openssl_rsa_public_key resource

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Use the openssl_rsa_public_key resource to generate RSA public key files for a given RSA private key.

New in Chef Client 14.0.

Syntax

The openssl_rsa_public_key resource has the following syntax:

openssl_rsa_public_key 'name' do
  group                    String
  mode                     Integer, String # default value: "0640"
  owner                    String
  path                     String # default value: 'name' unless specified
  private_key_content      String
  private_key_pass         String
  private_key_path         String
  action                   Symbol # defaults to :create if not specified
end

where:

  • openssl_rsa_public_key is the resource.
  • name is the name given to the resource block.
  • action identifies which steps the chef-client will take to bring the node into the desired state.
  • group, mode, owner, path, private_key_content, private_key_pass, and private_key_path are the properties available to this resource.

Actions

The openssl_rsa_public_key resource has the following actions:

:create
Default. Create the RSA public key.
:nothing
This resource block does not act unless notified by another resource to take action. Once notified, this resource block either runs immediately or is queued up to run at the end of the Chef Client run.

Properties

The openssl_rsa_public_key resource has the following properties:

group

Ruby Type: String

The group ownership applied to all files created by the resource.

mode

Ruby Type: Integer, String | Default Value: "0640"

The permission mode applied to all files created by the resource.

owner

Ruby Type: String

The owner applied to all files created by the resource.

path

Ruby Type: String | Default Value: The resource block's name

An optional property for specifying the path to the public key if it differs from the resource block’s name.

private_key_content

Ruby Type: String

The content of the private key, including new lines. This property is used in place of private_key_path in instances where you want to avoid having to first write the private key to disk.

private_key_pass

Ruby Type: String

The passphrase of the provided private key.

private_key_path

Ruby Type: String

The path to the private key file.

Common Resource Functionality

Chef resources include common properties, notifications, and resource guards.

Common Properties

The following properties are common to every resource:

ignore_failure

Ruby Type: true, false | Default Value: false

Continue running a recipe if a resource fails for any reason.

retries

Ruby Type: Integer | Default Value: 0

The number of attempts to catch exceptions and retry the resource.

retry_delay

Ruby Type: Integer | Default Value: 2

The retry delay (in seconds).

sensitive

Ruby Type: true, false | Default Value: false

Ensure that sensitive resource data is not logged by the chef-client.

Notifications

notifies

Ruby Type: Symbol, ‘Chef::Resource[String]’

A resource may notify another resource to take action when its state changes. Specify a 'resource[name]', the :action that resource should take, and then the :timer for that action. A resource may notify more than one resource; use a notifies statement for each resource to be notified.

A timer specifies the point during the Chef Client run at which a notification is run. The following timers are available:

:before
Specifies that the action on a notified resource should be run before processing the resource block in which the notification is located.
:delayed
Default. Specifies that a notification should be queued up, and then executed at the end of the Chef Client run.
:immediate, :immediately
Specifies that a notification should be run immediately, per resource notified.

The syntax for notifies is:

notifies :action, 'resource[name]', :timer
subscribes
Ruby Type: Symbol, ‘Chef::Resource[String]’

A resource may listen to another resource, and then take action if the state of the resource being listened to changes. Specify a 'resource[name]', the :action to be taken, and then the :timer for that action.

Note that subscribes does not apply the specified action to the resource that it listens to - for example:

file '/etc/nginx/ssl/example.crt' do
  mode '0600'
  owner 'root'
end

service 'nginx' do
  subscribes :reload, 'file[/etc/nginx/ssl/example.crt]', :immediately
end

In this case the subscribes property reloads the nginx service whenever its certificate file, located under /etc/nginx/ssl/example.crt, is updated. subscribes does not make any changes to the certificate file itself, it merely listens for a change to the file, and executes the :reload action for its resource (in this example nginx) when a change is detected.

A timer specifies the point during the Chef Client run at which a notification is run. The following timers are available:

:before
Specifies that the action on a notified resource should be run before processing the resource block in which the notification is located.
:delayed
Default. Specifies that a notification should be queued up, and then executed at the end of the Chef Client run.
:immediate, :immediately
Specifies that a notification should be run immediately, per resource notified.

The syntax for subscribes is:

subscribes :action, 'resource[name]', :timer

Guards

A guard property can be used to evaluate the state of a node during the execution phase of the chef-client run. Based on the results of this evaluation, a guard property is then used to tell the chef-client if it should continue executing a resource. A guard property accepts either a string value or a Ruby block value:

  • A string is executed as a shell command. If the command returns 0, the guard is applied. If the command returns any other value, then the guard property is not applied. String guards in a powershell_script run Windows PowerShell commands and may return true in addition to 0.
  • A block is executed as Ruby code that must return either true or false. If the block returns true, the guard property is applied. If the block returns false, the guard property is not applied.

A guard property is useful for ensuring that a resource is idempotent by allowing that resource to test for the desired state as it is being executed, and then if the desired state is present, for the chef-client to do nothing.

The following properties can be used to define a guard that is evaluated during the execution phase of the chef-client run:

not_if
Prevent a resource from executing when the condition returns true.
only_if
Allow a resource to execute only if the condition returns true.

Examples

Create a public key from a private key file

openssl_rsa_public_key '/etc/example/key.pub' do
  private_key_path '/etc/example/key.pem'
end

Create a public key from a private key, without writing the private key to disk

You can provide the private key content as a string to the openssl_rsa_public_key resource. In this example we just pass a string, but this content could be loaded from an encrypted data bag or other secure storage.

openssl_rsa_public_key '/etc/example/key.pub' do
  private_key_content 'KEY_CONTENT_HERE_AS_A_STRING'
end