public static bool TryParseProtected(IAead aead, ICipher cipher, MemoryCursor cursor, out InitialPacket result)
{
result = new InitialPacket();
var startOffset = cursor.AsOffset();
var firstByte = PacketFirstByte.Parse(cursor.Peek(1).Span[0]);
if (!firstByte.IsInitialType())
{
return(false);
}
cursor.Move(1);
var version = PacketVersion.Parse(cursor);
var destinationConnectionId = PacketConnectionId.Parse(cursor);
var sourceConnectionId = PacketConnectionId.Parse(cursor);
var token = PacketToken.Parse(cursor);
var payload = PacketPayload.SliceLongProtectedPacketBytes(cursor, aead, cipher, startOffset, firstByte, null, out var packetNumber);
result = new InitialPacket(version,
destinationConnectionId,
sourceConnectionId,
token,
packetNumber,
payload);
return(true);
}
public static PacketPayload.CursorWritingContext StartWriting(MemoryCursor cursor,
PacketVersion version,
PacketConnectionId destinationConnectionId,
PacketConnectionId sourceConnectionId,
PacketNumber packetNumber,
PacketToken token)
{
var startOffset = cursor.AsOffset();
var firstByte = new PacketFirstByte()
.SetInitial()
.SetMaxPacketNumberLength();
firstByte.Write(cursor);
version.WriteBytes(cursor);
destinationConnectionId.WriteBytes(cursor);
sourceConnectionId.WriteBytes(cursor);
token.WriteBytes(cursor);
var context = PacketPayload.StartPacketWriting(cursor, startOffset);
var packetNumberBytes = firstByte.SlicePacketNumberBytes(cursor);
packetNumber.Fill(packetNumberBytes.Span);
return(context);
}
public static bool TryParse(ReadOnlyMemory <byte> bytes, out RetryPacket result)
{
result = new RetryPacket();
if (bytes.IsEmpty)
{
return(false);
}
var firstByte = PacketFirstByte.Parse(bytes.Span[0]);
if (!firstByte.IsRetryType())
{
return(false);
}
var afterFirstByteBytes = bytes.Slice(1);
var version = PacketVersion.Parse(afterFirstByteBytes, out var afterVersionBytes);
var destinationConnectionId = PacketConnectionId.Parse(afterVersionBytes, out var afterDestinationConnectionIdBytes);
var sourceConnectionId = PacketConnectionId.Parse(afterDestinationConnectionIdBytes, out var afterSourceConnectionIdBytes);
var tag = PacketRetryIntegrityTag.Parse(afterSourceConnectionIdBytes, out var beforeTagBytes);
var token = new PacketToken(beforeTagBytes);
result = new RetryPacket(version,
destinationConnectionId,
sourceConnectionId,
token,
tag);
return(true);
}
private RetryPacket(PacketVersion version,
PacketConnectionId destinationConnectionId,
PacketConnectionId sourceConnectionId,
PacketToken retryToken,
PacketRetryIntegrityTag retryIntegrityTag)
{
Version = version;
DestinationConnectionId = destinationConnectionId;
SourceConnectionId = sourceConnectionId;
RetryToken = retryToken;
RetryIntegrityTag = retryIntegrityTag;
}
private InitialPacket(PacketVersion version,
PacketConnectionId destinationConnectionId,
PacketConnectionId sourceConnectionId,
PacketToken token,
PacketNumber number,
MemoryBuffer payload)
{
Version = version;
DestinationConnectionId = destinationConnectionId;
SourceConnectionId = sourceConnectionId;
Token = token;
Number = number;
Payload = payload;
}
public static PacketPayload.LongProtectedWritingContext StartProtectedWriting(IAead aead,
ICipher cipher,
MemoryCursor cursor,
PacketVersion version,
PacketConnectionId destinationConnectionId,
PacketConnectionId sourceConnectionId,
PacketNumber packetNumber,
PacketToken token)
{
var startPacketOffset = cursor.AsOffset();
var firstByte = new PacketFirstByte()
.SetInitial()
.SetMaxPacketNumberLength();
firstByte.Write(cursor);
version.WriteBytes(cursor);
destinationConnectionId.WriteBytes(cursor);
sourceConnectionId.WriteBytes(cursor);
token.WriteBytes(cursor);
return(PacketPayload.StartLongProtectedPacketWriting(cursor, aead, cipher, startPacketOffset, firstByte, packetNumber, null));
}