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 #ifndef EVP_CIPH_FLAG_TLS1_1_MULTIBLOCK
122 # define EVP_CIPH_FLAG_TLS1_1_MULTIBLOCK 0
123 #endif
124
125 #if defined(OPENSSL_SMALL_FOOTPRINT) || \
126 !( defined(AES_ASM) && ( \
127 defined(__x86_64) || defined(__x86_64__) || \
128 defined(_M_AMD64) || defined(_M_X64) || \
129 defined(__INTEL__) ) \
130 )
131 # undef EVP_CIPH_FLAG_TLS1_1_MULTIBLOCK
132 # define EVP_CIPH_FLAG_TLS1_1_MULTIBLOCK 0
133 #endif
134
135 static int do_ssl3_write(SSL *s, int type, const unsigned char *buf,
136 unsigned int len, int create_empty_fragment);
137 static int ssl3_get_record(SSL *s);
138
139 /*
140 * Return values are as per SSL_read()
141 */
ssl3_read_n(SSL * s,int n,int max,int extend)142 int ssl3_read_n(SSL *s, int n, int max, int extend)
143 {
144 /*
145 * If extend == 0, obtain new n-byte packet; if extend == 1, increase
146 * packet by another n bytes. The packet will be in the sub-array of
147 * s->s3->rbuf.buf specified by s->packet and s->packet_length. (If
148 * s->read_ahead is set, 'max' bytes may be stored in rbuf [plus
149 * s->packet_length bytes if extend == 1].)
150 */
151 int i, len, left;
152 long align = 0;
153 unsigned char *pkt;
154 SSL3_BUFFER *rb;
155
156 if (n <= 0)
157 return n;
158
159 rb = &(s->s3->rbuf);
160 if (rb->buf == NULL)
161 if (!ssl3_setup_read_buffer(s))
162 return -1;
163
164 left = rb->left;
165 #if defined(SSL3_ALIGN_PAYLOAD) && SSL3_ALIGN_PAYLOAD!=0
166 align = (long)rb->buf + SSL3_RT_HEADER_LENGTH;
167 align = (-align) & (SSL3_ALIGN_PAYLOAD - 1);
168 #endif
169
170 if (!extend) {
171 /* start with empty packet ... */
172 if (left == 0)
173 rb->offset = align;
174 else if (align != 0 && left >= SSL3_RT_HEADER_LENGTH) {
175 /*
176 * check if next packet length is large enough to justify payload
177 * alignment...
178 */
179 pkt = rb->buf + rb->offset;
180 if (pkt[0] == SSL3_RT_APPLICATION_DATA
181 && (pkt[3] << 8 | pkt[4]) >= 128) {
182 /*
183 * Note that even if packet is corrupted and its length field
184 * is insane, we can only be led to wrong decision about
185 * whether memmove will occur or not. Header values has no
186 * effect on memmove arguments and therefore no buffer
187 * overrun can be triggered.
188 */
189 memmove(rb->buf + align, pkt, left);
190 rb->offset = align;
191 }
192 }
193 s->packet = rb->buf + rb->offset;
194 s->packet_length = 0;
195 /* ... now we can act as if 'extend' was set */
196 }
197
198 /*
199 * For DTLS/UDP reads should not span multiple packets because the read
200 * operation returns the whole packet at once (as long as it fits into
201 * the buffer).
202 */
203 if (SSL_IS_DTLS(s)) {
204 if (left == 0 && extend)
205 return 0;
206 if (left > 0 && n > left)
207 n = left;
208 }
209
210 /* if there is enough in the buffer from a previous read, take some */
211 if (left >= n) {
212 s->packet_length += n;
213 rb->left = left - n;
214 rb->offset += n;
215 return (n);
216 }
217
218 /* else we need to read more data */
219
220 len = s->packet_length;
221 pkt = rb->buf + align;
222 /*
223 * Move any available bytes to front of buffer: 'len' bytes already
224 * pointed to by 'packet', 'left' extra ones at the end
225 */
226 if (s->packet != pkt) { /* len > 0 */
227 memmove(pkt, s->packet, len + left);
228 s->packet = pkt;
229 rb->offset = len + align;
230 }
231
232 if (n > (int)(rb->len - rb->offset)) { /* does not happen */
233 SSLerr(SSL_F_SSL3_READ_N, ERR_R_INTERNAL_ERROR);
234 return -1;
235 }
236
237 /* We always act like read_ahead is set for DTLS */
238 if (!s->read_ahead && !SSL_IS_DTLS(s))
239 /* ignore max parameter */
240 max = n;
241 else {
242 if (max < n)
243 max = n;
244 if (max > (int)(rb->len - rb->offset))
245 max = rb->len - rb->offset;
246 }
247
248 while (left < n) {
249 /*
250 * Now we have len+left bytes at the front of s->s3->rbuf.buf and
251 * need to read in more until we have len+n (up to len+max if
252 * possible)
253 */
254
255 clear_sys_error();
256 if (s->rbio != NULL) {
257 s->rwstate = SSL_READING;
258 i = BIO_read(s->rbio, pkt + len + left, max - left);
259 } else {
260 SSLerr(SSL_F_SSL3_READ_N, SSL_R_READ_BIO_NOT_SET);
261 i = -1;
262 }
263
264 if (i <= 0) {
265 rb->left = left;
266 if (s->mode & SSL_MODE_RELEASE_BUFFERS && !SSL_IS_DTLS(s))
267 if (len + left == 0)
268 ssl3_release_read_buffer(s);
269 return (i);
270 }
271 left += i;
272 /*
273 * reads should *never* span multiple packets for DTLS because the
274 * underlying transport protocol is message oriented as opposed to
275 * byte oriented as in the TLS case.
276 */
277 if (SSL_IS_DTLS(s)) {
278 if (n > left)
279 n = left; /* makes the while condition false */
280 }
281 }
282
283 /* done reading, now the book-keeping */
284 rb->offset += n;
285 rb->left = left - n;
286 s->packet_length += n;
287 s->rwstate = SSL_NOTHING;
288 return (n);
289 }
290
291 /*
292 * MAX_EMPTY_RECORDS defines the number of consecutive, empty records that
293 * will be processed per call to ssl3_get_record. Without this limit an
294 * attacker could send empty records at a faster rate than we can process and
295 * cause ssl3_get_record to loop forever.
296 */
297 #define MAX_EMPTY_RECORDS 32
298
299 /*-
300 * Call this to get a new input record.
301 * It will return <= 0 if more data is needed, normally due to an error
302 * or non-blocking IO.
303 * When it finishes, one packet has been decoded and can be found in
304 * ssl->s3->rrec.type - is the type of record
305 * ssl->s3->rrec.data, - data
306 * ssl->s3->rrec.length, - number of bytes
307 */
308 /* used only by ssl3_read_bytes */
ssl3_get_record(SSL * s)309 static int ssl3_get_record(SSL *s)
310 {
311 int ssl_major, ssl_minor, al;
312 int enc_err, n, i, ret = -1;
313 SSL3_RECORD *rr;
314 SSL_SESSION *sess;
315 unsigned char *p;
316 unsigned char md[EVP_MAX_MD_SIZE];
317 short version;
318 unsigned mac_size, orig_len;
319 size_t extra;
320 unsigned empty_record_count = 0;
321
322 rr = &(s->s3->rrec);
323 sess = s->session;
324
325 if (s->options & SSL_OP_MICROSOFT_BIG_SSLV3_BUFFER)
326 extra = SSL3_RT_MAX_EXTRA;
327 else
328 extra = 0;
329 if (extra && !s->s3->init_extra) {
330 /*
331 * An application error: SLS_OP_MICROSOFT_BIG_SSLV3_BUFFER set after
332 * ssl3_setup_buffers() was done
333 */
334 SSLerr(SSL_F_SSL3_GET_RECORD, ERR_R_INTERNAL_ERROR);
335 return -1;
336 }
337
338 again:
339 /* check if we have the header */
340 if ((s->rstate != SSL_ST_READ_BODY) ||
341 (s->packet_length < SSL3_RT_HEADER_LENGTH)) {
342 n = ssl3_read_n(s, SSL3_RT_HEADER_LENGTH, s->s3->rbuf.len, 0);
343 if (n <= 0)
344 return (n); /* error or non-blocking */
345 s->rstate = SSL_ST_READ_BODY;
346
347 p = s->packet;
348 if (s->msg_callback)
349 s->msg_callback(0, 0, SSL3_RT_HEADER, p, 5, s,
350 s->msg_callback_arg);
351
352 /* Pull apart the header into the SSL3_RECORD */
353 rr->type = *(p++);
354 ssl_major = *(p++);
355 ssl_minor = *(p++);
356 version = (ssl_major << 8) | ssl_minor;
357 n2s(p, rr->length);
358 #if 0
359 fprintf(stderr, "Record type=%d, Length=%d\n", rr->type, rr->length);
360 #endif
361
362 /* Lets check version */
363 if (!s->first_packet) {
364 if (version != s->version) {
365 SSLerr(SSL_F_SSL3_GET_RECORD, SSL_R_WRONG_VERSION_NUMBER);
366 if ((s->version & 0xFF00) == (version & 0xFF00)
367 && !s->enc_write_ctx && !s->write_hash) {
368 if (rr->type == SSL3_RT_ALERT) {
369 /*
370 * The record is using an incorrect version number, but
371 * what we've got appears to be an alert. We haven't
372 * read the body yet to check whether its a fatal or
373 * not - but chances are it is. We probably shouldn't
374 * send a fatal alert back. We'll just end.
375 */
376 goto err;
377 }
378 /*
379 * Send back error using their minor version number :-)
380 */
381 s->version = (unsigned short)version;
382 }
383 al = SSL_AD_PROTOCOL_VERSION;
384 goto f_err;
385 }
386 }
387
388 if ((version >> 8) != SSL3_VERSION_MAJOR) {
389 SSLerr(SSL_F_SSL3_GET_RECORD, SSL_R_WRONG_VERSION_NUMBER);
390 goto err;
391 }
392
393 if (rr->length > s->s3->rbuf.len - SSL3_RT_HEADER_LENGTH) {
394 al = SSL_AD_RECORD_OVERFLOW;
395 SSLerr(SSL_F_SSL3_GET_RECORD, SSL_R_PACKET_LENGTH_TOO_LONG);
396 goto f_err;
397 }
398
399 /* now s->rstate == SSL_ST_READ_BODY */
400 }
401
402 /* s->rstate == SSL_ST_READ_BODY, get and decode the data */
403
404 if (rr->length > s->packet_length - SSL3_RT_HEADER_LENGTH) {
405 /* now s->packet_length == SSL3_RT_HEADER_LENGTH */
406 i = rr->length;
407 n = ssl3_read_n(s, i, i, 1);
408 if (n <= 0)
409 return (n); /* error or non-blocking io */
410 /*
411 * now n == rr->length, and s->packet_length == SSL3_RT_HEADER_LENGTH
412 * + rr->length
413 */
414 }
415
416 s->rstate = SSL_ST_READ_HEADER; /* set state for later operations */
417
418 /*
419 * At this point, s->packet_length == SSL3_RT_HEADER_LNGTH + rr->length,
420 * and we have that many bytes in s->packet
421 */
422 rr->input = &(s->packet[SSL3_RT_HEADER_LENGTH]);
423
424 /*
425 * ok, we can now read from 's->packet' data into 'rr' rr->input points
426 * at rr->length bytes, which need to be copied into rr->data by either
427 * the decryption or by the decompression When the data is 'copied' into
428 * the rr->data buffer, rr->input will be pointed at the new buffer
429 */
430
431 /*
432 * We now have - encrypted [ MAC [ compressed [ plain ] ] ] rr->length
433 * bytes of encrypted compressed stuff.
434 */
435
436 /* check is not needed I believe */
437 if (rr->length > SSL3_RT_MAX_ENCRYPTED_LENGTH + extra) {
438 al = SSL_AD_RECORD_OVERFLOW;
439 SSLerr(SSL_F_SSL3_GET_RECORD, SSL_R_ENCRYPTED_LENGTH_TOO_LONG);
440 goto f_err;
441 }
442
443 /* decrypt in place in 'rr->input' */
444 rr->data = rr->input;
445
446 enc_err = s->method->ssl3_enc->enc(s, 0);
447 /*-
448 * enc_err is:
449 * 0: (in non-constant time) if the record is publically invalid.
450 * 1: if the padding is valid
451 * -1: if the padding is invalid
452 */
453 if (enc_err == 0) {
454 al = SSL_AD_DECRYPTION_FAILED;
455 SSLerr(SSL_F_SSL3_GET_RECORD, SSL_R_BLOCK_CIPHER_PAD_IS_WRONG);
456 goto f_err;
457 }
458 #ifdef TLS_DEBUG
459 printf("dec %d\n", rr->length);
460 {
461 unsigned int z;
462 for (z = 0; z < rr->length; z++)
463 printf("%02X%c", rr->data[z], ((z + 1) % 16) ? ' ' : '\n');
464 }
465 printf("\n");
466 #endif
467
468 /* r->length is now the compressed data plus mac */
469 if ((sess != NULL) &&
470 (s->enc_read_ctx != NULL) && (EVP_MD_CTX_md(s->read_hash) != NULL)) {
471 /* s->read_hash != NULL => mac_size != -1 */
472 unsigned char *mac = NULL;
473 unsigned char mac_tmp[EVP_MAX_MD_SIZE];
474 mac_size = EVP_MD_CTX_size(s->read_hash);
475 OPENSSL_assert(mac_size <= EVP_MAX_MD_SIZE);
476
477 /*
478 * kludge: *_cbc_remove_padding passes padding length in rr->type
479 */
480 orig_len = rr->length + ((unsigned int)rr->type >> 8);
481
482 /*
483 * orig_len is the length of the record before any padding was
484 * removed. This is public information, as is the MAC in use,
485 * therefore we can safely process the record in a different amount
486 * of time if it's too short to possibly contain a MAC.
487 */
488 if (orig_len < mac_size ||
489 /* CBC records must have a padding length byte too. */
490 (EVP_CIPHER_CTX_mode(s->enc_read_ctx) == EVP_CIPH_CBC_MODE &&
491 orig_len < mac_size + 1)) {
492 al = SSL_AD_DECODE_ERROR;
493 SSLerr(SSL_F_SSL3_GET_RECORD, SSL_R_LENGTH_TOO_SHORT);
494 goto f_err;
495 }
496
497 if (EVP_CIPHER_CTX_mode(s->enc_read_ctx) == EVP_CIPH_CBC_MODE) {
498 /*
499 * We update the length so that the TLS header bytes can be
500 * constructed correctly but we need to extract the MAC in
501 * constant time from within the record, without leaking the
502 * contents of the padding bytes.
503 */
504 mac = mac_tmp;
505 ssl3_cbc_copy_mac(mac_tmp, rr, mac_size, orig_len);
506 rr->length -= mac_size;
507 } else {
508 /*
509 * In this case there's no padding, so |orig_len| equals
510 * |rec->length| and we checked that there's enough bytes for
511 * |mac_size| above.
512 */
513 rr->length -= mac_size;
514 mac = &rr->data[rr->length];
515 }
516
517 i = s->method->ssl3_enc->mac(s, md, 0 /* not send */ );
518 if (i < 0 || mac == NULL
519 || CRYPTO_memcmp(md, mac, (size_t)mac_size) != 0)
520 enc_err = -1;
521 if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH + extra + mac_size)
522 enc_err = -1;
523 }
524
525 if (enc_err < 0) {
526 /*
527 * A separate 'decryption_failed' alert was introduced with TLS 1.0,
528 * SSL 3.0 only has 'bad_record_mac'. But unless a decryption
529 * failure is directly visible from the ciphertext anyway, we should
530 * not reveal which kind of error occured -- this might become
531 * visible to an attacker (e.g. via a logfile)
532 */
533 al = SSL_AD_BAD_RECORD_MAC;
534 SSLerr(SSL_F_SSL3_GET_RECORD,
535 SSL_R_DECRYPTION_FAILED_OR_BAD_RECORD_MAC);
536 goto f_err;
537 }
538
539 /* r->length is now just compressed */
540 if (s->expand != NULL) {
541 if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH + extra) {
542 al = SSL_AD_RECORD_OVERFLOW;
543 SSLerr(SSL_F_SSL3_GET_RECORD, SSL_R_COMPRESSED_LENGTH_TOO_LONG);
544 goto f_err;
545 }
546 if (!ssl3_do_uncompress(s)) {
547 al = SSL_AD_DECOMPRESSION_FAILURE;
548 SSLerr(SSL_F_SSL3_GET_RECORD, SSL_R_BAD_DECOMPRESSION);
549 goto f_err;
550 }
551 }
552
553 if (rr->length > SSL3_RT_MAX_PLAIN_LENGTH + extra) {
554 al = SSL_AD_RECORD_OVERFLOW;
555 SSLerr(SSL_F_SSL3_GET_RECORD, SSL_R_DATA_LENGTH_TOO_LONG);
556 goto f_err;
557 }
558
559 rr->off = 0;
560 /*-
561 * So at this point the following is true
562 * ssl->s3->rrec.type is the type of record
563 * ssl->s3->rrec.length == number of bytes in record
564 * ssl->s3->rrec.off == offset to first valid byte
565 * ssl->s3->rrec.data == where to take bytes from, increment
566 * after use :-).
567 */
568
569 /* we have pulled in a full packet so zero things */
570 s->packet_length = 0;
571
572 /* just read a 0 length packet */
573 if (rr->length == 0) {
574 empty_record_count++;
575 if (empty_record_count > MAX_EMPTY_RECORDS) {
576 al = SSL_AD_UNEXPECTED_MESSAGE;
577 SSLerr(SSL_F_SSL3_GET_RECORD, SSL_R_RECORD_TOO_SMALL);
578 goto f_err;
579 }
580 goto again;
581 }
582 #if 0
583 fprintf(stderr, "Ultimate Record type=%d, Length=%d\n", rr->type,
584 rr->length);
585 #endif
586
587 return (1);
588
589 f_err:
590 ssl3_send_alert(s, SSL3_AL_FATAL, al);
591 err:
592 return (ret);
593 }
594
ssl3_do_uncompress(SSL * ssl)595 int ssl3_do_uncompress(SSL *ssl)
596 {
597 #ifndef OPENSSL_NO_COMP
598 int i;
599 SSL3_RECORD *rr;
600
601 rr = &(ssl->s3->rrec);
602 i = COMP_expand_block(ssl->expand, rr->comp,
603 SSL3_RT_MAX_PLAIN_LENGTH, rr->data,
604 (int)rr->length);
605 if (i < 0)
606 return (0);
607 else
608 rr->length = i;
609 rr->data = rr->comp;
610 #endif
611 return (1);
612 }
613
ssl3_do_compress(SSL * ssl)614 int ssl3_do_compress(SSL *ssl)
615 {
616 #ifndef OPENSSL_NO_COMP
617 int i;
618 SSL3_RECORD *wr;
619
620 wr = &(ssl->s3->wrec);
621 i = COMP_compress_block(ssl->compress, wr->data,
622 SSL3_RT_MAX_COMPRESSED_LENGTH,
623 wr->input, (int)wr->length);
624 if (i < 0)
625 return (0);
626 else
627 wr->length = i;
628
629 wr->input = wr->data;
630 #endif
631 return (1);
632 }
633
634 /*
635 * Call this to write data in records of type 'type' It will return <= 0 if
636 * not all data has been sent or non-blocking IO.
637 */
ssl3_write_bytes(SSL * s,int type,const void * buf_,int len)638 int ssl3_write_bytes(SSL *s, int type, const void *buf_, int len)
639 {
640 const unsigned char *buf = buf_;
641 int tot;
642 unsigned int n, nw;
643 #if !defined(OPENSSL_NO_MULTIBLOCK) && EVP_CIPH_FLAG_TLS1_1_MULTIBLOCK
644 unsigned int max_send_fragment;
645 #endif
646 SSL3_BUFFER *wb = &(s->s3->wbuf);
647 int i;
648
649 s->rwstate = SSL_NOTHING;
650 OPENSSL_assert(s->s3->wnum <= INT_MAX);
651 tot = s->s3->wnum;
652 s->s3->wnum = 0;
653
654 if (SSL_in_init(s) && !s->in_handshake) {
655 i = s->handshake_func(s);
656 if (i < 0)
657 return (i);
658 if (i == 0) {
659 SSLerr(SSL_F_SSL3_WRITE_BYTES, SSL_R_SSL_HANDSHAKE_FAILURE);
660 return -1;
661 }
662 }
663
664 /*
665 * ensure that if we end up with a smaller value of data to write out
666 * than the the original len from a write which didn't complete for
667 * non-blocking I/O and also somehow ended up avoiding the check for
668 * this in ssl3_write_pending/SSL_R_BAD_WRITE_RETRY as it must never be
669 * possible to end up with (len-tot) as a large number that will then
670 * promptly send beyond the end of the users buffer ... so we trap and
671 * report the error in a way the user will notice
672 */
673 if (len < tot) {
674 SSLerr(SSL_F_SSL3_WRITE_BYTES, SSL_R_BAD_LENGTH);
675 return (-1);
676 }
677
678 /*
679 * first check if there is a SSL3_BUFFER still being written out. This
680 * will happen with non blocking IO
681 */
682 if (wb->left != 0) {
683 i = ssl3_write_pending(s, type, &buf[tot], s->s3->wpend_tot);
684 if (i <= 0) {
685 /* XXX should we ssl3_release_write_buffer if i<0? */
686 s->s3->wnum = tot;
687 return i;
688 }
689 tot += i; /* this might be last fragment */
690 }
691 #if !defined(OPENSSL_NO_MULTIBLOCK) && EVP_CIPH_FLAG_TLS1_1_MULTIBLOCK
692 /*
693 * Depending on platform multi-block can deliver several *times*
694 * better performance. Downside is that it has to allocate
695 * jumbo buffer to accomodate up to 8 records, but the
696 * compromise is considered worthy.
697 */
698 if (type == SSL3_RT_APPLICATION_DATA &&
699 len >= 4 * (int)(max_send_fragment = s->max_send_fragment) &&
700 s->compress == NULL && s->msg_callback == NULL &&
701 SSL_USE_EXPLICIT_IV(s) &&
702 EVP_CIPHER_flags(s->enc_write_ctx->cipher) &
703 EVP_CIPH_FLAG_TLS1_1_MULTIBLOCK) {
704 unsigned char aad[13];
705 EVP_CTRL_TLS1_1_MULTIBLOCK_PARAM mb_param;
706 int packlen;
707
708 /* minimize address aliasing conflicts */
709 if ((max_send_fragment & 0xfff) == 0)
710 max_send_fragment -= 512;
711
712 if (tot == 0 || wb->buf == NULL) { /* allocate jumbo buffer */
713 ssl3_release_write_buffer(s);
714
715 packlen = EVP_CIPHER_CTX_ctrl(s->enc_write_ctx,
716 EVP_CTRL_TLS1_1_MULTIBLOCK_MAX_BUFSIZE,
717 max_send_fragment, NULL);
718
719 if (len >= 8 * (int)max_send_fragment)
720 packlen *= 8;
721 else
722 packlen *= 4;
723
724 wb->buf = OPENSSL_malloc(packlen);
725 if (!wb->buf) {
726 SSLerr(SSL_F_SSL3_WRITE_BYTES, ERR_R_MALLOC_FAILURE);
727 return -1;
728 }
729 wb->len = packlen;
730 } else if (tot == len) { /* done? */
731 OPENSSL_free(wb->buf); /* free jumbo buffer */
732 wb->buf = NULL;
733 return tot;
734 }
735
736 n = (len - tot);
737 for (;;) {
738 if (n < 4 * max_send_fragment) {
739 OPENSSL_free(wb->buf); /* free jumbo buffer */
740 wb->buf = NULL;
741 break;
742 }
743
744 if (s->s3->alert_dispatch) {
745 i = s->method->ssl_dispatch_alert(s);
746 if (i <= 0) {
747 s->s3->wnum = tot;
748 return i;
749 }
750 }
751
752 if (n >= 8 * max_send_fragment)
753 nw = max_send_fragment * (mb_param.interleave = 8);
754 else
755 nw = max_send_fragment * (mb_param.interleave = 4);
756
757 memcpy(aad, s->s3->write_sequence, 8);
758 aad[8] = type;
759 aad[9] = (unsigned char)(s->version >> 8);
760 aad[10] = (unsigned char)(s->version);
761 aad[11] = 0;
762 aad[12] = 0;
763 mb_param.out = NULL;
764 mb_param.inp = aad;
765 mb_param.len = nw;
766
767 packlen = EVP_CIPHER_CTX_ctrl(s->enc_write_ctx,
768 EVP_CTRL_TLS1_1_MULTIBLOCK_AAD,
769 sizeof(mb_param), &mb_param);
770
771 if (packlen <= 0 || packlen > (int)wb->len) { /* never happens */
772 OPENSSL_free(wb->buf); /* free jumbo buffer */
773 wb->buf = NULL;
774 break;
775 }
776
777 mb_param.out = wb->buf;
778 mb_param.inp = &buf[tot];
779 mb_param.len = nw;
780
781 if (EVP_CIPHER_CTX_ctrl(s->enc_write_ctx,
782 EVP_CTRL_TLS1_1_MULTIBLOCK_ENCRYPT,
783 sizeof(mb_param), &mb_param) <= 0)
784 return -1;
785
786 s->s3->write_sequence[7] += mb_param.interleave;
787 if (s->s3->write_sequence[7] < mb_param.interleave) {
788 int j = 6;
789 while (j >= 0 && (++s->s3->write_sequence[j--]) == 0) ;
790 }
791
792 wb->offset = 0;
793 wb->left = packlen;
794
795 s->s3->wpend_tot = nw;
796 s->s3->wpend_buf = &buf[tot];
797 s->s3->wpend_type = type;
798 s->s3->wpend_ret = nw;
799
800 i = ssl3_write_pending(s, type, &buf[tot], nw);
801 if (i <= 0) {
802 if (i < 0 && (!s->wbio || !BIO_should_retry(s->wbio))) {
803 OPENSSL_free(wb->buf);
804 wb->buf = NULL;
805 }
806 s->s3->wnum = tot;
807 return i;
808 }
809 if (i == (int)n) {
810 OPENSSL_free(wb->buf); /* free jumbo buffer */
811 wb->buf = NULL;
812 return tot + i;
813 }
814 n -= i;
815 tot += i;
816 }
817 } else
818 #endif
819 if (tot == len) { /* done? */
820 if (s->mode & SSL_MODE_RELEASE_BUFFERS && !SSL_IS_DTLS(s))
821 ssl3_release_write_buffer(s);
822
823 return tot;
824 }
825
826 n = (len - tot);
827 for (;;) {
828 if (n > s->max_send_fragment)
829 nw = s->max_send_fragment;
830 else
831 nw = n;
832
833 i = do_ssl3_write(s, type, &(buf[tot]), nw, 0);
834 if (i <= 0) {
835 /* XXX should we ssl3_release_write_buffer if i<0? */
836 s->s3->wnum = tot;
837 return i;
838 }
839
840 if ((i == (int)n) ||
841 (type == SSL3_RT_APPLICATION_DATA &&
842 (s->mode & SSL_MODE_ENABLE_PARTIAL_WRITE))) {
843 /*
844 * next chunk of data should get another prepended empty fragment
845 * in ciphersuites with known-IV weakness:
846 */
847 s->s3->empty_fragment_done = 0;
848
849 if ((i == (int)n) && s->mode & SSL_MODE_RELEASE_BUFFERS &&
850 !SSL_IS_DTLS(s))
851 ssl3_release_write_buffer(s);
852
853 return tot + i;
854 }
855
856 n -= i;
857 tot += i;
858 }
859 }
860
do_ssl3_write(SSL * s,int type,const unsigned char * buf,unsigned int len,int create_empty_fragment)861 static int do_ssl3_write(SSL *s, int type, const unsigned char *buf,
862 unsigned int len, int create_empty_fragment)
863 {
864 unsigned char *p, *plen;
865 int i, mac_size, clear = 0;
866 int prefix_len = 0;
867 int eivlen;
868 long align = 0;
869 SSL3_RECORD *wr;
870 SSL3_BUFFER *wb = &(s->s3->wbuf);
871 SSL_SESSION *sess;
872
873 /*
874 * first check if there is a SSL3_BUFFER still being written out. This
875 * will happen with non blocking IO
876 */
877 if (wb->left != 0)
878 return (ssl3_write_pending(s, type, buf, len));
879
880 /* If we have an alert to send, lets send it */
881 if (s->s3->alert_dispatch) {
882 i = s->method->ssl_dispatch_alert(s);
883 if (i <= 0)
884 return (i);
885 /* if it went, fall through and send more stuff */
886 }
887
888 if (wb->buf == NULL)
889 if (!ssl3_setup_write_buffer(s))
890 return -1;
891
892 if (len == 0 && !create_empty_fragment)
893 return 0;
894
895 wr = &(s->s3->wrec);
896 sess = s->session;
897
898 if ((sess == NULL) ||
899 (s->enc_write_ctx == NULL) ||
900 (EVP_MD_CTX_md(s->write_hash) == NULL)) {
901 #if 1
902 clear = s->enc_write_ctx ? 0 : 1; /* must be AEAD cipher */
903 #else
904 clear = 1;
905 #endif
906 mac_size = 0;
907 } else {
908 mac_size = EVP_MD_CTX_size(s->write_hash);
909 if (mac_size < 0)
910 goto err;
911 }
912
913 /*
914 * 'create_empty_fragment' is true only when this function calls itself
915 */
916 if (!clear && !create_empty_fragment && !s->s3->empty_fragment_done) {
917 /*
918 * countermeasure against known-IV weakness in CBC ciphersuites (see
919 * http://www.openssl.org/~bodo/tls-cbc.txt)
920 */
921
922 if (s->s3->need_empty_fragments && type == SSL3_RT_APPLICATION_DATA) {
923 /*
924 * recursive function call with 'create_empty_fragment' set; this
925 * prepares and buffers the data for an empty fragment (these
926 * 'prefix_len' bytes are sent out later together with the actual
927 * payload)
928 */
929 prefix_len = do_ssl3_write(s, type, buf, 0, 1);
930 if (prefix_len <= 0)
931 goto err;
932
933 if (prefix_len >
934 (SSL3_RT_HEADER_LENGTH + SSL3_RT_SEND_MAX_ENCRYPTED_OVERHEAD))
935 {
936 /* insufficient space */
937 SSLerr(SSL_F_DO_SSL3_WRITE, ERR_R_INTERNAL_ERROR);
938 goto err;
939 }
940 }
941
942 s->s3->empty_fragment_done = 1;
943 }
944
945 if (create_empty_fragment) {
946 #if defined(SSL3_ALIGN_PAYLOAD) && SSL3_ALIGN_PAYLOAD!=0
947 /*
948 * extra fragment would be couple of cipher blocks, which would be
949 * multiple of SSL3_ALIGN_PAYLOAD, so if we want to align the real
950 * payload, then we can just pretent we simply have two headers.
951 */
952 align = (long)wb->buf + 2 * SSL3_RT_HEADER_LENGTH;
953 align = (-align) & (SSL3_ALIGN_PAYLOAD - 1);
954 #endif
955 p = wb->buf + align;
956 wb->offset = align;
957 } else if (prefix_len) {
958 p = wb->buf + wb->offset + prefix_len;
959 } else {
960 #if defined(SSL3_ALIGN_PAYLOAD) && SSL3_ALIGN_PAYLOAD!=0
961 align = (long)wb->buf + SSL3_RT_HEADER_LENGTH;
962 align = (-align) & (SSL3_ALIGN_PAYLOAD - 1);
963 #endif
964 p = wb->buf + align;
965 wb->offset = align;
966 }
967
968 /* write the header */
969
970 *(p++) = type & 0xff;
971 wr->type = type;
972
973 *(p++) = (s->version >> 8);
974 /*
975 * Some servers hang if iniatial client hello is larger than 256 bytes
976 * and record version number > TLS 1.0
977 */
978 if (s->state == SSL3_ST_CW_CLNT_HELLO_B
979 && !s->renegotiate && TLS1_get_version(s) > TLS1_VERSION)
980 *(p++) = 0x1;
981 else
982 *(p++) = s->version & 0xff;
983
984 /* field where we are to write out packet length */
985 plen = p;
986 p += 2;
987 /* Explicit IV length, block ciphers appropriate version flag */
988 if (s->enc_write_ctx && SSL_USE_EXPLICIT_IV(s)) {
989 int mode = EVP_CIPHER_CTX_mode(s->enc_write_ctx);
990 if (mode == EVP_CIPH_CBC_MODE) {
991 eivlen = EVP_CIPHER_CTX_iv_length(s->enc_write_ctx);
992 if (eivlen <= 1)
993 eivlen = 0;
994 }
995 /* Need explicit part of IV for GCM mode */
996 else if (mode == EVP_CIPH_GCM_MODE)
997 eivlen = EVP_GCM_TLS_EXPLICIT_IV_LEN;
998 else
999 eivlen = 0;
1000 } else if (s->aead_write_ctx != NULL &&
1001 s->aead_write_ctx->variable_nonce_included_in_record) {
1002 eivlen = s->aead_write_ctx->variable_nonce_len;
1003 } else
1004 eivlen = 0;
1005
1006 /* lets setup the record stuff. */
1007 wr->data = p + eivlen;
1008 wr->length = (int)len;
1009 wr->input = (unsigned char *)buf;
1010
1011 /*
1012 * we now 'read' from wr->input, wr->length bytes into wr->data
1013 */
1014
1015 /* first we compress */
1016 if (s->compress != NULL) {
1017 if (!ssl3_do_compress(s)) {
1018 SSLerr(SSL_F_DO_SSL3_WRITE, SSL_R_COMPRESSION_FAILURE);
1019 goto err;
1020 }
1021 } else {
1022 memcpy(wr->data, wr->input, wr->length);
1023 wr->input = wr->data;
1024 }
1025
1026 /*
1027 * we should still have the output to wr->data and the input from
1028 * wr->input. Length should be wr->length. wr->data still points in the
1029 * wb->buf
1030 */
1031
1032 if (mac_size != 0) {
1033 if (s->method->ssl3_enc->mac(s, &(p[wr->length + eivlen]), 1) < 0)
1034 goto err;
1035 wr->length += mac_size;
1036 }
1037
1038 wr->input = p;
1039 wr->data = p;
1040
1041 if (eivlen) {
1042 /*
1043 * if (RAND_pseudo_bytes(p, eivlen) <= 0) goto err;
1044 */
1045 wr->length += eivlen;
1046 }
1047
1048 if (s->method->ssl3_enc->enc(s, 1) < 1)
1049 goto err;
1050
1051 /* record length after mac and block padding */
1052 s2n(wr->length, plen);
1053
1054 if (s->msg_callback)
1055 s->msg_callback(1, 0, SSL3_RT_HEADER, plen - 5, 5, s,
1056 s->msg_callback_arg);
1057
1058 /*
1059 * we should now have wr->data pointing to the encrypted data, which is
1060 * wr->length long
1061 */
1062 wr->type = type; /* not needed but helps for debugging */
1063 wr->length += SSL3_RT_HEADER_LENGTH;
1064
1065 if (create_empty_fragment) {
1066 /*
1067 * we are in a recursive call; just return the length, don't write
1068 * out anything here
1069 */
1070 return wr->length;
1071 }
1072
1073 /* now let's set up wb */
1074 wb->left = prefix_len + wr->length;
1075
1076 /*
1077 * memorize arguments so that ssl3_write_pending can detect bad write
1078 * retries later
1079 */
1080 s->s3->wpend_tot = len;
1081 s->s3->wpend_buf = buf;
1082 s->s3->wpend_type = type;
1083 s->s3->wpend_ret = len;
1084
1085 /* we now just need to write the buffer */
1086 return ssl3_write_pending(s, type, buf, len);
1087 err:
1088 return -1;
1089 }
1090
1091 /* if s->s3->wbuf.left != 0, we need to call this
1092 *
1093 * Return values are as per SSL_write(), i.e.
1094 */
ssl3_write_pending(SSL * s,int type,const unsigned char * buf,unsigned int len)1095 int ssl3_write_pending(SSL *s, int type, const unsigned char *buf,
1096 unsigned int len)
1097 {
1098 int i;
1099 SSL3_BUFFER *wb = &(s->s3->wbuf);
1100
1101 /* XXXX */
1102 if ((s->s3->wpend_tot > (int)len)
1103 || ((s->s3->wpend_buf != buf) &&
1104 !(s->mode & SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER))
1105 || (s->s3->wpend_type != type)) {
1106 SSLerr(SSL_F_SSL3_WRITE_PENDING, SSL_R_BAD_WRITE_RETRY);
1107 return (-1);
1108 }
1109
1110 for (;;) {
1111 clear_sys_error();
1112 if (s->wbio != NULL) {
1113 s->rwstate = SSL_WRITING;
1114 i = BIO_write(s->wbio,
1115 (char *)&(wb->buf[wb->offset]),
1116 (unsigned int)wb->left);
1117 } else {
1118 SSLerr(SSL_F_SSL3_WRITE_PENDING, SSL_R_BIO_NOT_SET);
1119 i = -1;
1120 }
1121 if (i == wb->left) {
1122 wb->left = 0;
1123 wb->offset += i;
1124 s->rwstate = SSL_NOTHING;
1125 return (s->s3->wpend_ret);
1126 } else if (i <= 0) {
1127 if (SSL_IS_DTLS(s)) {
1128 /*
1129 * For DTLS, just drop it. That's kind of the whole point in
1130 * using a datagram service
1131 */
1132 wb->left = 0;
1133 }
1134 return i;
1135 }
1136 wb->offset += i;
1137 wb->left -= i;
1138 }
1139 }
1140
1141 /*-
1142 * Return up to 'len' payload bytes received in 'type' records.
1143 * 'type' is one of the following:
1144 *
1145 * - SSL3_RT_HANDSHAKE (when ssl3_get_message calls us)
1146 * - SSL3_RT_APPLICATION_DATA (when ssl3_read calls us)
1147 * - 0 (during a shutdown, no data has to be returned)
1148 *
1149 * If we don't have stored data to work from, read a SSL/TLS record first
1150 * (possibly multiple records if we still don't have anything to return).
1151 *
1152 * This function must handle any surprises the peer may have for us, such as
1153 * Alert records (e.g. close_notify), ChangeCipherSpec records (not really
1154 * a surprise, but handled as if it were), or renegotiation requests.
1155 * Also if record payloads contain fragments too small to process, we store
1156 * them until there is enough for the respective protocol (the record protocol
1157 * may use arbitrary fragmentation and even interleaving):
1158 * Change cipher spec protocol
1159 * just 1 byte needed, no need for keeping anything stored
1160 * Alert protocol
1161 * 2 bytes needed (AlertLevel, AlertDescription)
1162 * Handshake protocol
1163 * 4 bytes needed (HandshakeType, uint24 length) -- we just have
1164 * to detect unexpected Client Hello and Hello Request messages
1165 * here, anything else is handled by higher layers
1166 * Application data protocol
1167 * none of our business
1168 */
ssl3_read_bytes(SSL * s,int type,unsigned char * buf,int len,int peek)1169 int ssl3_read_bytes(SSL *s, int type, unsigned char *buf, int len, int peek)
1170 {
1171 int al, i, j, ret;
1172 unsigned int n;
1173 SSL3_RECORD *rr;
1174 void (*cb) (const SSL *ssl, int type2, int val) = NULL;
1175
1176 if (s->s3->rbuf.buf == NULL) /* Not initialized yet */
1177 if (!ssl3_setup_read_buffer(s))
1178 return (-1);
1179
1180 if ((type && (type != SSL3_RT_APPLICATION_DATA)
1181 && (type != SSL3_RT_HANDSHAKE)) || (peek
1182 && (type !=
1183 SSL3_RT_APPLICATION_DATA))) {
1184 SSLerr(SSL_F_SSL3_READ_BYTES, ERR_R_INTERNAL_ERROR);
1185 return -1;
1186 }
1187
1188 if ((type == SSL3_RT_HANDSHAKE) && (s->s3->handshake_fragment_len > 0))
1189 /* (partially) satisfy request from storage */
1190 {
1191 unsigned char *src = s->s3->handshake_fragment;
1192 unsigned char *dst = buf;
1193 unsigned int k;
1194
1195 /* peek == 0 */
1196 n = 0;
1197 while ((len > 0) && (s->s3->handshake_fragment_len > 0)) {
1198 *dst++ = *src++;
1199 len--;
1200 s->s3->handshake_fragment_len--;
1201 n++;
1202 }
1203 /* move any remaining fragment bytes: */
1204 for (k = 0; k < s->s3->handshake_fragment_len; k++)
1205 s->s3->handshake_fragment[k] = *src++;
1206 return n;
1207 }
1208
1209 /*
1210 * Now s->s3->handshake_fragment_len == 0 if type == SSL3_RT_HANDSHAKE.
1211 */
1212
1213 if (!s->in_handshake && SSL_in_init(s)) {
1214 /* type == SSL3_RT_APPLICATION_DATA */
1215 i = s->handshake_func(s);
1216 if (i < 0)
1217 return (i);
1218 if (i == 0) {
1219 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_R_SSL_HANDSHAKE_FAILURE);
1220 return (-1);
1221 }
1222 }
1223 start:
1224 s->rwstate = SSL_NOTHING;
1225
1226 /*-
1227 * s->s3->rrec.type - is the type of record
1228 * s->s3->rrec.data, - data
1229 * s->s3->rrec.off, - offset into 'data' for next read
1230 * s->s3->rrec.length, - number of bytes.
1231 */
1232 rr = &(s->s3->rrec);
1233
1234 /* get new packet if necessary */
1235 if ((rr->length == 0) || (s->rstate == SSL_ST_READ_BODY)) {
1236 ret = ssl3_get_record(s);
1237 if (ret <= 0)
1238 return (ret);
1239 }
1240
1241 /*
1242 * Reset the count of consecutive warning alerts if we've got a non-empty
1243 * record that isn't an alert.
1244 */
1245 if (rr->type != SSL3_RT_ALERT && rr->length != 0)
1246 s->cert->alert_count = 0;
1247
1248 /* we now have a packet which can be read and processed */
1249
1250 if (s->s3->change_cipher_spec /* set when we receive ChangeCipherSpec,
1251 * reset by ssl3_get_finished */
1252 && (rr->type != SSL3_RT_HANDSHAKE)) {
1253 al = SSL_AD_UNEXPECTED_MESSAGE;
1254 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_R_DATA_BETWEEN_CCS_AND_FINISHED);
1255 goto f_err;
1256 }
1257
1258 /*
1259 * If the other end has shut down, throw anything we read away (even in
1260 * 'peek' mode)
1261 */
1262 if (s->shutdown & SSL_RECEIVED_SHUTDOWN) {
1263 rr->length = 0;
1264 s->rwstate = SSL_NOTHING;
1265 return (0);
1266 }
1267
1268 if (type == rr->type) { /* SSL3_RT_APPLICATION_DATA or
1269 * SSL3_RT_HANDSHAKE */
1270 /*
1271 * make sure that we are not getting application data when we are
1272 * doing a handshake for the first time
1273 */
1274 if (SSL_in_init(s) && (type == SSL3_RT_APPLICATION_DATA) &&
1275 (s->enc_read_ctx == NULL)) {
1276 al = SSL_AD_UNEXPECTED_MESSAGE;
1277 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_R_APP_DATA_IN_HANDSHAKE);
1278 goto f_err;
1279 }
1280
1281 if (len <= 0)
1282 return (len);
1283
1284 if ((unsigned int)len > rr->length)
1285 n = rr->length;
1286 else
1287 n = (unsigned int)len;
1288
1289 memcpy(buf, &(rr->data[rr->off]), n);
1290 if (!peek) {
1291 rr->length -= n;
1292 rr->off += n;
1293 if (rr->length == 0) {
1294 s->rstate = SSL_ST_READ_HEADER;
1295 rr->off = 0;
1296 if (s->mode & SSL_MODE_RELEASE_BUFFERS
1297 && s->s3->rbuf.left == 0)
1298 ssl3_release_read_buffer(s);
1299 }
1300 }
1301 return (n);
1302 }
1303
1304 /*
1305 * If we get here, then type != rr->type; if we have a handshake message,
1306 * then it was unexpected (Hello Request or Client Hello).
1307 */
1308
1309 /*
1310 * In case of record types for which we have 'fragment' storage, fill
1311 * that so that we can process the data at a fixed place.
1312 */
1313 {
1314 unsigned int dest_maxlen = 0;
1315 unsigned char *dest = NULL;
1316 unsigned int *dest_len = NULL;
1317
1318 if (rr->type == SSL3_RT_HANDSHAKE) {
1319 dest_maxlen = sizeof s->s3->handshake_fragment;
1320 dest = s->s3->handshake_fragment;
1321 dest_len = &s->s3->handshake_fragment_len;
1322 } else if (rr->type == SSL3_RT_ALERT) {
1323 dest_maxlen = sizeof s->s3->alert_fragment;
1324 dest = s->s3->alert_fragment;
1325 dest_len = &s->s3->alert_fragment_len;
1326 }
1327 #ifndef OPENSSL_NO_HEARTBEATS
1328 else if (rr->type == TLS1_RT_HEARTBEAT) {
1329 tls1_process_heartbeat(s);
1330
1331 /* Exit and notify application to read again */
1332 rr->length = 0;
1333 s->rwstate = SSL_READING;
1334 BIO_clear_retry_flags(SSL_get_rbio(s));
1335 BIO_set_retry_read(SSL_get_rbio(s));
1336 return (-1);
1337 }
1338 #endif
1339
1340 if (dest_maxlen > 0) {
1341 n = dest_maxlen - *dest_len; /* available space in 'dest' */
1342 if (rr->length < n)
1343 n = rr->length; /* available bytes */
1344
1345 /* now move 'n' bytes: */
1346 while (n-- > 0) {
1347 dest[(*dest_len)++] = rr->data[rr->off++];
1348 rr->length--;
1349 }
1350
1351 if (*dest_len < dest_maxlen)
1352 goto start; /* fragment was too small */
1353 }
1354 }
1355
1356 /*-
1357 * s->s3->handshake_fragment_len == 4 iff rr->type == SSL3_RT_HANDSHAKE;
1358 * s->s3->alert_fragment_len == 2 iff rr->type == SSL3_RT_ALERT.
1359 * (Possibly rr is 'empty' now, i.e. rr->length may be 0.)
1360 */
1361
1362 /* If we are a client, check for an incoming 'Hello Request': */
1363 if ((!s->server) &&
1364 (s->s3->handshake_fragment_len >= 4) &&
1365 (s->s3->handshake_fragment[0] == SSL3_MT_HELLO_REQUEST) &&
1366 (s->session != NULL) && (s->session->cipher != NULL)) {
1367 s->s3->handshake_fragment_len = 0;
1368
1369 if ((s->s3->handshake_fragment[1] != 0) ||
1370 (s->s3->handshake_fragment[2] != 0) ||
1371 (s->s3->handshake_fragment[3] != 0)) {
1372 al = SSL_AD_DECODE_ERROR;
1373 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_R_BAD_HELLO_REQUEST);
1374 goto f_err;
1375 }
1376
1377 if (s->msg_callback)
1378 s->msg_callback(0, s->version, SSL3_RT_HANDSHAKE,
1379 s->s3->handshake_fragment, 4, s,
1380 s->msg_callback_arg);
1381
1382 if (SSL_is_init_finished(s) &&
1383 !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS) &&
1384 !s->s3->renegotiate) {
1385 ssl3_renegotiate(s);
1386 if (ssl3_renegotiate_check(s)) {
1387 i = s->handshake_func(s);
1388 if (i < 0)
1389 return (i);
1390 if (i == 0) {
1391 SSLerr(SSL_F_SSL3_READ_BYTES,
1392 SSL_R_SSL_HANDSHAKE_FAILURE);
1393 return (-1);
1394 }
1395
1396 if (!(s->mode & SSL_MODE_AUTO_RETRY)) {
1397 if (s->s3->rbuf.left == 0) { /* no read-ahead left? */
1398 BIO *bio;
1399 /*
1400 * In the case where we try to read application data,
1401 * but we trigger an SSL handshake, we return -1 with
1402 * the retry option set. Otherwise renegotiation may
1403 * cause nasty problems in the blocking world
1404 */
1405 s->rwstate = SSL_READING;
1406 bio = SSL_get_rbio(s);
1407 BIO_clear_retry_flags(bio);
1408 BIO_set_retry_read(bio);
1409 return (-1);
1410 }
1411 }
1412 }
1413 }
1414 /*
1415 * we either finished a handshake or ignored the request, now try
1416 * again to obtain the (application) data we were asked for
1417 */
1418 goto start;
1419 }
1420 /*
1421 * If we are a server and get a client hello when renegotiation isn't
1422 * allowed send back a no renegotiation alert and carry on. WARNING:
1423 * experimental code, needs reviewing (steve)
1424 */
1425 if (s->server &&
1426 SSL_is_init_finished(s) &&
1427 !s->s3->send_connection_binding &&
1428 (s->version > SSL3_VERSION) &&
1429 (s->s3->handshake_fragment_len >= 4) &&
1430 (s->s3->handshake_fragment[0] == SSL3_MT_CLIENT_HELLO) &&
1431 (s->session != NULL) && (s->session->cipher != NULL) &&
1432 !(s->ctx->options & SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION)) {
1433 /*
1434 * s->s3->handshake_fragment_len = 0;
1435 */
1436 rr->length = 0;
1437 ssl3_send_alert(s, SSL3_AL_WARNING, SSL_AD_NO_RENEGOTIATION);
1438 goto start;
1439 }
1440 if (s->s3->alert_fragment_len >= 2) {
1441 int alert_level = s->s3->alert_fragment[0];
1442 int alert_descr = s->s3->alert_fragment[1];
1443
1444 s->s3->alert_fragment_len = 0;
1445
1446 if (s->msg_callback)
1447 s->msg_callback(0, s->version, SSL3_RT_ALERT,
1448 s->s3->alert_fragment, 2, s, s->msg_callback_arg);
1449
1450 if (s->info_callback != NULL)
1451 cb = s->info_callback;
1452 else if (s->ctx->info_callback != NULL)
1453 cb = s->ctx->info_callback;
1454
1455 if (cb != NULL) {
1456 j = (alert_level << 8) | alert_descr;
1457 cb(s, SSL_CB_READ_ALERT, j);
1458 }
1459
1460 if (alert_level == SSL3_AL_WARNING) {
1461 s->s3->warn_alert = alert_descr;
1462
1463 s->cert->alert_count++;
1464 if (s->cert->alert_count == MAX_WARN_ALERT_COUNT) {
1465 al = SSL_AD_UNEXPECTED_MESSAGE;
1466 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_R_TOO_MANY_WARN_ALERTS);
1467 goto f_err;
1468 }
1469
1470 if (alert_descr == SSL_AD_CLOSE_NOTIFY) {
1471 s->shutdown |= SSL_RECEIVED_SHUTDOWN;
1472 return (0);
1473 }
1474 /*
1475 * This is a warning but we receive it if we requested
1476 * renegotiation and the peer denied it. Terminate with a fatal
1477 * alert because if application tried to renegotiatie it
1478 * presumably had a good reason and expects it to succeed. In
1479 * future we might have a renegotiation where we don't care if
1480 * the peer refused it where we carry on.
1481 */
1482 else if (alert_descr == SSL_AD_NO_RENEGOTIATION) {
1483 al = SSL_AD_HANDSHAKE_FAILURE;
1484 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_R_NO_RENEGOTIATION);
1485 goto f_err;
1486 }
1487 #ifdef SSL_AD_MISSING_SRP_USERNAME
1488 else if (alert_descr == SSL_AD_MISSING_SRP_USERNAME)
1489 return (0);
1490 #endif
1491 } else if (alert_level == SSL3_AL_FATAL) {
1492 char tmp[16];
1493
1494 s->rwstate = SSL_NOTHING;
1495 s->s3->fatal_alert = alert_descr;
1496 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_AD_REASON_OFFSET + alert_descr);
1497 BIO_snprintf(tmp, sizeof tmp, "%d", alert_descr);
1498 ERR_add_error_data(2, "SSL alert number ", tmp);
1499 s->shutdown |= SSL_RECEIVED_SHUTDOWN;
1500 SSL_CTX_remove_session(s->session_ctx, s->session);
1501 return (0);
1502 } else {
1503 al = SSL_AD_ILLEGAL_PARAMETER;
1504 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_R_UNKNOWN_ALERT_TYPE);
1505 goto f_err;
1506 }
1507
1508 goto start;
1509 }
1510
1511 if (s->shutdown & SSL_SENT_SHUTDOWN) { /* but we have not received a
1512 * shutdown */
1513 s->rwstate = SSL_NOTHING;
1514 rr->length = 0;
1515 return (0);
1516 }
1517
1518 if (rr->type == SSL3_RT_CHANGE_CIPHER_SPEC) {
1519 /*
1520 * 'Change Cipher Spec' is just a single byte, so we know exactly
1521 * what the record payload has to look like
1522 */
1523 if ((rr->length != 1) || (rr->off != 0) ||
1524 (rr->data[0] != SSL3_MT_CCS)) {
1525 al = SSL_AD_ILLEGAL_PARAMETER;
1526 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_R_BAD_CHANGE_CIPHER_SPEC);
1527 goto f_err;
1528 }
1529
1530 /* Check we have a cipher to change to */
1531 if (s->s3->tmp.new_cipher == NULL) {
1532 al = SSL_AD_UNEXPECTED_MESSAGE;
1533 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_R_CCS_RECEIVED_EARLY);
1534 goto f_err;
1535 }
1536
1537 if (!(s->s3->flags & SSL3_FLAGS_CCS_OK)) {
1538 al = SSL_AD_UNEXPECTED_MESSAGE;
1539 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_R_CCS_RECEIVED_EARLY);
1540 goto f_err;
1541 }
1542
1543 s->s3->flags &= ~SSL3_FLAGS_CCS_OK;
1544
1545 rr->length = 0;
1546
1547 if (s->msg_callback)
1548 s->msg_callback(0, s->version, SSL3_RT_CHANGE_CIPHER_SPEC,
1549 rr->data, 1, s, s->msg_callback_arg);
1550
1551 s->s3->change_cipher_spec = 1;
1552 if (!ssl3_do_change_cipher_spec(s))
1553 goto err;
1554 else
1555 goto start;
1556 }
1557
1558 /*
1559 * Unexpected handshake message (Client Hello, or protocol violation)
1560 */
1561 if ((s->s3->handshake_fragment_len >= 4) && !s->in_handshake) {
1562 if (((s->state & SSL_ST_MASK) == SSL_ST_OK) &&
1563 !(s->s3->flags & SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS)) {
1564 #if 0 /* worked only because C operator preferences
1565 * are not as expected (and because this is
1566 * not really needed for clients except for
1567 * detecting protocol violations): */
1568 s->state = SSL_ST_BEFORE | (s->server)
1569 ? SSL_ST_ACCEPT : SSL_ST_CONNECT;
1570 #else
1571 s->state = s->server ? SSL_ST_ACCEPT : SSL_ST_CONNECT;
1572 #endif
1573 s->renegotiate = 1;
1574 s->new_session = 1;
1575 }
1576 i = s->handshake_func(s);
1577 if (i < 0)
1578 return (i);
1579 if (i == 0) {
1580 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_R_SSL_HANDSHAKE_FAILURE);
1581 return (-1);
1582 }
1583
1584 if (!(s->mode & SSL_MODE_AUTO_RETRY)) {
1585 if (s->s3->rbuf.left == 0) { /* no read-ahead left? */
1586 BIO *bio;
1587 /*
1588 * In the case where we try to read application data, but we
1589 * trigger an SSL handshake, we return -1 with the retry
1590 * option set. Otherwise renegotiation may cause nasty
1591 * problems in the blocking world
1592 */
1593 s->rwstate = SSL_READING;
1594 bio = SSL_get_rbio(s);
1595 BIO_clear_retry_flags(bio);
1596 BIO_set_retry_read(bio);
1597 return (-1);
1598 }
1599 }
1600 goto start;
1601 }
1602
1603 switch (rr->type) {
1604 default:
1605 /*
1606 * TLS 1.0 and 1.1 say you SHOULD ignore unrecognised record types, but
1607 * TLS 1.2 says you MUST send an unexpected message alert. We use the
1608 * TLS 1.2 behaviour for all protocol versions to prevent issues where
1609 * no progress is being made and the peer continually sends unrecognised
1610 * record types, using up resources processing them.
1611 */
1612 al = SSL_AD_UNEXPECTED_MESSAGE;
1613 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_R_UNEXPECTED_RECORD);
1614 goto f_err;
1615 case SSL3_RT_CHANGE_CIPHER_SPEC:
1616 case SSL3_RT_ALERT:
1617 case SSL3_RT_HANDSHAKE:
1618 /*
1619 * we already handled all of these, with the possible exception of
1620 * SSL3_RT_HANDSHAKE when s->in_handshake is set, but that should not
1621 * happen when type != rr->type
1622 */
1623 al = SSL_AD_UNEXPECTED_MESSAGE;
1624 SSLerr(SSL_F_SSL3_READ_BYTES, ERR_R_INTERNAL_ERROR);
1625 goto f_err;
1626 case SSL3_RT_APPLICATION_DATA:
1627 /*
1628 * At this point, we were expecting handshake data, but have
1629 * application data. If the library was running inside ssl3_read()
1630 * (i.e. in_read_app_data is set) and it makes sense to read
1631 * application data at this point (session renegotiation not yet
1632 * started), we will indulge it.
1633 */
1634 if (s->s3->in_read_app_data &&
1635 (s->s3->total_renegotiations != 0) &&
1636 (((s->state & SSL_ST_CONNECT) &&
1637 (s->state >= SSL3_ST_CW_CLNT_HELLO_A) &&
1638 (s->state <= SSL3_ST_CR_SRVR_HELLO_A)
1639 ) || ((s->state & SSL_ST_ACCEPT) &&
1640 (s->state <= SSL3_ST_SW_HELLO_REQ_A) &&
1641 (s->state >= SSL3_ST_SR_CLNT_HELLO_A)
1642 )
1643 )) {
1644 s->s3->in_read_app_data = 2;
1645 return (-1);
1646 } else {
1647 al = SSL_AD_UNEXPECTED_MESSAGE;
1648 SSLerr(SSL_F_SSL3_READ_BYTES, SSL_R_UNEXPECTED_RECORD);
1649 goto f_err;
1650 }
1651 }
1652 /* not reached */
1653
1654 f_err:
1655 ssl3_send_alert(s, SSL3_AL_FATAL, al);
1656 err:
1657 return (-1);
1658 }
1659
ssl3_do_change_cipher_spec(SSL * s)1660 int ssl3_do_change_cipher_spec(SSL *s)
1661 {
1662 int i;
1663 const char *sender;
1664 int slen;
1665
1666 if (s->state & SSL_ST_ACCEPT)
1667 i = SSL3_CHANGE_CIPHER_SERVER_READ;
1668 else
1669 i = SSL3_CHANGE_CIPHER_CLIENT_READ;
1670
1671 if (s->s3->tmp.key_block == NULL) {
1672 if (s->session == NULL || s->session->master_key_length == 0) {
1673 /* might happen if dtls1_read_bytes() calls this */
1674 SSLerr(SSL_F_SSL3_DO_CHANGE_CIPHER_SPEC,
1675 SSL_R_CCS_RECEIVED_EARLY);
1676 return (0);
1677 }
1678
1679 s->session->cipher = s->s3->tmp.new_cipher;
1680 if (!s->method->ssl3_enc->setup_key_block(s))
1681 return (0);
1682 }
1683
1684 if (!s->method->ssl3_enc->change_cipher_state(s, i))
1685 return (0);
1686
1687 /*
1688 * we have to record the message digest at this point so we can get it
1689 * before we read the finished message
1690 */
1691 if (s->state & SSL_ST_CONNECT) {
1692 sender = s->method->ssl3_enc->server_finished_label;
1693 slen = s->method->ssl3_enc->server_finished_label_len;
1694 } else {
1695 sender = s->method->ssl3_enc->client_finished_label;
1696 slen = s->method->ssl3_enc->client_finished_label_len;
1697 }
1698
1699 i = s->method->ssl3_enc->final_finish_mac(s,
1700 sender, slen,
1701 s->s3->tmp.peer_finish_md);
1702 if (i == 0) {
1703 SSLerr(SSL_F_SSL3_DO_CHANGE_CIPHER_SPEC, ERR_R_INTERNAL_ERROR);
1704 return 0;
1705 }
1706 s->s3->tmp.peer_finish_md_len = i;
1707
1708 return (1);
1709 }
1710
ssl3_send_alert(SSL * s,int level,int desc)1711 int ssl3_send_alert(SSL *s, int level, int desc)
1712 {
1713 /* Map tls/ssl alert value to correct one */
1714 desc = s->method->ssl3_enc->alert_value(desc);
1715 if (s->version == SSL3_VERSION && desc == SSL_AD_PROTOCOL_VERSION)
1716 desc = SSL_AD_HANDSHAKE_FAILURE; /* SSL 3.0 does not have
1717 * protocol_version alerts */
1718 if (desc < 0)
1719 return -1;
1720 /* If a fatal one, remove from cache */
1721 if ((level == 2) && (s->session != NULL))
1722 SSL_CTX_remove_session(s->session_ctx, s->session);
1723
1724 s->s3->alert_dispatch = 1;
1725 s->s3->send_alert[0] = level;
1726 s->s3->send_alert[1] = desc;
1727 if (s->s3->wbuf.left == 0) /* data still being written out? */
1728 return s->method->ssl_dispatch_alert(s);
1729 /*
1730 * else data is still being written out, we will get written some time in
1731 * the future
1732 */
1733 return -1;
1734 }
1735
ssl3_dispatch_alert(SSL * s)1736 int ssl3_dispatch_alert(SSL *s)
1737 {
1738 int i, j;
1739 void (*cb) (const SSL *ssl, int type, int val) = NULL;
1740
1741 s->s3->alert_dispatch = 0;
1742 i = do_ssl3_write(s, SSL3_RT_ALERT, &s->s3->send_alert[0], 2, 0);
1743 if (i <= 0) {
1744 s->s3->alert_dispatch = 1;
1745 } else {
1746 /*
1747 * Alert sent to BIO. If it is important, flush it now. If the
1748 * message does not get sent due to non-blocking IO, we will not
1749 * worry too much.
1750 */
1751 if (s->s3->send_alert[0] == SSL3_AL_FATAL)
1752 (void)BIO_flush(s->wbio);
1753
1754 if (s->msg_callback)
1755 s->msg_callback(1, s->version, SSL3_RT_ALERT, s->s3->send_alert,
1756 2, s, s->msg_callback_arg);
1757
1758 if (s->info_callback != NULL)
1759 cb = s->info_callback;
1760 else if (s->ctx->info_callback != NULL)
1761 cb = s->ctx->info_callback;
1762
1763 if (cb != NULL) {
1764 j = (s->s3->send_alert[0] << 8) | s->s3->send_alert[1];
1765 cb(s, SSL_CB_WRITE_ALERT, j);
1766 }
1767 }
1768 return (i);
1769 }
1770