Example #1
0
        public static byte[] DecryptBCAT(byte[] data, ulong TitleID, string passStr)
        {
            byte[] dec;
            using (MemoryStream ms = new MemoryStream(data))
            {
                BinaryReader br = new BinaryReader(ms);

                //read the magic
                string magic = Encoding.ASCII.GetString(br.ReadBytes(4));
                if (magic != BCAT_MAGIC)
                {
                    throw new Exception("Invalid bcat header!");
                }

                br.BaseStream.Position++; //unknow

                byte crypto      = br.ReadByte();
                byte rsaType     = br.ReadByte();
                byte secretIndex = br.ReadByte();
                br.BaseStream.Position += 8; //padding



                byte[] iv  = br.ReadBytes(0x10);
                byte[] rsa = br.ReadBytes(0x100);
                byte[] enc = br.ReadBytes((int)(br.BaseStream.Length - 0x120));

                if (crypto > 3)
                {
                    return(enc);
                }

                int kSize = (crypto + 1) * 8;

                byte[] salt = Encoding.ASCII.GetBytes(TitleID.ToString("x16") + Program.Config.SaltLower[secretIndex]);
                byte[] pass = Encoding.ASCII.GetBytes(passStr);

                byte[] key = PBKDF2Sha256GetBytes(kSize, pass, salt, 4096);

                dec = AesCrypto.PerformAesCTR(enc, 0, enc.Length, key, iv);
            }
            return(dec);
        }
Example #2
0
        public static byte[] EncryptBCAT(byte[] data, ulong TitleID, string passStr, byte HashType, byte crypto, byte[] signature)
        {
            byte[] output;

            using (MemoryStream ms = new MemoryStream())
            {
                BinaryWriter bw = new BinaryWriter(ms);

                Random rnd = new Random();
                byte[] iv  = new byte[0x10];
                rnd.NextBytes(iv);                 //generate random iv
                int secretIndex = rnd.Next(0, 31); //generate random secret index

                bw.Write(Encoding.ASCII.GetBytes(BCAT_MAGIC));
                bw.Write((byte)1); //must be 1 for some reasons
                bw.Write(crypto);
                bw.Write(HashType);
                bw.Write((byte)secretIndex);
                bw.Write(new byte[8]); //padding
                bw.Write(iv);
                bw.Write(signature);

                if (crypto > 3)
                {
                    bw.Write(data);
                }

                else
                {
                    int    kSize = (crypto + 1) * 8;
                    byte[] salt  = Encoding.ASCII.GetBytes(TitleID.ToString("x16") + Program.Config.SaltLower[secretIndex]);
                    byte[] pass  = Encoding.ASCII.GetBytes(passStr);
                    byte[] key   = PBKDF2Sha256GetBytes(kSize, pass, salt, 4096);
                    bw.Write(AesCrypto.PerformAesCTR(data, 0, data.Length, key, iv));
                }
                output = ms.ToArray();
            }
            return(output);
        }