Reputation
36,340
Next tag badge:
99/100 score
20/20 answers
Badges
2 56 151
Newest
 Good Answer
Impact
~633k people reached

15h
revised Should RSA primes p and q differ in length by “a few digits”?
Polish
16h
revised Should RSA primes p and q differ in length by “a few digits”?
Polish
16h
revised Should RSA primes p and q differ in length by “a few digits”?
Polish
16h
revised Should RSA primes p and q differ in length by “a few digits”?
Polish
16h
revised Should RSA primes p and q differ in length by “a few digits”?
Polish
16h
revised Should RSA primes p and q differ in length by “a few digits”?
Polish
17h
revised Should RSA primes p and q differ in length by “a few digits”?
Actually answer the question
17h
answered Should RSA primes p and q differ in length by “a few digits”?
23h
comment Should RSA primes p and q differ in length by “a few digits”?
FIPS 186-4 appendix B.3 still mandates safe primes for 1024-bit moduli (not 2048-bit); arguably, that is justified if you consider an adversary content with factoring any public moduli among many (like, to impersonate any member of a group): trying Polard's p-1 on all keys is a reasonable strategy, compared to attacking a single key with GNFS (the number of target public keys to make that workable is in the billions, I believe)
23h
reviewed Approve pairings tag wiki
23h
reviewed Approve Proving knowledge of a preimage of a hash without disclosing it?
1d
reviewed Approve Is it possible to enumerate the possible RSA keys?
1d
comment Is it possible to enumerate the possible RSA keys?
In addition of otus' comment: for compression of an RSA public key, see this. Compression is not the same as enumeration.
2d
comment Is a PRF applied to a secure MAC also a secure MAC?
One needs some condition on the PRF's input and output size; otherwise, a PRF applied to a secure MAC could well be a much less secure MAC than the original MAC is. Even if the PRF's input and output are the MAC's output size, odds of forgery by reusing a former MAC value are slightly better for the resulting MAC than they are for the original MAC.
May
2
awarded  Good Answer
Apr
27
revised Tackling encryption problems with “Zipf's law”?
Polish
Apr
26
revised Key size for HMAC-SHA256
Polish
Apr
26
revised Key size for HMAC-SHA256
mentionb performance for 64-byte key; remove duplicate definition of full-entropy
Apr
26
comment Key size for HMAC-SHA256
@Ralph P: That seems to make sense. The weakest links are likely to be the quality of the password combined with the entropy-stretching of PBKDF2 (which is far from being the best entropy-stretching function around), the ability of the user to recognize where s/he can safely type the password, and the integrity of the device used to process the password; any of these will be incomparably weaker than 256-bit.
Apr
26
revised Key size for HMAC-SHA256
typo