netbeacon/nb_verify.py

53 lines
1.3 KiB
Python

import socket
import datetime
import time
import sys
try:
from hashlib import sha1
except ImportError:
from sha import sha as sha1
import hmac
## nb;epochvalue;sq;hmac
## hmacfunc("nb;epochvalue;sq;", psk)
def nbsign(message=None, psk="netbeacon"):
auth = hmac.new(psk, message, sha1)
return auth.hexdigest()
message_keys = ['header','epoch','sequence','hmac']
def nbparse(message=None):
if message is None:
return False
i = 0
m = {}
for v in line.rsplit(';'):
if message_keys[i] == "epoch" or message_keys[i] == "sequence":
m[message_keys[i]] = int(v)
else:
m[message_keys[i]] = v
i = i +1
return m
def deltafromnow(epoch=None):
if epoch is None:
return False
t = datetime.datetime.now()
now = time.mktime(t.timetuple())
return now-epoch
for line in sys.stdin:
line = line.rstrip()
m = {}
m = nbparse(message=line)
print m['hmac']
message = m['header']+";"+str(m['epoch'])+";"+str(m['sequence'])+";"
if m['hmac'] == nbsign(message=message):
print "valid signature for "+message
timedelta = deltafromnow(epoch=m['epoch'])
print "Time delay "+str(timedelta)
else:
print "(!) invalid signature for "+message
#signature = line.rsplit(';')[-1:]