Code:
using NBitcoin;
using NBitcoin.Protocol;
using NBitcoin.Protocol.Behaviors;
using System;
using System.Collections.Concurrent;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
namespace ConsoleApplication3
{
class Program
{
class Behavior : NodeBehavior
{
protected override void AttachCore()
{
AttachedNode.MessageReceived += AttachedNode_MessageReceived;
}
ConcurrentDictionary _Transactions = new ConcurrentDictionary();
void AttachedNode_MessageReceived(Node node, IncomingMessage message)
{
var inv = message.Message.Payload as InvPayload;
if(inv != null)
{
node.SendMessageAsync(new GetDataPayload(inv.ToArray()));
}
var tx = message.Message.Payload as TxPayload;
if(tx != null)
{
bool mutated = false;
foreach(var txin in tx.Object.Inputs)
{
List ops = new List();
foreach(var op in txin.ScriptSig.ToOps())
{
if(op.PushData != null && IsValidSignatureEncoding(op.PushData))
{
TransactionSignature sig = new TransactionSignature(op.PushData);
if(!sig.IsLowS)
mutated = true;
ops.Add(Op.GetPushOp(sig.MakeCanonical().ToBytes()));
}
else
{
ops.Add(op);
}
}
txin.ScriptSig = new Script(ops.ToArray());
}
if(mutated)
{
if(_Transactions.TryAdd(tx.Object.GetHash(), tx.Object))
{
SendMessageAsync(new InvPayload(tx.Object));
}
}
}
var data = message.Message.Payload as GetDataPayload;
if(data != null)
{
foreach(var inventory in data.Inventory)
{
var txx = _Transactions.TryGet(inventory.Hash);
node.SendMessageAsync(new TxPayload(txx));
Console.WriteLine("Broadcasted : " + inventory.Hash);
}
}
var reject = message.Message.Payload as RejectPayload;
if(reject != null)
{
Console.WriteLine("Reject " + reject.Hash + " for " + reject.Reason);
}
if(_Transactions.Count > 1000)
_Transactions.Clear();
}
private void SendMessageAsync(InvPayload invPayload)
{
var group = NodesGroup.GetNodeGroup(AttachedNode);
foreach(var node in group.ConnectedNodes.Where(n => n != AttachedNode))
{
node.SendMessageAsync(invPayload);
}
}
public override object Clone()
{
return new Behavior(_Transactions);
}
public Behavior()
{
}
protected override void DetachCore()
{
AttachedNode.MessageReceived -= AttachedNode_MessageReceived;
}
public Behavior(ConcurrentDictionary tx)
{
this._Transactions = tx;
}
}
static void Main(string[] args)
{
new Program().Run();
}
private void Run()
{
var parameters = new NodeConnectionParameters();
parameters.TemplateBehaviors.Add(new Behavior());
var group = new NodesGroup(Network.Main, parameters);
group.MaximumNodeConnection = 10;
group.Connect();
_Group = group;
_Group.ConnectedNodes.Added += ConnectedNodes_Added;
_Group.ConnectedNodes.Removed += ConnectedNodes_Added;
Console.ReadLine();
}
void ConnectedNodes_Added(object sender, NodeEventArgs e)
{
Console.WriteLine("Connected : " + _Group.ConnectedNodes.Count);
}
NodesGroup _Group;
public static bool IsValidSignatureEncoding(byte[] sig)
{
// Format: 0x30 [total-length] 0x02 [R-length] [R] 0x02 [S-length] [S] [sighash]
// * total-length: 1-byte length descriptor of everything that follows,
// excluding the sighash byte.
// * R-length: 1-byte length descriptor of the R value that follows.
// * R: arbitrary-length big-endian encoded R value. It must use the shortest
// possible encoding for a positive integers (which means no null bytes at
// the start, except a single one when the next byte has its highest bit set).
// * S-length: 1-byte length descriptor of the S value that follows.
// * S: arbitrary-length big-endian encoded S value. The same rules apply.
// * sighash: 1-byte value indicating what data is hashed (not part of the DER
// signature)
var signLen = sig.Length;
// Minimum and maximum size constraints.
if(signLen < 9 || signLen > 73)
return false;
// A signature is of type 0x30 (compound).
if(sig[0] != 0x30)
return false;
// Make sure the length covers the entire signature.
if(sig[1] != signLen - 3)
return false;
// Extract the length of the R element.
uint lenR = sig[3];
// Make sure the length of the S element is still inside the signature.
if(5 + lenR >= signLen)
return false;
// Extract the length of the S element.
uint lenS = sig[5 + lenR];
// Verify that the length of the signature matches the sum of the length
// of the elements.
if((lenR + lenS + 7) != signLen)
return false;
// Check whether the R element is an integer.
if(sig[2] != 0x02)
return false;
// Zero-length integers are not allowed for R.
if(lenR == 0)
return false;
// Negative numbers are not allowed for R.
if((sig[4] & 0x80) != 0)
return false;
// Null bytes at the start of R are not allowed, unless R would
// otherwise be interpreted as a negative number.
if(lenR > 1 && (sig[4] == 0x00) && (sig[5] & 0x80) == 0)
return false;
// Check whether the S element is an integer.
if(sig[lenR + 4] != 0x02)
return false;
// Zero-length integers are not allowed for S.
if(lenS == 0)
return false;
// Negative numbers are not allowed for S.
if((sig[lenR + 6] & 0x80) != 0)
return false;
// Null bytes at the start of S are not allowed, unless S would otherwise be
// interpreted as a negative number.
if(lenS > 1 && (sig[lenR + 6] == 0x00) && (sig[lenR + 7] & 0x80) == 0)
return false;
return true;
}
}
}
using NBitcoin.Protocol;
using NBitcoin.Protocol.Behaviors;
using System;
using System.Collections.Concurrent;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
namespace ConsoleApplication3
{
class Program
{
class Behavior : NodeBehavior
{
protected override void AttachCore()
{
AttachedNode.MessageReceived += AttachedNode_MessageReceived;
}
ConcurrentDictionary
void AttachedNode_MessageReceived(Node node, IncomingMessage message)
{
var inv = message.Message.Payload as InvPayload;
if(inv != null)
{
node.SendMessageAsync(new GetDataPayload(inv.ToArray()));
}
var tx = message.Message.Payload as TxPayload;
if(tx != null)
{
bool mutated = false;
foreach(var txin in tx.Object.Inputs)
{
List
foreach(var op in txin.ScriptSig.ToOps())
{
if(op.PushData != null && IsValidSignatureEncoding(op.PushData))
{
TransactionSignature sig = new TransactionSignature(op.PushData);
if(!sig.IsLowS)
mutated = true;
ops.Add(Op.GetPushOp(sig.MakeCanonical().ToBytes()));
}
else
{
ops.Add(op);
}
}
txin.ScriptSig = new Script(ops.ToArray());
}
if(mutated)
{
if(_Transactions.TryAdd(tx.Object.GetHash(), tx.Object))
{
SendMessageAsync(new InvPayload(tx.Object));
}
}
}
var data = message.Message.Payload as GetDataPayload;
if(data != null)
{
foreach(var inventory in data.Inventory)
{
var txx = _Transactions.TryGet(inventory.Hash);
node.SendMessageAsync(new TxPayload(txx));
Console.WriteLine("Broadcasted : " + inventory.Hash);
}
}
var reject = message.Message.Payload as RejectPayload;
if(reject != null)
{
Console.WriteLine("Reject " + reject.Hash + " for " + reject.Reason);
}
if(_Transactions.Count > 1000)
_Transactions.Clear();
}
private void SendMessageAsync(InvPayload invPayload)
{
var group = NodesGroup.GetNodeGroup(AttachedNode);
foreach(var node in group.ConnectedNodes.Where(n => n != AttachedNode))
{
node.SendMessageAsync(invPayload);
}
}
public override object Clone()
{
return new Behavior(_Transactions);
}
public Behavior()
{
}
protected override void DetachCore()
{
AttachedNode.MessageReceived -= AttachedNode_MessageReceived;
}
public Behavior(ConcurrentDictionary
{
this._Transactions = tx;
}
}
static void Main(string[] args)
{
new Program().Run();
}
private void Run()
{
var parameters = new NodeConnectionParameters();
parameters.TemplateBehaviors.Add(new Behavior());
var group = new NodesGroup(Network.Main, parameters);
group.MaximumNodeConnection = 10;
group.Connect();
_Group = group;
_Group.ConnectedNodes.Added += ConnectedNodes_Added;
_Group.ConnectedNodes.Removed += ConnectedNodes_Added;
Console.ReadLine();
}
void ConnectedNodes_Added(object sender, NodeEventArgs e)
{
Console.WriteLine("Connected : " + _Group.ConnectedNodes.Count);
}
NodesGroup _Group;
public static bool IsValidSignatureEncoding(byte[] sig)
{
// Format: 0x30 [total-length] 0x02 [R-length] [R] 0x02 [S-length] [S] [sighash]
// * total-length: 1-byte length descriptor of everything that follows,
// excluding the sighash byte.
// * R-length: 1-byte length descriptor of the R value that follows.
// * R: arbitrary-length big-endian encoded R value. It must use the shortest
// possible encoding for a positive integers (which means no null bytes at
// the start, except a single one when the next byte has its highest bit set).
// * S-length: 1-byte length descriptor of the S value that follows.
// * S: arbitrary-length big-endian encoded S value. The same rules apply.
// * sighash: 1-byte value indicating what data is hashed (not part of the DER
// signature)
var signLen = sig.Length;
// Minimum and maximum size constraints.
if(signLen < 9 || signLen > 73)
return false;
// A signature is of type 0x30 (compound).
if(sig[0] != 0x30)
return false;
// Make sure the length covers the entire signature.
if(sig[1] != signLen - 3)
return false;
// Extract the length of the R element.
uint lenR = sig[3];
// Make sure the length of the S element is still inside the signature.
if(5 + lenR >= signLen)
return false;
// Extract the length of the S element.
uint lenS = sig[5 + lenR];
// Verify that the length of the signature matches the sum of the length
// of the elements.
if((lenR + lenS + 7) != signLen)
return false;
// Check whether the R element is an integer.
if(sig[2] != 0x02)
return false;
// Zero-length integers are not allowed for R.
if(lenR == 0)
return false;
// Negative numbers are not allowed for R.
if((sig[4] & 0x80) != 0)
return false;
// Null bytes at the start of R are not allowed, unless R would
// otherwise be interpreted as a negative number.
if(lenR > 1 && (sig[4] == 0x00) && (sig[5] & 0x80) == 0)
return false;
// Check whether the S element is an integer.
if(sig[lenR + 4] != 0x02)
return false;
// Zero-length integers are not allowed for S.
if(lenS == 0)
return false;
// Negative numbers are not allowed for S.
if((sig[lenR + 6] & 0x80) != 0)
return false;
// Null bytes at the start of S are not allowed, unless S would otherwise be
// interpreted as a negative number.
if(lenS > 1 && (sig[lenR + 6] == 0x00) && (sig[lenR + 7] & 0x80) == 0)
return false;
return true;
}
}
}
Let me know if anyone think it is better I stop it.
