s3_pkt.c revision 280304
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) 1998-2002 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 <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 121static int do_ssl3_write(SSL *s, int type, const unsigned char *buf, 122 unsigned int len, int create_empty_fragment); 123static int ssl3_get_record(SSL *s); 124 125int ssl3_read_n(SSL *s, int n, int max, int extend) 126{ 127 /* 128 * If extend == 0, obtain new n-byte packet; if extend == 1, increase 129 * packet by another n bytes. The packet will be in the sub-array of 130 * s->s3->rbuf.buf specified by s->packet and s->packet_length. (If 131 * s->read_ahead is set, 'max' bytes may be stored in rbuf [plus 132 * s->packet_length bytes if extend == 1].) 133 */ 134 int i, len, left; 135 long align = 0; 136 unsigned char *pkt; 137 SSL3_BUFFER *rb; 138 139 if (n <= 0) 140 return n; 141 142 rb = &(s->s3->rbuf); 143 if (rb->buf == NULL) 144 if (!ssl3_setup_read_buffer(s)) 145 return -1; 146 147 left = rb->left; 148#if defined(SSL3_ALIGN_PAYLOAD) && SSL3_ALIGN_PAYLOAD!=0 149 align = (long)rb->buf + SSL3_RT_HEADER_LENGTH; 150 align = (-align) & (SSL3_ALIGN_PAYLOAD - 1); 151#endif 152 153 if (!extend) { 154 /* start with empty packet ... */ 155 if (left == 0) 156 rb->offset = align; 157 else if (align != 0 && left >= SSL3_RT_HEADER_LENGTH) { 158 /* 159 * check if next packet length is large enough to justify payload 160 * alignment... 161 */ 162 pkt = rb->buf + rb->offset; 163 if (pkt[0] == SSL3_RT_APPLICATION_DATA 164 && (pkt[3] << 8 | pkt[4]) >= 128) { 165 /* 166 * Note that even if packet is corrupted and its length field 167 * is insane, we can only be led to wrong decision about 168 * whether memmove will occur or not. Header values has no 169 * effect on memmove arguments and therefore no buffer 170 * overrun can be triggered. 171 */ 172 memmove(rb->buf + align, pkt, left); 173 rb->offset = align; 174 } 175 } 176 s->packet = rb->buf + rb->offset; 177 s->packet_length = 0; 178 /* ... now we can act as if 'extend' was set */ 179 } 180 181 /* 182 * For DTLS/UDP reads should not span multiple packets because the read 183 * operation returns the whole packet at once (as long as it fits into 184 * the buffer). 185 */ 186 if (SSL_version(s) == DTLS1_VERSION || SSL_version(s) == DTLS1_BAD_VER) { 187 if (left == 0 && extend) 188 return 0; 189 if (left > 0 && n > left) 190 n = left; 191 } 192 193 /* if there is enough in the buffer from a previous read, take some */ 194 if (left >= n) { 195 s->packet_length += n; 196 rb->left = left - n; 197 rb->offset += n; 198 return (n); 199 } 200 201 /* else we need to read more data */ 202 203 len = s->packet_length; 204 pkt = rb->buf + align; 205 /* 206 * Move any available bytes to front of buffer: 'len' bytes already 207 * pointed to by 'packet', 'left' extra ones at the end 208 */ 209 if (s->packet != pkt) { /* len > 0 */ 210 memmove(pkt, s->packet, len + left); 211 s->packet = pkt; 212 rb->offset = len + align; 213 } 214 215 if (n > (int)(rb->len - rb->offset)) { /* does not happen */ 216 SSLerr(SSL_F_SSL3_READ_N, ERR_R_INTERNAL_ERROR); 217 return -1; 218 } 219 220 /* We always act like read_ahead is set for DTLS */ 221 if (!s->read_ahead && !SSL_IS_DTLS(s)) 222 /* ignore max parameter */ 223 max = n; 224 else { 225 if (max < n) 226 max = n; 227 if (max > (int)(rb->len - rb->offset)) 228 max = rb->len - rb->offset; 229 } 230 231 while (left < n) { 232 /* 233 * Now we have len+left bytes at the front of s->s3->rbuf.buf and 234 * need to read in more until we have len+n (up to len+max if 235 * possible) 236 */ 237 238 clear_sys_error(); 239 if (s->rbio != NULL) { 240 s->rwstate = SSL_READING; 241 i = BIO_read(s->rbio, pkt + len + left, max - left); 242 } else { 243 SSLerr(SSL_F_SSL3_READ_N, SSL_R_READ_BIO_NOT_SET); 244 i = -1; 245 } 246 247 if (i <= 0) { 248 rb->left = left; 249 if (s->mode & SSL_MODE_RELEASE_BUFFERS && 250 SSL_version(s) != DTLS1_VERSION 251 && SSL_version(s) != DTLS1_BAD_VER) 252 if (len + left == 0) 253 ssl3_release_read_buffer(s); 254 return (i); 255 } 256 left += i; 257 /* 258 * reads should *never* span multiple packets for DTLS because the 259 * underlying transport protocol is message oriented as opposed to 260 * byte oriented as in the TLS case. 261 */ 262 if (SSL_version(s) == DTLS1_VERSION 263 || SSL_version(s) == DTLS1_BAD_VER) { 264 if (n > left) 265 n = left; /* makes the while condition false */ 266 } 267 } 268 269 /* done reading, now the book-keeping */ 270 rb->offset += n; 271 rb->left = left - n; 272 s->packet_length += n; 273 s->rwstate = SSL_NOTHING; 274 return (n); 275} 276 277/* 278 * MAX_EMPTY_RECORDS defines the number of consecutive, empty records that 279 * will be processed per call to ssl3_get_record. Without this limit an 280 * attacker could send empty records at a faster rate than we can process and 281 * cause ssl3_get_record to loop forever. 282 */ 283#define MAX_EMPTY_RECORDS 32 284 285/*- 286 * Call this to get a new input record. 287 * It will return <= 0 if more data is needed, normally due to an error 288 * or non-blocking IO. 289 * When it finishes, one packet has been decoded and can be found in 290 * ssl->s3->rrec.type - is the type of record 291 * ssl->s3->rrec.data, - data 292 * ssl->s3->rrec.length, - number of bytes 293 */ 294/* used only by ssl3_read_bytes */ 295static int ssl3_get_record(SSL *s) 296{ 297 int ssl_major, ssl_minor, al; 298 int enc_err, n, i, ret = -1; 299 SSL3_RECORD *rr; 300 SSL_SESSION *sess; 301 unsigned char *p; 302 unsigned char md[EVP_MAX_MD_SIZE]; 303 short version; 304 unsigned mac_size, orig_len; 305 size_t extra; 306 unsigned empty_record_count = 0; 307 308 rr = &(s->s3->rrec); 309 sess = s->session; 310 311 if (s->options & SSL_OP_MICROSOFT_BIG_SSLV3_BUFFER) 312 extra = SSL3_RT_MAX_EXTRA; 313 else 314 extra = 0; 315 if (extra && !s->s3->init_extra) { 316 /* 317 * An application error: SLS_OP_MICROSOFT_BIG_SSLV3_BUFFER set after 318 * ssl3_setup_buffers() was done 319 */ 320 SSLerr(SSL_F_SSL3_GET_RECORD, ERR_R_INTERNAL_ERROR); 321 return -1; 322 } 323 324 again: 325 /* check if we have the header */ 326 if ((s->rstate != SSL_ST_READ_BODY) || 327 (s->packet_length < SSL3_RT_HEADER_LENGTH)) { 328 n = ssl3_read_n(s, SSL3_RT_HEADER_LENGTH, s->s3->rbuf.len, 0); 329 if (n <= 0) 330 return (n); /* error or non-blocking */ 331 s->rstate = SSL_ST_READ_BODY; 332 333 p = s->packet; 334 335 /* Pull apart the header into the SSL3_RECORD */ 336 rr->type = *(p++); 337 ssl_major = *(p++); 338 ssl_minor = *(p++); 339 version = (ssl_major << 8) | ssl_minor; 340 n2s(p, rr->length); 341#if 0 342 fprintf(stderr, "Record type=%d, Length=%d\n", rr->type, rr->length); 343#endif 344 345 /* Lets check version */ 346 if (!s->first_packet) { 347 if (version != s->version) { 348 SSLerr(SSL_F_SSL3_GET_RECORD, SSL_R_WRONG_VERSION_NUMBER); 349 if ((s->version & 0xFF00) == (version & 0xFF00) 350 && !s->enc_write_ctx && !s->write_hash) 351 /* 352 * Send back error using their minor version number :-) 353 */ 354 s->version = (unsigned short)version; 355 al = SSL_AD_PROTOCOL_VERSION; 356 goto f_err; 357 } 358 } 359 360 if ((version >> 8) != SSL3_VERSION_MAJOR) { 361 SSLerr(SSL_F_SSL3_GET_RECORD, SSL_R_WRONG_VERSION_NUMBER); 362 goto err; 363 } 364 365 if (rr->length > s->s3->rbuf.len - SSL3_RT_HEADER_LENGTH) { 366 al = SSL_AD_RECORD_OVERFLOW; 367 SSLerr(SSL_F_SSL3_GET_RECORD, SSL_R_PACKET_LENGTH_TOO_LONG); 368 goto f_err; 369 } 370 371 /* now s->rstate == SSL_ST_READ_BODY */ 372 } 373 374 /* s->rstate == SSL_ST_READ_BODY, get and decode the data */ 375 376 if (rr->length > s->packet_length - SSL3_RT_HEADER_LENGTH) { 377 /* now s->packet_length == SSL3_RT_HEADER_LENGTH */ 378 i = rr->length; 379 n = ssl3_read_n(s, i, i, 1); 380 if (n <= 0) 381 return (n); /* error or non-blocking io */ 382 /* 383 * now n == rr->length, and s->packet_length == SSL3_RT_HEADER_LENGTH 384 * + rr->length 385 */ 386 } 387 388 s->rstate = SSL_ST_READ_HEADER; /* set state for later operations */ 389 390 /* 391 * At this point, s->packet_length == SSL3_RT_HEADER_LNGTH + rr->length, 392 * and we have that many bytes in s->packet 393 */ 394 rr->input = &(s->packet[SSL3_RT_HEADER_LENGTH]); 395 396 /* 397 * ok, we can now read from 's->packet' data into 'rr' rr->input points 398 * at rr->length bytes, which need to be copied into rr->data by either 399 * the decryption or by the decompression When the data is 'copied' into 400 * the rr->data buffer, rr->input will be pointed at the new buffer 401 */ 402 403 /* 404 * We now have - encrypted [ MAC [ compressed [ plain ] ] ] rr->length 405 * bytes of encrypted compressed stuff. 406 */ 407 408 /* check is not needed I believe */ 409 if (rr->length > SSL3_RT_MAX_ENCRYPTED_LENGTH + extra) { 410 al = SSL_AD_RECORD_OVERFLOW; 411 SSLerr(SSL_F_SSL3_GET_RECORD, SSL_R_ENCRYPTED_LENGTH_TOO_LONG); 412 goto f_err; 413 } 414 415 /* decrypt in place in 'rr->input' */ 416 rr->data = rr->input; 417 418 enc_err = s->method->ssl3_enc->enc(s, 0); 419 /*- 420 * enc_err is: 421 * 0: (in non-constant time) if the record is publically invalid. 422 * 1: if the padding is valid 423 * -1: if the padding is invalid 424 */ 425 if (enc_err == 0) { 426 al = SSL_AD_DECRYPTION_FAILED; 427 SSLerr(SSL_F_SSL3_GET_RECORD, SSL_R_BLOCK_CIPHER_PAD_IS_WRONG); 428 goto f_err; 429 } 430#ifdef TLS_DEBUG 431 printf("dec %d\n", rr->length); 432 { 433 unsigned int z; 434 for (z = 0; z < rr->length; z++) 435 printf("%02X%c", rr->data[z], ((z + 1) % 16) ? ' ' : '\n'); 436 } 437 printf("\n"); 438#endif 439 440 /* r->length is now the compressed data plus mac */ 441 if ((sess != NULL) && 442 (s->enc_read_ctx != NULL) && (EVP_MD_CTX_md(s->read_hash) != NULL)) { 443 /* s->read_hash != NULL => mac_size != -1 */ 444 unsigned char *mac = NULL; 445 unsigned char mac_tmp[EVP_MAX_MD_SIZE]; 446 mac_size = EVP_MD_CTX_size(s->read_hash); 447 OPENSSL_assert(mac_size <= EVP_MAX_MD_SIZE); 448 449 /* 450 * kludge: *_cbc_remove_padding passes padding length in rr->type 451 */ 452 orig_len = rr->length + ((unsigned int)rr->type >> 8); 453 454 /* 455 * orig_len is the length of the record before any padding was 456 * removed. This is public information, as is the MAC in use, 457 * therefore we can safely process the record in a different amount 458 * of time if it's too short to possibly contain a MAC. 459 */ 460 if (orig_len < mac_size || 461 /* CBC records must have a padding length byte too. */ 462 (EVP_CIPHER_CTX_mode(s->enc_read_ctx) == EVP_CIPH_CBC_MODE && 463 orig_len < mac_size + 1)) { 464 al = SSL_AD_DECODE_ERROR; 465 SSLerr(SSL_F_SSL3_GET_RECORD, SSL_R_LENGTH_TOO_SHORT); 466 goto f_err; 467 } 468 469 if (EVP_CIPHER_CTX_mode(s->enc_read_ctx) == EVP_CIPH_CBC_MODE) { 470 /* 471 * We update the length so that the TLS header bytes can be 472 * constructed correctly but we need to extract the MAC in 473 * constant time from within the record, without leaking the 474 * 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 /* 481 * In this case there's no padding, so |orig_len| equals 482 * |rec->length| and we checked that there's enough bytes for 483 * |mac_size| above. 484 */ 485 rr->length -= mac_size; 486 mac = &rr->data[rr->length]; 487 } 488 489 i = s->method->ssl3_enc->mac(s, md, 0 /* not send */ ); 490 if (i < 0 || mac == NULL 491 || CRYPTO_memcmp(md, mac, (size_t)mac_size) != 0) 492 enc_err = -1; 493 if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH + extra + mac_size) 494 enc_err = -1; 495 } 496 497 if (enc_err < 0) { 498 /* 499 * A separate 'decryption_failed' alert was introduced with TLS 1.0, 500 * SSL 3.0 only has 'bad_record_mac'. But unless a decryption 501 * failure is directly visible from the ciphertext anyway, we should 502 * not reveal which kind of error occured -- this might become 503 * visible to an attacker (e.g. via a logfile) 504 */ 505 al = SSL_AD_BAD_RECORD_MAC; 506 SSLerr(SSL_F_SSL3_GET_RECORD, 507 SSL_R_DECRYPTION_FAILED_OR_BAD_RECORD_MAC); 508 goto f_err; 509 } 510 511 /* r->length is now just compressed */ 512 if (s->expand != NULL) { 513 if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH + extra) { 514 al = SSL_AD_RECORD_OVERFLOW; 515 SSLerr(SSL_F_SSL3_GET_RECORD, SSL_R_COMPRESSED_LENGTH_TOO_LONG); 516 goto f_err; 517 } 518 if (!ssl3_do_uncompress(s)) { 519 al = SSL_AD_DECOMPRESSION_FAILURE; 520 SSLerr(SSL_F_SSL3_GET_RECORD, SSL_R_BAD_DECOMPRESSION); 521 goto f_err; 522 } 523 } 524 525 if (rr->length > SSL3_RT_MAX_PLAIN_LENGTH + extra) { 526 al = SSL_AD_RECORD_OVERFLOW; 527 SSLerr(SSL_F_SSL3_GET_RECORD, SSL_R_DATA_LENGTH_TOO_LONG); 528 goto f_err; 529 } 530 531 rr->off = 0; 532 /*- 533 * So at this point the following is true 534 * ssl->s3->rrec.type is the type of record 535 * ssl->s3->rrec.length == number of bytes in record 536 * ssl->s3->rrec.off == offset to first valid byte 537 * ssl->s3->rrec.data == where to take bytes from, increment 538 * after use :-). 539 */ 540 541 /* we have pulled in a full packet so zero things */ 542 s->packet_length = 0; 543 544 /* just read a 0 length packet */ 545 if (rr->length == 0) { 546 empty_record_count++; 547 if (empty_record_count > MAX_EMPTY_RECORDS) { 548 al = SSL_AD_UNEXPECTED_MESSAGE; 549 SSLerr(SSL_F_SSL3_GET_RECORD, SSL_R_RECORD_TOO_SMALL); 550 goto f_err; 551 } 552 goto again; 553 } 554#if 0 555 fprintf(stderr, "Ultimate Record type=%d, Length=%d\n", rr->type, 556 rr->length); 557#endif 558 559 return (1); 560 561 f_err: 562 ssl3_send_alert(s, SSL3_AL_FATAL, al); 563 err: 564 return (ret); 565} 566 567int ssl3_do_uncompress(SSL *ssl) 568{ 569#ifndef OPENSSL_NO_COMP 570 int i; 571 SSL3_RECORD *rr; 572 573 rr = &(ssl->s3->rrec); 574 i = COMP_expand_block(ssl->expand, rr->comp, 575 SSL3_RT_MAX_PLAIN_LENGTH, rr->data, 576 (int)rr->length); 577 if (i < 0) 578 return (0); 579 else 580 rr->length = i; 581 rr->data = rr->comp; 582#endif 583 return (1); 584} 585 586int ssl3_do_compress(SSL *ssl) 587{ 588#ifndef OPENSSL_NO_COMP 589 int i; 590 SSL3_RECORD *wr; 591 592 wr = &(ssl->s3->wrec); 593 i = COMP_compress_block(ssl->compress, wr->data, 594 SSL3_RT_MAX_COMPRESSED_LENGTH, 595 wr->input, (int)wr->length); 596 if (i < 0) 597 return (0); 598 else 599 wr->length = i; 600 601 wr->input = wr->data; 602#endif 603 return (1); 604} 605 606/* 607 * Call this to write data in records of type 'type' It will return <= 0 if 608 * not all data has been sent or non-blocking IO. 609 */ 610int ssl3_write_bytes(SSL *s, int type, const void *buf_, int len) 611{ 612 const unsigned char *buf = buf_; 613 unsigned int n, nw; 614 int i, tot; 615 616 s->rwstate = SSL_NOTHING; 617 OPENSSL_assert(s->s3->wnum <= INT_MAX); 618 tot = s->s3->wnum; 619 s->s3->wnum = 0; 620 621 if (SSL_in_init(s) && !s->in_handshake) { 622 i = s->handshake_func(s); 623 if (i < 0) 624 return (i); 625 if (i == 0) { 626 SSLerr(SSL_F_SSL3_WRITE_BYTES, SSL_R_SSL_HANDSHAKE_FAILURE); 627 return -1; 628 } 629 } 630 631 /* 632 * ensure that if we end up with a smaller value of data to write out 633 * than the the original len from a write which didn't complete for 634 * non-blocking I/O and also somehow ended up avoiding the check for 635 * this in ssl3_write_pending/SSL_R_BAD_WRITE_RETRY as it must never be 636 * possible to end up with (len-tot) as a large number that will then 637 * promptly send beyond the end of the users buffer ... so we trap and 638 * report the error in a way the user will notice 639 */ 640 if (len < tot) { 641 SSLerr(SSL_F_SSL3_WRITE_BYTES, SSL_R_BAD_LENGTH); 642 return (-1); 643 } 644 645 n = (len - tot); 646 for (;;) { 647 if (n > s->max_send_fragment) 648 nw = s->max_send_fragment; 649 else 650 nw = n; 651 652 i = do_ssl3_write(s, type, &(buf[tot]), nw, 0); 653 if (i <= 0) { 654 s->s3->wnum = tot; 655 return i; 656 } 657 658 if ((i == (int)n) || 659 (type == SSL3_RT_APPLICATION_DATA && 660 (s->mode & SSL_MODE_ENABLE_PARTIAL_WRITE))) { 661 /* 662 * next chunk of data should get another prepended empty fragment 663 * in ciphersuites with known-IV weakness: 664 */ 665 s->s3->empty_fragment_done = 0; 666 667 return tot + i; 668 } 669 670 n -= i; 671 tot += i; 672 } 673} 674 675static int do_ssl3_write(SSL *s, int type, const unsigned char *buf, 676 unsigned int len, int create_empty_fragment) 677{ 678 unsigned char *p, *plen; 679 int i, mac_size, clear = 0; 680 int prefix_len = 0; 681 int eivlen; 682 long align = 0; 683 SSL3_RECORD *wr; 684 SSL3_BUFFER *wb = &(s->s3->wbuf); 685 SSL_SESSION *sess; 686 687 /* 688 * first check if there is a SSL3_BUFFER still being written out. This 689 * will happen with non blocking IO 690 */ 691 if (wb->left != 0) 692 return (ssl3_write_pending(s, type, buf, len)); 693 694 /* If we have an alert to send, lets send it */ 695 if (s->s3->alert_dispatch) { 696 i = s->method->ssl_dispatch_alert(s); 697 if (i <= 0) 698 return (i); 699 /* if it went, fall through and send more stuff */ 700 } 701 702 if (wb->buf == NULL) 703 if (!ssl3_setup_write_buffer(s)) 704 return -1; 705 706 if (len == 0 && !create_empty_fragment) 707 return 0; 708 709 wr = &(s->s3->wrec); 710 sess = s->session; 711 712 if ((sess == NULL) || 713 (s->enc_write_ctx == NULL) || 714 (EVP_MD_CTX_md(s->write_hash) == NULL)) { 715#if 1 716 clear = s->enc_write_ctx ? 0 : 1; /* must be AEAD cipher */ 717#else 718 clear = 1; 719#endif 720 mac_size = 0; 721 } else { 722 mac_size = EVP_MD_CTX_size(s->write_hash); 723 if (mac_size < 0) 724 goto err; 725 } 726 727 /* 728 * 'create_empty_fragment' is true only when this function calls itself 729 */ 730 if (!clear && !create_empty_fragment && !s->s3->empty_fragment_done) { 731 /* 732 * countermeasure against known-IV weakness in CBC ciphersuites (see 733 * http://www.openssl.org/~bodo/tls-cbc.txt) 734 */ 735 736 if (s->s3->need_empty_fragments && type == SSL3_RT_APPLICATION_DATA) { 737 /* 738 * recursive function call with 'create_empty_fragment' set; this 739 * prepares and buffers the data for an empty fragment (these 740 * 'prefix_len' bytes are sent out later together with the actual 741 * payload) 742 */ 743 prefix_len = do_ssl3_write(s, type, buf, 0, 1); 744 if (prefix_len <= 0) 745 goto err; 746 747 if (prefix_len > 748 (SSL3_RT_HEADER_LENGTH + SSL3_RT_SEND_MAX_ENCRYPTED_OVERHEAD)) 749 { 750 /* insufficient space */ 751 SSLerr(SSL_F_DO_SSL3_WRITE, ERR_R_INTERNAL_ERROR); 752 goto err; 753 } 754 } 755 756 s->s3->empty_fragment_done = 1; 757 } 758 759 if (create_empty_fragment) { 760#if defined(SSL3_ALIGN_PAYLOAD) && SSL3_ALIGN_PAYLOAD!=0 761 /* 762 * extra fragment would be couple of cipher blocks, which would be 763 * multiple of SSL3_ALIGN_PAYLOAD, so if we want to align the real 764 * payload, then we can just pretent we simply have two headers. 765 */ 766 align = (long)wb->buf + 2 * SSL3_RT_HEADER_LENGTH; 767 align = (-align) & (SSL3_ALIGN_PAYLOAD - 1); 768#endif 769 p = wb->buf + align; 770 wb->offset = align; 771 } else if (prefix_len) { 772 p = wb->buf + wb->offset + prefix_len; 773 } else { 774#if defined(SSL3_ALIGN_PAYLOAD) && SSL3_ALIGN_PAYLOAD!=0 775 align = (long)wb->buf + SSL3_RT_HEADER_LENGTH; 776 align = (-align) & (SSL3_ALIGN_PAYLOAD - 1); 777#endif 778 p = wb->buf + align; 779 wb->offset = align; 780 } 781 782 /* write the header */ 783 784 *(p++) = type & 0xff; 785 wr->type = type; 786 787 *(p++) = (s->version >> 8); 788 /* 789 * Some servers hang if iniatial client hello is larger than 256 bytes 790 * and record version number > TLS 1.0 791 */ 792 if (s->state == SSL3_ST_CW_CLNT_HELLO_B 793 && !s->renegotiate && TLS1_get_version(s) > TLS1_VERSION) 794 *(p++) = 0x1; 795 else 796 *(p++) = s->version & 0xff; 797 798 /* field where we are to write out packet length */ 799 plen = p; 800 p += 2; 801 /* Explicit IV length, block ciphers and TLS version 1.1 or later */ 802 if (s->enc_write_ctx && s->version >= TLS1_1_VERSION) { 803 int mode = EVP_CIPHER_CTX_mode(s->enc_write_ctx); 804 if (mode == EVP_CIPH_CBC_MODE) { 805 eivlen = EVP_CIPHER_CTX_iv_length(s->enc_write_ctx); 806 if (eivlen <= 1) 807 eivlen = 0; 808 } 809 /* Need explicit part of IV for GCM mode */ 810 else if (mode == EVP_CIPH_GCM_MODE) 811 eivlen = EVP_GCM_TLS_EXPLICIT_IV_LEN; 812 else 813 eivlen = 0; 814 } else 815 eivlen = 0; 816 817 /* lets setup the record stuff. */ 818 wr->data = p + eivlen; 819 wr->length = (int)len; 820 wr->input = (unsigned char *)buf; 821 822 /* 823 * we now 'read' from wr->input, wr->length bytes into wr->data 824 */ 825 826 /* first we compress */ 827 if (s->compress != NULL) { 828 if (!ssl3_do_compress(s)) { 829 SSLerr(SSL_F_DO_SSL3_WRITE, SSL_R_COMPRESSION_FAILURE); 830 goto err; 831 } 832 } else { 833 memcpy(wr->data, wr->input, wr->length); 834 wr->input = wr->data; 835 } 836 837 /* 838 * we should still have the output to wr->data and the input from 839 * wr->input. Length should be wr->length. wr->data still points in the 840 * wb->buf 841 */ 842 843 if (mac_size != 0) { 844 if (s->method->ssl3_enc->mac(s, &(p[wr->length + eivlen]), 1) < 0) 845 goto err; 846 wr->length += mac_size; 847 } 848 849 wr->input = p; 850 wr->data = p; 851 852 if (eivlen) { 853 /* 854 * if (RAND_pseudo_bytes(p, eivlen) <= 0) goto err; 855 */ 856 wr->length += eivlen; 857 } 858 859 if (s->method->ssl3_enc->enc(s, 1) < 1) 860 goto err; 861 862 /* record length after mac and block padding */ 863 s2n(wr->length, plen); 864 865 /* 866 * we should now have wr->data pointing to the encrypted data, which is 867 * wr->length long 868 */ 869 wr->type = type; /* not needed but helps for debugging */ 870 wr->length += SSL3_RT_HEADER_LENGTH; 871 872 if (create_empty_fragment) { 873 /* 874 * we are in a recursive call; just return the length, don't write 875 * out anything here 876 */ 877 return wr->length; 878 } 879 880 /* now let's set up wb */ 881 wb->left = prefix_len + wr->length; 882 883 /* 884 * memorize arguments so that ssl3_write_pending can detect bad write 885 * retries later 886 */ 887 s->s3->wpend_tot = len; 888 s->s3->wpend_buf = buf; 889 s->s3->wpend_type = type; 890 s->s3->wpend_ret = len; 891 892 /* we now just need to write the buffer */ 893 return ssl3_write_pending(s, type, buf, len); 894 err: 895 return -1; 896} 897 898/* if s->s3->wbuf.left != 0, we need to call this */ 899int ssl3_write_pending(SSL *s, int type, const unsigned char *buf, 900 unsigned int len) 901{ 902 int i; 903 SSL3_BUFFER *wb = &(s->s3->wbuf); 904 905/* XXXX */ 906 if ((s->s3->wpend_tot > (int)len) 907 || ((s->s3->wpend_buf != buf) && 908 !(s->mode & SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER)) 909 || (s->s3->wpend_type != type)) { 910 SSLerr(SSL_F_SSL3_WRITE_PENDING, SSL_R_BAD_WRITE_RETRY); 911 return (-1); 912 } 913 914 for (;;) { 915 clear_sys_error(); 916 if (s->wbio != NULL) { 917 s->rwstate = SSL_WRITING; 918 i = BIO_write(s->wbio, 919 (char *)&(wb->buf[wb->offset]), 920 (unsigned int)wb->left); 921 } else { 922 SSLerr(SSL_F_SSL3_WRITE_PENDING, SSL_R_BIO_NOT_SET); 923 i = -1; 924 } 925 if (i == wb->left) { 926 wb->left = 0; 927 wb->offset += i; 928 if (s->mode & SSL_MODE_RELEASE_BUFFERS && 929 SSL_version(s) != DTLS1_VERSION 930 && SSL_version(s) != DTLS1_BAD_VER) 931 ssl3_release_write_buffer(s); 932 s->rwstate = SSL_NOTHING; 933 return (s->s3->wpend_ret); 934 } else if (i <= 0) { 935 if (s->version == DTLS1_VERSION || s->version == DTLS1_BAD_VER) { 936 /* 937 * For DTLS, just drop it. That's kind of the whole point in 938 * using a datagram service 939 */ 940 wb->left = 0; 941 } 942 return (i); 943 } 944 wb->offset += i; 945 wb->left -= i; 946 } 947} 948 949/*- 950 * Return up to 'len' payload bytes received in 'type' records. 951 * 'type' is one of the following: 952 * 953 * - SSL3_RT_HANDSHAKE (when ssl3_get_message calls us) 954 * - SSL3_RT_APPLICATION_DATA (when ssl3_read calls us) 955 * - 0 (during a shutdown, no data has to be returned) 956 * 957 * If we don't have stored data to work from, read a SSL/TLS record first 958 * (possibly multiple records if we still don't have anything to return). 959 * 960 * This function must handle any surprises the peer may have for us, such as 961 * Alert records (e.g. close_notify), ChangeCipherSpec records (not really 962 * a surprise, but handled as if it were), or renegotiation requests. 963 * Also if record payloads contain fragments too small to process, we store 964 * them until there is enough for the respective protocol (the record protocol 965 * may use arbitrary fragmentation and even interleaving): 966 * Change cipher spec protocol 967 * just 1 byte needed, no need for keeping anything stored 968 * Alert protocol 969 * 2 bytes needed (AlertLevel, AlertDescription) 970 * Handshake protocol 971 * 4 bytes needed (HandshakeType, uint24 length) -- we just have 972 * to detect unexpected Client Hello and Hello Request messages 973 * here, anything else is handled by higher layers 974 * Application data protocol 975 * none of our business 976 */ 977int ssl3_read_bytes(SSL *s, int type, unsigned char *buf, int len, int peek) 978{ 979 int al, i, j, ret; 980 unsigned int n; 981 SSL3_RECORD *rr; 982 void (*cb) (const SSL *ssl, int type2, int val) = NULL; 983 984 if (s->s3->rbuf.buf == NULL) /* Not initialized yet */ 985 if (!ssl3_setup_read_buffer(s)) 986 return (-1); 987 988 if ((type && (type != SSL3_RT_APPLICATION_DATA) 989 && (type != SSL3_RT_HANDSHAKE)) || (peek 990 && (type != 991 SSL3_RT_APPLICATION_DATA))) { 992 SSLerr(SSL_F_SSL3_READ_BYTES, ERR_R_INTERNAL_ERROR); 993 return -1; 994 } 995 996 if ((type == SSL3_RT_HANDSHAKE) && (s->s3->handshake_fragment_len > 0)) 997 /* (partially) satisfy request from storage */ 998 { 999 unsigned char *src = s->s3->handshake_fragment; 1000 unsigned char *dst = buf; 1001 unsigned int k; 1002 1003 /* peek == 0 */ 1004 n = 0; 1005 while ((len > 0) && (s->s3->handshake_fragment_len > 0)) { 1006 *dst++ = *src++; 1007 len--; 1008 s->s3->handshake_fragment_len--; 1009 n++; 1010 } 1011 /* move any remaining fragment bytes: */ 1012 for (k = 0; k < s->s3->handshake_fragment_len; k++) 1013 s->s3->handshake_fragment[k] = *src++; 1014 return n; 1015 } 1016 1017 /* 1018 * Now s->s3->handshake_fragment_len == 0 if type == SSL3_RT_HANDSHAKE. 1019 */ 1020 1021 if (!s->in_handshake && SSL_in_init(s)) { 1022 /* type == SSL3_RT_APPLICATION_DATA */ 1023 i = s->handshake_func(s); 1024 if (i < 0) 1025 return (i); 1026 if (i == 0) { 1027 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_R_SSL_HANDSHAKE_FAILURE); 1028 return (-1); 1029 } 1030 } 1031 start: 1032 s->rwstate = SSL_NOTHING; 1033 1034 /*- 1035 * s->s3->rrec.type - is the type of record 1036 * s->s3->rrec.data, - data 1037 * s->s3->rrec.off, - offset into 'data' for next read 1038 * s->s3->rrec.length, - number of bytes. 1039 */ 1040 rr = &(s->s3->rrec); 1041 1042 /* get new packet if necessary */ 1043 if ((rr->length == 0) || (s->rstate == SSL_ST_READ_BODY)) { 1044 ret = ssl3_get_record(s); 1045 if (ret <= 0) 1046 return (ret); 1047 } 1048 1049 /* we now have a packet which can be read and processed */ 1050 1051 if (s->s3->change_cipher_spec /* set when we receive ChangeCipherSpec, 1052 * reset by ssl3_get_finished */ 1053 && (rr->type != SSL3_RT_HANDSHAKE)) { 1054 al = SSL_AD_UNEXPECTED_MESSAGE; 1055 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_R_DATA_BETWEEN_CCS_AND_FINISHED); 1056 goto f_err; 1057 } 1058 1059 /* 1060 * If the other end has shut down, throw anything we read away (even in 1061 * 'peek' mode) 1062 */ 1063 if (s->shutdown & SSL_RECEIVED_SHUTDOWN) { 1064 rr->length = 0; 1065 s->rwstate = SSL_NOTHING; 1066 return (0); 1067 } 1068 1069 if (type == rr->type) { /* SSL3_RT_APPLICATION_DATA or 1070 * SSL3_RT_HANDSHAKE */ 1071 /* 1072 * make sure that we are not getting application data when we are 1073 * doing a handshake for the first time 1074 */ 1075 if (SSL_in_init(s) && (type == SSL3_RT_APPLICATION_DATA) && 1076 (s->enc_read_ctx == NULL)) { 1077 al = SSL_AD_UNEXPECTED_MESSAGE; 1078 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_R_APP_DATA_IN_HANDSHAKE); 1079 goto f_err; 1080 } 1081 1082 if (len <= 0) 1083 return (len); 1084 1085 if ((unsigned int)len > rr->length) 1086 n = rr->length; 1087 else 1088 n = (unsigned int)len; 1089 1090 memcpy(buf, &(rr->data[rr->off]), n); 1091 if (!peek) { 1092 rr->length -= n; 1093 rr->off += n; 1094 if (rr->length == 0) { 1095 s->rstate = SSL_ST_READ_HEADER; 1096 rr->off = 0; 1097 if (s->mode & SSL_MODE_RELEASE_BUFFERS 1098 && s->s3->rbuf.left == 0) 1099 ssl3_release_read_buffer(s); 1100 } 1101 } 1102 return (n); 1103 } 1104 1105 /* 1106 * If we get here, then type != rr->type; if we have a handshake message, 1107 * then it was unexpected (Hello Request or Client Hello). 1108 */ 1109 1110 /* 1111 * In case of record types for which we have 'fragment' storage, fill 1112 * that so that we can process the data at a fixed place. 1113 */ 1114 { 1115 unsigned int dest_maxlen = 0; 1116 unsigned char *dest = NULL; 1117 unsigned int *dest_len = NULL; 1118 1119 if (rr->type == SSL3_RT_HANDSHAKE) { 1120 dest_maxlen = sizeof s->s3->handshake_fragment; 1121 dest = s->s3->handshake_fragment; 1122 dest_len = &s->s3->handshake_fragment_len; 1123 } else if (rr->type == SSL3_RT_ALERT) { 1124 dest_maxlen = sizeof s->s3->alert_fragment; 1125 dest = s->s3->alert_fragment; 1126 dest_len = &s->s3->alert_fragment_len; 1127 } 1128#ifndef OPENSSL_NO_HEARTBEATS 1129 else if (rr->type == TLS1_RT_HEARTBEAT) { 1130 tls1_process_heartbeat(s); 1131 1132 /* Exit and notify application to read again */ 1133 rr->length = 0; 1134 s->rwstate = SSL_READING; 1135 BIO_clear_retry_flags(SSL_get_rbio(s)); 1136 BIO_set_retry_read(SSL_get_rbio(s)); 1137 return (-1); 1138 } 1139#endif 1140 1141 if (dest_maxlen > 0) { 1142 n = dest_maxlen - *dest_len; /* available space in 'dest' */ 1143 if (rr->length < n) 1144 n = rr->length; /* available bytes */ 1145 1146 /* now move 'n' bytes: */ 1147 while (n-- > 0) { 1148 dest[(*dest_len)++] = rr->data[rr->off++]; 1149 rr->length--; 1150 } 1151 1152 if (*dest_len < dest_maxlen) 1153 goto start; /* fragment was too small */ 1154 } 1155 } 1156 1157 /*- 1158 * s->s3->handshake_fragment_len == 4 iff rr->type == SSL3_RT_HANDSHAKE; 1159 * s->s3->alert_fragment_len == 2 iff rr->type == SSL3_RT_ALERT. 1160 * (Possibly rr is 'empty' now, i.e. rr->length may be 0.) 1161 */ 1162 1163 /* If we are a client, check for an incoming 'Hello Request': */ 1164 if ((!s->server) && 1165 (s->s3->handshake_fragment_len >= 4) && 1166 (s->s3->handshake_fragment[0] == SSL3_MT_HELLO_REQUEST) && 1167 (s->session != NULL) && (s->session->cipher != NULL)) { 1168 s->s3->handshake_fragment_len = 0; 1169 1170 if ((s->s3->handshake_fragment[1] != 0) || 1171 (s->s3->handshake_fragment[2] != 0) || 1172 (s->s3->handshake_fragment[3] != 0)) { 1173 al = SSL_AD_DECODE_ERROR; 1174 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_R_BAD_HELLO_REQUEST); 1175 goto f_err; 1176 } 1177 1178 if (s->msg_callback) 1179 s->msg_callback(0, s->version, SSL3_RT_HANDSHAKE, 1180 s->s3->handshake_fragment, 4, s, 1181 s->msg_callback_arg); 1182 1183 if (SSL_is_init_finished(s) && 1184 !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS) && 1185 !s->s3->renegotiate) { 1186 ssl3_renegotiate(s); 1187 if (ssl3_renegotiate_check(s)) { 1188 i = s->handshake_func(s); 1189 if (i < 0) 1190 return (i); 1191 if (i == 0) { 1192 SSLerr(SSL_F_SSL3_READ_BYTES, 1193 SSL_R_SSL_HANDSHAKE_FAILURE); 1194 return (-1); 1195 } 1196 1197 if (!(s->mode & SSL_MODE_AUTO_RETRY)) { 1198 if (s->s3->rbuf.left == 0) { /* no read-ahead left? */ 1199 BIO *bio; 1200 /* 1201 * In the case where we try to read application data, 1202 * but we trigger an SSL handshake, we return -1 with 1203 * the retry option set. Otherwise renegotiation may 1204 * cause nasty problems in the blocking world 1205 */ 1206 s->rwstate = SSL_READING; 1207 bio = SSL_get_rbio(s); 1208 BIO_clear_retry_flags(bio); 1209 BIO_set_retry_read(bio); 1210 return (-1); 1211 } 1212 } 1213 } 1214 } 1215 /* 1216 * we either finished a handshake or ignored the request, now try 1217 * again to obtain the (application) data we were asked for 1218 */ 1219 goto start; 1220 } 1221 /* 1222 * If we are a server and get a client hello when renegotiation isn't 1223 * allowed send back a no renegotiation alert and carry on. WARNING: 1224 * experimental code, needs reviewing (steve) 1225 */ 1226 if (s->server && 1227 SSL_is_init_finished(s) && 1228 !s->s3->send_connection_binding && 1229 (s->version > SSL3_VERSION) && 1230 (s->s3->handshake_fragment_len >= 4) && 1231 (s->s3->handshake_fragment[0] == SSL3_MT_CLIENT_HELLO) && 1232 (s->session != NULL) && (s->session->cipher != NULL) && 1233 !(s->ctx->options & SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION)) { 1234 /* 1235 * s->s3->handshake_fragment_len = 0; 1236 */ 1237 rr->length = 0; 1238 ssl3_send_alert(s, SSL3_AL_WARNING, SSL_AD_NO_RENEGOTIATION); 1239 goto start; 1240 } 1241 if (s->s3->alert_fragment_len >= 2) { 1242 int alert_level = s->s3->alert_fragment[0]; 1243 int alert_descr = s->s3->alert_fragment[1]; 1244 1245 s->s3->alert_fragment_len = 0; 1246 1247 if (s->msg_callback) 1248 s->msg_callback(0, s->version, SSL3_RT_ALERT, 1249 s->s3->alert_fragment, 2, s, s->msg_callback_arg); 1250 1251 if (s->info_callback != NULL) 1252 cb = s->info_callback; 1253 else if (s->ctx->info_callback != NULL) 1254 cb = s->ctx->info_callback; 1255 1256 if (cb != NULL) { 1257 j = (alert_level << 8) | alert_descr; 1258 cb(s, SSL_CB_READ_ALERT, j); 1259 } 1260 1261 if (alert_level == SSL3_AL_WARNING) { 1262 s->s3->warn_alert = alert_descr; 1263 if (alert_descr == SSL_AD_CLOSE_NOTIFY) { 1264 s->shutdown |= SSL_RECEIVED_SHUTDOWN; 1265 return (0); 1266 } 1267 /* 1268 * This is a warning but we receive it if we requested 1269 * renegotiation and the peer denied it. Terminate with a fatal 1270 * alert because if application tried to renegotiatie it 1271 * presumably had a good reason and expects it to succeed. In 1272 * future we might have a renegotiation where we don't care if 1273 * the peer refused it where we carry on. 1274 */ 1275 else if (alert_descr == SSL_AD_NO_RENEGOTIATION) { 1276 al = SSL_AD_HANDSHAKE_FAILURE; 1277 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_R_NO_RENEGOTIATION); 1278 goto f_err; 1279 } 1280#ifdef SSL_AD_MISSING_SRP_USERNAME 1281 else if (alert_descr == SSL_AD_MISSING_SRP_USERNAME) 1282 return (0); 1283#endif 1284 } else if (alert_level == SSL3_AL_FATAL) { 1285 char tmp[16]; 1286 1287 s->rwstate = SSL_NOTHING; 1288 s->s3->fatal_alert = alert_descr; 1289 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_AD_REASON_OFFSET + alert_descr); 1290 BIO_snprintf(tmp, sizeof tmp, "%d", alert_descr); 1291 ERR_add_error_data(2, "SSL alert number ", tmp); 1292 s->shutdown |= SSL_RECEIVED_SHUTDOWN; 1293 SSL_CTX_remove_session(s->ctx, s->session); 1294 return (0); 1295 } else { 1296 al = SSL_AD_ILLEGAL_PARAMETER; 1297 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_R_UNKNOWN_ALERT_TYPE); 1298 goto f_err; 1299 } 1300 1301 goto start; 1302 } 1303 1304 if (s->shutdown & SSL_SENT_SHUTDOWN) { /* but we have not received a 1305 * shutdown */ 1306 s->rwstate = SSL_NOTHING; 1307 rr->length = 0; 1308 return (0); 1309 } 1310 1311 if (rr->type == SSL3_RT_CHANGE_CIPHER_SPEC) { 1312 /* 1313 * 'Change Cipher Spec' is just a single byte, so we know exactly 1314 * what the record payload has to look like 1315 */ 1316 if ((rr->length != 1) || (rr->off != 0) || 1317 (rr->data[0] != SSL3_MT_CCS)) { 1318 al = SSL_AD_ILLEGAL_PARAMETER; 1319 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_R_BAD_CHANGE_CIPHER_SPEC); 1320 goto f_err; 1321 } 1322 1323 /* Check we have a cipher to change to */ 1324 if (s->s3->tmp.new_cipher == NULL) { 1325 al = SSL_AD_UNEXPECTED_MESSAGE; 1326 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_R_CCS_RECEIVED_EARLY); 1327 goto f_err; 1328 } 1329 1330 if (!(s->s3->flags & SSL3_FLAGS_CCS_OK)) { 1331 al = SSL_AD_UNEXPECTED_MESSAGE; 1332 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_R_CCS_RECEIVED_EARLY); 1333 goto f_err; 1334 } 1335 1336 s->s3->flags &= ~SSL3_FLAGS_CCS_OK; 1337 1338 rr->length = 0; 1339 1340 if (s->msg_callback) 1341 s->msg_callback(0, s->version, SSL3_RT_CHANGE_CIPHER_SPEC, 1342 rr->data, 1, s, s->msg_callback_arg); 1343 1344 s->s3->change_cipher_spec = 1; 1345 if (!ssl3_do_change_cipher_spec(s)) 1346 goto err; 1347 else 1348 goto start; 1349 } 1350 1351 /* 1352 * Unexpected handshake message (Client Hello, or protocol violation) 1353 */ 1354 if ((s->s3->handshake_fragment_len >= 4) && !s->in_handshake) { 1355 if (((s->state & SSL_ST_MASK) == SSL_ST_OK) && 1356 !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS)) { 1357#if 0 /* worked only because C operator preferences 1358 * are not as expected (and because this is 1359 * not really needed for clients except for 1360 * detecting protocol violations): */ 1361 s->state = SSL_ST_BEFORE | (s->server) 1362 ? SSL_ST_ACCEPT : SSL_ST_CONNECT; 1363#else 1364 s->state = s->server ? SSL_ST_ACCEPT : SSL_ST_CONNECT; 1365#endif 1366 s->renegotiate = 1; 1367 s->new_session = 1; 1368 } 1369 i = s->handshake_func(s); 1370 if (i < 0) 1371 return (i); 1372 if (i == 0) { 1373 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_R_SSL_HANDSHAKE_FAILURE); 1374 return (-1); 1375 } 1376 1377 if (!(s->mode & SSL_MODE_AUTO_RETRY)) { 1378 if (s->s3->rbuf.left == 0) { /* no read-ahead left? */ 1379 BIO *bio; 1380 /* 1381 * In the case where we try to read application data, but we 1382 * trigger an SSL handshake, we return -1 with the retry 1383 * option set. Otherwise renegotiation may cause nasty 1384 * problems in the blocking world 1385 */ 1386 s->rwstate = SSL_READING; 1387 bio = SSL_get_rbio(s); 1388 BIO_clear_retry_flags(bio); 1389 BIO_set_retry_read(bio); 1390 return (-1); 1391 } 1392 } 1393 goto start; 1394 } 1395 1396 switch (rr->type) { 1397 default: 1398#ifndef OPENSSL_NO_TLS 1399 /* 1400 * TLS up to v1.1 just ignores unknown message types: TLS v1.2 give 1401 * an unexpected message alert. 1402 */ 1403 if (s->version >= TLS1_VERSION && s->version <= TLS1_1_VERSION) { 1404 rr->length = 0; 1405 goto start; 1406 } 1407#endif 1408 al = SSL_AD_UNEXPECTED_MESSAGE; 1409 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_R_UNEXPECTED_RECORD); 1410 goto f_err; 1411 case SSL3_RT_CHANGE_CIPHER_SPEC: 1412 case SSL3_RT_ALERT: 1413 case SSL3_RT_HANDSHAKE: 1414 /* 1415 * we already handled all of these, with the possible exception of 1416 * SSL3_RT_HANDSHAKE when s->in_handshake is set, but that should not 1417 * happen when type != rr->type 1418 */ 1419 al = SSL_AD_UNEXPECTED_MESSAGE; 1420 SSLerr(SSL_F_SSL3_READ_BYTES, ERR_R_INTERNAL_ERROR); 1421 goto f_err; 1422 case SSL3_RT_APPLICATION_DATA: 1423 /* 1424 * At this point, we were expecting handshake data, but have 1425 * application data. If the library was running inside ssl3_read() 1426 * (i.e. in_read_app_data is set) and it makes sense to read 1427 * application data at this point (session renegotiation not yet 1428 * started), we will indulge it. 1429 */ 1430 if (s->s3->in_read_app_data && 1431 (s->s3->total_renegotiations != 0) && 1432 (((s->state & SSL_ST_CONNECT) && 1433 (s->state >= SSL3_ST_CW_CLNT_HELLO_A) && 1434 (s->state <= SSL3_ST_CR_SRVR_HELLO_A) 1435 ) || ((s->state & SSL_ST_ACCEPT) && 1436 (s->state <= SSL3_ST_SW_HELLO_REQ_A) && 1437 (s->state >= SSL3_ST_SR_CLNT_HELLO_A) 1438 ) 1439 )) { 1440 s->s3->in_read_app_data = 2; 1441 return (-1); 1442 } else { 1443 al = SSL_AD_UNEXPECTED_MESSAGE; 1444 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_R_UNEXPECTED_RECORD); 1445 goto f_err; 1446 } 1447 } 1448 /* not reached */ 1449 1450 f_err: 1451 ssl3_send_alert(s, SSL3_AL_FATAL, al); 1452 err: 1453 return (-1); 1454} 1455 1456int ssl3_do_change_cipher_spec(SSL *s) 1457{ 1458 int i; 1459 const char *sender; 1460 int slen; 1461 1462 if (s->state & SSL_ST_ACCEPT) 1463 i = SSL3_CHANGE_CIPHER_SERVER_READ; 1464 else 1465 i = SSL3_CHANGE_CIPHER_CLIENT_READ; 1466 1467 if (s->s3->tmp.key_block == NULL) { 1468 if (s->session == NULL || s->session->master_key_length == 0) { 1469 /* might happen if dtls1_read_bytes() calls this */ 1470 SSLerr(SSL_F_SSL3_DO_CHANGE_CIPHER_SPEC, 1471 SSL_R_CCS_RECEIVED_EARLY); 1472 return (0); 1473 } 1474 1475 s->session->cipher = s->s3->tmp.new_cipher; 1476 if (!s->method->ssl3_enc->setup_key_block(s)) 1477 return (0); 1478 } 1479 1480 if (!s->method->ssl3_enc->change_cipher_state(s, i)) 1481 return (0); 1482 1483 /* 1484 * we have to record the message digest at this point so we can get it 1485 * before we read the finished message 1486 */ 1487 if (s->state & SSL_ST_CONNECT) { 1488 sender = s->method->ssl3_enc->server_finished_label; 1489 slen = s->method->ssl3_enc->server_finished_label_len; 1490 } else { 1491 sender = s->method->ssl3_enc->client_finished_label; 1492 slen = s->method->ssl3_enc->client_finished_label_len; 1493 } 1494 1495 i = s->method->ssl3_enc->final_finish_mac(s, 1496 sender, slen, 1497 s->s3->tmp.peer_finish_md); 1498 if (i == 0) { 1499 SSLerr(SSL_F_SSL3_DO_CHANGE_CIPHER_SPEC, ERR_R_INTERNAL_ERROR); 1500 return 0; 1501 } 1502 s->s3->tmp.peer_finish_md_len = i; 1503 1504 return (1); 1505} 1506 1507int ssl3_send_alert(SSL *s, int level, int desc) 1508{ 1509 /* Map tls/ssl alert value to correct one */ 1510 desc = s->method->ssl3_enc->alert_value(desc); 1511 if (s->version == SSL3_VERSION && desc == SSL_AD_PROTOCOL_VERSION) 1512 desc = SSL_AD_HANDSHAKE_FAILURE; /* SSL 3.0 does not have 1513 * protocol_version alerts */ 1514 if (desc < 0) 1515 return -1; 1516 /* If a fatal one, remove from cache */ 1517 if ((level == 2) && (s->session != NULL)) 1518 SSL_CTX_remove_session(s->ctx, s->session); 1519 1520 s->s3->alert_dispatch = 1; 1521 s->s3->send_alert[0] = level; 1522 s->s3->send_alert[1] = desc; 1523 if (s->s3->wbuf.left == 0) /* data still being written out? */ 1524 return s->method->ssl_dispatch_alert(s); 1525 /* 1526 * else data is still being written out, we will get written some time in 1527 * the future 1528 */ 1529 return -1; 1530} 1531 1532int ssl3_dispatch_alert(SSL *s) 1533{ 1534 int i, j; 1535 void (*cb) (const SSL *ssl, int type, int val) = NULL; 1536 1537 s->s3->alert_dispatch = 0; 1538 i = do_ssl3_write(s, SSL3_RT_ALERT, &s->s3->send_alert[0], 2, 0); 1539 if (i <= 0) { 1540 s->s3->alert_dispatch = 1; 1541 } else { 1542 /* 1543 * Alert sent to BIO. If it is important, flush it now. If the 1544 * message does not get sent due to non-blocking IO, we will not 1545 * worry too much. 1546 */ 1547 if (s->s3->send_alert[0] == SSL3_AL_FATAL) 1548 (void)BIO_flush(s->wbio); 1549 1550 if (s->msg_callback) 1551 s->msg_callback(1, s->version, SSL3_RT_ALERT, s->s3->send_alert, 1552 2, s, s->msg_callback_arg); 1553 1554 if (s->info_callback != NULL) 1555 cb = s->info_callback; 1556 else if (s->ctx->info_callback != NULL) 1557 cb = s->ctx->info_callback; 1558 1559 if (cb != NULL) { 1560 j = (s->s3->send_alert[0] << 8) | s->s3->send_alert[1]; 1561 cb(s, SSL_CB_WRITE_ALERT, j); 1562 } 1563 } 1564 return (i); 1565} 1566