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visits member for 3 years, 3 months
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I'm an engineer with experience in applied cryptography, in particular in Smart Card systems.


12h
comment Undrestanding hashing algorithm with MD5 in Javascript
The code that you posted appears to be MD5 for Javascript complete with workaround if (a + b) & 0xFFFFFFFF turns out to misbehave. Helping you with code is off-topic, discussing unspecified "other code" is even wilder.
15h
comment How Brittle Are LCG-Cracking Techniques?
Agreed, the quote is not the right one. Will try better at finding a justification of my vague memory that Donald Knuth has stepped back form the 1985 claim that you quote.
16h
comment Small Encryption Exponent
@codeomnitrix: I scratched my head and failed to see how Coppersmith's method (also here) could help in your other question as it originally stood; but the modified one is very different!
19h
comment How Brittle Are LCG-Cracking Techniques?
IIRC Donald Knuth has stepped back form the 1985 claim that you quote. In an errata to volume 2, he wrote "Lagged Fibonacci generators have been used successfully in many situations since 1958, so it came as shock to discover in the 1990s that they actually fail an extremely simple, non-contrived test for randomness".
21h
revised Maximum length in bits of the product n=pq
generalisation to product of odd primes
1d
comment RSA OAEP: prevention of partial decryption of ciphertexts
Quick hint: contrast to the scheme attacked in this reference, and its reference 2.
1d
revised Are there any digital signature algorithms in common use that result in 32-byte signatures?
remove repetiton, more explicit signature step 5
1d
revised Are there any digital signature algorithms in common use that result in 32-byte signatures?
fix that M' was used without definition; explicit size overhead.
1d
comment Minimum number of independent trials needed to detect a bias
That seems to be the correct order of magnitude. Statisticians have more precise evaluations, taking into account the confidence level that we want in the conclusions. We are talking about a Chi-squared test with one degree of freedom. There are also methods to decide dynamically if we can stop the test or continue, for given confidence levels or reaching the wrong conclusions.
1d
comment Maximum length in bits of the product n=pq
@cryptoclk: the maximum size indeed is 2048 bits; the answer I commented reaches the correct numeric answer to the question, but puts that in a formally incorrect statement (notice total is not the same as maximum).
1d
comment Maximum length in bits of the product n=pq
@pushpen.paul: NextPrime[2^1023]-2^1023 is 1555 according to WolframAlpha
1d
revised Are there any digital signature algorithms in common use that result in 32-byte signatures?
Add missing term at verification step 6
1d
revised Maximum length in bits of the product n=pq
Per request, explain how things are in practice.
1d
revised Are there any digital signature algorithms in common use that result in 32-byte signatures?
Fix RSA public key fuction in verification
1d
revised Are there any digital signature algorithms in common use that result in 32-byte signatures?
Give step-by-step description
1d
revised Maximum length in bits of the product n=pq
Full proof
1d
comment Maximum length in bits of the product n=pq
The assertion the total number of bits after multiplication will be 2*1024 is incorrect; counterexample: $p=q=2^{1023}+1155$.
1d
answered Maximum length in bits of the product n=pq
1d
revised simulating rc4-256 with rc4-128
point interesting comment
1d
revised Are there any digital signature algorithms in common use that result in 32-byte signatures?
Give mitigation to attacks on ISO/IEC 9796-2 scheme 1 with SHA-1