/* Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

/*                      _             _
 *  _ __ ___   ___   __| |    ___ ___| |  mod_ssl
 * | '_ ` _ \ / _ \ / _` |   / __/ __| |  Apache Interface to OpenSSL
 * | | | | | | (_) | (_| |   \__ \__ \ |
 * |_| |_| |_|\___/ \__,_|___|___/___/_|
 *                      |_____|
 *  ssl_engine_mutex.c
 *  Semaphore for Mutual Exclusion
 */
                             /* ``Real programmers confuse
                                  Christmas and Halloween
                                  because DEC 25 = OCT 31.''
                                             -- Unknown     */

#include "ssl_private.h"

#ifdef AP_NEED_SET_MUTEX_PERMS
#include "unixd.h"
#endif

int ssl_mutex_init(server_rec *s, apr_pool_t *p)
{
    SSLModConfigRec *mc = myModConfig(s);
    apr_status_t rv;

    if (mc->nMutexMode == SSL_MUTEXMODE_NONE)
        return TRUE;

    if (mc->pMutex) {
        return TRUE;
    }
    if ((rv = apr_global_mutex_create(&mc->pMutex, mc->szMutexFile,
                                      mc->nMutexMech, s->process->pool))
            != APR_SUCCESS) {
        if (mc->szMutexFile)
            ap_log_error(APLOG_MARK, APLOG_ERR, rv, s,
                         "Cannot create SSLMutex with file `%s'",
                         mc->szMutexFile);
        else
            ap_log_error(APLOG_MARK, APLOG_ERR, rv, s,
                         "Cannot create SSLMutex");
        return FALSE;
    }

#ifdef AP_NEED_SET_MUTEX_PERMS
    rv = unixd_set_global_mutex_perms(mc->pMutex);
    if (rv != APR_SUCCESS) {
        ap_log_error(APLOG_MARK, APLOG_ERR, rv, s,
                     "Could not set permissions on ssl_mutex; check User "
                     "and Group directives");
        return FALSE;
    }
#endif
    return TRUE;
}

int ssl_mutex_reinit(server_rec *s, apr_pool_t *p)
{
    SSLModConfigRec *mc = myModConfig(s);
    apr_status_t rv;

    if (mc->nMutexMode == SSL_MUTEXMODE_NONE)
        return TRUE;

    if ((rv = apr_global_mutex_child_init(&mc->pMutex,
                                    mc->szMutexFile, p)) != APR_SUCCESS) {
        if (mc->szMutexFile)
            ap_log_error(APLOG_MARK, APLOG_ERR, rv, s,
                         "Cannot reinit SSLMutex with file `%s'",
                         mc->szMutexFile);
        else
            ap_log_error(APLOG_MARK, APLOG_WARNING, rv, s,
                         "Cannot reinit SSLMutex");
        return FALSE;
    }
    return TRUE;
}

int ssl_mutex_on(server_rec *s)
{
    SSLModConfigRec *mc = myModConfig(s);
    apr_status_t rv;

    if (mc->nMutexMode == SSL_MUTEXMODE_NONE)
        return TRUE;
    if ((rv = apr_global_mutex_lock(mc->pMutex)) != APR_SUCCESS) {
        ap_log_error(APLOG_MARK, APLOG_WARNING, rv, s,
                     "Failed to acquire SSL session cache lock");
        return FALSE;
    }
    return TRUE;
}

int ssl_mutex_off(server_rec *s)
{
    SSLModConfigRec *mc = myModConfig(s);
    apr_status_t rv;

    if (mc->nMutexMode == SSL_MUTEXMODE_NONE)
        return TRUE;
    if ((rv = apr_global_mutex_unlock(mc->pMutex)) != APR_SUCCESS) {
        ap_log_error(APLOG_MARK, APLOG_WARNING, rv, s,
                     "Failed to release SSL session cache lock");
        return FALSE;
    }
    return TRUE;
}