configure ubuntu for stig id SRG-OS-000021-GPOS-00005

system/stig/ubuntu/files/common-auth

+#
+# /etc/pam.d/common-auth - authentication settings common to all services
+#
+# This file is included from other service-specific PAM config files,
+# and should contain a list of the authentication modules that define
+# the central authentication scheme for use on the system
+# (e.g., /etc/shadow, LDAP, Kerberos, etc.).  The default is to use the
+# traditional Unix authentication mechanisms.
+#
+# As of pam 1.0.1-6, this file is managed by pam-auth-update by default.
+# To take advantage of this, it is recommended that you configure any
+# local modules either before or after the default block, and use
+# pam-auth-update to manage selection of other modules.  See
+# pam-auth-update(8) for details.
+auth required pam_tally2.so onerr=fail deny=3
+# here are the per-package modules (the "Primary" block)
+auth    [success=1 default=ignore]      pam_unix.so nullok_secure
+# here's the fallback if no module succeeds
+auth    requisite                       pam_deny.so
+# prime the stack with a positive return value if there isn't one already;
+# this avoids us returning an error just because nothing sets a success code
+# since the modules above will each just jump around
+auth    required                        pam_permit.so
+# and here are more per-package modules (the "Additional" block)
+# end of pam-auth-update config