public static DeterministicKey createMasterPubKeyFromBytes(byte[] pubKeyBytes, byte[] chainCode) {
return new DeterministicKey(
ImmutableList.<ChildNumber>of(),
chainCode,
ECKey.CURVE.getCurve().decodePoint(pubKeyBytes),
null,
null);
}
private static RawKeyBytes deriveChildKeyBytesFromPublic(
DeterministicKey parent, ChildNumber childNumber) throws HDDerivationException {
checkArgument(!childNumber.isHardened(), "Can't use private derivation with public keys only.");
byte[] parentPublicKey = ECKey.compressPoint(parent.getPubKeyPoint()).getEncoded();
assert parentPublicKey.length == 33 : parentPublicKey.length;
ByteBuffer data = ByteBuffer.allocate(37);
data.put(parentPublicKey);
data.putInt(childNumber.i());
byte[] i = HDUtils.hmacSha512(parent.getChainCode(), data.array());
assert i.length == 64 : i.length;
byte[] il = Arrays.copyOfRange(i, 0, 32);
byte[] chainCode = Arrays.copyOfRange(i, 32, 64);
BigInteger ilInt = new BigInteger(1, il);
assertLessThanN(ilInt, "Illegal derived key: I_L >= n");
ECPoint Ki = ECKey.CURVE.getG().multiply(ilInt).add(parent.getPubKeyPoint());
assertNonInfinity(Ki, "Illegal derived key: derived public key equals infinity.");
return new RawKeyBytes(Ki.getEncoded(true), chainCode);
}
/**
* @throws HDDerivationException if private derivation is attempted for a public-only parent key,
* or if the resulting derived key is invalid (eg. private key == 0).
*/
public static DeterministicKey deriveChildKey(DeterministicKey parent, ChildNumber childNumber)
throws HDDerivationException {
if (parent.isPubKeyOnly()) {
RawKeyBytes rawKey = deriveChildKeyBytesFromPublic(parent, childNumber);
return new DeterministicKey(
HDUtils.append(parent.getPath(), childNumber),
rawKey.chainCode,
ECKey.CURVE.getCurve().decodePoint(rawKey.keyBytes), // c'tor will compress
null,
parent);
} else {
RawKeyBytes rawKey = deriveChildKeyBytesFromPrivate(parent, childNumber);
return new DeterministicKey(
HDUtils.append(parent.getPath(), childNumber),
rawKey.chainCode,
new BigInteger(1, rawKey.keyBytes),
parent);
}
}
private static RawKeyBytes deriveChildKeyBytesFromPrivate(
DeterministicKey parent, ChildNumber childNumber) throws HDDerivationException {
checkArgument(parent.hasPrivKey(), "Parent key must have private key bytes for this method.");
byte[] parentPublicKey = ECKey.compressPoint(parent.getPubKeyPoint()).getEncoded();
assert parentPublicKey.length == 33 : parentPublicKey.length;
ByteBuffer data = ByteBuffer.allocate(37);
if (childNumber.isHardened()) {
data.put(parent.getPrivKeyBytes33());
} else {
data.put(parentPublicKey);
}
data.putInt(childNumber.i());
byte[] i = HDUtils.hmacSha512(parent.getChainCode(), data.array());
assert i.length == 64 : i.length;
byte[] il = Arrays.copyOfRange(i, 0, 32);
byte[] chainCode = Arrays.copyOfRange(i, 32, 64);
BigInteger ilInt = new BigInteger(1, il);
assertLessThanN(ilInt, "Illegal derived key: I_L >= n");
final BigInteger priv = parent.getPrivKey();
BigInteger ki = priv.add(ilInt).mod(ECKey.CURVE.getN());
assertNonZero(ki, "Illegal derived key: derived private key equals 0.");
return new RawKeyBytes(ki.toByteArray(), chainCode);
}
private static void assertLessThanN(BigInteger integer, String errorMessage) {
if (integer.compareTo(ECKey.CURVE.getN()) > 0) throw new HDDerivationException(errorMessage);
}
private static void assertNonInfinity(ECPoint point, String errorMessage) {
if (point.equals(ECKey.CURVE.getCurve().getInfinity()))
throw new HDDerivationException(errorMessage);
}
/**
* Returns all the key chains found in the given list of keys. Typically there will only be one,
* but in the case of key rotation it can happen that there are multiple chains found.
*/
public static List<DeterministicKeyChain> fromProtobuf(
List<Protos.Key> keys, @Nullable KeyCrypter crypter) throws UnreadableWalletException {
List<DeterministicKeyChain> chains = newLinkedList();
DeterministicSeed seed = null;
DeterministicKeyChain chain = null;
int lookaheadSize = -1;
for (Protos.Key key : keys) {
final Protos.Key.Type t = key.getType();
if (t == Protos.Key.Type.DETERMINISTIC_MNEMONIC) {
if (chain != null) {
checkState(lookaheadSize >= 0);
chain.setLookaheadSize(lookaheadSize);
chain.maybeLookAhead();
chains.add(chain);
chain = null;
}
long timestamp = key.getCreationTimestamp() / 1000;
String passphrase = DEFAULT_PASSPHRASE_FOR_MNEMONIC; // FIXME allow non-empty passphrase
if (key.hasSecretBytes()) {
seed = new DeterministicSeed(key.getSecretBytes().toStringUtf8(), passphrase, timestamp);
} else if (key.hasEncryptedData()) {
EncryptedData data =
new EncryptedData(
key.getEncryptedData().getInitialisationVector().toByteArray(),
key.getEncryptedData().getEncryptedPrivateKey().toByteArray());
seed = new DeterministicSeed(data, timestamp);
} else {
throw new UnreadableWalletException("Malformed key proto: " + key.toString());
}
if (log.isDebugEnabled()) log.debug("Deserializing: DETERMINISTIC_MNEMONIC: {}", seed);
} else if (t == Protos.Key.Type.DETERMINISTIC_KEY) {
if (!key.hasDeterministicKey())
throw new UnreadableWalletException(
"Deterministic key missing extra data: " + key.toString());
byte[] chainCode = key.getDeterministicKey().getChainCode().toByteArray();
// Deserialize the path through the tree.
LinkedList<ChildNumber> path = newLinkedList();
for (int i : key.getDeterministicKey().getPathList()) path.add(new ChildNumber(i));
// Deserialize the public key and path.
ECPoint pubkey = ECKey.CURVE.getCurve().decodePoint(key.getPublicKey().toByteArray());
final ImmutableList<ChildNumber> immutablePath = ImmutableList.copyOf(path);
// Possibly create the chain, if we didn't already do so yet.
boolean isWatchingAccountKey = false;
boolean isFollowingKey = false;
// save previous chain if any if the key is marked as following. Current key and the next
// ones are to be
// placed in new following key chain
if (key.getDeterministicKey().getIsFollowing()) {
if (chain != null) {
checkState(lookaheadSize >= 0);
chain.setLookaheadSize(lookaheadSize);
chain.maybeLookAhead();
chains.add(chain);
chain = null;
seed = null;
}
isFollowingKey = true;
}
if (chain == null) {
if (seed == null) {
DeterministicKey accountKey =
new DeterministicKey(immutablePath, chainCode, pubkey, null, null);
if (!accountKey.getPath().equals(ACCOUNT_ZERO_PATH))
throw new UnreadableWalletException(
"Expecting account key but found key with path: "
+ HDUtils.formatPath(accountKey.getPath()));
chain = new DeterministicKeyChain(accountKey, isFollowingKey);
isWatchingAccountKey = true;
} else {
chain = new DeterministicKeyChain(seed, crypter);
chain.lookaheadSize = LAZY_CALCULATE_LOOKAHEAD;
// If the seed is encrypted, then the chain is incomplete at this point. However, we
// will load
// it up below as we parse in the keys. We just need to check at the end that we've
// loaded
// everything afterwards.
}
}
// Find the parent key assuming this is not the root key, and not an account key for a
// watching chain.
DeterministicKey parent = null;
if (!path.isEmpty() && !isWatchingAccountKey) {
ChildNumber index = path.removeLast();
parent = chain.hierarchy.get(path, false, false);
path.add(index);
}
DeterministicKey detkey;
if (key.hasSecretBytes()) {
// Not encrypted: private key is available.
final BigInteger priv = new BigInteger(1, key.getSecretBytes().toByteArray());
detkey = new DeterministicKey(immutablePath, chainCode, pubkey, priv, parent);
} else {
if (key.hasEncryptedData()) {
Protos.EncryptedData proto = key.getEncryptedData();
EncryptedData data =
new EncryptedData(
proto.getInitialisationVector().toByteArray(),
proto.getEncryptedPrivateKey().toByteArray());
checkNotNull(crypter, "Encountered an encrypted key but no key crypter provided");
detkey = new DeterministicKey(immutablePath, chainCode, crypter, pubkey, data, parent);
} else {
// No secret key bytes and key is not encrypted: either a watching key or private key
// bytes
// will be rederived on the fly from the parent.
detkey = new DeterministicKey(immutablePath, chainCode, pubkey, null, parent);
}
}
if (key.hasCreationTimestamp())
detkey.setCreationTimeSeconds(key.getCreationTimestamp() / 1000);
if (log.isDebugEnabled()) log.debug("Deserializing: DETERMINISTIC_KEY: {}", detkey);
if (!isWatchingAccountKey) {
// If the non-encrypted case, the non-leaf keys (account, internal, external) have already
// been
// rederived and inserted at this point and the two lines below are just a no-op. In the
// encrypted
// case though, we can't rederive and we must reinsert, potentially building the heirarchy
// object
// if need be.
if (path.size() == 0) {
// Master key.
chain.rootKey = detkey;
chain.hierarchy = new DeterministicHierarchy(detkey);
} else if (path.size() == 2) {
if (detkey.getChildNumber().num() == 0) {
chain.externalKey = detkey;
chain.issuedExternalKeys = key.getDeterministicKey().getIssuedSubkeys();
lookaheadSize = Math.max(lookaheadSize, key.getDeterministicKey().getLookaheadSize());
} else if (detkey.getChildNumber().num() == 1) {
chain.internalKey = detkey;
chain.issuedInternalKeys = key.getDeterministicKey().getIssuedSubkeys();
}
}
}
chain.hierarchy.putKey(detkey);
chain.basicKeyChain.importKey(detkey);
}
}
if (chain != null) {
checkState(lookaheadSize >= 0);
chain.setLookaheadSize(lookaheadSize);
chain.maybeLookAhead();
chains.add(chain);
}
return chains;
}