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1 /* ssl/s3_pkt.c */
2 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
3 * All rights reserved.
4 *
5 * This package is an SSL implementation written
6 * by Eric Young (eay@cryptsoft.com).
7 * The implementation was written so as to conform with Netscapes SSL.
8 *
9 * This library is free for commercial and non-commercial use as long as
10 * the following conditions are aheared to. The following conditions
11 * apply to all code found in this distribution, be it the RC4, RSA,
12 * lhash, DES, etc., code; not just the SSL code. The SSL documentation
13 * included with this distribution is covered by the same copyright terms
14 * except that the holder is Tim Hudson (tjh@cryptsoft.com).
15 *
16 * Copyright remains Eric Young's, and as such any Copyright notices in
17 * the code are not to be removed.
18 * If this package is used in a product, Eric Young should be given attribution
19 * as the author of the parts of the library used.
20 * This can be in the form of a textual message at program startup or
21 * in documentation (online or textual) provided with the package.
22 *
23 * Redistribution and use in source and binary forms, with or without
24 * modification, are permitted provided that the following conditions
25 * are met:
26 * 1. Redistributions of source code must retain the copyright
27 * notice, this list of conditions and the following disclaimer.
28 * 2. Redistributions in binary form must reproduce the above copyright
29 * notice, this list of conditions and the following disclaimer in the
30 * documentation and/or other materials provided with the distribution.
31 * 3. All advertising materials mentioning features or use of this software
32 * must display the following acknowledgement:
33 * "This product includes cryptographic software written by
34 * Eric Young (eay@cryptsoft.com)"
35 * The word 'cryptographic' can be left out if the rouines from the library
36 * being used are not cryptographic related :-).
37 * 4. If you include any Windows specific code (or a derivative thereof) from
38 * the apps directory (application code) you must include an acknowledgement:
39 * "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
40 *
41 * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
42 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
43 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
44 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
45 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
46 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
47 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
48 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
49 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
50 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
51 * SUCH DAMAGE.
52 *
53 * The licence and distribution terms for any publically available version or
54 * derivative of this code cannot be changed. i.e. this code cannot simply be
55 * copied and put under another distribution licence
56 * [including the GNU Public Licence.]
57 */
58 /* ====================================================================
59 * Copyright (c) 1998-2002 The OpenSSL Project. All rights reserved.
60 *
61 * Redistribution and use in source and binary forms, with or without
62 * modification, are permitted provided that the following conditions
63 * are met:
64 *
65 * 1. Redistributions of source code must retain the above copyright
66 * notice, this list of conditions and the following disclaimer.
67 *
68 * 2. Redistributions in binary form must reproduce the above copyright
69 * notice, this list of conditions and the following disclaimer in
70 * the documentation and/or other materials provided with the
71 * distribution.
72 *
73 * 3. All advertising materials mentioning features or use of this
74 * software must display the following acknowledgment:
75 * "This product includes software developed by the OpenSSL Project
76 * for use in the OpenSSL Toolkit. (http://www.openssl.org/)"
77 *
78 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
79 * endorse or promote products derived from this software without
80 * prior written permission. For written permission, please contact
81 * openssl-core@openssl.org.
82 *
83 * 5. Products derived from this software may not be called "OpenSSL"
84 * nor may "OpenSSL" appear in their names without prior written
85 * permission of the OpenSSL Project.
86 *
87 * 6. Redistributions of any form whatsoever must retain the following
88 * acknowledgment:
89 * "This product includes software developed by the OpenSSL Project
90 * for use in the OpenSSL Toolkit (http://www.openssl.org/)"
91 *
92 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
93 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
94 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
95 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR
96 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
97 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
98 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
99 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
100 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
101 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
102 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
103 * OF THE POSSIBILITY OF SUCH DAMAGE.
104 * ====================================================================
105 *
106 * This product includes cryptographic software written by Eric Young
107 * (eay@cryptsoft.com). This product includes software written by Tim
108 * Hudson (tjh@cryptsoft.com).
109 *
110 */
111
112 #include <stdio.h>
113 #include <errno.h>
114 #define USE_SOCKETS
115 #include "ssl_locl.h"
116 #include <openssl/evp.h>
117 #include <openssl/buffer.h>
118 #include <openssl/rand.h>
119
120 #ifndef EVP_CIPH_FLAG_TLS1_1_MULTIBLOCK
121 # define EVP_CIPH_FLAG_TLS1_1_MULTIBLOCK 0
122 #endif
123
124 static int do_ssl3_write(SSL *s, int type, const unsigned char *buf,
125 unsigned int len, int create_empty_fragment);
126 static int ssl3_get_record(SSL *s);
127
128 int ssl3_read_n(SSL *s, int n, int max, int extend)
129 {
130 /* If extend == 0, obtain new n-byte packet; if extend == 1, increase
131 * packet by another n bytes.
132 * The packet will be in the sub-array of s->s3->rbuf.buf specified
133 * by s->packet and s->packet_length.
134 * (If s->read_ahead is set, 'max' bytes may be stored in rbuf
135 * [plus s->packet_length bytes if extend == 1].)
136 */
137 int i,len,left;
138 long align=0;
139 unsigned char *pkt;
140 SSL3_BUFFER *rb;
141
142 if (n <= 0) return n;
143
144 rb = &(s->s3->rbuf);
145 if (rb->buf == NULL)
146 if (!ssl3_setup_read_buffer(s))
147 return -1;
148
149 left = rb->left;
150 #if defined(SSL3_ALIGN_PAYLOAD) && SSL3_ALIGN_PAYLOAD!=0
151 align = (long)rb->buf + SSL3_RT_HEADER_LENGTH;
152 align = (-align)&(SSL3_ALIGN_PAYLOAD-1);
153 #endif
154
155 if (!extend)
156 {
157 /* start with empty packet ... */
158 if (left == 0)
159 rb->offset = align;
160 else if (align != 0 && left >= SSL3_RT_HEADER_LENGTH)
161 {
162 /* check if next packet length is large
163 * enough to justify payload alignment... */
164 pkt = rb->buf + rb->offset;
165 if (pkt[0] == SSL3_RT_APPLICATION_DATA
166 && (pkt[3]<<8|pkt[4]) >= 128)
167 {
168 /* Note that even if packet is corrupted
169 * and its length field is insane, we can
170 * only be led to wrong decision about
171 * whether memmove will occur or not.
172 * Header values has no effect on memmove
173 * arguments and therefore no buffer
174 * overrun can be triggered. */
175 memmove (rb->buf+align,pkt,left);
176 rb->offset = align;
177 }
178 }
179 s->packet = rb->buf + rb->offset;
180 s->packet_length = 0;
181 /* ... now we can act as if 'extend' was set */
182 }
183
184 /* For DTLS/UDP reads should not span multiple packets
185 * because the read operation returns the whole packet
186 * at once (as long as it fits into the buffer). */
187 if (SSL_IS_DTLS(s))
188 {
189 if (left > 0 && n > left)
190 n = left;
191 }
192
193 /* if there is enough in the buffer from a previous read, take some */
194 if (left >= n)
195 {
196 s->packet_length+=n;
197 rb->left=left-n;
198 rb->offset+=n;
199 return(n);
200 }
201
202 /* else we need to read more data */
203
204 len = s->packet_length;
205 pkt = rb->buf+align;
206 /* Move any available bytes to front of buffer:
207 * 'len' bytes already pointed to by 'packet',
208 * 'left' extra ones at the end */
209 if (s->packet != pkt) /* len > 0 */
210 {
211 memmove(pkt, s->packet, len+left);
212 s->packet = pkt;
213 rb->offset = len + align;
214 }
215
216 if (n > (int)(rb->len - rb->offset)) /* does not happen */
217 {
218 SSLerr(SSL_F_SSL3_READ_N,ERR_R_INTERNAL_ERROR);
219 return -1;
220 }
221
222 if (!s->read_ahead)
223 /* ignore max parameter */
224 max = n;
225 else
226 {
227 if (max < n)
228 max = n;
229 if (max > (int)(rb->len - rb->offset))
230 max = rb->len - rb->offset;
231 }
232
233 while (left < n)
234 {
235 /* Now we have len+left bytes at the front of s->s3->rbuf.buf
236 * and need to read in more until we have len+n (up to
237 * len+max if possible) */
238
239 clear_sys_error();
240 if (s->rbio != NULL)
241 {
242 s->rwstate=SSL_READING;
243 i=BIO_read(s->rbio,pkt+len+left, max-left);
244 }
245 else
246 {
247 SSLerr(SSL_F_SSL3_READ_N,SSL_R_READ_BIO_NOT_SET);
248 i = -1;
249 }
250
251 if (i <= 0)
252 {
253 rb->left = left;
254 if (s->mode & SSL_MODE_RELEASE_BUFFERS &&
255 !SSL_IS_DTLS(s))
256 if (len+left == 0)
257 ssl3_release_read_buffer(s);
258 return(i);
259 }
260 left+=i;
261 /* reads should *never* span multiple packets for DTLS because
262 * the underlying transport protocol is message oriented as opposed
263 * to byte oriented as in the TLS case. */
264 if (SSL_IS_DTLS(s))
265 {
266 if (n > left)
267 n = left; /* makes the while condition false */
268 }
269 }
270
271 /* done reading, now the book-keeping */
272 rb->offset += n;
273 rb->left = left - n;
274 s->packet_length += n;
275 s->rwstate=SSL_NOTHING;
276 return(n);
277 }
278
279 /* MAX_EMPTY_RECORDS defines the number of consecutive, empty records that will
280 * be processed per call to ssl3_get_record. Without this limit an attacker
281 * could send empty records at a faster rate than we can process and cause
282 * ssl3_get_record to loop forever. */
283 #define MAX_EMPTY_RECORDS 32
284
285 /* Call this to get a new input record.
286 * It will return <= 0 if more data is needed, normally due to an error
287 * or non-blocking IO.
288 * When it finishes, one packet has been decoded and can be found in
289 * ssl->s3->rrec.type - is the type of record
290 * ssl->s3->rrec.data, - data
291 * ssl->s3->rrec.length, - number of bytes
292 */
293 /* used only by ssl3_read_bytes */
294 static int ssl3_get_record(SSL *s)
295 {
296 int ssl_major,ssl_minor,al;
297 int enc_err,n,i,ret= -1;
298 SSL3_RECORD *rr;
299 SSL_SESSION *sess;
300 unsigned char *p;
301 unsigned char md[EVP_MAX_MD_SIZE];
302 short version;
303 unsigned mac_size;
304 size_t extra;
305 unsigned empty_record_count = 0;
306
307 rr= &(s->s3->rrec);
308 sess=s->session;
309
310 if (s->options & SSL_OP_MICROSOFT_BIG_SSLV3_BUFFER)
311 extra=SSL3_RT_MAX_EXTRA;
312 else
313 extra=0;
314 if (extra && !s->s3->init_extra)
315 {
316 /* An application error: SLS_OP_MICROSOFT_BIG_SSLV3_BUFFER
317 * set after ssl3_setup_buffers() was done */
318 SSLerr(SSL_F_SSL3_GET_RECORD, ERR_R_INTERNAL_ERROR);
319 return -1;
320 }
321
322 again:
323 /* check if we have the header */
324 if ( (s->rstate != SSL_ST_READ_BODY) ||
325 (s->packet_length < SSL3_RT_HEADER_LENGTH))
326 {
327 n=ssl3_read_n(s, SSL3_RT_HEADER_LENGTH, s->s3->rbuf.len, 0);
328 if (n <= 0) return(n); /* error or non-blocking */
329 s->rstate=SSL_ST_READ_BODY;
330
331 p=s->packet;
332 if (s->msg_callback)
333 s->msg_callback(0, 0, SSL3_RT_HEADER, p, 5, s, s->msg_callback_arg);
334
335 /* Pull apart the header into the SSL3_RECORD */
336 rr->type= *(p++);
337 ssl_major= *(p++);
338 ssl_minor= *(p++);
339 version=(ssl_major<<8)|ssl_minor;
340 n2s(p,rr->length);
341 #if 0
342 fprintf(stderr, "Record type=%d, Length=%d\n", rr->type, rr->length);
343 #endif
344
345 /* Lets check version */
346 if (!s->first_packet)
347 {
348 if (version != s->version)
349 {
350 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_WRONG_VERSION_NUMBER);
351 if ((s->version & 0xFF00) == (version & 0xFF00) && !s->enc_write_ctx && !s->write_hash)
352 /* Send back error using their minor version number :-) */
353 s->version = (unsigned short)version;
354 al=SSL_AD_PROTOCOL_VERSION;
355 goto f_err;
356 }
357 }
358
359 if ((version>>8) != SSL3_VERSION_MAJOR)
360 {
361 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_WRONG_VERSION_NUMBER);
362 goto err;
363 }
364
365 if (rr->length > s->s3->rbuf.len - SSL3_RT_HEADER_LENGTH)
366 {
367 al=SSL_AD_RECORD_OVERFLOW;
368 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_PACKET_LENGTH_TOO_LONG);
369 goto f_err;
370 }
371
372 /* now s->rstate == SSL_ST_READ_BODY */
373 }
374
375 /* s->rstate == SSL_ST_READ_BODY, get and decode the data */
376
377 if (rr->length > s->packet_length-SSL3_RT_HEADER_LENGTH)
378 {
379 /* now s->packet_length == SSL3_RT_HEADER_LENGTH */
380 i=rr->length;
381 n=ssl3_read_n(s,i,i,1);
382 if (n <= 0) return(n); /* error or non-blocking io */
383 /* now n == rr->length,
384 * and s->packet_length == SSL3_RT_HEADER_LENGTH + rr->length */
385 }
386
387 s->rstate=SSL_ST_READ_HEADER; /* set state for later operations */
388
389 /* At this point, s->packet_length == SSL3_RT_HEADER_LNGTH + rr->length,
390 * and we have that many bytes in s->packet
391 */
392 rr->input= &(s->packet[SSL3_RT_HEADER_LENGTH]);
393
394 /* ok, we can now read from 's->packet' data into 'rr'
395 * rr->input points at rr->length bytes, which
396 * need to be copied into rr->data by either
397 * the decryption or by the decompression
398 * When the data is 'copied' into the rr->data buffer,
399 * rr->input will be pointed at the new buffer */
400
401 /* We now have - encrypted [ MAC [ compressed [ plain ] ] ]
402 * rr->length bytes of encrypted compressed stuff. */
403
404 /* check is not needed I believe */
405 if (rr->length > SSL3_RT_MAX_ENCRYPTED_LENGTH+extra)
406 {
407 al=SSL_AD_RECORD_OVERFLOW;
408 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_ENCRYPTED_LENGTH_TOO_LONG);
409 goto f_err;
410 }
411
412 /* decrypt in place in 'rr->input' */
413 rr->data=rr->input;
414 rr->orig_len=rr->length;
415 /* If in encrypt-then-mac mode calculate mac from encrypted record.
416 * All the details below are public so no timing details can leak.
417 */
418 if (SSL_USE_ETM(s) && s->read_hash)
419 {
420 unsigned char *mac;
421 mac_size=EVP_MD_CTX_size(s->read_hash);
422 OPENSSL_assert(mac_size <= EVP_MAX_MD_SIZE);
423 if (rr->length < mac_size)
424 {
425 al=SSL_AD_DECODE_ERROR;
426 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_LENGTH_TOO_SHORT);
427 goto f_err;
428 }
429 rr->length -= mac_size;
430 mac = rr->data + rr->length;
431 i=s->method->ssl3_enc->mac(s,md,0 /* not send */);
432 if (i < 0 || CRYPTO_memcmp(md, mac, (size_t)mac_size) != 0)
433 {
434 al=SSL_AD_BAD_RECORD_MAC;
435 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_DECRYPTION_FAILED_OR_BAD_RECORD_MAC);
436 goto f_err;
437 }
438 }
439
440 enc_err = s->method->ssl3_enc->enc(s,0);
441 /* enc_err is:
442 * 0: (in non-constant time) if the record is publically invalid.
443 * 1: if the padding is valid
444 * -1: if the padding is invalid */
445 if (enc_err == 0)
446 {
447 al=SSL_AD_DECRYPTION_FAILED;
448 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_BLOCK_CIPHER_PAD_IS_WRONG);
449 goto f_err;
450 }
451
452 #ifdef TLS_DEBUG
453 printf("dec %d\n",rr->length);
454 { unsigned int z; for (z=0; z<rr->length; z++) printf("%02X%c",rr->data[z],((z+1)%16)?' ':'\n'); }
455 printf("\n");
456 #endif
457
458 /* r->length is now the compressed data plus mac */
459 if ((sess != NULL) &&
460 (s->enc_read_ctx != NULL) &&
461 (EVP_MD_CTX_md(s->read_hash) != NULL) && !SSL_USE_ETM(s))
462 {
463 /* s->read_hash != NULL => mac_size != -1 */
464 unsigned char *mac = NULL;
465 unsigned char mac_tmp[EVP_MAX_MD_SIZE];
466 mac_size=EVP_MD_CTX_size(s->read_hash);
467 OPENSSL_assert(mac_size <= EVP_MAX_MD_SIZE);
468
469 /* orig_len is the length of the record before any padding was
470 * removed. This is public information, as is the MAC in use,
471 * therefore we can safely process the record in a different
472 * amount of time if it's too short to possibly contain a MAC.
473 */
474 if (rr->orig_len < mac_size ||
475 /* CBC records must have a padding length byte too. */
476 (EVP_CIPHER_CTX_mode(s->enc_read_ctx) == EVP_CIPH_CBC_MODE &&
477 rr->orig_len < mac_size+1))
478 {
479 al=SSL_AD_DECODE_ERROR;
480 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_LENGTH_TOO_SHORT);
481 goto f_err;
482 }
483
484 if (EVP_CIPHER_CTX_mode(s->enc_read_ctx) == EVP_CIPH_CBC_MODE)
485 {
486 /* We update the length so that the TLS header bytes
487 * can be constructed correctly but we need to extract
488 * the MAC in constant time from within the record,
489 * without leaking the contents of the padding bytes.
490 * */
491 mac = mac_tmp;
492 ssl3_cbc_copy_mac(mac_tmp, rr, mac_size);
493 rr->length -= mac_size;
494 }
495 else
496 {
497 /* In this case there's no padding, so |rec->orig_len|
498 * equals |rec->length| and we checked that there's
499 * enough bytes for |mac_size| above. */
500 rr->length -= mac_size;
501 mac = &rr->data[rr->length];
502 }
503
504 i=s->method->ssl3_enc->mac(s,md,0 /* not send */);
505 if (i < 0 || mac == NULL || CRYPTO_memcmp(md, mac, (size_t)mac_size) != 0)
506 enc_err = -1;
507 if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH+extra+mac_size)
508 enc_err = -1;
509 }
510
511 if (enc_err < 0)
512 {
513 /* A separate 'decryption_failed' alert was introduced with TLS 1.0,
514 * SSL 3.0 only has 'bad_record_mac'. But unless a decryption
515 * failure is directly visible from the ciphertext anyway,
516 * we should not reveal which kind of error occurred -- this
517 * might become visible to an attacker (e.g. via a logfile) */
518 al=SSL_AD_BAD_RECORD_MAC;
519 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_DECRYPTION_FAILED_OR_BAD_RECORD_MAC);
520 goto f_err;
521 }
522
523 /* r->length is now just compressed */
524 if (s->expand != NULL)
525 {
526 if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH+extra)
527 {
528 al=SSL_AD_RECORD_OVERFLOW;
529 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_COMPRESSED_LENGTH_TOO_LONG);
530 goto f_err;
531 }
532 if (!ssl3_do_uncompress(s))
533 {
534 al=SSL_AD_DECOMPRESSION_FAILURE;
535 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_BAD_DECOMPRESSION);
536 goto f_err;
537 }
538 }
539
540 if (rr->length > SSL3_RT_MAX_PLAIN_LENGTH+extra)
541 {
542 al=SSL_AD_RECORD_OVERFLOW;
543 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_DATA_LENGTH_TOO_LONG);
544 goto f_err;
545 }
546
547 rr->off=0;
548 /* So at this point the following is true
549 * ssl->s3->rrec.type is the type of record
550 * ssl->s3->rrec.length == number of bytes in record
551 * ssl->s3->rrec.off == offset to first valid byte
552 * ssl->s3->rrec.data == where to take bytes from, increment
553 * after use :-).
554 */
555
556 /* we have pulled in a full packet so zero things */
557 s->packet_length=0;
558
559 /* just read a 0 length packet */
560 if (rr->length == 0)
561 {
562 empty_record_count++;
563 if (empty_record_count > MAX_EMPTY_RECORDS)
564 {
565 al=SSL_AD_UNEXPECTED_MESSAGE;
566 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_TOO_MANY_EMPTY_FRAGMENTS);
567 goto f_err;
568 }
569 goto again;
570 }
571
572 #if 0
573 fprintf(stderr, "Ultimate Record type=%d, Length=%d\n", rr->type, rr->length);
574 #endif
575
576 return(1);
577
578 f_err:
579 ssl3_send_alert(s,SSL3_AL_FATAL,al);
580 err:
581 return(ret);
582 }
583
584 int ssl3_do_uncompress(SSL *ssl)
585 {
586 #ifndef OPENSSL_NO_COMP
587 int i;
588 SSL3_RECORD *rr;
589
590 rr= &(ssl->s3->rrec);
591 i=COMP_expand_block(ssl->expand,rr->comp,
592 SSL3_RT_MAX_PLAIN_LENGTH,rr->data,(int)rr->length);
593 if (i < 0)
594 return(0);
595 else
596 rr->length=i;
597 rr->data=rr->comp;
598 #endif
599 return(1);
600 }
601
602 int ssl3_do_compress(SSL *ssl)
603 {
604 #ifndef OPENSSL_NO_COMP
605 int i;
606 SSL3_RECORD *wr;
607
608 wr= &(ssl->s3->wrec);
609 i=COMP_compress_block(ssl->compress,wr->data,
610 SSL3_RT_MAX_COMPRESSED_LENGTH,
611 wr->input,(int)wr->length);
612 if (i < 0)
613 return(0);
614 else
615 wr->length=i;
616
617 wr->input=wr->data;
618 #endif
619 return(1);
620 }
621
622 /* Call this to write data in records of type 'type'
623 * It will return <= 0 if not all data has been sent or non-blocking IO.
624 */
625 int ssl3_write_bytes(SSL *s, int type, const void *buf_, int len)
626 {
627 const unsigned char *buf=buf_;
628 unsigned int tot,n,nw;
629 int i;
630
631 s->rwstate=SSL_NOTHING;
632 tot=s->s3->wnum;
633 s->s3->wnum=0;
634
635 if (SSL_in_init(s) && !s->in_handshake)
636 {
637 i=s->handshake_func(s);
638 if (i < 0) return(i);
639 if (i == 0)
640 {
641 SSLerr(SSL_F_SSL3_WRITE_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
642 return -1;
643 }
644 }
645
646 n=(len-tot);
647 for (;;)
648 {
649 if (n > s->max_send_fragment)
650 nw=s->max_send_fragment;
651 else
652 nw=n;
653
654 i=do_ssl3_write(s, type, &(buf[tot]), nw, 0);
655 if (i <= 0)
656 {
657 s->s3->wnum=tot;
658 return i;
659 }
660
661 if ((i == (int)n) ||
662 (type == SSL3_RT_APPLICATION_DATA &&
663 (s->mode & SSL_MODE_ENABLE_PARTIAL_WRITE)))
664 {
665 /* next chunk of data should get another prepended empty fragment
666 * in ciphersuites with known-IV weakness: */
667 s->s3->empty_fragment_done = 0;
668
669 return tot+i;
670 }
671
672 n-=i;
673 tot+=i;
674 }
675 }
676
677 static int do_ssl3_write(SSL *s, int type, const unsigned char *buf,
678 unsigned int len, int create_empty_fragment)
679 {
680 unsigned char *p,*plen;
681 int i,mac_size,clear=0;
682 int prefix_len=0;
683 int eivlen;
684 long align=0;
685 SSL3_RECORD *wr;
686 SSL3_BUFFER *wb=&(s->s3->wbuf);
687 SSL_SESSION *sess;
688
689 if (wb->buf == NULL)
690 if (!ssl3_setup_write_buffer(s))
691 return -1;
692
693 /* first check if there is a SSL3_BUFFER still being written
694 * out. This will happen with non blocking IO */
695 if (wb->left != 0)
696 return(ssl3_write_pending(s,type,buf,len));
697
698 /* If we have an alert to send, lets send it */
699 if (s->s3->alert_dispatch)
700 {
701 i=s->method->ssl_dispatch_alert(s);
702 if (i <= 0)
703 return(i);
704 /* if it went, fall through and send more stuff */
705 }
706
707 if (len == 0 && !create_empty_fragment)
708 return 0;
709
710 wr= &(s->s3->wrec);
711 sess=s->session;
712
713 if ( (sess == NULL) ||
714 (s->enc_write_ctx == NULL) ||
715 (EVP_MD_CTX_md(s->write_hash) == NULL))
716 {
717 #if 1
718 clear=s->enc_write_ctx?0:1; /* must be AEAD cipher */
719 #else
720 clear=1;
721 #endif
722 mac_size=0;
723 }
724 else
725 {
726 mac_size=EVP_MD_CTX_size(s->write_hash);
727 if (mac_size < 0)
728 goto err;
729 }
730
731 #if !defined(OPENSSL_NO_MULTIBLOCK) && EVP_CIPH_FLAG_TLS1_1_MULTIBLOCK
732 if (type==SSL3_RT_APPLICATION_DATA && s->compress==NULL &&
733 !SSL_USE_ETM(s) && SSL_USE_EXPLICIT_IV(s) && /*!SSL_IS_DTLS(s) &&*/
734 EVP_CIPHER_flags(s->enc_write_ctx->cipher)&EVP_CIPH_FLAG_TLS1_1_MULTIBLOCK)
735 do {
736 unsigned char aad[13];
737 EVP_CTRL_TLS1_1_MULTIBLOCK_PARAM mb_param = {NULL,aad,sizeof(aad),0};
738 int packlen;
739
740 memcpy(aad,s->s3->write_sequence,8);
741 aad[8]=type;
742 aad[9]=(unsigned char)(s->version>>8);
743 aad[10]=(unsigned char)(s->version);
744 aad[11]=(unsigned char)(len>>8);
745 aad[12]=(unsigned char)len;
746 packlen = EVP_CIPHER_CTX_ctrl(s->enc_write_ctx,
747 EVP_CTRL_TLS1_1_MULTIBLOCK_AAD,
748 sizeof(mb_param),&mb_param);
749
750 if (packlen==0 || packlen > wb->len) break;
751
752 mb_param.out = wb->buf;
753 mb_param.inp = buf;
754 mb_param.len = len;
755 EVP_CIPHER_CTX_ctrl(s->enc_write_ctx,
756 EVP_CTRL_TLS1_1_MULTIBLOCK_ENCRYPT,
757 sizeof(mb_param),&mb_param);
758
759 s->s3->write_sequence[7] += mb_param.interleave;
760 if (s->s3->write_sequence[7] < mb_param.interleave)
761 {
762 int j=6;
763 while (j>=0 && (++s->s3->write_sequence[j--])==0) ;
764 }
765
766 wb->offset=0;
767 wb->left = packlen;
768
769 /* memorize arguments so that ssl3_write_pending can detect bad write retries later */
770 s->s3->wpend_tot=len;
771 s->s3->wpend_buf=buf;
772 s->s3->wpend_type=type;
773 s->s3->wpend_ret=len;
774
775 /* we now just need to write the buffer */
776 return ssl3_write_pending(s,type,buf,len);
777 } while (0);
778 #endif
779
780 /* 'create_empty_fragment' is true only when this function calls itself */
781 if (!clear && !create_empty_fragment && !s->s3->empty_fragment_done)
782 {
783 /* countermeasure against known-IV weakness in CBC ciphersuites
784 * (see http://www.openssl.org/~bodo/tls-cbc.txt) */
785
786 if (s->s3->need_empty_fragments && type == SSL3_RT_APPLICATION_DATA)
787 {
788 /* recursive function call with 'create_empty_fragment' set;
789 * this prepares and buffers the data for an empty fragment
790 * (these 'prefix_len' bytes are sent out later
791 * together with the actual payload) */
792 prefix_len = do_ssl3_write(s, type, buf, 0, 1);
793 if (prefix_len <= 0)
794 goto err;
795
796 if (prefix_len >
797 (SSL3_RT_HEADER_LENGTH + SSL3_RT_SEND_MAX_ENCRYPTED_OVERHEAD))
798 {
799 /* insufficient space */
800 SSLerr(SSL_F_DO_SSL3_WRITE, ERR_R_INTERNAL_ERROR);
801 goto err;
802 }
803 }
804
805 s->s3->empty_fragment_done = 1;
806 }
807
808 if (create_empty_fragment)
809 {
810 #if defined(SSL3_ALIGN_PAYLOAD) && SSL3_ALIGN_PAYLOAD!=0
811 /* extra fragment would be couple of cipher blocks,
812 * which would be multiple of SSL3_ALIGN_PAYLOAD, so
813 * if we want to align the real payload, then we can
814 * just pretent we simply have two headers. */
815 align = (long)wb->buf + 2*SSL3_RT_HEADER_LENGTH;
816 align = (-align)&(SSL3_ALIGN_PAYLOAD-1);
817 #endif
818 p = wb->buf + align;
819 wb->offset = align;
820 }
821 else if (prefix_len)
822 {
823 p = wb->buf + wb->offset + prefix_len;
824 }
825 else
826 {
827 #if defined(SSL3_ALIGN_PAYLOAD) && SSL3_ALIGN_PAYLOAD!=0
828 align = (long)wb->buf + SSL3_RT_HEADER_LENGTH;
829 align = (-align)&(SSL3_ALIGN_PAYLOAD-1);
830 #endif
831 p = wb->buf + align;
832 wb->offset = align;
833 }
834
835 /* write the header */
836
837 *(p++)=type&0xff;
838 wr->type=type;
839
840 *(p++)=(s->version>>8);
841 /* Some servers hang if iniatial client hello is larger than 256
842 * bytes and record version number > TLS 1.0
843 */
844 if (s->state == SSL3_ST_CW_CLNT_HELLO_B
845 && !s->renegotiate
846 && TLS1_get_version(s) > TLS1_VERSION)
847 *(p++) = 0x1;
848 else
849 *(p++)=s->version&0xff;
850
851 /* field where we are to write out packet length */
852 plen=p;
853 p+=2;
854 /* Explicit IV length, block ciphers appropriate version flag */
855 if (s->enc_write_ctx && SSL_USE_EXPLICIT_IV(s))
856 {
857 int mode = EVP_CIPHER_CTX_mode(s->enc_write_ctx);
858 if (mode == EVP_CIPH_CBC_MODE)
859 {
860 eivlen = EVP_CIPHER_CTX_iv_length(s->enc_write_ctx);
861 if (eivlen <= 1)
862 eivlen = 0;
863 }
864 /* Need explicit part of IV for GCM mode */
865 else if (mode == EVP_CIPH_GCM_MODE)
866 eivlen = EVP_GCM_TLS_EXPLICIT_IV_LEN;
867 else
868 eivlen = 0;
869 }
870 else
871 eivlen = 0;
872
873 /* lets setup the record stuff. */
874 wr->data=p + eivlen;
875 wr->length=(int)len;
876 wr->input=(unsigned char *)buf;
877
878 /* we now 'read' from wr->input, wr->length bytes into
879 * wr->data */
880
881 /* first we compress */
882 if (s->compress != NULL)
883 {
884 if (!ssl3_do_compress(s))
885 {
886 SSLerr(SSL_F_DO_SSL3_WRITE,SSL_R_COMPRESSION_FAILURE);
887 goto err;
888 }
889 }
890 else
891 {
892 memcpy(wr->data,wr->input,wr->length);
893 wr->input=wr->data;
894 }
895
896 /* we should still have the output to wr->data and the input
897 * from wr->input. Length should be wr->length.
898 * wr->data still points in the wb->buf */
899
900 if (!SSL_USE_ETM(s) && mac_size != 0)
901 {
902 if (s->method->ssl3_enc->mac(s,&(p[wr->length + eivlen]),1) < 0)
903 goto err;
904 wr->length+=mac_size;
905 }
906
907 wr->input=p;
908 wr->data=p;
909
910 if (eivlen)
911 {
912 /* if (RAND_pseudo_bytes(p, eivlen) <= 0)
913 goto err; */
914 wr->length += eivlen;
915 }
916
917 /* ssl3_enc can only have an error on read */
918 s->method->ssl3_enc->enc(s,1);
919
920 if (SSL_USE_ETM(s) && mac_size != 0)
921 {
922 if (s->method->ssl3_enc->mac(s,p + wr->length,1) < 0)
923 goto err;
924 wr->length+=mac_size;
925 }
926
927 /* record length after mac and block padding */
928 s2n(wr->length,plen);
929
930 if (s->msg_callback)
931 s->msg_callback(1, 0, SSL3_RT_HEADER, plen - 5, 5, s, s->msg_callback_arg);
932
933 /* we should now have
934 * wr->data pointing to the encrypted data, which is
935 * wr->length long */
936 wr->type=type; /* not needed but helps for debugging */
937 wr->length+=SSL3_RT_HEADER_LENGTH;
938
939 if (create_empty_fragment)
940 {
941 /* we are in a recursive call;
942 * just return the length, don't write out anything here
943 */
944 return wr->length;
945 }
946
947 /* now let's set up wb */
948 wb->left = prefix_len + wr->length;
949
950 /* memorize arguments so that ssl3_write_pending can detect bad write retries later */
951 s->s3->wpend_tot=len;
952 s->s3->wpend_buf=buf;
953 s->s3->wpend_type=type;
954 s->s3->wpend_ret=len;
955
956 /* we now just need to write the buffer */
957 return ssl3_write_pending(s,type,buf,len);
958 err:
959 return -1;
960 }
961
962 /* if s->s3->wbuf.left != 0, we need to call this */
963 int ssl3_write_pending(SSL *s, int type, const unsigned char *buf,
964 unsigned int len)
965 {
966 int i;
967 SSL3_BUFFER *wb=&(s->s3->wbuf);
968
969 /* XXXX */
970 if ((s->s3->wpend_tot > (int)len)
971 || ((s->s3->wpend_buf != buf) &&
972 !(s->mode & SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER))
973 || (s->s3->wpend_type != type))
974 {
975 SSLerr(SSL_F_SSL3_WRITE_PENDING,SSL_R_BAD_WRITE_RETRY);
976 return(-1);
977 }
978
979 for (;;)
980 {
981 clear_sys_error();
982 if (s->wbio != NULL)
983 {
984 s->rwstate=SSL_WRITING;
985 i=BIO_write(s->wbio,
986 (char *)&(wb->buf[wb->offset]),
987 (unsigned int)wb->left);
988 }
989 else
990 {
991 SSLerr(SSL_F_SSL3_WRITE_PENDING,SSL_R_BIO_NOT_SET);
992 i= -1;
993 }
994 if (i == wb->left)
995 {
996 wb->left=0;
997 wb->offset+=i;
998 if (s->mode & SSL_MODE_RELEASE_BUFFERS &&
999 !SSL_IS_DTLS(s))
1000 ssl3_release_write_buffer(s);
1001 s->rwstate=SSL_NOTHING;
1002 return(s->s3->wpend_ret);
1003 }
1004 else if (i <= 0) {
1005 if (s->version == DTLS1_VERSION ||
1006 s->version == DTLS1_BAD_VER) {
1007 /* For DTLS, just drop it. That's kind of the whole
1008 point in using a datagram service */
1009 wb->left = 0;
1010 }
1011 return(i);
1012 }
1013 wb->offset+=i;
1014 wb->left-=i;
1015 }
1016 }
1017
1018 /* Return up to 'len' payload bytes received in 'type' records.
1019 * 'type' is one of the following:
1020 *
1021 * - SSL3_RT_HANDSHAKE (when ssl3_get_message calls us)
1022 * - SSL3_RT_APPLICATION_DATA (when ssl3_read calls us)
1023 * - 0 (during a shutdown, no data has to be returned)
1024 *
1025 * If we don't have stored data to work from, read a SSL/TLS record first
1026 * (possibly multiple records if we still don't have anything to return).
1027 *
1028 * This function must handle any surprises the peer may have for us, such as
1029 * Alert records (e.g. close_notify), ChangeCipherSpec records (not really
1030 * a surprise, but handled as if it were), or renegotiation requests.
1031 * Also if record payloads contain fragments too small to process, we store
1032 * them until there is enough for the respective protocol (the record protocol
1033 * may use arbitrary fragmentation and even interleaving):
1034 * Change cipher spec protocol
1035 * just 1 byte needed, no need for keeping anything stored
1036 * Alert protocol
1037 * 2 bytes needed (AlertLevel, AlertDescription)
1038 * Handshake protocol
1039 * 4 bytes needed (HandshakeType, uint24 length) -- we just have
1040 * to detect unexpected Client Hello and Hello Request messages
1041 * here, anything else is handled by higher layers
1042 * Application data protocol
1043 * none of our business
1044 */
1045 int ssl3_read_bytes(SSL *s, int type, unsigned char *buf, int len, int peek)
1046 {
1047 int al,i,j,ret;
1048 unsigned int n;
1049 SSL3_RECORD *rr;
1050 void (*cb)(const SSL *ssl,int type2,int val)=NULL;
1051
1052 if (s->s3->rbuf.buf == NULL) /* Not initialized yet */
1053 if (!ssl3_setup_read_buffer(s))
1054 return(-1);
1055
1056 if ((type && (type != SSL3_RT_APPLICATION_DATA) && (type != SSL3_RT_HANDSHAKE) && type) ||
1057 (peek && (type != SSL3_RT_APPLICATION_DATA)))
1058 {
1059 SSLerr(SSL_F_SSL3_READ_BYTES, ERR_R_INTERNAL_ERROR);
1060 return -1;
1061 }
1062
1063 if ((type == SSL3_RT_HANDSHAKE) && (s->s3->handshake_fragment_len > 0))
1064 /* (partially) satisfy request from storage */
1065 {
1066 unsigned char *src = s->s3->handshake_fragment;
1067 unsigned char *dst = buf;
1068 unsigned int k;
1069
1070 /* peek == 0 */
1071 n = 0;
1072 while ((len > 0) && (s->s3->handshake_fragment_len > 0))
1073 {
1074 *dst++ = *src++;
1075 len--; s->s3->handshake_fragment_len--;
1076 n++;
1077 }
1078 /* move any remaining fragment bytes: */
1079 for (k = 0; k < s->s3->handshake_fragment_len; k++)
1080 s->s3->handshake_fragment[k] = *src++;
1081 return n;
1082 }
1083
1084 /* Now s->s3->handshake_fragment_len == 0 if type == SSL3_RT_HANDSHAKE. */
1085
1086 if (!s->in_handshake && SSL_in_init(s))
1087 {
1088 /* type == SSL3_RT_APPLICATION_DATA */
1089 i=s->handshake_func(s);
1090 if (i < 0) return(i);
1091 if (i == 0)
1092 {
1093 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
1094 return(-1);
1095 }
1096 }
1097 start:
1098 s->rwstate=SSL_NOTHING;
1099
1100 /* s->s3->rrec.type - is the type of record
1101 * s->s3->rrec.data, - data
1102 * s->s3->rrec.off, - offset into 'data' for next read
1103 * s->s3->rrec.length, - number of bytes. */
1104 rr = &(s->s3->rrec);
1105
1106 /* get new packet if necessary */
1107 if ((rr->length == 0) || (s->rstate == SSL_ST_READ_BODY))
1108 {
1109 ret=ssl3_get_record(s);
1110 if (ret <= 0) return(ret);
1111 }
1112
1113 /* we now have a packet which can be read and processed */
1114
1115 if (s->s3->change_cipher_spec /* set when we receive ChangeCipherSpec,
1116 * reset by ssl3_get_finished */
1117 && (rr->type != SSL3_RT_HANDSHAKE))
1118 {
1119 al=SSL_AD_UNEXPECTED_MESSAGE;
1120 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_DATA_BETWEEN_CCS_AND_FINISHED);
1121 goto f_err;
1122 }
1123
1124 /* If the other end has shut down, throw anything we read away
1125 * (even in 'peek' mode) */
1126 if (s->shutdown & SSL_RECEIVED_SHUTDOWN)
1127 {
1128 rr->length=0;
1129 s->rwstate=SSL_NOTHING;
1130 return(0);
1131 }
1132
1133
1134 if (type == rr->type) /* SSL3_RT_APPLICATION_DATA or SSL3_RT_HANDSHAKE */
1135 {
1136 /* make sure that we are not getting application data when we
1137 * are doing a handshake for the first time */
1138 if (SSL_in_init(s) && (type == SSL3_RT_APPLICATION_DATA) &&
1139 (s->enc_read_ctx == NULL))
1140 {
1141 al=SSL_AD_UNEXPECTED_MESSAGE;
1142 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_APP_DATA_IN_HANDSHAKE);
1143 goto f_err;
1144 }
1145
1146 if (len <= 0) return(len);
1147
1148 if ((unsigned int)len > rr->length)
1149 n = rr->length;
1150 else
1151 n = (unsigned int)len;
1152
1153 memcpy(buf,&(rr->data[rr->off]),n);
1154 if (!peek)
1155 {
1156 rr->length-=n;
1157 rr->off+=n;
1158 if (rr->length == 0)
1159 {
1160 s->rstate=SSL_ST_READ_HEADER;
1161 rr->off=0;
1162 if (s->mode & SSL_MODE_RELEASE_BUFFERS)
1163 ssl3_release_read_buffer(s);
1164 }
1165 }
1166 return(n);
1167 }
1168
1169
1170 /* If we get here, then type != rr->type; if we have a handshake
1171 * message, then it was unexpected (Hello Request or Client Hello). */
1172
1173 /* In case of record types for which we have 'fragment' storage,
1174 * fill that so that we can process the data at a fixed place.
1175 */
1176 {
1177 unsigned int dest_maxlen = 0;
1178 unsigned char *dest = NULL;
1179 unsigned int *dest_len = NULL;
1180
1181 if (rr->type == SSL3_RT_HANDSHAKE)
1182 {
1183 dest_maxlen = sizeof s->s3->handshake_fragment;
1184 dest = s->s3->handshake_fragment;
1185 dest_len = &s->s3->handshake_fragment_len;
1186 }
1187 else if (rr->type == SSL3_RT_ALERT)
1188 {
1189 dest_maxlen = sizeof s->s3->alert_fragment;
1190 dest = s->s3->alert_fragment;
1191 dest_len = &s->s3->alert_fragment_len;
1192 }
1193 #ifndef OPENSSL_NO_HEARTBEATS
1194 else if (rr->type == TLS1_RT_HEARTBEAT)
1195 {
1196 tls1_process_heartbeat(s);
1197
1198 /* Exit and notify application to read again */
1199 rr->length = 0;
1200 s->rwstate=SSL_READING;
1201 BIO_clear_retry_flags(SSL_get_rbio(s));
1202 BIO_set_retry_read(SSL_get_rbio(s));
1203 return(-1);
1204 }
1205 #endif
1206
1207 if (dest_maxlen > 0)
1208 {
1209 n = dest_maxlen - *dest_len; /* available space in 'dest' */
1210 if (rr->length < n)
1211 n = rr->length; /* available bytes */
1212
1213 /* now move 'n' bytes: */
1214 while (n-- > 0)
1215 {
1216 dest[(*dest_len)++] = rr->data[rr->off++];
1217 rr->length--;
1218 }
1219
1220 if (*dest_len < dest_maxlen)
1221 goto start; /* fragment was too small */
1222 }
1223 }
1224
1225 /* s->s3->handshake_fragment_len == 4 iff rr->type == SSL3_RT_HANDSHAKE;
1226 * s->s3->alert_fragment_len == 2 iff rr->type == SSL3_RT_ALERT.
1227 * (Possibly rr is 'empty' now, i.e. rr->length may be 0.) */
1228
1229 /* If we are a client, check for an incoming 'Hello Request': */
1230 if ((!s->server) &&
1231 (s->s3->handshake_fragment_len >= 4) &&
1232 (s->s3->handshake_fragment[0] == SSL3_MT_HELLO_REQUEST) &&
1233 (s->session != NULL) && (s->session->cipher != NULL))
1234 {
1235 s->s3->handshake_fragment_len = 0;
1236
1237 if ((s->s3->handshake_fragment[1] != 0) ||
1238 (s->s3->handshake_fragment[2] != 0) ||
1239 (s->s3->handshake_fragment[3] != 0))
1240 {
1241 al=SSL_AD_DECODE_ERROR;
1242 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_BAD_HELLO_REQUEST);
1243 goto f_err;
1244 }
1245
1246 if (s->msg_callback)
1247 s->msg_callback(0, s->version, SSL3_RT_HANDSHAKE, s->s3->handshake_fragment, 4, s, s->msg_callback_arg);
1248
1249 if (SSL_is_init_finished(s) &&
1250 !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS) &&
1251 !s->s3->renegotiate)
1252 {
1253 ssl3_renegotiate(s);
1254 if (ssl3_renegotiate_check(s))
1255 {
1256 i=s->handshake_func(s);
1257 if (i < 0) return(i);
1258 if (i == 0)
1259 {
1260 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
1261 return(-1);
1262 }
1263
1264 if (!(s->mode & SSL_MODE_AUTO_RETRY))
1265 {
1266 if (s->s3->rbuf.left == 0) /* no read-ahead left? */
1267 {
1268 BIO *bio;
1269 /* In the case where we try to read application data,
1270 * but we trigger an SSL handshake, we return -1 with
1271 * the retry option set. Otherwise renegotiation may
1272 * cause nasty problems in the blocking world */
1273 s->rwstate=SSL_READING;
1274 bio=SSL_get_rbio(s);
1275 BIO_clear_retry_flags(bio);
1276 BIO_set_retry_read(bio);
1277 return(-1);
1278 }
1279 }
1280 }
1281 }
1282 /* we either finished a handshake or ignored the request,
1283 * now try again to obtain the (application) data we were asked for */
1284 goto start;
1285 }
1286 /* If we are a server and get a client hello when renegotiation isn't
1287 * allowed send back a no renegotiation alert and carry on.
1288 * WARNING: experimental code, needs reviewing (steve)
1289 */
1290 if (s->server &&
1291 SSL_is_init_finished(s) &&
1292 !s->s3->send_connection_binding &&
1293 (s->version > SSL3_VERSION) &&
1294 (s->s3->handshake_fragment_len >= 4) &&
1295 (s->s3->handshake_fragment[0] == SSL3_MT_CLIENT_HELLO) &&
1296 (s->session != NULL) && (s->session->cipher != NULL) &&
1297 !(s->ctx->options & SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION))
1298
1299 {
1300 /*s->s3->handshake_fragment_len = 0;*/
1301 rr->length = 0;
1302 ssl3_send_alert(s,SSL3_AL_WARNING, SSL_AD_NO_RENEGOTIATION);
1303 goto start;
1304 }
1305 if (s->s3->alert_fragment_len >= 2)
1306 {
1307 int alert_level = s->s3->alert_fragment[0];
1308 int alert_descr = s->s3->alert_fragment[1];
1309
1310 s->s3->alert_fragment_len = 0;
1311
1312 if (s->msg_callback)
1313 s->msg_callback(0, s->version, SSL3_RT_ALERT, s->s3->alert_fragment, 2, s, s->msg_callback_arg);
1314
1315 if (s->info_callback != NULL)
1316 cb=s->info_callback;
1317 else if (s->ctx->info_callback != NULL)
1318 cb=s->ctx->info_callback;
1319
1320 if (cb != NULL)
1321 {
1322 j = (alert_level << 8) | alert_descr;
1323 cb(s, SSL_CB_READ_ALERT, j);
1324 }
1325
1326 if (alert_level == 1) /* warning */
1327 {
1328 s->s3->warn_alert = alert_descr;
1329 if (alert_descr == SSL_AD_CLOSE_NOTIFY)
1330 {
1331 s->shutdown |= SSL_RECEIVED_SHUTDOWN;
1332 return(0);
1333 }
1334 /* This is a warning but we receive it if we requested
1335 * renegotiation and the peer denied it. Terminate with
1336 * a fatal alert because if application tried to
1337 * renegotiatie it presumably had a good reason and
1338 * expects it to succeed.
1339 *
1340 * In future we might have a renegotiation where we
1341 * don't care if the peer refused it where we carry on.
1342 */
1343 else if (alert_descr == SSL_AD_NO_RENEGOTIATION)
1344 {
1345 al = SSL_AD_HANDSHAKE_FAILURE;
1346 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_NO_RENEGOTIATION);
1347 goto f_err;
1348 }
1349 #ifdef SSL_AD_MISSING_SRP_USERNAME
1350 else if (alert_descr == SSL_AD_MISSING_SRP_USERNAME)
1351 return(0);
1352 #endif
1353 }
1354 else if (alert_level == 2) /* fatal */
1355 {
1356 char tmp[16];
1357
1358 s->rwstate=SSL_NOTHING;
1359 s->s3->fatal_alert = alert_descr;
1360 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_AD_REASON_OFFSET + alert_descr);
1361 BIO_snprintf(tmp,sizeof tmp,"%d",alert_descr);
1362 ERR_add_error_data(2,"SSL alert number ",tmp);
1363 s->shutdown|=SSL_RECEIVED_SHUTDOWN;
1364 SSL_CTX_remove_session(s->ctx,s->session);
1365 return(0);
1366 }
1367 else
1368 {
1369 al=SSL_AD_ILLEGAL_PARAMETER;
1370 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNKNOWN_ALERT_TYPE);
1371 goto f_err;
1372 }
1373
1374 goto start;
1375 }
1376
1377 if (s->shutdown & SSL_SENT_SHUTDOWN) /* but we have not received a shutdown */
1378 {
1379 s->rwstate=SSL_NOTHING;
1380 rr->length=0;
1381 return(0);
1382 }
1383
1384 if (rr->type == SSL3_RT_CHANGE_CIPHER_SPEC)
1385 {
1386 /* 'Change Cipher Spec' is just a single byte, so we know
1387 * exactly what the record payload has to look like */
1388 if ( (rr->length != 1) || (rr->off != 0) ||
1389 (rr->data[0] != SSL3_MT_CCS))
1390 {
1391 al=SSL_AD_ILLEGAL_PARAMETER;
1392 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_BAD_CHANGE_CIPHER_SPEC);
1393 goto f_err;
1394 }
1395
1396 /* Check we have a cipher to change to */
1397 if (s->s3->tmp.new_cipher == NULL)
1398 {
1399 al=SSL_AD_UNEXPECTED_MESSAGE;
1400 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_CCS_RECEIVED_EARLY);
1401 goto f_err;
1402 }
1403
1404 rr->length=0;
1405
1406 if (s->msg_callback)
1407 s->msg_callback(0, s->version, SSL3_RT_CHANGE_CIPHER_SPEC, rr->data, 1, s, s->msg_callback_arg);
1408
1409 s->s3->change_cipher_spec=1;
1410 if (!ssl3_do_change_cipher_spec(s))
1411 goto err;
1412 else
1413 goto start;
1414 }
1415
1416 /* Unexpected handshake message (Client Hello, or protocol violation) */
1417 if ((s->s3->handshake_fragment_len >= 4) && !s->in_handshake)
1418 {
1419 if (((s->state&SSL_ST_MASK) == SSL_ST_OK) &&
1420 !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS))
1421 {
1422 #if 0 /* worked only because C operator preferences are not as expected (and
1423 * because this is not really needed for clients except for detecting
1424 * protocol violations): */
1425 s->state=SSL_ST_BEFORE|(s->server)
1426 ?SSL_ST_ACCEPT
1427 :SSL_ST_CONNECT;
1428 #else
1429 s->state = s->server ? SSL_ST_ACCEPT : SSL_ST_CONNECT;
1430 #endif
1431 s->renegotiate=1;
1432 s->new_session=1;
1433 }
1434 i=s->handshake_func(s);
1435 if (i < 0) return(i);
1436 if (i == 0)
1437 {
1438 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
1439 return(-1);
1440 }
1441
1442 if (!(s->mode & SSL_MODE_AUTO_RETRY))
1443 {
1444 if (s->s3->rbuf.left == 0) /* no read-ahead left? */
1445 {
1446 BIO *bio;
1447 /* In the case where we try to read application data,
1448 * but we trigger an SSL handshake, we return -1 with
1449 * the retry option set. Otherwise renegotiation may
1450 * cause nasty problems in the blocking world */
1451 s->rwstate=SSL_READING;
1452 bio=SSL_get_rbio(s);
1453 BIO_clear_retry_flags(bio);
1454 BIO_set_retry_read(bio);
1455 return(-1);
1456 }
1457 }
1458 goto start;
1459 }
1460
1461 switch (rr->type)
1462 {
1463 default:
1464 #ifndef OPENSSL_NO_TLS
1465 /* TLS up to v1.1 just ignores unknown message types:
1466 * TLS v1.2 give an unexpected message alert.
1467 */
1468 if (s->version >= TLS1_VERSION && s->version <= TLS1_1_VERSION)
1469 {
1470 rr->length = 0;
1471 goto start;
1472 }
1473 #endif
1474 al=SSL_AD_UNEXPECTED_MESSAGE;
1475 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNEXPECTED_RECORD);
1476 goto f_err;
1477 case SSL3_RT_CHANGE_CIPHER_SPEC:
1478 case SSL3_RT_ALERT:
1479 case SSL3_RT_HANDSHAKE:
1480 /* we already handled all of these, with the possible exception
1481 * of SSL3_RT_HANDSHAKE when s->in_handshake is set, but that
1482 * should not happen when type != rr->type */
1483 al=SSL_AD_UNEXPECTED_MESSAGE;
1484 SSLerr(SSL_F_SSL3_READ_BYTES,ERR_R_INTERNAL_ERROR);
1485 goto f_err;
1486 case SSL3_RT_APPLICATION_DATA:
1487 /* At this point, we were expecting handshake data,
1488 * but have application data. If the library was
1489 * running inside ssl3_read() (i.e. in_read_app_data
1490 * is set) and it makes sense to read application data
1491 * at this point (session renegotiation not yet started),
1492 * we will indulge it.
1493 */
1494 if (s->s3->in_read_app_data &&
1495 (s->s3->total_renegotiations != 0) &&
1496 ((
1497 (s->state & SSL_ST_CONNECT) &&
1498 (s->state >= SSL3_ST_CW_CLNT_HELLO_A) &&
1499 (s->state <= SSL3_ST_CR_SRVR_HELLO_A)
1500 ) || (
1501 (s->state & SSL_ST_ACCEPT) &&
1502 (s->state <= SSL3_ST_SW_HELLO_REQ_A) &&
1503 (s->state >= SSL3_ST_SR_CLNT_HELLO_A)
1504 )
1505 ))
1506 {
1507 s->s3->in_read_app_data=2;
1508 return(-1);
1509 }
1510 else
1511 {
1512 al=SSL_AD_UNEXPECTED_MESSAGE;
1513 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNEXPECTED_RECORD);
1514 goto f_err;
1515 }
1516 }
1517 /* not reached */
1518
1519 f_err:
1520 ssl3_send_alert(s,SSL3_AL_FATAL,al);
1521 err:
1522 return(-1);
1523 }
1524
1525 int ssl3_do_change_cipher_spec(SSL *s)
1526 {
1527 int i;
1528 const char *sender;
1529 int slen;
1530
1531 if (s->state & SSL_ST_ACCEPT)
1532 i=SSL3_CHANGE_CIPHER_SERVER_READ;
1533 else
1534 i=SSL3_CHANGE_CIPHER_CLIENT_READ;
1535
1536 if (s->s3->tmp.key_block == NULL)
1537 {
1538 if (s->session == NULL)
1539 {
1540 /* might happen if dtls1_read_bytes() calls this */
1541 SSLerr(SSL_F_SSL3_DO_CHANGE_CIPHER_SPEC,SSL_R_CCS_RECEIVED_EARLY);
1542 return (0);
1543 }
1544
1545 s->session->cipher=s->s3->tmp.new_cipher;
1546 if (!s->method->ssl3_enc->setup_key_block(s)) return(0);
1547 }
1548
1549 if (!s->method->ssl3_enc->change_cipher_state(s,i))
1550 return(0);
1551
1552 /* we have to record the message digest at
1553 * this point so we can get it before we read
1554 * the finished message */
1555 if (s->state & SSL_ST_CONNECT)
1556 {
1557 sender=s->method->ssl3_enc->server_finished_label;
1558 slen=s->method->ssl3_enc->server_finished_label_len;
1559 }
1560 else
1561 {
1562 sender=s->method->ssl3_enc->client_finished_label;
1563 slen=s->method->ssl3_enc->client_finished_label_len;
1564 }
1565
1566 i = s->method->ssl3_enc->final_finish_mac(s,
1567 sender,slen,s->s3->tmp.peer_finish_md);
1568 if (i == 0)
1569 {
1570 SSLerr(SSL_F_SSL3_DO_CHANGE_CIPHER_SPEC, ERR_R_INTERNAL_ERROR);
1571 return 0;
1572 }
1573 s->s3->tmp.peer_finish_md_len = i;
1574
1575 return(1);
1576 }
1577
1578 int ssl3_send_alert(SSL *s, int level, int desc)
1579 {
1580 /* Map tls/ssl alert value to correct one */
1581 desc=s->method->ssl3_enc->alert_value(desc);
1582 if (s->version == SSL3_VERSION && desc == SSL_AD_PROTOCOL_VERSION)
1583 desc = SSL_AD_HANDSHAKE_FAILURE; /* SSL 3.0 does not have protocol_version alerts */
1584 if (desc < 0) return -1;
1585 /* If a fatal one, remove from cache */
1586 if ((level == 2) && (s->session != NULL))
1587 SSL_CTX_remove_session(s->ctx,s->session);
1588
1589 s->s3->alert_dispatch=1;
1590 s->s3->send_alert[0]=level;
1591 s->s3->send_alert[1]=desc;
1592 if (s->s3->wbuf.left == 0) /* data still being written out? */
1593 return s->method->ssl_dispatch_alert(s);
1594 /* else data is still being written out, we will get written
1595 * some time in the future */
1596 return -1;
1597 }
1598
1599 int ssl3_dispatch_alert(SSL *s)
1600 {
1601 int i,j;
1602 void (*cb)(const SSL *ssl,int type,int val)=NULL;
1603
1604 s->s3->alert_dispatch=0;
1605 i = do_ssl3_write(s, SSL3_RT_ALERT, &s->s3->send_alert[0], 2, 0);
1606 if (i <= 0)
1607 {
1608 s->s3->alert_dispatch=1;
1609 }
1610 else
1611 {
1612 /* Alert sent to BIO. If it is important, flush it now.
1613 * If the message does not get sent due to non-blocking IO,
1614 * we will not worry too much. */
1615 if (s->s3->send_alert[0] == SSL3_AL_FATAL)
1616 (void)BIO_flush(s->wbio);
1617
1618 if (s->msg_callback)
1619 s->msg_callback(1, s->version, SSL3_RT_ALERT, s->s3->send_alert, 2, s, s->msg_callback_arg);
1620
1621 if (s->info_callback != NULL)
1622 cb=s->info_callback;
1623 else if (s->ctx->info_callback != NULL)
1624 cb=s->ctx->info_callback;
1625
1626 if (cb != NULL)
1627 {
1628 j=(s->s3->send_alert[0]<<8)|s->s3->send_alert[1];
1629 cb(s,SSL_CB_WRITE_ALERT,j);
1630 }
1631 }
1632 return(i);
1633 }
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