/* 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.

 */

#include "apr_strings.h"

#include "ap_config.h"

#include "ap_provider.h"

#include "httpd.h"

#include "http_config.h"

#include "http_core.h"

#include "http_log.h"

#include "http_protocol.h"

#include "http_request.h"

#include "mod_auth.h"

typedef struct {

        int dummy;  /* just here to stop compiler warnings for now. */

} authz_user_config_rec;

static void *create_authz_user_dir_config(apr_pool_t *p, char *d)

{

    authz_user_config_rec *conf = apr_palloc(p, sizeof(*conf));

    return conf;

}

static const command_rec authz_user_cmds[] =

{

    {NULL}

};

module AP_MODULE_DECLARE_DATA authz_user_module;

static authz_status user_check_authorization(request_rec *r,

                                             const char *require_args,

                                             const void *parsed_require_args)

{

    const char *err = NULL;

    const ap_expr_info_t *expr = parsed_require_args;

    const char *require;

    const char *t, *w;

    if (!r->user) {

        return AUTHZ_DENIED_NO_USER;

    }

    require = ap_expr_str_exec(r, expr, &err;;

    if (err) {

        ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r, APLOGNO(02594)

                      "authz_user authorize: require user: Can't "

                      "evaluate require expression: %s", err);

        return AUTHZ_DENIED;

    }

    t = require;

    while ((w = ap_getword_conf(r->pool, &t)) && w[0]) {

        if (!strcmp(r->user, w)) {

            return AUTHZ_GRANTED;

        }

    }

    ap_log_rerror(APLOG_MARK, APLOG_DEBUG, 0, r, APLOGNO(01663)

                  "access to %s failed, reason: user '%s' does not meet "

                  "'require'ments for user to be allowed access",

                  r->uri, r->user);

    return AUTHZ_DENIED;

}

static authz_status validuser_check_authorization(request_rec *r,

                                                  const char *require_line,

                                                  const void *parsed_require_line)

{

    if (!r->user) {

        return AUTHZ_DENIED_NO_USER;

    }

    return AUTHZ_GRANTED;

}

static const char *user_parse_config(cmd_parms *cmd, const char *require_line,

                                     const void **parsed_require_line)

{

    const char *expr_err = NULL;

    ap_expr_info_t *expr;

    expr = ap_expr_parse_cmd(cmd, require_line, AP_EXPR_FLAG_STRING_RESULT,

            &expr_err, NULL);

    if (expr_err)

        return apr_pstrcat(cmd->temp_pool,

                           "Cannot parse expression in require line: ",

                           expr_err, NULL);

    *parsed_require_line = expr;

    return NULL;

}

static const authz_provider authz_user_provider =

{

    &user_check_authorization,

    &user_parse_config,

};

static const authz_provider authz_validuser_provider =

{

    &validuser_check_authorization,

    NULL,

};

static void register_hooks(apr_pool_t *p)

{

    ap_register_auth_provider(p, AUTHZ_PROVIDER_GROUP, "user",

                              AUTHZ_PROVIDER_VERSION,

                              &authz_user_provider, AP_AUTH_INTERNAL_PER_CONF);

    ap_register_auth_provider(p, AUTHZ_PROVIDER_GROUP, "valid-user",

                              AUTHZ_PROVIDER_VERSION,

                              &authz_validuser_provider,

                              AP_AUTH_INTERNAL_PER_CONF);

}

AP_DECLARE_MODULE(authz_user) =

{

    STANDARD20_MODULE_STUFF,

    create_authz_user_dir_config, /* dir config creater */

    NULL,                         /* dir merger --- default is to override */

    NULL,                         /* server config */

    NULL,                         /* merge server config */

    authz_user_cmds,              /* command apr_table_t */

    register_hooks                /* register hooks */

};