Adaptive Authentication - IP Intelligence

CAS provides you with the capability to examine the client IP address and decide whether access should be granted. This may be useful to detect bot, proxy or VPN traffic and protect your deployment from fraud, automated attacks, crawlers, etc.

The result of the IP address examination may either ban and request the request, allow it to go through, or present a score to indicate the probability of an IP address that may be questionable. If the result is ranked score, it will be compared against the configured risk threshold to determine whether the request may proceed.

Banned IP address can either be defined as patterns in the CAS settings, or they may be examined using the listed strategies below.

The client IP address is submitted to a REST endpoint as the header clientIpAddress under a GET request. The expected result status codes are the following:

Code	Description
`401`, `403`	IP address is banned and the request will be rejected.
`200`, `202`	IP address is allowed and the request may proceed.
All Others	Response body is expected to contain a score between `1` and `0`, (`1=Banned` and `0=Allowed`).

The following settings and properties are available from the CAS configuration catalog:

cas.authn.adaptive.ip-intel.rest.urlThe endpoint URL to contact and retrieve attributes.

no default

RequiredSpEL

The endpoint URL to contact and retrieve attributes.

Type: String
Default: none
Defined by: RestfulAdaptiveAuthenticationIPIntelligenceProperties
Supports: Spring Expression Language

cas.authn.adaptive.ip-intel.rest.basic-auth-passwordIf REST endpoint is protected via basic authentication, specify the password for authentication.

no default

If REST endpoint is protected via basic authentication, specify the password for authentication.

Type: String
Default: none
Defined by: RestfulAdaptiveAuthenticationIPIntelligenceProperties

cas.authn.adaptive.ip-intel.rest.basic-auth-usernameIf REST endpoint is protected via basic authentication, specify the username for authentication.

no default

If REST endpoint is protected via basic authentication, specify the username for authentication.

Type: String
Default: none
Defined by: RestfulAdaptiveAuthenticationIPIntelligenceProperties

cas.authn.adaptive.ip-intel.rest.headersHeaders, defined as a Map, to include in the request when making the REST call.

no default

Headers, defined as a Map, to include in the request when making the REST call. Will overwrite any header that CAS is pre-defined to send and include in the request. Key in the map should be the header name and the value in the map should be the header value.

Type: Map<String,String>
Default: none
Defined by: RestfulAdaptiveAuthenticationIPIntelligenceProperties

cas.authn.adaptive.ip-intel.rest.maximum-retry-attemptsWhen attempting to reach the endpoint, this setting controls the number of retry attempts that CAS should execute Setting this value to a zero or negative value will disable the retry policy.

3

When attempting to reach the endpoint, this setting controls the number of retry attempts that CAS should execute Setting this value to a zero or negative value will disable the retry policy.

Type: Integer
Default: 3
Defined by: RestfulAdaptiveAuthenticationIPIntelligenceProperties

cas.authn.adaptive.ip-intel.rest.methodHTTP method to use when contacting the rest endpoint.

GET

HTTP method to use when contacting the rest endpoint. Examples include GET, POST, etc.

Type: String
Default: GET
Defined by: RestfulAdaptiveAuthenticationIPIntelligenceProperties

Required settings may be needed to activate or affect the feature; review them even when they have a default. Optional settings only need to be set to change a default or to turn on the behavior they control. Third party settings belong to libraries such as Spring Boot that CAS builds on; their own documentation may have more detail.

Notes on configuration

Configuration Metadata

The collection of configuration properties listed in this section are automatically generated from the CAS source and components that contain the actual field definitions, types, descriptions, modules, etc. This metadata may not always be 100% accurate, or could be lacking details and sufficient explanations.

Be Selective

This section is meant as a guide only. Do NOT copy/paste the entire collection of settings into your CAS configuration; rather pick only the properties that you need. Do NOT enable settings unless you are certain of their purpose and do NOT copy settings into your configuration only to keep them as reference. All these ideas lead to upgrade headaches, maintenance nightmares and premature aging.

YAGNI

Note that for nearly ALL use cases, declaring and configuring properties listed here is sufficient. You should NOT have to explicitly massage a CAS XML/Java/etc configuration file to design an authentication handler, create attribute release policies, etc. CAS at runtime will auto-configure all required changes for you. If you are unsure about the meaning of a given CAS setting, do NOT turn it on without hesitation. Review the codebase or better yet, ask questions to clarify the intended behavior.

Naming Convention

Property names can be specified in very relaxed terms. For instance cas.someProperty, cas.some-property, cas.some_property are all valid names. While all forms are accepted by CAS, there are certain components (in CAS and other frameworks used) whose activation at runtime is conditional on a property value, where this property is required to have been specified in CAS configuration using kebab case. This is both true for properties that are owned by CAS as well as those that might be presented to the system via an external library or framework such as Spring Boot, etc.

Note

When possible, properties should be stored in lower-case kebab format, such as cas.property-name=value. The only possible exception to this rule is when naming actuator endpoints; The name of the actuator endpoints (i.e. ssoSessions) MUST remain in camelCase mode.

Settings and properties that are controlled by the CAS platform directly always begin with the prefix cas. All other settings are controlled and provided to CAS via other underlying frameworks and may have their own schemas and syntax. BE CAREFUL with the distinction. Unrecognized properties are rejected by CAS and/or frameworks upon which CAS depends. This means if you somehow misspell a property definition or fail to adhere to the dot-notation syntax and such, your setting is entirely refused by CAS and likely the feature it controls will never be activated in the way you intend.

Validation

Configuration properties are automatically validated on CAS startup to report issues with configuration binding, especially if defined CAS settings cannot be recognized or validated by the configuration schema. Additional validation processes are also handled via Configuration Metadata and property migrations applied automatically on startup by Spring Boot and family.

Indexed Settings

CAS settings able to accept multiple values are typically documented with an index, such as cas.some.setting[0]=value. The index [0] is meant to be incremented by the adopter to allow for distinct multiple configuration blocks.

To prepare CAS to support and integrate with Apache Groovy, please review this guide.

The client IP address may be examined using a Groovy script whose outline should match the following:

import org.apereo.cas.authentication.principal.*
import org.apereo.cas.authentication.*
import org.apereo.cas.util.*
import org.apereo.cas.authentication.adaptive.intel.*

def run(Object[] args) {
    def (requestContext,clientIpAddress,logger) = args
    
    logger.info("Client ip address provided is ${clientIpAddress}")
    
    if (ipAddressIsRejected())
        return IPAddressIntelligenceResponse.banned()
    
    return IPAddressIntelligenceResponse.allowed()
}

The following settings and properties are available from the CAS configuration catalog:

cas.authn.adaptive.ip-intel.groovy.locationThe location of the resource.

no default

Required

The location of the resource. Resources can be URLs, or files found either on the classpath or outside somewhere in the file system.

In the event the configured resource is a Groovy script, especially if the script is set to reload on changes, you may need to adjust the total number of inotify instances. On Linux, you may need to add the following line to /etc/sysctl.conf: fs.inotify.max_user_instances = 256.

You can check the current value via cat /proc/sys/fs/inotify/max_user_instances.

In situations and scenarios where CAS is able to automatically watch the underlying resource for changes and detect updates and modifications dynamically, you may be able to specify the following setting as either an environment variable or system property with a value of false to disable the resource watcher: org.apereo.cas.util.io.PathWatcherService.

Type: Resource
Default: none
Defined by: GroovyAdaptiveAuthenticationIPIntelligenceProperties

Groovy scripting

CAS takes advantage of Apache Groovy in forms of either embedded or external scripts that allow one to, by default, dynamically build constructs, attributes, access strategies and a lot more. To activate the functionality described here, you may need to prepare CAS to support and integrate with Apache Groovy.

Please review this guide to configure your build.

Notes on configuration

Configuration Metadata

Be Selective

YAGNI

Naming Convention

Note

Validation

Indexed Settings

To prepare CAS to support and integrate with Apache Groovy, please review this guide.

Please see this link for more info. A valid subscription is required for large query counts.

Usage Warning!
This is a free service, primarily useful for development, testing and demos. Production deployments of this service require a subscription that can handle the expected query count and load.

Note that a valid email that is checked frequently must be used in the contact field or else the service might be disabled without notice. Furthermore, DO NOT exceed more than 500 queries per day & 15 queries per minute. See FAQ for further information.

The following settings and properties are available from the CAS configuration catalog:
cas.authn.adaptive.ip-intel.black-dot.email-addressInclude your contact information so you can be notified if a problem arise or if there are core changes.

no default

Required

Include your contact information so you can be notified if a problem arise or if there are core changes.

Type

String

Default

none

Defined by

BlackDot
cas.authn.adaptive.ip-intel.black-dot.modeControl the mode.

DYNA_LIST
Control the mode.

DYNA_LIST: If you get a value between 0 - 1, exclusive (like 0.99, 0.99999, 0.97), these values are generated by dynamic checks which looks for characteristics of the given IP. IPs that are either manually banned or seen on a public proxy site will return a value of 1. If you only want manually banned or public proxies, then in your code just look for the value "1". However, there are many IPs that haven't gone through manual review and IPs can change behavior very frequently (which is why dynamic checks exist in the first place). If you only look for the value of "1", then expect to have more proxy / VPN / bad IPs go through your system, however, false positives are less likely if you use the dynamic ban list option. If you wish to use only manually banned and public proxy IPs, append the parameter flags=m, the system will only return a result of 0 or 1. This option is the best to start off with that will have a noticeable impact in bot / proxy / VPN traffic, especially if you don't have any data sets to test with the system.

DYNA_CHECK: In this scenario, you want to use dynamic checks as well but you want to skip additional checks to see if the IP is a bad ip (see What do you mean by "Bad IP"?). In this mode, some bad IPs are still detected but the system does not attempt to go through the full bad IPs check because the time for the extra checks vary wildly (between an extra 200ms to 2 seconds). In this mode, false positives are more likely than dynamic ban lists only. Scores are lower compared to the full IP check (without any flag options) because less attributes are considered. If you wish to use dynamic ban list and dynamic checks only, append the parameter flags=b. This option is the best if dynamic ban lists isn't catching enough IPs but you don't want to run the full check because it takes too long and/or you want to have a predictable execution time.

FULL: Let the system to do a full lookup with one query.

Type

String

Default

DYNA_LIST

Defined by

BlackDot
cas.authn.adaptive.ip-intel.black-dot.urlURL endpoint of the service to make API calls.

http://check.getipintel.net/check.php?ip=%s

URL endpoint of the service to make API calls.

Type

String

Default

http://check.getipintel.net/check.php?ip=%s

Defined by

BlackDot
Required settings may be needed to activate or affect the feature; review them even when they have a default. Optional settings only need to be set to change a default or to turn on the behavior they control. Third party settings belong to libraries such as Spring Boot that CAS builds on; their own documentation may have more detail.

Notes on configuration

Configuration Metadata

The collection of configuration properties listed in this section are automatically generated from the CAS source and components that contain the actual field definitions, types, descriptions, modules, etc. This metadata may not always be 100% accurate, or could be lacking details and sufficient explanations.

Be Selective

This section is meant as a guide only. Do NOT copy/paste the entire collection of settings into your CAS configuration; rather pick only the properties that you need. Do NOT enable settings unless you are certain of their purpose and do NOT copy settings into your configuration only to keep them as reference. All these ideas lead to upgrade headaches, maintenance nightmares and premature aging.

YAGNI

Note that for nearly ALL use cases, declaring and configuring properties listed here is sufficient. You should NOT have to explicitly massage a CAS XML/Java/etc configuration file to design an authentication handler, create attribute release policies, etc. CAS at runtime will auto-configure all required changes for you. If you are unsure about the meaning of a given CAS setting, do NOT turn it on without hesitation. Review the codebase or better yet, ask questions to clarify the intended behavior.

Naming Convention

Property names can be specified in very relaxed terms. For instance cas.someProperty, cas.some-property, cas.some_property are all valid names. While all forms are accepted by CAS, there are certain components (in CAS and other frameworks used) whose activation at runtime is conditional on a property value, where this property is required to have been specified in CAS configuration using kebab case. This is both true for properties that are owned by CAS as well as those that might be presented to the system via an external library or framework such as Spring Boot, etc.

Note
When possible, properties should be stored in lower-case kebab format, such as cas.property-name=value. The only possible exception to this rule is when naming actuator endpoints; The name of the actuator endpoints (i.e. ssoSessions) MUST remain in camelCase mode.

Settings and properties that are controlled by the CAS platform directly always begin with the prefix cas. All other settings are controlled and provided to CAS via other underlying frameworks and may have their own schemas and syntax. BE CAREFUL with the distinction. Unrecognized properties are rejected by CAS and/or frameworks upon which CAS depends. This means if you somehow misspell a property definition or fail to adhere to the dot-notation syntax and such, your setting is entirely refused by CAS and likely the feature it controls will never be activated in the way you intend.

Validation

Configuration properties are automatically validated on CAS startup to report issues with configuration binding, especially if defined CAS settings cannot be recognized or validated by the configuration schema. Additional validation processes are also handled via Configuration Metadata and property migrations applied automatically on startup by Spring Boot and family.

Indexed Settings

CAS settings able to accept multiple values are typically documented with an index, such as cas.some.setting[0]=value. The index [0] is meant to be incremented by the adopter to allow for distinct multiple configuration blocks.