2,295 reputation
211
bio website
location
age
visits member for 1 year, 2 months
seen 14 hours ago

Apr
13
reviewed Approve suggested edit on knapsack tag wiki excerpt
Apr
6
comment Secure AES Key Generation via Salsa20?
Is there a specific reason that the output of /dev/urandom is not sufficient to be used as an AES key directly?
Apr
6
comment Game with symmetric key
Outside the rules of the game, a player may engage fraudulent activities (side-channel). For instance, Bob may have installed webcam at Alice's and therefore know all Alice's choices in advance.
Apr
5
awarded  Enthusiast
Apr
2
comment How do I create a short signature? (e.g. less than 100 bytes)
Some variants of Merkle Signature Scheme allow small signatures (around 256 bits for 128 bit security), though public key is pretty large. This means the signature length will be pretty much the same than with BLS.
Mar
30
answered HKDF vs TLS PRF. Which of the one is better?
Mar
27
answered Can CBC encryption have separate keys for separate blocks of plain text?
Mar
25
revised Is PBKDF2-HMAC-SHA1 really broken?
clear answer
Mar
25
comment Is PBKDF2-HMAC-SHA1 really broken?
These collisions are relatively rare. If bruteforce attacker needs to go through $499999999$ passwords instead of $500000000$ it does not affect the time for brute forcing significantly.
Mar
25
answered Is PBKDF2-HMAC-SHA1 really broken?
Mar
22
comment SHA-224 Purpose
I find your answer most insightful this far. The SHA-224 was apparently primarily specified for DSS (ECDSA, DSA, RSA). But for all these uses SHA-256 is at least as good. SHA-224 serves more to create confusion and one more option.
Mar
21
comment SHA-224 Purpose
FIPS 180's SHA-224 is somewhat endorsed for specific FIPS 186 ECDSA curve (P-224) and DSA domain param sizes (L=2048, N=224). However, NIST P-224 curve predates the FIPS 180-2 change notice 1, and for that reason, several systems have already taken it into use with other SHA family hashes.
Mar
21
revised SHA-224 Purpose
Text said FIPS 186-x (DSS), but it obviously meant FIPS 180 (SHS), especially as the link pointed to FIPS 180 document.
Mar
17
comment Randomness test question from FIPS 140-1 and comparison with 140-2
@fgrieu: Not neccessarily pointless. It can be e.g. that recovery requires full self health testing procedure, which can ensure that the test failure was due to random event (which occurs once in a while) rather than a true failure of the entropy source (or DRBG).
Mar
17
answered Randomness test question from FIPS 140-1 and comparison with 140-2
Mar
17
comment Randomness test question from FIPS 140-1 and comparison with 140-2
I believe that in some cases it is not necessary to recover error state resulting from FIPS 140-2 test failure manually in case the error was not a hard error.
Mar
16
answered Question on RSA trapdoor permutation
Mar
16
comment Question on RSA trapdoor permutation
To answer the question a better specification of meaning of single computer (is it one from top 500 list or $300 bargain pc) and is quantum computer something that is not publicly available or is it e.g. D-Wave Two?
Mar
15
answered Reusing AES-CTR Keys and IVs for File Encryption
Mar
15
comment KCV and compatibility with block cipher modes of operation
Thank you for the link and abstract. The paper contains useful information regarding the subject.