42 lines
737 B
C#
42 lines
737 B
C#
using Org.BouncyCastle.Security;
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namespace Org.BouncyCastle.Crypto.Paddings;
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public class Pkcs7Padding : IBlockCipherPadding
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{
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public string PaddingName => "PKCS7";
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public void Init(SecureRandom random)
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{
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}
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public int AddPadding(byte[] input, int inOff)
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{
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byte b = (byte)(input.Length - inOff);
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while (inOff < input.Length)
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{
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input[inOff] = b;
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inOff++;
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}
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return b;
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}
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public int PadCount(byte[] input)
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{
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byte b = input[^1];
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int num = b;
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if (num < 1 || num > input.Length)
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{
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throw new InvalidCipherTextException("pad block corrupted");
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}
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for (int i = 2; i <= num; i++)
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{
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if (input[^i] != b)
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{
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throw new InvalidCipherTextException("pad block corrupted");
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}
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}
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return num;
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}
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}
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