| /* |
| * 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 occurring 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 occurring 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 |
