You are viewing a plain text version of this content. The canonical link for it is here.
Posted to cvs@httpd.apache.org by nd...@apache.org on 2003/01/15 23:08:55 UTC

cvs commit: httpd-2.0/modules/aaa mod_authz_owner.c config.m4 mod_auth.h

nd          2003/01/15 14:08:54

  Modified:    modules/aaa config.m4 mod_auth.h
  Added:       modules/aaa mod_authz_owner.c
  Log:
  as announced and with no objections:
  mod_authz_owner: forward port of require file-owner/file-group functionality
  
  The goal of the module is to do all the neccessary file system work to
  figure out username and groupname. "Require file-owner" is completely
  resolved within the module. "file-group" is only determined there and the
  groupname will be extracted from the stat call and stored within the
  r->notes. Done that, the module will decline, so that the group database
  modules (mod_authz_groupfile, mod_authz_dbm) can verify the groupname with
  their lists.
  Thus every group module that supports the file-group requirement must be
  hooked after mod_authz_owner. They have to recognize "file-group" and read
  the groupname from r->notes. (If there's no name stored, the modules should
  ignore the file-group requirement). The backstopper module will do its work
  in worst case.
  
  not solved yet:
  - the module doesn't work as one could expect if the file doesn't exist in
    the first request round (consider MultiViews) (the 1.3 version has the
    same problem). I played around with some subrequest techniques, but got
    no helpful result. Is there any magic to recognize the actual resulting
    filename (if there is)?
  
  Revision  Changes    Path
  1.59      +1 -0      httpd-2.0/modules/aaa/config.m4
  
  Index: config.m4
  ===================================================================
  RCS file: /home/cvs/httpd-2.0/modules/aaa/config.m4,v
  retrieving revision 1.58
  retrieving revision 1.59
  diff -u -r1.58 -r1.59
  --- config.m4	28 Nov 2002 23:02:44 -0000	1.58
  +++ config.m4	15 Jan 2003 22:08:54 -0000	1.59
  @@ -26,6 +26,7 @@
   APACHE_MODULE(authz_groupfile, 'require group' authorization control, , , yes)
   APACHE_MODULE(authz_user, 'require user' authorization control, , , yes)
   APACHE_MODULE(authz_dbm, DBM-based authorization control, , , most)
  +APACHE_MODULE(authz_owner, 'require file-owner' authorization control, , , most)
   
   dnl - and just in case all of the above punt; a default handler to
   dnl keep the bad guys out.
  
  
  
  1.6       +2 -0      httpd-2.0/modules/aaa/mod_auth.h
  
  Index: mod_auth.h
  ===================================================================
  RCS file: /home/cvs/httpd-2.0/modules/aaa/mod_auth.h,v
  retrieving revision 1.5
  retrieving revision 1.6
  diff -u -r1.5 -r1.6
  --- mod_auth.h	20 Sep 2002 00:57:49 -0000	1.5
  +++ mod_auth.h	15 Jan 2003 22:08:54 -0000	1.6
  @@ -67,6 +67,8 @@
   
   #define AUTHN_PROVIDER_GROUP "authn"
   #define AUTHN_DEFAULT_PROVIDER "file"
  +    
  +#define AUTHZ_GROUP_NOTE "authz_group_note"
   
   typedef enum {
       AUTH_DENIED,
  
  
  
  1.1                  httpd-2.0/modules/aaa/mod_authz_owner.c
  
  Index: mod_authz_owner.c
  ===================================================================
  /* ====================================================================
   * The Apache Software License, Version 1.1
   *
   * Copyright (c) 2000-2002 The Apache Software Foundation.  All rights
   * reserved.
   *
   * Redistribution and use in source and binary forms, with or without
   * modification, are permitted provided that the following conditions
   * are met:
   *
   * 1. Redistributions of source code must retain the above copyright
   *    notice, this list of conditions and the following disclaimer.
   *
   * 2. Redistributions in binary form must reproduce the above copyright
   *    notice, this list of conditions and the following disclaimer in
   *    the documentation and/or other materials provided with the
   *    distribution.
   *
   * 3. The end-user documentation included with the redistribution,
   *    if any, must include the following acknowledgment:
   *       "This product includes software developed by the
   *        Apache Software Foundation (http://www.apache.org/)."
   *    Alternately, this acknowledgment may appear in the software itself,
   *    if and wherever such third-party acknowledgments normally appear.
   *
   * 4. The names "Apache" and "Apache Software Foundation" must
   *    not be used to endorse or promote products derived from this
   *    software without prior written permission. For written
   *    permission, please contact apache@apache.org.
   *
   * 5. Products derived from this software may not be called "Apache",
   *    nor may "Apache" appear in their name, without prior written
   *    permission of the Apache Software Foundation.
   *
   * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
   * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
   * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
   * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
   * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
   * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
   * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
   * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
   * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
   * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
   * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
   * SUCH DAMAGE.
   * ====================================================================
   *
   * This software consists of voluntary contributions made by many
   * individuals on behalf of the Apache Software Foundation.  For more
   * information on the Apache Software Foundation, please see
   * <http://www.apache.org/>.
   *
   * Portions of this software are based upon public domain software
   * originally written at the National Center for Supercomputing Applications,
   * University of Illinois, Urbana-Champaign.
   */
  
  /*
   * http_auth: authentication
   * 
   * Rob McCool
   * 
   * Adapted to Apache by rst.
   *
   * dirkx - Added Authoritative control to allow passing on to lower
   *         modules if and only if the userid is not known to this
   *         module. A known user with a faulty or absent password still
   *         causes an AuthRequired. The default is 'Authoritative', i.e.
   *         no control is passed along.
   */
  
  #include "apr_strings.h"
  #include "apr_file_info.h"
  #include "apr_user.h"
  
  #include "ap_config.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"     /* for AUTHZ_GROUP_NOTE */
  
  typedef struct {
      int authoritative;
  } authz_owner_config_rec;
  
  static void *create_authz_owner_dir_config(apr_pool_t *p, char *d)
  {
      authz_owner_config_rec *conf = apr_palloc(p, sizeof(*conf));
  
      conf->authoritative = 1; /* keep the fortress secure by default */
      return conf;
  }
  
  static const command_rec authz_owner_cmds[] =
  {
      AP_INIT_FLAG("AuthzOwnerAuthoritative", ap_set_flag_slot,
                   (void *)APR_OFFSETOF(authz_owner_config_rec, authoritative),
                   OR_AUTHCFG,
                   "Set to 'Off' to allow access control to be passed along to "
                   "lower modules. (default is On.)"),
      {NULL}
  };
  
  module AP_MODULE_DECLARE_DATA authz_owner_module;
  
  static int check_file_owner(request_rec *r)
  {
      authz_owner_config_rec *conf = ap_get_module_config(r->per_dir_config,
                                                          &authz_owner_module);
      int m = r->method_number;
      register int x;
      const char *t, *w;
      const apr_array_header_t *reqs_arr = ap_requires(r);
      require_line *reqs;
      int required_owner = 0;
      apr_status_t status = 0;
      char *reason = NULL;
  
      if (!reqs_arr) {
          return DECLINED;
      }
  
      reqs = (require_line *)reqs_arr->elts;
      for (x = 0; x < reqs_arr->nelts; x++) {
  
          /* if authoritative = On then break if a require already failed. */
          if (reason && conf->authoritative) {
              break;
          }
  
          if (!(reqs[x].method_mask & (AP_METHOD_BIT << m))) {
              continue;
          }
  
          t = reqs[x].requirement;
          w = ap_getword_white(r->pool, &t);
  
          if (!strcmp(w, "file-owner")) {
  #if !APR_HAS_USER
              if ((required_owner & ~1) && conf->authoritative) {
                  break;
              }
  
              required_owner |= 1; /* remember the requirement */
              reason = "'Require file-owner' is not supported on this platform.";
              continue;
  #else  /* APR_HAS_USER */
              char *owner = NULL;
              apr_finfo_t finfo;
  
              if ((required_owner & ~1) && conf->authoritative) {
                  break;
              }
  
              required_owner |= 1; /* remember the requirement */
  
              if (!r->filename) {
                  reason = "no filename available";
                  continue;
              }
  
              status = apr_stat(&finfo, r->filename, APR_FINFO_USER, r->pool);
              if (status != APR_SUCCESS) {
                  reason = apr_pstrcat(r->pool, "could not stat file ",
                                       r->filename, NULL);
                  continue;
              }
  
              if (!(finfo.valid & APR_FINFO_USER)) {
                  reason = "no file owner information available";
                  continue;
              }
  
              status = apr_uid_name_get(&owner, finfo.user, r->pool);
              if (status != APR_SUCCESS || !owner) {
                  reason = "could not get name of file owner";
                  continue;
              }
  
              if (strcmp(owner, r->user)) {
                  reason = apr_psprintf(r->pool, "file owner %s does not match.",
                                        owner);
                  continue;
              }
  
              /* this user is authorized */
              return OK;
  #endif /* APR_HAS_USER */
          }
  
          /* file-group only figures out the file's group and lets
           * other modules do the actual authorization (against a group file/db).
           * Thus, these modules have to hook themselves after
           * mod_authz_owner and of course recognize 'file-group', too.
           */
          if (!strcmp(w, "file-group")) {
  #if !APR_HAS_USER
              if ((required_owner & ~6) && conf->authoritative) {
                  break;
              }
  
              required_owner |= 2; /* remember the requirement */
              reason = "'Require file-group' is not supported on this platform.";
              continue;
  #else  /* APR_HAS_USER */
              char *group = NULL;
              apr_finfo_t finfo;
  
              if ((required_owner & ~6) && conf->authoritative) {
                  break;
              }
  
              required_owner |= 2; /* remember the requirement */
  
              if (!r->filename) {
                  reason = "no filename available";
                  continue;
              }
  
              status = apr_stat(&finfo, r->filename, APR_FINFO_GROUP, r->pool);
              if (status != APR_SUCCESS) {
                  reason = apr_pstrcat(r->pool, "could not stat file ",
                                       r->filename, NULL);
                  continue;
              }
  
              if (!(finfo.valid & APR_FINFO_GROUP)) {
                  reason = "no file group information available";
                  continue;
              }
  
              status = apr_gid_name_get(&group, finfo.group, r->pool);
              if (status != APR_SUCCESS || !group) {
                  reason = "could not get name of file group";
                  continue;
              }
  
              /* store group name in a note and let others decide... */
              apr_table_setn(r->notes, AUTHZ_GROUP_NOTE, group);
              required_owner |= 4;
              continue;
  #endif /* APR_HAS_USER */
          }
      }
  
      if (!required_owner || !conf->authoritative) {
          return DECLINED;
      }
      
      /* allow file-group passed to group db modules either if this is the
       * only applicable requirement here or if a file-owner failed but we're
       * not authoritative.
       * This allows configurations like:
       *
       * AuthzOwnerAuthoritative Off
       * require file-owner
       * require file-group
       *
       * with the semantical meaning of "either owner or group must match"
       * (inclusive or)
       *
       * [ 6 == 2 | 4; 7 == 1 | 2 | 4 ] should I use #defines instead?
       */
      if (required_owner == 6 || (required_owner == 7 && !conf->authoritative)) {
          return DECLINED;
      }
  
      ap_log_rerror(APLOG_MARK, APLOG_ERR, status, r,
                    "Authorization of user %s to access %s failed, reason: %s",
                    r->user, r->uri, reason ? reason : "unknown");
  
      ap_note_auth_failure(r);
      return HTTP_UNAUTHORIZED;
  }
  
  static void register_hooks(apr_pool_t *p)
  {
      ap_hook_auth_checker(check_file_owner, NULL, NULL, APR_HOOK_MIDDLE);
  }
  
  module AP_MODULE_DECLARE_DATA authz_owner_module =
  {
      STANDARD20_MODULE_STUFF,
      create_authz_owner_dir_config, /* dir config creater */
      NULL,                          /* dir merger --- default is to override */
      NULL,                          /* server config */
      NULL,                          /* merge server config */
      authz_owner_cmds,              /* command apr_table_t */
      register_hooks                 /* register hooks */
  };