[scanner] add host class, name mapper and pre-config logic

This commit is contained in:
fnux 2021-04-25 12:45:34 +02:00
parent bb24d632d6
commit 13e2ad175f
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GPG key ID: 4502C902C00A1E12
3 changed files with 124 additions and 41 deletions

View file

@ -485,7 +485,7 @@ def get_parsers():
parser['scan'].add_argument(
'-m', '--mode', help='Which modes should run',
action='append', default=[],
choices=['scan', 'trigger'])
choices=['scan', 'trigger', 'config'])
parser['scan'].add_argument(
'--list',
action='store_true',
@ -498,6 +498,10 @@ def get_parsers():
'-I', '--interfaces',
action='append', default=[], required=True,
help='On which interfaces to scan/trigger')
parser['scan'].add_argument(
'--name-mapper',
action='store', default=None,
help='Map addresses to names, required for config mode')
parser['scan'].add_argument(
'-d', '--delay',
action='store', default=3600, type=int,

View file

@ -37,7 +37,10 @@ def run(scan, args):
log.debug("Trigger started")
if 'scan' in args.mode:
s = scan.Scanner(interfaces=args.interfaces, args=args)
s = scan.Scanner(
autoconfigure='config' in args.mode,
interfaces=args.interfaces,
name_mapper=args.name_mapper)
s.start()
processes.append(s)
log.debug("Scanner started")
@ -46,24 +49,27 @@ def run(scan, args):
process.join()
def list(scan, args):
s = scan.Scanner(interfaces=args.interfaces, args=args)
s = scan.Scanner(interfaces=args.interfaces, name_mapper=args.name_mapper)
hosts = s.list()
# A full IPv6 addresses id composed of 8 blocks of 4 hexa chars +
# 6 colons.
ipv6_max_size = 8 * 4 + 10
# We format dates as follow: YYYY-MM-DD HH:MM:SS
date_max_size = 8 + 2 + 6 + 2
date_max_size = len(datetime.now().strftime(scan.datetime_format))
name_max_size = 25
print("{} | {}".format(
'link-local address'.ljust(ipv6_max_size),
'last seen'.ljust(date_max_size)))
print('=' * (ipv6_max_size + 3 + date_max_size))
for addr in hosts:
last_seen = datetime.strftime(
datetime.strptime(hosts[addr]['last_seen'].strip(), '%Y-%m-%d %H:%M:%S.%f'),
'%Y-%m-%d %H:%M:%S')
print("{} | {}".format(addr.ljust(ipv6_max_size),last_seen.ljust(date_max_size)))
print("{} | {} | {} | {}".format(
'name'.ljust(name_max_size),
'address'.ljust(ipv6_max_size),
'last seen'.ljust(date_max_size),
'last configured'.ljust(date_max_size)))
print('=' * (name_max_size + 3 + ipv6_max_size + 2 * (3 + date_max_size)))
for host in hosts:
print("{} | {} | {} | {}".format(
host.name(default='-').ljust(name_max_size),
host.address().ljust(ipv6_max_size),
host.last_seen().ljust(date_max_size),
host.last_configured().ljust(date_max_size)))
# CLI processing is defined outside of the main scan class to handle
# non-available optional scapy dependency (instead of crashing mid-flight).
@ -82,6 +88,11 @@ def commandline(args):
# By default scan and trigger, but do not call any action.
args.mode = ['scan', 'trigger', ]
if 'config' in args.mode and args.name_mapper == None:
print('--name-mapper must be specified for scanner config mode.',
file=sys.stderr)
sys.exit(1)
# Print known hosts and exit is --list is specified - do not start
# the scanner.
if args.list:

View file

@ -63,6 +63,69 @@ import cdist.config
logging.basicConfig(level=logging.DEBUG)
log = logging.getLogger("scan")
datetime_format = '%Y-%m-%d %H:%M:%S'
class Host(object):
def __init__(self, addr, outdir, name_mapper=None):
self.addr = addr
self.workdir = os.path.join(outdir, addr)
self.name_mapper = name_mapper
os.makedirs(self.workdir, exist_ok=True)
def __get(self, key, default=None):
fname = os.path.join(self.workdir, key)
value=default
if os.path.isfile(fname):
with open(fname, "r") as fd:
value = fd.readline()
return value
def __set(self, key, value):
fname = os.path.join(self.workdir, key)
with open(fname, "w") as fd:
fd.write(f"{value}")
def name(self, default=None):
if self.name_mapper == None:
return default
fpath = os.path.join(os.getcwd(), self.name_mapper)
if os.path.isfile(fpath) and os.access(fpath, os.X_OK):
out = subprocess.run([fpath, self.addr], capture_output=True)
if out.returncode != 0:
return default
else:
value = out.stdout.decode()
return (None if len(value) == 0 else value)
else:
return default
def address(self):
return self.addr
def last_seen(self, default=None):
raw = self.__get('last_seen')
if raw:
return datetime.datetime.strptime(raw, datetime_format)
else:
return default
def last_configured(self, default=None):
raw = self.__get('last_configured')
if raw:
return datetime.datetime.strptime(raw, datetime_format)
else:
return default
def seen(self):
now = datetime.datetime.now().strftime(datetime_format)
self.__set('last_seen', now)
def configure(self):
# TODO: configure.
now = datetime.datetime.now().strftime(datetime_format)
self.__set('last_configured', now)
class Trigger(object):
"""
@ -108,48 +171,43 @@ class Scanner(object):
Scan for replies of hosts, maintain the up-to-date database
"""
def __init__(self, interfaces, args=None, outdir=None):
def __init__(self, interfaces, autoconfigure=False, outdir=None, name_mapper=None):
self.interfaces = interfaces
self.autoconfigure=autoconfigure
self.name_mapper = name_mapper
self.config_delay = datetime.timedelta(seconds=3600)
if outdir:
self.outdir = outdir
else:
self.outdir = os.path.join(os.environ['HOME'], '.cdist', 'scan')
os.makedirs(self.outdir, exist_ok=True)
self.running_configs = {}
def handle_pkg(self, pkg):
if ICMPv6EchoReply in pkg:
host = pkg['IPv6'].src
log.verbose("Host %s is alive", host)
host = Host(pkg['IPv6'].src, self.outdir, self.name_mapper)
if host.name():
log.verbose("Host %s (%s) is alive", host.name(), host.address())
else:
log.verbose("Host %s is alive", host.address())
host.seen()
dir = os.path.join(self.outdir, host)
fname = os.path.join(dir, "last_seen")
now = datetime.datetime.now()
os.makedirs(dir, exist_ok=True)
# FIXME: maybe adjust the format so we can easily parse again
with open(fname, "w") as fd:
fd.write(f"{now}\n")
# TODO check last config.
if self.autoconfigure and \
host.last_configured(default=datetime.datetime.min) + self.config_delay < datetime.datetime.now():
self.config(host)
def list(self):
hosts = dict()
for linklocal_addr in os.listdir(self.outdir):
workdir = os.path.join(self.outdir, linklocal_addr)
# We ignore any (unexpected) file in this directory.
if os.path.isdir(workdir):
last_seen='-'
last_seen_file = os.path.join(workdir, 'last_seen')
if os.path.isfile(last_seen_file):
with open(last_seen_file, "r") as fd:
last_seen = fd.readline()
hosts[linklocal_addr] = {'last_seen': last_seen}
hosts = []
for addr in os.listdir(self.outdir):
hosts.append(Host(addr, self.outdir, self.name_mapper))
return hosts
def config(self):
def config(self, host):
"""
Configure a host
@ -158,9 +216,19 @@ class Scanner(object):
- Maybe keep dict storing per host processes
- Save the result
- Save the output -> probably aligned to config mode
"""
if host.name() == None:
log.debug("config - could not resolve name for %s, aborting.", host.address())
return
if self.running_configs.get(host.name()) != None:
log.debug("config - is already running for %s, aborting.", host.name())
log.info("config - running against host %s.", host.name())
p = host.configure()
self.running_configs[host.name()] = p
def start(self):
self.process = Process(target=self.scan)
self.process.start()