1 /*
2 * Copyright 2005-2022 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 <stdio.h>
11 #include <errno.h>
12 #include "../ssl_local.h"
13 #include <openssl/evp.h>
14 #include <openssl/buffer.h>
15 #include "record_local.h"
16 #include "internal/packet.h"
17 #include "internal/cryptlib.h"
18
DTLS_RECORD_LAYER_new(RECORD_LAYER * rl)19 int DTLS_RECORD_LAYER_new(RECORD_LAYER *rl)
20 {
21 DTLS_RECORD_LAYER *d;
22
23 if ((d = OPENSSL_malloc(sizeof(*d))) == NULL) {
24 ERR_raise(ERR_LIB_SSL, ERR_R_MALLOC_FAILURE);
25 return 0;
26 }
27
28 rl->d = d;
29
30 d->unprocessed_rcds.q = pqueue_new();
31 d->processed_rcds.q = pqueue_new();
32 d->buffered_app_data.q = pqueue_new();
33
34 if (d->unprocessed_rcds.q == NULL || d->processed_rcds.q == NULL
35 || d->buffered_app_data.q == NULL) {
36 pqueue_free(d->unprocessed_rcds.q);
37 pqueue_free(d->processed_rcds.q);
38 pqueue_free(d->buffered_app_data.q);
39 OPENSSL_free(d);
40 rl->d = NULL;
41 return 0;
42 }
43
44 return 1;
45 }
46
DTLS_RECORD_LAYER_free(RECORD_LAYER * rl)47 void DTLS_RECORD_LAYER_free(RECORD_LAYER *rl)
48 {
49 if (rl->d == NULL)
50 return;
51
52 DTLS_RECORD_LAYER_clear(rl);
53 pqueue_free(rl->d->unprocessed_rcds.q);
54 pqueue_free(rl->d->processed_rcds.q);
55 pqueue_free(rl->d->buffered_app_data.q);
56 OPENSSL_free(rl->d);
57 rl->d = NULL;
58 }
59
DTLS_RECORD_LAYER_clear(RECORD_LAYER * rl)60 void DTLS_RECORD_LAYER_clear(RECORD_LAYER *rl)
61 {
62 DTLS_RECORD_LAYER *d;
63 pitem *item = NULL;
64 DTLS1_RECORD_DATA *rdata;
65 pqueue *unprocessed_rcds;
66 pqueue *processed_rcds;
67 pqueue *buffered_app_data;
68
69 d = rl->d;
70
71 while ((item = pqueue_pop(d->unprocessed_rcds.q)) != NULL) {
72 rdata = (DTLS1_RECORD_DATA *)item->data;
73 OPENSSL_free(rdata->rbuf.buf);
74 OPENSSL_free(item->data);
75 pitem_free(item);
76 }
77
78 while ((item = pqueue_pop(d->processed_rcds.q)) != NULL) {
79 rdata = (DTLS1_RECORD_DATA *)item->data;
80 if (rl->s->options & SSL_OP_CLEANSE_PLAINTEXT)
81 OPENSSL_cleanse(rdata->rbuf.buf, rdata->rbuf.len);
82 OPENSSL_free(rdata->rbuf.buf);
83 OPENSSL_free(item->data);
84 pitem_free(item);
85 }
86
87 while ((item = pqueue_pop(d->buffered_app_data.q)) != NULL) {
88 rdata = (DTLS1_RECORD_DATA *)item->data;
89 if (rl->s->options & SSL_OP_CLEANSE_PLAINTEXT)
90 OPENSSL_cleanse(rdata->rbuf.buf, rdata->rbuf.len);
91 OPENSSL_free(rdata->rbuf.buf);
92 OPENSSL_free(item->data);
93 pitem_free(item);
94 }
95
96 unprocessed_rcds = d->unprocessed_rcds.q;
97 processed_rcds = d->processed_rcds.q;
98 buffered_app_data = d->buffered_app_data.q;
99 memset(d, 0, sizeof(*d));
100 d->unprocessed_rcds.q = unprocessed_rcds;
101 d->processed_rcds.q = processed_rcds;
102 d->buffered_app_data.q = buffered_app_data;
103 }
104
DTLS_RECORD_LAYER_set_saved_w_epoch(RECORD_LAYER * rl,unsigned short e)105 void DTLS_RECORD_LAYER_set_saved_w_epoch(RECORD_LAYER *rl, unsigned short e)
106 {
107 if (e == rl->d->w_epoch - 1) {
108 memcpy(rl->d->curr_write_sequence,
109 rl->write_sequence, sizeof(rl->write_sequence));
110 memcpy(rl->write_sequence,
111 rl->d->last_write_sequence, sizeof(rl->write_sequence));
112 } else if (e == rl->d->w_epoch + 1) {
113 memcpy(rl->d->last_write_sequence,
114 rl->write_sequence, sizeof(unsigned char[8]));
115 memcpy(rl->write_sequence,
116 rl->d->curr_write_sequence, sizeof(rl->write_sequence));
117 }
118 rl->d->w_epoch = e;
119 }
120
DTLS_RECORD_LAYER_set_write_sequence(RECORD_LAYER * rl,unsigned char * seq)121 void DTLS_RECORD_LAYER_set_write_sequence(RECORD_LAYER *rl, unsigned char *seq)
122 {
123 memcpy(rl->write_sequence, seq, SEQ_NUM_SIZE);
124 }
125
126 /* copy buffered record into SSL structure */
dtls1_copy_record(SSL * s,pitem * item)127 static int dtls1_copy_record(SSL *s, pitem *item)
128 {
129 DTLS1_RECORD_DATA *rdata;
130
131 rdata = (DTLS1_RECORD_DATA *)item->data;
132
133 SSL3_BUFFER_release(&s->rlayer.rbuf);
134
135 s->rlayer.packet = rdata->packet;
136 s->rlayer.packet_length = rdata->packet_length;
137 memcpy(&s->rlayer.rbuf, &(rdata->rbuf), sizeof(SSL3_BUFFER));
138 memcpy(&s->rlayer.rrec, &(rdata->rrec), sizeof(SSL3_RECORD));
139
140 /* Set proper sequence number for mac calculation */
141 memcpy(&(s->rlayer.read_sequence[2]), &(rdata->packet[5]), 6);
142
143 return 1;
144 }
145
dtls1_buffer_record(SSL * s,record_pqueue * queue,unsigned char * priority)146 int dtls1_buffer_record(SSL *s, record_pqueue *queue, unsigned char *priority)
147 {
148 DTLS1_RECORD_DATA *rdata;
149 pitem *item;
150
151 /* Limit the size of the queue to prevent DOS attacks */
152 if (pqueue_size(queue->q) >= 100)
153 return 0;
154
155 rdata = OPENSSL_malloc(sizeof(*rdata));
156 item = pitem_new(priority, rdata);
157 if (rdata == NULL || item == NULL) {
158 OPENSSL_free(rdata);
159 pitem_free(item);
160 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
161 return -1;
162 }
163
164 rdata->packet = s->rlayer.packet;
165 rdata->packet_length = s->rlayer.packet_length;
166 memcpy(&(rdata->rbuf), &s->rlayer.rbuf, sizeof(SSL3_BUFFER));
167 memcpy(&(rdata->rrec), &s->rlayer.rrec, sizeof(SSL3_RECORD));
168
169 item->data = rdata;
170
171 #ifndef OPENSSL_NO_SCTP
172 /* Store bio_dgram_sctp_rcvinfo struct */
173 if (BIO_dgram_is_sctp(SSL_get_rbio(s)) &&
174 (SSL_get_state(s) == TLS_ST_SR_FINISHED
175 || SSL_get_state(s) == TLS_ST_CR_FINISHED)) {
176 BIO_ctrl(SSL_get_rbio(s), BIO_CTRL_DGRAM_SCTP_GET_RCVINFO,
177 sizeof(rdata->recordinfo), &rdata->recordinfo);
178 }
179 #endif
180
181 s->rlayer.packet = NULL;
182 s->rlayer.packet_length = 0;
183 memset(&s->rlayer.rbuf, 0, sizeof(s->rlayer.rbuf));
184 memset(&s->rlayer.rrec, 0, sizeof(s->rlayer.rrec));
185
186 if (!ssl3_setup_buffers(s)) {
187 /* SSLfatal() already called */
188 OPENSSL_free(rdata->rbuf.buf);
189 OPENSSL_free(rdata);
190 pitem_free(item);
191 return -1;
192 }
193
194 if (pqueue_insert(queue->q, item) == NULL) {
195 /* Must be a duplicate so ignore it */
196 OPENSSL_free(rdata->rbuf.buf);
197 OPENSSL_free(rdata);
198 pitem_free(item);
199 }
200
201 return 1;
202 }
203
dtls1_retrieve_buffered_record(SSL * s,record_pqueue * queue)204 int dtls1_retrieve_buffered_record(SSL *s, record_pqueue *queue)
205 {
206 pitem *item;
207
208 item = pqueue_pop(queue->q);
209 if (item) {
210 dtls1_copy_record(s, item);
211
212 OPENSSL_free(item->data);
213 pitem_free(item);
214
215 return 1;
216 }
217
218 return 0;
219 }
220
221 /*
222 * retrieve a buffered record that belongs to the new epoch, i.e., not
223 * processed yet
224 */
225 #define dtls1_get_unprocessed_record(s) \
226 dtls1_retrieve_buffered_record((s), \
227 &((s)->rlayer.d->unprocessed_rcds))
228
dtls1_process_buffered_records(SSL * s)229 int dtls1_process_buffered_records(SSL *s)
230 {
231 pitem *item;
232 SSL3_BUFFER *rb;
233 SSL3_RECORD *rr;
234 DTLS1_BITMAP *bitmap;
235 unsigned int is_next_epoch;
236 int replayok = 1;
237
238 item = pqueue_peek(s->rlayer.d->unprocessed_rcds.q);
239 if (item) {
240 /* Check if epoch is current. */
241 if (s->rlayer.d->unprocessed_rcds.epoch != s->rlayer.d->r_epoch)
242 return 1; /* Nothing to do. */
243
244 rr = RECORD_LAYER_get_rrec(&s->rlayer);
245
246 rb = RECORD_LAYER_get_rbuf(&s->rlayer);
247
248 if (SSL3_BUFFER_get_left(rb) > 0) {
249 /*
250 * We've still got data from the current packet to read. There could
251 * be a record from the new epoch in it - so don't overwrite it
252 * with the unprocessed records yet (we'll do it when we've
253 * finished reading the current packet).
254 */
255 return 1;
256 }
257
258 /* Process all the records. */
259 while (pqueue_peek(s->rlayer.d->unprocessed_rcds.q)) {
260 dtls1_get_unprocessed_record(s);
261 bitmap = dtls1_get_bitmap(s, rr, &is_next_epoch);
262 if (bitmap == NULL) {
263 /*
264 * Should not happen. This will only ever be NULL when the
265 * current record is from a different epoch. But that cannot
266 * be the case because we already checked the epoch above
267 */
268 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
269 return 0;
270 }
271 #ifndef OPENSSL_NO_SCTP
272 /* Only do replay check if no SCTP bio */
273 if (!BIO_dgram_is_sctp(SSL_get_rbio(s)))
274 #endif
275 {
276 /*
277 * Check whether this is a repeat, or aged record. We did this
278 * check once already when we first received the record - but
279 * we might have updated the window since then due to
280 * records we subsequently processed.
281 */
282 replayok = dtls1_record_replay_check(s, bitmap);
283 }
284
285 if (!replayok || !dtls1_process_record(s, bitmap)) {
286 if (ossl_statem_in_error(s)) {
287 /* dtls1_process_record called SSLfatal() */
288 return 0;
289 }
290 /* dump this record */
291 rr->length = 0;
292 RECORD_LAYER_reset_packet_length(&s->rlayer);
293 continue;
294 }
295
296 if (dtls1_buffer_record(s, &(s->rlayer.d->processed_rcds),
297 SSL3_RECORD_get_seq_num(s->rlayer.rrec)) < 0) {
298 /* SSLfatal() already called */
299 return 0;
300 }
301 }
302 }
303
304 /*
305 * sync epoch numbers once all the unprocessed records have been
306 * processed
307 */
308 s->rlayer.d->processed_rcds.epoch = s->rlayer.d->r_epoch;
309 s->rlayer.d->unprocessed_rcds.epoch = s->rlayer.d->r_epoch + 1;
310
311 return 1;
312 }
313
314 /*-
315 * Return up to 'len' payload bytes received in 'type' records.
316 * 'type' is one of the following:
317 *
318 * - SSL3_RT_HANDSHAKE (when ssl3_get_message calls us)
319 * - SSL3_RT_APPLICATION_DATA (when ssl3_read calls us)
320 * - 0 (during a shutdown, no data has to be returned)
321 *
322 * If we don't have stored data to work from, read a SSL/TLS record first
323 * (possibly multiple records if we still don't have anything to return).
324 *
325 * This function must handle any surprises the peer may have for us, such as
326 * Alert records (e.g. close_notify) or renegotiation requests. ChangeCipherSpec
327 * messages are treated as if they were handshake messages *if* the |recd_type|
328 * argument is non NULL.
329 * Also if record payloads contain fragments too small to process, we store
330 * them until there is enough for the respective protocol (the record protocol
331 * may use arbitrary fragmentation and even interleaving):
332 * Change cipher spec protocol
333 * just 1 byte needed, no need for keeping anything stored
334 * Alert protocol
335 * 2 bytes needed (AlertLevel, AlertDescription)
336 * Handshake protocol
337 * 4 bytes needed (HandshakeType, uint24 length) -- we just have
338 * to detect unexpected Client Hello and Hello Request messages
339 * here, anything else is handled by higher layers
340 * Application data protocol
341 * none of our business
342 */
dtls1_read_bytes(SSL * s,int type,int * recvd_type,unsigned char * buf,size_t len,int peek,size_t * readbytes)343 int dtls1_read_bytes(SSL *s, int type, int *recvd_type, unsigned char *buf,
344 size_t len, int peek, size_t *readbytes)
345 {
346 int i, j, iret;
347 size_t n;
348 SSL3_RECORD *rr;
349 void (*cb) (const SSL *ssl, int type2, int val) = NULL;
350
351 if (!SSL3_BUFFER_is_initialised(&s->rlayer.rbuf)) {
352 /* Not initialized yet */
353 if (!ssl3_setup_buffers(s)) {
354 /* SSLfatal() already called */
355 return -1;
356 }
357 }
358
359 if ((type && (type != SSL3_RT_APPLICATION_DATA) &&
360 (type != SSL3_RT_HANDSHAKE)) ||
361 (peek && (type != SSL3_RT_APPLICATION_DATA))) {
362 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
363 return -1;
364 }
365
366 if (!ossl_statem_get_in_handshake(s) && SSL_in_init(s)) {
367 /* type == SSL3_RT_APPLICATION_DATA */
368 i = s->handshake_func(s);
369 /* SSLfatal() already called if appropriate */
370 if (i < 0)
371 return i;
372 if (i == 0)
373 return -1;
374 }
375
376 start:
377 s->rwstate = SSL_NOTHING;
378
379 /*-
380 * s->s3.rrec.type - is the type of record
381 * s->s3.rrec.data, - data
382 * s->s3.rrec.off, - offset into 'data' for next read
383 * s->s3.rrec.length, - number of bytes.
384 */
385 rr = s->rlayer.rrec;
386
387 /*
388 * We are not handshaking and have no data yet, so process data buffered
389 * during the last handshake in advance, if any.
390 */
391 if (SSL_is_init_finished(s) && SSL3_RECORD_get_length(rr) == 0) {
392 pitem *item;
393 item = pqueue_pop(s->rlayer.d->buffered_app_data.q);
394 if (item) {
395 #ifndef OPENSSL_NO_SCTP
396 /* Restore bio_dgram_sctp_rcvinfo struct */
397 if (BIO_dgram_is_sctp(SSL_get_rbio(s))) {
398 DTLS1_RECORD_DATA *rdata = (DTLS1_RECORD_DATA *)item->data;
399 BIO_ctrl(SSL_get_rbio(s), BIO_CTRL_DGRAM_SCTP_SET_RCVINFO,
400 sizeof(rdata->recordinfo), &rdata->recordinfo);
401 }
402 #endif
403
404 dtls1_copy_record(s, item);
405
406 OPENSSL_free(item->data);
407 pitem_free(item);
408 }
409 }
410
411 /* Check for timeout */
412 if (dtls1_handle_timeout(s) > 0) {
413 goto start;
414 } else if (ossl_statem_in_error(s)) {
415 /* dtls1_handle_timeout() has failed with a fatal error */
416 return -1;
417 }
418
419 /* get new packet if necessary */
420 if ((SSL3_RECORD_get_length(rr) == 0)
421 || (s->rlayer.rstate == SSL_ST_READ_BODY)) {
422 RECORD_LAYER_set_numrpipes(&s->rlayer, 0);
423 iret = dtls1_get_record(s);
424 if (iret <= 0) {
425 iret = dtls1_read_failed(s, iret);
426 /*
427 * Anything other than a timeout is an error. SSLfatal() already
428 * called if appropriate.
429 */
430 if (iret <= 0)
431 return iret;
432 else
433 goto start;
434 }
435 RECORD_LAYER_set_numrpipes(&s->rlayer, 1);
436 }
437
438 /*
439 * Reset the count of consecutive warning alerts if we've got a non-empty
440 * record that isn't an alert.
441 */
442 if (SSL3_RECORD_get_type(rr) != SSL3_RT_ALERT
443 && SSL3_RECORD_get_length(rr) != 0)
444 s->rlayer.alert_count = 0;
445
446 /* we now have a packet which can be read and processed */
447
448 if (s->s3.change_cipher_spec /* set when we receive ChangeCipherSpec,
449 * reset by ssl3_get_finished */
450 && (SSL3_RECORD_get_type(rr) != SSL3_RT_HANDSHAKE)) {
451 /*
452 * We now have application data between CCS and Finished. Most likely
453 * the packets were reordered on their way, so buffer the application
454 * data for later processing rather than dropping the connection.
455 */
456 if (dtls1_buffer_record(s, &(s->rlayer.d->buffered_app_data),
457 SSL3_RECORD_get_seq_num(rr)) < 0) {
458 /* SSLfatal() already called */
459 return -1;
460 }
461 SSL3_RECORD_set_length(rr, 0);
462 SSL3_RECORD_set_read(rr);
463 goto start;
464 }
465
466 /*
467 * If the other end has shut down, throw anything we read away (even in
468 * 'peek' mode)
469 */
470 if (s->shutdown & SSL_RECEIVED_SHUTDOWN) {
471 SSL3_RECORD_set_length(rr, 0);
472 SSL3_RECORD_set_read(rr);
473 s->rwstate = SSL_NOTHING;
474 return 0;
475 }
476
477 if (type == SSL3_RECORD_get_type(rr)
478 || (SSL3_RECORD_get_type(rr) == SSL3_RT_CHANGE_CIPHER_SPEC
479 && type == SSL3_RT_HANDSHAKE && recvd_type != NULL)) {
480 /*
481 * SSL3_RT_APPLICATION_DATA or
482 * SSL3_RT_HANDSHAKE or
483 * SSL3_RT_CHANGE_CIPHER_SPEC
484 */
485 /*
486 * make sure that we are not getting application data when we are
487 * doing a handshake for the first time
488 */
489 if (SSL_in_init(s) && (type == SSL3_RT_APPLICATION_DATA) &&
490 (s->enc_read_ctx == NULL)) {
491 SSLfatal(s, SSL_AD_UNEXPECTED_MESSAGE,
492 SSL_R_APP_DATA_IN_HANDSHAKE);
493 return -1;
494 }
495
496 if (recvd_type != NULL)
497 *recvd_type = SSL3_RECORD_get_type(rr);
498
499 if (len == 0) {
500 /*
501 * Mark a zero length record as read. This ensures multiple calls to
502 * SSL_read() with a zero length buffer will eventually cause
503 * SSL_pending() to report data as being available.
504 */
505 if (SSL3_RECORD_get_length(rr) == 0)
506 SSL3_RECORD_set_read(rr);
507 return 0;
508 }
509
510 if (len > SSL3_RECORD_get_length(rr))
511 n = SSL3_RECORD_get_length(rr);
512 else
513 n = len;
514
515 memcpy(buf, &(SSL3_RECORD_get_data(rr)[SSL3_RECORD_get_off(rr)]), n);
516 if (peek) {
517 if (SSL3_RECORD_get_length(rr) == 0)
518 SSL3_RECORD_set_read(rr);
519 } else {
520 if (s->options & SSL_OP_CLEANSE_PLAINTEXT)
521 OPENSSL_cleanse(&(SSL3_RECORD_get_data(rr)[SSL3_RECORD_get_off(rr)]), n);
522 SSL3_RECORD_sub_length(rr, n);
523 SSL3_RECORD_add_off(rr, n);
524 if (SSL3_RECORD_get_length(rr) == 0) {
525 s->rlayer.rstate = SSL_ST_READ_HEADER;
526 SSL3_RECORD_set_off(rr, 0);
527 SSL3_RECORD_set_read(rr);
528 }
529 }
530 #ifndef OPENSSL_NO_SCTP
531 /*
532 * We might had to delay a close_notify alert because of reordered
533 * app data. If there was an alert and there is no message to read
534 * anymore, finally set shutdown.
535 */
536 if (BIO_dgram_is_sctp(SSL_get_rbio(s)) &&
537 s->d1->shutdown_received
538 && BIO_dgram_sctp_msg_waiting(SSL_get_rbio(s)) <= 0) {
539 s->shutdown |= SSL_RECEIVED_SHUTDOWN;
540 return 0;
541 }
542 #endif
543 *readbytes = n;
544 return 1;
545 }
546
547 /*
548 * If we get here, then type != rr->type; if we have a handshake message,
549 * then it was unexpected (Hello Request or Client Hello).
550 */
551
552 if (SSL3_RECORD_get_type(rr) == SSL3_RT_ALERT) {
553 unsigned int alert_level, alert_descr;
554 unsigned char *alert_bytes = SSL3_RECORD_get_data(rr)
555 + SSL3_RECORD_get_off(rr);
556 PACKET alert;
557
558 if (!PACKET_buf_init(&alert, alert_bytes, SSL3_RECORD_get_length(rr))
559 || !PACKET_get_1(&alert, &alert_level)
560 || !PACKET_get_1(&alert, &alert_descr)
561 || PACKET_remaining(&alert) != 0) {
562 SSLfatal(s, SSL_AD_UNEXPECTED_MESSAGE, SSL_R_INVALID_ALERT);
563 return -1;
564 }
565
566 if (s->msg_callback)
567 s->msg_callback(0, s->version, SSL3_RT_ALERT, alert_bytes, 2, s,
568 s->msg_callback_arg);
569
570 if (s->info_callback != NULL)
571 cb = s->info_callback;
572 else if (s->ctx->info_callback != NULL)
573 cb = s->ctx->info_callback;
574
575 if (cb != NULL) {
576 j = (alert_level << 8) | alert_descr;
577 cb(s, SSL_CB_READ_ALERT, j);
578 }
579
580 if (alert_level == SSL3_AL_WARNING) {
581 s->s3.warn_alert = alert_descr;
582 SSL3_RECORD_set_read(rr);
583
584 s->rlayer.alert_count++;
585 if (s->rlayer.alert_count == MAX_WARN_ALERT_COUNT) {
586 SSLfatal(s, SSL_AD_UNEXPECTED_MESSAGE,
587 SSL_R_TOO_MANY_WARN_ALERTS);
588 return -1;
589 }
590
591 if (alert_descr == SSL_AD_CLOSE_NOTIFY) {
592 #ifndef OPENSSL_NO_SCTP
593 /*
594 * With SCTP and streams the socket may deliver app data
595 * after a close_notify alert. We have to check this first so
596 * that nothing gets discarded.
597 */
598 if (BIO_dgram_is_sctp(SSL_get_rbio(s)) &&
599 BIO_dgram_sctp_msg_waiting(SSL_get_rbio(s)) > 0) {
600 s->d1->shutdown_received = 1;
601 s->rwstate = SSL_READING;
602 BIO_clear_retry_flags(SSL_get_rbio(s));
603 BIO_set_retry_read(SSL_get_rbio(s));
604 return -1;
605 }
606 #endif
607 s->shutdown |= SSL_RECEIVED_SHUTDOWN;
608 return 0;
609 }
610 } else if (alert_level == SSL3_AL_FATAL) {
611 s->rwstate = SSL_NOTHING;
612 s->s3.fatal_alert = alert_descr;
613 SSLfatal_data(s, SSL_AD_NO_ALERT,
614 SSL_AD_REASON_OFFSET + alert_descr,
615 "SSL alert number %d", alert_descr);
616 s->shutdown |= SSL_RECEIVED_SHUTDOWN;
617 SSL3_RECORD_set_read(rr);
618 SSL_CTX_remove_session(s->session_ctx, s->session);
619 return 0;
620 } else {
621 SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_R_UNKNOWN_ALERT_TYPE);
622 return -1;
623 }
624
625 goto start;
626 }
627
628 if (s->shutdown & SSL_SENT_SHUTDOWN) { /* but we have not received a
629 * shutdown */
630 s->rwstate = SSL_NOTHING;
631 SSL3_RECORD_set_length(rr, 0);
632 SSL3_RECORD_set_read(rr);
633 return 0;
634 }
635
636 if (SSL3_RECORD_get_type(rr) == SSL3_RT_CHANGE_CIPHER_SPEC) {
637 /*
638 * We can't process a CCS now, because previous handshake messages
639 * are still missing, so just drop it.
640 */
641 SSL3_RECORD_set_length(rr, 0);
642 SSL3_RECORD_set_read(rr);
643 goto start;
644 }
645
646 /*
647 * Unexpected handshake message (Client Hello, or protocol violation)
648 */
649 if ((SSL3_RECORD_get_type(rr) == SSL3_RT_HANDSHAKE) &&
650 !ossl_statem_get_in_handshake(s)) {
651 struct hm_header_st msg_hdr;
652
653 /*
654 * This may just be a stale retransmit. Also sanity check that we have
655 * at least enough record bytes for a message header
656 */
657 if (SSL3_RECORD_get_epoch(rr) != s->rlayer.d->r_epoch
658 || SSL3_RECORD_get_length(rr) < DTLS1_HM_HEADER_LENGTH) {
659 SSL3_RECORD_set_length(rr, 0);
660 SSL3_RECORD_set_read(rr);
661 goto start;
662 }
663
664 dtls1_get_message_header(rr->data, &msg_hdr);
665
666 /*
667 * If we are server, we may have a repeated FINISHED of the client
668 * here, then retransmit our CCS and FINISHED.
669 */
670 if (msg_hdr.type == SSL3_MT_FINISHED) {
671 if (dtls1_check_timeout_num(s) < 0) {
672 /* SSLfatal) already called */
673 return -1;
674 }
675
676 if (dtls1_retransmit_buffered_messages(s) <= 0) {
677 /* Fail if we encountered a fatal error */
678 if (ossl_statem_in_error(s))
679 return -1;
680 }
681 SSL3_RECORD_set_length(rr, 0);
682 SSL3_RECORD_set_read(rr);
683 if (!(s->mode & SSL_MODE_AUTO_RETRY)) {
684 if (SSL3_BUFFER_get_left(&s->rlayer.rbuf) == 0) {
685 /* no read-ahead left? */
686 BIO *bio;
687
688 s->rwstate = SSL_READING;
689 bio = SSL_get_rbio(s);
690 BIO_clear_retry_flags(bio);
691 BIO_set_retry_read(bio);
692 return -1;
693 }
694 }
695 goto start;
696 }
697
698 /*
699 * To get here we must be trying to read app data but found handshake
700 * data. But if we're trying to read app data, and we're not in init
701 * (which is tested for at the top of this function) then init must be
702 * finished
703 */
704 if (!ossl_assert(SSL_is_init_finished(s))) {
705 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
706 return -1;
707 }
708
709 /* We found handshake data, so we're going back into init */
710 ossl_statem_set_in_init(s, 1);
711
712 i = s->handshake_func(s);
713 /* SSLfatal() called if appropriate */
714 if (i < 0)
715 return i;
716 if (i == 0)
717 return -1;
718
719 if (!(s->mode & SSL_MODE_AUTO_RETRY)) {
720 if (SSL3_BUFFER_get_left(&s->rlayer.rbuf) == 0) {
721 /* no read-ahead left? */
722 BIO *bio;
723 /*
724 * In the case where we try to read application data, but we
725 * trigger an SSL handshake, we return -1 with the retry
726 * option set. Otherwise renegotiation may cause nasty
727 * problems in the blocking world
728 */
729 s->rwstate = SSL_READING;
730 bio = SSL_get_rbio(s);
731 BIO_clear_retry_flags(bio);
732 BIO_set_retry_read(bio);
733 return -1;
734 }
735 }
736 goto start;
737 }
738
739 switch (SSL3_RECORD_get_type(rr)) {
740 default:
741 SSLfatal(s, SSL_AD_UNEXPECTED_MESSAGE, SSL_R_UNEXPECTED_RECORD);
742 return -1;
743 case SSL3_RT_CHANGE_CIPHER_SPEC:
744 case SSL3_RT_ALERT:
745 case SSL3_RT_HANDSHAKE:
746 /*
747 * we already handled all of these, with the possible exception of
748 * SSL3_RT_HANDSHAKE when ossl_statem_get_in_handshake(s) is true, but
749 * that should not happen when type != rr->type
750 */
751 SSLfatal(s, SSL_AD_UNEXPECTED_MESSAGE, ERR_R_INTERNAL_ERROR);
752 return -1;
753 case SSL3_RT_APPLICATION_DATA:
754 /*
755 * At this point, we were expecting handshake data, but have
756 * application data. If the library was running inside ssl3_read()
757 * (i.e. in_read_app_data is set) and it makes sense to read
758 * application data at this point (session renegotiation not yet
759 * started), we will indulge it.
760 */
761 if (s->s3.in_read_app_data &&
762 (s->s3.total_renegotiations != 0) &&
763 ossl_statem_app_data_allowed(s)) {
764 s->s3.in_read_app_data = 2;
765 return -1;
766 } else {
767 SSLfatal(s, SSL_AD_UNEXPECTED_MESSAGE, SSL_R_UNEXPECTED_RECORD);
768 return -1;
769 }
770 }
771 /* not reached */
772 }
773
774 /*
775 * Call this to write data in records of type 'type' It will return <= 0 if
776 * not all data has been sent or non-blocking IO.
777 */
dtls1_write_bytes(SSL * s,int type,const void * buf,size_t len,size_t * written)778 int dtls1_write_bytes(SSL *s, int type, const void *buf, size_t len,
779 size_t *written)
780 {
781 int i;
782
783 if (!ossl_assert(len <= SSL3_RT_MAX_PLAIN_LENGTH)) {
784 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
785 return -1;
786 }
787 s->rwstate = SSL_NOTHING;
788 i = do_dtls1_write(s, type, buf, len, 0, written);
789 return i;
790 }
791
do_dtls1_write(SSL * s,int type,const unsigned char * buf,size_t len,int create_empty_fragment,size_t * written)792 int do_dtls1_write(SSL *s, int type, const unsigned char *buf,
793 size_t len, int create_empty_fragment, size_t *written)
794 {
795 unsigned char *p, *pseq;
796 int i, mac_size, clear = 0;
797 size_t prefix_len = 0;
798 int eivlen;
799 SSL3_RECORD wr;
800 SSL3_BUFFER *wb;
801 SSL_SESSION *sess;
802
803 wb = &s->rlayer.wbuf[0];
804
805 /*
806 * DTLS writes whole datagrams, so there can't be anything left in
807 * the buffer.
808 */
809 if (!ossl_assert(SSL3_BUFFER_get_left(wb) == 0)) {
810 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
811 return 0;
812 }
813
814 /* If we have an alert to send, lets send it */
815 if (s->s3.alert_dispatch) {
816 i = s->method->ssl_dispatch_alert(s);
817 if (i <= 0)
818 return i;
819 /* if it went, fall through and send more stuff */
820 }
821
822 if (len == 0 && !create_empty_fragment)
823 return 0;
824
825 if (len > ssl_get_max_send_fragment(s)) {
826 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_EXCEEDS_MAX_FRAGMENT_SIZE);
827 return 0;
828 }
829
830 sess = s->session;
831
832 if ((sess == NULL)
833 || (s->enc_write_ctx == NULL)
834 || (EVP_MD_CTX_get0_md(s->write_hash) == NULL))
835 clear = 1;
836
837 if (clear)
838 mac_size = 0;
839 else {
840 mac_size = EVP_MD_CTX_get_size(s->write_hash);
841 if (mac_size < 0) {
842 SSLfatal(s, SSL_AD_INTERNAL_ERROR,
843 SSL_R_EXCEEDS_MAX_FRAGMENT_SIZE);
844 return -1;
845 }
846 }
847
848 p = SSL3_BUFFER_get_buf(wb) + prefix_len;
849
850 /* write the header */
851
852 *(p++) = type & 0xff;
853 SSL3_RECORD_set_type(&wr, type);
854 /*
855 * Special case: for hello verify request, client version 1.0 and we
856 * haven't decided which version to use yet send back using version 1.0
857 * header: otherwise some clients will ignore it.
858 */
859 if (s->method->version == DTLS_ANY_VERSION &&
860 s->max_proto_version != DTLS1_BAD_VER) {
861 *(p++) = DTLS1_VERSION >> 8;
862 *(p++) = DTLS1_VERSION & 0xff;
863 } else {
864 *(p++) = s->version >> 8;
865 *(p++) = s->version & 0xff;
866 }
867
868 /* field where we are to write out packet epoch, seq num and len */
869 pseq = p;
870 p += 10;
871
872 /* Explicit IV length, block ciphers appropriate version flag */
873 if (s->enc_write_ctx) {
874 int mode = EVP_CIPHER_CTX_get_mode(s->enc_write_ctx);
875 if (mode == EVP_CIPH_CBC_MODE) {
876 eivlen = EVP_CIPHER_CTX_get_iv_length(s->enc_write_ctx);
877 if (eivlen < 0) {
878 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_LIBRARY_BUG);
879 return -1;
880 }
881 if (eivlen <= 1)
882 eivlen = 0;
883 }
884 /* Need explicit part of IV for GCM mode */
885 else if (mode == EVP_CIPH_GCM_MODE)
886 eivlen = EVP_GCM_TLS_EXPLICIT_IV_LEN;
887 else if (mode == EVP_CIPH_CCM_MODE)
888 eivlen = EVP_CCM_TLS_EXPLICIT_IV_LEN;
889 else
890 eivlen = 0;
891 } else
892 eivlen = 0;
893
894 /* lets setup the record stuff. */
895 SSL3_RECORD_set_data(&wr, p + eivlen); /* make room for IV in case of CBC */
896 SSL3_RECORD_set_length(&wr, len);
897 SSL3_RECORD_set_input(&wr, (unsigned char *)buf);
898
899 /*
900 * we now 'read' from wr.input, wr.length bytes into wr.data
901 */
902
903 /* first we compress */
904 if (s->compress != NULL) {
905 if (!ssl3_do_compress(s, &wr)) {
906 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_COMPRESSION_FAILURE);
907 return -1;
908 }
909 } else {
910 memcpy(SSL3_RECORD_get_data(&wr), SSL3_RECORD_get_input(&wr),
911 SSL3_RECORD_get_length(&wr));
912 SSL3_RECORD_reset_input(&wr);
913 }
914
915 /*
916 * we should still have the output to wr.data and the input from
917 * wr.input. Length should be wr.length. wr.data still points in the
918 * wb->buf
919 */
920
921 if (!SSL_WRITE_ETM(s) && mac_size != 0) {
922 if (!s->method->ssl3_enc->mac(s, &wr,
923 &(p[SSL3_RECORD_get_length(&wr) + eivlen]),
924 1)) {
925 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
926 return -1;
927 }
928 SSL3_RECORD_add_length(&wr, mac_size);
929 }
930
931 /* this is true regardless of mac size */
932 SSL3_RECORD_set_data(&wr, p);
933 SSL3_RECORD_reset_input(&wr);
934
935 if (eivlen)
936 SSL3_RECORD_add_length(&wr, eivlen);
937
938 if (s->method->ssl3_enc->enc(s, &wr, 1, 1, NULL, mac_size) < 1) {
939 if (!ossl_statem_in_error(s)) {
940 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
941 }
942 return -1;
943 }
944
945 if (SSL_WRITE_ETM(s) && mac_size != 0) {
946 if (!s->method->ssl3_enc->mac(s, &wr,
947 &(p[SSL3_RECORD_get_length(&wr)]), 1)) {
948 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
949 return -1;
950 }
951 SSL3_RECORD_add_length(&wr, mac_size);
952 }
953
954 /* record length after mac and block padding */
955
956 /* there's only one epoch between handshake and app data */
957
958 s2n(s->rlayer.d->w_epoch, pseq);
959
960 memcpy(pseq, &(s->rlayer.write_sequence[2]), 6);
961 pseq += 6;
962 s2n(SSL3_RECORD_get_length(&wr), pseq);
963
964 if (s->msg_callback)
965 s->msg_callback(1, 0, SSL3_RT_HEADER, pseq - DTLS1_RT_HEADER_LENGTH,
966 DTLS1_RT_HEADER_LENGTH, s, s->msg_callback_arg);
967
968 /*
969 * we should now have wr.data pointing to the encrypted data, which is
970 * wr->length long
971 */
972 SSL3_RECORD_set_type(&wr, type); /* not needed but helps for debugging */
973 SSL3_RECORD_add_length(&wr, DTLS1_RT_HEADER_LENGTH);
974
975 ssl3_record_sequence_update(&(s->rlayer.write_sequence[0]));
976
977 if (create_empty_fragment) {
978 /*
979 * we are in a recursive call; just return the length, don't write
980 * out anything here
981 */
982 *written = wr.length;
983 return 1;
984 }
985
986 /* now let's set up wb */
987 SSL3_BUFFER_set_left(wb, prefix_len + SSL3_RECORD_get_length(&wr));
988 SSL3_BUFFER_set_offset(wb, 0);
989
990 /*
991 * memorize arguments so that ssl3_write_pending can detect bad write
992 * retries later
993 */
994 s->rlayer.wpend_tot = len;
995 s->rlayer.wpend_buf = buf;
996 s->rlayer.wpend_type = type;
997 s->rlayer.wpend_ret = len;
998
999 /* we now just need to write the buffer. Calls SSLfatal() as required. */
1000 return ssl3_write_pending(s, type, buf, len, written);
1001 }
1002
dtls1_get_bitmap(SSL * s,SSL3_RECORD * rr,unsigned int * is_next_epoch)1003 DTLS1_BITMAP *dtls1_get_bitmap(SSL *s, SSL3_RECORD *rr,
1004 unsigned int *is_next_epoch)
1005 {
1006
1007 *is_next_epoch = 0;
1008
1009 /* In current epoch, accept HM, CCS, DATA, & ALERT */
1010 if (rr->epoch == s->rlayer.d->r_epoch)
1011 return &s->rlayer.d->bitmap;
1012
1013 /*
1014 * Only HM and ALERT messages can be from the next epoch and only if we
1015 * have already processed all of the unprocessed records from the last
1016 * epoch
1017 */
1018 else if (rr->epoch == (unsigned long)(s->rlayer.d->r_epoch + 1) &&
1019 s->rlayer.d->unprocessed_rcds.epoch != s->rlayer.d->r_epoch &&
1020 (rr->type == SSL3_RT_HANDSHAKE || rr->type == SSL3_RT_ALERT)) {
1021 *is_next_epoch = 1;
1022 return &s->rlayer.d->next_bitmap;
1023 }
1024
1025 return NULL;
1026 }
1027
dtls1_reset_seq_numbers(SSL * s,int rw)1028 void dtls1_reset_seq_numbers(SSL *s, int rw)
1029 {
1030 unsigned char *seq;
1031 unsigned int seq_bytes = sizeof(s->rlayer.read_sequence);
1032
1033 if (rw & SSL3_CC_READ) {
1034 seq = s->rlayer.read_sequence;
1035 s->rlayer.d->r_epoch++;
1036 memcpy(&s->rlayer.d->bitmap, &s->rlayer.d->next_bitmap,
1037 sizeof(s->rlayer.d->bitmap));
1038 memset(&s->rlayer.d->next_bitmap, 0, sizeof(s->rlayer.d->next_bitmap));
1039
1040 /*
1041 * We must not use any buffered messages received from the previous
1042 * epoch
1043 */
1044 dtls1_clear_received_buffer(s);
1045 } else {
1046 seq = s->rlayer.write_sequence;
1047 memcpy(s->rlayer.d->last_write_sequence, seq,
1048 sizeof(s->rlayer.write_sequence));
1049 s->rlayer.d->w_epoch++;
1050 }
1051
1052 memset(seq, 0, seq_bytes);
1053 }
1054