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Limiting directives

The Limit directive is a sectioning directive used to specify limits on access in the directory. It is legal in the global ACF and in directory ACFs (if permitted by the AllowOverride global ACF directive), and applies to the HTTP methods listed in the directive. The directives listed below are only allowed within Limit sections in an ACF.

The Deny directive specifies that access from the named hosts is to be denied. The syntax is:

    Deny from host [host ...]

The Allow directive specifies that access from the named hosts is to be permitted. The syntax is:

    Allow from host [host ...]

The NCSA server places Allow and Deny directives onto separate lists as it parses ACFs, therefore it cannot later evaluate them in the order in which they were entered. The Order directive indicates the order in which the lists of Allow and Deny directives should be evaluated. The syntax of the Order directive is:

    Order { deny,allow  | allow,deny  | mutual-failure }

Later directives override earlier directives and the default is deny,allow. mutual-failure means that any host not explicitly allowed will automatically be denied access.

The Require directive specifies which users are to be allowed access, after authentication. The syntax is:

    Require { { user  | group } name ...  | valid-user }

The argument can be a list of user names if user is specified, a list of groups of users if group is specified, or any user found in the password file if valid-user is specified.

The following directives in the global ACF will only allow the user tbl at sites in the w3.org domain to access files in the /WWW/docs/draft directory:

  <Directory /WWW/docs/draft>
      AllowOverride None
      <Limit GET>
          Deny from *
          Allow from *.w3.org
          Order allow,deny
          Require user tbl
      <Limit>
  </Directory>

The Allow directive is evaluated before the Deny directive, even though Deny appears first in the file.

Spinning the Web by Andrew Ford
© 1995 International Thomson Publishing
© 2002 Andrew Ford and Ford & Mason Ltd
Note: this HTML document was generated in December 1994 directly from the LaTeX source files using LaTeX2HTML. It was formatted into our standard page layout using the Template Toolkit. The document is mainly of historical interest as obviously many of the sites mentioned have long since disappeared.