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- /* ssl/statem/statem.c */
- /*
- * Written by Matt Caswell for the OpenSSL project.
- */
- /* ====================================================================
- * Copyright (c) 1998-2015 The OpenSSL Project. All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- *
- * 1. Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *
- * 2. Redistributions in binary form must reproduce the above copyright
- * notice, this list of conditions and the following disclaimer in
- * the documentation and/or other materials provided with the
- * distribution.
- *
- * 3. All advertising materials mentioning features or use of this
- * software must display the following acknowledgment:
- * "This product includes software developed by the OpenSSL Project
- * for use in the OpenSSL Toolkit. (http://www.openssl.org/)"
- *
- * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
- * endorse or promote products derived from this software without
- * prior written permission. For written permission, please contact
- * openssl-core@openssl.org.
- *
- * 5. Products derived from this software may not be called "OpenSSL"
- * nor may "OpenSSL" appear in their names without prior written
- * permission of the OpenSSL Project.
- *
- * 6. Redistributions of any form whatsoever must retain the following
- * acknowledgment:
- * "This product includes software developed by the OpenSSL Project
- * for use in the OpenSSL Toolkit (http://www.openssl.org/)"
- *
- * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
- * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
- * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
- * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR
- * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
- * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
- * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
- * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
- * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
- * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
- * OF THE POSSIBILITY OF SUCH DAMAGE.
- * ====================================================================
- *
- * This product includes cryptographic software written by Eric Young
- * (eay@cryptsoft.com). This product includes software written by Tim
- * Hudson (tjh@cryptsoft.com).
- *
- */
- #include <openssl/rand.h>
- #include "../ssl_locl.h"
- #include "statem_locl.h"
- /*
- * This file implements the SSL/TLS/DTLS state machines.
- *
- * There are two primary state machines:
- *
- * 1) Message flow state machine
- * 2) Handshake state machine
- *
- * The Message flow state machine controls the reading and sending of messages
- * including handling of non-blocking IO events, flushing of the underlying
- * write BIO, handling unexpected messages, etc. It is itself broken into two
- * separate sub-state machines which control reading and writing respectively.
- *
- * The Handshake state machine keeps track of the current SSL/TLS handshake
- * state. Transitions of the handshake state are the result of events that
- * occur within the Message flow state machine.
- *
- * Overall it looks like this:
- *
- * --------------------------------------------- -------------------
- * | | | |
- * | Message flow state machine | | |
- * | | | |
- * | -------------------- -------------------- | Transition | Handshake state |
- * | | MSG_FLOW_READING | | MSG_FLOW_WRITING | | Event | machine |
- * | | sub-state | | sub-state | |----------->| |
- * | | machine for | | machine for | | | |
- * | | reading messages | | writing messages | | | |
- * | -------------------- -------------------- | | |
- * | | | |
- * --------------------------------------------- -------------------
- *
- */
- /* Sub state machine return values */
- typedef enum {
- /* Something bad happened or NBIO */
- SUB_STATE_ERROR,
- /* Sub state finished go to the next sub state */
- SUB_STATE_FINISHED,
- /* Sub state finished and handshake was completed */
- SUB_STATE_END_HANDSHAKE
- } SUB_STATE_RETURN;
- static int state_machine(SSL *s, int server);
- static void init_read_state_machine(SSL *s);
- static SUB_STATE_RETURN read_state_machine(SSL *s);
- static void init_write_state_machine(SSL *s);
- static SUB_STATE_RETURN write_state_machine(SSL *s);
- OSSL_HANDSHAKE_STATE SSL_get_state(const SSL *ssl)
- {
- return ssl->statem.hand_state;
- }
- int SSL_in_init(SSL *s)
- {
- return s->statem.in_init;
- }
- int SSL_is_init_finished(SSL *s)
- {
- return !(s->statem.in_init) && (s->statem.hand_state == TLS_ST_OK);
- }
- int SSL_in_before(SSL *s)
- {
- /*
- * Historically being "in before" meant before anything had happened. In the
- * current code though we remain in the "before" state for a while after we
- * have started the handshake process (e.g. as a server waiting for the
- * first message to arrive). There "in before" is taken to mean "in before"
- * and not started any handshake process yet.
- */
- return (s->statem.hand_state == TLS_ST_BEFORE)
- && (s->statem.state == MSG_FLOW_UNINITED);
- }
- /*
- * Clear the state machine state and reset back to MSG_FLOW_UNINITED
- */
- void ossl_statem_clear(SSL *s)
- {
- s->statem.state = MSG_FLOW_UNINITED;
- s->statem.hand_state = TLS_ST_BEFORE;
- s->statem.in_init = 1;
- s->statem.no_cert_verify = 0;
- }
- /*
- * Set the state machine up ready for a renegotiation handshake
- */
- void ossl_statem_set_renegotiate(SSL *s)
- {
- s->statem.state = MSG_FLOW_RENEGOTIATE;
- s->statem.in_init = 1;
- }
- /*
- * Put the state machine into an error state. This is a permanent error for
- * the current connection.
- */
- void ossl_statem_set_error(SSL *s)
- {
- s->statem.state = MSG_FLOW_ERROR;
- }
- /*
- * Discover whether the current connection is in the error state.
- *
- * Valid return values are:
- * 1: Yes
- * 0: No
- */
- int ossl_statem_in_error(const SSL *s)
- {
- if (s->statem.state == MSG_FLOW_ERROR)
- return 1;
- return 0;
- }
- void ossl_statem_set_in_init(SSL *s, int init)
- {
- s->statem.in_init = init;
- }
- int ossl_statem_get_in_handshake(SSL *s)
- {
- return s->statem.in_handshake;
- }
- void ossl_statem_set_in_handshake(SSL *s, int inhand)
- {
- if (inhand)
- s->statem.in_handshake++;
- else
- s->statem.in_handshake--;
- }
- void ossl_statem_set_hello_verify_done(SSL *s)
- {
- s->statem.state = MSG_FLOW_UNINITED;
- s->statem.in_init = 1;
- /*
- * This will get reset (briefly) back to TLS_ST_BEFORE when we enter
- * state_machine() because |state| is MSG_FLOW_UNINITED, but until then any
- * calls to SSL_in_before() will return false. Also calls to
- * SSL_state_string() and SSL_state_string_long() will return something
- * sensible.
- */
- s->statem.hand_state = TLS_ST_SR_CLNT_HELLO;
- }
- int ossl_statem_connect(SSL *s) {
- return state_machine(s, 0);
- }
- int ossl_statem_accept(SSL *s)
- {
- return state_machine(s, 1);
- }
- static void (*get_callback(SSL *s))(const SSL *, int, int)
- {
- if (s->info_callback != NULL)
- return s->info_callback;
- else if (s->ctx->info_callback != NULL)
- return s->ctx->info_callback;
- return NULL;
- }
- /*
- * The main message flow state machine. We start in the MSG_FLOW_UNINITED or
- * MSG_FLOW_RENEGOTIATE state and finish in MSG_FLOW_FINISHED. Valid states and
- * transitions are as follows:
- *
- * MSG_FLOW_UNINITED MSG_FLOW_RENEGOTIATE
- * | |
- * +-----------------------+
- * v
- * MSG_FLOW_WRITING <---> MSG_FLOW_READING
- * |
- * V
- * MSG_FLOW_FINISHED
- * |
- * V
- * [SUCCESS]
- *
- * We may exit at any point due to an error or NBIO event. If an NBIO event
- * occurs then we restart at the point we left off when we are recalled.
- * MSG_FLOW_WRITING and MSG_FLOW_READING have sub-state machines associated with them.
- *
- * In addition to the above there is also the MSG_FLOW_ERROR state. We can move
- * into that state at any point in the event that an irrecoverable error occurs.
- *
- * Valid return values are:
- * 1: Success
- * <=0: NBIO or error
- */
- static int state_machine(SSL *s, int server)
- {
- BUF_MEM *buf = NULL;
- unsigned long Time = (unsigned long)time(NULL);
- void (*cb) (const SSL *ssl, int type, int val) = NULL;
- OSSL_STATEM *st = &s->statem;
- int ret = -1;
- int ssret;
- if (st->state == MSG_FLOW_ERROR) {
- /* Shouldn't have been called if we're already in the error state */
- return -1;
- }
- RAND_add(&Time, sizeof(Time), 0);
- ERR_clear_error();
- clear_sys_error();
- cb = get_callback(s);
- st->in_handshake++;
- if (!SSL_in_init(s) || SSL_in_before(s)) {
- if (!SSL_clear(s))
- return -1;
- }
- #ifndef OPENSSL_NO_SCTP
- if (SSL_IS_DTLS(s)) {
- /*
- * Notify SCTP BIO socket to enter handshake mode and prevent stream
- * identifier other than 0. Will be ignored if no SCTP is used.
- */
- BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_SET_IN_HANDSHAKE,
- st->in_handshake, NULL);
- }
- #endif
- #ifndef OPENSSL_NO_HEARTBEATS
- /*
- * If we're awaiting a HeartbeatResponse, pretend we already got and
- * don't await it anymore, because Heartbeats don't make sense during
- * handshakes anyway.
- */
- if (s->tlsext_hb_pending) {
- if (SSL_IS_DTLS(s))
- dtls1_stop_timer(s);
- s->tlsext_hb_pending = 0;
- s->tlsext_hb_seq++;
- }
- #endif
- /* Initialise state machine */
- if (st->state == MSG_FLOW_RENEGOTIATE) {
- s->renegotiate = 1;
- if (!server)
- s->ctx->stats.sess_connect_renegotiate++;
- }
- if (st->state == MSG_FLOW_UNINITED || st->state == MSG_FLOW_RENEGOTIATE) {
- if (st->state == MSG_FLOW_UNINITED) {
- st->hand_state = TLS_ST_BEFORE;
- }
- s->server = server;
- if (cb != NULL)
- cb(s, SSL_CB_HANDSHAKE_START, 1);
- if (SSL_IS_DTLS(s)) {
- if ((s->version & 0xff00) != (DTLS1_VERSION & 0xff00) &&
- (server
- || (s->version & 0xff00) != (DTLS1_BAD_VER & 0xff00))) {
- SSLerr(SSL_F_STATE_MACHINE, ERR_R_INTERNAL_ERROR);
- goto end;
- }
- } else {
- if ((s->version >> 8) != SSL3_VERSION_MAJOR) {
- SSLerr(SSL_F_STATE_MACHINE, ERR_R_INTERNAL_ERROR);
- goto end;
- }
- }
- if (!ssl_security(s, SSL_SECOP_VERSION, 0, s->version, NULL)) {
- SSLerr(SSL_F_STATE_MACHINE, SSL_R_VERSION_TOO_LOW);
- goto end;
- }
- if (s->init_buf == NULL) {
- if ((buf = BUF_MEM_new()) == NULL) {
- goto end;
- }
- if (!BUF_MEM_grow(buf, SSL3_RT_MAX_PLAIN_LENGTH)) {
- goto end;
- }
- s->init_buf = buf;
- buf = NULL;
- }
- if (!ssl3_setup_buffers(s)) {
- goto end;
- }
- s->init_num = 0;
- /*
- * Should have been reset by tls_process_finished, too.
- */
- s->s3->change_cipher_spec = 0;
- if (!server || st->state != MSG_FLOW_RENEGOTIATE) {
- /*
- * Ok, we now need to push on a buffering BIO ...but not with
- * SCTP
- */
- #ifndef OPENSSL_NO_SCTP
- if (!SSL_IS_DTLS(s) || !BIO_dgram_is_sctp(SSL_get_wbio(s)))
- #endif
- if (!ssl_init_wbio_buffer(s, server ? 1 : 0)) {
- goto end;
- }
- ssl3_init_finished_mac(s);
- }
- if (server) {
- if (st->state != MSG_FLOW_RENEGOTIATE) {
- s->ctx->stats.sess_accept++;
- } else if (!s->s3->send_connection_binding &&
- !(s->options &
- SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION)) {
- /*
- * Server attempting to renegotiate with client that doesn't
- * support secure renegotiation.
- */
- SSLerr(SSL_F_STATE_MACHINE,
- SSL_R_UNSAFE_LEGACY_RENEGOTIATION_DISABLED);
- ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_HANDSHAKE_FAILURE);
- ossl_statem_set_error(s);
- goto end;
- } else {
- /*
- * st->state == MSG_FLOW_RENEGOTIATE, we will just send a
- * HelloRequest
- */
- s->ctx->stats.sess_accept_renegotiate++;
- }
- } else {
- s->ctx->stats.sess_connect++;
- /* mark client_random uninitialized */
- memset(s->s3->client_random, 0, sizeof(s->s3->client_random));
- s->hit = 0;
- s->s3->tmp.cert_request = 0;
- if (SSL_IS_DTLS(s)) {
- st->use_timer = 1;
- }
- }
- st->state = MSG_FLOW_WRITING;
- init_write_state_machine(s);
- st->read_state_first_init = 1;
- }
- while(st->state != MSG_FLOW_FINISHED) {
- if(st->state == MSG_FLOW_READING) {
- ssret = read_state_machine(s);
- if (ssret == SUB_STATE_FINISHED) {
- st->state = MSG_FLOW_WRITING;
- init_write_state_machine(s);
- } else {
- /* NBIO or error */
- goto end;
- }
- } else if (st->state == MSG_FLOW_WRITING) {
- ssret = write_state_machine(s);
- if (ssret == SUB_STATE_FINISHED) {
- st->state = MSG_FLOW_READING;
- init_read_state_machine(s);
- } else if (ssret == SUB_STATE_END_HANDSHAKE) {
- st->state = MSG_FLOW_FINISHED;
- } else {
- /* NBIO or error */
- goto end;
- }
- } else {
- /* Error */
- ossl_statem_set_error(s);
- goto end;
- }
- }
- st->state = MSG_FLOW_UNINITED;
- ret = 1;
- end:
- st->in_handshake--;
- #ifndef OPENSSL_NO_SCTP
- if (SSL_IS_DTLS(s)) {
- /*
- * Notify SCTP BIO socket to leave handshake mode and allow stream
- * identifier other than 0. Will be ignored if no SCTP is used.
- */
- BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_SET_IN_HANDSHAKE,
- st->in_handshake, NULL);
- }
- #endif
- BUF_MEM_free(buf);
- if (cb != NULL) {
- if (server)
- cb(s, SSL_CB_ACCEPT_EXIT, ret);
- else
- cb(s, SSL_CB_CONNECT_EXIT, ret);
- }
- return ret;
- }
- /*
- * Initialise the MSG_FLOW_READING sub-state machine
- */
- static void init_read_state_machine(SSL *s)
- {
- OSSL_STATEM *st = &s->statem;
- st->read_state = READ_STATE_HEADER;
- }
- /*
- * This function implements the sub-state machine when the message flow is in
- * MSG_FLOW_READING. The valid sub-states and transitions are:
- *
- * READ_STATE_HEADER <--+<-------------+
- * | | |
- * v | |
- * READ_STATE_BODY -----+-->READ_STATE_POST_PROCESS
- * | |
- * +----------------------------+
- * v
- * [SUB_STATE_FINISHED]
- *
- * READ_STATE_HEADER has the responsibility for reading in the message header
- * and transitioning the state of the handshake state machine.
- *
- * READ_STATE_BODY reads in the rest of the message and then subsequently
- * processes it.
- *
- * READ_STATE_POST_PROCESS is an optional step that may occur if some post
- * processing activity performed on the message may block.
- *
- * Any of the above states could result in an NBIO event occuring in which case
- * control returns to the calling application. When this function is recalled we
- * will resume in the same state where we left off.
- */
- static SUB_STATE_RETURN read_state_machine(SSL *s) {
- OSSL_STATEM *st = &s->statem;
- int ret, mt;
- unsigned long len = 0;
- int (*transition)(SSL *s, int mt);
- PACKET pkt;
- MSG_PROCESS_RETURN (*process_message)(SSL *s, PACKET *pkt);
- WORK_STATE (*post_process_message)(SSL *s, WORK_STATE wst);
- unsigned long (*max_message_size)(SSL *s);
- void (*cb) (const SSL *ssl, int type, int val) = NULL;
- cb = get_callback(s);
- if(s->server) {
- transition = ossl_statem_server_read_transition;
- process_message = ossl_statem_server_process_message;
- max_message_size = ossl_statem_server_max_message_size;
- post_process_message = ossl_statem_server_post_process_message;
- } else {
- transition = ossl_statem_client_read_transition;
- process_message = ossl_statem_client_process_message;
- max_message_size = ossl_statem_client_max_message_size;
- post_process_message = ossl_statem_client_post_process_message;
- }
- if (st->read_state_first_init) {
- s->first_packet = 1;
- st->read_state_first_init = 0;
- }
- while(1) {
- switch(st->read_state) {
- case READ_STATE_HEADER:
- s->init_num = 0;
- /* Get the state the peer wants to move to */
- if (SSL_IS_DTLS(s)) {
- /*
- * In DTLS we get the whole message in one go - header and body
- */
- ret = dtls_get_message(s, &mt, &len);
- } else {
- ret = tls_get_message_header(s, &mt);
- }
- if (ret == 0) {
- /* Could be non-blocking IO */
- return SUB_STATE_ERROR;
- }
- if (cb != NULL) {
- /* Notify callback of an impending state change */
- if (s->server)
- cb(s, SSL_CB_ACCEPT_LOOP, 1);
- else
- cb(s, SSL_CB_CONNECT_LOOP, 1);
- }
- /*
- * Validate that we are allowed to move to the new state and move
- * to that state if so
- */
- if(!transition(s, mt)) {
- ssl3_send_alert(s, SSL3_AL_FATAL, SSL3_AD_UNEXPECTED_MESSAGE);
- SSLerr(SSL_F_READ_STATE_MACHINE, SSL_R_UNEXPECTED_MESSAGE);
- return SUB_STATE_ERROR;
- }
- if (s->s3->tmp.message_size > max_message_size(s)) {
- ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_ILLEGAL_PARAMETER);
- SSLerr(SSL_F_READ_STATE_MACHINE, SSL_R_EXCESSIVE_MESSAGE_SIZE);
- return SUB_STATE_ERROR;
- }
- st->read_state = READ_STATE_BODY;
- /* Fall through */
- case READ_STATE_BODY:
- if (!SSL_IS_DTLS(s)) {
- /* We already got this above for DTLS */
- ret = tls_get_message_body(s, &len);
- if (ret == 0) {
- /* Could be non-blocking IO */
- return SUB_STATE_ERROR;
- }
- }
- s->first_packet = 0;
- if (!PACKET_buf_init(&pkt, s->init_msg, len)) {
- ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR);
- SSLerr(SSL_F_READ_STATE_MACHINE, ERR_R_INTERNAL_ERROR);
- return SUB_STATE_ERROR;
- }
- ret = process_message(s, &pkt);
- if (ret == MSG_PROCESS_ERROR) {
- return SUB_STATE_ERROR;
- }
- if (ret == MSG_PROCESS_FINISHED_READING) {
- if (SSL_IS_DTLS(s)) {
- dtls1_stop_timer(s);
- }
- return SUB_STATE_FINISHED;
- }
- if (ret == MSG_PROCESS_CONTINUE_PROCESSING) {
- st->read_state = READ_STATE_POST_PROCESS;
- st->read_state_work = WORK_MORE_A;
- } else {
- st->read_state = READ_STATE_HEADER;
- }
- break;
- case READ_STATE_POST_PROCESS:
- st->read_state_work = post_process_message(s, st->read_state_work);
- switch(st->read_state_work) {
- default:
- return SUB_STATE_ERROR;
- case WORK_FINISHED_CONTINUE:
- st->read_state = READ_STATE_HEADER;
- break;
- case WORK_FINISHED_STOP:
- if (SSL_IS_DTLS(s)) {
- dtls1_stop_timer(s);
- }
- return SUB_STATE_FINISHED;
- }
- break;
- default:
- /* Shouldn't happen */
- ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR);
- SSLerr(SSL_F_READ_STATE_MACHINE, ERR_R_INTERNAL_ERROR);
- ossl_statem_set_error(s);
- return SUB_STATE_ERROR;
- }
- }
- }
- /*
- * Send a previously constructed message to the peer.
- */
- static int statem_do_write(SSL *s)
- {
- OSSL_STATEM *st = &s->statem;
- if (st->hand_state == TLS_ST_CW_CHANGE
- || st->hand_state == TLS_ST_SW_CHANGE) {
- if (SSL_IS_DTLS(s))
- return dtls1_do_write(s, SSL3_RT_CHANGE_CIPHER_SPEC);
- else
- return ssl3_do_write(s, SSL3_RT_CHANGE_CIPHER_SPEC);
- } else {
- return ssl_do_write(s);
- }
- }
- /*
- * Initialise the MSG_FLOW_WRITING sub-state machine
- */
- static void init_write_state_machine(SSL *s)
- {
- OSSL_STATEM *st = &s->statem;
- st->write_state = WRITE_STATE_TRANSITION;
- }
- /*
- * This function implements the sub-state machine when the message flow is in
- * MSG_FLOW_WRITING. The valid sub-states and transitions are:
- *
- * +-> WRITE_STATE_TRANSITION ------> [SUB_STATE_FINISHED]
- * | |
- * | v
- * | WRITE_STATE_PRE_WORK -----> [SUB_STATE_END_HANDSHAKE]
- * | |
- * | v
- * | WRITE_STATE_SEND
- * | |
- * | v
- * | WRITE_STATE_POST_WORK
- * | |
- * +-------------+
- *
- * WRITE_STATE_TRANSITION transitions the state of the handshake state machine
- * WRITE_STATE_PRE_WORK performs any work necessary to prepare the later
- * sending of the message. This could result in an NBIO event occuring in
- * which case control returns to the calling application. When this function
- * is recalled we will resume in the same state where we left off.
- *
- * WRITE_STATE_SEND sends the message and performs any work to be done after
- * sending.
- *
- * WRITE_STATE_POST_WORK performs any work necessary after the sending of the
- * message has been completed. As for WRITE_STATE_PRE_WORK this could also
- * result in an NBIO event.
- */
- static SUB_STATE_RETURN write_state_machine(SSL *s)
- {
- OSSL_STATEM *st = &s->statem;
- int ret;
- WRITE_TRAN (*transition)(SSL *s);
- WORK_STATE (*pre_work)(SSL *s, WORK_STATE wst);
- WORK_STATE (*post_work)(SSL *s, WORK_STATE wst);
- int (*construct_message)(SSL *s);
- void (*cb) (const SSL *ssl, int type, int val) = NULL;
- cb = get_callback(s);
- if(s->server) {
- transition = ossl_statem_server_write_transition;
- pre_work = ossl_statem_server_pre_work;
- post_work = ossl_statem_server_post_work;
- construct_message = ossl_statem_server_construct_message;
- } else {
- transition = ossl_statem_client_write_transition;
- pre_work = ossl_statem_client_pre_work;
- post_work = ossl_statem_client_post_work;
- construct_message = ossl_statem_client_construct_message;
- }
- while(1) {
- switch(st->write_state) {
- case WRITE_STATE_TRANSITION:
- if (cb != NULL) {
- /* Notify callback of an impending state change */
- if (s->server)
- cb(s, SSL_CB_ACCEPT_LOOP, 1);
- else
- cb(s, SSL_CB_CONNECT_LOOP, 1);
- }
- switch(transition(s)) {
- case WRITE_TRAN_CONTINUE:
- st->write_state = WRITE_STATE_PRE_WORK;
- st->write_state_work = WORK_MORE_A;
- break;
- case WRITE_TRAN_FINISHED:
- return SUB_STATE_FINISHED;
- break;
- default:
- return SUB_STATE_ERROR;
- }
- break;
- case WRITE_STATE_PRE_WORK:
- switch(st->write_state_work = pre_work(s, st->write_state_work)) {
- default:
- return SUB_STATE_ERROR;
- case WORK_FINISHED_CONTINUE:
- st->write_state = WRITE_STATE_SEND;
- break;
- case WORK_FINISHED_STOP:
- return SUB_STATE_END_HANDSHAKE;
- }
- if(construct_message(s) == 0)
- return SUB_STATE_ERROR;
- /* Fall through */
- case WRITE_STATE_SEND:
- if (SSL_IS_DTLS(s) && st->use_timer) {
- dtls1_start_timer(s);
- }
- ret = statem_do_write(s);
- if (ret <= 0) {
- return SUB_STATE_ERROR;
- }
- st->write_state = WRITE_STATE_POST_WORK;
- st->write_state_work = WORK_MORE_A;
- /* Fall through */
- case WRITE_STATE_POST_WORK:
- switch(st->write_state_work = post_work(s, st->write_state_work)) {
- default:
- return SUB_STATE_ERROR;
- case WORK_FINISHED_CONTINUE:
- st->write_state = WRITE_STATE_TRANSITION;
- break;
- case WORK_FINISHED_STOP:
- return SUB_STATE_END_HANDSHAKE;
- }
- break;
- default:
- return SUB_STATE_ERROR;
- }
- }
- }
- /*
- * Flush the write BIO
- */
- int statem_flush(SSL *s)
- {
- s->rwstate = SSL_WRITING;
- if (BIO_flush(s->wbio) <= 0) {
- return 0;
- }
- s->rwstate = SSL_NOTHING;
- return 1;
- }
- /*
- * Called by the record layer to determine whether application data is
- * allowed to be sent in the current handshake state or not.
- *
- * Return values are:
- * 1: Yes (application data allowed)
- * 0: No (application data not allowed)
- */
- int ossl_statem_app_data_allowed(SSL *s)
- {
- OSSL_STATEM *st = &s->statem;
- if (st->state == MSG_FLOW_UNINITED || st->state == MSG_FLOW_RENEGOTIATE)
- return 0;
- if (!s->s3->in_read_app_data || (s->s3->total_renegotiations == 0))
- return 0;
- if (s->server) {
- /*
- * If we're a server and we haven't got as far as writing our
- * ServerHello yet then we allow app data
- */
- if (st->hand_state == TLS_ST_BEFORE
- || st->hand_state == TLS_ST_SR_CLNT_HELLO)
- return 1;
- } else {
- /*
- * If we're a client and we haven't read the ServerHello yet then we
- * allow app data
- */
- if (st->hand_state == TLS_ST_CW_CLNT_HELLO)
- return 1;
- }
- return 0;
- }
- #ifndef OPENSSL_NO_SCTP
- /*
- * Set flag used by SCTP to determine whether we are in the read sock state
- */
- void ossl_statem_set_sctp_read_sock(SSL *s, int read_sock)
- {
- s->statem.in_sctp_read_sock = read_sock;
- }
- /*
- * Called by the record layer to determine whether we are in the read sock
- * state or not.
- *
- * Return values are:
- * 1: Yes (we are in the read sock state)
- * 0: No (we are not in the read sock state)
- */
- int ossl_statem_in_sctp_read_sock(SSL *s)
- {
- return s->statem.in_sctp_read_sock;
- }
- #endif
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