2 * Copyright 2015-2018 The OpenSSL Project Authors. All Rights Reserved.
4 * Licensed under the OpenSSL license (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 #include "internal/cryptlib.h"
11 #include <openssl/rand.h>
12 #include "../ssl_locl.h"
13 #include "statem_locl.h"
17 * This file implements the SSL/TLS/DTLS state machines.
19 * There are two primary state machines:
21 * 1) Message flow state machine
22 * 2) Handshake state machine
24 * The Message flow state machine controls the reading and sending of messages
25 * including handling of non-blocking IO events, flushing of the underlying
26 * write BIO, handling unexpected messages, etc. It is itself broken into two
27 * separate sub-state machines which control reading and writing respectively.
29 * The Handshake state machine keeps track of the current SSL/TLS handshake
30 * state. Transitions of the handshake state are the result of events that
31 * occur within the Message flow state machine.
33 * Overall it looks like this:
35 * --------------------------------------------- -------------------
37 * | Message flow state machine | | |
39 * | -------------------- -------------------- | Transition | Handshake state |
40 * | | MSG_FLOW_READING | | MSG_FLOW_WRITING | | Event | machine |
41 * | | sub-state | | sub-state | |----------->| |
42 * | | machine for | | machine for | | | |
43 * | | reading messages | | writing messages | | | |
44 * | -------------------- -------------------- | | |
46 * --------------------------------------------- -------------------
50 /* Sub state machine return values */
52 /* Something bad happened or NBIO */
54 /* Sub state finished go to the next sub state */
56 /* Sub state finished and handshake was completed */
57 SUB_STATE_END_HANDSHAKE
60 static int state_machine(SSL *s, int server);
61 static void init_read_state_machine(SSL *s);
62 static SUB_STATE_RETURN read_state_machine(SSL *s);
63 static void init_write_state_machine(SSL *s);
64 static SUB_STATE_RETURN write_state_machine(SSL *s);
66 OSSL_HANDSHAKE_STATE SSL_get_state(const SSL *ssl)
68 return ssl->statem.hand_state;
71 int SSL_in_init(const SSL *s)
73 return s->statem.in_init;
76 int SSL_is_init_finished(const SSL *s)
78 return !(s->statem.in_init) && (s->statem.hand_state == TLS_ST_OK);
81 int SSL_in_before(const SSL *s)
84 * Historically being "in before" meant before anything had happened. In the
85 * current code though we remain in the "before" state for a while after we
86 * have started the handshake process (e.g. as a server waiting for the
87 * first message to arrive). There "in before" is taken to mean "in before"
88 * and not started any handshake process yet.
90 return (s->statem.hand_state == TLS_ST_BEFORE)
91 && (s->statem.state == MSG_FLOW_UNINITED);
95 * Clear the state machine state and reset back to MSG_FLOW_UNINITED
97 void ossl_statem_clear(SSL *s)
99 s->statem.state = MSG_FLOW_UNINITED;
100 s->statem.hand_state = TLS_ST_BEFORE;
101 s->statem.in_init = 1;
102 s->statem.no_cert_verify = 0;
106 * Set the state machine up ready for a renegotiation handshake
108 void ossl_statem_set_renegotiate(SSL *s)
110 s->statem.in_init = 1;
111 s->statem.request_state = TLS_ST_SW_HELLO_REQ;
115 * Put the state machine into an error state and send an alert if appropriate.
116 * This is a permanent error for the current connection.
118 void ossl_statem_fatal(SSL *s, int al, int func, int reason, const char *file,
121 ERR_put_error(ERR_LIB_SSL, func, reason, file, line);
122 /* We shouldn't call SSLfatal() twice. Once is enough */
123 if (s->statem.in_init && s->statem.state == MSG_FLOW_ERROR)
125 s->statem.in_init = 1;
126 s->statem.state = MSG_FLOW_ERROR;
127 if (al != SSL_AD_NO_ALERT
128 && s->statem.enc_write_state != ENC_WRITE_STATE_INVALID)
129 ssl3_send_alert(s, SSL3_AL_FATAL, al);
133 * This macro should only be called if we are already expecting to be in
134 * a fatal error state. We verify that we are, and set it if not (this would
137 #define check_fatal(s, f) \
139 if (!ossl_assert((s)->statem.in_init \
140 && (s)->statem.state == MSG_FLOW_ERROR)) \
141 SSLfatal(s, SSL_AD_INTERNAL_ERROR, (f), \
142 SSL_R_MISSING_FATAL); \
146 * Discover whether the current connection is in the error state.
148 * Valid return values are:
152 int ossl_statem_in_error(const SSL *s)
154 if (s->statem.state == MSG_FLOW_ERROR)
160 void ossl_statem_set_in_init(SSL *s, int init)
162 s->statem.in_init = init;
165 int ossl_statem_get_in_handshake(SSL *s)
167 return s->statem.in_handshake;
170 void ossl_statem_set_in_handshake(SSL *s, int inhand)
173 s->statem.in_handshake++;
175 s->statem.in_handshake--;
178 /* Are we in a sensible state to skip over unreadable early data? */
179 int ossl_statem_skip_early_data(SSL *s)
181 if (s->ext.early_data != SSL_EARLY_DATA_REJECTED)
185 || s->statem.hand_state != TLS_ST_EARLY_DATA
186 || s->hello_retry_request == SSL_HRR_COMPLETE)
193 * Called when we are in SSL_read*(), SSL_write*(), or SSL_accept()
194 * /SSL_connect()/SSL_do_handshake(). Used to test whether we are in an early
195 * data state and whether we should attempt to move the handshake on if so.
196 * |sending| is 1 if we are attempting to send data (SSL_write*()), 0 if we are
197 * attempting to read data (SSL_read*()), or -1 if we are in SSL_do_handshake()
200 void ossl_statem_check_finish_init(SSL *s, int sending)
203 if (s->statem.hand_state == TLS_ST_PENDING_EARLY_DATA_END
204 || s->statem.hand_state == TLS_ST_EARLY_DATA) {
205 ossl_statem_set_in_init(s, 1);
206 if (s->early_data_state == SSL_EARLY_DATA_WRITE_RETRY) {
208 * SSL_connect() or SSL_do_handshake() has been called directly.
209 * We don't allow any more writing of early data.
211 s->early_data_state = SSL_EARLY_DATA_FINISHED_WRITING;
214 } else if (!s->server) {
215 if ((sending && (s->statem.hand_state == TLS_ST_PENDING_EARLY_DATA_END
216 || s->statem.hand_state == TLS_ST_EARLY_DATA)
217 && s->early_data_state != SSL_EARLY_DATA_WRITING)
218 || (!sending && s->statem.hand_state == TLS_ST_EARLY_DATA)) {
219 ossl_statem_set_in_init(s, 1);
221 * SSL_write() has been called directly. We don't allow any more
222 * writing of early data.
224 if (sending && s->early_data_state == SSL_EARLY_DATA_WRITE_RETRY)
225 s->early_data_state = SSL_EARLY_DATA_FINISHED_WRITING;
228 if (s->early_data_state == SSL_EARLY_DATA_FINISHED_READING
229 && s->statem.hand_state == TLS_ST_EARLY_DATA)
230 ossl_statem_set_in_init(s, 1);
234 void ossl_statem_set_hello_verify_done(SSL *s)
236 s->statem.state = MSG_FLOW_UNINITED;
237 s->statem.in_init = 1;
239 * This will get reset (briefly) back to TLS_ST_BEFORE when we enter
240 * state_machine() because |state| is MSG_FLOW_UNINITED, but until then any
241 * calls to SSL_in_before() will return false. Also calls to
242 * SSL_state_string() and SSL_state_string_long() will return something
245 s->statem.hand_state = TLS_ST_SR_CLNT_HELLO;
248 int ossl_statem_connect(SSL *s)
250 return state_machine(s, 0);
253 int ossl_statem_accept(SSL *s)
255 return state_machine(s, 1);
258 typedef void (*info_cb) (const SSL *, int, int);
260 static info_cb get_callback(SSL *s)
262 if (s->info_callback != NULL)
263 return s->info_callback;
264 else if (s->ctx->info_callback != NULL)
265 return s->ctx->info_callback;
271 * The main message flow state machine. We start in the MSG_FLOW_UNINITED or
272 * MSG_FLOW_FINISHED state and finish in MSG_FLOW_FINISHED. Valid states and
273 * transitions are as follows:
275 * MSG_FLOW_UNINITED MSG_FLOW_FINISHED
277 * +-----------------------+
279 * MSG_FLOW_WRITING <---> MSG_FLOW_READING
287 * We may exit at any point due to an error or NBIO event. If an NBIO event
288 * occurs then we restart at the point we left off when we are recalled.
289 * MSG_FLOW_WRITING and MSG_FLOW_READING have sub-state machines associated with them.
291 * In addition to the above there is also the MSG_FLOW_ERROR state. We can move
292 * into that state at any point in the event that an irrecoverable error occurs.
294 * Valid return values are:
298 static int state_machine(SSL *s, int server)
301 void (*cb) (const SSL *ssl, int type, int val) = NULL;
302 OSSL_STATEM *st = &s->statem;
306 if (st->state == MSG_FLOW_ERROR) {
307 /* Shouldn't have been called if we're already in the error state */
314 cb = get_callback(s);
317 if (!SSL_in_init(s) || SSL_in_before(s)) {
319 * If we are stateless then we already called SSL_clear() - don't do
320 * it again and clear the STATELESS flag itself.
322 if ((s->s3->flags & TLS1_FLAGS_STATELESS) == 0 && !SSL_clear(s))
325 #ifndef OPENSSL_NO_SCTP
326 if (SSL_IS_DTLS(s) && BIO_dgram_is_sctp(SSL_get_wbio(s))) {
328 * Notify SCTP BIO socket to enter handshake mode and prevent stream
329 * identifier other than 0.
331 BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_SET_IN_HANDSHAKE,
332 st->in_handshake, NULL);
336 /* Initialise state machine */
337 if (st->state == MSG_FLOW_UNINITED
338 || st->state == MSG_FLOW_FINISHED) {
339 if (st->state == MSG_FLOW_UNINITED) {
340 st->hand_state = TLS_ST_BEFORE;
341 st->request_state = TLS_ST_BEFORE;
346 cb(s, SSL_CB_HANDSHAKE_START, 1);
349 * Fatal errors in this block don't send an alert because we have
350 * failed to even initialise properly. Sending an alert is probably
354 if (SSL_IS_DTLS(s)) {
355 if ((s->version & 0xff00) != (DTLS1_VERSION & 0xff00) &&
356 (server || (s->version & 0xff00) != (DTLS1_BAD_VER & 0xff00))) {
357 SSLfatal(s, SSL_AD_NO_ALERT, SSL_F_STATE_MACHINE,
358 ERR_R_INTERNAL_ERROR);
362 if ((s->version >> 8) != SSL3_VERSION_MAJOR) {
363 SSLfatal(s, SSL_AD_NO_ALERT, SSL_F_STATE_MACHINE,
364 ERR_R_INTERNAL_ERROR);
369 if (!ssl_security(s, SSL_SECOP_VERSION, 0, s->version, NULL)) {
370 SSLfatal(s, SSL_AD_NO_ALERT, SSL_F_STATE_MACHINE,
371 ERR_R_INTERNAL_ERROR);
375 if (s->init_buf == NULL) {
376 if ((buf = BUF_MEM_new()) == NULL) {
377 SSLfatal(s, SSL_AD_NO_ALERT, SSL_F_STATE_MACHINE,
378 ERR_R_INTERNAL_ERROR);
381 if (!BUF_MEM_grow(buf, SSL3_RT_MAX_PLAIN_LENGTH)) {
382 SSLfatal(s, SSL_AD_NO_ALERT, SSL_F_STATE_MACHINE,
383 ERR_R_INTERNAL_ERROR);
390 if (!ssl3_setup_buffers(s)) {
391 SSLfatal(s, SSL_AD_NO_ALERT, SSL_F_STATE_MACHINE,
392 ERR_R_INTERNAL_ERROR);
398 * Should have been reset by tls_process_finished, too.
400 s->s3->change_cipher_spec = 0;
403 * Ok, we now need to push on a buffering BIO ...but not with
406 #ifndef OPENSSL_NO_SCTP
407 if (!SSL_IS_DTLS(s) || !BIO_dgram_is_sctp(SSL_get_wbio(s)))
409 if (!ssl_init_wbio_buffer(s)) {
410 SSLfatal(s, SSL_AD_NO_ALERT, SSL_F_STATE_MACHINE,
411 ERR_R_INTERNAL_ERROR);
415 if ((SSL_in_before(s))
417 if (!tls_setup_handshake(s)) {
418 /* SSLfatal() already called */
422 if (SSL_IS_FIRST_HANDSHAKE(s))
423 st->read_state_first_init = 1;
426 st->state = MSG_FLOW_WRITING;
427 init_write_state_machine(s);
430 while (st->state != MSG_FLOW_FINISHED) {
431 if (st->state == MSG_FLOW_READING) {
432 ssret = read_state_machine(s);
433 if (ssret == SUB_STATE_FINISHED) {
434 st->state = MSG_FLOW_WRITING;
435 init_write_state_machine(s);
440 } else if (st->state == MSG_FLOW_WRITING) {
441 ssret = write_state_machine(s);
442 if (ssret == SUB_STATE_FINISHED) {
443 st->state = MSG_FLOW_READING;
444 init_read_state_machine(s);
445 } else if (ssret == SUB_STATE_END_HANDSHAKE) {
446 st->state = MSG_FLOW_FINISHED;
453 check_fatal(s, SSL_F_STATE_MACHINE);
454 SSLerr(SSL_F_STATE_MACHINE, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
464 #ifndef OPENSSL_NO_SCTP
465 if (SSL_IS_DTLS(s) && BIO_dgram_is_sctp(SSL_get_wbio(s))) {
467 * Notify SCTP BIO socket to leave handshake mode and allow stream
468 * identifier other than 0.
470 BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_SET_IN_HANDSHAKE,
471 st->in_handshake, NULL);
478 cb(s, SSL_CB_ACCEPT_EXIT, ret);
480 cb(s, SSL_CB_CONNECT_EXIT, ret);
486 * Initialise the MSG_FLOW_READING sub-state machine
488 static void init_read_state_machine(SSL *s)
490 OSSL_STATEM *st = &s->statem;
492 st->read_state = READ_STATE_HEADER;
495 static int grow_init_buf(SSL *s, size_t size) {
497 size_t msg_offset = (char *)s->init_msg - s->init_buf->data;
499 if (!BUF_MEM_grow_clean(s->init_buf, (int)size))
502 if (size < msg_offset)
505 s->init_msg = s->init_buf->data + msg_offset;
511 * This function implements the sub-state machine when the message flow is in
512 * MSG_FLOW_READING. The valid sub-states and transitions are:
514 * READ_STATE_HEADER <--+<-------------+
517 * READ_STATE_BODY -----+-->READ_STATE_POST_PROCESS
519 * +----------------------------+
521 * [SUB_STATE_FINISHED]
523 * READ_STATE_HEADER has the responsibility for reading in the message header
524 * and transitioning the state of the handshake state machine.
526 * READ_STATE_BODY reads in the rest of the message and then subsequently
529 * READ_STATE_POST_PROCESS is an optional step that may occur if some post
530 * processing activity performed on the message may block.
532 * Any of the above states could result in an NBIO event occurring in which case
533 * control returns to the calling application. When this function is recalled we
534 * will resume in the same state where we left off.
536 static SUB_STATE_RETURN read_state_machine(SSL *s)
538 OSSL_STATEM *st = &s->statem;
541 int (*transition) (SSL *s, int mt);
543 MSG_PROCESS_RETURN(*process_message) (SSL *s, PACKET *pkt);
544 WORK_STATE(*post_process_message) (SSL *s, WORK_STATE wst);
545 size_t (*max_message_size) (SSL *s);
546 void (*cb) (const SSL *ssl, int type, int val) = NULL;
548 cb = get_callback(s);
551 transition = ossl_statem_server_read_transition;
552 process_message = ossl_statem_server_process_message;
553 max_message_size = ossl_statem_server_max_message_size;
554 post_process_message = ossl_statem_server_post_process_message;
556 transition = ossl_statem_client_read_transition;
557 process_message = ossl_statem_client_process_message;
558 max_message_size = ossl_statem_client_max_message_size;
559 post_process_message = ossl_statem_client_post_process_message;
562 if (st->read_state_first_init) {
564 st->read_state_first_init = 0;
568 switch (st->read_state) {
569 case READ_STATE_HEADER:
570 /* Get the state the peer wants to move to */
571 if (SSL_IS_DTLS(s)) {
573 * In DTLS we get the whole message in one go - header and body
575 ret = dtls_get_message(s, &mt, &len);
577 ret = tls_get_message_header(s, &mt);
581 /* Could be non-blocking IO */
582 return SUB_STATE_ERROR;
586 /* Notify callback of an impending state change */
588 cb(s, SSL_CB_ACCEPT_LOOP, 1);
590 cb(s, SSL_CB_CONNECT_LOOP, 1);
593 * Validate that we are allowed to move to the new state and move
594 * to that state if so
596 if (!transition(s, mt))
597 return SUB_STATE_ERROR;
599 if (s->s3->tmp.message_size > max_message_size(s)) {
600 SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_F_READ_STATE_MACHINE,
601 SSL_R_EXCESSIVE_MESSAGE_SIZE);
602 return SUB_STATE_ERROR;
605 /* dtls_get_message already did this */
607 && s->s3->tmp.message_size > 0
608 && !grow_init_buf(s, s->s3->tmp.message_size
609 + SSL3_HM_HEADER_LENGTH)) {
610 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_READ_STATE_MACHINE,
612 return SUB_STATE_ERROR;
615 st->read_state = READ_STATE_BODY;
618 case READ_STATE_BODY:
619 if (!SSL_IS_DTLS(s)) {
620 /* We already got this above for DTLS */
621 ret = tls_get_message_body(s, &len);
623 /* Could be non-blocking IO */
624 return SUB_STATE_ERROR;
629 if (!PACKET_buf_init(&pkt, s->init_msg, len)) {
630 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_READ_STATE_MACHINE,
631 ERR_R_INTERNAL_ERROR);
632 return SUB_STATE_ERROR;
634 ret = process_message(s, &pkt);
636 /* Discard the packet data */
640 case MSG_PROCESS_ERROR:
641 check_fatal(s, SSL_F_READ_STATE_MACHINE);
642 return SUB_STATE_ERROR;
644 case MSG_PROCESS_FINISHED_READING:
645 if (SSL_IS_DTLS(s)) {
648 return SUB_STATE_FINISHED;
650 case MSG_PROCESS_CONTINUE_PROCESSING:
651 st->read_state = READ_STATE_POST_PROCESS;
652 st->read_state_work = WORK_MORE_A;
656 st->read_state = READ_STATE_HEADER;
661 case READ_STATE_POST_PROCESS:
662 st->read_state_work = post_process_message(s, st->read_state_work);
663 switch (st->read_state_work) {
665 check_fatal(s, SSL_F_READ_STATE_MACHINE);
670 return SUB_STATE_ERROR;
672 case WORK_FINISHED_CONTINUE:
673 st->read_state = READ_STATE_HEADER;
676 case WORK_FINISHED_STOP:
677 if (SSL_IS_DTLS(s)) {
680 return SUB_STATE_FINISHED;
685 /* Shouldn't happen */
686 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_READ_STATE_MACHINE,
687 ERR_R_INTERNAL_ERROR);
688 return SUB_STATE_ERROR;
694 * Send a previously constructed message to the peer.
696 static int statem_do_write(SSL *s)
698 OSSL_STATEM *st = &s->statem;
700 if (st->hand_state == TLS_ST_CW_CHANGE
701 || st->hand_state == TLS_ST_SW_CHANGE) {
703 return dtls1_do_write(s, SSL3_RT_CHANGE_CIPHER_SPEC);
705 return ssl3_do_write(s, SSL3_RT_CHANGE_CIPHER_SPEC);
707 return ssl_do_write(s);
712 * Initialise the MSG_FLOW_WRITING sub-state machine
714 static void init_write_state_machine(SSL *s)
716 OSSL_STATEM *st = &s->statem;
718 st->write_state = WRITE_STATE_TRANSITION;
722 * This function implements the sub-state machine when the message flow is in
723 * MSG_FLOW_WRITING. The valid sub-states and transitions are:
725 * +-> WRITE_STATE_TRANSITION ------> [SUB_STATE_FINISHED]
728 * | WRITE_STATE_PRE_WORK -----> [SUB_STATE_END_HANDSHAKE]
734 * | WRITE_STATE_POST_WORK
738 * WRITE_STATE_TRANSITION transitions the state of the handshake state machine
740 * WRITE_STATE_PRE_WORK performs any work necessary to prepare the later
741 * sending of the message. This could result in an NBIO event occurring in
742 * which case control returns to the calling application. When this function
743 * is recalled we will resume in the same state where we left off.
745 * WRITE_STATE_SEND sends the message and performs any work to be done after
748 * WRITE_STATE_POST_WORK performs any work necessary after the sending of the
749 * message has been completed. As for WRITE_STATE_PRE_WORK this could also
750 * result in an NBIO event.
752 static SUB_STATE_RETURN write_state_machine(SSL *s)
754 OSSL_STATEM *st = &s->statem;
756 WRITE_TRAN(*transition) (SSL *s);
757 WORK_STATE(*pre_work) (SSL *s, WORK_STATE wst);
758 WORK_STATE(*post_work) (SSL *s, WORK_STATE wst);
759 int (*get_construct_message_f) (SSL *s, WPACKET *pkt,
760 int (**confunc) (SSL *s, WPACKET *pkt),
762 void (*cb) (const SSL *ssl, int type, int val) = NULL;
763 int (*confunc) (SSL *s, WPACKET *pkt);
767 cb = get_callback(s);
770 transition = ossl_statem_server_write_transition;
771 pre_work = ossl_statem_server_pre_work;
772 post_work = ossl_statem_server_post_work;
773 get_construct_message_f = ossl_statem_server_construct_message;
775 transition = ossl_statem_client_write_transition;
776 pre_work = ossl_statem_client_pre_work;
777 post_work = ossl_statem_client_post_work;
778 get_construct_message_f = ossl_statem_client_construct_message;
782 switch (st->write_state) {
783 case WRITE_STATE_TRANSITION:
785 /* Notify callback of an impending state change */
787 cb(s, SSL_CB_ACCEPT_LOOP, 1);
789 cb(s, SSL_CB_CONNECT_LOOP, 1);
791 switch (transition(s)) {
792 case WRITE_TRAN_CONTINUE:
793 st->write_state = WRITE_STATE_PRE_WORK;
794 st->write_state_work = WORK_MORE_A;
797 case WRITE_TRAN_FINISHED:
798 return SUB_STATE_FINISHED;
801 case WRITE_TRAN_ERROR:
802 check_fatal(s, SSL_F_WRITE_STATE_MACHINE);
803 return SUB_STATE_ERROR;
807 case WRITE_STATE_PRE_WORK:
808 switch (st->write_state_work = pre_work(s, st->write_state_work)) {
810 check_fatal(s, SSL_F_WRITE_STATE_MACHINE);
815 return SUB_STATE_ERROR;
817 case WORK_FINISHED_CONTINUE:
818 st->write_state = WRITE_STATE_SEND;
821 case WORK_FINISHED_STOP:
822 return SUB_STATE_END_HANDSHAKE;
824 if (!get_construct_message_f(s, &pkt, &confunc, &mt)) {
825 /* SSLfatal() already called */
826 return SUB_STATE_ERROR;
828 if (mt == SSL3_MT_DUMMY) {
829 /* Skip construction and sending. This isn't a "real" state */
830 st->write_state = WRITE_STATE_POST_WORK;
831 st->write_state_work = WORK_MORE_A;
834 if (!WPACKET_init(&pkt, s->init_buf)
835 || !ssl_set_handshake_header(s, &pkt, mt)) {
836 WPACKET_cleanup(&pkt);
837 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_WRITE_STATE_MACHINE,
838 ERR_R_INTERNAL_ERROR);
839 return SUB_STATE_ERROR;
841 if (confunc != NULL && !confunc(s, &pkt)) {
842 WPACKET_cleanup(&pkt);
843 check_fatal(s, SSL_F_WRITE_STATE_MACHINE);
844 return SUB_STATE_ERROR;
846 if (!ssl_close_construct_packet(s, &pkt, mt)
847 || !WPACKET_finish(&pkt)) {
848 WPACKET_cleanup(&pkt);
849 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_WRITE_STATE_MACHINE,
850 ERR_R_INTERNAL_ERROR);
851 return SUB_STATE_ERROR;
856 case WRITE_STATE_SEND:
857 if (SSL_IS_DTLS(s) && st->use_timer) {
858 dtls1_start_timer(s);
860 ret = statem_do_write(s);
862 return SUB_STATE_ERROR;
864 st->write_state = WRITE_STATE_POST_WORK;
865 st->write_state_work = WORK_MORE_A;
868 case WRITE_STATE_POST_WORK:
869 switch (st->write_state_work = post_work(s, st->write_state_work)) {
871 check_fatal(s, SSL_F_WRITE_STATE_MACHINE);
876 return SUB_STATE_ERROR;
878 case WORK_FINISHED_CONTINUE:
879 st->write_state = WRITE_STATE_TRANSITION;
882 case WORK_FINISHED_STOP:
883 return SUB_STATE_END_HANDSHAKE;
888 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_WRITE_STATE_MACHINE,
889 ERR_R_INTERNAL_ERROR);
890 return SUB_STATE_ERROR;
896 * Flush the write BIO
898 int statem_flush(SSL *s)
900 s->rwstate = SSL_WRITING;
901 if (BIO_flush(s->wbio) <= 0) {
904 s->rwstate = SSL_NOTHING;
910 * Called by the record layer to determine whether application data is
911 * allowed to be received in the current handshake state or not.
914 * 1: Yes (application data allowed)
915 * 0: No (application data not allowed)
917 int ossl_statem_app_data_allowed(SSL *s)
919 OSSL_STATEM *st = &s->statem;
921 if (st->state == MSG_FLOW_UNINITED)
924 if (!s->s3->in_read_app_data || (s->s3->total_renegotiations == 0))
929 * If we're a server and we haven't got as far as writing our
930 * ServerHello yet then we allow app data
932 if (st->hand_state == TLS_ST_BEFORE
933 || st->hand_state == TLS_ST_SR_CLNT_HELLO)
937 * If we're a client and we haven't read the ServerHello yet then we
940 if (st->hand_state == TLS_ST_CW_CLNT_HELLO)
948 * This function returns 1 if TLS exporter is ready to export keying
949 * material, or 0 if otherwise.
951 int ossl_statem_export_allowed(SSL *s)
953 return s->s3->previous_server_finished_len != 0
954 && s->statem.hand_state != TLS_ST_SW_FINISHED;
958 * Return 1 if early TLS exporter is ready to export keying material,
961 int ossl_statem_export_early_allowed(SSL *s)
964 * The early exporter secret is only present on the server if we
965 * have accepted early_data. It is present on the client as long
966 * as we have sent early_data.
968 return s->ext.early_data == SSL_EARLY_DATA_ACCEPTED
969 || (!s->server && s->ext.early_data != SSL_EARLY_DATA_NOT_SENT);