// ReadKeyRing reads a key ring of public keys from a file in JSON object format,
// and also inserts the pubkey of a keypair if it's not already present (handles
// bug in URS implementation).
func ReadKeyRing(filename string, kp *ecdsa.PrivateKey) (*PublicKeyRing, error) {
// Load the file
f, err := ioutil.ReadFile(filename)
if err != nil {
fError := errors.New("os.Open: Couldn't open keyring file.")
return nil, fError
}
// Unmarshall the loaded file into a map
var keyMap = make(map[string]string)
err = json.Unmarshal(f, &keyMap)
if err != nil {
str := fmt.Sprintf("json error: Couldn't unmarshall keyring file.", err)
jsonError := errors.New(str)
return nil, jsonError
}
kr := NewPublicKeyRing(uint(len(keyMap)))
// Stick the pubkeys into the keyring as long as it doesn't belong to the
// keypair given.
for i := 0; i < len(keyMap); i++ {
pkBytes, errDecode := hex.DecodeString(keyMap[strconv.Itoa(i)])
if errDecode != nil {
decodeError := errors.New("decode error: Couldn't decode hex.")
return nil, decodeError
}
pubkey, errParse := btcec.ParsePubKey(pkBytes, btcec.S256())
if errParse != nil {
return nil, errParse
}
ecdsaPubkey := ecdsa.PublicKey{pubkey.Curve, pubkey.X, pubkey.Y}
if kp == nil || !CmpPubKey(&kp.PublicKey, &ecdsaPubkey) {
kr.Add(ecdsaPubkey)
} else {
kr.Add(kp.PublicKey)
}
}
// Stick the keypair in if it's missing.
if kp != nil && !kr.keyInKeyRing(&kp.PublicKey) {
kr.Add(kp.PublicKey)
}
return kr, nil
}
// ReadKeyPair reads an ECDSA keypair a file in JSON object format.
// Example JSON input:
// {
// "privkey": "..."
// }
// It also checks if a pubkey is in the keyring and, if not, appends it to the
// keyring.
func ReadKeyPair(filename string) (*ecdsa.PrivateKey, error) {
// Load the file
f, err := ioutil.ReadFile(filename)
if err != nil {
fError := errors.New("os.Open: Couldn't open keypair file.")
return nil, fError
}
// Unmarshall the loaded file into a map.
var keyMap = make(map[string]string)
var pubkey *ecdsa.PublicKey
var privkey *ecdsa.PrivateKey
err = json.Unmarshal(f, &keyMap)
if err != nil {
jsonError := errors.New("json error: Couldn't unmarshall keypair file.")
return nil, jsonError
}
privBytes, errDecode := hex.DecodeString(keyMap["privkey"])
if errDecode != nil {
decodeError := errors.New("decode error: Couldn't decode hex for privkey.")
return nil, decodeError
}
// PrivKeyFromBytes doesn't return an error, so this could possibly be ugly.
privkeyBtcec, _ := btcec.PrivKeyFromBytes(btcec.S256(), privBytes)
pubBytes, errDecode := hex.DecodeString(keyMap["pubkey"])
if errDecode != nil {
decodeError := errors.New("decode error: Couldn't decode hex for privkey.")
return nil, decodeError
}
pubkeyBtcec, errParse := btcec.ParsePubKey(pubBytes, btcec.S256())
if errParse != nil {
return nil, errParse
}
// Assign the things to return
pubkey = &ecdsa.PublicKey{pubkeyBtcec.Curve,
pubkeyBtcec.X,
pubkeyBtcec.Y}
privkey = &ecdsa.PrivateKey{*pubkey, privkeyBtcec.D}
return privkey, nil
}