/usr/share/doc/libpam-ldap/examples/pam.d/vlock is in libpam-ldap 186-4.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 | #%PAM-1.0
auth sufficient /lib/security/pam_ldap.so
auth required /lib/security/pam_pwdb.so shadow nullok
|