apache/modules/aaa/mod_authz_owner.c

   1 /* Licensed to the Apache Software Foundation (ASF) under one or more
   2  * contributor license agreements.  See the NOTICE file distributed with
   3  * this work for additional information regarding copyright ownership.
   4  * The ASF licenses this file to You under the Apache License, Version 2.0
   5  * (the "License"); you may not use this file except in compliance with
   6  * the License.  You may obtain a copy of the License at
   7  *
   8  *     http://www.apache.org/licenses/LICENSE-2.0
   9  *
  10  * Unless required by applicable law or agreed to in writing, software
  11  * distributed under the License is distributed on an "AS IS" BASIS,
  12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  13  * See the License for the specific language governing permissions and
  14  * limitations under the License.
  15  */
  16
  17 #include "apr_strings.h"
  18 #include "apr_file_info.h"
  19 #include "apr_user.h"
  20
  21 #include "ap_config.h"
  22 #include "ap_provider.h"
  23 #include "httpd.h"
  24 #include "http_config.h"
  25 #include "http_core.h"
  26 #include "http_log.h"
  27 #include "http_protocol.h"
  28 #include "http_request.h"
  29
  30 #include "mod_auth.h"
  31
  32 APR_DECLARE_OPTIONAL_FN(char*, authz_owner_get_file_group, (request_rec *r));
  33
  34 static const command_rec authz_owner_cmds[] =
  35 {
  36     {NULL}
  37 };
  38
  39 module AP_MODULE_DECLARE_DATA authz_owner_module;
  40
  41 static authz_status fileowner_check_authorization(request_rec *r,
  42                                              const char *require_args)
  43 {
  44     char *reason = NULL;
  45     apr_status_t status = 0;
  46
  47 #if !APR_HAS_USER
  48     reason = "'Require file-owner' is not supported on this platform.";
  49     ap_log_rerror(APLOG_MARK, APLOG_ERR, status, r,
  50                   "Authorization of user %s to access %s failed, reason: %s",
  51                   r->user, r->uri, reason ? reason : "unknown");
  52     return AUTHZ_DENIED;
  53 #else  /* APR_HAS_USER */
  54     char *owner = NULL;
  55     apr_finfo_t finfo;
  56
  57     if (!r->user) {
  58         ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r,
  59             "access to %s failed, reason: no authenticated user", r->uri);
  60         return AUTHZ_DENIED;
  61     }
  62
  63     if (!r->filename) {
  64         reason = "no filename available";
  65         ap_log_rerror(APLOG_MARK, APLOG_ERR, status, r,
  66                       "Authorization of user %s to access %s failed, reason: %s",
  67                       r->user, r->uri, reason ? reason : "unknown");
  68         return AUTHZ_DENIED;
  69     }
  70
  71     status = apr_stat(&finfo, r->filename, APR_FINFO_USER, r->pool);
  72     if (status != APR_SUCCESS) {
  73         reason = apr_pstrcat(r->pool, "could not stat file ",
  74                                 r->filename, NULL);
  75         ap_log_rerror(APLOG_MARK, APLOG_ERR, status, r,
  76                       "Authorization of user %s to access %s failed, reason: %s",
  77                       r->user, r->uri, reason ? reason : "unknown");
  78         return AUTHZ_DENIED;
  79     }
  80
  81     if (!(finfo.valid & APR_FINFO_USER)) {
  82         reason = "no file owner information available";
  83         ap_log_rerror(APLOG_MARK, APLOG_ERR, status, r,
  84                       "Authorization of user %s to access %s failed, reason: %s",
  85                       r->user, r->uri, reason ? reason : "unknown");
  86         return AUTHZ_DENIED;
  87     }
  88
  89     status = apr_uid_name_get(&owner, finfo.user, r->pool);
  90     if (status != APR_SUCCESS || !owner) {
  91         reason = "could not get name of file owner";
  92         ap_log_rerror(APLOG_MARK, APLOG_ERR, status, r,
  93                       "Authorization of user %s to access %s failed, reason: %s",
  94                       r->user, r->uri, reason ? reason : "unknown");
  95         return AUTHZ_DENIED;
  96     }
  97
  98     if (strcmp(owner, r->user)) {
  99         reason = apr_psprintf(r->pool, "file owner %s does not match.",
 100                                 owner);
 101         ap_log_rerror(APLOG_MARK, APLOG_ERR, status, r,
 102                       "Authorization of user %s to access %s failed, reason: %s",
 103                       r->user, r->uri, reason ? reason : "unknown");
 104         return AUTHZ_DENIED;
 105     }
 106
 107     /* this user is authorized */
 108     return AUTHZ_GRANTED;
 109 #endif /* APR_HAS_USER */
 110 }
 111
 112 static char *authz_owner_get_file_group(request_rec *r)
 113 {
 114     char *reason = NULL;
 115
 116     /* file-group only figures out the file's group and lets
 117     * other modules do the actual authorization (against a group file/db).
 118     * Thus, these modules have to hook themselves after
 119     * mod_authz_owner and of course recognize 'file-group', too.
 120     */
 121 #if !APR_HAS_USER
 122     return NULL;
 123 #else  /* APR_HAS_USER */
 124     char *group = NULL;
 125     apr_finfo_t finfo;
 126     apr_status_t status = 0;
 127
 128     if (!r->filename) {
 129         reason = "no filename available";
 130         ap_log_rerror(APLOG_MARK, APLOG_ERR, status, r,
 131                       "Authorization of user %s to access %s failed, reason: %s",
 132                       r->user, r->uri, reason ? reason : "unknown");
 133         return NULL;
 134     }
 135
 136     status = apr_stat(&finfo, r->filename, APR_FINFO_GROUP, r->pool);
 137     if (status != APR_SUCCESS) {
 138         reason = apr_pstrcat(r->pool, "could not stat file ",
 139                                 r->filename, NULL);
 140         ap_log_rerror(APLOG_MARK, APLOG_ERR, status, r,
 141                       "Authorization of user %s to access %s failed, reason: %s",
 142                       r->user, r->uri, reason ? reason : "unknown");
 143         return NULL;
 144     }
 145
 146     if (!(finfo.valid & APR_FINFO_GROUP)) {
 147         reason = "no file group information available";
 148         ap_log_rerror(APLOG_MARK, APLOG_ERR, status, r,
 149                       "Authorization of user %s to access %s failed, reason: %s",
 150                       r->user, r->uri, reason ? reason : "unknown");
 151         return NULL;
 152     }
 153
 154     status = apr_gid_name_get(&group, finfo.group, r->pool);
 155     if (status != APR_SUCCESS || !group) {
 156         reason = "could not get name of file group";
 157         ap_log_rerror(APLOG_MARK, APLOG_ERR, status, r,
 158                       "Authorization of user %s to access %s failed, reason: %s",
 159                       r->user, r->uri, reason ? reason : "unknown");
 160         return NULL;
 161     }
 162
 163     return group;
 164 #endif /* APR_HAS_USER */
 165 }
 166
 167 static const authz_provider authz_fileowner_provider =
 168 {
 169     &fileowner_check_authorization,
 170 };
 171
 172 static void register_hooks(apr_pool_t *p)
 173 {
 174     APR_REGISTER_OPTIONAL_FN(authz_owner_get_file_group);
 175
 176     ap_register_auth_provider(p, AUTHZ_PROVIDER_GROUP, "file-owner",
 177                               AUTHZ_PROVIDER_VERSION,
 178                               &authz_fileowner_provider,
 179                               AP_AUTH_INTERNAL_PER_CONF);
 180 }
 181
 182 module AP_MODULE_DECLARE_DATA authz_owner_module =
 183 {
 184     STANDARD20_MODULE_STUFF,
 185     NULL,                          /* dir config creater */
 186     NULL,                          /* dir merger --- default is to override */
 187     NULL,                          /* server config */
 188     NULL,                          /* merge server config */
 189     authz_owner_cmds,              /* command apr_table_t */
 190     register_hooks                 /* register hooks */
 191 };