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ssl3_read_bytes bug fix
[thirdparty/openssl.git] / ssl / s3_pkt.c
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) 1998-2001 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 <openssl/evp.h>
116 #include <openssl/buffer.h>
117 #include "ssl_locl.h"
118
119 static int do_ssl3_write(SSL *s, int type, const unsigned char *buf,
120 unsigned int len);
121 static int ssl3_write_pending(SSL *s, int type, const unsigned char *buf,
122 unsigned int len);
123 static int ssl3_get_record(SSL *s);
124 static int do_compress(SSL *ssl);
125 static int do_uncompress(SSL *ssl);
126 static int do_change_cipher_spec(SSL *ssl);
127
128 /* used only by ssl3_get_record */
129 static int ssl3_read_n(SSL *s, int n, int max, int extend)
130 {
131 /* If extend == 0, obtain new n-byte packet; if extend == 1, increase
132 * packet by another n bytes.
133 * The packet will be in the sub-array of s->s3->rbuf.buf specified
134 * by s->packet and s->packet_length.
135 * (If s->read_ahead is set, 'max' bytes may be stored in rbuf
136 * [plus s->packet_length bytes if extend == 1].)
137 */
138 int i,off,newb;
139
140 if (!extend)
141 {
142 /* start with empty packet ... */
143 if (s->s3->rbuf.left == 0)
144 s->s3->rbuf.offset = 0;
145 s->packet = s->s3->rbuf.buf + s->s3->rbuf.offset;
146 s->packet_length = 0;
147 /* ... now we can act as if 'extend' was set */
148 }
149
150 /* if there is enough in the buffer from a previous read, take some */
151 if (s->s3->rbuf.left >= (int)n)
152 {
153 s->packet_length+=n;
154 s->s3->rbuf.left-=n;
155 s->s3->rbuf.offset+=n;
156 return(n);
157 }
158
159 /* else we need to read more data */
160 if (!s->read_ahead)
161 max=n;
162
163 {
164 /* avoid buffer overflow */
165 int max_max = SSL3_RT_MAX_PACKET_SIZE - s->packet_length;
166 if (s->options & SSL_OP_MICROSOFT_BIG_SSLV3_BUFFER)
167 max_max += SSL3_RT_MAX_EXTRA;
168 if (max > max_max)
169 max = max_max;
170 }
171 if (n > max) /* does not happen */
172 {
173 SSLerr(SSL_F_SSL3_READ_N,ERR_R_INTERNAL_ERROR);
174 return -1;
175 }
176
177 off = s->packet_length;
178 newb = s->s3->rbuf.left;
179 /* Move any available bytes to front of buffer:
180 * 'off' bytes already pointed to by 'packet',
181 * 'newb' extra ones at the end */
182 if (s->packet != s->s3->rbuf.buf)
183 {
184 /* off > 0 */
185 memmove(s->s3->rbuf.buf, s->packet, off+newb);
186 s->packet = s->s3->rbuf.buf;
187 }
188
189 while (newb < n)
190 {
191 /* Now we have off+newb bytes at the front of s->s3->rbuf.buf and need
192 * to read in more until we have off+n (up to off+max if possible) */
193
194 clear_sys_error();
195 if (s->rbio != NULL)
196 {
197 s->rwstate=SSL_READING;
198 i=BIO_read(s->rbio, &(s->s3->rbuf.buf[off+newb]), max-newb);
199 }
200 else
201 {
202 SSLerr(SSL_F_SSL3_READ_N,SSL_R_READ_BIO_NOT_SET);
203 i = -1;
204 }
205
206 if (i <= 0)
207 {
208 s->s3->rbuf.left = newb;
209 return(i);
210 }
211 newb+=i;
212 }
213
214 /* done reading, now the book-keeping */
215 s->s3->rbuf.offset = off + n;
216 s->s3->rbuf.left = newb - n;
217 s->packet_length += n;
218 s->rwstate=SSL_NOTHING;
219 return(n);
220 }
221
222 /* Call this to get a new input record.
223 * It will return <= 0 if more data is needed, normally due to an error
224 * or non-blocking IO.
225 * When it finishes, one packet has been decoded and can be found in
226 * ssl->s3->rrec.type - is the type of record
227 * ssl->s3->rrec.data, - data
228 * ssl->s3->rrec.length, - number of bytes
229 */
230 /* used only by ssl3_read_bytes */
231 static int ssl3_get_record(SSL *s)
232 {
233 int ssl_major,ssl_minor,al;
234 int enc_err,n,i,ret= -1;
235 SSL3_RECORD *rr;
236 SSL_SESSION *sess;
237 unsigned char *p;
238 unsigned char md[EVP_MAX_MD_SIZE];
239 short version;
240 unsigned int mac_size;
241 int clear=0,extra;
242
243 rr= &(s->s3->rrec);
244 sess=s->session;
245
246 if (s->options & SSL_OP_MICROSOFT_BIG_SSLV3_BUFFER)
247 extra=SSL3_RT_MAX_EXTRA;
248 else
249 extra=0;
250
251 again:
252 /* check if we have the header */
253 if ( (s->rstate != SSL_ST_READ_BODY) ||
254 (s->packet_length < SSL3_RT_HEADER_LENGTH))
255 {
256 n=ssl3_read_n(s,SSL3_RT_HEADER_LENGTH,
257 SSL3_RT_MAX_PACKET_SIZE,0);
258 if (n <= 0) return(n); /* error or non-blocking */
259 s->rstate=SSL_ST_READ_BODY;
260
261 p=s->packet;
262
263 /* Pull apart the header into the SSL3_RECORD */
264 rr->type= *(p++);
265 ssl_major= *(p++);
266 ssl_minor= *(p++);
267 version=(ssl_major<<8)|ssl_minor;
268 n2s(p,rr->length);
269
270 /* Lets check version */
271 if (s->first_packet)
272 {
273 s->first_packet=0;
274 }
275 else
276 {
277 if (version != s->version)
278 {
279 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_WRONG_VERSION_NUMBER);
280 /* Send back error using their
281 * version number :-) */
282 s->version=version;
283 al=SSL_AD_PROTOCOL_VERSION;
284 goto f_err;
285 }
286 }
287
288 if ((version>>8) != SSL3_VERSION_MAJOR)
289 {
290 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_WRONG_VERSION_NUMBER);
291 goto err;
292 }
293
294 if (rr->length >
295 (unsigned int)SSL3_RT_MAX_ENCRYPTED_LENGTH+extra)
296 {
297 al=SSL_AD_RECORD_OVERFLOW;
298 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_PACKET_LENGTH_TOO_LONG);
299 goto f_err;
300 }
301
302 /* now s->rstate == SSL_ST_READ_BODY */
303 }
304
305 /* s->rstate == SSL_ST_READ_BODY, get and decode the data */
306
307 if (rr->length > (s->packet_length-SSL3_RT_HEADER_LENGTH))
308 {
309 /* now s->packet_length == SSL3_RT_HEADER_LENGTH */
310 i=rr->length;
311 n=ssl3_read_n(s,i,i,1);
312 if (n <= 0) return(n); /* error or non-blocking io */
313 /* now n == rr->length,
314 * and s->packet_length == SSL3_RT_HEADER_LENGTH + rr->length */
315 }
316
317 s->rstate=SSL_ST_READ_HEADER; /* set state for later operations */
318
319 /* At this point, s->packet_length == SSL3_RT_HEADER_LNGTH + rr->length,
320 * and we have that many bytes in s->packet
321 */
322 rr->input= &(s->packet[SSL3_RT_HEADER_LENGTH]);
323
324 /* ok, we can now read from 's->packet' data into 'rr'
325 * rr->input points at rr->length bytes, which
326 * need to be copied into rr->data by either
327 * the decryption or by the decompression
328 * When the data is 'copied' into the rr->data buffer,
329 * rr->input will be pointed at the new buffer */
330
331 /* We now have - encrypted [ MAC [ compressed [ plain ] ] ]
332 * rr->length bytes of encrypted compressed stuff. */
333
334 /* check is not needed I believe */
335 if (rr->length > (unsigned int)SSL3_RT_MAX_ENCRYPTED_LENGTH+extra)
336 {
337 al=SSL_AD_RECORD_OVERFLOW;
338 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_ENCRYPTED_LENGTH_TOO_LONG);
339 goto f_err;
340 }
341
342 /* decrypt in place in 'rr->input' */
343 rr->data=rr->input;
344
345 enc_err = s->method->ssl3_enc->enc(s,0);
346 if (enc_err <= 0)
347 {
348 if (enc_err == 0)
349 /* SSLerr() and ssl3_send_alert() have been called */
350 goto err;
351
352 /* otherwise enc_err == -1 */
353 goto decryption_failed_or_bad_record_mac;
354 }
355
356 #ifdef TLS_DEBUG
357 printf("dec %d\n",rr->length);
358 { unsigned int z; for (z=0; z<rr->length; z++) printf("%02X%c",rr->data[z],((z+1)%16)?' ':'\n'); }
359 printf("\n");
360 #endif
361
362 /* r->length is now the compressed data plus mac */
363 if ( (sess == NULL) ||
364 (s->enc_read_ctx == NULL) ||
365 (s->read_hash == NULL))
366 clear=1;
367
368 if (!clear)
369 {
370 mac_size=EVP_MD_size(s->read_hash);
371
372 if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH+extra+mac_size)
373 {
374 #if 0 /* OK only for stream ciphers (then rr->length is visible from ciphertext anyway) */
375 al=SSL_AD_RECORD_OVERFLOW;
376 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_PRE_MAC_LENGTH_TOO_LONG);
377 goto f_err;
378 #else
379 goto decryption_failed_or_bad_record_mac;
380 #endif
381 }
382 /* check the MAC for rr->input (it's in mac_size bytes at the tail) */
383 if (rr->length < mac_size)
384 {
385 #if 0 /* OK only for stream ciphers */
386 al=SSL_AD_DECODE_ERROR;
387 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_LENGTH_TOO_SHORT);
388 goto f_err;
389 #else
390 goto decryption_failed_or_bad_record_mac;
391 #endif
392 }
393 rr->length-=mac_size;
394 i=s->method->ssl3_enc->mac(s,md,0);
395 if (memcmp(md,&(rr->data[rr->length]),mac_size) != 0)
396 {
397 goto decryption_failed_or_bad_record_mac;
398 }
399 }
400
401 /* r->length is now just compressed */
402 if (s->expand != NULL)
403 {
404 if (rr->length >
405 (unsigned int)SSL3_RT_MAX_COMPRESSED_LENGTH+extra)
406 {
407 al=SSL_AD_RECORD_OVERFLOW;
408 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_COMPRESSED_LENGTH_TOO_LONG);
409 goto f_err;
410 }
411 if (!do_uncompress(s))
412 {
413 al=SSL_AD_DECOMPRESSION_FAILURE;
414 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_BAD_DECOMPRESSION);
415 goto f_err;
416 }
417 }
418
419 if (rr->length > (unsigned int)SSL3_RT_MAX_PLAIN_LENGTH+extra)
420 {
421 al=SSL_AD_RECORD_OVERFLOW;
422 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_DATA_LENGTH_TOO_LONG);
423 goto f_err;
424 }
425
426 rr->off=0;
427 /* So at this point the following is true
428 * ssl->s3->rrec.type is the type of record
429 * ssl->s3->rrec.length == number of bytes in record
430 * ssl->s3->rrec.off == offset to first valid byte
431 * ssl->s3->rrec.data == where to take bytes from, increment
432 * after use :-).
433 */
434
435 /* we have pulled in a full packet so zero things */
436 s->packet_length=0;
437
438 /* just read a 0 length packet */
439 if (rr->length == 0) goto again;
440
441 return(1);
442
443 decryption_failed_or_bad_record_mac:
444 /* Separate 'decryption_failed' alert was introduced with TLS 1.0,
445 * SSL 3.0 only has 'bad_record_mac'. But unless a decryption
446 * failure is directly visible from the ciphertext anyway,
447 * we should not reveal which kind of error occured -- this
448 * might become visible to an attacker (e.g. via logfile) */
449 al=SSL_AD_BAD_RECORD_MAC;
450 SSLerr(SSL_F_SSL3_GET_RECORD,SSL_R_DECRYPTION_FAILED_OR_BAD_RECORD_MAC);
451 f_err:
452 ssl3_send_alert(s,SSL3_AL_FATAL,al);
453 err:
454 return(ret);
455 }
456
457 static int do_uncompress(SSL *ssl)
458 {
459 int i;
460 SSL3_RECORD *rr;
461
462 rr= &(ssl->s3->rrec);
463 i=COMP_expand_block(ssl->expand,rr->comp,
464 SSL3_RT_MAX_PLAIN_LENGTH,rr->data,(int)rr->length);
465 if (i < 0)
466 return(0);
467 else
468 rr->length=i;
469 rr->data=rr->comp;
470
471 return(1);
472 }
473
474 static int do_compress(SSL *ssl)
475 {
476 int i;
477 SSL3_RECORD *wr;
478
479 wr= &(ssl->s3->wrec);
480 i=COMP_compress_block(ssl->compress,wr->data,
481 SSL3_RT_MAX_COMPRESSED_LENGTH,
482 wr->input,(int)wr->length);
483 if (i < 0)
484 return(0);
485 else
486 wr->length=i;
487
488 wr->input=wr->data;
489 return(1);
490 }
491
492 /* Call this to write data in records of type 'type'
493 * It will return <= 0 if not all data has been sent or non-blocking IO.
494 */
495 int ssl3_write_bytes(SSL *s, int type, const void *buf_, int len)
496 {
497 const unsigned char *buf=buf_;
498 unsigned int tot,n,nw;
499 int i;
500
501 s->rwstate=SSL_NOTHING;
502 tot=s->s3->wnum;
503 s->s3->wnum=0;
504
505 if (SSL_in_init(s) && !s->in_handshake)
506 {
507 i=s->handshake_func(s);
508 if (i < 0) return(i);
509 if (i == 0)
510 {
511 SSLerr(SSL_F_SSL3_WRITE_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
512 return(-1);
513 }
514 }
515
516 n=(len-tot);
517 for (;;)
518 {
519 if (n > SSL3_RT_MAX_PLAIN_LENGTH)
520 nw=SSL3_RT_MAX_PLAIN_LENGTH;
521 else
522 nw=n;
523
524 i=do_ssl3_write(s,type,&(buf[tot]),nw);
525 if (i <= 0)
526 {
527 s->s3->wnum=tot;
528 return(i);
529 }
530
531 if ((i == (int)n) ||
532 (type == SSL3_RT_APPLICATION_DATA &&
533 (s->mode & SSL_MODE_ENABLE_PARTIAL_WRITE)))
534 {
535 return(tot+i);
536 }
537
538 n-=i;
539 tot+=i;
540 }
541 }
542
543 static int do_ssl3_write(SSL *s, int type, const unsigned char *buf,
544 unsigned int len)
545 {
546 unsigned char *p,*plen;
547 int i,mac_size,clear=0;
548 SSL3_RECORD *wr;
549 SSL3_BUFFER *wb;
550 SSL_SESSION *sess;
551
552 /* first check is there is a SSL3_RECORD still being written
553 * out. This will happen with non blocking IO */
554 if (s->s3->wbuf.left != 0)
555 return(ssl3_write_pending(s,type,buf,len));
556
557 /* If we have an alert to send, lets send it */
558 if (s->s3->alert_dispatch)
559 {
560 i=ssl3_dispatch_alert(s);
561 if (i <= 0)
562 return(i);
563 /* if it went, fall through and send more stuff */
564 }
565
566 if (len == 0) return(len);
567
568 wr= &(s->s3->wrec);
569 wb= &(s->s3->wbuf);
570 sess=s->session;
571
572 if ( (sess == NULL) ||
573 (s->enc_write_ctx == NULL) ||
574 (s->write_hash == NULL))
575 clear=1;
576
577 if (clear)
578 mac_size=0;
579 else
580 mac_size=EVP_MD_size(s->write_hash);
581
582 p=wb->buf;
583
584 /* write the header */
585 *(p++)=type&0xff;
586 wr->type=type;
587
588 *(p++)=(s->version>>8);
589 *(p++)=s->version&0xff;
590
591 /* record where we are to write out packet length */
592 plen=p;
593 p+=2;
594
595 /* lets setup the record stuff. */
596 wr->data=p;
597 wr->length=(int)len;
598 wr->input=(unsigned char *)buf;
599
600 /* we now 'read' from wr->input, wr->length bytes into
601 * wr->data */
602
603 /* first we compress */
604 if (s->compress != NULL)
605 {
606 if (!do_compress(s))
607 {
608 SSLerr(SSL_F_DO_SSL3_WRITE,SSL_R_COMPRESSION_FAILURE);
609 goto err;
610 }
611 }
612 else
613 {
614 memcpy(wr->data,wr->input,wr->length);
615 wr->input=wr->data;
616 }
617
618 /* we should still have the output to wr->data and the input
619 * from wr->input. Length should be wr->length.
620 * wr->data still points in the wb->buf */
621
622 if (mac_size != 0)
623 {
624 s->method->ssl3_enc->mac(s,&(p[wr->length]),1);
625 wr->length+=mac_size;
626 wr->input=p;
627 wr->data=p;
628 }
629
630 /* ssl3_enc can only have an error on read */
631 s->method->ssl3_enc->enc(s,1);
632
633 /* record length after mac and block padding */
634 s2n(wr->length,plen);
635
636 /* we should now have
637 * wr->data pointing to the encrypted data, which is
638 * wr->length long */
639 wr->type=type; /* not needed but helps for debugging */
640 wr->length+=SSL3_RT_HEADER_LENGTH;
641
642 /* Now lets setup wb */
643 wb->left=wr->length;
644 wb->offset=0;
645
646 s->s3->wpend_tot=len;
647 s->s3->wpend_buf=buf;
648 s->s3->wpend_type=type;
649 s->s3->wpend_ret=len;
650
651 /* we now just need to write the buffer */
652 return(ssl3_write_pending(s,type,buf,len));
653 err:
654 return(-1);
655 }
656
657 /* if s->s3->wbuf.left != 0, we need to call this */
658 static int ssl3_write_pending(SSL *s, int type, const unsigned char *buf,
659 unsigned int len)
660 {
661 int i;
662
663 /* XXXX */
664 if ((s->s3->wpend_tot > (int)len)
665 || ((s->s3->wpend_buf != buf) &&
666 !(s->mode & SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER))
667 || (s->s3->wpend_type != type))
668 {
669 SSLerr(SSL_F_SSL3_WRITE_PENDING,SSL_R_BAD_WRITE_RETRY);
670 return(-1);
671 }
672
673 for (;;)
674 {
675 clear_sys_error();
676 if (s->wbio != NULL)
677 {
678 s->rwstate=SSL_WRITING;
679 i=BIO_write(s->wbio,
680 (char *)&(s->s3->wbuf.buf[s->s3->wbuf.offset]),
681 (unsigned int)s->s3->wbuf.left);
682 }
683 else
684 {
685 SSLerr(SSL_F_SSL3_WRITE_PENDING,SSL_R_BIO_NOT_SET);
686 i= -1;
687 }
688 if (i == s->s3->wbuf.left)
689 {
690 s->s3->wbuf.left=0;
691 s->rwstate=SSL_NOTHING;
692 return(s->s3->wpend_ret);
693 }
694 else if (i <= 0)
695 return(i);
696 s->s3->wbuf.offset+=i;
697 s->s3->wbuf.left-=i;
698 }
699 }
700
701 /* Return up to 'len' payload bytes received in 'type' records.
702 * 'type' is one of the following:
703 *
704 * - SSL3_RT_HANDSHAKE (when ssl3_get_message calls us)
705 * - SSL3_RT_APPLICATION_DATA (when ssl3_read calls us)
706 * - 0 (during a shutdown, no data has to be returned)
707 *
708 * If we don't have stored data to work from, read a SSL/TLS record first
709 * (possibly multiple records if we still don't have anything to return).
710 *
711 * This function must handle any surprises the peer may have for us, such as
712 * Alert records (e.g. close_notify), ChangeCipherSpec records (not really
713 * a surprise, but handled as if it were), or renegotiation requests.
714 * Also if record payloads contain fragments too small to process, we store
715 * them until there is enough for the respective protocol (the record protocol
716 * may use arbitrary fragmentation and even interleaving):
717 * Change cipher spec protocol
718 * just 1 byte needed, no need for keeping anything stored
719 * Alert protocol
720 * 2 bytes needed (AlertLevel, AlertDescription)
721 * Handshake protocol
722 * 4 bytes needed (HandshakeType, uint24 length) -- we just have
723 * to detect unexpected Client Hello and Hello Request messages
724 * here, anything else is handled by higher layers
725 * Application data protocol
726 * none of our business
727 */
728 int ssl3_read_bytes(SSL *s, int type, unsigned char *buf, int len, int peek)
729 {
730 int al,i,j,ret;
731 unsigned int n;
732 SSL3_RECORD *rr;
733 void (*cb)()=NULL;
734
735 if (s->s3->rbuf.buf == NULL) /* Not initialized yet */
736 if (!ssl3_setup_buffers(s))
737 return(-1);
738
739 if ((type && (type != SSL3_RT_APPLICATION_DATA) && (type != SSL3_RT_HANDSHAKE) && type) ||
740 (peek && (type != SSL3_RT_APPLICATION_DATA)))
741 {
742 SSLerr(SSL_F_SSL3_READ_BYTES, ERR_R_INTERNAL_ERROR);
743 return -1;
744 }
745
746 if ((type == SSL3_RT_HANDSHAKE) && (s->s3->handshake_fragment_len > 0))
747 /* (partially) satisfy request from storage */
748 {
749 unsigned char *src = s->s3->handshake_fragment;
750 unsigned char *dst = buf;
751 unsigned int k;
752
753 /* peek == 0 */
754 n = 0;
755 while ((len > 0) && (s->s3->handshake_fragment_len > 0))
756 {
757 *dst++ = *src++;
758 len--; s->s3->handshake_fragment_len--;
759 n++;
760 }
761 /* move any remaining fragment bytes: */
762 for (k = 0; k < s->s3->handshake_fragment_len; k++)
763 s->s3->handshake_fragment[k] = *src++;
764 return n;
765 }
766
767 /* Now s->s3->handshake_fragment_len == 0 if type == SSL3_RT_HANDSHAKE. */
768
769 if (!s->in_handshake && SSL_in_init(s))
770 {
771 /* type == SSL3_RT_APPLICATION_DATA */
772 i=s->handshake_func(s);
773 if (i < 0) return(i);
774 if (i == 0)
775 {
776 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
777 return(-1);
778 }
779 }
780 start:
781 s->rwstate=SSL_NOTHING;
782
783 /* s->s3->rrec.type - is the type of record
784 * s->s3->rrec.data, - data
785 * s->s3->rrec.off, - offset into 'data' for next read
786 * s->s3->rrec.length, - number of bytes. */
787 rr = &(s->s3->rrec);
788
789 /* get new packet if necessary */
790 if ((rr->length == 0) || (s->rstate == SSL_ST_READ_BODY))
791 {
792 ret=ssl3_get_record(s);
793 if (ret <= 0) return(ret);
794 }
795
796 /* we now have a packet which can be read and processed */
797
798 if (s->s3->change_cipher_spec /* set when we receive ChangeCipherSpec,
799 * reset by ssl3_get_finished */
800 && (rr->type != SSL3_RT_HANDSHAKE))
801 {
802 al=SSL_AD_UNEXPECTED_MESSAGE;
803 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_DATA_BETWEEN_CCS_AND_FINISHED);
804 goto err;
805 }
806
807 /* If the other end has shut down, throw anything we read away
808 * (even in 'peek' mode) */
809 if (s->shutdown & SSL_RECEIVED_SHUTDOWN)
810 {
811 rr->length=0;
812 s->rwstate=SSL_NOTHING;
813 return(0);
814 }
815
816
817 if (type == rr->type) /* SSL3_RT_APPLICATION_DATA or SSL3_RT_HANDSHAKE */
818 {
819 /* make sure that we are not getting application data when we
820 * are doing a handshake for the first time */
821 if (SSL_in_init(s) && (type == SSL3_RT_APPLICATION_DATA) &&
822 (s->enc_read_ctx == NULL))
823 {
824 al=SSL_AD_UNEXPECTED_MESSAGE;
825 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_APP_DATA_IN_HANDSHAKE);
826 goto f_err;
827 }
828
829 if (len <= 0) return(len);
830
831 if ((unsigned int)len > rr->length)
832 n = rr->length;
833 else
834 n = (unsigned int)len;
835
836 memcpy(buf,&(rr->data[rr->off]),n);
837 if (!peek)
838 {
839 rr->length-=n;
840 rr->off+=n;
841 if (rr->length == 0)
842 {
843 s->rstate=SSL_ST_READ_HEADER;
844 rr->off=0;
845 }
846 }
847 return(n);
848 }
849
850
851 /* If we get here, then type != rr->type; if we have a handshake
852 * message, then it was unexpected (Hello Request or Client Hello). */
853
854 /* In case of record types for which we have 'fragment' storage,
855 * fill that so that we can process the data at a fixed place.
856 */
857 {
858 unsigned int dest_maxlen = 0;
859 unsigned char *dest = NULL;
860 unsigned int *dest_len = NULL;
861
862 if (rr->type == SSL3_RT_HANDSHAKE)
863 {
864 dest_maxlen = sizeof s->s3->handshake_fragment;
865 dest = s->s3->handshake_fragment;
866 dest_len = &s->s3->handshake_fragment_len;
867 }
868 else if (rr->type == SSL3_RT_ALERT)
869 {
870 dest_maxlen = sizeof s->s3->alert_fragment;
871 dest = s->s3->alert_fragment;
872 dest_len = &s->s3->alert_fragment_len;
873 }
874
875 if (dest_maxlen > 0)
876 {
877 n = dest_maxlen - *dest_len; /* available space in 'dest' */
878 if (rr->length < n)
879 n = rr->length; /* available bytes */
880
881 /* now move 'n' bytes: */
882 while (n-- > 0)
883 {
884 dest[(*dest_len)++] = rr->data[rr->off++];
885 rr->length--;
886 }
887
888 if (*dest_len < dest_maxlen)
889 goto start; /* fragment was too small */
890 }
891 }
892
893 /* s->s3->handshake_fragment_len == 4 iff rr->type == SSL3_RT_HANDSHAKE;
894 * s->s3->alert_fragment_len == 2 iff rr->type == SSL3_RT_ALERT.
895 * (Possibly rr is 'empty' now, i.e. rr->length may be 0.) */
896
897 /* If we are a client, check for an incoming 'Hello Request': */
898 if ((!s->server) &&
899 (s->s3->handshake_fragment_len >= 4) &&
900 (s->s3->handshake_fragment[0] == SSL3_MT_HELLO_REQUEST) &&
901 (s->session != NULL) && (s->session->cipher != NULL))
902 {
903 s->s3->handshake_fragment_len = 0;
904
905 if ((s->s3->handshake_fragment[1] != 0) ||
906 (s->s3->handshake_fragment[2] != 0) ||
907 (s->s3->handshake_fragment[3] != 0))
908 {
909 al=SSL_AD_DECODE_ERROR;
910 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_BAD_HELLO_REQUEST);
911 goto err;
912 }
913
914 if (s->msg_callback)
915 s->msg_callback(0, s->version, SSL3_RT_HANDSHAKE, s->s3->handshake_fragment, 4, s, s->msg_callback_arg);
916
917 if (SSL_is_init_finished(s) &&
918 !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS) &&
919 !s->s3->renegotiate)
920 {
921 ssl3_renegotiate(s);
922 if (ssl3_renegotiate_check(s))
923 {
924 i=s->handshake_func(s);
925 if (i < 0) return(i);
926 if (i == 0)
927 {
928 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
929 return(-1);
930 }
931
932 if (!(s->mode & SSL_MODE_AUTO_RETRY))
933 {
934 if (s->s3->rbuf.left == 0) /* no read-ahead left? */
935 {
936 BIO *bio;
937 /* In the case where we try to read application data,
938 * but we trigger an SSL handshake, we return -1 with
939 * the retry option set. Otherwise renegotiation may
940 * cause nasty problems in the blocking world */
941 s->rwstate=SSL_READING;
942 bio=SSL_get_rbio(s);
943 BIO_clear_retry_flags(bio);
944 BIO_set_retry_read(bio);
945 return(-1);
946 }
947 }
948 }
949 }
950 /* we either finished a handshake or ignored the request,
951 * now try again to obtain the (application) data we were asked for */
952 goto start;
953 }
954
955 if (s->s3->alert_fragment_len >= 2)
956 {
957 int alert_level = s->s3->alert_fragment[0];
958 int alert_descr = s->s3->alert_fragment[1];
959
960 s->s3->alert_fragment_len = 0;
961
962 if (s->msg_callback)
963 s->msg_callback(0, s->version, SSL3_RT_ALERT, s->s3->alert_fragment, 2, s, s->msg_callback_arg);
964
965 if (s->info_callback != NULL)
966 cb=s->info_callback;
967 else if (s->ctx->info_callback != NULL)
968 cb=s->ctx->info_callback;
969
970 if (cb != NULL)
971 {
972 j = (alert_level << 8) | alert_descr;
973 cb(s, SSL_CB_READ_ALERT, j);
974 }
975
976 if (alert_level == 1) /* warning */
977 {
978 s->s3->warn_alert = alert_descr;
979 if (alert_descr == SSL_AD_CLOSE_NOTIFY)
980 {
981 s->shutdown |= SSL_RECEIVED_SHUTDOWN;
982 return(0);
983 }
984 }
985 else if (alert_level == 2) /* fatal */
986 {
987 char tmp[16];
988
989 s->rwstate=SSL_NOTHING;
990 s->s3->fatal_alert = alert_descr;
991 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_AD_REASON_OFFSET + alert_descr);
992 BIO_snprintf(tmp,sizeof tmp,"%d",alert_descr);
993 ERR_add_error_data(2,"SSL alert number ",tmp);
994 s->shutdown|=SSL_RECEIVED_SHUTDOWN;
995 SSL_CTX_remove_session(s->ctx,s->session);
996 return(0);
997 }
998 else
999 {
1000 al=SSL_AD_ILLEGAL_PARAMETER;
1001 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNKNOWN_ALERT_TYPE);
1002 goto f_err;
1003 }
1004
1005 goto start;
1006 }
1007
1008 if (s->shutdown & SSL_SENT_SHUTDOWN) /* but we have not received a shutdown */
1009 {
1010 s->rwstate=SSL_NOTHING;
1011 rr->length=0;
1012 return(0);
1013 }
1014
1015 if (rr->type == SSL3_RT_CHANGE_CIPHER_SPEC)
1016 {
1017 /* 'Change Cipher Spec' is just a single byte, so we know
1018 * exactly what the record payload has to look like */
1019 if ( (rr->length != 1) || (rr->off != 0) ||
1020 (rr->data[0] != SSL3_MT_CCS))
1021 {
1022 i=SSL_AD_ILLEGAL_PARAMETER;
1023 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_BAD_CHANGE_CIPHER_SPEC);
1024 goto err;
1025 }
1026
1027 rr->length=0;
1028
1029 if (s->msg_callback)
1030 s->msg_callback(0, s->version, SSL3_RT_CHANGE_CIPHER_SPEC, rr->data, 1, s, s->msg_callback_arg);
1031
1032 s->s3->change_cipher_spec=1;
1033 if (!do_change_cipher_spec(s))
1034 goto err;
1035 else
1036 goto start;
1037 }
1038
1039 /* Unexpected handshake message (Client Hello, or protocol violation) */
1040 if ((s->s3->handshake_fragment_len >= 4) && !s->in_handshake)
1041 {
1042 if (((s->state&SSL_ST_MASK) == SSL_ST_OK) &&
1043 !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS))
1044 {
1045 #if 0 /* worked only because C operator preferences are not as expected (and
1046 * because this is not really needed for clients except for detecting
1047 * protocol violations): */
1048 s->state=SSL_ST_BEFORE|(s->server)
1049 ?SSL_ST_ACCEPT
1050 :SSL_ST_CONNECT;
1051 #else
1052 s->state = s->server ? SSL_ST_ACCEPT : SSL_ST_CONNECT;
1053 #endif
1054 s->new_session=1;
1055 }
1056 i=s->handshake_func(s);
1057 if (i < 0) return(i);
1058 if (i == 0)
1059 {
1060 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_SSL_HANDSHAKE_FAILURE);
1061 return(-1);
1062 }
1063
1064 if (!(s->mode & SSL_MODE_AUTO_RETRY))
1065 {
1066 if (s->s3->rbuf.left == 0) /* no read-ahead left? */
1067 {
1068 BIO *bio;
1069 /* In the case where we try to read application data,
1070 * but we trigger an SSL handshake, we return -1 with
1071 * the retry option set. Otherwise renegotiation may
1072 * cause nasty problems in the blocking world */
1073 s->rwstate=SSL_READING;
1074 bio=SSL_get_rbio(s);
1075 BIO_clear_retry_flags(bio);
1076 BIO_set_retry_read(bio);
1077 return(-1);
1078 }
1079 }
1080 goto start;
1081 }
1082
1083 switch (rr->type)
1084 {
1085 default:
1086 #ifndef OPENSSL_NO_TLS
1087 /* TLS just ignores unknown message types */
1088 if (s->version == TLS1_VERSION)
1089 {
1090 rr->length = 0;
1091 goto start;
1092 }
1093 #endif
1094 al=SSL_AD_UNEXPECTED_MESSAGE;
1095 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNEXPECTED_RECORD);
1096 goto f_err;
1097 case SSL3_RT_CHANGE_CIPHER_SPEC:
1098 case SSL3_RT_ALERT:
1099 case SSL3_RT_HANDSHAKE:
1100 /* we already handled all of these, with the possible exception
1101 * of SSL3_RT_HANDSHAKE when s->in_handshake is set, but that
1102 * should not happen when type != rr->type */
1103 al=SSL_AD_UNEXPECTED_MESSAGE;
1104 SSLerr(SSL_F_SSL3_READ_BYTES,ERR_R_INTERNAL_ERROR);
1105 goto f_err;
1106 case SSL3_RT_APPLICATION_DATA:
1107 /* At this point, we were expecting handshake data,
1108 * but have application data. If the library was
1109 * running inside ssl3_read() (i.e. in_read_app_data
1110 * is set) and it makes sense to read application data
1111 * at this point (session renegotiation not yet started),
1112 * we will indulge it.
1113 */
1114 if (s->s3->in_read_app_data &&
1115 (s->s3->total_renegotiations != 0) &&
1116 ((
1117 (s->state & SSL_ST_CONNECT) &&
1118 (s->state >= SSL3_ST_CW_CLNT_HELLO_A) &&
1119 (s->state <= SSL3_ST_CR_SRVR_HELLO_A)
1120 ) || (
1121 (s->state & SSL_ST_ACCEPT) &&
1122 (s->state <= SSL3_ST_SW_HELLO_REQ_A) &&
1123 (s->state >= SSL3_ST_SR_CLNT_HELLO_A)
1124 )
1125 ))
1126 {
1127 s->s3->in_read_app_data=0;
1128 return(-1);
1129 }
1130 else
1131 {
1132 al=SSL_AD_UNEXPECTED_MESSAGE;
1133 SSLerr(SSL_F_SSL3_READ_BYTES,SSL_R_UNEXPECTED_RECORD);
1134 goto f_err;
1135 }
1136 }
1137 /* not reached */
1138
1139 f_err:
1140 ssl3_send_alert(s,SSL3_AL_FATAL,al);
1141 err:
1142 return(-1);
1143 }
1144
1145 static int do_change_cipher_spec(SSL *s)
1146 {
1147 int i;
1148 const char *sender;
1149 int slen;
1150
1151 if (s->state & SSL_ST_ACCEPT)
1152 i=SSL3_CHANGE_CIPHER_SERVER_READ;
1153 else
1154 i=SSL3_CHANGE_CIPHER_CLIENT_READ;
1155
1156 if (s->s3->tmp.key_block == NULL)
1157 {
1158 s->session->cipher=s->s3->tmp.new_cipher;
1159 if (!s->method->ssl3_enc->setup_key_block(s)) return(0);
1160 }
1161
1162 if (!s->method->ssl3_enc->change_cipher_state(s,i))
1163 return(0);
1164
1165 /* we have to record the message digest at
1166 * this point so we can get it before we read
1167 * the finished message */
1168 if (s->state & SSL_ST_CONNECT)
1169 {
1170 sender=s->method->ssl3_enc->server_finished_label;
1171 slen=s->method->ssl3_enc->server_finished_label_len;
1172 }
1173 else
1174 {
1175 sender=s->method->ssl3_enc->client_finished_label;
1176 slen=s->method->ssl3_enc->client_finished_label_len;
1177 }
1178
1179 s->s3->tmp.peer_finish_md_len = s->method->ssl3_enc->final_finish_mac(s,
1180 &(s->s3->finish_dgst1),
1181 &(s->s3->finish_dgst2),
1182 sender,slen,s->s3->tmp.peer_finish_md);
1183
1184 return(1);
1185 }
1186
1187 void ssl3_send_alert(SSL *s, int level, int desc)
1188 {
1189 /* Map tls/ssl alert value to correct one */
1190 desc=s->method->ssl3_enc->alert_value(desc);
1191 if (s->version == SSL3_VERSION && desc == SSL_AD_PROTOCOL_VERSION)
1192 desc = SSL_AD_HANDSHAKE_FAILURE; /* SSL 3.0 does not have protocol_version alerts */
1193 if (desc < 0) return;
1194 /* If a fatal one, remove from cache */
1195 if ((level == 2) && (s->session != NULL))
1196 SSL_CTX_remove_session(s->ctx,s->session);
1197
1198 s->s3->alert_dispatch=1;
1199 s->s3->send_alert[0]=level;
1200 s->s3->send_alert[1]=desc;
1201 if (s->s3->wbuf.left == 0) /* data still being written out? */
1202 ssl3_dispatch_alert(s);
1203 /* else data is still being written out, we will get written
1204 * some time in the future */
1205 }
1206
1207 int ssl3_dispatch_alert(SSL *s)
1208 {
1209 int i,j;
1210 void (*cb)()=NULL;
1211
1212 s->s3->alert_dispatch=0;
1213 i=do_ssl3_write(s,SSL3_RT_ALERT,&s->s3->send_alert[0],2);
1214 if (i <= 0)
1215 {
1216 s->s3->alert_dispatch=1;
1217 }
1218 else
1219 {
1220 /* Alert sent to BIO. If it is important, flush it now.
1221 * If the message does not get sent due to non-blocking IO,
1222 * we will not worry too much. */
1223 if (s->s3->send_alert[0] == SSL3_AL_FATAL)
1224 (void)BIO_flush(s->wbio);
1225
1226 if (s->msg_callback)
1227 s->msg_callback(1, s->version, SSL3_RT_ALERT, s->s3->send_alert, 2, s, s->msg_callback_arg);
1228
1229 if (s->info_callback != NULL)
1230 cb=s->info_callback;
1231 else if (s->ctx->info_callback != NULL)
1232 cb=s->ctx->info_callback;
1233
1234 if (cb != NULL)
1235 {
1236 j=(s->s3->send_alert[0]<<8)|s->s3->send_alert[1];
1237 cb(s,SSL_CB_WRITE_ALERT,j);
1238 }
1239 }
1240 return(i);
1241 }
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