slapo-remoteauth — Delegate authentication requests to remote directories, e.g. Active Directory
ETCDIR/slapd.conf
The remoteauth
overlay to slapd(8) provides
passthrough authentication to remote directory servers, e.g.
Active Directory, for LDAP simple bind operations. The local
LDAP entry referenced in the bind operation is mapped to its
counterpart in the remote directory. An LDAP bind operation
is performed against the remote directory and results are
returned based on those of the remote operation.
A slapd server configured with the remoteauth overlay handles an
authentication request based on the presence of userPassword in the local
entry. If the userPassword is present,
authentication is performed locally, otherwise the remoteauth overlay performs
the authentication request to the configured remote directory
server.
The following options can be applied to the remoteauth overlay within the
slapd.conf file. All options should follow the overlay remoteauth directive.
This directive adds the remoteauth overlay to
the current database, see slapd.conf(5) for
details.
Attribute in the local entry that is used to store the bind DN to a remote directory server.
For a non-Windows deployment, a domain can be considered as a collection of one or more hosts to which slapd server authentcates against on behalf of authenticating users. For a given domain name, the mapping specifies the target server(s), e.g., Active Directory domain controller(s), to connect to via LDAP. The second argument can be given either as a hostname, an LDAP URI, or a file containing a list of hostnames/URIs, one per line. The hostnames are tried in sequence until the connection succeeds.
This option can be provided more than once to provide mapping information for different domains. For example:
remoteauth_mapping americas file:///path/to/americas.domain.hosts
remoteauth_mapping asiapacific file:///path/to/asiapacific.domain.hosts
remoteauth_mapping emea emeadc1.emea.example.com
Attribute in the local entry that specifies the domain name, any text after "\" or ":" is ignored.
Default domain.
Fallback server to connect to for domains not
specified in remoteauth_mapping.
Number of connection retries attempted. Default is 3.
Whether to store the password in the local entry on successful bind. Default is off.
remoteauth_tls
[starttls=yes]
[tls_cert=<file>]
[tls_key=<file>]
[tls_cacert=<file>]
[tls_cacertdir=<path>]
[tls_reqcert=never|allow|try|demand]
[tls_reqsan=never|allow|try|demand]
[tls_cipher_suite=<ciphers>]
[tls_ecname=<names>]
[tls_crlcheck=none|peer|all]
Remoteauth specific TLS configuration, see slapd.conf(5) for more details on each of the parameters and defaults.
Mapping between remote server hostnames and their
public key hashes. Only one mapping per hostname is
supported and if any pins are specified, all hosts need
to be pinned. If set, pinning is in effect regardless
of whether or not certificate name validation is
enabled by tls_reqcert.
A typical example configuration of remoteauth overlay for AD is
shown below (as a slapd.conf(5) snippet):
database <database> #... overlay remoteauth remoteauth_dn_attribute seeAlso remoteauth_domain_attribute associatedDomain remoteauth_default_realm americas.example.com remoteauth_mapping americas file:///home/ldap/etc/remoteauth.americas remoteauth_mapping emea emeadc1.emea.example.com remoteauth_tls starttls=yes tls_reqcert=demand tls_cacert=/home/ldap/etc/example-ca.pem remoteauth_tls_peerkey_hash ldap.americas.tld sha256:Bxv3MkLoDm6gt/iDfeGNdNNqa5TTpPDdIwvZM/cIgeo=
Where seeAlso contains the AD bind DN for the user, associatedDomain contains the Windows Domain Id in the form of <NT-domain-name>:<NT-username> in which anything following, including ":", is ignored.