Minimal browser builds

[kumavis]

by supplying our own more minimal version of https://github.com/crypto-browserify/crypto-browserify
we can drop the following deps:

require('diffie-hellman')
require('browserify-sign')
require('create-ecdh')
require('public-encrypt')

bc we are only using

crypto.randomBytes
crypto.pbkdf2Sync
crypto.createCipheriv
crypto.createDecipheriv

we just need to make a more minimal crypto entrypoint https://github.com/crypto-browserify/crypto-browserify/blob/master/index.js
and sub it out with the browser field https://github.com/substack/node-browserify#browser-field

[chiro-hiro]

@kumavis I have tried to build my own browser version by using browserify. It's working damn slow.

[IstoraMandiri]

@tad88dev same experience; toV3 is taking around 20 seconds in Chromium

[axic]

@tad88dev @hitchcott I'm afraid that is an intentional parameter of using scrypt. The point of scrypt is to be CPU and memory hard. Using the C scrypt implementation it is >10 times faster though.

In the browser it should be run in a worker.

Alternatively you can try tweaking the scrypt parameters (https://github.com/ethereumjs/ethereumjs-wallet#remarks-about-tov3) with the risk of reducing security significantly. Some wallets (such as keythereum) use much lower iteration count and thus they are faster. etheruemjs-wallet uses the default settings used by geth.

[chiro-hiro]

@axic Agree, scrypt.js is slow down whole process. I have some "cheats" to speed up without change the scrypt parameters.
I have a table to lookup computed scrypt hash:
sha-256(x) ----> scrypt(x)

[IstoraMandiri]

Thanks @axic, the webworker solution should be good enough. Perhaps it's worth adding to the docs.

Perhaps even webworker could be used automatically if that feature is detected.

[connectdotz]

has this problem ever resolved? can this library actually run in the browser with reasonable performance? According to browserify:

Get browser versions of the node core libraries events, stream, path, url, assert, buffer, util, querystring, http, vm, and crypto when you require() them

Looks like the code is still using the node.js crypto, therefore wondering if this ever resolved?