vmware-nsx/quantum/rootwrap/filters.py
Maru Newby 6c97b81bf3 Update codebase for HACKING compliance.
* This is a massive patch that aims to clean up the codebase
   and bring it into compliance with HACKING.rst and PEP8 in one
   fell swoop.
 * Cleaned up use of gettext.
 * Updated log usage for consistency.
 * The tests run successfully against all plugins except
   cisco and nicira (due to dependency issues with these plugins).
 * Addresses bug 981208

Change-Id: I4d8c7ab138d8f7bb906d18dc34f88f8bd0581c19
2012-05-01 11:46:24 -07:00

141 lines
4.6 KiB
Python

# vim: tabstop=4 shiftwidth=4 softtabstop=4
# Copyright (c) 2012 Openstack, LLC.
# All Rights Reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License"); you may
# not use this file except in compliance with the License. You may obtain
# a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
# License for the specific language governing permissions and limitations
# under the License.
import os
import re
class CommandFilter(object):
"""Command filter only checking that the 1st argument matches exec_path"""
def __init__(self, exec_path, run_as, *args):
self.exec_path = exec_path
self.run_as = run_as
self.args = args
def match(self, userargs):
"""Only check that the first argument (command) matches exec_path"""
return os.path.basename(self.exec_path) == userargs[0]
def get_command(self, userargs):
"""Returns command to execute (with sudo -u if run_as != root)."""
if (self.run_as != 'root'):
# Used to run commands at lesser privileges
return ['sudo', '-u', self.run_as, self.exec_path] + userargs[1:]
return [self.exec_path] + userargs[1:]
def get_environment(self, userargs):
"""Returns specific environment to set, None if none"""
return None
class RegExpFilter(CommandFilter):
"""Command filter doing regexp matching for every argument"""
def match(self, userargs):
# Early skip if command or number of args don't match
if (len(self.args) != len(userargs)):
# DENY: argument numbers don't match
return False
# Compare each arg (anchoring pattern explicitly at end of string)
for (pattern, arg) in zip(self.args, userargs):
try:
if not re.match(pattern + '$', arg):
break
except re.error:
# DENY: Badly-formed filter
return False
else:
# ALLOW: All arguments matched
return True
# DENY: Some arguments did not match
return False
class DnsmasqFilter(CommandFilter):
"""Specific filter for the dnsmasq call (which includes env)"""
def match(self, userargs):
if (userargs[0].startswith("FLAGFILE=") and
userargs[1].startswith("NETWORK_ID=") and
userargs[2] == "dnsmasq"):
return True
return False
def get_command(self, userargs):
return [self.exec_path] + userargs[3:]
def get_environment(self, userargs):
env = os.environ.copy()
env['FLAGFILE'] = userargs[0].split('=')[-1]
env['NETWORK_ID'] = userargs[1].split('=')[-1]
return env
class KillFilter(CommandFilter):
"""Specific filter for the kill calls.
1st argument is a list of accepted signals (emptystring means no signal)
2nd argument is a list of accepted affected executables.
This filter relies on /proc to accurately determine affected
executable, so it will only work on procfs-capable systems (not OSX).
"""
def match(self, userargs):
if userargs[0] != "kill":
return False
args = list(userargs)
if len(args) == 3:
signal = args.pop(1)
if signal not in self.args[0]:
# Requested signal not in accepted list
return False
elif len(args) != 2:
# Incorrect number of arguments
return False
elif '' not in self.args[0]:
# No signal, but list doesn't include empty string
return False
try:
command = os.readlink("/proc/%d/exe" % int(args[1]))
if command not in self.args[1]:
# Affected executable not in accepted list
return False
except (ValueError, OSError):
# Incorrect PID
return False
return True
class ReadFileFilter(CommandFilter):
"""Specific filter for the utils.read_file_as_root call"""
def __init__(self, file_path, *args):
self.file_path = file_path
super(ReadFileFilter, self).__init__("/bin/cat", "root", *args)
def match(self, userargs):
if userargs[0] != 'cat':
return False
if userargs[1] != self.file_path:
return False
if len(userargs) != 2:
return False
return True