November 30, 2012 archive

What Happens When All Communication From A Country Is Disrupted?

What happens when all communications into and out of a country is completely disrupted? We're seeing that right now with Syria. As I wrote on CircleID yesterday, all Internet access is down... and reports say that all communication via cell phones and landlines has also been terminated.

What happens when a country just completely... drops... off...

It's scary, really, to think about. And we're seeing it play out right now. The links are still all down.

My thoughts are definitely with the people there in the country. I hope things are okay... and that the connections get restored soon.

Crazy times...

Hash-slinger Helps You Easily Create TLSA records for DNSSEC / DANE

If you are looking to get started with the DANE protocol to provide higher security for SSL/TLS certificates, a basic question can be – how do you generate a TLSA record to put in your DNS zone file?

As we outlined before, there are a number of different tools you can use.  One that is perhaps the simplest, though, is a package for Linux from Paul Wouters called “hash-slinger” that is available at:

http://people.redhat.com/pwouters/hash-slinger/

One of the tools provided in the package is a command “tlsa” which does exactly what you might think – generate the TLSA record!  Paul showed how easy it is:

$ tlsa --create ietf.org
No certificate specified on the commandline, attempting to retrieve it from the server ietf.org.
Attempting to get certificate from 64.170.98.30
Got a certificate with Subject: /O=*.ietf.org/OU=Domain Control Validated/CN=*.ietf.org
_443._tcp.ietf.org. IN TLSA 3 0 1 54f3fd877632a41c65b0ff4e50e254dd7d1873486231dc6cd5e9c1c1963d1e4e

That’s it!  Now you can copy that record to your DNS zone file and you will be in the business of publishing a TLSA record!

Well, okay, it might not be that simple.  If your nameserver or DNSSEC-signing tool doesn’t yet support the TLSA record (outlined in RFC 6698), you might need to add a “-o generic” flag onto the command line to get the appropriate record. And you might want to add on more options, as Shumon Huque did in his walk-through of setting up a TLSA record.

The key is that this tool is out there and can help all of us interested in getting the DANE protocol more widely deployed to start getting TLSA records more visible. Kudos to Paul for developing the tool and making it available.

If you use SSL/TLS on your sites, and you have your domain signed with DNSSEC, why not go the extra step and get a TLSA record out there?

Hash-slinger – a tool for creating TLSA records for the DANE protocol

Hash-slinger is a package of tools created by Paul Wouters of RedHat to make it easy to create records for  the DANE protocol that will allow you to secure your SSL/TLS certificates using DNSSEC.

The package is available for Linux at:

http://people.redhat.com/pwouters/hash-slinger/

One of the tools provided in the package is a command “tlsa” that generates TLSA records (outlined in RFC 6698). Paul Wouters showed how easy it is:

$ tlsa --create ietf.org
No certificate specified on the commandline, attempting to retrieve it from the server ietf.org.
Attempting to get certificate from 64.170.98.30
Got a certificate with Subject: /O=*.ietf.org/OU=Domain Control Validated/CN=*.ietf.org
_443._tcp.ietf.org. IN TLSA 3 0 1 54f3fd877632a41c65b0ff4e50e254dd7d1873486231dc6cd5e9c1c1963d1e4e

You can now copy that record to your DNS zone file and be in the business of publishing a TLSA record.

If your nameserver or DNSSEC-signing software does not yet support the TLSA RRtype defined in RFC 6698, you can create a “generic” record type:

$ tlsa --create -o generic ietf.org
No certificate specified on the commandline, attempting to retrieve it from the server ietf.org.
Attempting to get certificate from 64.170.98.30
Got a certificate with Subject: /O=*.ietf.org/OU=Domain Control Validated/CN=*.ietf.org
_443._tcp.ietf.org. IN TYPE52 \# 35 03000154f3fd877632a41c65b0ff4e50e254dd7d1873486231dc6cd5e9c1c1963d1e4e

The “tlsa” command also has other options for generating other types of TLSA records.