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seen Oct 14 at 5:17

Sep
6
comment How terribly flawed is this design for key storage?
Interesting, I'm currently working on a very similar project. To compare, I use scrypt with a 5 second/2GB work factor, AES-CBC using a 32 byte completely random key stored in a keyfile which is itself encrypted with the user's password.
Aug
22
awarded  Editor
Aug
22
revised How resilient to attackers with extreme resources available is this encryption method?
Specified various points.
Aug
21
awarded  Commentator
Aug
21
comment How can I accomplish Key Derivation in JavaScript?
He stated in his question that he knows he is dealing only with modern browsers so compatibility of window.getRandomValues shouldn't be a problem.
Aug
21
comment How resilient to attackers with extreme resources available is this encryption method?
If i'm utilizing truly random keys, how can I insert the user's password/passphrase into this equation? If I do the obvious thing and encrypt the random key with the scrypted password I'm back at where I started as long as the encrypted random bytes are distributed alongside the ciphertext. Could a scheme where the encrypted random bytes are saved as a secondary authentication mechanism work? This splits them from the ciphertext at the least and If I make the true encryption key the hash of the password concatted with the random bytes... could that work?
Aug
20
comment How resilient to attackers with extreme resources available is this encryption method?
Okay, now I have a better idea of what you are talking about. Could you perhaps point me towards an example/explanation of such a key derivation scheme? It sounds interesting but I'd need more info to see if it is even possible to implement using the environment I have access to.
Aug
20
comment How resilient to attackers with extreme resources available is this encryption method?
Sorry, I mixed nonce and iv together. I meant that CBC needs the random IV and that scrypt is the one that requires the nonce. A random key transferred using a key exchange system? I'm not sure I'm on quite the same page as you. Scrypt is used to derive a key from a user.
Aug
20
answered How can I accomplish Key Derivation in JavaScript?
Aug
20
comment How resilient to attackers with extreme resources available is this encryption method?
At that point the key really doesn't need to be pushed any further by my reckoning. I'm already using scrypt at a very decent work factor to derive the initial key so the usage of SHA-512 is just to ensure a difference between the aes and HMAC keys. The nonces are required by scrypt and CBC mode so I really can't remove them. Could you perhaps link me to an explanation of such a scheme?
Aug
20
awarded  Custodian
Aug
20
reviewed Approve suggested edit on How resilient to attackers with extreme resources available is this encryption method?
Aug
20
asked How resilient to attackers with extreme resources available is this encryption method?
Aug
19
accepted Can padding length, and thus plaintext length, be considered public information when using aes-cbc?
Aug
14
comment Can padding length, and thus plaintext length, be considered public information when using aes-cbc?
Alright, I'll make use of PKCS7. It looks much more foolproof and actually significantly reduces the complexity of the crypto code.
Aug
13
comment Can padding length, and thus plaintext length, be considered public information when using aes-cbc?
Yes, I am. I should've mentioned that padding length is a single byte in a ciphertext that looks like this:nonce | iv | cipherText | paddingeLegnth | HMAC
Aug
13
asked Can padding length, and thus plaintext length, be considered public information when using aes-cbc?
Jul
17
awarded  Teacher
Jul
17
answered How can scrypt be improved to counter GPU mining
Jul
16
awarded  Supporter