apparmor/utils/aa-status
Tyler Hicks b786c64b17 utils: Don't use access() to determine readability of profiles file
LSMs, such as AppArmor, aren't consulted when a program calls access(2).
This can result in access(2) returning 0 but a subsequent open(2)
failing.

The aa-status utility was doing the access() -> open() sequence and we
became aware of a large number of tracebacks due to open() failing for
lack of permissions. This patch catches any IOError exceptions thrown by
open(). It continues to print the same error message as before when
access() failed but also prints that error message when AppArmor blocks
the open of the apparmorfs profiles file.

https://launchpad.net/bugs/1466768

Signed-off-by: Tyler Hicks <tyhicks@canonical.com>
Acked-by: Steve Beattie <steve@nxnw.org>
2015-06-22 10:14:14 -05:00

207 lines
6.6 KiB
Python
Executable file

#! /usr/bin/env python
# ------------------------------------------------------------------
#
# Copyright (C) 2005-2006 Novell/SUSE
# Copyright (C) 2011 Canonical Ltd.
#
# This program is free software; you can redistribute it and/or
# modify it under the terms of version 2 of the GNU General Public
# License published by the Free Software Foundation.
#
# ------------------------------------------------------------------
import re, os, sys, errno
def cmd_enabled():
'''Returns error code if AppArmor is not enabled'''
if get_profiles() == {}:
sys.exit(2)
def cmd_profiled():
'''Prints the number of loaded profiles'''
profiles = get_profiles()
sys.stdout.write("%d\n" % len(profiles))
if profiles == {}:
sys.exit(2)
def cmd_enforced():
'''Prints the number of loaded enforcing profiles'''
profiles = get_profiles()
sys.stdout.write("%d\n" % len(filter_profiles(profiles, 'enforce')))
if profiles == {}:
sys.exit(2)
def cmd_complaining():
'''Prints the number of loaded non-enforcing profiles'''
profiles = get_profiles()
sys.stdout.write("%d\n" % len(filter_profiles(profiles, 'complain')))
if profiles == {}:
sys.exit(2)
def cmd_verbose():
'''Displays multiple data points about loaded profile set'''
global verbose
verbose = True
profiles = get_profiles()
processes = get_processes(profiles)
stdmsg("%d profiles are loaded." % len(profiles))
for status in ('enforce', 'complain'):
filtered_profiles = filter_profiles(profiles, status)
stdmsg("%d profiles are in %s mode." % (len(filtered_profiles), status))
for item in filtered_profiles:
stdmsg(" %s" % item)
stdmsg("%d processes have profiles defined." % len(processes))
for status in ('enforce', 'complain', 'unconfined'):
filtered_processes = filter_processes(processes, status)
if status == 'unconfined':
stdmsg("%d processes are unconfined but have a profile defined." % len(filtered_processes))
else:
stdmsg("%d processes are in %s mode." % (len(filtered_processes), status))
# Sort by name, and then by pid
filtered_processes.sort(key=lambda x: int(x[0]))
filtered_processes.sort(key=lambda x: x[1])
for (pid, process) in filtered_processes:
stdmsg(" %s (%s) " % (process, pid))
if profiles == {}:
sys.exit(2)
def get_profiles():
'''Fetch loaded profiles'''
profiles = {}
if os.path.exists("/sys/module/apparmor"):
stdmsg("apparmor module is loaded.")
else:
errormsg("apparmor module is not loaded.")
sys.exit(1)
apparmorfs = find_apparmorfs()
if not apparmorfs:
errormsg("apparmor filesystem is not mounted.")
sys.exit(3)
apparmor_profiles = os.path.join(apparmorfs, "profiles")
try:
f = open(apparmor_profiles)
except IOError as e:
if e.errno == errno.EACCES:
errormsg("You do not have enough privilege to read the profile set.")
else:
errormsg("Could not open %s: %s" % (apparmor_profiles, os.strerror(e.errno)))
sys.exit(4)
for p in f.readlines():
match = re.search("^([^\(]+)\s+\((\w+)\)$", p)
profiles[match.group(1)] = match.group(2)
f.close()
return profiles
def get_processes(profiles):
'''Fetch process list'''
processes = {}
contents = os.listdir("/proc")
for filename in contents:
if filename.isdigit():
try:
for p in open("/proc/%s/attr/current" % filename).readlines():
match = re.search("^([^\(]+)\s+\((\w+)\)$", p)
if match:
processes[filename] = { 'profile' : match.group(1), \
'mode' : match.group(2) }
elif os.path.realpath("/proc/%s/exe" % filename) in profiles:
# keep only unconfined processes that have a profile defined
processes[filename] = { 'profile' : os.path.realpath("/proc/%s/exe" % filename), \
'mode' : 'unconfined' }
except:
pass
return processes
def filter_profiles(profiles, status):
'''Return a list of profiles that have a particular status'''
filtered = []
for key, value in list(profiles.items()):
if value == status:
filtered.append(key)
filtered.sort()
return filtered
def filter_processes(processes, status):
'''Return a list of processes that have a particular status'''
filtered = []
for key, value in list(processes.items()):
if value['mode'] == status:
filtered.append([key, value['profile']])
return filtered
def find_apparmorfs():
'''Finds AppArmor mount point'''
for p in open("/proc/mounts","rb").readlines():
if p.split()[2].decode() == "securityfs" and \
os.path.exists(os.path.join(p.split()[1].decode(), "apparmor")):
return os.path.join(p.split()[1].decode(), "apparmor")
return False
def errormsg(message):
'''Prints to stderr if verbose mode is on'''
global verbose
if verbose:
sys.stderr.write(message + "\n")
def stdmsg(message):
'''Prints to stdout if verbose mode is on'''
global verbose
if verbose:
sys.stdout.write(message + "\n")
def print_usage():
'''Print usage information'''
sys.stdout.write('''Usage: %s [OPTIONS]
Displays various information about the currently loaded AppArmor policy.
OPTIONS (one only):
--enabled returns error code if AppArmor not enabled
--profiled prints the number of loaded policies
--enforced prints the number of loaded enforcing policies
--complaining prints the number of loaded non-enforcing policies
--verbose (default) displays multiple data points about loaded policy set
--help this message
''' % sys.argv[0])
# Main
global verbose
verbose = False
if len(sys.argv) > 2:
sys.stderr.write("Error: Too many options.\n")
print_usage()
sys.exit(1)
elif len(sys.argv) == 2:
cmd = sys.argv.pop(1)
else:
cmd = '--verbose'
# Command dispatch:
commands = {
'--enabled' : cmd_enabled,
'--profiled' : cmd_profiled,
'--enforced' : cmd_enforced,
'--complaining' : cmd_complaining,
'--verbose' : cmd_verbose,
'-v' : cmd_verbose,
'--help' : print_usage,
'-h' : print_usage
}
if cmd in commands:
commands[cmd]()
sys.exit(0)
else:
sys.stderr.write("Error: Invalid command.\n")
print_usage()
sys.exit(1)