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#!/usr/bin/python
# -*- coding: utf-8 -*-
import time
import datetime
import base64
import argparse
import errno
import subprocess
import json
from gaol_lib import *
from lib import *
import os.path
parser = argparse.ArgumentParser(description="")
parser.add_argument('--config', default="gaol_conf.py")
args = parser.parse_args()
# Import from config file
if os.path.isfile(args.config):
modules = map(__import__, [args.config[:-2]])
CONFIG = modules[0]
ERROR_STR = CONFIG.ERROR_STR
else:
print "Config file not found!"
ERROR_STR = "(local)ERROR: "
sys.exit()
def email(s):
for addr in CONFIG.EMAIL_ADDR:
p = subprocess.Popen(
["mail", "-s", CONFIG.EMAIL_SUBJECT, addr],
stdin=subprocess.PIPE, stdout=subprocess.PIPE,
stderr=subprocess.PIPE)
p.communicate(s)
class ctlog:
def __init__(self, name, url, key, log_id=None, build=True):
self.name = name
self.url = url
self.key = key
self.log_id = log_id
self.logfile = CONFIG.OUTPUT_DIR + name + ".log"
self.savefile = CONFIG.OUTPUT_DIR + name + "-state-info.json"
self.subtree = [[]]
# self.fe_ips = {}
self.sth = None
self.entries = 0
self.root_hash = None
self.build = build
self.saved_sth = None
self.saved_entries = None
self.saved_subtree = None
self.log("Starting monitor")
def to_dict(self):
d = {}
d["sth"] = self.sth
return d
def save(self):
self.log("Saving state to file")
open(self.savefile, 'w').write(json.dumps(self.to_dict()))
def load(self):
self.log("Loading state from file")
try:
f = open(self.savefile)
s = f.read()
d = json.loads(s)
self.sth = d["sth"]
except IOError, e:
if e.errno == errno.ENOENT:
return None
raise e
def log(self, string):
s = time_str() + " " + string
with open(self.logfile, 'a') as f:
f.write(s + "\n")
f.close()
email(s)
def update_sth(self):
try:
new_sth = get_sth(self.url)
except Exception, e:
self.log(ERROR_STR + "Failed to fetch STH. " +str(e))
return
try:
check_sth_signature(self.url, new_sth, base64.b64decode(self.key))
except:
self.log(ERROR_STR + "Could not verify STH signature " + str(new_sth))
if self.sth:
sth_time = time_str(new_sth["timestamp"])
if new_sth["timestamp"] != self.sth["timestamp"]:
self.log("STH updated. Size: " + str(new_sth["tree_size"]) + ", Time: " + sth_time)
self.sth = new_sth
else:
self.log("Setting initial STH: " + str(new_sth))
self.sth = new_sth
def verify_progress(self, old):
new = self.sth
try:
if new["tree_size"] == old["tree_size"]:
if old["sha256_root_hash"] != new["sha256_root_hash"]:
self.log(ERROR_STR + "New root hash for same tree size! Old:" + str(old) + " New:" + str(new))
elif new["tree_size"] < old["tree_size"]:
self.log(ERROR_STR + "New tree is smaller than old tree! Old:" + str(old) + " New:" + str(new))
if new["timestamp"] < old["timestamp"]:
self.log(ERROR_STR + "Regression in timestamps! Old:" + str(old) + " New:" + str(new))
else:
age = time.time() - new["timestamp"]/1000
sth_time = time_str(new["timestamp"])
roothash = new['sha256_root_hash']
if age > 24 * 3600:
s = ERROR_STR + "STH is older than 24h: %s UTC" % (sth_time)
self.log(s + str(new))
print s
elif age > 12 * 3600:
s = "WARNING: STH is older than 12h: %s UTC" % (sth_time)
self.log(s)
elif age > 6 * 3600:
s = "WARNING: STH is older than 6h: %s UTC" % (sth_time)
self.log(s)
except Exception, e:
self.log(ERROR_STR + "Failed to verify progress! Old:" + str(old) + " New:" + str(new) + " Exception: " + str(e))
def verify_consistency(self, old):
new = self.sth
try:
if old["tree_size"]!= new["tree_size"]:
consistency_proof = get_consistency_proof(self.url, old["tree_size"], new["tree_size"])
decoded_consistency_proof = []
for item in consistency_proof:
decoded_consistency_proof.append(base64.b64decode(item))
res = verify_consistency_proof(decoded_consistency_proof, old["tree_size"], new["tree_size"], base64.b64decode(old["sha256_root_hash"]))
if old["sha256_root_hash"] != str(base64.b64encode(res[0])):
self.log(ERROR_STR + "Verification of consistency for old hash failed! Old:" \
+ str(old) + " New:" + str(new) + " Calculated:" + str(base64.b64encode(res[0]))\
+ " Proof:" + str(consistency_proof))
elif new["sha256_root_hash"] != str(base64.b64encode(res[1])):
self.log(ERROR_STR + "Verification of consistency for new hash failed! Old:" \
+ str(old) + " New:" + str(new) + " Proof:" + str(consistency_proof))
except Exception, e:
self.log(ERROR_STR + "Could not verify consistency! " + " Old:" + str(old) + " New:" + str(new) + " Error:" + str(e))
def main(args):
# Create logs
logs = []
try:
# Create log objects
for item in CONFIG.CTLOGS:
logs.append(ctlog(item["name"], item["url"], item["key"], item["id"], item["build"]))
print time_str() + " Setting up monitor for " + str(len(logs)) + " logs..."
# Set up state
for log in logs:
if os.path.isfile(log.savefile):
log.load()
# Main loop: Auditor
print time_str() + " Running... (see logfiles for output)"
while True:
for log in logs:
old_sth = log.sth
log.update_sth()
if old_sth and old_sth["timestamp"] != log.sth["timestamp"]:
log.verify_progress(old_sth)
log.verify_consistency(old_sth) # Does rollback on critical fail
pass
time.sleep(CONFIG.INTERVAL)
# Normal exit of the program
except KeyboardInterrupt:
print time_str() + ' Received interrupt from user. Saving and exiting....'
for log in logs:
log.save()
# Something went horribly wrong!
except Exception, err:
print Exception, err
for log in logs:
log.save()
if __name__ == '__main__':
if CONFIG.OUTPUT_DIR and not os.path.exists(CONFIG.OUTPUT_DIR):
os.makedirs(CONFIG.OUTPUT_DIR)
main(args)
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