/**
* Return the fingerprint of this key's parent as an int value, or zero if this key is the root
* node of the key hierarchy. Raise an exception if the arguments are inconsistent. This method
* exists to avoid code repetition in the constructors.
*/
private int ascertainParentFingerprint(DeterministicKey parentKey, int parentFingerprint)
throws IllegalArgumentException {
if (parentFingerprint != 0) {
if (parent != null)
checkArgument(
parent.getFingerprint() == parentFingerprint,
"parent fingerprint mismatch",
Integer.toHexString(parent.getFingerprint()),
Integer.toHexString(parentFingerprint));
return parentFingerprint;
} else return 0;
}
/** Constructs a key from its components. This is not normally something you should use. */
public DeterministicKey(
ImmutableList<ChildNumber> childNumberPath,
byte[] chainCode,
BigInteger priv,
@Nullable DeterministicKey parent) {
super(priv, compressPoint(ECKey.publicPointFromPrivate(priv)));
checkArgument(chainCode.length == 32);
this.parent = parent;
this.childNumberPath = checkNotNull(childNumberPath);
this.chainCode = Arrays.copyOf(chainCode, chainCode.length);
this.depth = this.childNumberPath.size();
this.parentFingerprint = (parent != null) ? parent.getFingerprint() : 0;
}
/**
* Deserialize an HD Key.
*
* @param parent The parent node in the given key's deterministic hierarchy.
*/
public static DeterministicKey deserialize(
NetworkParameters params, byte[] serializedKey, @Nullable DeterministicKey parent) {
ByteBuffer buffer = ByteBuffer.wrap(serializedKey);
int header = buffer.getInt();
if (header != params.getBip32HeaderPriv() && header != params.getBip32HeaderPub())
throw new IllegalArgumentException(
"Unknown header bytes: " + toBase58(serializedKey).substring(0, 4));
boolean pub = header == params.getBip32HeaderPub();
int depth =
buffer.get() & 0xFF; // convert signed byte to positive int since depth cannot be negative
final int parentFingerprint = buffer.getInt();
final int i = buffer.getInt();
final ChildNumber childNumber = new ChildNumber(i);
ImmutableList<ChildNumber> path;
if (parent != null) {
if (parentFingerprint == 0)
throw new IllegalArgumentException("Parent was provided but this key doesn't have one");
if (parent.getFingerprint() != parentFingerprint)
throw new IllegalArgumentException("Parent fingerprints don't match");
path = HDUtils.append(parent.getPath(), childNumber);
if (path.size() != depth) throw new IllegalArgumentException("Depth does not match");
} else {
if (depth >= 1)
// We have been given a key that is not a root key, yet we lack the object representing the
// parent.
// This can happen when deserializing an account key for a watching wallet. In this case,
// we assume that
// the client wants to conceal the key's position in the hierarchy. The path is truncated
// at the
// parent's node.
path = ImmutableList.of(childNumber);
else path = ImmutableList.of();
}
byte[] chainCode = new byte[32];
buffer.get(chainCode);
byte[] data = new byte[33];
buffer.get(data);
checkArgument(!buffer.hasRemaining(), "Found unexpected data in key");
if (pub) {
return new DeterministicKey(
path,
chainCode,
new LazyECPoint(ECKey.CURVE.getCurve(), data),
parent,
depth,
parentFingerprint);
} else {
return new DeterministicKey(
path, chainCode, new BigInteger(1, data), parent, depth, parentFingerprint);
}
}
