"""Onionr - Private P2P Communication.

Prevent eval/exec/os.system and log it
"""
import base64
from os import read

import logger
from utils import identifyhome
from onionrexceptions import ArbitraryCodeExec
from utils import readstatic
"""
    This program is free software: you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation, either version 3 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program.  If not, see <https://www.gnu.org/licenses/>.
"""


def block_system(cmd):
    """Prevent os.system except for whitelisted commands+contexts."""
    logger.warn('POSSIBLE EXPLOIT DETECTED, SEE LOGS', terminal=True)
    logger.warn(f'POSSIBLE EXPLOIT: shell command not in whitelist: {cmd}')
    raise ArbitraryCodeExec('os.system command not in whitelist')


def block_exec(event, info):
    """Prevent arbitrary code execution in eval/exec and log it."""
    # because libraries have stupid amounts of compile/exec/eval,
    # We have to use a whitelist where it can be tolerated
    # Generally better than nothing, not a silver bullet
    return
    whitelisted_code = [
                        'netrc.py',
                        'shlex.py',
                        'gzip.py',
                        '<werkzeug routing>',
                        'werkzeug/test.py',
                        'multiprocessing/popen_fork.py',
                        'multiprocessing/util.py',
                        'multiprocessing/connection.py',
                        'multiprocessing/queues.py',
                        'multiprocessing/synchronize.py',
                        'onionrutils/escapeansi.py',
                        'stem/connection.py',
                        'stem/response/add_onion.py',
                        'stem/response/authchallenge.py',
                        'stem/response/getinfo.py',
                        'stem/response/getconf.py',
                        'stem/response/mapaddress.py',
                        'stem/response/protocolinfo.py',
                        'apport/__init__.py',
                        'apport/report.py',
                        'gevent/pool.py',
                        'gevent/queue.py',
                        'gevent/lock.py',
                        'gevent/monkey.py',
                        'gevent/_semaphore.py',
                        'gevent/_imap.py'
                       ]
    try:
        whitelisted_source = readstatic.read_static(
            'base64-code-whitelist.txt')
        whitelisted_source = whitelisted_source.splitlines()
    except FileNotFoundError:
        logger.warn("Failed to read whitelisted code for bigbrother")
        whitelisted_source = []

    code_b64 = base64.b64encode(info[0].co_code).decode()
    if code_b64 in whitelisted_source:
        return
    #uncomment when you want to build on the whitelist
    else:
       with open("../static-data/base64-code-whitelist.txt", "a") as f:
           f.write(code_b64 + "\n")
       return

    for source in whitelisted_code:
        if info[0].co_filename.endswith(source):
            return

    if 'plugins/' in info[0].co_filename:
        return

    logger.warn('POSSIBLE EXPLOIT DETECTED, SEE LOGS', terminal=True)
    logger.warn('POSSIBLE EXPLOIT DETECTED: ' + info[0].co_filename)
    logger.warn('Prevented exec/eval. Report this with the sample below')
    logger.warn(f'{event} code in base64 format: {code_b64}')
    raise ArbitraryCodeExec("Arbitrary code (eval/exec) detected.")