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 120static int do_ssl3_write(SSL *s, int type, const unsigned char *buf, 121 unsigned int len, int create_empty_fragment); 122static int ssl3_get_record(SSL *s); 123 124int ssl3_read_n(SSL *s, int n, int max, int extend) 125 { 126 /* If extend == 0, obtain new n-byte packet; if extend == 1, increase 127 * packet by another n bytes. 128 * The packet will be in the sub-array of s->s3->rbuf.buf specified 129 * by s->packet and s->packet_length. 130 * (If s->read_ahead is set, 'max' bytes may be stored in rbuf 131 * [plus s->packet_length bytes if extend == 1].) 132 */ 133 int i,len,left; 134 long align=0; 135 unsigned char *pkt; 136 SSL3_BUFFER *rb; 137 138 if (n <= 0) return n; 139 140 rb = &(s->s3->rbuf); 141 if (rb->buf == NULL) 142 if (!ssl3_setup_read_buffer(s)) 143 return -1; 144 145 left = rb->left; 146#if defined(SSL3_ALIGN_PAYLOAD) && SSL3_ALIGN_PAYLOAD!=0 147 align = (long)rb->buf + SSL3_RT_HEADER_LENGTH; 148 align = (-align)&(SSL3_ALIGN_PAYLOAD-1); 149#endif 150 151 if (!extend) 152 { 153 /* start with empty packet ... */ 154 if (left == 0) 155 rb->offset = align; 156 else if (align != 0 && left >= SSL3_RT_HEADER_LENGTH) 157 { 158 /* check if next packet length is large 159 * enough to justify payload alignment... */ 160 pkt = rb->buf + rb->offset; 161 if (pkt[0] == SSL3_RT_APPLICATION_DATA 162 && (pkt[3]<<8|pkt[4]) >= 128) 163 { 164 /* Note that even if packet is corrupted 165 * and its length field is insane, we can 166 * only be led to wrong decision about 167 * whether memmove will occur or not. 168 * Header values has no effect on memmove 169 * arguments and therefore no buffer 170 * overrun can be triggered. */ 171 memmove (rb->buf+align,pkt,left); 172 rb->offset = align; 173 } 174 } 175 s->packet = rb->buf + rb->offset; 176 s->packet_length = 0; 177 /* ... now we can act as if 'extend' was set */ 178 } 179 180 /* For DTLS/UDP reads should not span multiple packets 181 * because the read operation returns the whole packet 182 * at once (as long as it fits into the buffer). */ 183 if (SSL_version(s) == DTLS1_VERSION || SSL_version(s) == DTLS1_BAD_VER) 184 { 185 if (left == 0 && extend) 186 return 0; 187 if (left > 0 && n > left) 188 n = left; 189 } 190 191 /* if there is enough in the buffer from a previous read, take some */ 192 if (left >= n) 193 { 194 s->packet_length+=n; 195 rb->left=left-n; 196 rb->offset+=n; 197 return(n); 198 } 199 200 /* else we need to read more data */ 201 202 len = s->packet_length; 203 pkt = rb->buf+align; 204 /* Move any available bytes to front of buffer: 205 * 'len' bytes already pointed to by 'packet', 206 * 'left' extra ones at the end */ 207 if (s->packet != pkt) /* len > 0 */ 208 { 209 memmove(pkt, s->packet, len+left); 210 s->packet = pkt; 211 rb->offset = len + align; 212 } 213 214 if (n > (int)(rb->len - rb->offset)) /* does not happen */ 215 { 216 SSLerr(SSL_F_SSL3_READ_N,ERR_R_INTERNAL_ERROR); 217 return -1; 218 } 219 220 if (!s->read_ahead) 221 /* ignore max parameter */ 222 max = n; 223 else 224 { 225 if (max < n) 226 max = n; 227 if (max > (int)(rb->len - rb->offset)) 228 max = rb->len - rb->offset; 229 } 230 231 while (left < n) 232 { 233 /* Now we have len+left bytes at the front of s->s3->rbuf.buf 234 * and need to read in more until we have len+n (up to 235 * len+max if possible) */ 236 237 clear_sys_error(); 238 if (s->rbio != NULL) 239 { 240 s->rwstate=SSL_READING; 241 i=BIO_read(s->rbio,pkt+len+left, max-left); 242 } 243 else 244 { 245 SSLerr(SSL_F_SSL3_READ_N,SSL_R_READ_BIO_NOT_SET); 246 i = -1; 247 } 248 249 if (i <= 0) 250 { 251 rb->left = left; 252 if (s->mode & SSL_MODE_RELEASE_BUFFERS && 253 SSL_version(s) != DTLS1_VERSION && SSL_version(s) != DTLS1_BAD_VER) 254 if (len+left == 0) 255 ssl3_release_read_buffer(s); 256 return(i); 257 } 258 left+=i; 259 /* reads should *never* span multiple packets for DTLS because 260 * the underlying transport protocol is message oriented as opposed 261 * to byte oriented as in the TLS case. */ 262 if (SSL_version(s) == DTLS1_VERSION || SSL_version(s) == DTLS1_BAD_VER) 263 { 264 if (n > left) 265 n = left; /* makes the while condition false */ 266 } 267 } 268 269 /* done reading, now the book-keeping */ 270 rb->offset += n; 271 rb->left = left - n; 272 s->packet_length += n; 273 s->rwstate=SSL_NOTHING; 274 return(n); 275 } 276 277/* MAX_EMPTY_RECORDS defines the number of consecutive, empty records that will 278 * be processed per call to ssl3_get_record. Without this limit an attacker 279 * could send empty records at a faster rate than we can process and cause 280 * ssl3_get_record to loop forever. */ 281#define MAX_EMPTY_RECORDS 32 282 283/* Call this to get a new input record. 284 * It will return <= 0 if more data is needed, normally due to an error 285 * or non-blocking IO. 286 * When it finishes, one packet has been decoded and can be found in 287 * ssl->s3->rrec.type - is the type of record 288 * ssl->s3->rrec.data, - data 289 * ssl->s3->rrec.length, - number of bytes 290 */ 291/* used only by ssl3_read_bytes */ 292static int ssl3_get_record(SSL *s) 293 { 294 int ssl_major,ssl_minor,al; 295 int enc_err,n,i,ret= -1; 296 SSL3_RECORD *rr; 297 SSL_SESSION *sess; 298 unsigned char *p; 299 unsigned char md[EVP_MAX_MD_SIZE]; 300 short version; 301 unsigned mac_size, orig_len; 302 size_t extra; 303 unsigned empty_record_count = 0; 304 305 rr= &(s->s3->rrec); 306 sess=s->session; 307 308 if (s->options & SSL_OP_MICROSOFT_BIG_SSLV3_BUFFER) 309 extra=SSL3_RT_MAX_EXTRA; 310 else 311 extra=0; 312 if (extra && !s->s3->init_extra) 313 { 314 /* An application error: SLS_OP_MICROSOFT_BIG_SSLV3_BUFFER 315 * set after ssl3_setup_buffers() was done */ 316 SSLerr(SSL_F_SSL3_GET_RECORD, ERR_R_INTERNAL_ERROR); 317 return -1; 318 } 319 320again: 321 /* check if we have the header */ 322 if ( (s->rstate != SSL_ST_READ_BODY) || 323 (s->packet_length < SSL3_RT_HEADER_LENGTH)) 324 { 325 n=ssl3_read_n(s, SSL3_RT_HEADER_LENGTH, s->s3->rbuf.len, 0); 326 if (n <= 0) return(n); /* error or non-blocking */ 327 s->rstate=SSL_ST_READ_BODY; 328 329 p=s->packet; 330 331 /* Pull apart the header into the SSL3_RECORD */ 332 rr->type= *(p++); 333 ssl_major= *(p++); 334 ssl_minor= *(p++); 335 version=(ssl_major<<8)|ssl_minor; 336 n2s(p,rr->length); 337#if 0 338fprintf(stderr, "Record type=%d, Length=%d\n", rr->type, rr->length); 339#endif 340 341 /* Lets check version */ 342 if (!s->first_packet) 343 { 344 if (version != s->version) 345 { 346 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_WRONG_VERSION_NUMBER); 347 if ((s->version & 0xFF00) == (version & 0xFF00)) 348 /* Send back error using their minor version number :-) */ 349 s->version = (unsigned short)version; 350 al=SSL_AD_PROTOCOL_VERSION; 351 goto f_err; 352 } 353 } 354 355 if ((version>>8) != SSL3_VERSION_MAJOR) 356 { 357 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_WRONG_VERSION_NUMBER); 358 goto err; 359 } 360 361 if (rr->length > s->s3->rbuf.len - SSL3_RT_HEADER_LENGTH) 362 { 363 al=SSL_AD_RECORD_OVERFLOW; 364 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_PACKET_LENGTH_TOO_LONG); 365 goto f_err; 366 } 367 368 /* now s->rstate == SSL_ST_READ_BODY */ 369 } 370 371 /* s->rstate == SSL_ST_READ_BODY, get and decode the data */ 372 373 if (rr->length > s->packet_length-SSL3_RT_HEADER_LENGTH) 374 { 375 /* now s->packet_length == SSL3_RT_HEADER_LENGTH */ 376 i=rr->length; 377 n=ssl3_read_n(s,i,i,1); 378 if (n <= 0) return(n); /* error or non-blocking io */ 379 /* now n == rr->length, 380 * and s->packet_length == SSL3_RT_HEADER_LENGTH + rr->length */ 381 } 382 383 s->rstate=SSL_ST_READ_HEADER; /* set state for later operations */ 384 385 /* At this point, s->packet_length == SSL3_RT_HEADER_LNGTH + rr->length, 386 * and we have that many bytes in s->packet 387 */ 388 rr->input= &(s->packet[SSL3_RT_HEADER_LENGTH]); 389 390 /* ok, we can now read from 's->packet' data into 'rr' 391 * rr->input points at rr->length bytes, which 392 * need to be copied into rr->data by either 393 * the decryption or by the decompression 394 * When the data is 'copied' into the rr->data buffer, 395 * rr->input will be pointed at the new buffer */ 396 397 /* We now have - encrypted [ MAC [ compressed [ plain ] ] ] 398 * rr->length bytes of encrypted compressed stuff. */ 399 400 /* check is not needed I believe */ 401 if (rr->length > SSL3_RT_MAX_ENCRYPTED_LENGTH+extra) 402 { 403 al=SSL_AD_RECORD_OVERFLOW; 404 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_ENCRYPTED_LENGTH_TOO_LONG); 405 goto f_err; 406 } 407 408 /* decrypt in place in 'rr->input' */ 409 rr->data=rr->input; 410 411 enc_err = s->method->ssl3_enc->enc(s,0); 412 /* enc_err is: 413 * 0: (in non-constant time) if the record is publically invalid. 414 * 1: if the padding is valid 415 * -1: if the padding is invalid */ 416 if (enc_err == 0) 417 { 418 al=SSL_AD_DECRYPTION_FAILED; 419 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_BLOCK_CIPHER_PAD_IS_WRONG); 420 goto f_err; 421 } 422 423#ifdef TLS_DEBUG 424printf("dec %d\n",rr->length); 425{ unsigned int z; for (z=0; z<rr->length; z++) printf("%02X%c",rr->data[z],((z+1)%16)?' ':'\n'); } 426printf("\n"); 427#endif 428 429 /* r->length is now the compressed data plus mac */ 430 if ((sess != NULL) && 431 (s->enc_read_ctx != NULL) && 432 (EVP_MD_CTX_md(s->read_hash) != NULL)) 433 { 434 /* s->read_hash != NULL => mac_size != -1 */ 435 unsigned char *mac = NULL; 436 unsigned char mac_tmp[EVP_MAX_MD_SIZE]; 437 mac_size=EVP_MD_CTX_size(s->read_hash); 438 OPENSSL_assert(mac_size <= EVP_MAX_MD_SIZE); 439 440 /* kludge: *_cbc_remove_padding passes padding length in rr->type */ 441 orig_len = rr->length+((unsigned int)rr->type>>8); 442 443 /* orig_len is the length of the record before any padding was 444 * removed. This is public information, as is the MAC in use, 445 * therefore we can safely process the record in a different 446 * amount of time if it's too short to possibly contain a MAC. 447 */ 448 if (orig_len < mac_size || 449 /* CBC records must have a padding length byte too. */ 450 (EVP_CIPHER_CTX_mode(s->enc_read_ctx) == EVP_CIPH_CBC_MODE && 451 orig_len < mac_size+1)) 452 { 453 al=SSL_AD_DECODE_ERROR; 454 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_LENGTH_TOO_SHORT); 455 goto f_err; 456 } 457 458 if (EVP_CIPHER_CTX_mode(s->enc_read_ctx) == EVP_CIPH_CBC_MODE) 459 { 460 /* We update the length so that the TLS header bytes 461 * can be constructed correctly but we need to extract 462 * the MAC in constant time from within the record, 463 * without leaking the contents of the padding bytes. 464 * */ 465 mac = mac_tmp; 466 ssl3_cbc_copy_mac(mac_tmp, rr, mac_size, orig_len); 467 rr->length -= mac_size; 468 } 469 else 470 { 471 /* In this case there's no padding, so |orig_len| 472 * equals |rec->length| and we checked that there's 473 * enough bytes for |mac_size| above. */ 474 rr->length -= mac_size; 475 mac = &rr->data[rr->length]; 476 } 477 478 i=s->method->ssl3_enc->mac(s,md,0 /* not send */); 479 if (i < 0 || mac == NULL || CRYPTO_memcmp(md, mac, (size_t)mac_size) != 0) 480 enc_err = -1; 481 if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH+extra+mac_size) 482 enc_err = -1; 483 } 484 485 if (enc_err < 0) 486 { 487 /* A separate 'decryption_failed' alert was introduced with TLS 1.0, 488 * SSL 3.0 only has 'bad_record_mac'. But unless a decryption 489 * failure is directly visible from the ciphertext anyway, 490 * we should not reveal which kind of error occured -- this 491 * might become visible to an attacker (e.g. via a logfile) */ 492 al=SSL_AD_BAD_RECORD_MAC; 493 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_DECRYPTION_FAILED_OR_BAD_RECORD_MAC); 494 goto f_err; 495 } 496 497 /* r->length is now just compressed */ 498 if (s->expand != NULL) 499 { 500 if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH+extra) 501 { 502 al=SSL_AD_RECORD_OVERFLOW; 503 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_COMPRESSED_LENGTH_TOO_LONG); 504 goto f_err; 505 } 506 if (!ssl3_do_uncompress(s)) 507 { 508 al=SSL_AD_DECOMPRESSION_FAILURE; 509 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_BAD_DECOMPRESSION); 510 goto f_err; 511 } 512 } 513 514 if (rr->length > SSL3_RT_MAX_PLAIN_LENGTH+extra) 515 { 516 al=SSL_AD_RECORD_OVERFLOW; 517 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_DATA_LENGTH_TOO_LONG); 518 goto f_err; 519 } 520 521 rr->off=0; 522 /* So at this point the following is true 523 * ssl->s3->rrec.type is the type of record 524 * ssl->s3->rrec.length == number of bytes in record 525 * ssl->s3->rrec.off == offset to first valid byte 526 * ssl->s3->rrec.data == where to take bytes from, increment 527 * after use :-). 528 */ 529 530 /* we have pulled in a full packet so zero things */ 531 s->packet_length=0; 532 533 /* just read a 0 length packet */ 534 if (rr->length == 0) 535 { 536 empty_record_count++; 537 if (empty_record_count > MAX_EMPTY_RECORDS) 538 { 539 al=SSL_AD_UNEXPECTED_MESSAGE; 540 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_RECORD_TOO_SMALL); 541 goto f_err; 542 } 543 goto again; 544 } 545 546#if 0 547fprintf(stderr, "Ultimate Record type=%d, Length=%d\n", rr->type, rr->length); 548#endif 549 550 return(1); 551 552f_err: 553 ssl3_send_alert(s,SSL3_AL_FATAL,al); 554err: 555 return(ret); 556 } 557 558int ssl3_do_uncompress(SSL *ssl) 559 { 560#ifndef OPENSSL_NO_COMP 561 int i; 562 SSL3_RECORD *rr; 563 564 rr= &(ssl->s3->rrec); 565 i=COMP_expand_block(ssl->expand,rr->comp, 566 SSL3_RT_MAX_PLAIN_LENGTH,rr->data,(int)rr->length); 567 if (i < 0) 568 return(0); 569 else 570 rr->length=i; 571 rr->data=rr->comp; 572#endif 573 return(1); 574 } 575 576int ssl3_do_compress(SSL *ssl) 577 { 578#ifndef OPENSSL_NO_COMP 579 int i; 580 SSL3_RECORD *wr; 581 582 wr= &(ssl->s3->wrec); 583 i=COMP_compress_block(ssl->compress,wr->data, 584 SSL3_RT_MAX_COMPRESSED_LENGTH, 585 wr->input,(int)wr->length); 586 if (i < 0) 587 return(0); 588 else 589 wr->length=i; 590 591 wr->input=wr->data; 592#endif 593 return(1); 594 } 595 596/* Call this to write data in records of type 'type' 597 * It will return <= 0 if not all data has been sent or non-blocking IO. 598 */ 599int ssl3_write_bytes(SSL *s, int type, const void *buf_, int len) 600 { 601 const unsigned char *buf=buf_; 602 unsigned int n,nw; 603 int i,tot; 604 605 s->rwstate=SSL_NOTHING; 606 OPENSSL_assert(s->s3->wnum <= INT_MAX); 607 tot=s->s3->wnum; 608 s->s3->wnum=0; 609 610 if (SSL_in_init(s) && !s->in_handshake) 611 { 612 i=s->handshake_func(s); 613 if (i < 0) return(i); 614 if (i == 0) 615 { 616 SSLerr(SSL_F_SSL3_WRITE_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE); 617 return -1; 618 } 619 } 620 621 /* ensure that if we end up with a smaller value of data to write 622 * out than the the original len from a write which didn't complete 623 * for non-blocking I/O and also somehow ended up avoiding 624 * the check for this in ssl3_write_pending/SSL_R_BAD_WRITE_RETRY as 625 * it must never be possible to end up with (len-tot) as a large 626 * number that will then promptly send beyond the end of the users 627 * buffer ... so we trap and report the error in a way the user 628 * will notice 629 */ 630 if (len < tot) 631 { 632 SSLerr(SSL_F_SSL3_WRITE_BYTES,SSL_R_BAD_LENGTH); 633 return(-1); 634 } 635 636 637 n=(len-tot); 638 for (;;) 639 { 640 if (n > s->max_send_fragment) 641 nw=s->max_send_fragment; 642 else 643 nw=n; 644 645 i=do_ssl3_write(s, type, &(buf[tot]), nw, 0); 646 if (i <= 0) 647 { 648 s->s3->wnum=tot; 649 return i; 650 } 651 652 if ((i == (int)n) || 653 (type == SSL3_RT_APPLICATION_DATA && 654 (s->mode & SSL_MODE_ENABLE_PARTIAL_WRITE))) 655 { 656 /* next chunk of data should get another prepended empty fragment 657 * in ciphersuites with known-IV weakness: */ 658 s->s3->empty_fragment_done = 0; 659 660 return tot+i; 661 } 662 663 n-=i; 664 tot+=i; 665 } 666 } 667 668static int do_ssl3_write(SSL *s, int type, const unsigned char *buf, 669 unsigned int len, int create_empty_fragment) 670 { 671 unsigned char *p,*plen; 672 int i,mac_size,clear=0; 673 int prefix_len=0; 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 clear=1; 708 709 if (clear) 710 mac_size=0; 711 else 712 { 713 mac_size=EVP_MD_CTX_size(s->write_hash); 714 if (mac_size < 0) 715 goto err; 716 } 717 718 /* 'create_empty_fragment' is true only when this function calls itself */ 719 if (!clear && !create_empty_fragment && !s->s3->empty_fragment_done) 720 { 721 /* countermeasure against known-IV weakness in CBC ciphersuites 722 * (see http://www.openssl.org/~bodo/tls-cbc.txt) */ 723 724 if (s->s3->need_empty_fragments && type == SSL3_RT_APPLICATION_DATA) 725 { 726 /* recursive function call with 'create_empty_fragment' set; 727 * this prepares and buffers the data for an empty fragment 728 * (these 'prefix_len' bytes are sent out later 729 * together with the actual payload) */ 730 prefix_len = do_ssl3_write(s, type, buf, 0, 1); 731 if (prefix_len <= 0) 732 goto err; 733 734 if (prefix_len > 735 (SSL3_RT_HEADER_LENGTH + SSL3_RT_SEND_MAX_ENCRYPTED_OVERHEAD)) 736 { 737 /* insufficient space */ 738 SSLerr(SSL_F_DO_SSL3_WRITE, ERR_R_INTERNAL_ERROR); 739 goto err; 740 } 741 } 742 743 s->s3->empty_fragment_done = 1; 744 } 745 746 if (create_empty_fragment) 747 { 748#if defined(SSL3_ALIGN_PAYLOAD) && SSL3_ALIGN_PAYLOAD!=0 749 /* extra fragment would be couple of cipher blocks, 750 * which would be multiple of SSL3_ALIGN_PAYLOAD, so 751 * if we want to align the real payload, then we can 752 * just pretent we simply have two headers. */ 753 align = (long)wb->buf + 2*SSL3_RT_HEADER_LENGTH; 754 align = (-align)&(SSL3_ALIGN_PAYLOAD-1); 755#endif 756 p = wb->buf + align; 757 wb->offset = align; 758 } 759 else if (prefix_len) 760 { 761 p = wb->buf + wb->offset + prefix_len; 762 } 763 else 764 { 765#if defined(SSL3_ALIGN_PAYLOAD) && SSL3_ALIGN_PAYLOAD!=0 766 align = (long)wb->buf + SSL3_RT_HEADER_LENGTH; 767 align = (-align)&(SSL3_ALIGN_PAYLOAD-1); 768#endif 769 p = wb->buf + align; 770 wb->offset = align; 771 } 772 773 /* write the header */ 774 775 *(p++)=type&0xff; 776 wr->type=type; 777 778 *(p++)=(s->version>>8); 779 *(p++)=s->version&0xff; 780 781 /* field where we are to write out packet length */ 782 plen=p; 783 p+=2; 784 785 /* lets setup the record stuff. */ 786 wr->data=p; 787 wr->length=(int)len; 788 wr->input=(unsigned char *)buf; 789 790 /* we now 'read' from wr->input, wr->length bytes into 791 * wr->data */ 792 793 /* first we compress */ 794 if (s->compress != NULL) 795 { 796 if (!ssl3_do_compress(s)) 797 { 798 SSLerr(SSL_F_DO_SSL3_WRITE,SSL_R_COMPRESSION_FAILURE); 799 goto err; 800 } 801 } 802 else 803 { 804 memcpy(wr->data,wr->input,wr->length); 805 wr->input=wr->data; 806 } 807 808 /* we should still have the output to wr->data and the input 809 * from wr->input. Length should be wr->length. 810 * wr->data still points in the wb->buf */ 811 812 if (mac_size != 0) 813 { 814 if (s->method->ssl3_enc->mac(s,&(p[wr->length]),1) < 0) 815 goto err; 816 wr->length+=mac_size; 817 wr->input=p; 818 wr->data=p; 819 } 820 821 if(s->method->ssl3_enc->enc(s,1)<1) goto err; 822 823 /* record length after mac and block padding */ 824 s2n(wr->length,plen); 825 826 /* we should now have 827 * wr->data pointing to the encrypted data, which is 828 * wr->length long */ 829 wr->type=type; /* not needed but helps for debugging */ 830 wr->length+=SSL3_RT_HEADER_LENGTH; 831 832 if (create_empty_fragment) 833 { 834 /* we are in a recursive call; 835 * just return the length, don't write out anything here 836 */ 837 return wr->length; 838 } 839 840 /* now let's set up wb */ 841 wb->left = prefix_len + wr->length; 842 843 /* memorize arguments so that ssl3_write_pending can detect bad write retries later */ 844 s->s3->wpend_tot=len; 845 s->s3->wpend_buf=buf; 846 s->s3->wpend_type=type; 847 s->s3->wpend_ret=len; 848 849 /* we now just need to write the buffer */ 850 return ssl3_write_pending(s,type,buf,len); 851err: 852 return -1; 853 } 854 855/* if s->s3->wbuf.left != 0, we need to call this */ 856int ssl3_write_pending(SSL *s, int type, const unsigned char *buf, 857 unsigned int len) 858 { 859 int i; 860 SSL3_BUFFER *wb=&(s->s3->wbuf); 861 862/* XXXX */ 863 if ((s->s3->wpend_tot > (int)len) 864 || ((s->s3->wpend_buf != buf) && 865 !(s->mode & SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER)) 866 || (s->s3->wpend_type != type)) 867 { 868 SSLerr(SSL_F_SSL3_WRITE_PENDING,SSL_R_BAD_WRITE_RETRY); 869 return(-1); 870 } 871 872 for (;;) 873 { 874 clear_sys_error(); 875 if (s->wbio != NULL) 876 { 877 s->rwstate=SSL_WRITING; 878 i=BIO_write(s->wbio, 879 (char *)&(wb->buf[wb->offset]), 880 (unsigned int)wb->left); 881 } 882 else 883 { 884 SSLerr(SSL_F_SSL3_WRITE_PENDING,SSL_R_BIO_NOT_SET); 885 i= -1; 886 } 887 if (i == wb->left) 888 { 889 wb->left=0; 890 wb->offset+=i; 891 if (s->mode & SSL_MODE_RELEASE_BUFFERS && 892 SSL_version(s) != DTLS1_VERSION && SSL_version(s) != DTLS1_BAD_VER) 893 ssl3_release_write_buffer(s); 894 s->rwstate=SSL_NOTHING; 895 return(s->s3->wpend_ret); 896 } 897 else if (i <= 0) { 898 if (s->version == DTLS1_VERSION || 899 s->version == DTLS1_BAD_VER) { 900 /* For DTLS, just drop it. That's kind of the whole 901 point in using a datagram service */ 902 wb->left = 0; 903 } 904 return(i); 905 } 906 wb->offset+=i; 907 wb->left-=i; 908 } 909 } 910 911/* Return up to 'len' payload bytes received in 'type' records. 912 * 'type' is one of the following: 913 * 914 * - SSL3_RT_HANDSHAKE (when ssl3_get_message calls us) 915 * - SSL3_RT_APPLICATION_DATA (when ssl3_read calls us) 916 * - 0 (during a shutdown, no data has to be returned) 917 * 918 * If we don't have stored data to work from, read a SSL/TLS record first 919 * (possibly multiple records if we still don't have anything to return). 920 * 921 * This function must handle any surprises the peer may have for us, such as 922 * Alert records (e.g. close_notify), ChangeCipherSpec records (not really 923 * a surprise, but handled as if it were), or renegotiation requests. 924 * Also if record payloads contain fragments too small to process, we store 925 * them until there is enough for the respective protocol (the record protocol 926 * may use arbitrary fragmentation and even interleaving): 927 * Change cipher spec protocol 928 * just 1 byte needed, no need for keeping anything stored 929 * Alert protocol 930 * 2 bytes needed (AlertLevel, AlertDescription) 931 * Handshake protocol 932 * 4 bytes needed (HandshakeType, uint24 length) -- we just have 933 * to detect unexpected Client Hello and Hello Request messages 934 * here, anything else is handled by higher layers 935 * Application data protocol 936 * none of our business 937 */ 938int ssl3_read_bytes(SSL *s, int type, unsigned char *buf, int len, int peek) 939 { 940 int al,i,j,ret; 941 unsigned int n; 942 SSL3_RECORD *rr; 943 void (*cb)(const SSL *ssl,int type2,int val)=NULL; 944 945 if (s->s3->rbuf.buf == NULL) /* Not initialized yet */ 946 if (!ssl3_setup_read_buffer(s)) 947 return(-1); 948 949 if ((type && (type != SSL3_RT_APPLICATION_DATA) && (type != SSL3_RT_HANDSHAKE)) || 950 (peek && (type != SSL3_RT_APPLICATION_DATA))) 951 { 952 SSLerr(SSL_F_SSL3_READ_BYTES, ERR_R_INTERNAL_ERROR); 953 return -1; 954 } 955 956 if ((type == SSL3_RT_HANDSHAKE) && (s->s3->handshake_fragment_len > 0)) 957 /* (partially) satisfy request from storage */ 958 { 959 unsigned char *src = s->s3->handshake_fragment; 960 unsigned char *dst = buf; 961 unsigned int k; 962 963 /* peek == 0 */ 964 n = 0; 965 while ((len > 0) && (s->s3->handshake_fragment_len > 0)) 966 { 967 *dst++ = *src++; 968 len--; s->s3->handshake_fragment_len--; 969 n++; 970 } 971 /* move any remaining fragment bytes: */ 972 for (k = 0; k < s->s3->handshake_fragment_len; k++) 973 s->s3->handshake_fragment[k] = *src++; 974 return n; 975 } 976 977 /* Now s->s3->handshake_fragment_len == 0 if type == SSL3_RT_HANDSHAKE. */ 978 979 if (!s->in_handshake && SSL_in_init(s)) 980 { 981 /* type == SSL3_RT_APPLICATION_DATA */ 982 i=s->handshake_func(s); 983 if (i < 0) return(i); 984 if (i == 0) 985 { 986 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE); 987 return(-1); 988 } 989 } 990start: 991 s->rwstate=SSL_NOTHING; 992 993 /* s->s3->rrec.type - is the type of record 994 * s->s3->rrec.data, - data 995 * s->s3->rrec.off, - offset into 'data' for next read 996 * s->s3->rrec.length, - number of bytes. */ 997 rr = &(s->s3->rrec); 998 999 /* get new packet if necessary */ 1000 if ((rr->length == 0) || (s->rstate == SSL_ST_READ_BODY)) 1001 { 1002 ret=ssl3_get_record(s); 1003 if (ret <= 0) return(ret); 1004 } 1005 1006 /* we now have a packet which can be read and processed */ 1007 1008 if (s->s3->change_cipher_spec /* set when we receive ChangeCipherSpec, 1009 * reset by ssl3_get_finished */ 1010 && (rr->type != SSL3_RT_HANDSHAKE)) 1011 { 1012 al=SSL_AD_UNEXPECTED_MESSAGE; 1013 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_DATA_BETWEEN_CCS_AND_FINISHED); 1014 goto f_err; 1015 } 1016 1017 /* If the other end has shut down, throw anything we read away 1018 * (even in 'peek' mode) */ 1019 if (s->shutdown & SSL_RECEIVED_SHUTDOWN) 1020 { 1021 rr->length=0; 1022 s->rwstate=SSL_NOTHING; 1023 return(0); 1024 } 1025 1026 1027 if (type == rr->type) /* SSL3_RT_APPLICATION_DATA or SSL3_RT_HANDSHAKE */ 1028 { 1029 /* make sure that we are not getting application data when we 1030 * are doing a handshake for the first time */ 1031 if (SSL_in_init(s) && (type == SSL3_RT_APPLICATION_DATA) && 1032 (s->enc_read_ctx == NULL)) 1033 { 1034 al=SSL_AD_UNEXPECTED_MESSAGE; 1035 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_APP_DATA_IN_HANDSHAKE); 1036 goto f_err; 1037 } 1038 1039 if (len <= 0) return(len); 1040 1041 if ((unsigned int)len > rr->length) 1042 n = rr->length; 1043 else 1044 n = (unsigned int)len; 1045 1046 memcpy(buf,&(rr->data[rr->off]),n); 1047 if (!peek) 1048 { 1049 rr->length-=n; 1050 rr->off+=n; 1051 if (rr->length == 0) 1052 { 1053 s->rstate=SSL_ST_READ_HEADER; 1054 rr->off=0; 1055 if (s->mode & SSL_MODE_RELEASE_BUFFERS && s->s3->rbuf.left == 0) 1056 ssl3_release_read_buffer(s); 1057 } 1058 } 1059 return(n); 1060 } 1061 1062 1063 /* If we get here, then type != rr->type; if we have a handshake 1064 * message, then it was unexpected (Hello Request or Client Hello). */ 1065 1066 /* In case of record types for which we have 'fragment' storage, 1067 * fill that so that we can process the data at a fixed place. 1068 */ 1069 { 1070 unsigned int dest_maxlen = 0; 1071 unsigned char *dest = NULL; 1072 unsigned int *dest_len = NULL; 1073 1074 if (rr->type == SSL3_RT_HANDSHAKE) 1075 { 1076 dest_maxlen = sizeof s->s3->handshake_fragment; 1077 dest = s->s3->handshake_fragment; 1078 dest_len = &s->s3->handshake_fragment_len; 1079 } 1080 else if (rr->type == SSL3_RT_ALERT) 1081 { 1082 dest_maxlen = sizeof s->s3->alert_fragment; 1083 dest = s->s3->alert_fragment; 1084 dest_len = &s->s3->alert_fragment_len; 1085 } 1086 1087 if (dest_maxlen > 0) 1088 { 1089 n = dest_maxlen - *dest_len; /* available space in 'dest' */ 1090 if (rr->length < n) 1091 n = rr->length; /* available bytes */ 1092 1093 /* now move 'n' bytes: */ 1094 while (n-- > 0) 1095 { 1096 dest[(*dest_len)++] = rr->data[rr->off++]; 1097 rr->length--; 1098 } 1099 1100 if (*dest_len < dest_maxlen) 1101 goto start; /* fragment was too small */ 1102 } 1103 } 1104 1105 /* s->s3->handshake_fragment_len == 4 iff rr->type == SSL3_RT_HANDSHAKE; 1106 * s->s3->alert_fragment_len == 2 iff rr->type == SSL3_RT_ALERT. 1107 * (Possibly rr is 'empty' now, i.e. rr->length may be 0.) */ 1108 1109 /* If we are a client, check for an incoming 'Hello Request': */ 1110 if ((!s->server) && 1111 (s->s3->handshake_fragment_len >= 4) && 1112 (s->s3->handshake_fragment[0] == SSL3_MT_HELLO_REQUEST) && 1113 (s->session != NULL) && (s->session->cipher != NULL)) 1114 { 1115 s->s3->handshake_fragment_len = 0; 1116 1117 if ((s->s3->handshake_fragment[1] != 0) || 1118 (s->s3->handshake_fragment[2] != 0) || 1119 (s->s3->handshake_fragment[3] != 0)) 1120 { 1121 al=SSL_AD_DECODE_ERROR; 1122 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_BAD_HELLO_REQUEST); 1123 goto f_err; 1124 } 1125 1126 if (s->msg_callback) 1127 s->msg_callback(0, s->version, SSL3_RT_HANDSHAKE, s->s3->handshake_fragment, 4, s, s->msg_callback_arg); 1128 1129 if (SSL_is_init_finished(s) && 1130 !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS) && 1131 !s->s3->renegotiate) 1132 { 1133 ssl3_renegotiate(s); 1134 if (ssl3_renegotiate_check(s)) 1135 { 1136 i=s->handshake_func(s); 1137 if (i < 0) return(i); 1138 if (i == 0) 1139 { 1140 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE); 1141 return(-1); 1142 } 1143 1144 if (!(s->mode & SSL_MODE_AUTO_RETRY)) 1145 { 1146 if (s->s3->rbuf.left == 0) /* no read-ahead left? */ 1147 { 1148 BIO *bio; 1149 /* In the case where we try to read application data, 1150 * but we trigger an SSL handshake, we return -1 with 1151 * the retry option set. Otherwise renegotiation may 1152 * cause nasty problems in the blocking world */ 1153 s->rwstate=SSL_READING; 1154 bio=SSL_get_rbio(s); 1155 BIO_clear_retry_flags(bio); 1156 BIO_set_retry_read(bio); 1157 return(-1); 1158 } 1159 } 1160 } 1161 } 1162 /* we either finished a handshake or ignored the request, 1163 * now try again to obtain the (application) data we were asked for */ 1164 goto start; 1165 } 1166 /* If we are a server and get a client hello when renegotiation isn't 1167 * allowed send back a no renegotiation alert and carry on. 1168 * WARNING: experimental code, needs reviewing (steve) 1169 */ 1170 if (s->server && 1171 SSL_is_init_finished(s) && 1172 !s->s3->send_connection_binding && 1173 (s->version > SSL3_VERSION) && 1174 (s->s3->handshake_fragment_len >= 4) && 1175 (s->s3->handshake_fragment[0] == SSL3_MT_CLIENT_HELLO) && 1176 (s->session != NULL) && (s->session->cipher != NULL) && 1177 !(s->ctx->options & SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION)) 1178 1179 { 1180 /*s->s3->handshake_fragment_len = 0;*/ 1181 rr->length = 0; 1182 ssl3_send_alert(s,SSL3_AL_WARNING, SSL_AD_NO_RENEGOTIATION); 1183 goto start; 1184 } 1185 if (s->s3->alert_fragment_len >= 2) 1186 { 1187 int alert_level = s->s3->alert_fragment[0]; 1188 int alert_descr = s->s3->alert_fragment[1]; 1189 1190 s->s3->alert_fragment_len = 0; 1191 1192 if (s->msg_callback) 1193 s->msg_callback(0, s->version, SSL3_RT_ALERT, s->s3->alert_fragment, 2, s, s->msg_callback_arg); 1194 1195 if (s->info_callback != NULL) 1196 cb=s->info_callback; 1197 else if (s->ctx->info_callback != NULL) 1198 cb=s->ctx->info_callback; 1199 1200 if (cb != NULL) 1201 { 1202 j = (alert_level << 8) | alert_descr; 1203 cb(s, SSL_CB_READ_ALERT, j); 1204 } 1205 1206 if (alert_level == 1) /* warning */ 1207 { 1208 s->s3->warn_alert = alert_descr; 1209 if (alert_descr == SSL_AD_CLOSE_NOTIFY) 1210 { 1211 s->shutdown |= SSL_RECEIVED_SHUTDOWN; 1212 return(0); 1213 } 1214 /* This is a warning but we receive it if we requested 1215 * renegotiation and the peer denied it. Terminate with 1216 * a fatal alert because if application tried to 1217 * renegotiatie it presumably had a good reason and 1218 * expects it to succeed. 1219 * 1220 * In future we might have a renegotiation where we 1221 * don't care if the peer refused it where we carry on. 1222 */ 1223 else if (alert_descr == SSL_AD_NO_RENEGOTIATION) 1224 { 1225 al = SSL_AD_HANDSHAKE_FAILURE; 1226 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_NO_RENEGOTIATION); 1227 goto f_err; 1228 } 1229 } 1230 else if (alert_level == 2) /* fatal */ 1231 { 1232 char tmp[16]; 1233 1234 s->rwstate=SSL_NOTHING; 1235 s->s3->fatal_alert = alert_descr; 1236 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_AD_REASON_OFFSET + alert_descr); 1237 BIO_snprintf(tmp,sizeof tmp,"%d",alert_descr); 1238 ERR_add_error_data(2,"SSL alert number ",tmp); 1239 s->shutdown|=SSL_RECEIVED_SHUTDOWN; 1240 SSL_CTX_remove_session(s->ctx,s->session); 1241 return(0); 1242 } 1243 else 1244 { 1245 al=SSL_AD_ILLEGAL_PARAMETER; 1246 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNKNOWN_ALERT_TYPE); 1247 goto f_err; 1248 } 1249 1250 goto start; 1251 } 1252 1253 if (s->shutdown & SSL_SENT_SHUTDOWN) /* but we have not received a shutdown */ 1254 { 1255 s->rwstate=SSL_NOTHING; 1256 rr->length=0; 1257 return(0); 1258 } 1259 1260 if (rr->type == SSL3_RT_CHANGE_CIPHER_SPEC) 1261 { 1262 /* 'Change Cipher Spec' is just a single byte, so we know 1263 * exactly what the record payload has to look like */ 1264 if ( (rr->length != 1) || (rr->off != 0) || 1265 (rr->data[0] != SSL3_MT_CCS)) 1266 { 1267 al=SSL_AD_ILLEGAL_PARAMETER; 1268 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_BAD_CHANGE_CIPHER_SPEC); 1269 goto f_err; 1270 } 1271 1272 /* Check we have a cipher to change to */ 1273 if (s->s3->tmp.new_cipher == NULL) 1274 { 1275 al=SSL_AD_UNEXPECTED_MESSAGE; 1276 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_CCS_RECEIVED_EARLY); 1277 goto f_err; 1278 } 1279 1280 if (!(s->s3->flags & SSL3_FLAGS_CCS_OK)) 1281 { 1282 al=SSL_AD_UNEXPECTED_MESSAGE; 1283 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_CCS_RECEIVED_EARLY); 1284 goto f_err; 1285 } 1286 1287 s->s3->flags &= ~SSL3_FLAGS_CCS_OK; 1288 1289 rr->length=0; 1290 1291 if (s->msg_callback) 1292 s->msg_callback(0, s->version, SSL3_RT_CHANGE_CIPHER_SPEC, rr->data, 1, s, s->msg_callback_arg); 1293 1294 s->s3->change_cipher_spec=1; 1295 if (!ssl3_do_change_cipher_spec(s)) 1296 goto err; 1297 else 1298 goto start; 1299 } 1300 1301 /* Unexpected handshake message (Client Hello, or protocol violation) */ 1302 if ((s->s3->handshake_fragment_len >= 4) && !s->in_handshake) 1303 { 1304 if (((s->state&SSL_ST_MASK) == SSL_ST_OK) && 1305 !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS)) 1306 { 1307#if 0 /* worked only because C operator preferences are not as expected (and 1308 * because this is not really needed for clients except for detecting 1309 * protocol violations): */ 1310 s->state=SSL_ST_BEFORE|(s->server) 1311 ?SSL_ST_ACCEPT 1312 :SSL_ST_CONNECT; 1313#else 1314 s->state = s->server ? SSL_ST_ACCEPT : SSL_ST_CONNECT; 1315#endif 1316 s->new_session=1; 1317 } 1318 i=s->handshake_func(s); 1319 if (i < 0) return(i); 1320 if (i == 0) 1321 { 1322 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE); 1323 return(-1); 1324 } 1325 1326 if (!(s->mode & SSL_MODE_AUTO_RETRY)) 1327 { 1328 if (s->s3->rbuf.left == 0) /* no read-ahead left? */ 1329 { 1330 BIO *bio; 1331 /* In the case where we try to read application data, 1332 * but we trigger an SSL handshake, we return -1 with 1333 * the retry option set. Otherwise renegotiation may 1334 * cause nasty problems in the blocking world */ 1335 s->rwstate=SSL_READING; 1336 bio=SSL_get_rbio(s); 1337 BIO_clear_retry_flags(bio); 1338 BIO_set_retry_read(bio); 1339 return(-1); 1340 } 1341 } 1342 goto start; 1343 } 1344 1345 switch (rr->type) 1346 { 1347 default: 1348#ifndef OPENSSL_NO_TLS 1349 /* TLS just ignores unknown message types */ 1350 if (s->version == TLS1_VERSION) 1351 { 1352 rr->length = 0; 1353 goto start; 1354 } 1355#endif 1356 al=SSL_AD_UNEXPECTED_MESSAGE; 1357 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNEXPECTED_RECORD); 1358 goto f_err; 1359 case SSL3_RT_CHANGE_CIPHER_SPEC: 1360 case SSL3_RT_ALERT: 1361 case SSL3_RT_HANDSHAKE: 1362 /* we already handled all of these, with the possible exception 1363 * of SSL3_RT_HANDSHAKE when s->in_handshake is set, but that 1364 * should not happen when type != rr->type */ 1365 al=SSL_AD_UNEXPECTED_MESSAGE; 1366 SSLerr(SSL_F_SSL3_READ_BYTES,ERR_R_INTERNAL_ERROR); 1367 goto f_err; 1368 case SSL3_RT_APPLICATION_DATA: 1369 /* At this point, we were expecting handshake data, 1370 * but have application data. If the library was 1371 * running inside ssl3_read() (i.e. in_read_app_data 1372 * is set) and it makes sense to read application data 1373 * at this point (session renegotiation not yet started), 1374 * we will indulge it. 1375 */ 1376 if (s->s3->in_read_app_data && 1377 (s->s3->total_renegotiations != 0) && 1378 (( 1379 (s->state & SSL_ST_CONNECT) && 1380 (s->state >= SSL3_ST_CW_CLNT_HELLO_A) && 1381 (s->state <= SSL3_ST_CR_SRVR_HELLO_A) 1382 ) || ( 1383 (s->state & SSL_ST_ACCEPT) && 1384 (s->state <= SSL3_ST_SW_HELLO_REQ_A) && 1385 (s->state >= SSL3_ST_SR_CLNT_HELLO_A) 1386 ) 1387 )) 1388 { 1389 s->s3->in_read_app_data=2; 1390 return(-1); 1391 } 1392 else 1393 { 1394 al=SSL_AD_UNEXPECTED_MESSAGE; 1395 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNEXPECTED_RECORD); 1396 goto f_err; 1397 } 1398 } 1399 /* not reached */ 1400 1401f_err: 1402 ssl3_send_alert(s,SSL3_AL_FATAL,al); 1403err: 1404 return(-1); 1405 } 1406 1407int ssl3_do_change_cipher_spec(SSL *s) 1408 { 1409 int i; 1410 const char *sender; 1411 int slen; 1412 1413 if (s->state & SSL_ST_ACCEPT) 1414 i=SSL3_CHANGE_CIPHER_SERVER_READ; 1415 else 1416 i=SSL3_CHANGE_CIPHER_CLIENT_READ; 1417 1418 if (s->s3->tmp.key_block == NULL) 1419 { 1420 if (s->session == NULL || s->session->master_key_length == 0) 1421 { 1422 /* might happen if dtls1_read_bytes() calls this */ 1423 SSLerr(SSL_F_SSL3_DO_CHANGE_CIPHER_SPEC,SSL_R_CCS_RECEIVED_EARLY); 1424 return (0); 1425 } 1426 1427 s->session->cipher=s->s3->tmp.new_cipher; 1428 if (!s->method->ssl3_enc->setup_key_block(s)) return(0); 1429 } 1430 1431 if (!s->method->ssl3_enc->change_cipher_state(s,i)) 1432 return(0); 1433 1434 /* we have to record the message digest at 1435 * this point so we can get it before we read 1436 * the finished message */ 1437 if (s->state & SSL_ST_CONNECT) 1438 { 1439 sender=s->method->ssl3_enc->server_finished_label; 1440 slen=s->method->ssl3_enc->server_finished_label_len; 1441 } 1442 else 1443 { 1444 sender=s->method->ssl3_enc->client_finished_label; 1445 slen=s->method->ssl3_enc->client_finished_label_len; 1446 } 1447 1448 s->s3->tmp.peer_finish_md_len = s->method->ssl3_enc->final_finish_mac(s, 1449 sender,slen,s->s3->tmp.peer_finish_md); 1450 1451 return(1); 1452 } 1453 1454int ssl3_send_alert(SSL *s, int level, int desc) 1455 { 1456 /* Map tls/ssl alert value to correct one */ 1457 desc=s->method->ssl3_enc->alert_value(desc); 1458 if (s->version == SSL3_VERSION && desc == SSL_AD_PROTOCOL_VERSION) 1459 desc = SSL_AD_HANDSHAKE_FAILURE; /* SSL 3.0 does not have protocol_version alerts */ 1460 if (desc < 0) return -1; 1461 /* If a fatal one, remove from cache */ 1462 if ((level == 2) && (s->session != NULL)) 1463 SSL_CTX_remove_session(s->ctx,s->session); 1464 1465 s->s3->alert_dispatch=1; 1466 s->s3->send_alert[0]=level; 1467 s->s3->send_alert[1]=desc; 1468 if (s->s3->wbuf.left == 0) /* data still being written out? */ 1469 return s->method->ssl_dispatch_alert(s); 1470 /* else data is still being written out, we will get written 1471 * some time in the future */ 1472 return -1; 1473 } 1474 1475int ssl3_dispatch_alert(SSL *s) 1476 { 1477 int i,j; 1478 void (*cb)(const SSL *ssl,int type,int val)=NULL; 1479 1480 s->s3->alert_dispatch=0; 1481 i = do_ssl3_write(s, SSL3_RT_ALERT, &s->s3->send_alert[0], 2, 0); 1482 if (i <= 0) 1483 { 1484 s->s3->alert_dispatch=1; 1485 } 1486 else 1487 { 1488 /* Alert sent to BIO. If it is important, flush it now. 1489 * If the message does not get sent due to non-blocking IO, 1490 * we will not worry too much. */ 1491 if (s->s3->send_alert[0] == SSL3_AL_FATAL) 1492 (void)BIO_flush(s->wbio); 1493 1494 if (s->msg_callback) 1495 s->msg_callback(1, s->version, SSL3_RT_ALERT, s->s3->send_alert, 2, s, s->msg_callback_arg); 1496 1497 if (s->info_callback != NULL) 1498 cb=s->info_callback; 1499 else if (s->ctx->info_callback != NULL) 1500 cb=s->ctx->info_callback; 1501 1502 if (cb != NULL) 1503 { 1504 j=(s->s3->send_alert[0]<<8)|s->s3->send_alert[1]; 1505 cb(s,SSL_CB_WRITE_ALERT,j); 1506 } 1507 } 1508 return(i); 1509 } 1510