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11h
comment RSA private key confusion
This is off-topic. Hint: you've got $\phi(n)$ OK, but $d$ wrong; see the right method here. If you choose to compute $d=e^{-1}\bmod\phi(n)$ (there are other methods) then ensure that $d\cdot e\equiv1\pmod{\phi(n)}$, which currently does not hold. The ciphertext (that you note $m$) indeed is that for plaintext ma in big-endian ASCII (that you note $c$).
17h
comment RFC 5297 implementation
Was re-posted (in slightly better form) in this (off-topic) question.
17h
comment trying to get calculator and RSA calculatin does not make sense
First part (the only one close to being on-topic) is addressed in Calculating RSA private exponent
20h
comment Looking for a Javascript impementation of RFC 5297 (SIV)
Please close your other near-identical question. $\;$ Also, as is, the present question is off-topic (reference requests, especially for software, especially in a particular language, are excluded). It perhaps could become on-topic if you could expose what specific point you do not understand in RFC 5297.
21h
comment where can i learn the basics of AES?
I guess your primary reference should be AES Proposal: Rijndael. At a very high level, remember that the key schedule is here to build, from the key, one more (blockwide) subkey than there are rounds, because the block is XORed with a subkey on input, between rounds, and on output; and the subkeys should not be so closely related that it creates a weakness.
21h
revised RFC 5297 implementation
make the question visible
1d
comment Chinese Remainder Theorem and RSA with multiprime
The reference to PKCS, and the PKCS#11 tag, makes the question ambiguous. Is it specific to using a cryptographic token through the PKCS#11 interface? Or about the math of multiprime RSA? In the later case, the reference to PKCS is actually to PKCS#1v2, which includes provisions for multiprime RSA; not PKCS#11.
1d
revised Chinese Remainder Theorem and RSA with multiprime
improve text
1d
comment Energy necessary for brute-forcing or decryption
@Ricky Demer: According to the private key format, the public modulus is available in clear in the private key. A critical parameter is the value of the s2kcount parameter, which controls the work factor used for stretching of the passphrase. Depending on that, the point of least hardest attack is the passphrase, or the factorization of the public modulus. By default stretching used to hash about $2^{16}$ bytes, but I have read about plans to increase that.
2d
comment How can AES be considered secure when encrypting large files?
@kasperd: my $r$ is residual risk as a base-2 log, not comparable to the security of a key in bits (the adversary can use more brute force against the later, not former). When making a 100 miles trip by car in the US, one accepts a residual risk of death about $2^{-20}$, compare to $2^{-40}$ of being hacked; see also my consideration about oblivion by asteroid.
2d
revised SipHash - 64 bit (second) preimage security?
typo
2d
revised SipHash - 64 bit (second) preimage security?
Add conclusion
2d
revised SipHash - 64 bit (second) preimage security?
polish
2d
answered SipHash - 64 bit (second) preimage security?
2d
comment SipHash - 64 bit (second) preimage security?
Are you considering SipHash with the supposedly secret key gone public, making SipHash as hash, when normally SipHash is a MAC (aka Pseudo Random Function Family) rather than a hash (aka random public menber of a Pseudo Random Function Family) ?
2d
comment How can AES be considered secure when encrypting large files?
@kasperd: your rule of thumb is way overly conservative; CBC/CFB modes are good for $b\cdot2^{(b+1-r)/2}$ bits where residual odds of duplication of one block are $2^{-r}$. With AES and $r=40$ (residual odds of one in a million millions, entirely negligible compared to oblivion by asteroid on any given day) that's 3 petabit (nearly 400 terabyte). CTR/OFB modes are good for even more.
May
1
comment Is it safe to derive two different keys with the same password and key derivation function using two different salts?
@rossum: your appendix is to belt what salt+KDF are to suspenders.
May
1
comment If a DES key correctly decrypts one message, what's the probability it's the real key?
Hint: if DES was an ideal cipher, $X\to DES_X(M)$ would behave like a random function, Using this, estimate odds that there exists no $T$ less than $K$, as a function of the value of $K$; then that expected odd for random $K$; then what's asked.
May
1
revised Can I use the output from a DRBG directly as K for AES, or do I need to use a key generator algorithm?
Add reference to draft NIST SP 800-90B
May
1
revised Can I use the output from a DRBG directly as K for AES, or do I need to use a key generator algorithm?
typo