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community.crypto.openssh_cert – Generate OpenSSH host or user certificates.

Note

This plugin is part of the community.crypto collection (version 1.9.6).

You might already have this collection installed if you are using the ansible package. It is not included in ansible-core. To check whether it is installed, run ansible-galaxy collection list.

To install it, use: ansible-galaxy collection install community.crypto.

To use it in a playbook, specify: community.crypto.openssh_cert.

Synopsis

  • Generate and regenerate OpenSSH host or user certificates.

Requirements

The below requirements are needed on the host that executes this module.

  • ssh-keygen

Parameters

Parameter Choices/Defaults Comments
attributes
string
added in 2.3 of ansible.builtin
The attributes the resulting file or directory should have.
To get supported flags look at the man page for chattr on the target system.
This string should contain the attributes in the same order as the one displayed by lsattr.
The = operator is assumed as default, otherwise + or - operators need to be included in the string.

aliases: attr
force
boolean
    Choices:
  • no ←
  • yes
Should the certificate be regenerated even if it already exists and is valid.
Equivalent to regenerate=always.
group
string
Name of the group that should own the file/directory, as would be fed to chown.
identifier
string
Specify the key identity when signing a public key. The identifier that is logged by the server when the certificate is used for authentication.
mode
raw
The permissions the resulting file or directory should have.
For those used to /usr/bin/chmod remember that modes are actually octal numbers. You must either add a leading zero so that Ansible's YAML parser knows it is an octal number (like 0644 or 01777) or quote it (like '644' or '1777') so Ansible receives a string and can do its own conversion from string into number.
Giving Ansible a number without following one of these rules will end up with a decimal number which will have unexpected results.
As of Ansible 1.8, the mode may be specified as a symbolic mode (for example, u+rwx or u=rw,g=r,o=r).
If mode is not specified and the destination file does not exist, the default umask on the system will be used when setting the mode for the newly created file.
If mode is not specified and the destination file does exist, the mode of the existing file will be used.
Specifying mode is the best way to ensure files are created with the correct permissions. See CVE-2020-1736 for further details.
options
list / elements=string
Specify certificate options when signing a key. The option that are valid for user certificates are:
clear: Clear all enabled permissions. This is useful for clearing the default set of permissions so permissions may be added individually.
force-command=command: Forces the execution of command instead of any shell or command specified by the user when the certificate is used for authentication.
no-agent-forwarding: Disable ssh-agent forwarding (permitted by default).
no-port-forwarding: Disable port forwarding (permitted by default).
no-pty: Disable PTY allocation (permitted by default).
no-user-rc: Disable execution of ~/.ssh/rc by sshd (permitted by default).
no-x11-forwarding: Disable X11 forwarding (permitted by default)
permit-agent-forwarding: Allows ssh-agent forwarding.
permit-port-forwarding: Allows port forwarding.
permit-pty: Allows PTY allocation.
permit-user-rc: Allows execution of ~/.ssh/rc by sshd.
permit-x11-forwarding: Allows X11 forwarding.
source-address=address_list: Restrict the source addresses from which the certificate is considered valid. The address_list is a comma-separated list of one or more address/netmask pairs in CIDR format.
At present, no options are valid for host keys.
owner
string
Name of the user that should own the file/directory, as would be fed to chown.
path
path / required
Path of the file containing the certificate.
pkcs11_provider
string
added in 1.1.0 of community.crypto
To use a signing key that resides on a PKCS#11 token, set this to the name (or full path) of the shared library to use with the token. Usually libpkcs11.so.
If this is set, signing_key needs to point to a file containing the public key of the CA.
principals
list / elements=string
Certificates may be limited to be valid for a set of principal (user/host) names. By default, generated certificates are valid for all users or hosts.
public_key
path
The path to the public key that will be signed with the signing key in order to generate the certificate.
Required if state is present.
regenerate
string
added in 1.8.0 of community.crypto
    Choices:
  • never
  • fail
  • partial_idempotence ←
  • full_idempotence
  • always
When never the task will fail if a certificate already exists at path and is unreadable otherwise a new certificate will only be generated if there is no existing certificate.
When fail the task will fail if a certificate already exists at path and does not match the module's options.
When partial_idempotence an existing certificate will be regenerated based on serial, signature_algorithm, type, valid_from, valid_to, valid_at, and principals.
When full_idempotence identifier, options, public_key, and signing_key are also considered when compared against an existing certificate.
always is equivalent to force=true.
selevel
string
The level part of the SELinux file context.
This is the MLS/MCS attribute, sometimes known as the range.
When set to _default, it will use the level portion of the policy if available.
serial_number
integer
Specify the certificate serial number. The serial number is logged by the server when the certificate is used for authentication. The certificate serial number may be used in a KeyRevocationList. The serial number may be omitted for checks, but must be specified again for a new certificate. Note: The default value set by ssh-keygen is 0.
serole
string
The role part of the SELinux file context.
When set to _default, it will use the role portion of the policy if available.
setype
string
The type part of the SELinux file context.
When set to _default, it will use the type portion of the policy if available.
seuser
string
The user part of the SELinux file context.
By default it uses the system policy, where applicable.
When set to _default, it will use the user portion of the policy if available.
signature_algorithm
string
added in 1.10.0 of community.crypto
    Choices:
  • ssh-rsa
  • rsa-sha2-256
  • rsa-sha2-512
As of OpenSSH 8.2 the SHA-1 signature algorithm for RSA keys has been disabled and ssh will refuse host certificates signed with the SHA-1 algorithm. OpenSSH 8.1 made rsa-sha2-512 the default algorithm when acting as a CA and signing certificates with a RSA key. However, for OpenSSH versions less than 8.1 the SHA-2 signature algorithms, rsa-sha2-256 or rsa-sha2-512, must be specified using this option if compatibility with newer ssh clients is required. Conversely if hosts using OpenSSH version 8.2 or greater must remain compatible with ssh clients using OpenSSH less than 7.2, then ssh-rsa can be used when generating host certificates (a corresponding change to the sshd_config to add ssh-rsa to the CASignatureAlgorithms keyword is also required).
Using any value for this option with a non-RSA signing_key will cause this module to fail.
Note: OpenSSH versions prior to 7.2 do not support SHA-2 signature algorithms for RSA keys and OpenSSH versions prior to 7.3 do not support SHA-2 signature algorithms for certificates.
See https://www.openssh.com/txt/release-8.2 for more information.
signing_key
path
The path to the private openssh key that is used for signing the public key in order to generate the certificate.
If the private key is on a PKCS#11 token (pkcs11_provider), set this to the path to the public key instead.
Required if state is present.
state
string
    Choices:
  • present ←
  • absent
Whether the host or user certificate should exist or not, taking action if the state is different from what is stated.
type
string
    Choices:
  • host
  • user
Whether the module should generate a host or a user certificate.
Required if state is present.
unsafe_writes
boolean
added in 2.2 of ansible.builtin
    Choices:
  • no ←
  • yes
Influence when to use atomic operation to prevent data corruption or inconsistent reads from the target file.
By default this module uses atomic operations to prevent data corruption or inconsistent reads from the target files, but sometimes systems are configured or just broken in ways that prevent this. One example is docker mounted files, which cannot be updated atomically from inside the container and can only be written in an unsafe manner.
This option allows Ansible to fall back to unsafe methods of updating files when atomic operations fail (however, it doesn't force Ansible to perform unsafe writes).
IMPORTANT! Unsafe writes are subject to race conditions and can lead to data corruption.
use_agent
boolean
added in 1.3.0 of community.crypto
    Choices:
  • no ←
  • yes
Should the ssh-keygen use a CA key residing in a ssh-agent.
valid_at
string
Check if the certificate is valid at a certain point in time. If it is not the certificate will be regenerated. Time will always be interpreted as UTC. Mainly to be used with relative timespec for valid_from and / or valid_to. Note that if using relative time this module is NOT idempotent.
valid_from
string
The point in time the certificate is valid from. Time can be specified either as relative time or as absolute timestamp. Time will always be interpreted as UTC. Valid formats are: [+-]timespec | YYYY-MM-DD | YYYY-MM-DDTHH:MM:SS | YYYY-MM-DD HH:MM:SS | always where timespec can be an integer + [w | d | h | m | s] (e.g. +32w1d2h. Note that if using relative time this module is NOT idempotent.
Required if state is present.
valid_to
string
The point in time the certificate is valid to. Time can be specified either as relative time or as absolute timestamp. Time will always be interpreted as UTC. Valid formats are: [+-]timespec | YYYY-MM-DD | YYYY-MM-DDTHH:MM:SS | YYYY-MM-DD HH:MM:SS | forever where timespec can be an integer + [w | d | h | m | s] (e.g. +32w1d2h. Note that if using relative time this module is NOT idempotent.
Required if state is present.

Examples

- name: Generate an OpenSSH user certificate that is valid forever and for all users
  community.crypto.openssh_cert:
    type: user
    signing_key: /path/to/private_key
    public_key: /path/to/public_key.pub
    path: /path/to/certificate
    valid_from: always
    valid_to: forever

# Generate an OpenSSH host certificate that is valid for 32 weeks from now and will be regenerated
# if it is valid for less than 2 weeks from the time the module is being run
- name: Generate an OpenSSH host certificate with valid_from, valid_to and valid_at parameters
  community.crypto.openssh_cert:
    type: host
    signing_key: /path/to/private_key
    public_key: /path/to/public_key.pub
    path: /path/to/certificate
    valid_from: +0s
    valid_to: +32w
    valid_at: +2w

- name: Generate an OpenSSH host certificate that is valid forever and only for example.com and examplehost
  community.crypto.openssh_cert:
    type: host
    signing_key: /path/to/private_key
    public_key: /path/to/public_key.pub
    path: /path/to/certificate
    valid_from: always
    valid_to: forever
    principals:
        - example.com
        - examplehost

- name: Generate an OpenSSH host Certificate that is valid from 21.1.2001 to 21.1.2019
  community.crypto.openssh_cert:
    type: host
    signing_key: /path/to/private_key
    public_key: /path/to/public_key.pub
    path: /path/to/certificate
    valid_from: "2001-01-21"
    valid_to: "2019-01-21"

- name: Generate an OpenSSH user Certificate with clear and force-command option
  community.crypto.openssh_cert:
    type: user
    signing_key: /path/to/private_key
    public_key: /path/to/public_key.pub
    path: /path/to/certificate
    valid_from: always
    valid_to: forever
    options:
        - "clear"
        - "force-command=/tmp/bla/foo"

- name: Generate an OpenSSH user certificate using a PKCS#11 token
  community.crypto.openssh_cert:
    type: user
    signing_key: /path/to/ca_public_key.pub
    pkcs11_provider: libpkcs11.so
    public_key: /path/to/public_key.pub
    path: /path/to/certificate
    valid_from: always
    valid_to: forever

Return Values

Common return values are documented here, the following are the fields unique to this module:

Key Returned Description
filename
string
changed or success
path to the certificate

Sample:
/tmp/certificate-cert.pub
info
list / elements=string
change or success
Information about the certificate. Output of ssh-keygen -L -f.
type
string
changed or success
type of the certificate (host or user)

Sample:
host


Authors

  • David Kainz (@lolcube)

© 2012–2018 Michael DeHaan
© 2018–2021 Red Hat, Inc.
Licensed under the GNU General Public License version 3.
https://docs.ansible.com/ansible/latest/collections/community/crypto/openssh_cert_module.html