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我有一個與文件解密相關的特定問題。我發現了一個Java程序，解密特定文件（這是遊戲中的保存文件，你可以在這裏找到這個文件的例子：https://www.adrive.com/public/6DBShx/game.sii），我想把這個程序改寫成C＃ - 這樣我就可以將它整合到不同的程序中我用C＃寫的。 這是我第一次使用加密文件，所以我製作的程序無法正常工作，實際上我不知道如何調試它。我寫的程序有固定的文件路徑 - 這是臨時解決方案。將AES文件解密程序從Java重寫爲C＃
原始的Java程序：
package scsc;
import javax.crypto.Cipher;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.spec.SecretKeySpec;
import java.io.*;
import java.lang.reflect.Field;
import java.nio.charset.Charset;
import java.nio.file.Files;
import java.nio.file.StandardCopyOption;
import java.security.Permission;
import java.security.PermissionCollection;
import java.util.Map;
import java.util.zip.InflaterInputStream;
/*
* Published under the Do What the Fuck You Want to Public License ( http://www.wtfpl.net/)
*/
public class ScsC {
private static byte[] AES_KEY = new byte[]{
(byte) 0x2a, (byte) 0x5f, (byte) 0xcb, (byte) 0x17,
(byte) 0x91, (byte) 0xd2, (byte) 0x2f, (byte) 0xb6,
(byte) 0x02, (byte) 0x45, (byte) 0xb3, (byte) 0xd8,
(byte) 0x36, (byte) 0x9e, (byte) 0xd0, (byte) 0xb2,
(byte) 0xc2, (byte) 0x73, (byte) 0x71, (byte) 0x56,
(byte) 0x3f, (byte) 0xbf, (byte) 0x1f, (byte) 0x3c,
(byte) 0x9e, (byte) 0xdf, (byte) 0x6b, (byte) 0x11,
(byte) 0x82, (byte) 0x5a, (byte) 0x5d, (byte) 0x0a,
};
public static void main(String[] args) throws Exception {
if (args.length < 1) {
System.out.println("ERROR: expecting at least one file.");
} else {
removeCryptographyRestrictions();
for (String filename : args) {
decrypt(filename);
}
}
}
private static void decrypt(String filename) throws Exception {
File scsc = new File(filename);
if (!scsc.isFile() || !scsc.canWrite()) {
throw new IllegalArgumentException(filename + " is not a writable file.");
}
boolean encrypted = isEncrypted(scsc);
if (!encrypted) {
System.out.println(scsc + " does not seem to be encrypted.");
} else {
File decrypted = decrypt(scsc);
Files.copy(decrypted.toPath(), scsc.toPath(), StandardCopyOption.REPLACE_EXISTING);
System.out.println("decrypted: " + scsc);
}
}
private static boolean isEncrypted(File file) throws Exception {
byte[] header = new byte[4];
FileInputStream fis = new FileInputStream(file);
if (fis.read(header) != header.length) {
throw new RuntimeException("could not read header of " + file);
}
fis.close();
String headerAsString = new String(header, Charset.forName("UTF-8"));
return "ScsC".equals(headerAsString);
}
private static File decrypt(File input) throws Exception {
File out = File.createTempFile("scsc-", ".tmp");
out.deleteOnExit();
byte[] data = new byte[(int) (input.length())];
FileInputStream fis = new FileInputStream(input);
if (fis.read(data) != data.length) {
throw new RuntimeException("Could not read " + input + " into memory");
}
fis.close();
byte[] cipherText = new byte[data.length - 0x38];
byte[] iv = new byte[0x10];
System.arraycopy(data, 0x38, cipherText, 0, cipherText.length);
System.arraycopy(data, 0x24, iv, 0, iv.length);
byte[] decrypted = decrypt(cipherText, AES_KEY, iv);
ByteArrayInputStream bis = new ByteArrayInputStream(decrypted);
InflaterInputStream iis = new InflaterInputStream(bis);
InputStreamReader ir = new InputStreamReader(iis);
BufferedReader br = new BufferedReader(ir);
FileOutputStream fos = new FileOutputStream(out);
OutputStreamWriter osw = new OutputStreamWriter(fos);
PrintWriter pw = new PrintWriter(osw);
for (String line = br.readLine(); line != null; line = br.readLine()) {
pw.println(line);
}
pw.close();
br.close();
return out;
}
private static byte[] decrypt(byte[] cipherText, byte[] keyBytes, byte[] iv) throws Exception {
Cipher cipher = Cipher.getInstance("AES/CBC/NoPadding");
SecretKeySpec key = new SecretKeySpec(keyBytes, "AES");
cipher.init(Cipher.DECRYPT_MODE, key, new IvParameterSpec(iv));
return cipher.doFinal(cipherText);
}
private static void removeCryptographyRestrictions() throws Exception {
// taken from http://stackoverflow.com/questions/1179672/unlimited-strength-jce-policy-files
final Class<?> jceSecurity = Class.forName("javax.crypto.JceSecurity");
final Class<?> cryptoPermissions = Class.forName("javax.crypto.CryptoPermissions");
final Class<?> cryptoAllPermission = Class.forName("javax.crypto.CryptoAllPermission");
final Field isRestrictedField = jceSecurity.getDeclaredField("isRestricted");
isRestrictedField.setAccessible(true);
isRestrictedField.set(null, false);
final Field defaultPolicyField = jceSecurity.getDeclaredField("defaultPolicy");
defaultPolicyField.setAccessible(true);
final PermissionCollection defaultPolicy = (PermissionCollection) defaultPolicyField.get(null);
final Field perms = cryptoPermissions.getDeclaredField("perms");
perms.setAccessible(true);
((Map<?, ?>) perms.get(defaultPolicy)).clear();
final Field instance = cryptoAllPermission.getDeclaredField("INSTANCE");
instance.setAccessible(true);
defaultPolicy.add((Permission) instance.get(null));
}
}
我的代碼，我在C＃寫的農產品似乎工作，但並不如預期輸出... 預期的結果應該是可讀的文件（鏈接：https://www.adrive.com/public/E3rsfv/game.sii_decrypted_by_java）
第一解密文件的幾行：
SiiNunit
{
economy : _nameless.0357.B5D0 {
bank: _nameless.0371.CD48
player: _nameless.0369.3070
companies: 811
companies[0]: company.volatile.trameri.esbjerg
companies[1]: company.volatile.bcp.turku
companies[2]: company.volatile.itcc.liege
companies[3]: company.volatile.tree_et.geneve
companies[4]: company.volatile.tree_et.arhus
companies[5]: company.volatile.itcc.jonkoping
companies[6]: company.volatile.kaarfor.poznan
companies[7]: company.volatile.fcp.milano
companies[8]: company.volatile.posped.swansea
companies[9]: company.volatile.tradeaux.lille
companies[10]: company.volatile.euroacres.osnabruck
用C＃解密 - 我不能把許多環節在這裏:(
前幾行：
xڬ�M�$������C��4fcm�o��#=- ��rLV������̪[���<�8�J��F����t��C������:�>������>Ƿ_��Ƿ ��m��~|�9�T����ߦ?�����*[�����X��} ���=����S�������9��Q����?�����~����|���?? O���������ӳx�Y<<����uz�PoAw����w���������������~sz�� ������z|��Wf��ٜ�O�6�/�;I�m���[-����}�������c��T��| ��D��K�8S�ۯ�q�x�~�y�8lN_���)7�������ux��xг���@}l�����15} x�������c��#Ul�>>���͛|�T����>�q�����py�! ����X�'�tW����!��ow�w��۸c�Ə��^κ �ŗ�{�I�P���7���9<| ��O�}�������6_�ؾ=��}�����{RVħ�9��?��i�|A�awz#;���w�Km� %�3a�"~ݜ��9y4�����r�6����ގ_�/ �1<ݍqL����w�����=�l~���H\�y4J������(gU(k��m�S�S���es8��3m Ű,�M��_��~��w� ��S- ��Y|z�KP�P�����:ֆ������G�q��v�&�QLp6��C}<? �G5�cY�����q��)���q�D�|ڪε�i�����XI��>Ӕ_:c�
��~�<�1��h���=���{8m��G�8X��ٞҚB�6�Oۅ�Jy<�>���� ����b�Mu�l�v�W[u
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和類，在C＃創建此：
public partial class Form1 : Form
{
string file_original;
byte[] file_orig_bytes;
public Form1()
{
InitializeComponent();
}
private void button1_Click(object sender, EventArgs e)
{
byte[] AES_KEY = new byte[]{
(byte) 0x2a, (byte) 0x5f, (byte) 0xcb, (byte) 0x17,
(byte) 0x91, (byte) 0xd2, (byte) 0x2f, (byte) 0xb6,
(byte) 0x02, (byte) 0x45, (byte) 0xb3, (byte) 0xd8,
(byte) 0x36, (byte) 0x9e, (byte) 0xd0, (byte) 0xb2,
(byte) 0xc2, (byte) 0x73, (byte) 0x71, (byte) 0x56,
(byte) 0x3f, (byte) 0xbf, (byte) 0x1f, (byte) 0x3c,
(byte) 0x9e, (byte) 0xdf, (byte) 0x6b, (byte) 0x11,
(byte) 0x82, (byte) 0x5a, (byte) 0x5d, (byte) 0x0a,
};
string path = "game.sii";
load_file_to_memory(path);
//decrypt_file(AES_KEY);
byte[] iv = new byte[0x10];
byte[] cipherText = new byte[file_orig_bytes.Length - 0x38];
Array.Copy(file_orig_bytes, 0x38, cipherText, 0, cipherText.Length);
Array.Copy(file_orig_bytes, 0x24, iv, 0, iv.Length);
string new_file = DecryptStringFromBytes_Aes(cipherText, AES_KEY, iv);
int a;
}
private void load_file_to_memory(string path)
{
file_original = File.ReadAllText(path);
file_orig_bytes = File.ReadAllBytes(path);
int i;
}
static string DecryptStringFromBytes_Aes(byte[] cipherText, byte[] Key
, byte[] IV)
{
// Check arguments.
if (cipherText == null || cipherText.Length <= 0)
throw new ArgumentNullException("cipherText");
if (Key == null || Key.Length <= 0)
throw new ArgumentNullException("Key");
if (IV == null || IV.Length <= 0)
throw new ArgumentNullException("Key");
// Declare the string used to hold
// the decrypted text.
string plaintext = null;
// Create an Aes object
// with the specified key and IV.
using (Aes aesAlg = Aes.Create())
{
aesAlg.Key = Key;
aesAlg.IV = IV;
// Create a decrytor to perform the stream transform.
ICryptoTransform decryptor = aesAlg.CreateDecryptor(aesAlg.Key, aesAlg.IV);
// Create the streams used for decryption.
using (MemoryStream msDecrypt = new MemoryStream(cipherText))
{
using (CryptoStream csDecrypt = new CryptoStream(msDecrypt, decryptor, CryptoStreamMode.Read))
{
using (StreamReader srDecrypt = new StreamReader(csDecrypt))
{
// Read the decrypted bytes from the decrypting stream
// and place them in a string.
plaintext = srDecrypt.ReadToEnd();
}
}
}
}
return plaintext;
}
任何幫助？謝謝
爲什麼你不使用框架現有的類https://msdn.microsoft.com/en-us/library/system.security.cryptography.aes(v=vs.110).aspx？ – bdn02
@ bdn02 AES和Rijndael是128的默認塊大小的代名詞。 –
我用默認示例重寫了它 - 它效果更好 - 沒有空字符串。代碼附在答案中（我應該編輯原始文章嗎？），但仍然沒有原始結果。返回字符串似乎仍然被加密... –