2 * Copyright 2015-2017 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(SSL *s)
73 return s->statem.in_init;
76 int SSL_is_init_finished(SSL *s)
78 return !(s->statem.in_init) && (s->statem.hand_state == TLS_ST_OK);
81 int SSL_in_before(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 /* We shouldn't call SSLfatal() twice. Once is enough */
122 assert(s->statem.state != MSG_FLOW_ERROR);
123 s->statem.in_init = 1;
124 s->statem.state = MSG_FLOW_ERROR;
125 ERR_put_error(ERR_LIB_SSL, func, reason, file, line);
126 if (al != SSL_AD_NO_ALERT)
127 ssl3_send_alert(s, SSL3_AL_FATAL, al);
131 * This macro should only be called if we are already expecting to be in
132 * a fatal error state. We verify that we are, and set it if not (this would
135 #define check_fatal(s, f) \
137 if (!ossl_assert((s)->statem.in_init \
138 || (s)->statem.state != MSG_FLOW_ERROR)) \
139 SSLfatal(s, SSL_AD_INTERNAL_ERROR, (f), \
140 SSL_R_MISSING_FATAL); \
144 * Discover whether the current connection is in the error state.
146 * Valid return values are:
150 int ossl_statem_in_error(const SSL *s)
152 if (s->statem.state == MSG_FLOW_ERROR)
158 void ossl_statem_set_in_init(SSL *s, int init)
160 s->statem.in_init = init;
163 int ossl_statem_get_in_handshake(SSL *s)
165 return s->statem.in_handshake;
168 void ossl_statem_set_in_handshake(SSL *s, int inhand)
171 s->statem.in_handshake++;
173 s->statem.in_handshake--;
176 /* Are we in a sensible state to skip over unreadable early data? */
177 int ossl_statem_skip_early_data(SSL *s)
179 if (s->ext.early_data != SSL_EARLY_DATA_REJECTED)
182 if (!s->server || s->statem.hand_state != TLS_ST_EARLY_DATA)
189 * Called when we are in SSL_read*(), SSL_write*(), or SSL_accept()
190 * /SSL_connect()/SSL_do_handshake(). Used to test whether we are in an early
191 * data state and whether we should attempt to move the handshake on if so.
192 * |sending| is 1 if we are attempting to send data (SSL_write*()), 0 if we are
193 * attempting to read data (SSL_read*()), or -1 if we are in SSL_do_handshake()
196 void ossl_statem_check_finish_init(SSL *s, int sending)
199 if (s->statem.hand_state == TLS_ST_PENDING_EARLY_DATA_END
200 || s->statem.hand_state == TLS_ST_EARLY_DATA) {
201 ossl_statem_set_in_init(s, 1);
202 if (s->early_data_state == SSL_EARLY_DATA_WRITE_RETRY) {
204 * SSL_connect() or SSL_do_handshake() has been called directly.
205 * We don't allow any more writing of early data.
207 s->early_data_state = SSL_EARLY_DATA_FINISHED_WRITING;
210 } else if (!s->server) {
211 if ((sending && (s->statem.hand_state == TLS_ST_PENDING_EARLY_DATA_END
212 || s->statem.hand_state == TLS_ST_EARLY_DATA)
213 && s->early_data_state != SSL_EARLY_DATA_WRITING)
214 || (!sending && s->statem.hand_state == TLS_ST_EARLY_DATA)) {
215 ossl_statem_set_in_init(s, 1);
217 * SSL_write() has been called directly. We don't allow any more
218 * writing of early data.
220 if (sending && s->early_data_state == SSL_EARLY_DATA_WRITE_RETRY)
221 s->early_data_state = SSL_EARLY_DATA_FINISHED_WRITING;
224 if (s->early_data_state == SSL_EARLY_DATA_FINISHED_READING
225 && s->statem.hand_state == TLS_ST_EARLY_DATA)
226 ossl_statem_set_in_init(s, 1);
230 void ossl_statem_set_hello_verify_done(SSL *s)
232 s->statem.state = MSG_FLOW_UNINITED;
233 s->statem.in_init = 1;
235 * This will get reset (briefly) back to TLS_ST_BEFORE when we enter
236 * state_machine() because |state| is MSG_FLOW_UNINITED, but until then any
237 * calls to SSL_in_before() will return false. Also calls to
238 * SSL_state_string() and SSL_state_string_long() will return something
241 s->statem.hand_state = TLS_ST_SR_CLNT_HELLO;
244 int ossl_statem_connect(SSL *s)
246 return state_machine(s, 0);
249 int ossl_statem_accept(SSL *s)
251 return state_machine(s, 1);
254 typedef void (*info_cb) (const SSL *, int, int);
256 static info_cb get_callback(SSL *s)
258 if (s->info_callback != NULL)
259 return s->info_callback;
260 else if (s->ctx->info_callback != NULL)
261 return s->ctx->info_callback;
267 * The main message flow state machine. We start in the MSG_FLOW_UNINITED or
268 * MSG_FLOW_FINISHED state and finish in MSG_FLOW_FINISHED. Valid states and
269 * transitions are as follows:
271 * MSG_FLOW_UNINITED MSG_FLOW_FINISHED
273 * +-----------------------+
275 * MSG_FLOW_WRITING <---> MSG_FLOW_READING
283 * We may exit at any point due to an error or NBIO event. If an NBIO event
284 * occurs then we restart at the point we left off when we are recalled.
285 * MSG_FLOW_WRITING and MSG_FLOW_READING have sub-state machines associated with them.
287 * In addition to the above there is also the MSG_FLOW_ERROR state. We can move
288 * into that state at any point in the event that an irrecoverable error occurs.
290 * Valid return values are:
294 static int state_machine(SSL *s, int server)
297 void (*cb) (const SSL *ssl, int type, int val) = NULL;
298 OSSL_STATEM *st = &s->statem;
302 if (st->state == MSG_FLOW_ERROR) {
303 /* Shouldn't have been called if we're already in the error state */
310 cb = get_callback(s);
313 if (!SSL_in_init(s) || SSL_in_before(s)) {
317 #ifndef OPENSSL_NO_SCTP
318 if (SSL_IS_DTLS(s) && BIO_dgram_is_sctp(SSL_get_wbio(s))) {
320 * Notify SCTP BIO socket to enter handshake mode and prevent stream
321 * identifier other than 0.
323 BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_SET_IN_HANDSHAKE,
324 st->in_handshake, NULL);
328 /* Initialise state machine */
329 if (st->state == MSG_FLOW_UNINITED
330 || st->state == MSG_FLOW_FINISHED) {
331 if (st->state == MSG_FLOW_UNINITED) {
332 st->hand_state = TLS_ST_BEFORE;
333 st->request_state = TLS_ST_BEFORE;
338 cb(s, SSL_CB_HANDSHAKE_START, 1);
341 * Fatal errors in this block don't send an alert because we have
342 * failed to even initialise properly. Sending an alert is probably
346 if (SSL_IS_DTLS(s)) {
347 if ((s->version & 0xff00) != (DTLS1_VERSION & 0xff00) &&
348 (server || (s->version & 0xff00) != (DTLS1_BAD_VER & 0xff00))) {
349 SSLfatal(s, SSL_AD_NO_ALERT, SSL_F_STATE_MACHINE,
350 ERR_R_INTERNAL_ERROR);
354 if ((s->version >> 8) != SSL3_VERSION_MAJOR) {
355 SSLfatal(s, SSL_AD_NO_ALERT, SSL_F_STATE_MACHINE,
356 ERR_R_INTERNAL_ERROR);
361 if (!ssl_security(s, SSL_SECOP_VERSION, 0, s->version, NULL)) {
362 SSLfatal(s, SSL_AD_NO_ALERT, SSL_F_STATE_MACHINE,
363 ERR_R_INTERNAL_ERROR);
367 if (s->init_buf == NULL) {
368 if ((buf = BUF_MEM_new()) == NULL) {
369 SSLfatal(s, SSL_AD_NO_ALERT, SSL_F_STATE_MACHINE,
370 ERR_R_INTERNAL_ERROR);
373 if (!BUF_MEM_grow(buf, SSL3_RT_MAX_PLAIN_LENGTH)) {
374 SSLfatal(s, SSL_AD_NO_ALERT, SSL_F_STATE_MACHINE,
375 ERR_R_INTERNAL_ERROR);
382 if (!ssl3_setup_buffers(s)) {
383 SSLfatal(s, SSL_AD_NO_ALERT, SSL_F_STATE_MACHINE,
384 ERR_R_INTERNAL_ERROR);
390 * Should have been reset by tls_process_finished, too.
392 s->s3->change_cipher_spec = 0;
395 * Ok, we now need to push on a buffering BIO ...but not with
398 #ifndef OPENSSL_NO_SCTP
399 if (!SSL_IS_DTLS(s) || !BIO_dgram_is_sctp(SSL_get_wbio(s)))
401 if (!ssl_init_wbio_buffer(s)) {
402 SSLfatal(s, SSL_AD_NO_ALERT, SSL_F_STATE_MACHINE,
403 ERR_R_INTERNAL_ERROR);
407 if ((SSL_in_before(s))
409 if (!tls_setup_handshake(s)) {
410 /* SSLfatal() already called */
414 if (SSL_IS_FIRST_HANDSHAKE(s))
415 st->read_state_first_init = 1;
418 st->state = MSG_FLOW_WRITING;
419 init_write_state_machine(s);
422 while (st->state != MSG_FLOW_FINISHED) {
423 if (st->state == MSG_FLOW_READING) {
424 ssret = read_state_machine(s);
425 if (ssret == SUB_STATE_FINISHED) {
426 st->state = MSG_FLOW_WRITING;
427 init_write_state_machine(s);
432 } else if (st->state == MSG_FLOW_WRITING) {
433 ssret = write_state_machine(s);
434 if (ssret == SUB_STATE_FINISHED) {
435 st->state = MSG_FLOW_READING;
436 init_read_state_machine(s);
437 } else if (ssret == SUB_STATE_END_HANDSHAKE) {
438 st->state = MSG_FLOW_FINISHED;
445 check_fatal(s, SSL_F_STATE_MACHINE);
446 SSLerr(SSL_F_STATE_MACHINE, ERR_R_INTERNAL_ERROR);
456 #ifndef OPENSSL_NO_SCTP
457 if (SSL_IS_DTLS(s) && BIO_dgram_is_sctp(SSL_get_wbio(s))) {
459 * Notify SCTP BIO socket to leave handshake mode and allow stream
460 * identifier other than 0.
462 BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_SET_IN_HANDSHAKE,
463 st->in_handshake, NULL);
470 cb(s, SSL_CB_ACCEPT_EXIT, ret);
472 cb(s, SSL_CB_CONNECT_EXIT, ret);
478 * Initialise the MSG_FLOW_READING sub-state machine
480 static void init_read_state_machine(SSL *s)
482 OSSL_STATEM *st = &s->statem;
484 st->read_state = READ_STATE_HEADER;
487 static int grow_init_buf(SSL *s, size_t size) {
489 size_t msg_offset = (char *)s->init_msg - s->init_buf->data;
491 if (!BUF_MEM_grow_clean(s->init_buf, (int)size))
494 if (size < msg_offset)
497 s->init_msg = s->init_buf->data + msg_offset;
503 * This function implements the sub-state machine when the message flow is in
504 * MSG_FLOW_READING. The valid sub-states and transitions are:
506 * READ_STATE_HEADER <--+<-------------+
509 * READ_STATE_BODY -----+-->READ_STATE_POST_PROCESS
511 * +----------------------------+
513 * [SUB_STATE_FINISHED]
515 * READ_STATE_HEADER has the responsibility for reading in the message header
516 * and transitioning the state of the handshake state machine.
518 * READ_STATE_BODY reads in the rest of the message and then subsequently
521 * READ_STATE_POST_PROCESS is an optional step that may occur if some post
522 * processing activity performed on the message may block.
524 * Any of the above states could result in an NBIO event occurring in which case
525 * control returns to the calling application. When this function is recalled we
526 * will resume in the same state where we left off.
528 static SUB_STATE_RETURN read_state_machine(SSL *s)
530 OSSL_STATEM *st = &s->statem;
533 int (*transition) (SSL *s, int mt);
535 MSG_PROCESS_RETURN(*process_message) (SSL *s, PACKET *pkt);
536 WORK_STATE(*post_process_message) (SSL *s, WORK_STATE wst);
537 size_t (*max_message_size) (SSL *s);
538 void (*cb) (const SSL *ssl, int type, int val) = NULL;
540 cb = get_callback(s);
543 transition = ossl_statem_server_read_transition;
544 process_message = ossl_statem_server_process_message;
545 max_message_size = ossl_statem_server_max_message_size;
546 post_process_message = ossl_statem_server_post_process_message;
548 transition = ossl_statem_client_read_transition;
549 process_message = ossl_statem_client_process_message;
550 max_message_size = ossl_statem_client_max_message_size;
551 post_process_message = ossl_statem_client_post_process_message;
554 if (st->read_state_first_init) {
556 st->read_state_first_init = 0;
560 switch (st->read_state) {
561 case READ_STATE_HEADER:
562 /* Get the state the peer wants to move to */
563 if (SSL_IS_DTLS(s)) {
565 * In DTLS we get the whole message in one go - header and body
567 ret = dtls_get_message(s, &mt, &len);
569 ret = tls_get_message_header(s, &mt);
573 /* Could be non-blocking IO */
574 return SUB_STATE_ERROR;
578 /* Notify callback of an impending state change */
580 cb(s, SSL_CB_ACCEPT_LOOP, 1);
582 cb(s, SSL_CB_CONNECT_LOOP, 1);
585 * Validate that we are allowed to move to the new state and move
586 * to that state if so
588 if (!transition(s, mt)) {
589 check_fatal(s, SSL_F_READ_STATE_MACHINE);
590 return SUB_STATE_ERROR;
593 if (s->s3->tmp.message_size > max_message_size(s)) {
594 SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER, SSL_F_READ_STATE_MACHINE,
595 SSL_R_EXCESSIVE_MESSAGE_SIZE);
596 return SUB_STATE_ERROR;
599 /* dtls_get_message already did this */
601 && s->s3->tmp.message_size > 0
602 && !grow_init_buf(s, s->s3->tmp.message_size
603 + SSL3_HM_HEADER_LENGTH)) {
604 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_READ_STATE_MACHINE,
606 return SUB_STATE_ERROR;
609 st->read_state = READ_STATE_BODY;
612 case READ_STATE_BODY:
613 if (!SSL_IS_DTLS(s)) {
614 /* We already got this above for DTLS */
615 ret = tls_get_message_body(s, &len);
617 /* Could be non-blocking IO */
618 return SUB_STATE_ERROR;
623 if (!PACKET_buf_init(&pkt, s->init_msg, len)) {
624 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_READ_STATE_MACHINE,
625 ERR_R_INTERNAL_ERROR);
626 return SUB_STATE_ERROR;
628 ret = process_message(s, &pkt);
630 /* Discard the packet data */
634 case MSG_PROCESS_ERROR:
635 check_fatal(s, SSL_F_READ_STATE_MACHINE);
636 return SUB_STATE_ERROR;
638 case MSG_PROCESS_FINISHED_READING:
639 if (SSL_IS_DTLS(s)) {
642 return SUB_STATE_FINISHED;
644 case MSG_PROCESS_CONTINUE_PROCESSING:
645 st->read_state = READ_STATE_POST_PROCESS;
646 st->read_state_work = WORK_MORE_A;
650 st->read_state = READ_STATE_HEADER;
655 case READ_STATE_POST_PROCESS:
656 st->read_state_work = post_process_message(s, st->read_state_work);
657 switch (st->read_state_work) {
659 check_fatal(s, SSL_F_READ_STATE_MACHINE);
664 return SUB_STATE_ERROR;
666 case WORK_FINISHED_CONTINUE:
667 st->read_state = READ_STATE_HEADER;
670 case WORK_FINISHED_STOP:
671 if (SSL_IS_DTLS(s)) {
674 return SUB_STATE_FINISHED;
679 /* Shouldn't happen */
680 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_READ_STATE_MACHINE,
681 ERR_R_INTERNAL_ERROR);
682 return SUB_STATE_ERROR;
688 * Send a previously constructed message to the peer.
690 static int statem_do_write(SSL *s)
692 OSSL_STATEM *st = &s->statem;
694 if (st->hand_state == TLS_ST_CW_CHANGE
695 || st->hand_state == TLS_ST_SW_CHANGE) {
697 return dtls1_do_write(s, SSL3_RT_CHANGE_CIPHER_SPEC);
699 return ssl3_do_write(s, SSL3_RT_CHANGE_CIPHER_SPEC);
701 return ssl_do_write(s);
706 * Initialise the MSG_FLOW_WRITING sub-state machine
708 static void init_write_state_machine(SSL *s)
710 OSSL_STATEM *st = &s->statem;
712 st->write_state = WRITE_STATE_TRANSITION;
716 * This function implements the sub-state machine when the message flow is in
717 * MSG_FLOW_WRITING. The valid sub-states and transitions are:
719 * +-> WRITE_STATE_TRANSITION ------> [SUB_STATE_FINISHED]
722 * | WRITE_STATE_PRE_WORK -----> [SUB_STATE_END_HANDSHAKE]
728 * | WRITE_STATE_POST_WORK
732 * WRITE_STATE_TRANSITION transitions the state of the handshake state machine
734 * WRITE_STATE_PRE_WORK performs any work necessary to prepare the later
735 * sending of the message. This could result in an NBIO event occurring in
736 * which case control returns to the calling application. When this function
737 * is recalled we will resume in the same state where we left off.
739 * WRITE_STATE_SEND sends the message and performs any work to be done after
742 * WRITE_STATE_POST_WORK performs any work necessary after the sending of the
743 * message has been completed. As for WRITE_STATE_PRE_WORK this could also
744 * result in an NBIO event.
746 static SUB_STATE_RETURN write_state_machine(SSL *s)
748 OSSL_STATEM *st = &s->statem;
750 WRITE_TRAN(*transition) (SSL *s);
751 WORK_STATE(*pre_work) (SSL *s, WORK_STATE wst);
752 WORK_STATE(*post_work) (SSL *s, WORK_STATE wst);
753 int (*get_construct_message_f) (SSL *s, WPACKET *pkt,
754 int (**confunc) (SSL *s, WPACKET *pkt),
756 void (*cb) (const SSL *ssl, int type, int val) = NULL;
757 int (*confunc) (SSL *s, WPACKET *pkt);
761 cb = get_callback(s);
764 transition = ossl_statem_server_write_transition;
765 pre_work = ossl_statem_server_pre_work;
766 post_work = ossl_statem_server_post_work;
767 get_construct_message_f = ossl_statem_server_construct_message;
769 transition = ossl_statem_client_write_transition;
770 pre_work = ossl_statem_client_pre_work;
771 post_work = ossl_statem_client_post_work;
772 get_construct_message_f = ossl_statem_client_construct_message;
776 switch (st->write_state) {
777 case WRITE_STATE_TRANSITION:
779 /* Notify callback of an impending state change */
781 cb(s, SSL_CB_ACCEPT_LOOP, 1);
783 cb(s, SSL_CB_CONNECT_LOOP, 1);
785 switch (transition(s)) {
786 case WRITE_TRAN_CONTINUE:
787 st->write_state = WRITE_STATE_PRE_WORK;
788 st->write_state_work = WORK_MORE_A;
791 case WRITE_TRAN_FINISHED:
792 return SUB_STATE_FINISHED;
795 case WRITE_TRAN_ERROR:
796 check_fatal(s, SSL_F_WRITE_STATE_MACHINE);
797 return SUB_STATE_ERROR;
801 case WRITE_STATE_PRE_WORK:
802 switch (st->write_state_work = pre_work(s, st->write_state_work)) {
804 check_fatal(s, SSL_F_WRITE_STATE_MACHINE);
809 return SUB_STATE_ERROR;
811 case WORK_FINISHED_CONTINUE:
812 st->write_state = WRITE_STATE_SEND;
815 case WORK_FINISHED_STOP:
816 return SUB_STATE_END_HANDSHAKE;
818 if (!get_construct_message_f(s, &pkt, &confunc, &mt)) {
819 /* SSLfatal() already called */
820 return SUB_STATE_ERROR;
822 if (mt == SSL3_MT_DUMMY) {
823 /* Skip construction and sending. This isn't a "real" state */
824 st->write_state = WRITE_STATE_POST_WORK;
825 st->write_state_work = WORK_MORE_A;
828 if (!WPACKET_init(&pkt, s->init_buf)
829 || !ssl_set_handshake_header(s, &pkt, mt)) {
830 WPACKET_cleanup(&pkt);
831 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_WRITE_STATE_MACHINE,
832 ERR_R_INTERNAL_ERROR);
833 return SUB_STATE_ERROR;
835 if (confunc != NULL && !confunc(s, &pkt)) {
836 WPACKET_cleanup(&pkt);
837 check_fatal(s, SSL_F_WRITE_STATE_MACHINE);
838 return SUB_STATE_ERROR;
840 if (!ssl_close_construct_packet(s, &pkt, mt)
841 || !WPACKET_finish(&pkt)) {
842 WPACKET_cleanup(&pkt);
843 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_WRITE_STATE_MACHINE,
844 ERR_R_INTERNAL_ERROR);
845 return SUB_STATE_ERROR;
850 case WRITE_STATE_SEND:
851 if (SSL_IS_DTLS(s) && st->use_timer) {
852 dtls1_start_timer(s);
854 ret = statem_do_write(s);
856 return SUB_STATE_ERROR;
858 st->write_state = WRITE_STATE_POST_WORK;
859 st->write_state_work = WORK_MORE_A;
862 case WRITE_STATE_POST_WORK:
863 switch (st->write_state_work = post_work(s, st->write_state_work)) {
865 check_fatal(s, SSL_F_WRITE_STATE_MACHINE);
870 return SUB_STATE_ERROR;
872 case WORK_FINISHED_CONTINUE:
873 st->write_state = WRITE_STATE_TRANSITION;
876 case WORK_FINISHED_STOP:
877 return SUB_STATE_END_HANDSHAKE;
882 SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_WRITE_STATE_MACHINE,
883 ERR_R_INTERNAL_ERROR);
884 return SUB_STATE_ERROR;
890 * Flush the write BIO
892 int statem_flush(SSL *s)
894 s->rwstate = SSL_WRITING;
895 if (BIO_flush(s->wbio) <= 0) {
898 s->rwstate = SSL_NOTHING;
904 * Called by the record layer to determine whether application data is
905 * allowed to be received in the current handshake state or not.
908 * 1: Yes (application data allowed)
909 * 0: No (application data not allowed)
911 int ossl_statem_app_data_allowed(SSL *s)
913 OSSL_STATEM *st = &s->statem;
915 if (st->state == MSG_FLOW_UNINITED)
918 if (!s->s3->in_read_app_data || (s->s3->total_renegotiations == 0))
923 * If we're a server and we haven't got as far as writing our
924 * ServerHello yet then we allow app data
926 if (st->hand_state == TLS_ST_BEFORE
927 || st->hand_state == TLS_ST_SR_CLNT_HELLO)
931 * If we're a client and we haven't read the ServerHello yet then we
934 if (st->hand_state == TLS_ST_CW_CLNT_HELLO)