modules/ssl/ssl_engine_mutex.c

/* Copyright 2001-2004 The Apache Software Foundation
 *
 * Licensed 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"
#if !defined(OS2) && !defined(WIN32) && !defined(BEOS) && !defined(NETWARE)
#include "unixd.h"
#define MOD_SSL_SET_MUTEX_PERMS /* XXX Apache should define something */
#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 MOD_SSL_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 global mutex 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 global mutex lock");
        return FALSE;
    }
    return TRUE;
}