Merge pull request #102 from Wenzel/expose_lief_logging_api

utils: expose function to set lief logging

Author: Wenzel

checksec/__main__.py

@@ -18,13 +18,13 @@
 from pathlib import Path
 from typing import Iterator, List, Optional, Union
 
-import lief  # only to set the lief logging level
 from docopt import docopt
 
 from .elf import ELFChecksecData, ELFSecurity, get_libc, is_elf
 from .errors import ErrorParsingFailed
 from .output import JSONOutput, RichOutput
 from .pe import PEChecksecData, PESecurity, is_pe
+from .utils import lief_set_logging
 
 
 def walk_filepath_list(filepath_list: List[Path], recursive: bool = False) -> Iterator[Path]:
@@ -76,12 +76,12 @@ def main(args):
     # logging
     formatter = "%(asctime)s %(levelname)s:%(name)s:%(message)s"
     log_lvl = logging.INFO
-    lief_logging = lief.logging.LOGGING_LEVEL.CRITICAL  # silence lief warnings
+    lief_logging = logging.CRITICAL  # silence lief warnings
     if debug:
         log_lvl = logging.DEBUG
-        lief_logging = lief.logging.LOGGING_LEVEL.DEBUG
+        lief_logging = logging.DEBUG
     logging.basicConfig(level=log_lvl, format=formatter)
-    lief.logging.set_level(lief_logging)
+    lief_set_logging(lief_logging)
 
     libc_detected = False
     # init Libc LIEF object

checksec/utils.py

@@ -5,10 +5,12 @@
 import struct
 import subprocess
 from pathlib import Path
+from typing import Dict
 
 import lddwrap
 # cannot use is_elf because of circular dependency
 import lief
+from lief.logging import LOGGING_LEVEL as lief_loglvl
 
 
 class LibcNotFoundError(Exception):
@@ -26,6 +28,14 @@ class LibcNotFoundError(Exception):
     "/lib/aarch64-linux-gnu/libc.so.6",
     "/usr/x86_64-gentoo-linux-musl/bin/ld",
 ]
+PY_LOG_TO_LIEF_LOG: Dict[int, lief_loglvl] = {
+    0: lief_loglvl.TRACE,
+    logging.DEBUG: lief_loglvl.DEBUG,
+    logging.INFO: lief_loglvl.INFO,
+    logging.WARNING: lief_loglvl.WARNING,
+    logging.ERROR: lief_loglvl.ERROR,
+    logging.CRITICAL: lief_loglvl.CRITICAL,
+}
 
 
 def find_libc():
@@ -121,3 +131,21 @@ def find_library_full(name):
     if result is None:
         raise RuntimeError("Library %s not found" % name)
     return result
+
+
+def lief_set_logging(lvl: int):
+    """Configures LIEF logging level
+
+    lvl: Python numeric logging level, corresponding to the logging module level values
+
+
+    example:
+        import logging
+        lief_set_logging(logging.WARNING)
+    """
+    try:
+        lief_log = PY_LOG_TO_LIEF_LOG[lvl]
+    except KeyError as e:
+        raise RuntimeError(f"Failed to find LIEF logging level for {lvl}") from e
+    else:
+        lief.logging.set_level(lief_log)