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 #include <openssl/rand.h> 119 120 static int do_ssl3_write(SSL *s, int type, const unsigned char *buf, 121 unsigned int len, int create_empty_fragment); 122 static int ssl3_get_record(SSL *s); 123 124 int ssl3_read_n(SSL *s, int n, int max, int extend) 125 { 126 /* If extend == 0, obtain new n-byte packet; if extend == 1, increase 127 * packet by another n bytes. 128 * The packet will be in the sub-array of s->s3->rbuf.buf specified 129 * by s->packet and s->packet_length. 130 * (If s->read_ahead is set, 'max' bytes may be stored in rbuf 131 * [plus s->packet_length bytes if extend == 1].) 132 */ 133 int i,len,left; 134 long align=0; 135 unsigned char *pkt; 136 SSL3_BUFFER *rb; 137 138 if (n <= 0) return n; 139 140 rb = &(s->s3->rbuf); 141 if (rb->buf == NULL) 142 if (!ssl3_setup_read_buffer(s)) 143 return -1; 144 145 left = rb->left; 146 #if defined(SSL3_ALIGN_PAYLOAD) && SSL3_ALIGN_PAYLOAD!=0 147 align = (long)rb->buf + SSL3_RT_HEADER_LENGTH; 148 align = (-align)&(SSL3_ALIGN_PAYLOAD-1); 149 #endif 150 151 if (!extend) 152 { 153 /* start with empty packet ... */ 154 if (left == 0) 155 rb->offset = align; 156 else if (align != 0 && left >= SSL3_RT_HEADER_LENGTH) 157 { 158 /* check if next packet length is large 159 * enough to justify payload alignment... */ 160 pkt = rb->buf + rb->offset; 161 if (pkt[0] == SSL3_RT_APPLICATION_DATA 162 && (pkt[3]<<8|pkt[4]) >= 128) 163 { 164 /* Note that even if packet is corrupted 165 * and its length field is insane, we can 166 * only be led to wrong decision about 167 * whether memmove will occur or not. 168 * Header values has no effect on memmove 169 * arguments and therefore no buffer 170 * overrun can be triggered. */ 171 memmove (rb->buf+align,pkt,left); 172 rb->offset = align; 173 } 174 } 175 s->packet = rb->buf + rb->offset; 176 s->packet_length = 0; 177 /* ... now we can act as if 'extend' was set */ 178 } 179 180 /* For DTLS/UDP reads should not span multiple packets 181 * because the read operation returns the whole packet 182 * at once (as long as it fits into the buffer). */ 183 if (SSL_version(s) == DTLS1_VERSION || SSL_version(s) == DTLS1_BAD_VER) 184 { 185 if (left > 0 && n > left) 186 n = left; 187 } 188 189 /* if there is enough in the buffer from a previous read, take some */ 190 if (left >= n) 191 { 192 s->packet_length+=n; 193 rb->left=left-n; 194 rb->offset+=n; 195 return(n); 196 } 197 198 /* else we need to read more data */ 199 200 len = s->packet_length; 201 pkt = rb->buf+align; 202 /* Move any available bytes to front of buffer: 203 * 'len' bytes already pointed to by 'packet', 204 * 'left' extra ones at the end */ 205 if (s->packet != pkt) /* len > 0 */ 206 { 207 memmove(pkt, s->packet, len+left); 208 s->packet = pkt; 209 rb->offset = len + align; 210 } 211 212 if (n > (int)(rb->len - rb->offset)) /* does not happen */ 213 { 214 SSLerr(SSL_F_SSL3_READ_N,ERR_R_INTERNAL_ERROR); 215 return -1; 216 } 217 218 if (!s->read_ahead) 219 /* ignore max parameter */ 220 max = n; 221 else 222 { 223 if (max < n) 224 max = n; 225 if (max > (int)(rb->len - rb->offset)) 226 max = rb->len - rb->offset; 227 } 228 229 while (left < n) 230 { 231 /* Now we have len+left bytes at the front of s->s3->rbuf.buf 232 * and need to read in more until we have len+n (up to 233 * len+max if possible) */ 234 235 clear_sys_error(); 236 if (s->rbio != NULL) 237 { 238 s->rwstate=SSL_READING; 239 i=BIO_read(s->rbio,pkt+len+left, max-left); 240 } 241 else 242 { 243 SSLerr(SSL_F_SSL3_READ_N,SSL_R_READ_BIO_NOT_SET); 244 i = -1; 245 } 246 247 if (i <= 0) 248 { 249 rb->left = left; 250 if (s->mode & SSL_MODE_RELEASE_BUFFERS && 251 SSL_version(s) != DTLS1_VERSION && SSL_version(s) != DTLS1_BAD_VER) 252 if (len+left == 0) 253 ssl3_release_read_buffer(s); 254 return(i); 255 } 256 left+=i; 257 /* reads should *never* span multiple packets for DTLS because 258 * the underlying transport protocol is message oriented as opposed 259 * to byte oriented as in the TLS case. */ 260 if (SSL_version(s) == DTLS1_VERSION || SSL_version(s) == DTLS1_BAD_VER) 261 { 262 if (n > left) 263 n = left; /* makes the while condition false */ 264 } 265 } 266 267 /* done reading, now the book-keeping */ 268 rb->offset += n; 269 rb->left = left - n; 270 s->packet_length += n; 271 s->rwstate=SSL_NOTHING; 272 return(n); 273 } 274 275 /* Call this to get a new input record. 276 * It will return <= 0 if more data is needed, normally due to an error 277 * or non-blocking IO. 278 * When it finishes, one packet has been decoded and can be found in 279 * ssl->s3->rrec.type - is the type of record 280 * ssl->s3->rrec.data, - data 281 * ssl->s3->rrec.length, - number of bytes 282 */ 283 /* used only by ssl3_read_bytes */ 284 static int ssl3_get_record(SSL *s) 285 { 286 int ssl_major,ssl_minor,al; 287 int enc_err,n,i,ret= -1; 288 SSL3_RECORD *rr; 289 SSL_SESSION *sess; 290 unsigned char *p; 291 unsigned char md[EVP_MAX_MD_SIZE]; 292 short version; 293 int mac_size; 294 int clear=0; 295 size_t extra; 296 int decryption_failed_or_bad_record_mac = 0; 297 unsigned char *mac = NULL; 298 #if defined(SSL3_ALIGN_PAYLOAD) && SSL3_ALIGN_PAYLOAD!=0 299 long align=SSL3_ALIGN_PAYLOAD; 300 #else 301 long align=0; 302 #endif 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 (!(SSL_get_mode(s) & SSL_MODE_SMALL_BUFFERS) && 312 extra && !s->s3->init_extra) 313 { 314 /* An application error: SLS_OP_MICROSOFT_BIG_SSLV3_BUFFER 315 * set after ssl3_setup_buffers() was done */ 316 SSLerr(SSL_F_SSL3_GET_RECORD, ERR_R_INTERNAL_ERROR); 317 return -1; 318 } 319 320 again: 321 /* check if we have the header */ 322 if ( (s->rstate != SSL_ST_READ_BODY) || 323 (s->packet_length < SSL3_RT_HEADER_LENGTH)) 324 { 325 n=ssl3_read_n(s, SSL3_RT_HEADER_LENGTH, s->s3->rbuf.len, 0); 326 if (n <= 0) return(n); /* error or non-blocking */ 327 s->rstate=SSL_ST_READ_BODY; 328 329 p=s->packet; 330 331 /* Pull apart the header into the SSL3_RECORD */ 332 rr->type= *(p++); 333 ssl_major= *(p++); 334 ssl_minor= *(p++); 335 version=(ssl_major<<8)|ssl_minor; 336 n2s(p,rr->length); 337 #if 0 338 fprintf(stderr, "Record type=%d, Length=%d\n", rr->type, rr->length); 339 #endif 340 341 /* Lets check version */ 342 if (!s->first_packet) 343 { 344 if (version != s->version) 345 { 346 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_WRONG_VERSION_NUMBER); 347 if ((s->version & 0xFF00) == (version & 0xFF00)) 348 /* Send back error using their minor version number :-) */ 349 s->version = (unsigned short)version; 350 al=SSL_AD_PROTOCOL_VERSION; 351 goto f_err; 352 } 353 } 354 355 if ((version>>8) != SSL3_VERSION_MAJOR) 356 { 357 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_WRONG_VERSION_NUMBER); 358 goto err; 359 } 360 361 /* If we receive a valid record larger than the current buffer size, 362 * allocate some memory for it. 363 */ 364 if (rr->length > s->s3->rbuf.len - SSL3_RT_HEADER_LENGTH - align) 365 { 366 if ((p=OPENSSL_realloc(s->s3->rbuf.buf, rr->length + SSL3_RT_HEADER_LENGTH + align))==NULL) 367 { 368 SSLerr(SSL_F_SSL3_GET_RECORD,ERR_R_MALLOC_FAILURE); 369 goto err; 370 } 371 s->s3->rbuf.buf=p; 372 s->s3->rbuf.len=rr->length + SSL3_RT_HEADER_LENGTH + align; 373 s->packet= &(s->s3->rbuf.buf[0]); 374 } 375 376 if (rr->length > s->s3->rbuf.len - SSL3_RT_HEADER_LENGTH) 377 { 378 al=SSL_AD_RECORD_OVERFLOW; 379 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_PACKET_LENGTH_TOO_LONG); 380 goto f_err; 381 } 382 383 /* now s->rstate == SSL_ST_READ_BODY */ 384 } 385 386 /* s->rstate == SSL_ST_READ_BODY, get and decode the data */ 387 388 if (rr->length > s->packet_length-SSL3_RT_HEADER_LENGTH) 389 { 390 /* now s->packet_length == SSL3_RT_HEADER_LENGTH */ 391 i=rr->length; 392 n=ssl3_read_n(s,i,i,1); 393 if (n <= 0) return(n); /* error or non-blocking io */ 394 /* now n == rr->length, 395 * and s->packet_length == SSL3_RT_HEADER_LENGTH + rr->length */ 396 } 397 398 s->rstate=SSL_ST_READ_HEADER; /* set state for later operations */ 399 400 /* At this point, s->packet_length == SSL3_RT_HEADER_LNGTH + rr->length, 401 * and we have that many bytes in s->packet 402 */ 403 rr->input= &(s->packet[SSL3_RT_HEADER_LENGTH]); 404 405 /* ok, we can now read from 's->packet' data into 'rr' 406 * rr->input points at rr->length bytes, which 407 * need to be copied into rr->data by either 408 * the decryption or by the decompression 409 * When the data is 'copied' into the rr->data buffer, 410 * rr->input will be pointed at the new buffer */ 411 412 /* We now have - encrypted [ MAC [ compressed [ plain ] ] ] 413 * rr->length bytes of encrypted compressed stuff. */ 414 415 /* check is not needed I believe */ 416 if (rr->length > SSL3_RT_MAX_ENCRYPTED_LENGTH+extra) 417 { 418 al=SSL_AD_RECORD_OVERFLOW; 419 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_ENCRYPTED_LENGTH_TOO_LONG); 420 goto f_err; 421 } 422 423 /* decrypt in place in 'rr->input' */ 424 rr->data=rr->input; 425 426 enc_err = s->method->ssl3_enc->enc(s,0); 427 if (enc_err <= 0) 428 { 429 if (enc_err == 0) 430 /* SSLerr() and ssl3_send_alert() have been called */ 431 goto err; 432 433 /* Otherwise enc_err == -1, which indicates bad padding 434 * (rec->length has not been changed in this case). 435 * To minimize information leaked via timing, we will perform 436 * the MAC computation anyway. */ 437 decryption_failed_or_bad_record_mac = 1; 438 } 439 440 #ifdef TLS_DEBUG 441 printf("dec %d\n",rr->length); 442 { unsigned int z; for (z=0; z<rr->length; z++) printf("%02X%c",rr->data[z],((z+1)%16)?' ':'\n'); } 443 printf("\n"); 444 #endif 445 446 /* r->length is now the compressed data plus mac */ 447 if ( (sess == NULL) || 448 (s->enc_read_ctx == NULL) || 449 (EVP_MD_CTX_md(s->read_hash) == NULL)) 450 clear=1; 451 452 if (!clear) 453 { 454 /* !clear => s->read_hash != NULL => mac_size != -1 */ 455 mac_size=EVP_MD_CTX_size(s->read_hash); 456 OPENSSL_assert(mac_size >= 0); 457 458 if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH+extra+mac_size) 459 { 460 #if 0 /* OK only for stream ciphers (then rr->length is visible from ciphertext anyway) */ 461 al=SSL_AD_RECORD_OVERFLOW; 462 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_PRE_MAC_LENGTH_TOO_LONG); 463 goto f_err; 464 #else 465 decryption_failed_or_bad_record_mac = 1; 466 #endif 467 } 468 /* check the MAC for rr->input (it's in mac_size bytes at the tail) */ 469 if (rr->length >= (unsigned int)mac_size) 470 { 471 rr->length -= mac_size; 472 mac = &rr->data[rr->length]; 473 } 474 else 475 { 476 /* record (minus padding) is too short to contain a MAC */ 477 #if 0 /* OK only for stream ciphers */ 478 al=SSL_AD_DECODE_ERROR; 479 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_LENGTH_TOO_SHORT); 480 goto f_err; 481 #else 482 decryption_failed_or_bad_record_mac = 1; 483 rr->length = 0; 484 #endif 485 } 486 i=s->method->ssl3_enc->mac(s,md,0); 487 if (i < 0 || mac == NULL || memcmp(md, mac, (size_t)mac_size) != 0) 488 { 489 decryption_failed_or_bad_record_mac = 1; 490 } 491 } 492 493 if (decryption_failed_or_bad_record_mac) 494 { 495 /* A separate 'decryption_failed' alert was introduced with TLS 1.0, 496 * SSL 3.0 only has 'bad_record_mac'. But unless a decryption 497 * failure is directly visible from the ciphertext anyway, 498 * we should not reveal which kind of error occured -- this 499 * might become visible to an attacker (e.g. via a logfile) */ 500 al=SSL_AD_BAD_RECORD_MAC; 501 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_DECRYPTION_FAILED_OR_BAD_RECORD_MAC); 502 goto f_err; 503 } 504 505 /* r->length is now just compressed */ 506 if (s->expand != NULL) 507 { 508 if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH+extra) 509 { 510 al=SSL_AD_RECORD_OVERFLOW; 511 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_COMPRESSED_LENGTH_TOO_LONG); 512 goto f_err; 513 } 514 if (!ssl3_do_uncompress(s)) 515 { 516 al=SSL_AD_DECOMPRESSION_FAILURE; 517 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_BAD_DECOMPRESSION); 518 goto f_err; 519 } 520 } 521 522 if (rr->length > SSL3_RT_MAX_PLAIN_LENGTH+extra) 523 { 524 al=SSL_AD_RECORD_OVERFLOW; 525 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_DATA_LENGTH_TOO_LONG); 526 goto f_err; 527 } 528 529 rr->off=0; 530 /* So at this point the following is true 531 * ssl->s3->rrec.type is the type of record 532 * ssl->s3->rrec.length == number of bytes in record 533 * ssl->s3->rrec.off == offset to first valid byte 534 * ssl->s3->rrec.data == where to take bytes from, increment 535 * after use :-). 536 */ 537 538 /* we have pulled in a full packet so zero things */ 539 s->packet_length=0; 540 541 /* just read a 0 length packet */ 542 if (rr->length == 0) goto again; 543 544 #if 0 545 fprintf(stderr, "Ultimate Record type=%d, Length=%d\n", rr->type, rr->length); 546 #endif 547 548 return(1); 549 550 f_err: 551 ssl3_send_alert(s,SSL3_AL_FATAL,al); 552 err: 553 return(ret); 554 } 555 556 int ssl3_do_uncompress(SSL *ssl) 557 { 558 #ifndef OPENSSL_NO_COMP 559 int i; 560 SSL3_RECORD *rr; 561 562 rr= &(ssl->s3->rrec); 563 i=COMP_expand_block(ssl->expand,rr->comp, 564 SSL3_RT_MAX_PLAIN_LENGTH,rr->data,(int)rr->length); 565 if (i < 0) 566 return(0); 567 else 568 rr->length=i; 569 rr->data=rr->comp; 570 #endif 571 return(1); 572 } 573 574 int ssl3_do_compress(SSL *ssl) 575 { 576 #ifndef OPENSSL_NO_COMP 577 int i; 578 SSL3_RECORD *wr; 579 580 wr= &(ssl->s3->wrec); 581 i=COMP_compress_block(ssl->compress,wr->data, 582 SSL3_RT_MAX_COMPRESSED_LENGTH, 583 wr->input,(int)wr->length); 584 if (i < 0) 585 return(0); 586 else 587 wr->length=i; 588 589 wr->input=wr->data; 590 #endif 591 return(1); 592 } 593 594 /* Call this to write data in records of type 'type' 595 * It will return <= 0 if not all data has been sent or non-blocking IO. 596 */ 597 int ssl3_write_bytes(SSL *s, int type, const void *buf_, int len) 598 { 599 const unsigned char *buf=buf_; 600 unsigned int tot,n,nw; 601 int i; 602 unsigned int max_plain_length; 603 604 s->rwstate=SSL_NOTHING; 605 tot=s->s3->wnum; 606 s->s3->wnum=0; 607 608 if (SSL_in_init(s) && !s->in_handshake) 609 { 610 i=s->handshake_func(s); 611 if (i < 0) return(i); 612 if (i == 0) 613 { 614 SSLerr(SSL_F_SSL3_WRITE_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE); 615 return -1; 616 } 617 } 618 619 n=(len-tot); 620 for (;;) 621 { 622 if (type == SSL3_RT_APPLICATION_DATA && (SSL_get_mode(s) & SSL_MODE_SMALL_BUFFERS)) 623 max_plain_length = SSL3_RT_DEFAULT_PLAIN_LENGTH; 624 else 625 max_plain_length = s->max_send_fragment; 626 627 if (n > max_plain_length) 628 nw = max_plain_length; 629 else 630 nw=n; 631 632 i=do_ssl3_write(s, type, &(buf[tot]), nw, 0); 633 if (i <= 0) 634 { 635 s->s3->wnum=tot; 636 return i; 637 } 638 639 if ((i == (int)n) || 640 (type == SSL3_RT_APPLICATION_DATA && 641 (s->mode & SSL_MODE_ENABLE_PARTIAL_WRITE))) 642 { 643 /* next chunk of data should get another prepended empty fragment 644 * in ciphersuites with known-IV weakness: */ 645 s->s3->empty_fragment_done = 0; 646 647 return tot+i; 648 } 649 650 n-=i; 651 tot+=i; 652 } 653 } 654 655 static int do_ssl3_write(SSL *s, int type, const unsigned char *buf, 656 unsigned int len, int create_empty_fragment) 657 { 658 unsigned char *p,*plen; 659 int i,mac_size,clear=0; 660 int prefix_len=0; 661 int eivlen; 662 long align=0; 663 SSL3_RECORD *wr; 664 SSL3_BUFFER *wb=&(s->s3->wbuf); 665 SSL_SESSION *sess; 666 667 if (wb->buf == NULL) 668 if (!ssl3_setup_write_buffer(s)) 669 return -1; 670 671 /* first check if there is a SSL3_BUFFER still being written 672 * out. This will happen with non blocking IO */ 673 if (wb->left != 0) 674 return(ssl3_write_pending(s,type,buf,len)); 675 676 /* If we have an alert to send, lets send it */ 677 if (s->s3->alert_dispatch) 678 { 679 i=s->method->ssl_dispatch_alert(s); 680 if (i <= 0) 681 return(i); 682 /* if it went, fall through and send more stuff */ 683 } 684 685 if (len == 0 && !create_empty_fragment) 686 return 0; 687 688 wr= &(s->s3->wrec); 689 sess=s->session; 690 691 if ( (sess == NULL) || 692 (s->enc_write_ctx == NULL) || 693 (EVP_MD_CTX_md(s->write_hash) == NULL)) 694 { 695 #if 1 696 clear=s->enc_write_ctx?0:1; /* must be AEAD cipher */ 697 #else 698 clear=1; 699 #endif 700 mac_size=0; 701 } 702 else 703 { 704 mac_size=EVP_MD_CTX_size(s->write_hash); 705 if (mac_size < 0) 706 goto err; 707 } 708 709 /* 'create_empty_fragment' is true only when this function calls itself */ 710 if (!clear && !create_empty_fragment && !s->s3->empty_fragment_done) 711 { 712 /* countermeasure against known-IV weakness in CBC ciphersuites 713 * (see http://www.openssl.org/~bodo/tls-cbc.txt) */ 714 715 if (s->s3->need_empty_fragments && type == SSL3_RT_APPLICATION_DATA) 716 { 717 /* recursive function call with 'create_empty_fragment' set; 718 * this prepares and buffers the data for an empty fragment 719 * (these 'prefix_len' bytes are sent out later 720 * together with the actual payload) */ 721 prefix_len = do_ssl3_write(s, type, buf, 0, 1); 722 if (prefix_len <= 0) 723 goto err; 724 725 if (prefix_len > 726 (SSL3_RT_HEADER_LENGTH + SSL3_RT_SEND_MAX_ENCRYPTED_OVERHEAD)) 727 { 728 /* insufficient space */ 729 SSLerr(SSL_F_DO_SSL3_WRITE, ERR_R_INTERNAL_ERROR); 730 goto err; 731 } 732 } 733 734 s->s3->empty_fragment_done = 1; 735 } 736 737 /* resize if necessary to hold the data. */ 738 if (len + SSL3_RT_DEFAULT_WRITE_OVERHEAD > wb->len) 739 { 740 if ((p=OPENSSL_realloc(wb->buf, len + SSL3_RT_DEFAULT_WRITE_OVERHEAD))==NULL) 741 { 742 SSLerr(SSL_F_DO_SSL3_WRITE,ERR_R_MALLOC_FAILURE); 743 goto err; 744 } 745 wb->buf = p; 746 wb->len = len + SSL3_RT_DEFAULT_WRITE_OVERHEAD; 747 } 748 749 if (create_empty_fragment) 750 { 751 #if defined(SSL3_ALIGN_PAYLOAD) && SSL3_ALIGN_PAYLOAD!=0 752 /* extra fragment would be couple of cipher blocks, 753 * which would be multiple of SSL3_ALIGN_PAYLOAD, so 754 * if we want to align the real payload, then we can 755 * just pretent we simply have two headers. */ 756 align = (long)wb->buf + 2*SSL3_RT_HEADER_LENGTH; 757 align = (-align)&(SSL3_ALIGN_PAYLOAD-1); 758 #endif 759 p = wb->buf + align; 760 wb->offset = align; 761 } 762 else if (prefix_len) 763 { 764 p = wb->buf + wb->offset + prefix_len; 765 } 766 else 767 { 768 #if defined(SSL3_ALIGN_PAYLOAD) && SSL3_ALIGN_PAYLOAD!=0 769 align = (long)wb->buf + SSL3_RT_HEADER_LENGTH; 770 align = (-align)&(SSL3_ALIGN_PAYLOAD-1); 771 #endif 772 p = wb->buf + align; 773 wb->offset = align; 774 } 775 776 /* write the header */ 777 778 *(p++)=type&0xff; 779 wr->type=type; 780 781 *(p++)=(s->version>>8); 782 /* Some servers hang if iniatial client hello is larger than 256 783 * bytes and record version number > TLS 1.0 784 */ 785 if (s->state == SSL3_ST_CW_CLNT_HELLO_B 786 && TLS1_get_version(s) > TLS1_VERSION) 787 *(p++) = 0x1; 788 else 789 *(p++)=s->version&0xff; 790 791 /* field where we are to write out packet length */ 792 plen=p; 793 p+=2; 794 /* Explicit IV length, block ciphers and TLS version 1.1 or later */ 795 if (s->enc_write_ctx && s->version >= TLS1_1_VERSION) 796 { 797 int mode = EVP_CIPHER_CTX_mode(s->enc_write_ctx); 798 if (mode == EVP_CIPH_CBC_MODE) 799 { 800 eivlen = EVP_CIPHER_CTX_iv_length(s->enc_write_ctx); 801 if (eivlen <= 1) 802 eivlen = 0; 803 } 804 /* Need explicit part of IV for GCM mode */ 805 else if (mode == EVP_CIPH_GCM_MODE) 806 eivlen = EVP_GCM_TLS_EXPLICIT_IV_LEN; 807 else 808 eivlen = 0; 809 } 810 else 811 eivlen = 0; 812 813 /* lets setup the record stuff. */ 814 wr->data=p + eivlen; 815 wr->length=(int)len; 816 wr->input=(unsigned char *)buf; 817 818 /* we now 'read' from wr->input, wr->length bytes into 819 * wr->data */ 820 821 /* first we compress */ 822 if (s->compress != NULL) 823 { 824 if (!ssl3_do_compress(s)) 825 { 826 SSLerr(SSL_F_DO_SSL3_WRITE,SSL_R_COMPRESSION_FAILURE); 827 goto err; 828 } 829 } 830 else 831 { 832 memcpy(wr->data,wr->input,wr->length); 833 wr->input=wr->data; 834 } 835 836 /* we should still have the output to wr->data and the input 837 * from wr->input. Length should be wr->length. 838 * wr->data still points in the wb->buf */ 839 840 if (mac_size != 0) 841 { 842 if (s->method->ssl3_enc->mac(s,&(p[wr->length + eivlen]),1) < 0) 843 goto err; 844 wr->length+=mac_size; 845 } 846 847 wr->input=p; 848 wr->data=p; 849 850 if (eivlen) 851 { 852 /* if (RAND_pseudo_bytes(p, eivlen) <= 0) 853 goto err; */ 854 wr->length += eivlen; 855 } 856 857 /* ssl3_enc can only have an error on read */ 858 s->method->ssl3_enc->enc(s,1); 859 860 /* record length after mac and block padding */ 861 s2n(wr->length,plen); 862 863 /* we should now have 864 * wr->data pointing to the encrypted data, which is 865 * wr->length long */ 866 wr->type=type; /* not needed but helps for debugging */ 867 wr->length+=SSL3_RT_HEADER_LENGTH; 868 869 if (create_empty_fragment) 870 { 871 /* we are in a recursive call; 872 * just return the length, don't write out anything here 873 */ 874 return wr->length; 875 } 876 877 /* now let's set up wb */ 878 wb->left = prefix_len + wr->length; 879 880 /* memorize arguments so that ssl3_write_pending can detect bad write retries later */ 881 s->s3->wpend_tot=len; 882 s->s3->wpend_buf=buf; 883 s->s3->wpend_type=type; 884 s->s3->wpend_ret=len; 885 886 /* we now just need to write the buffer */ 887 return ssl3_write_pending(s,type,buf,len); 888 err: 889 return -1; 890 } 891 892 /* if s->s3->wbuf.left != 0, we need to call this */ 893 int ssl3_write_pending(SSL *s, int type, const unsigned char *buf, 894 unsigned int len) 895 { 896 int i; 897 SSL3_BUFFER *wb=&(s->s3->wbuf); 898 899 /* XXXX */ 900 if ((s->s3->wpend_tot > (int)len) 901 || ((s->s3->wpend_buf != buf) && 902 !(s->mode & SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER)) 903 || (s->s3->wpend_type != type)) 904 { 905 SSLerr(SSL_F_SSL3_WRITE_PENDING,SSL_R_BAD_WRITE_RETRY); 906 return(-1); 907 } 908 909 for (;;) 910 { 911 clear_sys_error(); 912 if (s->wbio != NULL) 913 { 914 s->rwstate=SSL_WRITING; 915 i=BIO_write(s->wbio, 916 (char *)&(wb->buf[wb->offset]), 917 (unsigned int)wb->left); 918 } 919 else 920 { 921 SSLerr(SSL_F_SSL3_WRITE_PENDING,SSL_R_BIO_NOT_SET); 922 i= -1; 923 } 924 if (i == wb->left) 925 { 926 wb->left=0; 927 wb->offset+=i; 928 if (s->mode & SSL_MODE_RELEASE_BUFFERS && 929 SSL_version(s) != DTLS1_VERSION && SSL_version(s) != DTLS1_BAD_VER) 930 ssl3_release_write_buffer(s); 931 s->rwstate=SSL_NOTHING; 932 return(s->s3->wpend_ret); 933 } 934 else if (i <= 0) { 935 if (s->version == DTLS1_VERSION || 936 s->version == DTLS1_BAD_VER) { 937 /* For DTLS, just drop it. That's kind of the whole 938 point in using a datagram service */ 939 wb->left = 0; 940 } 941 return(i); 942 } 943 wb->offset+=i; 944 wb->left-=i; 945 } 946 } 947 948 /* Return up to 'len' payload bytes received in 'type' records. 949 * 'type' is one of the following: 950 * 951 * - SSL3_RT_HANDSHAKE (when ssl3_get_message calls us) 952 * - SSL3_RT_APPLICATION_DATA (when ssl3_read calls us) 953 * - 0 (during a shutdown, no data has to be returned) 954 * 955 * If we don't have stored data to work from, read a SSL/TLS record first 956 * (possibly multiple records if we still don't have anything to return). 957 * 958 * This function must handle any surprises the peer may have for us, such as 959 * Alert records (e.g. close_notify), ChangeCipherSpec records (not really 960 * a surprise, but handled as if it were), or renegotiation requests. 961 * Also if record payloads contain fragments too small to process, we store 962 * them until there is enough for the respective protocol (the record protocol 963 * may use arbitrary fragmentation and even interleaving): 964 * Change cipher spec protocol 965 * just 1 byte needed, no need for keeping anything stored 966 * Alert protocol 967 * 2 bytes needed (AlertLevel, AlertDescription) 968 * Handshake protocol 969 * 4 bytes needed (HandshakeType, uint24 length) -- we just have 970 * to detect unexpected Client Hello and Hello Request messages 971 * here, anything else is handled by higher layers 972 * Application data protocol 973 * none of our business 974 */ 975 int ssl3_read_bytes(SSL *s, int type, unsigned char *buf, int len, int peek) 976 { 977 int al,i,j,ret; 978 unsigned int n; 979 SSL3_RECORD *rr; 980 void (*cb)(const SSL *ssl,int type2,int val)=NULL; 981 982 if (s->s3->rbuf.buf == NULL) /* Not initialized yet */ 983 if (!ssl3_setup_read_buffer(s)) 984 return(-1); 985 986 if ((type && (type != SSL3_RT_APPLICATION_DATA) && (type != SSL3_RT_HANDSHAKE) && type) || 987 (peek && (type != SSL3_RT_APPLICATION_DATA))) 988 { 989 SSLerr(SSL_F_SSL3_READ_BYTES, ERR_R_INTERNAL_ERROR); 990 return -1; 991 } 992 993 if ((type == SSL3_RT_HANDSHAKE) && (s->s3->handshake_fragment_len > 0)) 994 /* (partially) satisfy request from storage */ 995 { 996 unsigned char *src = s->s3->handshake_fragment; 997 unsigned char *dst = buf; 998 unsigned int k; 999 1000 /* peek == 0 */ 1001 n = 0; 1002 while ((len > 0) && (s->s3->handshake_fragment_len > 0)) 1003 { 1004 *dst++ = *src++; 1005 len--; s->s3->handshake_fragment_len--; 1006 n++; 1007 } 1008 /* move any remaining fragment bytes: */ 1009 for (k = 0; k < s->s3->handshake_fragment_len; k++) 1010 s->s3->handshake_fragment[k] = *src++; 1011 return n; 1012 } 1013 1014 /* Now s->s3->handshake_fragment_len == 0 if type == SSL3_RT_HANDSHAKE. */ 1015 1016 if (!s->in_handshake && SSL_in_init(s)) 1017 { 1018 /* type == SSL3_RT_APPLICATION_DATA */ 1019 i=s->handshake_func(s); 1020 if (i < 0) return(i); 1021 if (i == 0) 1022 { 1023 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE); 1024 return(-1); 1025 } 1026 } 1027 start: 1028 s->rwstate=SSL_NOTHING; 1029 1030 /* s->s3->rrec.type - is the type of record 1031 * s->s3->rrec.data, - data 1032 * s->s3->rrec.off, - offset into 'data' for next read 1033 * s->s3->rrec.length, - number of bytes. */ 1034 rr = &(s->s3->rrec); 1035 1036 /* get new packet if necessary */ 1037 if ((rr->length == 0) || (s->rstate == SSL_ST_READ_BODY)) 1038 { 1039 ret=ssl3_get_record(s); 1040 if (ret <= 0) return(ret); 1041 } 1042 1043 /* we now have a packet which can be read and processed */ 1044 1045 if (s->s3->change_cipher_spec /* set when we receive ChangeCipherSpec, 1046 * reset by ssl3_get_finished */ 1047 && (rr->type != SSL3_RT_HANDSHAKE)) 1048 { 1049 al=SSL_AD_UNEXPECTED_MESSAGE; 1050 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_DATA_BETWEEN_CCS_AND_FINISHED); 1051 goto f_err; 1052 } 1053 1054 /* If the other end has shut down, throw anything we read away 1055 * (even in 'peek' mode) */ 1056 if (s->shutdown & SSL_RECEIVED_SHUTDOWN) 1057 { 1058 rr->length=0; 1059 s->rwstate=SSL_NOTHING; 1060 return(0); 1061 } 1062 1063 1064 if (type == rr->type) /* SSL3_RT_APPLICATION_DATA or SSL3_RT_HANDSHAKE */ 1065 { 1066 /* make sure that we are not getting application data when we 1067 * are doing a handshake for the first time */ 1068 if (SSL_in_init(s) && (type == SSL3_RT_APPLICATION_DATA) && 1069 (s->enc_read_ctx == NULL)) 1070 { 1071 al=SSL_AD_UNEXPECTED_MESSAGE; 1072 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_APP_DATA_IN_HANDSHAKE); 1073 goto f_err; 1074 } 1075 1076 if (len <= 0) return(len); 1077 1078 if ((unsigned int)len > rr->length) 1079 n = rr->length; 1080 else 1081 n = (unsigned int)len; 1082 1083 memcpy(buf,&(rr->data[rr->off]),n); 1084 if (!peek) 1085 { 1086 rr->length-=n; 1087 rr->off+=n; 1088 if (rr->length == 0) 1089 { 1090 s->rstate=SSL_ST_READ_HEADER; 1091 rr->off=0; 1092 if (s->mode & SSL_MODE_RELEASE_BUFFERS) 1093 ssl3_release_read_buffer(s); 1094 } 1095 } 1096 return(n); 1097 } 1098 1099 1100 /* If we get here, then type != rr->type; if we have a handshake 1101 * message, then it was unexpected (Hello Request or Client Hello). */ 1102 1103 /* In case of record types for which we have 'fragment' storage, 1104 * fill that so that we can process the data at a fixed place. 1105 */ 1106 { 1107 unsigned int dest_maxlen = 0; 1108 unsigned char *dest = NULL; 1109 unsigned int *dest_len = NULL; 1110 1111 if (rr->type == SSL3_RT_HANDSHAKE) 1112 { 1113 dest_maxlen = sizeof s->s3->handshake_fragment; 1114 dest = s->s3->handshake_fragment; 1115 dest_len = &s->s3->handshake_fragment_len; 1116 } 1117 else if (rr->type == SSL3_RT_ALERT) 1118 { 1119 dest_maxlen = sizeof s->s3->alert_fragment; 1120 dest = s->s3->alert_fragment; 1121 dest_len = &s->s3->alert_fragment_len; 1122 } 1123 #ifndef OPENSSL_NO_HEARTBEATS 1124 else if (rr->type == TLS1_RT_HEARTBEAT) 1125 { 1126 tls1_process_heartbeat(s); 1127 1128 /* Exit and notify application to read again */ 1129 rr->length = 0; 1130 s->rwstate=SSL_READING; 1131 BIO_clear_retry_flags(SSL_get_rbio(s)); 1132 BIO_set_retry_read(SSL_get_rbio(s)); 1133 return(-1); 1134 } 1135 #endif 1136 1137 if (dest_maxlen > 0) 1138 { 1139 n = dest_maxlen - *dest_len; /* available space in 'dest' */ 1140 if (rr->length < n) 1141 n = rr->length; /* available bytes */ 1142 1143 /* now move 'n' bytes: */ 1144 while (n-- > 0) 1145 { 1146 dest[(*dest_len)++] = rr->data[rr->off++]; 1147 rr->length--; 1148 } 1149 1150 if (*dest_len < dest_maxlen) 1151 goto start; /* fragment was too small */ 1152 } 1153 } 1154 1155 /* s->s3->handshake_fragment_len == 4 iff rr->type == SSL3_RT_HANDSHAKE; 1156 * s->s3->alert_fragment_len == 2 iff rr->type == SSL3_RT_ALERT. 1157 * (Possibly rr is 'empty' now, i.e. rr->length may be 0.) */ 1158 1159 /* If we are a client, check for an incoming 'Hello Request': */ 1160 if ((!s->server) && 1161 (s->s3->handshake_fragment_len >= 4) && 1162 (s->s3->handshake_fragment[0] == SSL3_MT_HELLO_REQUEST) && 1163 (s->session != NULL) && (s->session->cipher != NULL)) 1164 { 1165 s->s3->handshake_fragment_len = 0; 1166 1167 if ((s->s3->handshake_fragment[1] != 0) || 1168 (s->s3->handshake_fragment[2] != 0) || 1169 (s->s3->handshake_fragment[3] != 0)) 1170 { 1171 al=SSL_AD_DECODE_ERROR; 1172 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_BAD_HELLO_REQUEST); 1173 goto f_err; 1174 } 1175 1176 if (s->msg_callback) 1177 s->msg_callback(0, s->version, SSL3_RT_HANDSHAKE, s->s3->handshake_fragment, 4, s, s->msg_callback_arg); 1178 1179 if (SSL_is_init_finished(s) && 1180 !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS) && 1181 !s->s3->renegotiate) 1182 { 1183 ssl3_renegotiate(s); 1184 if (ssl3_renegotiate_check(s)) 1185 { 1186 i=s->handshake_func(s); 1187 if (i < 0) return(i); 1188 if (i == 0) 1189 { 1190 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE); 1191 return(-1); 1192 } 1193 1194 if (!(s->mode & SSL_MODE_AUTO_RETRY)) 1195 { 1196 if (s->s3->rbuf.left == 0) /* no read-ahead left? */ 1197 { 1198 BIO *bio; 1199 /* In the case where we try to read application data, 1200 * but we trigger an SSL handshake, we return -1 with 1201 * the retry option set. Otherwise renegotiation may 1202 * cause nasty problems in the blocking world */ 1203 s->rwstate=SSL_READING; 1204 bio=SSL_get_rbio(s); 1205 BIO_clear_retry_flags(bio); 1206 BIO_set_retry_read(bio); 1207 return(-1); 1208 } 1209 } 1210 } 1211 } 1212 /* we either finished a handshake or ignored the request, 1213 * now try again to obtain the (application) data we were asked for */ 1214 goto start; 1215 } 1216 /* If we are a server and get a client hello when renegotiation isn't 1217 * allowed send back a no renegotiation alert and carry on. 1218 * WARNING: experimental code, needs reviewing (steve) 1219 */ 1220 if (s->server && 1221 SSL_is_init_finished(s) && 1222 !s->s3->send_connection_binding && 1223 (s->version > SSL3_VERSION) && 1224 (s->s3->handshake_fragment_len >= 4) && 1225 (s->s3->handshake_fragment[0] == SSL3_MT_CLIENT_HELLO) && 1226 (s->session != NULL) && (s->session->cipher != NULL) && 1227 !(s->ctx->options & SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION)) 1228 1229 { 1230 /*s->s3->handshake_fragment_len = 0;*/ 1231 rr->length = 0; 1232 ssl3_send_alert(s,SSL3_AL_WARNING, SSL_AD_NO_RENEGOTIATION); 1233 goto start; 1234 } 1235 if (s->s3->alert_fragment_len >= 2) 1236 { 1237 int alert_level = s->s3->alert_fragment[0]; 1238 int alert_descr = s->s3->alert_fragment[1]; 1239 1240 s->s3->alert_fragment_len = 0; 1241 1242 if (s->msg_callback) 1243 s->msg_callback(0, s->version, SSL3_RT_ALERT, s->s3->alert_fragment, 2, s, s->msg_callback_arg); 1244 1245 if (s->info_callback != NULL) 1246 cb=s->info_callback; 1247 else if (s->ctx->info_callback != NULL) 1248 cb=s->ctx->info_callback; 1249 1250 if (cb != NULL) 1251 { 1252 j = (alert_level << 8) | alert_descr; 1253 cb(s, SSL_CB_READ_ALERT, j); 1254 } 1255 1256 if (alert_level == 1) /* warning */ 1257 { 1258 s->s3->warn_alert = alert_descr; 1259 if (alert_descr == SSL_AD_CLOSE_NOTIFY) 1260 { 1261 s->shutdown |= SSL_RECEIVED_SHUTDOWN; 1262 return(0); 1263 } 1264 /* This is a warning but we receive it if we requested 1265 * renegotiation and the peer denied it. Terminate with 1266 * a fatal alert because if application tried to 1267 * renegotiatie it presumably had a good reason and 1268 * expects it to succeed. 1269 * 1270 * In future we might have a renegotiation where we 1271 * don't care if the peer refused it where we carry on. 1272 */ 1273 else if (alert_descr == SSL_AD_NO_RENEGOTIATION) 1274 { 1275 al = SSL_AD_HANDSHAKE_FAILURE; 1276 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_NO_RENEGOTIATION); 1277 goto f_err; 1278 } 1279 #ifdef SSL_AD_MISSING_SRP_USERNAME 1280 if (alert_descr == SSL_AD_MISSING_SRP_USERNAME) 1281 return(0); 1282 #endif 1283 } 1284 else if (alert_level == 2) /* fatal */ 1285 { 1286 char tmp[16]; 1287 1288 s->rwstate=SSL_NOTHING; 1289 s->s3->fatal_alert = alert_descr; 1290 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_AD_REASON_OFFSET + alert_descr); 1291 BIO_snprintf(tmp,sizeof tmp,"%d",alert_descr); 1292 ERR_add_error_data(2,"SSL alert number ",tmp); 1293 s->shutdown|=SSL_RECEIVED_SHUTDOWN; 1294 SSL_CTX_remove_session(s->ctx,s->session); 1295 return(0); 1296 } 1297 else 1298 { 1299 al=SSL_AD_ILLEGAL_PARAMETER; 1300 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNKNOWN_ALERT_TYPE); 1301 goto f_err; 1302 } 1303 1304 goto start; 1305 } 1306 1307 if (s->shutdown & SSL_SENT_SHUTDOWN) /* but we have not received a shutdown */ 1308 { 1309 s->rwstate=SSL_NOTHING; 1310 rr->length=0; 1311 return(0); 1312 } 1313 1314 if (rr->type == SSL3_RT_CHANGE_CIPHER_SPEC) 1315 { 1316 /* 'Change Cipher Spec' is just a single byte, so we know 1317 * exactly what the record payload has to look like */ 1318 if ( (rr->length != 1) || (rr->off != 0) || 1319 (rr->data[0] != SSL3_MT_CCS)) 1320 { 1321 al=SSL_AD_ILLEGAL_PARAMETER; 1322 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_BAD_CHANGE_CIPHER_SPEC); 1323 goto f_err; 1324 } 1325 1326 /* Check we have a cipher to change to */ 1327 if (s->s3->tmp.new_cipher == NULL) 1328 { 1329 al=SSL_AD_UNEXPECTED_MESSAGE; 1330 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_CCS_RECEIVED_EARLY); 1331 goto f_err; 1332 } 1333 1334 rr->length=0; 1335 1336 if (s->msg_callback) 1337 s->msg_callback(0, s->version, SSL3_RT_CHANGE_CIPHER_SPEC, rr->data, 1, s, s->msg_callback_arg); 1338 1339 s->s3->change_cipher_spec=1; 1340 if (!ssl3_do_change_cipher_spec(s)) 1341 goto err; 1342 else 1343 goto start; 1344 } 1345 1346 /* Unexpected handshake message (Client Hello, or protocol violation) */ 1347 if ((s->s3->handshake_fragment_len >= 4) && !s->in_handshake) 1348 { 1349 if (((s->state&SSL_ST_MASK) == SSL_ST_OK) && 1350 !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS)) 1351 { 1352 #if 0 /* worked only because C operator preferences are not as expected (and 1353 * because this is not really needed for clients except for detecting 1354 * protocol violations): */ 1355 s->state=SSL_ST_BEFORE|(s->server) 1356 ?SSL_ST_ACCEPT 1357 :SSL_ST_CONNECT; 1358 #else 1359 s->state = s->server ? SSL_ST_ACCEPT : SSL_ST_CONNECT; 1360 #endif 1361 s->renegotiate=1; 1362 s->new_session=1; 1363 } 1364 i=s->handshake_func(s); 1365 if (i < 0) return(i); 1366 if (i == 0) 1367 { 1368 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE); 1369 return(-1); 1370 } 1371 1372 if (!(s->mode & SSL_MODE_AUTO_RETRY)) 1373 { 1374 if (s->s3->rbuf.left == 0) /* no read-ahead left? */ 1375 { 1376 BIO *bio; 1377 /* In the case where we try to read application data, 1378 * but we trigger an SSL handshake, we return -1 with 1379 * the retry option set. Otherwise renegotiation may 1380 * cause nasty problems in the blocking world */ 1381 s->rwstate=SSL_READING; 1382 bio=SSL_get_rbio(s); 1383 BIO_clear_retry_flags(bio); 1384 BIO_set_retry_read(bio); 1385 return(-1); 1386 } 1387 } 1388 goto start; 1389 } 1390 1391 switch (rr->type) 1392 { 1393 default: 1394 #ifndef OPENSSL_NO_TLS 1395 /* TLS up to v1.1 just ignores unknown message types: 1396 * TLS v1.2 give an unexpected message alert. 1397 */ 1398 if (s->version >= TLS1_VERSION && s->version <= TLS1_1_VERSION) 1399 { 1400 rr->length = 0; 1401 goto start; 1402 } 1403 #endif 1404 al=SSL_AD_UNEXPECTED_MESSAGE; 1405 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNEXPECTED_RECORD); 1406 goto f_err; 1407 case SSL3_RT_CHANGE_CIPHER_SPEC: 1408 case SSL3_RT_ALERT: 1409 case SSL3_RT_HANDSHAKE: 1410 /* we already handled all of these, with the possible exception 1411 * of SSL3_RT_HANDSHAKE when s->in_handshake is set, but that 1412 * should not happen when type != rr->type */ 1413 al=SSL_AD_UNEXPECTED_MESSAGE; 1414 SSLerr(SSL_F_SSL3_READ_BYTES,ERR_R_INTERNAL_ERROR); 1415 goto f_err; 1416 case SSL3_RT_APPLICATION_DATA: 1417 /* At this point, we were expecting handshake data, 1418 * but have application data. If the library was 1419 * running inside ssl3_read() (i.e. in_read_app_data 1420 * is set) and it makes sense to read application data 1421 * at this point (session renegotiation not yet started), 1422 * we will indulge it. 1423 */ 1424 if (s->s3->in_read_app_data && 1425 (s->s3->total_renegotiations != 0) && 1426 (( 1427 (s->state & SSL_ST_CONNECT) && 1428 (s->state >= SSL3_ST_CW_CLNT_HELLO_A) && 1429 (s->state <= SSL3_ST_CR_SRVR_HELLO_A) 1430 ) || ( 1431 (s->state & SSL_ST_ACCEPT) && 1432 (s->state <= SSL3_ST_SW_HELLO_REQ_A) && 1433 (s->state >= SSL3_ST_SR_CLNT_HELLO_A) 1434 ) 1435 )) 1436 { 1437 s->s3->in_read_app_data=2; 1438 return(-1); 1439 } 1440 else 1441 { 1442 al=SSL_AD_UNEXPECTED_MESSAGE; 1443 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNEXPECTED_RECORD); 1444 goto f_err; 1445 } 1446 } 1447 /* not reached */ 1448 1449 f_err: 1450 ssl3_send_alert(s,SSL3_AL_FATAL,al); 1451 err: 1452 return(-1); 1453 } 1454 1455 int ssl3_do_change_cipher_spec(SSL *s) 1456 { 1457 int i; 1458 const char *sender; 1459 int slen; 1460 1461 if (s->state & SSL_ST_ACCEPT) 1462 i=SSL3_CHANGE_CIPHER_SERVER_READ; 1463 else 1464 i=SSL3_CHANGE_CIPHER_CLIENT_READ; 1465 1466 if (s->s3->tmp.key_block == NULL) 1467 { 1468 if (s->session == NULL) 1469 { 1470 /* might happen if dtls1_read_bytes() calls this */ 1471 SSLerr(SSL_F_SSL3_DO_CHANGE_CIPHER_SPEC,SSL_R_CCS_RECEIVED_EARLY); 1472 return (0); 1473 } 1474 1475 s->session->cipher=s->s3->tmp.new_cipher; 1476 if (!s->method->ssl3_enc->setup_key_block(s)) return(0); 1477 } 1478 1479 if (!s->method->ssl3_enc->change_cipher_state(s,i)) 1480 return(0); 1481 1482 /* we have to record the message digest at 1483 * this point so we can get it before we read 1484 * the finished message */ 1485 if (s->state & SSL_ST_CONNECT) 1486 { 1487 sender=s->method->ssl3_enc->server_finished_label; 1488 slen=s->method->ssl3_enc->server_finished_label_len; 1489 } 1490 else 1491 { 1492 sender=s->method->ssl3_enc->client_finished_label; 1493 slen=s->method->ssl3_enc->client_finished_label_len; 1494 } 1495 1496 s->s3->tmp.peer_finish_md_len = s->method->ssl3_enc->final_finish_mac(s, 1497 sender,slen,s->s3->tmp.peer_finish_md); 1498 1499 return(1); 1500 } 1501 1502 int ssl3_send_alert(SSL *s, int level, int desc) 1503 { 1504 /* Map tls/ssl alert value to correct one */ 1505 desc=s->method->ssl3_enc->alert_value(desc); 1506 if (s->version == SSL3_VERSION && desc == SSL_AD_PROTOCOL_VERSION) 1507 desc = SSL_AD_HANDSHAKE_FAILURE; /* SSL 3.0 does not have protocol_version alerts */ 1508 if (desc < 0) return -1; 1509 /* If a fatal one, remove from cache */ 1510 if ((level == 2) && (s->session != NULL)) 1511 SSL_CTX_remove_session(s->ctx,s->session); 1512 1513 s->s3->alert_dispatch=1; 1514 s->s3->send_alert[0]=level; 1515 s->s3->send_alert[1]=desc; 1516 if (s->s3->wbuf.left == 0) /* data still being written out? */ 1517 return s->method->ssl_dispatch_alert(s); 1518 /* else data is still being written out, we will get written 1519 * some time in the future */ 1520 return -1; 1521 } 1522 1523 int ssl3_dispatch_alert(SSL *s) 1524 { 1525 int i,j; 1526 void (*cb)(const SSL *ssl,int type,int val)=NULL; 1527 1528 s->s3->alert_dispatch=0; 1529 i = do_ssl3_write(s, SSL3_RT_ALERT, &s->s3->send_alert[0], 2, 0); 1530 if (i <= 0) 1531 { 1532 s->s3->alert_dispatch=1; 1533 } 1534 else 1535 { 1536 /* Alert sent to BIO. If it is important, flush it now. 1537 * If the message does not get sent due to non-blocking IO, 1538 * we will not worry too much. */ 1539 if (s->s3->send_alert[0] == SSL3_AL_FATAL) 1540 (void)BIO_flush(s->wbio); 1541 1542 if (s->msg_callback) 1543 s->msg_callback(1, s->version, SSL3_RT_ALERT, s->s3->send_alert, 2, s, s->msg_callback_arg); 1544 1545 if (s->info_callback != NULL) 1546 cb=s->info_callback; 1547 else if (s->ctx->info_callback != NULL) 1548 cb=s->ctx->info_callback; 1549 1550 if (cb != NULL) 1551 { 1552 j=(s->s3->send_alert[0]<<8)|s->s3->send_alert[1]; 1553 cb(s,SSL_CB_WRITE_ALERT,j); 1554 } 1555 } 1556 return(i); 1557 } 1558
