April 13, 2016 12:39 PM
What happened next: the deprecation of ANY
Almost a year ago, we announced that we were going to stop answering DNS ANY queries. We were prompted by a number of factors: The lack of legitimate ANY use. The abundance of malicious ANY use. The constant use of ANY queries in large DNS amplification DDoS attacks....
April 05, 2016 12:05 PM
The revenge of the listening sockets
Back in November we wrote a blog post about one latency spike. Today I'd like to share a continuation of that story. As it turns out, the misconfigured rmem setting wasn't the only source of added latency. It looked like Mr Wolf hadn't finished his job....
April 01, 2016 4:43 PM
Come Geek Out With The Original Inventor of DNS at CloudFlare
We like DNS, we think you might too. CloudFlare and Gandi are hosting a three-part series on DNS. Our first event will be at the CloudFlare office with Paul Mockapetris, the original inventor of the Domain Name System....
March 04, 2016 6:02 PM
A Deep Dive Into DNS Packet Sizes: Why Smaller Packet Sizes Keep The Internet Safe
One way that attackers DDoS websites is by repeatedly doing DNS lookups that have small queries, but large answers. The attackers spoof their IP address so that the DNS answers are sent to the server they are attacking, this is called a reflection attack....
February 29, 2016 1:42 PM
A tale of a DNS exploit: CVE-2015-7547
A buffer overflow error in GNU libc DNS stub resolver code was announced last week as CVE-2015-7547. While it doesn't have any nickname yet (last year's Ghost was more catchy), it is potentially disastrous....
January 19, 2016 6:19 PM
Go coverage with external tests
The Go test coverage implementation is quite ingenious: when asked to, the Go compiler will preprocess the source so that when each code portion is executed a bit is set in a coverage bitmap....
January 13, 2016 11:44 AM
Flexible, secure SSH with DNSSEC
If you read this blog on a regular basis, you probably use the little tool called SSH, especially its ubiquitous and most popular implementation OpenSSH....
November 10, 2015 1:56 PM
Announcing Universal DNSSEC: Secure DNS for Every Domain
CloudFlare launched just five years ago with the goal of building a better Internet. That’s why we are excited to announce that beginning today, anyone on CloudFlare can secure their traffic with DNSSEC in just one simple step....
October 29, 2015 9:26 PM
Creative foot-shooting with Go RWMutex
Hi, I'm Filippo and today I managed to surprise myself! (And not in a good way.) I'm developing a new module ("filter" as we call them) for RRDNS, CloudFlare's Go DNS server. ...