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I am a math/computer nerd. Nothing to see here, move along.


Jul
22
reviewed Approve suggested edit on How do we operate IV+1?
Jul
21
comment Lowest number challenge scheme
This is Yao's Millionaires' Problem: en.wikipedia.org/wiki/Yao's_Millionaires'_Problem
Jul
3
answered Pseudorandom permutations on domains of arbitrary (i.e. not a power of 2) size
Jun
19
reviewed Approve suggested edit on Modes of Operations Exercise
May
28
comment AES/CBC fixed Initial vector use-case
Using a fixed IV will also leak the information about the length of any shared prefixes. Also note that CBC won't stop someone from tampering with the cookie so that it decrypts to something that you don't expect, and if an attacker can guess at some of the cookie's contents, he will have a degree of control over what this is.
May
27
awarded  Enlightened
May
27
awarded  Nice Answer
May
24
awarded  Enlightened
May
24
awarded  Nice Answer
May
22
comment Can you determine an unknown value when it is combined with a known value and you are given the resulting hash?
If this is motivated by a homework question asking about the security of H(K|M) as a MAC (for hash function H, key K, and message M), you should consider the possibility that an attacker may not need to learn K in order to produce a forgery. Think about how SHA256 works internally.
May
22
comment Simple way to extend AES to 256-bit block size
possible duplicate of Is it possible to construct a secure block cipher of size $2n$ given a secure block cipher of size $n$?
May
20
awarded  Nice Answer
May
17
reviewed Approve suggested edit on tea tag wiki excerpt
May
16
answered Why do “nothing up my sleeve numbers” have low entropy?
May
15
reviewed Reject suggested edit on Is it possible to construct a secure block cipher of size $2n$ given a secure block cipher of size $n$?
May
15
answered Is it possible to construct a secure block cipher of size $2n$ given a secure block cipher of size $n$?
May
15
revised modulo operations in crypto algorithms
added 137 characters in body
May
15
revised modulo operations in crypto algorithms
Changed mathematical expressions to LaTeX.
May
15
answered modulo operations in crypto algorithms
May
4
revised How do I produce a stream of secure random numbers from AES-Counter mode?
added 96 characters in body; added 8 characters in body