/// <inheritdoc/>
public Message Decode(
byte[] encoded,
bool reply)
{
if (encoded.Length == 0)
{
throw new ArgumentException("Can't parse empty byte array.");
}
using var stream = new MemoryStream(encoded);
var buffer = new byte[sizeof(int)];
stream.Read(buffer, 0, sizeof(int));
int frameCount = BitConverter.ToInt32(buffer, 0);
var frames = new List <byte[]>();
for (var i = 0; i < frameCount; i++)
{
buffer = new byte[sizeof(int)];
stream.Read(buffer, 0, sizeof(int));
int frameSize = BitConverter.ToInt32(buffer, 0);
buffer = new byte[frameSize];
stream.Read(buffer, 0, frameSize);
frames.Add(buffer);
}
// (reply == true) [version, type, peer, timestamp, sign, frames...]
// (reply == false) [identity, version, type, peer, timestamp, sign, frames...]
List <byte[]> remains = reply ? frames : frames.Skip(1).ToList();
var versionToken = Encoding.ASCII.GetString(remains[(int)Message.MessageFrame.Version]);
AppProtocolVersion remoteVersion = AppProtocolVersion.FromToken(versionToken);
Peer remotePeer;
var dictionary =
(Bencodex.Types.Dictionary)_codec.Decode(remains[(int)Message.MessageFrame.Peer]);
try
{
remotePeer = new BoundPeer(dictionary);
}
catch (KeyNotFoundException)
{
remotePeer = new Peer(dictionary);
}
_messageValidator.ValidateAppProtocolVersion(
remotePeer,
reply ? new byte[] { } : frames[0],
remoteVersion);
var type =
(Message.MessageType)BitConverter.ToInt32(
remains[(int)Message.MessageFrame.Type],
0);
long ticks = BitConverter.ToInt64(remains[(int)Message.MessageFrame.Timestamp], 0);
var timestamp = new DateTimeOffset(ticks, TimeSpan.Zero);
var currentTime = DateTimeOffset.UtcNow;
_messageValidator.ValidateTimestamp(remotePeer, currentTime, timestamp);
byte[] signature = remains[(int)Message.MessageFrame.Sign];
byte[][] body = remains.Skip(Message.CommonFrames).ToArray();
Message message = CreateMessage(type, body);
message.Version = remoteVersion;
message.Remote = remotePeer;
message.Timestamp = timestamp;
var headerWithoutSign = new[]
{
remains[(int)Message.MessageFrame.Version],
remains[(int)Message.MessageFrame.Type],
remains[(int)Message.MessageFrame.Peer],
remains[(int)Message.MessageFrame.Timestamp],
};
var messageToVerify = headerWithoutSign.Concat(body).Aggregate(
new byte[] { },
(arr, bytes) => arr.Concat(bytes).ToArray());
if (!remotePeer.PublicKey.Verify(messageToVerify, signature))
{
throw new InvalidMessageSignatureException(
"The signature of an encoded message is invalid.",
remotePeer,
remotePeer.PublicKey,
messageToVerify,
signature);
}
if (!reply)
{
message.Identity = frames[0];
}
return(message);
}
/// <inheritdoc/>
public Message Decode(
NetMQMessage encoded,
bool reply)
{
if (encoded.FrameCount == 0)
{
throw new ArgumentException("Can't parse empty NetMQMessage.");
}
// (reply == true) [version, type, peer, timestamp, sign, frames...]
// (reply == false) [identity, version, type, peer, timestamp, sign, frames...]
NetMQFrame[] remains = reply ? encoded.ToArray() : encoded.Skip(1).ToArray();
var versionToken = remains[(int)Message.MessageFrame.Version].ConvertToString();
AppProtocolVersion remoteVersion = AppProtocolVersion.FromToken(versionToken);
Peer remotePeer;
var dictionary =
(Bencodex.Types.Dictionary)_codec.Decode(
remains[(int)Message.MessageFrame.Peer].ToByteArray());
try
{
remotePeer = new BoundPeer(dictionary);
}
catch (KeyNotFoundException)
{
remotePeer = new Peer(dictionary);
}
_messageValidator.ValidateAppProtocolVersion(
remotePeer,
reply ? new byte[] { } : encoded[0].ToByteArray(),
remoteVersion);
var type =
(Message.MessageType)remains[(int)Message.MessageFrame.Type].ConvertToInt32();
var ticks = remains[(int)Message.MessageFrame.Timestamp].ConvertToInt64();
var timestamp = new DateTimeOffset(ticks, TimeSpan.Zero);
var currentTime = DateTimeOffset.UtcNow;
_messageValidator.ValidateTimestamp(remotePeer, currentTime, timestamp);
byte[] signature = remains[(int)Message.MessageFrame.Sign].ToByteArray();
NetMQFrame[] body = remains.Skip(Message.CommonFrames)
.ToArray();
Message message = CreateMessage(
type,
body.Select(frame => frame.ToByteArray()).ToArray());
message.Version = remoteVersion;
message.Remote = remotePeer;
message.Timestamp = timestamp;
var headerWithoutSign = new[]
{
remains[(int)Message.MessageFrame.Version],
remains[(int)Message.MessageFrame.Type],
remains[(int)Message.MessageFrame.Peer],
remains[(int)Message.MessageFrame.Timestamp],
};
var messageToVerify = headerWithoutSign.Concat(body).ToByteArray();
if (!remotePeer.PublicKey.Verify(messageToVerify, signature))
{
throw new InvalidMessageSignatureException(
"The signature of an encoded message is invalid.",
remotePeer,
remotePeer.PublicKey,
messageToVerify,
signature);
}
if (!reply)
{
message.Identity = encoded[0].Buffer.ToArray();
}
return(message);
}