This commit is contained in:
Guus Waals 2025-05-30 14:53:24 +08:00
parent f1b346fb0e
commit 1e91d93470
1 changed files with 114 additions and 108 deletions

View File

@ -4,6 +4,7 @@
import ghidra.app.script.GhidraScript;
import ghidra.program.model.listing.*;
import ghidra.program.model.mem.MemoryBlock;
import ghidra.program.model.address.*;
import ghidra.program.model.scalar.Scalar;
import ghidra.program.model.symbol.Reference;
@ -55,6 +56,11 @@ public class FindRelocations extends GhidraScript {
Instruction instruction = instructions.next();
analyzeInstruction(instruction);
// Check if we've gone past the end address
if (instruction.getAddress().getOffset() >= 0x00844190) {
break;
}
processedInstructions++;
if (processedInstructions % 1000 == 0) {
monitor.setProgress(processedInstructions);
@ -84,89 +90,101 @@ public class FindRelocations extends GhidraScript {
// Check for instructions that commonly use absolute addresses
if (isRelocatableInstruction(mnemonic)) {
// Check operands for absolute addresses
for (int i = 0; i < instruction.getNumOperands(); i++) {
analyzeOperand(instruction, i);
}
// Check references from this instruction - but filter out relative references
// Check references from this instruction
Reference[] refs = instruction.getReferencesFrom();
for (Reference ref : refs) {
// Skip relative references (jumps/calls with relative addressing)
if (ref.getReferenceType().isCall() || ref.getReferenceType().isJump()) {
// For jumps and calls, check if it's using absolute addressing
if (usesAbsoluteAddressing(instruction, ref)) {
Address toAddr = ref.getToAddress();
if (isInMainMemorySpace(toAddr)) {
recordRelocation(instruction.getAddress(), toAddr, mnemonic, "absolute_reference");
}
}
} else if (ref.getReferenceType().isData()) {
// Data references are more likely to be absolute
Address toAddr = ref.getToAddress();
if (isInMainMemorySpace(toAddr)) {
recordRelocation(instruction.getAddress(), toAddr, mnemonic, "data_reference");
Address toAddr = ref.getToAddress();
if (isInMainMemorySpace(toAddr)) {
// Check if the target address appears in the instruction bytes (absolute addressing)
if (containsAbsoluteAddress(instruction, toAddr)) {
recordRelocation(instruction.getAddress(), toAddr, mnemonic, "absolute_" + ref.getReferenceType().getName());
}
}
}
}
}
private boolean containsAbsoluteAddress(Instruction instruction, Address targetAddr) {
try {
byte[] instructionBytes = instruction.getBytes();
long targetValue = targetAddr.getOffset();
// Convert target address to little-endian byte array (x86 32-bit)
byte[] targetBytes = new byte[4];
targetBytes[0] = (byte) (targetValue & 0xFF);
targetBytes[1] = (byte) ((targetValue >> 8) & 0xFF);
targetBytes[2] = (byte) ((targetValue >> 16) & 0xFF);
targetBytes[3] = (byte) ((targetValue >> 24) & 0xFF);
// Search for the target address bytes in the instruction
return containsSequence(instructionBytes, targetBytes);
} catch (Exception e) {
return false;
}
}
private boolean containsSequence(byte[] haystack, byte[] needle) {
if (needle.length > haystack.length) {
return false;
}
for (int i = 0; i <= haystack.length - needle.length; i++) {
boolean found = true;
for (int j = 0; j < needle.length; j++) {
if (haystack[i + j] != needle[j]) {
found = false;
break;
}
}
if (found) {
return true;
}
}
return false;
}
private boolean isRelocatableInstruction(String mnemonic) {
// Instructions that commonly use absolute addresses
return mnemonic.equals("mov") || mnemonic.equals("lea") ||
mnemonic.equals("call") || mnemonic.equals("jmp") ||
mnemonic.equals("push") || mnemonic.equals("cmp") ||
mnemonic.equals("test") || mnemonic.equals("add") ||
mnemonic.equals("sub") || mnemonic.equals("and") ||
mnemonic.equals("or") || mnemonic.equals("xor") ||
mnemonic.startsWith("j"); // conditional jumps
}
private void analyzeOperand(Instruction instruction, int opIndex) {
Object[] operandObjects = instruction.getOpObjects(opIndex);
for (Object obj : operandObjects) {
if (obj instanceof Address) {
Address addr = (Address) obj;
if (isInMainMemorySpace(addr)) {
recordRelocation(instruction.getAddress(), addr,
instruction.getMnemonicString(), "operand_" + opIndex);
}
} else if (obj instanceof Scalar) {
Scalar scalar = (Scalar) obj;
// Check if scalar value looks like an address in our memory space
long value = scalar.getUnsignedValue();
if (looksLikeAddress(value)) {
try {
Address addr = currentProgram.getAddressFactory().getDefaultAddressSpace().getAddress(value);
if (isInMainMemorySpace(addr)) {
recordRelocation(instruction.getAddress(), addr,
instruction.getMnemonicString(), "scalar_" + opIndex);
}
} catch (Exception e) {
// Invalid address, ignore
}
}
}
}
mnemonic.equals("call") || mnemonic.equals("jmp") ||
mnemonic.equals("push") || mnemonic.equals("cmp") ||
mnemonic.equals("test") || mnemonic.equals("add") ||
mnemonic.equals("sub") || mnemonic.equals("and") ||
mnemonic.equals("or") || mnemonic.equals("xor") ||
mnemonic.startsWith("j"); // All jumps, we'll filter by byte analysis
}
private void analyzeDataReferences(long instructionsProcessed, long totalWork) {
// Check data sections for absolute addresses
AddressSetView dataAddresses = currentProgram.getMemory().getLoadedAndInitializedAddressSet();
long totalDataBytes = dataAddresses.getNumAddresses();
// Only scan actual data sections, not code sections
MemoryBlock[] blocks = currentProgram.getMemory().getBlocks();
long processedBytes = 0;
int pointerSize = currentProgram.getDefaultPointerSize();
for (AddressRange range : dataAddresses) {
for (MemoryBlock block : blocks) {
// Skip executable blocks (code sections)
if (block.isExecute()) {
continue;
}
// Only scan initialized data blocks
if (!block.isInitialized()) {
continue;
}
if (monitor.isCancelled()) {
println("Operation cancelled by user");
return;
}
Address addr = range.getMinAddress();
while (addr != null && addr.compareTo(range.getMaxAddress()) <= 0) {
if (block.getName() == ".rsrc") {
continue;
}
println("Scanning data block: " + block.getName() + " (" + block.getStart() + " - " + block.getEnd() + ")");
Address addr = block.getStart();
while (addr != null && addr.compareTo(block.getEnd()) <= 0) {
try {
// Check if this location contains a pointer-sized value
byte[] bytes = new byte[pointerSize];
@ -188,16 +206,9 @@ public class FindRelocations extends GhidraScript {
}
}
addr = addr.add(pointerSize); // Jump by pointer size for efficiency
addr = addr.add(pointerSize);
processedBytes += pointerSize;
// Update progress every 10000 bytes
if (processedBytes % 10000 == 0) {
long currentProgress = instructionsProcessed + (processedBytes / pointerSize);
monitor.setProgress(currentProgress);
monitor.setMessage("Analyzing data: " + (processedBytes * 100 / totalDataBytes) + "% complete");
}
} catch (Exception e) {
addr = addr.add(1);
processedBytes++;
@ -222,31 +233,6 @@ public class FindRelocations extends GhidraScript {
&& value <= addrMax; // Typical executable range
}
private boolean usesAbsoluteAddressing(Instruction instruction, Reference ref) {
// Check the instruction bytes to determine addressing mode
String mnemonic = instruction.getMnemonicString().toLowerCase();
// For x86, most conditional jumps (JA, JE, JNE, etc.) use relative addressing
if (mnemonic.startsWith("j") && !mnemonic.equals("jmp")) {
return false; // Conditional jumps are typically relative
}
// For JMP and CALL, check the operand representation
for (int i = 0; i < instruction.getNumOperands(); i++) {
String operandStr = instruction.getDefaultOperandRepresentation(i);
// If operand shows as a direct address (not offset), it might be absolute
// But we need to be more sophisticated here...
// Check if this is an indirect reference [address] which would be absolute
if (operandStr.contains("[") && operandStr.contains("]")) {
return true; // Indirect addressing typically uses absolute addresses
}
}
// For now, assume most jumps/calls are relative unless proven otherwise
return false;
}
private void recordRelocation(Address fromAddr, Address toAddr, String instruction, String type) {
if (foundRelocations.add(toAddr)) {
String instructionBytes = getInstructionBytesString(fromAddr);
@ -274,23 +260,43 @@ public class FindRelocations extends GhidraScript {
sb.append(String.format("%02x", bytes[i] & 0xFF));
}
return sb.toString();
} else {
// This is a data reference, show the pointer bytes
byte[] bytes = new byte[4]; // Show 4 bytes for data
int bytesRead = currentProgram.getMemory().getBytes(addr, bytes);
if (bytesRead > 0) {
StringBuilder sb = new StringBuilder();
for (int i = 0; i < bytesRead; i++) {
if (i > 0) sb.append(" ");
sb.append(String.format("%02x", bytes[i] & 0xFF));
}
return sb.toString();
}
}
} catch (Exception e) {
// If it's a data reference, try to get the bytes at that location
try {
byte[] bytes = new byte[4]; // Show 4 bytes for data
currentProgram.getMemory().getBytes(addr, bytes);
StringBuilder sb = new StringBuilder();
for (int i = 0; i < bytes.length; i++) {
if (i > 0)
sb.append(" ");
sb.append(String.format("%02x", bytes[i] & 0xFF));
}
return sb.toString();
} catch (Exception ex) {
return "??";
// Check if this is in an initialized memory block
if (currentProgram.getMemory().contains(addr)) {
return "unreadable";
}
}
return "??";
}
private boolean isPartOfFunction(Address addr) {
// Check if there's an instruction at this address
Instruction instruction = currentProgram.getListing().getInstructionAt(addr);
if (instruction != null) {
return true;
}
// Check if this address is within any function's body
Function function = currentProgram.getFunctionManager().getFunctionContaining(addr);
if (function != null) {
// Additional check: make sure we're in the function body, not just data referenced by it
AddressSetView functionBody = function.getBody();
return functionBody.contains(addr);
}
return false;
}
}