Purpose

This tool does check compiled elf-files (and all dependencies) against given rules. Objectives are

• check for discouraged functions (e.g. strcpy)
• check for combinations of symbols (e.g. mutex and pthreads)

Usage

usage: pysymbolcheck [-h] [--libpath LIBPATH] rules file

Eval symbols of a binary against given rules

positional arguments:
  rules              Path to a rule file
  file               File to parse

optional arguments:
  -h, --help         show this help message and exit
  --libpath LIBPATH  ":" separated path to lookup libraries

Rule file format

a rule file consists of a json-array, like this

[]

within this n element of the following can be added

{ "severity": "error", "id": "A_Unique_ID", "msg": "some message", "rule", "<rule>" }

for severity it is advised to use only info, warning or error

Rule definition

A rule can consist of any logical combined operation such as

((A && B) || (C && D )) && !E

to get the needed information following keywords are implemented

keyword	variables	purpose	example
AVAILABLE()	symbol-name	check if a symbol is defined in the binary or any referenced lib	AVAILABLE(strncpy)
USED()	symbol-name	check if a symbol is used by some binary or lib	USED(strncpy)
SIZE()	symbol-name	get the size in bytes of a symbol	SIZE(strncpy)
TYPE()	symbol-name	get the type in bytes of a symbol	TYPE(strncpy)
&&	n.a.	logical and	A && B
||	n.a.	logical or	A || B
!	n.a.	not operator	!A