1 /* ssl/s3_pkt.c */ 2 /* Copyright (C) 1995-1998 Eric Young (eay (at) cryptsoft.com) 3 * All rights reserved. 4 * 5 * This package is an SSL implementation written 6 * by Eric Young (eay (at) 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 (at) 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 (at) 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 (at) 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 (at) 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 (at) cryptsoft.com). This product includes software written by Tim 108 * Hudson (tjh (at) cryptsoft.com). 109 * 110 */ 111 112 #include <stdio.h> 113 #include <limits.h> 114 #include <errno.h> 115 #define USE_SOCKETS 116 #include "ssl_locl.h" 117 #include <openssl/evp.h> 118 #include <openssl/buffer.h> 119 #include <openssl/rand.h> 120 121 static int do_ssl3_write(SSL *s, int type, const unsigned char *buf, 122 unsigned int len, char fragment, char is_fragment); 123 static int ssl3_get_record(SSL *s); 124 125 int ssl3_read_n(SSL *s, int n, int max, int extend) 126 { 127 /* If extend == 0, obtain new n-byte packet; if extend == 1, increase 128 * packet by another n bytes. 129 * The packet will be in the sub-array of s->s3->rbuf.buf specified 130 * by s->packet and s->packet_length. 131 * (If s->read_ahead is set, 'max' bytes may be stored in rbuf 132 * [plus s->packet_length bytes if extend == 1].) 133 */ 134 int i,len,left; 135 long align=0; 136 unsigned char *pkt; 137 SSL3_BUFFER *rb; 138 139 if (n <= 0) return n; 140 141 rb = &(s->s3->rbuf); 142 if (rb->buf == NULL) 143 if (!ssl3_setup_read_buffer(s)) 144 return -1; 145 146 left = rb->left; 147 #if defined(SSL3_ALIGN_PAYLOAD) && SSL3_ALIGN_PAYLOAD!=0 148 align = (long)rb->buf + SSL3_RT_HEADER_LENGTH; 149 align = (-align)&(SSL3_ALIGN_PAYLOAD-1); 150 #endif 151 152 if (!extend) 153 { 154 /* start with empty packet ... */ 155 if (left == 0) 156 rb->offset = align; 157 else if (align != 0 && left >= SSL3_RT_HEADER_LENGTH) 158 { 159 /* check if next packet length is large 160 * enough to justify payload alignment... */ 161 pkt = rb->buf + rb->offset; 162 if (pkt[0] == SSL3_RT_APPLICATION_DATA 163 && (pkt[3]<<8|pkt[4]) >= 128) 164 { 165 /* Note that even if packet is corrupted 166 * and its length field is insane, we can 167 * only be led to wrong decision about 168 * whether memmove will occur or not. 169 * Header values has no effect on memmove 170 * arguments and therefore no buffer 171 * overrun can be triggered. */ 172 memmove (rb->buf+align,pkt,left); 173 rb->offset = align; 174 } 175 } 176 s->packet = rb->buf + rb->offset; 177 s->packet_length = 0; 178 /* ... now we can act as if 'extend' was set */ 179 } 180 181 /* For DTLS/UDP reads should not span multiple packets 182 * because the read operation returns the whole packet 183 * at once (as long as it fits into the buffer). */ 184 if (SSL_version(s) == DTLS1_VERSION || SSL_version(s) == DTLS1_BAD_VER) 185 { 186 if (left > 0 && n > left) 187 n = left; 188 } 189 190 /* if there is enough in the buffer from a previous read, take some */ 191 if (left >= n) 192 { 193 s->packet_length+=n; 194 rb->left=left-n; 195 rb->offset+=n; 196 return(n); 197 } 198 199 /* else we need to read more data */ 200 201 len = s->packet_length; 202 pkt = rb->buf+align; 203 /* Move any available bytes to front of buffer: 204 * 'len' bytes already pointed to by 'packet', 205 * 'left' extra ones at the end */ 206 if (s->packet != pkt) /* len > 0 */ 207 { 208 memmove(pkt, s->packet, len+left); 209 s->packet = pkt; 210 rb->offset = len + align; 211 } 212 213 if (n > (int)(rb->len - rb->offset)) /* does not happen */ 214 { 215 SSLerr(SSL_F_SSL3_READ_N,ERR_R_INTERNAL_ERROR); 216 return -1; 217 } 218 219 if (!s->read_ahead) 220 /* ignore max parameter */ 221 max = n; 222 else 223 { 224 if (max < n) 225 max = n; 226 if (max > (int)(rb->len - rb->offset)) 227 max = rb->len - rb->offset; 228 } 229 230 while (left < n) 231 { 232 /* Now we have len+left bytes at the front of s->s3->rbuf.buf 233 * and need to read in more until we have len+n (up to 234 * len+max if possible) */ 235 236 clear_sys_error(); 237 if (s->rbio != NULL) 238 { 239 s->rwstate=SSL_READING; 240 i=BIO_read(s->rbio,pkt+len+left, max-left); 241 } 242 else 243 { 244 SSLerr(SSL_F_SSL3_READ_N,SSL_R_READ_BIO_NOT_SET); 245 i = -1; 246 } 247 248 if (i <= 0) 249 { 250 rb->left = left; 251 if (s->mode & SSL_MODE_RELEASE_BUFFERS && 252 SSL_version(s) != DTLS1_VERSION && SSL_version(s) != DTLS1_BAD_VER) 253 if (len+left == 0) 254 ssl3_release_read_buffer(s); 255 return(i); 256 } 257 left+=i; 258 /* reads should *never* span multiple packets for DTLS because 259 * the underlying transport protocol is message oriented as opposed 260 * to byte oriented as in the TLS case. */ 261 if (SSL_version(s) == DTLS1_VERSION || SSL_version(s) == DTLS1_BAD_VER) 262 { 263 if (n > left) 264 n = left; /* makes the while condition false */ 265 } 266 } 267 268 /* done reading, now the book-keeping */ 269 rb->offset += n; 270 rb->left = left - n; 271 s->packet_length += n; 272 s->rwstate=SSL_NOTHING; 273 return(n); 274 } 275 276 /* MAX_EMPTY_RECORDS defines the number of consecutive, empty records that will 277 * be processed per call to ssl3_get_record. Without this limit an attacker 278 * could send empty records at a faster rate than we can process and cause 279 * ssl3_get_record to loop forever. */ 280 #define MAX_EMPTY_RECORDS 32 281 282 /* Call this to get a new input record. 283 * It will return <= 0 if more data is needed, normally due to an error 284 * or non-blocking IO. 285 * When it finishes, one packet has been decoded and can be found in 286 * ssl->s3->rrec.type - is the type of record 287 * ssl->s3->rrec.data, - data 288 * ssl->s3->rrec.length, - number of bytes 289 */ 290 /* used only by ssl3_read_bytes */ 291 static int ssl3_get_record(SSL *s) 292 { 293 int ssl_major,ssl_minor,al; 294 int enc_err,n,i,ret= -1; 295 SSL3_RECORD *rr; 296 SSL_SESSION *sess; 297 unsigned char *p; 298 unsigned char md[EVP_MAX_MD_SIZE]; 299 short version; 300 unsigned mac_size, orig_len; 301 size_t extra; 302 unsigned empty_record_count = 0; 303 304 rr= &(s->s3->rrec); 305 sess=s->session; 306 307 if (s->options & SSL_OP_MICROSOFT_BIG_SSLV3_BUFFER) 308 extra=SSL3_RT_MAX_EXTRA; 309 else 310 extra=0; 311 if (extra && !s->s3->init_extra) 312 { 313 /* An application error: SLS_OP_MICROSOFT_BIG_SSLV3_BUFFER 314 * set after ssl3_setup_buffers() was done */ 315 SSLerr(SSL_F_SSL3_GET_RECORD, ERR_R_INTERNAL_ERROR); 316 return -1; 317 } 318 319 again: 320 /* check if we have the header */ 321 if ( (s->rstate != SSL_ST_READ_BODY) || 322 (s->packet_length < SSL3_RT_HEADER_LENGTH)) 323 { 324 n=ssl3_read_n(s, SSL3_RT_HEADER_LENGTH, s->s3->rbuf.len, 0); 325 if (n <= 0) return(n); /* error or non-blocking */ 326 s->rstate=SSL_ST_READ_BODY; 327 328 p=s->packet; 329 330 /* Pull apart the header into the SSL3_RECORD */ 331 rr->type= *(p++); 332 ssl_major= *(p++); 333 ssl_minor= *(p++); 334 version=(ssl_major<<8)|ssl_minor; 335 n2s(p,rr->length); 336 #if 0 337 fprintf(stderr, "Record type=%d, Length=%d\n", rr->type, rr->length); 338 #endif 339 340 /* Lets check version */ 341 if (!s->first_packet) 342 { 343 if (version != s->version) 344 { 345 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_WRONG_VERSION_NUMBER); 346 if ((s->version & 0xFF00) == (version & 0xFF00) && !s->enc_write_ctx && !s->write_hash) 347 /* Send back error using their minor version number :-) */ 348 s->version = (unsigned short)version; 349 al=SSL_AD_PROTOCOL_VERSION; 350 goto f_err; 351 } 352 } 353 354 if ((version>>8) != SSL3_VERSION_MAJOR) 355 { 356 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_WRONG_VERSION_NUMBER); 357 goto err; 358 } 359 360 if (rr->length > s->s3->rbuf.len - SSL3_RT_HEADER_LENGTH) 361 { 362 al=SSL_AD_RECORD_OVERFLOW; 363 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_PACKET_LENGTH_TOO_LONG); 364 goto f_err; 365 } 366 367 /* now s->rstate == SSL_ST_READ_BODY */ 368 } 369 370 /* s->rstate == SSL_ST_READ_BODY, get and decode the data */ 371 372 if (rr->length > s->packet_length-SSL3_RT_HEADER_LENGTH) 373 { 374 /* now s->packet_length == SSL3_RT_HEADER_LENGTH */ 375 i=rr->length; 376 n=ssl3_read_n(s,i,i,1); 377 if (n <= 0) return(n); /* error or non-blocking io */ 378 /* now n == rr->length, 379 * and s->packet_length == SSL3_RT_HEADER_LENGTH + rr->length */ 380 } 381 382 s->rstate=SSL_ST_READ_HEADER; /* set state for later operations */ 383 384 /* At this point, s->packet_length == SSL3_RT_HEADER_LNGTH + rr->length, 385 * and we have that many bytes in s->packet 386 */ 387 rr->input= &(s->packet[SSL3_RT_HEADER_LENGTH]); 388 389 /* ok, we can now read from 's->packet' data into 'rr' 390 * rr->input points at rr->length bytes, which 391 * need to be copied into rr->data by either 392 * the decryption or by the decompression 393 * When the data is 'copied' into the rr->data buffer, 394 * rr->input will be pointed at the new buffer */ 395 396 /* We now have - encrypted [ MAC [ compressed [ plain ] ] ] 397 * rr->length bytes of encrypted compressed stuff. */ 398 399 /* check is not needed I believe */ 400 if (rr->length > SSL3_RT_MAX_ENCRYPTED_LENGTH+extra) 401 { 402 al=SSL_AD_RECORD_OVERFLOW; 403 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_ENCRYPTED_LENGTH_TOO_LONG); 404 goto f_err; 405 } 406 407 /* decrypt in place in 'rr->input' */ 408 rr->data=rr->input; 409 410 enc_err = s->method->ssl3_enc->enc(s,0); 411 /* enc_err is: 412 * 0: (in non-constant time) if the record is publically invalid. 413 * 1: if the padding is valid 414 * -1: if the padding is invalid */ 415 if (enc_err == 0) 416 { 417 al=SSL_AD_DECRYPTION_FAILED; 418 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_BLOCK_CIPHER_PAD_IS_WRONG); 419 goto f_err; 420 } 421 422 #ifdef TLS_DEBUG 423 printf("dec %d\n",rr->length); 424 { unsigned int z; for (z=0; z<rr->length; z++) printf("%02X%c",rr->data[z],((z+1)%16)?' ':'\n'); } 425 printf("\n"); 426 #endif 427 428 /* r->length is now the compressed data plus mac */ 429 if ((sess != NULL) && 430 (s->enc_read_ctx != NULL) && 431 (EVP_MD_CTX_md(s->read_hash) != NULL)) 432 { 433 /* s->read_hash != NULL => mac_size != -1 */ 434 unsigned char *mac = NULL; 435 unsigned char mac_tmp[EVP_MAX_MD_SIZE]; 436 mac_size=EVP_MD_CTX_size(s->read_hash); 437 OPENSSL_assert(mac_size <= EVP_MAX_MD_SIZE); 438 439 /* kludge: *_cbc_remove_padding passes padding length in rr->type */ 440 orig_len = rr->length+((unsigned int)rr->type>>8); 441 442 /* orig_len is the length of the record before any padding was 443 * removed. This is public information, as is the MAC in use, 444 * therefore we can safely process the record in a different 445 * amount of time if it's too short to possibly contain a MAC. 446 */ 447 if (orig_len < mac_size || 448 /* CBC records must have a padding length byte too. */ 449 (EVP_CIPHER_CTX_mode(s->enc_read_ctx) == EVP_CIPH_CBC_MODE && 450 orig_len < mac_size+1)) 451 { 452 al=SSL_AD_DECODE_ERROR; 453 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_LENGTH_TOO_SHORT); 454 goto f_err; 455 } 456 457 if (EVP_CIPHER_CTX_mode(s->enc_read_ctx) == EVP_CIPH_CBC_MODE) 458 { 459 /* We update the length so that the TLS header bytes 460 * can be constructed correctly but we need to extract 461 * the MAC in constant time from within the record, 462 * without leaking the contents of the padding bytes. 463 * */ 464 mac = mac_tmp; 465 ssl3_cbc_copy_mac(mac_tmp, rr, mac_size, orig_len); 466 rr->length -= mac_size; 467 } 468 else 469 { 470 /* In this case there's no padding, so |orig_len| 471 * equals |rec->length| and we checked that there's 472 * enough bytes for |mac_size| above. */ 473 rr->length -= mac_size; 474 mac = &rr->data[rr->length]; 475 } 476 477 i=s->method->ssl3_enc->mac(s,md,0 /* not send */); 478 if (i < 0 || mac == NULL || CRYPTO_memcmp(md, mac, (size_t)mac_size) != 0) 479 enc_err = -1; 480 if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH+extra+mac_size) 481 enc_err = -1; 482 } 483 484 if (enc_err < 0) 485 { 486 /* A separate 'decryption_failed' alert was introduced with TLS 1.0, 487 * SSL 3.0 only has 'bad_record_mac'. But unless a decryption 488 * failure is directly visible from the ciphertext anyway, 489 * we should not reveal which kind of error occured -- this 490 * might become visible to an attacker (e.g. via a logfile) */ 491 al=SSL_AD_BAD_RECORD_MAC; 492 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_DECRYPTION_FAILED_OR_BAD_RECORD_MAC); 493 goto f_err; 494 } 495 496 /* r->length is now just compressed */ 497 if (s->expand != NULL) 498 { 499 if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH+extra) 500 { 501 al=SSL_AD_RECORD_OVERFLOW; 502 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_COMPRESSED_LENGTH_TOO_LONG); 503 goto f_err; 504 } 505 if (!ssl3_do_uncompress(s)) 506 { 507 al=SSL_AD_DECOMPRESSION_FAILURE; 508 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_BAD_DECOMPRESSION); 509 goto f_err; 510 } 511 } 512 513 if (rr->length > SSL3_RT_MAX_PLAIN_LENGTH+extra) 514 { 515 al=SSL_AD_RECORD_OVERFLOW; 516 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_DATA_LENGTH_TOO_LONG); 517 goto f_err; 518 } 519 520 rr->off=0; 521 /* So at this point the following is true 522 * ssl->s3->rrec.type is the type of record 523 * ssl->s3->rrec.length == number of bytes in record 524 * ssl->s3->rrec.off == offset to first valid byte 525 * ssl->s3->rrec.data == where to take bytes from, increment 526 * after use :-). 527 */ 528 529 /* we have pulled in a full packet so zero things */ 530 s->packet_length=0; 531 532 /* just read a 0 length packet */ 533 if (rr->length == 0) 534 { 535 empty_record_count++; 536 if (empty_record_count > MAX_EMPTY_RECORDS) 537 { 538 al=SSL_AD_UNEXPECTED_MESSAGE; 539 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_RECORD_TOO_SMALL); 540 goto f_err; 541 } 542 goto again; 543 } 544 545 #if 0 546 fprintf(stderr, "Ultimate Record type=%d, Length=%d\n", rr->type, rr->length); 547 #endif 548 549 return(1); 550 551 f_err: 552 ssl3_send_alert(s,SSL3_AL_FATAL,al); 553 err: 554 return(ret); 555 } 556 557 int ssl3_do_uncompress(SSL *ssl) 558 { 559 #ifndef OPENSSL_NO_COMP 560 int i; 561 SSL3_RECORD *rr; 562 563 rr= &(ssl->s3->rrec); 564 i=COMP_expand_block(ssl->expand,rr->comp, 565 SSL3_RT_MAX_PLAIN_LENGTH,rr->data,(int)rr->length); 566 if (i < 0) 567 return(0); 568 else 569 rr->length=i; 570 rr->data=rr->comp; 571 #endif 572 return(1); 573 } 574 575 int ssl3_do_compress(SSL *ssl) 576 { 577 #ifndef OPENSSL_NO_COMP 578 int i; 579 SSL3_RECORD *wr; 580 581 wr= &(ssl->s3->wrec); 582 i=COMP_compress_block(ssl->compress,wr->data, 583 SSL3_RT_MAX_COMPRESSED_LENGTH, 584 wr->input,(int)wr->length); 585 if (i < 0) 586 return(0); 587 else 588 wr->length=i; 589 590 wr->input=wr->data; 591 #endif 592 return(1); 593 } 594 595 /* Call this to write data in records of type 'type' 596 * It will return <= 0 if not all data has been sent or non-blocking IO. 597 */ 598 int ssl3_write_bytes(SSL *s, int type, const void *buf_, int len) 599 { 600 const unsigned char *buf=buf_; 601 unsigned int n,nw; 602 int i,tot; 603 604 s->rwstate=SSL_NOTHING; 605 OPENSSL_assert(s->s3->wnum <= INT_MAX); 606 tot=s->s3->wnum; 607 s->s3->wnum=0; 608 609 if (SSL_in_init(s) && !s->in_handshake) 610 { 611 i=s->handshake_func(s); 612 if (i < 0) return(i); 613 if (i == 0) 614 { 615 SSLerr(SSL_F_SSL3_WRITE_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE); 616 return -1; 617 } 618 } 619 620 /* ensure that if we end up with a smaller value of data to write 621 * out than the the original len from a write which didn't complete 622 * for non-blocking I/O and also somehow ended up avoiding 623 * the check for this in ssl3_write_pending/SSL_R_BAD_WRITE_RETRY as 624 * it must never be possible to end up with (len-tot) as a large 625 * number that will then promptly send beyond the end of the users 626 * buffer ... so we trap and report the error in a way the user 627 * will notice 628 */ 629 if (len < tot) 630 { 631 SSLerr(SSL_F_SSL3_WRITE_BYTES,SSL_R_BAD_LENGTH); 632 return(-1); 633 } 634 635 636 n=(len-tot); 637 for (;;) 638 { 639 /* max contains the maximum number of bytes that we can put 640 * into a record. */ 641 unsigned max = s->max_send_fragment; 642 /* fragment is true if do_ssl3_write should send the first byte 643 * in its own record in order to randomise a CBC IV. */ 644 int fragment = 0; 645 646 if (n > 1 && 647 s->s3->need_record_splitting && 648 type == SSL3_RT_APPLICATION_DATA && 649 !s->s3->record_split_done) 650 { 651 fragment = 1; 652 /* record_split_done records that the splitting has 653 * been done in case we hit an SSL_WANT_WRITE condition. 654 * In that case, we don't need to do the split again. */ 655 s->s3->record_split_done = 1; 656 } 657 658 if (n > max) 659 nw=max; 660 else 661 nw=n; 662 663 i=do_ssl3_write(s, type, &(buf[tot]), nw, fragment, 0); 664 if (i <= 0) 665 { 666 s->s3->wnum=tot; 667 /* Try to write the fragment next time. */ 668 s->s3->record_split_done = 0; 669 return i; 670 } 671 672 if ((i == (int)n) || 673 (type == SSL3_RT_APPLICATION_DATA && 674 (s->mode & SSL_MODE_ENABLE_PARTIAL_WRITE))) 675 { 676 /* next chunk of data should get another prepended, 677 * one-byte fragment in ciphersuites with known-IV 678 * weakness. */ 679 s->s3->record_split_done = 0; 680 return tot+i; 681 } 682 683 n-=i; 684 tot+=i; 685 } 686 } 687 688 /* do_ssl3_write writes an SSL record of the given type. If |fragment| is 1 689 * then it splits the record into a one byte record and a record with the rest 690 * of the data in order to randomise a CBC IV. If |is_fragment| is true then 691 * this call resulted from do_ssl3_write calling itself in order to create that 692 * one byte fragment. */ 693 static int do_ssl3_write(SSL *s, int type, const unsigned char *buf, 694 unsigned int len, char fragment, char is_fragment) 695 { 696 unsigned char *p,*plen; 697 int i,mac_size; 698 int prefix_len=0; 699 int eivlen; 700 long align=0; 701 SSL3_RECORD *wr; 702 SSL3_BUFFER *wb=&(s->s3->wbuf); 703 SSL_SESSION *sess; 704 705 706 /* first check if there is a SSL3_BUFFER still being written 707 * out. This will happen with non blocking IO */ 708 if (wb->left != 0) 709 return(ssl3_write_pending(s,type,buf,len)); 710 711 /* If we have an alert to send, lets send it */ 712 if (s->s3->alert_dispatch) 713 { 714 i=s->method->ssl_dispatch_alert(s); 715 if (i <= 0) 716 return(i); 717 /* if it went, fall through and send more stuff */ 718 } 719 720 if (wb->buf == NULL) 721 if (!ssl3_setup_write_buffer(s)) 722 return -1; 723 724 if (len == 0) 725 return 0; 726 727 wr= &(s->s3->wrec); 728 sess=s->session; 729 730 if ( (sess == NULL) || 731 (s->enc_write_ctx == NULL) || 732 (EVP_MD_CTX_md(s->write_hash) == NULL)) 733 { 734 mac_size=0; 735 } 736 else 737 { 738 mac_size=EVP_MD_CTX_size(s->write_hash); 739 if (mac_size < 0) 740 goto err; 741 } 742 743 if (fragment) 744 { 745 /* countermeasure against known-IV weakness in CBC ciphersuites 746 * (see http://www.openssl.org/~bodo/tls-cbc.txt) */ 747 prefix_len = do_ssl3_write(s, type, buf, 1 /* length */, 748 0 /* fragment */, 749 1 /* is_fragment */); 750 if (prefix_len <= 0) 751 goto err; 752 753 if (prefix_len > (SSL3_RT_HEADER_LENGTH + 754 SSL3_RT_SEND_MAX_ENCRYPTED_OVERHEAD)) 755 { 756 /* insufficient space */ 757 SSLerr(SSL_F_DO_SSL3_WRITE, ERR_R_INTERNAL_ERROR); 758 goto err; 759 } 760 } 761 762 if (is_fragment) 763 { 764 #if defined(SSL3_ALIGN_PAYLOAD) && SSL3_ALIGN_PAYLOAD!=0 765 /* The extra fragment would be couple of cipher blocks, and 766 * that will be a multiple of SSL3_ALIGN_PAYLOAD. So, if we 767 * want to align the real payload, we can just pretend that we 768 * have two headers and a byte. */ 769 align = (long)wb->buf + 2*SSL3_RT_HEADER_LENGTH + 1; 770 align = (-align)&(SSL3_ALIGN_PAYLOAD-1); 771 #endif 772 p = wb->buf + align; 773 wb->offset = align; 774 } 775 else if (prefix_len) 776 { 777 p = wb->buf + wb->offset + prefix_len; 778 } 779 else 780 { 781 #if defined(SSL3_ALIGN_PAYLOAD) && SSL3_ALIGN_PAYLOAD!=0 782 align = (long)wb->buf + SSL3_RT_HEADER_LENGTH; 783 align = (-align)&(SSL3_ALIGN_PAYLOAD-1); 784 #endif 785 p = wb->buf + align; 786 wb->offset = align; 787 } 788 789 /* write the header */ 790 791 *(p++)=type&0xff; 792 wr->type=type; 793 794 *(p++)=(s->version>>8); 795 /* Some servers hang if iniatial client hello is larger than 256 796 * bytes and record version number > TLS 1.0 797 */ 798 if (s->state == SSL3_ST_CW_CLNT_HELLO_B 799 && !s->renegotiate 800 && TLS1_get_version(s) > TLS1_VERSION) 801 *(p++) = 0x1; 802 else 803 *(p++)=s->version&0xff; 804 805 /* field where we are to write out packet length */ 806 plen=p; 807 p+=2; 808 /* Explicit IV length, block ciphers and TLS version 1.1 or later */ 809 if (s->enc_write_ctx && s->version >= TLS1_1_VERSION) 810 { 811 int mode = EVP_CIPHER_CTX_mode(s->enc_write_ctx); 812 if (mode == EVP_CIPH_CBC_MODE) 813 { 814 eivlen = EVP_CIPHER_CTX_iv_length(s->enc_write_ctx); 815 if (eivlen <= 1) 816 eivlen = 0; 817 } 818 /* Need explicit part of IV for GCM mode */ 819 else if (mode == EVP_CIPH_GCM_MODE) 820 eivlen = EVP_GCM_TLS_EXPLICIT_IV_LEN; 821 else 822 eivlen = 0; 823 } 824 else 825 eivlen = 0; 826 827 /* lets setup the record stuff. */ 828 wr->data=p + eivlen; 829 wr->length=(int)(len - (fragment != 0)); 830 wr->input=(unsigned char *)buf + (fragment != 0); 831 832 /* we now 'read' from wr->input, wr->length bytes into 833 * wr->data */ 834 835 /* first we compress */ 836 if (s->compress != NULL) 837 { 838 if (!ssl3_do_compress(s)) 839 { 840 SSLerr(SSL_F_DO_SSL3_WRITE,SSL_R_COMPRESSION_FAILURE); 841 goto err; 842 } 843 } 844 else 845 { 846 memcpy(wr->data,wr->input,wr->length); 847 wr->input=wr->data; 848 } 849 850 /* we should still have the output to wr->data and the input 851 * from wr->input. Length should be wr->length. 852 * wr->data still points in the wb->buf */ 853 854 if (mac_size != 0) 855 { 856 if (s->method->ssl3_enc->mac(s,&(p[wr->length + eivlen]),1) < 0) 857 goto err; 858 wr->length+=mac_size; 859 } 860 861 wr->input=p; 862 wr->data=p; 863 864 if (eivlen) 865 { 866 /* if (RAND_pseudo_bytes(p, eivlen) <= 0) 867 goto err; */ 868 wr->length += eivlen; 869 } 870 871 /* ssl3_enc can only have an error on read */ 872 s->method->ssl3_enc->enc(s,1); 873 874 /* record length after mac and block padding */ 875 s2n(wr->length,plen); 876 877 /* we should now have 878 * wr->data pointing to the encrypted data, which is 879 * wr->length long */ 880 wr->type=type; /* not needed but helps for debugging */ 881 wr->length+=SSL3_RT_HEADER_LENGTH; 882 883 if (is_fragment) 884 { 885 /* we are in a recursive call; just return the length, don't 886 * write out anything. */ 887 return wr->length; 888 } 889 890 /* now let's set up wb */ 891 wb->left = prefix_len + wr->length; 892 893 /* memorize arguments so that ssl3_write_pending can detect bad write retries later */ 894 s->s3->wpend_tot=len; 895 s->s3->wpend_buf=buf; 896 s->s3->wpend_type=type; 897 s->s3->wpend_ret=len; 898 899 /* we now just need to write the buffer */ 900 return ssl3_write_pending(s,type,buf,len); 901 err: 902 return -1; 903 } 904 905 /* if s->s3->wbuf.left != 0, we need to call this */ 906 int ssl3_write_pending(SSL *s, int type, const unsigned char *buf, 907 unsigned int len) 908 { 909 int i; 910 SSL3_BUFFER *wb=&(s->s3->wbuf); 911 912 /* XXXX */ 913 if ((s->s3->wpend_tot > (int)len) 914 || ((s->s3->wpend_buf != buf) && 915 !(s->mode & SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER)) 916 || (s->s3->wpend_type != type)) 917 { 918 SSLerr(SSL_F_SSL3_WRITE_PENDING,SSL_R_BAD_WRITE_RETRY); 919 return(-1); 920 } 921 922 for (;;) 923 { 924 clear_sys_error(); 925 if (s->wbio != NULL) 926 { 927 s->rwstate=SSL_WRITING; 928 i=BIO_write(s->wbio, 929 (char *)&(wb->buf[wb->offset]), 930 (unsigned int)wb->left); 931 } 932 else 933 { 934 SSLerr(SSL_F_SSL3_WRITE_PENDING,SSL_R_BIO_NOT_SET); 935 i= -1; 936 } 937 if (i == wb->left) 938 { 939 wb->left=0; 940 wb->offset+=i; 941 if (s->mode & SSL_MODE_RELEASE_BUFFERS && 942 SSL_version(s) != DTLS1_VERSION && SSL_version(s) != DTLS1_BAD_VER) 943 ssl3_release_write_buffer(s); 944 s->rwstate=SSL_NOTHING; 945 return(s->s3->wpend_ret); 946 } 947 else if (i <= 0) { 948 if (s->version == DTLS1_VERSION || 949 s->version == DTLS1_BAD_VER) { 950 /* For DTLS, just drop it. That's kind of the whole 951 point in using a datagram service */ 952 wb->left = 0; 953 } 954 return(i); 955 } 956 wb->offset+=i; 957 wb->left-=i; 958 } 959 } 960 961 /* Return up to 'len' payload bytes received in 'type' records. 962 * 'type' is one of the following: 963 * 964 * - SSL3_RT_HANDSHAKE (when ssl3_get_message calls us) 965 * - SSL3_RT_APPLICATION_DATA (when ssl3_read calls us) 966 * - 0 (during a shutdown, no data has to be returned) 967 * 968 * If we don't have stored data to work from, read a SSL/TLS record first 969 * (possibly multiple records if we still don't have anything to return). 970 * 971 * This function must handle any surprises the peer may have for us, such as 972 * Alert records (e.g. close_notify), ChangeCipherSpec records (not really 973 * a surprise, but handled as if it were), or renegotiation requests. 974 * Also if record payloads contain fragments too small to process, we store 975 * them until there is enough for the respective protocol (the record protocol 976 * may use arbitrary fragmentation and even interleaving): 977 * Change cipher spec protocol 978 * just 1 byte needed, no need for keeping anything stored 979 * Alert protocol 980 * 2 bytes needed (AlertLevel, AlertDescription) 981 * Handshake protocol 982 * 4 bytes needed (HandshakeType, uint24 length) -- we just have 983 * to detect unexpected Client Hello and Hello Request messages 984 * here, anything else is handled by higher layers 985 * Application data protocol 986 * none of our business 987 */ 988 int ssl3_read_bytes(SSL *s, int type, unsigned char *buf, int len, int peek) 989 { 990 int al,i,j,ret; 991 unsigned int n; 992 SSL3_RECORD *rr; 993 void (*cb)(const SSL *ssl,int type2,int val)=NULL; 994 995 if (s->s3->rbuf.buf == NULL) /* Not initialized yet */ 996 if (!ssl3_setup_read_buffer(s)) 997 return(-1); 998 999 if ((type && (type != SSL3_RT_APPLICATION_DATA) && (type != SSL3_RT_HANDSHAKE)) || 1000 (peek && (type != SSL3_RT_APPLICATION_DATA))) 1001 { 1002 SSLerr(SSL_F_SSL3_READ_BYTES, ERR_R_INTERNAL_ERROR); 1003 return -1; 1004 } 1005 1006 if ((type == SSL3_RT_HANDSHAKE) && (s->s3->handshake_fragment_len > 0)) 1007 /* (partially) satisfy request from storage */ 1008 { 1009 unsigned char *src = s->s3->handshake_fragment; 1010 unsigned char *dst = buf; 1011 unsigned int k; 1012 1013 /* peek == 0 */ 1014 n = 0; 1015 while ((len > 0) && (s->s3->handshake_fragment_len > 0)) 1016 { 1017 *dst++ = *src++; 1018 len--; s->s3->handshake_fragment_len--; 1019 n++; 1020 } 1021 /* move any remaining fragment bytes: */ 1022 for (k = 0; k < s->s3->handshake_fragment_len; k++) 1023 s->s3->handshake_fragment[k] = *src++; 1024 return n; 1025 } 1026 1027 /* Now s->s3->handshake_fragment_len == 0 if type == SSL3_RT_HANDSHAKE. */ 1028 1029 if (!s->in_handshake && SSL_in_init(s)) 1030 { 1031 /* type == SSL3_RT_APPLICATION_DATA */ 1032 i=s->handshake_func(s); 1033 if (i < 0) return(i); 1034 if (i == 0) 1035 { 1036 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE); 1037 return(-1); 1038 } 1039 } 1040 start: 1041 s->rwstate=SSL_NOTHING; 1042 1043 /* s->s3->rrec.type - is the type of record 1044 * s->s3->rrec.data, - data 1045 * s->s3->rrec.off, - offset into 'data' for next read 1046 * s->s3->rrec.length, - number of bytes. */ 1047 rr = &(s->s3->rrec); 1048 1049 /* get new packet if necessary */ 1050 if ((rr->length == 0) || (s->rstate == SSL_ST_READ_BODY)) 1051 { 1052 ret=ssl3_get_record(s); 1053 if (ret <= 0) return(ret); 1054 } 1055 1056 /* we now have a packet which can be read and processed */ 1057 1058 if (s->s3->change_cipher_spec /* set when we receive ChangeCipherSpec, 1059 * reset by ssl3_get_finished */ 1060 && (rr->type != SSL3_RT_HANDSHAKE)) 1061 { 1062 al=SSL_AD_UNEXPECTED_MESSAGE; 1063 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_DATA_BETWEEN_CCS_AND_FINISHED); 1064 goto f_err; 1065 } 1066 1067 /* If the other end has shut down, throw anything we read away 1068 * (even in 'peek' mode) */ 1069 if (s->shutdown & SSL_RECEIVED_SHUTDOWN) 1070 { 1071 rr->length=0; 1072 s->rwstate=SSL_NOTHING; 1073 return(0); 1074 } 1075 1076 1077 if (type == rr->type) /* SSL3_RT_APPLICATION_DATA or SSL3_RT_HANDSHAKE */ 1078 { 1079 /* make sure that we are not getting application data when we 1080 * are doing a handshake for the first time */ 1081 if (SSL_in_init(s) && (type == SSL3_RT_APPLICATION_DATA) && 1082 (s->enc_read_ctx == NULL)) 1083 { 1084 al=SSL_AD_UNEXPECTED_MESSAGE; 1085 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_APP_DATA_IN_HANDSHAKE); 1086 goto f_err; 1087 } 1088 1089 if (len <= 0) return(len); 1090 1091 if ((unsigned int)len > rr->length) 1092 n = rr->length; 1093 else 1094 n = (unsigned int)len; 1095 1096 memcpy(buf,&(rr->data[rr->off]),n); 1097 if (!peek) 1098 { 1099 rr->length-=n; 1100 rr->off+=n; 1101 if (rr->length == 0) 1102 { 1103 s->rstate=SSL_ST_READ_HEADER; 1104 rr->off=0; 1105 if (s->mode & SSL_MODE_RELEASE_BUFFERS && s->s3->rbuf.left == 0) 1106 ssl3_release_read_buffer(s); 1107 } 1108 } 1109 return(n); 1110 } 1111 1112 1113 /* If we get here, then type != rr->type; if we have a handshake 1114 * message, then it was unexpected (Hello Request or Client Hello). */ 1115 1116 /* In case of record types for which we have 'fragment' storage, 1117 * fill that so that we can process the data at a fixed place. 1118 */ 1119 { 1120 unsigned int dest_maxlen = 0; 1121 unsigned char *dest = NULL; 1122 unsigned int *dest_len = NULL; 1123 1124 if (rr->type == SSL3_RT_HANDSHAKE) 1125 { 1126 dest_maxlen = sizeof s->s3->handshake_fragment; 1127 dest = s->s3->handshake_fragment; 1128 dest_len = &s->s3->handshake_fragment_len; 1129 } 1130 else if (rr->type == SSL3_RT_ALERT) 1131 { 1132 dest_maxlen = sizeof s->s3->alert_fragment; 1133 dest = s->s3->alert_fragment; 1134 dest_len = &s->s3->alert_fragment_len; 1135 } 1136 #ifndef OPENSSL_NO_HEARTBEATS 1137 else if (rr->type == TLS1_RT_HEARTBEAT) 1138 { 1139 tls1_process_heartbeat(s); 1140 1141 /* Exit and notify application to read again */ 1142 rr->length = 0; 1143 s->rwstate=SSL_READING; 1144 BIO_clear_retry_flags(SSL_get_rbio(s)); 1145 BIO_set_retry_read(SSL_get_rbio(s)); 1146 return(-1); 1147 } 1148 #endif 1149 1150 if (dest_maxlen > 0) 1151 { 1152 n = dest_maxlen - *dest_len; /* available space in 'dest' */ 1153 if (rr->length < n) 1154 n = rr->length; /* available bytes */ 1155 1156 /* now move 'n' bytes: */ 1157 while (n-- > 0) 1158 { 1159 dest[(*dest_len)++] = rr->data[rr->off++]; 1160 rr->length--; 1161 } 1162 1163 if (*dest_len < dest_maxlen) 1164 goto start; /* fragment was too small */ 1165 } 1166 } 1167 1168 /* s->s3->handshake_fragment_len == 4 iff rr->type == SSL3_RT_HANDSHAKE; 1169 * s->s3->alert_fragment_len == 2 iff rr->type == SSL3_RT_ALERT. 1170 * (Possibly rr is 'empty' now, i.e. rr->length may be 0.) */ 1171 1172 /* If we are a client, check for an incoming 'Hello Request': */ 1173 if ((!s->server) && 1174 (s->s3->handshake_fragment_len >= 4) && 1175 (s->s3->handshake_fragment[0] == SSL3_MT_HELLO_REQUEST) && 1176 (s->session != NULL) && (s->session->cipher != NULL)) 1177 { 1178 s->s3->handshake_fragment_len = 0; 1179 1180 if ((s->s3->handshake_fragment[1] != 0) || 1181 (s->s3->handshake_fragment[2] != 0) || 1182 (s->s3->handshake_fragment[3] != 0)) 1183 { 1184 al=SSL_AD_DECODE_ERROR; 1185 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_BAD_HELLO_REQUEST); 1186 goto f_err; 1187 } 1188 1189 if (s->msg_callback) 1190 s->msg_callback(0, s->version, SSL3_RT_HANDSHAKE, s->s3->handshake_fragment, 4, s, s->msg_callback_arg); 1191 1192 if (SSL_is_init_finished(s) && 1193 !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS) && 1194 !s->s3->renegotiate) 1195 { 1196 ssl3_renegotiate(s); 1197 if (ssl3_renegotiate_check(s)) 1198 { 1199 i=s->handshake_func(s); 1200 if (i < 0) return(i); 1201 if (i == 0) 1202 { 1203 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE); 1204 return(-1); 1205 } 1206 1207 if (!(s->mode & SSL_MODE_AUTO_RETRY)) 1208 { 1209 if (s->s3->rbuf.left == 0) /* no read-ahead left? */ 1210 { 1211 BIO *bio; 1212 /* In the case where we try to read application data, 1213 * but we trigger an SSL handshake, we return -1 with 1214 * the retry option set. Otherwise renegotiation may 1215 * cause nasty problems in the blocking world */ 1216 s->rwstate=SSL_READING; 1217 bio=SSL_get_rbio(s); 1218 BIO_clear_retry_flags(bio); 1219 BIO_set_retry_read(bio); 1220 return(-1); 1221 } 1222 } 1223 } 1224 } 1225 /* we either finished a handshake or ignored the request, 1226 * now try again to obtain the (application) data we were asked for */ 1227 goto start; 1228 } 1229 /* If we are a server and get a client hello when renegotiation isn't 1230 * allowed send back a no renegotiation alert and carry on. 1231 * WARNING: experimental code, needs reviewing (steve) 1232 */ 1233 if (s->server && 1234 SSL_is_init_finished(s) && 1235 !s->s3->send_connection_binding && 1236 (s->version > SSL3_VERSION) && 1237 (s->s3->handshake_fragment_len >= 4) && 1238 (s->s3->handshake_fragment[0] == SSL3_MT_CLIENT_HELLO) && 1239 (s->session != NULL) && (s->session->cipher != NULL) && 1240 !(s->ctx->options & SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION)) 1241 1242 { 1243 /*s->s3->handshake_fragment_len = 0;*/ 1244 rr->length = 0; 1245 ssl3_send_alert(s,SSL3_AL_WARNING, SSL_AD_NO_RENEGOTIATION); 1246 goto start; 1247 } 1248 if (s->s3->alert_fragment_len >= 2) 1249 { 1250 int alert_level = s->s3->alert_fragment[0]; 1251 int alert_descr = s->s3->alert_fragment[1]; 1252 1253 s->s3->alert_fragment_len = 0; 1254 1255 if (s->msg_callback) 1256 s->msg_callback(0, s->version, SSL3_RT_ALERT, s->s3->alert_fragment, 2, s, s->msg_callback_arg); 1257 1258 if (s->info_callback != NULL) 1259 cb=s->info_callback; 1260 else if (s->ctx->info_callback != NULL) 1261 cb=s->ctx->info_callback; 1262 1263 if (cb != NULL) 1264 { 1265 j = (alert_level << 8) | alert_descr; 1266 cb(s, SSL_CB_READ_ALERT, j); 1267 } 1268 1269 if (alert_level == 1) /* warning */ 1270 { 1271 s->s3->warn_alert = alert_descr; 1272 if (alert_descr == SSL_AD_CLOSE_NOTIFY) 1273 { 1274 s->shutdown |= SSL_RECEIVED_SHUTDOWN; 1275 return(0); 1276 } 1277 /* This is a warning but we receive it if we requested 1278 * renegotiation and the peer denied it. Terminate with 1279 * a fatal alert because if application tried to 1280 * renegotiatie it presumably had a good reason and 1281 * expects it to succeed. 1282 * 1283 * In future we might have a renegotiation where we 1284 * don't care if the peer refused it where we carry on. 1285 */ 1286 else if (alert_descr == SSL_AD_NO_RENEGOTIATION) 1287 { 1288 al = SSL_AD_HANDSHAKE_FAILURE; 1289 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_NO_RENEGOTIATION); 1290 goto f_err; 1291 } 1292 #ifdef SSL_AD_MISSING_SRP_USERNAME 1293 else if (alert_descr == SSL_AD_MISSING_SRP_USERNAME) 1294 return(0); 1295 #endif 1296 } 1297 else if (alert_level == 2) /* fatal */ 1298 { 1299 char tmp[16]; 1300 1301 s->rwstate=SSL_NOTHING; 1302 s->s3->fatal_alert = alert_descr; 1303 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_AD_REASON_OFFSET + alert_descr); 1304 BIO_snprintf(tmp,sizeof tmp,"%d",alert_descr); 1305 ERR_add_error_data(2,"SSL alert number ",tmp); 1306 s->shutdown|=SSL_RECEIVED_SHUTDOWN; 1307 SSL_CTX_remove_session(s->ctx,s->session); 1308 return(0); 1309 } 1310 else 1311 { 1312 al=SSL_AD_ILLEGAL_PARAMETER; 1313 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNKNOWN_ALERT_TYPE); 1314 goto f_err; 1315 } 1316 1317 goto start; 1318 } 1319 1320 if (s->shutdown & SSL_SENT_SHUTDOWN) /* but we have not received a shutdown */ 1321 { 1322 s->rwstate=SSL_NOTHING; 1323 rr->length=0; 1324 return(0); 1325 } 1326 1327 if (rr->type == SSL3_RT_CHANGE_CIPHER_SPEC) 1328 { 1329 /* 'Change Cipher Spec' is just a single byte, so we know 1330 * exactly what the record payload has to look like */ 1331 if ( (rr->length != 1) || (rr->off != 0) || 1332 (rr->data[0] != SSL3_MT_CCS)) 1333 { 1334 al=SSL_AD_ILLEGAL_PARAMETER; 1335 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_BAD_CHANGE_CIPHER_SPEC); 1336 goto f_err; 1337 } 1338 1339 /* Check we have a cipher to change to */ 1340 if (s->s3->tmp.new_cipher == NULL) 1341 { 1342 al=SSL_AD_UNEXPECTED_MESSAGE; 1343 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_CCS_RECEIVED_EARLY); 1344 goto f_err; 1345 } 1346 1347 if (!(s->s3->flags & SSL3_FLAGS_CCS_OK)) 1348 { 1349 al=SSL_AD_UNEXPECTED_MESSAGE; 1350 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_CCS_RECEIVED_EARLY); 1351 goto f_err; 1352 } 1353 1354 s->s3->flags &= ~SSL3_FLAGS_CCS_OK; 1355 1356 rr->length=0; 1357 1358 if (s->msg_callback) 1359 s->msg_callback(0, s->version, SSL3_RT_CHANGE_CIPHER_SPEC, rr->data, 1, s, s->msg_callback_arg); 1360 1361 s->s3->change_cipher_spec=1; 1362 if (!ssl3_do_change_cipher_spec(s)) 1363 goto err; 1364 else 1365 goto start; 1366 } 1367 1368 /* Unexpected handshake message (Client Hello, or protocol violation) */ 1369 if ((s->s3->handshake_fragment_len >= 4) && !s->in_handshake) 1370 { 1371 if (((s->state&SSL_ST_MASK) == SSL_ST_OK) && 1372 !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS)) 1373 { 1374 #if 0 /* worked only because C operator preferences are not as expected (and 1375 * because this is not really needed for clients except for detecting 1376 * protocol violations): */ 1377 s->state=SSL_ST_BEFORE|(s->server) 1378 ?SSL_ST_ACCEPT 1379 :SSL_ST_CONNECT; 1380 #else 1381 s->state = s->server ? SSL_ST_ACCEPT : SSL_ST_CONNECT; 1382 #endif 1383 s->renegotiate=1; 1384 s->new_session=1; 1385 } 1386 i=s->handshake_func(s); 1387 if (i < 0) return(i); 1388 if (i == 0) 1389 { 1390 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE); 1391 return(-1); 1392 } 1393 1394 if (!(s->mode & SSL_MODE_AUTO_RETRY)) 1395 { 1396 if (s->s3->rbuf.left == 0) /* no read-ahead left? */ 1397 { 1398 BIO *bio; 1399 /* In the case where we try to read application data, 1400 * but we trigger an SSL handshake, we return -1 with 1401 * the retry option set. Otherwise renegotiation may 1402 * cause nasty problems in the blocking world */ 1403 s->rwstate=SSL_READING; 1404 bio=SSL_get_rbio(s); 1405 BIO_clear_retry_flags(bio); 1406 BIO_set_retry_read(bio); 1407 return(-1); 1408 } 1409 } 1410 goto start; 1411 } 1412 1413 switch (rr->type) 1414 { 1415 default: 1416 #ifndef OPENSSL_NO_TLS 1417 /* TLS up to v1.1 just ignores unknown message types: 1418 * TLS v1.2 give an unexpected message alert. 1419 */ 1420 if (s->version >= TLS1_VERSION && s->version <= TLS1_1_VERSION) 1421 { 1422 rr->length = 0; 1423 goto start; 1424 } 1425 #endif 1426 al=SSL_AD_UNEXPECTED_MESSAGE; 1427 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNEXPECTED_RECORD); 1428 goto f_err; 1429 case SSL3_RT_CHANGE_CIPHER_SPEC: 1430 case SSL3_RT_ALERT: 1431 case SSL3_RT_HANDSHAKE: 1432 /* we already handled all of these, with the possible exception 1433 * of SSL3_RT_HANDSHAKE when s->in_handshake is set, but that 1434 * should not happen when type != rr->type */ 1435 al=SSL_AD_UNEXPECTED_MESSAGE; 1436 SSLerr(SSL_F_SSL3_READ_BYTES,ERR_R_INTERNAL_ERROR); 1437 goto f_err; 1438 case SSL3_RT_APPLICATION_DATA: 1439 /* At this point, we were expecting handshake data, 1440 * but have application data. If the library was 1441 * running inside ssl3_read() (i.e. in_read_app_data 1442 * is set) and it makes sense to read application data 1443 * at this point (session renegotiation not yet started), 1444 * we will indulge it. 1445 */ 1446 if (s->s3->in_read_app_data && 1447 (s->s3->total_renegotiations != 0) && 1448 (( 1449 (s->state & SSL_ST_CONNECT) && 1450 (s->state >= SSL3_ST_CW_CLNT_HELLO_A) && 1451 (s->state <= SSL3_ST_CR_SRVR_HELLO_A) 1452 ) || ( 1453 (s->state & SSL_ST_ACCEPT) && 1454 (s->state <= SSL3_ST_SW_HELLO_REQ_A) && 1455 (s->state >= SSL3_ST_SR_CLNT_HELLO_A) 1456 ) 1457 )) 1458 { 1459 s->s3->in_read_app_data=2; 1460 return(-1); 1461 } 1462 else 1463 { 1464 al=SSL_AD_UNEXPECTED_MESSAGE; 1465 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNEXPECTED_RECORD); 1466 goto f_err; 1467 } 1468 } 1469 /* not reached */ 1470 1471 f_err: 1472 ssl3_send_alert(s,SSL3_AL_FATAL,al); 1473 err: 1474 return(-1); 1475 } 1476 1477 int ssl3_do_change_cipher_spec(SSL *s) 1478 { 1479 int i; 1480 const char *sender; 1481 int slen; 1482 1483 if (s->state & SSL_ST_ACCEPT) 1484 i=SSL3_CHANGE_CIPHER_SERVER_READ; 1485 else 1486 i=SSL3_CHANGE_CIPHER_CLIENT_READ; 1487 1488 if (s->s3->tmp.key_block == NULL) 1489 { 1490 if (s->session == NULL || s->session->master_key_length == 0) 1491 { 1492 /* might happen if dtls1_read_bytes() calls this */ 1493 SSLerr(SSL_F_SSL3_DO_CHANGE_CIPHER_SPEC,SSL_R_CCS_RECEIVED_EARLY); 1494 return (0); 1495 } 1496 1497 s->session->cipher=s->s3->tmp.new_cipher; 1498 if (!s->method->ssl3_enc->setup_key_block(s)) return(0); 1499 } 1500 1501 if (!s->method->ssl3_enc->change_cipher_state(s,i)) 1502 return(0); 1503 1504 /* we have to record the message digest at 1505 * this point so we can get it before we read 1506 * the finished message */ 1507 if (s->state & SSL_ST_CONNECT) 1508 { 1509 sender=s->method->ssl3_enc->server_finished_label; 1510 slen=s->method->ssl3_enc->server_finished_label_len; 1511 } 1512 else 1513 { 1514 sender=s->method->ssl3_enc->client_finished_label; 1515 slen=s->method->ssl3_enc->client_finished_label_len; 1516 } 1517 1518 i = s->method->ssl3_enc->final_finish_mac(s, 1519 sender,slen,s->s3->tmp.peer_finish_md); 1520 if (i == 0) 1521 { 1522 SSLerr(SSL_F_SSL3_DO_CHANGE_CIPHER_SPEC, ERR_R_INTERNAL_ERROR); 1523 return 0; 1524 } 1525 s->s3->tmp.peer_finish_md_len = i; 1526 1527 return(1); 1528 } 1529 1530 int ssl3_send_alert(SSL *s, int level, int desc) 1531 { 1532 /* Map tls/ssl alert value to correct one */ 1533 desc=s->method->ssl3_enc->alert_value(desc); 1534 if (s->version == SSL3_VERSION && desc == SSL_AD_PROTOCOL_VERSION) 1535 desc = SSL_AD_HANDSHAKE_FAILURE; /* SSL 3.0 does not have protocol_version alerts */ 1536 if (desc < 0) return -1; 1537 /* If a fatal one, remove from cache */ 1538 if ((level == 2) && (s->session != NULL)) 1539 SSL_CTX_remove_session(s->ctx,s->session); 1540 1541 s->s3->alert_dispatch=1; 1542 s->s3->send_alert[0]=level; 1543 s->s3->send_alert[1]=desc; 1544 if (s->s3->wbuf.left == 0) /* data still being written out? */ 1545 return s->method->ssl_dispatch_alert(s); 1546 /* else data is still being written out, we will get written 1547 * some time in the future */ 1548 return -1; 1549 } 1550 1551 int ssl3_dispatch_alert(SSL *s) 1552 { 1553 int i,j; 1554 void (*cb)(const SSL *ssl,int type,int val)=NULL; 1555 1556 s->s3->alert_dispatch=0; 1557 i = do_ssl3_write(s, SSL3_RT_ALERT, &s->s3->send_alert[0], 2, 0, 0); 1558 if (i <= 0) 1559 { 1560 s->s3->alert_dispatch=1; 1561 } 1562 else 1563 { 1564 /* Alert sent to BIO. If it is important, flush it now. 1565 * If the message does not get sent due to non-blocking IO, 1566 * we will not worry too much. */ 1567 if (s->s3->send_alert[0] == SSL3_AL_FATAL) 1568 (void)BIO_flush(s->wbio); 1569 1570 if (s->msg_callback) 1571 s->msg_callback(1, s->version, SSL3_RT_ALERT, s->s3->send_alert, 2, s, s->msg_callback_arg); 1572 1573 if (s->info_callback != NULL) 1574 cb=s->info_callback; 1575 else if (s->ctx->info_callback != NULL) 1576 cb=s->ctx->info_callback; 1577 1578 if (cb != NULL) 1579 { 1580 j=(s->s3->send_alert[0]<<8)|s->s3->send_alert[1]; 1581 cb(s,SSL_CB_WRITE_ALERT,j); 1582 } 1583 } 1584 return(i); 1585 } 1586
