C#加密解密(DES,AES,Base64,md5,SHA256,RSA,RC4)
2017-12-28 14:48 杨新华 阅读(1862) 评论(0) 编辑 收藏 举报一:异或^简单加解密(数字类型)
1:原理:
异或用于比较两个二进制数的相应位,在执行按位"异或"运算时,如果两个二进制数的相应位都为1或者都为0,则返回0;如果两个二进制数的相应位其中一个为1另一个为0,则返回1.
//对数字加密
int P_int_Num, P_int_Key;//定义两个值类型变量
string Encryptstr = (P_int_Num ^ P_int_Key).ToString();//加密数值
//对数字解密
int P_int_Key, P_int_Encrypt;//定义两个值类型变量
string Encryptstr =(P_int_Encrypt ^ P_int_Key).ToString();//解密数值
二:加密解密类
(DES,AES,Base64,md5,SHA256,RSA,RC4)
public class JiaMiJieMi
{
#region DES对称加密解密
/// <summary> 加密字符串
/// </summary>
/// <param name="strText">需被加密的字符串</param>
/// <param name="strEncrKey">密钥</param>
/// <returns></returns>
public static string DesEncrypt(string strText, string strEncrKey)
{
try
{
byte[] byKey = null;
byte[] IV = { 0x12, 0x34, 0x56, 0x78, 0x90, 0xAB, 0xCD, 0xEF };
byKey = Encoding.UTF8.GetBytes(strEncrKey.Substring(0, 8));
DESCryptoServiceProvider des = new DESCryptoServiceProvider();
byte[] inputByteArray = Encoding.UTF8.GetBytes(strText);
MemoryStream ms = new MemoryStream();
CryptoStream cs = new CryptoStream(ms, des.CreateEncryptor(byKey, IV), CryptoStreamMode.Write);
cs.Write(inputByteArray, 0, inputByteArray.Length);
cs.FlushFinalBlock();
return Convert.ToBase64String(ms.ToArray());
}
catch
{
return "";
}
}
/// <summary> 解密字符串
/// </summary>
/// <param name="strText">需被解密的字符串</param>
/// <param name="sDecrKey">密钥</param>
/// <returns></returns>
public static string DesDecrypt(string strText, string sDecrKey)
{
try
{
byte[] byKey = null;
byte[] IV = { 0x12, 0x34, 0x56, 0x78, 0x90, 0xAB, 0xCD, 0xEF };
byte[] inputByteArray = new Byte[strText.Length];
byKey = Encoding.UTF8.GetBytes(sDecrKey.Substring(0, 8));
DESCryptoServiceProvider des = new DESCryptoServiceProvider();
inputByteArray = Convert.FromBase64String(strText);
MemoryStream ms = new MemoryStream();
CryptoStream cs = new CryptoStream(ms, des.CreateDecryptor(byKey, IV), CryptoStreamMode.Write);
cs.Write(inputByteArray, 0, inputByteArray.Length);
cs.FlushFinalBlock();
Encoding encoding = new UTF8Encoding();
return encoding.GetString(ms.ToArray());
}
catch
{
return null;
}
}
/// <summary> 加密文件
///
/// </summary>
/// <param name="m_InFilePath">原路径</param>
/// <param name="m_OutFilePath">加密后的文件路径</param>
/// <param name="strEncrKey">密钥</param>
public static void DesEncryptFile(string m_InFilePath, string m_OutFilePath, string strEncrKey)
{
try
{
byte[] byKey = null;
byte[] IV = { 0x12, 0x34, 0x56, 0x78, 0x90, 0xAB, 0xCD, 0xEF };
byKey = Encoding.UTF8.GetBytes(strEncrKey.Substring(0, 8));
FileStream fin = new FileStream(m_InFilePath, FileMode.Open, FileAccess.Read);
FileStream fout = new FileStream(m_OutFilePath, FileMode.OpenOrCreate, FileAccess.Write);
fout.SetLength(0);
//Create variables to help with read and write.
byte[] bin = new byte[100]; //This is intermediate storage for the encryption.
long rdlen = 0; //This is the total number of bytes written.
long totlen = fin.Length; //This is the total length of the input file.
int len; //This is the number of bytes to be written at a time.
DES des = new DESCryptoServiceProvider();
CryptoStream encStream = new CryptoStream(fout, des.CreateEncryptor(byKey, IV), CryptoStreamMode.Write);
//Read from the input file, then encrypt and write to the output file.
while (rdlen < totlen)
{
len = fin.Read(bin, 0, 100);
encStream.Write(bin, 0, len);
rdlen = rdlen + len;
}
encStream.Close();
fout.Close();
fin.Close();
}
catch
{
}
}
/// <summary> 解密文件
///
/// </summary>
/// <param name="m_InFilePath">被解密路径</param>
/// <param name="m_OutFilePath">解密后的路径</param>
/// <param name="sDecrKey">密钥</param>
public static void DesDecryptFile(string m_InFilePath, string m_OutFilePath, string sDecrKey)
{
try
{
byte[] byKey = null;
byte[] IV = { 0x12, 0x34, 0x56, 0x78, 0x90, 0xAB, 0xCD, 0xEF };
byKey = Encoding.UTF8.GetBytes(sDecrKey.Substring(0, 8));
FileStream fin = new FileStream(m_InFilePath, FileMode.Open, FileAccess.Read);
FileStream fout = new FileStream(m_OutFilePath, FileMode.OpenOrCreate, FileAccess.Write);
fout.SetLength(0);
//Create variables to help with read and write.
byte[] bin = new byte[100]; //This is intermediate storage for the encryption.
long rdlen = 0; //This is the total number of bytes written.
long totlen = fin.Length; //This is the total length of the input file.
int len; //This is the number of bytes to be written at a time.
DES des = new DESCryptoServiceProvider();
CryptoStream encStream = new CryptoStream(fout, des.CreateDecryptor(byKey, IV), CryptoStreamMode.Write);
//Read from the input file, then encrypt and write to the output file.
while (rdlen < totlen)
{
len = fin.Read(bin, 0, 100);
encStream.Write(bin, 0, len);
rdlen = rdlen + len;
}
encStream.Close();
fout.Close();
fin.Close();
}
catch
{
}
}
#endregion
#region
对称加密算法AES RijndaelManaged加密解密
private static readonly string Default_AES_Key = "@#kim123";
private static byte[] Keys = { 0x41, 0x72, 0x65, 0x79, 0x6F, 0x75, 0x6D, 0x79,
0x53,0x6E, 0x6F, 0x77, 0x6D, 0x61, 0x6E, 0x3F };
public static string AES_Encrypt(string encryptString)
{
return AES_Encrypt(encryptString, Default_AES_Key);
}
public static string AES_Decrypt(string decryptString)
{
return AES_Decrypt(decryptString, Default_AES_Key);
}
/// <summary>对称加密算法AES RijndaelManaged加密(RijndaelManaged（AES）算法是块式加密算法)
///
/// </summary>
/// <param name="encryptString">待加密字符串</param>
/// <param name="encryptKey">加密密钥，须半角字符</param>
/// <returns>加密结果字符串</returns>
public static string AES_Encrypt(string encryptString, string encryptKey)
{
encryptKey = GetSubString(encryptKey, 32, "");
encryptKey = encryptKey.PadRight(32, ' ');
RijndaelManaged rijndaelProvider = new RijndaelManaged();
rijndaelProvider.Key = Encoding.UTF8.GetBytes(encryptKey.Substring(0, 32));
rijndaelProvider.IV = Keys;
ICryptoTransform rijndaelEncrypt = rijndaelProvider.CreateEncryptor();
byte[] inputData = Encoding.UTF8.GetBytes(encryptString);
byte[] encryptedData = rijndaelEncrypt.TransformFinalBlock(inputData, 0, inputData.Length);
return Convert.ToBase64String(encryptedData);
}
/// <summary> 对称加密算法AES RijndaelManaged解密字符串
///
/// </summary>
/// <param name="decryptString">待解密的字符串</param>
/// <param name="decryptKey">解密密钥,和加密密钥相同</param>
/// <returns>解密成功返回解密后的字符串,失败返回空</returns>
public static string AES_Decrypt(string decryptString, string decryptKey)
{
try
{
decryptKey = GetSubString(decryptKey, 32, "");
decryptKey = decryptKey.PadRight(32, ' ');
RijndaelManaged rijndaelProvider = new RijndaelManaged();
rijndaelProvider.Key = Encoding.UTF8.GetBytes(decryptKey);
rijndaelProvider.IV = Keys;
ICryptoTransform rijndaelDecrypt = rijndaelProvider.CreateDecryptor();
byte[] inputData = Convert.FromBase64String(decryptString);
byte[] decryptedData = rijndaelDecrypt.TransformFinalBlock(inputData, 0, inputData.Length);
return Encoding.UTF8.GetString(decryptedData);
}
catch
{
return string.Empty;
}
}
/// <summary>
/// 按字节长度(按字节,一个汉字为2个字节)取得某字符串的一部分
/// </summary>
/// <param name="sourceString">源字符串</param>
/// <param name="length">所取字符串字节长度</param>
/// <param name="tailString">附加字符串(当字符串不够长时，尾部所添加的字符串，一般为"...")</param>
/// <returns>某字符串的一部分</returns>
private static string GetSubString(string sourceString, int length, string tailString)
{
return GetSubString(sourceString, 0, length, tailString);
}
/// <summary>
/// 按字节长度(按字节,一个汉字为2个字节)取得某字符串的一部分
/// </summary>
/// <param name="sourceString">源字符串</param>
/// <param name="startIndex">索引位置，以0开始</param>
/// <param name="length">所取字符串字节长度</param>
/// <param name="tailString">附加字符串(当字符串不够长时，尾部所添加的字符串，一般为"...")</param>
/// <returns>某字符串的一部分</returns>
private static string GetSubString(string sourceString, int startIndex, int length, string tailString)
{
string myResult = sourceString;
//当是日文或韩文时(注:中文的范围:\u4e00 - \u9fa5, 日文在\u0800 - \u4e00, 韩文为\xAC00-\xD7A3)
if (System.Text.RegularExpressions.Regex.IsMatch(sourceString, "[\u0800-\u4e00]+") ||
System.Text.RegularExpressions.Regex.IsMatch(sourceString, "[\xAC00-\xD7A3]+"))
{
//当截取的起始位置超出字段串长度时
if (startIndex >= sourceString.Length)
{
return string.Empty;
}
else
{
return sourceString.Substring(startIndex,
((length + startIndex) > sourceString.Length) ? (sourceString.Length - startIndex) : length);
}
}
//中文字符，如"中国人民abcd123"
if (length <= 0)
{
return string.Empty;
}
byte[] bytesSource = Encoding.Default.GetBytes(sourceString);
//当字符串长度大于起始位置
if (bytesSource.Length > startIndex)
{
int endIndex = bytesSource.Length;
//当要截取的长度在字符串的有效长度范围内
if (bytesSource.Length > (startIndex + length))
{
endIndex = length + startIndex;
}
else
{ //当不在有效范围内时,只取到字符串的结尾
length = bytesSource.Length - startIndex;
tailString = "";
}
int[] anResultFlag = new int[length];
int nFlag = 0;
//字节大于127为双字节字符
for (int i = startIndex; i < endIndex; i++)
{
if (bytesSource[i] > 127)
{
nFlag++;
if (nFlag == 3)
{
nFlag = 1;
}
}
else
{
nFlag = 0;
}
anResultFlag[i] = nFlag;
}
//最后一个字节为双字节字符的一半
if ((bytesSource[endIndex - 1] > 127) && (anResultFlag[length - 1] == 1))
{
length = length + 1;
}
byte[] bsResult = new byte[length];
Array.Copy(bytesSource, startIndex, bsResult, 0, length);
myResult = Encoding.Default.GetString(bsResult);
myResult = myResult + tailString;
return myResult;
}
return string.Empty;
}
/// <summary>
/// 加密文件流
/// </summary>
/// <param name="fs"></param>
/// <returns></returns>
public static CryptoStream AES_EncryptStrream(FileStream fs, string decryptKey)
{
decryptKey = GetSubString(decryptKey, 32, "");
decryptKey = decryptKey.PadRight(32, ' ');
RijndaelManaged rijndaelProvider = new RijndaelManaged();
rijndaelProvider.Key = Encoding.UTF8.GetBytes(decryptKey);
rijndaelProvider.IV = Keys;
ICryptoTransform encrypto = rijndaelProvider.CreateEncryptor();
CryptoStream cytptostreamEncr = new CryptoStream(fs, encrypto, CryptoStreamMode.Write);
return cytptostreamEncr;
}
/// <summary>
/// 解密文件流
/// </summary>
/// <param name="fs"></param>
/// <returns></returns>
public static CryptoStream AES_DecryptStream(FileStream fs, string decryptKey)
{
decryptKey = GetSubString(decryptKey, 32, "");
decryptKey = decryptKey.PadRight(32, ' ');
RijndaelManaged rijndaelProvider = new RijndaelManaged();
rijndaelProvider.Key = Encoding.UTF8.GetBytes(decryptKey);
rijndaelProvider.IV = Keys;
ICryptoTransform Decrypto = rijndaelProvider.CreateDecryptor();
CryptoStream cytptostreamDecr = new CryptoStream(fs, Decrypto, CryptoStreamMode.Read);
return cytptostreamDecr;
}
/// <summary>
/// 对指定文件加密
/// </summary>
/// <param name="InputFile"></param>
/// <param name="OutputFile"></param>
/// <returns></returns>
public static bool AES_EncryptFile(string InputFile, string OutputFile)
{
try
{
string decryptKey = "www.iqidi.com";
FileStream fr = new FileStream(InputFile, FileMode.Open);
FileStream fren = new FileStream(OutputFile, FileMode.Create);
CryptoStream Enfr = AES_EncryptStrream(fren, decryptKey);
byte[] bytearrayinput = new byte[fr.Length];
fr.Read(bytearrayinput, 0, bytearrayinput.Length);
Enfr.Write(bytearrayinput, 0, bytearrayinput.Length);
Enfr.Close();
fr.Close();
fren.Close();
}
catch
{
//文件异常
return false;
}
return true;
}
/// <summary>
/// 对指定的文件解压缩
/// </summary>
/// <param name="InputFile"></param>
/// <param name="OutputFile"></param>
/// <returns></returns>
public static bool AES_DecryptFile(string InputFile, string OutputFile)
{
try
{
string decryptKey = "www.iqidi.com";
FileStream fr = new FileStream(InputFile, FileMode.Open);
FileStream frde = new FileStream(OutputFile, FileMode.Create);
CryptoStream Defr = AES_DecryptStream(fr, decryptKey);
byte[] bytearrayoutput = new byte[1024];
int m_count = 0;
do
{
m_count = Defr.Read(bytearrayoutput, 0, bytearrayoutput.Length);
frde.Write(bytearrayoutput, 0, m_count);
if (m_count < bytearrayoutput.Length)
break;
} while (true);
Defr.Close();
fr.Close();
frde.Close();
}
catch
{
//文件异常
return false;
}
return true;
}
#endregion
#region Base64加密解密
/// <summary>
/// Base64是一種使用64基的位置計數法。它使用2的最大次方來代表僅可列印的ASCII 字元。
/// 這使它可用來作為電子郵件的傳輸編碼。在Base64中的變數使用字元A-Z、a-z和0-9 ，
/// 這樣共有62個字元，用來作為開始的64個數字，最後兩個用來作為數字的符號在不同的
/// 系統中而不同。
/// Base64加密
/// </summary>
/// <param name="str"></param>
/// <returns></returns>
public static string Base64Encrypt(string str)
{
byte[] encbuff = System.Text.Encoding.UTF8.GetBytes(str);
return Convert.ToBase64String(encbuff);
}
/// <summary>
/// Base64解密
/// </summary>
/// <param name="str"></param>
/// <returns></returns>
public static string Base64Decrypt(string str)
{
byte[] decbuff = Convert.FromBase64String(str);
return System.Text.Encoding.UTF8.GetString(decbuff);
}
#endregion
#region md5
/// <summary>
/// 获得32位的MD5加密
/// </summary>
/// <param name="input"></param>
/// <returns></returns>
public static string GetMD5_32(string input)
{
System.Security.Cryptography.MD5 md5 = System.Security.Cryptography.MD5.Create();
byte[] data = md5.ComputeHash(System.Text.Encoding.Default.GetBytes(input));
StringBuilder sb = new StringBuilder();
for (int i = 0; i < data.Length; i++)
{
sb.Append(data[i].ToString("x2"));
}
return sb.ToString();
}
/// <summary>
/// 获得16位的MD5加密
/// </summary>
/// <param name="input"></param>
/// <returns></returns>
public static string GetMD5_16(string input)
{
return GetMD5_32(input).Substring(8, 16);
}
/// <summary>
/// 获得8位的MD5加密
/// </summary>
/// <param name="input"></param>
/// <returns></returns>
public static string GetMD5_8(string input)
{
return GetMD5_32(input).Substring(8, 8);
}
/// <summary>
/// 获得4位的MD5加密
/// </summary>
/// <param name="input"></param>
/// <returns></returns>
public static string GetMD5_4(string input)
{
return GetMD5_32(input).Substring(8, 4);
}
public static string MD5EncryptHash(String input)
{
MD5 md5 = new MD5CryptoServiceProvider();
//the GetBytes method returns byte array equavalent of a string
byte[] res = md5.ComputeHash(Encoding.Default.GetBytes(input), 0, input.Length);
char[] temp = new char[res.Length];
//copy to a char array which can be passed to a String constructor
Array.Copy(res, temp, res.Length);
//return the result as a string
return new String(temp);
}
#endregion
#region MD5签名验证
/// <summary>
/// 对给定文件路径的文件加上标签
/// </summary>
/// <param name="path">要加密的文件的路径</param>
/// <returns>标签的值</returns>
public static bool AddMD5(string path)
{
bool IsNeed = true;
if (CheckMD5(path)) //已进行MD5处理
IsNeed = false;
try
{
FileStream fsread = new FileStream(path, FileMode.Open, FileAccess.Read, FileShare.Read);
byte[] md5File = new byte[fsread.Length];
fsread.Read(md5File, 0, (int)fsread.Length); // 将文件流读取到Buffer中
fsread.Close();
if (IsNeed)
{
string result = MD5Buffer(md5File, 0, md5File.Length); // 对Buffer中的字节内容算MD5
byte[] md5 = System.Text.Encoding.ASCII.GetBytes(result); // 将字符串转换成字节数组以便写人到文件中
FileStream fsWrite = new FileStream(path, FileMode.Open, FileAccess.ReadWrite);
fsWrite.Write(md5File, 0, md5File.Length); // 将文件，MD5值 重新写入到文件中。
fsWrite.Write(md5, 0, md5.Length);
fsWrite.Close();
}
else
{
FileStream fsWrite = new FileStream(path, FileMode.Open, FileAccess.ReadWrite);
fsWrite.Write(md5File, 0, md5File.Length);
fsWrite.Close();
}
}
catch
{
return false;
}
return true;
}
/// <summary>
/// 对给定路径的文件进行验证
/// </summary>
/// <param name="path"></param>
/// <returns>是否加了标签或是否标签值与内容值一致</returns>
public static bool CheckMD5(string path)
{
try
{
FileStream get_file = new FileStream(path, FileMode.Open, FileAccess.Read, FileShare.Read);
byte[] md5File = new byte[get_file.Length]; // 读入文件
get_file.Read(md5File, 0, (int)get_file.Length);
get_file.Close();
string result = MD5Buffer(md5File, 0, md5File.Length - 32); // 对文件除最后32位以外的字节计算MD5，这个32是因为标签位为32位。
string md5 = System.Text.Encoding.ASCII.GetString(md5File, md5File.Length - 32, 32); //读取文件最后32位，其中保存的就是MD5值
return result == md5;
}
catch
{
return false;
}
}
/// <summary>
/// 计算文件的MD5值
/// </summary>
/// <param name="MD5File">MD5签名文件字符数组</param>
/// <param name="index">计算起始位置</param>
/// <param name="count">计算终止位置</param>
/// <returns>计算结果</returns>
private static string MD5Buffer(byte[] MD5File, int index, int count)
{
System.Security.Cryptography.MD5CryptoServiceProvider get_md5 = new System.Security.Cryptography.MD5CryptoServiceProvider();
byte[] hash_byte = get_md5.ComputeHash(MD5File, index, count);
string result = System.BitConverter.ToString(hash_byte);
result = result.Replace("-", "");
return result;
}
#endregion
#region SHA256加密算法
/// <summary>
/// SHA256函数
/// </summary>
/// <param name="str">原始字符串</param>
/// <returns>SHA256结果(返回长度为44字节的字符串)</returns>
public static string SHA256(string str)
{
byte[] SHA256Data = Encoding.UTF8.GetBytes(str);
SHA256Managed Sha256 = new SHA256Managed();
byte[] Result = Sha256.ComputeHash(SHA256Data);
return Convert.ToBase64String(Result); //返回长度为44字节的字符串
}
#endregion
#region
RSA加密 解密
/// <summary>RSA加密
///
/// </summary>
/// <param name="plaintext">明文</param>
/// <param name="publicKey">公钥</param>
/// <returns>密文字符串</returns>
public static string EncryptByRSA(string plaintext, string publicKey)
{
try
{
UnicodeEncoding ByteConverter = new UnicodeEncoding();
byte[] dataToEncrypt = ByteConverter.GetBytes(plaintext);
using (RSACryptoServiceProvider RSA = new RSACryptoServiceProvider())
{
RSA.FromXmlString(publicKey);
byte[] encryptedData = RSA.Encrypt(dataToEncrypt, false);
return Convert.ToBase64String(encryptedData);
}
}
catch (Exception)
{
return null;
}
}
/// <summary> RSA解密
///
/// </summary>
/// <param name="ciphertext">密文</param>
/// <param name="privateKey">私钥</param>
/// <returns>明文字符串</returns>
public static string DecryptByRSA(string ciphertext, string privateKey)
{
try
{
UnicodeEncoding byteConverter = new UnicodeEncoding();
using (RSACryptoServiceProvider RSA = new RSACryptoServiceProvider())
{
RSA.FromXmlString(privateKey);
byte[] encryptedData = Convert.FromBase64String(ciphertext);
byte[] decryptedData = RSA.Decrypt(encryptedData, false);
return byteConverter.GetString(decryptedData);
}
}
catch (Exception)
{
return null;
}
}
/// <summary>生成RSA加密 解密的 密钥
/// 生成的key就是 方法EncryptByRSA与DecryptByRSA用的key了
/// </summary>
/// <param name="path">要生成的密钥文件的路径(文件夹)</param>
public static void getRSAKey(string path)
{
RSACryptoServiceProvider rsa = new RSACryptoServiceProvider();
string datetimestr = System.DateTime.Now.ToString("yyyyMMddHHmmss");
using (StreamWriter writer = new StreamWriter("RSA解密_PrivateKey_" + datetimestr + ".xml")) //这个文件要保密...
{
writer.WriteLine(rsa.ToXmlString(true));
}
using (StreamWriter writer = new StreamWriter("RSA加密_PublicKey_" + datetimestr + ".xml"))
{
writer.WriteLine(rsa.ToXmlString(false));
}
}
#endregion
#region
RC4加密 解密
/// <summary>RC4加密算法
/// 返回进过rc4加密过的字符
/// </summary>
/// <param name="str">被加密的字符</param>
/// <param name="ckey">密钥</param>
public static string EncryptRC4wq(string str, string ckey)
{
int[] s = new int[256];
for (int i = 0; i < 256; i++)
{
s[i] = i;
}
//密钥转数组
char[] keys = ckey.ToCharArray();//密钥转字符数组
int[] key = new int[keys.Length];
for (int i = 0; i < keys.Length; i++)
{
key[i] = keys[i];
}
//明文转数组
char[] datas = str.ToCharArray();
int[] mingwen = new int[datas.Length];
for (int i = 0; i < datas.Length; i++)
{
mingwen[i] = datas[i];
}
//通过循环得到256位的数组(密钥)
int j = 0;
int k = 0;
int length = key.Length;
int a;
for (int i = 0; i < 256; i++)
{
a = s[i];
j = (j + a + key[k]);
if (j >= 256)
{
j = j % 256;
}
s[i] = s[j];
s[j] = a;
if (++k >= length)
{
k = 0;
}
}
//根据上面的256的密钥数组 和 明文得到密文数组
int x = 0, y = 0, a2, b, c;
int length2 = mingwen.Length;
int[] miwen = new int[length2];
for (int i = 0; i < length2; i++)
{
x = x + 1;
x = x % 256;
a2 = s[x];
y = y + a2;
y = y % 256;
s[x] = b = s[y];
s[y] = a2;
c = a2 + b;
c = c % 256;
miwen[i] = mingwen[i] ^ s[c];
}
//密文数组转密文字符
char[] mi = new char[miwen.Length];
for (int i = 0; i < miwen.Length; i++)
{
mi[i] = (char)miwen[i];
}
string miwenstr = new string(mi);
return miwenstr;
}
/// <summary>RC4解密算法
/// 返回进过rc4解密过的字符
/// </summary>
/// <param name="str">被解密的字符</param>
/// <param name="ckey">密钥</param>
public static string DecryptRC4wq(string str, string ckey)
{
int[] s = new int[256];
for (int i = 0; i < 256; i++)
{
s[i] = i;
}
//密钥转数组
char[] keys = ckey.ToCharArray();//密钥转字符数组
int[] key = new int[keys.Length];
for (int i = 0; i < keys.Length; i++)
{
key[i] = keys[i];
}
//密文转数组
char[] datas = str.ToCharArray();
int[] miwen = new int[datas.Length];
for (int i = 0; i < datas.Length; i++)
{
miwen[i] = datas[i];
}
//通过循环得到256位的数组(密钥)
int j = 0;
int k = 0;
int length = key.Length;
int a;
for (int i = 0; i < 256; i++)
{
a = s[i];
j = (j + a + key[k]);
if (j >= 256)
{
j = j % 256;
}
s[i] = s[j];
s[j] = a;
if (++k >= length)
{
k = 0;
}
}
//根据上面的256的密钥数组 和 密文得到明文数组
int x = 0, y = 0, a2, b, c;
int length2 = miwen.Length;
int[] mingwen = new int[length2];
for (int i = 0; i < length2; i++)
{
x = x + 1;
x = x % 256;
a2 = s[x];
y = y + a2;
y = y % 256;
s[x] = b = s[y];
s[y] = a2;
c = a2 + b;
c = c % 256;
mingwen[i] = miwen[i] ^ s[c];
}
//明文数组转明文字符
char[] ming = new char[mingwen.Length];
for (int i = 0; i < mingwen.Length; i++)
{
ming[i] = (char)mingwen[i];
}
string mingwenstr = new string(ming);
return mingwenstr;
}
#endregion
}
