1 /* ssl/s3_pkt.c */
2 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
3 * All rights reserved.
4 *
5 * This package is an SSL implementation written
6 * by Eric Young (eay@cryptsoft.com).
7 * The implementation was written so as to conform with Netscapes SSL.
8 *
9 * This library is free for commercial and non-commercial use as long as
10 * the following conditions are aheared to. The following conditions
11 * apply to all code found in this distribution, be it the RC4, RSA,
12 * lhash, DES, etc., code; not just the SSL code. The SSL documentation
13 * included with this distribution is covered by the same copyright terms
14 * except that the holder is Tim Hudson (tjh@cryptsoft.com).
15 *
16 * Copyright remains Eric Young's, and as such any Copyright notices in
17 * the code are not to be removed.
18 * If this package is used in a product, Eric Young should be given attribution
19 * as the author of the parts of the library used.
20 * This can be in the form of a textual message at program startup or
21 * in documentation (online or textual) provided with the package.
22 *
23 * Redistribution and use in source and binary forms, with or without
24 * modification, are permitted provided that the following conditions
25 * are met:
26 * 1. Redistributions of source code must retain the copyright
27 * notice, this list of conditions and the following disclaimer.
28 * 2. Redistributions in binary form must reproduce the above copyright
29 * notice, this list of conditions and the following disclaimer in the
30 * documentation and/or other materials provided with the distribution.
31 * 3. All advertising materials mentioning features or use of this software
32 * must display the following acknowledgement:
33 * "This product includes cryptographic software written by
34 * Eric Young (eay@cryptsoft.com)"
35 * The word 'cryptographic' can be left out if the rouines from the library
36 * being used are not cryptographic related :-).
37 * 4. If you include any Windows specific code (or a derivative thereof) from
38 * the apps directory (application code) you must include an acknowledgement:
39 * "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
40 *
41 * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
42 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
43 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
44 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
45 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
46 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
47 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
48 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
49 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
50 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
51 * SUCH DAMAGE.
52 *
53 * The licence and distribution terms for any publically available version or
54 * derivative of this code cannot be changed. i.e. this code cannot simply be
55 * copied and put under another distribution licence
56 * [including the GNU Public Licence.]
57 */
58 /* ====================================================================
59 * Copyright (c) 1998-2002 The OpenSSL Project. All rights reserved.
60 *
61 * Redistribution and use in source and binary forms, with or without
62 * modification, are permitted provided that the following conditions
63 * are met:
64 *
65 * 1. Redistributions of source code must retain the above copyright
66 * notice, this list of conditions and the following disclaimer.
67 *
68 * 2. Redistributions in binary form must reproduce the above copyright
69 * notice, this list of conditions and the following disclaimer in
70 * the documentation and/or other materials provided with the
71 * distribution.
72 *
73 * 3. All advertising materials mentioning features or use of this
74 * software must display the following acknowledgment:
75 * "This product includes software developed by the OpenSSL Project
76 * for use in the OpenSSL Toolkit. (http://www.openssl.org/)"
77 *
78 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
79 * endorse or promote products derived from this software without
80 * prior written permission. For written permission, please contact
81 * openssl-core@openssl.org.
82 *
83 * 5. Products derived from this software may not be called "OpenSSL"
84 * nor may "OpenSSL" appear in their names without prior written
85 * permission of the OpenSSL Project.
86 *
87 * 6. Redistributions of any form whatsoever must retain the following
88 * acknowledgment:
89 * "This product includes software developed by the OpenSSL Project
90 * for use in the OpenSSL Toolkit (http://www.openssl.org/)"
91 *
92 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
93 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
94 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
95 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR
96 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
97 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
98 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
99 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
100 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
101 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
102 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
103 * OF THE POSSIBILITY OF SUCH DAMAGE.
104 * ====================================================================
105 *
106 * This product includes cryptographic software written by Eric Young
107 * (eay@cryptsoft.com). This product includes software written by Tim
108 * Hudson (tjh@cryptsoft.com).
109 *
110 */
111
112 #include <stdio.h>
113 #include <limits.h>
114 #include <errno.h>
115 #define USE_SOCKETS
116 #include "ssl_locl.h"
117 #include <openssl/evp.h>
118 #include <openssl/buffer.h>
119 #include <openssl/rand.h>
120
121 static int do_ssl3_write(SSL *s, int type, const unsigned char *buf,
122 unsigned int len, int create_empty_fragment);
123 static int ssl3_get_record(SSL *s);
124
125 int ssl3_read_n(SSL *s, int n, int max, int extend)
126 {
127 /* If extend == 0, obtain new n-byte packet; if extend == 1, increase
128 * packet by another n bytes.
129 * The packet will be in the sub-array of s->s3->rbuf.buf specified
130 * by s->packet and s->packet_length.
131 * (If s->read_ahead is set, 'max' bytes may be stored in rbuf
132 * [plus s->packet_length bytes if extend == 1].)
133 */
134 int i,len,left;
135 long align=0;
136 unsigned char *pkt;
137 SSL3_BUFFER *rb;
138
139 if (n <= 0) return n;
140
141 rb = &(s->s3->rbuf);
142 if (rb->buf == NULL)
143 if (!ssl3_setup_read_buffer(s))
144 return -1;
145
146 left = rb->left;
147 #if defined(SSL3_ALIGN_PAYLOAD) && SSL3_ALIGN_PAYLOAD!=0
148 align = (long)rb->buf + SSL3_RT_HEADER_LENGTH;
149 align = (-align)&(SSL3_ALIGN_PAYLOAD-1);
150 #endif
151
152 if (!extend)
153 {
154 /* start with empty packet ... */
155 if (left == 0)
156 rb->offset = align;
157 else if (align != 0 && left >= SSL3_RT_HEADER_LENGTH)
158 {
159 /* check if next packet length is large
160 * enough to justify payload alignment... */
161 pkt = rb->buf + rb->offset;
162 if (pkt[0] == SSL3_RT_APPLICATION_DATA
163 && (pkt[3]<<8|pkt[4]) >= 128)
164 {
165 /* Note that even if packet is corrupted
166 * and its length field is insane, we can
167 * only be led to wrong decision about
168 * whether memmove will occur or not.
169 * Header values has no effect on memmove
170 * arguments and therefore no buffer
171 * overrun can be triggered. */
172 memmove (rb->buf+align,pkt,left);
173 rb->offset = align;
174 }
175 }
176 s->packet = rb->buf + rb->offset;
177 s->packet_length = 0;
178 /* ... now we can act as if 'extend' was set */
179 }
180
181 /* For DTLS/UDP reads should not span multiple packets
182 * because the read operation returns the whole packet
183 * at once (as long as it fits into the buffer). */
184 if (SSL_version(s) == DTLS1_VERSION || SSL_version(s) == DTLS1_BAD_VER)
185 {
186 if (left > 0 && n > left)
187 n = left;
188 }
189
190 /* if there is enough in the buffer from a previous read, take some */
191 if (left >= n)
192 {
193 s->packet_length+=n;
194 rb->left=left-n;
195 rb->offset+=n;
196 return(n);
197 }
198
199 /* else we need to read more data */
200
201 len = s->packet_length;
202 pkt = rb->buf+align;
203 /* Move any available bytes to front of buffer:
204 * 'len' bytes already pointed to by 'packet',
205 * 'left' extra ones at the end */
206 if (s->packet != pkt) /* len > 0 */
207 {
208 memmove(pkt, s->packet, len+left);
209 s->packet = pkt;
210 rb->offset = len + align;
211 }
212
213 if (n > (int)(rb->len - rb->offset)) /* does not happen */
214 {
215 SSLerr(SSL_F_SSL3_READ_N,ERR_R_INTERNAL_ERROR);
216 return -1;
217 }
218
219 if (!s->read_ahead)
220 /* ignore max parameter */
221 max = n;
222 else
223 {
224 if (max < n)
225 max = n;
226 if (max > (int)(rb->len - rb->offset))
227 max = rb->len - rb->offset;
228 }
229
230 while (left < n)
231 {
232 /* Now we have len+left bytes at the front of s->s3->rbuf.buf
233 * and need to read in more until we have len+n (up to
234 * len+max if possible) */
235
236 clear_sys_error();
237 if (s->rbio != NULL)
238 {
239 s->rwstate=SSL_READING;
240 i=BIO_read(s->rbio,pkt+len+left, max-left);
241 }
242 else
243 {
244 SSLerr(SSL_F_SSL3_READ_N,SSL_R_READ_BIO_NOT_SET);
245 i = -1;
246 }
247
248 if (i <= 0)
249 {
250 rb->left = left;
251 if (s->mode & SSL_MODE_RELEASE_BUFFERS &&
252 SSL_version(s) != DTLS1_VERSION && SSL_version(s) != DTLS1_BAD_VER)
253 if (len+left == 0)
254 ssl3_release_read_buffer(s);
255 return(i);
256 }
257 left+=i;
258 /* reads should *never* span multiple packets for DTLS because
259 * the underlying transport protocol is message oriented as opposed
260 * to byte oriented as in the TLS case. */
261 if (SSL_version(s) == DTLS1_VERSION || SSL_version(s) == DTLS1_BAD_VER)
262 {
263 if (n > left)
264 n = left; /* makes the while condition false */
265 }
266 }
267
268 /* done reading, now the book-keeping */
269 rb->offset += n;
270 rb->left = left - n;
271 s->packet_length += n;
272 s->rwstate=SSL_NOTHING;
273 return(n);
274 }
275
276 /* Call this to get a new input record.
277 * It will return <= 0 if more data is needed, normally due to an error
278 * or non-blocking IO.
279 * When it finishes, one packet has been decoded and can be found in
280 * ssl->s3->rrec.type - is the type of record
281 * ssl->s3->rrec.data, - data
282 * ssl->s3->rrec.length, - number of bytes
283 */
284 /* used only by ssl3_read_bytes */
285 static int ssl3_get_record(SSL *s)
286 {
287 int ssl_major,ssl_minor,al;
288 int enc_err,n,i,ret= -1;
289 SSL3_RECORD *rr;
290 SSL_SESSION *sess;
291 unsigned char *p;
292 unsigned char md[EVP_MAX_MD_SIZE];
293 short version;
294 unsigned mac_size, orig_len;
295 size_t extra;
296
297 rr= &(s->s3->rrec);
298 sess=s->session;
299
300 if (s->options & SSL_OP_MICROSOFT_BIG_SSLV3_BUFFER)
301 extra=SSL3_RT_MAX_EXTRA;
302 else
303 extra=0;
304 if (extra && !s->s3->init_extra)
305 {
306 /* An application error: SLS_OP_MICROSOFT_BIG_SSLV3_BUFFER
307 * set after ssl3_setup_buffers() was done */
308 SSLerr(SSL_F_SSL3_GET_RECORD, ERR_R_INTERNAL_ERROR);
309 return -1;
310 }
311
312 again:
313 /* check if we have the header */
314 if ( (s->rstate != SSL_ST_READ_BODY) ||
315 (s->packet_length < SSL3_RT_HEADER_LENGTH))
316 {
317 n=ssl3_read_n(s, SSL3_RT_HEADER_LENGTH, s->s3->rbuf.len, 0);
318 if (n <= 0) return(n); /* error or non-blocking */
319 s->rstate=SSL_ST_READ_BODY;
320
321 p=s->packet;
322
323 /* Pull apart the header into the SSL3_RECORD */
324 rr->type= *(p++);
325 ssl_major= *(p++);
326 ssl_minor= *(p++);
327 version=(ssl_major<<8)|ssl_minor;
328 n2s(p,rr->length);
329 #if 0
330 fprintf(stderr, "Record type=%d, Length=%d\n", rr->type, rr->length);
331 #endif
332
333 /* Lets check version */
334 if (!s->first_packet)
335 {
336 if (version != s->version)
337 {
338 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_WRONG_VERSION_NUMBER);
339 if ((s->version & 0xFF00) == (version & 0xFF00) && !s->enc_write_ctx && !s->write_hash)
340 /* Send back error using their minor version number :-) */
341 s->version = (unsigned short)version;
342 al=SSL_AD_PROTOCOL_VERSION;
343 goto f_err;
344 }
345 }
346
347 if ((version>>8) != SSL3_VERSION_MAJOR)
348 {
349 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_WRONG_VERSION_NUMBER);
350 goto err;
351 }
352
353 if (rr->length > s->s3->rbuf.len - SSL3_RT_HEADER_LENGTH)
354 {
355 al=SSL_AD_RECORD_OVERFLOW;
356 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_PACKET_LENGTH_TOO_LONG);
357 goto f_err;
358 }
359
360 /* now s->rstate == SSL_ST_READ_BODY */
361 }
362
363 /* s->rstate == SSL_ST_READ_BODY, get and decode the data */
364
365 if (rr->length > s->packet_length-SSL3_RT_HEADER_LENGTH)
366 {
367 /* now s->packet_length == SSL3_RT_HEADER_LENGTH */
368 i=rr->length;
369 n=ssl3_read_n(s,i,i,1);
370 if (n <= 0) return(n); /* error or non-blocking io */
371 /* now n == rr->length,
372 * and s->packet_length == SSL3_RT_HEADER_LENGTH + rr->length */
373 }
374
375 s->rstate=SSL_ST_READ_HEADER; /* set state for later operations */
376
377 /* At this point, s->packet_length == SSL3_RT_HEADER_LNGTH + rr->length,
378 * and we have that many bytes in s->packet
379 */
380 rr->input= &(s->packet[SSL3_RT_HEADER_LENGTH]);
381
382 /* ok, we can now read from 's->packet' data into 'rr'
383 * rr->input points at rr->length bytes, which
384 * need to be copied into rr->data by either
385 * the decryption or by the decompression
386 * When the data is 'copied' into the rr->data buffer,
387 * rr->input will be pointed at the new buffer */
388
389 /* We now have - encrypted [ MAC [ compressed [ plain ] ] ]
390 * rr->length bytes of encrypted compressed stuff. */
391
392 /* check is not needed I believe */
393 if (rr->length > SSL3_RT_MAX_ENCRYPTED_LENGTH+extra)
394 {
395 al=SSL_AD_RECORD_OVERFLOW;
396 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_ENCRYPTED_LENGTH_TOO_LONG);
397 goto f_err;
398 }
399
400 /* decrypt in place in 'rr->input' */
401 rr->data=rr->input;
402
403 enc_err = s->method->ssl3_enc->enc(s,0);
404 /* enc_err is:
405 * 0: (in non-constant time) if the record is publically invalid.
406 * 1: if the padding is valid
407 * -1: if the padding is invalid */
408 if (enc_err == 0)
409 {
410 al=SSL_AD_DECRYPTION_FAILED;
411 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_BLOCK_CIPHER_PAD_IS_WRONG);
412 goto f_err;
413 }
414
415 #ifdef TLS_DEBUG
416 printf("dec %d\n",rr->length);
417 { unsigned int z; for (z=0; z<rr->length; z++) printf("%02X%c",rr->data[z],((z+1)%16)?' ':'\n'); }
418 printf("\n");
419 #endif
420
421 /* r->length is now the compressed data plus mac */
422 if ((sess != NULL) &&
423 (s->enc_read_ctx != NULL) &&
424 (EVP_MD_CTX_md(s->read_hash) != NULL))
425 {
426 /* s->read_hash != NULL => mac_size != -1 */
427 unsigned char *mac = NULL;
428 unsigned char mac_tmp[EVP_MAX_MD_SIZE];
429 mac_size=EVP_MD_CTX_size(s->read_hash);
430 OPENSSL_assert(mac_size <= EVP_MAX_MD_SIZE);
431
432 /* kludge: *_cbc_remove_padding passes padding length in rr->type */
433 orig_len = rr->length+((unsigned int)rr->type>>8);
434
435 /* orig_len is the length of the record before any padding was
436 * removed. This is public information, as is the MAC in use,
437 * therefore we can safely process the record in a different
438 * amount of time if it's too short to possibly contain a MAC.
439 */
440 if (orig_len < mac_size ||
441 /* CBC records must have a padding length byte too. */
442 (EVP_CIPHER_CTX_mode(s->enc_read_ctx) == EVP_CIPH_CBC_MODE &&
443 orig_len < mac_size+1))
444 {
445 al=SSL_AD_DECODE_ERROR;
446 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_LENGTH_TOO_SHORT);
447 goto f_err;
448 }
449
450 if (EVP_CIPHER_CTX_mode(s->enc_read_ctx) == EVP_CIPH_CBC_MODE)
451 {
452 /* We update the length so that the TLS header bytes
453 * can be constructed correctly but we need to extract
454 * the MAC in constant time from within the record,
455 * without leaking the contents of the padding bytes.
456 * */
457 mac = mac_tmp;
458 ssl3_cbc_copy_mac(mac_tmp, rr, mac_size, orig_len);
459 rr->length -= mac_size;
460 }
461 else
462 {
463 /* In this case there's no padding, so |orig_len|
464 * equals |rec->length| and we checked that there's
465 * enough bytes for |mac_size| above. */
466 rr->length -= mac_size;
467 mac = &rr->data[rr->length];
468 }
469
470 i=s->method->ssl3_enc->mac(s,md,0 /* not send */);
471 if (i < 0 || mac == NULL || CRYPTO_memcmp(md, mac, (size_t)mac_size) != 0)
472 enc_err = -1;
473 if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH+extra+mac_size)
474 enc_err = -1;
475 }
476
477 if (enc_err < 0)
478 {
479 /* A separate 'decryption_failed' alert was introduced with TLS 1.0,
480 * SSL 3.0 only has 'bad_record_mac'. But unless a decryption
481 * failure is directly visible from the ciphertext anyway,
482 * we should not reveal which kind of error occured -- this
483 * might become visible to an attacker (e.g. via a logfile) */
484 al=SSL_AD_BAD_RECORD_MAC;
485 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_DECRYPTION_FAILED_OR_BAD_RECORD_MAC);
486 goto f_err;
487 }
488
489 /* r->length is now just compressed */
490 if (s->expand != NULL)
491 {
492 if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH+extra)
493 {
494 al=SSL_AD_RECORD_OVERFLOW;
495 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_COMPRESSED_LENGTH_TOO_LONG);
496 goto f_err;
497 }
498 if (!ssl3_do_uncompress(s))
499 {
500 al=SSL_AD_DECOMPRESSION_FAILURE;
501 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_BAD_DECOMPRESSION);
502 goto f_err;
503 }
504 }
505
506 if (rr->length > SSL3_RT_MAX_PLAIN_LENGTH+extra)
507 {
508 al=SSL_AD_RECORD_OVERFLOW;
509 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_DATA_LENGTH_TOO_LONG);
510 goto f_err;
511 }
512
513 rr->off=0;
514 /* So at this point the following is true
515 * ssl->s3->rrec.type is the type of record
516 * ssl->s3->rrec.length == number of bytes in record
517 * ssl->s3->rrec.off == offset to first valid byte
518 * ssl->s3->rrec.data == where to take bytes from, increment
519 * after use :-).
520 */
521
522 /* we have pulled in a full packet so zero things */
523 s->packet_length=0;
524
525 /* just read a 0 length packet */
526 if (rr->length == 0) goto again;
527
528 #if 0
529 fprintf(stderr, "Ultimate Record type=%d, Length=%d\n", rr->type, rr->length);
530 #endif
531
532 return(1);
533
534 f_err:
535 ssl3_send_alert(s,SSL3_AL_FATAL,al);
536 err:
537 return(ret);
538 }
539
540 int ssl3_do_uncompress(SSL *ssl)
541 {
542 #ifndef OPENSSL_NO_COMP
543 int i;
544 SSL3_RECORD *rr;
545
546 rr= &(ssl->s3->rrec);
547 i=COMP_expand_block(ssl->expand,rr->comp,
548 SSL3_RT_MAX_PLAIN_LENGTH,rr->data,(int)rr->length);
549 if (i < 0)
550 return(0);
551 else
552 rr->length=i;
553 rr->data=rr->comp;
554 #endif
555 return(1);
556 }
557
558 int ssl3_do_compress(SSL *ssl)
559 {
560 #ifndef OPENSSL_NO_COMP
561 int i;
562 SSL3_RECORD *wr;
563
564 wr= &(ssl->s3->wrec);
565 i=COMP_compress_block(ssl->compress,wr->data,
566 SSL3_RT_MAX_COMPRESSED_LENGTH,
567 wr->input,(int)wr->length);
568 if (i < 0)
569 return(0);
570 else
571 wr->length=i;
572
573 wr->input=wr->data;
574 #endif
575 return(1);
576 }
577
578 /* Call this to write data in records of type 'type'
579 * It will return <= 0 if not all data has been sent or non-blocking IO.
580 */
581 int ssl3_write_bytes(SSL *s, int type, const void *buf_, int len)
582 {
583 const unsigned char *buf=buf_;
584 unsigned int n,nw;
585 int i,tot;
586
587 s->rwstate=SSL_NOTHING;
588 OPENSSL_assert(s->s3->wnum <= INT_MAX);
589 tot=s->s3->wnum;
590 s->s3->wnum=0;
591
592 if (SSL_in_init(s) && !s->in_handshake)
593 {
594 i=s->handshake_func(s);
595 if (i < 0) return(i);
596 if (i == 0)
597 {
598 SSLerr(SSL_F_SSL3_WRITE_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
599 return -1;
600 }
601 }
602
603 /* ensure that if we end up with a smaller value of data to write
604 * out than the the original len from a write which didn't complete
605 * for non-blocking I/O and also somehow ended up avoiding
606 * the check for this in ssl3_write_pending/SSL_R_BAD_WRITE_RETRY as
607 * it must never be possible to end up with (len-tot) as a large
608 * number that will then promptly send beyond the end of the users
609 * buffer ... so we trap and report the error in a way the user
610 * will notice
611 */
612 if (len < tot)
613 {
614 SSLerr(SSL_F_SSL3_WRITE_BYTES,SSL_R_BAD_LENGTH);
615 return(-1);
616 }
617
618
619 n=(len-tot);
620 for (;;)
621 {
622 if (n > s->max_send_fragment)
623 nw=s->max_send_fragment;
624 else
625 nw=n;
626
627 i=do_ssl3_write(s, type, &(buf[tot]), nw, 0);
628 if (i <= 0)
629 {
630 s->s3->wnum=tot;
631 return i;
632 }
633
634 if ((i == (int)n) ||
635 (type == SSL3_RT_APPLICATION_DATA &&
636 (s->mode & SSL_MODE_ENABLE_PARTIAL_WRITE)))
637 {
638 /* next chunk of data should get another prepended empty fragment
639 * in ciphersuites with known-IV weakness: */
640 s->s3->empty_fragment_done = 0;
641
642 return tot+i;
643 }
644
645 n-=i;
646 tot+=i;
647 }
648 }
649
650 static int do_ssl3_write(SSL *s, int type, const unsigned char *buf,
651 unsigned int len, int create_empty_fragment)
652 {
653 unsigned char *p,*plen;
654 int i,mac_size,clear=0;
655 int prefix_len=0;
656 int eivlen;
657 long align=0;
658 SSL3_RECORD *wr;
659 SSL3_BUFFER *wb=&(s->s3->wbuf);
660 SSL_SESSION *sess;
661
662
663 /* first check if there is a SSL3_BUFFER still being written
664 * out. This will happen with non blocking IO */
665 if (wb->left != 0)
666 return(ssl3_write_pending(s,type,buf,len));
667
668 /* If we have an alert to send, lets send it */
669 if (s->s3->alert_dispatch)
670 {
671 i=s->method->ssl_dispatch_alert(s);
672 if (i <= 0)
673 return(i);
674 /* if it went, fall through and send more stuff */
675 }
676
677 if (wb->buf == NULL)
678 if (!ssl3_setup_write_buffer(s))
679 return -1;
680
681 if (len == 0 && !create_empty_fragment)
682 return 0;
683
684 wr= &(s->s3->wrec);
685 sess=s->session;
686
687 if ( (sess == NULL) ||
688 (s->enc_write_ctx == NULL) ||
689 (EVP_MD_CTX_md(s->write_hash) == NULL))
690 {
691 #if 1
692 clear=s->enc_write_ctx?0:1; /* must be AEAD cipher */
693 #else
694 clear=1;
695 #endif
696 mac_size=0;
697 }
698 else
699 {
700 mac_size=EVP_MD_CTX_size(s->write_hash);
701 if (mac_size < 0)
702 goto err;
703 }
704
705 /* 'create_empty_fragment' is true only when this function calls itself */
706 if (!clear && !create_empty_fragment && !s->s3->empty_fragment_done)
707 {
708 /* countermeasure against known-IV weakness in CBC ciphersuites
709 * (see http://www.openssl.org/~bodo/tls-cbc.txt) */
710
711 if (s->s3->need_empty_fragments && type == SSL3_RT_APPLICATION_DATA)
712 {
713 /* recursive function call with 'create_empty_fragment' set;
714 * this prepares and buffers the data for an empty fragment
715 * (these 'prefix_len' bytes are sent out later
716 * together with the actual payload) */
717 prefix_len = do_ssl3_write(s, type, buf, 0, 1);
718 if (prefix_len <= 0)
719 goto err;
720
721 if (prefix_len >
722 (SSL3_RT_HEADER_LENGTH + SSL3_RT_SEND_MAX_ENCRYPTED_OVERHEAD))
723 {
724 /* insufficient space */
725 SSLerr(SSL_F_DO_SSL3_WRITE, ERR_R_INTERNAL_ERROR);
726 goto err;
727 }
728 }
729
730 s->s3->empty_fragment_done = 1;
731 }
732
733 if (create_empty_fragment)
734 {
735 #if defined(SSL3_ALIGN_PAYLOAD) && SSL3_ALIGN_PAYLOAD!=0
736 /* extra fragment would be couple of cipher blocks,
737 * which would be multiple of SSL3_ALIGN_PAYLOAD, so
738 * if we want to align the real payload, then we can
739 * just pretent we simply have two headers. */
740 align = (long)wb->buf + 2*SSL3_RT_HEADER_LENGTH;
741 align = (-align)&(SSL3_ALIGN_PAYLOAD-1);
742 #endif
743 p = wb->buf + align;
744 wb->offset = align;
745 }
746 else if (prefix_len)
747 {
748 p = wb->buf + wb->offset + prefix_len;
749 }
750 else
751 {
752 #if defined(SSL3_ALIGN_PAYLOAD) && SSL3_ALIGN_PAYLOAD!=0
753 align = (long)wb->buf + SSL3_RT_HEADER_LENGTH;
754 align = (-align)&(SSL3_ALIGN_PAYLOAD-1);
755 #endif
756 p = wb->buf + align;
757 wb->offset = align;
758 }
759
760 /* write the header */
761
762 *(p++)=type&0xff;
763 wr->type=type;
764
765 *(p++)=(s->version>>8);
766 /* Some servers hang if iniatial client hello is larger than 256
767 * bytes and record version number > TLS 1.0
768 */
769 if (s->state == SSL3_ST_CW_CLNT_HELLO_B
770 && !s->renegotiate
771 && TLS1_get_version(s) > TLS1_VERSION)
772 *(p++) = 0x1;
773 else
774 *(p++)=s->version&0xff;
775
776 /* field where we are to write out packet length */
777 plen=p;
778 p+=2;
779 /* Explicit IV length, block ciphers and TLS version 1.1 or later */
780 if (s->enc_write_ctx && s->version >= TLS1_1_VERSION)
781 {
782 int mode = EVP_CIPHER_CTX_mode(s->enc_write_ctx);
783 if (mode == EVP_CIPH_CBC_MODE)
784 {
785 eivlen = EVP_CIPHER_CTX_iv_length(s->enc_write_ctx);
786 if (eivlen <= 1)
787 eivlen = 0;
788 }
789 /* Need explicit part of IV for GCM mode */
790 else if (mode == EVP_CIPH_GCM_MODE)
791 eivlen = EVP_GCM_TLS_EXPLICIT_IV_LEN;
792 else
793 eivlen = 0;
794 }
795 else
796 eivlen = 0;
797
798 /* lets setup the record stuff. */
799 wr->data=p + eivlen;
800 wr->length=(int)len;
801 wr->input=(unsigned char *)buf;
802
803 /* we now 'read' from wr->input, wr->length bytes into
804 * wr->data */
805
806 /* first we compress */
807 if (s->compress != NULL)
808 {
809 if (!ssl3_do_compress(s))
810 {
811 SSLerr(SSL_F_DO_SSL3_WRITE,SSL_R_COMPRESSION_FAILURE);
812 goto err;
813 }
814 }
815 else
816 {
817 memcpy(wr->data,wr->input,wr->length);
818 wr->input=wr->data;
819 }
820
821 /* we should still have the output to wr->data and the input
822 * from wr->input. Length should be wr->length.
823 * wr->data still points in the wb->buf */
824
825 if (mac_size != 0)
826 {
827 if (s->method->ssl3_enc->mac(s,&(p[wr->length + eivlen]),1) < 0)
828 goto err;
829 wr->length+=mac_size;
830 }
831
832 wr->input=p;
833 wr->data=p;
834
835 if (eivlen)
836 {
837 /* if (RAND_pseudo_bytes(p, eivlen) <= 0)
838 goto err; */
839 wr->length += eivlen;
840 }
841
842 /* ssl3_enc can only have an error on read */
843 s->method->ssl3_enc->enc(s,1);
844
845 /* record length after mac and block padding */
846 s2n(wr->length,plen);
847
848 /* we should now have
849 * wr->data pointing to the encrypted data, which is
850 * wr->length long */
851 wr->type=type; /* not needed but helps for debugging */
852 wr->length+=SSL3_RT_HEADER_LENGTH;
853
854 if (create_empty_fragment)
855 {
856 /* we are in a recursive call;
857 * just return the length, don't write out anything here
858 */
859 return wr->length;
860 }
861
862 /* now let's set up wb */
863 wb->left = prefix_len + wr->length;
864
865 /* memorize arguments so that ssl3_write_pending can detect bad write retries later */
866 s->s3->wpend_tot=len;
867 s->s3->wpend_buf=buf;
868 s->s3->wpend_type=type;
869 s->s3->wpend_ret=len;
870
871 /* we now just need to write the buffer */
872 return ssl3_write_pending(s,type,buf,len);
873 err:
874 return -1;
875 }
876
877 /* if s->s3->wbuf.left != 0, we need to call this */
878 int ssl3_write_pending(SSL *s, int type, const unsigned char *buf,
879 unsigned int len)
880 {
881 int i;
882 SSL3_BUFFER *wb=&(s->s3->wbuf);
883
884 /* XXXX */
885 if ((s->s3->wpend_tot > (int)len)
886 || ((s->s3->wpend_buf != buf) &&
887 !(s->mode & SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER))
888 || (s->s3->wpend_type != type))
889 {
890 SSLerr(SSL_F_SSL3_WRITE_PENDING,SSL_R_BAD_WRITE_RETRY);
891 return(-1);
892 }
893
894 for (;;)
895 {
896 clear_sys_error();
897 if (s->wbio != NULL)
898 {
899 s->rwstate=SSL_WRITING;
900 i=BIO_write(s->wbio,
901 (char *)&(wb->buf[wb->offset]),
902 (unsigned int)wb->left);
903 }
904 else
905 {
906 SSLerr(SSL_F_SSL3_WRITE_PENDING,SSL_R_BIO_NOT_SET);
907 i= -1;
908 }
909 if (i == wb->left)
910 {
911 wb->left=0;
912 wb->offset+=i;
913 if (s->mode & SSL_MODE_RELEASE_BUFFERS &&
914 SSL_version(s) != DTLS1_VERSION && SSL_version(s) != DTLS1_BAD_VER)
915 ssl3_release_write_buffer(s);
916 s->rwstate=SSL_NOTHING;
917 return(s->s3->wpend_ret);
918 }
919 else if (i <= 0) {
920 if (s->version == DTLS1_VERSION ||
921 s->version == DTLS1_BAD_VER) {
922 /* For DTLS, just drop it. That's kind of the whole
923 point in using a datagram service */
924 wb->left = 0;
925 }
926 return(i);
927 }
928 wb->offset+=i;
929 wb->left-=i;
930 }
931 }
932
933 /* Return up to 'len' payload bytes received in 'type' records.
934 * 'type' is one of the following:
935 *
936 * - SSL3_RT_HANDSHAKE (when ssl3_get_message calls us)
937 * - SSL3_RT_APPLICATION_DATA (when ssl3_read calls us)
938 * - 0 (during a shutdown, no data has to be returned)
939 *
940 * If we don't have stored data to work from, read a SSL/TLS record first
941 * (possibly multiple records if we still don't have anything to return).
942 *
943 * This function must handle any surprises the peer may have for us, such as
944 * Alert records (e.g. close_notify), ChangeCipherSpec records (not really
945 * a surprise, but handled as if it were), or renegotiation requests.
946 * Also if record payloads contain fragments too small to process, we store
947 * them until there is enough for the respective protocol (the record protocol
948 * may use arbitrary fragmentation and even interleaving):
949 * Change cipher spec protocol
950 * just 1 byte needed, no need for keeping anything stored
951 * Alert protocol
952 * 2 bytes needed (AlertLevel, AlertDescription)
953 * Handshake protocol
954 * 4 bytes needed (HandshakeType, uint24 length) -- we just have
955 * to detect unexpected Client Hello and Hello Request messages
956 * here, anything else is handled by higher layers
957 * Application data protocol
958 * none of our business
959 */
960 int ssl3_read_bytes(SSL *s, int type, unsigned char *buf, int len, int peek)
961 {
962 int al,i,j,ret;
963 unsigned int n;
964 SSL3_RECORD *rr;
965 void (*cb)(const SSL *ssl,int type2,int val)=NULL;
966
967 if (s->s3->rbuf.buf == NULL) /* Not initialized yet */
968 if (!ssl3_setup_read_buffer(s))
969 return(-1);
970
971 if ((type && (type != SSL3_RT_APPLICATION_DATA) && (type != SSL3_RT_HANDSHAKE)) ||
972 (peek && (type != SSL3_RT_APPLICATION_DATA)))
973 {
974 SSLerr(SSL_F_SSL3_READ_BYTES, ERR_R_INTERNAL_ERROR);
975 return -1;
976 }
977
978 if ((type == SSL3_RT_HANDSHAKE) && (s->s3->handshake_fragment_len > 0))
979 /* (partially) satisfy request from storage */
980 {
981 unsigned char *src = s->s3->handshake_fragment;
982 unsigned char *dst = buf;
983 unsigned int k;
984
985 /* peek == 0 */
986 n = 0;
987 while ((len > 0) && (s->s3->handshake_fragment_len > 0))
988 {
989 *dst++ = *src++;
990 len--; s->s3->handshake_fragment_len--;
991 n++;
992 }
993 /* move any remaining fragment bytes: */
994 for (k = 0; k < s->s3->handshake_fragment_len; k++)
995 s->s3->handshake_fragment[k] = *src++;
996 return n;
997 }
998
999 /* Now s->s3->handshake_fragment_len == 0 if type == SSL3_RT_HANDSHAKE. */
1000
1001 if (!s->in_handshake && SSL_in_init(s))
1002 {
1003 /* type == SSL3_RT_APPLICATION_DATA */
1004 i=s->handshake_func(s);
1005 if (i < 0) return(i);
1006 if (i == 0)
1007 {
1008 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
1009 return(-1);
1010 }
1011 }
1012 start:
1013 s->rwstate=SSL_NOTHING;
1014
1015 /* s->s3->rrec.type - is the type of record
1016 * s->s3->rrec.data, - data
1017 * s->s3->rrec.off, - offset into 'data' for next read
1018 * s->s3->rrec.length, - number of bytes. */
1019 rr = &(s->s3->rrec);
1020
1021 /* get new packet if necessary */
1022 if ((rr->length == 0) || (s->rstate == SSL_ST_READ_BODY))
1023 {
1024 ret=ssl3_get_record(s);
1025 if (ret <= 0) return(ret);
1026 }
1027
1028 /* we now have a packet which can be read and processed */
1029
1030 if (s->s3->change_cipher_spec /* set when we receive ChangeCipherSpec,
1031 * reset by ssl3_get_finished */
1032 && (rr->type != SSL3_RT_HANDSHAKE))
1033 {
1034 al=SSL_AD_UNEXPECTED_MESSAGE;
1035 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_DATA_BETWEEN_CCS_AND_FINISHED);
1036 goto f_err;
1037 }
1038
1039 /* If the other end has shut down, throw anything we read away
1040 * (even in 'peek' mode) */
1041 if (s->shutdown & SSL_RECEIVED_SHUTDOWN)
1042 {
1043 rr->length=0;
1044 s->rwstate=SSL_NOTHING;
1045 return(0);
1046 }
1047
1048
1049 if (type == rr->type) /* SSL3_RT_APPLICATION_DATA or SSL3_RT_HANDSHAKE */
1050 {
1051 /* make sure that we are not getting application data when we
1052 * are doing a handshake for the first time */
1053 if (SSL_in_init(s) && (type == SSL3_RT_APPLICATION_DATA) &&
1054 (s->enc_read_ctx == NULL))
1055 {
1056 al=SSL_AD_UNEXPECTED_MESSAGE;
1057 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_APP_DATA_IN_HANDSHAKE);
1058 goto f_err;
1059 }
1060
1061 if (len <= 0) return(len);
1062
1063 if ((unsigned int)len > rr->length)
1064 n = rr->length;
1065 else
1066 n = (unsigned int)len;
1067
1068 memcpy(buf,&(rr->data[rr->off]),n);
1069 if (!peek)
1070 {
1071 rr->length-=n;
1072 rr->off+=n;
1073 if (rr->length == 0)
1074 {
1075 s->rstate=SSL_ST_READ_HEADER;
1076 rr->off=0;
1077 if (s->mode & SSL_MODE_RELEASE_BUFFERS && s->s3->rbuf.left == 0)
1078 ssl3_release_read_buffer(s);
1079 }
1080 }
1081 return(n);
1082 }
1083
1084
1085 /* If we get here, then type != rr->type; if we have a handshake
1086 * message, then it was unexpected (Hello Request or Client Hello). */
1087
1088 /* In case of record types for which we have 'fragment' storage,
1089 * fill that so that we can process the data at a fixed place.
1090 */
1091 {
1092 unsigned int dest_maxlen = 0;
1093 unsigned char *dest = NULL;
1094 unsigned int *dest_len = NULL;
1095
1096 if (rr->type == SSL3_RT_HANDSHAKE)
1097 {
1098 dest_maxlen = sizeof s->s3->handshake_fragment;
1099 dest = s->s3->handshake_fragment;
1100 dest_len = &s->s3->handshake_fragment_len;
1101 }
1102 else if (rr->type == SSL3_RT_ALERT)
1103 {
1104 dest_maxlen = sizeof s->s3->alert_fragment;
1105 dest = s->s3->alert_fragment;
1106 dest_len = &s->s3->alert_fragment_len;
1107 }
1108 #ifndef OPENSSL_NO_HEARTBEATS
1109 else if (rr->type == TLS1_RT_HEARTBEAT)
1110 {
1111 tls1_process_heartbeat(s);
1112
1113 /* Exit and notify application to read again */
1114 rr->length = 0;
1115 s->rwstate=SSL_READING;
1116 BIO_clear_retry_flags(SSL_get_rbio(s));
1117 BIO_set_retry_read(SSL_get_rbio(s));
1118 return(-1);
1119 }
1120 #endif
1121
1122 if (dest_maxlen > 0)
1123 {
1124 n = dest_maxlen - *dest_len; /* available space in 'dest' */
1125 if (rr->length < n)
1126 n = rr->length; /* available bytes */
1127
1128 /* now move 'n' bytes: */
1129 while (n-- > 0)
1130 {
1131 dest[(*dest_len)++] = rr->data[rr->off++];
1132 rr->length--;
1133 }
1134
1135 if (*dest_len < dest_maxlen)
1136 goto start; /* fragment was too small */
1137 }
1138 }
1139
1140 /* s->s3->handshake_fragment_len == 4 iff rr->type == SSL3_RT_HANDSHAKE;
1141 * s->s3->alert_fragment_len == 2 iff rr->type == SSL3_RT_ALERT.
1142 * (Possibly rr is 'empty' now, i.e. rr->length may be 0.) */
1143
1144 /* If we are a client, check for an incoming 'Hello Request': */
1145 if ((!s->server) &&
1146 (s->s3->handshake_fragment_len >= 4) &&
1147 (s->s3->handshake_fragment[0] == SSL3_MT_HELLO_REQUEST) &&
1148 (s->session != NULL) && (s->session->cipher != NULL))
1149 {
1150 s->s3->handshake_fragment_len = 0;
1151
1152 if ((s->s3->handshake_fragment[1] != 0) ||
1153 (s->s3->handshake_fragment[2] != 0) ||
1154 (s->s3->handshake_fragment[3] != 0))
1155 {
1156 al=SSL_AD_DECODE_ERROR;
1157 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_BAD_HELLO_REQUEST);
1158 goto f_err;
1159 }
1160
1161 if (s->msg_callback)
1162 s->msg_callback(0, s->version, SSL3_RT_HANDSHAKE, s->s3->handshake_fragment, 4, s, s->msg_callback_arg);
1163
1164 if (SSL_is_init_finished(s) &&
1165 !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS) &&
1166 !s->s3->renegotiate)
1167 {
1168 ssl3_renegotiate(s);
1169 if (ssl3_renegotiate_check(s))
1170 {
1171 i=s->handshake_func(s);
1172 if (i < 0) return(i);
1173 if (i == 0)
1174 {
1175 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
1176 return(-1);
1177 }
1178
1179 if (!(s->mode & SSL_MODE_AUTO_RETRY))
1180 {
1181 if (s->s3->rbuf.left == 0) /* no read-ahead left? */
1182 {
1183 BIO *bio;
1184 /* In the case where we try to read application data,
1185 * but we trigger an SSL handshake, we return -1 with
1186 * the retry option set. Otherwise renegotiation may
1187 * cause nasty problems in the blocking world */
1188 s->rwstate=SSL_READING;
1189 bio=SSL_get_rbio(s);
1190 BIO_clear_retry_flags(bio);
1191 BIO_set_retry_read(bio);
1192 return(-1);
1193 }
1194 }
1195 }
1196 }
1197 /* we either finished a handshake or ignored the request,
1198 * now try again to obtain the (application) data we were asked for */
1199 goto start;
1200 }
1201 /* If we are a server and get a client hello when renegotiation isn't
1202 * allowed send back a no renegotiation alert and carry on.
1203 * WARNING: experimental code, needs reviewing (steve)
1204 */
1205 if (s->server &&
1206 SSL_is_init_finished(s) &&
1207 !s->s3->send_connection_binding &&
1208 (s->version > SSL3_VERSION) &&
1209 (s->s3->handshake_fragment_len >= 4) &&
1210 (s->s3->handshake_fragment[0] == SSL3_MT_CLIENT_HELLO) &&
1211 (s->session != NULL) && (s->session->cipher != NULL) &&
1212 !(s->ctx->options & SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION))
1213
1214 {
1215 /*s->s3->handshake_fragment_len = 0;*/
1216 rr->length = 0;
1217 ssl3_send_alert(s,SSL3_AL_WARNING, SSL_AD_NO_RENEGOTIATION);
1218 goto start;
1219 }
1220 if (s->s3->alert_fragment_len >= 2)
1221 {
1222 int alert_level = s->s3->alert_fragment[0];
1223 int alert_descr = s->s3->alert_fragment[1];
1224
1225 s->s3->alert_fragment_len = 0;
1226
1227 if (s->msg_callback)
1228 s->msg_callback(0, s->version, SSL3_RT_ALERT, s->s3->alert_fragment, 2, s, s->msg_callback_arg);
1229
1230 if (s->info_callback != NULL)
1231 cb=s->info_callback;
1232 else if (s->ctx->info_callback != NULL)
1233 cb=s->ctx->info_callback;
1234
1235 if (cb != NULL)
1236 {
1237 j = (alert_level << 8) | alert_descr;
1238 cb(s, SSL_CB_READ_ALERT, j);
1239 }
1240
1241 if (alert_level == 1) /* warning */
1242 {
1243 s->s3->warn_alert = alert_descr;
1244 if (alert_descr == SSL_AD_CLOSE_NOTIFY)
1245 {
1246 s->shutdown |= SSL_RECEIVED_SHUTDOWN;
1247 return(0);
1248 }
1249 /* This is a warning but we receive it if we requested
1250 * renegotiation and the peer denied it. Terminate with
1251 * a fatal alert because if application tried to
1252 * renegotiatie it presumably had a good reason and
1253 * expects it to succeed.
1254 *
1255 * In future we might have a renegotiation where we
1256 * don't care if the peer refused it where we carry on.
1257 */
1258 else if (alert_descr == SSL_AD_NO_RENEGOTIATION)
1259 {
1260 al = SSL_AD_HANDSHAKE_FAILURE;
1261 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_NO_RENEGOTIATION);
1262 goto f_err;
1263 }
1264 #ifdef SSL_AD_MISSING_SRP_USERNAME
1265 else if (alert_descr == SSL_AD_MISSING_SRP_USERNAME)
1266 return(0);
1267 #endif
1268 }
1269 else if (alert_level == 2) /* fatal */
1270 {
1271 char tmp[16];
1272
1273 s->rwstate=SSL_NOTHING;
1274 s->s3->fatal_alert = alert_descr;
1275 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_AD_REASON_OFFSET + alert_descr);
1276 BIO_snprintf(tmp,sizeof tmp,"%d",alert_descr);
1277 ERR_add_error_data(2,"SSL alert number ",tmp);
1278 s->shutdown|=SSL_RECEIVED_SHUTDOWN;
1279 SSL_CTX_remove_session(s->ctx,s->session);
1280 return(0);
1281 }
1282 else
1283 {
1284 al=SSL_AD_ILLEGAL_PARAMETER;
1285 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNKNOWN_ALERT_TYPE);
1286 goto f_err;
1287 }
1288
1289 goto start;
1290 }
1291
1292 if (s->shutdown & SSL_SENT_SHUTDOWN) /* but we have not received a shutdown */
1293 {
1294 s->rwstate=SSL_NOTHING;
1295 rr->length=0;
1296 return(0);
1297 }
1298
1299 if (rr->type == SSL3_RT_CHANGE_CIPHER_SPEC)
1300 {
1301 /* 'Change Cipher Spec' is just a single byte, so we know
1302 * exactly what the record payload has to look like */
1303 if ( (rr->length != 1) || (rr->off != 0) ||
1304 (rr->data[0] != SSL3_MT_CCS))
1305 {
1306 al=SSL_AD_ILLEGAL_PARAMETER;
1307 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_BAD_CHANGE_CIPHER_SPEC);
1308 goto f_err;
1309 }
1310
1311 /* Check we have a cipher to change to */
1312 if (s->s3->tmp.new_cipher == NULL)
1313 {
1314 al=SSL_AD_UNEXPECTED_MESSAGE;
1315 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_CCS_RECEIVED_EARLY);
1316 goto f_err;
1317 }
1318
1319 if (!(s->s3->flags & SSL3_FLAGS_CCS_OK))
1320 {
1321 al=SSL_AD_UNEXPECTED_MESSAGE;
1322 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_CCS_RECEIVED_EARLY);
1323 goto f_err;
1324 }
1325
1326 s->s3->flags &= ~SSL3_FLAGS_CCS_OK;
1327
1328 rr->length=0;
1329
1330 if (s->msg_callback)
1331 s->msg_callback(0, s->version, SSL3_RT_CHANGE_CIPHER_SPEC, rr->data, 1, s, s->msg_callback_arg);
1332
1333 s->s3->change_cipher_spec=1;
1334 if (!ssl3_do_change_cipher_spec(s))
1335 goto err;
1336 else
1337 goto start;
1338 }
1339
1340 /* Unexpected handshake message (Client Hello, or protocol violation) */
1341 if ((s->s3->handshake_fragment_len >= 4) && !s->in_handshake)
1342 {
1343 if (((s->state&SSL_ST_MASK) == SSL_ST_OK) &&
1344 !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS))
1345 {
1346 #if 0 /* worked only because C operator preferences are not as expected (and
1347 * because this is not really needed for clients except for detecting
1348 * protocol violations): */
1349 s->state=SSL_ST_BEFORE|(s->server)
1350 ?SSL_ST_ACCEPT
1351 :SSL_ST_CONNECT;
1352 #else
1353 s->state = s->server ? SSL_ST_ACCEPT : SSL_ST_CONNECT;
1354 #endif
1355 s->renegotiate=1;
1356 s->new_session=1;
1357 }
1358 i=s->handshake_func(s);
1359 if (i < 0) return(i);
1360 if (i == 0)
1361 {
1362 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
1363 return(-1);
1364 }
1365
1366 if (!(s->mode & SSL_MODE_AUTO_RETRY))
1367 {
1368 if (s->s3->rbuf.left == 0) /* no read-ahead left? */
1369 {
1370 BIO *bio;
1371 /* In the case where we try to read application data,
1372 * but we trigger an SSL handshake, we return -1 with
1373 * the retry option set. Otherwise renegotiation may
1374 * cause nasty problems in the blocking world */
1375 s->rwstate=SSL_READING;
1376 bio=SSL_get_rbio(s);
1377 BIO_clear_retry_flags(bio);
1378 BIO_set_retry_read(bio);
1379 return(-1);
1380 }
1381 }
1382 goto start;
1383 }
1384
1385 switch (rr->type)
1386 {
1387 default:
1388 #ifndef OPENSSL_NO_TLS
1389 /* TLS up to v1.1 just ignores unknown message types:
1390 * TLS v1.2 give an unexpected message alert.
1391 */
1392 if (s->version >= TLS1_VERSION && s->version <= TLS1_1_VERSION)
1393 {
1394 rr->length = 0;
1395 goto start;
1396 }
1397 #endif
1398 al=SSL_AD_UNEXPECTED_MESSAGE;
1399 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNEXPECTED_RECORD);
1400 goto f_err;
1401 case SSL3_RT_CHANGE_CIPHER_SPEC:
1402 case SSL3_RT_ALERT:
1403 case SSL3_RT_HANDSHAKE:
1404 /* we already handled all of these, with the possible exception
1405 * of SSL3_RT_HANDSHAKE when s->in_handshake is set, but that
1406 * should not happen when type != rr->type */
1407 al=SSL_AD_UNEXPECTED_MESSAGE;
1408 SSLerr(SSL_F_SSL3_READ_BYTES,ERR_R_INTERNAL_ERROR);
1409 goto f_err;
1410 case SSL3_RT_APPLICATION_DATA:
1411 /* At this point, we were expecting handshake data,
1412 * but have application data. If the library was
1413 * running inside ssl3_read() (i.e. in_read_app_data
1414 * is set) and it makes sense to read application data
1415 * at this point (session renegotiation not yet started),
1416 * we will indulge it.
1417 */
1418 if (s->s3->in_read_app_data &&
1419 (s->s3->total_renegotiations != 0) &&
1420 ((
1421 (s->state & SSL_ST_CONNECT) &&
1422 (s->state >= SSL3_ST_CW_CLNT_HELLO_A) &&
1423 (s->state <= SSL3_ST_CR_SRVR_HELLO_A)
1424 ) || (
1425 (s->state & SSL_ST_ACCEPT) &&
1426 (s->state <= SSL3_ST_SW_HELLO_REQ_A) &&
1427 (s->state >= SSL3_ST_SR_CLNT_HELLO_A)
1428 )
1429 ))
1430 {
1431 s->s3->in_read_app_data=2;
1432 return(-1);
1433 }
1434 else
1435 {
1436 al=SSL_AD_UNEXPECTED_MESSAGE;
1437 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNEXPECTED_RECORD);
1438 goto f_err;
1439 }
1440 }
1441 /* not reached */
1442
1443 f_err:
1444 ssl3_send_alert(s,SSL3_AL_FATAL,al);
1445 err:
1446 return(-1);
1447 }
1448
1449 int ssl3_do_change_cipher_spec(SSL *s)
1450 {
1451 int i;
1452 const char *sender;
1453 int slen;
1454
1455 if (s->state & SSL_ST_ACCEPT)
1456 i=SSL3_CHANGE_CIPHER_SERVER_READ;
1457 else
1458 i=SSL3_CHANGE_CIPHER_CLIENT_READ;
1459
1460 if (s->s3->tmp.key_block == NULL)
1461 {
1462 if (s->session == NULL || s->session->master_key_length == 0)
1463 {
1464 /* might happen if dtls1_read_bytes() calls this */
1465 SSLerr(SSL_F_SSL3_DO_CHANGE_CIPHER_SPEC,SSL_R_CCS_RECEIVED_EARLY);
1466 return (0);
1467 }
1468
1469 s->session->cipher=s->s3->tmp.new_cipher;
1470 if (!s->method->ssl3_enc->setup_key_block(s)) return(0);
1471 }
1472
1473 if (!s->method->ssl3_enc->change_cipher_state(s,i))
1474 return(0);
1475
1476 /* we have to record the message digest at
1477 * this point so we can get it before we read
1478 * the finished message */
1479 if (s->state & SSL_ST_CONNECT)
1480 {
1481 sender=s->method->ssl3_enc->server_finished_label;
1482 slen=s->method->ssl3_enc->server_finished_label_len;
1483 }
1484 else
1485 {
1486 sender=s->method->ssl3_enc->client_finished_label;
1487 slen=s->method->ssl3_enc->client_finished_label_len;
1488 }
1489
1490 i = s->method->ssl3_enc->final_finish_mac(s,
1491 sender,slen,s->s3->tmp.peer_finish_md);
1492 if (i == 0)
1493 {
1494 SSLerr(SSL_F_SSL3_DO_CHANGE_CIPHER_SPEC, ERR_R_INTERNAL_ERROR);
1495 return 0;
1496 }
1497 s->s3->tmp.peer_finish_md_len = i;
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 }