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#include <qpdf/QPDF.hh>
#include <qpdf/QPDFWriter.hh>
#include <qpdf/QUtil.hh>
#include <qpdf/BufferInputSource.hh>
#include <qpdf/Buffer.hh>
#include <qpdf/Pl_Discard.hh>
#include <qpdf/QPDFPageDocumentHelper.hh>
#include <qpdf/QPDFPageObjectHelper.hh>
#include <qpdf/QPDFPageLabelDocumentHelper.hh>
#include <qpdf/QPDFOutlineDocumentHelper.hh>
#include <qpdf/QPDFAcroFormDocumentHelper.hh>
#include <cstdlib>
class DiscardContents: public QPDFObjectHandle::ParserCallbacks
{
public:
virtual ~DiscardContents() {}
virtual void handleObject(QPDFObjectHandle) {}
virtual void handleEOF() {}
};
class FuzzHelper
{
public:
FuzzHelper(unsigned char const* data, size_t size);
void run();
private:
PointerHolder<QPDF> getQpdf();
PointerHolder<QPDFWriter> getWriter(PointerHolder<QPDF>);
void doWrite(PointerHolder<QPDFWriter> w);
void testWrite();
void testPages();
void testOutlines();
void doChecks();
Buffer input_buffer;
Pl_Discard discard;
};
FuzzHelper::FuzzHelper(unsigned char const* data, size_t size) :
// We do not modify data, so it is safe to remove the const for Buffer
input_buffer(const_cast<unsigned char*>(data), size)
{
}
PointerHolder<QPDF>
FuzzHelper::getQpdf()
{
PointerHolder<InputSource> is =
new BufferInputSource("fuzz input", &this->input_buffer);
PointerHolder<QPDF> qpdf = new QPDF();
qpdf->processInputSource(is);
return qpdf;
}
PointerHolder<QPDFWriter>
FuzzHelper::getWriter(PointerHolder<QPDF> qpdf)
{
PointerHolder<QPDFWriter> w = new QPDFWriter(*qpdf);
w->setOutputPipeline(&this->discard);
w->setDecodeLevel(qpdf_dl_all);
return w;
}
void
FuzzHelper::doWrite(PointerHolder<QPDFWriter> w)
{
try
{
w->write();
}
catch (QPDFExc const& e)
{
std::cerr << e.what() << std::endl;
}
catch (std::runtime_error const& e)
{
std::cerr << e.what() << std::endl;
}
}
void
FuzzHelper::testWrite()
{
// Write in various ways to exercise QPDFWriter
PointerHolder<QPDF> q;
PointerHolder<QPDFWriter> w;
q = getQpdf();
w = getWriter(q);
w->setDeterministicID(true);
w->setQDFMode(true);
doWrite(w);
q = getQpdf();
w = getWriter(q);
w->setStaticID(true);
w->setLinearization(true);
w->setR6EncryptionParameters(
"u", "o", true, true, true, true, true, true, qpdf_r3p_full, true);
doWrite(w);
q = getQpdf();
w = getWriter(q);
w->setStaticID(true);
w->setObjectStreamMode(qpdf_o_disable);
w->setR3EncryptionParameters(
"u", "o", true, true, true, true, true, true, qpdf_r3p_full);
doWrite(w);
q = getQpdf();
w = getWriter(q);
w->setDeterministicID(true);
w->setObjectStreamMode(qpdf_o_generate);
w->setLinearization(true);
doWrite(w);
}
void
FuzzHelper::testPages()
{
// Parse all content streams, and exercise some helpers that
// operate on pages.
PointerHolder<QPDF> q = getQpdf();
QPDFPageDocumentHelper pdh(*q);
QPDFPageLabelDocumentHelper pldh(*q);
QPDFOutlineDocumentHelper odh(*q);
QPDFAcroFormDocumentHelper afdh(*q);
afdh.generateAppearancesIfNeeded();
pdh.flattenAnnotations();
std::vector<QPDFPageObjectHelper> pages = pdh.getAllPages();
DiscardContents discard_contents;
int pageno = 0;
for (std::vector<QPDFPageObjectHelper>::iterator iter =
pages.begin();
iter != pages.end(); ++iter)
{
QPDFPageObjectHelper& page(*iter);
++pageno;
try
{
page.coalesceContentStreams();
page.parseContents(&discard_contents);
page.getImages();
pldh.getLabelForPage(pageno);
QPDFObjectHandle page_obj(page.getObjectHandle());
page_obj.getJSON(true).unparse();
odh.getOutlinesForPage(page_obj.getObjGen());
std::vector<QPDFAnnotationObjectHelper> annotations =
afdh.getWidgetAnnotationsForPage(page);
for (std::vector<QPDFAnnotationObjectHelper>::iterator annot_iter =
annotations.begin();
annot_iter != annotations.end(); ++annot_iter)
{
QPDFAnnotationObjectHelper& aoh = *annot_iter;
afdh.getFieldForAnnotation(aoh);
}
}
catch (QPDFExc& e)
{
std::cerr << "page " << pageno << ": "
<< e.what() << std::endl;
}
}
}
void
FuzzHelper::testOutlines()
{
PointerHolder<QPDF> q = getQpdf();
std::list<std::vector<QPDFOutlineObjectHelper> > queue;
QPDFOutlineDocumentHelper odh(*q);
queue.push_back(odh.getTopLevelOutlines());
while (! queue.empty())
{
std::vector<QPDFOutlineObjectHelper>& outlines = *(queue.begin());
for (std::vector<QPDFOutlineObjectHelper>::iterator iter =
outlines.begin();
iter != outlines.end(); ++iter)
{
QPDFOutlineObjectHelper& ol = *iter;
ol.getDestPage();
queue.push_back(ol.getKids());
}
queue.pop_front();
}
}
void
FuzzHelper::doChecks()
{
// Get as much coverage as possible in parts of the library that
// might benefit from fuzzing.
testWrite();
testPages();
testOutlines();
}
void
FuzzHelper::run()
{
// The goal here is that you should be able to throw anything at
// libqpdf and it will respond without any memory errors and never
// do anything worse than throwing a QPDFExc or
// std::runtime_error. Throwing any other kind of exception,
// segfaulting, or having a memory error (when built with
// appropriate sanitizers) will all cause abnormal exit.
try
{
doChecks();
}
catch (QPDFExc const& e)
{
std::cerr << "QPDFExc: " << e.what() << std::endl;
}
catch (std::runtime_error const& e)
{
std::cerr << "runtime_error: " << e.what() << std::endl;
}
}
extern "C" int LLVMFuzzerTestOneInput(unsigned char const* data, size_t size)
{
#ifndef _WIN32
// Used by jpeg library to work around false positives in memory
// sanitizer.
setenv("JSIMD_FORCENONE", "1", 1);
#endif
FuzzHelper f(data, size);
f.run();
return 0;
}
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