Difference between revisions of "DNSSEC"

Revision as of 12:02, 11 November 2013

Facts

• Wikipedia:Domain Name System Security Extensions
• http://www.dnssec.net/
  • http://www.dnssec.net/practical-documents
  • http://www.dnssec.net/rfc
• https://www.iana.org/dnssec/
• https://www.dnssec-tools.org/
• http://linux.die.net/man/1/sshfp
• https://bugs.archlinux.org/task/20325 - [DNSSEC] Add DNS validation support to ArchLinux

DNSSEC Packages

• dnssec-anchors
  • essential package contains keys to internet from IANA stored in /usr/share/dnssec-trust-anchors/
  • VERY important!
• ldns
  • DNS(SEC) library libldns
  • drill tool (like dig with DNSSEC support)
    • can be used for basic DNSSEC validation. eg.:
      • Should success (return 0):
        • drill -TD nic.cz #valid DNSSEC key
        • drill -TD google.com #not signed domain
      • Should fail (simulating fraudent DNS records):
        • drill -TD rhybar.cz
        • drill -TD badsign-a.test.dnssec-tools.org
      • to use root-zone trust anchor add option -k /usr/share/dnssec-trust-anchors/root-anchor.key
• dnssec-tools^AUR (package is very experimental and volatile right now)
  • https://www.dnssec-tools.org/
  • another good library libval which can add DNSSEC support to lots of programs
    • https://www.dnssec-tools.org/wiki/index.php/DNSSEC_Applications
  • some tools https://www.dnssec-tools.org/wiki/index.php/DNSSEC-Tools_Components
    • https://www.dnssec-tools.org/wiki/index.php/Applications
  • libval-shim LD_PRELOAD library to enable DNSSEC for lots of DNSSEC unaware programs http://www.dnssec-tools.org/docs/tool-description/libval_shim.html
  • PERL API
• openssh-dnssec^AUR
  • see lower on this page
• sshfp^AUR
  • Generates DNS SSHFP-type records from SSH public keys from public keys from a known_hosts file or from scanning the host's sshd daemon.
  • not directly related to DNSSEC, but i guess this will become very popular because of DNSSEC
• opendnssec^AUR
  • Signs DNS zones to be later published by a DNS server (bind, nsd, etc.)
  • Automates refreshing signatures, key rollovers

Howto enable DNSSEC in specific software

If you want full support of DNSSEC, you need each single application to use DNSSEC validation. It can be done using several ways:

• patches
  • https://www.dnssec-tools.org/wiki/index.php/DNSSEC_Applications
  • https://www.dnssec-tools.org/wiki/index.php/DNSSEC_Application_Development
• plugins, extensions, wrappers
• universal LD_PRELOAD wrapper
  • overriding calls to: gethostbyname(3), gethostbyaddr(3), getnameinfo(3), getaddrinfo(3), res_query(3)
  • libval-shim from dnssec-tools: http://www.dnssec-tools.org/docs/tool-description/libval_shim.html
• DNS proxy

OpenSSH (fixes only weak point in SSH design)

• dnssec-tools + patch: https://www.dnssec-tools.org/wiki/index.php/Ssh
  • http://www.dnssec-tools.org/readme/README.ssh
• openssh-dnssec^AUR wrapper
  • DNSSEC (ldns) wrapper for OpenSSH client.
  • instantly adds minimal DNSSEC support to ssh (no SSHFP support).
  • usage: alias ssh=ssh-dnssec

Firefox (secure browsing - enchancment of HTTPS)

• DNSSEC Validator plugin https://addons.mozilla.org/en-US/firefox/addon/64247/
• DNSSEC Drill plugin http://nlnetlabs.nl/projects/drill/drill_extension.html
  • you need ldns and dnssec-root-zone-trust-anchors packages for this plugin
• dnssec-tools + firefox patch: https://www.dnssec-tools.org/wiki/index.php/Firefox

Chromium/Google Chrome (secure browsing - enchancment of HTTPS)

• Vote for #50874
  • Patches not yet...
  • DNSSEC Drill extension (EXPERIMENTAL!)
    • you need ldns and dnssec-root-zone-trust-anchors packages for this plugin

BIND (serving signed DNS zones)

• See BIND for more information on BIND
• http://www.dnssec.net/practical-documents
  • http://www.cymru.com/Documents/secure-bind-template.html (configuration template!)
  • http://www.bind9.net/manuals
  • http://www.bind9.net/BIND-FAQ
• http://blog.techscrawl.com/2009/01/13/enabling-dnssec-on-bind/
• Or use an external mechanisms such as OpenDNSSEC (fully-automatic key rollover)

Postfix (fight spam and frauds)

• dnssec-tools + patch

jabberd (fight spam and frauds)

• dnssec-tools + patch

Thunderbird (secure logins)

• dnssec-tools + patch

lftp (secure downloads and logins)

• dnssec-tools + patch

wget (secure downloads)

• dnssec-tools + patch

proftpd

• dnssec-tools + patch

Sendmail (fight spam and frauds)

• dnssec-tools + patch

LibSPF

• dnssec-tools + patch

ncftp (secure downloads and logins)

• dnssec-tools + patch

libpurple (pidgin + finch -> secure messaging)

• no patches yet

• Vote for #12413

DNSSEC Hardware

You can check if your router, modem, AP, etc. supports DNSSEC (many different features) using dnssec-tester (Python and GTK+ based app) to know if it is DNSSEC-compatible, and using this tool you can also upload gathered data to a server, so other users and manufacturers can be informed about compatibility of their devices and eventualy fix the firmware (they will be probably urged to do so). (Before running dnssec-tester please make sure, that you do not have any other nameservers in /etc/resolv.conf). You can also find the results of performed tests on the dnssec-tester website.

See Also

• AppArmor