2012-02-27 05:48:43 +08:00
|
|
|
|
/*
|
|
|
|
|
Copyright (C) 2011-2012 de4dot@gmail.com
|
|
|
|
|
|
|
|
|
|
This file is part of de4dot.
|
|
|
|
|
|
|
|
|
|
de4dot is free software: you can redistribute it and/or modify
|
|
|
|
|
it under the terms of the GNU General Public License as published by
|
|
|
|
|
the Free Software Foundation, either version 3 of the License, or
|
|
|
|
|
(at your option) any later version.
|
|
|
|
|
|
|
|
|
|
de4dot is distributed in the hope that it will be useful,
|
|
|
|
|
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
|
|
|
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
|
|
|
GNU General Public License for more details.
|
|
|
|
|
|
|
|
|
|
You should have received a copy of the GNU General Public License
|
|
|
|
|
along with de4dot. If not, see <http://www.gnu.org/licenses/>.
|
|
|
|
|
*/
|
|
|
|
|
|
|
|
|
|
using System.Collections.Generic;
|
|
|
|
|
using System.IO;
|
|
|
|
|
using System.Text;
|
|
|
|
|
using Mono.Cecil;
|
|
|
|
|
using Mono.Cecil.Cil;
|
|
|
|
|
using de4dot.blocks;
|
|
|
|
|
|
|
|
|
|
namespace de4dot.code.deobfuscators.Eazfuscator_NET {
|
|
|
|
|
class StringDecrypter {
|
|
|
|
|
ModuleDefinition module;
|
|
|
|
|
TypeDefinition decryptType;
|
|
|
|
|
MethodDefinition decryptMethod;
|
|
|
|
|
TypeDefinition dataDecrypterType;
|
|
|
|
|
MethodDefinition int64Method;
|
|
|
|
|
short s1, s2, s3;
|
|
|
|
|
int i1, i2, i3, i4, i5, i6, i7;
|
|
|
|
|
ulong l1;
|
|
|
|
|
int m1_i1, m2_i1, m2_i2, m3_i1;
|
|
|
|
|
int token1, token2, token3, token4, token5, token6;
|
|
|
|
|
bool checkMinus2;
|
|
|
|
|
bool usePublicKeyToken;
|
|
|
|
|
int keyLen;
|
|
|
|
|
byte[] theKey;
|
|
|
|
|
int magic1;
|
|
|
|
|
EmbeddedResource encryptedResource;
|
|
|
|
|
BinaryReader reader;
|
|
|
|
|
|
|
|
|
|
public TypeDefinition Type {
|
|
|
|
|
get { return decryptType; }
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
public EmbeddedResource Resource {
|
|
|
|
|
get { return encryptedResource; }
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
public IEnumerable<TypeDefinition> Types {
|
|
|
|
|
get {
|
|
|
|
|
var list = new List<TypeDefinition>();
|
|
|
|
|
list.Add(decryptType);
|
|
|
|
|
list.Add(dataDecrypterType);
|
|
|
|
|
if (int64Method != null)
|
|
|
|
|
list.Add(int64Method.DeclaringType);
|
|
|
|
|
return list;
|
|
|
|
|
}
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
public MethodDefinition Method {
|
|
|
|
|
get { return decryptMethod; }
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
public bool Detected {
|
|
|
|
|
get { return decryptType != null; }
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
public StringDecrypter(ModuleDefinition module) {
|
|
|
|
|
this.module = module;
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
public void find(ISimpleDeobfuscator simpleDeobfuscator) {
|
|
|
|
|
foreach (var type in module.Types) {
|
|
|
|
|
if (DotNetUtils.findFieldType(type, "System.IO.BinaryReader", true) == null)
|
|
|
|
|
continue;
|
|
|
|
|
if (DotNetUtils.findFieldType(type, "System.Collections.Generic.Dictionary`2<System.Int32,System.String>", true) == null)
|
|
|
|
|
continue;
|
|
|
|
|
|
|
|
|
|
foreach (var method in type.Methods) {
|
|
|
|
|
if (!checkDecrypterMethod(method))
|
|
|
|
|
continue;
|
|
|
|
|
|
|
|
|
|
decryptType = type;
|
|
|
|
|
decryptMethod = method;
|
2012-02-27 08:51:44 +08:00
|
|
|
|
if (!findConstants(simpleDeobfuscator)) {
|
|
|
|
|
if (encryptedResource == null)
|
|
|
|
|
Log.w("Could not find encrypted resource. Strings cannot be decrypted.");
|
|
|
|
|
else
|
|
|
|
|
Log.w("Can't decrypt strings. Possibly a new Eazfuscator.NET version.");
|
|
|
|
|
}
|
2012-02-27 05:48:43 +08:00
|
|
|
|
return;
|
|
|
|
|
}
|
|
|
|
|
}
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
static bool checkDecrypterMethod(MethodDefinition method) {
|
|
|
|
|
if (method == null || !method.IsStatic || method.Body == null)
|
|
|
|
|
return false;
|
|
|
|
|
if (!DotNetUtils.isMethod(method, "System.String", "(System.Int32)"))
|
|
|
|
|
return false;
|
|
|
|
|
|
|
|
|
|
foreach (var instr in method.Body.Instructions) {
|
|
|
|
|
if (instr.OpCode != OpCodes.Callvirt)
|
|
|
|
|
continue;
|
|
|
|
|
var calledMethod = instr.Operand as MethodReference;
|
|
|
|
|
if (calledMethod != null && calledMethod.FullName == "System.IO.Stream System.Reflection.Assembly::GetManifestResourceStream(System.String)")
|
|
|
|
|
return true;
|
|
|
|
|
}
|
|
|
|
|
return false;
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
public bool findConstants(ISimpleDeobfuscator simpleDeobfuscator) {
|
|
|
|
|
if (!findResource(decryptMethod))
|
|
|
|
|
return false;
|
|
|
|
|
|
|
|
|
|
simpleDeobfuscator.deobfuscate(decryptMethod);
|
|
|
|
|
|
|
|
|
|
checkMinus2 = DeobUtils.hasInteger(decryptMethod, -2);
|
|
|
|
|
usePublicKeyToken = callsGetPublicKeyToken(decryptMethod);
|
|
|
|
|
|
|
|
|
|
int64Method = findInt64Method(decryptMethod);
|
|
|
|
|
|
|
|
|
|
if (!findShorts(decryptMethod))
|
|
|
|
|
return false;
|
|
|
|
|
if (!findInt3(decryptMethod))
|
|
|
|
|
return false;
|
|
|
|
|
if (!findInt4(decryptMethod))
|
|
|
|
|
return false;
|
|
|
|
|
if (checkMinus2 && !findInt7(decryptMethod))
|
|
|
|
|
return false;
|
|
|
|
|
dataDecrypterType = findDataDecrypterType(decryptMethod);
|
|
|
|
|
if (dataDecrypterType == null)
|
|
|
|
|
return false;
|
|
|
|
|
|
|
|
|
|
if (int64Method != null) {
|
|
|
|
|
if (!findInts(decryptMethod))
|
|
|
|
|
return false;
|
|
|
|
|
if (!findInt64(int64Method))
|
|
|
|
|
return false;
|
|
|
|
|
if (!findInt5())
|
|
|
|
|
return false;
|
|
|
|
|
if (!findInt6())
|
|
|
|
|
return false;
|
|
|
|
|
if (!findMethodInts())
|
|
|
|
|
return false;
|
|
|
|
|
token1 = getToken(-1509110933);
|
|
|
|
|
token2 = getToken(-82806859);
|
|
|
|
|
token3 = getToken(1294352278);
|
|
|
|
|
token4 = getToken(402344241);
|
|
|
|
|
token5 = getToken(-56237163);
|
|
|
|
|
token6 = getToken(1106695601);
|
|
|
|
|
if (token1 == 0 || token2 == 0 || token3 == 0)
|
|
|
|
|
return false;
|
|
|
|
|
if (token4 == 0 || token5 == 0 || token6 == 0)
|
|
|
|
|
return false;
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
initialize();
|
|
|
|
|
|
|
|
|
|
return true;
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
void initialize() {
|
|
|
|
|
reader = new BinaryReader(encryptedResource.GetResourceStream());
|
|
|
|
|
short len = (short)(reader.ReadInt16() ^ s1);
|
|
|
|
|
if (len != 0)
|
|
|
|
|
theKey = reader.ReadBytes(len);
|
|
|
|
|
else
|
|
|
|
|
keyLen = reader.ReadInt16() ^ s2;
|
|
|
|
|
|
|
|
|
|
if (int64Method != null)
|
|
|
|
|
magic1 = (int)getMagic() ^ i1 ^ i2;
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
public string decrypt(int val) {
|
|
|
|
|
while (true) {
|
|
|
|
|
int offset = magic1 ^ i3 ^ val;
|
|
|
|
|
reader.BaseStream.Position = offset;
|
|
|
|
|
byte[] tmpKey;
|
|
|
|
|
if (theKey == null) {
|
|
|
|
|
tmpKey = reader.ReadBytes(keyLen == -1 ? (short)(reader.ReadInt16() ^ s3 ^ offset) : keyLen);
|
|
|
|
|
if (int64Method != null) {
|
|
|
|
|
for (int i = 0; i < tmpKey.Length; i++)
|
|
|
|
|
tmpKey[i] ^= (byte)(magic1 >> ((i & 3) << 3));
|
|
|
|
|
}
|
|
|
|
|
}
|
|
|
|
|
else
|
|
|
|
|
tmpKey = theKey;
|
|
|
|
|
|
|
|
|
|
int flags = i4 ^ magic1 ^ offset ^ reader.ReadInt32();
|
|
|
|
|
if (checkMinus2 && flags == -2) {
|
|
|
|
|
var ary2 = reader.ReadBytes(4);
|
|
|
|
|
val = -(magic1 ^ i7) ^ (ary2[2] | (ary2[0] << 8) | (ary2[3] << 16) | (ary2[1] << 24));
|
|
|
|
|
continue;
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
var bytes = reader.ReadBytes(flags & 0x1FFFFFFF);
|
|
|
|
|
decrypt1(bytes, tmpKey);
|
|
|
|
|
var pkt = module.Assembly.Name.PublicKeyToken;
|
|
|
|
|
if (usePublicKeyToken && pkt != null && pkt.Length != 0) {
|
|
|
|
|
for (int i = 0; i < bytes.Length; i++)
|
|
|
|
|
bytes[i] ^= (byte)((pkt[i & 7] >> 5) + (pkt[i & 7] << 3));
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
if ((flags & 0x40000000) != 0)
|
|
|
|
|
bytes = rld(bytes);
|
|
|
|
|
if ((flags & 0x80000000) != 0) {
|
|
|
|
|
var sb = new StringBuilder(bytes.Length);
|
|
|
|
|
foreach (var b in bytes)
|
|
|
|
|
sb.Append((char)b);
|
|
|
|
|
return sb.ToString();
|
|
|
|
|
}
|
|
|
|
|
else
|
|
|
|
|
return Encoding.Unicode.GetString(bytes);
|
|
|
|
|
}
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
static byte[] rld(byte[] src) {
|
|
|
|
|
var dst = new byte[src[2] + (src[3] << 8) + (src[0] << 16) + (src[1] << 24)];
|
|
|
|
|
int srcIndex = 4;
|
|
|
|
|
int dstIndex = 0;
|
|
|
|
|
int flags = 0;
|
|
|
|
|
int bit = 128;
|
|
|
|
|
while (dstIndex < dst.Length) {
|
|
|
|
|
bit <<= 1;
|
|
|
|
|
if (bit == 256) {
|
|
|
|
|
bit = 1;
|
|
|
|
|
flags = src[srcIndex++];
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
if ((flags & bit) == 0) {
|
|
|
|
|
dst[dstIndex++] = src[srcIndex++];
|
|
|
|
|
continue;
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
int numBytes = (src[srcIndex] >> 2) + 3;
|
|
|
|
|
int copyIndex = dstIndex - ((src[srcIndex + 1] + (src[srcIndex] << 8)) & 0x3FF);
|
|
|
|
|
if (copyIndex < 0)
|
|
|
|
|
break;
|
|
|
|
|
while (dstIndex < dst.Length && numBytes-- > 0)
|
|
|
|
|
dst[dstIndex++] = dst[copyIndex++];
|
|
|
|
|
srcIndex += 2;
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
return dst;
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
static void decrypt1(byte[] dest, byte[] key) {
|
|
|
|
|
byte b = (byte)((key[1] + 7) ^ (dest.Length + 11));
|
|
|
|
|
uint lcg = (uint)((key[0] | key[2] << 8) + (b << 3));
|
|
|
|
|
b += 3;
|
|
|
|
|
ushort xn = 0;
|
|
|
|
|
for (int i = 0; i < dest.Length; i++) {
|
|
|
|
|
if ((i & 1) == 0) {
|
|
|
|
|
lcg = lcgNext(lcg);
|
|
|
|
|
xn = (ushort)(lcg >> 16);
|
|
|
|
|
}
|
|
|
|
|
byte tmp = dest[i];
|
|
|
|
|
dest[i] ^= (byte)(key[1] ^ (byte)xn ^ b);
|
|
|
|
|
b = (byte)(tmp + 3);
|
|
|
|
|
xn >>= 8;
|
|
|
|
|
}
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
static uint lcgNext(uint lcg) {
|
|
|
|
|
return lcg * 214013 + 2531011;
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
uint getMagic() {
|
|
|
|
|
var bytes = new List<byte>();
|
|
|
|
|
if (module.Assembly != null) {
|
|
|
|
|
if (module.Assembly.Name.PublicKeyToken != null)
|
|
|
|
|
bytes.AddRange(module.Assembly.Name.PublicKeyToken);
|
|
|
|
|
bytes.AddRange(Encoding.Unicode.GetBytes(module.Assembly.Name.Name));
|
|
|
|
|
}
|
|
|
|
|
int cm1 = constMethod1();
|
|
|
|
|
int token = int64Method.DeclaringType.MetadataToken.ToInt32();
|
|
|
|
|
bytes.Add((byte)(token >> 24));
|
|
|
|
|
bytes.Add((byte)(cm1 >> 16));
|
|
|
|
|
bytes.Add((byte)(token >> 8));
|
|
|
|
|
bytes.Add((byte)cm1);
|
|
|
|
|
bytes.Add((byte)(token >> 16));
|
|
|
|
|
bytes.Add((byte)(cm1 >> 8));
|
|
|
|
|
bytes.Add((byte)token);
|
|
|
|
|
bytes.Add((byte)(cm1 >> 24));
|
|
|
|
|
|
|
|
|
|
ulong magic = 0;
|
|
|
|
|
foreach (var b in bytes) {
|
|
|
|
|
magic += b;
|
|
|
|
|
magic += magic << 20;
|
|
|
|
|
magic ^= magic >> 12;
|
|
|
|
|
}
|
|
|
|
|
magic += magic << 6;
|
|
|
|
|
magic ^= magic >> 22;
|
|
|
|
|
magic += magic << 30;
|
|
|
|
|
return (uint)magic ^ (uint)l1;
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
bool findResource(MethodDefinition method) {
|
|
|
|
|
encryptedResource = DotNetUtils.getResource(module, DotNetUtils.getCodeStrings(method)) as EmbeddedResource;
|
|
|
|
|
return encryptedResource != null;
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
int getToken(int constant) {
|
|
|
|
|
var method = findNestedTypeMethod(constant);
|
|
|
|
|
if (method == null)
|
|
|
|
|
return 0;
|
|
|
|
|
return method.DeclaringType.MetadataToken.ToInt32();
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
bool findInt5() {
|
|
|
|
|
var consts = getConstants(findNestedTypeMethod(1294352278));
|
|
|
|
|
if (consts.Count != 2)
|
|
|
|
|
return false;
|
|
|
|
|
i5 = consts[1];
|
|
|
|
|
return true;
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
bool findInt6() {
|
|
|
|
|
var consts = getConstants(findNestedTypeMethod(1106695601));
|
|
|
|
|
if (consts.Count != 1)
|
|
|
|
|
return false;
|
|
|
|
|
i6 = consts[0];
|
|
|
|
|
return true;
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
bool findMethodInts() {
|
|
|
|
|
foreach (var type in int64Method.DeclaringType.NestedTypes) {
|
|
|
|
|
var methods = getBinaryIntMethods(type);
|
|
|
|
|
if (methods.Count < 3)
|
|
|
|
|
continue;
|
|
|
|
|
if (!findMethod1Int(methods))
|
|
|
|
|
continue;
|
|
|
|
|
if (!findMethod2Int(methods))
|
|
|
|
|
continue;
|
|
|
|
|
if (!findMethod3Int(methods))
|
|
|
|
|
continue;
|
|
|
|
|
|
|
|
|
|
return true;
|
|
|
|
|
}
|
|
|
|
|
return false;
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
static List<MethodDefinition> getBinaryIntMethods(TypeDefinition type) {
|
|
|
|
|
var list = new List<MethodDefinition>();
|
|
|
|
|
foreach (var method in type.Methods) {
|
|
|
|
|
if (!method.IsStatic || method.Body == null)
|
|
|
|
|
continue;
|
|
|
|
|
if (!DotNetUtils.isMethod(method, "System.Int32", "(System.Int32,System.Int32)"))
|
|
|
|
|
continue;
|
|
|
|
|
|
|
|
|
|
list.Add(method);
|
|
|
|
|
}
|
|
|
|
|
return list;
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
bool findMethod1Int(IEnumerable<MethodDefinition> methods) {
|
|
|
|
|
foreach (var method in methods) {
|
|
|
|
|
if (countInstructions(method, Code.Ldarg_0) != 1)
|
|
|
|
|
continue;
|
|
|
|
|
var constants = getConstants(method);
|
|
|
|
|
if (constants.Count != 1)
|
|
|
|
|
continue;
|
|
|
|
|
|
|
|
|
|
m1_i1 = constants[0];
|
|
|
|
|
return true;
|
|
|
|
|
}
|
|
|
|
|
return false;
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
bool findMethod2Int(IEnumerable<MethodDefinition> methods) {
|
|
|
|
|
foreach (var method in methods) {
|
|
|
|
|
var constants = getConstants(method);
|
|
|
|
|
if (constants.Count != 2)
|
|
|
|
|
continue;
|
|
|
|
|
|
|
|
|
|
m2_i1 = constants[0];
|
|
|
|
|
m2_i2 = constants[1];
|
|
|
|
|
return true;
|
|
|
|
|
}
|
|
|
|
|
return false;
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
bool findMethod3Int(IEnumerable<MethodDefinition> methods) {
|
|
|
|
|
foreach (var method in methods) {
|
|
|
|
|
if (countInstructions(method, Code.Ldarg_0) != 2)
|
|
|
|
|
continue;
|
|
|
|
|
var constants = getConstants(method);
|
|
|
|
|
if (constants.Count != 1)
|
|
|
|
|
continue;
|
|
|
|
|
|
|
|
|
|
m3_i1 = constants[0];
|
|
|
|
|
return true;
|
|
|
|
|
}
|
|
|
|
|
return false;
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
static int countInstructions(MethodDefinition method, Code code) {
|
|
|
|
|
int count = 0;
|
|
|
|
|
foreach (var instr in method.Body.Instructions) {
|
|
|
|
|
if (instr.OpCode.Code == code)
|
|
|
|
|
count++;
|
|
|
|
|
}
|
|
|
|
|
return count;
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
static List<int> getConstants(MethodDefinition method) {
|
|
|
|
|
var list = new List<int>();
|
|
|
|
|
|
|
|
|
|
if (method == null)
|
|
|
|
|
return list;
|
|
|
|
|
|
|
|
|
|
int index = 0;
|
|
|
|
|
var instrs = method.Body.Instructions;
|
|
|
|
|
while (true) {
|
|
|
|
|
int val;
|
|
|
|
|
if (!getNextInt32(method, ref index, out val))
|
|
|
|
|
break;
|
|
|
|
|
|
|
|
|
|
if (index + 1 < instrs.Count && instrs[index].OpCode.Code != Code.Ret)
|
|
|
|
|
list.Add(val);
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
return list;
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
MethodDefinition findNestedTypeMethod(int constant) {
|
|
|
|
|
foreach (var type in int64Method.DeclaringType.NestedTypes) {
|
|
|
|
|
foreach (var method in type.Methods) {
|
|
|
|
|
if (!method.IsStatic || method.Body == null)
|
|
|
|
|
continue;
|
|
|
|
|
|
|
|
|
|
var instrs = method.Body.Instructions;
|
|
|
|
|
for (int i = 0; i < instrs.Count - 1; i++) {
|
|
|
|
|
var ldci4 = instrs[i];
|
|
|
|
|
if (!DotNetUtils.isLdcI4(ldci4))
|
|
|
|
|
continue;
|
|
|
|
|
if (DotNetUtils.getLdcI4Value(ldci4) != constant)
|
|
|
|
|
continue;
|
|
|
|
|
if (instrs[i + 1].OpCode.Code != Code.Ret)
|
|
|
|
|
continue;
|
|
|
|
|
|
|
|
|
|
return method;
|
|
|
|
|
}
|
|
|
|
|
}
|
|
|
|
|
}
|
|
|
|
|
return null;
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
bool findInt64(MethodDefinition method) {
|
|
|
|
|
var instrs = method.Body.Instructions;
|
|
|
|
|
for (int i = 0; i < instrs.Count - 1; i++) {
|
|
|
|
|
var ldci8 = instrs[i];
|
|
|
|
|
if (ldci8.OpCode.Code != Code.Ldc_I8)
|
|
|
|
|
continue;
|
|
|
|
|
|
|
|
|
|
if (instrs[i + 1].OpCode.Code != Code.Xor)
|
|
|
|
|
continue;
|
|
|
|
|
|
|
|
|
|
l1 = (ulong)(long)ldci8.Operand;
|
|
|
|
|
return true;
|
|
|
|
|
}
|
|
|
|
|
return false;
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
static MethodDefinition findInt64Method(MethodDefinition method) {
|
|
|
|
|
foreach (var instr in method.Body.Instructions) {
|
|
|
|
|
if (instr.OpCode.Code != Code.Call)
|
|
|
|
|
continue;
|
|
|
|
|
var calledMethod = instr.Operand as MethodDefinition;
|
|
|
|
|
if (calledMethod == null)
|
|
|
|
|
continue;
|
|
|
|
|
if (!DotNetUtils.isMethod(calledMethod, "System.Int64", "()"))
|
|
|
|
|
continue;
|
|
|
|
|
|
|
|
|
|
return calledMethod;
|
|
|
|
|
}
|
|
|
|
|
return null;
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
static TypeDefinition findDataDecrypterType(MethodDefinition method) {
|
|
|
|
|
foreach (var instr in method.Body.Instructions) {
|
|
|
|
|
if (instr.OpCode.Code != Code.Call)
|
|
|
|
|
continue;
|
|
|
|
|
var calledMethod = instr.Operand as MethodDefinition;
|
|
|
|
|
if (calledMethod == null)
|
|
|
|
|
continue;
|
|
|
|
|
if (!DotNetUtils.isMethod(calledMethod, "System.Byte[]", "(System.Byte[],System.Byte[])"))
|
|
|
|
|
continue;
|
|
|
|
|
|
|
|
|
|
return calledMethod.DeclaringType;
|
|
|
|
|
}
|
|
|
|
|
return null;
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
bool findShorts(MethodDefinition method) {
|
|
|
|
|
int index = 0;
|
|
|
|
|
if (!findShort(method, ref index, ref s1))
|
|
|
|
|
return false;
|
|
|
|
|
if (!findShort(method, ref index, ref s2))
|
|
|
|
|
return false;
|
|
|
|
|
if (!findShort(method, ref index, ref s3))
|
|
|
|
|
return false;
|
|
|
|
|
|
|
|
|
|
return true;
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
bool findShort(MethodDefinition method, ref int index, ref short s) {
|
|
|
|
|
if (!findCallReadInt16(method, ref index))
|
|
|
|
|
return false;
|
|
|
|
|
index++;
|
|
|
|
|
return getInt16(method, ref index, ref s);
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
bool findInts(MethodDefinition method) {
|
|
|
|
|
int index = findIndexFirstIntegerConstant(method);
|
|
|
|
|
if (index < 0)
|
|
|
|
|
return false;
|
|
|
|
|
|
|
|
|
|
if (!getNextInt32(method, ref index, out i1))
|
|
|
|
|
return false;
|
|
|
|
|
int tmp;
|
|
|
|
|
if (!getNextInt32(method, ref index, out tmp))
|
|
|
|
|
return false;
|
|
|
|
|
if (!getNextInt32(method, ref index, out i2))
|
|
|
|
|
return false;
|
|
|
|
|
|
|
|
|
|
return true;
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
bool findInt3(MethodDefinition method) {
|
|
|
|
|
if (int64Method == null)
|
|
|
|
|
return findInt3Old(method);
|
|
|
|
|
return findInt3New(method);
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
// <= 3.1
|
|
|
|
|
bool findInt3Old(MethodDefinition method) {
|
|
|
|
|
var instrs = method.Body.Instructions;
|
|
|
|
|
for (int i = 0; i < instrs.Count - 4; i++) {
|
|
|
|
|
var ldarg0 = instrs[i];
|
|
|
|
|
if (ldarg0.OpCode.Code != Code.Ldarg_0)
|
|
|
|
|
continue;
|
|
|
|
|
|
|
|
|
|
var ldci4 = instrs[i + 1];
|
|
|
|
|
if (!DotNetUtils.isLdcI4(ldci4))
|
|
|
|
|
continue;
|
|
|
|
|
|
|
|
|
|
int index = i + 1;
|
|
|
|
|
int value;
|
|
|
|
|
if (!getInt32(method, ref index, out value))
|
|
|
|
|
continue;
|
|
|
|
|
if (index >= instrs.Count)
|
|
|
|
|
continue;
|
|
|
|
|
|
|
|
|
|
if (instrs[index].OpCode.Code != Code.Xor)
|
|
|
|
|
continue;
|
|
|
|
|
|
|
|
|
|
i3 = value;
|
|
|
|
|
return true;
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
return false;
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
// 3.2+
|
|
|
|
|
bool findInt3New(MethodDefinition method) {
|
|
|
|
|
var instrs = method.Body.Instructions;
|
|
|
|
|
for (int i = 0; i < instrs.Count - 4; i++) {
|
|
|
|
|
var ldarg0 = instrs[i];
|
|
|
|
|
if (ldarg0.OpCode.Code != Code.Ldarg_0)
|
|
|
|
|
continue;
|
|
|
|
|
|
|
|
|
|
var ldci4 = instrs[i + 1];
|
|
|
|
|
if (!DotNetUtils.isLdcI4(ldci4))
|
|
|
|
|
continue;
|
|
|
|
|
|
|
|
|
|
if (instrs[i + 2].OpCode.Code != Code.Xor)
|
|
|
|
|
continue;
|
|
|
|
|
|
|
|
|
|
if (!DotNetUtils.isLdloc(instrs[i + 3]))
|
|
|
|
|
continue;
|
|
|
|
|
|
|
|
|
|
if (instrs[i + 4].OpCode.Code != Code.Xor)
|
|
|
|
|
continue;
|
|
|
|
|
|
|
|
|
|
i3 = DotNetUtils.getLdcI4Value(ldci4);
|
|
|
|
|
return true;
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
return false;
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
bool findInt4(MethodDefinition method) {
|
|
|
|
|
int index = 0;
|
|
|
|
|
if (!findCallReadInt32(method, ref index))
|
|
|
|
|
return false;
|
|
|
|
|
if (!getNextInt32(method, ref index, out i4))
|
|
|
|
|
return false;
|
|
|
|
|
|
|
|
|
|
return true;
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
bool findInt7(MethodDefinition method) {
|
|
|
|
|
int index = -1;
|
|
|
|
|
while (true) {
|
|
|
|
|
index++;
|
|
|
|
|
if (!findCallReadBytes(method, ref index))
|
|
|
|
|
return false;
|
|
|
|
|
if (index <= 0)
|
|
|
|
|
continue;
|
|
|
|
|
var ldci4 = method.Body.Instructions[index - 1];
|
|
|
|
|
if (!DotNetUtils.isLdcI4(ldci4))
|
|
|
|
|
continue;
|
|
|
|
|
if (DotNetUtils.getLdcI4Value(ldci4) != 4)
|
|
|
|
|
continue;
|
|
|
|
|
if (!getNextInt32(method, ref index, out i7))
|
|
|
|
|
return false;
|
|
|
|
|
|
|
|
|
|
return true;
|
|
|
|
|
}
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
static int findIndexFirstIntegerConstant(MethodDefinition method) {
|
|
|
|
|
var instrs = method.Body.Instructions;
|
|
|
|
|
for (int i = 0; i < instrs.Count - 2; i++) {
|
|
|
|
|
var ldci4 = instrs[i];
|
|
|
|
|
if (!DotNetUtils.isLdcI4(ldci4))
|
|
|
|
|
continue;
|
|
|
|
|
|
|
|
|
|
var stloc = instrs[i + 1];
|
|
|
|
|
if (!DotNetUtils.isStloc(stloc))
|
|
|
|
|
continue;
|
|
|
|
|
|
|
|
|
|
var call = instrs[i + 2];
|
|
|
|
|
if (call.OpCode.Code != Code.Call)
|
|
|
|
|
continue;
|
|
|
|
|
var calledMethod = call.Operand as MethodDefinition;
|
|
|
|
|
if (calledMethod == null)
|
|
|
|
|
continue;
|
|
|
|
|
if (!DotNetUtils.isMethod(calledMethod, "System.Int64", "()"))
|
|
|
|
|
continue;
|
|
|
|
|
|
|
|
|
|
return i;
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
return -1;
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
static bool getNextInt32(MethodDefinition method, ref int index, out int val) {
|
|
|
|
|
for (; index < method.Body.Instructions.Count; index++) {
|
|
|
|
|
var instr = method.Body.Instructions[index];
|
|
|
|
|
if (instr.OpCode.Code != Code.Ldc_I4_S && instr.OpCode.Code != Code.Ldc_I4)
|
|
|
|
|
continue;
|
|
|
|
|
|
|
|
|
|
return getInt32(method, ref index, out val);
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
val = 0;
|
|
|
|
|
return false;
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
static bool getInt16(MethodDefinition method, ref int index, ref short s) {
|
|
|
|
|
int val;
|
|
|
|
|
if (!getInt32(method, ref index, out val))
|
|
|
|
|
return false;
|
|
|
|
|
s = (short)val;
|
|
|
|
|
return true;
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
static bool getInt32(MethodDefinition method, ref int index, out int val) {
|
|
|
|
|
val = 0;
|
|
|
|
|
var instrs = method.Body.Instructions;
|
|
|
|
|
if (index >= instrs.Count)
|
|
|
|
|
return false;
|
|
|
|
|
var ldci4 = instrs[index];
|
|
|
|
|
if (ldci4.OpCode.Code != Code.Ldc_I4_S && ldci4.OpCode.Code != Code.Ldc_I4)
|
|
|
|
|
return false;
|
|
|
|
|
|
|
|
|
|
var stack = new Stack<int>();
|
|
|
|
|
stack.Push(DotNetUtils.getLdcI4Value(ldci4));
|
|
|
|
|
|
|
|
|
|
index++;
|
|
|
|
|
for (; index < instrs.Count; index++) {
|
|
|
|
|
int l = stack.Count - 1;
|
|
|
|
|
|
|
|
|
|
var instr = instrs[index];
|
|
|
|
|
switch (instr.OpCode.Code) {
|
|
|
|
|
case Code.Not:
|
|
|
|
|
stack.Push(~stack.Pop());
|
|
|
|
|
break;
|
|
|
|
|
|
|
|
|
|
case Code.Neg:
|
|
|
|
|
stack.Push(-stack.Pop());
|
|
|
|
|
break;
|
|
|
|
|
|
|
|
|
|
case Code.Ldc_I4:
|
|
|
|
|
case Code.Ldc_I4_S:
|
|
|
|
|
case Code.Ldc_I4_0:
|
|
|
|
|
case Code.Ldc_I4_1:
|
|
|
|
|
case Code.Ldc_I4_2:
|
|
|
|
|
case Code.Ldc_I4_3:
|
|
|
|
|
case Code.Ldc_I4_4:
|
|
|
|
|
case Code.Ldc_I4_5:
|
|
|
|
|
case Code.Ldc_I4_6:
|
|
|
|
|
case Code.Ldc_I4_7:
|
|
|
|
|
case Code.Ldc_I4_8:
|
|
|
|
|
case Code.Ldc_I4_M1:
|
|
|
|
|
stack.Push(DotNetUtils.getLdcI4Value(instr));
|
|
|
|
|
break;
|
|
|
|
|
|
|
|
|
|
case Code.Xor:
|
|
|
|
|
if (stack.Count < 2)
|
|
|
|
|
goto done;
|
|
|
|
|
stack.Push(stack.Pop() ^ stack.Pop());
|
|
|
|
|
break;
|
|
|
|
|
|
|
|
|
|
default:
|
|
|
|
|
goto done;
|
|
|
|
|
}
|
|
|
|
|
}
|
|
|
|
|
done:
|
|
|
|
|
while (stack.Count > 1)
|
|
|
|
|
stack.Pop();
|
|
|
|
|
val = stack.Pop();
|
|
|
|
|
return true;
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
static bool callsGetPublicKeyToken(MethodDefinition method) {
|
|
|
|
|
int index = 0;
|
|
|
|
|
return findCall(method, ref index, "System.Byte[] System.Reflection.AssemblyName::GetPublicKeyToken()");
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
static bool findCallReadInt16(MethodDefinition method, ref int index) {
|
|
|
|
|
return findCall(method, ref index, "System.Int16 System.IO.BinaryReader::ReadInt16()");
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
static bool findCallReadInt32(MethodDefinition method, ref int index) {
|
|
|
|
|
return findCall(method, ref index, "System.Int32 System.IO.BinaryReader::ReadInt32()");
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
static bool findCallReadBytes(MethodDefinition method, ref int index) {
|
|
|
|
|
return findCall(method, ref index, "System.Byte[] System.IO.BinaryReader::ReadBytes(System.Int32)");
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
static bool findCall(MethodDefinition method, ref int index, string methodFullName) {
|
|
|
|
|
for (; index < method.Body.Instructions.Count; index++) {
|
|
|
|
|
if (!findCallvirt(method, ref index))
|
|
|
|
|
return false;
|
|
|
|
|
|
|
|
|
|
var calledMethod = method.Body.Instructions[index].Operand as MethodReference;
|
|
|
|
|
if (calledMethod == null)
|
|
|
|
|
continue;
|
|
|
|
|
if (calledMethod.ToString() != methodFullName)
|
|
|
|
|
continue;
|
|
|
|
|
|
|
|
|
|
return true;
|
|
|
|
|
}
|
|
|
|
|
return false;
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
static bool findCallvirt(MethodDefinition method, ref int index) {
|
|
|
|
|
var instrs = method.Body.Instructions;
|
|
|
|
|
for (; index < instrs.Count; index++) {
|
|
|
|
|
var instr = instrs[index];
|
|
|
|
|
if (instr.OpCode.Code != Code.Callvirt)
|
|
|
|
|
continue;
|
|
|
|
|
|
|
|
|
|
return true;
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
return false;
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
int binOp1(int a, int b) {
|
|
|
|
|
return a ^ (b - m1_i1);
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
int binOp2(int a, int b) {
|
|
|
|
|
return (a - m2_i1) ^ (b + m2_i2);
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
int binOp3(int a, int b) {
|
|
|
|
|
return a ^ (b - m3_i1) ^ (a - b);
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
int constMethod1() {
|
|
|
|
|
return binOp3(binOp2(token2, binOp3(token1, token5)), constMethod6());
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
int constMethod2() {
|
|
|
|
|
return binOp1(token3, token4 ^ binOp2(token2, binOp3(token6, constMethod4())));
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
int constMethod3() {
|
|
|
|
|
return binOp3(binOp1(constMethod2() ^ 0x1F74F46E, token4), binOp2(token1 ^ token6, i5));
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
int constMethod4() {
|
|
|
|
|
return binOp3(token4, binOp1(token1, binOp2(token2, binOp3(token3, binOp1(token5, token6)))));
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
int constMethod5() {
|
|
|
|
|
return binOp2(binOp2(constMethod3(), binOp1(token5, constMethod2())), token6);
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
int constMethod6() {
|
|
|
|
|
return binOp1(token6, binOp3(binOp2(token5, token1), binOp3(token3 ^ i6, constMethod5())));
|
|
|
|
|
}
|
|
|
|
|
}
|
|
|
|
|
}
|