8. Event Handler

Added in version 2.12.

What is the difference between Policies and event handlers?

Policies are used to define the behaviour of the system. With policies you can change the way the system reacts.

With event handlers you do not change the way the system reacts. But on certain events you can trigger a new action in addition to the behaviour defined in the policies.

These additional actions are also logged to the audit log. These actions are marked as EVENT in the audit log and you can see, which event triggered these actions. Thus a single API call can cause several audit log entries: One for the API call and more for the triggered actions.

8.1. Events

Each API call is an event and you can bind arbitrary actions to each event as you like.

Internally events are marked by a decorator “event” with an event identifier. At the moment not all events might be tagged. Please drop us a note to tag all further API calls.

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An action is bound to the event token_init.

8.2. Pre and Post Handling

Added in Version 2.23.

With most event handlers you can decide if you want the action to be taken before the actual event or after the actual event. I.e. if all conditions would trigger certain actions the action is either triggered before (pre) the API request is processed or after (post) the request is processed.

Up to version 2.22 all actions where triggered after the request. In this case additional information from the response is available. E.g. if a user successfully authenticated the event will know the serial number of the token, which the user used to authenticate.

If the action is triggered before the API request is processed, the event can not know if the authentication request will be successful or which serial number a token would have. However, triggering the action before the API request is processed can have some interesting other advantages:

8.2.1. Example for Pre Handling

The administrator can define an event definition that would trigger on the event validate/check in case the the authenticating user does not have any token assigned.

The pre event definition could call the Tokenhandler with the enroll action and enroll an email token with dynamic_email for this very user.

When the API request validate/check is now processed, the user actually now has an email token and can authenticate via challenge response with this very email token without an administrator ever enrolling or assigning a token for this user.

8.3. Handler Modules and Actions

The actions are defined in handler modules. So you bind a handler module and the action, defined in the handler module, to the events.

The handler module can define several actions and each action in the handler module can require additional options.

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The event sendmail requires the option emailconfig.

8.4. Conditions

Added in version 2.14

An event handler module may also contain conditions. Only if all conditions are fulfilled, the action is triggered. Conditions are defined in the class property conditions and checked in the method check_condition. The base class for event handlers currently defines those conditions. So all event handlers come with the same conditions.

Note

In contrast to other conditions, the condition checking for tokenrealms, tokenresolvers, serial and user_token_number also evaluates to true, if this information can not be checked. I.e. if a request does not contain a serial or if the serial can not be determined, this condition will be evaluated as fulfilled.

Event Handlers are a mighty and complex tool to tweak the functioning of your privacyIDEA system. We recommend to test your definitions thoroughly to assure your expected outcome.

8.4.1. Basic conditions

The basic event handler module has the following conditions.

client_ip

The action is triggered if the client IP matches this value. The value can be a comma-separated list of single addresses or networks. To exclude entries, put a minus sign:

192.168.0.0/24,-192.168.0.12,10.0.0.2

count_auth

This can be ‘>100’, ‘<99’, or ‘=100’, to trigger the action, if the tokeninfo field ‘count_auth’ is bigger than 100, less than 99 or exactly 100.

count_auth_fail

This can be ‘>100’, ‘<99’, or ‘=100’, to trigger the action, if the difference between the tokeninfo field ‘count_auth’ and ‘count_auth_success is bigger than 100, less than 99 or exactly 100.

count_auth_success

This can be ‘>100’, ‘<99’, or ‘=100’, to trigger the action, if the tokeninfo field ‘count_auth_success’ is bigger than 100, less than 99 or exactly 100.

failcounter

This is the failcount of the token. It is increased on failed authentication attempts. If it reaches max_failcount increasing will stop and the token is locked. See Reset Fail Counter.

The condition can be set to ‘>9’, ‘=10’, or ‘<5’ and it will trigger the action accordingly.

detail_error_message

This condition checks a regular expression against the detail section in the API response. The field detail->error->message is evaluated.

Error messages can be manyfold. In case of authentication you could get error messages like:

“The user can not be found in any resolver in this realm!”

With token/init you could get:

“missing Authorization header”

Note

The field detail->error->message is only available in case of an internal error, i.e. if the response status is ``False.

detail_message

This condition checks a regular expression against the detail section in the API response. The field detail->message is evaluated.

Those messages can be manyfold like:

“wrong otp pin”

“wrong otp value”

“Only 2 failed authentications per 1:00:00”

Note

The field detail->message is available in case of status True, like an authentication request that was handled successfully but failed.

detail_message

Here you can enter a regular expression. The condition only applies if the regular expression matches the detail->message in the response.

last_auth

This condition checks if the last authentication is older than the specified time delta. The timedelta is specified with “h” (hours), “d” (days) or “y” (years). Specifying 180d would mean, that the action is triggered if the last successful authentication with the token was performed more than 180 days ago.

This can be used to send notifications to users or administrators to inform them, that there is a token, that might be orphaned.

logged_in_user

This condition checks if the logged in user is either an administrator or a normal user. This way the administrator can bind actions to events triggered by normal users or e.g. by help desk users. If a help desk user enrolls a token for a user, the user might get notified.

If a normal user enrolls some kind of token, the administrator might get notified.

otp_counter

The action is triggered, if the otp counter of a token has reached the given value. The value can either be an exact match or greater (‘>100’) or less (‘<200’) then a specified limit.

The administrator can use this condition to e.g. automatically enroll a new paper token for the user or notify the user that nearly all OTP values of a paper token have been spent.

realm

The condition realm matches the user realm. The action will only trigger, if the user in this event is located in the given realm.

This way the administrator can bind certain actions to specific realms. E.g. some actions will only be triggered, if the event happens for normal users, but not for users in admin- or helpdesk realms.

resolver

The resolver of the user, for which this event should apply.

result_status

The result.status within the response is True or False.

result_value

This condition checks the result of an event.

E.g. the result of the event validate_check can be a failed authentication. This can be the trigger to notify either the token owner or the administrator.

rollout_state

This is the rollout_state of a token. A token can be rolled out in several steps like the 2step HOTP/TOTP token. In this case the attribute “rollout_state” of the token contains certain values like ‘clientwait’ or ‘enrolled’. This way actions can be triggered, depending on the step during an enrollment process.

serial

The action will only be triggered, if the serial number of the token in the event does match the regular expression.

This is a good idea to combine with other conditions. E.g. only tokens with a certain kind of serial number like Google Authenticator will be deleted automatically.

token_has_owner

The action is only triggered, if the token is or is not assigned to a user.

token_is_orphaned

The action is only triggered, if the user, to whom the token is assigned, does not exist anymore.

token_locked

The action is only triggered, if the token in the event is locked, i.e. the maximum failcounter is reached. In such a case the user can not use the token to authenticate anymore. So an action to notify the user or enroll a new token can be triggered.

token_validity_period

Checks if the token is in the current validity period or not. Can be set to True or False.

Note

token_validity_period==False will trigger an action if either the validity period is either over or has not started, yet.

tokeninfo

The tokeninfo condition can compare any arbitrary tokeninfo field against a fixed value. You can compare strings and integers. Integers are converted automatically. Valid compares are:

myValue == 1000 myValue > 1000 myValue < 99 myTokenInfoField == EnrollmentState myTokenInfoField < ABC myTokenInfoField > abc

“myValue” and “myTokenInfoField” being any possible tokeninfo fields.

Starting with version 2.20 you can also compare dates in the isoformat like that:

myValue > 2017-10-12T10:00+0200 myValue < 2020-01-01T00:00+0000

In addition you can also use the tag {now} to compare to the curren time and you can add offsets to {now} in seconds, minutes, hours or days:

myValue < {now} myValue > {now}+10d myValue < {now}-5h

Which would match if the tokeninfo myValue is a date, which is later than 10 days from now or it the tokeninfo myValue is a date, which is 5 more than 5 hours in the past.

tokenrealm

In contrast to the realm this is the realm of the token - the tokenrealm. The action is only triggered, if the token within the event has the given tokenrealm. This can be used in workflows, when e.g. hardware tokens which are not assigned to a user are pushed into a kind of storage realm.

tokenresolver

The resolver of the token, for which this event should apply.

tokentype

The action is only triggered if the token in this event is of the given type. This way the administrator can design workflows for enrolling and re-enrolling tokens. E.g. the tokentype can be a registration token and the registration code can be easily and automatically sent to the user.

user_token_number

The action is only triggered, if the user in the event has the given number of tokens assigned.

This can be used to e.g. automatically enroll a token for the user if the user has no tokens left (token_number == 0) of to notify the administrator if the user has to many tokens assigned.

counter

The counter condition can compare the value of any arbitrary event counter against a fixed value. Valid compares are:

myCounter == 1000 myCounter > 1000 myCounter < 1000

“myCounter” being any event counter set with the Counter Handler Module.

Note

A non-existing counter value will compare as 0 (zero).

8.5. Managing Events

Using the command pi-manage events you can list, delete, enable and disable events. You can also export the complete event definitions to a file or import the event definitions from a file again. During import you can specify if you want to remove all existing events or if you want to add the events from the file to the existing events in the database.

Note

Events are identified by an id! Due to database restrictions the id is ignored during import. So importing an event with the same name will create a second event with the same name but another id.

8.6. Available Handler Modules