2,230 reputation
423
bio website touset.org
location San Francisco, CA
age 30
visits member for 1 year, 9 months
seen 20 hours ago

Cyclist. Rubyist.


May
9
reviewed No Action Needed Cryptographically secure keyed rolling hash function
May
9
reviewed Close Open source implementations of Symmetric Searchable Encryption and Order Preserving Encryption
May
7
awarded  Custodian
May
7
comment When is it safe to not use authenticated encryption?
Long story short, when your threat model does not include an attacker with the ability to manipulate ciphertexts prior to decryption.
May
6
reviewed Leave Open What informal indicators exist for estimating the computational infeasibility of cryptographic problems?
May
5
reviewed Looks OK Time Capsule cryptography?
May
5
reviewed Looks OK Question about dual system encryption
May
5
comment How do I produce a stream of secure random numbers from AES-Counter mode?
"So I know I have done it properly." As long as you're only considering an extremely narrow definition of "properly" that discounts timing attacks, paging virtual memory containing secrets to disk, buffer overflows, and other similar implementation faults. Producing the correct output isn't the only thing required of a cipher implementation.
May
1
comment PRF and hash functions
You should not be using a PRF to create secret keys. You should be using an RNG or CSPRNG, which may be built out of a PRG.
May
1
comment Accelerated hashing on consumer-grade CPU?
BLAKE2b is about as close as you can get to a modern hashing algorithm that's CPU-accelerated.
Apr
30
awarded  Custodian
Apr
30
reviewed Reopen Pseudocode for constant time modular exponentiation
Apr
30
reviewed No Action Needed Relative security of a Vigenère cipher
Apr
30
reviewed Close how to use salt to sign a message and how is it effective?
Apr
30
reviewed Leave Open An example of Knapsack Cryptosystem cracks/attacks?
Apr
30
awarded  Custodian
Apr
30
reviewed Leave Open How do you test the security of your cipher?
Apr
30
comment How do you test the security of your cipher?
Sorry, I figured it was obvious through context. It's true though that he won't receive a notification without addressing him directly.
Apr
30
comment How do you test the security of your cipher?
An implementation of a cipher is a different beast entirely. Even assuming a cipher with mathematically proven properties, any implementation itself is virtually guaranteed to be imperfect. Not just that it may have weaknesses (e.g., timing attacks) or bugs (e.g., overflows), but also problems with how it's used (e.g., does it mlock() memory to avoid swapping? Does it clear memory of secrets as soon as possible?
Apr
30
comment How do you test the security of your cipher?
You have professional cryptographers be unsuccessful at breaking it over the course of several years.