Apache HTTP Server Version 2.2
Apache HTTP Server Version 2.2
| Description: | Authorization based on file ownership |
|---|---|
| Status: | Extension |
| Module�Identifier: | authz_owner_module |
| Source�File: | mod_authz_owner.c |
| Compatibility: | Available in Apache 2.1 and later |
This module authorizes access to files by comparing the userid used
for HTTP authentication (the web userid) with the file-system owner or
group of the requested file. The supplied username and password
must be already properly verified by an authentication module,
such as mod_auth_basic or
mod_auth_digest. mod_authz_owner
recognizes two arguments for the Require directive, file-owner and
file-group, as follows:
file-ownerjones, then the
username used to access it through the web must be jones
as well.file-groupmod_authz_groupfile or mod_authz_dbm,
and the web-username must be a member of that group. For example, if
the operating system says the requested file is owned by (system)
group accounts, the group accounts must
appear in the group database and the web-username used in the request
must be a member of that group.If mod_authz_owner is used in order to authorize
a resource that is not actually present in the filesystem
(i.e. a virtual resource), it will deny the access.
Particularly it will never authorize content negotiated "MultiViews" resources.
Consider a multi-user system running the Apache Web server, with
each user having his or her own files in ~/public_html/private. Assuming that there is a single
AuthDBMUserFile database
that lists all of their web-usernames, and that these usernames match
the system's usernames that actually own the files on the server, then
the following stanza would allow only the user himself access to his
own files. User jones would not be allowed to access
files in /home/smith/public_html/private unless they
were owned by jones instead of smith.
<Directory /home/*/public_html/private>
AuthType Basic
AuthName MyPrivateFiles
AuthBasicProvider dbm
AuthDBMUserFile /usr/local/apache2/etc/.htdbm-all
Satisfy All
Require file-owner
</Directory>
Consider a system similar to the one described above, but with
some users that share their project files in
~/public_html/project-foo. The files are owned by the
system group foo and there is a single AuthDBMGroupFile database that
contains all of the web-usernames and their group membership,
i.e. they must be at least member of a group named
foo. So if jones and smith
are both member of the group foo, then both will be
authorized to access the project-foo directories of
each other.
<Directory /home/*/public_html/project-foo>
AuthType Basic
AuthName "Project Foo Files"
AuthBasicProvider dbm
# combined user/group database
AuthDBMUserFile /usr/local/apache2/etc/.htdbm-all
AuthDBMGroupFile /usr/local/apache2/etc/.htdbm-all
Satisfy All
Require file-group
</Directory>
| Description: | Sets whether authorization will be passed on to lower level modules |
|---|---|
| Syntax: | AuthzOwnerAuthoritative On|Off |
| Default: | AuthzOwnerAuthoritative On |
| Context: | directory, .htaccess |
| Override: | AuthConfig |
| Status: | Extension |
| Module: | mod_authz_owner |
Setting the AuthzOwnerAuthoritative
directive explicitly to Off allows for
user authorization to be passed on to lower level modules (as defined
in the modules.c files) if:
file-owner the file-system owner does not
match the supplied web-username or could not be determined, orfile-group the file-system group does not
contain the supplied web-username or could not be determined.Note that setting the value to Off also allows the
combination of file-owner and file-group, so
access will be allowed if either one or the other (or both) match.
By default, control is not passed on and an authorization failure
will result in an "Authentication Required" reply. Not
setting it to Off thus keeps the system secure and forces
an NCSA compliant behaviour.