Sha256: 1d3d81009f4626ea74356fe12048f632f13a31c75f3ee4be2f15ae11677aab20
Contents?: true
Size: 1.06 KB
Versions: 16
Compression:
Stored size: 1.06 KB
Contents
package kdf
import (
"hash"
"math"
"github.com/dvsekhvalnov/jose2go/arrays"
)
const (
MaxInt = int(^uint(0)>>1);
)
// DeriveConcatKDF implements NIST SP 800-56A Concatenation Key Derivation Function. Derives
// key material of keydatalen bits size given Z (sharedSecret), OtherInfo (AlgorithmID |
// PartyUInfo | PartyVInfo | SuppPubInfo | SuppPrivInfo) and hash function
func DeriveConcatKDF(keydatalen int, sharedSecret, algId, partyUInfo, partyVInfo, suppPubInfo, suppPrivInfo []byte, h hash.Hash) []byte {
otherInfo := arrays.Concat(algId, partyUInfo, partyVInfo, suppPubInfo, suppPrivInfo)
keyLenBytes := keydatalen >> 3
reps := int(math.Ceil(float64(keyLenBytes) / float64(h.Size())))
if reps > MaxInt {
panic("kdf.DeriveConcatKDF: too much iterations (more than 2^32-1).")
}
dk:=make([]byte, 0, keyLenBytes)
for counter := 1;counter <= reps;counter++ {
h.Reset()
counterBytes:=arrays.UInt32ToBytes(uint32(counter))
h.Write(counterBytes)
h.Write(sharedSecret)
h.Write(otherInfo)
dk = h.Sum(dk)
}
return dk[:keyLenBytes]
}
Version data entries
16 entries across 16 versions & 1 rubygems