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 <errno.h> 114 #define USE_SOCKETS 115 #include "ssl_locl.h" 116 #include <openssl/evp.h> 117 #include <openssl/buffer.h> 118 119 static int do_ssl3_write(SSL *s, int type, const unsigned char *buf, 120 unsigned int len, int create_empty_fragment); 121 static int ssl3_get_record(SSL *s); 122 123 int ssl3_read_n(SSL *s, int n, int max, int extend) 124 { 125 /* If extend == 0, obtain new n-byte packet; if extend == 1, increase 126 * packet by another n bytes. 127 * The packet will be in the sub-array of s->s3->rbuf.buf specified 128 * by s->packet and s->packet_length. 129 * (If s->read_ahead is set, 'max' bytes may be stored in rbuf 130 * [plus s->packet_length bytes if extend == 1].) 131 */ 132 int i,len,left; 133 long align=0; 134 unsigned char *pkt; 135 SSL3_BUFFER *rb; 136 137 if (n <= 0) return n; 138 139 rb = &(s->s3->rbuf); 140 if (rb->buf == NULL) 141 if (!ssl3_setup_read_buffer(s)) 142 return -1; 143 144 left = rb->left; 145 #if defined(SSL3_ALIGN_PAYLOAD) && SSL3_ALIGN_PAYLOAD!=0 146 align = (long)rb->buf + SSL3_RT_HEADER_LENGTH; 147 align = (-align)&(SSL3_ALIGN_PAYLOAD-1); 148 #endif 149 150 if (!extend) 151 { 152 /* start with empty packet ... */ 153 if (left == 0) 154 rb->offset = align; 155 else if (align != 0 && left >= SSL3_RT_HEADER_LENGTH) 156 { 157 /* check if next packet length is large 158 * enough to justify payload alignment... */ 159 pkt = rb->buf + rb->offset; 160 if (pkt[0] == SSL3_RT_APPLICATION_DATA 161 && (pkt[3]<<8|pkt[4]) >= 128) 162 { 163 /* Note that even if packet is corrupted 164 * and its length field is insane, we can 165 * only be led to wrong decision about 166 * whether memmove will occur or not. 167 * Header values has no effect on memmove 168 * arguments and therefore no buffer 169 * overrun can be triggered. */ 170 memmove (rb->buf+align,pkt,left); 171 rb->offset = align; 172 } 173 } 174 s->packet = rb->buf + rb->offset; 175 s->packet_length = 0; 176 /* ... now we can act as if 'extend' was set */ 177 } 178 179 /* For DTLS/UDP reads should not span multiple packets 180 * because the read operation returns the whole packet 181 * at once (as long as it fits into the buffer). */ 182 if (SSL_version(s) == DTLS1_VERSION || SSL_version(s) == DTLS1_BAD_VER) 183 { 184 if (left > 0 && n > left) 185 n = left; 186 } 187 188 /* if there is enough in the buffer from a previous read, take some */ 189 if (left >= n) 190 { 191 s->packet_length+=n; 192 rb->left=left-n; 193 rb->offset+=n; 194 return(n); 195 } 196 197 /* else we need to read more data */ 198 199 len = s->packet_length; 200 pkt = rb->buf+align; 201 /* Move any available bytes to front of buffer: 202 * 'len' bytes already pointed to by 'packet', 203 * 'left' extra ones at the end */ 204 if (s->packet != pkt) /* len > 0 */ 205 { 206 memmove(pkt, s->packet, len+left); 207 s->packet = pkt; 208 rb->offset = len + align; 209 } 210 211 if (n > (int)(rb->len - rb->offset)) /* does not happen */ 212 { 213 SSLerr(SSL_F_SSL3_READ_N,ERR_R_INTERNAL_ERROR); 214 return -1; 215 } 216 217 if (!s->read_ahead) 218 /* ignore max parameter */ 219 max = n; 220 else 221 { 222 if (max < n) 223 max = n; 224 if (max > (int)(rb->len - rb->offset)) 225 max = rb->len - rb->offset; 226 } 227 228 while (left < n) 229 { 230 /* Now we have len+left bytes at the front of s->s3->rbuf.buf 231 * and need to read in more until we have len+n (up to 232 * len+max if possible) */ 233 234 clear_sys_error(); 235 if (s->rbio != NULL) 236 { 237 s->rwstate=SSL_READING; 238 i=BIO_read(s->rbio,pkt+len+left, max-left); 239 } 240 else 241 { 242 SSLerr(SSL_F_SSL3_READ_N,SSL_R_READ_BIO_NOT_SET); 243 i = -1; 244 } 245 246 if (i <= 0) 247 { 248 rb->left = left; 249 if (s->mode & SSL_MODE_RELEASE_BUFFERS) 250 if (len+left == 0) 251 ssl3_release_read_buffer(s); 252 return(i); 253 } 254 left+=i; 255 /* reads should *never* span multiple packets for DTLS because 256 * the underlying transport protocol is message oriented as opposed 257 * to byte oriented as in the TLS case. */ 258 if (SSL_version(s) == DTLS1_VERSION || SSL_version(s) == DTLS1_BAD_VER) 259 { 260 if (n > left) 261 n = left; /* makes the while condition false */ 262 } 263 } 264 265 /* done reading, now the book-keeping */ 266 rb->offset += n; 267 rb->left = left - n; 268 s->packet_length += n; 269 s->rwstate=SSL_NOTHING; 270 return(n); 271 } 272 273 /* Call this to get a new input record. 274 * It will return <= 0 if more data is needed, normally due to an error 275 * or non-blocking IO. 276 * When it finishes, one packet has been decoded and can be found in 277 * ssl->s3->rrec.type - is the type of record 278 * ssl->s3->rrec.data, - data 279 * ssl->s3->rrec.length, - number of bytes 280 */ 281 /* used only by ssl3_read_bytes */ 282 static int ssl3_get_record(SSL *s) 283 { 284 int ssl_major,ssl_minor,al; 285 int enc_err,n,i,ret= -1; 286 SSL3_RECORD *rr; 287 SSL_SESSION *sess; 288 unsigned char *p; 289 unsigned char md[EVP_MAX_MD_SIZE]; 290 short version; 291 int mac_size; 292 int clear=0; 293 size_t extra; 294 int decryption_failed_or_bad_record_mac = 0; 295 unsigned char *mac = NULL; 296 #if defined(SSL3_ALIGN_PAYLOAD) && SSL3_ALIGN_PAYLOAD!=0 297 long align=SSL3_ALIGN_PAYLOAD; 298 #else 299 long align=0; 300 #endif 301 302 rr= &(s->s3->rrec); 303 sess=s->session; 304 305 if (s->options & SSL_OP_MICROSOFT_BIG_SSLV3_BUFFER) 306 extra=SSL3_RT_MAX_EXTRA; 307 else 308 extra=0; 309 if (!(SSL_get_mode(s) & SSL_MODE_SMALL_BUFFERS) && 310 extra && !s->s3->init_extra) 311 { 312 /* An application error: SLS_OP_MICROSOFT_BIG_SSLV3_BUFFER 313 * set after ssl3_setup_buffers() was done */ 314 SSLerr(SSL_F_SSL3_GET_RECORD, ERR_R_INTERNAL_ERROR); 315 return -1; 316 } 317 318 again: 319 /* check if we have the header */ 320 if ( (s->rstate != SSL_ST_READ_BODY) || 321 (s->packet_length < SSL3_RT_HEADER_LENGTH)) 322 { 323 n=ssl3_read_n(s, SSL3_RT_HEADER_LENGTH, s->s3->rbuf.len, 0); 324 if (n <= 0) return(n); /* error or non-blocking */ 325 s->rstate=SSL_ST_READ_BODY; 326 327 p=s->packet; 328 329 /* Pull apart the header into the SSL3_RECORD */ 330 rr->type= *(p++); 331 ssl_major= *(p++); 332 ssl_minor= *(p++); 333 version=(ssl_major<<8)|ssl_minor; 334 n2s(p,rr->length); 335 #if 0 336 fprintf(stderr, "Record type=%d, Length=%d\n", rr->type, rr->length); 337 #endif 338 339 /* Lets check version */ 340 if (!s->first_packet) 341 { 342 if (version != s->version) 343 { 344 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_WRONG_VERSION_NUMBER); 345 if ((s->version & 0xFF00) == (version & 0xFF00)) 346 /* Send back error using their minor version number :-) */ 347 s->version = (unsigned short)version; 348 al=SSL_AD_PROTOCOL_VERSION; 349 goto f_err; 350 } 351 } 352 353 if ((version>>8) != SSL3_VERSION_MAJOR) 354 { 355 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_WRONG_VERSION_NUMBER); 356 goto err; 357 } 358 359 /* If we receive a valid record larger than the current buffer size, 360 * allocate some memory for it. 361 */ 362 if (rr->length > s->s3->rbuf.len - SSL3_RT_HEADER_LENGTH - align) 363 { 364 if ((p=OPENSSL_realloc(s->s3->rbuf.buf, rr->length + SSL3_RT_HEADER_LENGTH + align))==NULL) 365 { 366 SSLerr(SSL_F_SSL3_GET_RECORD,ERR_R_MALLOC_FAILURE); 367 goto err; 368 } 369 s->s3->rbuf.buf=p; 370 s->s3->rbuf.len=rr->length + SSL3_RT_HEADER_LENGTH + align; 371 s->packet= &(s->s3->rbuf.buf[0]); 372 } 373 374 if (rr->length > s->s3->rbuf.len - SSL3_RT_HEADER_LENGTH) 375 { 376 al=SSL_AD_RECORD_OVERFLOW; 377 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_PACKET_LENGTH_TOO_LONG); 378 goto f_err; 379 } 380 381 /* now s->rstate == SSL_ST_READ_BODY */ 382 } 383 384 /* s->rstate == SSL_ST_READ_BODY, get and decode the data */ 385 386 if (rr->length > s->packet_length-SSL3_RT_HEADER_LENGTH) 387 { 388 /* now s->packet_length == SSL3_RT_HEADER_LENGTH */ 389 i=rr->length; 390 n=ssl3_read_n(s,i,i,1); 391 if (n <= 0) return(n); /* error or non-blocking io */ 392 /* now n == rr->length, 393 * and s->packet_length == SSL3_RT_HEADER_LENGTH + rr->length */ 394 } 395 396 s->rstate=SSL_ST_READ_HEADER; /* set state for later operations */ 397 398 /* At this point, s->packet_length == SSL3_RT_HEADER_LNGTH + rr->length, 399 * and we have that many bytes in s->packet 400 */ 401 rr->input= &(s->packet[SSL3_RT_HEADER_LENGTH]); 402 403 /* ok, we can now read from 's->packet' data into 'rr' 404 * rr->input points at rr->length bytes, which 405 * need to be copied into rr->data by either 406 * the decryption or by the decompression 407 * When the data is 'copied' into the rr->data buffer, 408 * rr->input will be pointed at the new buffer */ 409 410 /* We now have - encrypted [ MAC [ compressed [ plain ] ] ] 411 * rr->length bytes of encrypted compressed stuff. */ 412 413 /* check is not needed I believe */ 414 if (rr->length > SSL3_RT_MAX_ENCRYPTED_LENGTH+extra) 415 { 416 al=SSL_AD_RECORD_OVERFLOW; 417 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_ENCRYPTED_LENGTH_TOO_LONG); 418 goto f_err; 419 } 420 421 /* decrypt in place in 'rr->input' */ 422 rr->data=rr->input; 423 424 enc_err = s->method->ssl3_enc->enc(s,0); 425 if (enc_err <= 0) 426 { 427 if (enc_err == 0) 428 /* SSLerr() and ssl3_send_alert() have been called */ 429 goto err; 430 431 /* Otherwise enc_err == -1, which indicates bad padding 432 * (rec->length has not been changed in this case). 433 * To minimize information leaked via timing, we will perform 434 * the MAC computation anyway. */ 435 decryption_failed_or_bad_record_mac = 1; 436 } 437 438 #ifdef TLS_DEBUG 439 printf("dec %d\n",rr->length); 440 { unsigned int z; for (z=0; z<rr->length; z++) printf("%02X%c",rr->data[z],((z+1)%16)?' ':'\n'); } 441 printf("\n"); 442 #endif 443 444 /* r->length is now the compressed data plus mac */ 445 if ( (sess == NULL) || 446 (s->enc_read_ctx == NULL) || 447 (EVP_MD_CTX_md(s->read_hash) == NULL)) 448 clear=1; 449 450 if (!clear) 451 { 452 /* !clear => s->read_hash != NULL => mac_size != -1 */ 453 mac_size=EVP_MD_CTX_size(s->read_hash); 454 OPENSSL_assert(mac_size >= 0); 455 456 if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH+extra+mac_size) 457 { 458 #if 0 /* OK only for stream ciphers (then rr->length is visible from ciphertext anyway) */ 459 al=SSL_AD_RECORD_OVERFLOW; 460 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_PRE_MAC_LENGTH_TOO_LONG); 461 goto f_err; 462 #else 463 decryption_failed_or_bad_record_mac = 1; 464 #endif 465 } 466 /* check the MAC for rr->input (it's in mac_size bytes at the tail) */ 467 if (rr->length >= (unsigned int)mac_size) 468 { 469 rr->length -= mac_size; 470 mac = &rr->data[rr->length]; 471 } 472 else 473 { 474 /* record (minus padding) is too short to contain a MAC */ 475 #if 0 /* OK only for stream ciphers */ 476 al=SSL_AD_DECODE_ERROR; 477 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_LENGTH_TOO_SHORT); 478 goto f_err; 479 #else 480 decryption_failed_or_bad_record_mac = 1; 481 rr->length = 0; 482 #endif 483 } 484 i=s->method->ssl3_enc->mac(s,md,0); 485 if (i < 0 || mac == NULL || memcmp(md, mac, (size_t)mac_size) != 0) 486 { 487 decryption_failed_or_bad_record_mac = 1; 488 } 489 } 490 491 if (decryption_failed_or_bad_record_mac) 492 { 493 /* A separate 'decryption_failed' alert was introduced with TLS 1.0, 494 * SSL 3.0 only has 'bad_record_mac'. But unless a decryption 495 * failure is directly visible from the ciphertext anyway, 496 * we should not reveal which kind of error occured -- this 497 * might become visible to an attacker (e.g. via a logfile) */ 498 al=SSL_AD_BAD_RECORD_MAC; 499 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_DECRYPTION_FAILED_OR_BAD_RECORD_MAC); 500 goto f_err; 501 } 502 503 /* r->length is now just compressed */ 504 if (s->expand != NULL) 505 { 506 if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH+extra) 507 { 508 al=SSL_AD_RECORD_OVERFLOW; 509 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_COMPRESSED_LENGTH_TOO_LONG); 510 goto f_err; 511 } 512 if (!ssl3_do_uncompress(s)) 513 { 514 al=SSL_AD_DECOMPRESSION_FAILURE; 515 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_BAD_DECOMPRESSION); 516 goto f_err; 517 } 518 } 519 520 if (rr->length > SSL3_RT_MAX_PLAIN_LENGTH+extra) 521 { 522 al=SSL_AD_RECORD_OVERFLOW; 523 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_DATA_LENGTH_TOO_LONG); 524 goto f_err; 525 } 526 527 rr->off=0; 528 /* So at this point the following is true 529 * ssl->s3->rrec.type is the type of record 530 * ssl->s3->rrec.length == number of bytes in record 531 * ssl->s3->rrec.off == offset to first valid byte 532 * ssl->s3->rrec.data == where to take bytes from, increment 533 * after use :-). 534 */ 535 536 /* we have pulled in a full packet so zero things */ 537 s->packet_length=0; 538 539 /* just read a 0 length packet */ 540 if (rr->length == 0) goto again; 541 542 #if 0 543 fprintf(stderr, "Ultimate Record type=%d, Length=%d\n", rr->type, rr->length); 544 #endif 545 546 return(1); 547 548 f_err: 549 ssl3_send_alert(s,SSL3_AL_FATAL,al); 550 err: 551 return(ret); 552 } 553 554 int ssl3_do_uncompress(SSL *ssl) 555 { 556 #ifndef OPENSSL_NO_COMP 557 int i; 558 SSL3_RECORD *rr; 559 560 rr= &(ssl->s3->rrec); 561 i=COMP_expand_block(ssl->expand,rr->comp, 562 SSL3_RT_MAX_PLAIN_LENGTH,rr->data,(int)rr->length); 563 if (i < 0) 564 return(0); 565 else 566 rr->length=i; 567 rr->data=rr->comp; 568 #endif 569 return(1); 570 } 571 572 int ssl3_do_compress(SSL *ssl) 573 { 574 #ifndef OPENSSL_NO_COMP 575 int i; 576 SSL3_RECORD *wr; 577 578 wr= &(ssl->s3->wrec); 579 i=COMP_compress_block(ssl->compress,wr->data, 580 SSL3_RT_MAX_COMPRESSED_LENGTH, 581 wr->input,(int)wr->length); 582 if (i < 0) 583 return(0); 584 else 585 wr->length=i; 586 587 wr->input=wr->data; 588 #endif 589 return(1); 590 } 591 592 /* Call this to write data in records of type 'type' 593 * It will return <= 0 if not all data has been sent or non-blocking IO. 594 */ 595 int ssl3_write_bytes(SSL *s, int type, const void *buf_, int len) 596 { 597 const unsigned char *buf=buf_; 598 unsigned int tot,n,nw; 599 int i; 600 unsigned int max_plain_length; 601 602 s->rwstate=SSL_NOTHING; 603 tot=s->s3->wnum; 604 s->s3->wnum=0; 605 606 if (SSL_in_init(s) && !s->in_handshake) 607 { 608 i=s->handshake_func(s); 609 if (i < 0) return(i); 610 if (i == 0) 611 { 612 SSLerr(SSL_F_SSL3_WRITE_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE); 613 return -1; 614 } 615 } 616 617 n=(len-tot); 618 for (;;) 619 { 620 if (type == SSL3_RT_APPLICATION_DATA && (SSL_get_mode(s) & SSL_MODE_SMALL_BUFFERS)) 621 max_plain_length = SSL3_RT_DEFAULT_PLAIN_LENGTH; 622 else 623 max_plain_length = s->max_send_fragment; 624 625 if (n > max_plain_length) 626 nw = max_plain_length; 627 else 628 nw=n; 629 630 i=do_ssl3_write(s, type, &(buf[tot]), nw, 0); 631 if (i <= 0) 632 { 633 s->s3->wnum=tot; 634 return i; 635 } 636 637 if ((i == (int)n) || 638 (type == SSL3_RT_APPLICATION_DATA && 639 (s->mode & SSL_MODE_ENABLE_PARTIAL_WRITE))) 640 { 641 /* next chunk of data should get another prepended empty fragment 642 * in ciphersuites with known-IV weakness: */ 643 s->s3->empty_fragment_done = 0; 644 645 return tot+i; 646 } 647 648 n-=i; 649 tot+=i; 650 } 651 } 652 653 static int do_ssl3_write(SSL *s, int type, const unsigned char *buf, 654 unsigned int len, int create_empty_fragment) 655 { 656 unsigned char *p,*plen; 657 int i,mac_size,clear=0; 658 int prefix_len=0; 659 long align=0; 660 SSL3_RECORD *wr; 661 SSL3_BUFFER *wb=&(s->s3->wbuf); 662 SSL_SESSION *sess; 663 664 if (wb->buf == NULL) 665 if (!ssl3_setup_write_buffer(s)) 666 return -1; 667 668 /* first check if there is a SSL3_BUFFER still being written 669 * out. This will happen with non blocking IO */ 670 if (wb->left != 0) 671 return(ssl3_write_pending(s,type,buf,len)); 672 673 /* If we have an alert to send, lets send it */ 674 if (s->s3->alert_dispatch) 675 { 676 i=s->method->ssl_dispatch_alert(s); 677 if (i <= 0) 678 return(i); 679 /* if it went, fall through and send more stuff */ 680 } 681 682 if (len == 0 && !create_empty_fragment) 683 return 0; 684 685 wr= &(s->s3->wrec); 686 sess=s->session; 687 688 if ( (sess == NULL) || 689 (s->enc_write_ctx == NULL) || 690 (EVP_MD_CTX_md(s->write_hash) == NULL)) 691 clear=1; 692 693 if (clear) 694 mac_size=0; 695 else 696 { 697 mac_size=EVP_MD_CTX_size(s->write_hash); 698 if (mac_size < 0) 699 goto err; 700 } 701 702 /* 'create_empty_fragment' is true only when this function calls itself */ 703 if (!clear && !create_empty_fragment && !s->s3->empty_fragment_done) 704 { 705 /* countermeasure against known-IV weakness in CBC ciphersuites 706 * (see http://www.openssl.org/~bodo/tls-cbc.txt) */ 707 708 if (s->s3->need_empty_fragments && type == SSL3_RT_APPLICATION_DATA) 709 { 710 /* recursive function call with 'create_empty_fragment' set; 711 * this prepares and buffers the data for an empty fragment 712 * (these 'prefix_len' bytes are sent out later 713 * together with the actual payload) */ 714 prefix_len = do_ssl3_write(s, type, buf, 0, 1); 715 if (prefix_len <= 0) 716 goto err; 717 718 if (prefix_len > 719 (SSL3_RT_HEADER_LENGTH + SSL3_RT_SEND_MAX_ENCRYPTED_OVERHEAD)) 720 { 721 /* insufficient space */ 722 SSLerr(SSL_F_DO_SSL3_WRITE, ERR_R_INTERNAL_ERROR); 723 goto err; 724 } 725 } 726 727 s->s3->empty_fragment_done = 1; 728 } 729 730 /* resize if necessary to hold the data. */ 731 if (len + SSL3_RT_DEFAULT_WRITE_OVERHEAD > wb->len) 732 { 733 if ((p=OPENSSL_realloc(wb->buf, len + SSL3_RT_DEFAULT_WRITE_OVERHEAD))==NULL) 734 { 735 SSLerr(SSL_F_DO_SSL3_WRITE,ERR_R_MALLOC_FAILURE); 736 goto err; 737 } 738 wb->buf = p; 739 wb->len = len + SSL3_RT_DEFAULT_WRITE_OVERHEAD; 740 } 741 742 if (create_empty_fragment) 743 { 744 #if defined(SSL3_ALIGN_PAYLOAD) && SSL3_ALIGN_PAYLOAD!=0 745 /* extra fragment would be couple of cipher blocks, 746 * which would be multiple of SSL3_ALIGN_PAYLOAD, so 747 * if we want to align the real payload, then we can 748 * just pretent we simply have two headers. */ 749 align = (long)wb->buf + 2*SSL3_RT_HEADER_LENGTH; 750 align = (-align)&(SSL3_ALIGN_PAYLOAD-1); 751 #endif 752 p = wb->buf + align; 753 wb->offset = align; 754 } 755 else if (prefix_len) 756 { 757 p = wb->buf + wb->offset + prefix_len; 758 } 759 else 760 { 761 #if defined(SSL3_ALIGN_PAYLOAD) && SSL3_ALIGN_PAYLOAD!=0 762 align = (long)wb->buf + SSL3_RT_HEADER_LENGTH; 763 align = (-align)&(SSL3_ALIGN_PAYLOAD-1); 764 #endif 765 p = wb->buf + align; 766 wb->offset = align; 767 } 768 769 /* write the header */ 770 771 *(p++)=type&0xff; 772 wr->type=type; 773 774 *(p++)=(s->version>>8); 775 *(p++)=s->version&0xff; 776 777 /* field where we are to write out packet length */ 778 plen=p; 779 p+=2; 780 781 /* lets setup the record stuff. */ 782 wr->data=p; 783 wr->length=(int)len; 784 wr->input=(unsigned char *)buf; 785 786 /* we now 'read' from wr->input, wr->length bytes into 787 * wr->data */ 788 789 /* first we compress */ 790 if (s->compress != NULL) 791 { 792 if (!ssl3_do_compress(s)) 793 { 794 SSLerr(SSL_F_DO_SSL3_WRITE,SSL_R_COMPRESSION_FAILURE); 795 goto err; 796 } 797 } 798 else 799 { 800 memcpy(wr->data,wr->input,wr->length); 801 wr->input=wr->data; 802 } 803 804 /* we should still have the output to wr->data and the input 805 * from wr->input. Length should be wr->length. 806 * wr->data still points in the wb->buf */ 807 808 if (mac_size != 0) 809 { 810 if (s->method->ssl3_enc->mac(s,&(p[wr->length]),1) < 0) 811 goto err; 812 wr->length+=mac_size; 813 wr->input=p; 814 wr->data=p; 815 } 816 817 /* ssl3_enc can only have an error on read */ 818 s->method->ssl3_enc->enc(s,1); 819 820 /* record length after mac and block padding */ 821 s2n(wr->length,plen); 822 823 /* we should now have 824 * wr->data pointing to the encrypted data, which is 825 * wr->length long */ 826 wr->type=type; /* not needed but helps for debugging */ 827 wr->length+=SSL3_RT_HEADER_LENGTH; 828 829 if (create_empty_fragment) 830 { 831 /* we are in a recursive call; 832 * just return the length, don't write out anything here 833 */ 834 return wr->length; 835 } 836 837 /* now let's set up wb */ 838 wb->left = prefix_len + wr->length; 839 840 /* memorize arguments so that ssl3_write_pending can detect bad write retries later */ 841 s->s3->wpend_tot=len; 842 s->s3->wpend_buf=buf; 843 s->s3->wpend_type=type; 844 s->s3->wpend_ret=len; 845 846 /* we now just need to write the buffer */ 847 return ssl3_write_pending(s,type,buf,len); 848 err: 849 return -1; 850 } 851 852 /* if s->s3->wbuf.left != 0, we need to call this */ 853 int ssl3_write_pending(SSL *s, int type, const unsigned char *buf, 854 unsigned int len) 855 { 856 int i; 857 SSL3_BUFFER *wb=&(s->s3->wbuf); 858 859 /* XXXX */ 860 if ((s->s3->wpend_tot > (int)len) 861 || ((s->s3->wpend_buf != buf) && 862 !(s->mode & SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER)) 863 || (s->s3->wpend_type != type)) 864 { 865 SSLerr(SSL_F_SSL3_WRITE_PENDING,SSL_R_BAD_WRITE_RETRY); 866 return(-1); 867 } 868 869 for (;;) 870 { 871 clear_sys_error(); 872 if (s->wbio != NULL) 873 { 874 s->rwstate=SSL_WRITING; 875 i=BIO_write(s->wbio, 876 (char *)&(wb->buf[wb->offset]), 877 (unsigned int)wb->left); 878 } 879 else 880 { 881 SSLerr(SSL_F_SSL3_WRITE_PENDING,SSL_R_BIO_NOT_SET); 882 i= -1; 883 } 884 if (i == wb->left) 885 { 886 wb->left=0; 887 wb->offset+=i; 888 if (s->mode & SSL_MODE_RELEASE_BUFFERS) 889 ssl3_release_write_buffer(s); 890 s->rwstate=SSL_NOTHING; 891 return(s->s3->wpend_ret); 892 } 893 else if (i <= 0) { 894 if (s->version == DTLS1_VERSION || 895 s->version == DTLS1_BAD_VER) { 896 /* For DTLS, just drop it. That's kind of the whole 897 point in using a datagram service */ 898 wb->left = 0; 899 } 900 return(i); 901 } 902 wb->offset+=i; 903 wb->left-=i; 904 } 905 } 906 907 /* Return up to 'len' payload bytes received in 'type' records. 908 * 'type' is one of the following: 909 * 910 * - SSL3_RT_HANDSHAKE (when ssl3_get_message calls us) 911 * - SSL3_RT_APPLICATION_DATA (when ssl3_read calls us) 912 * - 0 (during a shutdown, no data has to be returned) 913 * 914 * If we don't have stored data to work from, read a SSL/TLS record first 915 * (possibly multiple records if we still don't have anything to return). 916 * 917 * This function must handle any surprises the peer may have for us, such as 918 * Alert records (e.g. close_notify), ChangeCipherSpec records (not really 919 * a surprise, but handled as if it were), or renegotiation requests. 920 * Also if record payloads contain fragments too small to process, we store 921 * them until there is enough for the respective protocol (the record protocol 922 * may use arbitrary fragmentation and even interleaving): 923 * Change cipher spec protocol 924 * just 1 byte needed, no need for keeping anything stored 925 * Alert protocol 926 * 2 bytes needed (AlertLevel, AlertDescription) 927 * Handshake protocol 928 * 4 bytes needed (HandshakeType, uint24 length) -- we just have 929 * to detect unexpected Client Hello and Hello Request messages 930 * here, anything else is handled by higher layers 931 * Application data protocol 932 * none of our business 933 */ 934 int ssl3_read_bytes(SSL *s, int type, unsigned char *buf, int len, int peek) 935 { 936 int al,i,j,ret; 937 unsigned int n; 938 SSL3_RECORD *rr; 939 void (*cb)(const SSL *ssl,int type2,int val)=NULL; 940 941 if (s->s3->rbuf.buf == NULL) /* Not initialized yet */ 942 if (!ssl3_setup_read_buffer(s)) 943 return(-1); 944 945 if ((type && (type != SSL3_RT_APPLICATION_DATA) && (type != SSL3_RT_HANDSHAKE) && type) || 946 (peek && (type != SSL3_RT_APPLICATION_DATA))) 947 { 948 SSLerr(SSL_F_SSL3_READ_BYTES, ERR_R_INTERNAL_ERROR); 949 return -1; 950 } 951 952 if ((type == SSL3_RT_HANDSHAKE) && (s->s3->handshake_fragment_len > 0)) 953 /* (partially) satisfy request from storage */ 954 { 955 unsigned char *src = s->s3->handshake_fragment; 956 unsigned char *dst = buf; 957 unsigned int k; 958 959 /* peek == 0 */ 960 n = 0; 961 while ((len > 0) && (s->s3->handshake_fragment_len > 0)) 962 { 963 *dst++ = *src++; 964 len--; s->s3->handshake_fragment_len--; 965 n++; 966 } 967 /* move any remaining fragment bytes: */ 968 for (k = 0; k < s->s3->handshake_fragment_len; k++) 969 s->s3->handshake_fragment[k] = *src++; 970 return n; 971 } 972 973 /* Now s->s3->handshake_fragment_len == 0 if type == SSL3_RT_HANDSHAKE. */ 974 975 if (!s->in_handshake && SSL_in_init(s)) 976 { 977 /* type == SSL3_RT_APPLICATION_DATA */ 978 i=s->handshake_func(s); 979 if (i < 0) return(i); 980 if (i == 0) 981 { 982 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE); 983 return(-1); 984 } 985 } 986 start: 987 s->rwstate=SSL_NOTHING; 988 989 /* s->s3->rrec.type - is the type of record 990 * s->s3->rrec.data, - data 991 * s->s3->rrec.off, - offset into 'data' for next read 992 * s->s3->rrec.length, - number of bytes. */ 993 rr = &(s->s3->rrec); 994 995 /* get new packet if necessary */ 996 if ((rr->length == 0) || (s->rstate == SSL_ST_READ_BODY)) 997 { 998 ret=ssl3_get_record(s); 999 if (ret <= 0) return(ret); 1000 } 1001 1002 /* we now have a packet which can be read and processed */ 1003 1004 if (s->s3->change_cipher_spec /* set when we receive ChangeCipherSpec, 1005 * reset by ssl3_get_finished */ 1006 && (rr->type != SSL3_RT_HANDSHAKE)) 1007 { 1008 al=SSL_AD_UNEXPECTED_MESSAGE; 1009 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_DATA_BETWEEN_CCS_AND_FINISHED); 1010 goto f_err; 1011 } 1012 1013 /* If the other end has shut down, throw anything we read away 1014 * (even in 'peek' mode) */ 1015 if (s->shutdown & SSL_RECEIVED_SHUTDOWN) 1016 { 1017 rr->length=0; 1018 s->rwstate=SSL_NOTHING; 1019 return(0); 1020 } 1021 1022 1023 if (type == rr->type) /* SSL3_RT_APPLICATION_DATA or SSL3_RT_HANDSHAKE */ 1024 { 1025 /* make sure that we are not getting application data when we 1026 * are doing a handshake for the first time */ 1027 if (SSL_in_init(s) && (type == SSL3_RT_APPLICATION_DATA) && 1028 (s->enc_read_ctx == NULL)) 1029 { 1030 al=SSL_AD_UNEXPECTED_MESSAGE; 1031 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_APP_DATA_IN_HANDSHAKE); 1032 goto f_err; 1033 } 1034 1035 if (len <= 0) return(len); 1036 1037 if ((unsigned int)len > rr->length) 1038 n = rr->length; 1039 else 1040 n = (unsigned int)len; 1041 1042 memcpy(buf,&(rr->data[rr->off]),n); 1043 if (!peek) 1044 { 1045 rr->length-=n; 1046 rr->off+=n; 1047 if (rr->length == 0) 1048 { 1049 s->rstate=SSL_ST_READ_HEADER; 1050 rr->off=0; 1051 if (s->mode & SSL_MODE_RELEASE_BUFFERS) 1052 ssl3_release_read_buffer(s); 1053 } 1054 } 1055 return(n); 1056 } 1057 1058 1059 /* If we get here, then type != rr->type; if we have a handshake 1060 * message, then it was unexpected (Hello Request or Client Hello). */ 1061 1062 /* In case of record types for which we have 'fragment' storage, 1063 * fill that so that we can process the data at a fixed place. 1064 */ 1065 { 1066 unsigned int dest_maxlen = 0; 1067 unsigned char *dest = NULL; 1068 unsigned int *dest_len = NULL; 1069 1070 if (rr->type == SSL3_RT_HANDSHAKE) 1071 { 1072 dest_maxlen = sizeof s->s3->handshake_fragment; 1073 dest = s->s3->handshake_fragment; 1074 dest_len = &s->s3->handshake_fragment_len; 1075 } 1076 else if (rr->type == SSL3_RT_ALERT) 1077 { 1078 dest_maxlen = sizeof s->s3->alert_fragment; 1079 dest = s->s3->alert_fragment; 1080 dest_len = &s->s3->alert_fragment_len; 1081 } 1082 1083 if (dest_maxlen > 0) 1084 { 1085 n = dest_maxlen - *dest_len; /* available space in 'dest' */ 1086 if (rr->length < n) 1087 n = rr->length; /* available bytes */ 1088 1089 /* now move 'n' bytes: */ 1090 while (n-- > 0) 1091 { 1092 dest[(*dest_len)++] = rr->data[rr->off++]; 1093 rr->length--; 1094 } 1095 1096 if (*dest_len < dest_maxlen) 1097 goto start; /* fragment was too small */ 1098 } 1099 } 1100 1101 /* s->s3->handshake_fragment_len == 4 iff rr->type == SSL3_RT_HANDSHAKE; 1102 * s->s3->alert_fragment_len == 2 iff rr->type == SSL3_RT_ALERT. 1103 * (Possibly rr is 'empty' now, i.e. rr->length may be 0.) */ 1104 1105 /* If we are a client, check for an incoming 'Hello Request': */ 1106 if ((!s->server) && 1107 (s->s3->handshake_fragment_len >= 4) && 1108 (s->s3->handshake_fragment[0] == SSL3_MT_HELLO_REQUEST) && 1109 (s->session != NULL) && (s->session->cipher != NULL)) 1110 { 1111 s->s3->handshake_fragment_len = 0; 1112 1113 if ((s->s3->handshake_fragment[1] != 0) || 1114 (s->s3->handshake_fragment[2] != 0) || 1115 (s->s3->handshake_fragment[3] != 0)) 1116 { 1117 al=SSL_AD_DECODE_ERROR; 1118 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_BAD_HELLO_REQUEST); 1119 goto f_err; 1120 } 1121 1122 if (s->msg_callback) 1123 s->msg_callback(0, s->version, SSL3_RT_HANDSHAKE, s->s3->handshake_fragment, 4, s, s->msg_callback_arg); 1124 1125 if (SSL_is_init_finished(s) && 1126 !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS) && 1127 !s->s3->renegotiate) 1128 { 1129 ssl3_renegotiate(s); 1130 if (ssl3_renegotiate_check(s)) 1131 { 1132 i=s->handshake_func(s); 1133 if (i < 0) return(i); 1134 if (i == 0) 1135 { 1136 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE); 1137 return(-1); 1138 } 1139 1140 if (!(s->mode & SSL_MODE_AUTO_RETRY)) 1141 { 1142 if (s->s3->rbuf.left == 0) /* no read-ahead left? */ 1143 { 1144 BIO *bio; 1145 /* In the case where we try to read application data, 1146 * but we trigger an SSL handshake, we return -1 with 1147 * the retry option set. Otherwise renegotiation may 1148 * cause nasty problems in the blocking world */ 1149 s->rwstate=SSL_READING; 1150 bio=SSL_get_rbio(s); 1151 BIO_clear_retry_flags(bio); 1152 BIO_set_retry_read(bio); 1153 return(-1); 1154 } 1155 } 1156 } 1157 } 1158 /* we either finished a handshake or ignored the request, 1159 * now try again to obtain the (application) data we were asked for */ 1160 goto start; 1161 } 1162 /* If we are a server and get a client hello when renegotiation isn't 1163 * allowed send back a no renegotiation alert and carry on. 1164 * WARNING: experimental code, needs reviewing (steve) 1165 */ 1166 if (s->server && 1167 SSL_is_init_finished(s) && 1168 !s->s3->send_connection_binding && 1169 (s->version > SSL3_VERSION) && 1170 (s->s3->handshake_fragment_len >= 4) && 1171 (s->s3->handshake_fragment[0] == SSL3_MT_CLIENT_HELLO) && 1172 (s->session != NULL) && (s->session->cipher != NULL) && 1173 !(s->ctx->options & SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION)) 1174 1175 { 1176 /*s->s3->handshake_fragment_len = 0;*/ 1177 rr->length = 0; 1178 ssl3_send_alert(s,SSL3_AL_WARNING, SSL_AD_NO_RENEGOTIATION); 1179 goto start; 1180 } 1181 if (s->s3->alert_fragment_len >= 2) 1182 { 1183 int alert_level = s->s3->alert_fragment[0]; 1184 int alert_descr = s->s3->alert_fragment[1]; 1185 1186 s->s3->alert_fragment_len = 0; 1187 1188 if (s->msg_callback) 1189 s->msg_callback(0, s->version, SSL3_RT_ALERT, s->s3->alert_fragment, 2, s, s->msg_callback_arg); 1190 1191 if (s->info_callback != NULL) 1192 cb=s->info_callback; 1193 else if (s->ctx->info_callback != NULL) 1194 cb=s->ctx->info_callback; 1195 1196 if (cb != NULL) 1197 { 1198 j = (alert_level << 8) | alert_descr; 1199 cb(s, SSL_CB_READ_ALERT, j); 1200 } 1201 1202 if (alert_level == 1) /* warning */ 1203 { 1204 s->s3->warn_alert = alert_descr; 1205 if (alert_descr == SSL_AD_CLOSE_NOTIFY) 1206 { 1207 s->shutdown |= SSL_RECEIVED_SHUTDOWN; 1208 return(0); 1209 } 1210 /* This is a warning but we receive it if we requested 1211 * renegotiation and the peer denied it. Terminate with 1212 * a fatal alert because if application tried to 1213 * renegotiatie it presumably had a good reason and 1214 * expects it to succeed. 1215 * 1216 * In future we might have a renegotiation where we 1217 * don't care if the peer refused it where we carry on. 1218 */ 1219 else if (alert_descr == SSL_AD_NO_RENEGOTIATION) 1220 { 1221 al = SSL_AD_HANDSHAKE_FAILURE; 1222 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_NO_RENEGOTIATION); 1223 goto f_err; 1224 } 1225 } 1226 else if (alert_level == 2) /* fatal */ 1227 { 1228 char tmp[16]; 1229 1230 s->rwstate=SSL_NOTHING; 1231 s->s3->fatal_alert = alert_descr; 1232 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_AD_REASON_OFFSET + alert_descr); 1233 BIO_snprintf(tmp,sizeof tmp,"%d",alert_descr); 1234 ERR_add_error_data(2,"SSL alert number ",tmp); 1235 s->shutdown|=SSL_RECEIVED_SHUTDOWN; 1236 SSL_CTX_remove_session(s->ctx,s->session); 1237 return(0); 1238 } 1239 else 1240 { 1241 al=SSL_AD_ILLEGAL_PARAMETER; 1242 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNKNOWN_ALERT_TYPE); 1243 goto f_err; 1244 } 1245 1246 goto start; 1247 } 1248 1249 if (s->shutdown & SSL_SENT_SHUTDOWN) /* but we have not received a shutdown */ 1250 { 1251 s->rwstate=SSL_NOTHING; 1252 rr->length=0; 1253 return(0); 1254 } 1255 1256 if (rr->type == SSL3_RT_CHANGE_CIPHER_SPEC) 1257 { 1258 /* 'Change Cipher Spec' is just a single byte, so we know 1259 * exactly what the record payload has to look like */ 1260 if ( (rr->length != 1) || (rr->off != 0) || 1261 (rr->data[0] != SSL3_MT_CCS)) 1262 { 1263 al=SSL_AD_ILLEGAL_PARAMETER; 1264 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_BAD_CHANGE_CIPHER_SPEC); 1265 goto f_err; 1266 } 1267 1268 /* Check we have a cipher to change to */ 1269 if (s->s3->tmp.new_cipher == NULL) 1270 { 1271 al=SSL_AD_UNEXPECTED_MESSAGE; 1272 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_CCS_RECEIVED_EARLY); 1273 goto f_err; 1274 } 1275 1276 rr->length=0; 1277 1278 if (s->msg_callback) 1279 s->msg_callback(0, s->version, SSL3_RT_CHANGE_CIPHER_SPEC, rr->data, 1, s, s->msg_callback_arg); 1280 1281 s->s3->change_cipher_spec=1; 1282 if (!ssl3_do_change_cipher_spec(s)) 1283 goto err; 1284 else 1285 goto start; 1286 } 1287 1288 /* Unexpected handshake message (Client Hello, or protocol violation) */ 1289 if ((s->s3->handshake_fragment_len >= 4) && !s->in_handshake) 1290 { 1291 if (((s->state&SSL_ST_MASK) == SSL_ST_OK) && 1292 !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS)) 1293 { 1294 #if 0 /* worked only because C operator preferences are not as expected (and 1295 * because this is not really needed for clients except for detecting 1296 * protocol violations): */ 1297 s->state=SSL_ST_BEFORE|(s->server) 1298 ?SSL_ST_ACCEPT 1299 :SSL_ST_CONNECT; 1300 #else 1301 s->state = s->server ? SSL_ST_ACCEPT : SSL_ST_CONNECT; 1302 #endif 1303 s->new_session=1; 1304 } 1305 i=s->handshake_func(s); 1306 if (i < 0) return(i); 1307 if (i == 0) 1308 { 1309 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE); 1310 return(-1); 1311 } 1312 1313 if (!(s->mode & SSL_MODE_AUTO_RETRY)) 1314 { 1315 if (s->s3->rbuf.left == 0) /* no read-ahead left? */ 1316 { 1317 BIO *bio; 1318 /* In the case where we try to read application data, 1319 * but we trigger an SSL handshake, we return -1 with 1320 * the retry option set. Otherwise renegotiation may 1321 * cause nasty problems in the blocking world */ 1322 s->rwstate=SSL_READING; 1323 bio=SSL_get_rbio(s); 1324 BIO_clear_retry_flags(bio); 1325 BIO_set_retry_read(bio); 1326 return(-1); 1327 } 1328 } 1329 goto start; 1330 } 1331 1332 switch (rr->type) 1333 { 1334 default: 1335 #ifndef OPENSSL_NO_TLS 1336 /* TLS just ignores unknown message types */ 1337 if (s->version == TLS1_VERSION) 1338 { 1339 rr->length = 0; 1340 goto start; 1341 } 1342 #endif 1343 al=SSL_AD_UNEXPECTED_MESSAGE; 1344 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNEXPECTED_RECORD); 1345 goto f_err; 1346 case SSL3_RT_CHANGE_CIPHER_SPEC: 1347 case SSL3_RT_ALERT: 1348 case SSL3_RT_HANDSHAKE: 1349 /* we already handled all of these, with the possible exception 1350 * of SSL3_RT_HANDSHAKE when s->in_handshake is set, but that 1351 * should not happen when type != rr->type */ 1352 al=SSL_AD_UNEXPECTED_MESSAGE; 1353 SSLerr(SSL_F_SSL3_READ_BYTES,ERR_R_INTERNAL_ERROR); 1354 goto f_err; 1355 case SSL3_RT_APPLICATION_DATA: 1356 /* At this point, we were expecting handshake data, 1357 * but have application data. If the library was 1358 * running inside ssl3_read() (i.e. in_read_app_data 1359 * is set) and it makes sense to read application data 1360 * at this point (session renegotiation not yet started), 1361 * we will indulge it. 1362 */ 1363 if (s->s3->in_read_app_data && 1364 (s->s3->total_renegotiations != 0) && 1365 (( 1366 (s->state & SSL_ST_CONNECT) && 1367 (s->state >= SSL3_ST_CW_CLNT_HELLO_A) && 1368 (s->state <= SSL3_ST_CR_SRVR_HELLO_A) 1369 ) || ( 1370 (s->state & SSL_ST_ACCEPT) && 1371 (s->state <= SSL3_ST_SW_HELLO_REQ_A) && 1372 (s->state >= SSL3_ST_SR_CLNT_HELLO_A) 1373 ) 1374 )) 1375 { 1376 s->s3->in_read_app_data=2; 1377 return(-1); 1378 } 1379 else 1380 { 1381 al=SSL_AD_UNEXPECTED_MESSAGE; 1382 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNEXPECTED_RECORD); 1383 goto f_err; 1384 } 1385 } 1386 /* not reached */ 1387 1388 f_err: 1389 ssl3_send_alert(s,SSL3_AL_FATAL,al); 1390 err: 1391 return(-1); 1392 } 1393 1394 int ssl3_do_change_cipher_spec(SSL *s) 1395 { 1396 int i; 1397 const char *sender; 1398 int slen; 1399 1400 if (s->state & SSL_ST_ACCEPT) 1401 i=SSL3_CHANGE_CIPHER_SERVER_READ; 1402 else 1403 i=SSL3_CHANGE_CIPHER_CLIENT_READ; 1404 1405 if (s->s3->tmp.key_block == NULL) 1406 { 1407 if (s->session == NULL) 1408 { 1409 /* might happen if dtls1_read_bytes() calls this */ 1410 SSLerr(SSL_F_SSL3_DO_CHANGE_CIPHER_SPEC,SSL_R_CCS_RECEIVED_EARLY); 1411 return (0); 1412 } 1413 1414 s->session->cipher=s->s3->tmp.new_cipher; 1415 if (!s->method->ssl3_enc->setup_key_block(s)) return(0); 1416 } 1417 1418 if (!s->method->ssl3_enc->change_cipher_state(s,i)) 1419 return(0); 1420 1421 /* we have to record the message digest at 1422 * this point so we can get it before we read 1423 * the finished message */ 1424 if (s->state & SSL_ST_CONNECT) 1425 { 1426 sender=s->method->ssl3_enc->server_finished_label; 1427 slen=s->method->ssl3_enc->server_finished_label_len; 1428 } 1429 else 1430 { 1431 sender=s->method->ssl3_enc->client_finished_label; 1432 slen=s->method->ssl3_enc->client_finished_label_len; 1433 } 1434 1435 s->s3->tmp.peer_finish_md_len = s->method->ssl3_enc->final_finish_mac(s, 1436 sender,slen,s->s3->tmp.peer_finish_md); 1437 1438 return(1); 1439 } 1440 1441 int ssl3_send_alert(SSL *s, int level, int desc) 1442 { 1443 /* Map tls/ssl alert value to correct one */ 1444 desc=s->method->ssl3_enc->alert_value(desc); 1445 if (s->version == SSL3_VERSION && desc == SSL_AD_PROTOCOL_VERSION) 1446 desc = SSL_AD_HANDSHAKE_FAILURE; /* SSL 3.0 does not have protocol_version alerts */ 1447 if (desc < 0) return -1; 1448 /* If a fatal one, remove from cache */ 1449 if ((level == 2) && (s->session != NULL)) 1450 SSL_CTX_remove_session(s->ctx,s->session); 1451 1452 s->s3->alert_dispatch=1; 1453 s->s3->send_alert[0]=level; 1454 s->s3->send_alert[1]=desc; 1455 if (s->s3->wbuf.left == 0) /* data still being written out? */ 1456 return s->method->ssl_dispatch_alert(s); 1457 /* else data is still being written out, we will get written 1458 * some time in the future */ 1459 return -1; 1460 } 1461 1462 int ssl3_dispatch_alert(SSL *s) 1463 { 1464 int i,j; 1465 void (*cb)(const SSL *ssl,int type,int val)=NULL; 1466 1467 s->s3->alert_dispatch=0; 1468 i = do_ssl3_write(s, SSL3_RT_ALERT, &s->s3->send_alert[0], 2, 0); 1469 if (i <= 0) 1470 { 1471 s->s3->alert_dispatch=1; 1472 } 1473 else 1474 { 1475 /* Alert sent to BIO. If it is important, flush it now. 1476 * If the message does not get sent due to non-blocking IO, 1477 * we will not worry too much. */ 1478 if (s->s3->send_alert[0] == SSL3_AL_FATAL) 1479 (void)BIO_flush(s->wbio); 1480 1481 if (s->msg_callback) 1482 s->msg_callback(1, s->version, SSL3_RT_ALERT, s->s3->send_alert, 2, s, s->msg_callback_arg); 1483 1484 if (s->info_callback != NULL) 1485 cb=s->info_callback; 1486 else if (s->ctx->info_callback != NULL) 1487 cb=s->ctx->info_callback; 1488 1489 if (cb != NULL) 1490 { 1491 j=(s->s3->send_alert[0]<<8)|s->s3->send_alert[1]; 1492 cb(s,SSL_CB_WRITE_ALERT,j); 1493 } 1494 } 1495 return(i); 1496 } 1497