Suggestion: Multiple address creation from a single passphrase

[RobKohr]

It would be great if instead of creating just one address, you could bulk create a large set of addresses (let's say you need a thousand for a website).

The first one would be created using scrypt like it is currently. The second one for speed would be the SHA256 of the first's private key. The third would be the SHA256 of the second, and so on...

Of course if one of the private key's were discovered, the remainder of the set would be easily obtainable.

Alternatively, lets say the single passphrase was "password". The first key would be generated by warpwallet('password'). The second would be warpwallet('password1')... etc.

This would make it so the private key being discovered for any individual address would not unlock the rest of the set. The downside is it might take a few hours to generate a few thousand addresses.

[malgorithms]

you should check out HD wallets. In particular: https://github.com/bitcoin/bips/blob/master/bip-0032.mediawiki

we've talked about doing something like this with warp wallet, although we're pretty busy with Keybase right now. So for at least the short term, warp is staying as a single address. Still, you could use warp wallet as a library in software of your choice and generate a lot of them.

[gabridome]

+1 for BIP38 in Warp Wallet.
You should advice in that case that the entropy requested by the BIP is much stronger with the one achievable by a human generated passphrase:
"Generate a seed byte sequence S of a chosen length (between 128 and 512 bits; 256 bits is advised) from a (P)RNG." (https://github.com/bitcoin/bips/blob/master/bip-0032.mediawiki).
I personally think this is partially mitigated by the fact that the "seed stretching" warp wallet uses (scrypt + pbkdf2 +salt) is much stronger than a simple SHA512.

[lirazsiri]

Much stronger yes, but still vulnerable to attack for users choosing naive passphrases. Easy to make that mistake. With a salt, the economics change dramatically though, so Warpwallet should encourage that.