Example #1
0
            public MethodBodyHeader decrypt(uint bodyOffset, out byte[] code, out byte[] extraSections)
            {
                peImage.Reader.BaseStream.Position = bodyOffset;
                var mbHeader = MethodBodyParser.parseMethodBody(peImage.Reader, out code, out extraSections);

                blowfish.decrypt(code);
                return(mbHeader);
            }
        public bool decrypt(MyPEImage peImage, ref DumpedMethods dumpedMethods)
        {
            dumpedMethods = new DumpedMethods();

            bool decrypted = false;

            var methodDef = peImage.DotNetFile.MetaData.TablesStream.MethodTable;

            for (uint rid = 1; rid <= methodDef.Rows; rid++)
            {
                var dm = new DumpedMethod();
                peImage.readMethodTableRowTo(dm, rid);

                if (dm.mdRVA == 0)
                {
                    continue;
                }
                uint bodyOffset = peImage.rvaToOffset(dm.mdRVA);

                peImage.Reader.Position = bodyOffset;
                var mbHeader = MethodBodyParser.parseMethodBody(peImage.Reader, out dm.code, out dm.extraSections);
                peImage.updateMethodHeaderInfo(dm, mbHeader);

                if (dm.code.Length < 6 || dm.code[0] != 0x2A || dm.code[1] != 0x2A)
                {
                    continue;
                }

                int seed = BitConverter.ToInt32(dm.code, 2);
                Array.Copy(newCodeHeader, dm.code, newCodeHeader.Length);
                if (seed == 0)
                {
                    decrypt(dm.code);
                }
                else
                {
                    decrypt(dm.code, seed);
                }

                dumpedMethods.add(dm);
                decrypted = true;
            }

            return(decrypted);
        }
Example #3
0
        DumpedMethods decryptMethods()
        {
            var dumpedMethods = new DumpedMethods();

            var peImage     = decrypterInfo.peImage;
            var methodInfos = new MethodInfos(decrypterInfo.mainType, peImage, decrypterInfo.peHeader, decrypterInfo.mcKey);

            methodInfos.initializeInfos();

            var methodDef = peImage.DotNetFile.MetaData.TablesStream.MethodTable;

            for (uint rid = 1; rid <= methodDef.Rows; rid++)
            {
                var dm = new DumpedMethod();
                peImage.readMethodTableRowTo(dm, rid);

                var info = methodInfos.lookup(dm.mdRVA);
                if (info == null)
                {
                    continue;
                }

                ushort magic = peImage.readUInt16(dm.mdRVA);
                if (magic != 0xFFF3)
                {
                    continue;
                }

                var mbHeader = MethodBodyParser.parseMethodBody(MemoryImageStream.Create(info.body), out dm.code, out dm.extraSections);
                peImage.updateMethodHeaderInfo(dm, mbHeader);

                dumpedMethods.add(dm);
            }

            return(dumpedMethods);
        }
Example #4
0
		public bool decrypt(MyPEImage peImage, ISimpleDeobfuscator simpleDeobfuscator, ref DumpedMethods dumpedMethods, Dictionary<uint, byte[]> tokenToNativeCode, bool unpackedNativeFile) {
			if (encryptedResource.Method == null)
				return false;

			encryptedResource.init(simpleDeobfuscator);
			if (!encryptedResource.FoundResource)
				return false;
			var methodsData = encryptedResource.decrypt();

			bool hooksJitter = findDnrCompileMethod(encryptedResource.Method.DeclaringType) != null;

			xorKey = getXorKey();
			xorEncrypt(methodsData);

			var methodsDataReader = MemoryImageStream.Create(methodsData);
			int patchCount = methodsDataReader.ReadInt32();
			int mode = methodsDataReader.ReadInt32();

			int tmp = methodsDataReader.ReadInt32();
			methodsDataReader.Position -= 4;
			if ((tmp & 0xFF000000) == 0x06000000) {
				// It's method token + rva. DNR 3.7.0.3 (and earlier?) - 3.9.0.1
				methodsDataReader.Position += 8L * patchCount;
				patchCount = methodsDataReader.ReadInt32();
				mode = methodsDataReader.ReadInt32();

				patchDwords(peImage, methodsDataReader, patchCount);
				while (methodsDataReader.Position < methodsData.Length - 1) {
					uint token = methodsDataReader.ReadUInt32();
					int numDwords = methodsDataReader.ReadInt32();
					patchDwords(peImage, methodsDataReader, numDwords / 2);
				}
			}
			else if (!hooksJitter || mode == 1) {
				// DNR 3.9.8.0, 4.0, 4.1, 4.2, 4.3, 4.4

				// If it's .NET 1.x, then offsets are used, not RVAs.
				bool useOffsets = unpackedNativeFile && module.IsClr1x;

				patchDwords(peImage, methodsDataReader, patchCount);
				while (methodsDataReader.Position < methodsData.Length - 1) {
					uint rva = methodsDataReader.ReadUInt32();
					uint token = methodsDataReader.ReadUInt32();	// token, unknown, or index
					int size = methodsDataReader.ReadInt32();
					if (size > 0) {
						var newData = methodsDataReader.ReadBytes(size);
						if (useOffsets)
							peImage.dotNetSafeWriteOffset(rva, newData);
						else
							peImage.dotNetSafeWrite(rva, newData);
					}
				}
			}
			else {
				// DNR 4.0 - 4.5 (jitter is hooked)

				var methodDef = peImage.DotNetFile.MetaData.TablesStream.MethodTable;
				var rvaToIndex = new Dictionary<uint, int>((int)methodDef.Rows);
				uint offset = (uint)methodDef.StartOffset;
				for (int i = 0; i < methodDef.Rows; i++) {
					uint rva = peImage.offsetReadUInt32(offset);
					offset += methodDef.RowSize;
					if (rva == 0)
						continue;

					if ((peImage.readByte(rva) & 3) == 2)
						rva++;
					else
						rva += (uint)(4 * (peImage.readByte(rva + 1) >> 4));
					rvaToIndex[rva] = i;
				}

				patchDwords(peImage, methodsDataReader, patchCount);
				int count = methodsDataReader.ReadInt32();
				dumpedMethods = new DumpedMethods();
				while (methodsDataReader.Position < methodsData.Length - 1) {
					uint rva = methodsDataReader.ReadUInt32();
					uint index = methodsDataReader.ReadUInt32();
					bool isNativeCode = index >= 0x70000000;
					int size = methodsDataReader.ReadInt32();
					var methodData = methodsDataReader.ReadBytes(size);

					int methodIndex;
					if (!rvaToIndex.TryGetValue(rva, out methodIndex)) {
						Logger.w("Could not find method having code RVA {0:X8}", rva);
						continue;
					}

					uint methodToken = 0x06000001 + (uint)methodIndex;

					if (isNativeCode) {
						totalEncryptedNativeMethods++;
						if (tokenToNativeCode != null)
							tokenToNativeCode[methodToken] = methodData;

						// Convert return true / false methods. The others are converted to
						// throw 0xDEADCODE.
						if (DeobUtils.isCode(nativeLdci4, methodData)) {
							uint val = BitConverter.ToUInt32(methodData, 4);
							// ldc.i4 XXXXXXXXh / ret
							methodData = new byte[] { 0x20, 0, 0, 0, 0, 0x2A };
							methodData[1] = (byte)val;
							methodData[2] = (byte)(val >> 8);
							methodData[3] = (byte)(val >> 16);
							methodData[4] = (byte)(val >> 24);
						}
						else if (DeobUtils.isCode(nativeLdci4_0, methodData)) {
							// ldc.i4.0 / ret
							methodData = new byte[] { 0x16, 0x2A };
						}
						else {
							tokenToNativeMethod[methodToken] = methodData;

							// ldc.i4 0xDEADCODE / conv.u4 / throw
							methodData = new byte[] { 0x20, 0xDE, 0xC0, 0xAD, 0xDE, 0x6D, 0x7A };
						}
					}

					var dm = new DumpedMethod();
					peImage.readMethodTableRowTo(dm, MDToken.ToRID(methodToken));
					dm.code = methodData;

					var codeReader = peImage.Reader;
					codeReader.Position = peImage.rvaToOffset(dm.mdRVA);
					byte[] code;
					var mbHeader = MethodBodyParser.parseMethodBody(codeReader, out code, out dm.extraSections);
					peImage.updateMethodHeaderInfo(dm, mbHeader);

					dumpedMethods.add(dm);
				}
			}

			return true;
		}
Example #5
0
        public bool decrypt(PeImage peImage, ref DumpedMethods dumpedMethods)
        {
            dumpedMethods = new DumpedMethods();

            bool decrypted = false;

            var  metadataTables  = peImage.Cor20Header.createMetadataTables();
            var  methodDef       = metadataTables.getMetadataType(MetadataIndex.iMethodDef);
            uint methodDefOffset = methodDef.fileOffset;

            for (int i = 0; i < methodDef.rows; i++, methodDefOffset += methodDef.totalSize)
            {
                uint bodyRva = peImage.offsetReadUInt32(methodDefOffset);
                if (bodyRva == 0)
                {
                    continue;
                }
                uint bodyOffset = peImage.rvaToOffset(bodyRva);

                var dm = new DumpedMethod();
                dm.token = (uint)(0x06000001 + i);

                byte[] code, extraSections;
                peImage.Reader.BaseStream.Position = bodyOffset;
                var mbHeader = MethodBodyParser.parseMethodBody(peImage.Reader, out code, out extraSections);

                if (code.Length < 6 || code[0] != 0x2A || code[1] != 0x2A)
                {
                    continue;
                }
                dm.code          = code;
                dm.extraSections = extraSections;

                int seed = BitConverter.ToInt32(code, 2);
                Array.Copy(newCodeHeader, code, newCodeHeader.Length);
                if (seed == 0)
                {
                    decrypt(code);
                }
                else
                {
                    decrypt(code, seed);
                }

                dm.mdImplFlags = peImage.offsetReadUInt16(methodDefOffset + (uint)methodDef.fields[1].offset);
                dm.mdFlags     = peImage.offsetReadUInt16(methodDefOffset + (uint)methodDef.fields[2].offset);
                dm.mdName      = peImage.offsetRead(methodDefOffset + (uint)methodDef.fields[3].offset, methodDef.fields[3].size);
                dm.mdSignature = peImage.offsetRead(methodDefOffset + (uint)methodDef.fields[4].offset, methodDef.fields[4].size);
                dm.mdParamList = peImage.offsetRead(methodDefOffset + (uint)methodDef.fields[5].offset, methodDef.fields[5].size);

                dm.mhFlags          = mbHeader.flags;
                dm.mhMaxStack       = mbHeader.maxStack;
                dm.mhCodeSize       = (uint)dm.code.Length;
                dm.mhLocalVarSigTok = mbHeader.localVarSigTok;

                dumpedMethods.add(dm);
                decrypted = true;
            }

            return(decrypted);
        }
Example #6
0
 protected MethodBodyHeader getCodeBytes(byte[] methodBody, out byte[] code, out byte[] extraSections)
 {
     return(MethodBodyParser.parseMethodBody(new BinaryReader(new MemoryStream(methodBody)), out code, out extraSections));
 }
Example #7
0
 public override MethodBodyHeader decrypt(MethodInfo methodInfo, out byte[] code, out byte[] extraSections)
 {
     peImage.Reader.BaseStream.Position = endOfMetadata + methodInfo.codeOffs;
     return(MethodBodyParser.parseMethodBody(peImage.Reader, out code, out extraSections));
 }
 public override MethodBodyHeader decrypt(MethodInfo methodInfo, out byte[] code, out byte[] extraSections)
 {
     peImage.Reader.Position = peImage.rvaToOffset(methodInfo.codeOffs);
     return(MethodBodyParser.parseMethodBody(peImage.Reader, out code, out extraSections));
 }
 protected MethodBodyHeader getCodeBytes(byte[] methodBody, out byte[] code, out byte[] extraSections)
 {
     return(MethodBodyParser.parseMethodBody(MemoryImageStream.Create(methodBody), out code, out extraSections));
 }