/**
* Copyright 2011 Google Inc.
*
* 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 com.google.devcoin.core;
import com.google.devcoin.params.MainNetParams;
import com.google.devcoin.params.TestNet2Params;
import com.google.devcoin.params.TestNet3Params;
import com.google.devcoin.params.UnitTestParams;
import com.google.devcoin.script.Script;
import com.google.devcoin.script.ScriptOpCodes;
import com.google.common.base.Objects;
import org.spongycastle.util.encoders.Hex;
import java.io.ByteArrayOutputStream;
import java.io.Serializable;
import java.math.BigInteger;
import java.util.HashMap;
import java.util.Map;
import static com.google.devcoin.core.Utils.COIN;
/**
* <p>NetworkParameters contains the data needed for working with an instantiation of a Bitcoin chain.</p>
*
* <p>This is an abstract class, concrete instantiations can be found in the params package. There are four:
* one for the main network ({@link MainNetParams}), one for the public test network, and two others that are
* intended for unit testing and local app development purposes. Although this class contains some aliases for
* them, you are encouraged to call the static get() methods on each specific params class directly.</p>
*/
public abstract class NetworkParameters implements Serializable {
/**
* The protocol version this library implements.
*/
public static final int PROTOCOL_VERSION = 70001;
/**
* The alert signing key originally owned by Satoshi, and now passed on to Gavin along with a few others.
*/
public static final byte[] SATOSHI_KEY = Hex.decode("04fc9702847840aaf195de8442ebecedf5b095cdbb9bc716bda9110971b28a49e0ead8564ff0db22209e0374782c093bb899692d524e9d6a6956e7c5ecbcd68284");
/** The string returned by getId() for the main, production network where people trade things. */
public static final String ID_MAINNET = "org.devcoin.production";
/** The string returned by getId() for the testnet. */
public static final String ID_TESTNET = "org.devcoin.test";
/** Unit test network. */
public static final String ID_UNITTESTNET = "com.google.devcoin.unittest";
// TODO: Seed nodes should be here as well.
protected Block genesisBlock;
protected BigInteger proofOfWorkLimit;
protected int port;
protected long packetMagic;
protected int addressHeader;
protected int dumpedPrivateKeyHeader;
protected int interval;
protected int targetTimespan;
protected byte[] alertSigningKey;
/**
* See getId(). This may be null for old deserialized wallets. In that case we derive it heuristically
* by looking at the port number.
*/
protected String id;
/**
* The depth of blocks required for a coinbase transaction to be spendable.
*/
protected int spendableCoinbaseDepth;
protected int subsidyDecreaseBlockCount;
protected int[] acceptableAddressCodes;
protected String[] dnsSeeds;
protected Map<Integer, Sha256Hash> checkpoints = new HashMap<Integer, Sha256Hash>();
protected NetworkParameters() {
alertSigningKey = SATOSHI_KEY;
genesisBlock = createGenesis(this);
}
private static Block createGenesis(NetworkParameters n) {
Block genesisBlock = new Block(n);
Transaction t = new Transaction(n);
try {
// A script containing the difficulty bits and the following message:
//
// "The Times web front page 22-Jul-2011 Europe hails 'historic' deal to save single currency";
byte[] bytes = Hex.decode
("04ffff001d01044c595468652054696d6573207765622066726f6e7420706167652032322d4a756c2d32303131204575726f7065206861696c732027686973746f72696327206465616c20746f20736176652073696e676c652063757272656e6379");
t.addInput(new TransactionInput(n, t, bytes));
ByteArrayOutputStream scriptPubKeyBytes = new ByteArrayOutputStream();
Script.writeBytes(scriptPubKeyBytes, Hex.decode
("04678afdb0fe5548271967f1a67130b7105cd6a828e03909a67962e0ea1f61deb649f6bc3f4cef38c4f35504e51ec112de5c384df7ba0b8d578a4c702b6bf11d5f"));
scriptPubKeyBytes.write(ScriptOpCodes.OP_CHECKSIG);
t.addOutput(new TransactionOutput(n, t, Utils.toNanoCoins(50, 0), scriptPubKeyBytes.toByteArray()));
} catch (Exception e) {
// Cannot happen.
throw new RuntimeException(e);
}
genesisBlock.addTransaction(t);
return genesisBlock;
}
public static final int TARGET_TIMESPAN = 14 * 24 * 60 * 60; // 2 weeks per difficulty cycle, on average.
public static final int TARGET_SPACING = 10 * 60; // 10 minutes per block.
public static final int INTERVAL = TARGET_TIMESPAN / TARGET_SPACING;
/**
* Blocks with a timestamp after this should enforce BIP 16, aka "Pay to script hash". This BIP changed the
* network rules in a soft-forking manner, that is, blocks that don't follow the rules are accepted but not
* mined upon and thus will be quickly re-orged out as long as the majority are enforcing the rule.
*/
public static final int BIP16_ENFORCE_TIME = 1377993600;
/**
* The maximum money to be generated
*/
public static final BigInteger MAX_MONEY = new BigInteger("21000000000", 10).multiply(COIN);
/** Alias for TestNet3Params.get(), use that instead. */
@Deprecated
public static NetworkParameters testNet() {
return TestNet3Params.get();
}
/** Alias for TestNet2Params.get(), use that instead. */
@Deprecated
public static NetworkParameters testNet2() {
return TestNet2Params.get();
}
/** Alias for TestNet3Params.get(), use that instead. */
@Deprecated
public static NetworkParameters testNet3() {
return TestNet3Params.get();
}
/** Alias for MainNetParams.get(), use that instead */
@Deprecated
public static NetworkParameters prodNet() {
return MainNetParams.get();
}
/** Returns a testnet params modified to allow any difficulty target. */
@Deprecated
public static NetworkParameters unitTests() {
return UnitTestParams.get();
}
/**
* A Java package style string acting as unique ID for these parameters
*/
public String getId() {
return id;
}
@Override
public boolean equals(Object other) {
if (!(other instanceof NetworkParameters)) return false;
NetworkParameters o = (NetworkParameters) other;
return o.getId().equals(getId());
}
@Override
public int hashCode() {
return Objects.hashCode(getId());
}
/** Returns the network parameters for the given string ID or NULL if not recognized. */
public static NetworkParameters fromID(String id) {
if (id.equals(ID_MAINNET)) {
return MainNetParams.get();
} else if (id.equals(ID_TESTNET)) {
return TestNet3Params.get();
} else if (id.equals(ID_UNITTESTNET)) {
return UnitTestParams.get();
} else {
return null;
}
}
public int getSpendableCoinbaseDepth() {
return spendableCoinbaseDepth;
}
/**
* Returns true if the block height is either not a checkpoint, or is a checkpoint and the hash matches.
*/
public boolean passesCheckpoint(int height, Sha256Hash hash) {
Sha256Hash checkpointHash = checkpoints.get(height);
return checkpointHash == null || checkpointHash.equals(hash);
}
/**
* Returns true if the given height has a recorded checkpoint.
*/
public boolean isCheckpoint(int height) {
Sha256Hash checkpointHash = checkpoints.get(height);
return checkpointHash != null;
}
public int getSubsidyDecreaseBlockCount() {
return subsidyDecreaseBlockCount;
}
/** Returns DNS names that when resolved, give IP addresses of active peers. */
public String[] getDnsSeeds() {
return dnsSeeds;
}
/**
* <p>Genesis block for this chain.</p>
*
* <p>The first block in every chain is a well known constant shared between all Bitcoin implemenetations. For a
* block to be valid, it must be eventually possible to work backwards to the genesis block by following the
* prevBlockHash pointers in the block headers.</p>
*
* <p>The genesis blocks for both test and prod networks contain the timestamp of when they were created,
* and a message in the coinbase transaction. It says, <i>"The Times 03/Jan/2009 Chancellor on brink of second
* bailout for banks"</i>.</p>
*/
public Block getGenesisBlock() {
return genesisBlock;
}
/** Default TCP port on which to connect to nodes. */
public int getPort() {
return port;
}
/** The header bytes that identify the start of a packet on this network. */
public long getPacketMagic() {
return packetMagic;
}
/**
* First byte of a base58 encoded address. See {@link com.google.devcoin.core.Address}. This is the same as acceptableAddressCodes[0] and
* is the one used for "normal" addresses. Other types of address may be encountered with version codes found in
* the acceptableAddressCodes array.
*/
public int getAddressHeader() {
return addressHeader;
}
/** First byte of a base58 encoded dumped private key. See {@link com.google.devcoin.core.DumpedPrivateKey}. */
public int getDumpedPrivateKeyHeader() {
return dumpedPrivateKeyHeader;
}
/**
* How much time in seconds is supposed to pass between "interval" blocks. If the actual elapsed time is
* significantly different from this value, the network difficulty formula will produce a different value. Both
* test and production Bitcoin networks use 2 weeks (1209600 seconds).
*/
public int getTargetTimespan() {
return targetTimespan;
}
/**
* The version codes that prefix addresses which are acceptable on this network. Although Satoshi intended these to
* be used for "versioning", in fact they are today used to discriminate what kind of data is contained in the
* address and to prevent accidentally sending coins across chains which would destroy them.
*/
public int[] getAcceptableAddressCodes() {
return acceptableAddressCodes;
}
/**
* If we are running in testnet-in-a-box mode, we allow connections to nodes with 0 non-genesis blocks.
*/
public boolean allowEmptyPeerChain() {
return true;
}
/** How many blocks pass between difficulty adjustment periods. Bitcoin standardises this to be 2015. */
public int getInterval() {
return interval;
}
/** What the easiest allowable proof of work should be. */
public BigInteger getProofOfWorkLimit() {
return proofOfWorkLimit;
}
/**
* The key used to sign {@link com.google.devcoin.core.AlertMessage}s. You can use {@link com.google.devcoin.core.ECKey#verify(byte[], byte[], byte[])} to verify
* signatures using it.
*/
public byte[] getAlertSigningKey() {
return alertSigningKey;
}
}