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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 suggested edit on hybrid tag wiki excerpt
Nov
28
reviewed Approve suggested edit on md2 tag wiki excerpt
Nov
28
reviewed Approve suggested edit on hybrid tag wiki
Nov
28
reviewed Approve suggested edit on
Nov
28
reviewed Approve suggested edit on access-control tag wiki
Nov
28
reviewed Approve suggested edit on constants tag wiki excerpt
Nov
28
reviewed Approve suggested edit on access-control tag wiki excerpt
Nov
28
reviewed Approve suggested edit on md2 tag wiki
Nov
28
reviewed Approve suggested edit on constants tag wiki
Nov
28
reviewed Approve suggested edit on
Nov
28
comment Design requirements for a keyed hash function?
The hash function needs to collision resistant. The encryption is trickier. Authenticated encryption always works (but that's a bit of cheating). An unauthenticated stream cipher does not work. A raw blockcipher with same block size as the hash does work.
Nov
28
comment Design requirements for a keyed hash function?
Related question: Is the encryption of a hash a good MAC?
Nov
28
comment Convert a number to sha-1
Searching a fixed 44 bit space might actually be one of the rare situations where a rainbow table is useful.
Nov
28
comment TCR hash functions from MD5
MD5 being broken only means that an attacker can find collisions when its used without a key.
Nov
27
reviewed Approve suggested edit on The exact definition of a symmetric encryption
Nov
27
comment scrypt and bcrypt for benefits of both?
For bcrypt and PBKDF2 combining them with each having have the work factor wouldn't really matter. For scrypt it's different: If you're CPU and not memory bound (typical for server side hashing), doubling the time budget doubles the used memory as well, making it four times as hard to break. => scrypt benefits from being the only function you use
Nov
27
comment Reusing PGP key when generating SSL Certificate Authority?
The problem with that is that you need to analyze all protocols using a key checking them for interactions. So I recommend against reusing a key like that.
Nov
26
comment How can Shamir's method for secret sharing work in the GF(256)?
Yes, there is no GF(6) since you can't write it as p^n.
Nov
26
answered How can Shamir's method for secret sharing work in the GF(256)?