mirror of
https://github.com/ergochat/ergo.git
synced 2024-11-30 16:09:26 +01:00
35 lines
1.3 KiB
Go
35 lines
1.3 KiB
Go
|
// Copyright (c) 2018 Shivaram Lingamneni
|
||
|
|
// released under the MIT license
|
||
|
|
|
||
|
|
package passwd
|
||
|
|
|
||
|
|
import "golang.org/x/crypto/bcrypt"
|
||
|
|
import "golang.org/x/crypto/sha3"
|
||
|
|
|
||
|
|
const (
|
||
|
|
MinCost = bcrypt.MinCost
|
||
|
|
DefaultCost = 12 // ballpark: 250 msec on a modern Intel CPU
|
||
|
|
)
|
||
|
|
|
||
|
|
// implements Dropbox's strategy of applying an initial pass of a "normal"
|
||
|
|
// (i.e., fast) cryptographically secure hash with 512 bits of output before
|
||
|
|
// applying bcrypt. This allows the use of, e.g., Diceware/XKCD-style passphrases
|
||
|
|
// that may be longer than the 80-character bcrypt limit.
|
||
|
|
// https://blogs.dropbox.com/tech/2016/09/how-dropbox-securely-stores-your-passwords/
|
||
|
|
|
||
|
|
// we are only using this for user-generated passwords, as opposed to the server
|
||
|
|
// and operator passwords that are hashed by `oragono genpasswd` and then
|
||
|
|
// hard-coded by the server admins into the config file, to avoid breaking
|
||
|
|
// backwards compatibility (since we can't upgrade the config file on the fly
|
||
|
|
// the way we can with the database).
|
||
|
|
|
||
|
|
func GenerateFromPassword(password []byte, cost int) (result []byte, err error) {
|
||
|
|
sum := sha3.Sum512(password)
|
||
|
|
return bcrypt.GenerateFromPassword(sum[:], cost)
|
||
|
|
}
|
||
|
|
|
||
|
|
func CompareHashAndPassword(hashedPassword, password []byte) error {
|
||
|
|
sum := sha3.Sum512(password)
|
||
|
|
return bcrypt.CompareHashAndPassword(hashedPassword, sum[:])
|
||
|
|
}
|