Initial commit of a fuzzer for Meshtastic (#5790)

* Initial commit of a fuzzer for Meshtastic.

* Use a max of 5 for the phone queues

* Only write files to the temp dir

* Limitless queue + fuzzer = lots of ram :)

* Use $PIO_ENV for path to program

* spelling: s/is/to/

* Use loopCanSleep instead of a lock in Router

* realHardware allows full use of a CPU core

* Ignore checkov CKV_DOCKER_2 & CKV_DOCKER_3

* Add Atak seed

* Fix lint issues in build.sh

* Use exception to exit from portduino_main

* Separate build & source files into $WORK & $SRC

* Use an ephemeral port for the API server

* Include CXXFLAGS in the link step

* Read all shared libraries

* Use a separate work directory for each sanitizer

---------

Co-authored-by: Ben Meadors <benmmeadors@gmail.com>

.clusterfuzzlite/platformio-clusterfuzzlite-post.py

@@ -0,0 +1,35 @@
+"""PlatformIO build script (post: runs after other Meshtastic scripts)."""
+
+import os
+import shlex
+
+from SCons.Script import DefaultEnvironment
+
+env = DefaultEnvironment()
+
+# Remove any static libraries from the LIBS environment. Static libraries are
+# handled in platformio-clusterfuzzlite-pre.py.
+static_libs = set(lib[2:] for lib in shlex.split(os.getenv("STATIC_LIBS")))
+env.Replace(
+    LIBS=[
+        lib for lib in env["LIBS"] if not (isinstance(lib, str) and lib in static_libs)
+    ],
+)
+
+# FrameworkArduino/portduino/main.cpp contains the "main" function the binary.
+# The fuzzing framework also provides a "main" function and needs to be run
+# before Meshtastic is started. We rename the "main" function for Meshtastic to
+# "portduino_main" here so that it can be called inside the fuzzer.
+env.AddPostAction(
+    "$BUILD_DIR/FrameworkArduino/portduino/main.cpp.o",
+    env.VerboseAction(
+        " ".join(
+            [
+                "$OBJCOPY",
+                "--redefine-sym=main=portduino_main",
+                "$BUILD_DIR/FrameworkArduino/portduino/main.cpp.o",
+            ]
+        ),
+        "Renaming main symbol to portduino_main",
+    ),
+)