man 1 sss_ssh_authorizedkeys

SSS_SSH_AUTHORIZEDKE(1)        SSSD Manual pages       SSS_SSH_AUTHORIZEDKE(1)

NAME
       sss_ssh_authorizedkeys - get OpenSSH authorized keys

SYNOPSIS
       sss_ssh_authorizedkeys [options] USER

DESCRIPTION
       sss_ssh_authorizedkeys acquires SSH public keys for user USER and
       outputs them in OpenSSH authorized_keys format (see the
       "AUTHORIZED_KEYS FILE FORMAT" section of sshd(8) for more information).

       sshd(8) can be configured to use sss_ssh_authorizedkeys for public key
       user authentication if it is compiled with support for
       "AuthorizedKeysCommand" option. Please refer to the sshd_config(5) man
       page for more details about this option.

       If "AuthorizedKeysCommand" is supported, sshd(8) can be configured to
       use it by putting the following directives in sshd_config(5):

             AuthorizedKeysCommand /usr/bin/sss_ssh_authorizedkeys
             AuthorizedKeysCommandUser nobody

   KEYS FROM CERTIFICATES
       In addition to the public SSH keys for user USER sss_ssh_authorizedkeys
       can return public SSH keys derived from the public key of a X.509
       certificate as well.

       To enable this the "ssh_use_certificate_keys" option must be set to
       true (default) in the [ssh] section of sssd.conf. If the user entry
       contains certificates (see "ldap_user_certificate" in sssd-ldap(5) for
       details) or there is a certificate in an override entry for the user
       (see sss_override(8) or sssd-ipa(5) for details) and the certificate is
       valid SSSD will extract the public key from the certificate and convert
       it into the format expected by sshd.

       Besides "ssh_use_certificate_keys" the options

       o   ca_db

       o   p11_child_timeout

       o   certificate_verification

       can be used to control how the certificates are validated (see
       sssd.conf(5) for details).

       The validation is the benefit of using X.509 certificates instead of
       SSH keys directly because e.g. it gives a better control of the
       lifetime of the keys. When the ssh client is configured to use the
       private keys from a Smartcard with the help of a PKCS#11 shared library
       (see ssh(1) for details) it might be irritating that authentication is
       still working even if the related X.509 certificate on the Smartcard is
       already expired because neither ssh nor sshd will look at the
       certificate at all.

       It has to be noted that the derived public SSH key can still be added
       to the authorized_keys file of the user to bypass the certificate
       validation if the sshd configuration permits this.

OPTIONS
       -d,--domain DOMAIN
           Search for user public keys in SSSD domain DOMAIN.

       -?,--help
           Display help message and exit.

EXIT STATUS
       In case of success, an exit value of 0 is returned. Otherwise, 1 is
       returned.

SEE ALSO
       sssd(8), sssd.conf(5), sssd-ldap(5), sssd-ldap-attributes(5), sssd-
       krb5(5), sssd-simple(5), sssd-ipa(5), sssd-ad(5), sssd-files(5), sssd-
       sudo(5), sssd-session-recording(5), sss_cache(8), sss_debuglevel(8),
       sss_obfuscate(8), sss_seed(8), sssd_krb5_locator_plugin(8),
       sss_ssh_authorizedkeys(8), sss_ssh_knownhostsproxy(8), sssd-ifp(5),
       pam_sss(8).  sss_rpcidmapd(5) sssd-systemtap(5)

AUTHORS
       The SSSD upstream - https://github.com/SSSD/sssd/

SSSD                              04/07/2025           SSS_SSH_AUTHORIZEDKE(1)