moved bin 8 out and removed clientctx

moved crypto bin8 out of entrance server

removed unused clientctx

missed import

fix accidental commit and rename ack_helpers

network/crypto/bin8/bin8_crypto.go

@@ -0,0 +1,51 @@
+package bin8
+
+import (
+	"encoding/binary"
+)
+
+var (
+	_bin8Key     = []byte{0x01, 0x23, 0x34, 0x45, 0x56, 0xAB, 0xCD, 0xEF}
+	_sum32Table0 = []byte{0x35, 0x7A, 0xAA, 0x97, 0x53, 0x66, 0x12}
+	_sum32Table1 = []byte{0x7A, 0xAA, 0x97, 0x53, 0x66, 0x12, 0xDE, 0xDE, 0x35}
+)
+
+// CalcSum32 calculates the custom MHF "sum32" checksum of the given data.
+func CalcSum32(data []byte) uint32 {
+	tableIdx0 := (len(data) + 1) & 0xFF
+	tableIdx1 := int((data[len(data)>>1] + 1) & 0xFF)
+	out := make([]byte, 4)
+	for i := 0; i < len(data); i++ {
+		key := data[i] ^ _sum32Table0[(tableIdx0+i)%7] ^ _sum32Table1[(tableIdx1+i)%9]
+		out[i&3] = (out[i&3] + key) & 0xFF
+	}
+	return binary.BigEndian.Uint32(out)
+}
+
+func rotate(k *uint32) {
+	*k = uint32(((54323 * uint(*k)) + 1) & 0xFFFFFFFF)
+}
+
+// EncryptBin8 encrypts the given data using MHF's "binary8" encryption.
+func EncryptBin8(data []byte, key byte) []byte {
+	_key := uint32(key)
+	var output []byte
+	for i := 0; i < len(data); i++ {
+		rotate(&_key)
+		tmp := _bin8Key[i&7] ^ byte((_key>>13)&0xFF)
+		output = append(output, data[i]^tmp)
+	}
+	return output
+}
+
+// DecryptBin8 decrypts the given MHF "binary8" data.
+func DecryptBin8(data []byte, key byte) []byte {
+	_key := uint32(key)
+	var output []byte
+	for i := 0; i < len(data); i++ {
+		rotate(&_key)
+		tmp := data[i] ^ byte((_key>>13)&0xFF)
+		output = append(output, tmp^_bin8Key[i&7])
+	}
+	return output
+}