public KeyExchangeMessage(UInt32 messageVersion, UInt32 sequence, UInt32 flags,
ECPublicKey baseKey, byte[] baseKeySignature,
ECPublicKey ratchetKey,
IdentityKey identityKey)
{
MaxVersion = CiphertextMessage.CURRENT_VERSION;
Version = messageVersion;
Sequence = sequence;
Flags = flags;
BaseKey = baseKey;
BaseKeySignature = baseKeySignature;
RatchetKey = ratchetKey;
IdentityKey = identityKey;
byte[] version = { ByteUtil.IntsToByteHighAndLow(Version, MaxVersion) };
var keyExchangeMsg = new WhisperProtos.KeyExchangeMessage {
id = (Sequence << 5) | Flags,
baseKey = BaseKey.Serialize(),
ratchetKey = RatchetKey.Serialize(),
identityKey = IdentityKey.Serialize()
};
if(Version >= 3)
{
keyExchangeMsg.baseKeySignature = BaseKeySignature;
}
byte[] bytes;
using(var stream = new MemoryStream())
{
Serializer.Serialize(stream, keyExchangeMsg);
bytes = stream.ToArray();
}
_serialized = ByteUtil.Combine(version, bytes);
}
public KeyExchangeMessage(byte[] serialized)
{
try
{
byte[][] parts = ByteUtil.split(serialized, 1, serialized.Length - 1);
this.version = (uint)ByteUtil.highBitsToInt(parts[0][0]);
this.supportedVersion = (uint)ByteUtil.lowBitsToInt(parts[0][0]);
if (this.version <= CiphertextMessage.UNSUPPORTED_VERSION)
{
throw new LegacyMessageException("Unsupported legacy version: " + this.version);
}
if (this.version > CiphertextMessage.CURRENT_VERSION)
{
throw new InvalidVersionException("Unknown version: " + this.version);
}
WhisperProtos.KeyExchangeMessage message = WhisperProtos.KeyExchangeMessage.ParseFrom(parts[1]);
if (!message.HasId || !message.HasBaseKey ||
!message.HasRatchetKey || !message.HasIdentityKey ||
(this.version >= 3 && !message.HasBaseKeySignature))
{
throw new InvalidMessageException("Some required fields missing!");
}
this.sequence = message.Id >> 5;
this.flags = message.Id & 0x1f;
this.serialized = serialized;
this.baseKey = Curve.decodePoint(message.BaseKey.ToByteArray(), 0);
this.baseKeySignature = message.BaseKeySignature.ToByteArray();
this.ratchetKey = Curve.decodePoint(message.RatchetKey.ToByteArray(), 0);
this.identityKey = new IdentityKey(message.IdentityKey.ToByteArray(), 0);
}
catch (InvalidKeyException e)
{
throw new InvalidMessageException(e);
}
}