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2d
comment RSA: How effective is this keypair-trash attack
There is an even "more annoying scenario" than that: "compute the gcd of" each pair $\hspace{1.32 in}$ of "public keys you can scan over the net." $\;$
2d
answered How do I communicate the value of the initialization vector to the end user? Should it be part of the encrypted message?
2d
comment How do I communicate the value of the initialization vector to the end user? Should it be part of the encrypted message?
From the short description you gave of the assignment, it sounds like you don't need to implement a mode of operation. $\:$ For modes of operation (including CBC), you would store the initialization vector as the beginning of the ciphertext, so that the decryption algorithm can do what you describe. $\;\;\;\;$
2d
comment How do I communicate the value of the initialization vector to the end user? Should it be part of the encrypted message?
"to implement a 32-bit block cipher" for which a specification was given, or one chosen by you? $\hspace{.6 in}$ "a simple block-cipher that uses CBC" is possible, although it seems far more likely that you mean "CBC mode with a simple block cipher", especially since you then jump straight into talking about IVs. $\hspace{.6 in}$
Jan
28
comment Negative exponents in Shoup's threshold RSA?
x^(-n) = x^((-1)*n) = (x^(-1))^n $\;$
Jan
26
revised Crypto library that supports ElGamal PET and Mixnets
improved grammar
Jan
26
answered Will current encryption always remain secure? Is there mathematical proof?
Jan
26
comment Is it a variant of Strong RSA assumption?
What about just outputting $\:(c,\hspace{-0.04 in}1)\;$? $\;\;\;\;$
Jan
25
revised What is contained in a RSA key file?
fixed title's grammar
Jan
24
comment How much work is required to detect multiple collisions for a hash function?
detecting $\mapsto$ finding $\:$ ? $\;\;\;\;$
Jan
23
comment Simple message authentication code
Melab: $\;\;\;$ If "typical RSA signatures ... message's hash" aren't insecure, then that's because their hash functions are collision resistant. $\:$ For MACs, I am not aware of any reason to require collision resistance. $\;\;$
Jan
23
comment Simple message authentication code
@StephenTouset : $\:$ Melab didn't say that $E_k$ and $D_k$ would be with a block cipher. $\hspace{1.44 in}$
Jan
23
revised Finding strong primes
improved grammar
Jan
23
comment Simple message authentication code
The result that "every other friggin' message authentication code, digital signature scheme, and CSPRNG out there" "requires collision-resistance of the hash function." $\:$ Collision resistance is the problem, and I'm not aware of any practical implementations that would not necessary immediately fail when a hash collision is found, athough one can presumably avoid requiring collision resistance. $\:$
Jan
23
comment Security issues for integrating AAA and OTP services
"AAA" = ... $\;$
Jan
23
comment Simple message authentication code
(continued ...) $\:$ Also, what I believe is currently the best known security argument for HMAC only uses pseudorandomness of the compression function. $\;\;\;\;$
Jan
23
comment Simple message authentication code
My point is that I believe the result "so does every other friggin' message authentication code, digital signature scheme, and CSPRNG out there" would potentially be publishable, since those can be based on one-way functions, and from what I can find (section 4.3), there is currently no publicly known way to base collision-resistance on one-way functions. $\:$ (... continued) $\;\;\;\;$
Jan
23
comment Simple message authentication code
@Melab : $\:$ en.wikipedia.org/wiki/Universal_hashing $\;\;\;\;$
Jan
23
comment Simple message authentication code
That construction requires collision-resistance of the hash function. $\;$
Jan
20
revised Montgomery and Galois fields
general copy-editing