patterns/ne: Adding pattern file for NE executables (#58)

* Update pe.hexpat

Implementing a number of things and fixing others

* Update pe.hexpat

Adding the readonlyData pattern

* Update pe.hexpat

Testing putting the number of tabs on Github to 4 instead of 8 (so that comments on the code for the Sections don't break)

* Update pe.hexpat

Reverting change that turned out to be needless

* Update pe.hexpat

Actually sending the `products[while($ != richHeaderEndPosition)]` to `products[while($ < richHeaderEndPosition)]` change

* Add files via upload

Adding NE test file

* Add files via upload

Adding NE pattern file

* Update ne.hexpat

Fixing the error with the entry table assignment

* Update README.md

Added the NE pattern file to the list of patterns

README.md

@@ -11,6 +11,7 @@ Hex patterns, include patterns and magic files for the use with the ImHex Hex Ed
 | BMP  | `image/bmp` | [`patterns/bmp.hexpat`](patterns/bmp.hexpat) | OS2/Windows Bitmap files |
 | ELF  | `application/x-executable` | [`patterns/elf.hexpat`](patterns/elf.hexpat) | ELF header in elf binaries |
 | PE   | `application/x-dosexec` | [`patterns/pe.hexpat`](patterns/pe.hexpat) | PE header, COFF header, Standard COFF fields and Windows Specific fields |
+| NE   | | [`patterns/ne.hexpat`](patterns/ne.hexpat) | NE header and Standard NE fields |
 | Intel HEX  | | [`patterns/intel_hex.hexpat`](patterns/intel_hex.hexpat) | [Intel hexadecimal object file format definition]("https://en.wikipedia.org/wiki/Intel_HEX") |
 | MIDI | `audio/midi` | [`patterns/midi.hexpat`](patterns/midi.hexpat) | MIDI header, event fields provided |
 | WAV  | `audio/wav`  | [`patterns/wav.hexpat`](patterns/wav.hexpat)  | RIFF header, WAVE header, PCM header |

patterns/ne.hexpat

@@ -0,0 +1,264 @@
+#include <std/mem.pat>
+
+#pragma bitfield_order right_to_left
+
+struct DOSHeader {
+    char signature[2];
+    u16 lastPageSize;
+    u16 numberOfPages;
+    u16 relocations;
+    u16 headerSizeInParagraphs;
+    u16 minimumAllocatedParagraphs;
+    u16 maximumAllocatedParagraphs;
+    u16 initialSSValue;
+    u16 initialRelativeSPValue;
+    u16 checksum;
+    u16 initialRelativeIPValue;
+    u16 initialCSValue;
+    u16 relocationsTablePointer;
+    u16 overlayNumber;
+    u8 overlayInformation[0x20];
+    u32 neHeaderPointer;
+};
+
+u16 dosMessageOffset;
+u16 pointedCodeOffset;
+
+fn finddosmessage() {
+	for (u8 i = 0, $+i < std::mem::read_unsigned(0x3C, 4), i = i + 1) {
+		if (std::mem::read_unsigned($+i, 1) == 0xBA) { // MOV instruction
+			dosMessageOffset = std::mem::read_unsigned($+i+1, 2);
+			break;
+		}
+	}
+};
+
+fn findpointingcode() {
+	for (u8 i = 0, $+i < std::mem::read_unsigned(0x3C, 4), i = i + 1) {
+		if (std::mem::read_unsigned($+i, 1) == 0xE8) { // CALL instruction
+			pointedCodeOffset = std::mem::read_unsigned($+i+1, 2);
+			return true;
+		}
+	}
+	return false;
+};
+
+fn isdosdata(char c) {
+	return c == 0x0D || c == '$';
+};
+
+struct DOSStub {
+	if (findpointingcode()) {
+    	u8 pointingCode[3];
+    	u8 code[while(std::mem::read_unsigned($, 1) != 0x00)] @ addressof(this) + pointedCodeOffset + 3;
+		char message[while(!isdosdata(std::mem::read_unsigned($, 1)))];
+		char data[while(std::mem::read_string($-1, 1) != "$")];
+    }
+    else {
+		finddosmessage();
+		if (dosMessageOffset > 0) {
+			u8 code[while($ != addressof(this) + dosMessageOffset)];
+			char message[while(!isdosdata(std::mem::read_unsigned($, 1)))];
+    		char data[while(std::mem::read_string($-1, 1) != "$")];
+    	}
+    	else {
+    		char code[while(std::mem::read_unsigned($, 1) != 0x00)];
+    	}
+    }
+};
+
+struct FileHeader {
+	DOSHeader dosHeader;
+	DOSStub dosStub @ dosHeader.headerSizeInParagraphs * 16;
+};
+
+FileHeader fileHeader @ 0x00;
+
+enum DGroupType : u8 {
+	NoAutoData,
+	SingleData,
+	MultipleData,
+	Null
+};
+
+fn formatDGroupType(u8 value) {
+	DGroupType dgroup = value;
+	
+	return dgroup;
+};
+
+enum AppType : u8 {
+	None,
+	Fullscreen,
+	WinPMCompatible,
+	UsesWinPM
+};
+
+fn formatAppType(u8 value) {
+	AppType app = value;
+	
+	return app;
+};
+
+bitfield ProgramFlags {
+	dGroupType : 2 [[format("formatDGroupType")]];
+	globalInitialization : 1;
+	protectedModeOnly : 1;
+	instructions86 : 1;
+	instructions286 : 1;
+	instructions386 : 1;
+	instructionsX87 : 1;
+};
+
+bitfield ApplicationFlags {
+	applicationType : 2 [[format("formatAppType")]];
+	padding : 1;
+	os2Application : 1;
+	reserved : 1;
+	imageError : 1;
+	nonConforming : 1;
+	dll : 1;
+};
+
+enum OSType : u8 {
+	Unknown = 0x00,
+	OS2 = 0x01,
+	Win16 = 0x02,
+	DOS4 = 0x03,
+	Win32 = 0x04,
+	BorlandOSServices = 0x05,
+	PharlapDOSExtenderOS2 = 0x81,
+	PharlapDOSExtenderWindows = 0x82
+};
+
+bitfield OS2EXEFlags {
+	longFilename : 1;
+	protectedMode : 1;
+	proportionalFonts : 1;
+	gangloadArea : 1;
+};
+
+struct NEHeader { 
+    char signature[2];
+    u8 majorLinkerVersion;
+    u8 minorLinkerVersion;
+    u16 entryTableOffset;
+    u16 entryTableLength;
+    u32 fileCRC;
+    ProgramFlags programFlags;
+    ApplicationFlags appFlags;
+    u16 autoDataSegmentIndex;
+    u16 initHeapSize;
+    u16 initStackSize;
+    u32 entryPoint;
+    u32 initialStackPointer;
+    u16 segmentCount;
+    u16 moduleReferenceCount;
+    u16 nonResidentNamesTableSize;
+    u16 segmentTableOffset;
+    u16 resourceTableOffset;
+    u16 residentNamesTableOffset;
+    u16 moduleReferenceTableOffset;
+    u16 importedNamesTableOffset;
+    u8 *nonResidentNamesTablePointer[nonResidentNamesTableSize] : u32;
+    u16 moveableEntryCount;
+    u16 fileAlignmentSizeShiftCount;
+    u16 resourceCount;
+    OSType targetOS;
+    OS2EXEFlags os2ExeFlags;
+    u16 thunksReturnOffset;
+    u16 segmentReferenceThunksOffset;
+    u16 minimumCodeSwapAreaSize;
+    u8 expectedMinorWindowsVersion;
+    u8 expectedMajorWindowsVersion;
+};
+
+NEHeader neHeader @ fileHeader.dosHeader.neHeaderPointer;
+
+bitfield SegmentTableFlags {
+	dataSegment : 1;
+	typeMask : 2;
+	padding : 1;
+	moveable : 1;
+	padding : 1;
+	preloaded : 1;
+	padding : 1;
+	containsRelocationInfo : 1;
+	padding : 1;
+	discardPriority : 4;
+} [[right_to_left]];
+
+struct SegmentTable {
+	u16 segmentDataPointer;
+	u16 segmentLength;
+	SegmentTableFlags segmentTableFlags;
+	u16 minimumAllocationSize;
+};
+
+SegmentTable segmentTable[neHeader.segmentCount] @ addressof(neHeader) + neHeader.segmentTableOffset;
+
+bitfield BlockFlags {
+	padding : 4;
+	moveable : 1;
+	shared : 1;
+	preload : 1;
+	padding : 9;
+};
+
+struct ResourceTypeInformationBlock {
+	u8 *resourcePointer : u16;
+	u16 resourceLength;
+	BlockFlags flags;
+	u16 resourceID;
+	u32 reserved;
+};
+
+struct ResourceRecord {
+	u16 typeID;
+	u16 numberOfResources;
+	u32 reserved;
+	ResourceTypeInformationBlock blocks[numberOfResources];
+};
+
+struct ResourceTable {
+	u16 alignmentShiftCount;
+	ResourceRecord records[neHeader.resourceTableEntryCount];
+	u8 stringLength;
+	char string[stringLength];
+};
+
+ResourceTable resourceTable[neHeader.resourceCount] @ addressof(neHeader) + neHeader.resourceTableOffset;
+
+struct ResidentName {
+	u8 stringLength;
+	char string[stringLength];
+	u16 ordinalNumber;
+};
+
+ResidentName residentNameTable[while($+1 < addressof(neHeader) + neHeader.moduleReferenceTableOffset)] @ addressof(neHeader) + neHeader.residentNamesTableOffset;
+
+struct ModuleReference {
+	u16 moduleNameOffset;
+};
+
+ModuleReference moduleReferenceTable[neHeader.moduleReferenceCount] @ addressof(neHeader) + neHeader.moduleReferenceTableOffset;
+
+struct ImportedNameTable {
+	u8 stringLength;
+	char string[stringLength];
+};
+
+ImportedNameTable importedNameTable[while($ < addressof(neHeader) + neHeader.entryTableOffset)] @ addressof(neHeader) + neHeader.importedNamesTableOffset;
+
+enum EntryDataType : u8 {
+	Unused,
+	Fixed = 0x01 ... 0xFE,
+	Moveable
+};
+
+struct EntryTable {
+	u8 entryCount;
+	EntryDataType segmentIndicator;
+};
+
+EntryTable entryTable[neHeader.entryTableLength/2] @ addressof(neHeader) + neHeader.entryTableOffset;