1 /*
2 * Copyright 1995-2022 The OpenSSL Project Authors. All Rights Reserved.
3 *
4 * Licensed under the Apache License 2.0 (the "License"). You may not use
5 * this file except in compliance with the License. You can obtain a copy
6 * in the file LICENSE in the source distribution or at
7 * https://www.openssl.org/source/license.html
8 */
9
10 #include "../ssl_local.h"
11 #include <openssl/trace.h>
12 #include <openssl/rand.h>
13 #include <openssl/core_names.h>
14 #include "record_local.h"
15 #include "internal/cryptlib.h"
16
17 static const unsigned char ssl3_pad_1[48] = {
18 0x36, 0x36, 0x36, 0x36, 0x36, 0x36, 0x36, 0x36,
19 0x36, 0x36, 0x36, 0x36, 0x36, 0x36, 0x36, 0x36,
20 0x36, 0x36, 0x36, 0x36, 0x36, 0x36, 0x36, 0x36,
21 0x36, 0x36, 0x36, 0x36, 0x36, 0x36, 0x36, 0x36,
22 0x36, 0x36, 0x36, 0x36, 0x36, 0x36, 0x36, 0x36,
23 0x36, 0x36, 0x36, 0x36, 0x36, 0x36, 0x36, 0x36
24 };
25
26 static const unsigned char ssl3_pad_2[48] = {
27 0x5c, 0x5c, 0x5c, 0x5c, 0x5c, 0x5c, 0x5c, 0x5c,
28 0x5c, 0x5c, 0x5c, 0x5c, 0x5c, 0x5c, 0x5c, 0x5c,
29 0x5c, 0x5c, 0x5c, 0x5c, 0x5c, 0x5c, 0x5c, 0x5c,
30 0x5c, 0x5c, 0x5c, 0x5c, 0x5c, 0x5c, 0x5c, 0x5c,
31 0x5c, 0x5c, 0x5c, 0x5c, 0x5c, 0x5c, 0x5c, 0x5c,
32 0x5c, 0x5c, 0x5c, 0x5c, 0x5c, 0x5c, 0x5c, 0x5c
33 };
34
35 /*
36 * Clear the contents of an SSL3_RECORD but retain any memory allocated
37 */
SSL3_RECORD_clear(SSL3_RECORD * r,size_t num_recs)38 void SSL3_RECORD_clear(SSL3_RECORD *r, size_t num_recs)
39 {
40 unsigned char *comp;
41 size_t i;
42
43 for (i = 0; i < num_recs; i++) {
44 comp = r[i].comp;
45
46 memset(&r[i], 0, sizeof(*r));
47 r[i].comp = comp;
48 }
49 }
50
SSL3_RECORD_release(SSL3_RECORD * r,size_t num_recs)51 void SSL3_RECORD_release(SSL3_RECORD *r, size_t num_recs)
52 {
53 size_t i;
54
55 for (i = 0; i < num_recs; i++) {
56 OPENSSL_free(r[i].comp);
57 r[i].comp = NULL;
58 }
59 }
60
SSL3_RECORD_set_seq_num(SSL3_RECORD * r,const unsigned char * seq_num)61 void SSL3_RECORD_set_seq_num(SSL3_RECORD *r, const unsigned char *seq_num)
62 {
63 memcpy(r->seq_num, seq_num, SEQ_NUM_SIZE);
64 }
65
66 /*
67 * Peeks ahead into "read_ahead" data to see if we have a whole record waiting
68 * for us in the buffer.
69 */
ssl3_record_app_data_waiting(SSL * s)70 static int ssl3_record_app_data_waiting(SSL *s)
71 {
72 SSL3_BUFFER *rbuf;
73 size_t left, len;
74 unsigned char *p;
75
76 rbuf = RECORD_LAYER_get_rbuf(&s->rlayer);
77
78 p = SSL3_BUFFER_get_buf(rbuf);
79 if (p == NULL)
80 return 0;
81
82 left = SSL3_BUFFER_get_left(rbuf);
83
84 if (left < SSL3_RT_HEADER_LENGTH)
85 return 0;
86
87 p += SSL3_BUFFER_get_offset(rbuf);
88
89 /*
90 * We only check the type and record length, we will sanity check version
91 * etc later
92 */
93 if (*p != SSL3_RT_APPLICATION_DATA)
94 return 0;
95
96 p += 3;
97 n2s(p, len);
98
99 if (left < SSL3_RT_HEADER_LENGTH + len)
100 return 0;
101
102 return 1;
103 }
104
early_data_count_ok(SSL * s,size_t length,size_t overhead,int send)105 int early_data_count_ok(SSL *s, size_t length, size_t overhead, int send)
106 {
107 uint32_t max_early_data;
108 SSL_SESSION *sess = s->session;
109
110 /*
111 * If we are a client then we always use the max_early_data from the
112 * session/psksession. Otherwise we go with the lowest out of the max early
113 * data set in the session and the configured max_early_data.
114 */
115 if (!s->server && sess->ext.max_early_data == 0) {
116 if (!ossl_assert(s->psksession != NULL
117 && s->psksession->ext.max_early_data > 0)) {
118 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
119 return 0;
120 }
121 sess = s->psksession;
122 }
123
124 if (!s->server)
125 max_early_data = sess->ext.max_early_data;
126 else if (s->ext.early_data != SSL_EARLY_DATA_ACCEPTED)
127 max_early_data = s->recv_max_early_data;
128 else
129 max_early_data = s->recv_max_early_data < sess->ext.max_early_data
130 ? s->recv_max_early_data : sess->ext.max_early_data;
131
132 if (max_early_data == 0) {
133 SSLfatal(s, send ? SSL_AD_INTERNAL_ERROR : SSL_AD_UNEXPECTED_MESSAGE,
134 SSL_R_TOO_MUCH_EARLY_DATA);
135 return 0;
136 }
137
138 /* If we are dealing with ciphertext we need to allow for the overhead */
139 max_early_data += overhead;
140
141 if (s->early_data_count + length > max_early_data) {
142 SSLfatal(s, send ? SSL_AD_INTERNAL_ERROR : SSL_AD_UNEXPECTED_MESSAGE,
143 SSL_R_TOO_MUCH_EARLY_DATA);
144 return 0;
145 }
146 s->early_data_count += length;
147
148 return 1;
149 }
150
151 /*
152 * MAX_EMPTY_RECORDS defines the number of consecutive, empty records that
153 * will be processed per call to ssl3_get_record. Without this limit an
154 * attacker could send empty records at a faster rate than we can process and
155 * cause ssl3_get_record to loop forever.
156 */
157 #define MAX_EMPTY_RECORDS 32
158
159 #define SSL2_RT_HEADER_LENGTH 2
160 /*-
161 * Call this to get new input records.
162 * It will return <= 0 if more data is needed, normally due to an error
163 * or non-blocking IO.
164 * When it finishes, |numrpipes| records have been decoded. For each record 'i':
165 * rr[i].type - is the type of record
166 * rr[i].data, - data
167 * rr[i].length, - number of bytes
168 * Multiple records will only be returned if the record types are all
169 * SSL3_RT_APPLICATION_DATA. The number of records returned will always be <=
170 * |max_pipelines|
171 */
172 /* used only by ssl3_read_bytes */
ssl3_get_record(SSL * s)173 int ssl3_get_record(SSL *s)
174 {
175 int enc_err, rret;
176 int i;
177 size_t more, n;
178 SSL3_RECORD *rr, *thisrr;
179 SSL3_BUFFER *rbuf;
180 SSL_SESSION *sess;
181 unsigned char *p;
182 unsigned char md[EVP_MAX_MD_SIZE];
183 unsigned int version;
184 size_t mac_size = 0;
185 int imac_size;
186 size_t num_recs = 0, max_recs, j;
187 PACKET pkt, sslv2pkt;
188 int is_ktls_left;
189 SSL_MAC_BUF *macbufs = NULL;
190 int ret = -1;
191
192 rr = RECORD_LAYER_get_rrec(&s->rlayer);
193 rbuf = RECORD_LAYER_get_rbuf(&s->rlayer);
194 is_ktls_left = (SSL3_BUFFER_get_left(rbuf) > 0);
195 max_recs = s->max_pipelines;
196 if (max_recs == 0)
197 max_recs = 1;
198 sess = s->session;
199
200 do {
201 thisrr = &rr[num_recs];
202
203 /* check if we have the header */
204 if ((RECORD_LAYER_get_rstate(&s->rlayer) != SSL_ST_READ_BODY) ||
205 (RECORD_LAYER_get_packet_length(&s->rlayer)
206 < SSL3_RT_HEADER_LENGTH)) {
207 size_t sslv2len;
208 unsigned int type;
209
210 rret = ssl3_read_n(s, SSL3_RT_HEADER_LENGTH,
211 SSL3_BUFFER_get_len(rbuf), 0,
212 num_recs == 0 ? 1 : 0, &n);
213 if (rret <= 0) {
214 #ifndef OPENSSL_NO_KTLS
215 if (!BIO_get_ktls_recv(s->rbio) || rret == 0)
216 return rret; /* error or non-blocking */
217 switch (errno) {
218 case EBADMSG:
219 SSLfatal(s, SSL_AD_BAD_RECORD_MAC,
220 SSL_R_DECRYPTION_FAILED_OR_BAD_RECORD_MAC);
221 break;
222 case EMSGSIZE:
223 SSLfatal(s, SSL_AD_RECORD_OVERFLOW,
224 SSL_R_PACKET_LENGTH_TOO_LONG);
225 break;
226 case EINVAL:
227 SSLfatal(s, SSL_AD_PROTOCOL_VERSION,
228 SSL_R_WRONG_VERSION_NUMBER);
229 break;
230 default:
231 break;
232 }
233 #endif
234 return rret;
235 }
236 RECORD_LAYER_set_rstate(&s->rlayer, SSL_ST_READ_BODY);
237
238 p = RECORD_LAYER_get_packet(&s->rlayer);
239 if (!PACKET_buf_init(&pkt, RECORD_LAYER_get_packet(&s->rlayer),
240 RECORD_LAYER_get_packet_length(&s->rlayer))) {
241 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
242 return -1;
243 }
244 sslv2pkt = pkt;
245 if (!PACKET_get_net_2_len(&sslv2pkt, &sslv2len)
246 || !PACKET_get_1(&sslv2pkt, &type)) {
247 SSLfatal(s, SSL_AD_DECODE_ERROR, ERR_R_INTERNAL_ERROR);
248 return -1;
249 }
250 /*
251 * The first record received by the server may be a V2ClientHello.
252 */
253 if (s->server && RECORD_LAYER_is_first_record(&s->rlayer)
254 && (sslv2len & 0x8000) != 0
255 && (type == SSL2_MT_CLIENT_HELLO)) {
256 /*
257 * SSLv2 style record
258 *
259 * |num_recs| here will actually always be 0 because
260 * |num_recs > 0| only ever occurs when we are processing
261 * multiple app data records - which we know isn't the case here
262 * because it is an SSLv2ClientHello. We keep it using
263 * |num_recs| for the sake of consistency
264 */
265 thisrr->type = SSL3_RT_HANDSHAKE;
266 thisrr->rec_version = SSL2_VERSION;
267
268 thisrr->length = sslv2len & 0x7fff;
269
270 if (thisrr->length > SSL3_BUFFER_get_len(rbuf)
271 - SSL2_RT_HEADER_LENGTH) {
272 SSLfatal(s, SSL_AD_RECORD_OVERFLOW,
273 SSL_R_PACKET_LENGTH_TOO_LONG);
274 return -1;
275 }
276
277 if (thisrr->length < MIN_SSL2_RECORD_LEN) {
278 SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_TOO_SHORT);
279 return -1;
280 }
281 } else {
282 /* SSLv3+ style record */
283
284 /* Pull apart the header into the SSL3_RECORD */
285 if (!PACKET_get_1(&pkt, &type)
286 || !PACKET_get_net_2(&pkt, &version)
287 || !PACKET_get_net_2_len(&pkt, &thisrr->length)) {
288 if (s->msg_callback)
289 s->msg_callback(0, 0, SSL3_RT_HEADER, p, 5, s,
290 s->msg_callback_arg);
291 SSLfatal(s, SSL_AD_DECODE_ERROR, ERR_R_INTERNAL_ERROR);
292 return -1;
293 }
294 thisrr->type = type;
295 thisrr->rec_version = version;
296
297 if (s->msg_callback)
298 s->msg_callback(0, version, SSL3_RT_HEADER, p, 5, s,
299 s->msg_callback_arg);
300
301 /*
302 * Lets check version. In TLSv1.3 we only check this field
303 * when encryption is occurring (see later check). For the
304 * ServerHello after an HRR we haven't actually selected TLSv1.3
305 * yet, but we still treat it as TLSv1.3, so we must check for
306 * that explicitly
307 */
308 if (!s->first_packet && !SSL_IS_TLS13(s)
309 && s->hello_retry_request != SSL_HRR_PENDING
310 && version != (unsigned int)s->version) {
311 if ((s->version & 0xFF00) == (version & 0xFF00)
312 && !s->enc_write_ctx && !s->write_hash) {
313 if (thisrr->type == SSL3_RT_ALERT) {
314 /*
315 * The record is using an incorrect version number,
316 * but what we've got appears to be an alert. We
317 * haven't read the body yet to check whether its a
318 * fatal or not - but chances are it is. We probably
319 * shouldn't send a fatal alert back. We'll just
320 * end.
321 */
322 SSLfatal(s, SSL_AD_NO_ALERT,
323 SSL_R_WRONG_VERSION_NUMBER);
324 return -1;
325 }
326 /*
327 * Send back error using their minor version number :-)
328 */
329 s->version = (unsigned short)version;
330 }
331 SSLfatal(s, SSL_AD_PROTOCOL_VERSION,
332 SSL_R_WRONG_VERSION_NUMBER);
333 return -1;
334 }
335
336 if ((version >> 8) != SSL3_VERSION_MAJOR) {
337 if (RECORD_LAYER_is_first_record(&s->rlayer)) {
338 /* Go back to start of packet, look at the five bytes
339 * that we have. */
340 p = RECORD_LAYER_get_packet(&s->rlayer);
341 if (strncmp((char *)p, "GET ", 4) == 0 ||
342 strncmp((char *)p, "POST ", 5) == 0 ||
343 strncmp((char *)p, "HEAD ", 5) == 0 ||
344 strncmp((char *)p, "PUT ", 4) == 0) {
345 SSLfatal(s, SSL_AD_NO_ALERT, SSL_R_HTTP_REQUEST);
346 return -1;
347 } else if (strncmp((char *)p, "CONNE", 5) == 0) {
348 SSLfatal(s, SSL_AD_NO_ALERT,
349 SSL_R_HTTPS_PROXY_REQUEST);
350 return -1;
351 }
352
353 /* Doesn't look like TLS - don't send an alert */
354 SSLfatal(s, SSL_AD_NO_ALERT,
355 SSL_R_WRONG_VERSION_NUMBER);
356 return -1;
357 } else {
358 SSLfatal(s, SSL_AD_PROTOCOL_VERSION,
359 SSL_R_WRONG_VERSION_NUMBER);
360 return -1;
361 }
362 }
363
364 if (SSL_IS_TLS13(s) && s->enc_read_ctx != NULL) {
365 if (thisrr->type != SSL3_RT_APPLICATION_DATA
366 && (thisrr->type != SSL3_RT_CHANGE_CIPHER_SPEC
367 || !SSL_IS_FIRST_HANDSHAKE(s))
368 && (thisrr->type != SSL3_RT_ALERT
369 || s->statem.enc_read_state
370 != ENC_READ_STATE_ALLOW_PLAIN_ALERTS)) {
371 SSLfatal(s, SSL_AD_UNEXPECTED_MESSAGE,
372 SSL_R_BAD_RECORD_TYPE);
373 return -1;
374 }
375 if (thisrr->rec_version != TLS1_2_VERSION) {
376 SSLfatal(s, SSL_AD_DECODE_ERROR,
377 SSL_R_WRONG_VERSION_NUMBER);
378 return -1;
379 }
380 }
381
382 if (thisrr->length >
383 SSL3_BUFFER_get_len(rbuf) - SSL3_RT_HEADER_LENGTH) {
384 SSLfatal(s, SSL_AD_RECORD_OVERFLOW,
385 SSL_R_PACKET_LENGTH_TOO_LONG);
386 return -1;
387 }
388 }
389
390 /* now s->rlayer.rstate == SSL_ST_READ_BODY */
391 }
392
393 if (SSL_IS_TLS13(s)) {
394 if (thisrr->length > SSL3_RT_MAX_TLS13_ENCRYPTED_LENGTH) {
395 SSLfatal(s, SSL_AD_RECORD_OVERFLOW,
396 SSL_R_ENCRYPTED_LENGTH_TOO_LONG);
397 return -1;
398 }
399 } else {
400 size_t len = SSL3_RT_MAX_ENCRYPTED_LENGTH;
401
402 #ifndef OPENSSL_NO_COMP
403 /*
404 * If OPENSSL_NO_COMP is defined then SSL3_RT_MAX_ENCRYPTED_LENGTH
405 * does not include the compression overhead anyway.
406 */
407 if (s->expand == NULL)
408 len -= SSL3_RT_MAX_COMPRESSED_OVERHEAD;
409 #endif
410
411 /* KTLS may use all of the buffer */
412 if (BIO_get_ktls_recv(s->rbio) && !is_ktls_left)
413 len = SSL3_BUFFER_get_left(rbuf);
414
415 if (thisrr->length > len) {
416 SSLfatal(s, SSL_AD_RECORD_OVERFLOW,
417 SSL_R_ENCRYPTED_LENGTH_TOO_LONG);
418 return -1;
419 }
420 }
421
422 /*
423 * s->rlayer.rstate == SSL_ST_READ_BODY, get and decode the data.
424 * Calculate how much more data we need to read for the rest of the
425 * record
426 */
427 if (thisrr->rec_version == SSL2_VERSION) {
428 more = thisrr->length + SSL2_RT_HEADER_LENGTH
429 - SSL3_RT_HEADER_LENGTH;
430 } else {
431 more = thisrr->length;
432 }
433
434 if (more > 0) {
435 /* now s->rlayer.packet_length == SSL3_RT_HEADER_LENGTH */
436
437 rret = ssl3_read_n(s, more, more, 1, 0, &n);
438 if (rret <= 0)
439 return rret; /* error or non-blocking io */
440 }
441
442 /* set state for later operations */
443 RECORD_LAYER_set_rstate(&s->rlayer, SSL_ST_READ_HEADER);
444
445 /*
446 * At this point, s->rlayer.packet_length == SSL3_RT_HEADER_LENGTH
447 * + thisrr->length, or s->rlayer.packet_length == SSL2_RT_HEADER_LENGTH
448 * + thisrr->length and we have that many bytes in s->rlayer.packet
449 */
450 if (thisrr->rec_version == SSL2_VERSION) {
451 thisrr->input =
452 &(RECORD_LAYER_get_packet(&s->rlayer)[SSL2_RT_HEADER_LENGTH]);
453 } else {
454 thisrr->input =
455 &(RECORD_LAYER_get_packet(&s->rlayer)[SSL3_RT_HEADER_LENGTH]);
456 }
457
458 /*
459 * ok, we can now read from 's->rlayer.packet' data into 'thisrr'.
460 * thisrr->input points at thisrr->length bytes, which need to be copied
461 * into thisrr->data by either the decryption or by the decompression.
462 * When the data is 'copied' into the thisrr->data buffer,
463 * thisrr->input will be updated to point at the new buffer
464 */
465
466 /*
467 * We now have - encrypted [ MAC [ compressed [ plain ] ] ]
468 * thisrr->length bytes of encrypted compressed stuff.
469 */
470
471 /* decrypt in place in 'thisrr->input' */
472 thisrr->data = thisrr->input;
473 thisrr->orig_len = thisrr->length;
474
475 /* Mark this record as not read by upper layers yet */
476 thisrr->read = 0;
477
478 num_recs++;
479
480 /* we have pulled in a full packet so zero things */
481 RECORD_LAYER_reset_packet_length(&s->rlayer);
482 RECORD_LAYER_clear_first_record(&s->rlayer);
483 } while (num_recs < max_recs
484 && thisrr->type == SSL3_RT_APPLICATION_DATA
485 && SSL_USE_EXPLICIT_IV(s)
486 && s->enc_read_ctx != NULL
487 && (EVP_CIPHER_get_flags(EVP_CIPHER_CTX_get0_cipher(s->enc_read_ctx))
488 & EVP_CIPH_FLAG_PIPELINE) != 0
489 && ssl3_record_app_data_waiting(s));
490
491 if (num_recs == 1
492 && thisrr->type == SSL3_RT_CHANGE_CIPHER_SPEC
493 && (SSL_IS_TLS13(s) || s->hello_retry_request != SSL_HRR_NONE)
494 && SSL_IS_FIRST_HANDSHAKE(s)) {
495 /*
496 * CCS messages must be exactly 1 byte long, containing the value 0x01
497 */
498 if (thisrr->length != 1 || thisrr->data[0] != 0x01) {
499 SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER,
500 SSL_R_INVALID_CCS_MESSAGE);
501 return -1;
502 }
503 /*
504 * CCS messages are ignored in TLSv1.3. We treat it like an empty
505 * handshake record
506 */
507 thisrr->type = SSL3_RT_HANDSHAKE;
508 RECORD_LAYER_inc_empty_record_count(&s->rlayer);
509 if (RECORD_LAYER_get_empty_record_count(&s->rlayer)
510 > MAX_EMPTY_RECORDS) {
511 SSLfatal(s, SSL_AD_UNEXPECTED_MESSAGE,
512 SSL_R_UNEXPECTED_CCS_MESSAGE);
513 return -1;
514 }
515 thisrr->read = 1;
516 RECORD_LAYER_set_numrpipes(&s->rlayer, 1);
517
518 return 1;
519 }
520
521 /*
522 * KTLS reads full records. If there is any data left,
523 * then it is from before enabling ktls
524 */
525 if (BIO_get_ktls_recv(s->rbio) && !is_ktls_left)
526 goto skip_decryption;
527
528 if (s->read_hash != NULL) {
529 const EVP_MD *tmpmd = EVP_MD_CTX_get0_md(s->read_hash);
530
531 if (tmpmd != NULL) {
532 imac_size = EVP_MD_get_size(tmpmd);
533 if (!ossl_assert(imac_size >= 0 && imac_size <= EVP_MAX_MD_SIZE)) {
534 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_EVP_LIB);
535 return -1;
536 }
537 mac_size = (size_t)imac_size;
538 }
539 }
540
541 /*
542 * If in encrypt-then-mac mode calculate mac from encrypted record. All
543 * the details below are public so no timing details can leak.
544 */
545 if (SSL_READ_ETM(s) && s->read_hash) {
546 unsigned char *mac;
547
548 for (j = 0; j < num_recs; j++) {
549 thisrr = &rr[j];
550
551 if (thisrr->length < mac_size) {
552 SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_TOO_SHORT);
553 return -1;
554 }
555 thisrr->length -= mac_size;
556 mac = thisrr->data + thisrr->length;
557 i = s->method->ssl3_enc->mac(s, thisrr, md, 0 /* not send */ );
558 if (i == 0 || CRYPTO_memcmp(md, mac, mac_size) != 0) {
559 SSLfatal(s, SSL_AD_BAD_RECORD_MAC,
560 SSL_R_DECRYPTION_FAILED_OR_BAD_RECORD_MAC);
561 return -1;
562 }
563 }
564 /*
565 * We've handled the mac now - there is no MAC inside the encrypted
566 * record
567 */
568 mac_size = 0;
569 }
570
571 if (mac_size > 0) {
572 macbufs = OPENSSL_zalloc(sizeof(*macbufs) * num_recs);
573 if (macbufs == NULL) {
574 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_MALLOC_FAILURE);
575 return -1;
576 }
577 }
578
579 enc_err = s->method->ssl3_enc->enc(s, rr, num_recs, 0, macbufs, mac_size);
580
581 /*-
582 * enc_err is:
583 * 0: if the record is publicly invalid, or an internal error, or AEAD
584 * decryption failed, or ETM decryption failed.
585 * 1: Success or MTE decryption failed (MAC will be randomised)
586 */
587 if (enc_err == 0) {
588 if (ossl_statem_in_error(s)) {
589 /* SSLfatal() already got called */
590 goto end;
591 }
592 if (num_recs == 1 && ossl_statem_skip_early_data(s)) {
593 /*
594 * Valid early_data that we cannot decrypt will fail here. We treat
595 * it like an empty record.
596 */
597
598 thisrr = &rr[0];
599
600 if (!early_data_count_ok(s, thisrr->length,
601 EARLY_DATA_CIPHERTEXT_OVERHEAD, 0)) {
602 /* SSLfatal() already called */
603 goto end;
604 }
605
606 thisrr->length = 0;
607 thisrr->read = 1;
608 RECORD_LAYER_set_numrpipes(&s->rlayer, 1);
609 RECORD_LAYER_reset_read_sequence(&s->rlayer);
610 ret = 1;
611 goto end;
612 }
613 SSLfatal(s, SSL_AD_BAD_RECORD_MAC,
614 SSL_R_DECRYPTION_FAILED_OR_BAD_RECORD_MAC);
615 goto end;
616 }
617 OSSL_TRACE_BEGIN(TLS) {
618 BIO_printf(trc_out, "dec %lu\n", (unsigned long)rr[0].length);
619 BIO_dump_indent(trc_out, rr[0].data, rr[0].length, 4);
620 } OSSL_TRACE_END(TLS);
621
622 /* r->length is now the compressed data plus mac */
623 if ((sess != NULL)
624 && (s->enc_read_ctx != NULL)
625 && (!SSL_READ_ETM(s) && EVP_MD_CTX_get0_md(s->read_hash) != NULL)) {
626 /* s->read_hash != NULL => mac_size != -1 */
627
628 for (j = 0; j < num_recs; j++) {
629 SSL_MAC_BUF *thismb = &macbufs[j];
630 thisrr = &rr[j];
631
632 i = s->method->ssl3_enc->mac(s, thisrr, md, 0 /* not send */ );
633 if (i == 0 || thismb == NULL || thismb->mac == NULL
634 || CRYPTO_memcmp(md, thismb->mac, (size_t)mac_size) != 0)
635 enc_err = 0;
636 if (thisrr->length > SSL3_RT_MAX_COMPRESSED_LENGTH + mac_size)
637 enc_err = 0;
638 }
639 }
640
641 if (enc_err == 0) {
642 if (ossl_statem_in_error(s)) {
643 /* We already called SSLfatal() */
644 goto end;
645 }
646 /*
647 * A separate 'decryption_failed' alert was introduced with TLS 1.0,
648 * SSL 3.0 only has 'bad_record_mac'. But unless a decryption
649 * failure is directly visible from the ciphertext anyway, we should
650 * not reveal which kind of error occurred -- this might become
651 * visible to an attacker (e.g. via a logfile)
652 */
653 SSLfatal(s, SSL_AD_BAD_RECORD_MAC,
654 SSL_R_DECRYPTION_FAILED_OR_BAD_RECORD_MAC);
655 goto end;
656 }
657
658 skip_decryption:
659
660 for (j = 0; j < num_recs; j++) {
661 thisrr = &rr[j];
662
663 /* thisrr->length is now just compressed */
664 if (s->expand != NULL) {
665 if (thisrr->length > SSL3_RT_MAX_COMPRESSED_LENGTH) {
666 SSLfatal(s, SSL_AD_RECORD_OVERFLOW,
667 SSL_R_COMPRESSED_LENGTH_TOO_LONG);
668 goto end;
669 }
670 if (!ssl3_do_uncompress(s, thisrr)) {
671 SSLfatal(s, SSL_AD_DECOMPRESSION_FAILURE,
672 SSL_R_BAD_DECOMPRESSION);
673 goto end;
674 }
675 }
676
677 if (SSL_IS_TLS13(s)
678 && s->enc_read_ctx != NULL
679 && thisrr->type != SSL3_RT_ALERT) {
680 size_t end;
681
682 if (thisrr->length == 0
683 || thisrr->type != SSL3_RT_APPLICATION_DATA) {
684 SSLfatal(s, SSL_AD_UNEXPECTED_MESSAGE, SSL_R_BAD_RECORD_TYPE);
685 goto end;
686 }
687
688 /* Strip trailing padding */
689 for (end = thisrr->length - 1; end > 0 && thisrr->data[end] == 0;
690 end--)
691 continue;
692
693 thisrr->length = end;
694 thisrr->type = thisrr->data[end];
695 if (thisrr->type != SSL3_RT_APPLICATION_DATA
696 && thisrr->type != SSL3_RT_ALERT
697 && thisrr->type != SSL3_RT_HANDSHAKE) {
698 SSLfatal(s, SSL_AD_UNEXPECTED_MESSAGE, SSL_R_BAD_RECORD_TYPE);
699 goto end;
700 }
701 if (s->msg_callback)
702 s->msg_callback(0, s->version, SSL3_RT_INNER_CONTENT_TYPE,
703 &thisrr->data[end], 1, s, s->msg_callback_arg);
704 }
705
706 /*
707 * TLSv1.3 alert and handshake records are required to be non-zero in
708 * length.
709 */
710 if (SSL_IS_TLS13(s)
711 && (thisrr->type == SSL3_RT_HANDSHAKE
712 || thisrr->type == SSL3_RT_ALERT)
713 && thisrr->length == 0) {
714 SSLfatal(s, SSL_AD_UNEXPECTED_MESSAGE, SSL_R_BAD_LENGTH);
715 goto end;
716 }
717
718 /*
719 * Usually thisrr->length is the length of a single record, but when
720 * KTLS handles the decryption, thisrr->length may be larger than
721 * SSL3_RT_MAX_PLAIN_LENGTH because the kernel may have coalesced
722 * multiple records.
723 * Therefore we have to rely on KTLS to check the plaintext length
724 * limit in the kernel.
725 */
726 if (thisrr->length > SSL3_RT_MAX_PLAIN_LENGTH
727 && (!BIO_get_ktls_recv(s->rbio) || is_ktls_left)) {
728 SSLfatal(s, SSL_AD_RECORD_OVERFLOW, SSL_R_DATA_LENGTH_TOO_LONG);
729 goto end;
730 }
731
732 /*
733 * Check if the received packet overflows the current
734 * Max Fragment Length setting.
735 * Note: USE_MAX_FRAGMENT_LENGTH_EXT and KTLS are mutually exclusive.
736 */
737 if (s->session != NULL && USE_MAX_FRAGMENT_LENGTH_EXT(s->session)
738 && thisrr->length > GET_MAX_FRAGMENT_LENGTH(s->session)) {
739 SSLfatal(s, SSL_AD_RECORD_OVERFLOW, SSL_R_DATA_LENGTH_TOO_LONG);
740 goto end;
741 }
742
743 thisrr->off = 0;
744 /*-
745 * So at this point the following is true
746 * thisrr->type is the type of record
747 * thisrr->length == number of bytes in record
748 * thisrr->off == offset to first valid byte
749 * thisrr->data == where to take bytes from, increment after use :-).
750 */
751
752 /* just read a 0 length packet */
753 if (thisrr->length == 0) {
754 RECORD_LAYER_inc_empty_record_count(&s->rlayer);
755 if (RECORD_LAYER_get_empty_record_count(&s->rlayer)
756 > MAX_EMPTY_RECORDS) {
757 SSLfatal(s, SSL_AD_UNEXPECTED_MESSAGE, SSL_R_RECORD_TOO_SMALL);
758 goto end;
759 }
760 } else {
761 RECORD_LAYER_reset_empty_record_count(&s->rlayer);
762 }
763 }
764
765 if (s->early_data_state == SSL_EARLY_DATA_READING) {
766 thisrr = &rr[0];
767 if (thisrr->type == SSL3_RT_APPLICATION_DATA
768 && !early_data_count_ok(s, thisrr->length, 0, 0)) {
769 /* SSLfatal already called */
770 goto end;
771 }
772 }
773
774 RECORD_LAYER_set_numrpipes(&s->rlayer, num_recs);
775 ret = 1;
776 end:
777 if (macbufs != NULL) {
778 for (j = 0; j < num_recs; j++) {
779 if (macbufs[j].alloced)
780 OPENSSL_free(macbufs[j].mac);
781 }
782 OPENSSL_free(macbufs);
783 }
784 return ret;
785 }
786
ssl3_do_uncompress(SSL * ssl,SSL3_RECORD * rr)787 int ssl3_do_uncompress(SSL *ssl, SSL3_RECORD *rr)
788 {
789 #ifndef OPENSSL_NO_COMP
790 int i;
791
792 if (rr->comp == NULL) {
793 rr->comp = (unsigned char *)
794 OPENSSL_malloc(SSL3_RT_MAX_ENCRYPTED_LENGTH);
795 }
796 if (rr->comp == NULL)
797 return 0;
798
799 i = COMP_expand_block(ssl->expand, rr->comp,
800 SSL3_RT_MAX_PLAIN_LENGTH, rr->data, (int)rr->length);
801 if (i < 0)
802 return 0;
803 else
804 rr->length = i;
805 rr->data = rr->comp;
806 #endif
807 return 1;
808 }
809
ssl3_do_compress(SSL * ssl,SSL3_RECORD * wr)810 int ssl3_do_compress(SSL *ssl, SSL3_RECORD *wr)
811 {
812 #ifndef OPENSSL_NO_COMP
813 int i;
814
815 i = COMP_compress_block(ssl->compress, wr->data,
816 (int)(wr->length + SSL3_RT_MAX_COMPRESSED_OVERHEAD),
817 wr->input, (int)wr->length);
818 if (i < 0)
819 return 0;
820 else
821 wr->length = i;
822
823 wr->input = wr->data;
824 #endif
825 return 1;
826 }
827
828 /*-
829 * ssl3_enc encrypts/decrypts |n_recs| records in |inrecs|. Calls SSLfatal on
830 * internal error, but not otherwise. It is the responsibility of the caller to
831 * report a bad_record_mac
832 *
833 * Returns:
834 * 0: if the record is publicly invalid, or an internal error
835 * 1: Success or Mac-then-encrypt decryption failed (MAC will be randomised)
836 */
ssl3_enc(SSL * s,SSL3_RECORD * inrecs,size_t n_recs,int sending,SSL_MAC_BUF * mac,size_t macsize)837 int ssl3_enc(SSL *s, SSL3_RECORD *inrecs, size_t n_recs, int sending,
838 SSL_MAC_BUF *mac, size_t macsize)
839 {
840 SSL3_RECORD *rec;
841 EVP_CIPHER_CTX *ds;
842 size_t l, i;
843 size_t bs;
844 const EVP_CIPHER *enc;
845
846 rec = inrecs;
847 /*
848 * We shouldn't ever be called with more than one record in the SSLv3 case
849 */
850 if (n_recs != 1)
851 return 0;
852 if (sending) {
853 ds = s->enc_write_ctx;
854 if (s->enc_write_ctx == NULL)
855 enc = NULL;
856 else
857 enc = EVP_CIPHER_CTX_get0_cipher(s->enc_write_ctx);
858 } else {
859 ds = s->enc_read_ctx;
860 if (s->enc_read_ctx == NULL)
861 enc = NULL;
862 else
863 enc = EVP_CIPHER_CTX_get0_cipher(s->enc_read_ctx);
864 }
865
866 if ((s->session == NULL) || (ds == NULL) || (enc == NULL)) {
867 memmove(rec->data, rec->input, rec->length);
868 rec->input = rec->data;
869 } else {
870 int provided = (EVP_CIPHER_get0_provider(enc) != NULL);
871
872 l = rec->length;
873 bs = EVP_CIPHER_CTX_get_block_size(ds);
874
875 /* COMPRESS */
876
877 if ((bs != 1) && sending && !provided) {
878 /*
879 * We only do this for legacy ciphers. Provided ciphers add the
880 * padding on the provider side.
881 */
882 i = bs - (l % bs);
883
884 /* we need to add 'i-1' padding bytes */
885 l += i;
886 /*
887 * the last of these zero bytes will be overwritten with the
888 * padding length.
889 */
890 memset(&rec->input[rec->length], 0, i);
891 rec->length += i;
892 rec->input[l - 1] = (unsigned char)(i - 1);
893 }
894
895 if (!sending) {
896 if (l == 0 || l % bs != 0) {
897 /* Publicly invalid */
898 return 0;
899 }
900 /* otherwise, rec->length >= bs */
901 }
902
903 if (EVP_CIPHER_get0_provider(enc) != NULL) {
904 int outlen;
905
906 if (!EVP_CipherUpdate(ds, rec->data, &outlen, rec->input,
907 (unsigned int)l))
908 return 0;
909 rec->length = outlen;
910
911 if (!sending && mac != NULL) {
912 /* Now get a pointer to the MAC */
913 OSSL_PARAM params[2], *p = params;
914
915 /* Get the MAC */
916 mac->alloced = 0;
917
918 *p++ = OSSL_PARAM_construct_octet_ptr(OSSL_CIPHER_PARAM_TLS_MAC,
919 (void **)&mac->mac,
920 macsize);
921 *p = OSSL_PARAM_construct_end();
922
923 if (!EVP_CIPHER_CTX_get_params(ds, params)) {
924 /* Shouldn't normally happen */
925 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
926 return 0;
927 }
928 }
929 } else {
930 if (EVP_Cipher(ds, rec->data, rec->input, (unsigned int)l) < 1) {
931 /* Shouldn't happen */
932 SSLfatal(s, SSL_AD_BAD_RECORD_MAC, ERR_R_INTERNAL_ERROR);
933 return 0;
934 }
935
936 if (!sending)
937 return ssl3_cbc_remove_padding_and_mac(&rec->length,
938 rec->orig_len,
939 rec->data,
940 (mac != NULL) ? &mac->mac : NULL,
941 (mac != NULL) ? &mac->alloced : NULL,
942 bs,
943 macsize,
944 s->ctx->libctx);
945 }
946 }
947 return 1;
948 }
949
950 #define MAX_PADDING 256
951 /*-
952 * tls1_enc encrypts/decrypts |n_recs| in |recs|. Calls SSLfatal on internal
953 * error, but not otherwise. It is the responsibility of the caller to report
954 * a bad_record_mac - if appropriate (DTLS just drops the record).
955 *
956 * Returns:
957 * 0: if the record is publicly invalid, or an internal error, or AEAD
958 * decryption failed, or Encrypt-then-mac decryption failed.
959 * 1: Success or Mac-then-encrypt decryption failed (MAC will be randomised)
960 */
tls1_enc(SSL * s,SSL3_RECORD * recs,size_t n_recs,int sending,SSL_MAC_BUF * macs,size_t macsize)961 int tls1_enc(SSL *s, SSL3_RECORD *recs, size_t n_recs, int sending,
962 SSL_MAC_BUF *macs, size_t macsize)
963 {
964 EVP_CIPHER_CTX *ds;
965 size_t reclen[SSL_MAX_PIPELINES];
966 unsigned char buf[SSL_MAX_PIPELINES][EVP_AEAD_TLS1_AAD_LEN];
967 int i, pad = 0, tmpr;
968 size_t bs, ctr, padnum, loop;
969 unsigned char padval;
970 const EVP_CIPHER *enc;
971 int tlstree_enc = sending ? (s->mac_flags & SSL_MAC_FLAG_WRITE_MAC_TLSTREE)
972 : (s->mac_flags & SSL_MAC_FLAG_READ_MAC_TLSTREE);
973
974 if (n_recs == 0) {
975 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
976 return 0;
977 }
978
979 if (sending) {
980 if (EVP_MD_CTX_get0_md(s->write_hash)) {
981 int n = EVP_MD_CTX_get_size(s->write_hash);
982 if (!ossl_assert(n >= 0)) {
983 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
984 return 0;
985 }
986 }
987 ds = s->enc_write_ctx;
988 if (s->enc_write_ctx == NULL)
989 enc = NULL;
990 else {
991 int ivlen;
992
993 enc = EVP_CIPHER_CTX_get0_cipher(s->enc_write_ctx);
994 /* For TLSv1.1 and later explicit IV */
995 if (SSL_USE_EXPLICIT_IV(s)
996 && EVP_CIPHER_get_mode(enc) == EVP_CIPH_CBC_MODE)
997 ivlen = EVP_CIPHER_get_iv_length(enc);
998 else
999 ivlen = 0;
1000 if (ivlen > 1) {
1001 for (ctr = 0; ctr < n_recs; ctr++) {
1002 if (recs[ctr].data != recs[ctr].input) {
1003 /*
1004 * we can't write into the input stream: Can this ever
1005 * happen?? (steve)
1006 */
1007 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1008 return 0;
1009 } else if (RAND_bytes_ex(s->ctx->libctx, recs[ctr].input,
1010 ivlen, 0) <= 0) {
1011 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1012 return 0;
1013 }
1014 }
1015 }
1016 }
1017 } else {
1018 if (EVP_MD_CTX_get0_md(s->read_hash)) {
1019 int n = EVP_MD_CTX_get_size(s->read_hash);
1020 if (!ossl_assert(n >= 0)) {
1021 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1022 return 0;
1023 }
1024 }
1025 ds = s->enc_read_ctx;
1026 if (s->enc_read_ctx == NULL)
1027 enc = NULL;
1028 else
1029 enc = EVP_CIPHER_CTX_get0_cipher(s->enc_read_ctx);
1030 }
1031
1032 if ((s->session == NULL) || (ds == NULL) || (enc == NULL)) {
1033 for (ctr = 0; ctr < n_recs; ctr++) {
1034 memmove(recs[ctr].data, recs[ctr].input, recs[ctr].length);
1035 recs[ctr].input = recs[ctr].data;
1036 }
1037 } else {
1038 int provided = (EVP_CIPHER_get0_provider(enc) != NULL);
1039
1040 bs = EVP_CIPHER_get_block_size(EVP_CIPHER_CTX_get0_cipher(ds));
1041
1042 if (n_recs > 1) {
1043 if ((EVP_CIPHER_get_flags(EVP_CIPHER_CTX_get0_cipher(ds))
1044 & EVP_CIPH_FLAG_PIPELINE) == 0) {
1045 /*
1046 * We shouldn't have been called with pipeline data if the
1047 * cipher doesn't support pipelining
1048 */
1049 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_PIPELINE_FAILURE);
1050 return 0;
1051 }
1052 }
1053 for (ctr = 0; ctr < n_recs; ctr++) {
1054 reclen[ctr] = recs[ctr].length;
1055
1056 if ((EVP_CIPHER_get_flags(EVP_CIPHER_CTX_get0_cipher(ds))
1057 & EVP_CIPH_FLAG_AEAD_CIPHER) != 0) {
1058 unsigned char *seq;
1059
1060 seq = sending ? RECORD_LAYER_get_write_sequence(&s->rlayer)
1061 : RECORD_LAYER_get_read_sequence(&s->rlayer);
1062
1063 if (SSL_IS_DTLS(s)) {
1064 /* DTLS does not support pipelining */
1065 unsigned char dtlsseq[8], *p = dtlsseq;
1066
1067 s2n(sending ? DTLS_RECORD_LAYER_get_w_epoch(&s->rlayer) :
1068 DTLS_RECORD_LAYER_get_r_epoch(&s->rlayer), p);
1069 memcpy(p, &seq[2], 6);
1070 memcpy(buf[ctr], dtlsseq, 8);
1071 } else {
1072 memcpy(buf[ctr], seq, 8);
1073 for (i = 7; i >= 0; i--) { /* increment */
1074 ++seq[i];
1075 if (seq[i] != 0)
1076 break;
1077 }
1078 }
1079
1080 buf[ctr][8] = recs[ctr].type;
1081 buf[ctr][9] = (unsigned char)(s->version >> 8);
1082 buf[ctr][10] = (unsigned char)(s->version);
1083 buf[ctr][11] = (unsigned char)(recs[ctr].length >> 8);
1084 buf[ctr][12] = (unsigned char)(recs[ctr].length & 0xff);
1085 pad = EVP_CIPHER_CTX_ctrl(ds, EVP_CTRL_AEAD_TLS1_AAD,
1086 EVP_AEAD_TLS1_AAD_LEN, buf[ctr]);
1087 if (pad <= 0) {
1088 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1089 return 0;
1090 }
1091
1092 if (sending) {
1093 reclen[ctr] += pad;
1094 recs[ctr].length += pad;
1095 }
1096
1097 } else if ((bs != 1) && sending && !provided) {
1098 /*
1099 * We only do this for legacy ciphers. Provided ciphers add the
1100 * padding on the provider side.
1101 */
1102 padnum = bs - (reclen[ctr] % bs);
1103
1104 /* Add weird padding of up to 256 bytes */
1105
1106 if (padnum > MAX_PADDING) {
1107 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1108 return 0;
1109 }
1110 /* we need to add 'padnum' padding bytes of value padval */
1111 padval = (unsigned char)(padnum - 1);
1112 for (loop = reclen[ctr]; loop < reclen[ctr] + padnum; loop++)
1113 recs[ctr].input[loop] = padval;
1114 reclen[ctr] += padnum;
1115 recs[ctr].length += padnum;
1116 }
1117
1118 if (!sending) {
1119 if (reclen[ctr] == 0 || reclen[ctr] % bs != 0) {
1120 /* Publicly invalid */
1121 return 0;
1122 }
1123 }
1124 }
1125 if (n_recs > 1) {
1126 unsigned char *data[SSL_MAX_PIPELINES];
1127
1128 /* Set the output buffers */
1129 for (ctr = 0; ctr < n_recs; ctr++) {
1130 data[ctr] = recs[ctr].data;
1131 }
1132 if (EVP_CIPHER_CTX_ctrl(ds, EVP_CTRL_SET_PIPELINE_OUTPUT_BUFS,
1133 (int)n_recs, data) <= 0) {
1134 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_PIPELINE_FAILURE);
1135 return 0;
1136 }
1137 /* Set the input buffers */
1138 for (ctr = 0; ctr < n_recs; ctr++) {
1139 data[ctr] = recs[ctr].input;
1140 }
1141 if (EVP_CIPHER_CTX_ctrl(ds, EVP_CTRL_SET_PIPELINE_INPUT_BUFS,
1142 (int)n_recs, data) <= 0
1143 || EVP_CIPHER_CTX_ctrl(ds, EVP_CTRL_SET_PIPELINE_INPUT_LENS,
1144 (int)n_recs, reclen) <= 0) {
1145 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_PIPELINE_FAILURE);
1146 return 0;
1147 }
1148 }
1149
1150 if (!SSL_IS_DTLS(s) && tlstree_enc) {
1151 unsigned char *seq;
1152 int decrement_seq = 0;
1153
1154 /*
1155 * When sending, seq is incremented after MAC calculation.
1156 * So if we are in ETM mode, we use seq 'as is' in the ctrl-function.
1157 * Otherwise we have to decrease it in the implementation
1158 */
1159 if (sending && !SSL_WRITE_ETM(s))
1160 decrement_seq = 1;
1161
1162 seq = sending ? RECORD_LAYER_get_write_sequence(&s->rlayer)
1163 : RECORD_LAYER_get_read_sequence(&s->rlayer);
1164 if (EVP_CIPHER_CTX_ctrl(ds, EVP_CTRL_TLSTREE, decrement_seq, seq) <= 0) {
1165 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1166 return 0;
1167 }
1168 }
1169
1170 if (provided) {
1171 int outlen;
1172
1173 /* Provided cipher - we do not support pipelining on this path */
1174 if (n_recs > 1) {
1175 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1176 return 0;
1177 }
1178
1179 if (!EVP_CipherUpdate(ds, recs[0].data, &outlen, recs[0].input,
1180 (unsigned int)reclen[0]))
1181 return 0;
1182 recs[0].length = outlen;
1183
1184 /*
1185 * The length returned from EVP_CipherUpdate above is the actual
1186 * payload length. We need to adjust the data/input ptr to skip over
1187 * any explicit IV
1188 */
1189 if (!sending) {
1190 if (EVP_CIPHER_get_mode(enc) == EVP_CIPH_GCM_MODE) {
1191 recs[0].data += EVP_GCM_TLS_EXPLICIT_IV_LEN;
1192 recs[0].input += EVP_GCM_TLS_EXPLICIT_IV_LEN;
1193 } else if (EVP_CIPHER_get_mode(enc) == EVP_CIPH_CCM_MODE) {
1194 recs[0].data += EVP_CCM_TLS_EXPLICIT_IV_LEN;
1195 recs[0].input += EVP_CCM_TLS_EXPLICIT_IV_LEN;
1196 } else if (bs != 1 && SSL_USE_EXPLICIT_IV(s)) {
1197 recs[0].data += bs;
1198 recs[0].input += bs;
1199 recs[0].orig_len -= bs;
1200 }
1201
1202 /* Now get a pointer to the MAC (if applicable) */
1203 if (macs != NULL) {
1204 OSSL_PARAM params[2], *p = params;
1205
1206 /* Get the MAC */
1207 macs[0].alloced = 0;
1208
1209 *p++ = OSSL_PARAM_construct_octet_ptr(OSSL_CIPHER_PARAM_TLS_MAC,
1210 (void **)&macs[0].mac,
1211 macsize);
1212 *p = OSSL_PARAM_construct_end();
1213
1214 if (!EVP_CIPHER_CTX_get_params(ds, params)) {
1215 /* Shouldn't normally happen */
1216 SSLfatal(s, SSL_AD_INTERNAL_ERROR,
1217 ERR_R_INTERNAL_ERROR);
1218 return 0;
1219 }
1220 }
1221 }
1222 } else {
1223 /* Legacy cipher */
1224
1225 tmpr = EVP_Cipher(ds, recs[0].data, recs[0].input,
1226 (unsigned int)reclen[0]);
1227 if ((EVP_CIPHER_get_flags(EVP_CIPHER_CTX_get0_cipher(ds))
1228 & EVP_CIPH_FLAG_CUSTOM_CIPHER) != 0
1229 ? (tmpr < 0)
1230 : (tmpr == 0)) {
1231 /* AEAD can fail to verify MAC */
1232 return 0;
1233 }
1234
1235 if (!sending) {
1236 for (ctr = 0; ctr < n_recs; ctr++) {
1237 /* Adjust the record to remove the explicit IV/MAC/Tag */
1238 if (EVP_CIPHER_get_mode(enc) == EVP_CIPH_GCM_MODE) {
1239 recs[ctr].data += EVP_GCM_TLS_EXPLICIT_IV_LEN;
1240 recs[ctr].input += EVP_GCM_TLS_EXPLICIT_IV_LEN;
1241 recs[ctr].length -= EVP_GCM_TLS_EXPLICIT_IV_LEN;
1242 } else if (EVP_CIPHER_get_mode(enc) == EVP_CIPH_CCM_MODE) {
1243 recs[ctr].data += EVP_CCM_TLS_EXPLICIT_IV_LEN;
1244 recs[ctr].input += EVP_CCM_TLS_EXPLICIT_IV_LEN;
1245 recs[ctr].length -= EVP_CCM_TLS_EXPLICIT_IV_LEN;
1246 } else if (bs != 1 && SSL_USE_EXPLICIT_IV(s)) {
1247 if (recs[ctr].length < bs)
1248 return 0;
1249 recs[ctr].data += bs;
1250 recs[ctr].input += bs;
1251 recs[ctr].length -= bs;
1252 recs[ctr].orig_len -= bs;
1253 }
1254
1255 /*
1256 * If using Mac-then-encrypt, then this will succeed but
1257 * with a random MAC if padding is invalid
1258 */
1259 if (!tls1_cbc_remove_padding_and_mac(&recs[ctr].length,
1260 recs[ctr].orig_len,
1261 recs[ctr].data,
1262 (macs != NULL) ? &macs[ctr].mac : NULL,
1263 (macs != NULL) ? &macs[ctr].alloced
1264 : NULL,
1265 bs,
1266 pad ? (size_t)pad : macsize,
1267 (EVP_CIPHER_get_flags(enc)
1268 & EVP_CIPH_FLAG_AEAD_CIPHER) != 0,
1269 s->ctx->libctx))
1270 return 0;
1271 }
1272 }
1273 }
1274 }
1275 return 1;
1276 }
1277
1278 /*
1279 * ssl3_cbc_record_digest_supported returns 1 iff |ctx| uses a hash function
1280 * which ssl3_cbc_digest_record supports.
1281 */
ssl3_cbc_record_digest_supported(const EVP_MD_CTX * ctx)1282 char ssl3_cbc_record_digest_supported(const EVP_MD_CTX *ctx)
1283 {
1284 switch (EVP_MD_CTX_get_type(ctx)) {
1285 case NID_md5:
1286 case NID_sha1:
1287 case NID_sha224:
1288 case NID_sha256:
1289 case NID_sha384:
1290 case NID_sha512:
1291 return 1;
1292 default:
1293 return 0;
1294 }
1295 }
1296
n_ssl3_mac(SSL * ssl,SSL3_RECORD * rec,unsigned char * md,int sending)1297 int n_ssl3_mac(SSL *ssl, SSL3_RECORD *rec, unsigned char *md, int sending)
1298 {
1299 unsigned char *mac_sec, *seq;
1300 const EVP_MD_CTX *hash;
1301 unsigned char *p, rec_char;
1302 size_t md_size;
1303 size_t npad;
1304 int t;
1305
1306 if (sending) {
1307 mac_sec = &(ssl->s3.write_mac_secret[0]);
1308 seq = RECORD_LAYER_get_write_sequence(&ssl->rlayer);
1309 hash = ssl->write_hash;
1310 } else {
1311 mac_sec = &(ssl->s3.read_mac_secret[0]);
1312 seq = RECORD_LAYER_get_read_sequence(&ssl->rlayer);
1313 hash = ssl->read_hash;
1314 }
1315
1316 t = EVP_MD_CTX_get_size(hash);
1317 if (t < 0)
1318 return 0;
1319 md_size = t;
1320 npad = (48 / md_size) * md_size;
1321
1322 if (!sending
1323 && EVP_CIPHER_CTX_get_mode(ssl->enc_read_ctx) == EVP_CIPH_CBC_MODE
1324 && ssl3_cbc_record_digest_supported(hash)) {
1325 #ifdef OPENSSL_NO_DEPRECATED_3_0
1326 return 0;
1327 #else
1328 /*
1329 * This is a CBC-encrypted record. We must avoid leaking any
1330 * timing-side channel information about how many blocks of data we
1331 * are hashing because that gives an attacker a timing-oracle.
1332 */
1333
1334 /*-
1335 * npad is, at most, 48 bytes and that's with MD5:
1336 * 16 + 48 + 8 (sequence bytes) + 1 + 2 = 75.
1337 *
1338 * With SHA-1 (the largest hash speced for SSLv3) the hash size
1339 * goes up 4, but npad goes down by 8, resulting in a smaller
1340 * total size.
1341 */
1342 unsigned char header[75];
1343 size_t j = 0;
1344 memcpy(header + j, mac_sec, md_size);
1345 j += md_size;
1346 memcpy(header + j, ssl3_pad_1, npad);
1347 j += npad;
1348 memcpy(header + j, seq, 8);
1349 j += 8;
1350 header[j++] = rec->type;
1351 header[j++] = (unsigned char)(rec->length >> 8);
1352 header[j++] = (unsigned char)(rec->length & 0xff);
1353
1354 /* Final param == is SSLv3 */
1355 if (ssl3_cbc_digest_record(EVP_MD_CTX_get0_md(hash),
1356 md, &md_size,
1357 header, rec->input,
1358 rec->length, rec->orig_len,
1359 mac_sec, md_size, 1) <= 0)
1360 return 0;
1361 #endif
1362 } else {
1363 unsigned int md_size_u;
1364 /* Chop the digest off the end :-) */
1365 EVP_MD_CTX *md_ctx = EVP_MD_CTX_new();
1366
1367 if (md_ctx == NULL)
1368 return 0;
1369
1370 rec_char = rec->type;
1371 p = md;
1372 s2n(rec->length, p);
1373 if (EVP_MD_CTX_copy_ex(md_ctx, hash) <= 0
1374 || EVP_DigestUpdate(md_ctx, mac_sec, md_size) <= 0
1375 || EVP_DigestUpdate(md_ctx, ssl3_pad_1, npad) <= 0
1376 || EVP_DigestUpdate(md_ctx, seq, 8) <= 0
1377 || EVP_DigestUpdate(md_ctx, &rec_char, 1) <= 0
1378 || EVP_DigestUpdate(md_ctx, md, 2) <= 0
1379 || EVP_DigestUpdate(md_ctx, rec->input, rec->length) <= 0
1380 || EVP_DigestFinal_ex(md_ctx, md, NULL) <= 0
1381 || EVP_MD_CTX_copy_ex(md_ctx, hash) <= 0
1382 || EVP_DigestUpdate(md_ctx, mac_sec, md_size) <= 0
1383 || EVP_DigestUpdate(md_ctx, ssl3_pad_2, npad) <= 0
1384 || EVP_DigestUpdate(md_ctx, md, md_size) <= 0
1385 || EVP_DigestFinal_ex(md_ctx, md, &md_size_u) <= 0) {
1386 EVP_MD_CTX_free(md_ctx);
1387 return 0;
1388 }
1389
1390 EVP_MD_CTX_free(md_ctx);
1391 }
1392
1393 ssl3_record_sequence_update(seq);
1394 return 1;
1395 }
1396
tls1_mac(SSL * ssl,SSL3_RECORD * rec,unsigned char * md,int sending)1397 int tls1_mac(SSL *ssl, SSL3_RECORD *rec, unsigned char *md, int sending)
1398 {
1399 unsigned char *seq;
1400 EVP_MD_CTX *hash;
1401 size_t md_size;
1402 int i;
1403 EVP_MD_CTX *hmac = NULL, *mac_ctx;
1404 unsigned char header[13];
1405 int stream_mac = sending ? (ssl->mac_flags & SSL_MAC_FLAG_WRITE_MAC_STREAM)
1406 : (ssl->mac_flags & SSL_MAC_FLAG_READ_MAC_STREAM);
1407 int tlstree_mac = sending ? (ssl->mac_flags & SSL_MAC_FLAG_WRITE_MAC_TLSTREE)
1408 : (ssl->mac_flags & SSL_MAC_FLAG_READ_MAC_TLSTREE);
1409 int t;
1410 int ret = 0;
1411
1412 if (sending) {
1413 seq = RECORD_LAYER_get_write_sequence(&ssl->rlayer);
1414 hash = ssl->write_hash;
1415 } else {
1416 seq = RECORD_LAYER_get_read_sequence(&ssl->rlayer);
1417 hash = ssl->read_hash;
1418 }
1419
1420 t = EVP_MD_CTX_get_size(hash);
1421 if (!ossl_assert(t >= 0))
1422 return 0;
1423 md_size = t;
1424
1425 /* I should fix this up TLS TLS TLS TLS TLS XXXXXXXX */
1426 if (stream_mac) {
1427 mac_ctx = hash;
1428 } else {
1429 hmac = EVP_MD_CTX_new();
1430 if (hmac == NULL || !EVP_MD_CTX_copy(hmac, hash)) {
1431 goto end;
1432 }
1433 mac_ctx = hmac;
1434 }
1435
1436 if (!SSL_IS_DTLS(ssl) && tlstree_mac && EVP_MD_CTX_ctrl(mac_ctx, EVP_MD_CTRL_TLSTREE, 0, seq) <= 0) {
1437 goto end;
1438 }
1439
1440 if (SSL_IS_DTLS(ssl)) {
1441 unsigned char dtlsseq[8], *p = dtlsseq;
1442
1443 s2n(sending ? DTLS_RECORD_LAYER_get_w_epoch(&ssl->rlayer) :
1444 DTLS_RECORD_LAYER_get_r_epoch(&ssl->rlayer), p);
1445 memcpy(p, &seq[2], 6);
1446
1447 memcpy(header, dtlsseq, 8);
1448 } else
1449 memcpy(header, seq, 8);
1450
1451 header[8] = rec->type;
1452 header[9] = (unsigned char)(ssl->version >> 8);
1453 header[10] = (unsigned char)(ssl->version);
1454 header[11] = (unsigned char)(rec->length >> 8);
1455 header[12] = (unsigned char)(rec->length & 0xff);
1456
1457 if (!sending && !SSL_READ_ETM(ssl)
1458 && EVP_CIPHER_CTX_get_mode(ssl->enc_read_ctx) == EVP_CIPH_CBC_MODE
1459 && ssl3_cbc_record_digest_supported(mac_ctx)) {
1460 OSSL_PARAM tls_hmac_params[2], *p = tls_hmac_params;
1461
1462 *p++ = OSSL_PARAM_construct_size_t(OSSL_MAC_PARAM_TLS_DATA_SIZE,
1463 &rec->orig_len);
1464 *p++ = OSSL_PARAM_construct_end();
1465
1466 if (!EVP_PKEY_CTX_set_params(EVP_MD_CTX_get_pkey_ctx(mac_ctx),
1467 tls_hmac_params)) {
1468 goto end;
1469 }
1470 }
1471
1472 if (EVP_DigestSignUpdate(mac_ctx, header, sizeof(header)) <= 0
1473 || EVP_DigestSignUpdate(mac_ctx, rec->input, rec->length) <= 0
1474 || EVP_DigestSignFinal(mac_ctx, md, &md_size) <= 0) {
1475 goto end;
1476 }
1477
1478 OSSL_TRACE_BEGIN(TLS) {
1479 BIO_printf(trc_out, "seq:\n");
1480 BIO_dump_indent(trc_out, seq, 8, 4);
1481 BIO_printf(trc_out, "rec:\n");
1482 BIO_dump_indent(trc_out, rec->data, rec->length, 4);
1483 } OSSL_TRACE_END(TLS);
1484
1485 if (!SSL_IS_DTLS(ssl)) {
1486 for (i = 7; i >= 0; i--) {
1487 ++seq[i];
1488 if (seq[i] != 0)
1489 break;
1490 }
1491 }
1492 OSSL_TRACE_BEGIN(TLS) {
1493 BIO_printf(trc_out, "md:\n");
1494 BIO_dump_indent(trc_out, md, md_size, 4);
1495 } OSSL_TRACE_END(TLS);
1496 ret = 1;
1497 end:
1498 EVP_MD_CTX_free(hmac);
1499 return ret;
1500 }
1501
dtls1_process_record(SSL * s,DTLS1_BITMAP * bitmap)1502 int dtls1_process_record(SSL *s, DTLS1_BITMAP *bitmap)
1503 {
1504 int i;
1505 int enc_err;
1506 SSL_SESSION *sess;
1507 SSL3_RECORD *rr;
1508 int imac_size;
1509 size_t mac_size = 0;
1510 unsigned char md[EVP_MAX_MD_SIZE];
1511 size_t max_plain_length = SSL3_RT_MAX_PLAIN_LENGTH;
1512 SSL_MAC_BUF macbuf = { NULL, 0 };
1513 int ret = 0;
1514
1515 rr = RECORD_LAYER_get_rrec(&s->rlayer);
1516 sess = s->session;
1517
1518 /*
1519 * At this point, s->rlayer.packet_length == SSL3_RT_HEADER_LNGTH + rr->length,
1520 * and we have that many bytes in s->rlayer.packet
1521 */
1522 rr->input = &(RECORD_LAYER_get_packet(&s->rlayer)[DTLS1_RT_HEADER_LENGTH]);
1523
1524 /*
1525 * ok, we can now read from 's->rlayer.packet' data into 'rr'. rr->input
1526 * points at rr->length bytes, which need to be copied into rr->data by
1527 * either the decryption or by the decompression. When the data is 'copied'
1528 * into the rr->data buffer, rr->input will be pointed at the new buffer
1529 */
1530
1531 /*
1532 * We now have - encrypted [ MAC [ compressed [ plain ] ] ] rr->length
1533 * bytes of encrypted compressed stuff.
1534 */
1535
1536 /* check is not needed I believe */
1537 if (rr->length > SSL3_RT_MAX_ENCRYPTED_LENGTH) {
1538 SSLfatal(s, SSL_AD_RECORD_OVERFLOW, SSL_R_ENCRYPTED_LENGTH_TOO_LONG);
1539 return 0;
1540 }
1541
1542 /* decrypt in place in 'rr->input' */
1543 rr->data = rr->input;
1544 rr->orig_len = rr->length;
1545
1546 if (s->read_hash != NULL) {
1547 const EVP_MD *tmpmd = EVP_MD_CTX_get0_md(s->read_hash);
1548
1549 if (tmpmd != NULL) {
1550 imac_size = EVP_MD_get_size(tmpmd);
1551 if (!ossl_assert(imac_size >= 0 && imac_size <= EVP_MAX_MD_SIZE)) {
1552 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_EVP_LIB);
1553 return 0;
1554 }
1555 mac_size = (size_t)imac_size;
1556 }
1557 }
1558
1559 if (SSL_READ_ETM(s) && s->read_hash) {
1560 unsigned char *mac;
1561
1562 if (rr->orig_len < mac_size) {
1563 SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_TOO_SHORT);
1564 return 0;
1565 }
1566 rr->length -= mac_size;
1567 mac = rr->data + rr->length;
1568 i = s->method->ssl3_enc->mac(s, rr, md, 0 /* not send */ );
1569 if (i == 0 || CRYPTO_memcmp(md, mac, (size_t)mac_size) != 0) {
1570 SSLfatal(s, SSL_AD_BAD_RECORD_MAC,
1571 SSL_R_DECRYPTION_FAILED_OR_BAD_RECORD_MAC);
1572 return 0;
1573 }
1574 /*
1575 * We've handled the mac now - there is no MAC inside the encrypted
1576 * record
1577 */
1578 mac_size = 0;
1579 }
1580
1581 /*
1582 * Set a mark around the packet decryption attempt. This is DTLS, so
1583 * bad packets are just ignored, and we don't want to leave stray
1584 * errors in the queue from processing bogus junk that we ignored.
1585 */
1586 ERR_set_mark();
1587 enc_err = s->method->ssl3_enc->enc(s, rr, 1, 0, &macbuf, mac_size);
1588
1589 /*-
1590 * enc_err is:
1591 * 0: if the record is publicly invalid, or an internal error, or AEAD
1592 * decryption failed, or ETM decryption failed.
1593 * 1: Success or MTE decryption failed (MAC will be randomised)
1594 */
1595 if (enc_err == 0) {
1596 ERR_pop_to_mark();
1597 if (ossl_statem_in_error(s)) {
1598 /* SSLfatal() got called */
1599 goto end;
1600 }
1601 /* For DTLS we simply ignore bad packets. */
1602 rr->length = 0;
1603 RECORD_LAYER_reset_packet_length(&s->rlayer);
1604 goto end;
1605 }
1606 ERR_clear_last_mark();
1607 OSSL_TRACE_BEGIN(TLS) {
1608 BIO_printf(trc_out, "dec %zd\n", rr->length);
1609 BIO_dump_indent(trc_out, rr->data, rr->length, 4);
1610 } OSSL_TRACE_END(TLS);
1611
1612 /* r->length is now the compressed data plus mac */
1613 if ((sess != NULL)
1614 && !SSL_READ_ETM(s)
1615 && (s->enc_read_ctx != NULL)
1616 && (EVP_MD_CTX_get0_md(s->read_hash) != NULL)) {
1617 /* s->read_hash != NULL => mac_size != -1 */
1618
1619 i = s->method->ssl3_enc->mac(s, rr, md, 0 /* not send */ );
1620 if (i == 0 || macbuf.mac == NULL
1621 || CRYPTO_memcmp(md, macbuf.mac, mac_size) != 0)
1622 enc_err = 0;
1623 if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH + mac_size)
1624 enc_err = 0;
1625 }
1626
1627 if (enc_err == 0) {
1628 /* decryption failed, silently discard message */
1629 rr->length = 0;
1630 RECORD_LAYER_reset_packet_length(&s->rlayer);
1631 goto end;
1632 }
1633
1634 /* r->length is now just compressed */
1635 if (s->expand != NULL) {
1636 if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH) {
1637 SSLfatal(s, SSL_AD_RECORD_OVERFLOW,
1638 SSL_R_COMPRESSED_LENGTH_TOO_LONG);
1639 goto end;
1640 }
1641 if (!ssl3_do_uncompress(s, rr)) {
1642 SSLfatal(s, SSL_AD_DECOMPRESSION_FAILURE, SSL_R_BAD_DECOMPRESSION);
1643 goto end;
1644 }
1645 }
1646
1647 /* use current Max Fragment Length setting if applicable */
1648 if (s->session != NULL && USE_MAX_FRAGMENT_LENGTH_EXT(s->session))
1649 max_plain_length = GET_MAX_FRAGMENT_LENGTH(s->session);
1650
1651 /* send overflow if the plaintext is too long now it has passed MAC */
1652 if (rr->length > max_plain_length) {
1653 SSLfatal(s, SSL_AD_RECORD_OVERFLOW, SSL_R_DATA_LENGTH_TOO_LONG);
1654 goto end;
1655 }
1656
1657 rr->off = 0;
1658 /*-
1659 * So at this point the following is true
1660 * ssl->s3.rrec.type is the type of record
1661 * ssl->s3.rrec.length == number of bytes in record
1662 * ssl->s3.rrec.off == offset to first valid byte
1663 * ssl->s3.rrec.data == where to take bytes from, increment
1664 * after use :-).
1665 */
1666
1667 /* we have pulled in a full packet so zero things */
1668 RECORD_LAYER_reset_packet_length(&s->rlayer);
1669
1670 /* Mark receipt of record. */
1671 dtls1_record_bitmap_update(s, bitmap);
1672
1673 ret = 1;
1674 end:
1675 if (macbuf.alloced)
1676 OPENSSL_free(macbuf.mac);
1677 return ret;
1678 }
1679
1680 /*
1681 * Retrieve a buffered record that belongs to the current epoch, i.e. processed
1682 */
1683 #define dtls1_get_processed_record(s) \
1684 dtls1_retrieve_buffered_record((s), \
1685 &(DTLS_RECORD_LAYER_get_processed_rcds(&s->rlayer)))
1686
1687 /*-
1688 * Call this to get a new input record.
1689 * It will return <= 0 if more data is needed, normally due to an error
1690 * or non-blocking IO.
1691 * When it finishes, one packet has been decoded and can be found in
1692 * ssl->s3.rrec.type - is the type of record
1693 * ssl->s3.rrec.data - data
1694 * ssl->s3.rrec.length - number of bytes
1695 */
1696 /* used only by dtls1_read_bytes */
dtls1_get_record(SSL * s)1697 int dtls1_get_record(SSL *s)
1698 {
1699 int ssl_major, ssl_minor;
1700 int rret;
1701 size_t more, n;
1702 SSL3_RECORD *rr;
1703 unsigned char *p = NULL;
1704 unsigned short version;
1705 DTLS1_BITMAP *bitmap;
1706 unsigned int is_next_epoch;
1707
1708 rr = RECORD_LAYER_get_rrec(&s->rlayer);
1709
1710 again:
1711 /*
1712 * The epoch may have changed. If so, process all the pending records.
1713 * This is a non-blocking operation.
1714 */
1715 if (!dtls1_process_buffered_records(s)) {
1716 /* SSLfatal() already called */
1717 return -1;
1718 }
1719
1720 /* if we're renegotiating, then there may be buffered records */
1721 if (dtls1_get_processed_record(s))
1722 return 1;
1723
1724 /* get something from the wire */
1725
1726 /* check if we have the header */
1727 if ((RECORD_LAYER_get_rstate(&s->rlayer) != SSL_ST_READ_BODY) ||
1728 (RECORD_LAYER_get_packet_length(&s->rlayer) < DTLS1_RT_HEADER_LENGTH)) {
1729 rret = ssl3_read_n(s, DTLS1_RT_HEADER_LENGTH,
1730 SSL3_BUFFER_get_len(&s->rlayer.rbuf), 0, 1, &n);
1731 /* read timeout is handled by dtls1_read_bytes */
1732 if (rret <= 0) {
1733 /* SSLfatal() already called if appropriate */
1734 return rret; /* error or non-blocking */
1735 }
1736
1737 /* this packet contained a partial record, dump it */
1738 if (RECORD_LAYER_get_packet_length(&s->rlayer) !=
1739 DTLS1_RT_HEADER_LENGTH) {
1740 RECORD_LAYER_reset_packet_length(&s->rlayer);
1741 goto again;
1742 }
1743
1744 RECORD_LAYER_set_rstate(&s->rlayer, SSL_ST_READ_BODY);
1745
1746 p = RECORD_LAYER_get_packet(&s->rlayer);
1747
1748 if (s->msg_callback)
1749 s->msg_callback(0, 0, SSL3_RT_HEADER, p, DTLS1_RT_HEADER_LENGTH,
1750 s, s->msg_callback_arg);
1751
1752 /* Pull apart the header into the DTLS1_RECORD */
1753 rr->type = *(p++);
1754 ssl_major = *(p++);
1755 ssl_minor = *(p++);
1756 version = (ssl_major << 8) | ssl_minor;
1757
1758 /* sequence number is 64 bits, with top 2 bytes = epoch */
1759 n2s(p, rr->epoch);
1760
1761 memcpy(&(RECORD_LAYER_get_read_sequence(&s->rlayer)[2]), p, 6);
1762 p += 6;
1763
1764 n2s(p, rr->length);
1765 rr->read = 0;
1766
1767 /*
1768 * Lets check the version. We tolerate alerts that don't have the exact
1769 * version number (e.g. because of protocol version errors)
1770 */
1771 if (!s->first_packet && rr->type != SSL3_RT_ALERT) {
1772 if (version != s->version) {
1773 /* unexpected version, silently discard */
1774 rr->length = 0;
1775 rr->read = 1;
1776 RECORD_LAYER_reset_packet_length(&s->rlayer);
1777 goto again;
1778 }
1779 }
1780
1781 if ((version & 0xff00) != (s->version & 0xff00)) {
1782 /* wrong version, silently discard record */
1783 rr->length = 0;
1784 rr->read = 1;
1785 RECORD_LAYER_reset_packet_length(&s->rlayer);
1786 goto again;
1787 }
1788
1789 if (rr->length > SSL3_RT_MAX_ENCRYPTED_LENGTH) {
1790 /* record too long, silently discard it */
1791 rr->length = 0;
1792 rr->read = 1;
1793 RECORD_LAYER_reset_packet_length(&s->rlayer);
1794 goto again;
1795 }
1796
1797 /* If received packet overflows own-client Max Fragment Length setting */
1798 if (s->session != NULL && USE_MAX_FRAGMENT_LENGTH_EXT(s->session)
1799 && rr->length > GET_MAX_FRAGMENT_LENGTH(s->session) + SSL3_RT_MAX_ENCRYPTED_OVERHEAD) {
1800 /* record too long, silently discard it */
1801 rr->length = 0;
1802 rr->read = 1;
1803 RECORD_LAYER_reset_packet_length(&s->rlayer);
1804 goto again;
1805 }
1806
1807 /* now s->rlayer.rstate == SSL_ST_READ_BODY */
1808 }
1809
1810 /* s->rlayer.rstate == SSL_ST_READ_BODY, get and decode the data */
1811
1812 if (rr->length >
1813 RECORD_LAYER_get_packet_length(&s->rlayer) - DTLS1_RT_HEADER_LENGTH) {
1814 /* now s->rlayer.packet_length == DTLS1_RT_HEADER_LENGTH */
1815 more = rr->length;
1816 rret = ssl3_read_n(s, more, more, 1, 1, &n);
1817 /* this packet contained a partial record, dump it */
1818 if (rret <= 0 || n != more) {
1819 if (ossl_statem_in_error(s)) {
1820 /* ssl3_read_n() called SSLfatal() */
1821 return -1;
1822 }
1823 rr->length = 0;
1824 rr->read = 1;
1825 RECORD_LAYER_reset_packet_length(&s->rlayer);
1826 goto again;
1827 }
1828
1829 /*
1830 * now n == rr->length, and s->rlayer.packet_length ==
1831 * DTLS1_RT_HEADER_LENGTH + rr->length
1832 */
1833 }
1834 /* set state for later operations */
1835 RECORD_LAYER_set_rstate(&s->rlayer, SSL_ST_READ_HEADER);
1836
1837 /* match epochs. NULL means the packet is dropped on the floor */
1838 bitmap = dtls1_get_bitmap(s, rr, &is_next_epoch);
1839 if (bitmap == NULL) {
1840 rr->length = 0;
1841 RECORD_LAYER_reset_packet_length(&s->rlayer); /* dump this record */
1842 goto again; /* get another record */
1843 }
1844 #ifndef OPENSSL_NO_SCTP
1845 /* Only do replay check if no SCTP bio */
1846 if (!BIO_dgram_is_sctp(SSL_get_rbio(s))) {
1847 #endif
1848 /* Check whether this is a repeat, or aged record. */
1849 if (!dtls1_record_replay_check(s, bitmap)) {
1850 rr->length = 0;
1851 rr->read = 1;
1852 RECORD_LAYER_reset_packet_length(&s->rlayer); /* dump this record */
1853 goto again; /* get another record */
1854 }
1855 #ifndef OPENSSL_NO_SCTP
1856 }
1857 #endif
1858
1859 /* just read a 0 length packet */
1860 if (rr->length == 0) {
1861 rr->read = 1;
1862 goto again;
1863 }
1864
1865 /*
1866 * If this record is from the next epoch (either HM or ALERT), and a
1867 * handshake is currently in progress, buffer it since it cannot be
1868 * processed at this time.
1869 */
1870 if (is_next_epoch) {
1871 if ((SSL_in_init(s) || ossl_statem_get_in_handshake(s))) {
1872 if (dtls1_buffer_record (s,
1873 &(DTLS_RECORD_LAYER_get_unprocessed_rcds(&s->rlayer)),
1874 rr->seq_num) < 0) {
1875 /* SSLfatal() already called */
1876 return -1;
1877 }
1878 }
1879 rr->length = 0;
1880 rr->read = 1;
1881 RECORD_LAYER_reset_packet_length(&s->rlayer);
1882 goto again;
1883 }
1884
1885 if (!dtls1_process_record(s, bitmap)) {
1886 if (ossl_statem_in_error(s)) {
1887 /* dtls1_process_record() called SSLfatal */
1888 return -1;
1889 }
1890 rr->length = 0;
1891 rr->read = 1;
1892 RECORD_LAYER_reset_packet_length(&s->rlayer); /* dump this record */
1893 goto again; /* get another record */
1894 }
1895
1896 return 1;
1897
1898 }
1899
dtls_buffer_listen_record(SSL * s,size_t len,unsigned char * seq,size_t off)1900 int dtls_buffer_listen_record(SSL *s, size_t len, unsigned char *seq, size_t off)
1901 {
1902 SSL3_RECORD *rr;
1903
1904 rr = RECORD_LAYER_get_rrec(&s->rlayer);
1905 memset(rr, 0, sizeof(SSL3_RECORD));
1906
1907 rr->length = len;
1908 rr->type = SSL3_RT_HANDSHAKE;
1909 memcpy(rr->seq_num, seq, sizeof(rr->seq_num));
1910 rr->off = off;
1911
1912 s->rlayer.packet = RECORD_LAYER_get_rbuf(&s->rlayer)->buf;
1913 s->rlayer.packet_length = DTLS1_RT_HEADER_LENGTH + len;
1914 rr->data = s->rlayer.packet + DTLS1_RT_HEADER_LENGTH;
1915
1916 if (dtls1_buffer_record(s, &(s->rlayer.d->processed_rcds),
1917 SSL3_RECORD_get_seq_num(s->rlayer.rrec)) <= 0) {
1918 /* SSLfatal() already called */
1919 return 0;
1920 }
1921
1922 return 1;
1923 }
1924