/*
* Copyright 2011 Google Inc.
* Copyright 2014 Giannis Dzegoutanis
* Copyright 2015 Andreas Schildbach
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.bitcoinj.core;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import org.bitcoinj.params.Networks;
import org.bitcoinj.script.Script;
import javax.annotation.Nullable;
import static com.google.common.base.Preconditions.checkArgument;
import static com.google.common.base.Preconditions.checkNotNull;
/**
* <p>A Bitcoin address looks like 1MsScoe2fTJoq4ZPdQgqyhgWeoNamYPevy and is derived from an elliptic curve public key
* plus a set of network parameters. Not to be confused with a {@link PeerAddress} or {@link AddressMessage}
* which are about network (TCP) addresses.</p>
*
* <p>A standard address is built by taking the RIPE-MD160 hash of the public key bytes, with a version prefix and a
* checksum suffix, then encoding it textually as base58. The version prefix is used to both denote the network for
* which the address is valid (see {@link NetworkParameters}, and also to indicate how the bytes inside the address
* should be interpreted. Whilst almost all addresses today are hashes of public keys, another (currently unsupported
* type) can contain a hash of a script instead.</p>
*/
public class Address extends VersionedChecksummedBytes {
/**
* An address is a RIPEMD160 hash of a public key, therefore is always 160 bits or 20 bytes.
*/
public static final int LENGTH = 20;
private transient NetworkParameters params;
/**
* Construct an address from parameters, the address version, and the hash160 form. Example:<p>
*
* <pre>new Address(MainNetParams.get(), NetworkParameters.getAddressHeader(), Hex.decode("4a22c3c4cbb31e4d03b15550636762bda0baf85a"));</pre>
*/
public Address(NetworkParameters params, int version, byte[] hash160) throws WrongNetworkException {
super(version, hash160);
checkNotNull(params);
checkArgument(hash160.length == 20, "Addresses are 160-bit hashes, so you must provide 20 bytes");
if (!isAcceptableVersion(params, version))
throw new WrongNetworkException(version, params.getAcceptableAddressCodes());
this.params = params;
}
/** Returns an Address that represents the given P2SH script hash. */
public static Address fromP2SHHash(NetworkParameters params, byte[] hash160) {
try {
return new Address(params, params.getP2SHHeader(), hash160);
} catch (WrongNetworkException e) {
throw new RuntimeException(e); // Cannot happen.
}
}
/** Returns an Address that represents the script hash extracted from the given scriptPubKey */
public static Address fromP2SHScript(NetworkParameters params, Script scriptPubKey) {
checkArgument(scriptPubKey.isPayToScriptHash(), "Not a P2SH script");
return fromP2SHHash(params, scriptPubKey.getPubKeyHash());
}
/**
* Construct an address from its Base58 representation.
* @param params
* The expected NetworkParameters or null if you don't want validation.
* @param base58
* The textual form of the address, such as "17kzeh4N8g49GFvdDzSf8PjaPfyoD1MndL".
* @throws AddressFormatException
* if the given base58 doesn't parse or the checksum is invalid
* @throws WrongNetworkException
* if the given address is valid but for a different chain (eg testnet vs mainnet)
*/
public static Address fromBase58(@Nullable NetworkParameters params, String base58) throws AddressFormatException {
return new Address(params, base58);
}
/**
* Construct an address from parameters and the hash160 form. Example:<p>
*
* <pre>new Address(MainNetParams.get(), Hex.decode("4a22c3c4cbb31e4d03b15550636762bda0baf85a"));</pre>
*/
public Address(NetworkParameters params, byte[] hash160) {
super(params.getAddressHeader(), hash160);
checkArgument(hash160.length == 20, "Addresses are 160-bit hashes, so you must provide 20 bytes");
this.params = params;
}
/** @deprecated Use {@link #fromBase58(NetworkParameters, String)} */
@Deprecated
public Address(@Nullable NetworkParameters params, String address) throws AddressFormatException {
super(address);
if (params != null) {
if (!isAcceptableVersion(params, version)) {
throw new WrongNetworkException(version, params.getAcceptableAddressCodes());
}
this.params = params;
} else {
NetworkParameters paramsFound = null;
for (NetworkParameters p : Networks.get()) {
if (isAcceptableVersion(p, version)) {
paramsFound = p;
break;
}
}
if (paramsFound == null)
throw new AddressFormatException("No network found for " + address);
this.params = paramsFound;
}
}
/** The (big endian) 20 byte hash that is the core of a Bitcoin address. */
public byte[] getHash160() {
return bytes;
}
/**
* Returns true if this address is a Pay-To-Script-Hash (P2SH) address.
* See also https://github.com/bitcoin/bips/blob/master/bip-0013.mediawiki: Address Format for pay-to-script-hash
*/
public boolean isP2SHAddress() {
final NetworkParameters parameters = getParameters();
return parameters != null && this.version == parameters.p2shHeader;
}
/**
* Examines the version byte of the address and attempts to find a matching NetworkParameters. If you aren't sure
* which network the address is intended for (eg, it was provided by a user), you can use this to decide if it is
* compatible with the current wallet. You should be able to handle a null response from this method. Note that the
* parameters returned is not necessarily the same as the one the Address was created with.
*
* @return a NetworkParameters representing the network the address is intended for.
*/
public NetworkParameters getParameters() {
return params;
}
/**
* Given an address, examines the version byte and attempts to find a matching NetworkParameters. If you aren't sure
* which network the address is intended for (eg, it was provided by a user), you can use this to decide if it is
* compatible with the current wallet.
* @return a NetworkParameters of the address
* @throws AddressFormatException if the string wasn't of a known version
*/
public static NetworkParameters getParametersFromAddress(String address) throws AddressFormatException {
try {
return Address.fromBase58(null, address).getParameters();
} catch (WrongNetworkException e) {
throw new RuntimeException(e); // Cannot happen.
}
}
/**
* Check if a given address version is valid given the NetworkParameters.
*/
private static boolean isAcceptableVersion(NetworkParameters params, int version) {
for (int v : params.getAcceptableAddressCodes()) {
if (version == v) {
return true;
}
}
return false;
}
/**
* This implementation narrows the return type to <code>Address</code>.
*/
@Override
public Address clone() throws CloneNotSupportedException {
return (Address) super.clone();
}
// Java serialization
private void writeObject(ObjectOutputStream out) throws IOException {
out.defaultWriteObject();
out.writeUTF(params.id);
}
private void readObject(ObjectInputStream in) throws IOException, ClassNotFoundException {
in.defaultReadObject();
params = NetworkParameters.fromID(in.readUTF());
}
}