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Code Issues Releases Wiki Activity

Use InjectPayload for segment ops

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This commit is contained in:
caheckman 2019-08-29 14:17:02 -04:00
parent 06de0d46a0
commit 4c3289f09f
7 changed files with 93 additions and 132 deletions
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82
Ghidra/Features/Decompiler/src/decompile/cpp/userop.cc
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@ -124,31 +124,6 @@ SegmentOp::SegmentOp(Architecture *g,const string &nm,int4 ind)
constresolve.space = (AddrSpace *)0;
}
/// \brief Execute a stream of operations (OpFollow) given a starting input value
///
/// Each operation is performed in turn, with output from the previous becoming
/// input of the next. The final output is returned.
/// \param follow is the ordered set of operations to perform
/// \param input is the constant input for the first operation
/// \return the final constant output
uintb SegmentOp::executeSide(const vector<OpFollow> &follow,uintb input)
{
for(int4 i=0;i<follow.size();++i) {
switch(follow[i].opc) {
case CPUI_INT_AND:
input &= follow[i].val;
break;
case CPUI_INT_LEFT:
input <<= follow[i].val;
break;
default:
break;
}
}
return input;
}
bool SegmentOp::unify(Funcdata &data,PcodeOp *op,
vector<Varnode *> &bindlist) const
{
@ -163,7 +138,7 @@ bool SegmentOp::unify(Funcdata &data,PcodeOp *op,
if (op->getIn(0)->getOffset() != useropindex) return false;
if (op->numInput() != 3) return false;
innervn = op->getIn(1);
if (basepresent) {
if (baseinsize != 0) {
basevn = op->getIn(1);
innervn = op->getIn(2);
if (basevn->isConstant())
@ -181,40 +156,23 @@ bool SegmentOp::unify(Funcdata &data,PcodeOp *op,
uintb SegmentOp::execute(const vector<uintb> &input) const
{
uintb base,inner;
if (basepresent)
base = executeSide(basefollow,input[1]);
else
base = 0;
inner = executeSide(innerfollow,input[0]);
return (base+inner);
ExecutablePcode *pcodeScript = (ExecutablePcode *)glb->pcodeinjectlib->getPayload(injectId);
return pcodeScript->evaluate(input);
}
void SegmentOp::restoreXml(const Element *el)
{
spc = glb->getSpaceByName(el->getAttributeValue("space"));
injectId = -1;
baseinsize = 0;
innerinsize = 0;
bool userdefined = false;
forcesegment = true;
supportsfarpointer = false;
name = "segment"; // Default name, might be overridden by userop attribute
for(int4 i=0;i<el->getNumAttributes();++i) {
const string &nm(el->getAttributeName(i));
if (nm == "space") continue;
else if (nm == "baseinsize") {
istringstream s(el->getAttributeValue(i));
s.unsetf(ios::dec | ios::hex | ios::oct);
s >> baseinsize;
}
else if (nm == "innerinsize") {
istringstream s1(el->getAttributeValue(i));
s1.unsetf(ios::dec | ios::hex | ios::oct);
s1 >> innerinsize;
}
else if (nm == "farpointer")
supportsfarpointer = true;
else if (nm == "userop") { // Based on existing sleigh op
@ -227,28 +185,17 @@ void SegmentOp::restoreXml(const Element *el)
throw LowlevelError("Redefining userop "+name);
}
}
else if (nm == "force")
forcesegment = xml_readbool(el->getAttributeValue(i));
else
throw LowlevelError("Bad segmentop tag attribute: "+nm);
}
if (!userdefined)
throw LowlevelError("Missing userop attribute in segmentop tag");
basepresent = (baseinsize != 0);
const List &list(el->getChildren());
List::const_iterator iter;
for(iter=list.begin();iter!=list.end();++iter) {
const Element *subel = *iter;
if (subel->getName()=="baseop") {
basefollow.push_back(OpFollow());
basefollow.back().restoreXml(subel);
}
else if (subel->getName()=="innerop") {
innerfollow.push_back(OpFollow());
innerfollow.back().restoreXml(subel);
}
else if (subel->getName()=="constresolve") {
if (subel->getName()=="constresolve") {
int4 sz;
const List &sublist(subel->getChildren());
if (!sublist.empty()) {
@ -260,9 +207,28 @@ void SegmentOp::restoreXml(const Element *el)
constresolve.size = sz;
}
}
else if (subel->getName() == "pcode") {
string nm = name + "_pcode";
string source = "cspec";
injectId = glb->pcodeinjectlib->restoreXmlInject(source, nm, InjectPayload::EXECUTABLEPCODE_TYPE, subel);
}
else
throw LowlevelError("Bad segment pattern tag: "+subel->getName());
}
if (injectId < 0)
throw LowlevelError("Missing <execute> child in <segmentop> tag");
InjectPayload *payload = glb->pcodeinjectlib->getPayload(injectId);
if (payload->sizeOutput() != 1)
throw LowlevelError("<execute> child of <segmentop> tag must declare one <output>");
if (payload->sizeInput() == 1) {
innerinsize = payload->getInput(0).getSize();
}
else if (payload->sizeInput() == 2) {
baseinsize = payload->getInput(0).getSize();
innerinsize = payload->getInput(1).getSize();
}
else
throw LowlevelError("<execute> child of <segmentop> tag must declare one or two <input> tags");
}
/// \param g is the Architecture owning this set of jump assist scripts