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 static int do_ssl3_write(SSL *s, int type, const unsigned char *buf,
121 unsigned int len, int create_empty_fragment);
122 static int ssl3_get_record(SSL *s);
123
ssl3_read_n(SSL * s,int n,int max,int extend)124 int ssl3_read_n(SSL *s, int n, int max, int extend)
125 {
126 /* If extend == 0, obtain new n-byte packet; if extend == 1, increase
127 * packet by another n bytes.
128 * The packet will be in the sub-array of s->s3->rbuf.buf specified
129 * by s->packet and s->packet_length.
130 * (If s->read_ahead is set, 'max' bytes may be stored in rbuf
131 * [plus s->packet_length bytes if extend == 1].)
132 */
133 int i,len,left;
134 long align=0;
135 unsigned char *pkt;
136 SSL3_BUFFER *rb;
137
138 if (n <= 0) return n;
139
140 rb = &(s->s3->rbuf);
141 if (rb->buf == NULL)
142 if (!ssl3_setup_read_buffer(s))
143 return -1;
144
145 left = rb->left;
146 #if defined(SSL3_ALIGN_PAYLOAD) && SSL3_ALIGN_PAYLOAD!=0
147 align = (long)rb->buf + SSL3_RT_HEADER_LENGTH;
148 align = (-align)&(SSL3_ALIGN_PAYLOAD-1);
149 #endif
150
151 if (!extend)
152 {
153 /* start with empty packet ... */
154 if (left == 0)
155 rb->offset = align;
156 else if (align != 0 && left >= SSL3_RT_HEADER_LENGTH)
157 {
158 /* check if next packet length is large
159 * enough to justify payload alignment... */
160 pkt = rb->buf + rb->offset;
161 if (pkt[0] == SSL3_RT_APPLICATION_DATA
162 && (pkt[3]<<8|pkt[4]) >= 128)
163 {
164 /* Note that even if packet is corrupted
165 * and its length field is insane, we can
166 * only be led to wrong decision about
167 * whether memmove will occur or not.
168 * Header values has no effect on memmove
169 * arguments and therefore no buffer
170 * overrun can be triggered. */
171 memmove (rb->buf+align,pkt,left);
172 rb->offset = align;
173 }
174 }
175 s->packet = rb->buf + rb->offset;
176 s->packet_length = 0;
177 /* ... now we can act as if 'extend' was set */
178 }
179
180 /* For DTLS/UDP reads should not span multiple packets
181 * because the read operation returns the whole packet
182 * at once (as long as it fits into the buffer). */
183 if (SSL_version(s) == DTLS1_VERSION || SSL_version(s) == DTLS1_BAD_VER)
184 {
185 if (left > 0 && n > left)
186 n = left;
187 }
188
189 /* if there is enough in the buffer from a previous read, take some */
190 if (left >= n)
191 {
192 s->packet_length+=n;
193 rb->left=left-n;
194 rb->offset+=n;
195 return(n);
196 }
197
198 /* else we need to read more data */
199
200 len = s->packet_length;
201 pkt = rb->buf+align;
202 /* Move any available bytes to front of buffer:
203 * 'len' bytes already pointed to by 'packet',
204 * 'left' extra ones at the end */
205 if (s->packet != pkt) /* len > 0 */
206 {
207 memmove(pkt, s->packet, len+left);
208 s->packet = pkt;
209 rb->offset = len + align;
210 }
211
212 if (n > (int)(rb->len - rb->offset)) /* does not happen */
213 {
214 SSLerr(SSL_F_SSL3_READ_N,ERR_R_INTERNAL_ERROR);
215 return -1;
216 }
217
218 if (!s->read_ahead)
219 /* ignore max parameter */
220 max = n;
221 else
222 {
223 if (max < n)
224 max = n;
225 if (max > (int)(rb->len - rb->offset))
226 max = rb->len - rb->offset;
227 }
228
229 while (left < n)
230 {
231 /* Now we have len+left bytes at the front of s->s3->rbuf.buf
232 * and need to read in more until we have len+n (up to
233 * len+max if possible) */
234
235 clear_sys_error();
236 if (s->rbio != NULL)
237 {
238 s->rwstate=SSL_READING;
239 i=BIO_read(s->rbio,pkt+len+left, max-left);
240 }
241 else
242 {
243 SSLerr(SSL_F_SSL3_READ_N,SSL_R_READ_BIO_NOT_SET);
244 i = -1;
245 }
246
247 if (i <= 0)
248 {
249 rb->left = left;
250 if (s->mode & SSL_MODE_RELEASE_BUFFERS &&
251 SSL_version(s) != DTLS1_VERSION && SSL_version(s) != DTLS1_BAD_VER)
252 if (len+left == 0)
253 ssl3_release_read_buffer(s);
254 return(i);
255 }
256 left+=i;
257 /* reads should *never* span multiple packets for DTLS because
258 * the underlying transport protocol is message oriented as opposed
259 * to byte oriented as in the TLS case. */
260 if (SSL_version(s) == DTLS1_VERSION || SSL_version(s) == DTLS1_BAD_VER)
261 {
262 if (n > left)
263 n = left; /* makes the while condition false */
264 }
265 }
266
267 /* done reading, now the book-keeping */
268 rb->offset += n;
269 rb->left = left - n;
270 s->packet_length += n;
271 s->rwstate=SSL_NOTHING;
272 return(n);
273 }
274
275 /* Call this to get a new input record.
276 * It will return <= 0 if more data is needed, normally due to an error
277 * or non-blocking IO.
278 * When it finishes, one packet has been decoded and can be found in
279 * ssl->s3->rrec.type - is the type of record
280 * ssl->s3->rrec.data, - data
281 * ssl->s3->rrec.length, - number of bytes
282 */
283 /* used only by ssl3_read_bytes */
ssl3_get_record(SSL * s)284 static int ssl3_get_record(SSL *s)
285 {
286 int ssl_major,ssl_minor,al;
287 int enc_err,n,i,ret= -1;
288 SSL3_RECORD *rr;
289 SSL_SESSION *sess;
290 unsigned char *p;
291 unsigned char md[EVP_MAX_MD_SIZE];
292 short version;
293 int mac_size;
294 int clear=0;
295 size_t extra;
296 int decryption_failed_or_bad_record_mac = 0;
297 unsigned char *mac = NULL;
298 #if defined(SSL3_ALIGN_PAYLOAD) && SSL3_ALIGN_PAYLOAD!=0
299 long align=SSL3_ALIGN_PAYLOAD;
300 #else
301 long align=0;
302 #endif
303
304 rr= &(s->s3->rrec);
305 sess=s->session;
306
307 if (s->options & SSL_OP_MICROSOFT_BIG_SSLV3_BUFFER)
308 extra=SSL3_RT_MAX_EXTRA;
309 else
310 extra=0;
311 if (!(SSL_get_mode(s) & SSL_MODE_SMALL_BUFFERS) &&
312 extra && !s->s3->init_extra)
313 {
314 /* An application error: SLS_OP_MICROSOFT_BIG_SSLV3_BUFFER
315 * set after ssl3_setup_buffers() was done */
316 SSLerr(SSL_F_SSL3_GET_RECORD, ERR_R_INTERNAL_ERROR);
317 return -1;
318 }
319
320 again:
321 /* check if we have the header */
322 if ( (s->rstate != SSL_ST_READ_BODY) ||
323 (s->packet_length < SSL3_RT_HEADER_LENGTH))
324 {
325 n=ssl3_read_n(s, SSL3_RT_HEADER_LENGTH, s->s3->rbuf.len, 0);
326 if (n <= 0) return(n); /* error or non-blocking */
327 s->rstate=SSL_ST_READ_BODY;
328
329 p=s->packet;
330
331 /* Pull apart the header into the SSL3_RECORD */
332 rr->type= *(p++);
333 ssl_major= *(p++);
334 ssl_minor= *(p++);
335 version=(ssl_major<<8)|ssl_minor;
336 n2s(p,rr->length);
337 #if 0
338 fprintf(stderr, "Record type=%d, Length=%d\n", rr->type, rr->length);
339 #endif
340
341 /* Lets check version */
342 if (!s->first_packet)
343 {
344 if (version != s->version)
345 {
346 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_WRONG_VERSION_NUMBER);
347 if ((s->version & 0xFF00) == (version & 0xFF00))
348 /* Send back error using their minor version number :-) */
349 s->version = (unsigned short)version;
350 al=SSL_AD_PROTOCOL_VERSION;
351 goto f_err;
352 }
353 }
354
355 if ((version>>8) != SSL3_VERSION_MAJOR)
356 {
357 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_WRONG_VERSION_NUMBER);
358 goto err;
359 }
360
361 /* If we receive a valid record larger than the current buffer size,
362 * allocate some memory for it.
363 */
364 if (rr->length > s->s3->rbuf.len - SSL3_RT_HEADER_LENGTH - align)
365 {
366 if ((p=OPENSSL_realloc(s->s3->rbuf.buf, rr->length + SSL3_RT_HEADER_LENGTH + align))==NULL)
367 {
368 SSLerr(SSL_F_SSL3_GET_RECORD,ERR_R_MALLOC_FAILURE);
369 goto err;
370 }
371 s->s3->rbuf.buf=p;
372 s->s3->rbuf.len=rr->length + SSL3_RT_HEADER_LENGTH + align;
373 s->packet= &(s->s3->rbuf.buf[0]);
374 }
375
376 if (rr->length > s->s3->rbuf.len - SSL3_RT_HEADER_LENGTH)
377 {
378 al=SSL_AD_RECORD_OVERFLOW;
379 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_PACKET_LENGTH_TOO_LONG);
380 goto f_err;
381 }
382
383 /* now s->rstate == SSL_ST_READ_BODY */
384 }
385
386 /* s->rstate == SSL_ST_READ_BODY, get and decode the data */
387
388 if (rr->length > s->packet_length-SSL3_RT_HEADER_LENGTH)
389 {
390 /* now s->packet_length == SSL3_RT_HEADER_LENGTH */
391 i=rr->length;
392 n=ssl3_read_n(s,i,i,1);
393 if (n <= 0) return(n); /* error or non-blocking io */
394 /* now n == rr->length,
395 * and s->packet_length == SSL3_RT_HEADER_LENGTH + rr->length */
396 }
397
398 s->rstate=SSL_ST_READ_HEADER; /* set state for later operations */
399
400 /* At this point, s->packet_length == SSL3_RT_HEADER_LNGTH + rr->length,
401 * and we have that many bytes in s->packet
402 */
403 rr->input= &(s->packet[SSL3_RT_HEADER_LENGTH]);
404
405 /* ok, we can now read from 's->packet' data into 'rr'
406 * rr->input points at rr->length bytes, which
407 * need to be copied into rr->data by either
408 * the decryption or by the decompression
409 * When the data is 'copied' into the rr->data buffer,
410 * rr->input will be pointed at the new buffer */
411
412 /* We now have - encrypted [ MAC [ compressed [ plain ] ] ]
413 * rr->length bytes of encrypted compressed stuff. */
414
415 /* check is not needed I believe */
416 if (rr->length > SSL3_RT_MAX_ENCRYPTED_LENGTH+extra)
417 {
418 al=SSL_AD_RECORD_OVERFLOW;
419 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_ENCRYPTED_LENGTH_TOO_LONG);
420 goto f_err;
421 }
422
423 /* decrypt in place in 'rr->input' */
424 rr->data=rr->input;
425
426 enc_err = s->method->ssl3_enc->enc(s,0);
427 if (enc_err <= 0)
428 {
429 if (enc_err == 0)
430 /* SSLerr() and ssl3_send_alert() have been called */
431 goto err;
432
433 /* Otherwise enc_err == -1, which indicates bad padding
434 * (rec->length has not been changed in this case).
435 * To minimize information leaked via timing, we will perform
436 * the MAC computation anyway. */
437 decryption_failed_or_bad_record_mac = 1;
438 }
439
440 #ifdef TLS_DEBUG
441 printf("dec %d\n",rr->length);
442 { unsigned int z; for (z=0; z<rr->length; z++) printf("%02X%c",rr->data[z],((z+1)%16)?' ':'\n'); }
443 printf("\n");
444 #endif
445
446 /* r->length is now the compressed data plus mac */
447 if ( (sess == NULL) ||
448 (s->enc_read_ctx == NULL) ||
449 (EVP_MD_CTX_md(s->read_hash) == NULL))
450 clear=1;
451
452 if (!clear)
453 {
454 /* !clear => s->read_hash != NULL => mac_size != -1 */
455 mac_size=EVP_MD_CTX_size(s->read_hash);
456 OPENSSL_assert(mac_size >= 0);
457
458 if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH+extra+mac_size)
459 {
460 #if 0 /* OK only for stream ciphers (then rr->length is visible from ciphertext anyway) */
461 al=SSL_AD_RECORD_OVERFLOW;
462 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_PRE_MAC_LENGTH_TOO_LONG);
463 goto f_err;
464 #else
465 decryption_failed_or_bad_record_mac = 1;
466 #endif
467 }
468 /* check the MAC for rr->input (it's in mac_size bytes at the tail) */
469 if (rr->length >= (unsigned int)mac_size)
470 {
471 rr->length -= mac_size;
472 mac = &rr->data[rr->length];
473 }
474 else
475 {
476 /* record (minus padding) is too short to contain a MAC */
477 #if 0 /* OK only for stream ciphers */
478 al=SSL_AD_DECODE_ERROR;
479 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_LENGTH_TOO_SHORT);
480 goto f_err;
481 #else
482 decryption_failed_or_bad_record_mac = 1;
483 rr->length = 0;
484 #endif
485 }
486 i=s->method->ssl3_enc->mac(s,md,0);
487 if (i < 0 || mac == NULL || memcmp(md, mac, (size_t)mac_size) != 0)
488 {
489 decryption_failed_or_bad_record_mac = 1;
490 }
491 }
492
493 if (decryption_failed_or_bad_record_mac)
494 {
495 /* A separate 'decryption_failed' alert was introduced with TLS 1.0,
496 * SSL 3.0 only has 'bad_record_mac'. But unless a decryption
497 * failure is directly visible from the ciphertext anyway,
498 * we should not reveal which kind of error occured -- this
499 * might become visible to an attacker (e.g. via a logfile) */
500 al=SSL_AD_BAD_RECORD_MAC;
501 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_DECRYPTION_FAILED_OR_BAD_RECORD_MAC);
502 goto f_err;
503 }
504
505 /* r->length is now just compressed */
506 if (s->expand != NULL)
507 {
508 if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH+extra)
509 {
510 al=SSL_AD_RECORD_OVERFLOW;
511 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_COMPRESSED_LENGTH_TOO_LONG);
512 goto f_err;
513 }
514 if (!ssl3_do_uncompress(s))
515 {
516 al=SSL_AD_DECOMPRESSION_FAILURE;
517 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_BAD_DECOMPRESSION);
518 goto f_err;
519 }
520 }
521
522 if (rr->length > SSL3_RT_MAX_PLAIN_LENGTH+extra)
523 {
524 al=SSL_AD_RECORD_OVERFLOW;
525 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_DATA_LENGTH_TOO_LONG);
526 goto f_err;
527 }
528
529 rr->off=0;
530 /* So at this point the following is true
531 * ssl->s3->rrec.type is the type of record
532 * ssl->s3->rrec.length == number of bytes in record
533 * ssl->s3->rrec.off == offset to first valid byte
534 * ssl->s3->rrec.data == where to take bytes from, increment
535 * after use :-).
536 */
537
538 /* we have pulled in a full packet so zero things */
539 s->packet_length=0;
540
541 /* just read a 0 length packet */
542 if (rr->length == 0) goto again;
543
544 #if 0
545 fprintf(stderr, "Ultimate Record type=%d, Length=%d\n", rr->type, rr->length);
546 #endif
547
548 return(1);
549
550 f_err:
551 ssl3_send_alert(s,SSL3_AL_FATAL,al);
552 err:
553 return(ret);
554 }
555
ssl3_do_uncompress(SSL * ssl)556 int ssl3_do_uncompress(SSL *ssl)
557 {
558 #ifndef OPENSSL_NO_COMP
559 int i;
560 SSL3_RECORD *rr;
561
562 rr= &(ssl->s3->rrec);
563 i=COMP_expand_block(ssl->expand,rr->comp,
564 SSL3_RT_MAX_PLAIN_LENGTH,rr->data,(int)rr->length);
565 if (i < 0)
566 return(0);
567 else
568 rr->length=i;
569 rr->data=rr->comp;
570 #endif
571 return(1);
572 }
573
ssl3_do_compress(SSL * ssl)574 int ssl3_do_compress(SSL *ssl)
575 {
576 #ifndef OPENSSL_NO_COMP
577 int i;
578 SSL3_RECORD *wr;
579
580 wr= &(ssl->s3->wrec);
581 i=COMP_compress_block(ssl->compress,wr->data,
582 SSL3_RT_MAX_COMPRESSED_LENGTH,
583 wr->input,(int)wr->length);
584 if (i < 0)
585 return(0);
586 else
587 wr->length=i;
588
589 wr->input=wr->data;
590 #endif
591 return(1);
592 }
593
594 /* Call this to write data in records of type 'type'
595 * It will return <= 0 if not all data has been sent or non-blocking IO.
596 */
ssl3_write_bytes(SSL * s,int type,const void * buf_,int len)597 int ssl3_write_bytes(SSL *s, int type, const void *buf_, int len)
598 {
599 const unsigned char *buf=buf_;
600 unsigned int tot,n,nw;
601 int i;
602 unsigned int max_plain_length;
603
604 s->rwstate=SSL_NOTHING;
605 tot=s->s3->wnum;
606 s->s3->wnum=0;
607
608 if (SSL_in_init(s) && !s->in_handshake)
609 {
610 i=s->handshake_func(s);
611 if (i < 0) return(i);
612 if (i == 0)
613 {
614 SSLerr(SSL_F_SSL3_WRITE_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
615 return -1;
616 }
617 }
618
619 n=(len-tot);
620 for (;;)
621 {
622 if (type == SSL3_RT_APPLICATION_DATA && (SSL_get_mode(s) & SSL_MODE_SMALL_BUFFERS))
623 max_plain_length = SSL3_RT_DEFAULT_PLAIN_LENGTH;
624 else
625 max_plain_length = s->max_send_fragment;
626
627 if (n > max_plain_length)
628 nw = max_plain_length;
629 else
630 nw=n;
631
632 i=do_ssl3_write(s, type, &(buf[tot]), nw, 0);
633 if (i <= 0)
634 {
635 s->s3->wnum=tot;
636 return i;
637 }
638
639 if ((i == (int)n) ||
640 (type == SSL3_RT_APPLICATION_DATA &&
641 (s->mode & SSL_MODE_ENABLE_PARTIAL_WRITE)))
642 {
643 /* next chunk of data should get another prepended empty fragment
644 * in ciphersuites with known-IV weakness: */
645 s->s3->empty_fragment_done = 0;
646
647 return tot+i;
648 }
649
650 n-=i;
651 tot+=i;
652 }
653 }
654
do_ssl3_write(SSL * s,int type,const unsigned char * buf,unsigned int len,int create_empty_fragment)655 static int do_ssl3_write(SSL *s, int type, const unsigned char *buf,
656 unsigned int len, int create_empty_fragment)
657 {
658 unsigned char *p,*plen;
659 int i,mac_size,clear=0;
660 int prefix_len=0;
661 int eivlen;
662 long align=0;
663 SSL3_RECORD *wr;
664 SSL3_BUFFER *wb=&(s->s3->wbuf);
665 SSL_SESSION *sess;
666
667 if (wb->buf == NULL)
668 if (!ssl3_setup_write_buffer(s))
669 return -1;
670
671 /* first check if there is a SSL3_BUFFER still being written
672 * out. This will happen with non blocking IO */
673 if (wb->left != 0)
674 return(ssl3_write_pending(s,type,buf,len));
675
676 /* If we have an alert to send, lets send it */
677 if (s->s3->alert_dispatch)
678 {
679 i=s->method->ssl_dispatch_alert(s);
680 if (i <= 0)
681 return(i);
682 /* if it went, fall through and send more stuff */
683 }
684
685 if (len == 0 && !create_empty_fragment)
686 return 0;
687
688 wr= &(s->s3->wrec);
689 sess=s->session;
690
691 if ( (sess == NULL) ||
692 (s->enc_write_ctx == NULL) ||
693 (EVP_MD_CTX_md(s->write_hash) == NULL))
694 {
695 #if 1
696 clear=s->enc_write_ctx?0:1; /* must be AEAD cipher */
697 #else
698 clear=1;
699 #endif
700 mac_size=0;
701 }
702 else
703 {
704 mac_size=EVP_MD_CTX_size(s->write_hash);
705 if (mac_size < 0)
706 goto err;
707 }
708
709 /* 'create_empty_fragment' is true only when this function calls itself */
710 if (!clear && !create_empty_fragment && !s->s3->empty_fragment_done)
711 {
712 /* countermeasure against known-IV weakness in CBC ciphersuites
713 * (see http://www.openssl.org/~bodo/tls-cbc.txt) */
714
715 if (s->s3->need_empty_fragments && type == SSL3_RT_APPLICATION_DATA)
716 {
717 /* recursive function call with 'create_empty_fragment' set;
718 * this prepares and buffers the data for an empty fragment
719 * (these 'prefix_len' bytes are sent out later
720 * together with the actual payload) */
721 prefix_len = do_ssl3_write(s, type, buf, 0, 1);
722 if (prefix_len <= 0)
723 goto err;
724
725 if (prefix_len >
726 (SSL3_RT_HEADER_LENGTH + SSL3_RT_SEND_MAX_ENCRYPTED_OVERHEAD))
727 {
728 /* insufficient space */
729 SSLerr(SSL_F_DO_SSL3_WRITE, ERR_R_INTERNAL_ERROR);
730 goto err;
731 }
732 }
733
734 s->s3->empty_fragment_done = 1;
735 }
736
737 /* resize if necessary to hold the data. */
738 if (len + SSL3_RT_DEFAULT_WRITE_OVERHEAD > wb->len)
739 {
740 if ((p=OPENSSL_realloc(wb->buf, len + SSL3_RT_DEFAULT_WRITE_OVERHEAD))==NULL)
741 {
742 SSLerr(SSL_F_DO_SSL3_WRITE,ERR_R_MALLOC_FAILURE);
743 goto err;
744 }
745 wb->buf = p;
746 wb->len = len + SSL3_RT_DEFAULT_WRITE_OVERHEAD;
747 }
748
749 if (create_empty_fragment)
750 {
751 #if defined(SSL3_ALIGN_PAYLOAD) && SSL3_ALIGN_PAYLOAD!=0
752 /* extra fragment would be couple of cipher blocks,
753 * which would be multiple of SSL3_ALIGN_PAYLOAD, so
754 * if we want to align the real payload, then we can
755 * just pretent we simply have two headers. */
756 align = (long)wb->buf + 2*SSL3_RT_HEADER_LENGTH;
757 align = (-align)&(SSL3_ALIGN_PAYLOAD-1);
758 #endif
759 p = wb->buf + align;
760 wb->offset = align;
761 }
762 else if (prefix_len)
763 {
764 p = wb->buf + wb->offset + prefix_len;
765 }
766 else
767 {
768 #if defined(SSL3_ALIGN_PAYLOAD) && SSL3_ALIGN_PAYLOAD!=0
769 align = (long)wb->buf + SSL3_RT_HEADER_LENGTH;
770 align = (-align)&(SSL3_ALIGN_PAYLOAD-1);
771 #endif
772 p = wb->buf + align;
773 wb->offset = align;
774 }
775
776 /* write the header */
777
778 *(p++)=type&0xff;
779 wr->type=type;
780
781 *(p++)=(s->version>>8);
782 /* Some servers hang if iniatial client hello is larger than 256
783 * bytes and record version number > TLS 1.0
784 */
785 if (s->state == SSL3_ST_CW_CLNT_HELLO_B
786 && TLS1_get_version(s) > TLS1_VERSION)
787 *(p++) = 0x1;
788 else
789 *(p++)=s->version&0xff;
790
791 /* field where we are to write out packet length */
792 plen=p;
793 p+=2;
794 /* Explicit IV length, block ciphers and TLS version 1.1 or later */
795 if (s->enc_write_ctx && s->version >= TLS1_1_VERSION)
796 {
797 int mode = EVP_CIPHER_CTX_mode(s->enc_write_ctx);
798 if (mode == EVP_CIPH_CBC_MODE)
799 {
800 eivlen = EVP_CIPHER_CTX_iv_length(s->enc_write_ctx);
801 if (eivlen <= 1)
802 eivlen = 0;
803 }
804 /* Need explicit part of IV for GCM mode */
805 else if (mode == EVP_CIPH_GCM_MODE)
806 eivlen = EVP_GCM_TLS_EXPLICIT_IV_LEN;
807 else
808 eivlen = 0;
809 }
810 else
811 eivlen = 0;
812
813 /* lets setup the record stuff. */
814 wr->data=p + eivlen;
815 wr->length=(int)len;
816 wr->input=(unsigned char *)buf;
817
818 /* we now 'read' from wr->input, wr->length bytes into
819 * wr->data */
820
821 /* first we compress */
822 if (s->compress != NULL)
823 {
824 if (!ssl3_do_compress(s))
825 {
826 SSLerr(SSL_F_DO_SSL3_WRITE,SSL_R_COMPRESSION_FAILURE);
827 goto err;
828 }
829 }
830 else
831 {
832 memcpy(wr->data,wr->input,wr->length);
833 wr->input=wr->data;
834 }
835
836 /* we should still have the output to wr->data and the input
837 * from wr->input. Length should be wr->length.
838 * wr->data still points in the wb->buf */
839
840 if (mac_size != 0)
841 {
842 if (s->method->ssl3_enc->mac(s,&(p[wr->length + eivlen]),1) < 0)
843 goto err;
844 wr->length+=mac_size;
845 }
846
847 wr->input=p;
848 wr->data=p;
849
850 if (eivlen)
851 {
852 /* if (RAND_pseudo_bytes(p, eivlen) <= 0)
853 goto err; */
854 wr->length += eivlen;
855 }
856
857 /* ssl3_enc can only have an error on read */
858 s->method->ssl3_enc->enc(s,1);
859
860 /* record length after mac and block padding */
861 s2n(wr->length,plen);
862
863 /* we should now have
864 * wr->data pointing to the encrypted data, which is
865 * wr->length long */
866 wr->type=type; /* not needed but helps for debugging */
867 wr->length+=SSL3_RT_HEADER_LENGTH;
868
869 if (create_empty_fragment)
870 {
871 /* we are in a recursive call;
872 * just return the length, don't write out anything here
873 */
874 return wr->length;
875 }
876
877 /* now let's set up wb */
878 wb->left = prefix_len + wr->length;
879
880 /* memorize arguments so that ssl3_write_pending can detect bad write retries later */
881 s->s3->wpend_tot=len;
882 s->s3->wpend_buf=buf;
883 s->s3->wpend_type=type;
884 s->s3->wpend_ret=len;
885
886 /* we now just need to write the buffer */
887 return ssl3_write_pending(s,type,buf,len);
888 err:
889 return -1;
890 }
891
892 /* if s->s3->wbuf.left != 0, we need to call this */
ssl3_write_pending(SSL * s,int type,const unsigned char * buf,unsigned int len)893 int ssl3_write_pending(SSL *s, int type, const unsigned char *buf,
894 unsigned int len)
895 {
896 int i;
897 SSL3_BUFFER *wb=&(s->s3->wbuf);
898
899 /* XXXX */
900 if ((s->s3->wpend_tot > (int)len)
901 || ((s->s3->wpend_buf != buf) &&
902 !(s->mode & SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER))
903 || (s->s3->wpend_type != type))
904 {
905 SSLerr(SSL_F_SSL3_WRITE_PENDING,SSL_R_BAD_WRITE_RETRY);
906 return(-1);
907 }
908
909 for (;;)
910 {
911 clear_sys_error();
912 if (s->wbio != NULL)
913 {
914 s->rwstate=SSL_WRITING;
915 i=BIO_write(s->wbio,
916 (char *)&(wb->buf[wb->offset]),
917 (unsigned int)wb->left);
918 }
919 else
920 {
921 SSLerr(SSL_F_SSL3_WRITE_PENDING,SSL_R_BIO_NOT_SET);
922 i= -1;
923 }
924 if (i == wb->left)
925 {
926 wb->left=0;
927 wb->offset+=i;
928 if (s->mode & SSL_MODE_RELEASE_BUFFERS &&
929 SSL_version(s) != DTLS1_VERSION && SSL_version(s) != DTLS1_BAD_VER)
930 ssl3_release_write_buffer(s);
931 s->rwstate=SSL_NOTHING;
932 return(s->s3->wpend_ret);
933 }
934 else if (i <= 0) {
935 if (s->version == DTLS1_VERSION ||
936 s->version == DTLS1_BAD_VER) {
937 /* For DTLS, just drop it. That's kind of the whole
938 point in using a datagram service */
939 wb->left = 0;
940 }
941 return(i);
942 }
943 wb->offset+=i;
944 wb->left-=i;
945 }
946 }
947
948 /* Return up to 'len' payload bytes received in 'type' records.
949 * 'type' is one of the following:
950 *
951 * - SSL3_RT_HANDSHAKE (when ssl3_get_message calls us)
952 * - SSL3_RT_APPLICATION_DATA (when ssl3_read calls us)
953 * - 0 (during a shutdown, no data has to be returned)
954 *
955 * If we don't have stored data to work from, read a SSL/TLS record first
956 * (possibly multiple records if we still don't have anything to return).
957 *
958 * This function must handle any surprises the peer may have for us, such as
959 * Alert records (e.g. close_notify), ChangeCipherSpec records (not really
960 * a surprise, but handled as if it were), or renegotiation requests.
961 * Also if record payloads contain fragments too small to process, we store
962 * them until there is enough for the respective protocol (the record protocol
963 * may use arbitrary fragmentation and even interleaving):
964 * Change cipher spec protocol
965 * just 1 byte needed, no need for keeping anything stored
966 * Alert protocol
967 * 2 bytes needed (AlertLevel, AlertDescription)
968 * Handshake protocol
969 * 4 bytes needed (HandshakeType, uint24 length) -- we just have
970 * to detect unexpected Client Hello and Hello Request messages
971 * here, anything else is handled by higher layers
972 * Application data protocol
973 * none of our business
974 */
ssl3_read_bytes(SSL * s,int type,unsigned char * buf,int len,int peek)975 int ssl3_read_bytes(SSL *s, int type, unsigned char *buf, int len, int peek)
976 {
977 int al,i,j,ret;
978 unsigned int n;
979 SSL3_RECORD *rr;
980 void (*cb)(const SSL *ssl,int type2,int val)=NULL;
981
982 if (s->s3->rbuf.buf == NULL) /* Not initialized yet */
983 if (!ssl3_setup_read_buffer(s))
984 return(-1);
985
986 if ((type && (type != SSL3_RT_APPLICATION_DATA) && (type != SSL3_RT_HANDSHAKE) && type) ||
987 (peek && (type != SSL3_RT_APPLICATION_DATA)))
988 {
989 SSLerr(SSL_F_SSL3_READ_BYTES, ERR_R_INTERNAL_ERROR);
990 return -1;
991 }
992
993 if ((type == SSL3_RT_HANDSHAKE) && (s->s3->handshake_fragment_len > 0))
994 /* (partially) satisfy request from storage */
995 {
996 unsigned char *src = s->s3->handshake_fragment;
997 unsigned char *dst = buf;
998 unsigned int k;
999
1000 /* peek == 0 */
1001 n = 0;
1002 while ((len > 0) && (s->s3->handshake_fragment_len > 0))
1003 {
1004 *dst++ = *src++;
1005 len--; s->s3->handshake_fragment_len--;
1006 n++;
1007 }
1008 /* move any remaining fragment bytes: */
1009 for (k = 0; k < s->s3->handshake_fragment_len; k++)
1010 s->s3->handshake_fragment[k] = *src++;
1011 return n;
1012 }
1013
1014 /* Now s->s3->handshake_fragment_len == 0 if type == SSL3_RT_HANDSHAKE. */
1015
1016 if (!s->in_handshake && SSL_in_init(s))
1017 {
1018 /* type == SSL3_RT_APPLICATION_DATA */
1019 i=s->handshake_func(s);
1020 if (i < 0) return(i);
1021 if (i == 0)
1022 {
1023 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
1024 return(-1);
1025 }
1026 }
1027 start:
1028 s->rwstate=SSL_NOTHING;
1029
1030 /* s->s3->rrec.type - is the type of record
1031 * s->s3->rrec.data, - data
1032 * s->s3->rrec.off, - offset into 'data' for next read
1033 * s->s3->rrec.length, - number of bytes. */
1034 rr = &(s->s3->rrec);
1035
1036 /* get new packet if necessary */
1037 if ((rr->length == 0) || (s->rstate == SSL_ST_READ_BODY))
1038 {
1039 ret=ssl3_get_record(s);
1040 if (ret <= 0) return(ret);
1041 }
1042
1043 /* we now have a packet which can be read and processed */
1044
1045 if (s->s3->change_cipher_spec /* set when we receive ChangeCipherSpec,
1046 * reset by ssl3_get_finished */
1047 && (rr->type != SSL3_RT_HANDSHAKE))
1048 {
1049 al=SSL_AD_UNEXPECTED_MESSAGE;
1050 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_DATA_BETWEEN_CCS_AND_FINISHED);
1051 goto f_err;
1052 }
1053
1054 /* If the other end has shut down, throw anything we read away
1055 * (even in 'peek' mode) */
1056 if (s->shutdown & SSL_RECEIVED_SHUTDOWN)
1057 {
1058 rr->length=0;
1059 s->rwstate=SSL_NOTHING;
1060 return(0);
1061 }
1062
1063
1064 if (type == rr->type) /* SSL3_RT_APPLICATION_DATA or SSL3_RT_HANDSHAKE */
1065 {
1066 /* make sure that we are not getting application data when we
1067 * are doing a handshake for the first time */
1068 if (SSL_in_init(s) && (type == SSL3_RT_APPLICATION_DATA) &&
1069 (s->enc_read_ctx == NULL))
1070 {
1071 al=SSL_AD_UNEXPECTED_MESSAGE;
1072 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_APP_DATA_IN_HANDSHAKE);
1073 goto f_err;
1074 }
1075
1076 if (len <= 0) return(len);
1077
1078 if ((unsigned int)len > rr->length)
1079 n = rr->length;
1080 else
1081 n = (unsigned int)len;
1082
1083 memcpy(buf,&(rr->data[rr->off]),n);
1084 if (!peek)
1085 {
1086 rr->length-=n;
1087 rr->off+=n;
1088 if (rr->length == 0)
1089 {
1090 s->rstate=SSL_ST_READ_HEADER;
1091 rr->off=0;
1092 if (s->mode & SSL_MODE_RELEASE_BUFFERS)
1093 ssl3_release_read_buffer(s);
1094 }
1095 }
1096 return(n);
1097 }
1098
1099
1100 /* If we get here, then type != rr->type; if we have a handshake
1101 * message, then it was unexpected (Hello Request or Client Hello). */
1102
1103 /* In case of record types for which we have 'fragment' storage,
1104 * fill that so that we can process the data at a fixed place.
1105 */
1106 {
1107 unsigned int dest_maxlen = 0;
1108 unsigned char *dest = NULL;
1109 unsigned int *dest_len = NULL;
1110
1111 if (rr->type == SSL3_RT_HANDSHAKE)
1112 {
1113 dest_maxlen = sizeof s->s3->handshake_fragment;
1114 dest = s->s3->handshake_fragment;
1115 dest_len = &s->s3->handshake_fragment_len;
1116 }
1117 else if (rr->type == SSL3_RT_ALERT)
1118 {
1119 dest_maxlen = sizeof s->s3->alert_fragment;
1120 dest = s->s3->alert_fragment;
1121 dest_len = &s->s3->alert_fragment_len;
1122 }
1123 #ifndef OPENSSL_NO_HEARTBEATS
1124 else if (rr->type == TLS1_RT_HEARTBEAT)
1125 {
1126 tls1_process_heartbeat(s);
1127
1128 /* Exit and notify application to read again */
1129 rr->length = 0;
1130 s->rwstate=SSL_READING;
1131 BIO_clear_retry_flags(SSL_get_rbio(s));
1132 BIO_set_retry_read(SSL_get_rbio(s));
1133 return(-1);
1134 }
1135 #endif
1136
1137 if (dest_maxlen > 0)
1138 {
1139 n = dest_maxlen - *dest_len; /* available space in 'dest' */
1140 if (rr->length < n)
1141 n = rr->length; /* available bytes */
1142
1143 /* now move 'n' bytes: */
1144 while (n-- > 0)
1145 {
1146 dest[(*dest_len)++] = rr->data[rr->off++];
1147 rr->length--;
1148 }
1149
1150 if (*dest_len < dest_maxlen)
1151 goto start; /* fragment was too small */
1152 }
1153 }
1154
1155 /* s->s3->handshake_fragment_len == 4 iff rr->type == SSL3_RT_HANDSHAKE;
1156 * s->s3->alert_fragment_len == 2 iff rr->type == SSL3_RT_ALERT.
1157 * (Possibly rr is 'empty' now, i.e. rr->length may be 0.) */
1158
1159 /* If we are a client, check for an incoming 'Hello Request': */
1160 if ((!s->server) &&
1161 (s->s3->handshake_fragment_len >= 4) &&
1162 (s->s3->handshake_fragment[0] == SSL3_MT_HELLO_REQUEST) &&
1163 (s->session != NULL) && (s->session->cipher != NULL))
1164 {
1165 s->s3->handshake_fragment_len = 0;
1166
1167 if ((s->s3->handshake_fragment[1] != 0) ||
1168 (s->s3->handshake_fragment[2] != 0) ||
1169 (s->s3->handshake_fragment[3] != 0))
1170 {
1171 al=SSL_AD_DECODE_ERROR;
1172 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_BAD_HELLO_REQUEST);
1173 goto f_err;
1174 }
1175
1176 if (s->msg_callback)
1177 s->msg_callback(0, s->version, SSL3_RT_HANDSHAKE, s->s3->handshake_fragment, 4, s, s->msg_callback_arg);
1178
1179 if (SSL_is_init_finished(s) &&
1180 !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS) &&
1181 !s->s3->renegotiate)
1182 {
1183 ssl3_renegotiate(s);
1184 if (ssl3_renegotiate_check(s))
1185 {
1186 i=s->handshake_func(s);
1187 if (i < 0) return(i);
1188 if (i == 0)
1189 {
1190 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
1191 return(-1);
1192 }
1193
1194 if (!(s->mode & SSL_MODE_AUTO_RETRY))
1195 {
1196 if (s->s3->rbuf.left == 0) /* no read-ahead left? */
1197 {
1198 BIO *bio;
1199 /* In the case where we try to read application data,
1200 * but we trigger an SSL handshake, we return -1 with
1201 * the retry option set. Otherwise renegotiation may
1202 * cause nasty problems in the blocking world */
1203 s->rwstate=SSL_READING;
1204 bio=SSL_get_rbio(s);
1205 BIO_clear_retry_flags(bio);
1206 BIO_set_retry_read(bio);
1207 return(-1);
1208 }
1209 }
1210 }
1211 }
1212 /* we either finished a handshake or ignored the request,
1213 * now try again to obtain the (application) data we were asked for */
1214 goto start;
1215 }
1216 /* If we are a server and get a client hello when renegotiation isn't
1217 * allowed send back a no renegotiation alert and carry on.
1218 * WARNING: experimental code, needs reviewing (steve)
1219 */
1220 if (s->server &&
1221 SSL_is_init_finished(s) &&
1222 !s->s3->send_connection_binding &&
1223 (s->version > SSL3_VERSION) &&
1224 (s->s3->handshake_fragment_len >= 4) &&
1225 (s->s3->handshake_fragment[0] == SSL3_MT_CLIENT_HELLO) &&
1226 (s->session != NULL) && (s->session->cipher != NULL) &&
1227 !(s->ctx->options & SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION))
1228
1229 {
1230 /*s->s3->handshake_fragment_len = 0;*/
1231 rr->length = 0;
1232 ssl3_send_alert(s,SSL3_AL_WARNING, SSL_AD_NO_RENEGOTIATION);
1233 goto start;
1234 }
1235 if (s->s3->alert_fragment_len >= 2)
1236 {
1237 int alert_level = s->s3->alert_fragment[0];
1238 int alert_descr = s->s3->alert_fragment[1];
1239
1240 s->s3->alert_fragment_len = 0;
1241
1242 if (s->msg_callback)
1243 s->msg_callback(0, s->version, SSL3_RT_ALERT, s->s3->alert_fragment, 2, s, s->msg_callback_arg);
1244
1245 if (s->info_callback != NULL)
1246 cb=s->info_callback;
1247 else if (s->ctx->info_callback != NULL)
1248 cb=s->ctx->info_callback;
1249
1250 if (cb != NULL)
1251 {
1252 j = (alert_level << 8) | alert_descr;
1253 cb(s, SSL_CB_READ_ALERT, j);
1254 }
1255
1256 if (alert_level == 1) /* warning */
1257 {
1258 s->s3->warn_alert = alert_descr;
1259 if (alert_descr == SSL_AD_CLOSE_NOTIFY)
1260 {
1261 s->shutdown |= SSL_RECEIVED_SHUTDOWN;
1262 return(0);
1263 }
1264 /* This is a warning but we receive it if we requested
1265 * renegotiation and the peer denied it. Terminate with
1266 * a fatal alert because if application tried to
1267 * renegotiatie it presumably had a good reason and
1268 * expects it to succeed.
1269 *
1270 * In future we might have a renegotiation where we
1271 * don't care if the peer refused it where we carry on.
1272 */
1273 else if (alert_descr == SSL_AD_NO_RENEGOTIATION)
1274 {
1275 al = SSL_AD_HANDSHAKE_FAILURE;
1276 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_NO_RENEGOTIATION);
1277 goto f_err;
1278 }
1279 #ifdef SSL_AD_MISSING_SRP_USERNAME
1280 if (alert_descr == SSL_AD_MISSING_SRP_USERNAME)
1281 return(0);
1282 #endif
1283 }
1284 else if (alert_level == 2) /* fatal */
1285 {
1286 char tmp[16];
1287
1288 s->rwstate=SSL_NOTHING;
1289 s->s3->fatal_alert = alert_descr;
1290 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_AD_REASON_OFFSET + alert_descr);
1291 BIO_snprintf(tmp,sizeof tmp,"%d",alert_descr);
1292 ERR_add_error_data(2,"SSL alert number ",tmp);
1293 s->shutdown|=SSL_RECEIVED_SHUTDOWN;
1294 SSL_CTX_remove_session(s->ctx,s->session);
1295 return(0);
1296 }
1297 else
1298 {
1299 al=SSL_AD_ILLEGAL_PARAMETER;
1300 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNKNOWN_ALERT_TYPE);
1301 goto f_err;
1302 }
1303
1304 goto start;
1305 }
1306
1307 if (s->shutdown & SSL_SENT_SHUTDOWN) /* but we have not received a shutdown */
1308 {
1309 s->rwstate=SSL_NOTHING;
1310 rr->length=0;
1311 return(0);
1312 }
1313
1314 if (rr->type == SSL3_RT_CHANGE_CIPHER_SPEC)
1315 {
1316 /* 'Change Cipher Spec' is just a single byte, so we know
1317 * exactly what the record payload has to look like */
1318 if ( (rr->length != 1) || (rr->off != 0) ||
1319 (rr->data[0] != SSL3_MT_CCS))
1320 {
1321 al=SSL_AD_ILLEGAL_PARAMETER;
1322 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_BAD_CHANGE_CIPHER_SPEC);
1323 goto f_err;
1324 }
1325
1326 /* Check we have a cipher to change to */
1327 if (s->s3->tmp.new_cipher == NULL)
1328 {
1329 al=SSL_AD_UNEXPECTED_MESSAGE;
1330 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_CCS_RECEIVED_EARLY);
1331 goto f_err;
1332 }
1333
1334 rr->length=0;
1335
1336 if (s->msg_callback)
1337 s->msg_callback(0, s->version, SSL3_RT_CHANGE_CIPHER_SPEC, rr->data, 1, s, s->msg_callback_arg);
1338
1339 s->s3->change_cipher_spec=1;
1340 if (!ssl3_do_change_cipher_spec(s))
1341 goto err;
1342 else
1343 goto start;
1344 }
1345
1346 /* Unexpected handshake message (Client Hello, or protocol violation) */
1347 if ((s->s3->handshake_fragment_len >= 4) && !s->in_handshake)
1348 {
1349 if (((s->state&SSL_ST_MASK) == SSL_ST_OK) &&
1350 !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS))
1351 {
1352 #if 0 /* worked only because C operator preferences are not as expected (and
1353 * because this is not really needed for clients except for detecting
1354 * protocol violations): */
1355 s->state=SSL_ST_BEFORE|(s->server)
1356 ?SSL_ST_ACCEPT
1357 :SSL_ST_CONNECT;
1358 #else
1359 s->state = s->server ? SSL_ST_ACCEPT : SSL_ST_CONNECT;
1360 #endif
1361 s->renegotiate=1;
1362 s->new_session=1;
1363 }
1364 i=s->handshake_func(s);
1365 if (i < 0) return(i);
1366 if (i == 0)
1367 {
1368 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
1369 return(-1);
1370 }
1371
1372 if (!(s->mode & SSL_MODE_AUTO_RETRY))
1373 {
1374 if (s->s3->rbuf.left == 0) /* no read-ahead left? */
1375 {
1376 BIO *bio;
1377 /* In the case where we try to read application data,
1378 * but we trigger an SSL handshake, we return -1 with
1379 * the retry option set. Otherwise renegotiation may
1380 * cause nasty problems in the blocking world */
1381 s->rwstate=SSL_READING;
1382 bio=SSL_get_rbio(s);
1383 BIO_clear_retry_flags(bio);
1384 BIO_set_retry_read(bio);
1385 return(-1);
1386 }
1387 }
1388 goto start;
1389 }
1390
1391 switch (rr->type)
1392 {
1393 default:
1394 #ifndef OPENSSL_NO_TLS
1395 /* TLS up to v1.1 just ignores unknown message types:
1396 * TLS v1.2 give an unexpected message alert.
1397 */
1398 if (s->version >= TLS1_VERSION && s->version <= TLS1_1_VERSION)
1399 {
1400 rr->length = 0;
1401 goto start;
1402 }
1403 #endif
1404 al=SSL_AD_UNEXPECTED_MESSAGE;
1405 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNEXPECTED_RECORD);
1406 goto f_err;
1407 case SSL3_RT_CHANGE_CIPHER_SPEC:
1408 case SSL3_RT_ALERT:
1409 case SSL3_RT_HANDSHAKE:
1410 /* we already handled all of these, with the possible exception
1411 * of SSL3_RT_HANDSHAKE when s->in_handshake is set, but that
1412 * should not happen when type != rr->type */
1413 al=SSL_AD_UNEXPECTED_MESSAGE;
1414 SSLerr(SSL_F_SSL3_READ_BYTES,ERR_R_INTERNAL_ERROR);
1415 goto f_err;
1416 case SSL3_RT_APPLICATION_DATA:
1417 /* At this point, we were expecting handshake data,
1418 * but have application data. If the library was
1419 * running inside ssl3_read() (i.e. in_read_app_data
1420 * is set) and it makes sense to read application data
1421 * at this point (session renegotiation not yet started),
1422 * we will indulge it.
1423 */
1424 if (s->s3->in_read_app_data &&
1425 (s->s3->total_renegotiations != 0) &&
1426 ((
1427 (s->state & SSL_ST_CONNECT) &&
1428 (s->state >= SSL3_ST_CW_CLNT_HELLO_A) &&
1429 (s->state <= SSL3_ST_CR_SRVR_HELLO_A)
1430 ) || (
1431 (s->state & SSL_ST_ACCEPT) &&
1432 (s->state <= SSL3_ST_SW_HELLO_REQ_A) &&
1433 (s->state >= SSL3_ST_SR_CLNT_HELLO_A)
1434 )
1435 ))
1436 {
1437 s->s3->in_read_app_data=2;
1438 return(-1);
1439 }
1440 else
1441 {
1442 al=SSL_AD_UNEXPECTED_MESSAGE;
1443 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNEXPECTED_RECORD);
1444 goto f_err;
1445 }
1446 }
1447 /* not reached */
1448
1449 f_err:
1450 ssl3_send_alert(s,SSL3_AL_FATAL,al);
1451 err:
1452 return(-1);
1453 }
1454
ssl3_do_change_cipher_spec(SSL * s)1455 int ssl3_do_change_cipher_spec(SSL *s)
1456 {
1457 int i;
1458 const char *sender;
1459 int slen;
1460
1461 if (s->state & SSL_ST_ACCEPT)
1462 i=SSL3_CHANGE_CIPHER_SERVER_READ;
1463 else
1464 i=SSL3_CHANGE_CIPHER_CLIENT_READ;
1465
1466 if (s->s3->tmp.key_block == NULL)
1467 {
1468 if (s->session == NULL)
1469 {
1470 /* might happen if dtls1_read_bytes() calls this */
1471 SSLerr(SSL_F_SSL3_DO_CHANGE_CIPHER_SPEC,SSL_R_CCS_RECEIVED_EARLY);
1472 return (0);
1473 }
1474
1475 s->session->cipher=s->s3->tmp.new_cipher;
1476 if (!s->method->ssl3_enc->setup_key_block(s)) return(0);
1477 }
1478
1479 if (!s->method->ssl3_enc->change_cipher_state(s,i))
1480 return(0);
1481
1482 /* we have to record the message digest at
1483 * this point so we can get it before we read
1484 * the finished message */
1485 if (s->state & SSL_ST_CONNECT)
1486 {
1487 sender=s->method->ssl3_enc->server_finished_label;
1488 slen=s->method->ssl3_enc->server_finished_label_len;
1489 }
1490 else
1491 {
1492 sender=s->method->ssl3_enc->client_finished_label;
1493 slen=s->method->ssl3_enc->client_finished_label_len;
1494 }
1495
1496 s->s3->tmp.peer_finish_md_len = s->method->ssl3_enc->final_finish_mac(s,
1497 sender,slen,s->s3->tmp.peer_finish_md);
1498
1499 return(1);
1500 }
1501
ssl3_send_alert(SSL * s,int level,int desc)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
ssl3_dispatch_alert(SSL * s)1523 int ssl3_dispatch_alert(SSL *s)
1524 {
1525 int i,j;
1526 void (*cb)(const SSL *ssl,int type,int val)=NULL;
1527
1528 s->s3->alert_dispatch=0;
1529 i = do_ssl3_write(s, SSL3_RT_ALERT, &s->s3->send_alert[0], 2, 0);
1530 if (i <= 0)
1531 {
1532 s->s3->alert_dispatch=1;
1533 }
1534 else
1535 {
1536 /* Alert sent to BIO. If it is important, flush it now.
1537 * If the message does not get sent due to non-blocking IO,
1538 * we will not worry too much. */
1539 if (s->s3->send_alert[0] == SSL3_AL_FATAL)
1540 (void)BIO_flush(s->wbio);
1541
1542 if (s->msg_callback)
1543 s->msg_callback(1, s->version, SSL3_RT_ALERT, s->s3->send_alert, 2, s, s->msg_callback_arg);
1544
1545 if (s->info_callback != NULL)
1546 cb=s->info_callback;
1547 else if (s->ctx->info_callback != NULL)
1548 cb=s->ctx->info_callback;
1549
1550 if (cb != NULL)
1551 {
1552 j=(s->s3->send_alert[0]<<8)|s->s3->send_alert[1];
1553 cb(s,SSL_CB_WRITE_ALERT,j);
1554 }
1555 }
1556 return(i);
1557 }
1558