2 <!DOCTYPE modulesynopsis SYSTEM "../style/modulesynopsis.dtd">
3 <?xml-stylesheet type="text/xsl" href="../style/manual.en.xsl"?>
4 <!-- $LastChangedRevision$ -->
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10 The ASF licenses this file to You under the Apache License, Version 2.0
11 (the "License"); you may not use this file except in compliance with
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14 http://www.apache.org/licenses/LICENSE-2.0
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23 <modulesynopsis metafile="mod_authn_dbd.xml.meta">
25 <name>mod_authn_dbd</name>
26 <description>User authentication using an SQL database</description>
27 <status>Extension</status>
28 <sourcefile>mod_authn_dbd.c</sourcefile>
29 <identifier>authn_dbd_module</identifier>
30 <compatibility>Available in Apache 2.1 and later</compatibility>
33 <p>This module provides authentication front-ends such as
34 <module>mod_auth_digest</module> and <module>mod_auth_basic</module>
35 to authenticate users by looking up users in SQL tables.
36 Similar functionality is provided by, for example,
37 <module>mod_authn_file</module>.</p>
38 <p>This module relies on <module>mod_dbd</module> to specify
39 the backend database driver and connection parameters, and
40 manage the database connections.</p>
42 <p>When using <module>mod_auth_basic</module> or
43 <module>mod_auth_digest</module>, this module is invoked via the
44 <directive module="mod_auth_basic">AuthBasicProvider</directive> or
45 <directive module="mod_auth_digest">AuthDigestProvider</directive>
46 with the <code>dbd</code> value.</p>
49 <seealso><directive module="mod_authn_core">AuthName</directive></seealso>
50 <seealso><directive module="mod_authn_core">AuthType</directive></seealso>
52 <directive module="mod_auth_basic">AuthBasicProvider</directive>
55 <directive module="mod_auth_digest">AuthDigestProvider</directive>
57 <seealso><directive module="mod_dbd">DBDriver</directive></seealso>
58 <seealso><directive module="mod_dbd">DBDParams</directive></seealso>
60 <section id="example">
61 <title>Configuration Example</title>
62 <p>This simple example shows use of this module in the context of
63 the Authentication and DBD frameworks.</p>
65 # mod_dbd configuration
67 DBDParams "dbname=apacheauth user=apache password=xxxxxx"
74 <Directory /usr/www/myhost/private>
75 # mod_authn_core and mod_auth_basic configuration
81 # mod_authz_core configuration
84 # mod_authn_dbd SQL query to authenticate a user
86 "SELECT password FROM authn WHERE user = %s"
91 <section id="exposed">
92 <title>Exposing Login Information</title>
94 If httpd was built against <glossary>APR</glossary> version 1.3.0
95 or higher, then whenever a query is made to the database server, all
96 column values in the first row returned by the query are placed in the
97 environment, using environment variables with the prefix "AUTHENTICATE_".
99 <p>If a database query for example returned the username, full name
100 and telephone number of a user, a CGI program will have access to
101 this information without the need to make a second independent database
102 query to gather this additional information.</p>
103 <p>This has the potential to dramatically simplify the coding and
104 configuration required in some web applications.
109 <name>AuthDBDUserPWQuery</name>
110 <description>SQL query to look up a password for a user</description>
111 <syntax>AuthDBDUserPWQuery <var>query</var></syntax>
112 <contextlist><context>directory</context>
116 <p>The <directive>AuthDBDUserPWQuery</directive> specifies an
117 SQL query to look up a password for a specified user. The user's ID
118 will be passed as a single string parameter when the SQL query is
119 executed. It may be referenced within the query statement using
120 a <code>%s</code> format specifier.</p>
121 <example><title>Example</title><pre>
123 "SELECT password FROM authn WHERE user = %s"
125 <p>The first column value of the first row returned by the query
126 statement should be a string containing the encrypted password.
127 Subsequent rows will be ignored. If no rows are returned, the user
128 will not be authenticated through <module>mod_authn_dbd</module>.</p>
129 <p>If httpd was built against <glossary>APR</glossary> version 1.3.0
130 or higher, any additional column values in the first row returned by
131 the query statement will be stored as environment variables with
132 names of the form <code>AUTHENTICATE_<var>COLUMN</var></code>.
138 <name>AuthDBDUserRealmQuery</name>
139 <description>SQL query to look up a password hash for a user and realm.
141 <syntax>AuthDBDUserRealmQuery <var>query</var></syntax>
142 <contextlist><context>directory</context>
146 <p>The <directive>AuthDBDUserRealmQuery</directive> specifies an
147 SQL query to look up a password for a specified user and realm.
148 The user's ID and the realm, in that order, will be passed as string
149 parameters when the SQL query is executed. They may be referenced
150 within the query statement using <code>%s</code> format specifiers.</p>
151 <example><title>Example</title><pre>
152 AuthDBDUserRealmQuery \
153 "SELECT password FROM authn WHERE user = %s AND realm = %s"
155 <p>The first column value of the first row returned by the query
156 statement should be a string containing the encrypted password.
157 Subsequent rows will be ignored. If no rows are returned, the user
158 will not be authenticated through <module>mod_authn_dbd</module>.</p>
159 <p>If httpd was built against <glossary>APR</glossary> version 1.3.0
160 or higher, any additional column values in the first row returned by
161 the query statement will be stored as environment variables with
162 names of the form <code>AUTHENTICATE_<var>COLUMN</var></code>.