1 /*
2 * Copyright 1995-2023 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 ERR_set_mark();
580 enc_err = s->method->ssl3_enc->enc(s, rr, num_recs, 0, macbufs, mac_size);
581
582 /*-
583 * enc_err is:
584 * 0: if the record is publicly invalid, or an internal error, or AEAD
585 * decryption failed, or ETM decryption failed.
586 * 1: Success or MTE decryption failed (MAC will be randomised)
587 */
588 if (enc_err == 0) {
589 if (ossl_statem_in_error(s)) {
590 /* SSLfatal() already got called */
591 ERR_clear_last_mark();
592 goto end;
593 }
594 if (num_recs == 1 && ossl_statem_skip_early_data(s)) {
595 /*
596 * Valid early_data that we cannot decrypt will fail here. We treat
597 * it like an empty record.
598 */
599
600 /*
601 * Remove any errors from the stack. Decryption failures are normal
602 * behaviour.
603 */
604 ERR_pop_to_mark();
605
606 thisrr = &rr[0];
607
608 if (!early_data_count_ok(s, thisrr->length,
609 EARLY_DATA_CIPHERTEXT_OVERHEAD, 0)) {
610 /* SSLfatal() already called */
611 goto end;
612 }
613
614 thisrr->length = 0;
615 thisrr->read = 1;
616 RECORD_LAYER_set_numrpipes(&s->rlayer, 1);
617 RECORD_LAYER_reset_read_sequence(&s->rlayer);
618 ret = 1;
619 goto end;
620 }
621 ERR_clear_last_mark();
622 SSLfatal(s, SSL_AD_BAD_RECORD_MAC,
623 SSL_R_DECRYPTION_FAILED_OR_BAD_RECORD_MAC);
624 goto end;
625 } else {
626 ERR_clear_last_mark();
627 }
628 OSSL_TRACE_BEGIN(TLS) {
629 BIO_printf(trc_out, "dec %lu\n", (unsigned long)rr[0].length);
630 BIO_dump_indent(trc_out, rr[0].data, rr[0].length, 4);
631 } OSSL_TRACE_END(TLS);
632
633 /* r->length is now the compressed data plus mac */
634 if ((sess != NULL)
635 && (s->enc_read_ctx != NULL)
636 && (!SSL_READ_ETM(s) && EVP_MD_CTX_get0_md(s->read_hash) != NULL)) {
637 /* s->read_hash != NULL => mac_size != -1 */
638
639 for (j = 0; j < num_recs; j++) {
640 SSL_MAC_BUF *thismb = &macbufs[j];
641 thisrr = &rr[j];
642
643 i = s->method->ssl3_enc->mac(s, thisrr, md, 0 /* not send */ );
644 if (i == 0 || thismb == NULL || thismb->mac == NULL
645 || CRYPTO_memcmp(md, thismb->mac, (size_t)mac_size) != 0)
646 enc_err = 0;
647 if (thisrr->length > SSL3_RT_MAX_COMPRESSED_LENGTH + mac_size)
648 enc_err = 0;
649 }
650 }
651
652 if (enc_err == 0) {
653 if (ossl_statem_in_error(s)) {
654 /* We already called SSLfatal() */
655 goto end;
656 }
657 /*
658 * A separate 'decryption_failed' alert was introduced with TLS 1.0,
659 * SSL 3.0 only has 'bad_record_mac'. But unless a decryption
660 * failure is directly visible from the ciphertext anyway, we should
661 * not reveal which kind of error occurred -- this might become
662 * visible to an attacker (e.g. via a logfile)
663 */
664 SSLfatal(s, SSL_AD_BAD_RECORD_MAC,
665 SSL_R_DECRYPTION_FAILED_OR_BAD_RECORD_MAC);
666 goto end;
667 }
668
669 skip_decryption:
670
671 for (j = 0; j < num_recs; j++) {
672 thisrr = &rr[j];
673
674 /* thisrr->length is now just compressed */
675 if (s->expand != NULL) {
676 if (thisrr->length > SSL3_RT_MAX_COMPRESSED_LENGTH) {
677 SSLfatal(s, SSL_AD_RECORD_OVERFLOW,
678 SSL_R_COMPRESSED_LENGTH_TOO_LONG);
679 goto end;
680 }
681 if (!ssl3_do_uncompress(s, thisrr)) {
682 SSLfatal(s, SSL_AD_DECOMPRESSION_FAILURE,
683 SSL_R_BAD_DECOMPRESSION);
684 goto end;
685 }
686 }
687
688 if (SSL_IS_TLS13(s)
689 && s->enc_read_ctx != NULL
690 && thisrr->type != SSL3_RT_ALERT) {
691 size_t end;
692
693 if (thisrr->length == 0
694 || thisrr->type != SSL3_RT_APPLICATION_DATA) {
695 SSLfatal(s, SSL_AD_UNEXPECTED_MESSAGE, SSL_R_BAD_RECORD_TYPE);
696 goto end;
697 }
698
699 /* Strip trailing padding */
700 for (end = thisrr->length - 1; end > 0 && thisrr->data[end] == 0;
701 end--)
702 continue;
703
704 thisrr->length = end;
705 thisrr->type = thisrr->data[end];
706 if (thisrr->type != SSL3_RT_APPLICATION_DATA
707 && thisrr->type != SSL3_RT_ALERT
708 && thisrr->type != SSL3_RT_HANDSHAKE) {
709 SSLfatal(s, SSL_AD_UNEXPECTED_MESSAGE, SSL_R_BAD_RECORD_TYPE);
710 goto end;
711 }
712 if (s->msg_callback)
713 s->msg_callback(0, s->version, SSL3_RT_INNER_CONTENT_TYPE,
714 &thisrr->data[end], 1, s, s->msg_callback_arg);
715 }
716
717 /*
718 * TLSv1.3 alert and handshake records are required to be non-zero in
719 * length.
720 */
721 if (SSL_IS_TLS13(s)
722 && (thisrr->type == SSL3_RT_HANDSHAKE
723 || thisrr->type == SSL3_RT_ALERT)
724 && thisrr->length == 0) {
725 SSLfatal(s, SSL_AD_UNEXPECTED_MESSAGE, SSL_R_BAD_LENGTH);
726 goto end;
727 }
728
729 /*
730 * Usually thisrr->length is the length of a single record, but when
731 * KTLS handles the decryption, thisrr->length may be larger than
732 * SSL3_RT_MAX_PLAIN_LENGTH because the kernel may have coalesced
733 * multiple records.
734 * Therefore we have to rely on KTLS to check the plaintext length
735 * limit in the kernel.
736 */
737 if (thisrr->length > SSL3_RT_MAX_PLAIN_LENGTH
738 && (!BIO_get_ktls_recv(s->rbio) || is_ktls_left)) {
739 SSLfatal(s, SSL_AD_RECORD_OVERFLOW, SSL_R_DATA_LENGTH_TOO_LONG);
740 goto end;
741 }
742
743 /*
744 * Check if the received packet overflows the current
745 * Max Fragment Length setting.
746 * Note: USE_MAX_FRAGMENT_LENGTH_EXT and KTLS are mutually exclusive.
747 */
748 if (s->session != NULL && USE_MAX_FRAGMENT_LENGTH_EXT(s->session)
749 && thisrr->length > GET_MAX_FRAGMENT_LENGTH(s->session)) {
750 SSLfatal(s, SSL_AD_RECORD_OVERFLOW, SSL_R_DATA_LENGTH_TOO_LONG);
751 goto end;
752 }
753
754 thisrr->off = 0;
755 /*-
756 * So at this point the following is true
757 * thisrr->type is the type of record
758 * thisrr->length == number of bytes in record
759 * thisrr->off == offset to first valid byte
760 * thisrr->data == where to take bytes from, increment after use :-).
761 */
762
763 /* just read a 0 length packet */
764 if (thisrr->length == 0) {
765 RECORD_LAYER_inc_empty_record_count(&s->rlayer);
766 if (RECORD_LAYER_get_empty_record_count(&s->rlayer)
767 > MAX_EMPTY_RECORDS) {
768 SSLfatal(s, SSL_AD_UNEXPECTED_MESSAGE, SSL_R_RECORD_TOO_SMALL);
769 goto end;
770 }
771 } else {
772 RECORD_LAYER_reset_empty_record_count(&s->rlayer);
773 }
774 }
775
776 if (s->early_data_state == SSL_EARLY_DATA_READING) {
777 thisrr = &rr[0];
778 if (thisrr->type == SSL3_RT_APPLICATION_DATA
779 && !early_data_count_ok(s, thisrr->length, 0, 0)) {
780 /* SSLfatal already called */
781 goto end;
782 }
783 }
784
785 RECORD_LAYER_set_numrpipes(&s->rlayer, num_recs);
786 ret = 1;
787 end:
788 if (macbufs != NULL) {
789 for (j = 0; j < num_recs; j++) {
790 if (macbufs[j].alloced)
791 OPENSSL_free(macbufs[j].mac);
792 }
793 OPENSSL_free(macbufs);
794 }
795 return ret;
796 }
797
ssl3_do_uncompress(SSL * ssl,SSL3_RECORD * rr)798 int ssl3_do_uncompress(SSL *ssl, SSL3_RECORD *rr)
799 {
800 #ifndef OPENSSL_NO_COMP
801 int i;
802
803 if (rr->comp == NULL) {
804 rr->comp = (unsigned char *)
805 OPENSSL_malloc(SSL3_RT_MAX_ENCRYPTED_LENGTH);
806 }
807 if (rr->comp == NULL)
808 return 0;
809
810 i = COMP_expand_block(ssl->expand, rr->comp,
811 SSL3_RT_MAX_PLAIN_LENGTH, rr->data, (int)rr->length);
812 if (i < 0)
813 return 0;
814 else
815 rr->length = i;
816 rr->data = rr->comp;
817 #endif
818 return 1;
819 }
820
ssl3_do_compress(SSL * ssl,SSL3_RECORD * wr)821 int ssl3_do_compress(SSL *ssl, SSL3_RECORD *wr)
822 {
823 #ifndef OPENSSL_NO_COMP
824 int i;
825
826 i = COMP_compress_block(ssl->compress, wr->data,
827 (int)(wr->length + SSL3_RT_MAX_COMPRESSED_OVERHEAD),
828 wr->input, (int)wr->length);
829 if (i < 0)
830 return 0;
831 else
832 wr->length = i;
833
834 wr->input = wr->data;
835 #endif
836 return 1;
837 }
838
839 /*-
840 * ssl3_enc encrypts/decrypts |n_recs| records in |inrecs|. Calls SSLfatal on
841 * internal error, but not otherwise. It is the responsibility of the caller to
842 * report a bad_record_mac
843 *
844 * Returns:
845 * 0: if the record is publicly invalid, or an internal error
846 * 1: Success or Mac-then-encrypt decryption failed (MAC will be randomised)
847 */
ssl3_enc(SSL * s,SSL3_RECORD * inrecs,size_t n_recs,int sending,SSL_MAC_BUF * mac,size_t macsize)848 int ssl3_enc(SSL *s, SSL3_RECORD *inrecs, size_t n_recs, int sending,
849 SSL_MAC_BUF *mac, size_t macsize)
850 {
851 SSL3_RECORD *rec;
852 EVP_CIPHER_CTX *ds;
853 size_t l, i;
854 size_t bs;
855 const EVP_CIPHER *enc;
856
857 rec = inrecs;
858 /*
859 * We shouldn't ever be called with more than one record in the SSLv3 case
860 */
861 if (n_recs != 1)
862 return 0;
863 if (sending) {
864 ds = s->enc_write_ctx;
865 if (s->enc_write_ctx == NULL)
866 enc = NULL;
867 else
868 enc = EVP_CIPHER_CTX_get0_cipher(s->enc_write_ctx);
869 } else {
870 ds = s->enc_read_ctx;
871 if (s->enc_read_ctx == NULL)
872 enc = NULL;
873 else
874 enc = EVP_CIPHER_CTX_get0_cipher(s->enc_read_ctx);
875 }
876
877 if ((s->session == NULL) || (ds == NULL) || (enc == NULL)) {
878 memmove(rec->data, rec->input, rec->length);
879 rec->input = rec->data;
880 } else {
881 int provided = (EVP_CIPHER_get0_provider(enc) != NULL);
882
883 l = rec->length;
884 bs = EVP_CIPHER_CTX_get_block_size(ds);
885
886 /* COMPRESS */
887
888 if ((bs != 1) && sending && !provided) {
889 /*
890 * We only do this for legacy ciphers. Provided ciphers add the
891 * padding on the provider side.
892 */
893 i = bs - (l % bs);
894
895 /* we need to add 'i-1' padding bytes */
896 l += i;
897 /*
898 * the last of these zero bytes will be overwritten with the
899 * padding length.
900 */
901 memset(&rec->input[rec->length], 0, i);
902 rec->length += i;
903 rec->input[l - 1] = (unsigned char)(i - 1);
904 }
905
906 if (!sending) {
907 if (l == 0 || l % bs != 0) {
908 /* Publicly invalid */
909 return 0;
910 }
911 /* otherwise, rec->length >= bs */
912 }
913
914 if (EVP_CIPHER_get0_provider(enc) != NULL) {
915 int outlen;
916
917 if (!EVP_CipherUpdate(ds, rec->data, &outlen, rec->input,
918 (unsigned int)l))
919 return 0;
920 rec->length = outlen;
921
922 if (!sending && mac != NULL) {
923 /* Now get a pointer to the MAC */
924 OSSL_PARAM params[2], *p = params;
925
926 /* Get the MAC */
927 mac->alloced = 0;
928
929 *p++ = OSSL_PARAM_construct_octet_ptr(OSSL_CIPHER_PARAM_TLS_MAC,
930 (void **)&mac->mac,
931 macsize);
932 *p = OSSL_PARAM_construct_end();
933
934 if (!EVP_CIPHER_CTX_get_params(ds, params)) {
935 /* Shouldn't normally happen */
936 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
937 return 0;
938 }
939 }
940 } else {
941 if (EVP_Cipher(ds, rec->data, rec->input, (unsigned int)l) < 1) {
942 /* Shouldn't happen */
943 SSLfatal(s, SSL_AD_BAD_RECORD_MAC, ERR_R_INTERNAL_ERROR);
944 return 0;
945 }
946
947 if (!sending)
948 return ssl3_cbc_remove_padding_and_mac(&rec->length,
949 rec->orig_len,
950 rec->data,
951 (mac != NULL) ? &mac->mac : NULL,
952 (mac != NULL) ? &mac->alloced : NULL,
953 bs,
954 macsize,
955 s->ctx->libctx);
956 }
957 }
958 return 1;
959 }
960
961 #define MAX_PADDING 256
962 /*-
963 * tls1_enc encrypts/decrypts |n_recs| in |recs|. Calls SSLfatal on internal
964 * error, but not otherwise. It is the responsibility of the caller to report
965 * a bad_record_mac - if appropriate (DTLS just drops the record).
966 *
967 * Returns:
968 * 0: if the record is publicly invalid, or an internal error, or AEAD
969 * decryption failed, or Encrypt-then-mac decryption failed.
970 * 1: Success or Mac-then-encrypt decryption failed (MAC will be randomised)
971 */
tls1_enc(SSL * s,SSL3_RECORD * recs,size_t n_recs,int sending,SSL_MAC_BUF * macs,size_t macsize)972 int tls1_enc(SSL *s, SSL3_RECORD *recs, size_t n_recs, int sending,
973 SSL_MAC_BUF *macs, size_t macsize)
974 {
975 EVP_CIPHER_CTX *ds;
976 size_t reclen[SSL_MAX_PIPELINES];
977 unsigned char buf[SSL_MAX_PIPELINES][EVP_AEAD_TLS1_AAD_LEN];
978 unsigned char *data[SSL_MAX_PIPELINES];
979 int i, pad = 0, tmpr;
980 size_t bs, ctr, padnum, loop;
981 unsigned char padval;
982 const EVP_CIPHER *enc;
983 int tlstree_enc = sending ? (s->mac_flags & SSL_MAC_FLAG_WRITE_MAC_TLSTREE)
984 : (s->mac_flags & SSL_MAC_FLAG_READ_MAC_TLSTREE);
985
986 if (n_recs == 0) {
987 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
988 return 0;
989 }
990
991 if (sending) {
992 if (EVP_MD_CTX_get0_md(s->write_hash)) {
993 int n = EVP_MD_CTX_get_size(s->write_hash);
994 if (!ossl_assert(n >= 0)) {
995 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
996 return 0;
997 }
998 }
999 ds = s->enc_write_ctx;
1000 if (s->enc_write_ctx == NULL)
1001 enc = NULL;
1002 else {
1003 int ivlen;
1004
1005 enc = EVP_CIPHER_CTX_get0_cipher(s->enc_write_ctx);
1006 /* For TLSv1.1 and later explicit IV */
1007 if (SSL_USE_EXPLICIT_IV(s)
1008 && EVP_CIPHER_get_mode(enc) == EVP_CIPH_CBC_MODE)
1009 ivlen = EVP_CIPHER_get_iv_length(enc);
1010 else
1011 ivlen = 0;
1012 if (ivlen > 1) {
1013 for (ctr = 0; ctr < n_recs; ctr++) {
1014 if (recs[ctr].data != recs[ctr].input) {
1015 /*
1016 * we can't write into the input stream: Can this ever
1017 * happen?? (steve)
1018 */
1019 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1020 return 0;
1021 } else if (RAND_bytes_ex(s->ctx->libctx, recs[ctr].input,
1022 ivlen, 0) <= 0) {
1023 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1024 return 0;
1025 }
1026 }
1027 }
1028 }
1029 } else {
1030 if (EVP_MD_CTX_get0_md(s->read_hash)) {
1031 int n = EVP_MD_CTX_get_size(s->read_hash);
1032 if (!ossl_assert(n >= 0)) {
1033 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1034 return 0;
1035 }
1036 }
1037 ds = s->enc_read_ctx;
1038 if (s->enc_read_ctx == NULL)
1039 enc = NULL;
1040 else
1041 enc = EVP_CIPHER_CTX_get0_cipher(s->enc_read_ctx);
1042 }
1043
1044 if ((s->session == NULL) || (ds == NULL) || (enc == NULL)) {
1045 for (ctr = 0; ctr < n_recs; ctr++) {
1046 memmove(recs[ctr].data, recs[ctr].input, recs[ctr].length);
1047 recs[ctr].input = recs[ctr].data;
1048 }
1049 } else {
1050 int provided = (EVP_CIPHER_get0_provider(enc) != NULL);
1051
1052 bs = EVP_CIPHER_get_block_size(EVP_CIPHER_CTX_get0_cipher(ds));
1053
1054 if (n_recs > 1) {
1055 if ((EVP_CIPHER_get_flags(EVP_CIPHER_CTX_get0_cipher(ds))
1056 & EVP_CIPH_FLAG_PIPELINE) == 0) {
1057 /*
1058 * We shouldn't have been called with pipeline data if the
1059 * cipher doesn't support pipelining
1060 */
1061 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_PIPELINE_FAILURE);
1062 return 0;
1063 }
1064 }
1065 for (ctr = 0; ctr < n_recs; ctr++) {
1066 reclen[ctr] = recs[ctr].length;
1067
1068 if ((EVP_CIPHER_get_flags(EVP_CIPHER_CTX_get0_cipher(ds))
1069 & EVP_CIPH_FLAG_AEAD_CIPHER) != 0) {
1070 unsigned char *seq;
1071
1072 seq = sending ? RECORD_LAYER_get_write_sequence(&s->rlayer)
1073 : RECORD_LAYER_get_read_sequence(&s->rlayer);
1074
1075 if (SSL_IS_DTLS(s)) {
1076 /* DTLS does not support pipelining */
1077 unsigned char dtlsseq[8], *p = dtlsseq;
1078
1079 s2n(sending ? DTLS_RECORD_LAYER_get_w_epoch(&s->rlayer) :
1080 DTLS_RECORD_LAYER_get_r_epoch(&s->rlayer), p);
1081 memcpy(p, &seq[2], 6);
1082 memcpy(buf[ctr], dtlsseq, 8);
1083 } else {
1084 memcpy(buf[ctr], seq, 8);
1085 for (i = 7; i >= 0; i--) { /* increment */
1086 ++seq[i];
1087 if (seq[i] != 0)
1088 break;
1089 }
1090 }
1091
1092 buf[ctr][8] = recs[ctr].type;
1093 buf[ctr][9] = (unsigned char)(s->version >> 8);
1094 buf[ctr][10] = (unsigned char)(s->version);
1095 buf[ctr][11] = (unsigned char)(recs[ctr].length >> 8);
1096 buf[ctr][12] = (unsigned char)(recs[ctr].length & 0xff);
1097 pad = EVP_CIPHER_CTX_ctrl(ds, EVP_CTRL_AEAD_TLS1_AAD,
1098 EVP_AEAD_TLS1_AAD_LEN, buf[ctr]);
1099 if (pad <= 0) {
1100 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1101 return 0;
1102 }
1103
1104 if (sending) {
1105 reclen[ctr] += pad;
1106 recs[ctr].length += pad;
1107 }
1108
1109 } else if ((bs != 1) && sending && !provided) {
1110 /*
1111 * We only do this for legacy ciphers. Provided ciphers add the
1112 * padding on the provider side.
1113 */
1114 padnum = bs - (reclen[ctr] % bs);
1115
1116 /* Add weird padding of up to 256 bytes */
1117
1118 if (padnum > MAX_PADDING) {
1119 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1120 return 0;
1121 }
1122 /* we need to add 'padnum' padding bytes of value padval */
1123 padval = (unsigned char)(padnum - 1);
1124 for (loop = reclen[ctr]; loop < reclen[ctr] + padnum; loop++)
1125 recs[ctr].input[loop] = padval;
1126 reclen[ctr] += padnum;
1127 recs[ctr].length += padnum;
1128 }
1129
1130 if (!sending) {
1131 if (reclen[ctr] == 0 || reclen[ctr] % bs != 0) {
1132 /* Publicly invalid */
1133 return 0;
1134 }
1135 }
1136 }
1137 if (n_recs > 1) {
1138 /* Set the output buffers */
1139 for (ctr = 0; ctr < n_recs; ctr++) {
1140 data[ctr] = recs[ctr].data;
1141 }
1142 if (EVP_CIPHER_CTX_ctrl(ds, EVP_CTRL_SET_PIPELINE_OUTPUT_BUFS,
1143 (int)n_recs, data) <= 0) {
1144 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_PIPELINE_FAILURE);
1145 return 0;
1146 }
1147 /* Set the input buffers */
1148 for (ctr = 0; ctr < n_recs; ctr++) {
1149 data[ctr] = recs[ctr].input;
1150 }
1151 if (EVP_CIPHER_CTX_ctrl(ds, EVP_CTRL_SET_PIPELINE_INPUT_BUFS,
1152 (int)n_recs, data) <= 0
1153 || EVP_CIPHER_CTX_ctrl(ds, EVP_CTRL_SET_PIPELINE_INPUT_LENS,
1154 (int)n_recs, reclen) <= 0) {
1155 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_PIPELINE_FAILURE);
1156 return 0;
1157 }
1158 }
1159
1160 if (!SSL_IS_DTLS(s) && tlstree_enc) {
1161 unsigned char *seq;
1162 int decrement_seq = 0;
1163
1164 /*
1165 * When sending, seq is incremented after MAC calculation.
1166 * So if we are in ETM mode, we use seq 'as is' in the ctrl-function.
1167 * Otherwise we have to decrease it in the implementation
1168 */
1169 if (sending && !SSL_WRITE_ETM(s))
1170 decrement_seq = 1;
1171
1172 seq = sending ? RECORD_LAYER_get_write_sequence(&s->rlayer)
1173 : RECORD_LAYER_get_read_sequence(&s->rlayer);
1174 if (EVP_CIPHER_CTX_ctrl(ds, EVP_CTRL_TLSTREE, decrement_seq, seq) <= 0) {
1175 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1176 return 0;
1177 }
1178 }
1179
1180 if (provided) {
1181 int outlen;
1182
1183 /* Provided cipher - we do not support pipelining on this path */
1184 if (n_recs > 1) {
1185 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
1186 return 0;
1187 }
1188
1189 if (!EVP_CipherUpdate(ds, recs[0].data, &outlen, recs[0].input,
1190 (unsigned int)reclen[0]))
1191 return 0;
1192 recs[0].length = outlen;
1193
1194 /*
1195 * The length returned from EVP_CipherUpdate above is the actual
1196 * payload length. We need to adjust the data/input ptr to skip over
1197 * any explicit IV
1198 */
1199 if (!sending) {
1200 if (EVP_CIPHER_get_mode(enc) == EVP_CIPH_GCM_MODE) {
1201 recs[0].data += EVP_GCM_TLS_EXPLICIT_IV_LEN;
1202 recs[0].input += EVP_GCM_TLS_EXPLICIT_IV_LEN;
1203 } else if (EVP_CIPHER_get_mode(enc) == EVP_CIPH_CCM_MODE) {
1204 recs[0].data += EVP_CCM_TLS_EXPLICIT_IV_LEN;
1205 recs[0].input += EVP_CCM_TLS_EXPLICIT_IV_LEN;
1206 } else if (bs != 1 && SSL_USE_EXPLICIT_IV(s)) {
1207 recs[0].data += bs;
1208 recs[0].input += bs;
1209 recs[0].orig_len -= bs;
1210 }
1211
1212 /* Now get a pointer to the MAC (if applicable) */
1213 if (macs != NULL) {
1214 OSSL_PARAM params[2], *p = params;
1215
1216 /* Get the MAC */
1217 macs[0].alloced = 0;
1218
1219 *p++ = OSSL_PARAM_construct_octet_ptr(OSSL_CIPHER_PARAM_TLS_MAC,
1220 (void **)&macs[0].mac,
1221 macsize);
1222 *p = OSSL_PARAM_construct_end();
1223
1224 if (!EVP_CIPHER_CTX_get_params(ds, params)) {
1225 /* Shouldn't normally happen */
1226 SSLfatal(s, SSL_AD_INTERNAL_ERROR,
1227 ERR_R_INTERNAL_ERROR);
1228 return 0;
1229 }
1230 }
1231 }
1232 } else {
1233 /* Legacy cipher */
1234
1235 tmpr = EVP_Cipher(ds, recs[0].data, recs[0].input,
1236 (unsigned int)reclen[0]);
1237 if ((EVP_CIPHER_get_flags(EVP_CIPHER_CTX_get0_cipher(ds))
1238 & EVP_CIPH_FLAG_CUSTOM_CIPHER) != 0
1239 ? (tmpr < 0)
1240 : (tmpr == 0)) {
1241 /* AEAD can fail to verify MAC */
1242 return 0;
1243 }
1244
1245 if (!sending) {
1246 for (ctr = 0; ctr < n_recs; ctr++) {
1247 /* Adjust the record to remove the explicit IV/MAC/Tag */
1248 if (EVP_CIPHER_get_mode(enc) == EVP_CIPH_GCM_MODE) {
1249 recs[ctr].data += EVP_GCM_TLS_EXPLICIT_IV_LEN;
1250 recs[ctr].input += EVP_GCM_TLS_EXPLICIT_IV_LEN;
1251 recs[ctr].length -= EVP_GCM_TLS_EXPLICIT_IV_LEN;
1252 } else if (EVP_CIPHER_get_mode(enc) == EVP_CIPH_CCM_MODE) {
1253 recs[ctr].data += EVP_CCM_TLS_EXPLICIT_IV_LEN;
1254 recs[ctr].input += EVP_CCM_TLS_EXPLICIT_IV_LEN;
1255 recs[ctr].length -= EVP_CCM_TLS_EXPLICIT_IV_LEN;
1256 } else if (bs != 1 && SSL_USE_EXPLICIT_IV(s)) {
1257 if (recs[ctr].length < bs)
1258 return 0;
1259 recs[ctr].data += bs;
1260 recs[ctr].input += bs;
1261 recs[ctr].length -= bs;
1262 recs[ctr].orig_len -= bs;
1263 }
1264
1265 /*
1266 * If using Mac-then-encrypt, then this will succeed but
1267 * with a random MAC if padding is invalid
1268 */
1269 if (!tls1_cbc_remove_padding_and_mac(&recs[ctr].length,
1270 recs[ctr].orig_len,
1271 recs[ctr].data,
1272 (macs != NULL) ? &macs[ctr].mac : NULL,
1273 (macs != NULL) ? &macs[ctr].alloced
1274 : NULL,
1275 bs,
1276 pad ? (size_t)pad : macsize,
1277 (EVP_CIPHER_get_flags(enc)
1278 & EVP_CIPH_FLAG_AEAD_CIPHER) != 0,
1279 s->ctx->libctx))
1280 return 0;
1281 }
1282 }
1283 }
1284 }
1285 return 1;
1286 }
1287
1288 /*
1289 * ssl3_cbc_record_digest_supported returns 1 iff |ctx| uses a hash function
1290 * which ssl3_cbc_digest_record supports.
1291 */
ssl3_cbc_record_digest_supported(const EVP_MD_CTX * ctx)1292 char ssl3_cbc_record_digest_supported(const EVP_MD_CTX *ctx)
1293 {
1294 switch (EVP_MD_CTX_get_type(ctx)) {
1295 case NID_md5:
1296 case NID_sha1:
1297 case NID_sha224:
1298 case NID_sha256:
1299 case NID_sha384:
1300 case NID_sha512:
1301 return 1;
1302 default:
1303 return 0;
1304 }
1305 }
1306
n_ssl3_mac(SSL * ssl,SSL3_RECORD * rec,unsigned char * md,int sending)1307 int n_ssl3_mac(SSL *ssl, SSL3_RECORD *rec, unsigned char *md, int sending)
1308 {
1309 unsigned char *mac_sec, *seq;
1310 const EVP_MD_CTX *hash;
1311 unsigned char *p, rec_char;
1312 size_t md_size;
1313 size_t npad;
1314 int t;
1315
1316 if (sending) {
1317 mac_sec = &(ssl->s3.write_mac_secret[0]);
1318 seq = RECORD_LAYER_get_write_sequence(&ssl->rlayer);
1319 hash = ssl->write_hash;
1320 } else {
1321 mac_sec = &(ssl->s3.read_mac_secret[0]);
1322 seq = RECORD_LAYER_get_read_sequence(&ssl->rlayer);
1323 hash = ssl->read_hash;
1324 }
1325
1326 t = EVP_MD_CTX_get_size(hash);
1327 if (t <= 0)
1328 return 0;
1329 md_size = t;
1330 npad = (48 / md_size) * md_size;
1331
1332 if (!sending
1333 && EVP_CIPHER_CTX_get_mode(ssl->enc_read_ctx) == EVP_CIPH_CBC_MODE
1334 && ssl3_cbc_record_digest_supported(hash)) {
1335 #ifdef OPENSSL_NO_DEPRECATED_3_0
1336 return 0;
1337 #else
1338 /*
1339 * This is a CBC-encrypted record. We must avoid leaking any
1340 * timing-side channel information about how many blocks of data we
1341 * are hashing because that gives an attacker a timing-oracle.
1342 */
1343
1344 /*-
1345 * npad is, at most, 48 bytes and that's with MD5:
1346 * 16 + 48 + 8 (sequence bytes) + 1 + 2 = 75.
1347 *
1348 * With SHA-1 (the largest hash speced for SSLv3) the hash size
1349 * goes up 4, but npad goes down by 8, resulting in a smaller
1350 * total size.
1351 */
1352 unsigned char header[75];
1353 size_t j = 0;
1354 memcpy(header + j, mac_sec, md_size);
1355 j += md_size;
1356 memcpy(header + j, ssl3_pad_1, npad);
1357 j += npad;
1358 memcpy(header + j, seq, 8);
1359 j += 8;
1360 header[j++] = rec->type;
1361 header[j++] = (unsigned char)(rec->length >> 8);
1362 header[j++] = (unsigned char)(rec->length & 0xff);
1363
1364 /* Final param == is SSLv3 */
1365 if (ssl3_cbc_digest_record(EVP_MD_CTX_get0_md(hash),
1366 md, &md_size,
1367 header, rec->input,
1368 rec->length, rec->orig_len,
1369 mac_sec, md_size, 1) <= 0)
1370 return 0;
1371 #endif
1372 } else {
1373 unsigned int md_size_u;
1374 /* Chop the digest off the end :-) */
1375 EVP_MD_CTX *md_ctx = EVP_MD_CTX_new();
1376
1377 if (md_ctx == NULL)
1378 return 0;
1379
1380 rec_char = rec->type;
1381 p = md;
1382 s2n(rec->length, p);
1383 if (EVP_MD_CTX_copy_ex(md_ctx, hash) <= 0
1384 || EVP_DigestUpdate(md_ctx, mac_sec, md_size) <= 0
1385 || EVP_DigestUpdate(md_ctx, ssl3_pad_1, npad) <= 0
1386 || EVP_DigestUpdate(md_ctx, seq, 8) <= 0
1387 || EVP_DigestUpdate(md_ctx, &rec_char, 1) <= 0
1388 || EVP_DigestUpdate(md_ctx, md, 2) <= 0
1389 || EVP_DigestUpdate(md_ctx, rec->input, rec->length) <= 0
1390 || EVP_DigestFinal_ex(md_ctx, md, NULL) <= 0
1391 || EVP_MD_CTX_copy_ex(md_ctx, hash) <= 0
1392 || EVP_DigestUpdate(md_ctx, mac_sec, md_size) <= 0
1393 || EVP_DigestUpdate(md_ctx, ssl3_pad_2, npad) <= 0
1394 || EVP_DigestUpdate(md_ctx, md, md_size) <= 0
1395 || EVP_DigestFinal_ex(md_ctx, md, &md_size_u) <= 0) {
1396 EVP_MD_CTX_free(md_ctx);
1397 return 0;
1398 }
1399
1400 EVP_MD_CTX_free(md_ctx);
1401 }
1402
1403 ssl3_record_sequence_update(seq);
1404 return 1;
1405 }
1406
tls1_mac(SSL * ssl,SSL3_RECORD * rec,unsigned char * md,int sending)1407 int tls1_mac(SSL *ssl, SSL3_RECORD *rec, unsigned char *md, int sending)
1408 {
1409 unsigned char *seq;
1410 EVP_MD_CTX *hash;
1411 size_t md_size;
1412 int i;
1413 EVP_MD_CTX *hmac = NULL, *mac_ctx;
1414 unsigned char header[13];
1415 int stream_mac = sending ? (ssl->mac_flags & SSL_MAC_FLAG_WRITE_MAC_STREAM)
1416 : (ssl->mac_flags & SSL_MAC_FLAG_READ_MAC_STREAM);
1417 int tlstree_mac = sending ? (ssl->mac_flags & SSL_MAC_FLAG_WRITE_MAC_TLSTREE)
1418 : (ssl->mac_flags & SSL_MAC_FLAG_READ_MAC_TLSTREE);
1419 int t;
1420 int ret = 0;
1421
1422 if (sending) {
1423 seq = RECORD_LAYER_get_write_sequence(&ssl->rlayer);
1424 hash = ssl->write_hash;
1425 } else {
1426 seq = RECORD_LAYER_get_read_sequence(&ssl->rlayer);
1427 hash = ssl->read_hash;
1428 }
1429
1430 t = EVP_MD_CTX_get_size(hash);
1431 if (!ossl_assert(t >= 0))
1432 return 0;
1433 md_size = t;
1434
1435 /* I should fix this up TLS TLS TLS TLS TLS XXXXXXXX */
1436 if (stream_mac) {
1437 mac_ctx = hash;
1438 } else {
1439 hmac = EVP_MD_CTX_new();
1440 if (hmac == NULL || !EVP_MD_CTX_copy(hmac, hash)) {
1441 goto end;
1442 }
1443 mac_ctx = hmac;
1444 }
1445
1446 if (!SSL_IS_DTLS(ssl) && tlstree_mac && EVP_MD_CTX_ctrl(mac_ctx, EVP_MD_CTRL_TLSTREE, 0, seq) <= 0) {
1447 goto end;
1448 }
1449
1450 if (SSL_IS_DTLS(ssl)) {
1451 unsigned char dtlsseq[8], *p = dtlsseq;
1452
1453 s2n(sending ? DTLS_RECORD_LAYER_get_w_epoch(&ssl->rlayer) :
1454 DTLS_RECORD_LAYER_get_r_epoch(&ssl->rlayer), p);
1455 memcpy(p, &seq[2], 6);
1456
1457 memcpy(header, dtlsseq, 8);
1458 } else
1459 memcpy(header, seq, 8);
1460
1461 header[8] = rec->type;
1462 header[9] = (unsigned char)(ssl->version >> 8);
1463 header[10] = (unsigned char)(ssl->version);
1464 header[11] = (unsigned char)(rec->length >> 8);
1465 header[12] = (unsigned char)(rec->length & 0xff);
1466
1467 if (!sending && !SSL_READ_ETM(ssl)
1468 && EVP_CIPHER_CTX_get_mode(ssl->enc_read_ctx) == EVP_CIPH_CBC_MODE
1469 && ssl3_cbc_record_digest_supported(mac_ctx)) {
1470 OSSL_PARAM tls_hmac_params[2], *p = tls_hmac_params;
1471
1472 *p++ = OSSL_PARAM_construct_size_t(OSSL_MAC_PARAM_TLS_DATA_SIZE,
1473 &rec->orig_len);
1474 *p++ = OSSL_PARAM_construct_end();
1475
1476 if (!EVP_PKEY_CTX_set_params(EVP_MD_CTX_get_pkey_ctx(mac_ctx),
1477 tls_hmac_params)) {
1478 goto end;
1479 }
1480 }
1481
1482 if (EVP_DigestSignUpdate(mac_ctx, header, sizeof(header)) <= 0
1483 || EVP_DigestSignUpdate(mac_ctx, rec->input, rec->length) <= 0
1484 || EVP_DigestSignFinal(mac_ctx, md, &md_size) <= 0) {
1485 goto end;
1486 }
1487
1488 OSSL_TRACE_BEGIN(TLS) {
1489 BIO_printf(trc_out, "seq:\n");
1490 BIO_dump_indent(trc_out, seq, 8, 4);
1491 BIO_printf(trc_out, "rec:\n");
1492 BIO_dump_indent(trc_out, rec->data, rec->length, 4);
1493 } OSSL_TRACE_END(TLS);
1494
1495 if (!SSL_IS_DTLS(ssl)) {
1496 for (i = 7; i >= 0; i--) {
1497 ++seq[i];
1498 if (seq[i] != 0)
1499 break;
1500 }
1501 }
1502 OSSL_TRACE_BEGIN(TLS) {
1503 BIO_printf(trc_out, "md:\n");
1504 BIO_dump_indent(trc_out, md, md_size, 4);
1505 } OSSL_TRACE_END(TLS);
1506 ret = 1;
1507 end:
1508 EVP_MD_CTX_free(hmac);
1509 return ret;
1510 }
1511
dtls1_process_record(SSL * s,DTLS1_BITMAP * bitmap)1512 int dtls1_process_record(SSL *s, DTLS1_BITMAP *bitmap)
1513 {
1514 int i;
1515 int enc_err;
1516 SSL_SESSION *sess;
1517 SSL3_RECORD *rr;
1518 int imac_size;
1519 size_t mac_size = 0;
1520 unsigned char md[EVP_MAX_MD_SIZE];
1521 size_t max_plain_length = SSL3_RT_MAX_PLAIN_LENGTH;
1522 SSL_MAC_BUF macbuf = { NULL, 0 };
1523 int ret = 0;
1524
1525 rr = RECORD_LAYER_get_rrec(&s->rlayer);
1526 sess = s->session;
1527
1528 /*
1529 * At this point, s->rlayer.packet_length == SSL3_RT_HEADER_LNGTH + rr->length,
1530 * and we have that many bytes in s->rlayer.packet
1531 */
1532 rr->input = &(RECORD_LAYER_get_packet(&s->rlayer)[DTLS1_RT_HEADER_LENGTH]);
1533
1534 /*
1535 * ok, we can now read from 's->rlayer.packet' data into 'rr'. rr->input
1536 * points at rr->length bytes, which need to be copied into rr->data by
1537 * either the decryption or by the decompression. When the data is 'copied'
1538 * into the rr->data buffer, rr->input will be pointed at the new buffer
1539 */
1540
1541 /*
1542 * We now have - encrypted [ MAC [ compressed [ plain ] ] ] rr->length
1543 * bytes of encrypted compressed stuff.
1544 */
1545
1546 /* check is not needed I believe */
1547 if (rr->length > SSL3_RT_MAX_ENCRYPTED_LENGTH) {
1548 SSLfatal(s, SSL_AD_RECORD_OVERFLOW, SSL_R_ENCRYPTED_LENGTH_TOO_LONG);
1549 return 0;
1550 }
1551
1552 /* decrypt in place in 'rr->input' */
1553 rr->data = rr->input;
1554 rr->orig_len = rr->length;
1555
1556 if (s->read_hash != NULL) {
1557 const EVP_MD *tmpmd = EVP_MD_CTX_get0_md(s->read_hash);
1558
1559 if (tmpmd != NULL) {
1560 imac_size = EVP_MD_get_size(tmpmd);
1561 if (!ossl_assert(imac_size >= 0 && imac_size <= EVP_MAX_MD_SIZE)) {
1562 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_EVP_LIB);
1563 return 0;
1564 }
1565 mac_size = (size_t)imac_size;
1566 }
1567 }
1568
1569 if (SSL_READ_ETM(s) && s->read_hash) {
1570 unsigned char *mac;
1571
1572 if (rr->orig_len < mac_size) {
1573 SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_R_LENGTH_TOO_SHORT);
1574 return 0;
1575 }
1576 rr->length -= mac_size;
1577 mac = rr->data + rr->length;
1578 i = s->method->ssl3_enc->mac(s, rr, md, 0 /* not send */ );
1579 if (i == 0 || CRYPTO_memcmp(md, mac, (size_t)mac_size) != 0) {
1580 SSLfatal(s, SSL_AD_BAD_RECORD_MAC,
1581 SSL_R_DECRYPTION_FAILED_OR_BAD_RECORD_MAC);
1582 return 0;
1583 }
1584 /*
1585 * We've handled the mac now - there is no MAC inside the encrypted
1586 * record
1587 */
1588 mac_size = 0;
1589 }
1590
1591 /*
1592 * Set a mark around the packet decryption attempt. This is DTLS, so
1593 * bad packets are just ignored, and we don't want to leave stray
1594 * errors in the queue from processing bogus junk that we ignored.
1595 */
1596 ERR_set_mark();
1597 enc_err = s->method->ssl3_enc->enc(s, rr, 1, 0, &macbuf, mac_size);
1598
1599 /*-
1600 * enc_err is:
1601 * 0: if the record is publicly invalid, or an internal error, or AEAD
1602 * decryption failed, or ETM decryption failed.
1603 * 1: Success or MTE decryption failed (MAC will be randomised)
1604 */
1605 if (enc_err == 0) {
1606 ERR_pop_to_mark();
1607 if (ossl_statem_in_error(s)) {
1608 /* SSLfatal() got called */
1609 goto end;
1610 }
1611 /* For DTLS we simply ignore bad packets. */
1612 rr->length = 0;
1613 RECORD_LAYER_reset_packet_length(&s->rlayer);
1614 goto end;
1615 }
1616 ERR_clear_last_mark();
1617 OSSL_TRACE_BEGIN(TLS) {
1618 BIO_printf(trc_out, "dec %zd\n", rr->length);
1619 BIO_dump_indent(trc_out, rr->data, rr->length, 4);
1620 } OSSL_TRACE_END(TLS);
1621
1622 /* r->length is now the compressed data plus mac */
1623 if ((sess != NULL)
1624 && !SSL_READ_ETM(s)
1625 && (s->enc_read_ctx != NULL)
1626 && (EVP_MD_CTX_get0_md(s->read_hash) != NULL)) {
1627 /* s->read_hash != NULL => mac_size != -1 */
1628
1629 i = s->method->ssl3_enc->mac(s, rr, md, 0 /* not send */ );
1630 if (i == 0 || macbuf.mac == NULL
1631 || CRYPTO_memcmp(md, macbuf.mac, mac_size) != 0)
1632 enc_err = 0;
1633 if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH + mac_size)
1634 enc_err = 0;
1635 }
1636
1637 if (enc_err == 0) {
1638 /* decryption failed, silently discard message */
1639 rr->length = 0;
1640 RECORD_LAYER_reset_packet_length(&s->rlayer);
1641 goto end;
1642 }
1643
1644 /* r->length is now just compressed */
1645 if (s->expand != NULL) {
1646 if (rr->length > SSL3_RT_MAX_COMPRESSED_LENGTH) {
1647 SSLfatal(s, SSL_AD_RECORD_OVERFLOW,
1648 SSL_R_COMPRESSED_LENGTH_TOO_LONG);
1649 goto end;
1650 }
1651 if (!ssl3_do_uncompress(s, rr)) {
1652 SSLfatal(s, SSL_AD_DECOMPRESSION_FAILURE, SSL_R_BAD_DECOMPRESSION);
1653 goto end;
1654 }
1655 }
1656
1657 /* use current Max Fragment Length setting if applicable */
1658 if (s->session != NULL && USE_MAX_FRAGMENT_LENGTH_EXT(s->session))
1659 max_plain_length = GET_MAX_FRAGMENT_LENGTH(s->session);
1660
1661 /* send overflow if the plaintext is too long now it has passed MAC */
1662 if (rr->length > max_plain_length) {
1663 SSLfatal(s, SSL_AD_RECORD_OVERFLOW, SSL_R_DATA_LENGTH_TOO_LONG);
1664 goto end;
1665 }
1666
1667 rr->off = 0;
1668 /*-
1669 * So at this point the following is true
1670 * ssl->s3.rrec.type is the type of record
1671 * ssl->s3.rrec.length == number of bytes in record
1672 * ssl->s3.rrec.off == offset to first valid byte
1673 * ssl->s3.rrec.data == where to take bytes from, increment
1674 * after use :-).
1675 */
1676
1677 /* we have pulled in a full packet so zero things */
1678 RECORD_LAYER_reset_packet_length(&s->rlayer);
1679
1680 /* Mark receipt of record. */
1681 dtls1_record_bitmap_update(s, bitmap);
1682
1683 ret = 1;
1684 end:
1685 if (macbuf.alloced)
1686 OPENSSL_free(macbuf.mac);
1687 return ret;
1688 }
1689
1690 /*
1691 * Retrieve a buffered record that belongs to the current epoch, i.e. processed
1692 */
1693 #define dtls1_get_processed_record(s) \
1694 dtls1_retrieve_buffered_record((s), \
1695 &(DTLS_RECORD_LAYER_get_processed_rcds(&s->rlayer)))
1696
1697 /*-
1698 * Call this to get a new input record.
1699 * It will return <= 0 if more data is needed, normally due to an error
1700 * or non-blocking IO.
1701 * When it finishes, one packet has been decoded and can be found in
1702 * ssl->s3.rrec.type - is the type of record
1703 * ssl->s3.rrec.data - data
1704 * ssl->s3.rrec.length - number of bytes
1705 */
1706 /* used only by dtls1_read_bytes */
dtls1_get_record(SSL * s)1707 int dtls1_get_record(SSL *s)
1708 {
1709 int ssl_major, ssl_minor;
1710 int rret;
1711 size_t more, n;
1712 SSL3_RECORD *rr;
1713 unsigned char *p = NULL;
1714 unsigned short version;
1715 DTLS1_BITMAP *bitmap;
1716 unsigned int is_next_epoch;
1717
1718 rr = RECORD_LAYER_get_rrec(&s->rlayer);
1719
1720 again:
1721 /*
1722 * The epoch may have changed. If so, process all the pending records.
1723 * This is a non-blocking operation.
1724 */
1725 if (!dtls1_process_buffered_records(s)) {
1726 /* SSLfatal() already called */
1727 return -1;
1728 }
1729
1730 /* if we're renegotiating, then there may be buffered records */
1731 if (dtls1_get_processed_record(s))
1732 return 1;
1733
1734 /* get something from the wire */
1735
1736 /* check if we have the header */
1737 if ((RECORD_LAYER_get_rstate(&s->rlayer) != SSL_ST_READ_BODY) ||
1738 (RECORD_LAYER_get_packet_length(&s->rlayer) < DTLS1_RT_HEADER_LENGTH)) {
1739 rret = ssl3_read_n(s, DTLS1_RT_HEADER_LENGTH,
1740 SSL3_BUFFER_get_len(&s->rlayer.rbuf), 0, 1, &n);
1741 /* read timeout is handled by dtls1_read_bytes */
1742 if (rret <= 0) {
1743 /* SSLfatal() already called if appropriate */
1744 return rret; /* error or non-blocking */
1745 }
1746
1747 /* this packet contained a partial record, dump it */
1748 if (RECORD_LAYER_get_packet_length(&s->rlayer) !=
1749 DTLS1_RT_HEADER_LENGTH) {
1750 RECORD_LAYER_reset_packet_length(&s->rlayer);
1751 goto again;
1752 }
1753
1754 RECORD_LAYER_set_rstate(&s->rlayer, SSL_ST_READ_BODY);
1755
1756 p = RECORD_LAYER_get_packet(&s->rlayer);
1757
1758 if (s->msg_callback)
1759 s->msg_callback(0, 0, SSL3_RT_HEADER, p, DTLS1_RT_HEADER_LENGTH,
1760 s, s->msg_callback_arg);
1761
1762 /* Pull apart the header into the DTLS1_RECORD */
1763 rr->type = *(p++);
1764 ssl_major = *(p++);
1765 ssl_minor = *(p++);
1766 version = (ssl_major << 8) | ssl_minor;
1767
1768 /* sequence number is 64 bits, with top 2 bytes = epoch */
1769 n2s(p, rr->epoch);
1770
1771 memcpy(&(RECORD_LAYER_get_read_sequence(&s->rlayer)[2]), p, 6);
1772 p += 6;
1773
1774 n2s(p, rr->length);
1775 rr->read = 0;
1776
1777 /*
1778 * Lets check the version. We tolerate alerts that don't have the exact
1779 * version number (e.g. because of protocol version errors)
1780 */
1781 if (!s->first_packet && rr->type != SSL3_RT_ALERT) {
1782 if (version != s->version) {
1783 /* unexpected version, silently discard */
1784 rr->length = 0;
1785 rr->read = 1;
1786 RECORD_LAYER_reset_packet_length(&s->rlayer);
1787 goto again;
1788 }
1789 }
1790
1791 if ((version & 0xff00) != (s->version & 0xff00)) {
1792 /* wrong version, silently discard record */
1793 rr->length = 0;
1794 rr->read = 1;
1795 RECORD_LAYER_reset_packet_length(&s->rlayer);
1796 goto again;
1797 }
1798
1799 if (rr->length > SSL3_RT_MAX_ENCRYPTED_LENGTH) {
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 /* If received packet overflows own-client Max Fragment Length setting */
1808 if (s->session != NULL && USE_MAX_FRAGMENT_LENGTH_EXT(s->session)
1809 && rr->length > GET_MAX_FRAGMENT_LENGTH(s->session) + SSL3_RT_MAX_ENCRYPTED_OVERHEAD) {
1810 /* record too long, silently discard it */
1811 rr->length = 0;
1812 rr->read = 1;
1813 RECORD_LAYER_reset_packet_length(&s->rlayer);
1814 goto again;
1815 }
1816
1817 /* now s->rlayer.rstate == SSL_ST_READ_BODY */
1818 }
1819
1820 /* s->rlayer.rstate == SSL_ST_READ_BODY, get and decode the data */
1821
1822 if (rr->length >
1823 RECORD_LAYER_get_packet_length(&s->rlayer) - DTLS1_RT_HEADER_LENGTH) {
1824 /* now s->rlayer.packet_length == DTLS1_RT_HEADER_LENGTH */
1825 more = rr->length;
1826 rret = ssl3_read_n(s, more, more, 1, 1, &n);
1827 /* this packet contained a partial record, dump it */
1828 if (rret <= 0 || n != more) {
1829 if (ossl_statem_in_error(s)) {
1830 /* ssl3_read_n() called SSLfatal() */
1831 return -1;
1832 }
1833 rr->length = 0;
1834 rr->read = 1;
1835 RECORD_LAYER_reset_packet_length(&s->rlayer);
1836 goto again;
1837 }
1838
1839 /*
1840 * now n == rr->length, and s->rlayer.packet_length ==
1841 * DTLS1_RT_HEADER_LENGTH + rr->length
1842 */
1843 }
1844 /* set state for later operations */
1845 RECORD_LAYER_set_rstate(&s->rlayer, SSL_ST_READ_HEADER);
1846
1847 /* match epochs. NULL means the packet is dropped on the floor */
1848 bitmap = dtls1_get_bitmap(s, rr, &is_next_epoch);
1849 if (bitmap == NULL) {
1850 rr->length = 0;
1851 RECORD_LAYER_reset_packet_length(&s->rlayer); /* dump this record */
1852 goto again; /* get another record */
1853 }
1854 #ifndef OPENSSL_NO_SCTP
1855 /* Only do replay check if no SCTP bio */
1856 if (!BIO_dgram_is_sctp(SSL_get_rbio(s))) {
1857 #endif
1858 /* Check whether this is a repeat, or aged record. */
1859 if (!dtls1_record_replay_check(s, bitmap)) {
1860 rr->length = 0;
1861 rr->read = 1;
1862 RECORD_LAYER_reset_packet_length(&s->rlayer); /* dump this record */
1863 goto again; /* get another record */
1864 }
1865 #ifndef OPENSSL_NO_SCTP
1866 }
1867 #endif
1868
1869 /* just read a 0 length packet */
1870 if (rr->length == 0) {
1871 rr->read = 1;
1872 goto again;
1873 }
1874
1875 /*
1876 * If this record is from the next epoch (either HM or ALERT), and a
1877 * handshake is currently in progress, buffer it since it cannot be
1878 * processed at this time.
1879 */
1880 if (is_next_epoch) {
1881 if ((SSL_in_init(s) || ossl_statem_get_in_handshake(s))) {
1882 if (dtls1_buffer_record (s,
1883 &(DTLS_RECORD_LAYER_get_unprocessed_rcds(&s->rlayer)),
1884 rr->seq_num) < 0) {
1885 /* SSLfatal() already called */
1886 return -1;
1887 }
1888 }
1889 rr->length = 0;
1890 rr->read = 1;
1891 RECORD_LAYER_reset_packet_length(&s->rlayer);
1892 goto again;
1893 }
1894
1895 if (!dtls1_process_record(s, bitmap)) {
1896 if (ossl_statem_in_error(s)) {
1897 /* dtls1_process_record() called SSLfatal */
1898 return -1;
1899 }
1900 rr->length = 0;
1901 rr->read = 1;
1902 RECORD_LAYER_reset_packet_length(&s->rlayer); /* dump this record */
1903 goto again; /* get another record */
1904 }
1905
1906 return 1;
1907
1908 }
1909
dtls_buffer_listen_record(SSL * s,size_t len,unsigned char * seq,size_t off)1910 int dtls_buffer_listen_record(SSL *s, size_t len, unsigned char *seq, size_t off)
1911 {
1912 SSL3_RECORD *rr;
1913
1914 rr = RECORD_LAYER_get_rrec(&s->rlayer);
1915 memset(rr, 0, sizeof(SSL3_RECORD));
1916
1917 rr->length = len;
1918 rr->type = SSL3_RT_HANDSHAKE;
1919 memcpy(rr->seq_num, seq, sizeof(rr->seq_num));
1920 rr->off = off;
1921
1922 s->rlayer.packet = RECORD_LAYER_get_rbuf(&s->rlayer)->buf;
1923 s->rlayer.packet_length = DTLS1_RT_HEADER_LENGTH + len;
1924 rr->data = s->rlayer.packet + DTLS1_RT_HEADER_LENGTH;
1925
1926 if (dtls1_buffer_record(s, &(s->rlayer.d->processed_rcds),
1927 SSL3_RECORD_get_seq_num(s->rlayer.rrec)) <= 0) {
1928 /* SSLfatal() already called */
1929 return 0;
1930 }
1931
1932 return 1;
1933 }
1934