1 /* ssl/s3_pkt.c */
2 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
3 * All rights reserved.
4 *
5 * This package is an SSL implementation written
6 * by Eric Young (eay@cryptsoft.com).
7 * The implementation was written so as to conform with Netscapes SSL.
8 *
9 * This library is free for commercial and non-commercial use as long as
10 * the following conditions are aheared to. The following conditions
11 * apply to all code found in this distribution, be it the RC4, RSA,
12 * lhash, DES, etc., code; not just the SSL code. The SSL documentation
13 * included with this distribution is covered by the same copyright terms
14 * except that the holder is Tim Hudson (tjh@cryptsoft.com).
15 *
16 * Copyright remains Eric Young's, and as such any Copyright notices in
17 * the code are not to be removed.
18 * If this package is used in a product, Eric Young should be given attribution
19 * as the author of the parts of the library used.
20 * This can be in the form of a textual message at program startup or
21 * in documentation (online or textual) provided with the package.
22 *
23 * Redistribution and use in source and binary forms, with or without
24 * modification, are permitted provided that the following conditions
25 * are met:
26 * 1. Redistributions of source code must retain the copyright
27 * notice, this list of conditions and the following disclaimer.
28 * 2. Redistributions in binary form must reproduce the above copyright
29 * notice, this list of conditions and the following disclaimer in the
30 * documentation and/or other materials provided with the distribution.
31 * 3. All advertising materials mentioning features or use of this software
32 * must display the following acknowledgement:
33 * "This product includes cryptographic software written by
34 * Eric Young (eay@cryptsoft.com)"
35 * The word 'cryptographic' can be left out if the rouines from the library
36 * being used are not cryptographic related :-).
37 * 4. If you include any Windows specific code (or a derivative thereof) from
38 * the apps directory (application code) you must include an acknowledgement:
39 * "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
40 *
41 * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
42 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
43 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
44 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
45 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
46 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
47 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
48 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
49 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
50 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
51 * SUCH DAMAGE.
52 *
53 * The licence and distribution terms for any publically available version or
54 * derivative of this code cannot be changed. i.e. this code cannot simply be
55 * copied and put under another distribution licence
56 * [including the GNU Public Licence.]
57 */
58 /* ====================================================================
59 * Copyright (c) 1998-2002 The OpenSSL Project. All rights reserved.
60 *
61 * Redistribution and use in source and binary forms, with or without
62 * modification, are permitted provided that the following conditions
63 * are met:
64 *
65 * 1. Redistributions of source code must retain the above copyright
66 * notice, this list of conditions and the following disclaimer.
67 *
68 * 2. Redistributions in binary form must reproduce the above copyright
69 * notice, this list of conditions and the following disclaimer in
70 * the documentation and/or other materials provided with the
71 * distribution.
72 *
73 * 3. All advertising materials mentioning features or use of this
74 * software must display the following acknowledgment:
75 * "This product includes software developed by the OpenSSL Project
76 * for use in the OpenSSL Toolkit. (http://www.openssl.org/)"
77 *
78 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
79 * endorse or promote products derived from this software without
80 * prior written permission. For written permission, please contact
81 * openssl-core@openssl.org.
82 *
83 * 5. Products derived from this software may not be called "OpenSSL"
84 * nor may "OpenSSL" appear in their names without prior written
85 * permission of the OpenSSL Project.
86 *
87 * 6. Redistributions of any form whatsoever must retain the following
88 * acknowledgment:
89 * "This product includes software developed by the OpenSSL Project
90 * for use in the OpenSSL Toolkit (http://www.openssl.org/)"
91 *
92 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
93 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
94 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
95 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR
96 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
97 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
98 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
99 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
100 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
101 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
102 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
103 * OF THE POSSIBILITY OF SUCH DAMAGE.
104 * ====================================================================
105 *
106 * This product includes cryptographic software written by Eric Young
107 * (eay@cryptsoft.com). This product includes software written by Tim
108 * Hudson (tjh@cryptsoft.com).
109 *
110 */
111
112 #include <stdio.h>
113 #include <limits.h>
114 #include <errno.h>
115 #define USE_SOCKETS
116 #include "ssl_locl.h"
117 #include <openssl/evp.h>
118 #include <openssl/buffer.h>
119 #include <openssl/rand.h>
120
121 static int do_ssl3_write(SSL *s, int type, const unsigned char *buf,
122 unsigned int len, int create_empty_fragment);
123 static int ssl3_get_record(SSL *s);
124
ssl3_read_n(SSL * s,int n,int max,int extend)125 int ssl3_read_n(SSL *s, int n, int max, int extend)
126 {
127 /*
128 * If extend == 0, obtain new n-byte packet; if extend == 1, increase
129 * packet by another n bytes. The packet will be in the sub-array of
130 * s->s3->rbuf.buf specified by s->packet and s->packet_length. (If
131 * s->read_ahead is set, 'max' bytes may be stored in rbuf [plus
132 * s->packet_length bytes if extend == 1].)
133 */
134 int i, len, left;
135 long align = 0;
136 unsigned char *pkt;
137 SSL3_BUFFER *rb;
138
139 if (n <= 0)
140 return n;
141
142 rb = &(s->s3->rbuf);
143 if (rb->buf == NULL)
144 if (!ssl3_setup_read_buffer(s))
145 return -1;
146
147 left = rb->left;
148 #if defined(SSL3_ALIGN_PAYLOAD) && SSL3_ALIGN_PAYLOAD!=0
149 align = (long)rb->buf + SSL3_RT_HEADER_LENGTH;
150 align = (-align) & (SSL3_ALIGN_PAYLOAD - 1);
151 #endif
152
153 if (!extend) {
154 /* start with empty packet ... */
155 if (left == 0)
156 rb->offset = align;
157 else if (align != 0 && left >= SSL3_RT_HEADER_LENGTH) {
158 /*
159 * check if next packet length is large enough to justify payload
160 * alignment...
161 */
162 pkt = rb->buf + rb->offset;
163 if (pkt[0] == SSL3_RT_APPLICATION_DATA
164 && (pkt[3] << 8 | pkt[4]) >= 128) {
165 /*
166 * Note that even if packet is corrupted and its length field
167 * is insane, we can only be led to wrong decision about
168 * whether memmove will occur or not. Header values has no
169 * effect on memmove arguments and therefore no buffer
170 * overrun can be triggered.
171 */
172 memmove(rb->buf + align, pkt, left);
173 rb->offset = align;
174 }
175 }
176 s->packet = rb->buf + rb->offset;
177 s->packet_length = 0;
178 /* ... now we can act as if 'extend' was set */
179 }
180
181 /*
182 * For DTLS/UDP reads should not span multiple packets because the read
183 * operation returns the whole packet at once (as long as it fits into
184 * the buffer).
185 */
186 if (SSL_version(s) == DTLS1_VERSION || SSL_version(s) == DTLS1_BAD_VER) {
187 if (left == 0 && extend)
188 return 0;
189 if (left > 0 && n > left)
190 n = left;
191 }
192
193 /* if there is enough in the buffer from a previous read, take some */
194 if (left >= n) {
195 s->packet_length += n;
196 rb->left = left - n;
197 rb->offset += n;
198 return (n);
199 }
200
201 /* else we need to read more data */
202
203 len = s->packet_length;
204 pkt = rb->buf + align;
205 /*
206 * Move any available bytes to front of buffer: 'len' bytes already
207 * pointed to by 'packet', 'left' extra ones at the end
208 */
209 if (s->packet != pkt) { /* len > 0 */
210 memmove(pkt, s->packet, len + left);
211 s->packet = pkt;
212 rb->offset = len + align;
213 }
214
215 if (n > (int)(rb->len - rb->offset)) { /* does not happen */
216 SSLerr(SSL_F_SSL3_READ_N, ERR_R_INTERNAL_ERROR);
217 return -1;
218 }
219
220 /* We always act like read_ahead is set for DTLS */
221 if (!s->read_ahead && !SSL_IS_DTLS(s))
222 /* ignore max parameter */
223 max = n;
224 else {
225 if (max < n)
226 max = n;
227 if (max > (int)(rb->len - rb->offset))
228 max = rb->len - rb->offset;
229 }
230
231 while (left < n) {
232 /*
233 * Now we have len+left bytes at the front of s->s3->rbuf.buf and
234 * need to read in more until we have len+n (up to len+max if
235 * possible)
236 */
237
238 clear_sys_error();
239 if (s->rbio != NULL) {
240 s->rwstate = SSL_READING;
241 i = BIO_read(s->rbio, pkt + len + left, max - left);
242 } else {
243 SSLerr(SSL_F_SSL3_READ_N, SSL_R_READ_BIO_NOT_SET);
244 i = -1;
245 }
246
247 if (i <= 0) {
248 rb->left = left;
249 if (s->mode & SSL_MODE_RELEASE_BUFFERS &&
250 SSL_version(s) != DTLS1_VERSION
251 && 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 /*
258 * reads should *never* span multiple packets for DTLS because the
259 * underlying transport protocol is message oriented as opposed to
260 * byte oriented as in the TLS case.
261 */
262 if (SSL_version(s) == DTLS1_VERSION
263 || SSL_version(s) == DTLS1_BAD_VER) {
264 if (n > left)
265 n = left; /* makes the while condition false */
266 }
267 }
268
269 /* done reading, now the book-keeping */
270 rb->offset += n;
271 rb->left = left - n;
272 s->packet_length += n;
273 s->rwstate = SSL_NOTHING;
274 return (n);
275 }
276
277 /*
278 * MAX_EMPTY_RECORDS defines the number of consecutive, empty records that
279 * will be processed per call to ssl3_get_record. Without this limit an
280 * attacker could send empty records at a faster rate than we can process and
281 * cause ssl3_get_record to loop forever.
282 */
283 #define MAX_EMPTY_RECORDS 32
284
285 /*-
286 * Call this to get a new input record.
287 * It will return <= 0 if more data is needed, normally due to an error
288 * or non-blocking IO.
289 * When it finishes, one packet has been decoded and can be found in
290 * ssl->s3->rrec.type - is the type of record
291 * ssl->s3->rrec.data, - data
292 * ssl->s3->rrec.length, - number of bytes
293 */
294 /* used only by ssl3_read_bytes */
ssl3_get_record(SSL * s)295 static int ssl3_get_record(SSL *s)
296 {
297 int ssl_major, ssl_minor, al;
298 int enc_err, n, i, ret = -1;
299 SSL3_RECORD *rr;
300 SSL_SESSION *sess;
301 unsigned char *p;
302 unsigned char md[EVP_MAX_MD_SIZE];
303 short version;
304 unsigned mac_size, orig_len;
305 size_t extra;
306 unsigned empty_record_count = 0;
307
308 rr = &(s->s3->rrec);
309 sess = s->session;
310
311 if (s->options & SSL_OP_MICROSOFT_BIG_SSLV3_BUFFER)
312 extra = SSL3_RT_MAX_EXTRA;
313 else
314 extra = 0;
315 if (extra && !s->s3->init_extra) {
316 /*
317 * An application error: SLS_OP_MICROSOFT_BIG_SSLV3_BUFFER set after
318 * ssl3_setup_buffers() was done
319 */
320 SSLerr(SSL_F_SSL3_GET_RECORD, ERR_R_INTERNAL_ERROR);
321 return -1;
322 }
323
324 again:
325 /* check if we have the header */
326 if ((s->rstate != SSL_ST_READ_BODY) ||
327 (s->packet_length < SSL3_RT_HEADER_LENGTH)) {
328 n = ssl3_read_n(s, SSL3_RT_HEADER_LENGTH, s->s3->rbuf.len, 0);
329 if (n <= 0)
330 return (n); /* error or non-blocking */
331 s->rstate = SSL_ST_READ_BODY;
332
333 p = s->packet;
334
335 /* Pull apart the header into the SSL3_RECORD */
336 rr->type = *(p++);
337 ssl_major = *(p++);
338 ssl_minor = *(p++);
339 version = (ssl_major << 8) | ssl_minor;
340 n2s(p, rr->length);
341 #if 0
342 fprintf(stderr, "Record type=%d, Length=%d\n", rr->type, rr->length);
343 #endif
344
345 /* Lets check version */
346 if (!s->first_packet) {
347 if (version != s->version) {
348 SSLerr(SSL_F_SSL3_GET_RECORD, SSL_R_WRONG_VERSION_NUMBER);
349 if ((s->version & 0xFF00) == (version & 0xFF00)
350 && !s->enc_write_ctx && !s->write_hash) {
351 if (rr->type == SSL3_RT_ALERT) {
352 /*
353 * The record is using an incorrect version number, but
354 * what we've got appears to be an alert. We haven't
355 * read the body yet to check whether its a fatal or
356 * not - but chances are it is. We probably shouldn't
357 * send a fatal alert back. We'll just end.
358 */
359 goto err;
360 }
361 /*
362 * Send back error using their minor version number :-)
363 */
364 s->version = (unsigned short)version;
365 }
366 al = SSL_AD_PROTOCOL_VERSION;
367 goto f_err;
368 }
369 }
370
371 if ((version >> 8) != SSL3_VERSION_MAJOR) {
372 SSLerr(SSL_F_SSL3_GET_RECORD, SSL_R_WRONG_VERSION_NUMBER);
373 goto err;
374 }
375
376 if (rr->length > s->s3->rbuf.len - SSL3_RT_HEADER_LENGTH) {
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 /* now s->packet_length == SSL3_RT_HEADER_LENGTH */
389 i = rr->length;
390 n = ssl3_read_n(s, i, i, 1);
391 if (n <= 0)
392 return (n); /* error or non-blocking io */
393 /*
394 * now n == rr->length, and s->packet_length == SSL3_RT_HEADER_LENGTH
395 * + rr->length
396 */
397 }
398
399 s->rstate = SSL_ST_READ_HEADER; /* set state for later operations */
400
401 /*
402 * At this point, s->packet_length == SSL3_RT_HEADER_LNGTH + rr->length,
403 * and we have that many bytes in s->packet
404 */
405 rr->input = &(s->packet[SSL3_RT_HEADER_LENGTH]);
406
407 /*
408 * ok, we can now read from 's->packet' data into 'rr' rr->input points
409 * at rr->length bytes, which need to be copied into rr->data by either
410 * the decryption or by the decompression When the data is 'copied' into
411 * the rr->data buffer, rr->input will be pointed at the new buffer
412 */
413
414 /*
415 * We now have - encrypted [ MAC [ compressed [ plain ] ] ] rr->length
416 * bytes of encrypted compressed stuff.
417 */
418
419 /* check is not needed I believe */
420 if (rr->length > SSL3_RT_MAX_ENCRYPTED_LENGTH + extra) {
421 al = SSL_AD_RECORD_OVERFLOW;
422 SSLerr(SSL_F_SSL3_GET_RECORD, SSL_R_ENCRYPTED_LENGTH_TOO_LONG);
423 goto f_err;
424 }
425
426 /* decrypt in place in 'rr->input' */
427 rr->data = rr->input;
428
429 enc_err = s->method->ssl3_enc->enc(s, 0);
430 /*-
431 * enc_err is:
432 * 0: (in non-constant time) if the record is publically invalid.
433 * 1: if the padding is valid
434 * -1: if the padding is invalid
435 */
436 if (enc_err == 0) {
437 al = SSL_AD_DECRYPTION_FAILED;
438 SSLerr(SSL_F_SSL3_GET_RECORD, SSL_R_BLOCK_CIPHER_PAD_IS_WRONG);
439 goto f_err;
440 }
441 #ifdef TLS_DEBUG
442 printf("dec %d\n", rr->length);
443 {
444 unsigned int z;
445 for (z = 0; z < rr->length; z++)
446 printf("%02X%c", rr->data[z], ((z + 1) % 16) ? ' ' : '\n');
447 }
448 printf("\n");
449 #endif
450
451 /* r->length is now the compressed data plus mac */
452 if ((sess != NULL) &&
453 (s->enc_read_ctx != NULL) && (EVP_MD_CTX_md(s->read_hash) != NULL)) {
454 /* s->read_hash != NULL => mac_size != -1 */
455 unsigned char *mac = NULL;
456 unsigned char mac_tmp[EVP_MAX_MD_SIZE];
457 mac_size = EVP_MD_CTX_size(s->read_hash);
458 OPENSSL_assert(mac_size <= EVP_MAX_MD_SIZE);
459
460 /*
461 * kludge: *_cbc_remove_padding passes padding length in rr->type
462 */
463 orig_len = rr->length + ((unsigned int)rr->type >> 8);
464
465 /*
466 * orig_len is the length of the record before any padding was
467 * removed. This is public information, as is the MAC in use,
468 * therefore we can safely process the record in a different amount
469 * of time if it's too short to possibly contain a MAC.
470 */
471 if (orig_len < mac_size ||
472 /* CBC records must have a padding length byte too. */
473 (EVP_CIPHER_CTX_mode(s->enc_read_ctx) == EVP_CIPH_CBC_MODE &&
474 orig_len < mac_size + 1)) {
475 al = SSL_AD_DECODE_ERROR;
476 SSLerr(SSL_F_SSL3_GET_RECORD, SSL_R_LENGTH_TOO_SHORT);
477 goto f_err;
478 }
479
480 if (EVP_CIPHER_CTX_mode(s->enc_read_ctx) == EVP_CIPH_CBC_MODE) {
481 /*
482 * We update the length so that the TLS header bytes can be
483 * constructed correctly but we need to extract the MAC in
484 * constant time from within the record, without leaking the
485 * contents of the padding bytes.
486 */
487 mac = mac_tmp;
488 ssl3_cbc_copy_mac(mac_tmp, rr, mac_size, orig_len);
489 rr->length -= mac_size;
490 } else {
491 /*
492 * In this case there's no padding, so |orig_len| equals
493 * |rec->length| and we checked that there's enough bytes for
494 * |mac_size| above.
495 */
496 rr->length -= mac_size;
497 mac = &rr->data[rr->length];
498 }
499
500 i = s->method->ssl3_enc->mac(s, md, 0 /* not send */ );
501 if (i < 0 || mac == NULL
502 || CRYPTO_memcmp(md, mac, (size_t)mac_size) != 0)
503 enc_err = -1;
504 if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH + extra + mac_size)
505 enc_err = -1;
506 }
507
508 if (enc_err < 0) {
509 /*
510 * A separate 'decryption_failed' alert was introduced with TLS 1.0,
511 * SSL 3.0 only has 'bad_record_mac'. But unless a decryption
512 * failure is directly visible from the ciphertext anyway, we should
513 * not reveal which kind of error occured -- this might become
514 * visible to an attacker (e.g. via a logfile)
515 */
516 al = SSL_AD_BAD_RECORD_MAC;
517 SSLerr(SSL_F_SSL3_GET_RECORD,
518 SSL_R_DECRYPTION_FAILED_OR_BAD_RECORD_MAC);
519 goto f_err;
520 }
521
522 /* r->length is now just compressed */
523 if (s->expand != NULL) {
524 if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH + extra) {
525 al = SSL_AD_RECORD_OVERFLOW;
526 SSLerr(SSL_F_SSL3_GET_RECORD, SSL_R_COMPRESSED_LENGTH_TOO_LONG);
527 goto f_err;
528 }
529 if (!ssl3_do_uncompress(s)) {
530 al = SSL_AD_DECOMPRESSION_FAILURE;
531 SSLerr(SSL_F_SSL3_GET_RECORD, SSL_R_BAD_DECOMPRESSION);
532 goto f_err;
533 }
534 }
535
536 if (rr->length > SSL3_RT_MAX_PLAIN_LENGTH + extra) {
537 al = SSL_AD_RECORD_OVERFLOW;
538 SSLerr(SSL_F_SSL3_GET_RECORD, SSL_R_DATA_LENGTH_TOO_LONG);
539 goto f_err;
540 }
541
542 rr->off = 0;
543 /*-
544 * So at this point the following is true
545 * ssl->s3->rrec.type is the type of record
546 * ssl->s3->rrec.length == number of bytes in record
547 * ssl->s3->rrec.off == offset to first valid byte
548 * ssl->s3->rrec.data == where to take bytes from, increment
549 * after use :-).
550 */
551
552 /* we have pulled in a full packet so zero things */
553 s->packet_length = 0;
554
555 /* just read a 0 length packet */
556 if (rr->length == 0) {
557 empty_record_count++;
558 if (empty_record_count > MAX_EMPTY_RECORDS) {
559 al = SSL_AD_UNEXPECTED_MESSAGE;
560 SSLerr(SSL_F_SSL3_GET_RECORD, SSL_R_RECORD_TOO_SMALL);
561 goto f_err;
562 }
563 goto again;
564 }
565 #if 0
566 fprintf(stderr, "Ultimate Record type=%d, Length=%d\n", rr->type,
567 rr->length);
568 #endif
569
570 return (1);
571
572 f_err:
573 ssl3_send_alert(s, SSL3_AL_FATAL, al);
574 err:
575 return (ret);
576 }
577
ssl3_do_uncompress(SSL * ssl)578 int ssl3_do_uncompress(SSL *ssl)
579 {
580 #ifndef OPENSSL_NO_COMP
581 int i;
582 SSL3_RECORD *rr;
583
584 rr = &(ssl->s3->rrec);
585 i = COMP_expand_block(ssl->expand, rr->comp,
586 SSL3_RT_MAX_PLAIN_LENGTH, rr->data,
587 (int)rr->length);
588 if (i < 0)
589 return (0);
590 else
591 rr->length = i;
592 rr->data = rr->comp;
593 #endif
594 return (1);
595 }
596
ssl3_do_compress(SSL * ssl)597 int ssl3_do_compress(SSL *ssl)
598 {
599 #ifndef OPENSSL_NO_COMP
600 int i;
601 SSL3_RECORD *wr;
602
603 wr = &(ssl->s3->wrec);
604 i = COMP_compress_block(ssl->compress, wr->data,
605 SSL3_RT_MAX_COMPRESSED_LENGTH,
606 wr->input, (int)wr->length);
607 if (i < 0)
608 return (0);
609 else
610 wr->length = i;
611
612 wr->input = wr->data;
613 #endif
614 return (1);
615 }
616
617 /*
618 * Call this to write data in records of type 'type' It will return <= 0 if
619 * not all data has been sent or non-blocking IO.
620 */
ssl3_write_bytes(SSL * s,int type,const void * buf_,int len)621 int ssl3_write_bytes(SSL *s, int type, const void *buf_, int len)
622 {
623 const unsigned char *buf = buf_;
624 unsigned int n, nw;
625 int i, tot;
626
627 s->rwstate = SSL_NOTHING;
628 OPENSSL_assert(s->s3->wnum <= INT_MAX);
629 tot = s->s3->wnum;
630 s->s3->wnum = 0;
631
632 if (SSL_in_init(s) && !s->in_handshake) {
633 i = s->handshake_func(s);
634 if (i < 0)
635 return (i);
636 if (i == 0) {
637 SSLerr(SSL_F_SSL3_WRITE_BYTES, SSL_R_SSL_HANDSHAKE_FAILURE);
638 return -1;
639 }
640 }
641
642 /*
643 * ensure that if we end up with a smaller value of data to write out
644 * than the the original len from a write which didn't complete for
645 * non-blocking I/O and also somehow ended up avoiding the check for
646 * this in ssl3_write_pending/SSL_R_BAD_WRITE_RETRY as it must never be
647 * possible to end up with (len-tot) as a large number that will then
648 * promptly send beyond the end of the users buffer ... so we trap and
649 * report the error in a way the user will notice
650 */
651 if (len < tot) {
652 SSLerr(SSL_F_SSL3_WRITE_BYTES, SSL_R_BAD_LENGTH);
653 return (-1);
654 }
655
656 n = (len - tot);
657 for (;;) {
658 if (n > s->max_send_fragment)
659 nw = s->max_send_fragment;
660 else
661 nw = n;
662
663 i = do_ssl3_write(s, type, &(buf[tot]), nw, 0);
664 if (i <= 0) {
665 s->s3->wnum = tot;
666 return i;
667 }
668
669 if ((i == (int)n) ||
670 (type == SSL3_RT_APPLICATION_DATA &&
671 (s->mode & SSL_MODE_ENABLE_PARTIAL_WRITE))) {
672 /*
673 * next chunk of data should get another prepended empty fragment
674 * in ciphersuites with known-IV weakness:
675 */
676 s->s3->empty_fragment_done = 0;
677
678 return tot + i;
679 }
680
681 n -= i;
682 tot += i;
683 }
684 }
685
do_ssl3_write(SSL * s,int type,const unsigned char * buf,unsigned int len,int create_empty_fragment)686 static int do_ssl3_write(SSL *s, int type, const unsigned char *buf,
687 unsigned int len, int create_empty_fragment)
688 {
689 unsigned char *p, *plen;
690 int i, mac_size, clear = 0;
691 int prefix_len = 0;
692 int eivlen;
693 long align = 0;
694 SSL3_RECORD *wr;
695 SSL3_BUFFER *wb = &(s->s3->wbuf);
696 SSL_SESSION *sess;
697
698 /*
699 * first check if there is a SSL3_BUFFER still being written out. This
700 * will happen with non blocking IO
701 */
702 if (wb->left != 0)
703 return (ssl3_write_pending(s, type, buf, len));
704
705 /* If we have an alert to send, lets send it */
706 if (s->s3->alert_dispatch) {
707 i = s->method->ssl_dispatch_alert(s);
708 if (i <= 0)
709 return (i);
710 /* if it went, fall through and send more stuff */
711 }
712
713 if (wb->buf == NULL)
714 if (!ssl3_setup_write_buffer(s))
715 return -1;
716
717 if (len == 0 && !create_empty_fragment)
718 return 0;
719
720 wr = &(s->s3->wrec);
721 sess = s->session;
722
723 if ((sess == NULL) ||
724 (s->enc_write_ctx == NULL) ||
725 (EVP_MD_CTX_md(s->write_hash) == NULL)) {
726 #if 1
727 clear = s->enc_write_ctx ? 0 : 1; /* must be AEAD cipher */
728 #else
729 clear = 1;
730 #endif
731 mac_size = 0;
732 } else {
733 mac_size = EVP_MD_CTX_size(s->write_hash);
734 if (mac_size < 0)
735 goto err;
736 }
737
738 /*
739 * 'create_empty_fragment' is true only when this function calls itself
740 */
741 if (!clear && !create_empty_fragment && !s->s3->empty_fragment_done) {
742 /*
743 * countermeasure against known-IV weakness in CBC ciphersuites (see
744 * http://www.openssl.org/~bodo/tls-cbc.txt)
745 */
746
747 if (s->s3->need_empty_fragments && type == SSL3_RT_APPLICATION_DATA) {
748 /*
749 * recursive function call with 'create_empty_fragment' set; this
750 * prepares and buffers the data for an empty fragment (these
751 * 'prefix_len' bytes are sent out later together with the actual
752 * payload)
753 */
754 prefix_len = do_ssl3_write(s, type, buf, 0, 1);
755 if (prefix_len <= 0)
756 goto err;
757
758 if (prefix_len >
759 (SSL3_RT_HEADER_LENGTH + SSL3_RT_SEND_MAX_ENCRYPTED_OVERHEAD))
760 {
761 /* insufficient space */
762 SSLerr(SSL_F_DO_SSL3_WRITE, ERR_R_INTERNAL_ERROR);
763 goto err;
764 }
765 }
766
767 s->s3->empty_fragment_done = 1;
768 }
769
770 if (create_empty_fragment) {
771 #if defined(SSL3_ALIGN_PAYLOAD) && SSL3_ALIGN_PAYLOAD!=0
772 /*
773 * extra fragment would be couple of cipher blocks, which would be
774 * multiple of SSL3_ALIGN_PAYLOAD, so if we want to align the real
775 * payload, then we can just pretent we simply have two headers.
776 */
777 align = (long)wb->buf + 2 * SSL3_RT_HEADER_LENGTH;
778 align = (-align) & (SSL3_ALIGN_PAYLOAD - 1);
779 #endif
780 p = wb->buf + align;
781 wb->offset = align;
782 } else if (prefix_len) {
783 p = wb->buf + wb->offset + prefix_len;
784 } else {
785 #if defined(SSL3_ALIGN_PAYLOAD) && SSL3_ALIGN_PAYLOAD!=0
786 align = (long)wb->buf + SSL3_RT_HEADER_LENGTH;
787 align = (-align) & (SSL3_ALIGN_PAYLOAD - 1);
788 #endif
789 p = wb->buf + align;
790 wb->offset = align;
791 }
792
793 /* write the header */
794
795 *(p++) = type & 0xff;
796 wr->type = type;
797
798 *(p++) = (s->version >> 8);
799 /*
800 * Some servers hang if iniatial client hello is larger than 256 bytes
801 * and record version number > TLS 1.0
802 */
803 if (s->state == SSL3_ST_CW_CLNT_HELLO_B
804 && !s->renegotiate && TLS1_get_version(s) > TLS1_VERSION)
805 *(p++) = 0x1;
806 else
807 *(p++) = s->version & 0xff;
808
809 /* field where we are to write out packet length */
810 plen = p;
811 p += 2;
812 /* Explicit IV length, block ciphers and TLS version 1.1 or later */
813 if (s->enc_write_ctx && s->version >= TLS1_1_VERSION) {
814 int mode = EVP_CIPHER_CTX_mode(s->enc_write_ctx);
815 if (mode == EVP_CIPH_CBC_MODE) {
816 eivlen = EVP_CIPHER_CTX_iv_length(s->enc_write_ctx);
817 if (eivlen <= 1)
818 eivlen = 0;
819 }
820 /* Need explicit part of IV for GCM mode */
821 else if (mode == EVP_CIPH_GCM_MODE)
822 eivlen = EVP_GCM_TLS_EXPLICIT_IV_LEN;
823 else
824 eivlen = 0;
825 } else
826 eivlen = 0;
827
828 /* lets setup the record stuff. */
829 wr->data = p + eivlen;
830 wr->length = (int)len;
831 wr->input = (unsigned char *)buf;
832
833 /*
834 * we now 'read' from wr->input, wr->length bytes into wr->data
835 */
836
837 /* first we compress */
838 if (s->compress != NULL) {
839 if (!ssl3_do_compress(s)) {
840 SSLerr(SSL_F_DO_SSL3_WRITE, SSL_R_COMPRESSION_FAILURE);
841 goto err;
842 }
843 } else {
844 memcpy(wr->data, wr->input, wr->length);
845 wr->input = wr->data;
846 }
847
848 /*
849 * we should still have the output to wr->data and the input from
850 * wr->input. Length should be wr->length. wr->data still points in the
851 * wb->buf
852 */
853
854 if (mac_size != 0) {
855 if (s->method->ssl3_enc->mac(s, &(p[wr->length + eivlen]), 1) < 0)
856 goto err;
857 wr->length += mac_size;
858 }
859
860 wr->input = p;
861 wr->data = p;
862
863 if (eivlen) {
864 /*
865 * if (RAND_pseudo_bytes(p, eivlen) <= 0) goto err;
866 */
867 wr->length += eivlen;
868 }
869
870 if (s->method->ssl3_enc->enc(s, 1) < 1)
871 goto err;
872
873 /* record length after mac and block padding */
874 s2n(wr->length, plen);
875
876 /*
877 * we should now have wr->data pointing to the encrypted data, which is
878 * wr->length long
879 */
880 wr->type = type; /* not needed but helps for debugging */
881 wr->length += SSL3_RT_HEADER_LENGTH;
882
883 if (create_empty_fragment) {
884 /*
885 * we are in a recursive call; just return the length, don't write
886 * out anything here
887 */
888 return wr->length;
889 }
890
891 /* now let's set up wb */
892 wb->left = prefix_len + wr->length;
893
894 /*
895 * memorize arguments so that ssl3_write_pending can detect bad write
896 * retries later
897 */
898 s->s3->wpend_tot = len;
899 s->s3->wpend_buf = buf;
900 s->s3->wpend_type = type;
901 s->s3->wpend_ret = len;
902
903 /* we now just need to write the buffer */
904 return ssl3_write_pending(s, type, buf, len);
905 err:
906 return -1;
907 }
908
909 /* 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)910 int ssl3_write_pending(SSL *s, int type, const unsigned char *buf,
911 unsigned int len)
912 {
913 int i;
914 SSL3_BUFFER *wb = &(s->s3->wbuf);
915
916 /* XXXX */
917 if ((s->s3->wpend_tot > (int)len)
918 || ((s->s3->wpend_buf != buf) &&
919 !(s->mode & SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER))
920 || (s->s3->wpend_type != type)) {
921 SSLerr(SSL_F_SSL3_WRITE_PENDING, SSL_R_BAD_WRITE_RETRY);
922 return (-1);
923 }
924
925 for (;;) {
926 clear_sys_error();
927 if (s->wbio != NULL) {
928 s->rwstate = SSL_WRITING;
929 i = BIO_write(s->wbio,
930 (char *)&(wb->buf[wb->offset]),
931 (unsigned int)wb->left);
932 } else {
933 SSLerr(SSL_F_SSL3_WRITE_PENDING, SSL_R_BIO_NOT_SET);
934 i = -1;
935 }
936 if (i == wb->left) {
937 wb->left = 0;
938 wb->offset += i;
939 if (s->mode & SSL_MODE_RELEASE_BUFFERS &&
940 SSL_version(s) != DTLS1_VERSION
941 && SSL_version(s) != DTLS1_BAD_VER)
942 ssl3_release_write_buffer(s);
943 s->rwstate = SSL_NOTHING;
944 return (s->s3->wpend_ret);
945 } else if (i <= 0) {
946 if (s->version == DTLS1_VERSION || s->version == DTLS1_BAD_VER) {
947 /*
948 * For DTLS, just drop it. That's kind of the whole point in
949 * using a datagram service
950 */
951 wb->left = 0;
952 }
953 return (i);
954 }
955 wb->offset += i;
956 wb->left -= i;
957 }
958 }
959
960 /*-
961 * Return up to 'len' payload bytes received in 'type' records.
962 * 'type' is one of the following:
963 *
964 * - SSL3_RT_HANDSHAKE (when ssl3_get_message calls us)
965 * - SSL3_RT_APPLICATION_DATA (when ssl3_read calls us)
966 * - 0 (during a shutdown, no data has to be returned)
967 *
968 * If we don't have stored data to work from, read a SSL/TLS record first
969 * (possibly multiple records if we still don't have anything to return).
970 *
971 * This function must handle any surprises the peer may have for us, such as
972 * Alert records (e.g. close_notify), ChangeCipherSpec records (not really
973 * a surprise, but handled as if it were), or renegotiation requests.
974 * Also if record payloads contain fragments too small to process, we store
975 * them until there is enough for the respective protocol (the record protocol
976 * may use arbitrary fragmentation and even interleaving):
977 * Change cipher spec protocol
978 * just 1 byte needed, no need for keeping anything stored
979 * Alert protocol
980 * 2 bytes needed (AlertLevel, AlertDescription)
981 * Handshake protocol
982 * 4 bytes needed (HandshakeType, uint24 length) -- we just have
983 * to detect unexpected Client Hello and Hello Request messages
984 * here, anything else is handled by higher layers
985 * Application data protocol
986 * none of our business
987 */
ssl3_read_bytes(SSL * s,int type,unsigned char * buf,int len,int peek)988 int ssl3_read_bytes(SSL *s, int type, unsigned char *buf, int len, int peek)
989 {
990 int al, i, j, ret;
991 unsigned int n;
992 SSL3_RECORD *rr;
993 void (*cb) (const SSL *ssl, int type2, int val) = NULL;
994
995 if (s->s3->rbuf.buf == NULL) /* Not initialized yet */
996 if (!ssl3_setup_read_buffer(s))
997 return (-1);
998
999 if ((type && (type != SSL3_RT_APPLICATION_DATA)
1000 && (type != SSL3_RT_HANDSHAKE)) || (peek
1001 && (type !=
1002 SSL3_RT_APPLICATION_DATA))) {
1003 SSLerr(SSL_F_SSL3_READ_BYTES, ERR_R_INTERNAL_ERROR);
1004 return -1;
1005 }
1006
1007 if ((type == SSL3_RT_HANDSHAKE) && (s->s3->handshake_fragment_len > 0))
1008 /* (partially) satisfy request from storage */
1009 {
1010 unsigned char *src = s->s3->handshake_fragment;
1011 unsigned char *dst = buf;
1012 unsigned int k;
1013
1014 /* peek == 0 */
1015 n = 0;
1016 while ((len > 0) && (s->s3->handshake_fragment_len > 0)) {
1017 *dst++ = *src++;
1018 len--;
1019 s->s3->handshake_fragment_len--;
1020 n++;
1021 }
1022 /* move any remaining fragment bytes: */
1023 for (k = 0; k < s->s3->handshake_fragment_len; k++)
1024 s->s3->handshake_fragment[k] = *src++;
1025 return n;
1026 }
1027
1028 /*
1029 * Now s->s3->handshake_fragment_len == 0 if type == SSL3_RT_HANDSHAKE.
1030 */
1031
1032 if (!s->in_handshake && SSL_in_init(s)) {
1033 /* type == SSL3_RT_APPLICATION_DATA */
1034 i = s->handshake_func(s);
1035 if (i < 0)
1036 return (i);
1037 if (i == 0) {
1038 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_R_SSL_HANDSHAKE_FAILURE);
1039 return (-1);
1040 }
1041 }
1042 start:
1043 s->rwstate = SSL_NOTHING;
1044
1045 /*-
1046 * s->s3->rrec.type - is the type of record
1047 * s->s3->rrec.data, - data
1048 * s->s3->rrec.off, - offset into 'data' for next read
1049 * s->s3->rrec.length, - number of bytes.
1050 */
1051 rr = &(s->s3->rrec);
1052
1053 /* get new packet if necessary */
1054 if ((rr->length == 0) || (s->rstate == SSL_ST_READ_BODY)) {
1055 ret = ssl3_get_record(s);
1056 if (ret <= 0)
1057 return (ret);
1058 }
1059
1060 /*
1061 * Reset the count of consecutive warning alerts if we've got a non-empty
1062 * record that isn't an alert.
1063 */
1064 if (rr->type != SSL3_RT_ALERT && rr->length != 0)
1065 s->s3->alert_count = 0;
1066
1067 /* we now have a packet which can be read and processed */
1068
1069 if (s->s3->change_cipher_spec /* set when we receive ChangeCipherSpec,
1070 * reset by ssl3_get_finished */
1071 && (rr->type != SSL3_RT_HANDSHAKE)) {
1072 al = SSL_AD_UNEXPECTED_MESSAGE;
1073 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_R_DATA_BETWEEN_CCS_AND_FINISHED);
1074 goto f_err;
1075 }
1076
1077 /*
1078 * If the other end has shut down, throw anything we read away (even in
1079 * 'peek' mode)
1080 */
1081 if (s->shutdown & SSL_RECEIVED_SHUTDOWN) {
1082 rr->length = 0;
1083 s->rwstate = SSL_NOTHING;
1084 return (0);
1085 }
1086
1087 if (type == rr->type) { /* SSL3_RT_APPLICATION_DATA or
1088 * SSL3_RT_HANDSHAKE */
1089 /*
1090 * make sure that we are not getting application data when we are
1091 * doing a handshake for the first time
1092 */
1093 if (SSL_in_init(s) && (type == SSL3_RT_APPLICATION_DATA) &&
1094 (s->enc_read_ctx == NULL)) {
1095 al = SSL_AD_UNEXPECTED_MESSAGE;
1096 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_R_APP_DATA_IN_HANDSHAKE);
1097 goto f_err;
1098 }
1099
1100 if (len <= 0)
1101 return (len);
1102
1103 if ((unsigned int)len > rr->length)
1104 n = rr->length;
1105 else
1106 n = (unsigned int)len;
1107
1108 memcpy(buf, &(rr->data[rr->off]), n);
1109 if (!peek) {
1110 rr->length -= n;
1111 rr->off += n;
1112 if (rr->length == 0) {
1113 s->rstate = SSL_ST_READ_HEADER;
1114 rr->off = 0;
1115 if (s->mode & SSL_MODE_RELEASE_BUFFERS
1116 && s->s3->rbuf.left == 0)
1117 ssl3_release_read_buffer(s);
1118 }
1119 }
1120 return (n);
1121 }
1122
1123 /*
1124 * If we get here, then type != rr->type; if we have a handshake message,
1125 * then it was unexpected (Hello Request or Client Hello).
1126 */
1127
1128 /*
1129 * In case of record types for which we have 'fragment' storage, fill
1130 * that so that we can process the data at a fixed place.
1131 */
1132 {
1133 unsigned int dest_maxlen = 0;
1134 unsigned char *dest = NULL;
1135 unsigned int *dest_len = NULL;
1136
1137 if (rr->type == SSL3_RT_HANDSHAKE) {
1138 dest_maxlen = sizeof s->s3->handshake_fragment;
1139 dest = s->s3->handshake_fragment;
1140 dest_len = &s->s3->handshake_fragment_len;
1141 } else if (rr->type == SSL3_RT_ALERT) {
1142 dest_maxlen = sizeof s->s3->alert_fragment;
1143 dest = s->s3->alert_fragment;
1144 dest_len = &s->s3->alert_fragment_len;
1145 }
1146 #ifndef OPENSSL_NO_HEARTBEATS
1147 else if (rr->type == TLS1_RT_HEARTBEAT) {
1148 tls1_process_heartbeat(s);
1149
1150 /* Exit and notify application to read again */
1151 rr->length = 0;
1152 s->rwstate = SSL_READING;
1153 BIO_clear_retry_flags(SSL_get_rbio(s));
1154 BIO_set_retry_read(SSL_get_rbio(s));
1155 return (-1);
1156 }
1157 #endif
1158
1159 if (dest_maxlen > 0) {
1160 n = dest_maxlen - *dest_len; /* available space in 'dest' */
1161 if (rr->length < n)
1162 n = rr->length; /* available bytes */
1163
1164 /* now move 'n' bytes: */
1165 while (n-- > 0) {
1166 dest[(*dest_len)++] = rr->data[rr->off++];
1167 rr->length--;
1168 }
1169
1170 if (*dest_len < dest_maxlen)
1171 goto start; /* fragment was too small */
1172 }
1173 }
1174
1175 /*-
1176 * s->s3->handshake_fragment_len == 4 iff rr->type == SSL3_RT_HANDSHAKE;
1177 * s->s3->alert_fragment_len == 2 iff rr->type == SSL3_RT_ALERT.
1178 * (Possibly rr is 'empty' now, i.e. rr->length may be 0.)
1179 */
1180
1181 /* If we are a client, check for an incoming 'Hello Request': */
1182 if ((!s->server) &&
1183 (s->s3->handshake_fragment_len >= 4) &&
1184 (s->s3->handshake_fragment[0] == SSL3_MT_HELLO_REQUEST) &&
1185 (s->session != NULL) && (s->session->cipher != NULL)) {
1186 s->s3->handshake_fragment_len = 0;
1187
1188 if ((s->s3->handshake_fragment[1] != 0) ||
1189 (s->s3->handshake_fragment[2] != 0) ||
1190 (s->s3->handshake_fragment[3] != 0)) {
1191 al = SSL_AD_DECODE_ERROR;
1192 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_R_BAD_HELLO_REQUEST);
1193 goto f_err;
1194 }
1195
1196 if (s->msg_callback)
1197 s->msg_callback(0, s->version, SSL3_RT_HANDSHAKE,
1198 s->s3->handshake_fragment, 4, s,
1199 s->msg_callback_arg);
1200
1201 if (SSL_is_init_finished(s) &&
1202 !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS) &&
1203 !s->s3->renegotiate) {
1204 ssl3_renegotiate(s);
1205 if (ssl3_renegotiate_check(s)) {
1206 i = s->handshake_func(s);
1207 if (i < 0)
1208 return (i);
1209 if (i == 0) {
1210 SSLerr(SSL_F_SSL3_READ_BYTES,
1211 SSL_R_SSL_HANDSHAKE_FAILURE);
1212 return (-1);
1213 }
1214
1215 if (!(s->mode & SSL_MODE_AUTO_RETRY)) {
1216 if (s->s3->rbuf.left == 0) { /* no read-ahead left? */
1217 BIO *bio;
1218 /*
1219 * In the case where we try to read application data,
1220 * but we trigger an SSL handshake, we return -1 with
1221 * the retry option set. Otherwise renegotiation may
1222 * cause nasty problems in the blocking world
1223 */
1224 s->rwstate = SSL_READING;
1225 bio = SSL_get_rbio(s);
1226 BIO_clear_retry_flags(bio);
1227 BIO_set_retry_read(bio);
1228 return (-1);
1229 }
1230 }
1231 }
1232 }
1233 /*
1234 * we either finished a handshake or ignored the request, now try
1235 * again to obtain the (application) data we were asked for
1236 */
1237 goto start;
1238 }
1239 /*
1240 * If we are a server and get a client hello when renegotiation isn't
1241 * allowed send back a no renegotiation alert and carry on. WARNING:
1242 * experimental code, needs reviewing (steve)
1243 */
1244 if (s->server &&
1245 SSL_is_init_finished(s) &&
1246 !s->s3->send_connection_binding &&
1247 (s->version > SSL3_VERSION) &&
1248 (s->s3->handshake_fragment_len >= 4) &&
1249 (s->s3->handshake_fragment[0] == SSL3_MT_CLIENT_HELLO) &&
1250 (s->session != NULL) && (s->session->cipher != NULL) &&
1251 !(s->ctx->options & SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION)) {
1252 /*
1253 * s->s3->handshake_fragment_len = 0;
1254 */
1255 rr->length = 0;
1256 ssl3_send_alert(s, SSL3_AL_WARNING, SSL_AD_NO_RENEGOTIATION);
1257 goto start;
1258 }
1259 if (s->s3->alert_fragment_len >= 2) {
1260 int alert_level = s->s3->alert_fragment[0];
1261 int alert_descr = s->s3->alert_fragment[1];
1262
1263 s->s3->alert_fragment_len = 0;
1264
1265 if (s->msg_callback)
1266 s->msg_callback(0, s->version, SSL3_RT_ALERT,
1267 s->s3->alert_fragment, 2, s, s->msg_callback_arg);
1268
1269 if (s->info_callback != NULL)
1270 cb = s->info_callback;
1271 else if (s->ctx->info_callback != NULL)
1272 cb = s->ctx->info_callback;
1273
1274 if (cb != NULL) {
1275 j = (alert_level << 8) | alert_descr;
1276 cb(s, SSL_CB_READ_ALERT, j);
1277 }
1278
1279 if (alert_level == SSL3_AL_WARNING) {
1280 s->s3->warn_alert = alert_descr;
1281
1282 s->s3->alert_count++;
1283 if (s->s3->alert_count == MAX_WARN_ALERT_COUNT) {
1284 al = SSL_AD_UNEXPECTED_MESSAGE;
1285 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_R_TOO_MANY_WARN_ALERTS);
1286 goto f_err;
1287 }
1288
1289 if (alert_descr == SSL_AD_CLOSE_NOTIFY) {
1290 s->shutdown |= SSL_RECEIVED_SHUTDOWN;
1291 return (0);
1292 }
1293 /*
1294 * This is a warning but we receive it if we requested
1295 * renegotiation and the peer denied it. Terminate with a fatal
1296 * alert because if application tried to renegotiatie it
1297 * presumably had a good reason and expects it to succeed. In
1298 * future we might have a renegotiation where we don't care if
1299 * the peer refused it where we carry on.
1300 */
1301 else if (alert_descr == SSL_AD_NO_RENEGOTIATION) {
1302 al = SSL_AD_HANDSHAKE_FAILURE;
1303 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_R_NO_RENEGOTIATION);
1304 goto f_err;
1305 }
1306 #ifdef SSL_AD_MISSING_SRP_USERNAME
1307 else if (alert_descr == SSL_AD_MISSING_SRP_USERNAME)
1308 return (0);
1309 #endif
1310 } else if (alert_level == SSL3_AL_FATAL) {
1311 char tmp[16];
1312
1313 s->rwstate = SSL_NOTHING;
1314 s->s3->fatal_alert = alert_descr;
1315 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_AD_REASON_OFFSET + alert_descr);
1316 BIO_snprintf(tmp, sizeof tmp, "%d", alert_descr);
1317 ERR_add_error_data(2, "SSL alert number ", tmp);
1318 s->shutdown |= SSL_RECEIVED_SHUTDOWN;
1319 SSL_CTX_remove_session(s->ctx, s->session);
1320 return (0);
1321 } else {
1322 al = SSL_AD_ILLEGAL_PARAMETER;
1323 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_R_UNKNOWN_ALERT_TYPE);
1324 goto f_err;
1325 }
1326
1327 goto start;
1328 }
1329
1330 if (s->shutdown & SSL_SENT_SHUTDOWN) { /* but we have not received a
1331 * shutdown */
1332 s->rwstate = SSL_NOTHING;
1333 rr->length = 0;
1334 return (0);
1335 }
1336
1337 if (rr->type == SSL3_RT_CHANGE_CIPHER_SPEC) {
1338 /*
1339 * 'Change Cipher Spec' is just a single byte, so we know exactly
1340 * what the record payload has to look like
1341 */
1342 if ((rr->length != 1) || (rr->off != 0) ||
1343 (rr->data[0] != SSL3_MT_CCS)) {
1344 al = SSL_AD_ILLEGAL_PARAMETER;
1345 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_R_BAD_CHANGE_CIPHER_SPEC);
1346 goto f_err;
1347 }
1348
1349 /* Check we have a cipher to change to */
1350 if (s->s3->tmp.new_cipher == NULL) {
1351 al = SSL_AD_UNEXPECTED_MESSAGE;
1352 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_R_CCS_RECEIVED_EARLY);
1353 goto f_err;
1354 }
1355
1356 if (!(s->s3->flags & SSL3_FLAGS_CCS_OK)) {
1357 al = SSL_AD_UNEXPECTED_MESSAGE;
1358 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_R_CCS_RECEIVED_EARLY);
1359 goto f_err;
1360 }
1361
1362 s->s3->flags &= ~SSL3_FLAGS_CCS_OK;
1363
1364 rr->length = 0;
1365
1366 if (s->msg_callback)
1367 s->msg_callback(0, s->version, SSL3_RT_CHANGE_CIPHER_SPEC,
1368 rr->data, 1, s, s->msg_callback_arg);
1369
1370 s->s3->change_cipher_spec = 1;
1371 if (!ssl3_do_change_cipher_spec(s))
1372 goto err;
1373 else
1374 goto start;
1375 }
1376
1377 /*
1378 * Unexpected handshake message (Client Hello, or protocol violation)
1379 */
1380 if ((s->s3->handshake_fragment_len >= 4) && !s->in_handshake) {
1381 if (((s->state & SSL_ST_MASK) == SSL_ST_OK) &&
1382 !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS)) {
1383 #if 0 /* worked only because C operator preferences
1384 * are not as expected (and because this is
1385 * not really needed for clients except for
1386 * detecting protocol violations): */
1387 s->state = SSL_ST_BEFORE | (s->server)
1388 ? SSL_ST_ACCEPT : SSL_ST_CONNECT;
1389 #else
1390 s->state = s->server ? SSL_ST_ACCEPT : SSL_ST_CONNECT;
1391 #endif
1392 s->renegotiate = 1;
1393 s->new_session = 1;
1394 }
1395 i = s->handshake_func(s);
1396 if (i < 0)
1397 return (i);
1398 if (i == 0) {
1399 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_R_SSL_HANDSHAKE_FAILURE);
1400 return (-1);
1401 }
1402
1403 if (!(s->mode & SSL_MODE_AUTO_RETRY)) {
1404 if (s->s3->rbuf.left == 0) { /* no read-ahead left? */
1405 BIO *bio;
1406 /*
1407 * In the case where we try to read application data, but we
1408 * trigger an SSL handshake, we return -1 with the retry
1409 * option set. Otherwise renegotiation may cause nasty
1410 * problems in the blocking world
1411 */
1412 s->rwstate = SSL_READING;
1413 bio = SSL_get_rbio(s);
1414 BIO_clear_retry_flags(bio);
1415 BIO_set_retry_read(bio);
1416 return (-1);
1417 }
1418 }
1419 goto start;
1420 }
1421
1422 switch (rr->type) {
1423 default:
1424 #ifndef OPENSSL_NO_TLS
1425 /*
1426 * TLS up to v1.1 just ignores unknown message types: TLS v1.2 give
1427 * an unexpected message alert.
1428 */
1429 if (s->version >= TLS1_VERSION && s->version <= TLS1_1_VERSION) {
1430 rr->length = 0;
1431 goto start;
1432 }
1433 #endif
1434 al = SSL_AD_UNEXPECTED_MESSAGE;
1435 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_R_UNEXPECTED_RECORD);
1436 goto f_err;
1437 case SSL3_RT_CHANGE_CIPHER_SPEC:
1438 case SSL3_RT_ALERT:
1439 case SSL3_RT_HANDSHAKE:
1440 /*
1441 * we already handled all of these, with the possible exception of
1442 * SSL3_RT_HANDSHAKE when s->in_handshake is set, but that should not
1443 * happen when type != rr->type
1444 */
1445 al = SSL_AD_UNEXPECTED_MESSAGE;
1446 SSLerr(SSL_F_SSL3_READ_BYTES, ERR_R_INTERNAL_ERROR);
1447 goto f_err;
1448 case SSL3_RT_APPLICATION_DATA:
1449 /*
1450 * At this point, we were expecting handshake data, but have
1451 * application data. If the library was running inside ssl3_read()
1452 * (i.e. in_read_app_data is set) and it makes sense to read
1453 * application data at this point (session renegotiation not yet
1454 * started), we will indulge it.
1455 */
1456 if (s->s3->in_read_app_data &&
1457 (s->s3->total_renegotiations != 0) &&
1458 (((s->state & SSL_ST_CONNECT) &&
1459 (s->state >= SSL3_ST_CW_CLNT_HELLO_A) &&
1460 (s->state <= SSL3_ST_CR_SRVR_HELLO_A)
1461 ) || ((s->state & SSL_ST_ACCEPT) &&
1462 (s->state <= SSL3_ST_SW_HELLO_REQ_A) &&
1463 (s->state >= SSL3_ST_SR_CLNT_HELLO_A)
1464 )
1465 )) {
1466 s->s3->in_read_app_data = 2;
1467 return (-1);
1468 } else {
1469 al = SSL_AD_UNEXPECTED_MESSAGE;
1470 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_R_UNEXPECTED_RECORD);
1471 goto f_err;
1472 }
1473 }
1474 /* not reached */
1475
1476 f_err:
1477 ssl3_send_alert(s, SSL3_AL_FATAL, al);
1478 err:
1479 return (-1);
1480 }
1481
ssl3_do_change_cipher_spec(SSL * s)1482 int ssl3_do_change_cipher_spec(SSL *s)
1483 {
1484 int i;
1485 const char *sender;
1486 int slen;
1487
1488 if (s->state & SSL_ST_ACCEPT)
1489 i = SSL3_CHANGE_CIPHER_SERVER_READ;
1490 else
1491 i = SSL3_CHANGE_CIPHER_CLIENT_READ;
1492
1493 if (s->s3->tmp.key_block == NULL) {
1494 if (s->session == NULL || s->session->master_key_length == 0) {
1495 /* might happen if dtls1_read_bytes() calls this */
1496 SSLerr(SSL_F_SSL3_DO_CHANGE_CIPHER_SPEC,
1497 SSL_R_CCS_RECEIVED_EARLY);
1498 return (0);
1499 }
1500
1501 s->session->cipher = s->s3->tmp.new_cipher;
1502 if (!s->method->ssl3_enc->setup_key_block(s))
1503 return (0);
1504 }
1505
1506 if (!s->method->ssl3_enc->change_cipher_state(s, i))
1507 return (0);
1508
1509 /*
1510 * we have to record the message digest at this point so we can get it
1511 * before we read the finished message
1512 */
1513 if (s->state & SSL_ST_CONNECT) {
1514 sender = s->method->ssl3_enc->server_finished_label;
1515 slen = s->method->ssl3_enc->server_finished_label_len;
1516 } else {
1517 sender = s->method->ssl3_enc->client_finished_label;
1518 slen = s->method->ssl3_enc->client_finished_label_len;
1519 }
1520
1521 i = s->method->ssl3_enc->final_finish_mac(s,
1522 sender, slen,
1523 s->s3->tmp.peer_finish_md);
1524 if (i == 0) {
1525 SSLerr(SSL_F_SSL3_DO_CHANGE_CIPHER_SPEC, ERR_R_INTERNAL_ERROR);
1526 return 0;
1527 }
1528 s->s3->tmp.peer_finish_md_len = i;
1529
1530 return (1);
1531 }
1532
ssl3_send_alert(SSL * s,int level,int desc)1533 int ssl3_send_alert(SSL *s, int level, int desc)
1534 {
1535 /* Map tls/ssl alert value to correct one */
1536 desc = s->method->ssl3_enc->alert_value(desc);
1537 if (s->version == SSL3_VERSION && desc == SSL_AD_PROTOCOL_VERSION)
1538 desc = SSL_AD_HANDSHAKE_FAILURE; /* SSL 3.0 does not have
1539 * protocol_version alerts */
1540 if (desc < 0)
1541 return -1;
1542 /* If a fatal one, remove from cache */
1543 if ((level == 2) && (s->session != NULL))
1544 SSL_CTX_remove_session(s->ctx, s->session);
1545
1546 s->s3->alert_dispatch = 1;
1547 s->s3->send_alert[0] = level;
1548 s->s3->send_alert[1] = desc;
1549 if (s->s3->wbuf.left == 0) /* data still being written out? */
1550 return s->method->ssl_dispatch_alert(s);
1551 /*
1552 * else data is still being written out, we will get written some time in
1553 * the future
1554 */
1555 return -1;
1556 }
1557
ssl3_dispatch_alert(SSL * s)1558 int ssl3_dispatch_alert(SSL *s)
1559 {
1560 int i, j;
1561 void (*cb) (const SSL *ssl, int type, int val) = NULL;
1562
1563 s->s3->alert_dispatch = 0;
1564 i = do_ssl3_write(s, SSL3_RT_ALERT, &s->s3->send_alert[0], 2, 0);
1565 if (i <= 0) {
1566 s->s3->alert_dispatch = 1;
1567 } else {
1568 /*
1569 * Alert sent to BIO. If it is important, flush it now. If the
1570 * message does not get sent due to non-blocking IO, we will not
1571 * worry too much.
1572 */
1573 if (s->s3->send_alert[0] == SSL3_AL_FATAL)
1574 (void)BIO_flush(s->wbio);
1575
1576 if (s->msg_callback)
1577 s->msg_callback(1, s->version, SSL3_RT_ALERT, s->s3->send_alert,
1578 2, s, s->msg_callback_arg);
1579
1580 if (s->info_callback != NULL)
1581 cb = s->info_callback;
1582 else if (s->ctx->info_callback != NULL)
1583 cb = s->ctx->info_callback;
1584
1585 if (cb != NULL) {
1586 j = (s->s3->send_alert[0] << 8) | s->s3->send_alert[1];
1587 cb(s, SSL_CB_WRITE_ALERT, j);
1588 }
1589 }
1590 return (i);
1591 }
1592