Addes support to load unbound LEs

yetmorecode · Apr 18, 2022 · b164bbe · b164bbe
1 parent 2dd83ff
commit b164bbe
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Showing 3 changed files with 62 additions and 55 deletions.
diff --git a/extension.properties b/extension.properties
@@ -1,4 +1,4 @@
-name=LXLoader
+name=@extname@
 description=Linear Executable (LX/LE/LC) loader with various customization options
 author=https://github.com/yetmorecode
 createdOn=2021-12-13

diff --git a/src/main/java/yetmorecode/ghidra/LxLoader.java b/src/main/java/yetmorecode/ghidra/LxLoader.java
@@ -89,6 +89,7 @@ public Collection<LoadSpec> findSupportedLoadSpecs(ByteProvider provider) throws
 			e.printStackTrace();
 		} catch (InvalidHeaderException e) {
 			// Everything is ok, but the provided data is not a valid LX/LE/LC
+			System.out.println("foobar");
 		}
 		return loadSpecs;
 	}
@@ -379,7 +380,7 @@ private byte[] createObjectBlock(Program program, LxExecutable le, ObjectTableEn
 						fixupsHandled++;
 					} else {
 						Msg.warn(this, String.format(
-							"WARNING: unhandled fixup #%x_%s at %08x (type %02x, page %03x): %s -> object#%x:%x",
+							"WARNING: unhandled fixup #%x_%s at %08x (type %02x): %s -> object#%x:%x",
 							f.index, f.shortname(),  f.getSourceAddress(),
 							index,
 							f.hasSourceList() ? "source list " + f.sourceCount : String.format("%x", f.sourceOffset),

diff --git a/src/main/java/yetmorecode/ghidra/format/lx/model/LxExecutable.java b/src/main/java/yetmorecode/ghidra/format/lx/model/LxExecutable.java
@@ -23,55 +23,61 @@ public class LxExecutable extends yetmorecode.file.format.lx.LxExecutable {
 
 	public LxExecutable(GenericFactory factory, ByteProvider bp, LoaderOptions options) throws IOException, InvalidHeaderException {
     	reader = new FactoryBundledWithBinaryReader(factory, bp, true);
-    	// Try reading MZ header
-        mzHeader = DOSHeader.createDOSHeader(reader);
-
-        if (mzHeader.isDosSignature()) {
-        	// Try reading LX header
-        	header = new LxHeader(reader, (short) mzHeader.e_lfanew());
-
-        	// Read object table
-        	int objectTableOffset = mzHeader.e_lfanew() + header.objectTableOffset;
-        	for (int i = 0; i < header.objectCount; i++) {
-        		var offset = objectTableOffset + i * yetmorecode.file.format.lx.ObjectTableEntry.SIZE;
-        		ObjectTableEntry e = new ObjectTableEntry(reader, offset);
-        		e.number = i+1;
-        		objects.add(e);
-        	}
-
-        	// Read fixup page table
-        	fixupPageTable = new int[header.pageCount+1];
-        	var tableOffset = getDosHeader().e_lfanew() + header.fixupPageTableOffset;
-        	for (int i = 0; i <= header.pageCount; i++) {
-        		fixupPageTable[i] = getReader().readInt(tableOffset + i * 4);
-        	}
-
-        	// Read fixups
-        	var fixupRecordOffset = getDosHeader().e_lfanew() + header.fixupRecordTableOffset;
-        	fixupCount = 0;
-        	//for (int i = 1; i <= header.pageCount; i++) {
-        	for (var object : objects) {
-        		for (var i = 0; i < object.pageCount; i++) {
-        			var page = object.pageTableIndex + i;
-	        		fixups.put(page, new ArrayList<>());
-	        		var fixupBegin = getFixupBegin(page);
-	        		var fixupEnd = getFixupEnd(page);
-	        		var fixupDataSize = fixupEnd - fixupBegin;
-	        		var current = 0;
-	    			while (current < fixupDataSize) {
-	    				var fixup = new FixupRecord(
-    						reader, 
-    						fixupRecordOffset + fixupBegin + current, 
-    						++fixupCount, 
-    						options.getBaseAddress(object),
-    						i
-	    				);
-	    				fixups.get(page).add(fixup);
-	    				current += fixup.size;
-	    			}
-        		}
-        	}
-        }
+    	var lfanew = 0;
+    	try {
+	    	// Try reading MZ header
+	        mzHeader = DOSHeader.createDOSHeader(reader);
+	        if (mzHeader.isDosSignature()) {
+	        	lfanew = mzHeader.e_lfanew();
+	        }
+    	} catch (Exception e) {
+
+    	}
+
+    	// Try reading LX header
+    	header = new LxHeader(reader, (short) lfanew);
+
+    	// Read object table
+    	int objectTableOffset = lfanew + header.objectTableOffset;
+    	for (int i = 0; i < header.objectCount; i++) {
+    		var offset = objectTableOffset + i * yetmorecode.file.format.lx.ObjectTableEntry.SIZE;
+    		ObjectTableEntry e = new ObjectTableEntry(reader, offset);
+    		e.number = i+1;
+    		objects.add(e);
+    	}
+
+    	// Read fixup page table
+    	fixupPageTable = new int[header.pageCount+1];
+    	var tableOffset = lfanew + header.fixupPageTableOffset;
+    	for (int i = 0; i <= header.pageCount; i++) {
+    		fixupPageTable[i] = getReader().readInt(tableOffset + i * 4);
+    	}
+
+    	// Read fixups
+    	var fixupRecordOffset = lfanew + header.fixupRecordTableOffset;
+    	fixupCount = 0;
+    	//for (int i = 1; i <= header.pageCount; i++) {
+    	for (var object : objects) {
+    		for (var i = 0; i < object.pageCount; i++) {
+    			var page = object.pageTableIndex + i;
+        		fixups.put(page, new ArrayList<>());
+        		var fixupBegin = getFixupBegin(page);
+        		var fixupEnd = getFixupEnd(page);
+        		var fixupDataSize = fixupEnd - fixupBegin;
+        		var current = 0;
+    			while (current < fixupDataSize) {
+    				var fixup = new FixupRecord(
+						reader, 
+						fixupRecordOffset + fixupBegin + current, 
+						++fixupCount, 
+						options.getBaseAddress(object),
+						i
+    				);
+    				fixups.get(page).add(fixup);
+    				current += fixup.size;
+    			}
+    		}
+    	}
     }
 
 	public static void checkProvider(GenericFactory factory, ByteProvider provider) throws InvalidHeaderException, IOException {
@@ -82,12 +88,12 @@ public static void checkProvider(GenericFactory factory, ByteProvider provider)
 
     	// Try parsing MZ header
         var mzHeader = DOSHeader.createDOSHeader(reader);
-        if (!mzHeader.isDosSignature()) {
-        	throw new InvalidHeaderException("No MS-DOS header found (invalid signature)"); 
+        var lfanew = 0;
+        if (mzHeader.isDosSignature()) {
+        	 lfanew = mzHeader.e_lfanew();
         }
-
         // Try parsing LX Header
-    	new LxHeader(reader, (short) mzHeader.e_lfanew());
+    	new LxHeader(reader, (short) lfanew);
 	}
 
     /**