Scrypt hash required for Firebase is not the Scrypt hash Auth0 has implemented

[sosmani]

This has been asked in the community previously and erroneously assumed that Auth0 since now supports Scrypt algorithm - Firebase users can be seamlessly imported without requiring password changes.

Support for scrypt hash algorithm when importing users?

However, that is not the case Firebase uses a modified version of Scrypt

So seamless import in this manner is not possible. A possible solution is to use custom database and write your own Scrypt hash matching using now open sourced Firebase Scrypt library.

[dtsbg]

Did you happen to find a solution to this? I’m running into the same problems and not sure the best way around this.

[sosmani]

Yes there is a solution. The solution is to do this:

1. Export out all the Firebase user password hash and salt from the database.
2. Then use Firebase Scrypt algorithm in the get_user script to validate (Firebase has open sourced the scrypt algo) firebase-scrypt - npm

And if the user successfully logins using the database connection they will get imported and become Auth0 users (Migration will look seamless)

[dtsbg]

Appreciate the response on this. This would only work for a “Drip” migration as the users login but not for a “Bulk” migration, correct?

[sosmani]

That is correct. And that is your best bet as of now. There is no straight forward way unless Auth0 team moved in and creates a bulk mapping of email / salt / hash and then bakes in Firebase Scrypt. This may run afoul regulations also. Who knows?