import binascii
import contextlib
import base62
from credsweeper.common.constants import ASCII
from credsweeper.config import Config
from credsweeper.credentials import LineData
from credsweeper.file_handler.analysis_target import AnalysisTarget
from credsweeper.filters import Filter
[docs]class ValueGitHubCheck(Filter):
"""GitHub Classic Token validation"""
def __init__(self, config: Config = None) -> None:
pass
[docs] def run(self, line_data: LineData, target: AnalysisTarget) -> bool:
"""Run filter checks on received token which might be structured.
Args:
line_data: credential candidate data
target: multiline target from which line data was obtained
Return:
True, when need to filter candidate and False if left
"""
# https://github.blog/2021-04-05-behind-githubs-new-authentication-token-formats/
with contextlib.suppress(Exception):
if line_data.value.startswith("gh") and '_' == line_data.value[3]:
token = line_data.value[4:-6]
data = token.encode(ASCII, errors="strict")
crc32sum = binascii.crc32(data)
base62_crc32 = line_data.value[-6:]
sign_b = base62.decodebytes(base62_crc32)
crc32sign = int.from_bytes(sign_b, "big")
if crc32sign == crc32sum:
return False
return True