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 /* we may have released our buffer, so get it again */
712 if (wb->buf == NULL)
713 if (!ssl3_setup_write_buffer(s))
714 return -1;
715 }
716
717 if (wb->buf == NULL)
718 if (!ssl3_setup_write_buffer(s))
719 return -1;
720
721 if (len == 0 && !create_empty_fragment)
722 return 0;
723
724 wr = &(s->s3->wrec);
725 sess = s->session;
726
727 if ((sess == NULL) ||
728 (s->enc_write_ctx == NULL) ||
729 (EVP_MD_CTX_md(s->write_hash) == NULL)) {
730 #if 1
731 clear = s->enc_write_ctx ? 0 : 1; /* must be AEAD cipher */
732 #else
733 clear = 1;
734 #endif
735 mac_size = 0;
736 } else {
737 mac_size = EVP_MD_CTX_size(s->write_hash);
738 if (mac_size < 0)
739 goto err;
740 }
741
742 /*
743 * 'create_empty_fragment' is true only when this function calls itself
744 */
745 if (!clear && !create_empty_fragment && !s->s3->empty_fragment_done) {
746 /*
747 * countermeasure against known-IV weakness in CBC ciphersuites (see
748 * http://www.openssl.org/~bodo/tls-cbc.txt)
749 */
750
751 if (s->s3->need_empty_fragments && type == SSL3_RT_APPLICATION_DATA) {
752 /*
753 * recursive function call with 'create_empty_fragment' set; this
754 * prepares and buffers the data for an empty fragment (these
755 * 'prefix_len' bytes are sent out later together with the actual
756 * payload)
757 */
758 prefix_len = do_ssl3_write(s, type, buf, 0, 1);
759 if (prefix_len <= 0)
760 goto err;
761
762 if (prefix_len >
763 (SSL3_RT_HEADER_LENGTH + SSL3_RT_SEND_MAX_ENCRYPTED_OVERHEAD))
764 {
765 /* insufficient space */
766 SSLerr(SSL_F_DO_SSL3_WRITE, ERR_R_INTERNAL_ERROR);
767 goto err;
768 }
769 }
770
771 s->s3->empty_fragment_done = 1;
772 }
773
774 if (create_empty_fragment) {
775 #if defined(SSL3_ALIGN_PAYLOAD) && SSL3_ALIGN_PAYLOAD!=0
776 /*
777 * extra fragment would be couple of cipher blocks, which would be
778 * multiple of SSL3_ALIGN_PAYLOAD, so if we want to align the real
779 * payload, then we can just pretent we simply have two headers.
780 */
781 align = (long)wb->buf + 2 * SSL3_RT_HEADER_LENGTH;
782 align = (-align) & (SSL3_ALIGN_PAYLOAD - 1);
783 #endif
784 p = wb->buf + align;
785 wb->offset = align;
786 } else if (prefix_len) {
787 p = wb->buf + wb->offset + prefix_len;
788 } else {
789 #if defined(SSL3_ALIGN_PAYLOAD) && SSL3_ALIGN_PAYLOAD!=0
790 align = (long)wb->buf + SSL3_RT_HEADER_LENGTH;
791 align = (-align) & (SSL3_ALIGN_PAYLOAD - 1);
792 #endif
793 p = wb->buf + align;
794 wb->offset = align;
795 }
796
797 /* write the header */
798
799 *(p++) = type & 0xff;
800 wr->type = type;
801
802 *(p++) = (s->version >> 8);
803 /*
804 * Some servers hang if iniatial client hello is larger than 256 bytes
805 * and record version number > TLS 1.0
806 */
807 if (s->state == SSL3_ST_CW_CLNT_HELLO_B
808 && !s->renegotiate && TLS1_get_version(s) > TLS1_VERSION)
809 *(p++) = 0x1;
810 else
811 *(p++) = s->version & 0xff;
812
813 /* field where we are to write out packet length */
814 plen = p;
815 p += 2;
816 /* Explicit IV length, block ciphers and TLS version 1.1 or later */
817 if (s->enc_write_ctx && s->version >= TLS1_1_VERSION) {
818 int mode = EVP_CIPHER_CTX_mode(s->enc_write_ctx);
819 if (mode == EVP_CIPH_CBC_MODE) {
820 eivlen = EVP_CIPHER_CTX_iv_length(s->enc_write_ctx);
821 if (eivlen <= 1)
822 eivlen = 0;
823 }
824 /* Need explicit part of IV for GCM mode */
825 else if (mode == EVP_CIPH_GCM_MODE)
826 eivlen = EVP_GCM_TLS_EXPLICIT_IV_LEN;
827 else
828 eivlen = 0;
829 } else
830 eivlen = 0;
831
832 /* lets setup the record stuff. */
833 wr->data = p + eivlen;
834 wr->length = (int)len;
835 wr->input = (unsigned char *)buf;
836
837 /*
838 * we now 'read' from wr->input, wr->length bytes into wr->data
839 */
840
841 /* first we compress */
842 if (s->compress != NULL) {
843 if (!ssl3_do_compress(s)) {
844 SSLerr(SSL_F_DO_SSL3_WRITE, SSL_R_COMPRESSION_FAILURE);
845 goto err;
846 }
847 } else {
848 memcpy(wr->data, wr->input, wr->length);
849 wr->input = wr->data;
850 }
851
852 /*
853 * we should still have the output to wr->data and the input from
854 * wr->input. Length should be wr->length. wr->data still points in the
855 * wb->buf
856 */
857
858 if (mac_size != 0) {
859 if (s->method->ssl3_enc->mac(s, &(p[wr->length + eivlen]), 1) < 0)
860 goto err;
861 wr->length += mac_size;
862 }
863
864 wr->input = p;
865 wr->data = p;
866
867 if (eivlen) {
868 /*
869 * if (RAND_pseudo_bytes(p, eivlen) <= 0) goto err;
870 */
871 wr->length += eivlen;
872 }
873
874 if (s->method->ssl3_enc->enc(s, 1) < 1)
875 goto err;
876
877 /* record length after mac and block padding */
878 s2n(wr->length, plen);
879
880 /*
881 * we should now have wr->data pointing to the encrypted data, which is
882 * wr->length long
883 */
884 wr->type = type; /* not needed but helps for debugging */
885 wr->length += SSL3_RT_HEADER_LENGTH;
886
887 if (create_empty_fragment) {
888 /*
889 * we are in a recursive call; just return the length, don't write
890 * out anything here
891 */
892 return wr->length;
893 }
894
895 /* now let's set up wb */
896 wb->left = prefix_len + wr->length;
897
898 /*
899 * memorize arguments so that ssl3_write_pending can detect bad write
900 * retries later
901 */
902 s->s3->wpend_tot = len;
903 s->s3->wpend_buf = buf;
904 s->s3->wpend_type = type;
905 s->s3->wpend_ret = len;
906
907 /* we now just need to write the buffer */
908 return ssl3_write_pending(s, type, buf, len);
909 err:
910 return -1;
911 }
912
913 /* 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)914 int ssl3_write_pending(SSL *s, int type, const unsigned char *buf,
915 unsigned int len)
916 {
917 int i;
918 SSL3_BUFFER *wb = &(s->s3->wbuf);
919
920 /* XXXX */
921 if ((s->s3->wpend_tot > (int)len)
922 || ((s->s3->wpend_buf != buf) &&
923 !(s->mode & SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER))
924 || (s->s3->wpend_type != type)) {
925 SSLerr(SSL_F_SSL3_WRITE_PENDING, SSL_R_BAD_WRITE_RETRY);
926 return (-1);
927 }
928
929 for (;;) {
930 clear_sys_error();
931 if (s->wbio != NULL) {
932 s->rwstate = SSL_WRITING;
933 i = BIO_write(s->wbio,
934 (char *)&(wb->buf[wb->offset]),
935 (unsigned int)wb->left);
936 } else {
937 SSLerr(SSL_F_SSL3_WRITE_PENDING, SSL_R_BIO_NOT_SET);
938 i = -1;
939 }
940 if (i == wb->left) {
941 wb->left = 0;
942 wb->offset += i;
943 if (s->mode & SSL_MODE_RELEASE_BUFFERS &&
944 SSL_version(s) != DTLS1_VERSION
945 && SSL_version(s) != DTLS1_BAD_VER)
946 ssl3_release_write_buffer(s);
947 s->rwstate = SSL_NOTHING;
948 return (s->s3->wpend_ret);
949 } else if (i <= 0) {
950 if (s->version == DTLS1_VERSION || s->version == DTLS1_BAD_VER) {
951 /*
952 * For DTLS, just drop it. That's kind of the whole point in
953 * using a datagram service
954 */
955 wb->left = 0;
956 }
957 return (i);
958 }
959 wb->offset += i;
960 wb->left -= i;
961 }
962 }
963
964 /*-
965 * Return up to 'len' payload bytes received in 'type' records.
966 * 'type' is one of the following:
967 *
968 * - SSL3_RT_HANDSHAKE (when ssl3_get_message calls us)
969 * - SSL3_RT_APPLICATION_DATA (when ssl3_read calls us)
970 * - 0 (during a shutdown, no data has to be returned)
971 *
972 * If we don't have stored data to work from, read a SSL/TLS record first
973 * (possibly multiple records if we still don't have anything to return).
974 *
975 * This function must handle any surprises the peer may have for us, such as
976 * Alert records (e.g. close_notify), ChangeCipherSpec records (not really
977 * a surprise, but handled as if it were), or renegotiation requests.
978 * Also if record payloads contain fragments too small to process, we store
979 * them until there is enough for the respective protocol (the record protocol
980 * may use arbitrary fragmentation and even interleaving):
981 * Change cipher spec protocol
982 * just 1 byte needed, no need for keeping anything stored
983 * Alert protocol
984 * 2 bytes needed (AlertLevel, AlertDescription)
985 * Handshake protocol
986 * 4 bytes needed (HandshakeType, uint24 length) -- we just have
987 * to detect unexpected Client Hello and Hello Request messages
988 * here, anything else is handled by higher layers
989 * Application data protocol
990 * none of our business
991 */
ssl3_read_bytes(SSL * s,int type,unsigned char * buf,int len,int peek)992 int ssl3_read_bytes(SSL *s, int type, unsigned char *buf, int len, int peek)
993 {
994 int al, i, j, ret;
995 unsigned int n;
996 SSL3_RECORD *rr;
997 void (*cb) (const SSL *ssl, int type2, int val) = NULL;
998
999 if (s->s3->rbuf.buf == NULL) /* Not initialized yet */
1000 if (!ssl3_setup_read_buffer(s))
1001 return (-1);
1002
1003 if ((type && (type != SSL3_RT_APPLICATION_DATA)
1004 && (type != SSL3_RT_HANDSHAKE)) || (peek
1005 && (type !=
1006 SSL3_RT_APPLICATION_DATA))) {
1007 SSLerr(SSL_F_SSL3_READ_BYTES, ERR_R_INTERNAL_ERROR);
1008 return -1;
1009 }
1010
1011 if ((type == SSL3_RT_HANDSHAKE) && (s->s3->handshake_fragment_len > 0))
1012 /* (partially) satisfy request from storage */
1013 {
1014 unsigned char *src = s->s3->handshake_fragment;
1015 unsigned char *dst = buf;
1016 unsigned int k;
1017
1018 /* peek == 0 */
1019 n = 0;
1020 while ((len > 0) && (s->s3->handshake_fragment_len > 0)) {
1021 *dst++ = *src++;
1022 len--;
1023 s->s3->handshake_fragment_len--;
1024 n++;
1025 }
1026 /* move any remaining fragment bytes: */
1027 for (k = 0; k < s->s3->handshake_fragment_len; k++)
1028 s->s3->handshake_fragment[k] = *src++;
1029 return n;
1030 }
1031
1032 /*
1033 * Now s->s3->handshake_fragment_len == 0 if type == SSL3_RT_HANDSHAKE.
1034 */
1035
1036 if (!s->in_handshake && SSL_in_init(s)) {
1037 /* type == SSL3_RT_APPLICATION_DATA */
1038 i = s->handshake_func(s);
1039 if (i < 0)
1040 return (i);
1041 if (i == 0) {
1042 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_R_SSL_HANDSHAKE_FAILURE);
1043 return (-1);
1044 }
1045 }
1046 start:
1047 s->rwstate = SSL_NOTHING;
1048
1049 /*-
1050 * s->s3->rrec.type - is the type of record
1051 * s->s3->rrec.data, - data
1052 * s->s3->rrec.off, - offset into 'data' for next read
1053 * s->s3->rrec.length, - number of bytes.
1054 */
1055 rr = &(s->s3->rrec);
1056
1057 /* get new packet if necessary */
1058 if ((rr->length == 0) || (s->rstate == SSL_ST_READ_BODY)) {
1059 ret = ssl3_get_record(s);
1060 if (ret <= 0)
1061 return (ret);
1062 }
1063
1064 /* we now have a packet which can be read and processed */
1065
1066 if (s->s3->change_cipher_spec /* set when we receive ChangeCipherSpec,
1067 * reset by ssl3_get_finished */
1068 && (rr->type != SSL3_RT_HANDSHAKE)) {
1069 al = SSL_AD_UNEXPECTED_MESSAGE;
1070 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_R_DATA_BETWEEN_CCS_AND_FINISHED);
1071 goto f_err;
1072 }
1073
1074 /*
1075 * If the other end has shut down, throw anything we read away (even in
1076 * 'peek' mode)
1077 */
1078 if (s->shutdown & SSL_RECEIVED_SHUTDOWN) {
1079 rr->length = 0;
1080 s->rwstate = SSL_NOTHING;
1081 return (0);
1082 }
1083
1084 if (type == rr->type) { /* SSL3_RT_APPLICATION_DATA or
1085 * SSL3_RT_HANDSHAKE */
1086 /*
1087 * make sure that we are not getting application data when we are
1088 * doing a handshake for the first time
1089 */
1090 if (SSL_in_init(s) && (type == SSL3_RT_APPLICATION_DATA) &&
1091 (s->enc_read_ctx == NULL)) {
1092 al = SSL_AD_UNEXPECTED_MESSAGE;
1093 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_R_APP_DATA_IN_HANDSHAKE);
1094 goto f_err;
1095 }
1096
1097 if (len <= 0)
1098 return (len);
1099
1100 if ((unsigned int)len > rr->length)
1101 n = rr->length;
1102 else
1103 n = (unsigned int)len;
1104
1105 memcpy(buf, &(rr->data[rr->off]), n);
1106 if (!peek) {
1107 rr->length -= n;
1108 rr->off += n;
1109 if (rr->length == 0) {
1110 s->rstate = SSL_ST_READ_HEADER;
1111 rr->off = 0;
1112 if (s->mode & SSL_MODE_RELEASE_BUFFERS
1113 && s->s3->rbuf.left == 0)
1114 ssl3_release_read_buffer(s);
1115 }
1116 }
1117 return (n);
1118 }
1119
1120 /*
1121 * If we get here, then type != rr->type; if we have a handshake message,
1122 * then it was unexpected (Hello Request or Client Hello).
1123 */
1124
1125 /*
1126 * In case of record types for which we have 'fragment' storage, fill
1127 * that so that we can process the data at a fixed place.
1128 */
1129 {
1130 unsigned int dest_maxlen = 0;
1131 unsigned char *dest = NULL;
1132 unsigned int *dest_len = NULL;
1133
1134 if (rr->type == SSL3_RT_HANDSHAKE) {
1135 dest_maxlen = sizeof s->s3->handshake_fragment;
1136 dest = s->s3->handshake_fragment;
1137 dest_len = &s->s3->handshake_fragment_len;
1138 } else if (rr->type == SSL3_RT_ALERT) {
1139 dest_maxlen = sizeof s->s3->alert_fragment;
1140 dest = s->s3->alert_fragment;
1141 dest_len = &s->s3->alert_fragment_len;
1142 }
1143 #ifndef OPENSSL_NO_HEARTBEATS
1144 else if (rr->type == TLS1_RT_HEARTBEAT) {
1145 tls1_process_heartbeat(s);
1146
1147 /* Exit and notify application to read again */
1148 rr->length = 0;
1149 s->rwstate = SSL_READING;
1150 BIO_clear_retry_flags(SSL_get_rbio(s));
1151 BIO_set_retry_read(SSL_get_rbio(s));
1152 return (-1);
1153 }
1154 #endif
1155
1156 if (dest_maxlen > 0) {
1157 n = dest_maxlen - *dest_len; /* available space in 'dest' */
1158 if (rr->length < n)
1159 n = rr->length; /* available bytes */
1160
1161 /* now move 'n' bytes: */
1162 while (n-- > 0) {
1163 dest[(*dest_len)++] = rr->data[rr->off++];
1164 rr->length--;
1165 }
1166
1167 if (*dest_len < dest_maxlen)
1168 goto start; /* fragment was too small */
1169 }
1170 }
1171
1172 /*-
1173 * s->s3->handshake_fragment_len == 4 iff rr->type == SSL3_RT_HANDSHAKE;
1174 * s->s3->alert_fragment_len == 2 iff rr->type == SSL3_RT_ALERT.
1175 * (Possibly rr is 'empty' now, i.e. rr->length may be 0.)
1176 */
1177
1178 /* If we are a client, check for an incoming 'Hello Request': */
1179 if ((!s->server) &&
1180 (s->s3->handshake_fragment_len >= 4) &&
1181 (s->s3->handshake_fragment[0] == SSL3_MT_HELLO_REQUEST) &&
1182 (s->session != NULL) && (s->session->cipher != NULL)) {
1183 s->s3->handshake_fragment_len = 0;
1184
1185 if ((s->s3->handshake_fragment[1] != 0) ||
1186 (s->s3->handshake_fragment[2] != 0) ||
1187 (s->s3->handshake_fragment[3] != 0)) {
1188 al = SSL_AD_DECODE_ERROR;
1189 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_R_BAD_HELLO_REQUEST);
1190 goto f_err;
1191 }
1192
1193 if (s->msg_callback)
1194 s->msg_callback(0, s->version, SSL3_RT_HANDSHAKE,
1195 s->s3->handshake_fragment, 4, s,
1196 s->msg_callback_arg);
1197
1198 if (SSL_is_init_finished(s) &&
1199 !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS) &&
1200 !s->s3->renegotiate) {
1201 ssl3_renegotiate(s);
1202 if (ssl3_renegotiate_check(s)) {
1203 i = s->handshake_func(s);
1204 if (i < 0)
1205 return (i);
1206 if (i == 0) {
1207 SSLerr(SSL_F_SSL3_READ_BYTES,
1208 SSL_R_SSL_HANDSHAKE_FAILURE);
1209 return (-1);
1210 }
1211
1212 if (!(s->mode & SSL_MODE_AUTO_RETRY)) {
1213 if (s->s3->rbuf.left == 0) { /* no read-ahead left? */
1214 BIO *bio;
1215 /*
1216 * In the case where we try to read application data,
1217 * but we trigger an SSL handshake, we return -1 with
1218 * the retry option set. Otherwise renegotiation may
1219 * cause nasty problems in the blocking world
1220 */
1221 s->rwstate = SSL_READING;
1222 bio = SSL_get_rbio(s);
1223 BIO_clear_retry_flags(bio);
1224 BIO_set_retry_read(bio);
1225 return (-1);
1226 }
1227 }
1228 }
1229 }
1230 /*
1231 * we either finished a handshake or ignored the request, now try
1232 * again to obtain the (application) data we were asked for
1233 */
1234 goto start;
1235 }
1236 /*
1237 * If we are a server and get a client hello when renegotiation isn't
1238 * allowed send back a no renegotiation alert and carry on. WARNING:
1239 * experimental code, needs reviewing (steve)
1240 */
1241 if (s->server &&
1242 SSL_is_init_finished(s) &&
1243 !s->s3->send_connection_binding &&
1244 (s->version > SSL3_VERSION) &&
1245 (s->s3->handshake_fragment_len >= 4) &&
1246 (s->s3->handshake_fragment[0] == SSL3_MT_CLIENT_HELLO) &&
1247 (s->session != NULL) && (s->session->cipher != NULL) &&
1248 !(s->ctx->options & SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION)) {
1249 /*
1250 * s->s3->handshake_fragment_len = 0;
1251 */
1252 rr->length = 0;
1253 ssl3_send_alert(s, SSL3_AL_WARNING, SSL_AD_NO_RENEGOTIATION);
1254 goto start;
1255 }
1256 if (s->s3->alert_fragment_len >= 2) {
1257 int alert_level = s->s3->alert_fragment[0];
1258 int alert_descr = s->s3->alert_fragment[1];
1259
1260 s->s3->alert_fragment_len = 0;
1261
1262 if (s->msg_callback)
1263 s->msg_callback(0, s->version, SSL3_RT_ALERT,
1264 s->s3->alert_fragment, 2, s, s->msg_callback_arg);
1265
1266 if (s->info_callback != NULL)
1267 cb = s->info_callback;
1268 else if (s->ctx->info_callback != NULL)
1269 cb = s->ctx->info_callback;
1270
1271 if (cb != NULL) {
1272 j = (alert_level << 8) | alert_descr;
1273 cb(s, SSL_CB_READ_ALERT, j);
1274 }
1275
1276 if (alert_level == SSL3_AL_WARNING) {
1277 s->s3->warn_alert = alert_descr;
1278 if (alert_descr == SSL_AD_CLOSE_NOTIFY) {
1279 s->shutdown |= SSL_RECEIVED_SHUTDOWN;
1280 return (0);
1281 }
1282 /*
1283 * This is a warning but we receive it if we requested
1284 * renegotiation and the peer denied it. Terminate with a fatal
1285 * alert because if application tried to renegotiatie it
1286 * presumably had a good reason and expects it to succeed. In
1287 * future we might have a renegotiation where we don't care if
1288 * the peer refused it where we carry on.
1289 */
1290 else if (alert_descr == SSL_AD_NO_RENEGOTIATION) {
1291 al = SSL_AD_HANDSHAKE_FAILURE;
1292 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_R_NO_RENEGOTIATION);
1293 goto f_err;
1294 }
1295 #ifdef SSL_AD_MISSING_SRP_USERNAME
1296 else if (alert_descr == SSL_AD_MISSING_SRP_USERNAME)
1297 return (0);
1298 #endif
1299 } else if (alert_level == SSL3_AL_FATAL) {
1300 char tmp[16];
1301
1302 s->rwstate = SSL_NOTHING;
1303 s->s3->fatal_alert = alert_descr;
1304 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_AD_REASON_OFFSET + alert_descr);
1305 BIO_snprintf(tmp, sizeof tmp, "%d", alert_descr);
1306 ERR_add_error_data(2, "SSL alert number ", tmp);
1307 s->shutdown |= SSL_RECEIVED_SHUTDOWN;
1308 SSL_CTX_remove_session(s->ctx, s->session);
1309 return (0);
1310 } else {
1311 al = SSL_AD_ILLEGAL_PARAMETER;
1312 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_R_UNKNOWN_ALERT_TYPE);
1313 goto f_err;
1314 }
1315
1316 goto start;
1317 }
1318
1319 if (s->shutdown & SSL_SENT_SHUTDOWN) { /* but we have not received a
1320 * shutdown */
1321 s->rwstate = SSL_NOTHING;
1322 rr->length = 0;
1323 return (0);
1324 }
1325
1326 if (rr->type == SSL3_RT_CHANGE_CIPHER_SPEC) {
1327 /*
1328 * 'Change Cipher Spec' is just a single byte, so we know exactly
1329 * what the record payload has to look like
1330 */
1331 if ((rr->length != 1) || (rr->off != 0) ||
1332 (rr->data[0] != SSL3_MT_CCS)) {
1333 al = SSL_AD_ILLEGAL_PARAMETER;
1334 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_R_BAD_CHANGE_CIPHER_SPEC);
1335 goto f_err;
1336 }
1337
1338 /* Check we have a cipher to change to */
1339 if (s->s3->tmp.new_cipher == NULL) {
1340 al = SSL_AD_UNEXPECTED_MESSAGE;
1341 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_R_CCS_RECEIVED_EARLY);
1342 goto f_err;
1343 }
1344
1345 if (!(s->s3->flags & SSL3_FLAGS_CCS_OK)) {
1346 al = SSL_AD_UNEXPECTED_MESSAGE;
1347 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_R_CCS_RECEIVED_EARLY);
1348 goto f_err;
1349 }
1350
1351 s->s3->flags &= ~SSL3_FLAGS_CCS_OK;
1352
1353 rr->length = 0;
1354
1355 if (s->msg_callback)
1356 s->msg_callback(0, s->version, SSL3_RT_CHANGE_CIPHER_SPEC,
1357 rr->data, 1, s, s->msg_callback_arg);
1358
1359 s->s3->change_cipher_spec = 1;
1360 if (!ssl3_do_change_cipher_spec(s))
1361 goto err;
1362 else
1363 goto start;
1364 }
1365
1366 /*
1367 * Unexpected handshake message (Client Hello, or protocol violation)
1368 */
1369 if ((s->s3->handshake_fragment_len >= 4) && !s->in_handshake) {
1370 if (((s->state & SSL_ST_MASK) == SSL_ST_OK) &&
1371 !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS)) {
1372 #if 0 /* worked only because C operator preferences
1373 * are not as expected (and because this is
1374 * not really needed for clients except for
1375 * detecting protocol violations): */
1376 s->state = SSL_ST_BEFORE | (s->server)
1377 ? SSL_ST_ACCEPT : SSL_ST_CONNECT;
1378 #else
1379 s->state = s->server ? SSL_ST_ACCEPT : SSL_ST_CONNECT;
1380 #endif
1381 s->renegotiate = 1;
1382 s->new_session = 1;
1383 }
1384 i = s->handshake_func(s);
1385 if (i < 0)
1386 return (i);
1387 if (i == 0) {
1388 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_R_SSL_HANDSHAKE_FAILURE);
1389 return (-1);
1390 }
1391
1392 if (!(s->mode & SSL_MODE_AUTO_RETRY)) {
1393 if (s->s3->rbuf.left == 0) { /* no read-ahead left? */
1394 BIO *bio;
1395 /*
1396 * In the case where we try to read application data, but we
1397 * trigger an SSL handshake, we return -1 with the retry
1398 * option set. Otherwise renegotiation may cause nasty
1399 * problems in the blocking world
1400 */
1401 s->rwstate = SSL_READING;
1402 bio = SSL_get_rbio(s);
1403 BIO_clear_retry_flags(bio);
1404 BIO_set_retry_read(bio);
1405 return (-1);
1406 }
1407 }
1408 goto start;
1409 }
1410
1411 switch (rr->type) {
1412 default:
1413 #ifndef OPENSSL_NO_TLS
1414 /*
1415 * TLS up to v1.1 just ignores unknown message types: TLS v1.2 give
1416 * an unexpected message alert.
1417 */
1418 if (s->version >= TLS1_VERSION && s->version <= TLS1_1_VERSION) {
1419 rr->length = 0;
1420 goto start;
1421 }
1422 #endif
1423 al = SSL_AD_UNEXPECTED_MESSAGE;
1424 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_R_UNEXPECTED_RECORD);
1425 goto f_err;
1426 case SSL3_RT_CHANGE_CIPHER_SPEC:
1427 case SSL3_RT_ALERT:
1428 case SSL3_RT_HANDSHAKE:
1429 /*
1430 * we already handled all of these, with the possible exception of
1431 * SSL3_RT_HANDSHAKE when s->in_handshake is set, but that should not
1432 * happen when type != rr->type
1433 */
1434 al = SSL_AD_UNEXPECTED_MESSAGE;
1435 SSLerr(SSL_F_SSL3_READ_BYTES, ERR_R_INTERNAL_ERROR);
1436 goto f_err;
1437 case SSL3_RT_APPLICATION_DATA:
1438 /*
1439 * At this point, we were expecting handshake data, but have
1440 * application data. If the library was running inside ssl3_read()
1441 * (i.e. in_read_app_data is set) and it makes sense to read
1442 * application data at this point (session renegotiation not yet
1443 * started), we will indulge it.
1444 */
1445 if (s->s3->in_read_app_data &&
1446 (s->s3->total_renegotiations != 0) &&
1447 (((s->state & SSL_ST_CONNECT) &&
1448 (s->state >= SSL3_ST_CW_CLNT_HELLO_A) &&
1449 (s->state <= SSL3_ST_CR_SRVR_HELLO_A)
1450 ) || ((s->state & SSL_ST_ACCEPT) &&
1451 (s->state <= SSL3_ST_SW_HELLO_REQ_A) &&
1452 (s->state >= SSL3_ST_SR_CLNT_HELLO_A)
1453 )
1454 )) {
1455 s->s3->in_read_app_data = 2;
1456 return (-1);
1457 } else {
1458 al = SSL_AD_UNEXPECTED_MESSAGE;
1459 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_R_UNEXPECTED_RECORD);
1460 goto f_err;
1461 }
1462 }
1463 /* not reached */
1464
1465 f_err:
1466 ssl3_send_alert(s, SSL3_AL_FATAL, al);
1467 err:
1468 return (-1);
1469 }
1470
ssl3_do_change_cipher_spec(SSL * s)1471 int ssl3_do_change_cipher_spec(SSL *s)
1472 {
1473 int i;
1474 const char *sender;
1475 int slen;
1476
1477 if (s->state & SSL_ST_ACCEPT)
1478 i = SSL3_CHANGE_CIPHER_SERVER_READ;
1479 else
1480 i = SSL3_CHANGE_CIPHER_CLIENT_READ;
1481
1482 if (s->s3->tmp.key_block == NULL) {
1483 if (s->session == NULL || s->session->master_key_length == 0) {
1484 /* might happen if dtls1_read_bytes() calls this */
1485 SSLerr(SSL_F_SSL3_DO_CHANGE_CIPHER_SPEC,
1486 SSL_R_CCS_RECEIVED_EARLY);
1487 return (0);
1488 }
1489
1490 s->session->cipher = s->s3->tmp.new_cipher;
1491 if (!s->method->ssl3_enc->setup_key_block(s))
1492 return (0);
1493 }
1494
1495 if (!s->method->ssl3_enc->change_cipher_state(s, i))
1496 return (0);
1497
1498 /*
1499 * we have to record the message digest at this point so we can get it
1500 * before we read the finished message
1501 */
1502 if (s->state & SSL_ST_CONNECT) {
1503 sender = s->method->ssl3_enc->server_finished_label;
1504 slen = s->method->ssl3_enc->server_finished_label_len;
1505 } else {
1506 sender = s->method->ssl3_enc->client_finished_label;
1507 slen = s->method->ssl3_enc->client_finished_label_len;
1508 }
1509
1510 i = s->method->ssl3_enc->final_finish_mac(s,
1511 sender, slen,
1512 s->s3->tmp.peer_finish_md);
1513 if (i == 0) {
1514 SSLerr(SSL_F_SSL3_DO_CHANGE_CIPHER_SPEC, ERR_R_INTERNAL_ERROR);
1515 return 0;
1516 }
1517 s->s3->tmp.peer_finish_md_len = i;
1518
1519 return (1);
1520 }
1521
ssl3_send_alert(SSL * s,int level,int desc)1522 int ssl3_send_alert(SSL *s, int level, int desc)
1523 {
1524 /* Map tls/ssl alert value to correct one */
1525 desc = s->method->ssl3_enc->alert_value(desc);
1526 if (s->version == SSL3_VERSION && desc == SSL_AD_PROTOCOL_VERSION)
1527 desc = SSL_AD_HANDSHAKE_FAILURE; /* SSL 3.0 does not have
1528 * protocol_version alerts */
1529 if (desc < 0)
1530 return -1;
1531 /* If a fatal one, remove from cache */
1532 if ((level == 2) && (s->session != NULL))
1533 SSL_CTX_remove_session(s->ctx, s->session);
1534
1535 s->s3->alert_dispatch = 1;
1536 s->s3->send_alert[0] = level;
1537 s->s3->send_alert[1] = desc;
1538 if (s->s3->wbuf.left == 0) /* data still being written out? */
1539 return s->method->ssl_dispatch_alert(s);
1540 /*
1541 * else data is still being written out, we will get written some time in
1542 * the future
1543 */
1544 return -1;
1545 }
1546
ssl3_dispatch_alert(SSL * s)1547 int ssl3_dispatch_alert(SSL *s)
1548 {
1549 int i, j;
1550 void (*cb) (const SSL *ssl, int type, int val) = NULL;
1551
1552 s->s3->alert_dispatch = 0;
1553 i = do_ssl3_write(s, SSL3_RT_ALERT, &s->s3->send_alert[0], 2, 0);
1554 if (i <= 0) {
1555 s->s3->alert_dispatch = 1;
1556 } else {
1557 /*
1558 * Alert sent to BIO. If it is important, flush it now. If the
1559 * message does not get sent due to non-blocking IO, we will not
1560 * worry too much.
1561 */
1562 if (s->s3->send_alert[0] == SSL3_AL_FATAL)
1563 (void)BIO_flush(s->wbio);
1564
1565 if (s->msg_callback)
1566 s->msg_callback(1, s->version, SSL3_RT_ALERT, s->s3->send_alert,
1567 2, s, s->msg_callback_arg);
1568
1569 if (s->info_callback != NULL)
1570 cb = s->info_callback;
1571 else if (s->ctx->info_callback != NULL)
1572 cb = s->ctx->info_callback;
1573
1574 if (cb != NULL) {
1575 j = (s->s3->send_alert[0] << 8) | s->s3->send_alert[1];
1576 cb(s, SSL_CB_WRITE_ALERT, j);
1577 }
1578 }
1579 return (i);
1580 }
1581