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<H1 ALIGN="CENTER">Module mod_auth</H1>
<P>This module provides for user authentication using text files.
<P><A
HREF="module-dict.html#Status"
REL="Help"
><STRONG>Status:</STRONG></A> Base
<BR>
<A
HREF="module-dict.html#SourceFile"
REL="Help"
><STRONG>Source File:</STRONG></A> mod_auth.c
<BR>
<A
HREF="module-dict.html#ModuleIdentifier"
REL="Help"
><STRONG>Module Identifier:</STRONG></A> auth_module
</P>
<H2>Summary</H2>
<P>This module allows the use of HTTP Basic Authentication to restrict
access by looking up users in plain text password and group files.
Similar functionality and greater scalability is provided by <A
HREF="mod_auth_dbm.html">mod_auth_dbm</A> and <A
HREF="mod_auth_db.html">mod_auth_db</A>. HTTP Digest Authentication
is provided by <A HREF="mod_auth_digest.html">mod_auth_digest</A>.
<H2>Directives</H2>
<UL>
<LI><A HREF="#authgroupfile">AuthGroupFile</A>
<LI><A HREF="#authuserfile">AuthUserFile</A>
<LI><A HREF="#authauthoritative">AuthAuthoritative</A>
</UL>
<P>See also: <A HREF="core.html#require">require</A>
and <A HREF="core.html#satisfy">satisfy</A>.</P>
<HR>
<H2><A NAME="authgroupfile">AuthGroupFile</A> directive</H2>
<!--%plaintext &lt;?INDEX {\tt AuthGroupFile} directive&gt; -->
<A
HREF="directive-dict.html#Syntax"
REL="Help"
><STRONG>Syntax:</STRONG></A> AuthGroupFile <EM>file-path</EM><BR>
<A
HREF="directive-dict.html#Context"
REL="Help"
><STRONG>Context:</STRONG></A> directory, .htaccess<BR>
<A
HREF="directive-dict.html#Override"
REL="Help"
><STRONG>Override:</STRONG></A> AuthConfig<BR>
<A
HREF="directive-dict.html#Status"
REL="Help"
><STRONG>Status:</STRONG></A> Base<BR>
<A
HREF="directive-dict.html#Module"
REL="Help"
><STRONG>Module:</STRONG></A> mod_auth<P>
The AuthGroupFile directive sets the name of a textual file containing the list
of user groups for user authentication. <EM>File-path</EM> is the path
to the group file. If it is not absolute (<EM>i.e.</EM>, if it
doesn't begin with a slash), it is treated as relative to the ServerRoot.
<P>
Each line of the group file contains a groupname followed by a colon, followed
by the member usernames separated by spaces. Example:
<BLOCKQUOTE><CODE>mygroup: bob joe anne</CODE></BLOCKQUOTE>
Note that searching large text files is <EM>very</EM> inefficient;
<A HREF="mod_auth_dbm.html#authdbmgroupfile">AuthDBMGroupFile</A> should
be used instead.<P>
Security: make sure that the AuthGroupFile is stored outside the
document tree of the web-server; do <EM>not</EM> put it in the directory that
it protects. Otherwise, clients will be able to download the AuthGroupFile.<P>
See also <A HREF="core.html#authname">AuthName</A>,
<A HREF="core.html#authtype">AuthType</A> and
<A HREF="#authuserfile">AuthUserFile</A>.<P><HR>
<H2><A NAME="authuserfile">AuthUserFile</A> directive</H2>
<!--%plaintext &lt;?INDEX {\tt AuthUserFile} directive&gt; -->
<A
HREF="directive-dict.html#Syntax"
REL="Help"
><STRONG>Syntax:</STRONG></A> AuthUserFile <EM>file-path</EM><BR>
<A
HREF="directive-dict.html#Context"
REL="Help"
><STRONG>Context:</STRONG></A> directory, .htaccess<BR>
<A
HREF="directive-dict.html#Override"
REL="Help"
><STRONG>Override:</STRONG></A> AuthConfig<BR>
<A
HREF="directive-dict.html#Status"
REL="Help"
><STRONG>Status:</STRONG></A> Base<BR>
<A
HREF="directive-dict.html#Module"
REL="Help"
><STRONG>Module:</STRONG></A> mod_auth<P>
The AuthUserFile directive sets the name of a textual file containing
the list of users and passwords for user
authentication. <EM>File-path</EM> is the path to the user
file. If it is not absolute (<EM>i.e.</EM>, if it doesn't begin with a
slash), it is treated as relative to the ServerRoot.
<P> Each line of the user file file contains a username followed
by a colon, followed by the crypt() encrypted password. The behavior
of multiple occurrences of the same user is undefined.
<P>
The utility <a href="/programs/htpasswd.html">htpasswd</a> which is
installed as part of the binary distribution, or which can be found in
<code>src/support</code>, is used to maintain this password file. See
the <code>man</code> page for more details. In short
<p>
<blockquote>
<code>htpasswd -c Filename username</code><br>
Create a password file 'Filename' with 'username'
as the initial ID. It will prompt for the password.
<code>htpasswd Filename username2</code><br>
Adds or modifies in password file 'Filename' the 'username'.
</blockquote>
<P> Note that
searching large text files is <EM>very</EM> inefficient;
<A HREF="mod_auth_dbm.html#authdbmuserfile">AuthDBMUserFile</A> should be
used instead.
<P>
Security: make sure that the AuthUserFile is stored outside the
document tree of the web-server; do <EM>not</EM> put it in the directory that
it protects. Otherwise, clients will be able to download the AuthUserFile.<P>
See also <A HREF="core.html#authname">AuthName</A>,
<A HREF="core.html#authtype">AuthType</A> and
<A HREF="#authgroupfile">AuthGroupFile</A>.<P>
<HR>
<H2><A NAME="authauthoritative">AuthAuthoritative</A> directive</H2>
<!--%plaintext &lt;?INDEX {\tt AuthAuthoritative} directive&gt; -->
<A
HREF="directive-dict.html#Syntax"
REL="Help"
><STRONG>Syntax:</STRONG></A> AuthAuthoritative on|off<BR>
<A
HREF="directive-dict.html#Default"
REL="Help"
><STRONG>Default:</STRONG></A> <CODE>AuthAuthoritative on</CODE><BR>
<A
HREF="directive-dict.html#Context"
REL="Help"
><STRONG>Context:</STRONG></A> directory, .htaccess<BR>
<A
HREF="directive-dict.html#Override"
REL="Help"
><STRONG>Override:</STRONG></A> AuthConfig<BR>
<A
HREF="directive-dict.html#Status"
REL="Help"
><STRONG>Status:</STRONG></A> Base<BR>
<A
HREF="directive-dict.html#Module"
REL="Help"
><STRONG>Module:</STRONG></A> mod_auth<P>
Setting the AuthAuthoritative directive explicitly to <STRONG>'off'</STRONG>
allows for both authentication and authorization to be passed on to
lower level modules (as defined in the <CODE>Configuration</CODE> and
<CODE>modules.c</CODE> files) if there is <STRONG>no userID</STRONG> or
<STRONG>rule</STRONG> 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.
<P>
So if a userID appears in the database of more than one module; or if
a valid <CODE>Require</CODE> 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.
<P>
A common use for this is in conjunction with one of the database
modules; such as <A
HREF="mod_auth_db.html"><CODE>mod_auth_db.c</CODE></A>, <A
HREF="mod_auth_dbm.html"><CODE>mod_auth_dbm.c</CODE></A>,
<CODE>mod_auth_msql.c</CODE>, and <A
HREF="mod_auth_anon.html"><CODE>mod_auth_anon.c</CODE></A>. These modules
supply the bulk of the user credential checking; but a few
(administrator) related accesses fall through to a lower level with a
well protected AuthUserFile.
<P>
<A
HREF="directive-dict.html#Default"
REL="Help"
><STRONG>Default:</STRONG></A> 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 NCSA compliant
behaviour.
<P>
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 such as mSQL. Make
sure that the AuthUserFile is stored outside the document tree of the
web-server; do <EM>not</EM> put it in the directory that it
protects. Otherwise, clients will be able to download the
AuthUserFile.
<P>
See also <A HREF="core.html#authname">AuthName</A>,
<A HREF="core.html#authtype">AuthType</A> and
<A HREF="#authgroupfile">AuthGroupFile</A>.<P>
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