Toyota: add AEB message TX checks (#820)

* Toyota: add AEB message TX checks

* misra

board/safety/safety_toyota.h

@@ -172,6 +172,15 @@ static int toyota_tx_hook(CANPacket_t *to_send) {
       }
     }
 
+    // AEB: block all actuation. only used when DSU is unplugged
+    if (addr == 0x283) {
+      // only allow the checksum, which is the last byte
+      bool block = (GET_BYTES_04(to_send) != 0U) || (GET_BYTE(to_send, 4) != 0U) || (GET_BYTE(to_send, 5) != 0U);
+      if (block) {
+        tx = 0;
+      }
+    }
+
     // LTA steering check
     // only sent to prevent dash errors, no actuation is accepted
     if (addr == 0x191) {

tests/safety/test_toyota.py

@@ -74,12 +74,23 @@ def _pcm_status_msg(self, enable):
   # Toyota gas gains are the same
   def _interceptor_msg(self, gas, addr):
     to_send = make_msg(0, addr, 6)
-    to_send[0].data[0] = (gas & 0xFF00) >> 8 
+    to_send[0].data[0] = (gas & 0xFF00) >> 8
     to_send[0].data[1] = gas & 0xFF
     to_send[0].data[2] = (gas & 0xFF00) >> 8
     to_send[0].data[3] = gas & 0xFF
     return to_send
 
+  def test_block_aeb(self):
+    for controls_allowed in (True, False):
+      for bad in (True, False):
+        for _ in range(10):
+          self.safety.set_controls_allowed(controls_allowed)
+          dat = [random.randint(1, 255) for _ in range(7)]
+          if not bad:
+            dat = [0]*6 + dat[-1:]
+          msg = common.package_can_msg([0x283, 0, bytes(dat),  0])
+          self.assertEqual(not bad, self._tx(msg))
+
   def test_accel_actuation_limits(self):
     limits = ((MIN_ACCEL, MAX_ACCEL, UNSAFE_MODE.DEFAULT),
               (MIN_ACCEL, MAX_ACCEL, UNSAFE_MODE.RAISE_LONGITUDINAL_LIMITS_TO_ISO_MAX))