私はcとJavaの間で暗号化/復号化することに夢中になっていますが、これまでのところ、Javaの暗号化された文字列とcの暗号化された文字列は同じようには見えません。私はbase64のエンコード/デコードを調査しましたが、javaとcのライブラリを見つけることに夢中になった後、それぞれのbase64の結果は異なって見えました！これは、Java UTF16文字列間の変換、JavaでのByteの保存、またはAESオプション（128/256キー、PK5パディング、または誰が何を知っているか）、あるいは端末のUTF8変換、または上記のばかげた組み合わせの問題だと思います。これまでのところ、次のようになります。
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
私はここで誰かから低レベルのコーディングに本当に助けが必要だと思います。以下はそれぞれJavaとcのコードです。
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");
}
}
と
#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;
}