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
119 static int do_ssl3_write(SSL *s, int type, const unsigned char *buf,
120 unsigned int len, int create_empty_fragment);
121 static int ssl3_get_record(SSL *s);
122
ssl3_read_n(SSL * s,int n,int max,int extend)123 int ssl3_read_n(SSL *s, int n, int max, int extend)
124 {
125 /* If extend == 0, obtain new n-byte packet; if extend == 1, increase
126 * packet by another n bytes.
127 * The packet will be in the sub-array of s->s3->rbuf.buf specified
128 * by s->packet and s->packet_length.
129 * (If s->read_ahead is set, 'max' bytes may be stored in rbuf
130 * [plus s->packet_length bytes if extend == 1].)
131 */
132 int i,len,left;
133 long align=0;
134 unsigned char *pkt;
135 SSL3_BUFFER *rb;
136
137 if (n <= 0) return n;
138
139 rb = &(s->s3->rbuf);
140 if (rb->buf == NULL)
141 if (!ssl3_setup_read_buffer(s))
142 return -1;
143
144 left = rb->left;
145 #if defined(SSL3_ALIGN_PAYLOAD) && SSL3_ALIGN_PAYLOAD!=0
146 align = (long)rb->buf + SSL3_RT_HEADER_LENGTH;
147 align = (-align)&(SSL3_ALIGN_PAYLOAD-1);
148 #endif
149
150 if (!extend)
151 {
152 /* start with empty packet ... */
153 if (left == 0)
154 rb->offset = align;
155 else if (align != 0 && left >= SSL3_RT_HEADER_LENGTH)
156 {
157 /* check if next packet length is large
158 * enough to justify payload alignment... */
159 pkt = rb->buf + rb->offset;
160 if (pkt[0] == SSL3_RT_APPLICATION_DATA
161 && (pkt[3]<<8|pkt[4]) >= 128)
162 {
163 /* Note that even if packet is corrupted
164 * and its length field is insane, we can
165 * only be led to wrong decision about
166 * whether memmove will occur or not.
167 * Header values has no effect on memmove
168 * arguments and therefore no buffer
169 * overrun can be triggered. */
170 memmove (rb->buf+align,pkt,left);
171 rb->offset = align;
172 }
173 }
174 s->packet = rb->buf + rb->offset;
175 s->packet_length = 0;
176 /* ... now we can act as if 'extend' was set */
177 }
178
179 /* For DTLS/UDP reads should not span multiple packets
180 * because the read operation returns the whole packet
181 * at once (as long as it fits into the buffer). */
182 if (SSL_version(s) == DTLS1_VERSION || SSL_version(s) == DTLS1_BAD_VER)
183 {
184 if (left > 0 && n > left)
185 n = left;
186 }
187
188 /* if there is enough in the buffer from a previous read, take some */
189 if (left >= n)
190 {
191 s->packet_length+=n;
192 rb->left=left-n;
193 rb->offset+=n;
194 return(n);
195 }
196
197 /* else we need to read more data */
198
199 len = s->packet_length;
200 pkt = rb->buf+align;
201 /* Move any available bytes to front of buffer:
202 * 'len' bytes already pointed to by 'packet',
203 * 'left' extra ones at the end */
204 if (s->packet != pkt) /* len > 0 */
205 {
206 memmove(pkt, s->packet, len+left);
207 s->packet = pkt;
208 rb->offset = len + align;
209 }
210
211 if (n > (int)(rb->len - rb->offset)) /* does not happen */
212 {
213 SSLerr(SSL_F_SSL3_READ_N,ERR_R_INTERNAL_ERROR);
214 return -1;
215 }
216
217 if (!s->read_ahead)
218 /* ignore max parameter */
219 max = n;
220 else
221 {
222 if (max < n)
223 max = n;
224 if (max > (int)(rb->len - rb->offset))
225 max = rb->len - rb->offset;
226 }
227
228 while (left < n)
229 {
230 /* Now we have len+left bytes at the front of s->s3->rbuf.buf
231 * and need to read in more until we have len+n (up to
232 * len+max if possible) */
233
234 clear_sys_error();
235 if (s->rbio != NULL)
236 {
237 s->rwstate=SSL_READING;
238 i=BIO_read(s->rbio,pkt+len+left, max-left);
239 }
240 else
241 {
242 SSLerr(SSL_F_SSL3_READ_N,SSL_R_READ_BIO_NOT_SET);
243 i = -1;
244 }
245
246 if (i <= 0)
247 {
248 rb->left = left;
249 if (s->mode & SSL_MODE_RELEASE_BUFFERS &&
250 SSL_version(s) != DTLS1_VERSION && SSL_version(s) != DTLS1_BAD_VER)
251 if (len+left == 0)
252 ssl3_release_read_buffer(s);
253 return(i);
254 }
255 left+=i;
256 /* reads should *never* span multiple packets for DTLS because
257 * the underlying transport protocol is message oriented as opposed
258 * to byte oriented as in the TLS case. */
259 if (SSL_version(s) == DTLS1_VERSION || SSL_version(s) == DTLS1_BAD_VER)
260 {
261 if (n > left)
262 n = left; /* makes the while condition false */
263 }
264 }
265
266 /* done reading, now the book-keeping */
267 rb->offset += n;
268 rb->left = left - n;
269 s->packet_length += n;
270 s->rwstate=SSL_NOTHING;
271 return(n);
272 }
273
274 /* Call this to get a new input record.
275 * It will return <= 0 if more data is needed, normally due to an error
276 * or non-blocking IO.
277 * When it finishes, one packet has been decoded and can be found in
278 * ssl->s3->rrec.type - is the type of record
279 * ssl->s3->rrec.data, - data
280 * ssl->s3->rrec.length, - number of bytes
281 */
282 /* used only by ssl3_read_bytes */
ssl3_get_record(SSL * s)283 static int ssl3_get_record(SSL *s)
284 {
285 int ssl_major,ssl_minor,al;
286 int enc_err,n,i,ret= -1;
287 SSL3_RECORD *rr;
288 SSL_SESSION *sess;
289 unsigned char *p;
290 unsigned char md[EVP_MAX_MD_SIZE];
291 short version;
292 int mac_size;
293 int clear=0;
294 size_t extra;
295 int decryption_failed_or_bad_record_mac = 0;
296 unsigned char *mac = NULL;
297 #if defined(SSL3_ALIGN_PAYLOAD) && SSL3_ALIGN_PAYLOAD!=0
298 long align=SSL3_ALIGN_PAYLOAD;
299 #else
300 long align=0;
301 #endif
302
303 rr= &(s->s3->rrec);
304 sess=s->session;
305
306 if (s->options & SSL_OP_MICROSOFT_BIG_SSLV3_BUFFER)
307 extra=SSL3_RT_MAX_EXTRA;
308 else
309 extra=0;
310 if (!(SSL_get_mode(s) & SSL_MODE_SMALL_BUFFERS) &&
311 extra && !s->s3->init_extra)
312 {
313 /* An application error: SLS_OP_MICROSOFT_BIG_SSLV3_BUFFER
314 * set after ssl3_setup_buffers() was done */
315 SSLerr(SSL_F_SSL3_GET_RECORD, ERR_R_INTERNAL_ERROR);
316 return -1;
317 }
318
319 again:
320 /* check if we have the header */
321 if ( (s->rstate != SSL_ST_READ_BODY) ||
322 (s->packet_length < SSL3_RT_HEADER_LENGTH))
323 {
324 n=ssl3_read_n(s, SSL3_RT_HEADER_LENGTH, s->s3->rbuf.len, 0);
325 if (n <= 0) return(n); /* error or non-blocking */
326 s->rstate=SSL_ST_READ_BODY;
327
328 p=s->packet;
329
330 /* Pull apart the header into the SSL3_RECORD */
331 rr->type= *(p++);
332 ssl_major= *(p++);
333 ssl_minor= *(p++);
334 version=(ssl_major<<8)|ssl_minor;
335 n2s(p,rr->length);
336 #if 0
337 fprintf(stderr, "Record type=%d, Length=%d\n", rr->type, rr->length);
338 #endif
339
340 /* Lets check version */
341 if (!s->first_packet)
342 {
343 if (version != s->version)
344 {
345 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_WRONG_VERSION_NUMBER);
346 if ((s->version & 0xFF00) == (version & 0xFF00))
347 /* Send back error using their minor version number :-) */
348 s->version = (unsigned short)version;
349 al=SSL_AD_PROTOCOL_VERSION;
350 goto f_err;
351 }
352 }
353
354 if ((version>>8) != SSL3_VERSION_MAJOR)
355 {
356 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_WRONG_VERSION_NUMBER);
357 goto err;
358 }
359
360 /* If we receive a valid record larger than the current buffer size,
361 * allocate some memory for it.
362 */
363 if (rr->length > s->s3->rbuf.len - SSL3_RT_HEADER_LENGTH - align)
364 {
365 if ((p=OPENSSL_realloc(s->s3->rbuf.buf, rr->length + SSL3_RT_HEADER_LENGTH + align))==NULL)
366 {
367 SSLerr(SSL_F_SSL3_GET_RECORD,ERR_R_MALLOC_FAILURE);
368 goto err;
369 }
370 s->s3->rbuf.buf=p;
371 s->s3->rbuf.len=rr->length + SSL3_RT_HEADER_LENGTH + align;
372 s->packet= &(s->s3->rbuf.buf[0]);
373 }
374
375 if (rr->length > s->s3->rbuf.len - SSL3_RT_HEADER_LENGTH)
376 {
377 al=SSL_AD_RECORD_OVERFLOW;
378 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_PACKET_LENGTH_TOO_LONG);
379 goto f_err;
380 }
381
382 /* now s->rstate == SSL_ST_READ_BODY */
383 }
384
385 /* s->rstate == SSL_ST_READ_BODY, get and decode the data */
386
387 if (rr->length > s->packet_length-SSL3_RT_HEADER_LENGTH)
388 {
389 /* now s->packet_length == SSL3_RT_HEADER_LENGTH */
390 i=rr->length;
391 n=ssl3_read_n(s,i,i,1);
392 if (n <= 0) return(n); /* error or non-blocking io */
393 /* now n == rr->length,
394 * and s->packet_length == SSL3_RT_HEADER_LENGTH + rr->length */
395 }
396
397 s->rstate=SSL_ST_READ_HEADER; /* set state for later operations */
398
399 /* At this point, s->packet_length == SSL3_RT_HEADER_LNGTH + rr->length,
400 * and we have that many bytes in s->packet
401 */
402 rr->input= &(s->packet[SSL3_RT_HEADER_LENGTH]);
403
404 /* ok, we can now read from 's->packet' data into 'rr'
405 * rr->input points at rr->length bytes, which
406 * need to be copied into rr->data by either
407 * the decryption or by the decompression
408 * When the data is 'copied' into the rr->data buffer,
409 * rr->input will be pointed at the new buffer */
410
411 /* We now have - encrypted [ MAC [ compressed [ plain ] ] ]
412 * rr->length bytes of encrypted compressed stuff. */
413
414 /* check is not needed I believe */
415 if (rr->length > SSL3_RT_MAX_ENCRYPTED_LENGTH+extra)
416 {
417 al=SSL_AD_RECORD_OVERFLOW;
418 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_ENCRYPTED_LENGTH_TOO_LONG);
419 goto f_err;
420 }
421
422 /* decrypt in place in 'rr->input' */
423 rr->data=rr->input;
424
425 enc_err = s->method->ssl3_enc->enc(s,0);
426 if (enc_err <= 0)
427 {
428 if (enc_err == 0)
429 /* SSLerr() and ssl3_send_alert() have been called */
430 goto err;
431
432 /* Otherwise enc_err == -1, which indicates bad padding
433 * (rec->length has not been changed in this case).
434 * To minimize information leaked via timing, we will perform
435 * the MAC computation anyway. */
436 decryption_failed_or_bad_record_mac = 1;
437 }
438
439 #ifdef TLS_DEBUG
440 printf("dec %d\n",rr->length);
441 { unsigned int z; for (z=0; z<rr->length; z++) printf("%02X%c",rr->data[z],((z+1)%16)?' ':'\n'); }
442 printf("\n");
443 #endif
444
445 /* r->length is now the compressed data plus mac */
446 if ( (sess == NULL) ||
447 (s->enc_read_ctx == NULL) ||
448 (EVP_MD_CTX_md(s->read_hash) == NULL))
449 clear=1;
450
451 if (!clear)
452 {
453 /* !clear => s->read_hash != NULL => mac_size != -1 */
454 mac_size=EVP_MD_CTX_size(s->read_hash);
455 OPENSSL_assert(mac_size >= 0);
456
457 if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH+extra+mac_size)
458 {
459 #if 0 /* OK only for stream ciphers (then rr->length is visible from ciphertext anyway) */
460 al=SSL_AD_RECORD_OVERFLOW;
461 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_PRE_MAC_LENGTH_TOO_LONG);
462 goto f_err;
463 #else
464 decryption_failed_or_bad_record_mac = 1;
465 #endif
466 }
467 /* check the MAC for rr->input (it's in mac_size bytes at the tail) */
468 if (rr->length >= (unsigned int)mac_size)
469 {
470 rr->length -= mac_size;
471 mac = &rr->data[rr->length];
472 }
473 else
474 {
475 /* record (minus padding) is too short to contain a MAC */
476 #if 0 /* OK only for stream ciphers */
477 al=SSL_AD_DECODE_ERROR;
478 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_LENGTH_TOO_SHORT);
479 goto f_err;
480 #else
481 decryption_failed_or_bad_record_mac = 1;
482 rr->length = 0;
483 #endif
484 }
485 i=s->method->ssl3_enc->mac(s,md,0);
486 if (i < 0 || mac == NULL || memcmp(md, mac, (size_t)mac_size) != 0)
487 {
488 decryption_failed_or_bad_record_mac = 1;
489 }
490 }
491
492 if (decryption_failed_or_bad_record_mac)
493 {
494 /* A separate 'decryption_failed' alert was introduced with TLS 1.0,
495 * SSL 3.0 only has 'bad_record_mac'. But unless a decryption
496 * failure is directly visible from the ciphertext anyway,
497 * we should not reveal which kind of error occured -- this
498 * might become visible to an attacker (e.g. via a logfile) */
499 al=SSL_AD_BAD_RECORD_MAC;
500 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_DECRYPTION_FAILED_OR_BAD_RECORD_MAC);
501 goto f_err;
502 }
503
504 /* r->length is now just compressed */
505 if (s->expand != NULL)
506 {
507 if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH+extra)
508 {
509 al=SSL_AD_RECORD_OVERFLOW;
510 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_COMPRESSED_LENGTH_TOO_LONG);
511 goto f_err;
512 }
513 if (!ssl3_do_uncompress(s))
514 {
515 al=SSL_AD_DECOMPRESSION_FAILURE;
516 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_BAD_DECOMPRESSION);
517 goto f_err;
518 }
519 }
520
521 if (rr->length > SSL3_RT_MAX_PLAIN_LENGTH+extra)
522 {
523 al=SSL_AD_RECORD_OVERFLOW;
524 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_DATA_LENGTH_TOO_LONG);
525 goto f_err;
526 }
527
528 rr->off=0;
529 /* So at this point the following is true
530 * ssl->s3->rrec.type is the type of record
531 * ssl->s3->rrec.length == number of bytes in record
532 * ssl->s3->rrec.off == offset to first valid byte
533 * ssl->s3->rrec.data == where to take bytes from, increment
534 * after use :-).
535 */
536
537 /* we have pulled in a full packet so zero things */
538 s->packet_length=0;
539
540 /* just read a 0 length packet */
541 if (rr->length == 0) goto again;
542
543 #if 0
544 fprintf(stderr, "Ultimate Record type=%d, Length=%d\n", rr->type, rr->length);
545 #endif
546
547 return(1);
548
549 f_err:
550 ssl3_send_alert(s,SSL3_AL_FATAL,al);
551 err:
552 return(ret);
553 }
554
ssl3_do_uncompress(SSL * ssl)555 int ssl3_do_uncompress(SSL *ssl)
556 {
557 #ifndef OPENSSL_NO_COMP
558 int i;
559 SSL3_RECORD *rr;
560
561 rr= &(ssl->s3->rrec);
562 i=COMP_expand_block(ssl->expand,rr->comp,
563 SSL3_RT_MAX_PLAIN_LENGTH,rr->data,(int)rr->length);
564 if (i < 0)
565 return(0);
566 else
567 rr->length=i;
568 rr->data=rr->comp;
569 #endif
570 return(1);
571 }
572
ssl3_do_compress(SSL * ssl)573 int ssl3_do_compress(SSL *ssl)
574 {
575 #ifndef OPENSSL_NO_COMP
576 int i;
577 SSL3_RECORD *wr;
578
579 wr= &(ssl->s3->wrec);
580 i=COMP_compress_block(ssl->compress,wr->data,
581 SSL3_RT_MAX_COMPRESSED_LENGTH,
582 wr->input,(int)wr->length);
583 if (i < 0)
584 return(0);
585 else
586 wr->length=i;
587
588 wr->input=wr->data;
589 #endif
590 return(1);
591 }
592
593 /* Call this to write data in records of type 'type'
594 * It will return <= 0 if not all data has been sent or non-blocking IO.
595 */
ssl3_write_bytes(SSL * s,int type,const void * buf_,int len)596 int ssl3_write_bytes(SSL *s, int type, const void *buf_, int len)
597 {
598 const unsigned char *buf=buf_;
599 unsigned int tot,n,nw;
600 int i;
601 unsigned int max_plain_length;
602
603 s->rwstate=SSL_NOTHING;
604 tot=s->s3->wnum;
605 s->s3->wnum=0;
606
607 if (SSL_in_init(s) && !s->in_handshake)
608 {
609 i=s->handshake_func(s);
610 if (i < 0) return(i);
611 if (i == 0)
612 {
613 SSLerr(SSL_F_SSL3_WRITE_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
614 return -1;
615 }
616 }
617
618 n=(len-tot);
619 for (;;)
620 {
621 if (type == SSL3_RT_APPLICATION_DATA && (SSL_get_mode(s) & SSL_MODE_SMALL_BUFFERS))
622 max_plain_length = SSL3_RT_DEFAULT_PLAIN_LENGTH;
623 else
624 max_plain_length = s->max_send_fragment;
625
626 if (n > max_plain_length)
627 nw = max_plain_length;
628 else
629 nw=n;
630
631 i=do_ssl3_write(s, type, &(buf[tot]), nw, 0);
632 if (i <= 0)
633 {
634 s->s3->wnum=tot;
635 return i;
636 }
637
638 if ((i == (int)n) ||
639 (type == SSL3_RT_APPLICATION_DATA &&
640 (s->mode & SSL_MODE_ENABLE_PARTIAL_WRITE)))
641 {
642 /* next chunk of data should get another prepended empty fragment
643 * in ciphersuites with known-IV weakness: */
644 s->s3->empty_fragment_done = 0;
645
646 return tot+i;
647 }
648
649 n-=i;
650 tot+=i;
651 }
652 }
653
do_ssl3_write(SSL * s,int type,const unsigned char * buf,unsigned int len,int create_empty_fragment)654 static int do_ssl3_write(SSL *s, int type, const unsigned char *buf,
655 unsigned int len, int create_empty_fragment)
656 {
657 unsigned char *p,*plen;
658 int i,mac_size,clear=0;
659 int prefix_len=0;
660 long align=0;
661 SSL3_RECORD *wr;
662 SSL3_BUFFER *wb=&(s->s3->wbuf);
663 SSL_SESSION *sess;
664
665 if (wb->buf == NULL)
666 if (!ssl3_setup_write_buffer(s))
667 return -1;
668
669 /* first check if there is a SSL3_BUFFER still being written
670 * out. This will happen with non blocking IO */
671 if (wb->left != 0)
672 return(ssl3_write_pending(s,type,buf,len));
673
674 /* If we have an alert to send, lets send it */
675 if (s->s3->alert_dispatch)
676 {
677 i=s->method->ssl_dispatch_alert(s);
678 if (i <= 0)
679 return(i);
680 /* if it went, fall through and send more stuff */
681 }
682
683 if (len == 0 && !create_empty_fragment)
684 return 0;
685
686 wr= &(s->s3->wrec);
687 sess=s->session;
688
689 if ( (sess == NULL) ||
690 (s->enc_write_ctx == NULL) ||
691 (EVP_MD_CTX_md(s->write_hash) == NULL))
692 clear=1;
693
694 if (clear)
695 mac_size=0;
696 else
697 {
698 mac_size=EVP_MD_CTX_size(s->write_hash);
699 if (mac_size < 0)
700 goto err;
701 }
702
703 /* 'create_empty_fragment' is true only when this function calls itself */
704 if (!clear && !create_empty_fragment && !s->s3->empty_fragment_done)
705 {
706 /* countermeasure against known-IV weakness in CBC ciphersuites
707 * (see http://www.openssl.org/~bodo/tls-cbc.txt) */
708
709 if (s->s3->need_empty_fragments && type == SSL3_RT_APPLICATION_DATA)
710 {
711 /* recursive function call with 'create_empty_fragment' set;
712 * this prepares and buffers the data for an empty fragment
713 * (these 'prefix_len' bytes are sent out later
714 * together with the actual payload) */
715 prefix_len = do_ssl3_write(s, type, buf, 0, 1);
716 if (prefix_len <= 0)
717 goto err;
718
719 if (prefix_len >
720 (SSL3_RT_HEADER_LENGTH + SSL3_RT_SEND_MAX_ENCRYPTED_OVERHEAD))
721 {
722 /* insufficient space */
723 SSLerr(SSL_F_DO_SSL3_WRITE, ERR_R_INTERNAL_ERROR);
724 goto err;
725 }
726 }
727
728 s->s3->empty_fragment_done = 1;
729 }
730
731 /* resize if necessary to hold the data. */
732 if (len + SSL3_RT_DEFAULT_WRITE_OVERHEAD > wb->len)
733 {
734 if ((p=OPENSSL_realloc(wb->buf, len + SSL3_RT_DEFAULT_WRITE_OVERHEAD))==NULL)
735 {
736 SSLerr(SSL_F_DO_SSL3_WRITE,ERR_R_MALLOC_FAILURE);
737 goto err;
738 }
739 wb->buf = p;
740 wb->len = len + SSL3_RT_DEFAULT_WRITE_OVERHEAD;
741 }
742
743 if (create_empty_fragment)
744 {
745 #if defined(SSL3_ALIGN_PAYLOAD) && SSL3_ALIGN_PAYLOAD!=0
746 /* extra fragment would be couple of cipher blocks,
747 * which would be multiple of SSL3_ALIGN_PAYLOAD, so
748 * if we want to align the real payload, then we can
749 * just pretent we simply have two headers. */
750 align = (long)wb->buf + 2*SSL3_RT_HEADER_LENGTH;
751 align = (-align)&(SSL3_ALIGN_PAYLOAD-1);
752 #endif
753 p = wb->buf + align;
754 wb->offset = align;
755 }
756 else if (prefix_len)
757 {
758 p = wb->buf + wb->offset + prefix_len;
759 }
760 else
761 {
762 #if defined(SSL3_ALIGN_PAYLOAD) && SSL3_ALIGN_PAYLOAD!=0
763 align = (long)wb->buf + SSL3_RT_HEADER_LENGTH;
764 align = (-align)&(SSL3_ALIGN_PAYLOAD-1);
765 #endif
766 p = wb->buf + align;
767 wb->offset = align;
768 }
769
770 /* write the header */
771
772 *(p++)=type&0xff;
773 wr->type=type;
774
775 *(p++)=(s->version>>8);
776 *(p++)=s->version&0xff;
777
778 /* field where we are to write out packet length */
779 plen=p;
780 p+=2;
781
782 /* lets setup the record stuff. */
783 wr->data=p;
784 wr->length=(int)len;
785 wr->input=(unsigned char *)buf;
786
787 /* we now 'read' from wr->input, wr->length bytes into
788 * wr->data */
789
790 /* first we compress */
791 if (s->compress != NULL)
792 {
793 if (!ssl3_do_compress(s))
794 {
795 SSLerr(SSL_F_DO_SSL3_WRITE,SSL_R_COMPRESSION_FAILURE);
796 goto err;
797 }
798 }
799 else
800 {
801 memcpy(wr->data,wr->input,wr->length);
802 wr->input=wr->data;
803 }
804
805 /* we should still have the output to wr->data and the input
806 * from wr->input. Length should be wr->length.
807 * wr->data still points in the wb->buf */
808
809 if (mac_size != 0)
810 {
811 if (s->method->ssl3_enc->mac(s,&(p[wr->length]),1) < 0)
812 goto err;
813 wr->length+=mac_size;
814 wr->input=p;
815 wr->data=p;
816 }
817
818 /* ssl3_enc can only have an error on read */
819 s->method->ssl3_enc->enc(s,1);
820
821 /* record length after mac and block padding */
822 s2n(wr->length,plen);
823
824 /* we should now have
825 * wr->data pointing to the encrypted data, which is
826 * wr->length long */
827 wr->type=type; /* not needed but helps for debugging */
828 wr->length+=SSL3_RT_HEADER_LENGTH;
829
830 if (create_empty_fragment)
831 {
832 /* we are in a recursive call;
833 * just return the length, don't write out anything here
834 */
835 return wr->length;
836 }
837
838 /* now let's set up wb */
839 wb->left = prefix_len + wr->length;
840
841 /* memorize arguments so that ssl3_write_pending can detect bad write retries later */
842 s->s3->wpend_tot=len;
843 s->s3->wpend_buf=buf;
844 s->s3->wpend_type=type;
845 s->s3->wpend_ret=len;
846
847 /* we now just need to write the buffer */
848 return ssl3_write_pending(s,type,buf,len);
849 err:
850 return -1;
851 }
852
853 /* 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)854 int ssl3_write_pending(SSL *s, int type, const unsigned char *buf,
855 unsigned int len)
856 {
857 int i;
858 SSL3_BUFFER *wb=&(s->s3->wbuf);
859
860 /* XXXX */
861 if ((s->s3->wpend_tot > (int)len)
862 || ((s->s3->wpend_buf != buf) &&
863 !(s->mode & SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER))
864 || (s->s3->wpend_type != type))
865 {
866 SSLerr(SSL_F_SSL3_WRITE_PENDING,SSL_R_BAD_WRITE_RETRY);
867 return(-1);
868 }
869
870 for (;;)
871 {
872 clear_sys_error();
873 if (s->wbio != NULL)
874 {
875 s->rwstate=SSL_WRITING;
876 i=BIO_write(s->wbio,
877 (char *)&(wb->buf[wb->offset]),
878 (unsigned int)wb->left);
879 }
880 else
881 {
882 SSLerr(SSL_F_SSL3_WRITE_PENDING,SSL_R_BIO_NOT_SET);
883 i= -1;
884 }
885 if (i == wb->left)
886 {
887 wb->left=0;
888 wb->offset+=i;
889 if (s->mode & SSL_MODE_RELEASE_BUFFERS &&
890 SSL_version(s) != DTLS1_VERSION && SSL_version(s) != DTLS1_BAD_VER)
891 ssl3_release_write_buffer(s);
892 s->rwstate=SSL_NOTHING;
893 return(s->s3->wpend_ret);
894 }
895 else if (i <= 0) {
896 if (s->version == DTLS1_VERSION ||
897 s->version == DTLS1_BAD_VER) {
898 /* For DTLS, just drop it. That's kind of the whole
899 point in using a datagram service */
900 wb->left = 0;
901 }
902 return(i);
903 }
904 wb->offset+=i;
905 wb->left-=i;
906 }
907 }
908
909 /* Return up to 'len' payload bytes received in 'type' records.
910 * 'type' is one of the following:
911 *
912 * - SSL3_RT_HANDSHAKE (when ssl3_get_message calls us)
913 * - SSL3_RT_APPLICATION_DATA (when ssl3_read calls us)
914 * - 0 (during a shutdown, no data has to be returned)
915 *
916 * If we don't have stored data to work from, read a SSL/TLS record first
917 * (possibly multiple records if we still don't have anything to return).
918 *
919 * This function must handle any surprises the peer may have for us, such as
920 * Alert records (e.g. close_notify), ChangeCipherSpec records (not really
921 * a surprise, but handled as if it were), or renegotiation requests.
922 * Also if record payloads contain fragments too small to process, we store
923 * them until there is enough for the respective protocol (the record protocol
924 * may use arbitrary fragmentation and even interleaving):
925 * Change cipher spec protocol
926 * just 1 byte needed, no need for keeping anything stored
927 * Alert protocol
928 * 2 bytes needed (AlertLevel, AlertDescription)
929 * Handshake protocol
930 * 4 bytes needed (HandshakeType, uint24 length) -- we just have
931 * to detect unexpected Client Hello and Hello Request messages
932 * here, anything else is handled by higher layers
933 * Application data protocol
934 * none of our business
935 */
ssl3_read_bytes(SSL * s,int type,unsigned char * buf,int len,int peek)936 int ssl3_read_bytes(SSL *s, int type, unsigned char *buf, int len, int peek)
937 {
938 int al,i,j,ret;
939 unsigned int n;
940 SSL3_RECORD *rr;
941 void (*cb)(const SSL *ssl,int type2,int val)=NULL;
942
943 if (s->s3->rbuf.buf == NULL) /* Not initialized yet */
944 if (!ssl3_setup_read_buffer(s))
945 return(-1);
946
947 if ((type && (type != SSL3_RT_APPLICATION_DATA) && (type != SSL3_RT_HANDSHAKE) && type) ||
948 (peek && (type != SSL3_RT_APPLICATION_DATA)))
949 {
950 SSLerr(SSL_F_SSL3_READ_BYTES, ERR_R_INTERNAL_ERROR);
951 return -1;
952 }
953
954 if ((type == SSL3_RT_HANDSHAKE) && (s->s3->handshake_fragment_len > 0))
955 /* (partially) satisfy request from storage */
956 {
957 unsigned char *src = s->s3->handshake_fragment;
958 unsigned char *dst = buf;
959 unsigned int k;
960
961 /* peek == 0 */
962 n = 0;
963 while ((len > 0) && (s->s3->handshake_fragment_len > 0))
964 {
965 *dst++ = *src++;
966 len--; s->s3->handshake_fragment_len--;
967 n++;
968 }
969 /* move any remaining fragment bytes: */
970 for (k = 0; k < s->s3->handshake_fragment_len; k++)
971 s->s3->handshake_fragment[k] = *src++;
972 return n;
973 }
974
975 /* Now s->s3->handshake_fragment_len == 0 if type == SSL3_RT_HANDSHAKE. */
976
977 if (!s->in_handshake && SSL_in_init(s))
978 {
979 /* type == SSL3_RT_APPLICATION_DATA */
980 i=s->handshake_func(s);
981 if (i < 0) return(i);
982 if (i == 0)
983 {
984 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
985 return(-1);
986 }
987 }
988 start:
989 s->rwstate=SSL_NOTHING;
990
991 /* s->s3->rrec.type - is the type of record
992 * s->s3->rrec.data, - data
993 * s->s3->rrec.off, - offset into 'data' for next read
994 * s->s3->rrec.length, - number of bytes. */
995 rr = &(s->s3->rrec);
996
997 /* get new packet if necessary */
998 if ((rr->length == 0) || (s->rstate == SSL_ST_READ_BODY))
999 {
1000 ret=ssl3_get_record(s);
1001 if (ret <= 0) return(ret);
1002 }
1003
1004 /* we now have a packet which can be read and processed */
1005
1006 if (s->s3->change_cipher_spec /* set when we receive ChangeCipherSpec,
1007 * reset by ssl3_get_finished */
1008 && (rr->type != SSL3_RT_HANDSHAKE))
1009 {
1010 al=SSL_AD_UNEXPECTED_MESSAGE;
1011 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_DATA_BETWEEN_CCS_AND_FINISHED);
1012 goto f_err;
1013 }
1014
1015 /* If the other end has shut down, throw anything we read away
1016 * (even in 'peek' mode) */
1017 if (s->shutdown & SSL_RECEIVED_SHUTDOWN)
1018 {
1019 rr->length=0;
1020 s->rwstate=SSL_NOTHING;
1021 return(0);
1022 }
1023
1024
1025 if (type == rr->type) /* SSL3_RT_APPLICATION_DATA or SSL3_RT_HANDSHAKE */
1026 {
1027 /* make sure that we are not getting application data when we
1028 * are doing a handshake for the first time */
1029 if (SSL_in_init(s) && (type == SSL3_RT_APPLICATION_DATA) &&
1030 (s->enc_read_ctx == NULL))
1031 {
1032 al=SSL_AD_UNEXPECTED_MESSAGE;
1033 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_APP_DATA_IN_HANDSHAKE);
1034 goto f_err;
1035 }
1036
1037 if (len <= 0) return(len);
1038
1039 if ((unsigned int)len > rr->length)
1040 n = rr->length;
1041 else
1042 n = (unsigned int)len;
1043
1044 memcpy(buf,&(rr->data[rr->off]),n);
1045 if (!peek)
1046 {
1047 rr->length-=n;
1048 rr->off+=n;
1049 if (rr->length == 0)
1050 {
1051 s->rstate=SSL_ST_READ_HEADER;
1052 rr->off=0;
1053 if (s->mode & SSL_MODE_RELEASE_BUFFERS)
1054 ssl3_release_read_buffer(s);
1055 }
1056 }
1057 return(n);
1058 }
1059
1060
1061 /* If we get here, then type != rr->type; if we have a handshake
1062 * message, then it was unexpected (Hello Request or Client Hello). */
1063
1064 /* In case of record types for which we have 'fragment' storage,
1065 * fill that so that we can process the data at a fixed place.
1066 */
1067 {
1068 unsigned int dest_maxlen = 0;
1069 unsigned char *dest = NULL;
1070 unsigned int *dest_len = NULL;
1071
1072 if (rr->type == SSL3_RT_HANDSHAKE)
1073 {
1074 dest_maxlen = sizeof s->s3->handshake_fragment;
1075 dest = s->s3->handshake_fragment;
1076 dest_len = &s->s3->handshake_fragment_len;
1077 }
1078 else if (rr->type == SSL3_RT_ALERT)
1079 {
1080 dest_maxlen = sizeof s->s3->alert_fragment;
1081 dest = s->s3->alert_fragment;
1082 dest_len = &s->s3->alert_fragment_len;
1083 }
1084
1085 if (dest_maxlen > 0)
1086 {
1087 n = dest_maxlen - *dest_len; /* available space in 'dest' */
1088 if (rr->length < n)
1089 n = rr->length; /* available bytes */
1090
1091 /* now move 'n' bytes: */
1092 while (n-- > 0)
1093 {
1094 dest[(*dest_len)++] = rr->data[rr->off++];
1095 rr->length--;
1096 }
1097
1098 if (*dest_len < dest_maxlen)
1099 goto start; /* fragment was too small */
1100 }
1101 }
1102
1103 /* s->s3->handshake_fragment_len == 4 iff rr->type == SSL3_RT_HANDSHAKE;
1104 * s->s3->alert_fragment_len == 2 iff rr->type == SSL3_RT_ALERT.
1105 * (Possibly rr is 'empty' now, i.e. rr->length may be 0.) */
1106
1107 /* If we are a client, check for an incoming 'Hello Request': */
1108 if ((!s->server) &&
1109 (s->s3->handshake_fragment_len >= 4) &&
1110 (s->s3->handshake_fragment[0] == SSL3_MT_HELLO_REQUEST) &&
1111 (s->session != NULL) && (s->session->cipher != NULL))
1112 {
1113 s->s3->handshake_fragment_len = 0;
1114
1115 if ((s->s3->handshake_fragment[1] != 0) ||
1116 (s->s3->handshake_fragment[2] != 0) ||
1117 (s->s3->handshake_fragment[3] != 0))
1118 {
1119 al=SSL_AD_DECODE_ERROR;
1120 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_BAD_HELLO_REQUEST);
1121 goto f_err;
1122 }
1123
1124 if (s->msg_callback)
1125 s->msg_callback(0, s->version, SSL3_RT_HANDSHAKE, s->s3->handshake_fragment, 4, s, s->msg_callback_arg);
1126
1127 if (SSL_is_init_finished(s) &&
1128 !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS) &&
1129 !s->s3->renegotiate)
1130 {
1131 ssl3_renegotiate(s);
1132 if (ssl3_renegotiate_check(s))
1133 {
1134 i=s->handshake_func(s);
1135 if (i < 0) return(i);
1136 if (i == 0)
1137 {
1138 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
1139 return(-1);
1140 }
1141
1142 if (!(s->mode & SSL_MODE_AUTO_RETRY))
1143 {
1144 if (s->s3->rbuf.left == 0) /* no read-ahead left? */
1145 {
1146 BIO *bio;
1147 /* In the case where we try to read application data,
1148 * but we trigger an SSL handshake, we return -1 with
1149 * the retry option set. Otherwise renegotiation may
1150 * cause nasty problems in the blocking world */
1151 s->rwstate=SSL_READING;
1152 bio=SSL_get_rbio(s);
1153 BIO_clear_retry_flags(bio);
1154 BIO_set_retry_read(bio);
1155 return(-1);
1156 }
1157 }
1158 }
1159 }
1160 /* we either finished a handshake or ignored the request,
1161 * now try again to obtain the (application) data we were asked for */
1162 goto start;
1163 }
1164 /* If we are a server and get a client hello when renegotiation isn't
1165 * allowed send back a no renegotiation alert and carry on.
1166 * WARNING: experimental code, needs reviewing (steve)
1167 */
1168 if (s->server &&
1169 SSL_is_init_finished(s) &&
1170 !s->s3->send_connection_binding &&
1171 (s->version > SSL3_VERSION) &&
1172 (s->s3->handshake_fragment_len >= 4) &&
1173 (s->s3->handshake_fragment[0] == SSL3_MT_CLIENT_HELLO) &&
1174 (s->session != NULL) && (s->session->cipher != NULL) &&
1175 !(s->ctx->options & SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION))
1176
1177 {
1178 /*s->s3->handshake_fragment_len = 0;*/
1179 rr->length = 0;
1180 ssl3_send_alert(s,SSL3_AL_WARNING, SSL_AD_NO_RENEGOTIATION);
1181 goto start;
1182 }
1183 if (s->s3->alert_fragment_len >= 2)
1184 {
1185 int alert_level = s->s3->alert_fragment[0];
1186 int alert_descr = s->s3->alert_fragment[1];
1187
1188 s->s3->alert_fragment_len = 0;
1189
1190 if (s->msg_callback)
1191 s->msg_callback(0, s->version, SSL3_RT_ALERT, s->s3->alert_fragment, 2, s, s->msg_callback_arg);
1192
1193 if (s->info_callback != NULL)
1194 cb=s->info_callback;
1195 else if (s->ctx->info_callback != NULL)
1196 cb=s->ctx->info_callback;
1197
1198 if (cb != NULL)
1199 {
1200 j = (alert_level << 8) | alert_descr;
1201 cb(s, SSL_CB_READ_ALERT, j);
1202 }
1203
1204 if (alert_level == 1) /* warning */
1205 {
1206 s->s3->warn_alert = alert_descr;
1207 if (alert_descr == SSL_AD_CLOSE_NOTIFY)
1208 {
1209 s->shutdown |= SSL_RECEIVED_SHUTDOWN;
1210 return(0);
1211 }
1212 /* This is a warning but we receive it if we requested
1213 * renegotiation and the peer denied it. Terminate with
1214 * a fatal alert because if application tried to
1215 * renegotiatie it presumably had a good reason and
1216 * expects it to succeed.
1217 *
1218 * In future we might have a renegotiation where we
1219 * don't care if the peer refused it where we carry on.
1220 */
1221 else if (alert_descr == SSL_AD_NO_RENEGOTIATION)
1222 {
1223 al = SSL_AD_HANDSHAKE_FAILURE;
1224 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_NO_RENEGOTIATION);
1225 goto f_err;
1226 }
1227 }
1228 else if (alert_level == 2) /* fatal */
1229 {
1230 char tmp[16];
1231
1232 s->rwstate=SSL_NOTHING;
1233 s->s3->fatal_alert = alert_descr;
1234 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_AD_REASON_OFFSET + alert_descr);
1235 BIO_snprintf(tmp,sizeof tmp,"%d",alert_descr);
1236 ERR_add_error_data(2,"SSL alert number ",tmp);
1237 s->shutdown|=SSL_RECEIVED_SHUTDOWN;
1238 SSL_CTX_remove_session(s->ctx,s->session);
1239 return(0);
1240 }
1241 else
1242 {
1243 al=SSL_AD_ILLEGAL_PARAMETER;
1244 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNKNOWN_ALERT_TYPE);
1245 goto f_err;
1246 }
1247
1248 goto start;
1249 }
1250
1251 if (s->shutdown & SSL_SENT_SHUTDOWN) /* but we have not received a shutdown */
1252 {
1253 s->rwstate=SSL_NOTHING;
1254 rr->length=0;
1255 return(0);
1256 }
1257
1258 if (rr->type == SSL3_RT_CHANGE_CIPHER_SPEC)
1259 {
1260 /* 'Change Cipher Spec' is just a single byte, so we know
1261 * exactly what the record payload has to look like */
1262 if ( (rr->length != 1) || (rr->off != 0) ||
1263 (rr->data[0] != SSL3_MT_CCS))
1264 {
1265 al=SSL_AD_ILLEGAL_PARAMETER;
1266 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_BAD_CHANGE_CIPHER_SPEC);
1267 goto f_err;
1268 }
1269
1270 /* Check we have a cipher to change to */
1271 if (s->s3->tmp.new_cipher == NULL)
1272 {
1273 al=SSL_AD_UNEXPECTED_MESSAGE;
1274 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_CCS_RECEIVED_EARLY);
1275 goto f_err;
1276 }
1277
1278 rr->length=0;
1279
1280 if (s->msg_callback)
1281 s->msg_callback(0, s->version, SSL3_RT_CHANGE_CIPHER_SPEC, rr->data, 1, s, s->msg_callback_arg);
1282
1283 s->s3->change_cipher_spec=1;
1284 if (!ssl3_do_change_cipher_spec(s))
1285 goto err;
1286 else
1287 goto start;
1288 }
1289
1290 /* Unexpected handshake message (Client Hello, or protocol violation) */
1291 if ((s->s3->handshake_fragment_len >= 4) && !s->in_handshake)
1292 {
1293 if (((s->state&SSL_ST_MASK) == SSL_ST_OK) &&
1294 !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS))
1295 {
1296 #if 0 /* worked only because C operator preferences are not as expected (and
1297 * because this is not really needed for clients except for detecting
1298 * protocol violations): */
1299 s->state=SSL_ST_BEFORE|(s->server)
1300 ?SSL_ST_ACCEPT
1301 :SSL_ST_CONNECT;
1302 #else
1303 s->state = s->server ? SSL_ST_ACCEPT : SSL_ST_CONNECT;
1304 #endif
1305 s->new_session=1;
1306 }
1307 i=s->handshake_func(s);
1308 if (i < 0) return(i);
1309 if (i == 0)
1310 {
1311 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
1312 return(-1);
1313 }
1314
1315 if (!(s->mode & SSL_MODE_AUTO_RETRY))
1316 {
1317 if (s->s3->rbuf.left == 0) /* no read-ahead left? */
1318 {
1319 BIO *bio;
1320 /* In the case where we try to read application data,
1321 * but we trigger an SSL handshake, we return -1 with
1322 * the retry option set. Otherwise renegotiation may
1323 * cause nasty problems in the blocking world */
1324 s->rwstate=SSL_READING;
1325 bio=SSL_get_rbio(s);
1326 BIO_clear_retry_flags(bio);
1327 BIO_set_retry_read(bio);
1328 return(-1);
1329 }
1330 }
1331 goto start;
1332 }
1333
1334 switch (rr->type)
1335 {
1336 default:
1337 #ifndef OPENSSL_NO_TLS
1338 /* TLS just ignores unknown message types */
1339 if (s->version == TLS1_VERSION)
1340 {
1341 rr->length = 0;
1342 goto start;
1343 }
1344 #endif
1345 al=SSL_AD_UNEXPECTED_MESSAGE;
1346 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNEXPECTED_RECORD);
1347 goto f_err;
1348 case SSL3_RT_CHANGE_CIPHER_SPEC:
1349 case SSL3_RT_ALERT:
1350 case SSL3_RT_HANDSHAKE:
1351 /* we already handled all of these, with the possible exception
1352 * of SSL3_RT_HANDSHAKE when s->in_handshake is set, but that
1353 * should not happen when type != rr->type */
1354 al=SSL_AD_UNEXPECTED_MESSAGE;
1355 SSLerr(SSL_F_SSL3_READ_BYTES,ERR_R_INTERNAL_ERROR);
1356 goto f_err;
1357 case SSL3_RT_APPLICATION_DATA:
1358 /* At this point, we were expecting handshake data,
1359 * but have application data. If the library was
1360 * running inside ssl3_read() (i.e. in_read_app_data
1361 * is set) and it makes sense to read application data
1362 * at this point (session renegotiation not yet started),
1363 * we will indulge it.
1364 */
1365 if (s->s3->in_read_app_data &&
1366 (s->s3->total_renegotiations != 0) &&
1367 ((
1368 (s->state & SSL_ST_CONNECT) &&
1369 (s->state >= SSL3_ST_CW_CLNT_HELLO_A) &&
1370 (s->state <= SSL3_ST_CR_SRVR_HELLO_A)
1371 ) || (
1372 (s->state & SSL_ST_ACCEPT) &&
1373 (s->state <= SSL3_ST_SW_HELLO_REQ_A) &&
1374 (s->state >= SSL3_ST_SR_CLNT_HELLO_A)
1375 )
1376 ))
1377 {
1378 s->s3->in_read_app_data=2;
1379 return(-1);
1380 }
1381 else
1382 {
1383 al=SSL_AD_UNEXPECTED_MESSAGE;
1384 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNEXPECTED_RECORD);
1385 goto f_err;
1386 }
1387 }
1388 /* not reached */
1389
1390 f_err:
1391 ssl3_send_alert(s,SSL3_AL_FATAL,al);
1392 err:
1393 return(-1);
1394 }
1395
ssl3_do_change_cipher_spec(SSL * s)1396 int ssl3_do_change_cipher_spec(SSL *s)
1397 {
1398 int i;
1399 #ifdef OPENSSL_NO_NEXTPROTONEG
1400 const char *sender;
1401 int slen;
1402 #endif
1403
1404 if (s->state & SSL_ST_ACCEPT)
1405 i=SSL3_CHANGE_CIPHER_SERVER_READ;
1406 else
1407 i=SSL3_CHANGE_CIPHER_CLIENT_READ;
1408
1409 if (s->s3->tmp.key_block == NULL)
1410 {
1411 if (s->session == NULL)
1412 {
1413 /* might happen if dtls1_read_bytes() calls this */
1414 SSLerr(SSL_F_SSL3_DO_CHANGE_CIPHER_SPEC,SSL_R_CCS_RECEIVED_EARLY);
1415 return (0);
1416 }
1417
1418 s->session->cipher=s->s3->tmp.new_cipher;
1419 if (!s->method->ssl3_enc->setup_key_block(s)) return(0);
1420 }
1421
1422 if (!s->method->ssl3_enc->change_cipher_state(s,i))
1423 return(0);
1424
1425 #ifdef OPENSSL_NO_NEXTPROTONEG
1426 /* we have to record the message digest at
1427 * this point so we can get it before we read
1428 * the finished message */
1429 if (s->state & SSL_ST_CONNECT)
1430 {
1431 sender=s->method->ssl3_enc->server_finished_label;
1432 slen=s->method->ssl3_enc->server_finished_label_len;
1433 }
1434 else
1435 {
1436 sender=s->method->ssl3_enc->client_finished_label;
1437 slen=s->method->ssl3_enc->client_finished_label_len;
1438 }
1439
1440 s->s3->tmp.peer_finish_md_len = s->method->ssl3_enc->final_finish_mac(s,
1441 sender,slen,s->s3->tmp.peer_finish_md);
1442 #endif
1443
1444 return(1);
1445 }
1446
ssl3_send_alert(SSL * s,int level,int desc)1447 int ssl3_send_alert(SSL *s, int level, int desc)
1448 {
1449 /* Map tls/ssl alert value to correct one */
1450 desc=s->method->ssl3_enc->alert_value(desc);
1451 if (s->version == SSL3_VERSION && desc == SSL_AD_PROTOCOL_VERSION)
1452 desc = SSL_AD_HANDSHAKE_FAILURE; /* SSL 3.0 does not have protocol_version alerts */
1453 if (desc < 0) return -1;
1454 /* If a fatal one, remove from cache */
1455 if ((level == 2) && (s->session != NULL))
1456 SSL_CTX_remove_session(s->ctx,s->session);
1457
1458 s->s3->alert_dispatch=1;
1459 s->s3->send_alert[0]=level;
1460 s->s3->send_alert[1]=desc;
1461 if (s->s3->wbuf.left == 0) /* data still being written out? */
1462 return s->method->ssl_dispatch_alert(s);
1463 /* else data is still being written out, we will get written
1464 * some time in the future */
1465 return -1;
1466 }
1467
ssl3_dispatch_alert(SSL * s)1468 int ssl3_dispatch_alert(SSL *s)
1469 {
1470 int i,j;
1471 void (*cb)(const SSL *ssl,int type,int val)=NULL;
1472
1473 s->s3->alert_dispatch=0;
1474 i = do_ssl3_write(s, SSL3_RT_ALERT, &s->s3->send_alert[0], 2, 0);
1475 if (i <= 0)
1476 {
1477 s->s3->alert_dispatch=1;
1478 }
1479 else
1480 {
1481 /* Alert sent to BIO. If it is important, flush it now.
1482 * If the message does not get sent due to non-blocking IO,
1483 * we will not worry too much. */
1484 if (s->s3->send_alert[0] == SSL3_AL_FATAL)
1485 (void)BIO_flush(s->wbio);
1486
1487 if (s->msg_callback)
1488 s->msg_callback(1, s->version, SSL3_RT_ALERT, s->s3->send_alert, 2, s, s->msg_callback_arg);
1489
1490 if (s->info_callback != NULL)
1491 cb=s->info_callback;
1492 else if (s->ctx->info_callback != NULL)
1493 cb=s->ctx->info_callback;
1494
1495 if (cb != NULL)
1496 {
1497 j=(s->s3->send_alert[0]<<8)|s->s3->send_alert[1];
1498 cb(s,SSL_CB_WRITE_ALERT,j);
1499 }
1500 }
1501 return(i);
1502 }
1503