Passwd (passwd)

User is looked up using getpwnam() call, which usually looks into /etc/passwd file, but depending on the NSS configuration it may also look up the user from, e.g., LDAP database.

Most commonly used as a userdb.

The lookup is by default done in the auth worker processes. If you have only a small local passwd file, you can avoid having extra auth worker processes by disabling it:

userdb passwd {
  use_worker = yes
}

Field Overriding and Extra Fields

It's possible to override fields from passwd and add userdb: Extra Fields.

For example:

userdb passwd {
  fields {
    home = /var/mail/%{user | username}
    mail_driver = maildir
    mail_path = /var/mail/%{user | username}/Maildir
  }
}

This uses the UID and GID fields from passwd, but home directory is overridden. Also the default Mail Location Setting setting is overridden.

INFO

userdb_fields_import_all defaults to yes. If it is set to no the fields to be imported need to be explicitly defined.

userdb passwd {
  fields_import_all = no
  fields {
    uid = %{passwd:uid}
    gid = %{passwd:gid}
    home = /var/mail/%{user | username}
    mail_driver = maildir
    mail_path = /var/mail/%{user | username}/Maildir
  }
}

Passwd as a passdb

Many systems use shadow passwords nowadays so passwd doesn't usually work as a password database. BSDs are an exception to this, they still set the password field even with shadow passwords.

With FreeBSD, passwd doesn't work as a password database because the password field is replaced by a *. But you can use passwd-file authentication database instead.