// Simple, thoroughly commented implementation of 128-bit AES / Rijndael using C#
// Chris Hulbert - chris.hulbert@gmail.com - http://splinter.com.au/blog - http://github.com/chrishulbert/crypto
using System;

namespace AssetStudio
{
    public static class AES
    {
        static byte[] ShiftRowsTableInv = { 0x00, 0x0D, 0x0A, 0x07, 0x04, 0x01, 0x0E, 0x0B, 0x08, 0x05, 0x02, 0x0F, 0x0C, 0x09, 0x06, 0x03 };
        static byte[] LookupSBoxInv = { 0x52, 0x09, 0x6A, 0xD5, 0x30, 0x36, 0xA5, 0x38, 0xBF, 0x40, 0xA3, 0x9E, 0x81, 0xF3, 0xD7, 0xFB, 0x7C, 0xE3, 0x39, 0x82, 0x9B, 0x2F, 0xFF, 0x87, 0x34, 0x8E, 0x43, 0x44, 0xC4, 0xDE, 0xE9, 0xCB, 0x54, 0x7B, 0x94, 0x32, 0xA6, 0xC2, 0x23, 0x3D, 0xEE, 0x4C, 0x95, 0x0B, 0x42, 0xFA, 0xC3, 0x4E, 0x08, 0x2E, 0xA1, 0x66, 0x28, 0xD9, 0x24, 0xB2, 0x76, 0x5B, 0xA2, 0x49, 0x6D, 0x8B, 0xD1, 0x25, 0x72, 0xF8, 0xF6, 0x64, 0x86, 0x68, 0x98, 0x16, 0xD4, 0xA4, 0x5C, 0xCC, 0x5D, 0x65, 0xB6, 0x92, 0x6C, 0x70, 0x48, 0x50, 0xFD, 0xED, 0xB9, 0xDA, 0x5E, 0x15, 0x46, 0x57, 0xA7, 0x8D, 0x9D, 0x84, 0x90, 0xD8, 0xAB, 0x00, 0x8C, 0xBC, 0xD3, 0x0A, 0xF7, 0xE4, 0x58, 0x05, 0xB8, 0xB3, 0x45, 0x06, 0xD0, 0x2C, 0x1E, 0x8F, 0xCA, 0x3F, 0x0F, 0x02, 0xC1, 0xAF, 0xBD, 0x03, 0x01, 0x13, 0x8A, 0x6B, 0x3A, 0x91, 0x11, 0x41, 0x4F, 0x67, 0xDC, 0xEA, 0x97, 0xF2, 0xCF, 0xCE, 0xF0, 0xB4, 0xE6, 0x73, 0x96, 0xAC, 0x74, 0x22, 0xE7, 0xAD, 0x35, 0x85, 0xE2, 0xF9, 0x37, 0xE8, 0x1C, 0x75, 0xDF, 0x6E, 0x47, 0xF1, 0x1A, 0x71, 0x1D, 0x29, 0xC5, 0x89, 0x6F, 0xB7, 0x62, 0x0E, 0xAA, 0x18, 0xBE, 0x1B, 0xFC, 0x56, 0x3E, 0x4B, 0xC6, 0xD2, 0x79, 0x20, 0x9A, 0xDB, 0xC0, 0xFE, 0x78, 0xCD, 0x5A, 0xF4, 0x1F, 0xDD, 0xA8, 0x33, 0x88, 0x07, 0xC7, 0x31, 0xB1, 0x12, 0x10, 0x59, 0x27, 0x80, 0xEC, 0x5F, 0x60, 0x51, 0x7F, 0xA9, 0x19, 0xB5, 0x4A, 0x0D, 0x2D, 0xE5, 0x7A, 0x9F, 0x93, 0xC9, 0x9C, 0xEF, 0xA0, 0xE0, 0x3B, 0x4D, 0xAE, 0x2A, 0xF5, 0xB0, 0xC8, 0xEB, 0xBB, 0x3C, 0x83, 0x53, 0x99, 0x61, 0x17, 0x2B, 0x04, 0x7E, 0xBA, 0x77, 0xD6, 0x26, 0xE1, 0x69, 0x14, 0x63, 0x55, 0x21, 0x0C, 0x7D };
        static byte[] LookupG9 = { 0x00, 0x09, 0x12, 0x1B, 0x24, 0x2D, 0x36, 0x3F, 0x48, 0x41, 0x5A, 0x53, 0x6C, 0x65, 0x7E, 0x77, 0x90, 0x99, 0x82, 0x8B, 0xB4, 0xBD, 0xA6, 0xAF, 0xD8, 0xD1, 0xCA, 0xC3, 0xFC, 0xF5, 0xEE, 0xE7, 0x3B, 0x32, 0x29, 0x20, 0x1F, 0x16, 0x0D, 0x04, 0x73, 0x7A, 0x61, 0x68, 0x57, 0x5E, 0x45, 0x4C, 0xAB, 0xA2, 0xB9, 0xB0, 0x8F, 0x86, 0x9D, 0x94, 0xE3, 0xEA, 0xF1, 0xF8, 0xC7, 0xCE, 0xD5, 0xDC, 0x76, 0x7F, 0x64, 0x6D, 0x52, 0x5B, 0x40, 0x49, 0x3E, 0x37, 0x2C, 0x25, 0x1A, 0x13, 0x08, 0x01, 0xE6, 0xEF, 0xF4, 0xFD, 0xC2, 0xCB, 0xD0, 0xD9, 0xAE, 0xA7, 0xBC, 0xB5, 0x8A, 0x83, 0x98, 0x91, 0x4D, 0x44, 0x5F, 0x56, 0x69, 0x60, 0x7B, 0x72, 0x05, 0x0C, 0x17, 0x1E, 0x21, 0x28, 0x33, 0x3A, 0xDD, 0xD4, 0xCF, 0xC6, 0xF9, 0xF0, 0xEB, 0xE2, 0x95, 0x9C, 0x87, 0x8E, 0xB1, 0xB8, 0xA3, 0xAA, 0xEC, 0xE5, 0xFE, 0xF7, 0xC8, 0xC1, 0xDA, 0xD3, 0xA4, 0xAD, 0xB6, 0xBF, 0x80, 0x89, 0x92, 0x9B, 0x7C, 0x75, 0x6E, 0x67, 0x58, 0x51, 0x4A, 0x43, 0x34, 0x3D, 0x26, 0x2F, 0x10, 0x19, 0x02, 0x0B, 0xD7, 0xDE, 0xC5, 0xCC, 0xF3, 0xFA, 0xE1, 0xE8, 0x9F, 0x96, 0x8D, 0x84, 0xBB, 0xB2, 0xA9, 0xA0, 0x47, 0x4E, 0x55, 0x5C, 0x63, 0x6A, 0x71, 0x78, 0x0F, 0x06, 0x1D, 0x14, 0x2B, 0x22, 0x39, 0x30, 0x9A, 0x93, 0x88, 0x81, 0xBE, 0xB7, 0xAC, 0xA5, 0xD2, 0xDB, 0xC0, 0xC9, 0xF6, 0xFF, 0xE4, 0xED, 0x0A, 0x03, 0x18, 0x11, 0x2E, 0x27, 0x3C, 0x35, 0x42, 0x4B, 0x50, 0x59, 0x66, 0x6F, 0x74, 0x7D, 0xA1, 0xA8, 0xB3, 0xBA, 0x85, 0x8C, 0x97, 0x9E, 0xE9, 0xE0, 0xFB, 0xF2, 0xCD, 0xC4, 0xDF, 0xD6, 0x31, 0x38, 0x23, 0x2A, 0x15, 0x1C, 0x07, 0x0E, 0x79, 0x70, 0x6B, 0x62, 0x5D, 0x54, 0x4F, 0x46 };
        static byte[] LookupG11 = { 0x00, 0x0B, 0x16, 0x1D, 0x2C, 0x27, 0x3A, 0x31, 0x58, 0x53, 0x4E, 0x45, 0x74, 0x7F, 0x62, 0x69, 0xB0, 0xBB, 0xA6, 0xAD, 0x9C, 0x97, 0x8A, 0x81, 0xE8, 0xE3, 0xFE, 0xF5, 0xC4, 0xCF, 0xD2, 0xD9, 0x7B, 0x70, 0x6D, 0x66, 0x57, 0x5C, 0x41, 0x4A, 0x23, 0x28, 0x35, 0x3E, 0x0F, 0x04, 0x19, 0x12, 0xCB, 0xC0, 0xDD, 0xD6, 0xE7, 0xEC, 0xF1, 0xFA, 0x93, 0x98, 0x85, 0x8E, 0xBF, 0xB4, 0xA9, 0xA2, 0xF6, 0xFD, 0xE0, 0xEB, 0xDA, 0xD1, 0xCC, 0xC7, 0xAE, 0xA5, 0xB8, 0xB3, 0x82, 0x89, 0x94, 0x9F, 0x46, 0x4D, 0x50, 0x5B, 0x6A, 0x61, 0x7C, 0x77, 0x1E, 0x15, 0x08, 0x03, 0x32, 0x39, 0x24, 0x2F, 0x8D, 0x86, 0x9B, 0x90, 0xA1, 0xAA, 0xB7, 0xBC, 0xD5, 0xDE, 0xC3, 0xC8, 0xF9, 0xF2, 0xEF, 0xE4, 0x3D, 0x36, 0x2B, 0x20, 0x11, 0x1A, 0x07, 0x0C, 0x65, 0x6E, 0x73, 0x78, 0x49, 0x42, 0x5F, 0x54, 0xF7, 0xFC, 0xE1, 0xEA, 0xDB, 0xD0, 0xCD, 0xC6, 0xAF, 0xA4, 0xB9, 0xB2, 0x83, 0x88, 0x95, 0x9E, 0x47, 0x4C, 0x51, 0x5A, 0x6B, 0x60, 0x7D, 0x76, 0x1F, 0x14, 0x09, 0x02, 0x33, 0x38, 0x25, 0x2E, 0x8C, 0x87, 0x9A, 0x91, 0xA0, 0xAB, 0xB6, 0xBD, 0xD4, 0xDF, 0xC2, 0xC9, 0xF8, 0xF3, 0xEE, 0xE5, 0x3C, 0x37, 0x2A, 0x21, 0x10, 0x1B, 0x06, 0x0D, 0x64, 0x6F, 0x72, 0x79, 0x48, 0x43, 0x5E, 0x55, 0x01, 0x0A, 0x17, 0x1C, 0x2D, 0x26, 0x3B, 0x30, 0x59, 0x52, 0x4F, 0x44, 0x75, 0x7E, 0x63, 0x68, 0xB1, 0xBA, 0xA7, 0xAC, 0x9D, 0x96, 0x8B, 0x80, 0xE9, 0xE2, 0xFF, 0xF4, 0xC5, 0xCE, 0xD3, 0xD8, 0x7A, 0x71, 0x6C, 0x67, 0x56, 0x5D, 0x40, 0x4B, 0x22, 0x29, 0x34, 0x3F, 0x0E, 0x05, 0x18, 0x13, 0xCA, 0xC1, 0xDC, 0xD7, 0xE6, 0xED, 0xF0, 0xFB, 0x92, 0x99, 0x84, 0x8F, 0xBE, 0xB5, 0xA8, 0xA3 };
        static byte[] LookupG13 = { 0x00, 0x0D, 0x1A, 0x17, 0x34, 0x39, 0x2E, 0x23, 0x68, 0x65, 0x72, 0x7F, 0x5C, 0x51, 0x46, 0x4B, 0xD0, 0xDD, 0xCA, 0xC7, 0xE4, 0xE9, 0xFE, 0xF3, 0xB8, 0xB5, 0xA2, 0xAF, 0x8C, 0x81, 0x96, 0x9B, 0xBB, 0xB6, 0xA1, 0xAC, 0x8F, 0x82, 0x95, 0x98, 0xD3, 0xDE, 0xC9, 0xC4, 0xE7, 0xEA, 0xFD, 0xF0, 0x6B, 0x66, 0x71, 0x7C, 0x5F, 0x52, 0x45, 0x48, 0x03, 0x0E, 0x19, 0x14, 0x37, 0x3A, 0x2D, 0x20, 0x6D, 0x60, 0x77, 0x7A, 0x59, 0x54, 0x43, 0x4E, 0x05, 0x08, 0x1F, 0x12, 0x31, 0x3C, 0x2B, 0x26, 0xBD, 0xB0, 0xA7, 0xAA, 0x89, 0x84, 0x93, 0x9E, 0xD5, 0xD8, 0xCF, 0xC2, 0xE1, 0xEC, 0xFB, 0xF6, 0xD6, 0xDB, 0xCC, 0xC1, 0xE2, 0xEF, 0xF8, 0xF5, 0xBE, 0xB3, 0xA4, 0xA9, 0x8A, 0x87, 0x90, 0x9D, 0x06, 0x0B, 0x1C, 0x11, 0x32, 0x3F, 0x28, 0x25, 0x6E, 0x63, 0x74, 0x79, 0x5A, 0x57, 0x40, 0x4D, 0xDA, 0xD7, 0xC0, 0xCD, 0xEE, 0xE3, 0xF4, 0xF9, 0xB2, 0xBF, 0xA8, 0xA5, 0x86, 0x8B, 0x9C, 0x91, 0x0A, 0x07, 0x10, 0x1D, 0x3E, 0x33, 0x24, 0x29, 0x62, 0x6F, 0x78, 0x75, 0x56, 0x5B, 0x4C, 0x41, 0x61, 0x6C, 0x7B, 0x76, 0x55, 0x58, 0x4F, 0x42, 0x09, 0x04, 0x13, 0x1E, 0x3D, 0x30, 0x27, 0x2A, 0xB1, 0xBC, 0xAB, 0xA6, 0x85, 0x88, 0x9F, 0x92, 0xD9, 0xD4, 0xC3, 0xCE, 0xED, 0xE0, 0xF7, 0xFA, 0xB7, 0xBA, 0xAD, 0xA0, 0x83, 0x8E, 0x99, 0x94, 0xDF, 0xD2, 0xC5, 0xC8, 0xEB, 0xE6, 0xF1, 0xFC, 0x67, 0x6A, 0x7D, 0x70, 0x53, 0x5E, 0x49, 0x44, 0x0F, 0x02, 0x15, 0x18, 0x3B, 0x36, 0x21, 0x2C, 0x0C, 0x01, 0x16, 0x1B, 0x38, 0x35, 0x22, 0x2F, 0x64, 0x69, 0x7E, 0x73, 0x50, 0x5D, 0x4A, 0x47, 0xDC, 0xD1, 0xC6, 0xCB, 0xE8, 0xE5, 0xF2, 0xFF, 0xB4, 0xB9, 0xAE, 0xA3, 0x80, 0x8D, 0x9A, 0x97 };
        static byte[] LookupG14 = { 0x00, 0x0E, 0x1C, 0x12, 0x38, 0x36, 0x24, 0x2A, 0x70, 0x7E, 0x6C, 0x62, 0x48, 0x46, 0x54, 0x5A, 0xE0, 0xEE, 0xFC, 0xF2, 0xD8, 0xD6, 0xC4, 0xCA, 0x90, 0x9E, 0x8C, 0x82, 0xA8, 0xA6, 0xB4, 0xBA, 0xDB, 0xD5, 0xC7, 0xC9, 0xE3, 0xED, 0xFF, 0xF1, 0xAB, 0xA5, 0xB7, 0xB9, 0x93, 0x9D, 0x8F, 0x81, 0x3B, 0x35, 0x27, 0x29, 0x03, 0x0D, 0x1F, 0x11, 0x4B, 0x45, 0x57, 0x59, 0x73, 0x7D, 0x6F, 0x61, 0xAD, 0xA3, 0xB1, 0xBF, 0x95, 0x9B, 0x89, 0x87, 0xDD, 0xD3, 0xC1, 0xCF, 0xE5, 0xEB, 0xF9, 0xF7, 0x4D, 0x43, 0x51, 0x5F, 0x75, 0x7B, 0x69, 0x67, 0x3D, 0x33, 0x21, 0x2F, 0x05, 0x0B, 0x19, 0x17, 0x76, 0x78, 0x6A, 0x64, 0x4E, 0x40, 0x52, 0x5C, 0x06, 0x08, 0x1A, 0x14, 0x3E, 0x30, 0x22, 0x2C, 0x96, 0x98, 0x8A, 0x84, 0xAE, 0xA0, 0xB2, 0xBC, 0xE6, 0xE8, 0xFA, 0xF4, 0xDE, 0xD0, 0xC2, 0xCC, 0x41, 0x4F, 0x5D, 0x53, 0x79, 0x77, 0x65, 0x6B, 0x31, 0x3F, 0x2D, 0x23, 0x09, 0x07, 0x15, 0x1B, 0xA1, 0xAF, 0xBD, 0xB3, 0x99, 0x97, 0x85, 0x8B, 0xD1, 0xDF, 0xCD, 0xC3, 0xE9, 0xE7, 0xF5, 0xFB, 0x9A, 0x94, 0x86, 0x88, 0xA2, 0xAC, 0xBE, 0xB0, 0xEA, 0xE4, 0xF6, 0xF8, 0xD2, 0xDC, 0xCE, 0xC0, 0x7A, 0x74, 0x66, 0x68, 0x42, 0x4C, 0x5E, 0x50, 0x0A, 0x04, 0x16, 0x18, 0x32, 0x3C, 0x2E, 0x20, 0xEC, 0xE2, 0xF0, 0xFE, 0xD4, 0xDA, 0xC8, 0xC6, 0x9C, 0x92, 0x80, 0x8E, 0xA4, 0xAA, 0xB8, 0xB6, 0x0C, 0x02, 0x10, 0x1E, 0x34, 0x3A, 0x28, 0x26, 0x7C, 0x72, 0x60, 0x6E, 0x44, 0x4A, 0x58, 0x56, 0x37, 0x39, 0x2B, 0x25, 0x0F, 0x01, 0x13, 0x1D, 0x47, 0x49, 0x5B, 0x55, 0x7F, 0x71, 0x63, 0x6D, 0xD7, 0xD9, 0xCB, 0xC5, 0xEF, 0xE1, 0xF3, 0xFD, 0xA7, 0xA9, 0xBB, 0xB5, 0x9F, 0x91, 0x83, 0x8D };

        static void SubBytesInv(byte[] a)
        {
            for (int i = 0; i < a.Length; i++)
                a[i] = LookupSBoxInv[a[i]];
        }
        static void XorRoundKey(byte[] state, byte[] keys, int round)
        {
            for (int i = 0; i < 0x10; i++)
                state[i] ^= keys[i + round * 0x10];
        }
        static void ShiftRowsInv(byte[] state)
        {
            byte[] temp = new byte[0x10];
            Array.Copy(state, temp, 0x10);
            for (int i = 0; i < 0x10; i++)
                state[i] = temp[ShiftRowsTableInv[i]];
        }
        static void MixColInv(byte[] state, int off)
        {
            byte a0 = state[off + 0];
            byte a1 = state[off + 1];
            byte a2 = state[off + 2];
            byte a3 = state[off + 3];
            state[off + 0] = (byte)(LookupG14[a0] ^ LookupG9[a3] ^ LookupG13[a2] ^ LookupG11[a1]);
            state[off + 1] = (byte)(LookupG14[a1] ^ LookupG9[a0] ^ LookupG13[a3] ^ LookupG11[a2]);
            state[off + 2] = (byte)(LookupG14[a2] ^ LookupG9[a1] ^ LookupG13[a0] ^ LookupG11[a3]);
            state[off + 3] = (byte)(LookupG14[a3] ^ LookupG9[a2] ^ LookupG13[a1] ^ LookupG11[a0]);
        }
        static void MixColsInv(byte[] state)
        {
            MixColInv(state, 0x00);
            MixColInv(state, 0x04);
            MixColInv(state, 0x08);
            MixColInv(state, 0x0C);
        }
        public static void Decrypt(byte[] m, byte[] keys)
        {
            byte[] c = new byte[0x10];
            Array.Copy(m, c, 0x10);
            XorRoundKey(c, keys, 0);

            for (int i = 0; i < 9; i++)
            {
                SubBytesInv(c);
                ShiftRowsInv(c);
                MixColsInv(c);
                XorRoundKey(c, keys, i + 1);
            }

            SubBytesInv(c);
            ShiftRowsInv(c);
            XorRoundKey(c, keys, 0xA);
            Array.Copy(c, m, 0x10);
        }
    }
}