/*

 * Copyright 1995-2021 The OpenSSL Project Authors. All Rights Reserved.

 *

 * Licensed under the Apache License 2.0 (the "License").  You may not use

 * this file except in compliance with the License.  You can obtain a copy

 * in the file LICENSE in the source distribution or at

 * https://www.openssl.org/source/license.html

 */

#include "ssl_local.h"

int ssl3_do_change_cipher_spec(SSL_CONNECTION *s)

{

    int i;

    SSL *ssl = SSL_CONNECTION_GET_SSL(s);

    if (s->server)

        i = SSL3_CHANGE_CIPHER_SERVER_READ;

    else

        i = SSL3_CHANGE_CIPHER_CLIENT_READ;

    if (s->s3.tmp.key_block == NULL) {

        if (s->session == NULL || s->session->master_key_length == 0) {

            /* might happen if dtls1_read_bytes() calls this */

            ERR_raise(ERR_LIB_SSL, SSL_R_CCS_RECEIVED_EARLY);

            return 0;

        }

        s->session->cipher = s->s3.tmp.new_cipher;

        if (!ssl->method->ssl3_enc->setup_key_block(s)) {

            /* SSLfatal() already called */

            return 0;

        }

    }

    if (!ssl->method->ssl3_enc->change_cipher_state(s, i)) {

        /* SSLfatal() already called */

        return 0;

    }

    return 1;

}

int ssl3_send_alert(SSL_CONNECTION *s, int level, int desc)

{

    SSL *ssl = SSL_CONNECTION_GET_SSL(s);

    /* Map tls/ssl alert value to correct one */

    if (SSL_CONNECTION_TREAT_AS_TLS13(s))

        desc = tls13_alert_code(desc);

    else

        desc = ssl->method->ssl3_enc->alert_value(desc);

    if (s->version == SSL3_VERSION && desc == SSL_AD_PROTOCOL_VERSION)

        desc = SSL_AD_HANDSHAKE_FAILURE; /* SSL 3.0 does not have

                                          * protocol_version alerts */

    if (desc < 0)

        return -1;

    if (s->shutdown & SSL_SENT_SHUTDOWN && desc != SSL_AD_CLOSE_NOTIFY)

        return -1;

    /* If a fatal one, remove from cache */

    if ((level == SSL3_AL_FATAL) && (s->session != NULL))

        SSL_CTX_remove_session(s->session_ctx, s->session);

    s->s3.alert_dispatch = SSL_ALERT_DISPATCH_PENDING;

    s->s3.send_alert[0] = level;

    s->s3.send_alert[1] = desc;

    if (!RECORD_LAYER_write_pending(&s->rlayer)) {

        /* data still being written out? */

        return ssl->method->ssl_dispatch_alert(ssl);

    }

    /*

     * else data is still being written out, we will get written some time in

     * the future

     */

    return -1;

}

int ssl3_dispatch_alert(SSL *s)

{

    int i, j;

    void (*cb) (const SSL *ssl, int type, int val) = NULL;

    SSL_CONNECTION *sc = SSL_CONNECTION_FROM_SSL(s);

    OSSL_RECORD_TEMPLATE templ;

    if (sc == NULL)

        return -1;

    if (sc->rlayer.wrlmethod == NULL) {

        /* No write record layer so we can't sent and alert. We just ignore it */

        sc->s3.alert_dispatch = SSL_ALERT_DISPATCH_NONE;

        return 1;

    }

    templ.type = SSL3_RT_ALERT;

    templ.version = (sc->version == TLS1_3_VERSION) ? TLS1_2_VERSION

                                                    : sc->version;

    if (SSL_get_state(s) == TLS_ST_CW_CLNT_HELLO

            && !sc->renegotiate

            && TLS1_get_version(s) > TLS1_VERSION

            && sc->hello_retry_request == SSL_HRR_NONE) {

        templ.version = TLS1_VERSION;

    }

    templ.buf = &sc->s3.send_alert[0];

    templ.buflen = 2;

    if (RECORD_LAYER_write_pending(&sc->rlayer)) {

        if (sc->s3.alert_dispatch != SSL_ALERT_DISPATCH_RETRY) {

            /*

             * We have a write pending but it wasn't from a previous call to

             * this function! Can we ever get here? Maybe via API misuse??

             * Give up.

             */

            sc->s3.alert_dispatch = SSL_ALERT_DISPATCH_NONE;

            return -1;

        }

        /* Retry what we've already got pending */

        i = HANDLE_RLAYER_WRITE_RETURN(sc,

                sc->rlayer.wrlmethod->retry_write_records(sc->rlayer.wrl));

        if (i <= 0) {

            /* Could be NBIO. Keep alert_dispatch as SSL_ALERT_DISPATCH_RETRY */

            return -1;

        }

        sc->rlayer.wpend_tot = 0;

        sc->s3.alert_dispatch = SSL_ALERT_DISPATCH_NONE;

        return 1;

    }

    i = HANDLE_RLAYER_WRITE_RETURN(sc,

            sc->rlayer.wrlmethod->write_records(sc->rlayer.wrl, &templ, 1));

    if (i <= 0) {

        sc->s3.alert_dispatch = SSL_ALERT_DISPATCH_RETRY;

        sc->rlayer.wpend_tot = templ.buflen;

        sc->rlayer.wpend_type = templ.type;

        sc->rlayer.wpend_buf = templ.buf;

    } else {

        /*

         * Alert sent to BIO - now flush. If the message does not get sent due

         * to non-blocking IO, we will not worry too much.

         */

        (void)BIO_flush(sc->wbio);

        sc->s3.alert_dispatch = SSL_ALERT_DISPATCH_NONE;

        if (sc->msg_callback)

            sc->msg_callback(1, sc->version, SSL3_RT_ALERT, sc->s3.send_alert,

                             2, s, sc->msg_callback_arg);

        if (sc->info_callback != NULL)

            cb = sc->info_callback;

        else if (s->ctx->info_callback != NULL)

            cb = s->ctx->info_callback;

        if (cb != NULL) {

            j = (sc->s3.send_alert[0] << 8) | sc->s3.send_alert[1];

            cb(s, SSL_CB_WRITE_ALERT, j);

        }

    }

    return i;

}