Exemplo n.º 1
0
        const byte PrefixByteUknown = 23 << 3; // Base32-encodes to 'X...'

        /// <summary>
        /// Decodes a base 32 encoded NKey into a nkey seed and verifies the checksum.
        /// </summary>
        /// <param name="src">Base 32 encoded Nkey.</param>
        /// <returns></returns>
        public static byte[] Decode(string src)
        {
            byte[] raw = Base32.Decode(src);
            ushort crc = (ushort)(raw[raw.Length - 2] | raw[raw.Length - 1] << 8);

            // trim off the CRC16
            int len = raw.Length - 2;

            byte[] data = new byte[len];
            Buffer.BlockCopy(raw, 0, data, 0, len);

            if (crc != Crc16.Checksum(data))
            {
                throw new NATSException("Invalid CRC");
            }

            return(data);
        }
Exemplo n.º 2
0
        internal static string Encode(byte prefixbyte, bool seed, byte[] src)
        {
            if (!IsValidPublicPrefixByte(prefixbyte))
            {
                throw new NATSException("Invalid prefix");
            }

            if (src.Length != 32)
            {
                throw new NATSException("Invalid seed size");
            }

            MemoryStream stream = new MemoryStream();

            if (seed)
            {
                // In order to make this human printable for both bytes, we need to do a little
                // bit manipulation to setup for base32 encoding which takes 5 bits at a time.
                byte b1 = (byte)(PrefixByteSeed | (prefixbyte >> 5));
                byte b2 = (byte)((prefixbyte & 31) << 3);  // 31 = 00011111

                stream.WriteByte(b1);
                stream.WriteByte(b2);
            }
            else
            {
                stream.WriteByte(prefixbyte);
            }

            // write payload
            stream.Write(src, 0, src.Length);

            // Calculate and write crc16 checksum
            byte[] checksum = BitConverter.GetBytes(Crc16.Checksum(stream.ToArray()));
            stream.Write(checksum, 0, checksum.Length);

            return(Base32.Encode(stream.ToArray()));
        }