Unintended HUGE refactoring of automotive scanners.

[polybassa]

This PR:

• changes variable names of automotive utilities to be more compliant
  with python
• adds typing for various automotive utilities
• refactors the core of automotive scanners which involve:
  • Ecu objects
  • EcuState objects
  • EcuAnsweringMachines
  • AutomotiveTestCases
  • AutomotiveTestCaseExecutors
• cleans up UDS Scanner, OBD Scanner and GMLAN Scanner

Sorry that this PR became that big. I hope it is merge-able in some way.

[guedou]

I think that it is impossible to review as it is as it introduces many changes that are different. According to the PR description, there are several different changes. Do you think that submitting them in different PR will make the whole changes easier to rewview?

[polybassa]

Unfortunately, most changes are inter-connected with each other.

Here is a little overview.

Besides renaming, I introduced breaking cleanups.

The core of this scanners are the EcuState objects. This is an object, which stores the state of an Ecu in a generic way.
In the UDS and GMLAN protocol, I've add knowledge about state changing packets. This means, I can determine, if a packet
changed the state of an Ecu.
The Ecu object relies on that EcuState to serve it's utility functions. Also the EcuAnsweringMachine uses this mechanisms of the EcuState combined with the possibility to determine state changes based on transmitted packets. This allows an EcuAnsweringMachine to mimic the behavior of a real Engine Control Unit.
To configure an EcuAnsweringMachine, I need EcuResponse objects, which allow me to describe the response behavior of an EcuAnsweringMachine based on its current EcuState.

And then... I have Scanners... :-(
Since I now have a new way to describe the internal EcuState, also the scanners were cleaned up an refactored to become much more generic by the use of less code.
A Scanner aka AutomotiveTestCaseExecutor preserves a system state Graph of EcuState objects. An AutomotiveTestCaseExecutor maintains the connection to an Ecu under test and is in charge of manipulating an Ecu in a way, that all internal AutomotiveTestCases are executed for each available EcuState in the system state Graph. AutomotiveTestCases are in charge of performing tests on a target in a certain EcuState. A test cases sends request, in my case UDS, GMLAN or OBD, to a target, and evaluates the responses. As soon as a test case determines a state change of the EcuState of the real Ecu under test, (again from the functions implemented in the protocol), it will insert a new identified EcuState into the system state Graph of the AutomotiveTestCaseExecutor.

After some tests on the old implementation, I discovered, that the implementation of the EcuState object was not flexible enough.. so I had to change this object, which ended up in a huge chain of further changes. On that way of changes, I also heavily cleaned up the code an introduced typing. This is, how I ended up with this unfortunately huge PR.

I already removed unrelated changes to that core in #3036, #3035, #3034, #3033.

Since every thing is bound to this EcuState object, in some way, it's very hard to split this PR up. I will double check, if I can remove some minor changes which are not entangled with EcuState.

[codecov]

Codecov Report

Merging #3054 (f0dc5c0) into master (7e161f1) will decrease coverage by 0.01%.
The diff coverage is 95.55%.

@@            Coverage Diff             @@
##           master    #3054      +/-   ##
==========================================
- Coverage   86.29%   86.28%   -0.02%     
==========================================
  Files         281      282       +1     
  Lines       63184    63225      +41     
==========================================
+ Hits        54522    54551      +29     
- Misses       8662     8674      +12     

Impacted Files	Coverage Δ
scapy/contrib/automotive/scanner/profiler.py	94.59% <94.59%> (ø)
scapy/contrib/automotive/scanner/executor.py	83.97% <100.00%> (-0.94%)	⬇️
scapy/contrib/automotive/scanner/graph.py	70.42% <100.00%> (-0.60%)	⬇️
scapy/contrib/automotive/gm/gmlan_scanner.py	86.08% <0.00%> (-0.79%)	⬇️
scapy/arch/windows/__init__.py	67.73% <0.00%> (-0.57%)	⬇️
scapy/sendrecv.py	80.61% <0.00%> (-0.31%)	⬇️
scapy/layers/ntp.py	84.59% <0.00%> (-0.28%)	⬇️
scapy/fields.py	91.32% <0.00%> (-0.06%)	⬇️
... and 1 more

[polybassa]

@guedou I've started a series of smaller PRs to make this one somehow merge-able.