Virtual Host Security
 
Table of Contents
File Access Control Follow Symbolic Link   Enable Script   Restrained   
Per Client Throttling Control Static Requests/Second   Dynamic Requests/Second   Outbound Bandwidth   Inbound Bandwidth   
External Application Resource Control ExtApp Set UID Mode   ExtApp Chroot Mode   ExtApp Chroot Path   
Hotlink Control 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   Group DB Location   Group Member Attribute   Group DB Max Cache Size   Group DB Cache Timeout   LDAP Bind DN   LDAP Bind Password   
Request Filter Enable Request Filtering   Debug Log Level   Default Action   Scan Request Body   Disable .htaccess Override   Enable Security Audit Log   Security Audit Log   
Request Filtering Rule Set Name   Rule Set Action   Enabled   Rules Definition   
 
Follow Symbolic LinkGo to top
Description: Specifies whether to follow symbolic links in this virtual host. IF OWNER MATCH option will follow a symbolic link only if it has the same ownership. This setting overrides the default server level setting.
Syntax: Select from drop down list
Tips: [Performance & security] For better security, disable this feature. For better performance, enable it.
Enable ScriptGo to top
Description: Specifies whether scripting (non-static pages) is allowed in this virtual host. If disabled, CGI, FastCGI, LSAPI, Servlet and other scripting language are not allowed in this virtual host. Therefore if you want to use script handler, you need to enable it here as well.
Syntax: Select from radio box
RestrainedGo to top
Description: Specifies whether files beyond this virtual host root($VH_ROOT) can be accessed though this web site. If set to Yes, only files under $VH_ROOT can be accessed. And access to symbolic link or context pointing to files or directories beyond $VH_ROOT will be denied. However, it does not limit the accessibility of CGI scripts. This is useful in shared hosting environment. Follow Symbolic Link can be set to Yes to allow users using symbolic links under $VH_ROOT, but not anything beyond $VH_ROOT with this option turned on.
Syntax: Select from radio box
Tips: [Security] Turn it on in shared hosting environment.
Static Requests/SecondGo to top
Description: Specifies the maximum number of requests to static content coming from a single IP address can be processed in each second regardless of number of connections established. When the limit is reached, all future requests are tar-pitted until the next second. Request limit for dynamically generated content is independent of this limit. Per client request limit can be set at server or virtual host level where virtual host level setting overrides server level setting.
Syntax: Integer number
Tips: [Security] Trusted IP or sub-network is not effected.
See Also: Dynamic Requests/Second
Dynamic Requests/SecondGo to top
Description: Specifies the maximum number of requests to dynamically generated content coming from a single IP address can be processed in each second regardless of number of connections established. When the limit is reached, all future requests to dynamic content are tar-pitted until next second. Request limit for static content is independent of this limit. Per client request limit can be set at server or virtual host level where virtual host level setting overrides server level setting.
Syntax: Integer number
Tips: [Security] Trusted IP or sub-network is not effected
See Also: Static Requests/Second
Outbound BandwidthGo to top
Description: Specifies the maximum allowed outgoing throughput to a single IP address regardless of number of connections established. The real bandwidth could be slightly higher than this setting for efficiency. Bandwidth is allocated in 4KB units. Set to 0 to disable throttling. Per client bandwidth limit (bytes/sec) can be set at server or virtual host level where virtual host level setting overrides server level setting.
Syntax: Integer number
Tips: [Performance] Set the bandwidth in 8KB units for better performance.
  [Security] Trusted IP or sub-network is not effected.
See Also: Inbound Bandwidth
Inbound BandwidthGo to top
Description: Specifies the maximum allowed incoming throughput from a single IP address regardless of number of connections established. The real bandwidth could be slightly higher than this setting for efficiency. Bandwidth is allocated in 1KB units. Set to 0 to disable throttling. Per client bandwidth limit (bytes/sec) can be set at server or virtual host level where virtual host level setting overrides server level setting.
Syntax: Integer number
Tips: [Security] Trusted IP or sub-network is not effected.
See Also: Outbound Bandwidth
ExtApp Set UID ModeGo to top
Description: Specifies how user id is set for an external application process. Three choices are available:
  • Server UID, set user/group id of external application process same as server's user/group id;
  • CGI File UID, set user/group id of external CGI process based on the user/group id of the executable, this option only applies to CGI, not FastCGI or LSPHP;
  • Doc Root UID, set user/group id of external application process based on the user/group id of the document root of current virtual host.
Syntax: Select from drop down list
Tips: [Security] In shared hosting environment, it is recommended to use CGI File UID or Doc Root UID mode to prevent files owned by one virtual host from being accessed by external application script of another virtual host.
ExtApp Chroot ModeGo to top
Description: [Enterprise Edition Only] Specifies how the root directory is set for an external application process. In order to protect confidential system data file from being accessed by a vulnerable external application script, an alternative root path can be set for the external application process and files beyond the new root directory become inaccessible. It is generally referred to as a "chroot jail".
Three choices are available:
  • Same as Server: external application process is in the same jail as specified in the server level.
  • Virtual host root: set chroot jail to the root directory of the virtual host and external application script can only access files inside the virtual host root;
  • Customized chroot path: chroot path is specified by ExtApp Chroot Path below.
Syntax: Select from drop down list
Tips: If used properly, chroot will greatly enhance the security of external application scripts. Make sure the external application script is functional in the limited chroot jail environment.
ExtApp Chroot PathGo to top
Description: [Enterprise Edition Only] Specifies a new root directory for external application scripts of current virtual host when ExtApp Chroot Mode is set to Customized chroot path.
Syntax: Absolute path.
Hotlink ControlGo to top
Description: Hotlinking are requests made from an external website to files on your own website often referred to as "leeching". This practice introduce additional bandwidth usage that you should not be responsible for.
LiteSpeed server can prevent others from hotlinking content on your web site by checking the "Referer" header within a HTTP request. If the "Referer" header does not match your own website, the request is denied.
Enable Hotlink ProtectionGo to top
Description: Specifies whether to activate hotlink protection.
Syntax: Select from radio box
SuffixGo to top
Description: Specifies what kind of file will be protected from hotlinking by listing file suffixes here.
Syntax: comma delimited list, "." is prohibited
Redirect URLGo to top
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 AccessGo to top
Description: Specifies whether to allow direct access without a referrer. There is no "Referer" header in HTTP request 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 ReferenceGo to top
Description: Specifies whether to only allow reference from current web site itself. When set to Yes, Allowed Domains has no effect and no other web site can link to protected files. It is convenient if multiple domain names are parked on current web site.
Syntax: Select from radio box
Allowed DomainsGo to top
Description: Specifies which web site can link to protected content.
Syntax: comma delimited list of domain name
REGEX Matched DomainsGo to top
Description: Specifies web sites that can link to protected content in regular expression. The regular expression will match the domain name only and not the full URL.
Syntax: Regular expression
Access ControlGo to top
Description: Specifies what sub-network and/or IP address can access this virtual host in addition to server level access control. Virtual host setting does NOT override the server setting. Whether to block/allow an IP is determined by the combination of allowed list and denied list. If you want to block certain IP or sub-network, put * or ALL in the allowed list and list the blocked IP or sub-network in the denied list. If you want to only allow certain IP or sub-network, put * or ALL in the denied list and list the allowed IP or sub-network in the allowed list. The setting of the smallest scope that fits for an IP will be used to determine whether to block or allow access.
Allowed ListGo to top
Description: Specifies the list of IP or sub-net allowed.
Syntax: comma-delimited list of IP address or sub-network. * or ALL, sub-network can be like 192.168.1.0/255.255.255.0, 192.168.1 or 192.168.1.*.
Denied ListGo to top
Description: Specifies the list of IPs or sub-networks disallowed.
Syntax: Comma delimited list of IP address or sub-network, * or ALL, sub-network can be like 192.168.1.0/255.255.255.0, 192.168.1.0/24, 192.168.1 or 192.168.1.*.
IPv6 address should be like ::1 or [::1], IPv6 subnet should be like 3ffe:302:11:2:20f:1fff:fe29:717c/64 or [3ffe:302:11:2:20f:1fff:fe29:717c]/64.
Authorization RealmsGo to top
Description: Lists all authorization realms for this virtual host. Authorization realms is used to block unauthorized users from accessing protected web pages. A realm is a user directory containing user names and passwords with optional group classification. Authorization is performed at context level. Since different contexts can share the same realm(user database), so realms are defined separately. You can refer to a realm by its name in context configuration.
Realm NameGo to top
Description: Specifies a unique name for the authorization realm.
DB TypeGo to top
Description: Specifies how user/group data is stored for a 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 LocationGo to top
Description: Specifies the location of the user database. For DB type of Password File, it is the path to the flat file containing user/password definitions. You can edit this file through the WebAdmin by clicking on the file name.
Each line of the user file contains a username followed by a colon, followed by crypt() encrypted password optionally followed by a colon and group names that user belongs to. Group names are delimitated by comma. If group information is specified in the user DB, then the group database will not be checked.
Example:
john:HZ.U8kgjnMOHo:admin,user
For DB type of LDAP, it is the LDAP URL to query 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. User password attribute must be returned in the query result. Attribute name of user password is specified by Password Attribute. Group information can be optionally specified by 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 the user DB file or LDAP URL (RFC 2255)
Tips: [Security] It is recommended to store a user password file outside of the document tree. If it has to be placed inside document tree, simply name it with a leading ".ht" like .htuser to prevent 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 AttributeGo to top
Description: Specifies the name of the password attribute for a user record stored in LDAP server. Default value is userPassword.
Syntax: string
Member-of AttributeGo to top
Description: Specifies the name of the Member-of attribute for a user record stored in LDAP server. Default value is memberOf. Member-of attribute can be used to specify the group name that the user belongs to.
Syntax: string
User DB Max Cache SizeGo to top
Description: Specifies the maximum cache size of the user database. Most recently accessed user authentication data will be cached in memory to provide maximum performance.
Syntax: Integer number
Tips: [Performance] As 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 TimeoutGo to top
Description: Specifies how often the backend user database will be checked for changes. Every entry in the cache has a loading 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 current time, otherwise the new data will be loaded. Sever reload, graceful restart, will clear the cache immediately.
Syntax: Integer number
Tips: [Performance] If the backend database does not change very often, set a longer timeout for better performance.
Group DB LocationGo to top
Description: Specifies the location of the group database. Group information can be set either in user database or in this standalone group DB. For user authentication, user DB will be checked first, if there also contains group information, then group DB will not be checked.
For DB type of Password File, it is the path to the flat file containing group definitions. You can edit this file through the WebAdmin by clicking on the file name. Each line of the group file contains a groupname followed by a colon, then followed by space delimited group user names. Example:
testgroup: user1 user2 user3
For DB type of LDAP, it is the LDAP URL to query group information. For each valid group, one and only one record should be returned in the LDAP search request based on the this URL and group name specified in Required. "$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 member in this group is specified by 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: File name which can be absolute, or relative to $SERVER_ROOT, or relative to $VH_ROOT.
Tips: [Security] 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 being served as a static file. LiteSpeed web server does not serve files prefixed with ".ht".
See Also: User DB Location, Required, Group Member Attribute
Group Member AttributeGo to top
Description: Specifies the name of the Member attribute for a group record stored in LDAP server. Default value is memberUid.
Syntax: string
Group DB Max Cache SizeGo to top
Description: Specifies the maximum cache size of the group database. For more detail please refer to User DB Max Cache Size.
Syntax: Integer number
See Also: User DB Max Cache Size
Group DB Cache TimeoutGo to top
Description: Specifies how often the backend group database will be checked for changes. For more detail please refer to User DB Cache Timeout.
Syntax: Integer number
See Also: User DB Cache Timeout
LDAP Bind DNGo to top
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 PasswordGo to top
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
Enable Request FilteringGo to top
Description: Specifies whether to enable request content deep inspection. This feature is equvialent to Apache's mod_security, which can be used to detect and block requests with ill intention by matching known signatures.
Syntax: Select from radio box
Debug Log LevelGo to top
Description: Specifies the log level of the censoring engine debug output. Value ranges from 0 - 9, 0 will disable logging and 9 will produce the most detailed log. The log level of the server and the virtual host's error log must be set to at least INFO for this option to take effect. This is useful when testing your censoring rules.
Syntax: Integer number
See Also: Server Log Level, Virtual Host Log Level
Default ActionGo to top
Description: Specifies the default actions should be taken when a censoring rule was matched. The action string is compatible with the syntax of Apache mod_security, please refer to mod_security manual for more detail. Default value is "deny,log,satatus:403", which means to deny access with status code 403 and log the incident in the error log.
Syntax: string
Scan Request BodyGo to top
Description: Specifies whether to check the body part of a HTTP POST request. Default is No.
Syntax: Select from radio box
Disable .htaccess OverrideGo to top
Description: Specifies whether to disable .htaccess override. This is a global setting, only available at server level. Default is No.
Syntax: Select from radio box
Enable Security Audit LogGo to top
Description: Specifies whether to enable audit logging. This feature is equvialent to Apache's mod_security SecAuditEngine. If it is enabled and Security Audit Log is set, the detailed request information will be saved.
Syntax: Select from radio box
Security Audit LogGo to top
Description: Specifies the path of the security audit log, which gives more detailed information when trace back a particular user. Use Enable Security Audit Log to turn on the logging.
Syntax: File name which can be an absolute path or relative to $SERVER_ROOT.
Request Filtering Rule SetGo to top
Description: Rules configured here only work for vhosts configured in native LSWS configuration, not for vhosts from Apache httpd.conf.
NameGo to top
Description: Give a group of censorship rules a name, for display only.
Syntax: string
Rule Set ActionGo to top
Description: Specifies the actions should be taken when a censoring rule in current ruleset was matched. If not set, Default Action will be used. The action string uses the same syntax as directive SecDefaultAction in Apache mod_security, please refer to mod_security manual for more detail.
Syntax: string
EnabledGo to top
Description: Specifies whether to enable this rule set. With this option, a rule set can be quickly turned on and off without adding or removing the rule set. Default is yes.
Syntax: Select from radio box
Rules DefinitionGo to top
Description: Specifies a list of censorship rules.
Syntax of censoring rule follow Apache's mod_security directives. "SecFilter", "SecFilterSelective" and "SecRule" can be used here. You can copy and paste Security Rules in Apache configuration file.
If you are using apache config file, you have to set up rules in httpd.conf and rules defined here has no effect.
For more details about rule syntax, please refer to Mod Security document.
Syntax: string
Tips: Rules configured here only work for vhosts configured in native LSWS configuration, not for vhosts from Apache httpd.conf.