2 * Copyright 2015-2021 The OpenSSL Project Authors. All Rights Reserved.
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
10 #if defined(__TANDEM) && defined(_SPT_MODEL_)
11 # include <spthread.h>
12 # include <spt_extensions.h> /* timeval */
15 #include "internal/cryptlib.h"
16 #include <openssl/rand.h>
17 #include "../ssl_local.h"
18 #include "statem_local.h"
22 * This file implements the SSL/TLS/DTLS state machines.
24 * There are two primary state machines:
26 * 1) Message flow state machine
27 * 2) Handshake state machine
29 * The Message flow state machine controls the reading and sending of messages
30 * including handling of non-blocking IO events, flushing of the underlying
31 * write BIO, handling unexpected messages, etc. It is itself broken into two
32 * separate sub-state machines which control reading and writing respectively.
34 * The Handshake state machine keeps track of the current SSL/TLS handshake
35 * state. Transitions of the handshake state are the result of events that
36 * occur within the Message flow state machine.
38 * Overall it looks like this:
40 * --------------------------------------------- -------------------
42 * | Message flow state machine | | |
44 * | -------------------- -------------------- | Transition | Handshake state |
45 * | | MSG_FLOW_READING | | MSG_FLOW_WRITING | | Event | machine |
46 * | | sub-state | | sub-state | |----------->| |
47 * | | machine for | | machine for | | | |
48 * | | reading messages | | writing messages | | | |
49 * | -------------------- -------------------- | | |
51 * --------------------------------------------- -------------------
55 /* Sub state machine return values */
57 /* Something bad happened or NBIO */
59 /* Sub state finished go to the next sub state */
61 /* Sub state finished and handshake was completed */
62 SUB_STATE_END_HANDSHAKE
65 static int state_machine(SSL *s, int server);
66 static void init_read_state_machine(SSL *s);
67 static SUB_STATE_RETURN read_state_machine(SSL *s);
68 static void init_write_state_machine(SSL *s);
69 static SUB_STATE_RETURN write_state_machine(SSL *s);
71 OSSL_HANDSHAKE_STATE SSL_get_state(const SSL *ssl)
73 return ssl->statem.hand_state;
76 int SSL_in_init(const SSL *s)
78 return s->statem.in_init;
81 int SSL_is_init_finished(const SSL *s)
83 return !(s->statem.in_init) && (s->statem.hand_state == TLS_ST_OK);
86 int SSL_in_before(const SSL *s)
89 * Historically being "in before" meant before anything had happened. In the
90 * current code though we remain in the "before" state for a while after we
91 * have started the handshake process (e.g. as a server waiting for the
92 * first message to arrive). There "in before" is taken to mean "in before"
93 * and not started any handshake process yet.
95 return (s->statem.hand_state == TLS_ST_BEFORE)
96 && (s->statem.state == MSG_FLOW_UNINITED);
100 * Clear the state machine state and reset back to MSG_FLOW_UNINITED
102 void ossl_statem_clear(SSL *s)
104 s->statem.state = MSG_FLOW_UNINITED;
105 s->statem.hand_state = TLS_ST_BEFORE;
106 s->statem.in_init = 1;
107 s->statem.no_cert_verify = 0;
111 * Set the state machine up ready for a renegotiation handshake
113 void ossl_statem_set_renegotiate(SSL *s)
115 s->statem.in_init = 1;
116 s->statem.request_state = TLS_ST_SW_HELLO_REQ;
119 void ossl_statem_send_fatal(SSL *s, int al)
121 /* We shouldn't call SSLfatal() twice. Once is enough */
122 if (s->statem.in_init && s->statem.state == MSG_FLOW_ERROR)
124 s->statem.in_init = 1;
125 s->statem.state = MSG_FLOW_ERROR;
126 if (al != SSL_AD_NO_ALERT
127 && s->statem.enc_write_state != ENC_WRITE_STATE_INVALID)
128 ssl3_send_alert(s, SSL3_AL_FATAL, al);
132 * Error reporting building block that's used instead of ERR_set_error().
133 * In addition to what ERR_set_error() does, this puts the state machine
134 * into an error state and sends an alert if appropriate.
135 * This is a permanent error for the current connection.
137 void ossl_statem_fatal(SSL *s, int al, int reason, const char *fmt, ...)
142 ERR_vset_error(ERR_LIB_SSL, reason, fmt, args);
145 ossl_statem_send_fatal(s, al);
149 * This macro should only be called if we are already expecting to be in
150 * a fatal error state. We verify that we are, and set it if not (this would
153 #define check_fatal(s) \
155 if (!ossl_assert((s)->statem.in_init \
156 && (s)->statem.state == MSG_FLOW_ERROR)) \
157 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_MISSING_FATAL); \
161 * Discover whether the current connection is in the error state.
163 * Valid return values are:
167 int ossl_statem_in_error(const SSL *s)
169 if (s->statem.state == MSG_FLOW_ERROR)
175 void ossl_statem_set_in_init(SSL *s, int init)
177 s->statem.in_init = init;
180 int ossl_statem_get_in_handshake(SSL *s)
182 return s->statem.in_handshake;
185 void ossl_statem_set_in_handshake(SSL *s, int inhand)
188 s->statem.in_handshake++;
190 s->statem.in_handshake--;
193 /* Are we in a sensible state to skip over unreadable early data? */
194 int ossl_statem_skip_early_data(SSL *s)
196 if (s->ext.early_data != SSL_EARLY_DATA_REJECTED)
200 || s->statem.hand_state != TLS_ST_EARLY_DATA
201 || s->hello_retry_request == SSL_HRR_COMPLETE)
208 * Called when we are in SSL_read*(), SSL_write*(), or SSL_accept()
209 * /SSL_connect()/SSL_do_handshake(). Used to test whether we are in an early
210 * data state and whether we should attempt to move the handshake on if so.
211 * |sending| is 1 if we are attempting to send data (SSL_write*()), 0 if we are
212 * attempting to read data (SSL_read*()), or -1 if we are in SSL_do_handshake()
215 void ossl_statem_check_finish_init(SSL *s, int sending)
218 if (s->statem.hand_state == TLS_ST_PENDING_EARLY_DATA_END
219 || s->statem.hand_state == TLS_ST_EARLY_DATA) {
220 ossl_statem_set_in_init(s, 1);
221 if (s->early_data_state == SSL_EARLY_DATA_WRITE_RETRY) {
223 * SSL_connect() or SSL_do_handshake() has been called directly.
224 * We don't allow any more writing of early data.
226 s->early_data_state = SSL_EARLY_DATA_FINISHED_WRITING;
229 } else if (!s->server) {
230 if ((sending && (s->statem.hand_state == TLS_ST_PENDING_EARLY_DATA_END
231 || s->statem.hand_state == TLS_ST_EARLY_DATA)
232 && s->early_data_state != SSL_EARLY_DATA_WRITING)
233 || (!sending && s->statem.hand_state == TLS_ST_EARLY_DATA)) {
234 ossl_statem_set_in_init(s, 1);
236 * SSL_write() has been called directly. We don't allow any more
237 * writing of early data.
239 if (sending && s->early_data_state == SSL_EARLY_DATA_WRITE_RETRY)
240 s->early_data_state = SSL_EARLY_DATA_FINISHED_WRITING;
243 if (s->early_data_state == SSL_EARLY_DATA_FINISHED_READING
244 && s->statem.hand_state == TLS_ST_EARLY_DATA)
245 ossl_statem_set_in_init(s, 1);
249 void ossl_statem_set_hello_verify_done(SSL *s)
251 s->statem.state = MSG_FLOW_UNINITED;
252 s->statem.in_init = 1;
254 * This will get reset (briefly) back to TLS_ST_BEFORE when we enter
255 * state_machine() because |state| is MSG_FLOW_UNINITED, but until then any
256 * calls to SSL_in_before() will return false. Also calls to
257 * SSL_state_string() and SSL_state_string_long() will return something
260 s->statem.hand_state = TLS_ST_SR_CLNT_HELLO;
263 int ossl_statem_connect(SSL *s)
265 return state_machine(s, 0);
268 int ossl_statem_accept(SSL *s)
270 return state_machine(s, 1);
273 typedef void (*info_cb) (const SSL *, int, int);
275 static info_cb get_callback(SSL *s)
277 if (s->info_callback != NULL)
278 return s->info_callback;
279 else if (s->ctx->info_callback != NULL)
280 return s->ctx->info_callback;
286 * The main message flow state machine. We start in the MSG_FLOW_UNINITED or
287 * MSG_FLOW_FINISHED state and finish in MSG_FLOW_FINISHED. Valid states and
288 * transitions are as follows:
290 * MSG_FLOW_UNINITED MSG_FLOW_FINISHED
292 * +-----------------------+
294 * MSG_FLOW_WRITING <---> MSG_FLOW_READING
302 * We may exit at any point due to an error or NBIO event. If an NBIO event
303 * occurs then we restart at the point we left off when we are recalled.
304 * MSG_FLOW_WRITING and MSG_FLOW_READING have sub-state machines associated with them.
306 * In addition to the above there is also the MSG_FLOW_ERROR state. We can move
307 * into that state at any point in the event that an irrecoverable error occurs.
309 * Valid return values are:
313 static int state_machine(SSL *s, int server)
316 void (*cb) (const SSL *ssl, int type, int val) = NULL;
317 OSSL_STATEM *st = &s->statem;
321 if (st->state == MSG_FLOW_ERROR) {
322 /* Shouldn't have been called if we're already in the error state */
329 cb = get_callback(s);
332 if (!SSL_in_init(s) || SSL_in_before(s)) {
334 * If we are stateless then we already called SSL_clear() - don't do
335 * it again and clear the STATELESS flag itself.
337 if ((s->s3.flags & TLS1_FLAGS_STATELESS) == 0 && !SSL_clear(s))
340 #ifndef OPENSSL_NO_SCTP
341 if (SSL_IS_DTLS(s) && BIO_dgram_is_sctp(SSL_get_wbio(s))) {
343 * Notify SCTP BIO socket to enter handshake mode and prevent stream
344 * identifier other than 0.
346 BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_SET_IN_HANDSHAKE,
347 st->in_handshake, NULL);
351 /* Initialise state machine */
352 if (st->state == MSG_FLOW_UNINITED
353 || st->state == MSG_FLOW_FINISHED) {
354 if (st->state == MSG_FLOW_UNINITED) {
355 st->hand_state = TLS_ST_BEFORE;
356 st->request_state = TLS_ST_BEFORE;
361 if (SSL_IS_FIRST_HANDSHAKE(s) || !SSL_IS_TLS13(s))
362 cb(s, SSL_CB_HANDSHAKE_START, 1);
366 * Fatal errors in this block don't send an alert because we have
367 * failed to even initialise properly. Sending an alert is probably
371 if (SSL_IS_DTLS(s)) {
372 if ((s->version & 0xff00) != (DTLS1_VERSION & 0xff00) &&
373 (server || (s->version & 0xff00) != (DTLS1_BAD_VER & 0xff00))) {
374 SSLfatal(s, SSL_AD_NO_ALERT, ERR_R_INTERNAL_ERROR);
378 if ((s->version >> 8) != SSL3_VERSION_MAJOR) {
379 SSLfatal(s, SSL_AD_NO_ALERT, ERR_R_INTERNAL_ERROR);
384 if (!ssl_security(s, SSL_SECOP_VERSION, 0, s->version, NULL)) {
385 SSLfatal(s, SSL_AD_NO_ALERT, ERR_R_INTERNAL_ERROR);
389 if (s->init_buf == NULL) {
390 if ((buf = BUF_MEM_new()) == NULL) {
391 SSLfatal(s, SSL_AD_NO_ALERT, ERR_R_INTERNAL_ERROR);
394 if (!BUF_MEM_grow(buf, SSL3_RT_MAX_PLAIN_LENGTH)) {
395 SSLfatal(s, SSL_AD_NO_ALERT, ERR_R_INTERNAL_ERROR);
402 if (!ssl3_setup_buffers(s)) {
403 SSLfatal(s, SSL_AD_NO_ALERT, ERR_R_INTERNAL_ERROR);
409 * Should have been reset by tls_process_finished, too.
411 s->s3.change_cipher_spec = 0;
414 * Ok, we now need to push on a buffering BIO ...but not with
417 #ifndef OPENSSL_NO_SCTP
418 if (!SSL_IS_DTLS(s) || !BIO_dgram_is_sctp(SSL_get_wbio(s)))
420 if (!ssl_init_wbio_buffer(s)) {
421 SSLfatal(s, SSL_AD_NO_ALERT, ERR_R_INTERNAL_ERROR);
425 if ((SSL_in_before(s))
427 if (!tls_setup_handshake(s)) {
428 /* SSLfatal() already called */
432 if (SSL_IS_FIRST_HANDSHAKE(s))
433 st->read_state_first_init = 1;
436 st->state = MSG_FLOW_WRITING;
437 init_write_state_machine(s);
440 while (st->state != MSG_FLOW_FINISHED) {
441 if (st->state == MSG_FLOW_READING) {
442 ssret = read_state_machine(s);
443 if (ssret == SUB_STATE_FINISHED) {
444 st->state = MSG_FLOW_WRITING;
445 init_write_state_machine(s);
450 } else if (st->state == MSG_FLOW_WRITING) {
451 ssret = write_state_machine(s);
452 if (ssret == SUB_STATE_FINISHED) {
453 st->state = MSG_FLOW_READING;
454 init_read_state_machine(s);
455 } else if (ssret == SUB_STATE_END_HANDSHAKE) {
456 st->state = MSG_FLOW_FINISHED;
464 ERR_raise(ERR_LIB_SSL, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
474 #ifndef OPENSSL_NO_SCTP
475 if (SSL_IS_DTLS(s) && BIO_dgram_is_sctp(SSL_get_wbio(s))) {
477 * Notify SCTP BIO socket to leave handshake mode and allow stream
478 * identifier other than 0.
480 BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_SET_IN_HANDSHAKE,
481 st->in_handshake, NULL);
488 cb(s, SSL_CB_ACCEPT_EXIT, ret);
490 cb(s, SSL_CB_CONNECT_EXIT, ret);
496 * Initialise the MSG_FLOW_READING sub-state machine
498 static void init_read_state_machine(SSL *s)
500 OSSL_STATEM *st = &s->statem;
502 st->read_state = READ_STATE_HEADER;
505 static int grow_init_buf(SSL *s, size_t size) {
507 size_t msg_offset = (char *)s->init_msg - s->init_buf->data;
509 if (!BUF_MEM_grow_clean(s->init_buf, (int)size))
512 if (size < msg_offset)
515 s->init_msg = s->init_buf->data + msg_offset;
521 * This function implements the sub-state machine when the message flow is in
522 * MSG_FLOW_READING. The valid sub-states and transitions are:
524 * READ_STATE_HEADER <--+<-------------+
527 * READ_STATE_BODY -----+-->READ_STATE_POST_PROCESS
529 * +----------------------------+
531 * [SUB_STATE_FINISHED]
533 * READ_STATE_HEADER has the responsibility for reading in the message header
534 * and transitioning the state of the handshake state machine.
536 * READ_STATE_BODY reads in the rest of the message and then subsequently
539 * READ_STATE_POST_PROCESS is an optional step that may occur if some post
540 * processing activity performed on the message may block.
542 * Any of the above states could result in an NBIO event occurring in which case
543 * control returns to the calling application. When this function is recalled we
544 * will resume in the same state where we left off.
546 static SUB_STATE_RETURN read_state_machine(SSL *s)
548 OSSL_STATEM *st = &s->statem;
551 int (*transition) (SSL *s, int mt);
553 MSG_PROCESS_RETURN(*process_message) (SSL *s, PACKET *pkt);
554 WORK_STATE(*post_process_message) (SSL *s, WORK_STATE wst);
555 size_t (*max_message_size) (SSL *s);
556 void (*cb) (const SSL *ssl, int type, int val) = NULL;
558 cb = get_callback(s);
561 transition = ossl_statem_server_read_transition;
562 process_message = ossl_statem_server_process_message;
563 max_message_size = ossl_statem_server_max_message_size;
564 post_process_message = ossl_statem_server_post_process_message;
566 transition = ossl_statem_client_read_transition;
567 process_message = ossl_statem_client_process_message;
568 max_message_size = ossl_statem_client_max_message_size;
569 post_process_message = ossl_statem_client_post_process_message;
572 if (st->read_state_first_init) {
574 st->read_state_first_init = 0;
578 switch (st->read_state) {
579 case READ_STATE_HEADER:
580 /* Get the state the peer wants to move to */
581 if (SSL_IS_DTLS(s)) {
583 * In DTLS we get the whole message in one go - header and body
585 ret = dtls_get_message(s, &mt);
587 ret = tls_get_message_header(s, &mt);
591 /* Could be non-blocking IO */
592 return SUB_STATE_ERROR;
596 /* Notify callback of an impending state change */
598 cb(s, SSL_CB_ACCEPT_LOOP, 1);
600 cb(s, SSL_CB_CONNECT_LOOP, 1);
603 * Validate that we are allowed to move to the new state and move
604 * to that state if so
606 if (!transition(s, mt))
607 return SUB_STATE_ERROR;
609 if (s->s3.tmp.message_size > max_message_size(s)) {
610 SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER,
611 SSL_R_EXCESSIVE_MESSAGE_SIZE);
612 return SUB_STATE_ERROR;
615 /* dtls_get_message already did this */
617 && s->s3.tmp.message_size > 0
618 && !grow_init_buf(s, s->s3.tmp.message_size
619 + SSL3_HM_HEADER_LENGTH)) {
620 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_BUF_LIB);
621 return SUB_STATE_ERROR;
624 st->read_state = READ_STATE_BODY;
627 case READ_STATE_BODY:
628 if (SSL_IS_DTLS(s)) {
630 * Actually we already have the body, but we give DTLS the
631 * opportunity to do any further processing.
633 ret = dtls_get_message_body(s, &len);
635 ret = tls_get_message_body(s, &len);
638 /* Could be non-blocking IO */
639 return SUB_STATE_ERROR;
643 if (!PACKET_buf_init(&pkt, s->init_msg, len)) {
644 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
645 return SUB_STATE_ERROR;
647 ret = process_message(s, &pkt);
649 /* Discard the packet data */
653 case MSG_PROCESS_ERROR:
655 return SUB_STATE_ERROR;
657 case MSG_PROCESS_FINISHED_READING:
658 if (SSL_IS_DTLS(s)) {
661 return SUB_STATE_FINISHED;
663 case MSG_PROCESS_CONTINUE_PROCESSING:
664 st->read_state = READ_STATE_POST_PROCESS;
665 st->read_state_work = WORK_MORE_A;
669 st->read_state = READ_STATE_HEADER;
674 case READ_STATE_POST_PROCESS:
675 st->read_state_work = post_process_message(s, st->read_state_work);
676 switch (st->read_state_work) {
683 return SUB_STATE_ERROR;
685 case WORK_FINISHED_CONTINUE:
686 st->read_state = READ_STATE_HEADER;
689 case WORK_FINISHED_STOP:
690 if (SSL_IS_DTLS(s)) {
693 return SUB_STATE_FINISHED;
698 /* Shouldn't happen */
699 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
700 return SUB_STATE_ERROR;
706 * Send a previously constructed message to the peer.
708 static int statem_do_write(SSL *s)
710 OSSL_STATEM *st = &s->statem;
712 if (st->hand_state == TLS_ST_CW_CHANGE
713 || st->hand_state == TLS_ST_SW_CHANGE) {
715 return dtls1_do_write(s, SSL3_RT_CHANGE_CIPHER_SPEC);
717 return ssl3_do_write(s, SSL3_RT_CHANGE_CIPHER_SPEC);
719 return ssl_do_write(s);
724 * Initialise the MSG_FLOW_WRITING sub-state machine
726 static void init_write_state_machine(SSL *s)
728 OSSL_STATEM *st = &s->statem;
730 st->write_state = WRITE_STATE_TRANSITION;
734 * This function implements the sub-state machine when the message flow is in
735 * MSG_FLOW_WRITING. The valid sub-states and transitions are:
737 * +-> WRITE_STATE_TRANSITION ------> [SUB_STATE_FINISHED]
740 * | WRITE_STATE_PRE_WORK -----> [SUB_STATE_END_HANDSHAKE]
746 * | WRITE_STATE_POST_WORK
750 * WRITE_STATE_TRANSITION transitions the state of the handshake state machine
752 * WRITE_STATE_PRE_WORK performs any work necessary to prepare the later
753 * sending of the message. This could result in an NBIO event occurring in
754 * which case control returns to the calling application. When this function
755 * is recalled we will resume in the same state where we left off.
757 * WRITE_STATE_SEND sends the message and performs any work to be done after
760 * WRITE_STATE_POST_WORK performs any work necessary after the sending of the
761 * message has been completed. As for WRITE_STATE_PRE_WORK this could also
762 * result in an NBIO event.
764 static SUB_STATE_RETURN write_state_machine(SSL *s)
766 OSSL_STATEM *st = &s->statem;
768 WRITE_TRAN(*transition) (SSL *s);
769 WORK_STATE(*pre_work) (SSL *s, WORK_STATE wst);
770 WORK_STATE(*post_work) (SSL *s, WORK_STATE wst);
771 int (*get_construct_message_f) (SSL *s,
772 int (**confunc) (SSL *s, WPACKET *pkt),
774 void (*cb) (const SSL *ssl, int type, int val) = NULL;
775 int (*confunc) (SSL *s, WPACKET *pkt);
779 cb = get_callback(s);
782 transition = ossl_statem_server_write_transition;
783 pre_work = ossl_statem_server_pre_work;
784 post_work = ossl_statem_server_post_work;
785 get_construct_message_f = ossl_statem_server_construct_message;
787 transition = ossl_statem_client_write_transition;
788 pre_work = ossl_statem_client_pre_work;
789 post_work = ossl_statem_client_post_work;
790 get_construct_message_f = ossl_statem_client_construct_message;
794 switch (st->write_state) {
795 case WRITE_STATE_TRANSITION:
797 /* Notify callback of an impending state change */
799 cb(s, SSL_CB_ACCEPT_LOOP, 1);
801 cb(s, SSL_CB_CONNECT_LOOP, 1);
803 switch (transition(s)) {
804 case WRITE_TRAN_CONTINUE:
805 st->write_state = WRITE_STATE_PRE_WORK;
806 st->write_state_work = WORK_MORE_A;
809 case WRITE_TRAN_FINISHED:
810 return SUB_STATE_FINISHED;
813 case WRITE_TRAN_ERROR:
815 return SUB_STATE_ERROR;
819 case WRITE_STATE_PRE_WORK:
820 switch (st->write_state_work = pre_work(s, st->write_state_work)) {
827 return SUB_STATE_ERROR;
829 case WORK_FINISHED_CONTINUE:
830 st->write_state = WRITE_STATE_SEND;
833 case WORK_FINISHED_STOP:
834 return SUB_STATE_END_HANDSHAKE;
836 if (!get_construct_message_f(s, &confunc, &mt)) {
837 /* SSLfatal() already called */
838 return SUB_STATE_ERROR;
840 if (mt == SSL3_MT_DUMMY) {
841 /* Skip construction and sending. This isn't a "real" state */
842 st->write_state = WRITE_STATE_POST_WORK;
843 st->write_state_work = WORK_MORE_A;
846 if (!WPACKET_init(&pkt, s->init_buf)
847 || !ssl_set_handshake_header(s, &pkt, mt)) {
848 WPACKET_cleanup(&pkt);
849 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
850 return SUB_STATE_ERROR;
852 if (confunc != NULL && !confunc(s, &pkt)) {
853 WPACKET_cleanup(&pkt);
855 return SUB_STATE_ERROR;
857 if (!ssl_close_construct_packet(s, &pkt, mt)
858 || !WPACKET_finish(&pkt)) {
859 WPACKET_cleanup(&pkt);
860 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
861 return SUB_STATE_ERROR;
866 case WRITE_STATE_SEND:
867 if (SSL_IS_DTLS(s) && st->use_timer) {
868 dtls1_start_timer(s);
870 ret = statem_do_write(s);
872 return SUB_STATE_ERROR;
874 st->write_state = WRITE_STATE_POST_WORK;
875 st->write_state_work = WORK_MORE_A;
878 case WRITE_STATE_POST_WORK:
879 switch (st->write_state_work = post_work(s, st->write_state_work)) {
886 return SUB_STATE_ERROR;
888 case WORK_FINISHED_CONTINUE:
889 st->write_state = WRITE_STATE_TRANSITION;
892 case WORK_FINISHED_STOP:
893 return SUB_STATE_END_HANDSHAKE;
898 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
899 return SUB_STATE_ERROR;
905 * Flush the write BIO
907 int statem_flush(SSL *s)
909 s->rwstate = SSL_WRITING;
910 if (BIO_flush(s->wbio) <= 0) {
913 s->rwstate = SSL_NOTHING;
919 * Called by the record layer to determine whether application data is
920 * allowed to be received in the current handshake state or not.
923 * 1: Yes (application data allowed)
924 * 0: No (application data not allowed)
926 int ossl_statem_app_data_allowed(SSL *s)
928 OSSL_STATEM *st = &s->statem;
930 if (st->state == MSG_FLOW_UNINITED)
933 if (!s->s3.in_read_app_data || (s->s3.total_renegotiations == 0))
938 * If we're a server and we haven't got as far as writing our
939 * ServerHello yet then we allow app data
941 if (st->hand_state == TLS_ST_BEFORE
942 || st->hand_state == TLS_ST_SR_CLNT_HELLO)
946 * If we're a client and we haven't read the ServerHello yet then we
949 if (st->hand_state == TLS_ST_CW_CLNT_HELLO)
957 * This function returns 1 if TLS exporter is ready to export keying
958 * material, or 0 if otherwise.
960 int ossl_statem_export_allowed(SSL *s)
962 return s->s3.previous_server_finished_len != 0
963 && s->statem.hand_state != TLS_ST_SW_FINISHED;
967 * Return 1 if early TLS exporter is ready to export keying material,
970 int ossl_statem_export_early_allowed(SSL *s)
973 * The early exporter secret is only present on the server if we
974 * have accepted early_data. It is present on the client as long
975 * as we have sent early_data.
977 return s->ext.early_data == SSL_EARLY_DATA_ACCEPTED
978 || (!s->server && s->ext.early_data != SSL_EARLY_DATA_NOT_SENT);