mod_authz_host - Apache HTTP Server Version 2.4









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Apache HTTP Server Version 2.4



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Apache Module mod_authz_host

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Description:Group authorizations based on host (name or IP
address)
Status:Base
Module Identifier:authz_host_module
Source File:mod_authz_host.c
Compatibility:The forward-dns provider was added in 2.4.19
Summary

    The authorization providers implemented by mod_authz_host are
    registered using the Require
    directive. The directive can be referenced within a
    <Directory>,
    <Files>,
    or <Location> section
    as well as .htaccess
     files to control access to particular parts of the server.
    Access can be controlled based on the client hostname or IP address.

    In general, access restriction directives apply to all
    access methods (GET, PUT,
    POST, etc). This is the desired behavior in most
    cases. However, it is possible to restrict some methods, while
    leaving other methods unrestricted, by enclosing the directives
    in a <Limit> section.

Topics

 The Require Directives
Directives
This module provides no
            directives.
Bugfix checklisthttpd changelogKnown issuesReport a bugSee also

Authentication, Authorization,
    and Access Control
Require
Comments


The Require Directives

    Apache's Require
    directive is used during the authorization phase to ensure that a user is allowed or
    denied access to a resource.  mod_authz_host extends the
    authorization types with ip, host,
    forward-dns and local.
    Other authorization types may also be
    used but may require that additional authorization modules be loaded.

    These authorization providers affect which hosts can
    access an area of the server. Access can be controlled by
    hostname, IP Address, or IP Address range.

    Since v2.4.8, expressions are supported
    within the host require directives.

Require ip

    The ip provider allows access to the server
    to be controlled based on the IP address of the remote client.
    When Require ip ip-address is specified,
    then the request is allowed access if the IP address matches.

    A full IP address:

    Require ip 10.1.2.3
Require ip 192.168.1.104 192.168.1.205


    An IP address of a host allowed access

    A partial IP address:

    Require ip 10.1
Require ip 10 172.20 192.168.2

    The first 1 to 3 bytes of an IP address, for subnet
    restriction.

    A network/netmask pair:

    Require ip 10.1.0.0/255.255.0.0

    A network a.b.c.d, and a netmask w.x.y.z. For more
    fine-grained subnet restriction.

    A network/nnn CIDR specification:

    Require ip 10.1.0.0/16

    Similar to the previous case, except the netmask consists of
    nnn high-order 1 bits.

    Note that the last three examples above match exactly the
    same set of hosts.

    IPv6 addresses and IPv6 subnets can be specified as shown
    below:

    Require ip 2001:db8::a00:20ff:fea7:ccea
Require ip 2001:db8:1:1::a
Require ip 2001:db8:2:1::/64
Require ip 2001:db8:3::/48


    Note: As the IP addresses are parsed on startup, expressions are
    not evaluated at request time.



Require host

    The host provider allows access to the server
    to be controlled based on the host name of the remote client.
    When Require host host-name is specified,
    then the request is allowed access if the host name matches.

    A (partial) domain-name

    Require host example.org
Require host .net example.edu


    Hosts whose names match, or end in, this string are allowed
    access. Only complete components are matched, so the above
    example will match foo.example.org but it will not
    match fooexample.org. This configuration will cause
    Apache to perform a double reverse DNS lookup on the client IP
    address, regardless of the setting of the HostnameLookups directive.  It will do
    a reverse DNS lookup on the IP address to find the associated
    hostname, and then do a forward lookup on the hostname to assure
    that it matches the original IP address.  Only if the forward
    and reverse DNS are consistent and the hostname matches will
    access be allowed.



Require forward-dns

    The forward-dns provider allows access to the server
    to be controlled based on simple host names.  When
    Require forward-dns host-name is specified,
    all IP addresses corresponding to host-name
    are allowed access.

    In contrast to the host provider, this provider does not
    rely on reverse DNS lookups: it simply queries the DNS for the host name
    and allows a client if its IP matches.  As a consequence, it will only
    work with complete host names that can be resolved in DNS, not partial domain names.  
    However, as the reverse DNS is not used, and DNS lookups occur at request processing
    time (instead of startup), it will work with clients which use a dynamic DNS service.

    Require forward-dns dynamic.example.org


    A client the IP of which is resolved from the name
    dynamic.example.org will be granted access.

    The forward-dns provider was added in 2.4.19.


Require local

    The local provider allows access to the server if any
    of the following conditions is true:

    
        the client address matches 127.0.0.0/8
        the client address is ::1
        both the client and the server address of the connection are
        the same
    

    This allows a convenient way to match connections that originate from
    the local host:

    Require local




Security Note

    If you are proxying content to your server, you need to be aware
    that the client address will be the address of your proxy server,
    not the address of the client, and so using the Require
    directive in this context may not do what you mean. See
    mod_remoteip for one possible solution to this
    problem.






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