Package ghidra.pcode.exec.trace

Class TraceMemoryStatePcodeExecutorStatePiece

java.lang.Object

ghidra.pcode.exec.AbstractLongOffsetPcodeExecutorStatePiece<byte[],TraceMemoryState,AddressSpace>

ghidra.pcode.exec.trace.TraceMemoryStatePcodeExecutorStatePiece

All Implemented Interfaces:

PcodeExecutorStatePiece<byte[],TraceMemoryState>

public class TraceMemoryStatePcodeExecutorStatePiece
extends AbstractLongOffsetPcodeExecutorStatePiece<byte[],TraceMemoryState,AddressSpace>

The p-code execute state piece for TraceMemoryState

This state piece is meant to be used as an auxiliary to a concrete trace-bound state. It should be used with TraceMemoryStatePcodeArithmetic as a means of computing the "state" of a Sleigh expression's value. It essentially works like a rudimentary taint analyzer: If any part of any input to the expression in tainted, i.e., not TraceMemoryState.KNOWN, then the result is TraceMemoryState.UNKNOWN. This is best exemplified in getUnique(long, int, Reason, PcodeStateCallbacks), though it's also exemplified in getFromSpace(AddressSpace, long, int, Reason, PcodeStateCallbacks).

NOTE: This is backed directly by the trace rather than using PcodeStateCallbacks.

Nested Class Summary

Nested classes/interfaces inherited from interface ghidra.pcode.exec.PcodeExecutorStatePiece

PcodeExecutorStatePiece.Reason

Field Summary

Fields

Modifier and Type	Field	Description
protected final PcodeTraceDataAccess	data
protected final ULongSpan.MutableULongSpanMap<TraceMemoryState>	unique

Fields inherited from class ghidra.pcode.exec.AbstractLongOffsetPcodeExecutorStatePiece

addressArithmetic, arithmetic, cb, language, uniqueSpace

Constructor Summary

Constructors

Modifier	Constructor	Description
	TraceMemoryStatePcodeExecutorStatePiece(PcodeTraceDataAccess data)	Construct a piece
protected	TraceMemoryStatePcodeExecutorStatePiece(PcodeTraceDataAccess data, ULongSpan.MutableULongSpanMap<TraceMemoryState> unique)

Method Summary

Modifier and Type	Method	Description
protected TraceMemoryState	checkSize(int size, TraceMemoryState val)	Check that the size of the value matches that given
void	clear()	Erase the entire state or piece
TraceMemoryStatePcodeExecutorStatePiece	fork(PcodeStateCallbacks cb)	Create a deep copy of this state
MemBuffer	getConcreteBuffer(Address address, PcodeArithmetic.Purpose purpose)	Bind a buffer of concrete bytes at the given start address
protected AddressSpace	getForSpace(AddressSpace space, boolean toWrite)	Get the internal space for the given address space
protected TraceMemoryState	getFromNullSpace(int size, PcodeExecutorStatePiece.Reason reason, PcodeStateCallbacks cb)	In case spaces are generated lazily, and we're reading from a space that doesn't yet exist, "read" a default value.
protected TraceMemoryState	getFromSpace(AddressSpace space, long offset, int size, PcodeExecutorStatePiece.Reason reason, PcodeStateCallbacks cb)	Get a value from the given space
Map<Register,TraceMemoryState>	getRegisterValues()	Get all register values known to this state
protected Map<Register,TraceMemoryState>	getRegisterValuesFromSpace(AddressSpace s, List<Register> registers)	Can the given space for register values, as in AbstractLongOffsetPcodeExecutorStatePiece.getRegisterValues()
protected TraceMemoryState	getUnique(long offset, int size, PcodeExecutorStatePiece.Reason reason, PcodeStateCallbacks cb)	Get a value from the unique space Some state pieces treat unique values in a way that merits a separate implementation.
protected AddressRange	range(AddressSpace space, long offset, int size)
protected void	setInSpace(AddressSpace space, long offset, int size, TraceMemoryState val, PcodeStateCallbacks cb)	Set a value in the given space
protected void	setUnique(long offset, int size, TraceMemoryState val, PcodeStateCallbacks cb)	Set a value in the unique space

Methods inherited from class ghidra.pcode.exec.AbstractLongOffsetPcodeExecutorStatePiece

forkMap, getAddressArithmetic, getArithmetic, getLanguage, getVar, getVar, getVarInternal, getVarInternal, getVarInternal, setVar, setVar, setVarInternal, setVarInternal, setVarInternal, streamPieces

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface ghidra.pcode.exec.PcodeExecutorStatePiece

checkRange, getNextEntryInternal, getNextEntryInternal, getVar, getVar, getVar, inspectBigInteger, inspectByte, inspectConcrete, inspectInt, inspectLong, inspectRegisterValue, inspectShort, quantizeOffset, setBigInteger, setByte, setConcrete, setInt, setLong, setRegisterValue, setRegisterValue, setShort, setVar, setVar, setVar

Field Details

unique

protected final ULongSpan.MutableULongSpanMap<TraceMemoryState> unique

data

protected final PcodeTraceDataAccess data

Constructor Details

TraceMemoryStatePcodeExecutorStatePiece

protected TraceMemoryStatePcodeExecutorStatePiece(PcodeTraceDataAccess data,
 ULongSpan.MutableULongSpanMap<TraceMemoryState> unique)

TraceMemoryStatePcodeExecutorStatePiece

public TraceMemoryStatePcodeExecutorStatePiece(PcodeTraceDataAccess data)

Construct a piece

Parameters:

data - the trace-data access shim

Method Details

checkSize

protected TraceMemoryState checkSize(int size,
 TraceMemoryState val)

Description copied from class: AbstractLongOffsetPcodeExecutorStatePiece

Check that the size of the value matches that given

Extensions may override this and do nothing when the abstract type has no defined size

Overrides:

checkSize in class AbstractLongOffsetPcodeExecutorStatePiece<byte[],TraceMemoryState,AddressSpace>

Parameters:

size - the size in bytes

val - the value

Returns:

the value, possibly adjusted

fork

public TraceMemoryStatePcodeExecutorStatePiece fork(PcodeStateCallbacks cb)

Description copied from interface: PcodeExecutorStatePiece

Create a deep copy of this state

Parameters:

cb - callbacks to receive emulation events

Returns:

the copy

range

protected AddressRange range(AddressSpace space,
 long offset,
 int size)

setUnique

protected void setUnique(long offset,
 int size,
 TraceMemoryState val,
 PcodeStateCallbacks cb)

Description copied from class: AbstractLongOffsetPcodeExecutorStatePiece

Set a value in the unique space

Some state pieces treat unique values in a way that merits a separate implementation. This permits the standard path to be overridden.

Overrides:

setUnique in class AbstractLongOffsetPcodeExecutorStatePiece<byte[],TraceMemoryState,AddressSpace>

Parameters:

offset - the offset in unique space to store the value

size - the number of bytes to write (the size of the value)

val - the value to store

cb - callbacks to receive emulation events

getUnique

protected TraceMemoryState getUnique(long offset,
 int size,
 PcodeExecutorStatePiece.Reason reason,
 PcodeStateCallbacks cb)

Description copied from class: AbstractLongOffsetPcodeExecutorStatePiece

Get a value from the unique space Some state pieces treat unique values in a way that merits a separate implementation. This permits the standard path to be overridden.

Overrides:

getUnique in class AbstractLongOffsetPcodeExecutorStatePiece<byte[],TraceMemoryState,AddressSpace>

Parameters:

offset - the offset in unique space to get the value

size - the number of bytes to read (the size of the value)

reason - the reason for reading state

cb - callbacks to receive emulation events

Returns:

the read value

getForSpace

protected AddressSpace getForSpace(AddressSpace space,
 boolean toWrite)

Description copied from class: AbstractLongOffsetPcodeExecutorStatePiece

Get the internal space for the given address space

Specified by:

getForSpace in class AbstractLongOffsetPcodeExecutorStatePiece<byte[],TraceMemoryState,AddressSpace>

Parameters:

space - the address space

toWrite - in case internal spaces are generated lazily, this indicates the space must be present, because it is going to be written to.

Returns:

the space, or null

setInSpace

protected void setInSpace(AddressSpace space,
 long offset,
 int size,
 TraceMemoryState val,
 PcodeStateCallbacks cb)

Description copied from class: AbstractLongOffsetPcodeExecutorStatePiece

Set a value in the given space

Specified by:

setInSpace in class AbstractLongOffsetPcodeExecutorStatePiece<byte[],TraceMemoryState,AddressSpace>

Parameters:

space - the address space

offset - the offset within the space

size - the number of bytes to write (the size of the value)

val - the value to store

cb - callbacks to receive emulation events

getFromSpace

protected TraceMemoryState getFromSpace(AddressSpace space,
 long offset,
 int size,
 PcodeExecutorStatePiece.Reason reason,
 PcodeStateCallbacks cb)

Description copied from class: AbstractLongOffsetPcodeExecutorStatePiece

Get a value from the given space

Specified by:

getFromSpace in class AbstractLongOffsetPcodeExecutorStatePiece<byte[],TraceMemoryState,AddressSpace>

Parameters:

space - the address space

offset - the offset within the space

size - the number of bytes to read (the size of the value)

reason - the reason for reading state

cb - callbacks to receive emulation events

Returns:

the read value

getFromNullSpace

protected TraceMemoryState getFromNullSpace(int size,
 PcodeExecutorStatePiece.Reason reason,
 PcodeStateCallbacks cb)

Description copied from class: AbstractLongOffsetPcodeExecutorStatePiece

In case spaces are generated lazily, and we're reading from a space that doesn't yet exist, "read" a default value.

By default, the returned value is 0, which should be reasonable for all implementations.

Overrides:

getFromNullSpace in class AbstractLongOffsetPcodeExecutorStatePiece<byte[],TraceMemoryState,AddressSpace>

Parameters:

size - the number of bytes to read (the size of the value)

reason - the reason for reading state

cb - callbacks to receive emulation events

Returns:

the default value

getRegisterValuesFromSpace

protected Map<Register,TraceMemoryState> getRegisterValuesFromSpace(AddressSpace s,
 List<Register> registers)

Description copied from class: AbstractLongOffsetPcodeExecutorStatePiece

Can the given space for register values, as in AbstractLongOffsetPcodeExecutorStatePiece.getRegisterValues()

Specified by:

getRegisterValuesFromSpace in class AbstractLongOffsetPcodeExecutorStatePiece<byte[],TraceMemoryState,AddressSpace>

Parameters:

s - the space to scan

registers - the registers known to be in the corresponding address space

Returns:

the map of registers to values

getRegisterValues

public Map<Register,TraceMemoryState> getRegisterValues()

Description copied from interface: PcodeExecutorStatePiece

Get all register values known to this state

When the state acts as a cache, it should only return those cached.

Specified by:

getRegisterValues in interface PcodeExecutorStatePiece<byte[],TraceMemoryState>

Overrides:

getRegisterValues in class AbstractLongOffsetPcodeExecutorStatePiece<byte[],TraceMemoryState,AddressSpace>

Returns:

a map of registers and their values

getConcreteBuffer

public MemBuffer getConcreteBuffer(Address address,
 PcodeArithmetic.Purpose purpose)

Description copied from interface: PcodeExecutorStatePiece

Bind a buffer of concrete bytes at the given start address

Parameters:

address - the start address

purpose - the reason why the emulator needs a concrete value

Returns:

a buffer

clear

public void clear()

Description copied from interface: PcodeExecutorStatePiece

Erase the entire state or piece

This is generally only useful when the state is itself a cache to another object. This will ensure the state is reading from that object rather than a stale cache. If this is not a cache, this could in fact clear the whole state, and the machine using it will be left in the dark.