John the Ripper jumbo robustness improvements

by Kai Zhao for Openwall

This project aims at improving the robustness of John the Ripper jumbo, especially faced with invalid input. There are mainly two approaches, one through fuzzing, and the other through source code review. By fuzzing, American Fuzzy Lop(AFL) can be customized and integrated with John the Ripper jumbo. By source code review, manual reviews and automated static analysis such as valgrind, cppcheck and ClangStatic Analyzer can be used.