Chiffrement utilisant AES-128 sur Android et IPhone (résultat différent)

Je suis en train de chiffrer du texte à l'aide de l'algorithme AES sur le IPhone et Android plates-formes. Mon problème est que, même en utilisant le même chiffrement/déchiffrement de l'algorithme AES-128) et même les variables fixes (clé, IV, mode), j'obtiens des résultats différents sur les deux plates-formes. Je suis avec des exemples de code à partir de deux plates-formes, que j'utilise pour tester le chiffrement/déchiffrement. J'apprécierais un peu d'aide dans la détermination de ce que je fais de mal.

• Clé: “123456789abcdefg”
• IV: “1111111111111111”
• Texte: “HelloThere”
• Mode: “AES/SRC/NoPadding”

Android Code:

public class Crypto {
private final static String HEX = "0123456789ABCDEF";
public static String encrypt(String seed, String cleartext)
throws Exception {
byte[] rawKey = getRawKey(seed.getBytes());
byte[] result = encrypt(rawKey, cleartext.getBytes());
return toHex(result);
}
public static String decrypt(String seed, String encrypted)
throws Exception {
byte[] rawKey = getRawKey(seed.getBytes());
byte[] enc = toByte(encrypted);
byte[] result = decrypt(rawKey, enc);
return new String(result);
}
private static byte[] getRawKey(byte[] seed) throws Exception {
KeyGenerator kgen = KeyGenerator.getInstance("CBC");
SecureRandom sr = SecureRandom.getInstance("SHA1PRNG");
sr.setSeed(seed);
kgen.init(128, sr); //192 and 256 bits may not be available
SecretKey skey = kgen.generateKey();
byte[] raw = skey.getEncoded();
return raw;
}
private static byte[] encrypt(byte[] raw, byte[] clear) throws Exception {
SecretKeySpec skeySpec = new SecretKeySpec(raw, "AES");
Cipher cipher = Cipher.getInstance("AES");
cipher.init(Cipher.ENCRYPT_MODE, skeySpec);
byte[] encrypted = cipher.doFinal(clear);
return encrypted;
}
private static byte[] decrypt(byte[] raw, byte[] encrypted)
throws Exception {
SecretKeySpec skeySpec = new SecretKeySpec(raw, "AES");
Cipher cipher = Cipher.getInstance("AES");
cipher.init(Cipher.DECRYPT_MODE, skeySpec);
byte[] decrypted = cipher.doFinal(encrypted);
return decrypted;
}
public static String toHex(String txt) {
return toHex(txt.getBytes());
}
public static String fromHex(String hex) {
return new String(toByte(hex));
}
public static byte[] toByte(String hexString) {
int len = hexString.length() / 2;
byte[] result = new byte[len];
for (int i = 0; i < len; i++)
result[i] = Integer.valueOf(hexString.substring(2 * i, 2 * i + 2),
16).byteValue();
return result;
}
public static String toHex(byte[] buf) {
if (buf == null)
return "";
StringBuffer result = new StringBuffer(2 * buf.length);
for (int i = 0; i < buf.length; i++) {
appendHex(result, buf[i]);
}
return result.toString();
}
private static void appendHex(StringBuffer sb, byte b) {
sb.append(HEX.charAt((b >> 4) & 0x0f)).append(HEX.charAt(b & 0x0f));
}
}

IPhone (Objective-C), Code:

- (NSData *) transform:(CCOperation) encryptOrDecrypt data:(NSData *) inputData { 
NSData* secretKey = [Cipher md5:cipherKey];
CCCryptorRef cryptor = NULL;
CCCryptorStatus status = kCCSuccess;
uint8_t iv[kCCBlockSizeAES128];
memset((void *) iv, 0x0, (size_t) sizeof(iv));
status = CCCryptorCreate(encryptOrDecrypt, kCCAlgorithmAES128, kCCOptionPKCS7Padding,
[secretKey bytes], kCCKeySizeAES128, iv, &cryptor);
if (status != kCCSuccess) {
return nil;
}
size_t bufsize = CCCryptorGetOutputLength(cryptor, (size_t)[inputData length], true);
void * buf = malloc(bufsize * sizeof(uint8_t));
memset(buf, 0x0, bufsize);
size_t bufused = 0;
size_t bytesTotal = 0;
status = CCCryptorUpdate(cryptor, [inputData bytes], (size_t)[inputData length],
buf, bufsize, &bufused);
if (status != kCCSuccess) {
free(buf);
CCCryptorRelease(cryptor);
return nil;
}
bytesTotal += bufused;
status = CCCryptorFinal(cryptor, buf + bufused, bufsize - bufused, &bufused);
if (status != kCCSuccess) {
free(buf);
CCCryptorRelease(cryptor);
return nil;
}
bytesTotal += bufused;
CCCryptorRelease(cryptor);
return [NSData dataWithBytesNoCopy:buf length:bytesTotal];
}
+ (NSData *) md5:(NSString *) stringToHash {
const char *src = [stringToHash UTF8String];
unsigned char result[CC_MD5_DIGEST_LENGTH];
CC_MD5(src, strlen(src), result);
return [NSData dataWithBytes:result length:CC_MD5_DIGEST_LENGTH];
}

Certains de mes références :

• http://code.google.com/p/aes-encryption-samples/wiki/HowToEncryptWithJava
• http://automagical.rationalmind.net/2009/02/12/aes-interoperability-between-net-and-iphone/
• AES interopérabilité entre .Net et iPhone?

source d'informationauteur UBA_MobileTeam