xs/vendor/gopkg.in/hlandau/passlib.v1/hash/pbkdf2/raw/parse.go

63 lines
1.2 KiB
Go

package raw
import (
"crypto/sha1"
"crypto/sha256"
"crypto/sha512"
"fmt"
"hash"
"strconv"
"strings"
)
// Indicates that a password hash or stub is invalid.
var ErrInvalidStub = fmt.Errorf("invalid stub")
// Indicates that the number of rounds specified is not in the valid range.
var ErrInvalidRounds = fmt.Errorf("invalid number of rounds")
var hashMap = map[string]func() hash.Hash{
"pbkdf2": sha1.New,
"pbkdf2-sha256": sha256.New,
"pbkdf2-sha512": sha512.New,
}
func Parse(stub string) (hashFunc func() hash.Hash, rounds int, salt []byte, hash string, err error) {
// does not start with $pbkdf2
if !strings.HasPrefix(stub, "$pbkdf2") {
err = ErrInvalidStub
return
}
parts := strings.Split(stub, "$")
if f, ok := hashMap[parts[1]]; ok {
hashFunc = f
} else {
err = ErrInvalidStub
return
}
roundsStr := parts[2]
var n uint64
n, err = strconv.ParseUint(roundsStr, 10, 31)
if err != nil {
err = ErrInvalidStub
return
}
rounds = int(n)
if rounds < MinRounds || rounds > MaxRounds {
err = ErrInvalidRounds
return
}
salt, err = Base64Decode(parts[3])
if err != nil {
err = fmt.Errorf("could not decode base64 salt")
return
}
hash = parts[4]
return
}