diff --git a/.gitignore b/.gitignore
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--- /dev/null
+++ b/.gitignore
@@ -0,0 +1 @@
+taosc
diff --git a/COPYING b/COPYING
new file mode 100644
index 0000000..be3f7b2
--- /dev/null
+++ b/COPYING
@@ -0,0 +1,661 @@
+ GNU AFFERO GENERAL PUBLIC LICENSE
+ Version 3, 19 November 2007
+
+ Copyright (C) 2007 Free Software Foundation, Inc. <https://fsf.org/>
+ Everyone is permitted to copy and distribute verbatim copies
+ of this license document, but changing it is not allowed.
+
+ Preamble
+
+ The GNU Affero General Public License is a free, copyleft license for
+software and other kinds of works, specifically designed to ensure
+cooperation with the community in the case of network server software.
+
+ The licenses for most software and other practical works are designed
+to take away your freedom to share and change the works. By contrast,
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+share and change all versions of a program--to make sure it remains free
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+
+ When we speak of free software, we are referring to freedom, not
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+ Developers that use our General Public Licenses protect your rights
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+ A secondary benefit of defending all users' freedom is that
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+ An older license, called the Affero General Public License and
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+
+ If the disclaimer of warranty and limitation of liability provided
+above cannot be given local legal effect according to their terms,
+reviewing courts shall apply local law that most closely approximates
+an absolute waiver of all civil liability in connection with the
+Program, unless a warranty or assumption of liability accompanies a
+copy of the Program in return for a fee.
+
+ END OF TERMS AND CONDITIONS
+
+ How to Apply These Terms to Your New Programs
+
+ If you develop a new program, and you want it to be of the greatest
+possible use to the public, the best way to achieve this is to make it
+free software which everyone can redistribute and change under these terms.
+
+ To do so, attach the following notices to the program. It is safest
+to attach them to the start of each source file to most effectively
+state the exclusion of warranty; and each file should have at least
+the "copyright" line and a pointer to where the full notice is found.
+
+ <one line to give the program's name and a brief idea of what it does.>
+ Copyright (C) <year> <name of author>
+
+ This program is free software: you can redistribute it and/or modify
+ it under the terms of the GNU Affero General Public License as published by
+ the Free Software Foundation, either version 3 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU Affero General Public License for more details.
+
+ You should have received a copy of the GNU Affero General Public License
+ along with this program. If not, see <https://www.gnu.org/licenses/>.
+
+Also add information on how to contact you by electronic and paper mail.
+
+ If your software can interact with users remotely through a computer
+network, you should also make sure that it provides a way for users to
+get its source. For example, if your program is a web application, its
+interface could display a "Source" link that leads users to an archive
+of the code. There are many ways you could offer source, and different
+solutions will be better for different programs; see section 13 for the
+specific requirements.
+
+ You should also get your employer (if you work as a programmer) or school,
+if any, to sign a "copyright disclaimer" for the program, if necessary.
+For more information on this, and how to apply and follow the GNU AGPL, see
+<https://www.gnu.org/licenses/>.
diff --git a/Makefile b/Makefile
new file mode 100644
index 0000000..d768151
--- /dev/null
+++ b/Makefile
@@ -0,0 +1,8 @@
+CXXFLAGS += -std=c++20
+LDFLAGS += -lcommon -linstructionAPI -lparseAPI # dyninst
+
+.PHONY: all clean
+all: taosc
+
+clean:
+ rm taosc
diff --git a/taosc.cc b/taosc.cc
new file mode 100644
index 0000000..857fcf5
--- /dev/null
+++ b/taosc.cc
@@ -0,0 +1,279 @@
+// Slicing-based binary fault localizer and patch searcher
+// Copyright (C) 2024 Nguyễn Gia Phong
+//
+// This file is part of taosc.
+//
+// Taosc is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Affero General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Taosc is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Affero General Public License for more details.
+//
+// You should have received a copy of the GNU Affero General Public License
+// along with taosc. If not, see <https://www.gnu.org/licenses/>.
+
+// Dyninst headers
+#include <CFG.h>
+#include <CodeObject.h>
+#include <Graph.h>
+#include <Instruction.h>
+#include <InstructionDecoder.h>
+#include <slicing.h>
+
+using AbstractRegion = Dyninst::AbsRegion;
+using Address = Dyninst::Address;
+using AssignmentConverter = Dyninst::AssignmentConverter;
+using AssignmentPtr = Dyninst::Assignment::Ptr;
+using Block = Dyninst::ParseAPI::Block;
+using CodeObject = Dyninst::ParseAPI::CodeObject;
+using CodeRegion = Dyninst::ParseAPI::CodeRegion;
+using CodeSource = Dyninst::ParseAPI::SymtabCodeSource;
+using Edge = Dyninst::Edge;
+using EdgeIterator = Dyninst::EdgeIterator;
+using Function = Dyninst::ParseAPI::Function;
+using Graph = Dyninst::Graph;
+using Instruction = Dyninst::InstructionAPI::Instruction;
+using InstructionDecoder = Dyninst::InstructionAPI::InstructionDecoder;
+using InstructionCategory = Dyninst::InstructionAPI::InsnCategory;
+using NodeIterator = Dyninst::NodeIterator;
+using SliceNode = Dyninst::SliceNode;
+using Slicer = Dyninst::Slicer;
+
+#include <cassert>
+#include <functional>
+#include <iostream>
+#include <map>
+#include <queue>
+
+class SearchingAll : public Slicer::Predicates
+ {
+ public:
+ std::vector <Function*>
+ followCallBackward (Block* caller,
+ CallStack_t& call_stack,
+ AbstractRegion argument) override
+ {
+ std::vector <Function*> callers;
+ caller->getFuncs (callers);
+ return callers;
+ }
+ };
+
+template <class Element, class Iterator>
+ std::vector <Element*>
+ sorted (auto iter)
+ {
+ Iterator begin, end;
+ std::vector <Element*> result;
+ for (iter (begin, end); begin != end; ++begin)
+ result.push_back (static_cast <Element*> ((*begin).get ()));
+ return result;
+ }
+
+template <class SlicerPredicates>
+ class SlicerHelper
+ {
+ CodeSource& cs;
+ InstructionDecoder decoder;
+ SlicerPredicates predicates;
+ AssignmentConverter ac {true, true};
+ std::set <Address> seen;
+ std::vector <std::vector <Address>> bfs_slices;
+
+ public:
+ SlicerHelper (CodeSource& cs)
+ : cs {cs},
+ decoder {(const void*) nullptr, 1, cs.getArch ()},
+ ac {true, true} // enable caching and stack analysis
+ {
+ this->predicates.setSearchForControlFlowDep(true);
+ }
+
+ Instruction
+ decode (Address addr)
+ {
+ auto const& insn = this->decoder.decode ((const unsigned char *)
+ this->cs.getPtrToInstruction (addr));
+ assert (insn.size () > 0);
+ return insn;
+ }
+
+#define ITER(i, E, I, x, f) \
+ for (auto const& i : sorted <E, I> ([x] (auto& b, auto& e) { x->f (b, e); }))
+
+ void
+ slice (Instruction const& insn, Address addr, Function* fun, Block* blk)
+ {
+ std::vector <AssignmentPtr> assignments;
+ this->ac.convert (insn, addr, fun, blk, assignments);
+ if (assignments.empty ())
+ return;
+ for (auto const& asgn : assignments)
+ {
+ this->bfs_slices.emplace_back ();
+ Slicer s {asgn, blk, fun};
+ auto const& slice = s.backwardSlice (this->predicates);
+ ITER (node, SliceNode, NodeIterator, slice, exitNodes)
+ {
+ this->seen.insert (node->addr ());
+ std::queue <SliceNode*> q; // breadth-first traversal
+ q.push (node);
+ while (!q.empty ())
+ {
+ auto const& parent = q.front ();
+ q.pop ();
+ this->bfs_slices.back ().push_back (parent->addr ());
+ ITER (edge, Edge, EdgeIterator, parent, ins)
+ {
+ auto const& child = edge->source ();
+ if (this->seen.count (child->addr ()) > 0)
+ continue;
+ this->seen.insert (child->addr ());
+ q.push (static_cast <SliceNode*> (child.get ()));
+ }
+ }
+ }
+ }
+ }
+
+#undef ITER
+
+ std::vector <Address>
+ slice_zip ()
+ {
+ std::vector <Address> result;
+ size_t n = 0;
+ for (auto const& v : this->bfs_slices)
+ {
+ if (result.empty () || v[0] != result.back ())
+ result.push_back (v[0]);
+ n = std::max (n, v.size ());
+ }
+ for (size_t i = 1; i < n; ++i)
+ for (auto const& v : this->bfs_slices)
+ if (i < v.size ())
+ result.push_back (v[i]);
+ return result;
+ }
+ };
+
+Block*
+next_block (CodeObject& co, CodeRegion* region, Address address)
+{
+ auto blk = co.findBlockByEntry (region, address);
+ if (blk != nullptr)
+ return blk;
+ co.parse (address, true);
+ blk = co.findBlockByEntry (region, address);
+ return (blk != nullptr) ? blk : co.findNextBlock (region, address);
+}
+
+Block*
+find_block (CodeSource& cs, CodeObject& co, Address target_addr)
+{
+ if (!cs.isCode (target_addr))
+ {
+ std::cerr << std::hex << target_addr
+ << " does not point to an instruction\n";
+ return nullptr;
+ }
+ std::set <CodeRegion*> regions;
+ cs.findRegions (target_addr, regions);
+ if (regions.size () != 1)
+ {
+ std::cerr << "expected 1 region containing instruction, found "
+ << regions.size () << '\n';
+ return nullptr;
+ }
+ for (auto const& region : regions)
+ {
+ std::set <Block*> blocks;
+ co.findBlocks (region, target_addr, blocks);
+ if (blocks.size () == 1)
+ for (auto const& blk : blocks)
+ return blk;
+
+ auto blk = next_block (co, region, region->low ());
+ while (blk != nullptr && target_addr > blk->last ())
+ blk = next_block (co, region, blk->end ());
+ if (blk == nullptr)
+ return nullptr;
+ assert (target_addr >= blk->start () && target_addr < blk->end ());
+ return blk;
+ }
+ // std::unreachable();
+ return nullptr;
+}
+
+std::vector <Address> const
+patch_locations (CodeSource& cs,
+ std::vector<Function*> const& functions,
+ Block* block,
+ Address target_addr)
+{
+ SlicerHelper <SearchingAll> helper {cs};
+ std::map <Address, std::string> locations;
+ for (auto const& fun : functions)
+ helper.slice (helper.decode (target_addr), target_addr, fun, block);
+ return helper.slice_zip ();
+}
+
+std::vector <Address> const
+return_values (CodeSource& cs,
+ std::vector<Function*> const& functions,
+ Block* block,
+ Address target_addr)
+{
+ SlicerHelper <Slicer::Predicates> helper {cs};
+ for (auto const& fun : functions)
+ for (auto const& blk : fun->blocks ())
+ for (auto [addr, step] = std::tuple {blk->start (), 0ul};
+ addr < blk->end ();
+ addr += step)
+ {
+ auto const& insn = helper.decode (addr);
+ step = insn.size ();
+ if (insn.getCategory () == InstructionCategory::c_ReturnInsn)
+ helper.slice (insn, addr, fun, blk);
+ }
+ return helper.slice_zip ();
+}
+
+int
+main (int argc, char** argv)
+{
+ if (argc != 3)
+ {
+ std::cerr << "Usage: " << argv[0]
+ << " <binary path> <instruction address>\n";
+ return -1;
+ }
+ CodeSource cs {argv[1]};
+ Address target_addr;
+ {
+ std::stringstream ss;
+ ss << std::hex << argv[2];
+ ss >> target_addr;
+ }
+ CodeObject co {&cs};
+ co.parse (); // parsed functions have same lifetime as co
+ auto const& block = find_block (cs, co, target_addr);
+ if (block == nullptr)
+ {
+ std::cerr << "block containing instruction not found\n";
+ return -1;
+ }
+ std::vector<Function*> functions;
+ block->getFuncs (functions);
+
+ for (auto const& addr : patch_locations (cs, functions, block, target_addr))
+ std::cout << std::hex << addr << '\n';
+ std::cout << "------\n";
+ for (auto const& addr : return_values (cs, functions, block, target_addr))
+ std::cout << std::hex << addr << '\n';
+ return 0;
+}
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