On Opportunistic Encryption
Opportunistic encryption has become quite a hot topic recently, and blew up in a big way thanks to an Internet Draft that was published on February 14th for what amounts to sanctioned man-in-the-middle. Privacy advocates were quickly up in arms – but it’s not that simple (see here). As pointed out by Brad Hill, this isn’t about HTTPS traffic, but HTTP traffic using unauthenticated TLS; thanks to poor wording in the document, it’s easy to miss that fact if you just skim it.
Read more…Worried about the NSA? Try AES-512!
…or, The Cost of Wild Speculation. “We need to boost our security – I think the NSA has broken everything we use. AES-256 is too weak, I don’t trust it. Find a way to implement AES-512.” Double-AES-256! It’d be easy, and double encrypting has never bitten us before. So, let’s write some code! def encrypt(msg, iv, key) return e(e(msg, iv, key.slice(0..31)), iv, key.slice(32..63)) end def decrypt(cipher, iv, key) return d(d(cipher, iv, key.
Read more…Crypto, the NSA, and Broken Trust
Even as a child I was fascinated by cryptography – and often left the local librarians with puzzled looks thanks to the books I would check out. It’s so elegantly simple, and yet massively complex. There is one very unusual property of crypto though – it’s not about math or modes, it’s about trust. Cryptography, especially as used today, has the most wonderful dichotomy of trust; on one hand crypto, by its very nature, is used in situations lacking trust.
Read more…Hash Storage: Make Attackers Work
So you hash your passwords? Good. Do you salt? That’s good. Do you use a strong hashing algorithm (PBKDF2/bcrypt/scrypt)? Great! But how do you store the hashes? What happens when you get hit with a SQL injection attack? I’m a big believer in defense in-depth – not that marketing garbage about stacking layers of blinky-light boxes, but using techniques to add extra work for an attacker. You might not be able to stop every attack, but the more work they have to do, the better the odds they won’t get everything they want.
Read more…OPSEC, The NSA, and You
It’s been two weeks since news broke about the NSA collecting massive amounts of data from Verizon; and likely everybody else. There’s also PRISM – whatever the hell that is – it seems there’s no agreement on that, and I doubt there will be anytime soon. What really matters here though, is we have proof that people are watching – and if it’s happening in the US, it’s probably happening everywhere else.
Read more…Password Hashing: No Silver Bullets
In the dark days of the web, if a service hashed your password instead of storing it in plain text, they were doing good. As sites were hacked, and credentials stolen, a silver bullet emerged: always hash and salt passwords when storing them. Many, many services were built with this design – LivingSocial is a great example. SHA1 hashing with a 40 byte salt – once upon a time, that was considered reasonable protection.
Read more…First, Do No Harm: Developers & Bad APIs
Primum non nocere (first, do no harm) – an iconic phrase in modern medicine, yet also applicable to many other fields. This is something I wish more people would think about, developers especially – and primarily when writing new APIs. In general, developers don’t have an impressive history with security – quite frankly, developers suck. Seeing as I consider myself a developer, that’s painful to admit. Chris Andrè Dale posted an interesting article some time ago that got me thinking: Why it’s easy being a hacker: A SQL injection case study – Chris pointed out the problems with educational material that developers are using, and just how bad the examples are.
Read more…Piracy is not Theft
For many years now groups like the MPAA and RIAA have tried to convince the public that piracy (that is, copyright infringement) is theft – and many people have come to believe this, but it’s not true. In reality, copyright infringement is far more analogous to trespassing than it is to theft in its core concepts – and even moreso in the digital world. To make it clear, I am looking at this from a largely historical perspective, looking at the origins of copyright and how it was intended to be used.
Read more…You can’t fix stupid…
For those outside of the IT field, developers are looked at as miracle workers – through us, business leaders think anything is possible (and they often see no reason why we can’t work our latest miracle by the next morning). In reality though, we do work miracles; we save companies vast amounts of money every year through increased worker efficiency and automation, we enable new lines of business that wouldn’t be possible otherwise, and reduce energy costs because we keep the office lights turned off.
Read more…What’s your Code Legacy?
When you move on to your next challenge how will those that inherit your code think of you? Noble or notorious, innovator or insane? This is a question that all developers should ask themselves frequently; though too few ever do. You should always write with the assumption that someday a new developer will take over your code, and they will question every decision and assumption you’ve made. When this happens, what will they think of you?
Read more…
About Me
Security researcher, engineer and software developer with more than 20 years of experience.
Work: I primarily focus on application security, usable security, secure communications, and cryptography. I build and lead strong and dynamic teams, who cover all facets of security and privacy.
Writing: I write about my research, security in general, development and software design, and leadership through my blog, essays, and various publications. I also engage in some creating writing when I can.
Photography: I am a purist fine art photographer, working primarily in black & white, and focused on sharing new perspectives of the world. Limited edition prints of my work are available on my online gallery. I also have a background in photojournalism, and volunteer in this field when I can.