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bio website github.com/CodesInChaos
location Frankfurt, Germany
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visits member for 3 years, 5 months
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Dec
3
reviewed Approve IV's from Crypto++ AutoSeededRNG always ends the same: Problem with the PRNG?
Dec
3
comment Using the same RSA keypair to sign and encrypt
Depends on tricky details of the padding scheme you use and your implementation. It'd generally discouraged to reuse keys like that.
Dec
3
comment What is the chance of a collision when using SHA-3?
1) There is no SHA-3 yet. Keccak has won the competition, but some details haven't been specified. 2) That depends on the output size, which you didn't specify. A hash outputs bytes, not characters. 3) Don't hash passwords with SHA-3. Use bcrypt, scrypt or PBKDF2 4) collisions have little relevance to password hashing, what matters is one-wayness or first pre-image resistance.
Dec
2
reviewed Approve IV's from Crypto++ AutoSeededRNG always ends the same: Problem with the PRNG?
Dec
2
revised Did NIST verify “post-quantum” claims in the SHA3 proposal papers?
added 227 characters in body
Dec
2
answered Did NIST verify “post-quantum” claims in the SHA3 proposal papers?
Dec
2
reviewed Approve Is this encryption scheme perfectly secure?
Dec
2
comment Did NIST verify “post-quantum” claims in the SHA3 proposal papers?
It's ignored because it isn't an attack against the algorithms themselves. It's an attack against the sloppy formulation of security claims in the papers describing those algorithms. Essentially they wrote security claims against classical computers without stating that these only apply to classical computers (which is obvious to any cryptographer). I suspect this is just a product of DJB being pissed that NIST insisted $2^n$ preimage resistance, which cubehash couldn't offer with acceptable performance. Ironically they wanted to lift that requirement after keccak won.
Dec
2
comment What is the function of the secret key “r” in Poly1305?
$r$ being secret is essential. The only point of $s$ is to prevent an attacker from learning $r$.
Nov
30
comment Why is Lamport-Diffie secure?
As far as we know, there there are collision resistant hashes (if necessary we can even weaken that to random prefix collision resistance) which resist quantum computers with slightly larger security parameter.
Nov
29
comment are ideal hashes possible to create?
If your definition of "ideal hash" is that it has no collisions with an input larger than the output, that's impossible. Pigeonhole principle
Nov
28
comment Convert a number to sha-1
I don't get your point regarding collisions. But 2^44 should be feasible as a one-time effort, the rainbow table is only used to make additional conversions cheaper.
Nov
28
reviewed Approve hybrid tag wiki excerpt
Nov
28
reviewed Approve md2 tag wiki excerpt
Nov
28
reviewed Approve hybrid tag wiki
Nov
28
reviewed Approve
Nov
28
reviewed Approve access-control tag wiki
Nov
28
reviewed Approve constants tag wiki excerpt
Nov
28
reviewed Approve access-control tag wiki excerpt
Nov
28
reviewed Approve md2 tag wiki