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# <a id="security"></a> Security

Access control is a vital part of configuring Icinga Web 2 in a secure way.
It is important that not every user that has access to Icinga Web 2 is able
to do any action or see any host and service. For example, it is useful to allow
only a small group of administrators to change the Icinga Web 2 configuration, to prevent misconfiguration or security breaches. Another important use case is the creation groups of
users that can only see the fraction of hosts and services of the monitoring
environment they are in charge of.

This chapter will describe how to do the security configuration of Icinga Web 2
and how apply permissions and restrictions to users or groups of users.

## Basics

Icinga Web 2 access control is done by defining **roles** that relate permissions or restrictions to **users** and **group**.
There are two general kinds of things to which access can be managed: actions and objects.


### Actions

Actions are all the things an Icinga Web 2 user can do, like changing a certain configuration,
changing permissions or sending a command to the Icinga instance through the <a href="http://docs.icinga.org/icinga2/latest/doc/module/icinga2/toc#!/icinga2/latest/doc/module/icinga2/chapter/getting-started#setting-up-external-command-pipe">Command Pipe</a> in the monitoring module. All actions must be be **allowed explicitly** using permissions.

A permission is a simple list of identifiers of actions a user is
allowed to do. Permissions are described in greater detail in the
section [Permissions](#permissions).

### Objects

There are all kinds of different objects in Icinga Web 2: Hosts, Services, Notifications, Downtimes and Events.

By default, a user can **see everything**, but it is possible to **explicitly restrict** what each user can see using restrictions.

Restrictions are complex filter queries that describe what objects should be displayed to a user. Restrictions are described
in greater detail in the section [Restrictions](#restrictions).

### Users

Anyone who can **login** to Icinga Web 2 is considered a user and can be referenced to by the
**user name** used during login.
For example, there might be user called **jdoe** authenticated
using Active Directory, and a user **icingaadmin** that is authenticated using a MySQL-Database as backend. Both can be referenced by using their the user names **icingaadmin** or **jdoe**, when referring to those users in the configuration.

Icinga Web 2 users and groups are not configured by a configuration file, but provided by
an **authentication backend**. For extended information on setting up authentication backends and managing users, please read the chapter [Authentication](authentication.md#authentication).


<div class="info-box">
Since Icinga Web 2, users in the Icinga configuration and the web authentication are separated, to allow
use of external authentication providers. This means that users and groups defined in the Icinga configuration are not available to Icinga Web 2. Instead it uses its own authentication
backend to fetch users and groups from, which must be configured separately.
</div>

#### Managing Users

When using a [Database
as authentication backend](authentication.md#authentication-configuration-db-authentication), it is possible to create, add and delete users directly in the frontend. This configuration
can be found at **Configuration > Authentication > Users **.

### Groups

If there is a big amount of users to manage, it would be tedious to specify each user
separately when referring to a bigger group of users often. Because of that, it is possible to group users together into groups.
A user can be member of multiple groups and will inherit all permissions and restrictions.

Like users, groups are identified solely by their **name** that is provided by
a **group backend**. For extended information on setting up group backends,
please read the chapter [Authentication](authentication.md#authentication).


#### Managing Groups

When using a [Database as an authentication backend](#authentication.md#authentication-configuration-db-authentication),
it is possible manage groups and group memberships directly in the frontend. This configuration
can be found at **Configuration > Authentication > Groups **.

## Roles

A role defines a set of **permissions** and **restrictions** and assigns
those to **users** and **groups**. For example, a role **admins** could define that certain
users have access to all configuration options, or another role **support**
could define that a list of users or groups is restricted to see only hosts and services
that match a specific query.

The actual permission of a certain user will be determined by merging the permissions and restrictions of the user itself and all the groups the user is part of. Permissions can
be simply added up, while restrictions follow a slighty more complex pattern, that is described
in the section [Stacking Filters](#stacking-filters).

### Configuration

Roles can be changed either through the icingaweb2 interface, by navigation
to the page **Configuration > Authentication > Roles**, or through editing the
configuration file:


/etc/icingaweb2/roles.ini


#### Introducing Example

To get you a quick start, here is an example of how a role definition could look like:


[winadmin]
users = "jdoe, janedoe"
groups = "admin"
permissions = "config/application/*, monitoring/commands/schedule-check"
monitoring/filter/objects = "host=*win*"


This example creates a role called **winadmin**, that grants all permissions in **config/application/** and ** monitoring/commands/schedule-check ** and additionally only
allows the hosts and services that match the filter ** host=\*win* ** to be displayed. The users
**jdoe** and **janedoe** and all members of the group **admin** will be affected
by this role.


#### Syntax

Each role is defined as a section, with the name of the role as section name. The following
attributes can be defined for each role in a default Icinga Web 2 installation:


| Key | Value |
|---------------------------|---------------------------------------------------------------------------------|
| users | A comma-separated list of user **user names** that are affected by this role |
| groups | A comma-separated list of **group names** that are affected by this role |
| permissions | A comma-separated list of **permissions** granted by this role |
| monitoring/filter/objects | A **filter expression** that restricts the access to services and hosts |



## <a id="permissions"></a> Permissions

Permissions can be used to allow users or groups certain **actions**. By default,
all actions are **prohibited** and must be allowed explicitly by a role for any user.

Each action in Icinga Web 2 is denoted by a **namespaced key**, which is used to order and
group those actions. All actions that affect the configuration of Icinga Web 2, are in a
namespace called **config**, while all configurations that affect authentication
are in the namespace **config/authentication**

**Wildcards** can be used to grant permission for all actions in a certain namespace.
The permission **config/ ** would grant permission to all configuration actions,
while just specifying a wildcard * would give permission for all actions.

When multiple roles assign permissions to the same user (either directly or indirectly
through a group) all permissions can simply be added together to get the users actual permission set.

#### Global permissions

| Name | Permits |
|-------------------------------------|-----------------------------------------------------------------|
| * | Allow everything, including module-specific permissions |
| config/* | Allow all configuration actions |
| config/application/* | Allow configuring IcingaWeb2 |
| config/application/general | Allow general settings, like logging or preferences |
| config/application/resources | Allow changing resources for retrieving data |
| config/application/userbackend | Allow changing backends for retrieving available users |
| config/application/usergroupbackend | Allow changing backends for retrieving available groups |
| config/authentication/* | Allow configuring IcingaWeb2 authentication mechanisms |
| config/authentication/users/* | Allow all user actions |
| config/authentication/users/show | Allow displaying avilable users |
| config/authentication/users/add | Allow adding a new user to the backend |
| config/authentication/users/edit | Allow editing an existing user in the backend |
| config/authentication/users/remove | Allow removing an existing user from the backend |
| config/authentication/groups/* | Allow all group actions |
| config/authentication/groups/show | Allow displaying all available groups |
| config/authentication/groups/add | Allow adding a new group to the backend |
| config/authentication/groups/edit | Allow editing existing groups in a backend |
| config/authentication/groups/remove | Allow removing existing groups from the backend |
| config/authentication/roles/* | Allow all role actions |
| config/authentication/roles/add | Allow adding a new role |
| config/authentication/roles/show | Allow displaying available roles |
| config/authentication/roles/edit | Allow changing an existing role |
| config/authentication/roles/remove | Allow removing an existing row |
| config/modules | Allow enabling or disable modules and module changing settings |


#### Monitoring module permissions

The built-in monitoring module defines an additional set of permissions, that
are described in detail in [monitoring module documentation](/icingaweb2/doc/module/doc/chapter/monitoring-security#monitoring-security).



## <a id="restrictions"></a> Restrictions

Restrictions can be used to define what a user or group can see by specifying
a filter expression. By default, when no restrictions are defined, a user will be able
to see every object available. When a restriction is specified for a certain object type
the user will only be able to see objects matched by those filters.


### Filterable Objects

Each filter expression consists of two parts: The **key** that defines **which** objects
to filter and the filter, that defines **what** to filter.

In a default Icinga Web 2 installations, the only objects that are filterable
are the objects provided by the monitoring module. The monitoring module provides
**hosts** and **services** as filterable objects:


| Keys | Restricsts |
|----------------------------|-----------------------------------------------|
| monitoring/filter/objects | Applies host and service filters to all hosts |


#### Filter Columns

Filters operate on object attributes. A complete list of all available filter columns on hosts and services can be found in
the [monitoring module documentation](/icingaweb2/doc/module/doc/chapter/monitoring-security#monitoring-security-restrictions).

### Filter Expressions

Any filter expression that is allowed in the filtered view, is also an allowed filter expression.
This means, that it is possible to define negations, wildcards, and even nested
filter expressions containing AND and OR-Clauses.

The filter expression will be **implicitly** added as an **AND-Clause** to each query on the filtered objects. The following shows the filter expression **host = \*win* ** being applied on ** monitoring/filter/objects **.


Regular filter query:

AND-- service_problem = 1
|
+--- service_handled = 0


With our restriction applied, any user affected by this restrictions will see the
results of this query instead:


AND-- host = *win*
|
+--AND-- service_problem = 1
|
+--- service_handled = 0


#### <a id="stacking-filters"></a> Stacking Filters

When multiple roles assign restrictions to the same user, either directly or indirectly
through a group, all filters will be combined using an **OR-Clause**, resulting in the final
expression:


AND -- OR-- $FILTER1
| |
| +-- $FILTER2
| |
| +-- $FILTER3
|
+--AND-- service_problem = 1
|
+--- service_handled = 0


As a result, a user is be able to see hosts that are matched by **ANY** of
the filter expressions. The following examples will show the usefulness of this behavior:

#### Example 1: Negation

[winadmin]
groups = "windows-admins"
monitoring/filter/objects = "host=*win*"

Will display only hosts and services whose host name contains **win**.

[webadmin]
groups = "web-admins"
monitoring/filter/objects = "host!=*win*"

Will only match hosts and services whose host name does **not** contain **win**

Notice that because of the behavior of two stacking filters, a user that is member of **windows-admins** and **web-admins**, will now be able to see both, Windows and non-Windows hosts and services.

#### Example 2: Hostgroups

[unix-server]
groups = "unix-admins"
monitoring/filter/objects = "(hostgroup_name=bsd-servers|hostgroup_name=linux-servers)"

This role allows all members of the group unix-admins to see hosts and services
that are part of the host-group linux-servers or the host-group bsd-servers.

## Troubleshooting

Q: I cannot see the menu for changing roles in Icinga Web 2

A: Your user lacks the permission to change the authentication configuration,
add a new role in roles.ini that gives your current user
the permission to access **config/authentication/**
65 changes: 65 additions & 0 deletions modules/doc/doc/security.md
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# <a id="monitoring-security"></a> Security

The monitoring module provides an additional set of restrictions and permissions
that can be used for access control. The following sections will list those
restrictions and permissions in detail:


## Permissions

The Icinga Web 2 monitoring plugin can send commands to the current Icinga2 instance
through the command pipe. A user needs specific permissions to be able to send those
commands when using the monitoring plugin.


| Name | Permits |
|---------------------------------------------|-----------------------------------------------------------------------------|
| monitoring/command/* | Allow all commands |
| monitoring/command/schedule-check | Allow scheduling host and service checks' |
| monitoring/command/acknowledge-problem | Allow acknowledging host and service problems |
| monitoring/command/remove-acknowledgement | Allow removing problem acknowledgements |
| monitoring/command/comment/* | Allow adding and deleting host and service comments |
| monitoring/command/comment/add | Allow commenting on hosts and services |
| monitoring/command/downtime/delete | Allow deleting host and service downtimes' |
| monitoring/command/process-check-result | Allow processing host and service check results |
| monitoring/command/feature/instance | Allow processing commands for toggling features on an instance-wide basis |
| monitoring/command/feature/object | Allow processing commands for toggling features on host and service objects |
| monitoring/command/send-custom-notification | Allow sending custom notifications for hosts and services |


## <a id="monitoring-security-restrictions"></a> Restrictions

The monitoring module allows filtering objects:


| Keys | Restricts |
|----------------------------|-----------------------------------------------|
| monitoring/filter/objects | Applies a filter to all hosts and services |


This filter will affect all hosts and services. Furthermore, it will also
affect all related objects, like notifications, downtimes or events. If a
service is hidden, all notifications, downtimes on that service will be hidden too.


### Filter Column Names

The following filter column names are available in filter expressions:


| Column |
|------------------------------------------------------|
| host |
| host_alias |
| host_display_name |
| host_name |
| hostgroup |
| hostgroup_alias |
| hostgroup_name |
| service |
| service_description |
| service_display_name |
| service_group |
| service_group_alias |
| service_group_name |
| + all custom variables prefixed with host or service |

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