bio; 1589 /* 1590 * In the case where we try to read application data, but we 1591 * trigger an SSL handshake, we return -1 with the retry 1592 * option set. Otherwise renegotiation may cause nasty 1593 * problems in the blocking world 1594 */ 1595 s->rwstate = SSL_READING; 1596 bio = SSL_get_rbio(s); 1597 BIO_clear_retry_flags(bio); 1598 BIO_set_retry_read(bio); 1599 return (-1); 1600 } 1601 } 1602 goto start; 1603 } 1604 1605 switch (rr->type) { 1606 default: 1607 /* 1608 * TLS 1.0 and 1.1 say you SHOULD ignore unrecognised record types, but 1609 * TLS 1.2 says you MUST send an unexpected message alert. We use the 1610 * TLS 1.2 behaviour for all protocol versions to prevent issues where 1611 * no progress is being made and the peer continually sends unrecognised 1612 * record types, using up resources processing them. 1613 */ 1614 al = SSL_AD_UNEXPECTED_MESSAGE; 1615 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_R_UNEXPECTED_RECORD); 1616 goto f_err; 1617 case SSL3_RT_CHANGE_CIPHER_SPEC: 1618 case SSL3_RT_ALERT: 1619 case SSL3_RT_HANDSHAKE: 1620 /* 1621 * we already handled all of these, with the possible exception of 1622 * SSL3_RT_HANDSHAKE when s->in_handshake is set, but that should not 1623 * happen when type != rr->type 1624 */ 1625 al = SSL_AD_UNEXPECTED_MESSAGE; 1626 SSLerr(SSL_F_SSL3_READ_BYTES, ERR_R_INTERNAL_ERROR); 1627 goto f_err; 1628 case SSL3_RT_APPLICATION_DATA: 1629 /* 1630 * At this point, we were expecting handshake data, but have 1631 * application data. If the library was running inside ssl3_read() 1632 * (i.e. in_read_app_data is set) and it makes sense to read 1633 * application data at this point (session renegotiation not yet 1634 * started), we will indulge it. 1635 */ 1636 if (s->s3->in_read_app_data && 1637 (s->s3->total_renegotiations != 0) && 1638 (((s->state & SSL_ST_CONNECT) && 1639 (s->state >= SSL3_ST_CW_CLNT_HELLO_A) && 1640 (s->state <= SSL3_ST_CR_SRVR_HELLO_A) 1641 ) || ((s->state & SSL_ST_ACCEPT) && 1642 (s->state <= SSL3_ST_SW_HELLO_REQ_A) && 1643 (s->state >= SSL3_ST_SR_CLNT_HELLO_A) 1644 ) 1645 )) { 1646 s->s3->in_read_app_data = 2; 1647 return (-1); 1648 } else { 1649 al = SSL_AD_UNEXPECTED_MESSAGE; 1650 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_R_UNEXPECTED_RECORD); 1651 goto f_err; 1652 } 1653 } 1654 /* not reached */ 1655 1656 f_err: 1657 ssl3_send_alert(s, SSL3_AL_FATAL, al); 1658 err: 1659 return (-1); 1660} 1661 1662int ssl3_do_change_cipher_spec(SSL *s) 1663{ 1664 int i; 1665 const char *sender; 1666 int slen; 1667 1668 if (s->state & SSL_ST_ACCEPT) 1669 i = SSL3_CHANGE_CIPHER_SERVER_READ; 1670 else 1671 i = SSL3_CHANGE_CIPHER_CLIENT_READ; 1672 1673 if (s->s3->tmp.key_block == NULL) { 1674 if (s->session == NULL || s->session->master_key_length == 0) { 1675 /* might happen if dtls1_read_bytes() calls this */ 1676 SSLerr(SSL_F_SSL3_DO_CHANGE_CIPHER_SPEC, 1677 SSL_R_CCS_RECEIVED_EARLY); 1678 return (0); 1679 } 1680 1681 s->session->cipher = s->s3->tmp.new_cipher; 1682 if (!s->method->ssl3_enc->setup_key_block(s)) 1683 return (0); 1684 } 1685 1686 if (!s->method->ssl3_enc->change_cipher_state(s, i)) 1687 return (0); 1688 1689 /* 1690 * we have to record the message digest at this point so we can get it 1691 * before we read the finished message 1692 */ 1693 if (s->state & SSL_ST_CONNECT) { 1694 sender = s->method->ssl3_enc->server_finished_label; 1695 slen = s->method->ssl3_enc->server_finished_label_len; 1696 } else { 1697 sender = s->method->ssl3_enc->client_finished_label; 1698 slen = s->method->ssl3_enc->client_finished_label_len; 1699 } 1700 1701 i = s->method->ssl3_enc->final_finish_mac(s, 1702 sender, slen, 1703 s->s3->tmp.peer_finish_md); 1704 if (i == 0) { 1705 SSLerr(SSL_F_SSL3_DO_CHANGE_CIPHER_SPEC, ERR_R_INTERNAL_ERROR); 1706 return 0; 1707 } 1708 s->s3->tmp.peer_finish_md_len = i; 1709 1710 return (1); 1711} 1712 1713int ssl3_send_alert(SSL *s, int level, int desc) 1714{ 1715 /* Map tls/ssl alert value to correct one */ 1716 desc = s->method->ssl3_enc->alert_value(desc); 1717 if (s->version == SSL3_VERSION && desc == SSL_AD_PROTOCOL_VERSION) 1718 desc = SSL_AD_HANDSHAKE_FAILURE; /* SSL 3.0 does not have 1719 * protocol_version alerts */ 1720 if (desc < 0) 1721 return -1; 1722 /* If a fatal one, remove from cache */ 1723 if ((level == 2) && (s->session != NULL)) 1724 SSL_CTX_remove_session(s->session_ctx, s->session); 1725 1726 s->s3->alert_dispatch = 1; 1727 s->s3->send_alert[0] = level; 1728 s->s3->send_alert[1] = desc; 1729 if (s->s3->wbuf.left == 0) /* data still being written out? */ 1730 return s->method->ssl_dispatch_alert(s); 1731 /* 1732 * else data is still being written out, we will get written some time in 1733 * the future 1734 */ 1735 return -1; 1736} 1737 1738int ssl3_dispatch_alert(SSL *s) 1739{ 1740 int i, j; 1741 void (*cb) (const SSL *ssl, int type, int val) = NULL; 1742 1743 s->s3->alert_dispatch = 0; 1744 i = do_ssl3_write(s, SSL3_RT_ALERT, &s->s3->send_alert[0], 2, 0); 1745 if (i <= 0) { 1746 s->s3->alert_dispatch = 1; 1747 } else { 1748 /* 1749 * Alert sent to BIO. If it is important, flush it now. If the 1750 * message does not get sent due to non-blocking IO, we will not 1751 * worry too much. 1752 */ 1753 if (s->s3->send_alert[0] == SSL3_AL_FATAL) 1754 (void)BIO_flush(s->wbio); 1755 1756 if (s->msg_callback) 1757 s->msg_callback(1, s->version, SSL3_RT_ALERT, s->s3->send_alert, 1758 2, s, s->msg_callback_arg); 1759 1760 if (s->info_callback != NULL) 1761 cb = s->info_callback; 1762 else if (s->ctx->info_callback != NULL) 1763 cb = s->ctx->info_callback; 1764 1765 if (cb != NULL) { 1766 j = (s->s3->send_alert[0] << 8) | s->s3->send_alert[1]; 1767 cb(s, SSL_CB_WRITE_ALERT, j); 1768 } 1769 } 1770 return (i); 1771} 1772