Emulator - added simplified program emulation API via EmulatorHelper

This commit is contained in:
ghidra1 2019-05-17 19:01:55 -04:00
parent 8843a70947
commit 7c5523362c
23 changed files with 3112 additions and 27 deletions

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/* ###
* IP: GHIDRA
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
// An example script demonstrating the ability to emulate a specific portion of code within
// a disassembled program to extract return values of interest (deobfuscated data in this case)
// and generate program listing comments.
// This script emulates the "main" function within the deobExample program
// (see docs/GhidraClass/ExerciseFiles/Emulation/Source) built with gcc for x86-64.
// The program's "data" array contains simple obfuscated data and has a function "deobfuscate"
// which is called for each piece of obfuscated data. The "main" function loops through all
// the data and deobfuscates each one invoking the "use_string" function for each deobfuscated
// data. Breakpoints are placed on the call (and just after the call)
// to the function "deobfuscate" so that the various return values can be recorded with a comment
// placed just after the call.
//@category Examples.Emulation
import ghidra.app.emulator.EmulatorHelper;
import ghidra.app.script.GhidraScript;
import ghidra.app.util.opinion.ElfLoader;
import ghidra.pcode.emulate.EmulateExecutionState;
import ghidra.program.model.address.Address;
import ghidra.program.model.listing.Instruction;
import ghidra.program.model.listing.Program;
import ghidra.program.model.symbol.*;
import ghidra.util.Msg;
import ghidra.util.exception.NotFoundException;
public class EmuX86DeobfuscateExampleScript extends GhidraScript {
private static String PROGRAM_NAME = "deobExample";
private EmulatorHelper emuHelper;
// Important breakpoint locations
private Address deobfuscateCall;
private Address deobfuscateReturn;
// Function locations
private Address mainFunctionEntry; // start of emulation address
// Address used as final return location
// A breakpoint will be set here so we can determine when function execution
// has completed.
private static final long CONTROLLED_RETURN_OFFSET = 0;
private Address controlledReturnAddr; // end of emulation address
// First argument passed to deobfuscate function on last call (used for comment generation)
private long lastDeobfuscateArg0;
@Override
protected void run() throws Exception {
String format =
currentProgram.getOptions(Program.PROGRAM_INFO).getString("Executable Format", null);
if (currentProgram == null || !currentProgram.getName().startsWith(PROGRAM_NAME) ||
!"x86:LE:64:default".equals(currentProgram.getLanguageID().toString()) ||
!ElfLoader.ELF_NAME.equals(format)) {
printerr(
"This emulation example script is specifically intended to be executed against the\n" +
PROGRAM_NAME +
" program whose source is contained within the GhidraClass exercise files\n" +
"(see docs/GhidraClass/ExerciseFiles/Emulation/" + PROGRAM_NAME + ".c).\n" +
"This program should be compiled using gcc for x86 64-bit, imported into your project, \n" +
"analyzed and open as the active program before running ths script.");
return;
}
// Identify function to be emulated
mainFunctionEntry = getSymbolAddress("main");
// Obtain entry instruction in order to establish initial processor context
Instruction entryInstr = getInstructionAt(mainFunctionEntry);
if (entryInstr == null) {
printerr("Instruction not found at main entry point: " + mainFunctionEntry);
return;
}
// Identify important symbol addresses
// NOTE: If the sample is recompiled the following addresses may need to be adjusted
Instruction callSite = getCalledFromInstruction("deobfuscate");
if (callSite == null) {
printerr("Instruction not found at call site for: deobfuscate");
return;
}
deobfuscateCall = callSite.getAddress();
deobfuscateReturn = callSite.getFallThrough(); // instruction address immediately after deobfuscate call
// Remove prior pre-comment
setPreComment(deobfuscateReturn, null);
// Establish emulation helper
emuHelper = new EmulatorHelper(currentProgram);
try {
// Initialize stack pointer (not used by this example)
long stackOffset =
(entryInstr.getAddress().getAddressSpace().getMaxAddress().getOffset() >>> 1) -
0x7fff;
emuHelper.writeRegister(emuHelper.getStackPointerRegister(), stackOffset);
// Setup breakpoints
emuHelper.setBreakpoint(deobfuscateCall);
emuHelper.setBreakpoint(deobfuscateReturn);
// Set controlled return location so we can identify return from emulated function
controlledReturnAddr = getAddress(CONTROLLED_RETURN_OFFSET);
emuHelper.writeStackValue(0, 8, CONTROLLED_RETURN_OFFSET);
emuHelper.setBreakpoint(controlledReturnAddr);
Msg.debug(this, "EMU starting at " + mainFunctionEntry);
// Execution loop until return from function or error occurs
while (!monitor.isCancelled()) {
boolean success =
(emuHelper.getEmulateExecutionState() == EmulateExecutionState.BREAKPOINT)
? emuHelper.run(monitor)
: emuHelper.run(mainFunctionEntry, entryInstr, monitor);
Address executionAddress = emuHelper.getExecutionAddress();
if (monitor.isCancelled()) {
println("Emulation cancelled");
return;
}
if (executionAddress.equals(controlledReturnAddr)) {
println("Returned from function");
return;
}
if (!success) {
String lastError = emuHelper.getLastError();
printerr("Emulation Error: " + lastError);
return;
}
processBreakpoint(executionAddress);
}
}
finally {
// cleanup resources and release hold on currentProgram
emuHelper.dispose();
}
}
private Address getAddress(long offset) {
return currentProgram.getAddressFactory().getDefaultAddressSpace().getAddress(offset);
}
/**
* Perform processing for the various breakpoints.
* @param addr current execute address where emulation has been suspended
* @throws Exception if an error occurs
*/
private void processBreakpoint(Address addr) throws Exception {
if (addr.equals(deobfuscateCall)) {
lastDeobfuscateArg0 = emuHelper.readRegister("RDI").longValue();
}
else if (addr.equals(deobfuscateReturn)) {
long deobfuscateReturnValue = emuHelper.readRegister("RAX").longValue();
String str = "deobfuscate(src=0x" + Long.toHexString(lastDeobfuscateArg0) + ") -> \"" +
emuHelper.readNullTerminatedString(getAddress(deobfuscateReturnValue), 32) + "\"";
String comment = getPreComment(deobfuscateReturn);
if (comment == null) {
comment = "";
}
else {
comment += "\n";
}
comment += str;
println("Updated pre-comment at " + deobfuscateReturn);
setPreComment(deobfuscateReturn, comment);
}
}
private Instruction getCalledFromInstruction(String functionName) {
Symbol s = SymbolUtilities.getExpectedLabelOrFunctionSymbol(currentProgram, functionName,
m -> printerr(m));
for (Reference ref : s.getReferences(monitor)) {
if (ref.getReferenceType().isCall()) {
return currentProgram.getListing().getInstructionAt(ref.getFromAddress());
}
}
return null;
}
private Address getSymbolAddress(String symbolName) throws NotFoundException {
Symbol symbol = SymbolUtilities.getLabelOrFunctionSymbol(currentProgram, symbolName,
err -> Msg.error(this, err));
if (symbol != null) {
return symbol.getAddress();
}
throw new NotFoundException("Failed to locate label: " + symbolName);
}
}

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/* ###
* IP: GHIDRA
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
// An example script demonstrating the ability to emulate a specific portion of code within
// a disassembled program to dump data of interest (deobfuscated data in this case).
// This script emulates the "main" function within the deobHookExampleX86 program
// (see docs/GhidraClass/ExerciseFiles/Emulation/Source) built with gcc for x86-64.
// The program's "data" array contains simple obfuscated data and has a function "deobfuscate"
// which is called for each piece of ofuscated data. The "main" function loops through all
// the data and deobfuscates each one invoking the "use_string" function for each deobfuscated
// data. This script hooks the functions "malloc", "free" and "use_string" where the later
// simply prints the deobfuscated string passed as an argument.
//@category Examples.Emulation
import java.util.HashMap;
import java.util.Map;
import ghidra.app.emulator.EmulatorHelper;
import ghidra.app.script.GhidraScript;
import ghidra.app.util.opinion.ElfLoader;
import ghidra.pcode.emulate.EmulateExecutionState;
import ghidra.program.model.address.*;
import ghidra.program.model.lang.InsufficientBytesException;
import ghidra.program.model.listing.Function;
import ghidra.program.model.listing.Program;
import ghidra.program.model.symbol.*;
import ghidra.util.Msg;
import ghidra.util.exception.NotFoundException;
public class EmuX86GccDeobfuscateHookExampleScript extends GhidraScript {
private static String PROGRAM_NAME = "deobHookExample";
// Heap allocation area
private static final int MALLOC_REGION_SIZE = 0x1000;
// Address used as final return location
private static final long CONTROLLED_RETURN_OFFSET = 0;
private EmulatorHelper emuHelper;
private SimpleMallocMgr mallocMgr;
// Important breakpoint locations for hooking behavior not contained with binary (e.g., dynamic library)
private Address mallocEntry;
private Address freeEntry;
private Address strlenEntry;
private Address useStringEntry;
// Function locations
private Address mainFunctionEntry; // start of emulation
private Address controlledReturnAddr; // end of emulation
@Override
protected void run() throws Exception {
String format =
currentProgram.getOptions(Program.PROGRAM_INFO).getString("Executable Format", null);
if (currentProgram == null || !currentProgram.getName().startsWith(PROGRAM_NAME) ||
!"x86:LE:64:default".equals(currentProgram.getLanguageID().toString()) ||
!ElfLoader.ELF_NAME.equals(format)) {
printerr(
"This emulation example script is specifically intended to be executed against the\n" +
PROGRAM_NAME +
" program whose source is contained within the GhidraClass exercise files\n" +
"(see docs/GhidraClass/ExerciseFiles/Emulation/" + PROGRAM_NAME + ".c).\n" +
"This program should be compiled using gcc for x86 64-bit, imported into your project, \n" +
"analyzed and open as the active program before running ths script.");
return;
}
// Identify function be emulated
mainFunctionEntry = getSymbolAddress("main");
useStringEntry = getSymbolAddress("use_string");
// Identify important symbol addresses
mallocEntry = getExternalThunkAddress("malloc");
freeEntry = getExternalThunkAddress("free");
strlenEntry = getExternalThunkAddress("strlen");
// Establish emulation helper
emuHelper = new EmulatorHelper(currentProgram);
try {
// Initialize stack pointer (not used by this example)
long stackOffset =
(mainFunctionEntry.getAddressSpace().getMaxAddress().getOffset() >>> 1) - 0x7fff;
emuHelper.writeRegister(emuHelper.getStackPointerRegister(), stackOffset);
// Establish simple malloc memory manager with memory region spaced relative to stack pointer
mallocMgr = new SimpleMallocMgr(getAddress(stackOffset - 0x10000), MALLOC_REGION_SIZE);
// Setup hook breakpoints
emuHelper.setBreakpoint(mallocEntry);
emuHelper.setBreakpoint(freeEntry);
emuHelper.setBreakpoint(strlenEntry);
emuHelper.setBreakpoint(useStringEntry);
// Set controlled return location so we can identify return from emulated function
controlledReturnAddr = getAddress(CONTROLLED_RETURN_OFFSET);
emuHelper.writeStackValue(0, 8, CONTROLLED_RETURN_OFFSET);
emuHelper.setBreakpoint(controlledReturnAddr);
// This example directly manipulates the PC register to facilitate hooking
// which must alter the PC during a breakpoint, and optional stepping which does not
// permit an initial address to be specified.
emuHelper.writeRegister(emuHelper.getPCRegister(), mainFunctionEntry.getOffset());
Msg.debug(this, "EMU starting at " + emuHelper.getExecutionAddress());
// Execution loop until return from function or error occurs
while (!monitor.isCancelled()) {
// Use stepping if needed for troubleshooting - although it runs much slower
//boolean success = emuHelper.step();
boolean success = emuHelper.run(monitor);
Address executionAddress = emuHelper.getExecutionAddress();
if (monitor.isCancelled()) {
println("Emulation cancelled");
return;
}
if (executionAddress.equals(controlledReturnAddr)) {
println("Returned from function");
return;
}
if (!success) {
String lastError = emuHelper.getLastError();
printerr("Emulation Error: " + lastError);
return;
}
processBreakpoint(executionAddress);
}
}
finally {
// cleanup resources and release hold on currentProgram
emuHelper.dispose();
}
}
private Address getAddress(long offset) {
return currentProgram.getAddressFactory().getDefaultAddressSpace().getAddress(offset);
}
/**
* Perform processing for the various hook points where breakpoints have been set.
* @param addr current execute address where emulation has been suspended
* @throws Exception if an error occurs
*/
private void processBreakpoint(Address addr) throws Exception {
// malloc hook
if (addr.equals(mallocEntry)) {
int size = emuHelper.readRegister("RDI").intValue();
Address memAddr = mallocMgr.malloc(size);
emuHelper.writeRegister("RAX", memAddr.getOffset());
}
// free hook
else if (addr.equals(freeEntry)) {
Address freeAddr = getAddress(emuHelper.readRegister("RDI").longValue());
mallocMgr.free(freeAddr);
}
// strlen hook
else if (addr.equals(strlenEntry)) {
Address ptr = getAddress(emuHelper.readRegister("RDI").longValue());
int len = 0;
while (emuHelper.readMemoryByte(ptr) != 0) {
++len;
ptr = ptr.next();
}
emuHelper.writeRegister("RAX", len);
}
// use_string hook - print string
else if (addr.equals(useStringEntry)) {
Address stringAddr = getAddress(emuHelper.readRegister("RDI").longValue());
String str = emuHelper.readNullTerminatedString(stringAddr, 32);
println("use_string: " + str); // output string argument to consoles
}
// unexpected
else {
if (emuHelper.getEmulateExecutionState() != EmulateExecutionState.BREAKPOINT) {
// assume we are stepping and simply return
return;
}
throw new NotFoundException("Unhandled breakpoint at " + addr);
}
// force early return
long returnOffset = emuHelper.readStackValue(0, 8, false).longValue();
emuHelper.writeRegister(emuHelper.getPCRegister(), returnOffset);
}
/**
* Get the thunk function corresponding to an external function. Such thunks
* should reside within the EXTERNAL block. (Note: this is specific to the ELF import)
* @param symbolName external function name
* @return address of thunk function which corresponds to an external function
* @throws NotFoundException if thunk not found
*/
private Address getExternalThunkAddress(String symbolName) throws NotFoundException {
Symbol externalSymbol = currentProgram.getSymbolTable().getExternalSymbol(symbolName);
if (externalSymbol != null && externalSymbol.getSymbolType() == SymbolType.FUNCTION) {
Function f = (Function) externalSymbol.getObject();
Address[] thunkAddrs = f.getFunctionThunkAddresses();
if (thunkAddrs.length == 1) {
return thunkAddrs[0];
}
}
throw new NotFoundException("Failed to locate label: " + symbolName);
}
/**
* Get the global namespace symbol address which corresponds to the specified name.
* @param symbolName global symbol name
* @return symbol address
* @throws NotFoundException if symbol not found
*/
private Address getSymbolAddress(String symbolName) throws NotFoundException {
Symbol symbol = SymbolUtilities.getLabelOrFunctionSymbol(currentProgram, symbolName,
err -> Msg.error(this, err));
if (symbol != null) {
return symbol.getAddress();
}
throw new NotFoundException("Failed to locate label: " + symbolName);
}
/**
* <code>SimpleMallocMgr</code> provides a simple malloc memory manager to be used by the
* malloc/free hooked implementations.
*/
private class SimpleMallocMgr {
private AddressSet allocSet;
private Map<Address, AddressRange> mallocMap = new HashMap<>();
/**
* <code>SimpleMallocMgr</code> constructor.
* @param rangeStart start of the free malloc region (i.e., Heap) which has been
* deemed a safe
* @param byteSize
* @throws AddressOverflowException
*/
SimpleMallocMgr(Address rangeStart, int byteSize) throws AddressOverflowException {
allocSet = new AddressSet(
new AddressRangeImpl(rangeStart, rangeStart.addNoWrap(byteSize - 1)));
}
synchronized Address malloc(int byteLength) throws InsufficientBytesException {
if (byteLength <= 0) {
throw new IllegalArgumentException("malloc request for " + byteLength);
}
for (AddressRange range : allocSet.getAddressRanges()) {
if (range.getLength() >= byteLength) {
AddressRange mallocRange = new AddressRangeImpl(range.getMinAddress(),
range.getMinAddress().add(byteLength - 1));
mallocMap.put(mallocRange.getMinAddress(), mallocRange);
allocSet.delete(mallocRange);
return mallocRange.getMinAddress();
}
}
throw new InsufficientBytesException(
"SimpleMallocMgr failed to allocate " + byteLength + " bytes");
}
synchronized void free(Address mallocRangeAddr) {
AddressRange range = mallocMap.remove(mallocRangeAddr);
if (range == null) {
throw new IllegalArgumentException(
"free request for unallocated block at " + mallocRangeAddr);
}
allocSet.add(range);
}
}
}

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/* ###
* IP: GHIDRA
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package ghidra.app.emulator;
import java.util.*;
import ghidra.app.emulator.memory.*;
import ghidra.app.emulator.state.*;
import ghidra.app.plugin.processors.sleigh.SleighLanguage;
import ghidra.pcode.emulate.*;
import ghidra.pcode.error.LowlevelError;
import ghidra.pcode.memstate.*;
import ghidra.program.disassemble.Disassembler;
import ghidra.program.model.address.*;
import ghidra.program.model.lang.*;
import ghidra.program.model.listing.Instruction;
import ghidra.util.*;
import ghidra.util.exception.CancelledException;
import ghidra.util.task.TaskMonitor;
import ghidra.util.task.TaskMonitorAdapter;
public class Emulator {
private final MemoryFaultHandler faultHandler;
private SleighLanguage language;
private AddressFactory addrFactory;
private CompositeLoadImage loadImage = new CompositeLoadImage();
private RegisterState mstate;
private MemoryPageBank registerState;
private FilteredMemoryState memState;
private ghidra.pcode.emulate.BreakTableCallBack breakTable;
private Emulate emulator;
private boolean emuHalt = true;
private boolean isExecuting = false;
private boolean writeBack = false;
private int pageSize;
private String pcName;
private long initialPC;
private int instExecuted = 0;
public Emulator(EmulatorConfiguration cfg) {
this.faultHandler = cfg.getMemoryFaultHandler();
pcName = cfg.getProgramCounterName();
writeBack = cfg.isWriteBackEnabled();
pageSize = cfg.getPreferredMemoryPageSize();
Language lang = cfg.getLanguage();
if (!(lang instanceof SleighLanguage)) {
throw new IllegalArgumentException("Invalid configuartion language [" +
lang.getLanguageID() + "]: only Sleigh languages are supported by emulator");
}
// TODO: The way this is currently done, we are unable to emulate within overlay spaces
// The addrFactory should be obtained memState which is a reversal
// When a program load image is used the addrFactory should come from the program and
// not the language. Things may also get complex in terms of handling loads/stores and
// flow associated with overlays.
language = (SleighLanguage) lang;
addrFactory = lang.getAddressFactory();
EmulatorLoadData load = cfg.getLoadData();
loadImage.addProvider(load.getMemoryLoadImage(), load.getView());
mstate = load.getInitialRegisterState();
initMemState(mstate);
breakTable = new BreakTableCallBack(language);
emulator = new Emulate(language, memState, breakTable);
try {
setExecuteAddress(initialPC);
}
catch (LowlevelError lle) {
Msg.warn(this, "pc is unmappable -- no execution possible");
}
}
private int getValidPageSize(AddressSpace space) {
int ps = pageSize;
long maxOffset = space.getMaxAddress().getOffset();
if (ps > maxOffset && maxOffset > 0) {
ps = (int) maxOffset;
}
else {
ps -= (ps % space.getAddressableUnitSize());
}
if (pageSize != ps) {
Msg.warn(this, "Emulator using adjusted page size of " + ps + " bytes for " +
space.getName() + " address space");
}
return ps;
}
private void initMemState(RegisterState rstate) {
memState = new FilteredMemoryState(language);
for (AddressSpace space : addrFactory.getPhysicalSpaces()) {
if (!space.isLoadedMemorySpace()) {
continue;
}
FilteredMemoryPageOverlay ramBank = getMemoryBank(space, getValidPageSize(space));
memState.setMemoryBank(ramBank);
}
AddressSpace registerSpace = addrFactory.getRegisterSpace();
registerState = new FilteredRegisterBank(registerSpace, pageSize, rstate, language,
writeBack, faultHandler);
memState.setMemoryBank(registerState);
initRegisters(false);
}
public MemoryState cloneMemory() {
MemoryState newMemState = new FilteredMemoryState(language);
for (AddressSpace space : addrFactory.getPhysicalSpaces()) {
if (!space.isLoadedMemorySpace()) {
continue;
}
FilteredMemoryPageOverlay ramBank = getMemoryBank(space, getValidPageSize(space));
newMemState.setMemoryBank(ramBank);
}
return newMemState;
}
public FilteredMemoryPageOverlay getMemoryBank(AddressSpace space, int ps) {
MemoryImage image =
new MemoryImage(space, language.isBigEndian(), ps, loadImage, faultHandler);
return new FilteredMemoryPageOverlay(space, image, writeBack);
}
/**
* Initialize memory state using the initial register state. If restore is true,
* only those registers within the register space which have been modified will
* be reported and restored to their initial state.
* @param restore if true restore modified registers within the register space only
*/
private void initRegisters(boolean restore) {
DataConverter conv =
language.isBigEndian() ? new BigEndianDataConverter() : new LittleEndianDataConverter();
Set<String> keys = mstate.getKeys();
for (String key : keys) {
List<byte[]> vals = mstate.getVals(key);
List<Boolean> initiailizedVals = mstate.isInitialized(key);
for (int i = 0; i < vals.size(); i++) {
String useKey = "";
if (key.equals("GDTR") || key.equals("IDTR") || key.equals("LDTR")) {
if (i == 0)
useKey = key + "_Limit";
if (i == 1)
useKey = key + "_Address";
}
else if (key.equals("S.base")) {
Integer lval = conv.getInt(vals.get(i));
if (lval != 0 && i < vals.size() - 1) {
useKey = "FS_OFFSET"; // Colossal hack
memState.setValue("FS", (i + 2) * 0x8);
}
}
else {
useKey = (vals.size() > 1) ? key + i : key;
}
Register register = language.getRegister(useKey);
if (register == null) {
useKey = useKey.toUpperCase();
register = language.getRegister(useKey);
}
if (register != null) {
if (restore && !register.getAddress().isRegisterAddress()) {
continue; // only restore registers within register space
}
byte[] valBytes = vals.get(i);
boolean initializedValue = initiailizedVals.get(i);
Address regAddr = register.getAddress();
if (restore) {
byte[] curVal = new byte[valBytes.length];
memState.getChunk(curVal, regAddr.getAddressSpace(), regAddr.getOffset(),
register.getMinimumByteSize(), false);
if (Arrays.equals(curVal, valBytes)) {
continue;
}
System.out.println(
"resetRegisters : " + useKey + "=" + dumpBytesAsSingleValue(valBytes) +
"->" + dumpBytesAsSingleValue(curVal));
}
memState.setChunk(valBytes, regAddr.getAddressSpace(), regAddr.getOffset(),
register.getMinimumByteSize());
if (!initializedValue) {
memState.setInitialized(false, regAddr.getAddressSpace(),
regAddr.getOffset(), register.getMinimumByteSize());
}
if (register.isProgramCounter() ||
register.getName().equalsIgnoreCase(pcName)) {
initialPC = conv.getValue(valBytes, valBytes.length);
}
}
}
}
}
private String dumpBytesAsSingleValue(byte[] bytes) {
StringBuffer buf = new StringBuffer("0x");
if (language.isBigEndian()) {
for (int i = 0; i < bytes.length; i++) {
String byteStr = Integer.toHexString(bytes[i] & 0xff);
if (byteStr.length() == 1) {
buf.append('0');
}
buf.append(byteStr);
}
}
else {
for (int i = bytes.length - 1; i >= 0; i--) {
String byteStr = Integer.toHexString(bytes[i] & 0xff);
if (byteStr.length() == 1) {
buf.append('0');
}
buf.append(byteStr);
}
}
return buf.toString();
}
public void dispose() {
emuHalt = true;
emulator.dispose();
if (writeBack) {
initRegisters(true);
mstate.dispose();
}
loadImage.dispose();
}
public Address genAddress(String addr) {
return addrFactory.getDefaultAddressSpace().getAddress(NumericUtilities.parseHexLong(addr));
}
public long getPC() {
return memState.getValue(pcName);
}
public String getPCRegisterName() {
return pcName;
}
public MemoryState getMemState() {
return memState;
}
public FilteredMemoryState getFilteredMemState() {
return memState;
}
public void addMemoryAccessFilter(MemoryAccessFilter filter) {
filter.addFilter(this);
}
public BreakTableCallBack getBreakTable() {
return breakTable;
}
public void setExecuteAddress(long addressableWordOffset) {
AddressSpace space = addrFactory.getDefaultAddressSpace();
Address address = space.getTruncatedAddress(addressableWordOffset, true);
emulator.setExecuteAddress(address);
}
public Address getExecuteAddress() {
return emulator.getExecuteAddress();
}
public Address getLastExecuteAddress() {
return emulator.getLastExecuteAddress();
}
public Set<String> getDefaultContext() {
return mstate.getKeys();
}
public void setHalt(boolean halt) {
emuHalt = halt;
}
public boolean getHalt() {
return emuHalt;
}
public void executeInstruction(boolean stopAtBreakpoint, TaskMonitor monitor)
throws CancelledException, LowlevelError, InstructionDecodeException {
isExecuting = true;
try {
emulator.executeInstruction(stopAtBreakpoint, monitor);
instExecuted++;
}
finally {
isExecuting = false;
}
}
/**
* @return true if halted at a breakpoint
*/
public boolean isAtBreakpoint() {
return getHalt() && emulator.getExecutionState() == EmulateExecutionState.BREAKPOINT;
}
/**
* @return emulator execution state. This can be useful within a memory fault handler to
* determine if a memory read was associated with instruction parsing (i.e., PCODE_EMIT) or
* normal an actual emulated read (i.e., EXECUTE).
*/
public EmulateExecutionState getEmulateExecutionState() {
return emulator.getExecutionState();
}
/**
* @return true if emulator is busy executing an instruction
*/
public boolean isExecuting() {
return isExecuting;
}
public SleighLanguage getLanguage() {
return language;
}
/**
* Disassemble from the current execute address
* @param count number of contiguous instructions to disassemble
* @return list of instructions
*/
public List<String> disassemble(Integer count) {
if (!emuHalt || isExecuting) {
throw new IllegalStateException("disassembly not allowed while emulator is executing");
}
// TODO: This can provide bad disassembly if reliant on future context state (e.g., end of loop)
List<String> disassembly = new ArrayList<>();
EmulateDisassemblerContext disassemblerContext = emulator.getNewDisassemblerContext();
Address addr = getExecuteAddress();
EmulateMemoryStateBuffer memBuffer = new EmulateMemoryStateBuffer(memState, addr);
Disassembler disassembler = Disassembler.getDisassembler(language, addrFactory,
TaskMonitorAdapter.DUMMY_MONITOR, null);
boolean stopOnError = false;
while (count > 0 && !stopOnError) {
memBuffer.setAddress(addr);
disassemblerContext.setCurrentAddress(addr);
InstructionBlock block = disassembler.pseudoDisassembleBlock(memBuffer,
disassemblerContext.getCurrentContextRegisterValue(), count);
if (block.hasInstructionError() && count > block.getInstructionCount()) {
InstructionError instructionError = block.getInstructionConflict();
Msg.error(this,
"Target disassembler error at " + instructionError.getConflictAddress() + ": " +
instructionError.getConflictMessage());
stopOnError = true;
}
Instruction lastInstr = null;
Iterator<Instruction> iterator = block.iterator();
while (iterator.hasNext() && count != 0) {
Instruction instr = iterator.next();
disassembly.add(instr.getAddressString(false, true) + " " + instr.toString());
lastInstr = instr;
--count;
}
try {
addr = lastInstr.getAddress().addNoWrap(lastInstr.getLength());
}
catch (Exception e) {
count = 0;
}
}
return disassembly;
}
public int getTickCount() {
return instExecuted;
}
/**
* Returns the current context register value. The context value returned reflects
* its state when the previously executed instruction was
* parsed/executed. The context value returned will feed into the next
* instruction to be parsed with its non-flowing bits cleared and
* any future context state merged in.
*/
public RegisterValue getContextRegisterValue() {
return emulator.getContextRegisterValue();
}
/**
* Sets the context register value at the current execute address.
* The Emulator should not be running when this method is invoked.
* Only flowing context bits should be set, as non-flowing bits
* will be cleared prior to parsing on instruction. In addition,
* any future context state set by the pcode emitter will
* take precedence over context set using this method. This method
* is primarily intended to be used to establish the initial
* context state.
* @param regValue
*/
public void setContextRegisterValue(RegisterValue regValue) {
emulator.setContextRegisterValue(regValue);
}
/**
* Add memory load image provider
* @param provider memory load image provider
* @param view memory region which corresponds to provider
*/
public void addProvider(MemoryLoadImage provider, AddressSetView view) {
loadImage.addProvider(provider, view);
}
}

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/* ###
* IP: GHIDRA
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package ghidra.app.emulator;
import ghidra.app.emulator.memory.EmulatorLoadData;
import ghidra.pcode.memstate.MemoryFaultHandler;
import ghidra.program.model.lang.Language;
import ghidra.program.model.lang.Register;
public interface EmulatorConfiguration {
Language getLanguage();
EmulatorLoadData getLoadData();
MemoryFaultHandler getMemoryFaultHandler();
default boolean isWriteBackEnabled() {
return false;
}
default int getPreferredMemoryPageSize() {
return 0x1000;
}
default String getProgramCounterName() {
Language lang = getLanguage();
Register pcReg = lang.getProgramCounter();
if (pcReg == null) {
throw new IllegalStateException(
"Language has not defined Program Counter Register: " + lang.getLanguageID());
}
return pcReg.getName();
}
}

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/* ###
* IP: GHIDRA
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package ghidra.app.emulator;
import java.io.IOException;
import java.io.InputStream;
import java.math.BigInteger;
import ghidra.app.emulator.memory.*;
import ghidra.app.emulator.state.DumpMiscState;
import ghidra.app.emulator.state.RegisterState;
import ghidra.framework.store.LockException;
import ghidra.pcode.emulate.BreakCallBack;
import ghidra.pcode.emulate.EmulateExecutionState;
import ghidra.pcode.memstate.MemoryFaultHandler;
import ghidra.pcode.memstate.MemoryState;
import ghidra.program.model.address.*;
import ghidra.program.model.lang.*;
import ghidra.program.model.listing.*;
import ghidra.program.model.mem.MemoryBlock;
import ghidra.program.model.mem.MemoryConflictException;
import ghidra.util.*;
import ghidra.util.exception.CancelledException;
import ghidra.util.exception.DuplicateNameException;
import ghidra.util.task.TaskMonitor;
public class EmulatorHelper implements MemoryFaultHandler, EmulatorConfiguration {
private final Program program;
private final Emulator emulator;
private Register stackPtrReg;
private AddressSpace stackMemorySpace;
private String lastError;
private MemoryWriteTracker memoryWriteTracker;
private MemoryFaultHandler faultHandler;
private BreakCallBack addressBreak = new BreakCallBack() {
@Override
public boolean addressCallback(Address addr) {
emulator.setHalt(true);
return true;
}
};
public EmulatorHelper(Program program) {
this.program = program;
stackPtrReg = program.getCompilerSpec().getStackPointer();
stackMemorySpace = program.getCompilerSpec().getStackBaseSpace();
emulator = new Emulator(this);
}
public void dispose() {
emulator.dispose();
if (memoryWriteTracker != null) {
memoryWriteTracker.dispose();
memoryWriteTracker = null;
}
}
@Override
public MemoryFaultHandler getMemoryFaultHandler() {
return this;
}
@Override
public EmulatorLoadData getLoadData() {
return new EmulatorLoadData() {
@Override
public MemoryLoadImage getMemoryLoadImage() {
return new ProgramMappedLoadImage(
new ProgramMappedMemory(program, EmulatorHelper.this));
}
@Override
public RegisterState getInitialRegisterState() {
return new DumpMiscState(getLanguage());
}
};
}
@Override
public Language getLanguage() {
return program.getLanguage();
}
public Program getProgram() {
return program;
}
/**
* Get Program Counter (PC) register defined by applicable processor specification
* @return Program Counter register
*/
public Register getPCRegister() {
return program.getLanguage().getProgramCounter();
}
/**
* Get Stack Pointer register defined by applicable compiler specification
* @return Stack Pointer register
*/
public Register getStackPointerRegister() {
return stackPtrReg;
}
/**
* Provides ability to install a low-level memory fault handler.
* The handler methods should generally return 'false' to allow
* the default handler to generate the appropriate target error.
* Within the fault handler, the EmulateExecutionState can be used
* to distinguish the pcode-emit state and the actual execution state
* since an attempt to execute an instruction at an uninitialized
* memory location will cause an uninitializedRead during the PCODE_EMIT
* state.
* @param handler memory fault handler.
*/
public void setMemoryFaultHandler(MemoryFaultHandler handler) {
faultHandler = handler;
}
/**
* @return the low-level emulator execution state
*/
public EmulateExecutionState getEmulateExecutionState() {
return emulator.getEmulateExecutionState();
}
private Register getRegister(String regName) throws IllegalArgumentException {
Register reg = program.getRegister(regName);
if (reg == null) {
throw new IllegalArgumentException("Undefined register: " + regName);
}
return reg;
}
public BigInteger readRegister(Register reg) {
if (reg.isProcessorContext()) {
RegisterValue contextRegisterValue = emulator.getContextRegisterValue();
if (!reg.equals(contextRegisterValue.getRegister())) {
contextRegisterValue = contextRegisterValue.getRegisterValue(reg);
}
return contextRegisterValue.getSignedValueIgnoreMask();
}
if (reg.getName().equals(emulator.getPCRegisterName())) {
return BigInteger.valueOf(emulator.getPC());
}
return emulator.getMemState().getBigInteger(reg);
}
public BigInteger readRegister(String regName) {
Register reg = getRegister(regName);
if (reg == null) {
throw new IllegalArgumentException("Undefined register: " + regName);
}
return readRegister(reg);
}
public void writeRegister(Register reg, long value) {
writeRegister(reg, BigInteger.valueOf(value));
}
public void writeRegister(String regName, long value) {
writeRegister(regName, BigInteger.valueOf(value));
}
public void writeRegister(Register reg, BigInteger value) {
if (reg.isProcessorContext()) {
RegisterValue contextRegisterValue = new RegisterValue(reg, value);
RegisterValue existingRegisterValue = emulator.getContextRegisterValue();
if (!reg.equals(existingRegisterValue.getRegister())) {
contextRegisterValue = existingRegisterValue.combineValues(contextRegisterValue);
}
emulator.setContextRegisterValue(contextRegisterValue);
return;
}
emulator.getMemState().setValue(reg, value);
if (reg.getName().equals(emulator.getPCRegisterName())) {
emulator.setExecuteAddress(value.longValue());
}
}
public void writeRegister(String regName, BigInteger value) {
Register reg = getRegister(regName);
if (reg == null) {
throw new IllegalArgumentException("Undefined register: " + regName);
}
writeRegister(reg, value);
}
/**
* Read string from memory state.
* @param addr memory address
* @param maxLength limit string read to this length. If return string is
* truncated, "..." will be appended.
* @return string read from memory state
*/
public String readNullTerminatedString(Address addr, int maxLength) {
int len = 0;
byte[] bytes = new byte[maxLength];
byte b = 0;
while (len < maxLength && (b = readMemoryByte(addr)) != 0) {
bytes[len++] = b;
addr = addr.next();
}
String str = new String(bytes, 0, len);
if (b != 0) {
str += "..."; // indicate string truncation
}
return str;
}
public byte readMemoryByte(Address addr) {
byte[] value = readMemory(addr, 1);
return value[0];
}
public byte[] readMemory(Address addr, int length) {
byte[] res = new byte[length];
int len = emulator.getMemState().getChunk(res, addr.getAddressSpace(), addr.getOffset(),
length, false);
if (len == 0) {
Msg.error(this, "Failed to read memory from Emulator at: " + addr);
return null;
}
else if (len < length) {
Msg.error(this,
"Only " + len + " of " + length + " bytes read memory from Emulator at: " + addr);
}
return res;
}
public void writeMemory(Address addr, byte[] bytes) {
emulator.getMemState().setChunk(bytes, addr.getAddressSpace(), addr.getOffset(),
bytes.length);
}
public void writeMemoryValue(Address addr, int size, long value) {
emulator.getMemState().setValue(addr.getAddressSpace(), addr.getOffset(), size, value);
}
/**
* Read a stack value from the memory state.
* @param relativeOffset offset relative to current stack pointer
* @param size data size in bytes
* @param signed true if value read is signed, false if unsigned
* @return value
* @throws Exception error occurs reading stack pointer
*/
public BigInteger readStackValue(int relativeOffset, int size, boolean signed)
throws Exception {
long offset = readRegister(stackPtrReg).longValue() + relativeOffset;
byte[] bytes = readMemory(stackMemorySpace.getAddress(offset), size);
if (program.getMemory().isBigEndian()) {
return BigEndianDataConverter.INSTANCE.getBigInteger(bytes, size, signed);
}
return LittleEndianDataConverter.INSTANCE.getBigInteger(bytes, size, signed);
}
/**
* Write a value onto the stack
* @param relativeOffset offset relative to current stack pointer
* @param size data size in bytes
* @param value
* @throws Exception error occurs reading stack pointer
*/
public void writeStackValue(int relativeOffset, int size, long value) throws Exception {
long offset = readRegister(stackPtrReg).longValue() + relativeOffset;
byte[] bytes = new byte[size];
if (program.getMemory().isBigEndian()) {
BigEndianDataConverter.INSTANCE.getBytes(value, bytes);
}
else {
LittleEndianDataConverter.INSTANCE.getBytes(value, bytes);
}
writeMemory(stackMemorySpace.getAddress(offset), bytes);
}
/**
* Write a value onto the stack
* @param relativeOffset offset relative to current stack pointer
* @param size data size in bytes
* @param value
* @throws Exception error occurs reading stack pointer
*/
public void writeStackValue(int relativeOffset, int size, BigInteger value) throws Exception {
// TODO: verify that sign byte is not added to size of bytes
long offset = readRegister(stackPtrReg).longValue() + relativeOffset;
byte[] bytes;
if (program.getMemory().isBigEndian()) {
bytes = BigEndianDataConverter.INSTANCE.getBytes(value, size);
}
else {
bytes = LittleEndianDataConverter.INSTANCE.getBytes(value, size);
}
writeMemory(stackMemorySpace.getAddress(offset), bytes);
}
/**
* Establish breakpoint
* @param address memory address for new breakpoint
*/
public void setBreakpoint(Address addr) {
emulator.getBreakTable().registerAddressCallback(addr, addressBreak);
}
/**
* Clear breakpoint
* @param address memory address for breakpoint to be cleared
*/
public void clearBreakpoint(Address addr) {
emulator.getBreakTable().unregisterAddressCallback(addr);
}
/**
* Set current context register value.
* Keep in mind that any non-flowing context values will be stripped.
* @param ctxRegValue
*/
public void setContextRegister(RegisterValue ctxRegValue) {
emulator.setContextRegisterValue(ctxRegValue);
}
/**
* Set current context register value.
* Keep in mind that any non-flowing context values will be stripped.
* @param ctxReg context register
* @param value context value
*/
public void setContextRegister(Register ctxReg, BigInteger value) {
emulator.setContextRegisterValue(new RegisterValue(ctxReg, value));
}
/**
* Get the current context register value
* @return context register value or null if not set or unknown
*/
public RegisterValue getContextRegister() {
return emulator.getContextRegisterValue();
}
/**
* Register callback for language defined pcodeop (call other).
* WARNING! Using this method may circumvent the default CALLOTHER emulation support
* when supplied by the Processor module.
* @param pcodeOpName
* @param callback
*/
public void registerCallOtherCallback(String pcodeOpName, BreakCallBack callback) {
emulator.getBreakTable().registerPcodeCallback(pcodeOpName, callback);
}
/**
* Register default callback for language defined pcodeops (call other).
* WARNING! Using this method may circumvent the default CALLOTHER emulation support
* when supplied by the Processor module.
* @param pcodeOpName
* @param callback
*/
public void registerDefaultCallOtherCallback(BreakCallBack callback) {
emulator.getBreakTable().registerPcodeCallback("*", callback);
}
/**
* Unregister callback for language defined pcodeop (call other).
* @param pcodeOpName
*/
public void unregisterCallOtherCallback(String pcodeOpName) {
emulator.getBreakTable().unregisterPcodeCallback(pcodeOpName);
}
/**
* Unregister default callback for language defined pcodeops (call other).
* WARNING! Using this method may circumvent the default CALLOTHER emulation support
* when supplied by the Processor module.
*/
public void unregisterDefaultCallOtherCallback() {
emulator.getBreakTable().unregisterPcodeCallback("*");
}
/**
* Get current execution address
* @return current execution address
*/
public Address getExecutionAddress() {
return emulator.getExecuteAddress();
}
/**
* Start execution at the specified address using the initial context specified.
* Method will block until execution stops. This method will initialize context
* register based upon the program stored context if not already done. In addition,
* both general register value and the context register may be further modified
* via the context parameter if specified.
* @param addr initial program address
* @param context optional context settings which override current program context
* @param monitor
* @return true if execution completes without error (i.e., is at breakpoint)
* @throws CancelledException if execution cancelled via monitor
*/
public boolean run(Address addr, ProcessorContext context, TaskMonitor monitor)
throws CancelledException {
if (emulator.isExecuting()) {
throw new IllegalStateException("Emulator is already running");
}
// Initialize context
ProgramContext programContext = program.getProgramContext();
Register baseContextRegister = programContext.getBaseContextRegister();
RegisterValue contextRegValue = null;
boolean mustSetContextReg = false;
if (baseContextRegister != null) {
contextRegValue = getContextRegister();
if (contextRegValue == null) {
contextRegValue = programContext.getRegisterValue(baseContextRegister, addr);
mustSetContextReg = (contextRegValue != null);
}
}
if (context != null) {
for (Register reg : context.getRegisters()) {
// skip non-base registers
if (reg.isBaseRegister() && context.hasValue(reg)) {
RegisterValue registerValue = context.getRegisterValue(reg);
if (reg.isProcessorContext()) {
if (contextRegValue != null) {
contextRegValue = contextRegValue.combineValues(registerValue);
}
else {
contextRegValue = registerValue;
}
mustSetContextReg = true;
}
else {
BigInteger value = registerValue.getUnsignedValueIgnoreMask();
writeRegister(reg, value);
}
}
}
}
long pcValue = addr.getAddressableWordOffset();
emulator.setExecuteAddress(pcValue);
if (mustSetContextReg) {
setContextRegister(contextRegValue);
}
continueExecution(monitor);
return emulator.isAtBreakpoint();
}
/**
* Continue execution from the current execution address.
* No adjustment will be made to the context beyond the normal
* context flow behavior defined by the language.
* Method will block until execution stops.
* @param monitor
* @return true if execution completes without error (i.e., is at breakpoint)
* @throws CancelledException if execution cancelled via monitor
*/
public synchronized boolean run(TaskMonitor monitor) throws CancelledException {
if (emulator.isExecuting()) {
throw new IllegalStateException("Emulator is already running");
}
continueExecution(monitor);
return emulator.isAtBreakpoint();
}
/**
* Continue execution and block until either a breakpoint hits or error occurs.
* @throws CancelledException if execution was cancelled
*/
private void continueExecution(TaskMonitor monitor) throws CancelledException {
emulator.setHalt(false);
do {
executeInstruction(true, monitor);
}
while (!emulator.getHalt());
}
/**
* Execute instruction at current address
* @param stopAtBreakpoint if true and breakpoint hits at current execution address
* execution will halt without executing instruction.
* @throws CancelledException if execution was cancelled
*/
private void executeInstruction(boolean stopAtBreakpoint, TaskMonitor monitor)
throws CancelledException {
lastError = null;
try {
if (emulator.getLastExecuteAddress() == null) {
setProcessorContext();
}
emulator.executeInstruction(stopAtBreakpoint, monitor);
}
catch (Throwable t) {
// TODO: need to enumerate errors better !!
lastError = t.getMessage();
emulator.setHalt(true); // force execution to stop
if (t instanceof CancelledException) {
throw (CancelledException) t;
}
}
}
/**
* Used when the emulator has had the execution address changed to
* make sure it has a context consistent with the program context
* if there is one.
*/
private void setProcessorContext() {
// this assumes you have set the emulation address
// the emu will have cleared the context for the new address
RegisterValue contextRegisterValue = emulator.getContextRegisterValue();
if (contextRegisterValue != null) {
return;
}
Address executeAddress = emulator.getExecuteAddress();
Instruction instructionAt = program.getListing().getInstructionAt(executeAddress);
if (instructionAt != null) {
RegisterValue disassemblyContext =
instructionAt.getRegisterValue(instructionAt.getBaseContextRegister());
emulator.setContextRegisterValue(disassemblyContext);
}
}
/**
* @return last error message associated with execution failure
*/
public String getLastError() {
return lastError;
}
/**
* Step execution one instruction which may consist of multiple
* pcode operations. No adjustment will be made to the context beyond the normal
* context flow behavior defined by the language.
* Method will block until execution stops.
* @return true if execution completes without error
* @throws CancelledException if execution cancelled via monitor
*/
public synchronized boolean step(TaskMonitor monitor) throws CancelledException {
executeInstruction(true, monitor);
return lastError == null;
}
/**
* Create a new initialized memory block using the current emulator memory state
* @param name block name
* @param start start address of the block
* @param length the size of the block
* @param overlay if true, the block will be created as an OVERLAY which means that a new
* overlay address space will be created and the block will have a starting address at the same
* offset as the given start address parameter, but in the new address space.
* @param monitor
* @return new memory block
* @throws LockException if exclusive lock not in place (see haveLock())
* @throws MemoryConflictException if the new block overlaps with a
* previous block
* @throws AddressOverflowException if the start is beyond the
* address space
* @throws CancelledException user cancelled operation
* @throws DuplicateNameException
*/
public MemoryBlock createMemoryBlockFromMemoryState(String name, final Address start,
final int length, boolean overlay, TaskMonitor monitor) throws MemoryConflictException,
AddressOverflowException, CancelledException, LockException, DuplicateNameException {
if (emulator.isExecuting()) {
throw new IllegalStateException("Emulator must be paused to access memory state");
}
InputStream memStateStream = new InputStream() {
private MemoryState memState = emulator.getMemState();
private byte[] buffer = new byte[1024];
private long nextBufferOffset = start.getOffset();
private int bytesRemaining = length;
private int bufferPos = buffer.length;
@Override
public int read() throws IOException {
if (bytesRemaining <= 0) {
return -1;
}
if (bufferPos == buffer.length) {
int size = Math.min(buffer.length, bytesRemaining);
memState.getChunk(buffer, start.getAddressSpace(), nextBufferOffset, size,
false);
nextBufferOffset += buffer.length;
bufferPos = 0;
}
byte b = buffer[bufferPos++];
--bytesRemaining;
return b;
}
};
MemoryBlock block;
boolean success = false;
int txId = program.startTransaction("Create Memory Block");
try {
block = program.getMemory().createInitializedBlock(name, start, memStateStream, length,
monitor, overlay);
success = true;
}
finally {
program.endTransaction(txId, success);
}
return block;
}
/**
* Enable/Disable tracking of memory writes in the form of an
* address set.
* @param enable
*/
public void enableMemoryWriteTracking(boolean enable) {
if (!enable) {
if (memoryWriteTracker != null) {
memoryWriteTracker.dispose();
memoryWriteTracker = null;
}
return;
}
memoryWriteTracker = new MemoryWriteTracker();
emulator.addMemoryAccessFilter(memoryWriteTracker);
}
/**
* @return address set of memory locations written by the emulator
* if memory write tracking is enabled, otherwise null is returned.
* The address set returned will continue to be updated unless
* memory write tracking becomes disabled.
*/
public AddressSetView getTrackedMemoryWriteSet() {
if (memoryWriteTracker != null) {
return memoryWriteTracker.writeSet;
}
return null;
}
private class MemoryWriteTracker extends MemoryAccessFilter {
AddressSet writeSet = new AddressSet();
@Override
protected void processRead(AddressSpace spc, long off, int size, byte[] values) {
// do nothing
}
@Override
protected void processWrite(AddressSpace spc, long off, int size, byte[] values) {
AddressRange range =
new AddressRangeImpl(spc.getAddress(off), spc.getAddress(off + size - 1));
writeSet.add(range);
}
}
@Override
public boolean unknownAddress(Address address, boolean write) {
if (faultHandler != null) {
return faultHandler.unknownAddress(address, write);
}
Address pc = emulator.getExecuteAddress();
String access = write ? "written" : "read";
Msg.warn(this, "Unknown address " + access + " at " + pc + ": " + address);
return false;
}
@Override
public boolean uninitializedRead(Address address, int size, byte[] buf, int bufOffset) {
if (faultHandler != null) {
return faultHandler.uninitializedRead(address, size, buf, bufOffset);
}
if (emulator.getEmulateExecutionState() == EmulateExecutionState.INSTRUCTION_DECODE) {
return false;
}
Address pc = emulator.getExecuteAddress();
Register reg = program.getRegister(address, size);
if (reg != null) {
Msg.warn(this, "Uninitialized register read at " + pc + ": " + reg);
return true;
}
Msg.warn(this,
"Uninitialized memory read at " + pc + ": " + address.toString(true) + ":" + size);
return true;
}
public Emulator getEmulator() {
return emulator;
}
}

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/* ###
* IP: GHIDRA
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package ghidra.app.emulator;
import ghidra.pcode.memstate.MemoryState;
import ghidra.program.model.address.AddressSpace;
import ghidra.program.model.lang.Language;
class FilteredMemoryState extends MemoryState {
private MemoryAccessFilter filter;
private boolean filterEnabled = true; // used to prevent filtering filter queries
FilteredMemoryState(Language lang) {
super(lang);
}
@Override
public int getChunk(byte[] res, AddressSpace spc, long off, int size,
boolean stopOnUnintialized) {
int readLen = super.getChunk(res, spc, off, size, stopOnUnintialized);
if (filterEnabled && filter != null) {
filterEnabled = false;
try {
filter.filterRead(spc, off, readLen, res);
}
finally {
filterEnabled = true;
}
}
return readLen;
}
@Override
public void setChunk(byte[] res, AddressSpace spc, long off, int size) {
super.setChunk(res, spc, off, size);
if (filterEnabled && filter != null) {
filterEnabled = false;
try {
filter.filterWrite(spc, off, size, res);
}
finally {
filterEnabled = true;
}
}
}
MemoryAccessFilter setFilter(MemoryAccessFilter filter) {
MemoryAccessFilter oldFilter = this.filter;
this.filter = filter;
return oldFilter;
}
}

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/* ###
* IP: GHIDRA
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package ghidra.app.emulator;
import ghidra.program.model.address.AddressSpace;
public abstract class MemoryAccessFilter {
private MemoryAccessFilter prevFilter;
private MemoryAccessFilter nextFilter;
protected Emulator emu;
private boolean filterOnExecutionOnly = true;
final void filterRead(AddressSpace spc, long off, int size, byte [] values) {
if (filterOnExecutionOnly() && !emu.isExecuting()) return; // do not filter idle queries
processRead(spc, off, size, values);
if (nextFilter != null) {
nextFilter.filterRead(spc, off, size, values);
}
}
protected abstract void processRead(AddressSpace spc, long off, int size, byte[] values);
final void filterWrite(AddressSpace spc, long off, int size, byte [] values) {
if (filterOnExecutionOnly() && !emu.isExecuting()) return; // do not filter idle queries
processWrite(spc, off, size, values);
if (nextFilter != null) {
nextFilter.filterWrite(spc, off, size, values);
}
}
protected abstract void processWrite(AddressSpace spc, long off, int size, byte[] values);
final void addFilter(Emulator emu) {
this.emu = emu;
nextFilter = emu.getFilteredMemState().setFilter(this);
if (nextFilter != null) {
nextFilter.prevFilter = this;
}
}
/**
* Dispose this filter which will cause it to be removed from the memory state.
* If overriden, be sure to invoke super.dispose().
*/
public void dispose() {
if (nextFilter != null) {
nextFilter.prevFilter = prevFilter;
}
if (prevFilter != null) {
prevFilter.nextFilter = nextFilter;
}
else {
emu.getFilteredMemState().setFilter(nextFilter);
}
}
public boolean filterOnExecutionOnly() {
return filterOnExecutionOnly;
}
public void setFilterOnExecutionOnly(boolean filterOnExecutionOnly) {
this.filterOnExecutionOnly = filterOnExecutionOnly;
}
// public void compare(String id);
// public void clear();
// public void updateFlags(String id);
}

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/* ###
* IP: GHIDRA
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package ghidra.app.emulator.memory;
import java.util.*;
import ghidra.pcode.memstate.MemoryPage;
import ghidra.program.model.address.Address;
import ghidra.program.model.address.AddressSetView;
public class CompositeLoadImage implements MemoryLoadImage {
private List<MemoryLoadImage> providers = new ArrayList<MemoryLoadImage>();
private HashMap<MemoryLoadImage, AddressSetView> addrSets =
new HashMap<MemoryLoadImage, AddressSetView>();
public void addProvider(MemoryLoadImage provider, AddressSetView view) {
if (view == null) {
providers.add(providers.size(), provider);
}
else {
providers.add(0, provider);
}
addrSets.put(provider, view);
}
@Override
public byte[] loadFill(byte[] buf, int size, Address addr, int bufOffset,
boolean generateInitializedMask) {
// Warning: this implementation assumes that the memory page (specified by addr and size)
// will only correspond to a single program image.
Address endAddr = addr.add(size - 1);
for (MemoryLoadImage provider : providers) {
AddressSetView view = addrSets.get(provider);
if (view == null || view.intersects(addr, endAddr)) {
return provider.loadFill(buf, size, addr, bufOffset, generateInitializedMask);
}
}
return generateInitializedMask ? MemoryPage.getInitializedMask(size, false) : null;
}
@Override
public void writeBack(byte[] bytes, int size, Address addr, int offset) {
// Warning: this implementation assumes that the memory page (specified by addr and size)
// will only correspond to a single program image.
Address endAddr = addr.add(size - 1);
for (MemoryLoadImage provider : providers) {
AddressSetView view = addrSets.get(provider);
if (view == null || view.intersects(addr, endAddr)) {
provider.writeBack(bytes, size, addr, offset);
}
}
}
@Override
public void dispose() {
for (MemoryLoadImage provider : providers) {
provider.dispose();
}
}
}

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/* ###
* IP: GHIDRA
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package ghidra.app.emulator.memory;
import ghidra.app.emulator.state.RegisterState;
import ghidra.program.model.address.AddressSetView;
public interface EmulatorLoadData {
public MemoryLoadImage getMemoryLoadImage();
public RegisterState getInitialRegisterState();
public default AddressSetView getView() {
return null;
}
}

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/* ###
* IP: GHIDRA
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package ghidra.app.emulator.memory;
import ghidra.pcode.memstate.*;
import ghidra.program.model.address.AddressSpace;
/// A kind of MemoryBank which retrieves its data from an underlying LoadImage
///
/// Any bytes requested on the bank which lie in the LoadImage are retrieved from
/// the LoadImage. Other addresses in the space are filled in with zero.
/// This bank cannot be written to.
public class MemoryImage extends MemoryBank {
private MemoryLoadImage loader; // The underlying LoadImage
/// A MemoryImage needs everything a basic memory bank needs and is needs to know
/// the underlying LoadImage object to forward read requests to.
/// \param spc is the address space associated with the memory bank
/// \param ws is the number of bytes in the preferred wordsize (must be power of 2)
/// \param ps is the number of bytes in a page (must be power of 2)
/// \param ld is the underlying LoadImage
public MemoryImage(AddressSpace spc, boolean isBigEndian, int ps, MemoryLoadImage ld,
MemoryFaultHandler faultHandler) {
super(spc, isBigEndian, ps, faultHandler);
loader = ld;
}
/// Retrieve an aligned page from the bank. First an attempt is made to retrieve the
/// page from the LoadImage, which may do its own zero filling. If the attempt fails, the
/// page is entirely filled in with zeros.
@Override
public MemoryPage getPage(long addr) {
MemoryPage page = new MemoryPage(getPageSize());
// Assume that -addr- is page aligned
AddressSpace spc = getSpace();
byte[] maskUpdate =
loader.loadFill(page.data, getPageSize(), spc.getAddress(addr), 0, true);
page.setInitialized(0, getPageSize(), maskUpdate);
return page;
}
@Override
protected void setPage(long addr, byte[] val, int skip, int size, int bufOffset) {
AddressSpace spc = getSpace();
loader.writeBack(val, size, spc.getAddress(addr), bufOffset);
}
@Override
protected void setPageInitialized(long addr, boolean initialized, int skip, int size,
int bufOffset) {
// unsupported
}
}

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/* ###
* IP: GHIDRA
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package ghidra.app.emulator.memory;
import ghidra.pcode.loadimage.LoadImage;
import ghidra.program.model.address.Address;
public interface MemoryLoadImage extends LoadImage {
public void writeBack(byte[] bytes, int size, Address addr, int offset);
public void dispose();
}

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/* ###
* IP: GHIDRA
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package ghidra.app.emulator.memory;
import java.util.Arrays;
import ghidra.pcode.error.LowlevelError;
import ghidra.pcode.memstate.MemoryFaultHandler;
import ghidra.pcode.memstate.MemoryPage;
import ghidra.program.model.address.*;
import ghidra.program.model.listing.Program;
import ghidra.program.model.mem.*;
import ghidra.util.Msg;
// Derived from ProgramMappedMemory
public class ProgramLoadImage {
private Program program;
private AddressSetView initializedAddressSet;
private MemoryFaultHandler faultHandler;
public ProgramLoadImage(Program program, MemoryFaultHandler faultHandler) {
this.program = program;
Memory memory = program.getMemory();
initializedAddressSet = memory.getLoadedAndInitializedAddressSet();
for (MemoryBlock block : memory.getBlocks()) {
if (!block.isInitialized() && (block instanceof MappedMemoryBlock)) {
initializedAddressSet = addMappedInitializedMemory((MappedMemoryBlock) block);
}
}
this.faultHandler = faultHandler;
// TODO: consider adding program consumer (would require proper dispose)
}
private AddressSetView addMappedInitializedMemory(MappedMemoryBlock mappedBlock) {
long size = mappedBlock.getSize();
if (size <= 0) {
// TODO: can't handle massive mapped blocks
return initializedAddressSet;
}
AddressSet modifiedSet = new AddressSet(initializedAddressSet);
Address mapStart = mappedBlock.getOverlayedMinAddress();
Address mapEnd = mapStart.add(size - 1);
AddressSet mappedAreas = initializedAddressSet.intersectRange(mapStart, mapEnd);
for (AddressRange range : mappedAreas) {
Address start = mappedBlock.getStart().add(range.getMinAddress().subtract(mapStart));
Address end = mappedBlock.getStart().add(range.getMaxAddress().subtract(mapStart));
modifiedSet.add(start, end);
}
return modifiedSet;
}
public void dispose() {
// do nothing
}
// TODO: Need to investigate program write-back transaction issues -
// it could also be very expensive writing memory without some form of write-back cache
public void write(byte[] bytes, int size, Address addr, int offset) {
Memory memory = program.getMemory();
int currentOffset = offset;
int remaining = size;
Address nextAddr = addr;
Address endAddr;
try {
endAddr = addr.addNoWrap(size - 1);
}
catch (AddressOverflowException e) {
throw new LowlevelError(
"Illegal memory write request: " + addr + ", length=" + size + " bytes");
}
while (true) {
int chunkSize = remaining;
AddressRangeIterator it = initializedAddressSet.getAddressRanges(nextAddr, true);
AddressRange range = it.hasNext() ? it.next() : null;
///
/// Begin change for addressSet changes - wcb
///
if (range == null) {
// nextAddr not in memory and is bigger that any initialized memory
handleWriteFault(bytes, currentOffset, remaining, nextAddr);
break;
}
else if (range.contains(nextAddr)) {
// nextAddr is in memory
if (endAddr.compareTo(range.getMaxAddress()) > 0) {
chunkSize = (int) (range.getMaxAddress().subtract(nextAddr) + 1);
}
try {
memory.setBytes(nextAddr, bytes, currentOffset, chunkSize);
}
catch (MemoryAccessException e) {
throw new LowlevelError("Unexpected memory write error: " + e.getMessage());
}
}
else {
// nextAddr not in initialized memory, but is less than some initialized range
Address rangeAddr = range.getMinAddress();
if (!rangeAddr.getAddressSpace().equals(addr.getAddressSpace())) {
handleWriteFault(bytes, currentOffset, remaining, nextAddr);
break;
}
long gapSize = rangeAddr.subtract(nextAddr);
chunkSize = (int) Math.min(gapSize, remaining);
handleWriteFault(bytes, currentOffset, chunkSize, nextAddr);
}
///
/// End change for addressSet changes - wcb
///
if (chunkSize == remaining) {
break; // done
}
// prepare for next chunk
try {
nextAddr = nextAddr.addNoWrap(chunkSize);
}
catch (AddressOverflowException e) {
throw new LowlevelError("Unexpected error: " + e.getMessage());
}
currentOffset += chunkSize;
remaining -= chunkSize;
}
}
private void handleWriteFault(byte[] bytes, int currentOffset, int remaining,
Address nextAddr) {
// TODO: Should we create blocks or convert to initialized as needed ?
}
public byte[] read(byte[] bytes, int size, Address addr, int offset,
boolean generateInitializedMask) {
Memory memory = program.getMemory();
int currentOffset = offset;
int remaining = size;
Address nextAddr = addr;
Address endAddr;
byte[] initializedMask = null;
try {
endAddr = addr.addNoWrap(size - 1);
}
catch (AddressOverflowException e) {
throw new LowlevelError(
"Illegal memory read request: " + addr + ", length=" + size + " bytes");
}
while (true) {
int chunkSize = remaining;
///
/// Begin change for addressSet changes - wcb
///
AddressRangeIterator it = initializedAddressSet.getAddressRanges(nextAddr, true);
AddressRange range = it.hasNext() ? it.next() : null;
if (range == null) {
if (generateInitializedMask) {
initializedMask = getInitializedMask(bytes.length, offset, currentOffset,
remaining, initializedMask);
}
else {
handleReadFault(bytes, currentOffset, remaining, nextAddr);
}
break;
}
else if (range.contains(nextAddr)) {
// nextAddr found in initialized memory
if (endAddr.compareTo(range.getMaxAddress()) > 0) {
chunkSize = (int) (range.getMaxAddress().subtract(nextAddr) + 1);
}
try {
memory.getBytes(nextAddr, bytes, currentOffset, chunkSize);
}
catch (MemoryAccessException e) {
//throw new LowlevelError("Unexpected memory read error: " + e.getMessage());
Msg.warn(this, "Unexpected memory read error: " + e.getMessage());
}
}
else {
Address rangeAddr = range.getMinAddress();
if (!rangeAddr.getAddressSpace().equals(addr.getAddressSpace())) {
if (generateInitializedMask) {
initializedMask = getInitializedMask(bytes.length, offset, currentOffset,
remaining, initializedMask);
}
else {
handleReadFault(bytes, currentOffset, remaining, nextAddr);
}
break;
}
long gapSize = rangeAddr.subtract(nextAddr);
chunkSize = (gapSize > 0) ? (int) Math.min(gapSize, remaining) : remaining;
if (generateInitializedMask) {
initializedMask = getInitializedMask(bytes.length, offset, currentOffset,
chunkSize, initializedMask);
}
else {
handleReadFault(bytes, currentOffset, chunkSize, nextAddr);
}
}
///
/// End change for addressSet changes - wcb
///
if (chunkSize == remaining) {
break; // done
}
// prepare for next chunk
try {
nextAddr = nextAddr.addNoWrap(chunkSize);
}
catch (AddressOverflowException e) {
throw new LowlevelError("Unexpected error: " + e.getMessage());
}
currentOffset += chunkSize;
remaining -= chunkSize;
}
return initializedMask;
}
private static byte[] getInitializedMask(int bufsize, int initialOffset,
int uninitializedOffset, int uninitializedSize, byte[] initializedMask) {
if (initializedMask == null) {
initializedMask = MemoryPage.getInitializedMask(bufsize, 0, initialOffset, false);
}
MemoryPage.setUninitialized(initializedMask, uninitializedOffset, uninitializedSize);
return initializedMask;
}
private void handleReadFault(byte[] bytes, int offset, int size, Address addr) {
// NOTE: This can trigger a load from a different external library depending upon the specific fault handler installed
Arrays.fill(bytes, offset, offset + size, (byte) 0);
if (faultHandler != null) {
faultHandler.uninitializedRead(addr, size, bytes, size);
}
}
public AddressSetView getInitializedAddressSet() {
return initializedAddressSet;
}
}

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/* ###
* IP: GHIDRA
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package ghidra.app.emulator.memory;
import ghidra.program.model.address.Address;
public class ProgramMappedLoadImage implements MemoryLoadImage {
private ProgramMappedMemory pmm;
//private Language lang;
public ProgramMappedLoadImage(ProgramMappedMemory memory) {
this.pmm = memory;
//this.lang = memory.getProgram().getLanguage();
}
@Override
public byte[] loadFill(byte[] bytes, int size, Address addr, int offset, boolean generateInitializedMask) {
return pmm.read(bytes, size, addr, offset, generateInitializedMask);
// boolean initialized = false;
// for (byte b : bytes) {
// if (b != 0) {
// initialized = true;
// break;
// }
// }
// return generateInitializedMask ? MemoryPage.getInitializedMask(size, initialized) : null;
}
@Override
public void writeBack(byte[] bytes, int size, Address addr, int offset) {
pmm.write(bytes, size, addr, offset);
}
@Override
public void dispose() {
pmm.dispose();
}
}

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/* ###
* IP: GHIDRA
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package ghidra.app.emulator.memory;
import java.util.Arrays;
import ghidra.pcode.error.LowlevelError;
import ghidra.pcode.memstate.MemoryFaultHandler;
import ghidra.pcode.memstate.MemoryPage;
import ghidra.program.model.address.*;
import ghidra.program.model.listing.Program;
import ghidra.program.model.mem.*;
import ghidra.util.Msg;
public class ProgramMappedMemory {
private Program program;
private AddressSetView initializedAddressSet;
private MemoryFaultHandler faultHandler;
public ProgramMappedMemory(Program program, MemoryFaultHandler faultHandler) {
this.program = program;
Memory memory = program.getMemory();
initializedAddressSet = memory.getLoadedAndInitializedAddressSet();
for (MemoryBlock block : memory.getBlocks()) {
if (!block.isInitialized() && (block instanceof MappedMemoryBlock)) {
initializedAddressSet = addMappedInitializedMemory((MappedMemoryBlock) block);
}
}
program.addConsumer(this);
this.faultHandler = faultHandler;
}
private AddressSetView addMappedInitializedMemory(MappedMemoryBlock mappedBlock) {
long size = mappedBlock.getSize();
if (size <= 0) {
// TODO: can't handle massive mapped blocks
return initializedAddressSet;
}
AddressSet modifiedSet = new AddressSet(initializedAddressSet);
Address mapStart = mappedBlock.getOverlayedMinAddress();
Address mapEnd = mapStart.add(size - 1);
AddressSet mappedAreas = initializedAddressSet.intersectRange(mapStart, mapEnd);
for (AddressRange range : mappedAreas) {
Address start = mappedBlock.getStart().add(range.getMinAddress().subtract(mapStart));
Address end = mappedBlock.getStart().add(range.getMaxAddress().subtract(mapStart));
modifiedSet.add(start, end);
}
return modifiedSet;
}
public Program getProgram() {
return program;
}
public void dispose() {
if (program != null) {
program.release(this);
program = null;
}
}
// TODO: Need to investigate program write-back transaction issues -
// it could also be very expensive writing memory without some form of write-back cache
public void write(byte[] bytes, int size, Address addr, int offset) {
Memory memory = program.getMemory();
int currentOffset = offset;
int remaining = size;
Address nextAddr = addr;
Address endAddr;
try {
endAddr = addr.addNoWrap(size - 1);
}
catch (AddressOverflowException e) {
throw new LowlevelError(
"Illegal memory write request: " + addr + ", length=" + size + " bytes");
}
while (true) {
int chunkSize = remaining;
AddressRangeIterator it = initializedAddressSet.getAddressRanges(nextAddr, true);
AddressRange range = it.hasNext() ? it.next() : null;
///
/// Begin change for addressSet changes - wcb
///
if (range == null) {
// nextAddr not in memory and is bigger that any initialized memory
handleWriteFault(bytes, currentOffset, remaining, nextAddr);
break;
}
else if (range.contains(nextAddr)) {
// nextAddr is in memory
if (endAddr.compareTo(range.getMaxAddress()) > 0) {
chunkSize = (int) (range.getMaxAddress().subtract(nextAddr) + 1);
}
try {
memory.setBytes(nextAddr, bytes, currentOffset, chunkSize);
}
catch (MemoryAccessException e) {
throw new LowlevelError("Unexpected memory write error: " + e.getMessage());
}
}
else {
// nextAddr not in initialized memory, but is less than some initialized range
Address rangeAddr = range.getMinAddress();
if (!rangeAddr.getAddressSpace().equals(addr.getAddressSpace())) {
handleWriteFault(bytes, currentOffset, remaining, nextAddr);
break;
}
long gapSize = rangeAddr.subtract(nextAddr);
chunkSize = (int) Math.min(gapSize, remaining);
handleWriteFault(bytes, currentOffset, chunkSize, nextAddr);
}
///
/// End change for addressSet changes - wcb
///
if (chunkSize == remaining) {
break; // done
}
// prepare for next chunk
try {
nextAddr = nextAddr.addNoWrap(chunkSize);
}
catch (AddressOverflowException e) {
throw new LowlevelError("Unexpected error: " + e.getMessage());
}
currentOffset += chunkSize;
remaining -= chunkSize;
}
}
private void handleWriteFault(byte[] bytes, int currentOffset, int remaining,
Address nextAddr) {
// TODO: Should we create blocks or convert to initialized as needed ?
}
public byte[] read(byte[] bytes, int size, Address addr, int offset,
boolean generateInitializedMask) {
Memory memory = program.getMemory();
int currentOffset = offset;
int remaining = size;
Address nextAddr = addr;
Address endAddr;
byte[] initializedMask = null;
try {
endAddr = addr.addNoWrap(size - 1);
}
catch (AddressOverflowException e) {
throw new LowlevelError(
"Illegal memory read request: " + addr + ", length=" + size + " bytes");
}
while (true) {
int chunkSize = remaining;
///
/// Begin change for addressSet changes - wcb
///
AddressRangeIterator it = initializedAddressSet.getAddressRanges(nextAddr, true);
AddressRange range = it.hasNext() ? it.next() : null;
if (range == null) {
if (generateInitializedMask) {
initializedMask = getInitializedMask(bytes.length, offset, currentOffset,
remaining, initializedMask);
}
else {
handleReadFault(bytes, currentOffset, remaining, nextAddr);
}
break;
}
else if (range.contains(nextAddr)) {
// nextAddr found in initialized memory
if (endAddr.compareTo(range.getMaxAddress()) > 0) {
chunkSize = (int) (range.getMaxAddress().subtract(nextAddr) + 1);
}
try {
memory.getBytes(nextAddr, bytes, currentOffset, chunkSize);
}
catch (MemoryAccessException e) {
//throw new LowlevelError("Unexpected memory read error: " + e.getMessage());
Msg.warn(this, "Unexpected memory read error: " + e.getMessage());
}
}
else {
Address rangeAddr = range.getMinAddress();
if (!rangeAddr.getAddressSpace().equals(addr.getAddressSpace())) {
if (generateInitializedMask) {
initializedMask = getInitializedMask(bytes.length, offset, currentOffset,
remaining, initializedMask);
}
else {
handleReadFault(bytes, currentOffset, remaining, nextAddr);
}
break;
}
long gapSize = rangeAddr.subtract(nextAddr);
chunkSize = (gapSize > 0) ? (int) Math.min(gapSize, remaining) : remaining;
if (generateInitializedMask) {
initializedMask = getInitializedMask(bytes.length, offset, currentOffset,
chunkSize, initializedMask);
}
else {
handleReadFault(bytes, currentOffset, chunkSize, nextAddr);
}
}
///
/// End change for addressSet changes - wcb
///
if (chunkSize == remaining) {
break; // done
}
// prepare for next chunk
try {
nextAddr = nextAddr.addNoWrap(chunkSize);
}
catch (AddressOverflowException e) {
throw new LowlevelError("Unexpected error: " + e.getMessage());
}
currentOffset += chunkSize;
remaining -= chunkSize;
}
return initializedMask;
}
private static byte[] getInitializedMask(int bufsize, int initialOffset,
int uninitializedOffset, int uninitializedSize, byte[] initializedMask) {
if (initializedMask == null) {
initializedMask = MemoryPage.getInitializedMask(bufsize, 0, initialOffset, false);
}
MemoryPage.setUninitialized(initializedMask, uninitializedOffset, uninitializedSize);
return initializedMask;
}
private void handleReadFault(byte[] bytes, int offset, int size, Address addr) {
// NOTE: This can trigger a load from a different external library depending upon the specific fault handler installed
Arrays.fill(bytes, offset, offset + size, (byte) 0);
if (faultHandler != null) {
faultHandler.uninitializedRead(addr, size, bytes, size);
}
}
public AddressSetView getInitializedAddressSet() {
return initializedAddressSet;
}
}

View file

@ -0,0 +1,83 @@
/* ###
* IP: GHIDRA
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package ghidra.app.emulator.state;
import generic.stl.Pair;
import ghidra.program.model.lang.Language;
import ghidra.util.*;
import java.util.*;
public class DumpMiscState implements RegisterState {
private Map<String, Pair<Boolean, byte[]>> context =
new HashMap<String, Pair<Boolean, byte[]>>();
private DataConverter dc;
public DumpMiscState(Language lang) {
dc =
lang.isBigEndian() ? BigEndianDataConverter.INSTANCE
: LittleEndianDataConverter.INSTANCE;
}
@Override
public void dispose() {
context.clear();
}
@Override
public Set<String> getKeys() {
return context.keySet();
}
@Override
public List<byte[]> getVals(String key) {
List<byte[]> list = new ArrayList<byte[]>();
Pair<Boolean, byte[]> pair = context.get(key);
if (pair != null && pair.second != null) {
list.add(pair.second);
}
return list;
}
@Override
public List<Boolean> isInitialized(String key) {
List<Boolean> list = new ArrayList<Boolean>();
Pair<Boolean, byte[]> pair = context.get(key);
if (pair != null && pair.first != null) {
list.add(pair.first);
}
else {
list.add(Boolean.FALSE);
}
return list;
}
@Override
public void setVals(String key, byte[] vals, boolean setInitiailized) {
Pair<Boolean, byte[]> pair = new Pair<Boolean, byte[]>(setInitiailized, vals);
context.put(key, pair);
}
@Override
public void setVals(String key, long val, int size, boolean setInitiailized) {
byte[] bytes = new byte[size];
dc.getBytes(val, size, bytes, 0);
setVals(key, bytes, setInitiailized);
}
}

View file

@ -0,0 +1,39 @@
/* ###
* IP: GHIDRA
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package ghidra.app.emulator.state;
import ghidra.pcode.memstate.MemoryBank;
import ghidra.pcode.memstate.MemoryPageOverlay;
import ghidra.program.model.address.AddressSpace;
public class FilteredMemoryPageOverlay extends MemoryPageOverlay {
private boolean writeBack;
public FilteredMemoryPageOverlay(AddressSpace spc, MemoryBank ul, boolean writeBack) {
super(spc, ul, ul.getMemoryFaultHandler());
this.writeBack = writeBack;
}
@Override
public void setChunk(long offset, int size, byte[] val) {
super.setChunk(offset, size, val);
if (writeBack) {
underlie.setChunk(offset, size, val);
}
}
}

View file

@ -0,0 +1,34 @@
/* ###
* IP: GHIDRA
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package ghidra.app.emulator.state;
import ghidra.pcode.memstate.MemoryFaultHandler;
import ghidra.pcode.memstate.MemoryPageBank;
import ghidra.program.model.address.AddressSpace;
import ghidra.program.model.lang.Language;
public class FilteredRegisterBank extends MemoryPageBank {
//private final RegisterState regState;
//private final boolean writeBack;
public FilteredRegisterBank(AddressSpace spc, int ps, RegisterState initState, Language lang, boolean writeBack, MemoryFaultHandler faultHandler) {
super(spc, lang.isBigEndian(), ps, faultHandler);
//regState = initState;
//this.writeBack = writeBack;
}
}

View file

@ -0,0 +1,35 @@
/* ###
* IP: GHIDRA
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package ghidra.app.emulator.state;
import java.util.List;
import java.util.Set;
public interface RegisterState {
public Set<String> getKeys();
public List<byte[]> getVals(String key);
public List<Boolean> isInitialized(String key);
public void setVals(String key, byte[] vals, boolean setInitiailized);
public void setVals(String key, long val, int size, boolean setInitiailized);
public void dispose();
}

View file

@ -31,6 +31,8 @@ import ghidra.program.model.listing.Instruction;
import ghidra.program.model.pcode.PcodeOp;
import ghidra.program.model.pcode.Varnode;
import ghidra.util.Msg;
import ghidra.util.exception.CancelledException;
import ghidra.util.task.TaskMonitor;
import ghidra.util.task.TaskMonitorAdapter;
/// \brief A SLEIGH based implementation of the Emulate interface
///
@ -78,7 +80,8 @@ public class Emulate {
pcReg = lang.getProgramCounter();
breaktable = b;
breaktable.setEmulate(this);
memBuffer = new EmulateMemoryStateBuffer(s, addrFactory.getDefaultAddressSpace().getMinAddress());
memBuffer =
new EmulateMemoryStateBuffer(s, addrFactory.getDefaultAddressSpace().getMinAddress());
uniqueBank =
new UniqueMemoryBank(lang.getAddressFactory().getUniqueSpace(), lang.isBigEndian());
@ -91,24 +94,24 @@ public class Emulate {
initInstuctionStateModifier();
}
public void dispose() {
executionState = EmulateExecutionState.STOPPED;
}
@SuppressWarnings("unchecked")
private void initInstuctionStateModifier() {
String classname =
language.getProperty(GhidraLanguagePropertyKeys.EMULATE_INSTRUCTION_STATE_MODIFIER_CLASS);
String classname = language.getProperty(
GhidraLanguagePropertyKeys.EMULATE_INSTRUCTION_STATE_MODIFIER_CLASS);
if (classname == null) {
return;
}
try {
Class<?> c = Class.forName(classname);
if (!EmulateInstructionStateModifier.class.isAssignableFrom(c)) {
Msg.error(this, "Language " + language.getLanguageID() +
" does not specify a valid " +
GhidraLanguagePropertyKeys.EMULATE_INSTRUCTION_STATE_MODIFIER_CLASS);
Msg.error(this,
"Language " + language.getLanguageID() + " does not specify a valid " +
GhidraLanguagePropertyKeys.EMULATE_INSTRUCTION_STATE_MODIFIER_CLASS);
throw new RuntimeException(classname + " does not implement interface " +
EmulateInstructionStateModifier.class.getName());
}
@ -121,8 +124,9 @@ public class Emulate {
catch (Exception e) {
Msg.error(this, "Language " + language.getLanguageID() + " does not specify a valid " +
GhidraLanguagePropertyKeys.EMULATE_INSTRUCTION_STATE_MODIFIER_CLASS);
throw new RuntimeException("Failed to instantiate " + classname + " for language " +
language.getLanguageID(), e);
throw new RuntimeException(
"Failed to instantiate " + classname + " for language " + language.getLanguageID(),
e);
}
}
@ -367,11 +371,12 @@ public class Emulate {
/// and invoked as needed for the current address. If this routine is invoked while execution is
/// in the middle of a machine instruction, execution is continued until the current instruction
/// completes.
public void executeInstruction(boolean stopAtBreakpoint) throws LowlevelError,
InstructionDecodeException {
public void executeInstruction(boolean stopAtBreakpoint, TaskMonitor monitor)
throws CancelledException, LowlevelError, InstructionDecodeException {
if (executionState == EmulateExecutionState.STOPPED) {
if (last_execute_address == null && instructionStateModifier != null) {
instructionStateModifier.initialExecuteCallback(this, current_address, nextContextRegisterValue);
instructionStateModifier.initialExecuteCallback(this, current_address,
nextContextRegisterValue);
}
if (breaktable.doAddressBreak(current_address) && stopAtBreakpoint) {
executionState = EmulateExecutionState.BREAKPOINT;
@ -400,6 +405,7 @@ public class Emulate {
}
executionState = EmulateExecutionState.EXECUTE;
do {
monitor.checkCanceled();
executeCurrentOp();
}
while (executionState == EmulateExecutionState.EXECUTE);
@ -441,8 +447,8 @@ public class Emulate {
OpBehavior behave = raw.getBehavior();
if (behave == null) {
// unsupported opcode
throw new LowlevelError("Unsupported pcode op (opcode=" + op.getOpcode() + ", seq=" +
op.getSeqnum() + ")");
throw new LowlevelError(
"Unsupported pcode op (opcode=" + op.getOpcode() + ", seq=" + op.getSeqnum() + ")");
}
if (behave instanceof UnaryOpBehavior) {
UnaryOpBehavior uniaryBehave = (UnaryOpBehavior) behave;
@ -450,16 +456,14 @@ public class Emulate {
Varnode outvar = op.getOutput();
if (in1var.getSize() > 8 || outvar.getSize() > 8) {
BigInteger in1 = memstate.getBigInteger(op.getInput(0), false);
BigInteger out =
uniaryBehave.evaluateUnary(op.getOutput().getSize(), op.getInput(0).getSize(),
in1);
BigInteger out = uniaryBehave.evaluateUnary(op.getOutput().getSize(),
op.getInput(0).getSize(), in1);
memstate.setValue(op.getOutput(), out);
}
else {
long in1 = memstate.getValue(op.getInput(0));
long out =
uniaryBehave.evaluateUnary(op.getOutput().getSize(), op.getInput(0).getSize(),
in1);
long out = uniaryBehave.evaluateUnary(op.getOutput().getSize(),
op.getInput(0).getSize(), in1);
memstate.setValue(op.getOutput(), out);
}
fallthruOp();
@ -471,17 +475,15 @@ public class Emulate {
if (in1var.getSize() > 8 || outvar.getSize() > 8) {
BigInteger in1 = memstate.getBigInteger(op.getInput(0), false);
BigInteger in2 = memstate.getBigInteger(op.getInput(1), false);
BigInteger out =
binaryBehave.evaluateBinary(outvar.getSize(), op.getInput(0).getSize(), in1,
in2);
BigInteger out = binaryBehave.evaluateBinary(outvar.getSize(),
op.getInput(0).getSize(), in1, in2);
memstate.setValue(outvar, out);
}
else {
long in1 = memstate.getValue(op.getInput(0));
long in2 = memstate.getValue(op.getInput(1));
long out =
binaryBehave.evaluateBinary(outvar.getSize(), op.getInput(0).getSize(), in1,
in2);
long out = binaryBehave.evaluateBinary(outvar.getSize(), op.getInput(0).getSize(),
in1, in2);
memstate.setValue(outvar, out);
}
fallthruOp(); // All binary ops are fallthrus
@ -762,4 +764,3 @@ public class Emulate {
- PcodeOpRaw and
- VarnodeData
*/

View file

@ -0,0 +1,10 @@
See the example emulation scripts contained within Ghidra/Features/Base/ghidra_scripts.
Sample scripts deobExampleX86 and deobHookExampleX86 may be built under Linux.
cc -std=c99 -Wimplicit-function-declaration -o deobExampleX86 deobExample.c
cc -std=c99 -Wimplicit-function-declaration -o deobHookExampleX86 deobHookExample.c
Once these examples have been compiled they may be imported into a Ghidra project and the
corresponding Ghidra Scripts (EmuX86DeobfuscateExampleScript and EmuX86GccDeobfuscateHookExampleScript)
used to demonstrate the use of the EmulatorHelper class.

View file

@ -0,0 +1,100 @@
/* ###
* IP: GHIDRA
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
int length(char *s) {
int len = 0;
while (*s++ != 0) {
++len;
}
return len;
}
const char data[] = {
0xec,
0xc3,
0xd8,
0xd9,
0xde,
0x8a,
0xcf,
0xc4,
0xde,
0xd8,
0xd3,
0x00,
0xf9,
0xcf,
0xc9,
0xc5,
0xc4,
0xce,
0x8a,
0xcf,
0xc4,
0xde,
0xd8,
0xd3,
0x00,
0xfe,
0xc2,
0xc3,
0xd8,
0xce,
0x8a,
0xcf,
0xc4,
0xde,
0xd8,
0xd3,
0x00,
0x00
};
char buffer[64];
char * deobfuscate(char *src, char *dst, int len) {
char *ptr = dst;
for (int i = 0; i < len; i++) {
*ptr++ = *src++ ^ 0xAA;
}
*ptr = 0;
return dst;
}
void use_string(char * str, int index) {
// fprintf(stderr, "String[%d]: %s\n", index, str);
}
int main (int argc, char **argv) {
char *ptr = (char *)data;
int index = 0;
while (*ptr != 0) {
int len = length(ptr);
char *str = deobfuscate(ptr, buffer, len);
use_string(str, index++);
ptr += len + 1;
}
return 0;
}
#ifndef __x86_64
int _start() {
char *argv[] = { "deobExample" };
return main(1, argv);
}
#endif

View file

@ -0,0 +1,120 @@
/* ###
* IP: GHIDRA
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#ifdef __x86_64
#include <malloc.h>
#include <string.h>
#else
// Library routine not linked in for cross-build
void * malloc(int size) {
// missing implementation
return (void *)0;
}
void free(void *ptr) {
// missing implementation
}
int strlen(char *s) {
int len = 0;
while (*s++ != 0) {
++len;
}
return len;
}
#endif
const char data[] = {
0xec,
0xc3,
0xd8,
0xd9,
0xde,
0x8a,
0xcf,
0xc4,
0xde,
0xd8,
0xd3,
0x00,
0xf9,
0xcf,
0xc9,
0xc5,
0xc4,
0xce,
0x8a,
0xcf,
0xc4,
0xde,
0xd8,
0xd3,
0x00,
0xfe,
0xc2,
0xc3,
0xd8,
0xce,
0x8a,
0xcf,
0xc4,
0xde,
0xd8,
0xd3,
0x00,
0x00
};
char * deobfuscate(char *src, int len) {
char *buf = (char *)malloc(len + 1);
char *ptr = buf;
for (int i = 0; i < len; i++) {
*ptr++ = *src++ ^ 0xAA;
}
*ptr = 0;
return buf;
}
void use_string(char * str, int index) {
// fprintf(stderr, "String[%d]: %s\n", index, str);
}
int main (int argc, char **argv) {
char *ptr = (char *)data;
int index = 0;
while (*ptr != 0) {
int len = strlen(ptr);
char *str = deobfuscate(ptr, len);
use_string(str, index++);
free(str);
ptr += len + 1;
}
return 0;
}
#ifndef __x86_64
int _start() {
char *argv[] = { "deobExample" };
return main(1, argv);
}
#endif

View file

@ -39,6 +39,7 @@ GhidraClass/ExerciseFiles/Advanced/override.so||GHIDRA||||END|
GhidraClass/ExerciseFiles/Advanced/setRegister||GHIDRA||||END|
GhidraClass/ExerciseFiles/Advanced/sharedReturn||GHIDRA||||END|
GhidraClass/ExerciseFiles/Advanced/switch||GHIDRA||||END|
GhidraClass/ExerciseFiles/Emulation/Source/README.txt||GHIDRA||||END|
GhidraClass/ExerciseFiles/VersionTracking/WallaceSrc.exe||GHIDRA||||END|
GhidraClass/ExerciseFiles/VersionTracking/WallaceVersion2.exe||GHIDRA||||END|
GhidraClass/ExerciseFiles/WinhelloCPP/WinHelloCPP.exe||GHIDRA||||END|