From d4de6f86da7f8017197d4ce6a17d02c7f0302635 Mon Sep 17 00:00:00 2001
From: Dominik Maier <domenukk@gmail.com>
Date: Wed, 28 Oct 2020 18:43:59 +0100
Subject: [PATCH] added sighandlers

---
 Cargo.toml           |  3 +-
 src/executors/mod.rs | 83 ++++++++++++++++++++++++++++++++++++++++++++
 src/utils.rs         |  2 +-
 3 files changed, 86 insertions(+), 2 deletions(-)

diff --git a/Cargo.toml b/Cargo.toml
index ee4bf652e1..574c3c8763 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -12,4 +12,5 @@ criterion = "0.3" # Benchmarking
 [dependencies]
 xxhash-rust = { version = "0.8.0-beta.4", features = ["xxh3"] } # xxh3 hashing for rust
 thiserror = "1.0" # A nicer way to write Errors
-hashbrown = "0.9" # A faster hashmap, nostd compatible
\ No newline at end of file
+hashbrown = "0.9" # A faster hashmap, nostd compatible
+libc = "0.2" # For (*nix) libc
diff --git a/src/executors/mod.rs b/src/executors/mod.rs
index e9682040a6..6e35650d88 100644
--- a/src/executors/mod.rs
+++ b/src/executors/mod.rs
@@ -38,6 +38,81 @@ pub struct InMemoryExecutor {
 
 static mut CURRENT_INMEMORY_EXECUTOR_PTR: *const InMemoryExecutor = ptr::null();
 
+#[cfg(unix)]
+pub mod unix_signals {
+
+    extern crate libc;
+    use self::libc::{c_int, c_void, sigaction, siginfo_t};
+    // Unhandled signals: SIGALRM, SIGHUP, SIGINT, SIGKILL, SIGQUIT, SIGTERM
+    use self::libc::{
+        SA_NODEFER, SA_SIGINFO, SIGABRT, SIGBUS, SIGFPE, SIGILL, SIGPIPE, SIGSEGV, SIGUSR2,
+    };
+    use std::io::{stdout, Write}; // Write brings flush() into scope
+    use std::{mem, process, ptr};
+
+    use crate::executors::CURRENT_INMEMORY_EXECUTOR_PTR;
+
+    pub extern "C" fn libaflrs_executor_inmem_handle_crash(
+        _sig: c_int,
+        info: siginfo_t,
+        _void: c_void,
+    ) {
+        unsafe {
+            if CURRENT_INMEMORY_EXECUTOR_PTR == ptr::null() {
+                println!(
+                    "We died accessing addr {}, but are not in client...",
+                    info.si_addr() as usize
+                );
+            }
+        }
+        // TODO: LLMP
+        println!("Child crashed!");
+        let _ = stdout().flush();
+    }
+
+    pub extern "C" fn libaflrs_executor_inmem_handle_timeout(
+        _sig: c_int,
+        _info: siginfo_t,
+        _void: c_void,
+    ) {
+        dbg!("TIMEOUT/SIGUSR2 received");
+        unsafe {
+            if CURRENT_INMEMORY_EXECUTOR_PTR == ptr::null() {
+                dbg!("TIMEOUT or SIGUSR2 happened, but currently not fuzzing.");
+                return;
+            }
+        }
+        // TODO: send LLMP.
+        println!("Timeout in fuzz run.");
+        let _ = stdout().flush();
+        process::abort();
+    }
+
+    pub unsafe fn setup_crash_handlers() {
+        let mut sa: sigaction = mem::zeroed();
+        libc::sigemptyset(&mut sa.sa_mask as *mut libc::sigset_t);
+        sa.sa_flags = SA_NODEFER | SA_SIGINFO;
+        sa.sa_sigaction = libaflrs_executor_inmem_handle_crash as usize;
+        for (sig, msg) in vec![
+            (SIGSEGV, "segfault"),
+            (SIGBUS, "sigbus"),
+            (SIGABRT, "sigabrt"),
+            (SIGILL, "illegal instruction"),
+            (SIGFPE, "fp exception"),
+            (SIGPIPE, "pipe"),
+        ] {
+            if sigaction(sig, &mut sa as *mut sigaction, ptr::null_mut()) < 0 {
+                panic!("Could not set up {} handler", &msg);
+            }
+        }
+
+        sa.sa_sigaction = libaflrs_executor_inmem_handle_timeout as usize;
+        if sigaction(SIGUSR2, &mut sa as *mut sigaction, ptr::null_mut()) < 0 {
+            panic!("Could not set up sigusr2 handler for timeouts");
+        }
+    }
+}
+
 impl Executor for InMemoryExecutor {
     fn run_target(&mut self) -> Result<ExitKind, AflError> {
         let bytes = match self.base.cur_input.as_ref() {
@@ -123,4 +198,12 @@ mod tests {
         in_mem_executor.add_observer(Box::new(nopserver));
         assert_eq!(in_mem_executor.post_exec_observers().is_err(), true);
     }
+
+    #[test]
+    fn test_inmem_exec() {
+        let mut in_mem_executor = InMemoryExecutor::new(test_harness_fn_nop);
+        let nopserver = Nopserver {};
+        in_mem_executor.add_observer(Box::new(nopserver));
+        assert_eq!(in_mem_executor.post_exec_observers().is_err(), true);
+    }
 }
diff --git a/src/utils.rs b/src/utils.rs
index 36da82184c..e53e4fd51e 100644
--- a/src/utils.rs
+++ b/src/utils.rs
@@ -119,6 +119,6 @@ mod tests {
         assert_eq!(next_pow2(2), 2);
         assert_eq!(next_pow2(3), 4);
         assert_eq!(next_pow2(1000), 1024);
-        assert_eq!(next_pow2(u32::MAX as u64), (u32::MAX as u64) + 1);
+        assert_eq!(next_pow2(0xFFFFFFFF as u64), (0xFFFFFFFF as u64) + 1);
     }
 }