s3_pkt.c revision 265124
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 <errno.h> 114#define USE_SOCKETS 115#include "ssl_locl.h" 116#include <openssl/evp.h> 117#include <openssl/buffer.h> 118#include <openssl/rand.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 && n > left) 186 n = left; 187 } 188 189 /* if there is enough in the buffer from a previous read, take some */ 190 if (left >= n) 191 { 192 s->packet_length+=n; 193 rb->left=left-n; 194 rb->offset+=n; 195 return(n); 196 } 197 198 /* else we need to read more data */ 199 200 len = s->packet_length; 201 pkt = rb->buf+align; 202 /* Move any available bytes to front of buffer: 203 * 'len' bytes already pointed to by 'packet', 204 * 'left' extra ones at the end */ 205 if (s->packet != pkt) /* len > 0 */ 206 { 207 memmove(pkt, s->packet, len+left); 208 s->packet = pkt; 209 rb->offset = len + align; 210 } 211 212 if (n > (int)(rb->len - rb->offset)) /* does not happen */ 213 { 214 SSLerr(SSL_F_SSL3_READ_N,ERR_R_INTERNAL_ERROR); 215 return -1; 216 } 217 218 if (!s->read_ahead) 219 /* ignore max parameter */ 220 max = n; 221 else 222 { 223 if (max < n) 224 max = n; 225 if (max > (int)(rb->len - rb->offset)) 226 max = rb->len - rb->offset; 227 } 228 229 while (left < n) 230 { 231 /* Now we have len+left bytes at the front of s->s3->rbuf.buf 232 * and need to read in more until we have len+n (up to 233 * len+max if possible) */ 234 235 clear_sys_error(); 236 if (s->rbio != NULL) 237 { 238 s->rwstate=SSL_READING; 239 i=BIO_read(s->rbio,pkt+len+left, max-left); 240 } 241 else 242 { 243 SSLerr(SSL_F_SSL3_READ_N,SSL_R_READ_BIO_NOT_SET); 244 i = -1; 245 } 246 247 if (i <= 0) 248 { 249 rb->left = left; 250 if (s->mode & SSL_MODE_RELEASE_BUFFERS && 251 SSL_version(s) != DTLS1_VERSION && SSL_version(s) != DTLS1_BAD_VER) 252 if (len+left == 0) 253 ssl3_release_read_buffer(s); 254 return(i); 255 } 256 left+=i; 257 /* reads should *never* span multiple packets for DTLS because 258 * the underlying transport protocol is message oriented as opposed 259 * to byte oriented as in the TLS case. */ 260 if (SSL_version(s) == DTLS1_VERSION || SSL_version(s) == DTLS1_BAD_VER) 261 { 262 if (n > left) 263 n = left; /* makes the while condition false */ 264 } 265 } 266 267 /* done reading, now the book-keeping */ 268 rb->offset += n; 269 rb->left = left - n; 270 s->packet_length += n; 271 s->rwstate=SSL_NOTHING; 272 return(n); 273 } 274 275/* Call this to get a new input record. 276 * It will return <= 0 if more data is needed, normally due to an error 277 * or non-blocking IO. 278 * When it finishes, one packet has been decoded and can be found in 279 * ssl->s3->rrec.type - is the type of record 280 * ssl->s3->rrec.data, - data 281 * ssl->s3->rrec.length, - number of bytes 282 */ 283/* used only by ssl3_read_bytes */ 284static int ssl3_get_record(SSL *s) 285 { 286 int ssl_major,ssl_minor,al; 287 int enc_err,n,i,ret= -1; 288 SSL3_RECORD *rr; 289 SSL_SESSION *sess; 290 unsigned char *p; 291 unsigned char md[EVP_MAX_MD_SIZE]; 292 short version; 293 unsigned mac_size, orig_len; 294 size_t extra; 295 296 rr= &(s->s3->rrec); 297 sess=s->session; 298 299 if (s->options & SSL_OP_MICROSOFT_BIG_SSLV3_BUFFER) 300 extra=SSL3_RT_MAX_EXTRA; 301 else 302 extra=0; 303 if (extra && !s->s3->init_extra) 304 { 305 /* An application error: SLS_OP_MICROSOFT_BIG_SSLV3_BUFFER 306 * set after ssl3_setup_buffers() was done */ 307 SSLerr(SSL_F_SSL3_GET_RECORD, ERR_R_INTERNAL_ERROR); 308 return -1; 309 } 310 311again: 312 /* check if we have the header */ 313 if ( (s->rstate != SSL_ST_READ_BODY) || 314 (s->packet_length < SSL3_RT_HEADER_LENGTH)) 315 { 316 n=ssl3_read_n(s, SSL3_RT_HEADER_LENGTH, s->s3->rbuf.len, 0); 317 if (n <= 0) return(n); /* error or non-blocking */ 318 s->rstate=SSL_ST_READ_BODY; 319 320 p=s->packet; 321 322 /* Pull apart the header into the SSL3_RECORD */ 323 rr->type= *(p++); 324 ssl_major= *(p++); 325 ssl_minor= *(p++); 326 version=(ssl_major<<8)|ssl_minor; 327 n2s(p,rr->length); 328#if 0 329fprintf(stderr, "Record type=%d, Length=%d\n", rr->type, rr->length); 330#endif 331 332 /* Lets check version */ 333 if (!s->first_packet) 334 { 335 if (version != s->version) 336 { 337 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_WRONG_VERSION_NUMBER); 338 if ((s->version & 0xFF00) == (version & 0xFF00)) 339 /* Send back error using their minor version number :-) */ 340 s->version = (unsigned short)version; 341 al=SSL_AD_PROTOCOL_VERSION; 342 goto f_err; 343 } 344 } 345 346 if ((version>>8) != SSL3_VERSION_MAJOR) 347 { 348 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_WRONG_VERSION_NUMBER); 349 goto err; 350 } 351 352 if (rr->length > s->s3->rbuf.len - SSL3_RT_HEADER_LENGTH) 353 { 354 al=SSL_AD_RECORD_OVERFLOW; 355 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_PACKET_LENGTH_TOO_LONG); 356 goto f_err; 357 } 358 359 /* now s->rstate == SSL_ST_READ_BODY */ 360 } 361 362 /* s->rstate == SSL_ST_READ_BODY, get and decode the data */ 363 364 if (rr->length > s->packet_length-SSL3_RT_HEADER_LENGTH) 365 { 366 /* now s->packet_length == SSL3_RT_HEADER_LENGTH */ 367 i=rr->length; 368 n=ssl3_read_n(s,i,i,1); 369 if (n <= 0) return(n); /* error or non-blocking io */ 370 /* now n == rr->length, 371 * and s->packet_length == SSL3_RT_HEADER_LENGTH + rr->length */ 372 } 373 374 s->rstate=SSL_ST_READ_HEADER; /* set state for later operations */ 375 376 /* At this point, s->packet_length == SSL3_RT_HEADER_LNGTH + rr->length, 377 * and we have that many bytes in s->packet 378 */ 379 rr->input= &(s->packet[SSL3_RT_HEADER_LENGTH]); 380 381 /* ok, we can now read from 's->packet' data into 'rr' 382 * rr->input points at rr->length bytes, which 383 * need to be copied into rr->data by either 384 * the decryption or by the decompression 385 * When the data is 'copied' into the rr->data buffer, 386 * rr->input will be pointed at the new buffer */ 387 388 /* We now have - encrypted [ MAC [ compressed [ plain ] ] ] 389 * rr->length bytes of encrypted compressed stuff. */ 390 391 /* check is not needed I believe */ 392 if (rr->length > SSL3_RT_MAX_ENCRYPTED_LENGTH+extra) 393 { 394 al=SSL_AD_RECORD_OVERFLOW; 395 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_ENCRYPTED_LENGTH_TOO_LONG); 396 goto f_err; 397 } 398 399 /* decrypt in place in 'rr->input' */ 400 rr->data=rr->input; 401 402 enc_err = s->method->ssl3_enc->enc(s,0); 403 /* enc_err is: 404 * 0: (in non-constant time) if the record is publically invalid. 405 * 1: if the padding is valid 406 * -1: if the padding is invalid */ 407 if (enc_err == 0) 408 { 409 al=SSL_AD_DECRYPTION_FAILED; 410 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_BLOCK_CIPHER_PAD_IS_WRONG); 411 goto f_err; 412 } 413 414#ifdef TLS_DEBUG 415printf("dec %d\n",rr->length); 416{ unsigned int z; for (z=0; z<rr->length; z++) printf("%02X%c",rr->data[z],((z+1)%16)?' ':'\n'); } 417printf("\n"); 418#endif 419 420 /* r->length is now the compressed data plus mac */ 421 if ((sess != NULL) && 422 (s->enc_read_ctx != NULL) && 423 (EVP_MD_CTX_md(s->read_hash) != NULL)) 424 { 425 /* s->read_hash != NULL => mac_size != -1 */ 426 unsigned char *mac = NULL; 427 unsigned char mac_tmp[EVP_MAX_MD_SIZE]; 428 mac_size=EVP_MD_CTX_size(s->read_hash); 429 OPENSSL_assert(mac_size <= EVP_MAX_MD_SIZE); 430 431 /* kludge: *_cbc_remove_padding passes padding length in rr->type */ 432 orig_len = rr->length+((unsigned int)rr->type>>8); 433 434 /* orig_len is the length of the record before any padding was 435 * removed. This is public information, as is the MAC in use, 436 * therefore we can safely process the record in a different 437 * amount of time if it's too short to possibly contain a MAC. 438 */ 439 if (orig_len < mac_size || 440 /* CBC records must have a padding length byte too. */ 441 (EVP_CIPHER_CTX_mode(s->enc_read_ctx) == EVP_CIPH_CBC_MODE && 442 orig_len < mac_size+1)) 443 { 444 al=SSL_AD_DECODE_ERROR; 445 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_LENGTH_TOO_SHORT); 446 goto f_err; 447 } 448 449 if (EVP_CIPHER_CTX_mode(s->enc_read_ctx) == EVP_CIPH_CBC_MODE) 450 { 451 /* We update the length so that the TLS header bytes 452 * can be constructed correctly but we need to extract 453 * the MAC in constant time from within the record, 454 * without leaking the contents of the padding bytes. 455 * */ 456 mac = mac_tmp; 457 ssl3_cbc_copy_mac(mac_tmp, rr, mac_size, orig_len); 458 rr->length -= mac_size; 459 } 460 else 461 { 462 /* In this case there's no padding, so |orig_len| 463 * equals |rec->length| and we checked that there's 464 * enough bytes for |mac_size| above. */ 465 rr->length -= mac_size; 466 mac = &rr->data[rr->length]; 467 } 468 469 i=s->method->ssl3_enc->mac(s,md,0 /* not send */); 470 if (i < 0 || mac == NULL || CRYPTO_memcmp(md, mac, (size_t)mac_size) != 0) 471 enc_err = -1; 472 if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH+extra+mac_size) 473 enc_err = -1; 474 } 475 476 if (enc_err < 0) 477 { 478 /* A separate 'decryption_failed' alert was introduced with TLS 1.0, 479 * SSL 3.0 only has 'bad_record_mac'. But unless a decryption 480 * failure is directly visible from the ciphertext anyway, 481 * we should not reveal which kind of error occured -- this 482 * might become visible to an attacker (e.g. via a logfile) */ 483 al=SSL_AD_BAD_RECORD_MAC; 484 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_DECRYPTION_FAILED_OR_BAD_RECORD_MAC); 485 goto f_err; 486 } 487 488 /* r->length is now just compressed */ 489 if (s->expand != NULL) 490 { 491 if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH+extra) 492 { 493 al=SSL_AD_RECORD_OVERFLOW; 494 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_COMPRESSED_LENGTH_TOO_LONG); 495 goto f_err; 496 } 497 if (!ssl3_do_uncompress(s)) 498 { 499 al=SSL_AD_DECOMPRESSION_FAILURE; 500 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_BAD_DECOMPRESSION); 501 goto f_err; 502 } 503 } 504 505 if (rr->length > SSL3_RT_MAX_PLAIN_LENGTH+extra) 506 { 507 al=SSL_AD_RECORD_OVERFLOW; 508 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_DATA_LENGTH_TOO_LONG); 509 goto f_err; 510 } 511 512 rr->off=0; 513 /* So at this point the following is true 514 * ssl->s3->rrec.type is the type of record 515 * ssl->s3->rrec.length == number of bytes in record 516 * ssl->s3->rrec.off == offset to first valid byte 517 * ssl->s3->rrec.data == where to take bytes from, increment 518 * after use :-). 519 */ 520 521 /* we have pulled in a full packet so zero things */ 522 s->packet_length=0; 523 524 /* just read a 0 length packet */ 525 if (rr->length == 0) goto again; 526 527#if 0 528fprintf(stderr, "Ultimate Record type=%d, Length=%d\n", rr->type, rr->length); 529#endif 530 531 return(1); 532 533f_err: 534 ssl3_send_alert(s,SSL3_AL_FATAL,al); 535err: 536 return(ret); 537 } 538 539int ssl3_do_uncompress(SSL *ssl) 540 { 541#ifndef OPENSSL_NO_COMP 542 int i; 543 SSL3_RECORD *rr; 544 545 rr= &(ssl->s3->rrec); 546 i=COMP_expand_block(ssl->expand,rr->comp, 547 SSL3_RT_MAX_PLAIN_LENGTH,rr->data,(int)rr->length); 548 if (i < 0) 549 return(0); 550 else 551 rr->length=i; 552 rr->data=rr->comp; 553#endif 554 return(1); 555 } 556 557int ssl3_do_compress(SSL *ssl) 558 { 559#ifndef OPENSSL_NO_COMP 560 int i; 561 SSL3_RECORD *wr; 562 563 wr= &(ssl->s3->wrec); 564 i=COMP_compress_block(ssl->compress,wr->data, 565 SSL3_RT_MAX_COMPRESSED_LENGTH, 566 wr->input,(int)wr->length); 567 if (i < 0) 568 return(0); 569 else 570 wr->length=i; 571 572 wr->input=wr->data; 573#endif 574 return(1); 575 } 576 577/* Call this to write data in records of type 'type' 578 * It will return <= 0 if not all data has been sent or non-blocking IO. 579 */ 580int ssl3_write_bytes(SSL *s, int type, const void *buf_, int len) 581 { 582 const unsigned char *buf=buf_; 583 unsigned int tot,n,nw; 584 int i; 585 586 s->rwstate=SSL_NOTHING; 587 tot=s->s3->wnum; 588 s->s3->wnum=0; 589 590 if (SSL_in_init(s) && !s->in_handshake) 591 { 592 i=s->handshake_func(s); 593 if (i < 0) return(i); 594 if (i == 0) 595 { 596 SSLerr(SSL_F_SSL3_WRITE_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE); 597 return -1; 598 } 599 } 600 601 n=(len-tot); 602 for (;;) 603 { 604 if (n > s->max_send_fragment) 605 nw=s->max_send_fragment; 606 else 607 nw=n; 608 609 i=do_ssl3_write(s, type, &(buf[tot]), nw, 0); 610 if (i <= 0) 611 { 612 s->s3->wnum=tot; 613 return i; 614 } 615 616 if ((i == (int)n) || 617 (type == SSL3_RT_APPLICATION_DATA && 618 (s->mode & SSL_MODE_ENABLE_PARTIAL_WRITE))) 619 { 620 /* next chunk of data should get another prepended empty fragment 621 * in ciphersuites with known-IV weakness: */ 622 s->s3->empty_fragment_done = 0; 623 624 return tot+i; 625 } 626 627 n-=i; 628 tot+=i; 629 } 630 } 631 632static int do_ssl3_write(SSL *s, int type, const unsigned char *buf, 633 unsigned int len, int create_empty_fragment) 634 { 635 unsigned char *p,*plen; 636 int i,mac_size,clear=0; 637 int prefix_len=0; 638 int eivlen; 639 long align=0; 640 SSL3_RECORD *wr; 641 SSL3_BUFFER *wb=&(s->s3->wbuf); 642 SSL_SESSION *sess; 643 644 if (wb->buf == NULL) 645 if (!ssl3_setup_write_buffer(s)) 646 return -1; 647 648 /* first check if there is a SSL3_BUFFER still being written 649 * out. This will happen with non blocking IO */ 650 if (wb->left != 0) 651 return(ssl3_write_pending(s,type,buf,len)); 652 653 /* If we have an alert to send, lets send it */ 654 if (s->s3->alert_dispatch) 655 { 656 i=s->method->ssl_dispatch_alert(s); 657 if (i <= 0) 658 return(i); 659 /* if it went, fall through and send more stuff */ 660 } 661 662 if (len == 0 && !create_empty_fragment) 663 return 0; 664 665 wr= &(s->s3->wrec); 666 sess=s->session; 667 668 if ( (sess == NULL) || 669 (s->enc_write_ctx == NULL) || 670 (EVP_MD_CTX_md(s->write_hash) == NULL)) 671 { 672#if 1 673 clear=s->enc_write_ctx?0:1; /* must be AEAD cipher */ 674#else 675 clear=1; 676#endif 677 mac_size=0; 678 } 679 else 680 { 681 mac_size=EVP_MD_CTX_size(s->write_hash); 682 if (mac_size < 0) 683 goto err; 684 } 685 686 /* 'create_empty_fragment' is true only when this function calls itself */ 687 if (!clear && !create_empty_fragment && !s->s3->empty_fragment_done) 688 { 689 /* countermeasure against known-IV weakness in CBC ciphersuites 690 * (see http://www.openssl.org/~bodo/tls-cbc.txt) */ 691 692 if (s->s3->need_empty_fragments && type == SSL3_RT_APPLICATION_DATA) 693 { 694 /* recursive function call with 'create_empty_fragment' set; 695 * this prepares and buffers the data for an empty fragment 696 * (these 'prefix_len' bytes are sent out later 697 * together with the actual payload) */ 698 prefix_len = do_ssl3_write(s, type, buf, 0, 1); 699 if (prefix_len <= 0) 700 goto err; 701 702 if (prefix_len > 703 (SSL3_RT_HEADER_LENGTH + SSL3_RT_SEND_MAX_ENCRYPTED_OVERHEAD)) 704 { 705 /* insufficient space */ 706 SSLerr(SSL_F_DO_SSL3_WRITE, ERR_R_INTERNAL_ERROR); 707 goto err; 708 } 709 } 710 711 s->s3->empty_fragment_done = 1; 712 } 713 714 if (create_empty_fragment) 715 { 716#if defined(SSL3_ALIGN_PAYLOAD) && SSL3_ALIGN_PAYLOAD!=0 717 /* extra fragment would be couple of cipher blocks, 718 * which would be multiple of SSL3_ALIGN_PAYLOAD, so 719 * if we want to align the real payload, then we can 720 * just pretent we simply have two headers. */ 721 align = (long)wb->buf + 2*SSL3_RT_HEADER_LENGTH; 722 align = (-align)&(SSL3_ALIGN_PAYLOAD-1); 723#endif 724 p = wb->buf + align; 725 wb->offset = align; 726 } 727 else if (prefix_len) 728 { 729 p = wb->buf + wb->offset + prefix_len; 730 } 731 else 732 { 733#if defined(SSL3_ALIGN_PAYLOAD) && SSL3_ALIGN_PAYLOAD!=0 734 align = (long)wb->buf + SSL3_RT_HEADER_LENGTH; 735 align = (-align)&(SSL3_ALIGN_PAYLOAD-1); 736#endif 737 p = wb->buf + align; 738 wb->offset = align; 739 } 740 741 /* write the header */ 742 743 *(p++)=type&0xff; 744 wr->type=type; 745 746 *(p++)=(s->version>>8); 747 /* Some servers hang if iniatial client hello is larger than 256 748 * bytes and record version number > TLS 1.0 749 */ 750 if (s->state == SSL3_ST_CW_CLNT_HELLO_B 751 && !s->renegotiate 752 && TLS1_get_version(s) > TLS1_VERSION) 753 *(p++) = 0x1; 754 else 755 *(p++)=s->version&0xff; 756 757 /* field where we are to write out packet length */ 758 plen=p; 759 p+=2; 760 /* Explicit IV length, block ciphers and TLS version 1.1 or later */ 761 if (s->enc_write_ctx && s->version >= TLS1_1_VERSION) 762 { 763 int mode = EVP_CIPHER_CTX_mode(s->enc_write_ctx); 764 if (mode == EVP_CIPH_CBC_MODE) 765 { 766 eivlen = EVP_CIPHER_CTX_iv_length(s->enc_write_ctx); 767 if (eivlen <= 1) 768 eivlen = 0; 769 } 770 /* Need explicit part of IV for GCM mode */ 771 else if (mode == EVP_CIPH_GCM_MODE) 772 eivlen = EVP_GCM_TLS_EXPLICIT_IV_LEN; 773 else 774 eivlen = 0; 775 } 776 else 777 eivlen = 0; 778 779 /* lets setup the record stuff. */ 780 wr->data=p + eivlen; 781 wr->length=(int)len; 782 wr->input=(unsigned char *)buf; 783 784 /* we now 'read' from wr->input, wr->length bytes into 785 * wr->data */ 786 787 /* first we compress */ 788 if (s->compress != NULL) 789 { 790 if (!ssl3_do_compress(s)) 791 { 792 SSLerr(SSL_F_DO_SSL3_WRITE,SSL_R_COMPRESSION_FAILURE); 793 goto err; 794 } 795 } 796 else 797 { 798 memcpy(wr->data,wr->input,wr->length); 799 wr->input=wr->data; 800 } 801 802 /* we should still have the output to wr->data and the input 803 * from wr->input. Length should be wr->length. 804 * wr->data still points in the wb->buf */ 805 806 if (mac_size != 0) 807 { 808 if (s->method->ssl3_enc->mac(s,&(p[wr->length + eivlen]),1) < 0) 809 goto err; 810 wr->length+=mac_size; 811 } 812 813 wr->input=p; 814 wr->data=p; 815 816 if (eivlen) 817 { 818 /* if (RAND_pseudo_bytes(p, eivlen) <= 0) 819 goto err; */ 820 wr->length += eivlen; 821 } 822 823 /* ssl3_enc can only have an error on read */ 824 s->method->ssl3_enc->enc(s,1); 825 826 /* record length after mac and block padding */ 827 s2n(wr->length,plen); 828 829 /* we should now have 830 * wr->data pointing to the encrypted data, which is 831 * wr->length long */ 832 wr->type=type; /* not needed but helps for debugging */ 833 wr->length+=SSL3_RT_HEADER_LENGTH; 834 835 if (create_empty_fragment) 836 { 837 /* we are in a recursive call; 838 * just return the length, don't write out anything here 839 */ 840 return wr->length; 841 } 842 843 /* now let's set up wb */ 844 wb->left = prefix_len + wr->length; 845 846 /* memorize arguments so that ssl3_write_pending can detect bad write retries later */ 847 s->s3->wpend_tot=len; 848 s->s3->wpend_buf=buf; 849 s->s3->wpend_type=type; 850 s->s3->wpend_ret=len; 851 852 /* we now just need to write the buffer */ 853 return ssl3_write_pending(s,type,buf,len); 854err: 855 return -1; 856 } 857 858/* if s->s3->wbuf.left != 0, we need to call this */ 859int ssl3_write_pending(SSL *s, int type, const unsigned char *buf, 860 unsigned int len) 861 { 862 int i; 863 SSL3_BUFFER *wb=&(s->s3->wbuf); 864 865/* XXXX */ 866 if ((s->s3->wpend_tot > (int)len) 867 || ((s->s3->wpend_buf != buf) && 868 !(s->mode & SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER)) 869 || (s->s3->wpend_type != type)) 870 { 871 SSLerr(SSL_F_SSL3_WRITE_PENDING,SSL_R_BAD_WRITE_RETRY); 872 return(-1); 873 } 874 875 for (;;) 876 { 877 clear_sys_error(); 878 if (s->wbio != NULL) 879 { 880 s->rwstate=SSL_WRITING; 881 i=BIO_write(s->wbio, 882 (char *)&(wb->buf[wb->offset]), 883 (unsigned int)wb->left); 884 } 885 else 886 { 887 SSLerr(SSL_F_SSL3_WRITE_PENDING,SSL_R_BIO_NOT_SET); 888 i= -1; 889 } 890 if (i == wb->left) 891 { 892 wb->left=0; 893 wb->offset+=i; 894 if (s->mode & SSL_MODE_RELEASE_BUFFERS && 895 SSL_version(s) != DTLS1_VERSION && SSL_version(s) != DTLS1_BAD_VER) 896 ssl3_release_write_buffer(s); 897 s->rwstate=SSL_NOTHING; 898 return(s->s3->wpend_ret); 899 } 900 else if (i <= 0) { 901 if (s->version == DTLS1_VERSION || 902 s->version == DTLS1_BAD_VER) { 903 /* For DTLS, just drop it. That's kind of the whole 904 point in using a datagram service */ 905 wb->left = 0; 906 } 907 return(i); 908 } 909 wb->offset+=i; 910 wb->left-=i; 911 } 912 } 913 914/* Return up to 'len' payload bytes received in 'type' records. 915 * 'type' is one of the following: 916 * 917 * - SSL3_RT_HANDSHAKE (when ssl3_get_message calls us) 918 * - SSL3_RT_APPLICATION_DATA (when ssl3_read calls us) 919 * - 0 (during a shutdown, no data has to be returned) 920 * 921 * If we don't have stored data to work from, read a SSL/TLS record first 922 * (possibly multiple records if we still don't have anything to return). 923 * 924 * This function must handle any surprises the peer may have for us, such as 925 * Alert records (e.g. close_notify), ChangeCipherSpec records (not really 926 * a surprise, but handled as if it were), or renegotiation requests. 927 * Also if record payloads contain fragments too small to process, we store 928 * them until there is enough for the respective protocol (the record protocol 929 * may use arbitrary fragmentation and even interleaving): 930 * Change cipher spec protocol 931 * just 1 byte needed, no need for keeping anything stored 932 * Alert protocol 933 * 2 bytes needed (AlertLevel, AlertDescription) 934 * Handshake protocol 935 * 4 bytes needed (HandshakeType, uint24 length) -- we just have 936 * to detect unexpected Client Hello and Hello Request messages 937 * here, anything else is handled by higher layers 938 * Application data protocol 939 * none of our business 940 */ 941int ssl3_read_bytes(SSL *s, int type, unsigned char *buf, int len, int peek) 942 { 943 int al,i,j,ret; 944 unsigned int n; 945 SSL3_RECORD *rr; 946 void (*cb)(const SSL *ssl,int type2,int val)=NULL; 947 948 if (s->s3->rbuf.buf == NULL) /* Not initialized yet */ 949 if (!ssl3_setup_read_buffer(s)) 950 return(-1); 951 952 if ((type && (type != SSL3_RT_APPLICATION_DATA) && (type != SSL3_RT_HANDSHAKE) && type) || 953 (peek && (type != SSL3_RT_APPLICATION_DATA))) 954 { 955 SSLerr(SSL_F_SSL3_READ_BYTES, ERR_R_INTERNAL_ERROR); 956 return -1; 957 } 958 959 if ((type == SSL3_RT_HANDSHAKE) && (s->s3->handshake_fragment_len > 0)) 960 /* (partially) satisfy request from storage */ 961 { 962 unsigned char *src = s->s3->handshake_fragment; 963 unsigned char *dst = buf; 964 unsigned int k; 965 966 /* peek == 0 */ 967 n = 0; 968 while ((len > 0) && (s->s3->handshake_fragment_len > 0)) 969 { 970 *dst++ = *src++; 971 len--; s->s3->handshake_fragment_len--; 972 n++; 973 } 974 /* move any remaining fragment bytes: */ 975 for (k = 0; k < s->s3->handshake_fragment_len; k++) 976 s->s3->handshake_fragment[k] = *src++; 977 return n; 978 } 979 980 /* Now s->s3->handshake_fragment_len == 0 if type == SSL3_RT_HANDSHAKE. */ 981 982 if (!s->in_handshake && SSL_in_init(s)) 983 { 984 /* type == SSL3_RT_APPLICATION_DATA */ 985 i=s->handshake_func(s); 986 if (i < 0) return(i); 987 if (i == 0) 988 { 989 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE); 990 return(-1); 991 } 992 } 993start: 994 s->rwstate=SSL_NOTHING; 995 996 /* s->s3->rrec.type - is the type of record 997 * s->s3->rrec.data, - data 998 * s->s3->rrec.off, - offset into 'data' for next read 999 * s->s3->rrec.length, - number of bytes. */ 1000 rr = &(s->s3->rrec); 1001 1002 /* get new packet if necessary */ 1003 if ((rr->length == 0) || (s->rstate == SSL_ST_READ_BODY)) 1004 { 1005 ret=ssl3_get_record(s); 1006 if (ret <= 0) return(ret); 1007 } 1008 1009 /* we now have a packet which can be read and processed */ 1010 1011 if (s->s3->change_cipher_spec /* set when we receive ChangeCipherSpec, 1012 * reset by ssl3_get_finished */ 1013 && (rr->type != SSL3_RT_HANDSHAKE)) 1014 { 1015 al=SSL_AD_UNEXPECTED_MESSAGE; 1016 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_DATA_BETWEEN_CCS_AND_FINISHED); 1017 goto f_err; 1018 } 1019 1020 /* If the other end has shut down, throw anything we read away 1021 * (even in 'peek' mode) */ 1022 if (s->shutdown & SSL_RECEIVED_SHUTDOWN) 1023 { 1024 rr->length=0; 1025 s->rwstate=SSL_NOTHING; 1026 return(0); 1027 } 1028 1029 1030 if (type == rr->type) /* SSL3_RT_APPLICATION_DATA or SSL3_RT_HANDSHAKE */ 1031 { 1032 /* make sure that we are not getting application data when we 1033 * are doing a handshake for the first time */ 1034 if (SSL_in_init(s) && (type == SSL3_RT_APPLICATION_DATA) && 1035 (s->enc_read_ctx == NULL)) 1036 { 1037 al=SSL_AD_UNEXPECTED_MESSAGE; 1038 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_APP_DATA_IN_HANDSHAKE); 1039 goto f_err; 1040 } 1041 1042 if (len <= 0) return(len); 1043 1044 if ((unsigned int)len > rr->length) 1045 n = rr->length; 1046 else 1047 n = (unsigned int)len; 1048 1049 memcpy(buf,&(rr->data[rr->off]),n); 1050 if (!peek) 1051 { 1052 rr->length-=n; 1053 rr->off+=n; 1054 if (rr->length == 0) 1055 { 1056 s->rstate=SSL_ST_READ_HEADER; 1057 rr->off=0; 1058 if (s->mode & SSL_MODE_RELEASE_BUFFERS && s->s3->rbuf.left == 0) 1059 ssl3_release_read_buffer(s); 1060 } 1061 } 1062 return(n); 1063 } 1064 1065 1066 /* If we get here, then type != rr->type; if we have a handshake 1067 * message, then it was unexpected (Hello Request or Client Hello). */ 1068 1069 /* In case of record types for which we have 'fragment' storage, 1070 * fill that so that we can process the data at a fixed place. 1071 */ 1072 { 1073 unsigned int dest_maxlen = 0; 1074 unsigned char *dest = NULL; 1075 unsigned int *dest_len = NULL; 1076 1077 if (rr->type == SSL3_RT_HANDSHAKE) 1078 { 1079 dest_maxlen = sizeof s->s3->handshake_fragment; 1080 dest = s->s3->handshake_fragment; 1081 dest_len = &s->s3->handshake_fragment_len; 1082 } 1083 else if (rr->type == SSL3_RT_ALERT) 1084 { 1085 dest_maxlen = sizeof s->s3->alert_fragment; 1086 dest = s->s3->alert_fragment; 1087 dest_len = &s->s3->alert_fragment_len; 1088 } 1089#ifndef OPENSSL_NO_HEARTBEATS 1090 else if (rr->type == TLS1_RT_HEARTBEAT) 1091 { 1092 tls1_process_heartbeat(s); 1093 1094 /* Exit and notify application to read again */ 1095 rr->length = 0; 1096 s->rwstate=SSL_READING; 1097 BIO_clear_retry_flags(SSL_get_rbio(s)); 1098 BIO_set_retry_read(SSL_get_rbio(s)); 1099 return(-1); 1100 } 1101#endif 1102 1103 if (dest_maxlen > 0) 1104 { 1105 n = dest_maxlen - *dest_len; /* available space in 'dest' */ 1106 if (rr->length < n) 1107 n = rr->length; /* available bytes */ 1108 1109 /* now move 'n' bytes: */ 1110 while (n-- > 0) 1111 { 1112 dest[(*dest_len)++] = rr->data[rr->off++]; 1113 rr->length--; 1114 } 1115 1116 if (*dest_len < dest_maxlen) 1117 goto start; /* fragment was too small */ 1118 } 1119 } 1120 1121 /* s->s3->handshake_fragment_len == 4 iff rr->type == SSL3_RT_HANDSHAKE; 1122 * s->s3->alert_fragment_len == 2 iff rr->type == SSL3_RT_ALERT. 1123 * (Possibly rr is 'empty' now, i.e. rr->length may be 0.) */ 1124 1125 /* If we are a client, check for an incoming 'Hello Request': */ 1126 if ((!s->server) && 1127 (s->s3->handshake_fragment_len >= 4) && 1128 (s->s3->handshake_fragment[0] == SSL3_MT_HELLO_REQUEST) && 1129 (s->session != NULL) && (s->session->cipher != NULL)) 1130 { 1131 s->s3->handshake_fragment_len = 0; 1132 1133 if ((s->s3->handshake_fragment[1] != 0) || 1134 (s->s3->handshake_fragment[2] != 0) || 1135 (s->s3->handshake_fragment[3] != 0)) 1136 { 1137 al=SSL_AD_DECODE_ERROR; 1138 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_BAD_HELLO_REQUEST); 1139 goto f_err; 1140 } 1141 1142 if (s->msg_callback) 1143 s->msg_callback(0, s->version, SSL3_RT_HANDSHAKE, s->s3->handshake_fragment, 4, s, s->msg_callback_arg); 1144 1145 if (SSL_is_init_finished(s) && 1146 !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS) && 1147 !s->s3->renegotiate) 1148 { 1149 ssl3_renegotiate(s); 1150 if (ssl3_renegotiate_check(s)) 1151 { 1152 i=s->handshake_func(s); 1153 if (i < 0) return(i); 1154 if (i == 0) 1155 { 1156 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE); 1157 return(-1); 1158 } 1159 1160 if (!(s->mode & SSL_MODE_AUTO_RETRY)) 1161 { 1162 if (s->s3->rbuf.left == 0) /* no read-ahead left? */ 1163 { 1164 BIO *bio; 1165 /* In the case where we try to read application data, 1166 * but we trigger an SSL handshake, we return -1 with 1167 * the retry option set. Otherwise renegotiation may 1168 * cause nasty problems in the blocking world */ 1169 s->rwstate=SSL_READING; 1170 bio=SSL_get_rbio(s); 1171 BIO_clear_retry_flags(bio); 1172 BIO_set_retry_read(bio); 1173 return(-1); 1174 } 1175 } 1176 } 1177 } 1178 /* we either finished a handshake or ignored the request, 1179 * now try again to obtain the (application) data we were asked for */ 1180 goto start; 1181 } 1182 /* If we are a server and get a client hello when renegotiation isn't 1183 * allowed send back a no renegotiation alert and carry on. 1184 * WARNING: experimental code, needs reviewing (steve) 1185 */ 1186 if (s->server && 1187 SSL_is_init_finished(s) && 1188 !s->s3->send_connection_binding && 1189 (s->version > SSL3_VERSION) && 1190 (s->s3->handshake_fragment_len >= 4) && 1191 (s->s3->handshake_fragment[0] == SSL3_MT_CLIENT_HELLO) && 1192 (s->session != NULL) && (s->session->cipher != NULL) && 1193 !(s->ctx->options & SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION)) 1194 1195 { 1196 /*s->s3->handshake_fragment_len = 0;*/ 1197 rr->length = 0; 1198 ssl3_send_alert(s,SSL3_AL_WARNING, SSL_AD_NO_RENEGOTIATION); 1199 goto start; 1200 } 1201 if (s->s3->alert_fragment_len >= 2) 1202 { 1203 int alert_level = s->s3->alert_fragment[0]; 1204 int alert_descr = s->s3->alert_fragment[1]; 1205 1206 s->s3->alert_fragment_len = 0; 1207 1208 if (s->msg_callback) 1209 s->msg_callback(0, s->version, SSL3_RT_ALERT, s->s3->alert_fragment, 2, s, s->msg_callback_arg); 1210 1211 if (s->info_callback != NULL) 1212 cb=s->info_callback; 1213 else if (s->ctx->info_callback != NULL) 1214 cb=s->ctx->info_callback; 1215 1216 if (cb != NULL) 1217 { 1218 j = (alert_level << 8) | alert_descr; 1219 cb(s, SSL_CB_READ_ALERT, j); 1220 } 1221 1222 if (alert_level == 1) /* warning */ 1223 { 1224 s->s3->warn_alert = alert_descr; 1225 if (alert_descr == SSL_AD_CLOSE_NOTIFY) 1226 { 1227 s->shutdown |= SSL_RECEIVED_SHUTDOWN; 1228 return(0); 1229 } 1230 /* This is a warning but we receive it if we requested 1231 * renegotiation and the peer denied it. Terminate with 1232 * a fatal alert because if application tried to 1233 * renegotiatie it presumably had a good reason and 1234 * expects it to succeed. 1235 * 1236 * In future we might have a renegotiation where we 1237 * don't care if the peer refused it where we carry on. 1238 */ 1239 else if (alert_descr == SSL_AD_NO_RENEGOTIATION) 1240 { 1241 al = SSL_AD_HANDSHAKE_FAILURE; 1242 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_NO_RENEGOTIATION); 1243 goto f_err; 1244 } 1245#ifdef SSL_AD_MISSING_SRP_USERNAME 1246 else if (alert_descr == SSL_AD_MISSING_SRP_USERNAME) 1247 return(0); 1248#endif 1249 } 1250 else if (alert_level == 2) /* fatal */ 1251 { 1252 char tmp[16]; 1253 1254 s->rwstate=SSL_NOTHING; 1255 s->s3->fatal_alert = alert_descr; 1256 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_AD_REASON_OFFSET + alert_descr); 1257 BIO_snprintf(tmp,sizeof tmp,"%d",alert_descr); 1258 ERR_add_error_data(2,"SSL alert number ",tmp); 1259 s->shutdown|=SSL_RECEIVED_SHUTDOWN; 1260 SSL_CTX_remove_session(s->ctx,s->session); 1261 return(0); 1262 } 1263 else 1264 { 1265 al=SSL_AD_ILLEGAL_PARAMETER; 1266 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNKNOWN_ALERT_TYPE); 1267 goto f_err; 1268 } 1269 1270 goto start; 1271 } 1272 1273 if (s->shutdown & SSL_SENT_SHUTDOWN) /* but we have not received a shutdown */ 1274 { 1275 s->rwstate=SSL_NOTHING; 1276 rr->length=0; 1277 return(0); 1278 } 1279 1280 if (rr->type == SSL3_RT_CHANGE_CIPHER_SPEC) 1281 { 1282 /* 'Change Cipher Spec' is just a single byte, so we know 1283 * exactly what the record payload has to look like */ 1284 if ( (rr->length != 1) || (rr->off != 0) || 1285 (rr->data[0] != SSL3_MT_CCS)) 1286 { 1287 al=SSL_AD_ILLEGAL_PARAMETER; 1288 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_BAD_CHANGE_CIPHER_SPEC); 1289 goto f_err; 1290 } 1291 1292 /* Check we have a cipher to change to */ 1293 if (s->s3->tmp.new_cipher == NULL) 1294 { 1295 al=SSL_AD_UNEXPECTED_MESSAGE; 1296 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_CCS_RECEIVED_EARLY); 1297 goto f_err; 1298 } 1299 1300 rr->length=0; 1301 1302 if (s->msg_callback) 1303 s->msg_callback(0, s->version, SSL3_RT_CHANGE_CIPHER_SPEC, rr->data, 1, s, s->msg_callback_arg); 1304 1305 s->s3->change_cipher_spec=1; 1306 if (!ssl3_do_change_cipher_spec(s)) 1307 goto err; 1308 else 1309 goto start; 1310 } 1311 1312 /* Unexpected handshake message (Client Hello, or protocol violation) */ 1313 if ((s->s3->handshake_fragment_len >= 4) && !s->in_handshake) 1314 { 1315 if (((s->state&SSL_ST_MASK) == SSL_ST_OK) && 1316 !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS)) 1317 { 1318#if 0 /* worked only because C operator preferences are not as expected (and 1319 * because this is not really needed for clients except for detecting 1320 * protocol violations): */ 1321 s->state=SSL_ST_BEFORE|(s->server) 1322 ?SSL_ST_ACCEPT 1323 :SSL_ST_CONNECT; 1324#else 1325 s->state = s->server ? SSL_ST_ACCEPT : SSL_ST_CONNECT; 1326#endif 1327 s->renegotiate=1; 1328 s->new_session=1; 1329 } 1330 i=s->handshake_func(s); 1331 if (i < 0) return(i); 1332 if (i == 0) 1333 { 1334 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE); 1335 return(-1); 1336 } 1337 1338 if (!(s->mode & SSL_MODE_AUTO_RETRY)) 1339 { 1340 if (s->s3->rbuf.left == 0) /* no read-ahead left? */ 1341 { 1342 BIO *bio; 1343 /* In the case where we try to read application data, 1344 * but we trigger an SSL handshake, we return -1 with 1345 * the retry option set. Otherwise renegotiation may 1346 * cause nasty problems in the blocking world */ 1347 s->rwstate=SSL_READING; 1348 bio=SSL_get_rbio(s); 1349 BIO_clear_retry_flags(bio); 1350 BIO_set_retry_read(bio); 1351 return(-1); 1352 } 1353 } 1354 goto start; 1355 } 1356 1357 switch (rr->type) 1358 { 1359 default: 1360#ifndef OPENSSL_NO_TLS 1361 /* TLS up to v1.1 just ignores unknown message types: 1362 * TLS v1.2 give an unexpected message alert. 1363 */ 1364 if (s->version >= TLS1_VERSION && s->version <= TLS1_1_VERSION) 1365 { 1366 rr->length = 0; 1367 goto start; 1368 } 1369#endif 1370 al=SSL_AD_UNEXPECTED_MESSAGE; 1371 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNEXPECTED_RECORD); 1372 goto f_err; 1373 case SSL3_RT_CHANGE_CIPHER_SPEC: 1374 case SSL3_RT_ALERT: 1375 case SSL3_RT_HANDSHAKE: 1376 /* we already handled all of these, with the possible exception 1377 * of SSL3_RT_HANDSHAKE when s->in_handshake is set, but that 1378 * should not happen when type != rr->type */ 1379 al=SSL_AD_UNEXPECTED_MESSAGE; 1380 SSLerr(SSL_F_SSL3_READ_BYTES,ERR_R_INTERNAL_ERROR); 1381 goto f_err; 1382 case SSL3_RT_APPLICATION_DATA: 1383 /* At this point, we were expecting handshake data, 1384 * but have application data. If the library was 1385 * running inside ssl3_read() (i.e. in_read_app_data 1386 * is set) and it makes sense to read application data 1387 * at this point (session renegotiation not yet started), 1388 * we will indulge it. 1389 */ 1390 if (s->s3->in_read_app_data && 1391 (s->s3->total_renegotiations != 0) && 1392 (( 1393 (s->state & SSL_ST_CONNECT) && 1394 (s->state >= SSL3_ST_CW_CLNT_HELLO_A) && 1395 (s->state <= SSL3_ST_CR_SRVR_HELLO_A) 1396 ) || ( 1397 (s->state & SSL_ST_ACCEPT) && 1398 (s->state <= SSL3_ST_SW_HELLO_REQ_A) && 1399 (s->state >= SSL3_ST_SR_CLNT_HELLO_A) 1400 ) 1401 )) 1402 { 1403 s->s3->in_read_app_data=2; 1404 return(-1); 1405 } 1406 else 1407 { 1408 al=SSL_AD_UNEXPECTED_MESSAGE; 1409 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNEXPECTED_RECORD); 1410 goto f_err; 1411 } 1412 } 1413 /* not reached */ 1414 1415f_err: 1416 ssl3_send_alert(s,SSL3_AL_FATAL,al); 1417err: 1418 return(-1); 1419 } 1420 1421int ssl3_do_change_cipher_spec(SSL *s) 1422 { 1423 int i; 1424 const char *sender; 1425 int slen; 1426 1427 if (s->state & SSL_ST_ACCEPT) 1428 i=SSL3_CHANGE_CIPHER_SERVER_READ; 1429 else 1430 i=SSL3_CHANGE_CIPHER_CLIENT_READ; 1431 1432 if (s->s3->tmp.key_block == NULL) 1433 { 1434 if (s->session == NULL) 1435 { 1436 /* might happen if dtls1_read_bytes() calls this */ 1437 SSLerr(SSL_F_SSL3_DO_CHANGE_CIPHER_SPEC,SSL_R_CCS_RECEIVED_EARLY); 1438 return (0); 1439 } 1440 1441 s->session->cipher=s->s3->tmp.new_cipher; 1442 if (!s->method->ssl3_enc->setup_key_block(s)) return(0); 1443 } 1444 1445 if (!s->method->ssl3_enc->change_cipher_state(s,i)) 1446 return(0); 1447 1448 /* we have to record the message digest at 1449 * this point so we can get it before we read 1450 * the finished message */ 1451 if (s->state & SSL_ST_CONNECT) 1452 { 1453 sender=s->method->ssl3_enc->server_finished_label; 1454 slen=s->method->ssl3_enc->server_finished_label_len; 1455 } 1456 else 1457 { 1458 sender=s->method->ssl3_enc->client_finished_label; 1459 slen=s->method->ssl3_enc->client_finished_label_len; 1460 } 1461 1462 s->s3->tmp.peer_finish_md_len = s->method->ssl3_enc->final_finish_mac(s, 1463 sender,slen,s->s3->tmp.peer_finish_md); 1464 1465 return(1); 1466 } 1467 1468int ssl3_send_alert(SSL *s, int level, int desc) 1469 { 1470 /* Map tls/ssl alert value to correct one */ 1471 desc=s->method->ssl3_enc->alert_value(desc); 1472 if (s->version == SSL3_VERSION && desc == SSL_AD_PROTOCOL_VERSION) 1473 desc = SSL_AD_HANDSHAKE_FAILURE; /* SSL 3.0 does not have protocol_version alerts */ 1474 if (desc < 0) return -1; 1475 /* If a fatal one, remove from cache */ 1476 if ((level == 2) && (s->session != NULL)) 1477 SSL_CTX_remove_session(s->ctx,s->session); 1478 1479 s->s3->alert_dispatch=1; 1480 s->s3->send_alert[0]=level; 1481 s->s3->send_alert[1]=desc; 1482 if (s->s3->wbuf.left == 0) /* data still being written out? */ 1483 return s->method->ssl_dispatch_alert(s); 1484 /* else data is still being written out, we will get written 1485 * some time in the future */ 1486 return -1; 1487 } 1488 1489int ssl3_dispatch_alert(SSL *s) 1490 { 1491 int i,j; 1492 void (*cb)(const SSL *ssl,int type,int val)=NULL; 1493 1494 s->s3->alert_dispatch=0; 1495 i = do_ssl3_write(s, SSL3_RT_ALERT, &s->s3->send_alert[0], 2, 0); 1496 if (i <= 0) 1497 { 1498 s->s3->alert_dispatch=1; 1499 } 1500 else 1501 { 1502 /* Alert sent to BIO. If it is important, flush it now. 1503 * If the message does not get sent due to non-blocking IO, 1504 * we will not worry too much. */ 1505 if (s->s3->send_alert[0] == SSL3_AL_FATAL) 1506 (void)BIO_flush(s->wbio); 1507 1508 if (s->msg_callback) 1509 s->msg_callback(1, s->version, SSL3_RT_ALERT, s->s3->send_alert, 2, s, s->msg_callback_arg); 1510 1511 if (s->info_callback != NULL) 1512 cb=s->info_callback; 1513 else if (s->ctx->info_callback != NULL) 1514 cb=s->ctx->info_callback; 1515 1516 if (cb != NULL) 1517 { 1518 j=(s->s3->send_alert[0]<<8)|s->s3->send_alert[1]; 1519 cb(s,SSL_CB_WRITE_ALERT,j); 1520 } 1521 } 1522 return(i); 1523 } 1524