From 4cb557039dbc6d764fa2b16f811f37e5accf2f0d Mon Sep 17 00:00:00 2001 From: JF Bastien Date: Wed, 14 Jan 2015 01:07:51 +0000 Subject: Insert random noops to increase security against ROP attacks (clang) A pass that adds random noops to X86 binaries to introduce diversity with the goal of increasing security against most return-oriented programming attacks. Command line options: -noop-insertion // Enable noop insertion. -noop-insertion-percentage=X // X% of assembly instructions will have a noop prepended (default: 50%, requires -noop-insertion) -max-noops-per-instruction=X // Randomly generate X noops per instruction. ie. roll the dice X times with probability set above (default: 1). This doesn't guarantee X noop instructions. In addition, the following 'quick switch' in clang enables basic diversity using default settings (currently: noop insertion and schedule randomization; it is intended to be extended in the future). -fdiversify This is the clang part of the patch. llvm part: D3392 http://reviews.llvm.org/D3393 Patch by Stephen Crane (@rinon) llvm-svn: 225910 --- clang/lib/Frontend/CompilerInvocation.cpp | 1 + 1 file changed, 1 insertion(+) (limited to 'clang/lib/Frontend/CompilerInvocation.cpp') diff --git a/clang/lib/Frontend/CompilerInvocation.cpp b/clang/lib/Frontend/CompilerInvocation.cpp index 0f6f01d0a08..ef8b76fa3f4 100644 --- a/clang/lib/Frontend/CompilerInvocation.cpp +++ b/clang/lib/Frontend/CompilerInvocation.cpp @@ -516,6 +516,7 @@ static bool ParseCodeGenArgs(CodeGenOptions &Opts, ArgList &Args, InputKind IK, Opts.SSPBufferSize = getLastArgIntValue(Args, OPT_stack_protector_buffer_size, 8, Diags); Opts.StackRealignment = Args.hasArg(OPT_mstackrealign); + Opts.NoopInsertion = Args.hasArg(OPT_noop_insertion); if (Arg *A = Args.getLastArg(OPT_mstack_alignment)) { StringRef Val = A->getValue(); unsigned StackAlignment = Opts.StackAlignment; -- cgit v1.2.3