implement parsing of headers with different connection ID lengths

internal/protocol/connection_id.go

@@ -12,7 +12,7 @@ type ConnectionID []byte
 
 // GenerateConnectionID generates a connection ID using cryptographic random
 func GenerateConnectionID() (ConnectionID, error) {
-	b := make([]byte, ConnectionIDLen)
+	b := make([]byte, ConnectionIDLenGQUIC)
 	if _, err := rand.Read(b); err != nil {
 		return nil, err
 	}

internal/protocol/protocol.go

@@ -82,3 +82,9 @@ const MinInitialPacketSize = 1200
 // * one failure due to an incorrect or missing source-address token
 // * one failure due the server's certificate chain being unavailable and the server being unwilling to send it without a valid source-address token
 const MaxClientHellos = 3
+
+// ConnectionIDLenGQUIC is the length of the source Connection ID used on gQUIC QUIC packets.
+const ConnectionIDLenGQUIC = 8
+
+// MinConnectionIDLenInitial is the minimum length of the destination connection ID on an Initial packet.
+const MinConnectionIDLenInitial = 8

internal/protocol/server_parameters.go

@@ -145,12 +145,3 @@ const MaxAckFrameSize ByteCount = 1000
 // If the packet packing frequency is higher, multiple packets might be sent at once.
 // Example: For a packet pacing delay of 20 microseconds, we would send 5 packets at once, wait for 100 microseconds, and so forth.
 const MinPacingDelay time.Duration = 100 * time.Microsecond
-
-// ConnectionIDLen is the length of the source Connection ID used on IETF QUIC packets.
-// The Short Header contains the connection ID, but not the length,
-// so we need to know this value in advance (or encode it into the connection ID).
-// TODO: make this configurable
-const ConnectionIDLen = 8
-
-// MinConnectionIDLenInitial is the minimum length of the destination connection ID on an Initial packet.
-const MinConnectionIDLenInitial = 8