Fixed RETDEC-74 and RETDEC-61 (#1003)

* -m

* Remote copy

* Small fix

* fileinfo regression tests succeeded

* Fixed MPRESS decompiler bug related do imports by ordinal

* decompiler no longer gets generic function names from ordinals

* fix doxygen warnings

* Fixed review comments

Co-authored-by: Ladislav Zezula <ladislav.zezula@avast.com>
Co-authored-by: Peter Matula <peter.matula@avast.com>

include/retdec/fileformat/file_format/pe/pe_format_parser.h

@@ -185,7 +185,7 @@ class PeFormatParser
 
 	std::uint32_t getNumberOfImportedLibraries() const
 	{
-		return peFile->impDir().getNumberOfFiles(PeLib::OLDDIR);
+		return peFile->impDir().getNumberOfFiles(false);
 	}
 
 	std::uint32_t getNumberOfDelayImportedLibraries() const
@@ -309,10 +309,10 @@ class PeFormatParser
 	{
 		const auto & imports = peFile->impDir();
 
-		if(index >= imports.getNumberOfFiles(PeLib::OLDDIR))
+		if(index >= imports.getNumberOfFiles(false))
 			return false;
 
-		fileName = imports.getFileName(index, PeLib::OLDDIR);
+		fileName = imports.getFileName(index, false);
 		return true;
 	}
 
@@ -327,51 +327,37 @@ class PeFormatParser
 		return true;
 	}
 
-	std::unique_ptr<PeImport> getImport(unsigned long long fileIndex, unsigned long long importIndex) const
+	std::unique_ptr<PeImport> getImport(std::size_t fileIndex, std::size_t importIndex) const
 	{
 		const PeLib::ImportDirectory & peImports = peFile->impDir();
-		const auto ordinalMask = peFile->imageLoader().getOrdinalMask();
+		const auto imageBase = peFile->imageLoader().getImageBase();
 		const auto bits = peFile->imageLoader().getImageBitability();
+		std::string importName;
+		std::uint32_t ordinalNumber = 0;
+		std::uint32_t patchRva = 0;
+		std::uint16_t importHint = 0;
+		bool isImportByOrdinal = false;
 
-		if(fileIndex >= peImports.getNumberOfFiles(PeLib::OLDDIR) ||
-			importIndex >= peImports.getNumberOfFunctions(fileIndex, PeLib::OLDDIR))
+		if(peImports.getImportedFunction(fileIndex, importIndex, importName, importHint, ordinalNumber, patchRva, isImportByOrdinal, false))
 		{
-			return nullptr;
-		}
+			auto import = std::make_unique<PeImport>(PeImportFlag::None);
 
-		auto isOrdinalNumberValid = true;
-		unsigned long long ordinalNumber = peImports.getFunctionHint(fileIndex, importIndex, PeLib::OLDDIR);
-		if(!ordinalNumber)
-		{
-			const auto firstThunk = peImports.getFirstThunk(fileIndex, importIndex, PeLib::OLDDIR);
-			const auto originalFirstThunk = peImports.getOriginalFirstThunk(fileIndex, importIndex, PeLib::OLDDIR);
-			if(firstThunk & ordinalMask)
-			{
-				ordinalNumber = firstThunk - ordinalMask;
-			}
-			else if(originalFirstThunk & ordinalMask)
-			{
-				ordinalNumber = originalFirstThunk - ordinalMask;
-			}
-			else
+			if(isImportByOrdinal)
 			{
-				isOrdinalNumberValid = false;
+				import->setOrdinalNumber(ordinalNumber);
 			}
-		}
 
-		auto import = std::make_unique<PeImport>(PeImportFlag::None);
-		if(isOrdinalNumberValid)
-		{
-			import->setOrdinalNumber(ordinalNumber);
-		}
-		else
-		{
-			import->invalidateOrdinalNumber();
+			// Note: Even when the function is imported by ordinal, there can be name
+			// Example: WS2_32.dll!@115 -> WSAStartup
+			import->setName(importName);
+
+			import->setLibraryIndex(fileIndex);
+			import->setAddress(imageBase + patchRva);
+			return import;
 		}
-		import->setName(peImports.getFunctionName(fileIndex, importIndex, PeLib::OLDDIR));
-		import->setAddress(peFile->imageLoader().getImageBase() + peImports.getFirstThunk(fileIndex, PeLib::OLDDIR) + importIndex * (bits / 8));
-		import->setLibraryIndex(fileIndex);
-		return import;
+
+		// Out of range
+		return nullptr;
 	}
 
 	std::unique_ptr<PeImport> getDelayImport(unsigned long long fileIndex, unsigned long long importIndex) const

include/retdec/pelib/PeLibAux.h

@@ -1063,13 +1063,16 @@ namespace PeLib
 	{
 		/// The IMAGE_THUNK_DATA struct of an imported function.
 		PELIB_IMAGE_THUNK_DATA itd;
-		/// The hint of an imported function.
-		std::uint16_t hint;
 		/// The function name of an imported function.
 		std::string fname;
+		/// The RVA of the patched address (from the FirstThunk)
+		std::uint32_t patchRva;
+		/// The hint of an imported function (only if imported by name)
+		std::uint16_t hint;
 
 		PELIB_THUNK_DATA()
 		{
+			patchRva = 0;
 			hint = 0;
 		}
 
@@ -1110,16 +1113,16 @@ namespace PeLib
 		PELIB_IMAGE_IMPORT_DESCRIPTOR impdesc;
 		/// The name of an imported DLL.
 		std::string name;
-		/// All original first thunk values of an imported DLL.
-		std::vector<PELIB_THUNK_DATA> originalfirstthunk;
-		/// All first thunk value of an imported DLL.
-		std::vector<PELIB_THUNK_DATA> firstthunk;
+		/// The list of functions imported from the DLL
+		//std::vector<PELIB_THUNK_DATA> originalfirstthunk;
+		//std::vector<PELIB_THUNK_DATA> firstthunk;
+		std::vector<PELIB_THUNK_DATA> thunk_data;
 
 		inline std::uint32_t calculateSize(std::uint32_t pointerSize) const
 		{
 			std::uint32_t totalSize = sizeof(PELIB_IMAGE_IMPORT_DESCRIPTOR) + name.size() + 1;  // descriptor + dllname
 
-			for(const auto & element : originalfirstthunk)
+			for(const auto & element : thunk_data)
 				totalSize += element.calculateSize(pointerSize);
 			return totalSize + pointerSize;                            // Add zero-termination
 		}

include/retdec/utils/ord_lookup.h

@@ -0,0 +1,18 @@
+/**
+ * @file include/retdec/utils/ord_lookup.h
+ * @brief Converts well-known ordinals to function names
+ * @copyright (c) 2017 Avast Software, licensed under the MIT license
+ */
+
+#ifndef RETDEC_UTILS_ORD_LOOKUP_H
+#define RETDEC_UTILS_ORD_LOOKUP_H
+
+namespace retdec {
+namespace utils {
+
+std::string ordLookUp(const std::string& libName, const std::size_t& ordNum, bool forceNameFromOrdinal);
+
+} // namespace utils
+} // namespace retdec
+
+#endif