From 77a47c251ecac64ed625c7963aa9bb2c4f09fcbd Mon Sep 17 00:00:00 2001 From: Dimitri Sokolyuk Date: Tue, 18 Jul 2017 01:14:06 +0200 Subject: Split --- key/enc.go | 59 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 59 insertions(+) create mode 100644 key/enc.go (limited to 'key/enc.go') diff --git a/key/enc.go b/key/enc.go new file mode 100644 index 0000000..2f2d48d --- /dev/null +++ b/key/enc.go @@ -0,0 +1,59 @@ +package key + +import ( + "bytes" + "crypto/sha512" + + "golang.org/x/crypto/ed25519" +) + +type Enc struct { + PKAlg [2]byte + KDFAlg [2]byte + KDFRounds uint32 + Salt [16]byte + Checksum [8]byte + KeyNum [8]byte + Key [ed25519.PrivateKeySize]byte +} + +func (v *Enc) Sign(message []byte) *Sig { + sig := &Sig{PKAlg: v.PKAlg, KeyNum: v.KeyNum} + copy(sig.Sig[:], ed25519.Sign(ed25519.PrivateKey(v.Key[:]), message)) + return sig +} + +func (v *Enc) Check() error { + if v.PKAlg != pkAlg { + return ErrInvalidPK + } + if v.KDFAlg != kdfAlg { + return ErrInvalidKDF + } + sum := sha512.Sum512(v.Key[:]) + if !bytes.Equal(sum[:len(v.Checksum)], v.Checksum[:]) { + return ErrInvalidKey + } + return nil +} + +func (v *Enc) MarshalBinary() ([]byte, error) { + return Marshal(v) +} + +func ParseEnc(data []byte, d KeyDeriver) (*Enc, error) { + var enc *Enc + if err := Unmarshal(data, enc); err != nil { + return nil, err + } + if d != nil && enc.KDFRounds > 0 { + xor, err := d.DeriveKey(enc.Salt[:], int(enc.KDFRounds), len(enc.Key)) + if err != nil { + return nil, err + } + for i := range xor { + enc.Key[i] ^= xor[i] + } + } + return enc, enc.Check() +} -- cgit v1.2.3