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seen Jul 18 at 7:39

Dec
30
comment Random Number Generation with a Entropy pool versus Seed
@user4982 Thanks. I was unaware of the NIST specs.
Dec
30
comment Random Number Generation with a Entropy pool versus Seed
@Reid Thanks. I do already have this implemented but considering its really new I am deciding to back the RNG with something slightly better than Math.random as a fallback. I did look at SJCL but as I've already started porting, I will simply continue porting it. This was more of a side question :)
Dec
30
comment Random Number Generation with a Entropy pool versus Seed
@HenrickHellström The difference between a CSPRNG and a PRNG is simply that one can be predicted and one cannot. I may want to make a poker game where I do not wish to have the randomness predicted so a CSPRNG would be ideal.
Apr
8
comment Does the IV need to be known by AES (CBC mode)?
Ah ok, sorry, I thought you were referencing the image only. That would answer my question. Post it as an answer and I'll mark it as correct! Sorry for wasting your time -.-
Apr
8
comment Does the IV need to be known by AES (CBC mode)?
@StephenTouset but in decryption it doesn't actually use the IV at all for the actual cipher transformation, just for stripping it from the plaintext at the end.
Apr
8
comment Does the IV need to be known by AES (CBC mode)?
In fact that Wikipedia article confirms what I said. If the IV is the same length, and is prepended or appended to the plaintext, then you could simply strip those bytes off the end or from the front after decryption. The only reason the decryptor needs the IV (by the looks of that article) is to know what bytes to strip!
Apr
8
comment Does the IV need to be known by AES (CBC mode)?
I never understood exactly what CBC was doing tho. Did it take the unencrypted previous block as the IV for the next, or the encrypted previous block as the IV for the next?
Apr
8
comment AES encryption with shared IV
Paulo, I understand I asked this a while ago, but you mean I should use a different encryption key for each direction of packets?
Apr
5
comment How can mega store my login details and still be secure?
Patience really isn't an issue. I was thinking this at a more, FBI wants information, goes downloads encrypted files of suspect user, requests from mega their encrypted key and a hash of their password, FBI uses super duper mega powerful computer to bruteforce hash.
Apr
4
comment How can mega store my login details and still be secure?
Thanks for that :)
Apr
4
comment How can mega store my login details and still be secure?
The attacker would know when they have generated a password that matches the hash. I get the hash, and the salt. Then I bruteforce every combination until I get the hash stored in the database. Now I have password, I can simply decrypt the key used to encrypt all my files.
Apr
4
comment How can mega store my login details and still be secure?
Also, what do you mean by the password-hash and the symmetric password hash? Are they not the same thing?
Apr
4
comment How can mega store my login details and still be secure?
I'm assuming that the symmetric key being encrypted is a string of 16 or 32 pseudo-random bytes, so there's no way for an attacker to verify that they've decrypted the key successfully without actually attempting to decrypt your data with it In my opinion is wrong. Lets say they use MD5 as a hasing algo (I know, its not secure but meh). All I would need to do is bruteforce that MD5 and I would have the password used to encrypt my symmetric key.
Feb
17
comment AES encryption with shared IV
Forget that last comment. Of course the IV needs to be known, otherwise AES would be unable to "un-XOR" the message when decrypting.
Feb
17
comment AES encryption with shared IV
Thanks, your idea for the random number generator is a good one! I am using CBC mode so this sounds good. However I have a question, everywhere I read, it seems as if (at least to me) that the IV is not important in the decryption of the ciphertext. What I mean is, if I just use random crap for the IVs would this work or not? I've seen people using timestamps as IVs however how would you get that to the other end without sending it in the message?
Feb
17
comment AES encryption with shared IV
@Thomas When I say packet, I mean message.