Difference between revisions of "DNSSEC"

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{{Related|Unbound#DNSSEC validation}}
 
{{Related|Unbound#DNSSEC validation}}
 
{{Related articles end}}
 
{{Related articles end}}
{{Poor writing|More a draft than an article|Talk:Style#Reworking}}
 
  
 
From [[W:Domain Name System Security Extensions]]:
 
From [[W:Domain Name System Security Extensions]]:
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== Basic DNSSEC validation ==
 
== Basic DNSSEC validation ==
 +
 +
{{Note|Further setup is required for your DNS lookups DNSSEC by default. See [[#Install a DNSSEC-aware validating recursive server]] and [[#Enable DNSSEC in specific software]].}}
  
 
=== Installation ===
 
=== Installation ===
Line 43: Line 44:
 
  ;;[S] self sig OK; [B] bogus; [T] trusted
 
  ;;[S] self sig OK; [B] bogus; [T] trusted
  
== Deploy a DNSSEC capable recursive resolver ==
+
== Install a DNSSEC-aware validating recursive server ==
 
 
To use DNSSEC system-wide, you can use a recursive resolver that is DNSSEC capable, so that all DNS lookups go through the recursive resolver. [[BIND]] and [[unbound]] are two options.
 
 
 
== Howto enable DNSSEC in specific software ==
 
 
 
{{Remove|Disorganized. Just a list that says to patch software. Not practical.}}
 
 
 
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
 
 
 
=== [[Firefox]] (secure browsing - enhancement 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]]/<s>Google Chrome</s> (secure browsing - enhancement of HTTPS) ===
 
 
 
* Vote for [http://code.google.com/p/chromium/issues/detail?id=50874 #50874]
 
** Patches not yet...
 
** [http://chromium.googlecode.com/issues/attachment?aid=-8803347052009476090&name=chromium-drill-dnssec-validator.zip&token=6e3489c4e5c62bfaae02516be442d7da 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) ===
+
To use DNSSEC system-wide, you can use a validating recursive resolver that is DNSSEC-aware, so that all DNS lookups go through the recursive resolver. [[BIND]] and [[unbound]] are two options that you can setup. Note that each requires specific options to enable their DNSSEC validation feature.
  
* dnssec-tools + patch
+
If you attempt to visit a site with a bogus (spoofed) IP address, the validing resolver (i.e., BIND or unbound) will prevent you from receiving the invalid DNS data and your browser (or other application) will be told there is no such host. Since all DNS lookups go through the validing resolver, you do not need software that has DNSSEC support built-in when using this option.
  
=== [[Thunderbird]] (secure logins) ===
+
== Enable DNSSEC in specific software ==
  
* dnssec-tools + patch
+
If not you choose not to [[#Install a DNSSEC-aware validating recursive server]], you need to use software that has DNSSEC support builtin in order to use its features. Often this means you must patch the software yourself. A list of several patched applications is found [https://www.dnssec-tools.org/wiki/index.php?title=DNSSEC_Applications here]. Additionally some web browsers have extensions or add-ons that can be installed to implement DNSSEC without patching the program.
 
 
=== 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 [http://developer.pidgin.im/ticket/12413 #12413]
 
  
 
== DNSSEC Hardware ==
 
== DNSSEC Hardware ==
Line 136: Line 58:
 
You can check if your router, modem, AP, etc. supports DNSSEC (many different features) using [http://www.dnssec-tester.cz/ 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 {{ic|/etc/resolv.conf}}). You can also find the results of performed tests on the [http://www.dnssec-tester.cz/ dnssec-tester] website.
 
You can check if your router, modem, AP, etc. supports DNSSEC (many different features) using [http://www.dnssec-tester.cz/ 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 {{ic|/etc/resolv.conf}}). You can also find the results of performed tests on the [http://www.dnssec-tester.cz/ dnssec-tester] website.
  
== See Also ==
+
== See also ==
 
+
* [http://dnssec.vs.uni-due.de/ DNSSEC Resolver Test] - a simple test to see if you have DNSSEC implemented on your machine.
* [[AppArmor]]
+
* [https://www.dnssec-tools.org/ DNSSEC-Tools]
 +
* [http://dnsviz.net DNSSEC Visualizer] - a tool for visualizing the status of a DNS zone.
 +
* [https://access.redhat.com/documentation/en-US/Red_Hat_Enterprise_Linux/7/html/Security_Guide/sec-Securing_DNS_Traffic_with_DNSSEC.html RedHat: Securing DNS Traffic with DNSSEC] - thorough article on implementing DNSSEC with ''unbound''. Note that some tools are RedHat specific and not found in Arch Linux.
 
* [[Wikipedia:Domain Name System Security Extensions]]
 
* [[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
 
* [http://dnsviz.net DNSSEC Visualizer]
 

Revision as of 11:30, 23 April 2017

From W:Domain Name System Security Extensions:

The Domain Name System Security Extensions (DNSSEC) is a suite of Internet Engineering Task Force (IETF) specifications for securing certain kinds of information provided by the Domain Name System (DNS) as used on Internet Protocol (IP) networks. It is a set of extensions to DNS which provide to DNS clients (resolvers) origin authentication of DNS data, authenticated denial of existence, and data integrity, but not availability or confidentiality.

Basic DNSSEC validation

Note: Further setup is required for your DNS lookups DNSSEC by default. See #Install a DNSSEC-aware validating recursive server and #Enable DNSSEC in specific software.

Installation

The drill tool can be used for basic DNSSEC validation. To use drill, install the ldns package.

Query with DNSSEC validation

Then to query with DNSSEC validation, use the -D flag:

$ drill -D example.com

Testing

As a test use the following domains, adding the -T flag, which traces from the rootservers down to the domain being resolved:

$ drill -DT sigfail.verteiltesysteme.net

The result should end with the following lines, indicating that the DNSSEC signature is bogus:

[B] sigfail.verteiltesysteme.net.       60      IN      A       134.91.78.139
;; Error: Bogus DNSSEC signature
;;[S] self sig OK; [B] bogus; [T] trusted

Now to test a trusted signature:

$ drill -DT sigok.verteiltesysteme.net

The result should end with the following lines, indicating the signature is trusted:

[T] sigok.verteiltesysteme.net. 60      IN      A       134.91.78.139
;;[S] self sig OK; [B] bogus; [T] trusted

Install a DNSSEC-aware validating recursive server

To use DNSSEC system-wide, you can use a validating recursive resolver that is DNSSEC-aware, so that all DNS lookups go through the recursive resolver. BIND and unbound are two options that you can setup. Note that each requires specific options to enable their DNSSEC validation feature.

If you attempt to visit a site with a bogus (spoofed) IP address, the validing resolver (i.e., BIND or unbound) will prevent you from receiving the invalid DNS data and your browser (or other application) will be told there is no such host. Since all DNS lookups go through the validing resolver, you do not need software that has DNSSEC support built-in when using this option.

Enable DNSSEC in specific software

If not you choose not to #Install a DNSSEC-aware validating recursive server, you need to use software that has DNSSEC support builtin in order to use its features. Often this means you must patch the software yourself. A list of several patched applications is found here. Additionally some web browsers have extensions or add-ons that can be installed to implement DNSSEC without patching the program.

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