【发布时间】：2012-05-02 03:17:57
【问题描述】：
我越来越疯狂地在 c 和 Java 之间加密/解密，但到目前为止，Java 中的加密字符串和 c 中的加密字符串看起来不一样。 我已经研究过 base64 编码/解码，但是在疯狂地为 java 和 c 找到一个库之后，各自的 base64 结果看起来不同了！ 我认为这是在 Java UTF16 字符串之间转换、在 java 中保存 Byte 或 AES 选项（128/256 密钥、PK5 填充或谁知道是什么）之间转换的问题，或者可能是终端的 UTF8 转换或上述的荒谬组合。 到目前为止，我得到：
user1@comp1:~/Desktop$ gcc AES.c /usr/lib/libmcrypt.a -lssl -lcrypto -lpthread
user1@comp1:~/Desktop$ /usr/java/jdk1.6.0_25/bin/javac AES.java
user1@comp1:~/Desktop$ ./a.out
Before encryption: test text 123
After encryption: 49 -60 66 43 -8 66 -106 0 -14 -44 3 47 65 127 -110 117
After decryption: test text 123
user1@comp1:~/Desktop$ java AES
Before encryption: test text 123
After encryption: -110 21 23 59 47 120 70 -93 -54 -93 -12 -70 -91 83 -113 85
After decryption: test text 123
我想我真的需要有人帮助我进行低级编码，下面分别是 Java 和 c 的代码：
import java.security.MessageDigest;
import java.util.Arrays;
import javax.crypto.KeyGenerator;
import javax.crypto.SecretKey;
import javax.crypto.spec.SecretKeySpec;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.Cipher;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.spec.SecretKeySpec;
public class AES {
public static void main(String [] args) {
try {
String text = "test text 123";
/*fixed here now it is 128 bits = 16 Bytes*/
String encryptionKey = "E072EDF9534053A0";
System.out.println("Before encryption: " + text);
byte[] cipher = encrypt(text, encryptionKey);
System.out.print("After encryption: ");
for (int i=0; i<cipher.length; i++)
System.out.print(new Integer(cipher[i])+" ");
System.out.println("");
String decrypted = decrypt(cipher, encryptionKey);
System.out.println("After decryption: " + decrypted);
} catch (Exception e) {
e.printStackTrace();
}
}
public static byte[] encrypt(String plainText, String encryptionKey) throws Exception {
Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding", "SunJCE");
SecretKeySpec key = new SecretKeySpec(encryptionKey.getBytes("UTF-8"), "AES");
cipher.init(Cipher.ENCRYPT_MODE, key,new IvParameterSpec(new byte[cipher.getBlockSize()]));
return cipher.doFinal(plainText.getBytes("UTF-8"));
}
public static String decrypt(byte[] cipherText, String encryptionKey) throws Exception{
Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding", "SunJCE");
SecretKeySpec key = new SecretKeySpec(encryptionKey.getBytes("UTF-8"), "AES");
cipher.init(Cipher.DECRYPT_MODE, key,new IvParameterSpec(new byte[cipher.getBlockSize()]));
return new String(cipher.doFinal(cipherText),"UTF-8");
}
}
和
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <mcrypt.h>
#include <math.h>
#include <stdint.h>
#include <stdlib.h>
int main()
{
MCRYPT td, td2;
const char * plaintext = "test text 123";
int i;
char *key; /* created using mcrypt_gen_key */
char *IV;
char * block_buffer;
int blocksize;
int keysize = 16; /* 128 bits == 16 bytes */
size_t* sizet;
key = calloc(1, keysize);
/*below dirty trick to be sure the entire key has been padded with \0's */
strcpy(key, "E072EDF9534053A0");
memset(key, '\0', sizeof(key));
strcpy(key, "E072EDF9534053A0");
/* MCRYPT mcrypt_module_open( char *algorithm, char* algorithm_directory, char* mode, char* mode_directory);
* This function normally returns an encryption descriptor, or MCRYPT_FAILED on error.
*/
td = mcrypt_module_open("rijndael-128", NULL, "cbc", NULL);
/*we need two encryption descriptors td and td2 for decryption*/
td2 = mcrypt_module_open("rijndael-128", NULL, "cbc", NULL);
blocksize = mcrypt_enc_get_block_size(td);
block_buffer = calloc(1, blocksize);
/*below to be sure the entire block_buffer has been padded with \0's */
memset(block_buffer, '\0', blocksize);
IV = malloc(mcrypt_enc_get_iv_size(td));
if ((block_buffer == NULL) || (IV == NULL)) {
fprintf(stderr, "Failed to allocate memory\n");
exit(EXIT_FAILURE);
}
for (i = 0; i < mcrypt_enc_get_iv_size(td); i++) {
IV[i] = 0;
}
/*as we can see both td and td2 get same key and IV*/
mcrypt_generic_init(td, key, keysize, IV);
mcrypt_generic_init(td2, key, keysize, IV);
memset(block_buffer, '\0', sizeof(plaintext));
strcpy(block_buffer, plaintext);
printf("Before encryption: %s\n", block_buffer);
mcrypt_generic (td, block_buffer, blocksize);
printf("After encryption: ");
for (i=0; i < blocksize; i++)
printf("%d ", block_buffer[i]);
printf("\n");
mdecrypt_generic (td2, block_buffer, blocksize);
printf("After decryption: %s\n", block_buffer);
/* deinitialize the encryption thread */
mcrypt_generic_deinit (td);
mcrypt_generic_deinit(td2);
/* Unload the loaded module */
mcrypt_module_close(td);
mcrypt_module_close(td2);
return 0;
}
【问题讨论】：
-
如果我不够清楚，我希望打印到终端的加密字符串在 Java 和 c 输出中看起来相同，这样我稍后将设法在 Java 客户端和 c 服务器之间发送它反过来。
-
您也可以将加密数据打印为十六进制（更容易）
-
我试过了，但是在 c 中打印到十六进制并不是那么简单（我在这里看到了关于 stackoverflow 的讨论，其中有 10 种不同的解决方案可以做到这一点，甚至没有一个提到标准 c 函数！）。除了那个十六进制不是很有效这就是我第一次尝试base64编码的原因，如果你可以让以上两个使用十六进制，我会很感激
-
@dendini 如果你使用 unix（你应该！）你可以使用命令 hexdump 作为过滤器。
-
AES 是 RIJNDAEL-128，而不是 256？
标签： java c cryptography aes mcrypt