2023-12-22 12:56:54 +01:00

134 lines
4.5 KiB
Rust

// use crate::systemstate::IRQ_INPUT_BYTES_NUMBER;
use libafl::prelude::ExitKind;
use libafl::{inputs::HasTargetBytes, prelude::UsesInput};
use libafl_bolts::HasLen;
use libafl_bolts::Named;
use libafl_bolts::AsSlice;
use libafl::Error;
use libafl::observers::Observer;
use hashbrown::HashMap;
use serde::{Deserialize, Serialize};
use super::{
CURRENT_SYSTEMSTATE_VEC,
RawFreeRTOSSystemState,
RefinedTCB,
RefinedFreeRTOSSystemState,
freertos::{List_t, TCB_t, rtos_struct, rtos_struct::*},
};
//============================= Observer
/// The Qemusystemstate Observer retrieves the systemstate
/// that will get updated by the target.
#[derive(Serialize, Deserialize, Debug, Default)]
#[allow(clippy::unsafe_derive_deserialize)]
pub struct QemuSystemStateObserver
{
pub last_run: Vec<RefinedFreeRTOSSystemState>,
pub last_input: Vec<u8>,
name: String,
}
impl<S> Observer<S> for QemuSystemStateObserver
where
S: UsesInput,
S::Input : HasTargetBytes,
{
#[inline]
fn pre_exec(&mut self, _state: &mut S, _input: &S::Input) -> Result<(), Error> {
unsafe {CURRENT_SYSTEMSTATE_VEC.clear(); }
Ok(())
}
#[inline]
fn post_exec(&mut self, _state: &mut S, _input: &S::Input, _exit_kind: &ExitKind) -> Result<(), Error> {
unsafe {self.last_run = refine_system_states(&mut CURRENT_SYSTEMSTATE_VEC);}
self.last_input=_input.target_bytes().as_slice().to_owned();
Ok(())
}
}
impl Named for QemuSystemStateObserver
{
#[inline]
fn name(&self) -> &str {
self.name.as_str()
}
}
impl HasLen for QemuSystemStateObserver
{
#[inline]
fn len(&self) -> usize {
self.last_run.len()
}
}
impl QemuSystemStateObserver {
pub fn new() -> Self {
Self{last_run: vec![], last_input: vec![], name: "systemstate".to_string()}
}
}
//============================= Parsing helpers
/// Parse a List_t containing TCB_t into Vec<TCB_t> from cache. Consumes the elements from cache
fn tcb_list_to_vec_cached(list: List_t, dump: &mut HashMap<u32,rtos_struct>) -> Vec<TCB_t>
{
let mut ret : Vec<TCB_t> = Vec::new();
if list.uxNumberOfItems == 0 {return ret;}
let last_list_item = match dump.remove(&list.pxIndex).expect("List_t entry was not in Hashmap") {
List_Item_struct(li) => li,
List_MiniItem_struct(mli) => match dump.remove(&mli.pxNext).expect("MiniListItem pointer invaild") {
List_Item_struct(li) => li,
_ => panic!("MiniListItem of a non empty List does not point to ListItem"),
},
_ => panic!("List_t entry was not a ListItem"),
};
let mut next_index = last_list_item.pxNext;
let last_tcb = match dump.remove(&last_list_item.pvOwner).expect("ListItem Owner not in Hashmap") {
TCB_struct(t) => t,
_ => panic!("List content does not equal type"),
};
for _ in 0..list.uxNumberOfItems-1 {
let next_list_item = match dump.remove(&next_index).expect("List_t entry was not in Hashmap") {
List_Item_struct(li) => li,
List_MiniItem_struct(mli) => match dump.remove(&mli.pxNext).expect("MiniListItem pointer invaild") {
List_Item_struct(li) => li,
_ => panic!("MiniListItem of a non empty List does not point to ListItem"),
},
_ => panic!("List_t entry was not a ListItem"),
};
match dump.remove(&next_list_item.pvOwner).expect("ListItem Owner not in Hashmap") {
TCB_struct(t) => {ret.push(t)},
_ => panic!("List content does not equal type"),
}
next_index=next_list_item.pxNext;
}
ret.push(last_tcb);
ret
}
/// Drains a List of raw SystemStates to produce a refined trace
fn refine_system_states(input: &mut Vec<RawFreeRTOSSystemState>) -> Vec<RefinedFreeRTOSSystemState> {
let mut ret = Vec::<RefinedFreeRTOSSystemState>::new();
let mut start_tick : u64 = 0;
for mut i in input.drain(..) {
let mut collector = Vec::<RefinedTCB>::new();
for j in i.prio_ready_lists.into_iter().rev() {
let mut tmp = tcb_list_to_vec_cached(j,&mut i.dumping_ground).iter().map(|x| RefinedTCB::from_tcb(x)).collect();
collector.append(&mut tmp);
}
ret.push(RefinedFreeRTOSSystemState {
current_task: RefinedTCB::from_tcb_owned(i.current_tcb),
start_tick: start_tick,
end_tick: i.qemu_tick,
ready_list_after: collector,
input_counter: i.input_counter,//+IRQ_INPUT_BYTES_NUMBER,
last_pc: i.last_pc,
});
start_tick=i.qemu_tick;
}
return ret;
}