示例#1
0
        public List <char> Encrypt(List <char> plain)
        {
            // 拷贝plain
            var copy = new List <char>();

            for (int i = 0; i < plain.Count; i++)
            {
                copy.Add(plain[i]);
            }

            // 将终结符转义,即将一个终结符换成两个连续的终结符
            for (int i = 0; i < copy.Count; i++)
            {
                if (copy[i] == Transfer_Char)
                {
                    copy.Insert(i, Transfer_Char);
                    i++;
                }
            }

            // 在数据的最后加上终结符
            copy.Add(Transfer_Char);

            // 检查数据总长度,如果最后一组数量不够,需要填充数据
            int appendLength = copy.Count % groupLength;// 填充数

            if (appendLength != 0)
            {
                appendLength = groupLength - appendLength;
            }

            for (int i = 0; i < appendLength; i++)
            {
                copy.Add(Append_Char);
            }

            // TODO Delete
            //PrintList(copy, "[加密前]");

            int groupNums = copy.Count / groupLength + ((copy.Count % groupLength) == 0 ? 0 : 1); // 总分组数

            List <char> result = new List <char>();                                               // 结果

            for (int i = 0; i < groupNums; i++)
            {
                // 使用加密矩阵将分组加密,然后添加到结果中
                result.AddRange(MatrixIntGF26.MultiplyMod26(copy.GetRange(i * groupLength, groupLength).ToArray(), EKEY));
            }

            // TODO Delete
            //PrintList(result, "[加密后]");

            return(result);
        }
示例#2
0
        public List <char> Decrypt(List <char> cipher)
        {
            // TODO Delete
            //PrintList(cipher, "[解密前]");

            if (cipher.Count % groupLength != 0)
            {
                throw new FormatException("密文的格式出错,请检查是否缺失数据");
            }

            // 解密
            int         groupNums = cipher.Count / groupLength; // 总分组数
            List <char> result    = new List <char>();          // 结果

            for (int i = 0; i < groupNums; i++)
            {
                // 使用加密矩阵将分组解密,然后添加到结果中
                result.AddRange(MatrixIntGF26.MultiplyMod26(cipher.GetRange(i * groupLength, groupLength).ToArray(), DKEY));
            }

            // TODO Delete
            //PrintList(result, "[解密后]");

            // 去冗余,去除终结符之后的数据
            var index = result.LastIndexOf(Transfer_Char);

            if (index == -1)
            {
                throw new Exception("数据出错,或者数据和希尔密码的密钥不匹配");
            }
            result.RemoveRange(index, result.Count - index);

            // 合并连续的两个终结符
            for (int i = 1; i < result.Count; i++)
            {
                if (result[i] == Transfer_Char)
                {
                    if (result[i - 1] == Transfer_Char)
                    {
                        result.RemoveAt(i);
                    }
                }
            }


            return(result);
        }