openssh_cert – Generate OpenSSH host or user certificates

New in version 2.8.

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
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.
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
string
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).
As of Ansible 2.6, the mode may also be the special string preserve.
When set to preserve the file will be given the same permissions as the source file.
options
list
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.
principals
list
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 / required
The path to the public key that will be signed with the signing key in order to generate the certificate.
selevel
string
Default:
"s0"
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.
signing_key
path / required
The path to the private openssh key that is used for signing the public key in order to generate the certificate.
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 / required
    Choices:
  • host
  • user
Whether the module should generate a host or a user certificate.
unsafe_writes
boolean
added in 2.2
    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.
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 / required
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.
valid_to
string / required
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.

Examples

# Generate an OpenSSH user certificate that is valid forever and for all users
- 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
- 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

# Generate an OpenSSH host certificate that is valid forever and only for example.com and examplehost
- 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

# Generate an OpenSSH host Certificate that is valid from 21.1.2001 to 21.1.2019
- 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"

# Generate an OpenSSH user Certificate with clear and force-command option:
- 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"

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
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


Status

Authors

  • David Kainz (@lolcube)

Hint

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