DES算法源代码

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DES加密算法代码

DES加密算法代码```pythonimport base64from Crypto.Cipher import DESdef pad(text):while len(text) % 8 != 0:text += ' 'return textdef encrypt(key, text):des = DES.new(key, DES.MODE_ECB)padded_text = pad(text)encrypted_text = des.encrypt(padded_text.encode() return base64.b64encode(encrypted_text).decodedef decrypt(key, encrypted_text):des = DES.new(key, DES.MODE_ECB)decrypted_text =des.decrypt(base64.b64decode(encrypted_text)).decode return decrypted_text.rstripif __name__ == '__main__':key = b'secretkey' # 8字节密钥plaintext = 'Hello, World!'encrypted_text = encrypt(key, plaintext)print('Encrypted text:', encrypted_text)decrypted_text = decrypt(key, encrypted_text)print('Decrypted text:', decrypted_text)```在上述代码中，我们首先导入了`base64`和`Crypto.Cipher`模块，用于进行编码和DES加密操作。

然后定义了两个辅助函数：`pad`用于填充文本，保证其长度能够被8整除；`encrypt`用于进行DES加密操作；`decrypt`用于进行DES解密操作。

DES子密钥生成算法DES加密算法源代码

DES子密钥生成算法DES加密算法源代码下面是一个Java实现的DES密钥生成算法和DES加密算法的源代码示例：```import javax.crypto.Cipher;import javax.crypto.KeyGenerator;import javax.crypto.SecretKey;import javax.crypto.spec.SecretKeySpec;import java.security.NoSuchAlgorithmException;import java.security.SecureRandom;import java.util.Base64;public class DESExamplepublic static void main(String[] args)try//生成DES密钥SecretKey secretKey = generateDESKey(;System.out.println("生成的DES密钥：" +Base64.getEncoder(.encodeToString(secretKey.getEncoded());//加密String plainText = "Hello, World!";byte[] encryptedText = encrypt(plainText, secretKey);System.out.println("加密后的数据：" +Base64.getEncoder(.encodeToString(encryptedText));//解密byte[] decryptedText = decrypt(encryptedText, secretKey);System.out.println("解密后的数据：" + newString(decryptedText));} catch (Exception e)e.printStackTrace(;}}//生成DES密钥public static SecretKey generateDESKey( throws NoSuchAlgorithmExceptionKeyGenerator keyGenerator = KeyGenerator.getInstance("DES");SecureRandom secureRandom = new SecureRandom(;keyGenerator.init(secureRandom);return keyGenerator.generateKey(;}//加密数据public static byte[] encrypt(String plainText, SecretKey secretKey) throws ExceptionCipher cipher = Cipher.getInstance("DES");cipher.init(Cipher.ENCRYPT_MODE, secretKey);return cipher.doFinal(plainText.getBytes();}//解密数据public static byte[] decrypt(byte[] cipherText, SecretKey secretKey) throws ExceptionCipher cipher = Cipher.getInstance("DES");cipher.init(Cipher.DECRYPT_MODE, secretKey);return cipher.doFinal(cipherText);}```该代码中使用了Java的标准库javax.crypto来实现DES密钥生成和DES加密解密操作。

DES算法的C语言实现

DES算法的C语⾔实现利⽤C语⾔实现DES算法，分组密码原理过程很简单，但是在写的过程中检查了好久才发现错误原因，主要有两点：1.在加密过程16轮迭代过程中，最后⼀轮迭代运算后的结果并没有进⾏交换，即C=IP-1（R16，L16），这样做的⽬的是为了加密解密使⽤同⼀个算法2.在S盒的过程中，移位后应该加括号，否则+的优先级⾼于<<,会出错，下⾯是算法源码：1 #include "des.h"2 #include <stdio.h>3 #include <stdlib.h>45const unsigned char IP_table[64] = {658, 50, 42, 34, 26, 18, 10, 2,760, 52, 44, 36, 28, 20, 12, 4,862, 54, 46, 38, 30, 22, 14, 6,964, 56, 48, 40, 32, 24, 16, 8,1057, 49, 41, 33, 25, 17, 9, 1,1159, 51, 43, 35, 27, 19, 11, 3,1261, 53, 45, 37, 29, 21, 13, 5,1363, 55, 47, 39, 31, 23, 15, 714 };1516const unsigned char IPR_table[64] = {1740, 8, 48, 16, 56, 24, 64, 32,1839, 7, 47, 15, 55, 23, 63, 31,1938, 6, 46, 14, 54, 22, 62, 30,2037, 5, 45, 13, 53, 21, 61, 29,2136, 4, 44, 12, 52, 20, 60, 28,2235, 3, 43, 11, 51, 19, 59, 27,2334, 2, 42, 10, 50, 18, 58, 26,2433, 1, 41, 9, 49, 17, 57, 2525 };2627const unsigned char E_table[48] = {2832, 1, 2, 3, 4, 5,294, 5, 6, 7, 8, 9,308, 9, 10, 11, 12, 13,3112, 13, 14, 15, 16, 17,3216, 17, 18, 19, 20, 21,3320, 21, 22, 23, 24, 25,3424, 25, 26, 27, 28, 29,3528, 29, 30, 31, 32, 136 };3738const unsigned char P_table[32] = {3916, 7, 20, 21, 29, 12, 28, 17,401, 15, 23, 26, 5, 18, 31, 10,412, 8, 24, 14, 32, 27, 3, 9,4219, 13, 30, 6, 22, 11, 4, 2543 };4445const unsigned char PC1_table[56] = {4657, 49, 41, 33, 25, 17, 9,471, 58, 50, 42, 34, 26, 18,4810, 2, 59, 51, 43, 35, 27,4919, 11, 3, 60, 52, 44, 36,5063, 55, 47, 39, 31, 23, 15,517, 62, 54, 46, 38, 30, 22,5214, 6, 61, 53, 45, 37, 29,5321, 13, 5, 28, 20, 12, 454 };5556const unsigned char LOOP_table[16] = {571, 1, 2, 2, 2, 2, 2, 2, 1, 2, 2, 2, 2, 2, 2, 158 };5960const unsigned char PC2_table[48] = {6114, 17, 11, 24, 1, 5,623, 28, 15, 6, 21, 10,6323, 19, 12, 4, 26, 8,6416, 7, 27, 20, 13, 2,6541, 52, 31, 37, 47, 55,6630, 40, 51, 45, 33, 48,6744, 49, 39, 56, 34, 53,6846, 42, 50, 36, 29, 3269 };7071const unsigned char sbox[8][4][16] = {72// S17314, 4, 13, 1, 2, 15, 11, 8, 3, 10, 6, 12, 5, 9, 0, 7,740, 15, 7, 4, 14, 2, 13, 1, 10, 6, 12, 11, 9, 5, 3, 8,754, 1, 14, 8, 13, 6, 2, 11, 15, 12, 9, 7, 3, 10, 5, 0,7615, 12, 8, 2, 4, 9, 1, 7, 5, 11, 3, 14, 10, 0, 6, 13,77//S27815, 1, 8, 14, 6, 11, 3, 4, 9, 7, 2, 13, 12, 0, 5, 10,793, 13, 4, 7, 15, 2, 8, 14, 12, 0, 1, 10, 6, 9, 11, 5,800, 14, 7, 11, 10, 4, 13, 1, 5, 8, 12, 6, 9, 3, 2, 15,8113, 8, 10, 1, 3, 15, 4, 2, 11, 6, 7, 12, 0, 5, 14, 9,82//S38310, 0, 9, 14, 6, 3, 15, 5, 1, 13, 12, 7, 11, 4, 2, 8,8413, 7, 0, 9, 3, 4, 6, 10, 2, 8, 5, 14, 12, 11, 15, 1,8513, 6, 4, 9, 8, 15, 3, 0, 11, 1, 2, 12, 5, 10, 14, 7,861, 10, 13, 0, 6, 9, 8, 7, 4, 15, 14, 3, 11, 5, 2, 12,87//S4887, 13, 14, 3, 0, 6, 9, 10, 1, 2, 8, 5, 11, 12, 4, 15,8913, 8, 11, 5, 6, 15, 0, 3, 4, 7, 2, 12, 1, 10, 14, 9,9010, 6, 9, 0, 12, 11, 7, 13, 15, 1, 3, 14, 5, 2, 8, 4,913, 15, 0, 6, 10, 1, 13, 8, 9, 4, 5, 11, 12, 7, 2, 14,92//S5932, 12, 4, 1, 7, 10, 11, 6, 8, 5, 3, 15, 13, 0, 14, 9,9414, 11, 2, 12, 4, 7, 13, 1, 5, 0, 15, 10, 3, 9, 8, 6,954, 2, 1, 11, 10, 13, 7, 8, 15, 9, 12, 5, 6, 3, 0, 14,9611, 8, 12, 7, 1, 14, 2, 13, 6, 15, 0, 9, 10, 4, 5, 3,97//S69812, 1, 10, 15, 9, 2, 6, 8, 0, 13, 3, 4, 14, 7, 5, 11,9910, 15, 4, 2, 7, 12, 9, 5, 6, 1, 13, 14, 0, 11, 3, 8,1009, 14, 15, 5, 2, 8, 12, 3, 7, 0, 4, 10, 1, 13, 11, 6,1014, 3, 2, 12, 9, 5, 15, 10, 11, 14, 1, 7, 6, 0, 8, 13,102//S71034, 11, 2, 14, 15, 0, 8, 13, 3, 12, 9, 7, 5, 10, 6, 1,10413, 0, 11, 7, 4, 9, 1, 10, 14, 3, 5, 12, 2, 15, 8, 6,1051, 4, 11, 13, 12, 3, 7, 14, 10, 15, 6, 8, 0, 5, 9, 2,1066, 11, 13, 8, 1, 4, 10, 7, 9, 5, 0, 15, 14, 2, 3, 12,107//S810813, 2, 8, 4, 6, 15, 11, 1, 10, 9, 3, 14, 5, 0, 12, 7,1091, 15, 13, 8, 10, 3, 7, 4, 12, 5, 6, 11, 0, 14, 9, 2,1107, 11, 4, 1, 9, 12, 14, 2, 0, 6, 10, 13, 15, 3, 5, 8,1112, 1, 14, 7, 4, 10, 8, 13, 15, 12, 9, 0, 3, 5, 6, 11112 };113114void ByteToBit(unsigned char* out, const unsigned char* in, const int bits){115for(int i=0;i<bits;i++)116out[i]=(in[i/8]>>(7-i%8))&1;117 }118119void BitToByte(unsigned char* out, const unsigned char* in, const int bits){120 memset(out, 0, (bits + 7) / 8);121for(int i=0;i<bits;i++)122out[i/8]|=in[i]<<(7-i%8);123 }124125void Transform(unsigned char* out,const unsigned char* in, const unsigned char* table, const int len){ 126 unsigned char tmp[64] = {0};127for (int i = 0; i < len; i++)128 tmp[i] = in[table[i] - 1];129 memcpy(out, tmp, len);130 }131132void RotateL(unsigned char* in, const int len, int loop){133static unsigned char tmp[64];134 memcpy(tmp, in, len);135 memcpy(in, in + loop, len - loop);136 memcpy(in + len - loop, tmp, loop);137 }138139static unsigned char subKey[16][48] = { 0 };140void setKey(const unsigned char* in){141char key[64] = { 0 };142 ByteToBit(key, in, 64);143char temp[56]={0};144 Transform(temp, key, PC1_table, 56);145for(int i=0;i<16;i++){146 RotateL(temp, 28, LOOP_table[i]);147 RotateL(temp + 28, 28, LOOP_table[i]);148 Transform(subKey[i], temp, PC2_table, 48);149 }150 }151152void xor(unsigned char* in1,const unsigned char* in2,int len){153for(int i=0;i<len;i++)154 in1[i]^=in2[i];155 }156157void sbox_exchange(unsigned char* out,const unsigned char* in){158char row, column;159for (int i = 0; i < 8; i++){160char num = 0;161 row = (in[6 * i]<<1)+ in[6 * i + 5];162 column = (in[6 * i + 1] << 3) + (in[6 * i + 2] << 2) + (in[6 * i + 3] << 1) + in[6 * i + 4]; 163 num = sbox[i][row][column];164for (int j = 0; j < 4; j++)165 {166out[4 * i + j] = (num >> (3 - j)) & 1;167 }168 }169 }170171void F_func(unsigned char* out,const unsigned char* in,unsigned char* subKey){172 unsigned char temp[48]={0};173 unsigned char res[32]={0};174 Transform(temp, in, E_table, 48);175 xor(temp,subKey,48);176 sbox_exchange(res,temp);177 Transform(out, res, P_table, 32);178 }179180void encryptDES(unsigned char* out,const unsigned char* in, const unsigned char* key){ 181 unsigned char input[64] = { 0 };182 unsigned char output[64] = { 0 };183 unsigned char tmp[64] = { 0 };184 ByteToBit(input, in, 64);185 Transform(tmp, input, IP_table, 64);186char* Li = &tmp[0], *Ri = &tmp[32];187 setKey(key);188for(int i=0;i<16;i++){189char temp[32]={0};190 memcpy(temp,Ri,32);191 F_func(Ri, Ri,subKey[i]);192 xor(Ri, Li, 32);193 memcpy(Li,temp,32);194 }195 RotateL(tmp, 64, 32);//the input is LR,output is RL196 Transform(output, tmp, IPR_table, 64);197 BitToByte(out, output,64);198 }199200void decryptDES(unsigned char* out,const unsigned char* in, const unsigned char* key){ 201 unsigned char input[64] = { 0 };202 unsigned char output[64] = { 0 };203 unsigned char tmp[64] = { 0 };204 ByteToBit(input, in, 64);205 Transform(tmp, input, IP_table, 64);206char* Li = &tmp[0], *Ri = &tmp[32];207 setKey(key);208 RotateL(tmp, 64, 32);209for (int i = 0; i < 16; i++){210char temp[32] = { 0 };211 memcpy(temp, Li, 32);212 F_func(Li, Li,subKey[15 - i]);213 xor(Li, Ri, 32);214 memcpy(Ri, temp, 32);215 }216 Transform(output, tmp, IPR_table, 64);217 BitToByte(out, output, 64);218 }。

DES加解密算法C语言源代码

DES加解密算法C语言源代码以下是一个实现DES加解密算法的C语言源代码，包含了加密和解密函数。

请注意，这个代码只是为了演示DES算法的工作原理，并不是一个完整的、安全的加密算法实现。

```c#include <stdio.h>#include <stdint.h>typedef structuint8_t key[8];uint8_t subkeys[16][6];} DESKey;void generateSubkeys(uint8_t* key, uint8_t subkeys[16][6]) //略过子密钥生成算法的具体实现//这里只是假设生成的子密钥都是随机的，实际生成过程要更复杂for (int i = 0; i < 16; i++)for (int j = 0; j < 6; j++)subkeys[i][j] = (i+j) % 256;}}void DES(uint8_t* input, uint8_t key[8], uint8_t* output, int encrypt)//略过DES加密算法的具体实现DESKey desKey;for (int i = 0; i < 8; i++)desKey.key[i] = key[i];}generateSubkeys(key, desKey.subkeys);//这里只是假设输入输出是8字节长，实际上可以支持任意长度//执行加解密操作if (encrypt)printf("Encrypting: ");} elseprintf("Decrypting: ");}for (int i = 0; i < 8; i++)output[i] = encrypt ? input[i] ^ desKey.subkeys[0][i%6] : input[i] ^ desKey.subkeys[15][i%6];printf("%02X ", output[i]);}printf("\n");int maiuint8_t input[8] = {0x12, 0x34, 0x56, 0x78, 0x9A, 0xBC, 0xDE, 0xF0};uint8_t key[8] = {0xA1, 0xB2, 0xC3, 0xD4, 0xE5, 0xF6, 0x07,0x08};uint8_t output[8];DES(input, key, output, 1);DES(output, key, output, 0);return 0;```在这个代码中，`generateSubkeys` 函数用于生成 16 个子密钥，之后分别在加密和解密函数 `DES` 中使用。

des密码算法实验c语言

des密码算法实验c语言以下是一个使用C语言实现DES密码算法的简单实验示例：```c#include <stdio.h>#include <stdlib.h>#include <string.h>#include <openssl/des.h>int main() {// 输入明文char plaintext[8] = "12345678";// 初始化DES密钥DES_cblock key = {0x01, 0x23, 0x45, 0x67, 0x89, 0xAB, 0xCD, 0xEF};DES_key_schedule keysched;DES_set_key_unchecked(&key, &keysched);// 加密unsigned char ciphertext[8];DES_cblock ivec = {0}; // 初始化向量DES_ncbc_encrypt(plaintext, ciphertext, sizeof(plaintext),&keysched, &ivec, DES_ENCRYPT);// 输出密文printf("Ciphertext: ");for (int i = 0; i < sizeof(plaintext); i++) {printf("%02X", ciphertext[i]);}printf("\n");// 解密unsigned char decryptedtext[8];memset(ivec, 0, sizeof(ivec)); // 重置初始化向量DES_ncbc_encrypt(ciphertext, decryptedtext, sizeof(plaintext), &keysched, &ivec, DES_DECRYPT);// 输出明文printf("Plaintext: ");for (int i = 0; i < sizeof(plaintext); i++) {printf("%c", decryptedtext[i]);}printf("\n");return 0;}```在这个实验中，我们使用了OpenSSL库中的DES函数来实现DES 密码算法。

DES算法实现

DES算法实现：java语言下可以导入org.apache前缀的类库，apache组织给出了org.apache.codec类库，将基本的加密和解密方法打包成现成方法，并且提供了DES算法必备的S盒。

所以这个实现方法会采用org.apache.codec类库，采用结合源代码的方式进行编写。

工程名为ZDESAl即DES Algorithm,下面包含两个类，DESCoder负责生成密钥，DESCoderTest负责进行密钥的左移、置换选择，扩充等操作。

下面给出DESCoder类的设计思路和源代码：import java.security.Key;import javax.crypto.Cipher;import javax.crypto.KeyGenerator;import javax.crypto.SecretKey;import javax.crypto.SecretKeyFactory;import javax.crypto.spec.DESKeySpec;/***DES安全编码组件*@author Hawke7*@version 1.0*/public abstract class DESCoder {/***密钥算法 *Java6只支持56位密钥 *Bouncy Castle支持64位密钥*/public static final String KEY_ALGORITHM = "DES";/***加密/解密算法/工作模式/填充方式*/public static final String CIPHER_ALGORITHM= "DES/ECB/PKCS5Padding";/***转换密钥*@param key二进制密钥*@return key二进制密钥*@throws Exception*/private static Key toKey(byte[] key) throws Exception {// 实例化DES密钥材料DESKeySpec dks = new DESKeySpec(key);// 实例化秘密密钥工厂SecretKeyFactory keyFactory =SecretKeyFactory.getInstance(KEY_ALGORITHM);// 生成私密密钥SecretKey secretKey = keyFactory.generateSecret(dks);return secretKey;}/***解密*@param data待解密数据*@param key密钥*@return byte[]解密数据*@throws Exception*/public static byte[] decrypt(byte[] data, byte[] key) throws Exception {// 还原密钥Key k = toKey(key);// 实例化Cipher cipher = Cipher.getInstance(CIPHER_ALGORITHM);// 初始化，设置为解密模式cipher.init(Cipher.DECRYPT_MODE, k);// 执行操作return cipher.doFinal(data);}/***加密*@param data待加密数据*@param key密钥*@return byte[]加密数据*@throws Exception*/public static byte[] encrypt(byte[] data, byte[] key) throws Exception {// 还原密钥Key k = toKey(key);// 实例化Cipher cipher = Cipher.getInstance(CIPHER_ALGORITHM);// 初始化，设置为解密模式cipher.init(Cipher.ENCRYPT_MODE, k);// 执行操作return cipher.doFinal(data);}/***生成密钥 *Java6只支持56位密钥 *Bouncy Castle支持64位密钥 *@return byte[]二进制密钥*@throws Exception*/public static byte[] initKey() throws Exception {/** 实例化密钥生成器* 若要使用64位密钥注意替换* 将下述代码中的* KeyGenerator.getInstance(CIPHER_ALGORITHM);* 替换为* KeyGenerator.getInstance(CIPHER_ALGORITHM, "BC");*/KeyGenerator kg = KeyGenerator.getInstance(KEY_ALGORITHM);/** 初始化密钥生成器* 若要使用64位密钥注意替换* 将下面代码kg.init(56)* 替换为kg.init(64)*/kg.init(56);// 生成私密密钥SecretKey secretKey = kg.generateKey();// 获得密钥的二进制编码形式return secretKey.getEncoded();}}首先DESCoder要定义成抽象类，因为其中全部是static静态方法toKey,toKey初始化密钥材料，并且实例化密钥工厂，因为DES算法要进行16轮迭代，所以工厂每一次都要给出不同的密钥，从而增强雪崩效应。

DES加密算法与解密(带流程图)

一、DES加密及解密算法程序源代码：#include <iostream>using namespace std;const static char IP_Table[] = { //IP_Table置换58, 50, 42, 34, 26, 18, 10, 2,60, 52, 44, 36, 28, 20, 12, 4,62, 54, 46, 38, 30, 22, 14, 6,64, 56, 48, 40, 32, 24, 16, 8,57, 49, 41, 33, 25, 17, 9, 1,59, 51, 43, 35, 27, 19, 11, 3,61, 53, 45, 37, 29, 21, 13, 5,63, 55, 47, 39, 31, 23, 15, 7};const static char Final_Table[] = { //最终置换40, 8, 48, 16, 56, 24, 64, 32,39, 7, 47, 15, 55, 23, 63, 31,38, 6, 46, 14, 54, 22, 62, 30,37, 5, 45, 13, 53, 21, 61, 29,36, 4, 44, 12, 52, 20, 60, 28,35, 3, 43, 11, 51, 19, 59, 27,34, 2, 42, 10, 50, 18, 58, 26,33, 1, 41, 9, 49, 17, 57, 25};const static char S_Box[8][64] = { //s_box/* S1 */{14, 4, 13, 1, 2, 15, 11, 8, 3, 10, 6, 12, 5, 9, 0, 7,0, 15, 7, 4, 14, 2, 13, 1, 10, 6, 12, 11, 9, 5, 3, 8,4, 1, 14, 8, 13, 6, 2, 11, 15, 12, 9, 7, 3, 10, 5, 0,15, 12, 8, 2, 4, 9, 1, 7, 5, 11, 3, 14, 10, 0, 6, 13},/* S2 */{15, 1, 8, 14, 6, 11, 3, 4, 9, 7, 2, 13, 12, 0, 5, 10,3, 13, 4, 7, 15, 2, 8, 14, 12, 0, 1, 10, 6, 9, 11, 5,0, 14, 7, 11, 10, 4, 13, 1, 5, 8, 12, 6, 9, 3, 2, 15,13, 8, 10, 1, 3, 15, 4, 2, 11, 6, 7, 12, 0, 5, 14, 9},/* S3 */{10, 0, 9, 14, 6, 3, 15, 5, 1, 13, 12, 7, 11, 4, 2, 8,13, 7, 0, 9, 3, 4, 6, 10, 2, 8, 5, 14, 12, 11, 15, 1,13, 6, 4, 9, 8, 15, 3, 0, 11, 1, 2, 12, 5, 10, 14, 7,1, 10, 13, 0, 6, 9, 8, 7, 4, 15, 14, 3, 11, 5, 2, 12},/* S4 */{7, 13, 14, 3, 0, 6, 9, 10, 1, 2, 8, 5, 11, 12, 4, 15,13, 8, 11, 5, 6, 15, 0, 3, 4, 7, 2, 12, 1, 10, 14, 9,10, 6, 9, 0, 12, 11, 7, 13, 15, 1, 3, 14, 5, 2, 8, 4,3, 15, 0, 6, 10, 1, 13, 8, 9, 4, 5, 11, 12, 7, 2, 14},/* S5 */{2, 12, 4, 1, 7, 10, 11, 6, 8, 5, 3, 15, 13, 0, 14, 9,14, 11, 2, 12, 4, 7, 13, 1, 5, 0, 15, 10, 3, 9, 8, 6,4, 2, 1, 11, 10, 13, 7, 8, 15, 9, 12, 5, 6, 3, 0, 14,11, 8, 12, 7, 1, 14, 2, 13, 6, 15, 0, 9, 10, 4, 5, 3},/* S6 */{12, 1, 10, 15, 9, 2, 6, 8, 0, 13, 3, 4, 14, 7, 5, 11,10, 15, 4, 2, 7, 12, 9, 5, 6, 1, 13, 14, 0, 11, 3, 8,9, 14, 15, 5, 2, 8, 12, 3, 7, 0, 4, 10, 1, 13, 11, 6,4, 3, 2, 12, 9, 5, 15, 10, 11, 14, 1, 7, 6, 0, 8, 13},/* S7 */{4, 11, 2, 14, 15, 0, 8, 13, 3, 12, 9, 7, 5, 10, 6, 1,13, 0, 11, 7, 4, 9, 1, 10, 14, 3, 5, 12, 2, 15, 8, 6,1, 4, 11, 13, 12, 3, 7, 14, 10, 15, 6, 8, 0, 5, 9, 2,6, 11, 13, 8, 1, 4, 10, 7, 9, 5, 0, 15, 14, 2, 3, 12},/* S8 */{13, 2, 8, 4, 6, 15, 11, 1, 10, 9, 3, 14, 5, 0, 12, 7,1, 15, 13, 8, 10, 3, 7, 4, 12, 5, 6, 11, 0, 14, 9, 2,7, 11, 4, 1, 9, 12, 14, 2, 0, 6, 10, 13, 15, 3, 5, 8,2, 1, 14, 7, 4, 10, 8, 13, 15, 12, 9, 0, 3, 5, 6, 11} };const static char Rar_Table[] = { //压缩置换14, 17, 11, 24, 1, 5,3, 28, 15, 6, 21, 10,23, 19, 12, 4, 26, 8,16, 7, 27, 20, 13, 2,41, 52, 31, 37, 47, 55,30, 40, 51, 45, 33, 48,44, 49, 39, 56, 34, 53,46, 42, 50, 36, 29, 32};const static char Exp_Table[] = { //扩展置换32, 1, 2, 3, 4, 5,4, 5, 6, 7, 8, 9,8, 9, 10, 11, 12, 13,12, 13, 14, 15, 16, 17,16, 17, 18, 19, 20, 21,20, 21, 22, 23, 24, 25,24, 25, 26, 27, 28, 29,28, 29, 30, 31, 32, 1};const static char P_Table[]={ //P置换16, 7, 20, 21,29, 12, 28, 17,1, 15, 23, 26,5, 18, 31, 10,2, 8, 24, 14,32, 27, 3, 9,19, 13, 30, 6,22, 11, 4, 25};const static char KeyRar_Table[]={57, 49, 41, 33, 25, 17, 9,1, 58, 50, 42, 34, 26, 18,10, 2, 59, 51, 43, 35, 27,19, 11, 3, 60, 52, 44, 36,63, 55, 47, 39, 31, 23, 15,7, 62, 54, 46, 38, 30, 22,14, 6, 61, 53, 45, 37, 29,21, 13, 5, 28, 20, 12, 4};//设置全局变量，16轮密钥bool key[16][48]={{0}};void ByteToBit(bool *Out,char *In,int bits) //字节到位转换函数{int i;for(i=0;i<bits;i++)Out[i]=(In[i/8]>>(i%8))&1;}void BitToByte(char *Out,bool *In,int bits) //位到字节转换函数{int i;for(i=0;i<bits/8;i++)Out[i]=0;for(i=0;i<bits;i++)Out[i/8]|=In[i]<<(i%8);}void Xor(bool *InA,const bool *InB,int length) //按位异或{for(int i=0;i<length;i++)InA[i]^=InB[i];}void keyfc(char *In) //密钥生成函数{int i,j=0,mov,k,m;bool* key0 = new bool[56];bool* keyin = new bool[64];bool temp;ByteToBit(keyin,In,64); //字节到位的转换for(i=0;i<56;i++) //密钥压缩为56位key0[i]=keyin[KeyRar_Table[i]-1];for(i=0;i<16;i++) //16轮密钥产生{if(i==0||i==1||i==8||i==15)mov=1;elsemov=2;for(k=0;k<mov;k++) //分左右两块循环左移{for(m=0;m<8;m++){temp=key0[m*7];for(j=m*7;j<m*7+7;j++)key0[j]=key0[j+1];key0[m*7+6]=temp;}temp=key0[0];for(m=0;m<27;m++)key0[m]=key0[m+1];key0[27]=temp;temp=key0[28];for(m=28;m<55;m++)key0[m]=key0[m+1];key0[55]=temp;}for(j=0;j<48;j++) //压缩置换并储存key[i][j]=key0[Rar_Table[j]-1];}delete[] key0;delete[] keyin;}void DES(char Out[8],char In[8],bool Type)//加密核心程序,Type=0时加密，反之解密{bool* MW = new bool[64];bool* tmp = new bool[32];bool* PMW = new bool[64];bool* kzmw = new bool[48];bool* keytem = new bool[48];bool* ss = new bool[32];int hang,lie,i;ByteToBit(PMW,In,64);for(int j=0;j<64;j++){MW[j]=PMW[IP_Table[j]-1]; //初始置换}bool *Li=&MW[0],*Ri=&MW[32];for(i=0;i<48;i++) //右明文扩展置换kzmw[i]=Ri[Exp_Table[i]-1];if(Type==0) //DES加密过程{for(int lun=0;lun<16;lun++){for(i=0;i<32;i++)ss[i]=Ri[i];for(i=0;i<48;i++) //右明文扩展置换kzmw[i]=Ri[Exp_Table[i]-1];for(i=0;i<48;i++)keytem[i]=key[lun][i];Xor(kzmw,keytem,48);/*S盒置换*/for(i=0;i<8;i++){hang=kzmw[i*6]*2+kzmw[i*6+5];lie =kzmw[i*6+1]*8+kzmw[i*6+2]*4+kzmw[i*6+3]*2+kzmw[i*6+4];tmp[i*4+3]=S_Box[i][(hang+1)*16+lie]%2;tmp[i*4+2]=(S_Box[i][(hang+1)*16+lie]/2)%2;tmp[i*4+1]=(S_Box[i][(hang+1)*16+lie]/4)%2;tmp[i*4]=(S_Box[i][(hang+1)*16+lie]/8)%2;}for(i=0;i<32;i++) //P置换Ri[i]=tmp[P_Table[i]-1];Xor(Ri,Li,32); //异或for(i=0;i<32;i++) //交换左右明文{Li[i]=ss[i];}}for(i=0;i<32;i++){tmp[i]=Li[i];Li[i]=Ri[i];Ri[i]=tmp[i];}for(i=0;i<64;i++)PMW[i]=MW[Final_Table[i]-1];BitToByte(Out,PMW,64); //位到字节的转换}else //DES解密过程{for(int lun=15;lun>=0;lun--){for(i=0;i<32;i++)ss[i]=Ri[i];for(i=0;i<48;i++) //右明文扩展置换kzmw[i]=Ri[Exp_Table[i]-1];for(i=0;i<48;i++)keytem[i]=key[lun][i];Xor(kzmw,keytem,48);/*S盒置换*/for(i=0;i<8;i++){hang=kzmw[i*6]*2+kzmw[i*6+5];lie =kzmw[i*6+1]*8+kzmw[i*6+2]*4+kzmw[i*6+3]*2+kzmw[i*6+4];tmp[i*4+3]=S_Box[i][(hang+1)*16+lie]%2;tmp[i*4+2]=(S_Box[i][(hang+1)*16+lie]/2)%2;tmp[i*4+1]=(S_Box[i][(hang+1)*16+lie]/4)%2;tmp[i*4]=(S_Box[i][(hang+1)*16+lie]/8)%2;}for(i=0;i<32;i++) //P置换Ri[i]=tmp[P_Table[i]-1];Xor(Ri,Li,32); //异或for(i=0;i<32;i++) //交换左右明文{Li[i]=ss[i];}}for(i=0;i<32;i++){tmp[i]=Li[i];Li[i]=Ri[i];Ri[i]=tmp[i];}for(i=0;i<64;i++)PMW[i]=MW[Final_Table[i]-1];BitToByte(Out,PMW,64); //位到字节的转换}delete[] MW;delete[] tmp;delete[] PMW;delete[] kzmw;delete[] keytem;delete[] ss;}bool RunDes(char *Out, char *In, int datalength, char *Key, bool Type) //加密运行函数，判断输入以及对输入文本8字节分割{if( !( Out && In && Key && (datalength=(datalength+7)&0xfffffff8) ) )return false;keyfc(Key);for(int i=0,j=datalength%8; i<j; ++i,Out+=8,In+=8)DES(Out, In, Type);return true;}int main(){char* Ki = new char[8];char Enter[]="This is the test of DES!";char* Print = new char[200];int len = sizeof(Enter);int i_mf;cout << "请输入密钥（8位）：" <<"\n";for(i_mf=0;i_mf<8;i_mf++)cin >> Ki[i_mf];cout << "\n";RunDes(Print,Enter,len,Ki,0);//加密cout << "----加密前----" << "\n";for(i_mf=0;i_mf<len;i_mf++)cout << Enter[i_mf];cout << "\n\n";cout << "----加密后----" << "\n";for(i_mf=0;i_mf<len;i_mf++)cout<<Print[i_mf];cout << "\n\n";//此处进行不同密钥输入测试cout << "请输入密钥（8位）：" <<"\n";for(i_mf=0;i_mf<8;i_mf++)cin >> Ki[i_mf];cout << "\n";RunDes(Enter,Print,len,Ki,1);//解密cout << "----解密后----" << "\n";for(i_mf=0;i_mf<len;i_mf++)cout << Enter[i_mf];cout << endl;delete[] Ki;delete[] Print;return 0;}二、程序编译、运行结果图：三、程序总体框架图：读取待加密文本输入密钥DES 加密显示加密后文本再次输入密钥DES 解密显示解密后文本显示错误解密信息密钥错误密钥正确四、程序实现流程图：。

des加密算法c语言源代码

#include<iostream.h>int IP[64] = {58,50,42,34,26,18,10,2,60,52,44,36,28,20,12,4,62,54,46,38,30,22,14,6,64,56,48,40,32,24,16,8,57,49,41,33,25,17,9,1,59,51,43,35,27,19,11,3,61,53,45,37,29,21,13,5,63,55,47,39,31,23,15,7};int IP_1[64] = {40,8,48,16,56,24,64,32,39,7,47,15,55,23,63,31,38,6,46,14,54,22,62,30,37,5,45,13,53,21,61,29,36,4,44,12,52,20,60,28,35,3,43,11,51,19,59,27,34,2,42,10,50,18,58,26,33,1,41,9,49,17,57,25};int E[48] = {32,1, 2, 3, 4, 5,4, 5, 6, 7, 8, 9,8, 9, 10,11,12,13,12,13,14,15,16,17,16,17,18,19,20,21,20,21,22,23,24,25,24,25,26,27,28,29,28,29,30,31,32,1};int P[32]={16 ,7 , 20 , 21 ,29,12 ,28 , 17 ,1, 15 ,23 , 26 ,5, 18 ,31 , 10 ,2, 8 , 24 , 14 ,32,27, 3 , 9 ,19,13, 30 , 6 ,22,11 ,4 , 25 };void Char_to_Int(unsigned char in[],int out[],int len){for(int i=0;i<len;i++)out[i]=int(in[i]);}void Int_to_Char(int in[],unsigned char out[],int len){for(int i=0;i<len;i++)out[i]=char(in[i]);}void B_to_H(int in[],unsigned char out[]){for(int i=0;i<16;i++){int temp=in[i*4]*8+in[i*4+1]*4+in[i*4+2]*2+in[i*4+3];switch(temp){case 10 :out[i]='A';break;case 11 :out[i]='B';break;case 12 :out[i]='C';break;case 13 :out[i]='D';break;case 14 :out[i]='E';break;case 15 :out[i]='F';break;default :out[i]=unsigned char(temp+48);break;}}}void H_to_B(unsigned char in[],int out[]){for(int i=0;i<16;i++)switch(in[i]){case 'A':out[i*4]=1;out[i*4+1]=0;out[i*4+2]=1;out[i*4+3]=0;break;case 'B':out[i*4]=1;out[i*4+1]=0;out[i*4+2]=1;out[i*4+3]=1;break;case 'C':out[i*4]=1;out[i*4+1]=1;out[i*4+2]=0;out[i*4+3]=0;break;case 'D':out[i*4]=1;out[i*4+1]=1;out[i*4+2]=0;out[i*4+3]=1;break;case 'E':out[i*4]=1;out[i*4+1]=1;out[i*4+2]=1;out[i*4+3]=0;break;case 'F':out[i*4]=1;out[i*4+1]=1;out[i*4+2]=1;out[i*4+3]=1;break;case '0':out[i*4]=0;out[i*4+1]=0;out[i*4+2]=0;out[i*4+3]=0;break;case '1':out[i*4]=0;out[i*4+1]=0;out[i*4+2]=0;out[i*4+3]=1;break;case '2':out[i*4]=0;out[i*4+1]=0;out[i*4+2]=1;out[i*4+3]=0;break;case '3':out[i*4]=0;out[i*4+1]=0;out[i*4+2]=1;out[i*4+3]=1;break;case '4':out[i*4]=0;out[i*4+1]=1;out[i*4+2]=0;out[i*4+3]=0;break;case '5':out[i*4]=0;out[i*4+1]=1;out[i*4+2]=0;out[i*4+3]=1;break;case '6':out[i*4]=0;out[i*4+1]=1;out[i*4+2]=1;out[i*4+3]=0;break;case '7':out[i*4]=0;out[i*4+1]=1;out[i*4+2]=1;out[i*4+3]=1;break;case '8':out[i*4]=1;out[i*4+1]=0;out[i*4+2]=0;out[i*4+3]=0;break;case '9':out[i*4]=1;out[i*4+1]=0;out[i*4+2]=0;out[i*4+3]=1;break;}}void O_to_B(int in[],int out[],int len){int i,j;for(i=0;i<len;i++)for(j=i*len+7;j>=i*len;j--){out[j]=in[i]%2; in[i]=in[i]/2;}}void B_to_O(int in[],int out[],int len){int j;for(int i=0;i<len;i++){j=8*i;out[i]=in[j]*128+in[j+1]*64+in[j+2]*32+in[j+3]*16+in[j+4]*8+in[j+5]*4+in[j+6]*2+in[j+7]*1;}}void Convert(int in[],int out[],int table[],int len){for(int i=0;i<len;i++)out[i]=in[table[i]-1];}void Divide(int in[],int out1[],int out2[],int len){for(int i=0;i<len;i++)if(i<len/2)out1[i]=in[i];elseout2[i-len/2]=in[i];}//正确void Combine(int in1[],int in2[],int out[],int len){for(int i=0;i<len;i++)if(i<len/2)out[i]=in1[i];elseout[i]=in2[i-len/2];}//正确void RLC1(int in[],int out[],int len){int temp=in[0];for(int i=0;i<len-1;i++)out[i]=in[i+1];out[len-1]=temp;}//正确void RLC2(int in[],int out[],int len){int temp1=in[0],temp2=in[1];for(int i=0;i<len-2;i++)out[i]=in[i+2];out[len-2]=temp1;out[len-1]=temp2;}//正确void COPY(int in[],int out[],int len){for(int i=0;i<len;i++)out[i]=in[i];}//ZHENGQUEvoid XOR(int in1[],int in2[],int out[],int len){for(int i=0;i<len;i++)out[i]=(in1[i]+in2[i])%2;}void GetKey(unsigned char in[],int out[16][48]){int i;int Msg_Int[8],Msg_Bin[64],Msg_Bin_PC1[56],Key_Bin[56],C[17][28],D[17][28];char Msg_H[16];int PC1[56]={57,49,41,33,25,17,9,1,58,50,42,34,26,18,10,2,59,51,43,35,27,19,11,3,60,52,44,36,63,55,47,39,31,23,15,7,62,54,46,38,30,22,14,6,61,53,45,37,29,21,13,5,28,20,12,4},PC2[48]={14,17,11,24,1,5,3,28,15,6,21,10,23,19,12,4,26,8,16,7,27,20,13,2,41,52,31,37,47,55,30,40,51,45,33,48,44,49,39,56,34,53,46,42,50,36,29,32};Char_to_Int(in,Msg_Int,8);//正确O_to_B(Msg_Int,Msg_Bin,8);//正确cout<<endl;Convert(Msg_Bin,Msg_Bin_PC1,PC1,56); Divide(Msg_Bin_PC1,C[0],D[0],56);for(i=0;i<16;i++){if(i==0){RLC1(C[i],C[i+1],28);RLC1(D[i],D[i+1],28);}else if(i==1){RLC1(C[i],C[i+1],28);RLC1(D[i],D[i+1],28);}else if(i==8){RLC1(C[i],C[i+1],28);RLC1(D[i],D[i+1],28);}else if(i==15){RLC1(C[i],C[i+1],28);RLC1(D[i],D[i+1],28);}else{RLC2(C[i],C[i+1],28);RLC2(D[i],D[i+1],28);}Combine(C[i+1],D[i+1],Key_Bin,56);Convert(Key_Bin,out[i],PC2,48);}} //生成子密钥正确void S_box(int in[],int out[]){int i;int SBox[8][64] ={{14,4,13,1,2,15,11,8,3,10,6,12,5,9,0,7,0,15,7,4,14,2,13,1,10,6,12,11,9,5,3,8,4,1,14,8,13,6,2,11,15,12,9,7,3,10,5,0,15,12,8,2,4,9,1,7,5,11,3,14,10,0,6,13},{15,1,8,14,6,11,3,4,9,7,2,13,12,0,5,10,3,13,4,7,15,2,8,14,12,0,1,10,6,9,11,5,0,14,7,11,10,4,13,1,5,8,12,6,9,3,2,15,13,8,10,1,3,15,4,2,11,6,7,12,0,5,14,9},{10,0,9,14,6,3,15,5,1,13,12,7,11,4,2,8,13,7,0,9,3,4,6,10,2,8,5,14,12,11,15,1,13,6,4,9,8,15,3,0,11,1,2,12,5,10,14,7,1,10,13,0,6,9,8,7,4,15,14,3,11,5,2,12},{7,13,14,3,0,6,9,10,1,2,8,5,11,12,4,15,13,8,11,5,6,15,0,3,4,7,2,12,1,10,14,9,10,6,9,0,12,11,7,13,15,1,3,14,5,2,8,4,3,15,0,6,10,1,13,8,9,4,5,11,12,7,2,14},{2,12,4,1,7,10,11,6,8,5,3,15,13,0,14,9,14,11,2,12,4,7,13,1,5,0,15,10,3,9,8,6,4,2,1,11,10,13,7,8,15,9,12,5,6,3,0,14,11,8,12,7,1,14,2,13,6,15,0,9,10,4,5,3,},{12,1,10,15,9,2,6,8,0,13,3,4,14,7,5,11,10,15,4,2,7,12,9,5,6,1,13,14,0,11,3,8,9,14,15,5,2,8,12,3,7,0,4,10,1,13,11,6,4,3,2,12,9,5,15,10,11,14,1,7,6,0,8,13},{4,11,2,14,15,0,8,13,3,12,9,7,5,10,6,1,13,0,11,7,4,9,1,10,14,3,5,12,2,15,8,6,1,4,11,13,12,3,7,14,10,15,6,8,0,5,9,2,6,11,13,8,1,4,10,7,9,5,0,15,14,2,3,12},{13,2,8,4,6,15,11,1,10,9,3,14,5,0,12,7,1,15,13,8,10,3,7,4,12,5,6,11,0,14,9,2,7,11,4,1,9,12,14,2,0,6,10,13,15,3,5,8,2,1,14,7,4,10,8,13,15,12,9,0,3,5,6,11}};int s1,s3,s2[8];for(i=0;i<8;i++){s1=in[i*6]*2+in[i*6+5]*1;s3=in[i*6+1]*8+in[i*6+2]*4+in[i*6+3]*2+in[i*6+4]*1;s2[i]=SBox[i][s1*16+s3];}int j;for(i=0;i<8;i++)for(j=i*4+3;j>=i*4;j--){out[j]=s2[i]%2; s2[i]=s2[i]/2;}}void Encode(unsigned char in[],unsigned char Final_H[],int K[16][48]){int i;intORINT[8],ORBYTE[64],FinalBYTE[64],LR[64],R48[48],S_in[48],S_out[32],F_RL[32],FinalINT[8],L[17] [32],R[17][32];char ORH[16];Char_to_Int(in,ORINT,8);cout<<""<<endl;O_to_B(ORINT,ORBYTE,8);Convert(ORBYTE,LR,IP,64);Divide(LR,L[0],R[0],64);for(i=1;i<17;i++){Convert(R[i-1],R48,E,48);XOR(R48,K[i-1],S_in,48);S_box(S_in,S_out);Convert(S_out,F_RL,P,32);XOR(F_RL,L[i-1],R[i],32);COPY(R[i-1],L[i],32);}Combine(R[16],L[16],LR,64);Convert(LR,FinalBYTE,IP_1,64);cout<<"二进制的密文:"<<endl;for(i=0;i<64;i++){cout<<FinalBYTE[i];}cout<<endl<<endl;B_to_H(FinalBYTE,Final_H);}void DeCode(unsigned char in[],unsigned char Final_H[],int K[16][48]){int i;intORINT[8],ORBYTE[64],LR[64],R48[48],S_in[48],S_out[32],F_RL[32],FinalBYTE[64],FinalINT[8],L[17] [32],R[17][32];char ORH[16];Char_to_Int(in,ORINT,8);cout<<""<<endl;O_to_B(ORINT,ORBYTE,8);Convert(ORBYTE,LR,IP,64);Divide(LR,L[0],R[0],64);for(i=1;i<17;i++){COPY(R[i-1],L[i],32);Convert(R[i-1],R48,E,48);XOR(R48,K[16-i],S_in,48);S_box(S_in,S_out);Convert(S_out,F_RL,P,32);XOR(L[i-1],F_RL,R[i],32);}Combine(R[16],L[16],LR,64);Convert(LR,FinalBYTE,IP_1,64);B_to_H(FinalBYTE,Final_H);}void main(){int i;unsigned char Msg[8],UnCodeMsg[16],CodeMsg[16],Key[8],Msg_H[16],CodeChar[8];int SKey[16][48];int OrByte[64],OrInt[8],FinalByte[64],FinalInt[8];cout<<"请输入明文："<<endl;for(i=0;i<8;i++)cin>>Msg[i];cout<<"请输入初始密钥："<<endl;for(i=0;i<8;i++)cin>>Key[i];GetKey(Key,SKey);Encode(Msg,CodeMsg,SKey);cout<<"十六进制的密文："<<endl;for(i=0;i<16;i++)cout<<CodeMsg[i];cout<<endl;cout<<"字符型密文："<<endl;H_to_B(CodeMsg,FinalByte);B_to_O(FinalByte,FinalInt,8);Int_to_Char(FinalInt,CodeChar,8);for(i=0;i<8;i++)cout<<CodeChar[i];cout<<endl;cout<<"请输入十六进制的密文："<<endl;for(i=0;i<16;i++)cin>>CodeMsg[i];B_to_O(FinalByte,FinalInt,8);Int_to_Char(FinalInt,CodeChar,8);cout<<"请输入解密密钥："<<endl;for(i=0;i<8;i++)cin>>Key[i];GetKey(Key,SKey);DeCode(CodeChar,Msg_H,SKey);//for(i=0;i<16;i++)// cout<<Msg_H[i];cout<<endl;H_to_B(Msg_H,OrByte);B_to_O(OrByte,OrInt,8);Int_to_Char(OrInt,Msg,8);cout<<"明文是："<<endl;for(i=0;i<8;i++)cout<<Msg[i];cout<<endl;}。

des密码算法程序c语言

des密码算法程序c语言一、概述DES（数据加密标准）是一种常用的对称加密算法，它采用64位的密钥，对数据进行加密和解密。

本程序使用C语言实现DES算法，包括密钥生成、数据加密和解密等操作。

二、算法实现1.密钥生成：使用初始置换算法IP(56位)将明文转化为56位的分组，再将该分组经过一系列的逻辑函数F进行6轮处理，最终生成一个56位的密文。

其中密钥包括56位数据位和8位奇偶校验位。

2.数据加密：将需要加密的数据转化为56位的分组，再经过DES 算法处理，得到密文。

3.数据解密：将密文经过DES算法处理，还原成原始明文。

三、程序代码```c#include<stdio.h>#include<string.h>#include<stdlib.h>#include<time.h>//DES算法参数定义#defineITERATIONS6//加密轮数#defineKEY_LENGTH8//密钥长度，单位为字节#defineBLOCK_SIZE8//数据分组长度，单位为字节#definePADDINGPKCS7Padding//填充方式#defineMAX_INPUT_LENGTH(BLOCK_SIZE*2)//数据输入的最大长度//初始置换函数voidinit_permutation(unsignedcharinput[BLOCK_SIZE]){inti;for(i=0;i<BLOCK_SIZE;i++){input[i]=i;}}//逻辑函数F的定义voidlogic_function(unsignedcharinput[BLOCK_SIZE],unsigned charoutput[BLOCK_SIZE]){inti;for(i=0;i<BLOCK_SIZE;i++){output[i]=input[(i+1)%BLOCK_SIZE]^input[i]^(i+1)/BLOCK_SI ZE;}}//DES算法主函数voiddes_encrypt(unsignedchar*input,unsignedchar*output){ unsignedcharkey[KEY_LENGTH];//密钥数组unsignedchariv[BLOCK_SIZE];//初始置换的输入数组unsignedcharciphertext[MAX_INPUT_LENGTH];//密文数组unsignedcharpadding[BLOCK_SIZE];//填充数组unsignedintlength=strlen((char*)input);//数据长度（以字节为单位）unsignedintpadding_length=(length+BLOCK_SIZE-1)%BLOCK_SIZE;//需要填充的字节数unsignedintround=0;//加密轮数计数器unsignedintj=0;//数据指针，用于循环读取数据和填充数据intkey_offset=((1<<(32-KEY_LENGTH))-1)<<(32-(ITERATIONS*BLOCK_SIZE));//密钥索引值，用于生成密钥数组和填充数组的初始值unsignedintk=0;//DES算法中每个轮次的密钥索引值，用于生成每个轮次的密钥数组和填充数组的值unsignedintkplus1=(k+1)%((1<<(32-BLOCK_SIZE))-1);//DES算法中每个轮次的密钥索引值加一后的值，用于下一个轮次的密钥生成charseed[32];//使用MD5作为初始种子值生成随机数序列chartmp[MAX_INPUT_LENGTH];//临时变量数组，用于数据交换和中间计算结果存储等操作time_tt;//时间戳变量，用于生成随机数序列的种子值srand((unsignedint)time(&t));//设置随机数种子值，确保每次运行生成的随机数序列不同init_permutation(iv);//初始置换操作，将输入数据转化为56位分组（需要重复填充时）或一个随机的分组（不需要重复填充时）memcpy(key,key_offset,sizeof(key));//将初始化的密钥数组复制到相应的位置上，以便于接下来的轮次生成不同的密钥值memcpy(padding,seed,sizeof(seed));//将种子值复制到填充数组中，以便于接下来的轮次生成不同的随机数序列值for(round=0;round<ITERATIONS;round++){//进行加密轮次操作，每轮包括。

DES算法代码及实验报告

DES算法代码及实验报告DES算法（Data Encryption Standard，数据加密标准）是一种对称密钥加密算法，是密码学中最为经典的算法之一、DES算法的核心是Feistel结构，通过将明文分成多个块，然后对每个块进行一系列的置换和替换操作，最后得到密文。

本文将给出DES算法的代码实现，并进行实验报告。

一、DES算法的代码实现：以下是使用Python语言实现的DES算法代码：```pythondef str_to_bitlist(text):bits = []for char in text:binval = binvalue(char, 8)bits.extend([int(x) for x in list(binval)])return bitsdef bitlist_to_str(bits):chars = []for b in range(len(bits) // 8):byte = bits[b * 8:(b + 1) * 8]chars.append(chr(int(''.join([str(bit) for bit in byte]), 2)))return ''.join(chars)def binvalue(val, bitsize):binary = bin(val)[2:] if isinstance(val, int) elsebin(ord(val))[2:]if len(binary) > bitsize:raise Exception("Binary value larger than the expected size.")while len(binary) < bitsize:binary = "0" + binaryreturn binarydef permute(sbox, text):return [text[pos - 1] for pos in sbox]def generate_round_keys(key):key = str_to_bitlist(key)key = permute(self.permuted_choice_1, key)left, right = key[:28], key[28:]round_keys = []for i in range(16):left, right = shift(left, self.shift_table[i]), shift(right, self.shift_table[i])round_key = left + rightround_key = permute(self.permuted_choice_2, round_key)round_keys.append(round_key)return round_keysdef shift(bits, shift_val):return bits[shift_val:] + bits[:shift_val]def xor(bits1, bits2):return [int(bit1) ^ int(bit2) for bit1, bit2 in zip(bits1, bits2)]def encrypt(text, key):text_bits = str_to_bitlist(text)round_keys = generate_round_keys(key)text_bits = permute(self.initial_permutation, text_bits)left, right = text_bits[:32], text_bits[32:]for i in range(16):expansion = permute(self.expansion_table, right)xor_val = xor(round_keys[i], expansion)substitution = substitute(xor_val)permut = permute(self.permutation_table, substitution)temp = rightright = xor(left, permut)left = tempreturn bitlist_to_str(permute(self.final_permutation, right + left))```二、DES算法的实验报告：1.实验目的通过实现DES算法，加深对DES算法原理的理解，验证算法的正确性和加密效果。

DES加密C语言实现源代码

void *memcpy( void *dest, const void *src, unsigned char count ){// ASSERT((dest != NULL)&&(src != NULL));unsigned char *temp_dest = (unsigned char *)dest;unsigned char *temp_src = (unsigned char *)src;while(count--) // 不对是否存在重叠区域进行判断{*temp_dest++ = *temp_src++;}return dest;}unsigned char *memset(unsigned char *dst,unsigned char value,unsigned char count) {unsigned char *start = dst;while (count--)*dst++ = value;return(start);}// 初始置换表IPunsigned char IP_Table[64] = { 57,49,41,33,25,17,9,1,59,51,43,35,27,19,11,3,61,53,45,37,29,21,13,5,63,55,47,39,31,23,15,7,56,48,40,32,24,16,8,0,58,50,42,34,26,18,10,2,60,52,44,36,28,20,12,4,62,54,46,38,30,22,14,6};//逆初始置换表IP^-1unsigned char IP_1_Table[64] = {39,7,47,15,55,23,63,31,38,6,46,14,54,22,62,30,37,5,45,13,53,21,61,29,36,4,44,12,52,20,60,28,35,3,43,11,51,19,59,27,34,2,42,10,50,18,58,26,33,1,41,9,49,17,57,25,32,0,40,8,48,16,56,24}; //扩充置换表Eunsigned char E_Table[48] = {31, 0, 1, 2, 3, 4,3, 4, 5, 6, 7, 8,7, 8,9,10,11,12,11,12,13,14,15,16,15,16,17,18,19,20,19,20,21,22,23,24,23,24,25,26,27,28,27,28,29,30,31, 0};//置换函数Punsigned char P_Table[32] = {15,6,19,20,28,11,27,16,0,14,22,25,4,17,30,9,1,7,23,13,31,26,2,8,18,12,29,5,21,10,3,24};//S盒unsigned char S[8][4][16] =// S1 {{{14,4,13,1,2,15,11,8,3,10,6,12,5,9,0,7}, {0,15,7,4,14,2,13,1,10,6,12,11,9,5,3,8}, {4,1,14,8,13,6,2,11,15,12,9,7,3,10,5,0}, {15,12,8,2,4,9,1,7,5,11,3,14,10,0,6,13}}, // S2{{15,1,8,14,6,11,3,4,9,7,2,13,12,0,5,10}, {3,13,4,7,15,2,8,14,12,0,1,10,6,9,11,5}, {0,14,7,11,10,4,13,1,5,8,12,6,9,3,2,15}, {13,8,10,1,3,15,4,2,11,6,7,12,0,5,14,9}}, //S3{{10,0,9,14,6,3,15,5,1,13,12,7,11,4,2,8}, {13,7,0,9,3,4,6,10,2,8,5,14,12,11,15,1}, {13,6,4,9,8,15,3,0,11,1,2,12,5,10,14,7}, {1,10,13,0,6,9,8,7,4,15,14,3,11,5,2,12}}, // S4{{7,13,14,3,0,6,9,10,1,2,8,5,11,12,4,15}, {13,8,11,5,6,15,0,3,4,7,2,12,1,10,14,9}, {10,6,9,0,12,11,7,13,15,1,3,14,5,2,8,4}, {3,15,0,6,10,1,13,8,9,4,5,11,12,7,2,14}}, //S5{{2,12,4,1,7,10,11,6,8,5,3,15,13,0,14,9},{14,11,2,12,4,7,13,1,5,0,15,10,3,9,8,6},{4,2,1,11,10,13,7,8,15,9,12,5,6,3,0,14}, {11,8,12,7,1,14,2,13,6,15,0,9,10,4,5,3}},//S6{{12,1,10,15,9,2,6,8,0,13,3,4,14,7,5,11}, {10,15,4,2,7,12,9,5,6,1,13,14,0,11,3,8},{9,14,15,5,2,8,12,3,7,0,4,10,1,13,11,6},{4,3,2,12,9,5,15,10,11,14,1,7,6,0,8,13}},// S7{{4,11,2,14,15,0,8,13,3,12,9,7,5,10,6,1}, {13,0,11,7,4,9,1,10,14,3,5,12,2,15,8,6},{1,4,11,13,12,3,7,14,10,15,6,8,0,5,9,2},{6,11,13,8,1,4,10,7,9,5,0,15,14,2,3,12}},//S8{{13,2,8,4,6,15,11,1,10,9,3,14,5,0,12,7},{1,15,13,8,10,3,7,4,12,5,6,11,0,14,9,2},{7,11,4,1,9,12,14,2,0,6,10,13,15,3,5,8},{2,1,14,7,4,10,8,13,15,12,9,0,3,5,6,11}}};//置换选择1unsigned char PC_1[56] = {56,48,40,32,24,16,8,0,57,49,41,33,25,17,9,1,58,50,42,34,26,18,10,2,59,51,43,35,62,54,46,38,30,22,14,6,61,53,45,37,29,21,13,5,60,52,44,36,28,20,12,4,27,19,11,3};//置换选择2unsigned char PC_2[48] = {13,16,10,23,0,4,2,27,14,5,20,9,22,18,11,3,25,7,15,6,26,19,12,1,40,51,30,36,46,54,29,39,50,44,32,46,43,48,38,55,33,52,45,41,49,35,28,31};// 对左移次数的规定unsigned char MOVE_TIMES[16] = {1,1,2,2,2,2,2,2,1,2,2,2,2,2,2,1}; //字节转换成二进制unsigned char ByteToBit(unsigned char ch, unsigned char bit[8]) {unsigned char cnt;for(cnt = 0;cnt < 8; cnt++){*(bit+cnt) = (ch>>cnt)&1;}return 0;}// 二进制转换成字节unsigned char BitToByte(unsigned char bit[8],unsigned char *ch){unsigned char cnt;for(cnt = 0;cnt < 8; cnt++){*ch |= *(bit + cnt)<<cnt;}return 0;}// 将长度为8的字符串转为二进制位串unsigned char Char8ToBit64(unsigned char ch[8],unsigned char bit[64]){unsigned char cnt;for(cnt = 0; cnt < 8; cnt++){ByteToBit(*(ch+cnt),bit+(cnt<<3));}return 0;}// 将二进制位串转为长度为8的字符串unsigned char Bit64ToChar8(unsigned char bit[64],unsigned char ch[8]){unsigned char cnt;memset(ch,0,8);for(cnt = 0; cnt < 8; cnt++){BitToByte(bit+(cnt<<3),ch+cnt);}return 0;}// 密钥置换1unsigned char DES_PC1_Transform(unsigned char key[64], unsigned char tempbts[56]) {unsigned char cnt;for(cnt = 0; cnt < 56; cnt++){tempbts[cnt] = key[PC_1[cnt]];}return 0;}//密钥置换2unsigned char DES_PC2_Transform(unsigned char key[56], unsigned char tempbts[48]) {unsigned char cnt;for(cnt = 0; cnt < 48; cnt++){tempbts[cnt] = key[PC_2[cnt]];}return 0;}//循环左移unsigned char DES_ROL(unsigned char data[56], unsigned char time){unsigned char temp[56];//保存将要循环移动到右边的位memcpy(temp,data,time);memcpy(temp+time,data+28,time);//前28位移动memcpy(data,data+time,28-time);memcpy(data+28-time,temp,time);//后28位移动memcpy(data+28,data+28+time,28-time);memcpy(data+56-time,temp+time,time);return 0;}//IP置换unsigned char DES_IP_Transform(unsigned char data[64]){unsigned char cnt;unsigned char temp[64];for(cnt = 0; cnt < 64; cnt++){temp[cnt] = data[IP_Table[cnt]];}memcpy(data,temp,64);return 0;}// IP逆置换unsigned char DES_IP_1_Transform(unsigned char data[64]) {unsigned char cnt;unsigned char temp[64];for(cnt = 0; cnt < 64; cnt++){temp[cnt] = data[IP_1_Table[cnt]];}memcpy(data,temp,64);return 0;}//扩展置换unsigned char DES_E_Transform(unsigned char data[48]) {unsigned char cnt;unsigned char temp[48];for(cnt = 0; cnt < 48; cnt++){temp[cnt] = data[E_Table[cnt]];}memcpy(data,temp,48);return 0;}//P置换unsigned char DES_P_Transform(unsigned char data[32]) {unsigned char cnt;unsigned char temp[32];for(cnt = 0; cnt < 32; cnt++){temp[cnt] = data[P_Table[cnt]];}memcpy(data,temp,32);return 0;}// 异或unsigned char DES_XOR(unsigned char R[48], unsigned char L[48] ,unsigned char count) {unsigned char cnt;for(cnt = 0; cnt < count; cnt++){R[cnt] ^= L[cnt];}return 0;}// S盒置换unsigned char DES_SBOX(unsigned char data[48]){unsigned char cnt;unsigned char line,row,output;unsigned char cur1,cur2;for(cnt = 0; cnt < 8; cnt++){cur1 = cnt*6;cur2 = cnt<<2;// 计算在S盒中的行与列line = (data[cur1]<<1) + data[cur1+5];row = (data[cur1+1]<<3) + (data[cur1+2]<<2)+ (data[cur1+3]<<1) + data[cur1+4];output = S[cnt][line][row];// 化为2进制data[cur2] = (output&0X08)>>3;data[cur2+1] = (output&0X04)>>2;data[cur2+2] = (output&0X02)>>1;data[cur2+3] = output&0x01;}return 0;}//交换unsigned char DES_S char left[32], unsigned char right[32]){unsigned char temp[32];memcpy(temp,left,32);memcpy(left,right,32);memcpy(right,temp,32);return 0;}//生成子密钥unsigned char DES_MakeSubKeys(unsigned char key[64],unsigned char subKeys[16][48]){unsigned char temp[56];unsigned char cnt;DES_PC1_Transform(key,temp);// PC1置换for(cnt = 0; cnt < 16; cnt++) //16轮跌代，产生16个子密钥{DES_ROL(temp,MOVE_TIMES[cnt]);// 循环左移DES_PC2_Transform(temp,subKeys[cnt]);//PC2置换，产生子密钥}return 0;}//加密单个分组unsigned char DES_EncryptBlock(unsigned char plainBlock[8], unsigned char subKeys[16][48], unsigned char cipherBlock[8]){unsigned char plainBits[64];unsigned char copyRight[48];unsigned char cnt;Char8ToBit64(plainBlock,plainBits);//初始置换（IP置换）DES_IP_Transform(plainBits);// 16轮迭代for(cnt = 0; cnt < 16; cnt++){memcpy(copyRight,plainBits+32,32);DES_E_Transform(copyRight); // 将右半部分进行扩展置换，从32位扩展到48位DES_XOR(copyRight,subKeys[cnt],48); // 将右半部分与子密钥进行异或操作DES_SBOX(copyRight); // 异或结果进入S盒，输出32位结果DES_P_Transform(copyRight); // P置换DES_XOR(plainBits,copyRight,32); //将明文左半部分与右半部分进行异或if(cnt != 15){DES_S);//最终完成左右部的交换}}DES_IP_1_Transform(plainBits); //逆初始置换（IP^1置换）Bit64ToChar8(plainBits,cipherBlock);return 0;}// 解密单个分组unsigned char DES_DecryptBlock(unsigned char cipherBlock[8], unsigned char subKeys[16][48],unsigned char plainBlock[8]){unsigned char cipherBits[64];unsigned char copyRight[48];short cnt;Char8ToBit64(cipherBlock,cipherBits);//初始置换（IP置换）DES_IP_Transform(cipherBits);// 16轮迭代for(cnt = 15; cnt >= 0; cnt--){memcpy(copyRight,cipherBits+32,32);//将右半部分进行扩展置换，从32位扩展到48位DES_E_Transform(copyRight);// 将右半部分与子密钥进行异或操作DES_XOR(copyRight,subKeys[cnt],48);//异或结果进入S盒，输出32位结果DES_SBOX(copyRight);// P置换DES_P_Transform(copyRight);//将明文左半部分与右半部分进行异或DES_XOR(cipherBits,copyRight,32);if(cnt != 0){// 最终完成左右部的交换DES_S);}}// 逆初始置换（IP^1置换）DES_IP_1_Transform(cipherBits);Bit64ToChar8(cipherBits,plainBlock);return 0;}//加密文件unsigned char DES_Encrypt(unsigned char *keyStr,unsigned char *plain char *cipherFile){unsigned char keyBlock[8],bKey[64],subKeys[16][48];memcpy(keyBlock,keyStr,8); //设置密钥Char8ToBit64(keyBlock,bKey); //将密钥转换为二进制流DES_MakeSubKeys(bKey,subKeys); //生成子密钥DES_EncryptBlock(plain);return 1;}//解密文件unsigned char DES_Decrypt(unsigned char *keyStr,unsigned char *cipher char *plainFile){// unsigned char plainBlock[8],cipherBlock[8],unsigned char bKey[64],keyBlock[8],subKeys[16][48];memcpy(keyBlock,keyStr,8); //设置密钥Char8ToBit64(keyBlock,bKey); //将密钥转换为二进制流DES_MakeSubKeys(bKey,subKeys); //生成子密钥DES_DecryptBlock(cipher);return 1;}/****************************************************************************** ****************** 作者：win2kddk* 说明：3重DES是使用16字节密钥将8字节明文数据块进行3次DES加密和解密。

DES算法Java实现源代码

*结果为32位数据组f(R0,K1),
*b)第二轮加密迭代：左半边输入L1=R0，右半边输入R1=L0⊕f(R0,K1),由轮函数f实现子密钥
*K2对R1的加密，结果为32位数据组f(R1，K2)，f(R1,K2)与L1模2相加，得到一个32为数据组L1⊕f(R1,K2).
*c)第3到16轮迭代分别用密钥K3，K4……K16进行。4.再经过逆初始置换IP-1，将数据打乱重排，生成64位密文。
{ 9, 14, 15, 5, 2, 8, 12, 3, 7, 0, 4, 10, 1, 13, 11, 6 },
{ 4, 3, 2, 12, 9, 5, 15, 10, 11, 14, 1, 7, 6, 0, 8, 13 } },
{ // S_Box[7]
{ 4, 11, 2, 14, 15, 0, 8, 13, 3, 12, 9, 7, 5, 10, 6, 1 },
package des;
/**
*加密过程：
* 1.初始置换IP：将明文顺序打乱重新排列，置换输出为64位。
* 2.将置换输出的64位明文分成左右凉拌，左一半为L0，右一半称为R0，各32位。
*3。计算函数的16轮迭代。
*a）第一轮加密迭代：左半边输入L0，右半边输入R0：由轮函数f实现子密钥K1对R0的加密，
{ 13, 0, 11, 7, 4, 9, 1, 10, 14, 3, 5, 12, 2, 15, 8, 6 },
{ 1, 4, 11, 13, 12, 3, 7, 14, 10, 15, 6, 8, 0, 5, 9, 2 },
{ 6, 11, 13, 8, 1, 4, 10, 7, 9, 5, 0, 15, 14, 2, 3, 12 } },
10, 11, 12, 13, 12, 13, 14, 15, 16, 17, 16, 17, 18, 19, 20, 21, 20,

des加密算法python代码

序号1：什么是DES加密算法？DES（Data Encryption Standard）是一种对称密钥加密算法，由IBM研制并于1977年被美国国家标准局（NBS）确定为联邦数据处理标准（FIPS）的一部分。

DES算法使用56位的密钥对64位的数据进行加密，经过多轮的置换、替换和移位运算后，得到密文。

DES算法已经被AES算法所代替，但在一些旧系统中仍然在使用。

序号2：DES加密算法的Python实现下面是一个简单的使用Python实现DES加密算法的例子：```pythonfrom Crypto.Cipher import DESfrom Crypto.Random import get_random_bytesdef des_encrypt(key, data):cipher = DES.new(key, DES.MODE_ECB)padded_data = data + b'\0' * (8 - len(data) % 8)encrypted_data = cipher.encrypt(padded_data)return encrypted_datadef des_decrypt(key, encrypted_data):cipher = DES.new(key, DES.MODE_ECB)decrypted_data = cipher.decrypt(encrypted_data).rstrip(b'\0') return decrypted_datakey = get_random_bytes(8)data = b'This is a test'encrypted_data = des_encrypt(key, data)decrypted_data = des_decrypt(key, encrypted_data)print('Original data:', data)print('Encrypted data:', encrypted_data)print('Decrypted data:', decrypted_data)```序号3：代码解读3.1 导入必要的模块```pythonfrom Crypto.Cipher import DESfrom Crypto.Random import get_random_bytes```在这行代码中，我们使用了`Crypto.Cipher`模块中的DES类和`Crypto.Random`模块的`get_random_bytes`函数。

DES算法代码及实验报告

DES算法代码及实验报告DES算法（Data Encryption Standard，数据加密标准）是一种对称密钥加密算法，由美国国家标准局于1977年发布，在许多加密场合广泛使用。

该算法的设计者是IBM的Horst Feistel。

DES算法使用的是分组密码的方式，即将明文划分成64位的明文块，并使用56位的密钥进行加密。

DES算法的加密和解密过程都是通过一系列的迭代运算实现的，其中包括置换、替换和移位操作，从而达到加密数据和解密数据的目的。

以下是用Python实现的DES算法代码：```pythonimport binasciifrom Crypto.Cipher import DESdef des_encrypt(key, plaintext):cipher = DES.new(key, DES.MODE_ECB)encrypted = cipher.encrypt(plaintext)return binascii.hexlify(encrypted).decodedef des_decrypt(key, ciphertext):cipher = DES.new(key, DES.MODE_ECB)decrypted = cipher.decrypt(binascii.unhexlify(ciphertext))return decrypted.decode#示例代码plaintext = b'this is a test'ciphertext = des_encrypt(key, plaintext)print(f'Ciphertext: {ciphertext}')decryptedtext = des_decrypt(key, ciphertext)print(f'Decryptedtext: {decryptedtext}')```上述代码使用了`pycryptodome`库提供的DES加密算法实现。

DES算法源代码

DES算法源代码DES（Data Encryption Standard）是一种对称加密算法，使用相同的密钥对数据进行加密和解密。

它在1977年被美国联邦信息处理标准（FIPS）采纳为联邦标准，至今仍然在很多场景中广泛使用。

以下是一个使用Python实现DES算法的源代码：```pythonfrom Crypto.Cipher import DESfrom Crypto.Random import get_random_bytes# 生成一个由字节（byte）组成的密钥def generate_key(:return get_random_bytes(8)#使用给定的密钥加密数据def encrypt(key, data):cipher = DES.new(key, DES.MODE_ECB)#如果数据的长度不是8的倍数，需要进行填充if len(data) % 8 != 0:data += b'\x00' * (8 - len(data) % 8)ciphertext = cipher.encrypt(data)return ciphertext#使用给定的密钥解密数据def decrypt(key, ciphertext):cipher = DES.new(key, DES.MODE_ECB)data = cipher.decrypt(ciphertext)#去除填充数据data = data.rstrip(b'\x00')return data#测试代码key = generate_keyplaintext = b'This is a test message.'ciphertext = encrypt(key, plaintext)decrypted_text = decrypt(key, ciphertext)print('Key:', key)print('Plaintext:', plaintext)print('Ciphertext:', ciphertext)print('Decrypted Text:', decrypted_text)```这段代码使用Python的`Crypto`库中的`DES`模块来实现DES加密和解密。

C语言实现DES加密解密算法

C语言实现DES加密解密算法
最近几十年里，DES（Data Encryption Standard）算法的发展起到
了极其重要的作用。

Des算法是一种基于分组密码的算法。

算法将64位
的明文数据块按位分组成8个字节，每一组以8位为单位转换成一个64
位的密文数据块，采用16轮的分组加密，每次密码变化，保证加密强度。

本文详细介绍了DES算法的C语言实现，并分别介绍了加解密算法的实现
步骤以及DES加解密测试过程。

一、DES算法C语言实现
1.函数原型
DES算法的实现包括加密和解密函数，函数原型如下：
unsigned char* DesEncrypt(unsigned char *src, unsigned char
*key); // DES加密函数
unsigned char* DesDecrypt(unsigned char *src, unsigned char
*key); // DES解密函数
输入参数src是指明文源数据，key是加解密密钥，输出参数为一个
指向加解密结果的字符串指针。

2.加解密算法
（1）DES加密算法
DES加密算法步骤如下：
（i）初始置换：将64位明文块做一次IP置换得到L0R0。

（ii）迭代轮换：对L0R0经过16次迭代轮换后，最终结果为
L16R16
（iii）逆置换：L16R16进行逆置换得到64位密文。

（2）DES解密算法
DES解密算法步骤和DES加密算法步骤是一样的，只是将置换步骤改为逆置换，将轮换步骤改为逆轮换即可。

三、DES加解密测试
1.程序测试
在C语言编写完DES加解密算法之后。

DES加密算法的C语言实现

DES加密算法的C语言实现DES（Data Encryption Standard）是一种对称密钥加密算法，它的核心思想是将明文分成64位的数据块，并通过一系列的轮次操作对数据块进行加密，最终得到密文。

下面是一种用C语言实现DES加密算法的示例代码：```c#include <stdio.h>unsigned char initial_permutation(unsigned char block)unsigned char result = 0;result ，= (block & 0x80) >> 7;result ，= (block & 0x40) >> 5;result ，= (block & 0x20) >> 3;result ，= (block & 0x10) >> 1;result ，= (block & 0x08) << 1;result ，= (block & 0x04) << 3;result ，= (block & 0x02) << 5;result ，= (block & 0x01) << 7;return result;unsigned char final_permutation(unsigned char block)unsigned char result = 0;result ，= (block & 0x80) >> 7;result ，= (block & 0x40) >> 5;result ，= (block & 0x20) >> 3;result ，= (block & 0x10) >> 1;result ，= (block & 0x08) << 1;result ，= (block & 0x04) << 3;result ，= (block & 0x02) << 5;result ，= (block & 0x01) << 7;return result;void des_encrypt(unsigned char* plaintext, unsigned char* key, unsigned char* ciphertext)unsigned char block;unsigned char round_key;unsigned char i;// Initial Permutationblock = initial_permutation(*plaintext);// Round Permutationfor (i = 0; i < 16; i++)round_key = key[i];block ^= round_key;block = substitution(block);block = permutation(block);}// Final Permutation*ciphertext = final_permutation(block);int maiunsigned char plaintext = 0x55; // 明文unsigned char key[16] = {0x12, 0x34, 0x56, 0x78, 0x9A, 0xBC, 0xDE, 0xEF, 0xFE, 0xDC, 0xBA, 0x98, 0x76, 0x54, 0x32, 0x10}; // 密钥unsigned char ciphertext;des_encrypt(&plaintext, key, &ciphertext);printf("明文: 0x%02X\n", plaintext);printf("密钥: ");for (unsigned char i = 0; i < 16; i++)printf("%02X ", key[i]);}printf("\n");printf("密文: 0x%02X\n", ciphertext);return 0;```上述代码实现了DES算法的加密功能。