813 reputation
324
bio website en.wikipedia.org/wiki/…
location United Kingdom
age 26
visits member for 3 years
seen Oct 20 at 16:03

Pentester, ex-developer, security researcher, reverse engineer, electronics tinkerer, internet activist, zombie eradicator, promulgator of useless facts, shrubbery inspector, bacon aficionado.

Strengths: Security, Crypto, Win32 API, C#, .NET, PHP, x86 assembly

All answers and comments are encrypted with ROT256-ECB.

Opinions are my own. Advice provided with no warranty.


Nov
29
comment What cipher mode is suitable for independantly decryptable short messages?
@IlmariKaronen Ah, that makes sense. I was erroneously considering each packet as a block.
Nov
29
comment What cipher mode is suitable for independantly decryptable short messages?
@IlmariKaronen Hmmm, is there a reason why Wikipedia describes CBC as using the previous ciphertext block? I can see that a single unique IV should be used for the conversation (i.e. the full stream of blocks), but not per-block.
Nov
29
comment What cipher mode is suitable for independantly decryptable short messages?
@CodesInChaos I'm aware, though the compressed data is a constant size per packet. I think the packets-vs-time domain is where side channel leaks are likely to occur, which I'll have to research further in order to discover a solution.
Nov
29
comment What cipher mode is suitable for independantly decryptable short messages?
Won't CBC require the previous ciphertext block, therefore making one lost packet destroy the next?
Nov
29
comment What cipher mode is suitable for independantly decryptable short messages?
CTR looks like it could do the job. Yes, integrity will be required. I was thinking of using a MAC, but if you know of a better solution I'm all ears! :)
Nov
28
accepted Memory-hard operations in work-factor hash functions
Nov
28
accepted Is it possible to ensure security with zero pre-shared information?
Nov
28
accepted Blum Blum Shub vs. AES-CTR or other CSPRNGs
Nov
28
asked What cipher mode is suitable for independantly decryptable short messages?
Nov
23
awarded  Yearling
Nov
6
comment Attack by replaying messages
Assuming, of course, both parties have a way of accurately measuring the time and compensating for geographical differences, daylight savings, leap-seconds, etc.
Nov
6
awarded  Critic
Oct
26
comment Is this a secure implementation of password reset email?
@JeremyW.Sherman The salt is allowed to be public. It's only there to prevent cross-user precomputation attacks such as rainbow tables.
Oct
16
awarded  Nice Question
Oct
12
accepted In layman's terms, how does Shor's algorithm work?
Oct
10
comment How is it possible to parallelize a hashing function to crack an iteratively hashed password?
An important point to make is that a GPU is essentially a large parallel arithmetic unit. Think of it as a 256-core (or more) CPU with little/no ability to do branching (if/then/else), but a particularly strong ability to perform scalar calculations. Most hash functions can be expressed almost entirely as a series of scalar calculations, which means that it's possible to use a GPU to perform lots of them at once.
Oct
10
comment Avalanche noise RNG for one-time pad use
Avalanche noise isn't particularly invulnerable to external EM, either. With a decent antenna and some maths you can skew the generator, or at least disrupt the quality of the random source. If you're looking at NESSIE spec security or similar, an attacker with physical proximity to the device should most definitely be considered a potential threat.
Oct
10
comment In layman's terms, how does Shor's algorithm work?
That's actually a really great way of explaining it.
Oct
6
comment In layman's terms, how does Shor's algorithm work?
@RickyDemer Maybe, but isn't the whole scary part that it can factor semiprimes in polynomial time, thus rendering a good portion of our current asymmetric ciphers broken?
Oct
3
comment Is 512-bit RSA still safe for signature generation?
@ThomasPornin Good point. I'll switch to 1024 for now, and I'll find a WinXP box to test 2048-bit on.