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+The IFM provides a simple authentication. Note that the permissions are always the same, so you can't have different users with different permissions out-of-the-box.
+
+To activate the authentication you have to set `auth` to 1 and set a valid value for `auth_source`.
+
+### authentication mechanisms
+Currently there are three supported authentication sources:
+* inline
+* file
+* ldap
+
+#### inline
+* syntax: `inline;<USERNAME>:<PASSWORDHASH>`
+* <PASSWORDHASH> has to be a password hash which was generated by PHPs `password_hash` function.
+
+#### file
+* syntax: `file;<PATH_TO_FILE>`
+* The file has to be readable and has to contain one line.
+* The syntax in the file is analogue to the "inline" syntax: <USERNAME>:<PASSWORDHASH>
+
+#### ldap
+* syntax: `ldap;<SERVER>;<ROOTDN>`
+* <SERVER> has to be the ip or name of the server. You can optional specify the port separated with a colon.
+* <ROOTDN> specifies the rootdn. The IFM prepends "uid=" and the entered username.
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