Harden: Transparently Extending Programs at Compilation to Prevent Bugs

We have developed a variety of software hardening techniques against most of the known classes of software vulnerabilities and malicious attacks, such as race conditions, buffer underflows/overflows, null pointer exceptions, unhandled exceptions, code injection, and code-reuse attacks. However, our prior work focused on binary-only environments (i.e., post-compilation processing). While it has the advantage of broad applicability, it sacrifices efficiency and completeness due to the loss of semantic information that is present in the source code but is lost during the compilation phase. Meanwhile, the source code of many software systems, including those developed by the open-source community or used by the military, is often available. Utilizing the rich semantics of the source code can improve the efficiency and completeness of many software protection techniques. Our objective in this project is to develop new and integrate existing software protection techniques into compiler frameworks such as LLVM and GCC. We will integrate several binary-only techniques we have developed as well as several new techniques we will develop into the compiler to improve their efficiency and security.