Determine the maximum level of rounds for some hardware given the maximum time that can be spent on login.
Using a fixed amount of time (and thus having an assured user experience) this module runs a couple of different bcrypt implementations so that the optimum number of rounds can be found given some hardware and the time that a login may take (i.e. Apple uses 80ms for unlocking).
Note: this package should be run on the target production hardware to get a good estimate.
The following packages are currently tested:
- bcrypt-nodejs (pure js, no deps)
- twin-bcrypt (pure js, no deps, asm.js)
- bcryptjs (pure js, no deps)
- bcrypt (c++, has deps)
Any suggestions on other bcrypt implementations are welcome.
Remember, even MD4 would be sufficient when using a strong password, so consider using a Diceware passphrase.
$ node bcrypt-speed.js [maxtime]
A maxtime is optional and defaults to 100ms. This should be the maximum time you want to let your users wait while you're verifying their password.
Example run on a 3 GHz core:
$ node bcrypt-speed.js test duration per number of rounds, up to 100ms bcrypt-nodejs (pure js, no deps) rounds ms 4 8 5 9 6 15 7 31 8 53 9 108 twin-bcrypt (pure js, no deps, asm.js) rounds ms 4 8 5 7 6 12 7 26 8 48 9 92 10 184 bcryptjs (pure js, no deps) rounds ms 4 9 5 8 6 16 7 32 8 57 9 114 bcrypt (c++, has deps) rounds ms 4 1 5 3 6 5 7 9 8 18 9 38 10 76 11 150
Discussion about bcrypt, password cracking speed and Diceware passphrases:
Copyright (c) 2014, 2015 Tim Kuijsten
Permission to use, copy, modify, and/or distribute this software for any purpose with or without fee is hereby granted, provided that the above copyright notice and this permission notice appear in all copies.
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