PadBlock() [3/3]

int Internal.Cryptography.UniversalCryptoEncryptor.PadBlock ( ReadOnlySpan< byte > block, Span< byte > destination )

inlineprivate

Definition at line 62 of file UniversalCryptoEncryptor.cs.

    {
        int length = block.Length;
        int num = length % base.PaddingSizeBytes;
        int num2 = base.PaddingSizeBytes - num;
        switch (base.PaddingMode)
        {
        case PaddingMode.None:
            if (num != 0)
            {
                throw new CryptographicException(System.SR.Cryptography_PartialBlock);
            }
            if (destination.Length < length)
            {
                throw new ArgumentException(System.SR.Argument_DestinationTooShort, "destination");
            }
            block.CopyTo(destination);
            return length;
        case PaddingMode.ANSIX923:
        {
            int num4 = length + num2;
            if (destination.Length < num4)
            {
                throw new ArgumentException(System.SR.Argument_DestinationTooShort, "destination");
            }
            block.CopyTo(destination);
            destination.Slice(length, num2 - 1).Clear();
            destination[length + num2 - 1] = (byte)num2;
            return num4;
        }
        case PaddingMode.ISO10126:
        {
            int num6 = length + num2;
            if (destination.Length < num6)
            {
                throw new ArgumentException(System.SR.Argument_DestinationTooShort, "destination");
            }
            block.CopyTo(destination);
            RandomNumberGenerator.Fill(destination.Slice(length, num2 - 1));
            destination[length + num2 - 1] = (byte)num2;
            return num6;
        }
        case PaddingMode.PKCS7:
        {
            int num5 = length + num2;
            if (destination.Length < num5)
            {
                throw new ArgumentException(System.SR.Argument_DestinationTooShort, "destination");
            }
            block.CopyTo(destination);
            destination.Slice(length, num2).Fill((byte)num2);
            return num5;
        }
        case PaddingMode.Zeros:
        {
            if (num2 == base.PaddingSizeBytes)
            {
                num2 = 0;
            }
            int num3 = length + num2;
            if (destination.Length < num3)
            {
                throw new ArgumentException(System.SR.Argument_DestinationTooShort, "destination");
            }
            block.CopyTo(destination);
            destination.Slice(length, num2).Clear();
            return num3;
        }
        default:
            throw new CryptographicException(System.SR.Cryptography_UnknownPaddingMode);
        }
    }

References System.SR.Argument_DestinationTooShort, System.ReadOnlySpan< T >.CopyTo(), System.SR.Cryptography_PartialBlock, System.SR.Cryptography_UnknownPaddingMode, System.destination, System.Security.Cryptography.RandomNumberGenerator.Fill(), System.length, and System.ReadOnlySpan< T >.Length.