/*
* Copyright 2013 Matt Corallo
* 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 com.google.common.base.Objects;
import java.io.IOException;
import java.io.OutputStream;
import java.util.Locale;
/**
* <p>A message sent by nodes when a message we sent was rejected (ie a transaction had too little fee/was invalid/etc).</p>
*
* <p>Instances of this class are not safe for use by multiple threads.</p>
*/
public class RejectMessage extends Message {
private String message, reason;
public enum RejectCode {
/** The message was not able to be parsed */
MALFORMED((byte) 0x01),
/** The message described an invalid object */
INVALID((byte) 0x10),
/** The message was obsolete or described an object which is obsolete (eg unsupported, old version, v1 block) */
OBSOLETE((byte) 0x11),
/**
* The message was relayed multiple times or described an object which is in conflict with another.
* This message can describe errors in protocol implementation or the presence of an attempt to DOUBLE SPEND.
*/
DUPLICATE((byte) 0x12),
/**
* The message described an object was not standard and was thus not accepted.
* Bitcoin Core has a concept of standard transaction forms, which describe scripts and encodings which
* it is willing to relay further. Other transactions are neither relayed nor mined, though they are considered
* valid if they appear in a block.
*/
NONSTANDARD((byte) 0x40),
/**
* This refers to a specific form of NONSTANDARD transactions, which have an output smaller than some constant
* defining them as dust (this is no longer used).
*/
DUST((byte) 0x41),
/** The messages described an object which did not have sufficient fee to be relayed further. */
INSUFFICIENTFEE((byte) 0x42),
/** The message described a block which was invalid according to hard-coded checkpoint blocks. */
CHECKPOINT((byte) 0x43),
OTHER((byte) 0xff);
byte code;
RejectCode(byte code) { this.code = code; }
static RejectCode fromCode(byte code) {
for (RejectCode rejectCode : RejectCode.values())
if (rejectCode.code == code)
return rejectCode;
return OTHER;
}
}
private RejectCode code;
private Sha256Hash messageHash;
public RejectMessage(NetworkParameters params, byte[] payload) throws ProtocolException {
super(params, payload, 0);
}
/** Constructs a reject message that fingers the object with the given hash as rejected for the given reason. */
public RejectMessage(NetworkParameters params, RejectCode code, Sha256Hash hash, String message, String reason) throws ProtocolException {
super(params);
this.code = code;
this.messageHash = hash;
this.message = message;
this.reason = reason;
}
@Override
protected void parse() throws ProtocolException {
message = readStr();
code = RejectCode.fromCode(readBytes(1)[0]);
reason = readStr();
if (message.equals("block") || message.equals("tx"))
messageHash = readHash();
length = cursor - offset;
}
@Override
public void bitcoinSerializeToStream(OutputStream stream) throws IOException {
byte[] messageBytes = message.getBytes("UTF-8");
stream.write(new VarInt(messageBytes.length).encode());
stream.write(messageBytes);
stream.write(code.code);
byte[] reasonBytes = reason.getBytes("UTF-8");
stream.write(new VarInt(reasonBytes.length).encode());
stream.write(reasonBytes);
if ("block".equals(message) || "tx".equals(message))
stream.write(messageHash.getReversedBytes());
}
/**
* Provides the type of message which was rejected by the peer.
* Note that this is ENTIRELY UNTRUSTED and should be sanity-checked before it is printed or processed.
*/
public String getRejectedMessage() {
return message;
}
/**
* Provides the hash of the rejected object (if getRejectedMessage() is either "tx" or "block"), otherwise null.
*/
public Sha256Hash getRejectedObjectHash() {
return messageHash;
}
/**
* The reason code given for why the peer rejected the message.
*/
public RejectCode getReasonCode() {
return code;
}
/**
* The reason message given for rejection.
* Note that this is ENTIRELY UNTRUSTED and should be sanity-checked before it is printed or processed.
*/
public String getReasonString() {
return reason;
}
/**
* A String representation of the relevant details of this reject message.
* Be aware that the value returned by this method includes the value returned by
* {@link #getReasonString() getReasonString}, which is taken from the reject message unchecked.
* Through malice or otherwise, it might contain control characters or other harmful content.
*/
@Override
public String toString() {
Sha256Hash hash = getRejectedObjectHash();
return String.format(Locale.US, "Reject: %s %s for reason '%s' (%d)", getRejectedMessage(),
hash != null ? hash : "", getReasonString(), getReasonCode().code);
}
@Override
public boolean equals(Object o) {
if (this == o) return true;
if (o == null || getClass() != o.getClass()) return false;
RejectMessage other = (RejectMessage) o;
return message.equals(other.message) && code.equals(other.code)
&& reason.equals(other.reason) && messageHash.equals(other.messageHash);
}
@Override
public int hashCode() {
return Objects.hashCode(message, code, reason, messageHash);
}
}