DISCLAIMER: There is no guarantee that anything here is safe to use. Use at your own risk.
Miscellaneous things I have cooked up.

FRR related patches for things like nhrp ospf bgp. Also there is an nhrp event handler script.

These scripts implement a framework for quagga based RTBH management, as well as external DB (sqlite) management of the RTBH and importation of external lists and related sundries.

This script is designed to detect, log and counteract uknown frame floods in an IPv4 switched ethernet environment. Its large and complex supports vlans and includes things like an arpcache, router detection, proxy arp detection and almost everything else minus the kitchen sink.

These patches change vlan tag handling and add options -0 -t -T -S -p -C to arping utility from the iputils project.

This patch adds this option to cut from GNU Coreutils.

"-z, --squeeze-delimiters treat consecutive delimiters as one"

This is a linked list implementation, suitable for drop in compilation into your sources. I find it usefull. You may find it naive incomplete and buggy. Enjoy.

This is a traceroute program I saw referenced in nanog material.

Printline is a program I use for scripts to selectively print its input lines. In its simplest form it may be used to loop your input one line at a time. Of course you could use read for at least some of this programs functionality.

Spool-remailer is a program written primarily to be used for remailing mbox spool files to users who have moved from a server before downloading their email. Of course, this was before I saw formail(1) which is pretty much a feature superset of this program for more general tasks.