private static bool TryGetNanoAlgorithm(ICMAC referent, int macSize, out ICMAC algorithm)
{
if (macSize == -1)
{
algorithm = referent;
return(true);
}
else if (macSize == referent.BlockSize)
{
algorithm = referent;
return(true);
}
else if (macSize >= 8 && macSize <= referent.BlockSize && macSize % 8 == 0)
{
algorithm = new CMAC(((CMAC)referent).BlockAlgorithm, macSize);
return(true);
}
else
{
algorithm = null;
return(false);
}
}
/// <summary>
/// Try get algorithm from mechanism.
/// <para/>Legal algorithm's block size 64 or 128 bits.
/// <para/>Legal mac size is between 8 and block size (8 bits increments).
/// <para/>Used block size as mac size by default.
/// </summary>
/// <param name="mechanism">Algorithm mechanism.</param>
/// <param name="macSize">MAC size bits.</param>
/// <param name="algorithm">Algorithm.</param>
/// <returns></returns>
public static bool TryGetAlgorithm(string mechanism, int macSize, out ICMAC algorithm)
{
mechanism = mechanism.Replace('_', '-').ToUpperInvariant();
if (mechanism.EndsWith("CMAC"))
{
if (mechanism.EndsWith("/CMAC") || mechanism.EndsWith("-CMAC"))
{
mechanism = mechanism.Substring(0, mechanism.Length - 5);
}
else
{
mechanism = mechanism.Substring(0, mechanism.Length - 4);
}
}
mechanism = mechanism.Replace('/', '-');
switch (mechanism)
{
case "AES": return(TryGetNanoAlgorithm(AES_CMAC, macSize, out algorithm));
case "BLOWFISH": return(TryGetNanoAlgorithm(Blowfish_CMAC, macSize, out algorithm));
case "CAMELLIA": return(TryGetNanoAlgorithm(Camellia_CMAC, macSize, out algorithm));
case "CAST5": return(TryGetNanoAlgorithm(CAST5_CMAC, macSize, out algorithm));
case "CAST6": return(TryGetNanoAlgorithm(CAST6_CMAC, macSize, out algorithm));
case "DES": return(TryGetNanoAlgorithm(DES_CMAC, macSize, out algorithm));
case "DESEDE":
case "DESEDE3":
case "TDEA":
case "TRIPLEDES":
case "3DES": return(TryGetNanoAlgorithm(DESede_CMAC, macSize, out algorithm));
case "DSTU7624-128": return(TryGetNanoAlgorithm(DSTU7624_128_CMAC, macSize, out algorithm));
case "GOST28147": return(TryGetNanoAlgorithm(GOST28147_CMAC, macSize, out algorithm));
case "IDEA": return(TryGetNanoAlgorithm(IDEA_CMAC, macSize, out algorithm));
case "NOEKEON": return(TryGetNanoAlgorithm(Noekeon_CMAC, macSize, out algorithm));
case "RC2": return(TryGetNanoAlgorithm(RC2_CMAC, macSize, out algorithm));
case "RC5":
case "RC5-32": return(TryGetNanoAlgorithm(RC5_CMAC, macSize, out algorithm));
case "RC5-64": return(TryGetNanoAlgorithm(RC5_64_CMAC, macSize, out algorithm));
case "RC6": return(TryGetNanoAlgorithm(RC6_CMAC, macSize, out algorithm));
case "RIJNDAEL-128":
case "RIJNDAEL128": return(TryGetNanoAlgorithm(Rijndael_128_CMAC, macSize, out algorithm));
case "SEED": return(TryGetNanoAlgorithm(SEED_CMAC, macSize, out algorithm));
case "SERPENT": return(TryGetNanoAlgorithm(Serpent_CMAC, macSize, out algorithm));
case "SKIPJACK": return(TryGetNanoAlgorithm(SKIPJACK_CMAC, macSize, out algorithm));
case "SM4": return(TryGetNanoAlgorithm(SM4_CMAC, macSize, out algorithm));
case "TEA": return(TryGetNanoAlgorithm(TEA_CMAC, macSize, out algorithm));
case "TNEPRES": return(TryGetNanoAlgorithm(Tnepres_CMAC, macSize, out algorithm));
case "TWOFISH": return(TryGetNanoAlgorithm(Twofish_CMAC, macSize, out algorithm));
case "XTEA": return(TryGetNanoAlgorithm(XTEA_CMAC, macSize, out algorithm));
default: algorithm = null; return(false);
}
}
/// <summary>
/// Try get algorithm from mechanism.
/// <para/>Legal algorithm's block size 64 or 128 bits.
/// <para/>Legal mac size is between 8 and block size (8 bits increments).
/// <para/>Used block size as mac size by default.
/// </summary>
/// <param name="mechanism">Algorithm mechanism.</param>
/// <param name="algorithm">Algorithm.</param>
/// <returns></returns>
public static bool TryGetAlgorithm(string mechanism, out ICMAC algorithm)
{
return(TryGetAlgorithm(mechanism, -1, out algorithm));
}
