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_SHOULD_NOT_HAVE_BEEN_CALLED
);
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
)