Virtual Host Security

Table of Contents

Hotlink Protection

Enable Hotlink Protection | Suffix | Redirect URL | Allow Direct Access | Only Self Reference | Allowed Domains | REGEX Matched Domains

Access Control

Allowed List | Denied List

Authorization Realms

Realm Name | DB Type | User DB Location | Password Attribute | Member-of Attribute | User DB Max Cache Size | User DB Cache Timeout (secs) | Group DB Location | Group Member Attribute | Group DB Max Cache Size | Group DB Cache Timeout (secs) | LDAP Bind DN | LDAP Bind Password

Description

Hotlinks are requests made from an external website to files on your own website often referred to as "leeching". This practice introduces additional bandwidth usage that you should not be responsible for.

LiteSpeed web server can prevent others from hotlinking to content on your web site by checking the Referer header within an HTTP request. If the Referer header does not match your website, the request will be denied.

Enable Hotlink Protection

Description

Specifies whether to activate hotlink protection.

Syntax

Select from radio box

Suffix

Description

Specifies what kinds of files will be protected from hotlinking by listing file suffixes.

Syntax

Comma delimited list. "." is prohibited

Redirect URL

Description

Specifies a URL that a user will be redirected to when a hotlinking action is detected. You can redirect users to an image or page saying hotlinking is not allowed. If it is not specified, 403 Forbidden will be returned.

Syntax

Absolute URL

Allow Direct Access

Description

Specifies whether to allow direct access without a referer. A referer header identifies the webpage that linked to the current page. There is no "referer" header in HTTP requests when a user types in an address directly in the address box or uses a feature like "save target link as".

Syntax

Select from radio box

Only Self Reference

Description

Specifies whether to only allow references from the current web site itself. When set to Yes, Allowed Domains has no effect and no other web site can link to protected files. This can be convenient if you wish to park multiple domain names on the current web site.

Syntax

Select from radio box

Allowed Domains

Description

Specifies which web sites can link to protected content.

Syntax

Comma delimited list of domain names.

REGEX Matched Domains

Description

Specifies web sites that can link to protected content in regular expressions. The regular expression will match the domain name only and not the full URL.

Syntax

Regular expressions

Example

^.*\.mydomain\.com$

Access Control

Description

Specifies what sub networks and/or IP addresses can access the server. At the server level, this setting will affect all virtual hosts. You can also set up access control unique to each virtual host at the virtual host level. Virtual host level settings will NOT override server level settings.

Blocking/Allowing an IP is determined by the combination of the allowed list and the denied list. If you want to block only certain IPs or sub-networks, put * or ALL in the Allowed List and list the blocked IPs or sub-networks in the Denied List. If you want to allow only certain IPs or sub-networks, put * or ALL in the Denied List and list the allowed IPs or sub-networks in the Allowed List. The setting of the smallest scope that fits for an IP will be used to determine access.

Server Level: Trusted IPs or sub-networks must be specified in the Allowed List by adding a trailing "T". Trusted IPs or sub-networks are not affected by connection/throttling limits. Only server level access control can set up trusted IPs/sub-networks.

Tips

Use this at the server level for general restrictions that apply to all virtual hosts.

Allowed List

Description

Specifies the list of IPs or sub-networks allowed. * or ALL are accepted.

Syntax

Comma delimited list of IP addresses or sub-networks. A trailing "T" can be used to indicate a trusted IP or sub-network, such as 192.168.1.*T.

Example

Sub-networks: 192.168.1.0/255.255.255.0, 192.168.1.0/24, 192.168.1, or 192.168.1.*
IPv6 addresses: ::1 or [::1]
IPv6 subnets: 3ffe:302:11:2:20f:1fff:fe29:717c/64 or [3ffe:302:11:2:20f:1fff:fe29:717c]/64

Tips

Trusted IPs or sub-networks set at the server level access control will be excluded from connection/throttling limits.

Denied List

Description

Specifies the list of IPs or sub-networks disallowed.

Syntax

Comma delimited list of IP addresses or sub-networks. * or ALL are accepted.

Example

Sub-networks: 192.168.1.0/255.255.255.0, 192.168.1.0/24, 192.168.1, or 192.168.1.*
IPv6 addresses: ::1 or [::1]
IPv6 subnets: 3ffe:302:11:2:20f:1fff:fe29:717c/64 or [3ffe:302:11:2:20f:1fff:fe29:717c]/64

Authorization Realms

Description

Lists all authorization realms for this virtual host. Authorization realms are used to block unauthorized users from accessing protected web pages. A realm is a user directory containing usernames and passwords with optional group classifications. Authorization is performed at the context level. Because different contexts can share the same realm (user database), realms are defined separately from the contexts that use them. You can refer to a realm by these names in a contexts configuration.

Realm Name

Description

Specifies a unique name for the authorization realm.

DB Type

Description

Specifies how user/group data is stored for an authorization realm. Currently, user/group data can be stored in flat files or on a LDAP server.

Syntax

Select from drop down list

User DB Location

Description

Specifies the location of the user database. For DB type Password File, it is the path to the flat file containing user/password definitions. You can edit this file through the WebAdmin console by clicking on the filename.

Each line of the user file contains a username followed by a colon, followed by a crypt() encrypted password, optionally followed by a colon and group names that user belongs to. Group names are delimitated by commas. If group information is specified in the user database, then the group database will not be checked.

Example:

john:HZ.U8kgjnMOHo:admin,user


For DB type LDAP, it is the LDAP URL to query for the user information. For each valid user, the authentication data stored in the LDAP server should contain at least the user id and user password. One and only one record should be returned in the LDAP search request based on the this URL and username received in the HTTP Authentication header. "$k" must be specified in the filter part of the URL and it will be replaced with the username. The user password attribute must be returned in the query result. The attribute name of the user password is specified by Password Attribute. Group information can be optionally specified by the Member-of Attribute.

Example: At minimum, a user can be defined in LDAP with object classes: uidObject, simpleSecurityObject and organizationalRole. The following URL could be used:

ldap://localhost/ou=UserDB,dc=example,dc=com???(&(objectClass=*)(uid=$k))

Syntax

Path to user DB file or LDAP URL (RFC 2255).

Tips

It is recommended to store user password files outside of the document tree. If a user password file has to be placed inside document tree, simply name it with a leading ".ht" like .htuser to prevent it being served as a static file. LiteSpeed Web Server does not serve files prefixed with ".ht".

See Also

Group DB Location, Password Attribute, Member-of Attribute

Password Attribute

Description

Specifies the name of the password attribute for a user record stored in an LDAP server. The default value is userPassword.

Syntax

string

Member-of Attribute

Description

Specifies the name of the "Member-of" attribute for a user record stored in an LDAP server. The default value is memberOf. The "Member-of" attribute can be used to specify the group name that the user belongs to.

Syntax

string

User DB Max Cache Size

Description

Specifies the maximum cache size of the user database. Recently accessed user authentication data will be cached in memory to provide maximum performance.

Syntax

Integer number

Tips

As a larger cache will consume more memory, a higher value may or may not provide better performance. Set it to an appropriate size according to your user database size and site usage.

User DB Cache Timeout (secs)

Description

Specifies how often the backend user database will be checked for changes. Every entry in the cache has a timestamp. When cached data is older than the specified timeout, the backend database will be checked for changes. If there is no change, the timestamp will be reset to the current time, otherwise the new data will be loaded. Sevrer reload and graceful restart will clear the cache immediately.

Syntax

Integer number

Tips

If the backend database does not change very often, set a longer timeout for better performance.

Group DB Location

Description

Specifies the location of the group database.
Group information can be set either in the user database or in this standalone group DB. For user authentication, the user DB will be checked first. If the user DB also contains group information, then the group DB will not be checked.

For the DB type Password File, the group DB location should be the path to the flat file containing group definitions. You can edit this file through the WebAdmin console by clicking on the filename.

Each line of a group file should contain a groupname followed by a colon, followed by space delimited group of usernames. Example:

testgroup: user1 user2 user3

For the DB type LDAP, the group DB location should be the LDAP URL to query for group information. For each valid group, one and only one record should be returned in the LDAP search request based on this URL and the group name specified in Require (Authorized Users/Groups). "$k" must be specified in the filter part of the URL and it will be replaced with the group name. The name of the attribute that specifies members in this group is specified by the Group Member Attribute.

Example: If objectClass posixGroup is being used to store group information. The following URL could be used:
ldap://localhost/ou=GroupDB,dc=example,dc=com???(&(objectClass=*)(cn=$k))

Syntax

Filename which can be an absolute path or a relative path to $SERVER_ROOT, $VH_ROOT.

Tips

It is recommended to store a group file outside the document tree. If it has to be placed inside document tree, simply name it with a leading ".ht" like .htgroup, to prevent the file being served as a static file. LiteSpeed Web Server does not serve files prefixed with ".ht".

See Also

User DB Location, Context Require (Authorized Users/Groups), Group Member Attribute

Group Member Attribute

Description

Specifies the name of the "Member" attribute for a group record stored in an LDAP server. The default value is memberUid.

Syntax

string

Group DB Max Cache Size

Description

Specifies the maximum cache size of the group database.

Syntax

Integer number

Tips

As a larger cache will consume more memory, a higher value may or may not provide better performance. Set it to an appropriate size according to your user database size and site usage.

See Also

User DB Max Cache Size

LDAP Bind DN

Description

Specifies a DN used to bind to the server. If the LDAP server requires authentication, a bind DN and password must be specified. If not specified, anonymous bind will be used.

Syntax

string

See Also

LDAP Bind Password

LDAP Bind Password

Description

Specifies a password used to bind to the server. If the LDAP Server requires authentication, a bind DN and password must be specified.

Syntax

string

See Also

LDAP Bind DN