s3_pkt.c revision 273149
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 && n > left) 187 n = left; 188 } 189 190 /* if there is enough in the buffer from a previous read, take some */ 191 if (left >= n) 192 { 193 s->packet_length+=n; 194 rb->left=left-n; 195 rb->offset+=n; 196 return(n); 197 } 198 199 /* else we need to read more data */ 200 201 len = s->packet_length; 202 pkt = rb->buf+align; 203 /* Move any available bytes to front of buffer: 204 * 'len' bytes already pointed to by 'packet', 205 * 'left' extra ones at the end */ 206 if (s->packet != pkt) /* len > 0 */ 207 { 208 memmove(pkt, s->packet, len+left); 209 s->packet = pkt; 210 rb->offset = len + align; 211 } 212 213 if (n > (int)(rb->len - rb->offset)) /* does not happen */ 214 { 215 SSLerr(SSL_F_SSL3_READ_N,ERR_R_INTERNAL_ERROR); 216 return -1; 217 } 218 219 if (!s->read_ahead) 220 /* ignore max parameter */ 221 max = n; 222 else 223 { 224 if (max < n) 225 max = n; 226 if (max > (int)(rb->len - rb->offset)) 227 max = rb->len - rb->offset; 228 } 229 230 while (left < n) 231 { 232 /* Now we have len+left bytes at the front of s->s3->rbuf.buf 233 * and need to read in more until we have len+n (up to 234 * len+max if possible) */ 235 236 clear_sys_error(); 237 if (s->rbio != NULL) 238 { 239 s->rwstate=SSL_READING; 240 i=BIO_read(s->rbio,pkt+len+left, max-left); 241 } 242 else 243 { 244 SSLerr(SSL_F_SSL3_READ_N,SSL_R_READ_BIO_NOT_SET); 245 i = -1; 246 } 247 248 if (i <= 0) 249 { 250 rb->left = left; 251 if (s->mode & SSL_MODE_RELEASE_BUFFERS && 252 SSL_version(s) != DTLS1_VERSION && SSL_version(s) != DTLS1_BAD_VER) 253 if (len+left == 0) 254 ssl3_release_read_buffer(s); 255 return(i); 256 } 257 left+=i; 258 /* reads should *never* span multiple packets for DTLS because 259 * the underlying transport protocol is message oriented as opposed 260 * to byte oriented as in the TLS case. */ 261 if (SSL_version(s) == DTLS1_VERSION || SSL_version(s) == DTLS1_BAD_VER) 262 { 263 if (n > left) 264 n = left; /* makes the while condition false */ 265 } 266 } 267 268 /* done reading, now the book-keeping */ 269 rb->offset += n; 270 rb->left = left - n; 271 s->packet_length += n; 272 s->rwstate=SSL_NOTHING; 273 return(n); 274 } 275 276/* MAX_EMPTY_RECORDS defines the number of consecutive, empty records that will 277 * be processed per call to ssl3_get_record. Without this limit an attacker 278 * could send empty records at a faster rate than we can process and cause 279 * ssl3_get_record to loop forever. */ 280#define MAX_EMPTY_RECORDS 32 281 282/* Call this to get a new input record. 283 * It will return <= 0 if more data is needed, normally due to an error 284 * or non-blocking IO. 285 * When it finishes, one packet has been decoded and can be found in 286 * ssl->s3->rrec.type - is the type of record 287 * ssl->s3->rrec.data, - data 288 * ssl->s3->rrec.length, - number of bytes 289 */ 290/* used only by ssl3_read_bytes */ 291static int ssl3_get_record(SSL *s) 292 { 293 int ssl_major,ssl_minor,al; 294 int enc_err,n,i,ret= -1; 295 SSL3_RECORD *rr; 296 SSL_SESSION *sess; 297 unsigned char *p; 298 unsigned char md[EVP_MAX_MD_SIZE]; 299 short version; 300 unsigned mac_size, orig_len; 301 size_t extra; 302 unsigned empty_record_count = 0; 303 304 rr= &(s->s3->rrec); 305 sess=s->session; 306 307 if (s->options & SSL_OP_MICROSOFT_BIG_SSLV3_BUFFER) 308 extra=SSL3_RT_MAX_EXTRA; 309 else 310 extra=0; 311 if (extra && !s->s3->init_extra) 312 { 313 /* An application error: SLS_OP_MICROSOFT_BIG_SSLV3_BUFFER 314 * set after ssl3_setup_buffers() was done */ 315 SSLerr(SSL_F_SSL3_GET_RECORD, ERR_R_INTERNAL_ERROR); 316 return -1; 317 } 318 319again: 320 /* check if we have the header */ 321 if ( (s->rstate != SSL_ST_READ_BODY) || 322 (s->packet_length < SSL3_RT_HEADER_LENGTH)) 323 { 324 n=ssl3_read_n(s, SSL3_RT_HEADER_LENGTH, s->s3->rbuf.len, 0); 325 if (n <= 0) return(n); /* error or non-blocking */ 326 s->rstate=SSL_ST_READ_BODY; 327 328 p=s->packet; 329 330 /* Pull apart the header into the SSL3_RECORD */ 331 rr->type= *(p++); 332 ssl_major= *(p++); 333 ssl_minor= *(p++); 334 version=(ssl_major<<8)|ssl_minor; 335 n2s(p,rr->length); 336#if 0 337fprintf(stderr, "Record type=%d, Length=%d\n", rr->type, rr->length); 338#endif 339 340 /* Lets check version */ 341 if (!s->first_packet) 342 { 343 if (version != s->version) 344 { 345 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_WRONG_VERSION_NUMBER); 346 if ((s->version & 0xFF00) == (version & 0xFF00) && !s->enc_write_ctx && !s->write_hash) 347 /* Send back error using their minor version number :-) */ 348 s->version = (unsigned short)version; 349 al=SSL_AD_PROTOCOL_VERSION; 350 goto f_err; 351 } 352 } 353 354 if ((version>>8) != SSL3_VERSION_MAJOR) 355 { 356 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_WRONG_VERSION_NUMBER); 357 goto err; 358 } 359 360 if (rr->length > s->s3->rbuf.len - SSL3_RT_HEADER_LENGTH) 361 { 362 al=SSL_AD_RECORD_OVERFLOW; 363 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_PACKET_LENGTH_TOO_LONG); 364 goto f_err; 365 } 366 367 /* now s->rstate == SSL_ST_READ_BODY */ 368 } 369 370 /* s->rstate == SSL_ST_READ_BODY, get and decode the data */ 371 372 if (rr->length > s->packet_length-SSL3_RT_HEADER_LENGTH) 373 { 374 /* now s->packet_length == SSL3_RT_HEADER_LENGTH */ 375 i=rr->length; 376 n=ssl3_read_n(s,i,i,1); 377 if (n <= 0) return(n); /* error or non-blocking io */ 378 /* now n == rr->length, 379 * and s->packet_length == SSL3_RT_HEADER_LENGTH + rr->length */ 380 } 381 382 s->rstate=SSL_ST_READ_HEADER; /* set state for later operations */ 383 384 /* At this point, s->packet_length == SSL3_RT_HEADER_LNGTH + rr->length, 385 * and we have that many bytes in s->packet 386 */ 387 rr->input= &(s->packet[SSL3_RT_HEADER_LENGTH]); 388 389 /* ok, we can now read from 's->packet' data into 'rr' 390 * rr->input points at rr->length bytes, which 391 * need to be copied into rr->data by either 392 * the decryption or by the decompression 393 * When the data is 'copied' into the rr->data buffer, 394 * rr->input will be pointed at the new buffer */ 395 396 /* We now have - encrypted [ MAC [ compressed [ plain ] ] ] 397 * rr->length bytes of encrypted compressed stuff. */ 398 399 /* check is not needed I believe */ 400 if (rr->length > SSL3_RT_MAX_ENCRYPTED_LENGTH+extra) 401 { 402 al=SSL_AD_RECORD_OVERFLOW; 403 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_ENCRYPTED_LENGTH_TOO_LONG); 404 goto f_err; 405 } 406 407 /* decrypt in place in 'rr->input' */ 408 rr->data=rr->input; 409 410 enc_err = s->method->ssl3_enc->enc(s,0); 411 /* enc_err is: 412 * 0: (in non-constant time) if the record is publically invalid. 413 * 1: if the padding is valid 414 * -1: if the padding is invalid */ 415 if (enc_err == 0) 416 { 417 al=SSL_AD_DECRYPTION_FAILED; 418 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_BLOCK_CIPHER_PAD_IS_WRONG); 419 goto f_err; 420 } 421 422#ifdef TLS_DEBUG 423printf("dec %d\n",rr->length); 424{ unsigned int z; for (z=0; z<rr->length; z++) printf("%02X%c",rr->data[z],((z+1)%16)?' ':'\n'); } 425printf("\n"); 426#endif 427 428 /* r->length is now the compressed data plus mac */ 429 if ((sess != NULL) && 430 (s->enc_read_ctx != NULL) && 431 (EVP_MD_CTX_md(s->read_hash) != NULL)) 432 { 433 /* s->read_hash != NULL => mac_size != -1 */ 434 unsigned char *mac = NULL; 435 unsigned char mac_tmp[EVP_MAX_MD_SIZE]; 436 mac_size=EVP_MD_CTX_size(s->read_hash); 437 OPENSSL_assert(mac_size <= EVP_MAX_MD_SIZE); 438 439 /* kludge: *_cbc_remove_padding passes padding length in rr->type */ 440 orig_len = rr->length+((unsigned int)rr->type>>8); 441 442 /* orig_len is the length of the record before any padding was 443 * removed. This is public information, as is the MAC in use, 444 * therefore we can safely process the record in a different 445 * amount of time if it's too short to possibly contain a MAC. 446 */ 447 if (orig_len < mac_size || 448 /* CBC records must have a padding length byte too. */ 449 (EVP_CIPHER_CTX_mode(s->enc_read_ctx) == EVP_CIPH_CBC_MODE && 450 orig_len < mac_size+1)) 451 { 452 al=SSL_AD_DECODE_ERROR; 453 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_LENGTH_TOO_SHORT); 454 goto f_err; 455 } 456 457 if (EVP_CIPHER_CTX_mode(s->enc_read_ctx) == EVP_CIPH_CBC_MODE) 458 { 459 /* We update the length so that the TLS header bytes 460 * can be constructed correctly but we need to extract 461 * the MAC in constant time from within the record, 462 * without leaking the contents of the padding bytes. 463 * */ 464 mac = mac_tmp; 465 ssl3_cbc_copy_mac(mac_tmp, rr, mac_size, orig_len); 466 rr->length -= mac_size; 467 } 468 else 469 { 470 /* In this case there's no padding, so |orig_len| 471 * equals |rec->length| and we checked that there's 472 * enough bytes for |mac_size| above. */ 473 rr->length -= mac_size; 474 mac = &rr->data[rr->length]; 475 } 476 477 i=s->method->ssl3_enc->mac(s,md,0 /* not send */); 478 if (i < 0 || mac == NULL || CRYPTO_memcmp(md, mac, (size_t)mac_size) != 0) 479 enc_err = -1; 480 if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH+extra+mac_size) 481 enc_err = -1; 482 } 483 484 if (enc_err < 0) 485 { 486 /* A separate 'decryption_failed' alert was introduced with TLS 1.0, 487 * SSL 3.0 only has 'bad_record_mac'. But unless a decryption 488 * failure is directly visible from the ciphertext anyway, 489 * we should not reveal which kind of error occured -- this 490 * might become visible to an attacker (e.g. via a logfile) */ 491 al=SSL_AD_BAD_RECORD_MAC; 492 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_DECRYPTION_FAILED_OR_BAD_RECORD_MAC); 493 goto f_err; 494 } 495 496 /* r->length is now just compressed */ 497 if (s->expand != NULL) 498 { 499 if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH+extra) 500 { 501 al=SSL_AD_RECORD_OVERFLOW; 502 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_COMPRESSED_LENGTH_TOO_LONG); 503 goto f_err; 504 } 505 if (!ssl3_do_uncompress(s)) 506 { 507 al=SSL_AD_DECOMPRESSION_FAILURE; 508 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_BAD_DECOMPRESSION); 509 goto f_err; 510 } 511 } 512 513 if (rr->length > SSL3_RT_MAX_PLAIN_LENGTH+extra) 514 { 515 al=SSL_AD_RECORD_OVERFLOW; 516 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_DATA_LENGTH_TOO_LONG); 517 goto f_err; 518 } 519 520 rr->off=0; 521 /* So at this point the following is true 522 * ssl->s3->rrec.type is the type of record 523 * ssl->s3->rrec.length == number of bytes in record 524 * ssl->s3->rrec.off == offset to first valid byte 525 * ssl->s3->rrec.data == where to take bytes from, increment 526 * after use :-). 527 */ 528 529 /* we have pulled in a full packet so zero things */ 530 s->packet_length=0; 531 532 /* just read a 0 length packet */ 533 if (rr->length == 0) 534 { 535 empty_record_count++; 536 if (empty_record_count > MAX_EMPTY_RECORDS) 537 { 538 al=SSL_AD_UNEXPECTED_MESSAGE; 539 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_RECORD_TOO_SMALL); 540 goto f_err; 541 } 542 goto again; 543 } 544 545#if 0 546fprintf(stderr, "Ultimate Record type=%d, Length=%d\n", rr->type, rr->length); 547#endif 548 549 return(1); 550 551f_err: 552 ssl3_send_alert(s,SSL3_AL_FATAL,al); 553err: 554 return(ret); 555 } 556 557int ssl3_do_uncompress(SSL *ssl) 558 { 559#ifndef OPENSSL_NO_COMP 560 int i; 561 SSL3_RECORD *rr; 562 563 rr= &(ssl->s3->rrec); 564 i=COMP_expand_block(ssl->expand,rr->comp, 565 SSL3_RT_MAX_PLAIN_LENGTH,rr->data,(int)rr->length); 566 if (i < 0) 567 return(0); 568 else 569 rr->length=i; 570 rr->data=rr->comp; 571#endif 572 return(1); 573 } 574 575int ssl3_do_compress(SSL *ssl) 576 { 577#ifndef OPENSSL_NO_COMP 578 int i; 579 SSL3_RECORD *wr; 580 581 wr= &(ssl->s3->wrec); 582 i=COMP_compress_block(ssl->compress,wr->data, 583 SSL3_RT_MAX_COMPRESSED_LENGTH, 584 wr->input,(int)wr->length); 585 if (i < 0) 586 return(0); 587 else 588 wr->length=i; 589 590 wr->input=wr->data; 591#endif 592 return(1); 593 } 594 595/* Call this to write data in records of type 'type' 596 * It will return <= 0 if not all data has been sent or non-blocking IO. 597 */ 598int ssl3_write_bytes(SSL *s, int type, const void *buf_, int len) 599 { 600 const unsigned char *buf=buf_; 601 unsigned int n,nw; 602 int i,tot; 603 604 s->rwstate=SSL_NOTHING; 605 OPENSSL_assert(s->s3->wnum <= INT_MAX); 606 tot=s->s3->wnum; 607 s->s3->wnum=0; 608 609 if (SSL_in_init(s) && !s->in_handshake) 610 { 611 i=s->handshake_func(s); 612 if (i < 0) return(i); 613 if (i == 0) 614 { 615 SSLerr(SSL_F_SSL3_WRITE_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE); 616 return -1; 617 } 618 } 619 620 /* ensure that if we end up with a smaller value of data to write 621 * out than the the original len from a write which didn't complete 622 * for non-blocking I/O and also somehow ended up avoiding 623 * the check for this in ssl3_write_pending/SSL_R_BAD_WRITE_RETRY as 624 * it must never be possible to end up with (len-tot) as a large 625 * number that will then promptly send beyond the end of the users 626 * buffer ... so we trap and report the error in a way the user 627 * will notice 628 */ 629 if (len < tot) 630 { 631 SSLerr(SSL_F_SSL3_WRITE_BYTES,SSL_R_BAD_LENGTH); 632 return(-1); 633 } 634 635 636 n=(len-tot); 637 for (;;) 638 { 639 if (n > s->max_send_fragment) 640 nw=s->max_send_fragment; 641 else 642 nw=n; 643 644 i=do_ssl3_write(s, type, &(buf[tot]), nw, 0); 645 if (i <= 0) 646 { 647 s->s3->wnum=tot; 648 return i; 649 } 650 651 if ((i == (int)n) || 652 (type == SSL3_RT_APPLICATION_DATA && 653 (s->mode & SSL_MODE_ENABLE_PARTIAL_WRITE))) 654 { 655 /* next chunk of data should get another prepended empty fragment 656 * in ciphersuites with known-IV weakness: */ 657 s->s3->empty_fragment_done = 0; 658 659 return tot+i; 660 } 661 662 n-=i; 663 tot+=i; 664 } 665 } 666 667static int do_ssl3_write(SSL *s, int type, const unsigned char *buf, 668 unsigned int len, int create_empty_fragment) 669 { 670 unsigned char *p,*plen; 671 int i,mac_size,clear=0; 672 int prefix_len=0; 673 int eivlen; 674 long align=0; 675 SSL3_RECORD *wr; 676 SSL3_BUFFER *wb=&(s->s3->wbuf); 677 SSL_SESSION *sess; 678 679 680 /* first check if there is a SSL3_BUFFER still being written 681 * out. This will happen with non blocking IO */ 682 if (wb->left != 0) 683 return(ssl3_write_pending(s,type,buf,len)); 684 685 /* If we have an alert to send, lets send it */ 686 if (s->s3->alert_dispatch) 687 { 688 i=s->method->ssl_dispatch_alert(s); 689 if (i <= 0) 690 return(i); 691 /* if it went, fall through and send more stuff */ 692 } 693 694 if (wb->buf == NULL) 695 if (!ssl3_setup_write_buffer(s)) 696 return -1; 697 698 if (len == 0 && !create_empty_fragment) 699 return 0; 700 701 wr= &(s->s3->wrec); 702 sess=s->session; 703 704 if ( (sess == NULL) || 705 (s->enc_write_ctx == NULL) || 706 (EVP_MD_CTX_md(s->write_hash) == NULL)) 707 { 708#if 1 709 clear=s->enc_write_ctx?0:1; /* must be AEAD cipher */ 710#else 711 clear=1; 712#endif 713 mac_size=0; 714 } 715 else 716 { 717 mac_size=EVP_MD_CTX_size(s->write_hash); 718 if (mac_size < 0) 719 goto err; 720 } 721 722 /* 'create_empty_fragment' is true only when this function calls itself */ 723 if (!clear && !create_empty_fragment && !s->s3->empty_fragment_done) 724 { 725 /* countermeasure against known-IV weakness in CBC ciphersuites 726 * (see http://www.openssl.org/~bodo/tls-cbc.txt) */ 727 728 if (s->s3->need_empty_fragments && type == SSL3_RT_APPLICATION_DATA) 729 { 730 /* recursive function call with 'create_empty_fragment' set; 731 * this prepares and buffers the data for an empty fragment 732 * (these 'prefix_len' bytes are sent out later 733 * together with the actual payload) */ 734 prefix_len = do_ssl3_write(s, type, buf, 0, 1); 735 if (prefix_len <= 0) 736 goto err; 737 738 if (prefix_len > 739 (SSL3_RT_HEADER_LENGTH + SSL3_RT_SEND_MAX_ENCRYPTED_OVERHEAD)) 740 { 741 /* insufficient space */ 742 SSLerr(SSL_F_DO_SSL3_WRITE, ERR_R_INTERNAL_ERROR); 743 goto err; 744 } 745 } 746 747 s->s3->empty_fragment_done = 1; 748 } 749 750 if (create_empty_fragment) 751 { 752#if defined(SSL3_ALIGN_PAYLOAD) && SSL3_ALIGN_PAYLOAD!=0 753 /* extra fragment would be couple of cipher blocks, 754 * which would be multiple of SSL3_ALIGN_PAYLOAD, so 755 * if we want to align the real payload, then we can 756 * just pretent we simply have two headers. */ 757 align = (long)wb->buf + 2*SSL3_RT_HEADER_LENGTH; 758 align = (-align)&(SSL3_ALIGN_PAYLOAD-1); 759#endif 760 p = wb->buf + align; 761 wb->offset = align; 762 } 763 else if (prefix_len) 764 { 765 p = wb->buf + wb->offset + prefix_len; 766 } 767 else 768 { 769#if defined(SSL3_ALIGN_PAYLOAD) && SSL3_ALIGN_PAYLOAD!=0 770 align = (long)wb->buf + SSL3_RT_HEADER_LENGTH; 771 align = (-align)&(SSL3_ALIGN_PAYLOAD-1); 772#endif 773 p = wb->buf + align; 774 wb->offset = align; 775 } 776 777 /* write the header */ 778 779 *(p++)=type&0xff; 780 wr->type=type; 781 782 *(p++)=(s->version>>8); 783 /* Some servers hang if iniatial client hello is larger than 256 784 * bytes and record version number > TLS 1.0 785 */ 786 if (s->state == SSL3_ST_CW_CLNT_HELLO_B 787 && !s->renegotiate 788 && TLS1_get_version(s) > TLS1_VERSION) 789 *(p++) = 0x1; 790 else 791 *(p++)=s->version&0xff; 792 793 /* field where we are to write out packet length */ 794 plen=p; 795 p+=2; 796 /* Explicit IV length, block ciphers and TLS version 1.1 or later */ 797 if (s->enc_write_ctx && s->version >= TLS1_1_VERSION) 798 { 799 int mode = EVP_CIPHER_CTX_mode(s->enc_write_ctx); 800 if (mode == EVP_CIPH_CBC_MODE) 801 { 802 eivlen = EVP_CIPHER_CTX_iv_length(s->enc_write_ctx); 803 if (eivlen <= 1) 804 eivlen = 0; 805 } 806 /* Need explicit part of IV for GCM mode */ 807 else if (mode == EVP_CIPH_GCM_MODE) 808 eivlen = EVP_GCM_TLS_EXPLICIT_IV_LEN; 809 else 810 eivlen = 0; 811 } 812 else 813 eivlen = 0; 814 815 /* lets setup the record stuff. */ 816 wr->data=p + eivlen; 817 wr->length=(int)len; 818 wr->input=(unsigned char *)buf; 819 820 /* we now 'read' from wr->input, wr->length bytes into 821 * wr->data */ 822 823 /* first we compress */ 824 if (s->compress != NULL) 825 { 826 if (!ssl3_do_compress(s)) 827 { 828 SSLerr(SSL_F_DO_SSL3_WRITE,SSL_R_COMPRESSION_FAILURE); 829 goto err; 830 } 831 } 832 else 833 { 834 memcpy(wr->data,wr->input,wr->length); 835 wr->input=wr->data; 836 } 837 838 /* we should still have the output to wr->data and the input 839 * from wr->input. Length should be wr->length. 840 * wr->data still points in the wb->buf */ 841 842 if (mac_size != 0) 843 { 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) 855 goto err; */ 856 wr->length += eivlen; 857 } 858 859 /* ssl3_enc can only have an error on read */ 860 s->method->ssl3_enc->enc(s,1); 861 862 /* record length after mac and block padding */ 863 s2n(wr->length,plen); 864 865 /* we should now have 866 * wr->data pointing to the encrypted data, which is 867 * wr->length long */ 868 wr->type=type; /* not needed but helps for debugging */ 869 wr->length+=SSL3_RT_HEADER_LENGTH; 870 871 if (create_empty_fragment) 872 { 873 /* we are in a recursive call; 874 * just return the length, don't write out anything here 875 */ 876 return wr->length; 877 } 878 879 /* now let's set up wb */ 880 wb->left = prefix_len + wr->length; 881 882 /* memorize arguments so that ssl3_write_pending can detect bad write retries later */ 883 s->s3->wpend_tot=len; 884 s->s3->wpend_buf=buf; 885 s->s3->wpend_type=type; 886 s->s3->wpend_ret=len; 887 888 /* we now just need to write the buffer */ 889 return ssl3_write_pending(s,type,buf,len); 890err: 891 return -1; 892 } 893 894/* if s->s3->wbuf.left != 0, we need to call this */ 895int ssl3_write_pending(SSL *s, int type, const unsigned char *buf, 896 unsigned int len) 897 { 898 int i; 899 SSL3_BUFFER *wb=&(s->s3->wbuf); 900 901/* XXXX */ 902 if ((s->s3->wpend_tot > (int)len) 903 || ((s->s3->wpend_buf != buf) && 904 !(s->mode & SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER)) 905 || (s->s3->wpend_type != type)) 906 { 907 SSLerr(SSL_F_SSL3_WRITE_PENDING,SSL_R_BAD_WRITE_RETRY); 908 return(-1); 909 } 910 911 for (;;) 912 { 913 clear_sys_error(); 914 if (s->wbio != NULL) 915 { 916 s->rwstate=SSL_WRITING; 917 i=BIO_write(s->wbio, 918 (char *)&(wb->buf[wb->offset]), 919 (unsigned int)wb->left); 920 } 921 else 922 { 923 SSLerr(SSL_F_SSL3_WRITE_PENDING,SSL_R_BIO_NOT_SET); 924 i= -1; 925 } 926 if (i == wb->left) 927 { 928 wb->left=0; 929 wb->offset+=i; 930 if (s->mode & SSL_MODE_RELEASE_BUFFERS && 931 SSL_version(s) != DTLS1_VERSION && SSL_version(s) != DTLS1_BAD_VER) 932 ssl3_release_write_buffer(s); 933 s->rwstate=SSL_NOTHING; 934 return(s->s3->wpend_ret); 935 } 936 else if (i <= 0) { 937 if (s->version == DTLS1_VERSION || 938 s->version == DTLS1_BAD_VER) { 939 /* For DTLS, just drop it. That's kind of the whole 940 point in using a datagram service */ 941 wb->left = 0; 942 } 943 return(i); 944 } 945 wb->offset+=i; 946 wb->left-=i; 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) && (type != SSL3_RT_HANDSHAKE)) || 989 (peek && (type != SSL3_RT_APPLICATION_DATA))) 990 { 991 SSLerr(SSL_F_SSL3_READ_BYTES, ERR_R_INTERNAL_ERROR); 992 return -1; 993 } 994 995 if ((type == SSL3_RT_HANDSHAKE) && (s->s3->handshake_fragment_len > 0)) 996 /* (partially) satisfy request from storage */ 997 { 998 unsigned char *src = s->s3->handshake_fragment; 999 unsigned char *dst = buf; 1000 unsigned int k; 1001 1002 /* peek == 0 */ 1003 n = 0; 1004 while ((len > 0) && (s->s3->handshake_fragment_len > 0)) 1005 { 1006 *dst++ = *src++; 1007 len--; s->s3->handshake_fragment_len--; 1008 n++; 1009 } 1010 /* move any remaining fragment bytes: */ 1011 for (k = 0; k < s->s3->handshake_fragment_len; k++) 1012 s->s3->handshake_fragment[k] = *src++; 1013 return n; 1014 } 1015 1016 /* Now s->s3->handshake_fragment_len == 0 if type == SSL3_RT_HANDSHAKE. */ 1017 1018 if (!s->in_handshake && SSL_in_init(s)) 1019 { 1020 /* type == SSL3_RT_APPLICATION_DATA */ 1021 i=s->handshake_func(s); 1022 if (i < 0) return(i); 1023 if (i == 0) 1024 { 1025 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE); 1026 return(-1); 1027 } 1028 } 1029start: 1030 s->rwstate=SSL_NOTHING; 1031 1032 /* s->s3->rrec.type - is the type of record 1033 * s->s3->rrec.data, - data 1034 * s->s3->rrec.off, - offset into 'data' for next read 1035 * s->s3->rrec.length, - number of bytes. */ 1036 rr = &(s->s3->rrec); 1037 1038 /* get new packet if necessary */ 1039 if ((rr->length == 0) || (s->rstate == SSL_ST_READ_BODY)) 1040 { 1041 ret=ssl3_get_record(s); 1042 if (ret <= 0) return(ret); 1043 } 1044 1045 /* we now have a packet which can be read and processed */ 1046 1047 if (s->s3->change_cipher_spec /* set when we receive ChangeCipherSpec, 1048 * reset by ssl3_get_finished */ 1049 && (rr->type != SSL3_RT_HANDSHAKE)) 1050 { 1051 al=SSL_AD_UNEXPECTED_MESSAGE; 1052 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_DATA_BETWEEN_CCS_AND_FINISHED); 1053 goto f_err; 1054 } 1055 1056 /* If the other end has shut down, throw anything we read away 1057 * (even in 'peek' mode) */ 1058 if (s->shutdown & SSL_RECEIVED_SHUTDOWN) 1059 { 1060 rr->length=0; 1061 s->rwstate=SSL_NOTHING; 1062 return(0); 1063 } 1064 1065 1066 if (type == rr->type) /* SSL3_RT_APPLICATION_DATA or SSL3_RT_HANDSHAKE */ 1067 { 1068 /* make sure that we are not getting application data when we 1069 * are doing a handshake for the first time */ 1070 if (SSL_in_init(s) && (type == SSL3_RT_APPLICATION_DATA) && 1071 (s->enc_read_ctx == NULL)) 1072 { 1073 al=SSL_AD_UNEXPECTED_MESSAGE; 1074 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_APP_DATA_IN_HANDSHAKE); 1075 goto f_err; 1076 } 1077 1078 if (len <= 0) return(len); 1079 1080 if ((unsigned int)len > rr->length) 1081 n = rr->length; 1082 else 1083 n = (unsigned int)len; 1084 1085 memcpy(buf,&(rr->data[rr->off]),n); 1086 if (!peek) 1087 { 1088 rr->length-=n; 1089 rr->off+=n; 1090 if (rr->length == 0) 1091 { 1092 s->rstate=SSL_ST_READ_HEADER; 1093 rr->off=0; 1094 if (s->mode & SSL_MODE_RELEASE_BUFFERS && s->s3->rbuf.left == 0) 1095 ssl3_release_read_buffer(s); 1096 } 1097 } 1098 return(n); 1099 } 1100 1101 1102 /* If we get here, then type != rr->type; if we have a handshake 1103 * message, then it was unexpected (Hello Request or Client Hello). */ 1104 1105 /* In case of record types for which we have 'fragment' storage, 1106 * fill that so that we can process the data at a fixed place. 1107 */ 1108 { 1109 unsigned int dest_maxlen = 0; 1110 unsigned char *dest = NULL; 1111 unsigned int *dest_len = NULL; 1112 1113 if (rr->type == SSL3_RT_HANDSHAKE) 1114 { 1115 dest_maxlen = sizeof s->s3->handshake_fragment; 1116 dest = s->s3->handshake_fragment; 1117 dest_len = &s->s3->handshake_fragment_len; 1118 } 1119 else if (rr->type == SSL3_RT_ALERT) 1120 { 1121 dest_maxlen = sizeof s->s3->alert_fragment; 1122 dest = s->s3->alert_fragment; 1123 dest_len = &s->s3->alert_fragment_len; 1124 } 1125#ifndef OPENSSL_NO_HEARTBEATS 1126 else if (rr->type == TLS1_RT_HEARTBEAT) 1127 { 1128 tls1_process_heartbeat(s); 1129 1130 /* Exit and notify application to read again */ 1131 rr->length = 0; 1132 s->rwstate=SSL_READING; 1133 BIO_clear_retry_flags(SSL_get_rbio(s)); 1134 BIO_set_retry_read(SSL_get_rbio(s)); 1135 return(-1); 1136 } 1137#endif 1138 1139 if (dest_maxlen > 0) 1140 { 1141 n = dest_maxlen - *dest_len; /* available space in 'dest' */ 1142 if (rr->length < n) 1143 n = rr->length; /* available bytes */ 1144 1145 /* now move 'n' bytes: */ 1146 while (n-- > 0) 1147 { 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 /* s->s3->handshake_fragment_len == 4 iff rr->type == SSL3_RT_HANDSHAKE; 1158 * s->s3->alert_fragment_len == 2 iff rr->type == SSL3_RT_ALERT. 1159 * (Possibly rr is 'empty' now, i.e. rr->length may be 0.) */ 1160 1161 /* If we are a client, check for an incoming 'Hello Request': */ 1162 if ((!s->server) && 1163 (s->s3->handshake_fragment_len >= 4) && 1164 (s->s3->handshake_fragment[0] == SSL3_MT_HELLO_REQUEST) && 1165 (s->session != NULL) && (s->session->cipher != NULL)) 1166 { 1167 s->s3->handshake_fragment_len = 0; 1168 1169 if ((s->s3->handshake_fragment[1] != 0) || 1170 (s->s3->handshake_fragment[2] != 0) || 1171 (s->s3->handshake_fragment[3] != 0)) 1172 { 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, s->s3->handshake_fragment, 4, s, s->msg_callback_arg); 1180 1181 if (SSL_is_init_finished(s) && 1182 !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS) && 1183 !s->s3->renegotiate) 1184 { 1185 ssl3_renegotiate(s); 1186 if (ssl3_renegotiate_check(s)) 1187 { 1188 i=s->handshake_func(s); 1189 if (i < 0) return(i); 1190 if (i == 0) 1191 { 1192 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE); 1193 return(-1); 1194 } 1195 1196 if (!(s->mode & SSL_MODE_AUTO_RETRY)) 1197 { 1198 if (s->s3->rbuf.left == 0) /* no read-ahead left? */ 1199 { 1200 BIO *bio; 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 s->rwstate=SSL_READING; 1206 bio=SSL_get_rbio(s); 1207 BIO_clear_retry_flags(bio); 1208 BIO_set_retry_read(bio); 1209 return(-1); 1210 } 1211 } 1212 } 1213 } 1214 /* we either finished a handshake or ignored the request, 1215 * now try again to obtain the (application) data we were asked for */ 1216 goto start; 1217 } 1218 /* If we are a server and get a client hello when renegotiation isn't 1219 * allowed send back a no renegotiation alert and carry on. 1220 * WARNING: experimental code, needs reviewing (steve) 1221 */ 1222 if (s->server && 1223 SSL_is_init_finished(s) && 1224 !s->s3->send_connection_binding && 1225 (s->version > SSL3_VERSION) && 1226 (s->s3->handshake_fragment_len >= 4) && 1227 (s->s3->handshake_fragment[0] == SSL3_MT_CLIENT_HELLO) && 1228 (s->session != NULL) && (s->session->cipher != NULL) && 1229 !(s->ctx->options & SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION)) 1230 1231 { 1232 /*s->s3->handshake_fragment_len = 0;*/ 1233 rr->length = 0; 1234 ssl3_send_alert(s,SSL3_AL_WARNING, SSL_AD_NO_RENEGOTIATION); 1235 goto start; 1236 } 1237 if (s->s3->alert_fragment_len >= 2) 1238 { 1239 int alert_level = s->s3->alert_fragment[0]; 1240 int alert_descr = s->s3->alert_fragment[1]; 1241 1242 s->s3->alert_fragment_len = 0; 1243 1244 if (s->msg_callback) 1245 s->msg_callback(0, s->version, SSL3_RT_ALERT, s->s3->alert_fragment, 2, s, s->msg_callback_arg); 1246 1247 if (s->info_callback != NULL) 1248 cb=s->info_callback; 1249 else if (s->ctx->info_callback != NULL) 1250 cb=s->ctx->info_callback; 1251 1252 if (cb != NULL) 1253 { 1254 j = (alert_level << 8) | alert_descr; 1255 cb(s, SSL_CB_READ_ALERT, j); 1256 } 1257 1258 if (alert_level == 1) /* warning */ 1259 { 1260 s->s3->warn_alert = alert_descr; 1261 if (alert_descr == SSL_AD_CLOSE_NOTIFY) 1262 { 1263 s->shutdown |= SSL_RECEIVED_SHUTDOWN; 1264 return(0); 1265 } 1266 /* This is a warning but we receive it if we requested 1267 * renegotiation and the peer denied it. Terminate with 1268 * a fatal alert because if application tried to 1269 * renegotiatie it presumably had a good reason and 1270 * expects it to succeed. 1271 * 1272 * In future we might have a renegotiation where we 1273 * don't care if the peer refused it where we carry on. 1274 */ 1275 else if (alert_descr == SSL_AD_NO_RENEGOTIATION) 1276 { 1277 al = SSL_AD_HANDSHAKE_FAILURE; 1278 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_NO_RENEGOTIATION); 1279 goto f_err; 1280 } 1281#ifdef SSL_AD_MISSING_SRP_USERNAME 1282 else if (alert_descr == SSL_AD_MISSING_SRP_USERNAME) 1283 return(0); 1284#endif 1285 } 1286 else if (alert_level == 2) /* fatal */ 1287 { 1288 char tmp[16]; 1289 1290 s->rwstate=SSL_NOTHING; 1291 s->s3->fatal_alert = alert_descr; 1292 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_AD_REASON_OFFSET + alert_descr); 1293 BIO_snprintf(tmp,sizeof tmp,"%d",alert_descr); 1294 ERR_add_error_data(2,"SSL alert number ",tmp); 1295 s->shutdown|=SSL_RECEIVED_SHUTDOWN; 1296 SSL_CTX_remove_session(s->ctx,s->session); 1297 return(0); 1298 } 1299 else 1300 { 1301 al=SSL_AD_ILLEGAL_PARAMETER; 1302 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNKNOWN_ALERT_TYPE); 1303 goto f_err; 1304 } 1305 1306 goto start; 1307 } 1308 1309 if (s->shutdown & SSL_SENT_SHUTDOWN) /* but we have not received a shutdown */ 1310 { 1311 s->rwstate=SSL_NOTHING; 1312 rr->length=0; 1313 return(0); 1314 } 1315 1316 if (rr->type == SSL3_RT_CHANGE_CIPHER_SPEC) 1317 { 1318 /* 'Change Cipher Spec' is just a single byte, so we know 1319 * exactly what the record payload has to look like */ 1320 if ( (rr->length != 1) || (rr->off != 0) || 1321 (rr->data[0] != SSL3_MT_CCS)) 1322 { 1323 al=SSL_AD_ILLEGAL_PARAMETER; 1324 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_BAD_CHANGE_CIPHER_SPEC); 1325 goto f_err; 1326 } 1327 1328 /* Check we have a cipher to change to */ 1329 if (s->s3->tmp.new_cipher == NULL) 1330 { 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 if (!(s->s3->flags & SSL3_FLAGS_CCS_OK)) 1337 { 1338 al=SSL_AD_UNEXPECTED_MESSAGE; 1339 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_CCS_RECEIVED_EARLY); 1340 goto f_err; 1341 } 1342 1343 s->s3->flags &= ~SSL3_FLAGS_CCS_OK; 1344 1345 rr->length=0; 1346 1347 if (s->msg_callback) 1348 s->msg_callback(0, s->version, SSL3_RT_CHANGE_CIPHER_SPEC, rr->data, 1, s, s->msg_callback_arg); 1349 1350 s->s3->change_cipher_spec=1; 1351 if (!ssl3_do_change_cipher_spec(s)) 1352 goto err; 1353 else 1354 goto start; 1355 } 1356 1357 /* Unexpected handshake message (Client Hello, or protocol violation) */ 1358 if ((s->s3->handshake_fragment_len >= 4) && !s->in_handshake) 1359 { 1360 if (((s->state&SSL_ST_MASK) == SSL_ST_OK) && 1361 !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS)) 1362 { 1363#if 0 /* worked only because C operator preferences are not as expected (and 1364 * because this is not really needed for clients except for detecting 1365 * protocol violations): */ 1366 s->state=SSL_ST_BEFORE|(s->server) 1367 ?SSL_ST_ACCEPT 1368 :SSL_ST_CONNECT; 1369#else 1370 s->state = s->server ? SSL_ST_ACCEPT : SSL_ST_CONNECT; 1371#endif 1372 s->renegotiate=1; 1373 s->new_session=1; 1374 } 1375 i=s->handshake_func(s); 1376 if (i < 0) return(i); 1377 if (i == 0) 1378 { 1379 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE); 1380 return(-1); 1381 } 1382 1383 if (!(s->mode & SSL_MODE_AUTO_RETRY)) 1384 { 1385 if (s->s3->rbuf.left == 0) /* no read-ahead left? */ 1386 { 1387 BIO *bio; 1388 /* In the case where we try to read application data, 1389 * but we trigger an SSL handshake, we return -1 with 1390 * the retry option set. Otherwise renegotiation may 1391 * cause nasty problems in the blocking world */ 1392 s->rwstate=SSL_READING; 1393 bio=SSL_get_rbio(s); 1394 BIO_clear_retry_flags(bio); 1395 BIO_set_retry_read(bio); 1396 return(-1); 1397 } 1398 } 1399 goto start; 1400 } 1401 1402 switch (rr->type) 1403 { 1404 default: 1405#ifndef OPENSSL_NO_TLS 1406 /* TLS up to v1.1 just ignores unknown message types: 1407 * TLS v1.2 give an unexpected message alert. 1408 */ 1409 if (s->version >= TLS1_VERSION && s->version <= TLS1_1_VERSION) 1410 { 1411 rr->length = 0; 1412 goto start; 1413 } 1414#endif 1415 al=SSL_AD_UNEXPECTED_MESSAGE; 1416 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNEXPECTED_RECORD); 1417 goto f_err; 1418 case SSL3_RT_CHANGE_CIPHER_SPEC: 1419 case SSL3_RT_ALERT: 1420 case SSL3_RT_HANDSHAKE: 1421 /* we already handled all of these, with the possible exception 1422 * of SSL3_RT_HANDSHAKE when s->in_handshake is set, but that 1423 * should not happen when type != rr->type */ 1424 al=SSL_AD_UNEXPECTED_MESSAGE; 1425 SSLerr(SSL_F_SSL3_READ_BYTES,ERR_R_INTERNAL_ERROR); 1426 goto f_err; 1427 case SSL3_RT_APPLICATION_DATA: 1428 /* At this point, we were expecting handshake data, 1429 * but have application data. If the library was 1430 * running inside ssl3_read() (i.e. in_read_app_data 1431 * is set) and it makes sense to read application data 1432 * at this point (session renegotiation not yet started), 1433 * we will indulge it. 1434 */ 1435 if (s->s3->in_read_app_data && 1436 (s->s3->total_renegotiations != 0) && 1437 (( 1438 (s->state & SSL_ST_CONNECT) && 1439 (s->state >= SSL3_ST_CW_CLNT_HELLO_A) && 1440 (s->state <= SSL3_ST_CR_SRVR_HELLO_A) 1441 ) || ( 1442 (s->state & SSL_ST_ACCEPT) && 1443 (s->state <= SSL3_ST_SW_HELLO_REQ_A) && 1444 (s->state >= SSL3_ST_SR_CLNT_HELLO_A) 1445 ) 1446 )) 1447 { 1448 s->s3->in_read_app_data=2; 1449 return(-1); 1450 } 1451 else 1452 { 1453 al=SSL_AD_UNEXPECTED_MESSAGE; 1454 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNEXPECTED_RECORD); 1455 goto f_err; 1456 } 1457 } 1458 /* not reached */ 1459 1460f_err: 1461 ssl3_send_alert(s,SSL3_AL_FATAL,al); 1462err: 1463 return(-1); 1464 } 1465 1466int ssl3_do_change_cipher_spec(SSL *s) 1467 { 1468 int i; 1469 const char *sender; 1470 int slen; 1471 1472 if (s->state & SSL_ST_ACCEPT) 1473 i=SSL3_CHANGE_CIPHER_SERVER_READ; 1474 else 1475 i=SSL3_CHANGE_CIPHER_CLIENT_READ; 1476 1477 if (s->s3->tmp.key_block == NULL) 1478 { 1479 if (s->session == NULL || s->session->master_key_length == 0) 1480 { 1481 /* might happen if dtls1_read_bytes() calls this */ 1482 SSLerr(SSL_F_SSL3_DO_CHANGE_CIPHER_SPEC,SSL_R_CCS_RECEIVED_EARLY); 1483 return (0); 1484 } 1485 1486 s->session->cipher=s->s3->tmp.new_cipher; 1487 if (!s->method->ssl3_enc->setup_key_block(s)) return(0); 1488 } 1489 1490 if (!s->method->ssl3_enc->change_cipher_state(s,i)) 1491 return(0); 1492 1493 /* we have to record the message digest at 1494 * this point so we can get it before we read 1495 * the finished message */ 1496 if (s->state & SSL_ST_CONNECT) 1497 { 1498 sender=s->method->ssl3_enc->server_finished_label; 1499 slen=s->method->ssl3_enc->server_finished_label_len; 1500 } 1501 else 1502 { 1503 sender=s->method->ssl3_enc->client_finished_label; 1504 slen=s->method->ssl3_enc->client_finished_label_len; 1505 } 1506 1507 i = s->method->ssl3_enc->final_finish_mac(s, 1508 sender,slen,s->s3->tmp.peer_finish_md); 1509 if (i == 0) 1510 { 1511 SSLerr(SSL_F_SSL3_DO_CHANGE_CIPHER_SPEC, ERR_R_INTERNAL_ERROR); 1512 return 0; 1513 } 1514 s->s3->tmp.peer_finish_md_len = i; 1515 1516 return(1); 1517 } 1518 1519int ssl3_send_alert(SSL *s, int level, int desc) 1520 { 1521 /* Map tls/ssl alert value to correct one */ 1522 desc=s->method->ssl3_enc->alert_value(desc); 1523 if (s->version == SSL3_VERSION && desc == SSL_AD_PROTOCOL_VERSION) 1524 desc = SSL_AD_HANDSHAKE_FAILURE; /* SSL 3.0 does not have protocol_version alerts */ 1525 if (desc < 0) return -1; 1526 /* If a fatal one, remove from cache */ 1527 if ((level == 2) && (s->session != NULL)) 1528 SSL_CTX_remove_session(s->ctx,s->session); 1529 1530 s->s3->alert_dispatch=1; 1531 s->s3->send_alert[0]=level; 1532 s->s3->send_alert[1]=desc; 1533 if (s->s3->wbuf.left == 0) /* data still being written out? */ 1534 return s->method->ssl_dispatch_alert(s); 1535 /* else data is still being written out, we will get written 1536 * some time in the future */ 1537 return -1; 1538 } 1539 1540int ssl3_dispatch_alert(SSL *s) 1541 { 1542 int i,j; 1543 void (*cb)(const SSL *ssl,int type,int val)=NULL; 1544 1545 s->s3->alert_dispatch=0; 1546 i = do_ssl3_write(s, SSL3_RT_ALERT, &s->s3->send_alert[0], 2, 0); 1547 if (i <= 0) 1548 { 1549 s->s3->alert_dispatch=1; 1550 } 1551 else 1552 { 1553 /* Alert sent to BIO. If it is important, flush it now. 1554 * If the message does not get sent due to non-blocking IO, 1555 * we will not worry too much. */ 1556 if (s->s3->send_alert[0] == SSL3_AL_FATAL) 1557 (void)BIO_flush(s->wbio); 1558 1559 if (s->msg_callback) 1560 s->msg_callback(1, s->version, SSL3_RT_ALERT, s->s3->send_alert, 2, s, s->msg_callback_arg); 1561 1562 if (s->info_callback != NULL) 1563 cb=s->info_callback; 1564 else if (s->ctx->info_callback != NULL) 1565 cb=s->ctx->info_callback; 1566 1567 if (cb != NULL) 1568 { 1569 j=(s->s3->send_alert[0]<<8)|s->s3->send_alert[1]; 1570 cb(s,SSL_CB_WRITE_ALERT,j); 1571 } 1572 } 1573 return(i); 1574 } 1575