Install this package:
emerge -a net-analyzer/passivedns
If the package is masked, you can unmask it using the autounmask tool or standard emerge options:
autounmask net-analyzer/passivedns
Or alternatively:
emerge --autounmask-write -a net-analyzer/passivedns
<pkgmetadata> <maintainer type="person"> <email>maintainer-wanted@gentoo.org</email> </maintainer> </pkgmetadata>