The Cloudflare TLS 1.3 beta is run by a Go implementation of the protocol based on the Go standard library, crypto/tls. Starting from that excellent Go codebase allowed us to quickly start experimenting, to be the first wide server deployment of the protocol, and to effectively track the
TLS 1.3 explained by the Cloudflare Crypto Team at 33c3
Nick Sullivan and I gave a talk about TLS 1.3 at 33c3, the latest Chaos Communication Congress. The congress, attended by more that 13,000 hackers in Hamburg, has been one of the hallmark events of the security community for more than 30 years. You can watch the recording
So you want to expose Go on the Internet
This piece was originally written for the Gopher Academy advent series. We are grateful to them for allowing us to republish it here. Back when crypto/tls was slow and net/http young, the general wisdom was to always put Go servers behind a reverse proxy like NGINX. That's not
Dyn issues affecting joint customers
Today there is an ongoing, large scale Denial-of-Service attack directed against Dyn DNS. While Cloudflare services are operating normally, if you are using both Cloudflare and Dyn services, your website may be affected. Specifically, if you are using CNAME records which point to a zone hosted on Dyn, our DNS
TLS nonce-nse
One of the base principles of cryptography is that you can't just encrypt multiple messages with the same key. At the very least, what will happen is that two messages that have identical plaintext will also have identical ciphertext, which is a dangerous leak. (This is similar to why you
An overview of TLS 1.3 and Q&A
The CloudFlare London office hosts weekly internal Tech Talks (with free lunch picked by the speaker). My recent one was an explanation of the latest version of TLS, 1.3, how it works and why it's faster and safer. You can watch the complete talk below or just read my
The complete guide to Go net/http timeouts
When writing an HTTP server or client in Go, timeouts are amongst the easiest and most subtle things to get wrong: there’s many to choose from, and a mistake can have no consequences for a long time, until the network glitches and the process hangs. HTTP is a complex
Yet Another Padding Oracle in OpenSSL CBC Ciphersuites
Yesterday a new vulnerability has been announced in OpenSSL/LibreSSL. A padding oracle in CBC mode decryption, to be precise. Just like Lucky13. Actually, it’s in the code that fixes Lucky13. It was found by Juraj Somorovsky using a tool he developed called TLS-Attacker. Like in the “old days”