mod_auth_db.c
file, and
is not compiled in by default. It provides for user authentication using
Berkeley DB files. It is an alternative to DBM
files for those systems which support DB and not DBM. It is only
available in Apache 1.1 and later.
The AuthDBGroupFile directive sets the name of a DB file containing the list of user groups for user authentication. Filename is the absolute path to the group file.
The group file is keyed on the username. The value for a user is a comma-separated list of the groups to which the users belongs. There must be no whitespace within the value, and it must never contain any colons.
Security: make sure that the AuthDBGroupFile is stored outside the document tree of the web-server; do not put it in the directory that it protects. Otherwise, clients will be able to download the AuthDBGroupFile unless otherwise protected.
Combining Group and Password DB files: In some cases it is easier to manage a single database which contains both the password and group details for each user. This simplifies any support programs that need to be written: they now only have to deal with writing to and locking a single DBM file. This can be accomplished by first setting the group and password files to point to the same DB file:
AuthDBGroupFile /www/userbase
AuthDBUserFile /www/userbase
The key for the single DB record is the username. The value consists of
Unix Crypt-ed Password : List of Groups [ : (ignored) ]
The password section contains the Unix crypt() password as before. This is
followed by a colon and the comma separated list of groups. Other data may
optionally be left in the DB file after another colon; it is ignored by the
authentication module. See also AuthName, AuthType and AuthDBUserFile.
The AuthDBUserFile directive sets the name of a DB file containing the list of users and passwords for user authentication. Filename is the absolute path to the user file.
The user file is keyed on the username. The value for a user is the crypt() encrypted password, optionally followed by a colon and arbitrary data. The colon and the data following it will be ignored by the server.
Security: make sure that the AuthDBUserFile is stored outside the document tree of the web-server; do not put it in the directory that it protects. Otherwise, clients will be able to download the AuthDBUserFile.
Important compatibility note: The implementation of "dbmopen" in the apache modules reads the string length of the hashed values from the DB data structures, rather than relying upon the string being NULL-appended. Some applications, such as the Netscape web server, rely upon the string being NULL-appended, so if you are having trouble using DB files interchangeably between applications this may be a part of the problem.
See also AuthName, AuthType and AuthDBGroupFile.
Setting the AuthDBAuthoritative directive explicitly to 'off'
allows for both authentication and authorization to be passed on
to lower level modules (as defined in the Configuration
and modules.c
file if there is no userID or
rule matching the supplied userID. If there is a userID
and/or rule specified; the usual password and access checks will
be applied and a failure will give an Authorization Required reply.
So if a userID appears in the database of more than one module; or if a valid require directive applies to more than one module; then the first module will verify the credentials; and no access is passed on; regardless of the AuthAuthoritative setting.
A common use for this is in conjunction with one of the basic auth
modules; such as mod_auth.c
.
Whereas this DB module supplies the bulk of the user credential
checking; a few (administrator) related accesses fall through to
a lower level with a well protected .htpasswd file.
Default: By default; control is not passed on; and an unknown userID or rule will result in an Authorization Required reply. Not setting it thus keeps the system secure; and forces an NSCA compliant behaviour.
Security: Do consider the implications of allowing a user to allow fall-through in his .htaccess file; and verify that this is really what you want; Generally it is easier to just secure a single .htpasswd file, than it is to secure a database which might have more access interfaces.
See also AuthName, AuthType and AuthDBGroupFile.