Message
Base class for all SSH protocol messages.
using Renci.SshNet.Abstractions;
using Renci.SshNet.Common;
using Renci.SshNet.Compression;
using System.IO;
namespace Renci.SshNet.Messages
{
public abstract class Message : SshData
{
public abstract string MessageName { get; }
public abstract byte MessageNumber { get; }
protected override int BufferCapacity => 1;
protected override void WriteBytes(SshDataStream stream)
{
stream.WriteByte(MessageNumber);
base.WriteBytes(stream);
}
internal byte[] GetPacket(byte paddingMultiplier, Compressor compressor, bool isEncryptThenMAC = false)
{
int bufferCapacity = BufferCapacity;
if (bufferCapacity == -1 || compressor != null) {
using (SshDataStream sshDataStream = new SshDataStream(64)) {
sshDataStream.Seek(9, SeekOrigin.Begin);
if (compressor != null) {
using (SshDataStream sshDataStream2 = new SshDataStream((bufferCapacity != -1) ? bufferCapacity : 64)) {
WriteBytes(sshDataStream2);
byte[] array = compressor.Compress(sshDataStream2.ToArray());
sshDataStream.Write(array, 0, array.Length);
}
} else
WriteBytes(sshDataStream);
bufferCapacity = (int)sshDataStream.Length - 9;
int num = bufferCapacity + 4 + 1;
byte paddingLength = GetPaddingLength(paddingMultiplier, isEncryptThenMAC ? (num - 4) : num);
byte[] array2 = new byte[paddingLength];
CryptoAbstraction.GenerateRandom(array2);
sshDataStream.Write(array2, 0, paddingLength);
uint packetDataLength = GetPacketDataLength(bufferCapacity, paddingLength);
sshDataStream.Seek(4, SeekOrigin.Begin);
sshDataStream.Write(packetDataLength);
sshDataStream.WriteByte(paddingLength);
return sshDataStream.ToArray();
}
}
int num2 = bufferCapacity + 4 + 1;
byte paddingLength2 = GetPaddingLength(paddingMultiplier, isEncryptThenMAC ? (num2 - 4) : num2);
uint packetDataLength2 = GetPacketDataLength(bufferCapacity, paddingLength2);
using (SshDataStream sshDataStream3 = new SshDataStream(num2 + paddingLength2 + 4)) {
sshDataStream3.Seek(4, SeekOrigin.Begin);
sshDataStream3.Write(packetDataLength2);
sshDataStream3.WriteByte(paddingLength2);
WriteBytes(sshDataStream3);
byte[] array3 = new byte[paddingLength2];
CryptoAbstraction.GenerateRandom(array3);
sshDataStream3.Write(array3, 0, paddingLength2);
return sshDataStream3.ToArray();
}
}
private static uint GetPacketDataLength(int messageLength, byte paddingLength)
{
return (uint)(messageLength + paddingLength + 1);
}
private static byte GetPaddingLength(byte paddingMultiplier, long packetLength)
{
byte b = (byte)(-packetLength & (paddingMultiplier - 1));
if (b < paddingMultiplier)
b = (byte)(b + paddingMultiplier);
return b;
}
public override string ToString()
{
return MessageName;
}
internal abstract void Process(Session session);
}
}