s3_pkt.c revision 277195
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 /* If extend == 0, obtain new n-byte packet; if extend == 1, increase 128 * packet by another n bytes. 129 * The packet will be in the sub-array of s->s3->rbuf.buf specified 130 * by s->packet and s->packet_length. 131 * (If s->read_ahead is set, 'max' bytes may be stored in rbuf 132 * [plus 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) return n; 140 141 rb = &(s->s3->rbuf); 142 if (rb->buf == NULL) 143 if (!ssl3_setup_read_buffer(s)) 144 return -1; 145 146 left = rb->left; 147#if defined(SSL3_ALIGN_PAYLOAD) && SSL3_ALIGN_PAYLOAD!=0 148 align = (long)rb->buf + SSL3_RT_HEADER_LENGTH; 149 align = (-align)&(SSL3_ALIGN_PAYLOAD-1); 150#endif 151 152 if (!extend) 153 { 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 160 * enough to justify payload alignment... */ 161 pkt = rb->buf + rb->offset; 162 if (pkt[0] == SSL3_RT_APPLICATION_DATA 163 && (pkt[3]<<8|pkt[4]) >= 128) 164 { 165 /* Note that even if packet is corrupted 166 * and its length field is insane, we can 167 * only be led to wrong decision about 168 * whether memmove will occur or not. 169 * Header values has no effect on memmove 170 * arguments and therefore no buffer 171 * overrun can be triggered. */ 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 /* For DTLS/UDP reads should not span multiple packets 182 * because the read operation returns the whole packet 183 * at once (as long as it fits into the buffer). */ 184 if (SSL_version(s) == DTLS1_VERSION || SSL_version(s) == DTLS1_BAD_VER) 185 { 186 if (left == 0 && extend) 187 return 0; 188 if (left > 0 && n > left) 189 n = left; 190 } 191 192 /* if there is enough in the buffer from a previous read, take some */ 193 if (left >= n) 194 { 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 /* Move any available bytes to front of buffer: 206 * 'len' bytes already pointed to by 'packet', 207 * 'left' extra ones at the end */ 208 if (s->packet != pkt) /* len > 0 */ 209 { 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 { 217 SSLerr(SSL_F_SSL3_READ_N,ERR_R_INTERNAL_ERROR); 218 return -1; 219 } 220 221 if (!s->read_ahead) 222 /* ignore max parameter */ 223 max = n; 224 else 225 { 226 if (max < n) 227 max = n; 228 if (max > (int)(rb->len - rb->offset)) 229 max = rb->len - rb->offset; 230 } 231 232 while (left < n) 233 { 234 /* Now we have len+left bytes at the front of s->s3->rbuf.buf 235 * and need to read in more until we have len+n (up to 236 * len+max if possible) */ 237 238 clear_sys_error(); 239 if (s->rbio != NULL) 240 { 241 s->rwstate=SSL_READING; 242 i=BIO_read(s->rbio,pkt+len+left, max-left); 243 } 244 else 245 { 246 SSLerr(SSL_F_SSL3_READ_N,SSL_R_READ_BIO_NOT_SET); 247 i = -1; 248 } 249 250 if (i <= 0) 251 { 252 rb->left = left; 253 if (s->mode & SSL_MODE_RELEASE_BUFFERS && 254 SSL_version(s) != DTLS1_VERSION && SSL_version(s) != DTLS1_BAD_VER) 255 if (len+left == 0) 256 ssl3_release_read_buffer(s); 257 return(i); 258 } 259 left+=i; 260 /* reads should *never* span multiple packets for DTLS because 261 * the underlying transport protocol is message oriented as opposed 262 * to byte oriented as in the TLS case. */ 263 if (SSL_version(s) == DTLS1_VERSION || SSL_version(s) == DTLS1_BAD_VER) 264 { 265 if (n > left) 266 n = left; /* makes the while condition false */ 267 } 268 } 269 270 /* done reading, now the book-keeping */ 271 rb->offset += n; 272 rb->left = left - n; 273 s->packet_length += n; 274 s->rwstate=SSL_NOTHING; 275 return(n); 276 } 277 278/* MAX_EMPTY_RECORDS defines the number of consecutive, empty records that will 279 * be processed per call to ssl3_get_record. Without this limit an attacker 280 * could send empty records at a faster rate than we can process and cause 281 * ssl3_get_record to loop forever. */ 282#define MAX_EMPTY_RECORDS 32 283 284/* Call this to get a new input record. 285 * It will return <= 0 if more data is needed, normally due to an error 286 * or non-blocking IO. 287 * When it finishes, one packet has been decoded and can be found in 288 * ssl->s3->rrec.type - is the type of record 289 * ssl->s3->rrec.data, - data 290 * ssl->s3->rrec.length, - number of bytes 291 */ 292/* used only by ssl3_read_bytes */ 293static int ssl3_get_record(SSL *s) 294 { 295 int ssl_major,ssl_minor,al; 296 int enc_err,n,i,ret= -1; 297 SSL3_RECORD *rr; 298 SSL_SESSION *sess; 299 unsigned char *p; 300 unsigned char md[EVP_MAX_MD_SIZE]; 301 short version; 302 unsigned mac_size, orig_len; 303 size_t extra; 304 unsigned empty_record_count = 0; 305 306 rr= &(s->s3->rrec); 307 sess=s->session; 308 309 if (s->options & SSL_OP_MICROSOFT_BIG_SSLV3_BUFFER) 310 extra=SSL3_RT_MAX_EXTRA; 311 else 312 extra=0; 313 if (extra && !s->s3->init_extra) 314 { 315 /* An application error: SLS_OP_MICROSOFT_BIG_SSLV3_BUFFER 316 * set after ssl3_setup_buffers() was done */ 317 SSLerr(SSL_F_SSL3_GET_RECORD, ERR_R_INTERNAL_ERROR); 318 return -1; 319 } 320 321again: 322 /* check if we have the header */ 323 if ( (s->rstate != SSL_ST_READ_BODY) || 324 (s->packet_length < SSL3_RT_HEADER_LENGTH)) 325 { 326 n=ssl3_read_n(s, SSL3_RT_HEADER_LENGTH, s->s3->rbuf.len, 0); 327 if (n <= 0) return(n); /* error or non-blocking */ 328 s->rstate=SSL_ST_READ_BODY; 329 330 p=s->packet; 331 332 /* Pull apart the header into the SSL3_RECORD */ 333 rr->type= *(p++); 334 ssl_major= *(p++); 335 ssl_minor= *(p++); 336 version=(ssl_major<<8)|ssl_minor; 337 n2s(p,rr->length); 338#if 0 339fprintf(stderr, "Record type=%d, Length=%d\n", rr->type, rr->length); 340#endif 341 342 /* Lets check version */ 343 if (!s->first_packet) 344 { 345 if (version != s->version) 346 { 347 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_WRONG_VERSION_NUMBER); 348 if ((s->version & 0xFF00) == (version & 0xFF00) && !s->enc_write_ctx && !s->write_hash) 349 /* Send back error using their minor version number :-) */ 350 s->version = (unsigned short)version; 351 al=SSL_AD_PROTOCOL_VERSION; 352 goto f_err; 353 } 354 } 355 356 if ((version>>8) != SSL3_VERSION_MAJOR) 357 { 358 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_WRONG_VERSION_NUMBER); 359 goto err; 360 } 361 362 if (rr->length > s->s3->rbuf.len - SSL3_RT_HEADER_LENGTH) 363 { 364 al=SSL_AD_RECORD_OVERFLOW; 365 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_PACKET_LENGTH_TOO_LONG); 366 goto f_err; 367 } 368 369 /* now s->rstate == SSL_ST_READ_BODY */ 370 } 371 372 /* s->rstate == SSL_ST_READ_BODY, get and decode the data */ 373 374 if (rr->length > s->packet_length-SSL3_RT_HEADER_LENGTH) 375 { 376 /* now s->packet_length == SSL3_RT_HEADER_LENGTH */ 377 i=rr->length; 378 n=ssl3_read_n(s,i,i,1); 379 if (n <= 0) return(n); /* error or non-blocking io */ 380 /* now n == rr->length, 381 * and s->packet_length == SSL3_RT_HEADER_LENGTH + rr->length */ 382 } 383 384 s->rstate=SSL_ST_READ_HEADER; /* set state for later operations */ 385 386 /* At this point, s->packet_length == SSL3_RT_HEADER_LNGTH + rr->length, 387 * and we have that many bytes in s->packet 388 */ 389 rr->input= &(s->packet[SSL3_RT_HEADER_LENGTH]); 390 391 /* ok, we can now read from 's->packet' data into 'rr' 392 * rr->input points at rr->length bytes, which 393 * need to be copied into rr->data by either 394 * the decryption or by the decompression 395 * When the data is 'copied' into the rr->data buffer, 396 * rr->input will be pointed at the new buffer */ 397 398 /* We now have - encrypted [ MAC [ compressed [ plain ] ] ] 399 * rr->length bytes of encrypted compressed stuff. */ 400 401 /* check is not needed I believe */ 402 if (rr->length > SSL3_RT_MAX_ENCRYPTED_LENGTH+extra) 403 { 404 al=SSL_AD_RECORD_OVERFLOW; 405 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_ENCRYPTED_LENGTH_TOO_LONG); 406 goto f_err; 407 } 408 409 /* decrypt in place in 'rr->input' */ 410 rr->data=rr->input; 411 412 enc_err = s->method->ssl3_enc->enc(s,0); 413 /* enc_err is: 414 * 0: (in non-constant time) if the record is publically invalid. 415 * 1: if the padding is valid 416 * -1: if the padding is invalid */ 417 if (enc_err == 0) 418 { 419 al=SSL_AD_DECRYPTION_FAILED; 420 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_BLOCK_CIPHER_PAD_IS_WRONG); 421 goto f_err; 422 } 423 424#ifdef TLS_DEBUG 425printf("dec %d\n",rr->length); 426{ unsigned int z; for (z=0; z<rr->length; z++) printf("%02X%c",rr->data[z],((z+1)%16)?' ':'\n'); } 427printf("\n"); 428#endif 429 430 /* r->length is now the compressed data plus mac */ 431 if ((sess != NULL) && 432 (s->enc_read_ctx != NULL) && 433 (EVP_MD_CTX_md(s->read_hash) != NULL)) 434 { 435 /* s->read_hash != NULL => mac_size != -1 */ 436 unsigned char *mac = NULL; 437 unsigned char mac_tmp[EVP_MAX_MD_SIZE]; 438 mac_size=EVP_MD_CTX_size(s->read_hash); 439 OPENSSL_assert(mac_size <= EVP_MAX_MD_SIZE); 440 441 /* kludge: *_cbc_remove_padding passes padding length in rr->type */ 442 orig_len = rr->length+((unsigned int)rr->type>>8); 443 444 /* orig_len is the length of the record before any padding was 445 * removed. This is public information, as is the MAC in use, 446 * therefore we can safely process the record in a different 447 * amount of time if it's too short to possibly contain a MAC. 448 */ 449 if (orig_len < mac_size || 450 /* CBC records must have a padding length byte too. */ 451 (EVP_CIPHER_CTX_mode(s->enc_read_ctx) == EVP_CIPH_CBC_MODE && 452 orig_len < mac_size+1)) 453 { 454 al=SSL_AD_DECODE_ERROR; 455 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_LENGTH_TOO_SHORT); 456 goto f_err; 457 } 458 459 if (EVP_CIPHER_CTX_mode(s->enc_read_ctx) == EVP_CIPH_CBC_MODE) 460 { 461 /* We update the length so that the TLS header bytes 462 * can be constructed correctly but we need to extract 463 * the MAC in constant time from within the record, 464 * without leaking the contents of the padding bytes. 465 * */ 466 mac = mac_tmp; 467 ssl3_cbc_copy_mac(mac_tmp, rr, mac_size, orig_len); 468 rr->length -= mac_size; 469 } 470 else 471 { 472 /* In this case there's no padding, so |orig_len| 473 * equals |rec->length| and we checked that there's 474 * enough bytes for |mac_size| above. */ 475 rr->length -= mac_size; 476 mac = &rr->data[rr->length]; 477 } 478 479 i=s->method->ssl3_enc->mac(s,md,0 /* not send */); 480 if (i < 0 || mac == NULL || CRYPTO_memcmp(md, mac, (size_t)mac_size) != 0) 481 enc_err = -1; 482 if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH+extra+mac_size) 483 enc_err = -1; 484 } 485 486 if (enc_err < 0) 487 { 488 /* A separate 'decryption_failed' alert was introduced with TLS 1.0, 489 * SSL 3.0 only has 'bad_record_mac'. But unless a decryption 490 * failure is directly visible from the ciphertext anyway, 491 * we should not reveal which kind of error occured -- this 492 * might become visible to an attacker (e.g. via a logfile) */ 493 al=SSL_AD_BAD_RECORD_MAC; 494 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_DECRYPTION_FAILED_OR_BAD_RECORD_MAC); 495 goto f_err; 496 } 497 498 /* r->length is now just compressed */ 499 if (s->expand != NULL) 500 { 501 if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH+extra) 502 { 503 al=SSL_AD_RECORD_OVERFLOW; 504 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_COMPRESSED_LENGTH_TOO_LONG); 505 goto f_err; 506 } 507 if (!ssl3_do_uncompress(s)) 508 { 509 al=SSL_AD_DECOMPRESSION_FAILURE; 510 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_BAD_DECOMPRESSION); 511 goto f_err; 512 } 513 } 514 515 if (rr->length > SSL3_RT_MAX_PLAIN_LENGTH+extra) 516 { 517 al=SSL_AD_RECORD_OVERFLOW; 518 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_DATA_LENGTH_TOO_LONG); 519 goto f_err; 520 } 521 522 rr->off=0; 523 /* So at this point the following is true 524 * ssl->s3->rrec.type is the type of record 525 * ssl->s3->rrec.length == number of bytes in record 526 * ssl->s3->rrec.off == offset to first valid byte 527 * ssl->s3->rrec.data == where to take bytes from, increment 528 * after use :-). 529 */ 530 531 /* we have pulled in a full packet so zero things */ 532 s->packet_length=0; 533 534 /* just read a 0 length packet */ 535 if (rr->length == 0) 536 { 537 empty_record_count++; 538 if (empty_record_count > MAX_EMPTY_RECORDS) 539 { 540 al=SSL_AD_UNEXPECTED_MESSAGE; 541 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_RECORD_TOO_SMALL); 542 goto f_err; 543 } 544 goto again; 545 } 546 547#if 0 548fprintf(stderr, "Ultimate Record type=%d, Length=%d\n", rr->type, rr->length); 549#endif 550 551 return(1); 552 553f_err: 554 ssl3_send_alert(s,SSL3_AL_FATAL,al); 555err: 556 return(ret); 557 } 558 559int ssl3_do_uncompress(SSL *ssl) 560 { 561#ifndef OPENSSL_NO_COMP 562 int i; 563 SSL3_RECORD *rr; 564 565 rr= &(ssl->s3->rrec); 566 i=COMP_expand_block(ssl->expand,rr->comp, 567 SSL3_RT_MAX_PLAIN_LENGTH,rr->data,(int)rr->length); 568 if (i < 0) 569 return(0); 570 else 571 rr->length=i; 572 rr->data=rr->comp; 573#endif 574 return(1); 575 } 576 577int ssl3_do_compress(SSL *ssl) 578 { 579#ifndef OPENSSL_NO_COMP 580 int i; 581 SSL3_RECORD *wr; 582 583 wr= &(ssl->s3->wrec); 584 i=COMP_compress_block(ssl->compress,wr->data, 585 SSL3_RT_MAX_COMPRESSED_LENGTH, 586 wr->input,(int)wr->length); 587 if (i < 0) 588 return(0); 589 else 590 wr->length=i; 591 592 wr->input=wr->data; 593#endif 594 return(1); 595 } 596 597/* Call this to write data in records of type 'type' 598 * It will return <= 0 if not all data has been sent or non-blocking IO. 599 */ 600int ssl3_write_bytes(SSL *s, int type, const void *buf_, int len) 601 { 602 const unsigned char *buf=buf_; 603 unsigned int n,nw; 604 int i,tot; 605 606 s->rwstate=SSL_NOTHING; 607 OPENSSL_assert(s->s3->wnum <= INT_MAX); 608 tot=s->s3->wnum; 609 s->s3->wnum=0; 610 611 if (SSL_in_init(s) && !s->in_handshake) 612 { 613 i=s->handshake_func(s); 614 if (i < 0) return(i); 615 if (i == 0) 616 { 617 SSLerr(SSL_F_SSL3_WRITE_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE); 618 return -1; 619 } 620 } 621 622 /* ensure that if we end up with a smaller value of data to write 623 * out than the the original len from a write which didn't complete 624 * for non-blocking I/O and also somehow ended up avoiding 625 * the check for this in ssl3_write_pending/SSL_R_BAD_WRITE_RETRY as 626 * it must never be possible to end up with (len-tot) as a large 627 * number that will then promptly send beyond the end of the users 628 * buffer ... so we trap and report the error in a way the user 629 * will notice 630 */ 631 if (len < tot) 632 { 633 SSLerr(SSL_F_SSL3_WRITE_BYTES,SSL_R_BAD_LENGTH); 634 return(-1); 635 } 636 637 638 n=(len-tot); 639 for (;;) 640 { 641 if (n > s->max_send_fragment) 642 nw=s->max_send_fragment; 643 else 644 nw=n; 645 646 i=do_ssl3_write(s, type, &(buf[tot]), nw, 0); 647 if (i <= 0) 648 { 649 s->s3->wnum=tot; 650 return i; 651 } 652 653 if ((i == (int)n) || 654 (type == SSL3_RT_APPLICATION_DATA && 655 (s->mode & SSL_MODE_ENABLE_PARTIAL_WRITE))) 656 { 657 /* next chunk of data should get another prepended empty fragment 658 * in ciphersuites with known-IV weakness: */ 659 s->s3->empty_fragment_done = 0; 660 661 return tot+i; 662 } 663 664 n-=i; 665 tot+=i; 666 } 667 } 668 669static int do_ssl3_write(SSL *s, int type, const unsigned char *buf, 670 unsigned int len, int create_empty_fragment) 671 { 672 unsigned char *p,*plen; 673 int i,mac_size,clear=0; 674 int prefix_len=0; 675 int eivlen; 676 long align=0; 677 SSL3_RECORD *wr; 678 SSL3_BUFFER *wb=&(s->s3->wbuf); 679 SSL_SESSION *sess; 680 681 682 /* first check if there is a SSL3_BUFFER still being written 683 * out. This will happen with non blocking IO */ 684 if (wb->left != 0) 685 return(ssl3_write_pending(s,type,buf,len)); 686 687 /* If we have an alert to send, lets send it */ 688 if (s->s3->alert_dispatch) 689 { 690 i=s->method->ssl_dispatch_alert(s); 691 if (i <= 0) 692 return(i); 693 /* if it went, fall through and send more stuff */ 694 } 695 696 if (wb->buf == NULL) 697 if (!ssl3_setup_write_buffer(s)) 698 return -1; 699 700 if (len == 0 && !create_empty_fragment) 701 return 0; 702 703 wr= &(s->s3->wrec); 704 sess=s->session; 705 706 if ( (sess == NULL) || 707 (s->enc_write_ctx == NULL) || 708 (EVP_MD_CTX_md(s->write_hash) == NULL)) 709 { 710#if 1 711 clear=s->enc_write_ctx?0:1; /* must be AEAD cipher */ 712#else 713 clear=1; 714#endif 715 mac_size=0; 716 } 717 else 718 { 719 mac_size=EVP_MD_CTX_size(s->write_hash); 720 if (mac_size < 0) 721 goto err; 722 } 723 724 /* 'create_empty_fragment' is true only when this function calls itself */ 725 if (!clear && !create_empty_fragment && !s->s3->empty_fragment_done) 726 { 727 /* countermeasure against known-IV weakness in CBC ciphersuites 728 * (see http://www.openssl.org/~bodo/tls-cbc.txt) */ 729 730 if (s->s3->need_empty_fragments && type == SSL3_RT_APPLICATION_DATA) 731 { 732 /* recursive function call with 'create_empty_fragment' set; 733 * this prepares and buffers the data for an empty fragment 734 * (these 'prefix_len' bytes are sent out later 735 * together with the actual payload) */ 736 prefix_len = do_ssl3_write(s, type, buf, 0, 1); 737 if (prefix_len <= 0) 738 goto err; 739 740 if (prefix_len > 741 (SSL3_RT_HEADER_LENGTH + SSL3_RT_SEND_MAX_ENCRYPTED_OVERHEAD)) 742 { 743 /* insufficient space */ 744 SSLerr(SSL_F_DO_SSL3_WRITE, ERR_R_INTERNAL_ERROR); 745 goto err; 746 } 747 } 748 749 s->s3->empty_fragment_done = 1; 750 } 751 752 if (create_empty_fragment) 753 { 754#if defined(SSL3_ALIGN_PAYLOAD) && SSL3_ALIGN_PAYLOAD!=0 755 /* extra fragment would be couple of cipher blocks, 756 * which would be multiple of SSL3_ALIGN_PAYLOAD, so 757 * if we want to align the real payload, then we can 758 * just pretent we simply have two headers. */ 759 align = (long)wb->buf + 2*SSL3_RT_HEADER_LENGTH; 760 align = (-align)&(SSL3_ALIGN_PAYLOAD-1); 761#endif 762 p = wb->buf + align; 763 wb->offset = align; 764 } 765 else if (prefix_len) 766 { 767 p = wb->buf + wb->offset + prefix_len; 768 } 769 else 770 { 771#if defined(SSL3_ALIGN_PAYLOAD) && SSL3_ALIGN_PAYLOAD!=0 772 align = (long)wb->buf + SSL3_RT_HEADER_LENGTH; 773 align = (-align)&(SSL3_ALIGN_PAYLOAD-1); 774#endif 775 p = wb->buf + align; 776 wb->offset = align; 777 } 778 779 /* write the header */ 780 781 *(p++)=type&0xff; 782 wr->type=type; 783 784 *(p++)=(s->version>>8); 785 /* Some servers hang if iniatial client hello is larger than 256 786 * bytes and record version number > TLS 1.0 787 */ 788 if (s->state == SSL3_ST_CW_CLNT_HELLO_B 789 && !s->renegotiate 790 && TLS1_get_version(s) > TLS1_VERSION) 791 *(p++) = 0x1; 792 else 793 *(p++)=s->version&0xff; 794 795 /* field where we are to write out packet length */ 796 plen=p; 797 p+=2; 798 /* Explicit IV length, block ciphers and TLS version 1.1 or later */ 799 if (s->enc_write_ctx && s->version >= TLS1_1_VERSION) 800 { 801 int mode = EVP_CIPHER_CTX_mode(s->enc_write_ctx); 802 if (mode == EVP_CIPH_CBC_MODE) 803 { 804 eivlen = EVP_CIPHER_CTX_iv_length(s->enc_write_ctx); 805 if (eivlen <= 1) 806 eivlen = 0; 807 } 808 /* Need explicit part of IV for GCM mode */ 809 else if (mode == EVP_CIPH_GCM_MODE) 810 eivlen = EVP_GCM_TLS_EXPLICIT_IV_LEN; 811 else 812 eivlen = 0; 813 } 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 /* we now 'read' from wr->input, wr->length bytes into 823 * wr->data */ 824 825 /* first we compress */ 826 if (s->compress != NULL) 827 { 828 if (!ssl3_do_compress(s)) 829 { 830 SSLerr(SSL_F_DO_SSL3_WRITE,SSL_R_COMPRESSION_FAILURE); 831 goto err; 832 } 833 } 834 else 835 { 836 memcpy(wr->data,wr->input,wr->length); 837 wr->input=wr->data; 838 } 839 840 /* we should still have the output to wr->data and the input 841 * from wr->input. Length should be wr->length. 842 * wr->data still points in the wb->buf */ 843 844 if (mac_size != 0) 845 { 846 if (s->method->ssl3_enc->mac(s,&(p[wr->length + eivlen]),1) < 0) 847 goto err; 848 wr->length+=mac_size; 849 } 850 851 wr->input=p; 852 wr->data=p; 853 854 if (eivlen) 855 { 856 /* if (RAND_pseudo_bytes(p, eivlen) <= 0) 857 goto err; */ 858 wr->length += eivlen; 859 } 860 861 /* ssl3_enc can only have an error on read */ 862 s->method->ssl3_enc->enc(s,1); 863 864 /* record length after mac and block padding */ 865 s2n(wr->length,plen); 866 867 /* we should now have 868 * wr->data pointing to the encrypted data, which is 869 * wr->length long */ 870 wr->type=type; /* not needed but helps for debugging */ 871 wr->length+=SSL3_RT_HEADER_LENGTH; 872 873 if (create_empty_fragment) 874 { 875 /* we are in a recursive call; 876 * just return the length, don't write out anything here 877 */ 878 return wr->length; 879 } 880 881 /* now let's set up wb */ 882 wb->left = prefix_len + wr->length; 883 884 /* memorize arguments so that ssl3_write_pending can detect bad write retries later */ 885 s->s3->wpend_tot=len; 886 s->s3->wpend_buf=buf; 887 s->s3->wpend_type=type; 888 s->s3->wpend_ret=len; 889 890 /* we now just need to write the buffer */ 891 return ssl3_write_pending(s,type,buf,len); 892err: 893 return -1; 894 } 895 896/* if s->s3->wbuf.left != 0, we need to call this */ 897int ssl3_write_pending(SSL *s, int type, const unsigned char *buf, 898 unsigned int len) 899 { 900 int i; 901 SSL3_BUFFER *wb=&(s->s3->wbuf); 902 903/* XXXX */ 904 if ((s->s3->wpend_tot > (int)len) 905 || ((s->s3->wpend_buf != buf) && 906 !(s->mode & SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER)) 907 || (s->s3->wpend_type != type)) 908 { 909 SSLerr(SSL_F_SSL3_WRITE_PENDING,SSL_R_BAD_WRITE_RETRY); 910 return(-1); 911 } 912 913 for (;;) 914 { 915 clear_sys_error(); 916 if (s->wbio != NULL) 917 { 918 s->rwstate=SSL_WRITING; 919 i=BIO_write(s->wbio, 920 (char *)&(wb->buf[wb->offset]), 921 (unsigned int)wb->left); 922 } 923 else 924 { 925 SSLerr(SSL_F_SSL3_WRITE_PENDING,SSL_R_BIO_NOT_SET); 926 i= -1; 927 } 928 if (i == wb->left) 929 { 930 wb->left=0; 931 wb->offset+=i; 932 if (s->mode & SSL_MODE_RELEASE_BUFFERS && 933 SSL_version(s) != DTLS1_VERSION && SSL_version(s) != DTLS1_BAD_VER) 934 ssl3_release_write_buffer(s); 935 s->rwstate=SSL_NOTHING; 936 return(s->s3->wpend_ret); 937 } 938 else if (i <= 0) { 939 if (s->version == DTLS1_VERSION || 940 s->version == DTLS1_BAD_VER) { 941 /* For DTLS, just drop it. That's kind of the whole 942 point in using a datagram service */ 943 wb->left = 0; 944 } 945 return(i); 946 } 947 wb->offset+=i; 948 wb->left-=i; 949 } 950 } 951 952/* Return up to 'len' payload bytes received in 'type' records. 953 * 'type' is one of the following: 954 * 955 * - SSL3_RT_HANDSHAKE (when ssl3_get_message calls us) 956 * - SSL3_RT_APPLICATION_DATA (when ssl3_read calls us) 957 * - 0 (during a shutdown, no data has to be returned) 958 * 959 * If we don't have stored data to work from, read a SSL/TLS record first 960 * (possibly multiple records if we still don't have anything to return). 961 * 962 * This function must handle any surprises the peer may have for us, such as 963 * Alert records (e.g. close_notify), ChangeCipherSpec records (not really 964 * a surprise, but handled as if it were), or renegotiation requests. 965 * Also if record payloads contain fragments too small to process, we store 966 * them until there is enough for the respective protocol (the record protocol 967 * may use arbitrary fragmentation and even interleaving): 968 * Change cipher spec protocol 969 * just 1 byte needed, no need for keeping anything stored 970 * Alert protocol 971 * 2 bytes needed (AlertLevel, AlertDescription) 972 * Handshake protocol 973 * 4 bytes needed (HandshakeType, uint24 length) -- we just have 974 * to detect unexpected Client Hello and Hello Request messages 975 * here, anything else is handled by higher layers 976 * Application data protocol 977 * none of our business 978 */ 979int ssl3_read_bytes(SSL *s, int type, unsigned char *buf, int len, int peek) 980 { 981 int al,i,j,ret; 982 unsigned int n; 983 SSL3_RECORD *rr; 984 void (*cb)(const SSL *ssl,int type2,int val)=NULL; 985 986 if (s->s3->rbuf.buf == NULL) /* Not initialized yet */ 987 if (!ssl3_setup_read_buffer(s)) 988 return(-1); 989 990 if ((type && (type != SSL3_RT_APPLICATION_DATA) && (type != SSL3_RT_HANDSHAKE)) || 991 (peek && (type != SSL3_RT_APPLICATION_DATA))) 992 { 993 SSLerr(SSL_F_SSL3_READ_BYTES, ERR_R_INTERNAL_ERROR); 994 return -1; 995 } 996 997 if ((type == SSL3_RT_HANDSHAKE) && (s->s3->handshake_fragment_len > 0)) 998 /* (partially) satisfy request from storage */ 999 { 1000 unsigned char *src = s->s3->handshake_fragment; 1001 unsigned char *dst = buf; 1002 unsigned int k; 1003 1004 /* peek == 0 */ 1005 n = 0; 1006 while ((len > 0) && (s->s3->handshake_fragment_len > 0)) 1007 { 1008 *dst++ = *src++; 1009 len--; s->s3->handshake_fragment_len--; 1010 n++; 1011 } 1012 /* move any remaining fragment bytes: */ 1013 for (k = 0; k < s->s3->handshake_fragment_len; k++) 1014 s->s3->handshake_fragment[k] = *src++; 1015 return n; 1016 } 1017 1018 /* Now s->s3->handshake_fragment_len == 0 if type == SSL3_RT_HANDSHAKE. */ 1019 1020 if (!s->in_handshake && SSL_in_init(s)) 1021 { 1022 /* type == SSL3_RT_APPLICATION_DATA */ 1023 i=s->handshake_func(s); 1024 if (i < 0) return(i); 1025 if (i == 0) 1026 { 1027 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE); 1028 return(-1); 1029 } 1030 } 1031start: 1032 s->rwstate=SSL_NOTHING; 1033 1034 /* s->s3->rrec.type - is the type of record 1035 * s->s3->rrec.data, - data 1036 * s->s3->rrec.off, - offset into 'data' for next read 1037 * s->s3->rrec.length, - number of bytes. */ 1038 rr = &(s->s3->rrec); 1039 1040 /* get new packet if necessary */ 1041 if ((rr->length == 0) || (s->rstate == SSL_ST_READ_BODY)) 1042 { 1043 ret=ssl3_get_record(s); 1044 if (ret <= 0) return(ret); 1045 } 1046 1047 /* we now have a packet which can be read and processed */ 1048 1049 if (s->s3->change_cipher_spec /* set when we receive ChangeCipherSpec, 1050 * reset by ssl3_get_finished */ 1051 && (rr->type != SSL3_RT_HANDSHAKE)) 1052 { 1053 al=SSL_AD_UNEXPECTED_MESSAGE; 1054 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_DATA_BETWEEN_CCS_AND_FINISHED); 1055 goto f_err; 1056 } 1057 1058 /* If the other end has shut down, throw anything we read away 1059 * (even in 'peek' mode) */ 1060 if (s->shutdown & SSL_RECEIVED_SHUTDOWN) 1061 { 1062 rr->length=0; 1063 s->rwstate=SSL_NOTHING; 1064 return(0); 1065 } 1066 1067 1068 if (type == rr->type) /* SSL3_RT_APPLICATION_DATA or SSL3_RT_HANDSHAKE */ 1069 { 1070 /* make sure that we are not getting application data when we 1071 * are doing a handshake for the first time */ 1072 if (SSL_in_init(s) && (type == SSL3_RT_APPLICATION_DATA) && 1073 (s->enc_read_ctx == NULL)) 1074 { 1075 al=SSL_AD_UNEXPECTED_MESSAGE; 1076 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_APP_DATA_IN_HANDSHAKE); 1077 goto f_err; 1078 } 1079 1080 if (len <= 0) return(len); 1081 1082 if ((unsigned int)len > rr->length) 1083 n = rr->length; 1084 else 1085 n = (unsigned int)len; 1086 1087 memcpy(buf,&(rr->data[rr->off]),n); 1088 if (!peek) 1089 { 1090 rr->length-=n; 1091 rr->off+=n; 1092 if (rr->length == 0) 1093 { 1094 s->rstate=SSL_ST_READ_HEADER; 1095 rr->off=0; 1096 if (s->mode & SSL_MODE_RELEASE_BUFFERS && s->s3->rbuf.left == 0) 1097 ssl3_release_read_buffer(s); 1098 } 1099 } 1100 return(n); 1101 } 1102 1103 1104 /* If we get here, then type != rr->type; if we have a handshake 1105 * message, then it was unexpected (Hello Request or Client Hello). */ 1106 1107 /* In case of record types for which we have 'fragment' storage, 1108 * fill that so that we can process the data at a fixed place. 1109 */ 1110 { 1111 unsigned int dest_maxlen = 0; 1112 unsigned char *dest = NULL; 1113 unsigned int *dest_len = NULL; 1114 1115 if (rr->type == SSL3_RT_HANDSHAKE) 1116 { 1117 dest_maxlen = sizeof s->s3->handshake_fragment; 1118 dest = s->s3->handshake_fragment; 1119 dest_len = &s->s3->handshake_fragment_len; 1120 } 1121 else if (rr->type == SSL3_RT_ALERT) 1122 { 1123 dest_maxlen = sizeof s->s3->alert_fragment; 1124 dest = s->s3->alert_fragment; 1125 dest_len = &s->s3->alert_fragment_len; 1126 } 1127#ifndef OPENSSL_NO_HEARTBEATS 1128 else if (rr->type == TLS1_RT_HEARTBEAT) 1129 { 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 { 1143 n = dest_maxlen - *dest_len; /* available space in 'dest' */ 1144 if (rr->length < n) 1145 n = rr->length; /* available bytes */ 1146 1147 /* now move 'n' bytes: */ 1148 while (n-- > 0) 1149 { 1150 dest[(*dest_len)++] = rr->data[rr->off++]; 1151 rr->length--; 1152 } 1153 1154 if (*dest_len < dest_maxlen) 1155 goto start; /* fragment was too small */ 1156 } 1157 } 1158 1159 /* s->s3->handshake_fragment_len == 4 iff rr->type == SSL3_RT_HANDSHAKE; 1160 * s->s3->alert_fragment_len == 2 iff rr->type == SSL3_RT_ALERT. 1161 * (Possibly rr is 'empty' now, i.e. rr->length may be 0.) */ 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 { 1169 s->s3->handshake_fragment_len = 0; 1170 1171 if ((s->s3->handshake_fragment[1] != 0) || 1172 (s->s3->handshake_fragment[2] != 0) || 1173 (s->s3->handshake_fragment[3] != 0)) 1174 { 1175 al=SSL_AD_DECODE_ERROR; 1176 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_BAD_HELLO_REQUEST); 1177 goto f_err; 1178 } 1179 1180 if (s->msg_callback) 1181 s->msg_callback(0, s->version, SSL3_RT_HANDSHAKE, s->s3->handshake_fragment, 4, s, 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 { 1187 ssl3_renegotiate(s); 1188 if (ssl3_renegotiate_check(s)) 1189 { 1190 i=s->handshake_func(s); 1191 if (i < 0) return(i); 1192 if (i == 0) 1193 { 1194 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE); 1195 return(-1); 1196 } 1197 1198 if (!(s->mode & SSL_MODE_AUTO_RETRY)) 1199 { 1200 if (s->s3->rbuf.left == 0) /* no read-ahead left? */ 1201 { 1202 BIO *bio; 1203 /* In the case where we try to read application data, 1204 * but we trigger an SSL handshake, we return -1 with 1205 * the retry option set. Otherwise renegotiation may 1206 * cause nasty problems in the blocking world */ 1207 s->rwstate=SSL_READING; 1208 bio=SSL_get_rbio(s); 1209 BIO_clear_retry_flags(bio); 1210 BIO_set_retry_read(bio); 1211 return(-1); 1212 } 1213 } 1214 } 1215 } 1216 /* we either finished a handshake or ignored the request, 1217 * now try again to obtain the (application) data we were asked for */ 1218 goto start; 1219 } 1220 /* If we are a server and get a client hello when renegotiation isn't 1221 * allowed send back a no renegotiation alert and carry on. 1222 * WARNING: experimental code, needs reviewing (steve) 1223 */ 1224 if (s->server && 1225 SSL_is_init_finished(s) && 1226 !s->s3->send_connection_binding && 1227 (s->version > SSL3_VERSION) && 1228 (s->s3->handshake_fragment_len >= 4) && 1229 (s->s3->handshake_fragment[0] == SSL3_MT_CLIENT_HELLO) && 1230 (s->session != NULL) && (s->session->cipher != NULL) && 1231 !(s->ctx->options & SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION)) 1232 1233 { 1234 /*s->s3->handshake_fragment_len = 0;*/ 1235 rr->length = 0; 1236 ssl3_send_alert(s,SSL3_AL_WARNING, SSL_AD_NO_RENEGOTIATION); 1237 goto start; 1238 } 1239 if (s->s3->alert_fragment_len >= 2) 1240 { 1241 int alert_level = s->s3->alert_fragment[0]; 1242 int alert_descr = s->s3->alert_fragment[1]; 1243 1244 s->s3->alert_fragment_len = 0; 1245 1246 if (s->msg_callback) 1247 s->msg_callback(0, s->version, SSL3_RT_ALERT, s->s3->alert_fragment, 2, s, s->msg_callback_arg); 1248 1249 if (s->info_callback != NULL) 1250 cb=s->info_callback; 1251 else if (s->ctx->info_callback != NULL) 1252 cb=s->ctx->info_callback; 1253 1254 if (cb != NULL) 1255 { 1256 j = (alert_level << 8) | alert_descr; 1257 cb(s, SSL_CB_READ_ALERT, j); 1258 } 1259 1260 if (alert_level == 1) /* warning */ 1261 { 1262 s->s3->warn_alert = alert_descr; 1263 if (alert_descr == SSL_AD_CLOSE_NOTIFY) 1264 { 1265 s->shutdown |= SSL_RECEIVED_SHUTDOWN; 1266 return(0); 1267 } 1268 /* This is a warning but we receive it if we requested 1269 * renegotiation and the peer denied it. Terminate with 1270 * a fatal alert because if application tried to 1271 * renegotiatie it presumably had a good reason and 1272 * expects it to succeed. 1273 * 1274 * In future we might have a renegotiation where we 1275 * don't care if the peer refused it where we carry on. 1276 */ 1277 else if (alert_descr == SSL_AD_NO_RENEGOTIATION) 1278 { 1279 al = SSL_AD_HANDSHAKE_FAILURE; 1280 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_NO_RENEGOTIATION); 1281 goto f_err; 1282 } 1283#ifdef SSL_AD_MISSING_SRP_USERNAME 1284 else if (alert_descr == SSL_AD_MISSING_SRP_USERNAME) 1285 return(0); 1286#endif 1287 } 1288 else if (alert_level == 2) /* fatal */ 1289 { 1290 char tmp[16]; 1291 1292 s->rwstate=SSL_NOTHING; 1293 s->s3->fatal_alert = alert_descr; 1294 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_AD_REASON_OFFSET + alert_descr); 1295 BIO_snprintf(tmp,sizeof tmp,"%d",alert_descr); 1296 ERR_add_error_data(2,"SSL alert number ",tmp); 1297 s->shutdown|=SSL_RECEIVED_SHUTDOWN; 1298 SSL_CTX_remove_session(s->ctx,s->session); 1299 return(0); 1300 } 1301 else 1302 { 1303 al=SSL_AD_ILLEGAL_PARAMETER; 1304 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNKNOWN_ALERT_TYPE); 1305 goto f_err; 1306 } 1307 1308 goto start; 1309 } 1310 1311 if (s->shutdown & SSL_SENT_SHUTDOWN) /* but we have not received a shutdown */ 1312 { 1313 s->rwstate=SSL_NOTHING; 1314 rr->length=0; 1315 return(0); 1316 } 1317 1318 if (rr->type == SSL3_RT_CHANGE_CIPHER_SPEC) 1319 { 1320 /* 'Change Cipher Spec' is just a single byte, so we know 1321 * exactly what the record payload has to look like */ 1322 if ( (rr->length != 1) || (rr->off != 0) || 1323 (rr->data[0] != SSL3_MT_CCS)) 1324 { 1325 al=SSL_AD_ILLEGAL_PARAMETER; 1326 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_BAD_CHANGE_CIPHER_SPEC); 1327 goto f_err; 1328 } 1329 1330 /* Check we have a cipher to change to */ 1331 if (s->s3->tmp.new_cipher == NULL) 1332 { 1333 al=SSL_AD_UNEXPECTED_MESSAGE; 1334 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_CCS_RECEIVED_EARLY); 1335 goto f_err; 1336 } 1337 1338 if (!(s->s3->flags & SSL3_FLAGS_CCS_OK)) 1339 { 1340 al=SSL_AD_UNEXPECTED_MESSAGE; 1341 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_CCS_RECEIVED_EARLY); 1342 goto f_err; 1343 } 1344 1345 s->s3->flags &= ~SSL3_FLAGS_CCS_OK; 1346 1347 rr->length=0; 1348 1349 if (s->msg_callback) 1350 s->msg_callback(0, s->version, SSL3_RT_CHANGE_CIPHER_SPEC, rr->data, 1, s, s->msg_callback_arg); 1351 1352 s->s3->change_cipher_spec=1; 1353 if (!ssl3_do_change_cipher_spec(s)) 1354 goto err; 1355 else 1356 goto start; 1357 } 1358 1359 /* Unexpected handshake message (Client Hello, or protocol violation) */ 1360 if ((s->s3->handshake_fragment_len >= 4) && !s->in_handshake) 1361 { 1362 if (((s->state&SSL_ST_MASK) == SSL_ST_OK) && 1363 !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS)) 1364 { 1365#if 0 /* worked only because C operator preferences are not as expected (and 1366 * because this is not really needed for clients except for detecting 1367 * protocol violations): */ 1368 s->state=SSL_ST_BEFORE|(s->server) 1369 ?SSL_ST_ACCEPT 1370 :SSL_ST_CONNECT; 1371#else 1372 s->state = s->server ? SSL_ST_ACCEPT : SSL_ST_CONNECT; 1373#endif 1374 s->renegotiate=1; 1375 s->new_session=1; 1376 } 1377 i=s->handshake_func(s); 1378 if (i < 0) return(i); 1379 if (i == 0) 1380 { 1381 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE); 1382 return(-1); 1383 } 1384 1385 if (!(s->mode & SSL_MODE_AUTO_RETRY)) 1386 { 1387 if (s->s3->rbuf.left == 0) /* no read-ahead left? */ 1388 { 1389 BIO *bio; 1390 /* In the case where we try to read application data, 1391 * but we trigger an SSL handshake, we return -1 with 1392 * the retry option set. Otherwise renegotiation may 1393 * cause nasty problems in the blocking world */ 1394 s->rwstate=SSL_READING; 1395 bio=SSL_get_rbio(s); 1396 BIO_clear_retry_flags(bio); 1397 BIO_set_retry_read(bio); 1398 return(-1); 1399 } 1400 } 1401 goto start; 1402 } 1403 1404 switch (rr->type) 1405 { 1406 default: 1407#ifndef OPENSSL_NO_TLS 1408 /* TLS up to v1.1 just ignores unknown message types: 1409 * TLS v1.2 give an unexpected message alert. 1410 */ 1411 if (s->version >= TLS1_VERSION && s->version <= TLS1_1_VERSION) 1412 { 1413 rr->length = 0; 1414 goto start; 1415 } 1416#endif 1417 al=SSL_AD_UNEXPECTED_MESSAGE; 1418 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNEXPECTED_RECORD); 1419 goto f_err; 1420 case SSL3_RT_CHANGE_CIPHER_SPEC: 1421 case SSL3_RT_ALERT: 1422 case SSL3_RT_HANDSHAKE: 1423 /* we already handled all of these, with the possible exception 1424 * of SSL3_RT_HANDSHAKE when s->in_handshake is set, but that 1425 * should not happen when type != rr->type */ 1426 al=SSL_AD_UNEXPECTED_MESSAGE; 1427 SSLerr(SSL_F_SSL3_READ_BYTES,ERR_R_INTERNAL_ERROR); 1428 goto f_err; 1429 case SSL3_RT_APPLICATION_DATA: 1430 /* At this point, we were expecting handshake data, 1431 * but have application data. If the library was 1432 * running inside ssl3_read() (i.e. in_read_app_data 1433 * is set) and it makes sense to read application data 1434 * at this point (session renegotiation not yet started), 1435 * we will indulge it. 1436 */ 1437 if (s->s3->in_read_app_data && 1438 (s->s3->total_renegotiations != 0) && 1439 (( 1440 (s->state & SSL_ST_CONNECT) && 1441 (s->state >= SSL3_ST_CW_CLNT_HELLO_A) && 1442 (s->state <= SSL3_ST_CR_SRVR_HELLO_A) 1443 ) || ( 1444 (s->state & SSL_ST_ACCEPT) && 1445 (s->state <= SSL3_ST_SW_HELLO_REQ_A) && 1446 (s->state >= SSL3_ST_SR_CLNT_HELLO_A) 1447 ) 1448 )) 1449 { 1450 s->s3->in_read_app_data=2; 1451 return(-1); 1452 } 1453 else 1454 { 1455 al=SSL_AD_UNEXPECTED_MESSAGE; 1456 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNEXPECTED_RECORD); 1457 goto f_err; 1458 } 1459 } 1460 /* not reached */ 1461 1462f_err: 1463 ssl3_send_alert(s,SSL3_AL_FATAL,al); 1464err: 1465 return(-1); 1466 } 1467 1468int ssl3_do_change_cipher_spec(SSL *s) 1469 { 1470 int i; 1471 const char *sender; 1472 int slen; 1473 1474 if (s->state & SSL_ST_ACCEPT) 1475 i=SSL3_CHANGE_CIPHER_SERVER_READ; 1476 else 1477 i=SSL3_CHANGE_CIPHER_CLIENT_READ; 1478 1479 if (s->s3->tmp.key_block == NULL) 1480 { 1481 if (s->session == NULL || s->session->master_key_length == 0) 1482 { 1483 /* might happen if dtls1_read_bytes() calls this */ 1484 SSLerr(SSL_F_SSL3_DO_CHANGE_CIPHER_SPEC,SSL_R_CCS_RECEIVED_EARLY); 1485 return (0); 1486 } 1487 1488 s->session->cipher=s->s3->tmp.new_cipher; 1489 if (!s->method->ssl3_enc->setup_key_block(s)) return(0); 1490 } 1491 1492 if (!s->method->ssl3_enc->change_cipher_state(s,i)) 1493 return(0); 1494 1495 /* we have to record the message digest at 1496 * this point so we can get it before we read 1497 * the finished message */ 1498 if (s->state & SSL_ST_CONNECT) 1499 { 1500 sender=s->method->ssl3_enc->server_finished_label; 1501 slen=s->method->ssl3_enc->server_finished_label_len; 1502 } 1503 else 1504 { 1505 sender=s->method->ssl3_enc->client_finished_label; 1506 slen=s->method->ssl3_enc->client_finished_label_len; 1507 } 1508 1509 i = s->method->ssl3_enc->final_finish_mac(s, 1510 sender,slen,s->s3->tmp.peer_finish_md); 1511 if (i == 0) 1512 { 1513 SSLerr(SSL_F_SSL3_DO_CHANGE_CIPHER_SPEC, ERR_R_INTERNAL_ERROR); 1514 return 0; 1515 } 1516 s->s3->tmp.peer_finish_md_len = i; 1517 1518 return(1); 1519 } 1520 1521int ssl3_send_alert(SSL *s, int level, int desc) 1522 { 1523 /* Map tls/ssl alert value to correct one */ 1524 desc=s->method->ssl3_enc->alert_value(desc); 1525 if (s->version == SSL3_VERSION && desc == SSL_AD_PROTOCOL_VERSION) 1526 desc = SSL_AD_HANDSHAKE_FAILURE; /* SSL 3.0 does not have protocol_version alerts */ 1527 if (desc < 0) return -1; 1528 /* If a fatal one, remove from cache */ 1529 if ((level == 2) && (s->session != NULL)) 1530 SSL_CTX_remove_session(s->ctx,s->session); 1531 1532 s->s3->alert_dispatch=1; 1533 s->s3->send_alert[0]=level; 1534 s->s3->send_alert[1]=desc; 1535 if (s->s3->wbuf.left == 0) /* data still being written out? */ 1536 return s->method->ssl_dispatch_alert(s); 1537 /* else data is still being written out, we will get written 1538 * some time in the future */ 1539 return -1; 1540 } 1541 1542int ssl3_dispatch_alert(SSL *s) 1543 { 1544 int i,j; 1545 void (*cb)(const SSL *ssl,int type,int val)=NULL; 1546 1547 s->s3->alert_dispatch=0; 1548 i = do_ssl3_write(s, SSL3_RT_ALERT, &s->s3->send_alert[0], 2, 0); 1549 if (i <= 0) 1550 { 1551 s->s3->alert_dispatch=1; 1552 } 1553 else 1554 { 1555 /* Alert sent to BIO. If it is important, flush it now. 1556 * If the message does not get sent due to non-blocking IO, 1557 * we will not worry too much. */ 1558 if (s->s3->send_alert[0] == SSL3_AL_FATAL) 1559 (void)BIO_flush(s->wbio); 1560 1561 if (s->msg_callback) 1562 s->msg_callback(1, s->version, SSL3_RT_ALERT, s->s3->send_alert, 2, s, s->msg_callback_arg); 1563 1564 if (s->info_callback != NULL) 1565 cb=s->info_callback; 1566 else if (s->ctx->info_callback != NULL) 1567 cb=s->ctx->info_callback; 1568 1569 if (cb != NULL) 1570 { 1571 j=(s->s3->send_alert[0]<<8)|s->s3->send_alert[1]; 1572 cb(s,SSL_CB_WRITE_ALERT,j); 1573 } 1574 } 1575 return(i); 1576 } 1577