local-server/cmd/dkl-local-server/sha512crypt.go

40 lines
974 B
Go

package main
import (
"encoding/base64"
crypthash "github.com/sergeymakinen/go-crypt/hash"
"github.com/sergeymakinen/go-crypt/sha512"
)
// for some reason, no implementation of crypt's sha512 is clean enough :(
func sha512crypt(password, seed []byte) (string, error) {
// loose salt entropy because of character restriction in the salt
salt := []byte(base64.RawStdEncoding.EncodeToString(seed))[:sha512.MaxSaltLength]
// - base64 allows '+' where the salt accepts '.'
for i, c := range salt {
if c == '+' {
salt[i] = '.'
}
}
scheme := struct {
HashPrefix string
Rounds uint32 `hash:"param:rounds,omitempty"`
Salt []byte
Sum [86]byte
}{
HashPrefix: sha512.Prefix,
Rounds: sha512.DefaultRounds,
Salt: salt,
}
key, err := sha512.Key([]byte(password), scheme.Salt, scheme.Rounds)
if err != nil {
return "", err
}
crypthash.LittleEndianEncoding.Encode(scheme.Sum[:], key)
return crypthash.Marshal(scheme)
}