RulePiecePathology Class Reference

Search for concatenations with unlikely things to inform return/parameter consumption calculation. More...

Inheritance diagram for RulePiecePathology:

Public Member Functions
virtual Rule *	clone (const ActionGroupList &grouplist) const
	Clone the Rule. More...
virtual void	getOpList (vector< uint4 > &oplist) const
	List of op codes this rule operates on. More...
virtual int4	applyOp (PcodeOp *op, Funcdata &data)
	Attempt to apply this Rule. More...
Public Member Functions inherited from Rule
	Rule (const string &g, uint4 fl, const string &nm)
	Construct given group, properties name. More...
bool	checkActionBreak (void)
	Check if an action breakpoint is turned on. More...
virtual void	reset (Funcdata &data)
	Reset this Rule. More...
virtual void	resetStats (void)
	Reset Rule statistics. More...
virtual void	printStatistics (ostream &s) const
	Print statistics for this Rule. More...

Static Private Member Functions
static bool	isPathology (Varnode *vn, Funcdata &data)
	Return true if concatenating with a SUBPIECE of the given Varnode is unusual. More...
static int4	tracePathologyForward (PcodeOp *op, Funcdata &data)
	Given a known pathological concatenation, trace it forward to CALLs and RETURNs. More...

Additional Inherited Members
Public Types inherited from Rule
enum	typeflags { type_disable = 1, rule_debug = 2, warnings_on = 4, warnings_given = 8 }
	Properties associated with a Rule. More...

Detailed Description

Search for concatenations with unlikely things to inform return/parameter consumption calculation.

For that can read/write part of a general purpose register, a small return value can get concatenated with unrelated data when the function writes directly to part of the return register. This searches for a characteristic pathology:

retreg = CALL();
...
retreg = CONCAT(SUBPIECE(retreg,#4),smallval);

Member Function Documentation

applyOp()

int4 RulePiecePathology::applyOp ( PcodeOp *  op, Funcdata &  data  )

virtual

Attempt to apply this Rule.

This method contains the main logic for applying the Rule. It must use a given PcodeOp as the point at which the Rule applies. If it does apply, changes are made directly to the function and 1 (non-zero) is returned, otherwise 0 is returned.

Parameters

op	is the given PcodeOp where the Rule may apply
data	is the function to which to apply

Reimplemented from Rule.

References CPUI_INDIRECT, CPUI_SUBPIECE, Funcdata::getCallSpecs(), Address::getSpace(), and AddrSpace::isBigEndian().

clone()

virtual Rule* RulePiecePathology::clone ( const ActionGroupList &  grouplist ) const

inlinevirtual

Clone the Rule.

If this Rule is a member of one of the groups in the grouplist, this returns a clone of the Rule, otherwise NULL is returned.

Parameters

grouplist

is the list of groups being cloned

Returns

the cloned Rule or NULL

Implements Rule.

References ActionGroupList::contains().

getOpList()

void RulePiecePathology::getOpList ( vector< uint4 > &  oplist ) const

virtual

List of op codes this rule operates on.

Populate the given array with all possible OpCodes this Rule might apply to. By default, this method returns all possible OpCodes

Parameters

oplist

is the array to populate

Reimplemented from Rule.

References CPUI_PIECE.

isPathology()

bool RulePiecePathology::isPathology ( Varnode *  vn, Funcdata &  data  )

staticprivate

Return true if concatenating with a SUBPIECE of the given Varnode is unusual.

Parameters

vn	is the given Varnode
data	is the function containing the Varnode

Returns

true if the configuration is a pathology

References CPUI_CALL, CPUI_CALLIND, CPUI_COPY, CPUI_INDIRECT, CPUI_MULTIEQUAL, Funcdata::getCallSpecs(), PcodeOp::getOpFromConst(), and IPTR_IOP.

tracePathologyForward()

int4 RulePiecePathology::tracePathologyForward ( PcodeOp *  op, Funcdata &  data  )

staticprivate

Given a known pathological concatenation, trace it forward to CALLs and RETURNs.

If the pathology reaches a CALL or RETURN, it is noted, through the FuncProto or FuncCallSpecs object, that the parameter or return value is only partially consumed. The subvariable flow rules can then decide whether or not to truncate this part of the data-flow.

Parameters

op	is CPUI_PIECE op that is the pathological concatenation
data	is the function containing the data-flow

Returns

a non-zero value if new bytes are labeled as unconsumed

References CPUI_CALL, CPUI_CALLIND, CPUI_COPY, CPUI_INDIRECT, CPUI_MULTIEQUAL, CPUI_RETURN, Funcdata::getCallSpecs(), FuncProto::isInputLocked(), and FuncCallSpecs::setInputBytesConsumed().

---

The documentation for this class was generated from the following files:

• ruleaction.hh
• ruleaction.cc