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#!/usr/bin/python
# -*- coding: utf-8 -*-
import time
import base64
import argparse
# from pympler.asizeof import asizeof
from certtools import *
base_urls = ["https://plausible.ct.nordu.net/",
"https://ct1.digicert-ct.com/log/",
"https://ct.izenpe.com/",
"https://log.certly.io/",
"https://ct.googleapis.com/aviator/",
"https://ct.googleapis.com/pilot/",
"https://ct.googleapis.com/rocketeer/",
]
logkeys = {}
logkeys["https://plausible.ct.nordu.net/"] = get_public_key_from_file("../../plausible-logkey.pem")
logkeys["https://ct.googleapis.com/rocketeer/"] = get_public_key_from_file("../../rocketeer-logkey.pem")
logkeys["https://ct.googleapis.com/aviator/"] = get_public_key_from_file("../../aviator-logkey.pem")
logkeys["https://ct.googleapis.com/pilot/"] = get_public_key_from_file("../../pilot-logkey.pem")
logkeys["https://log.certly.io/"] = get_public_key_from_file("../../certly-logkey.pem")
logkeys["https://ct.izenpe.com/"] = get_public_key_from_file("../../izenpe-logkey.pem")
logkeys["https://ct1.digicert-ct.com/log/"] = get_public_key_from_file("../../digicert-logkey.pem")
parser = argparse.ArgumentParser(description="")
parser.add_argument('--audit', action='store_true', help="run lightweight auditor verifying consistency in STH")
parser.add_argument('--audit2', action='store_true', help="run medium-weight auditor verifying consistency in STH and inclusion proofs of new entries")
parser.add_argument('--build-sth', action='store_true', help="get all entries and construct STH")
parser.add_argument('--verify-index', default=None, help="Verify a specific index in all logs" )
parser.add_argument('--verify-hash', action='store_true', help="Verify a specific index in all logs" )
def reduce_layer(layer):
new_layer = []
while len(layer) > 1:
e1 = layer.pop(0)
e2 = layer.pop(0)
new_layer.append(internal_hash((e1,e2)))
return new_layer
def reduce_tree(entries, layers):
if len(entries) == 0 and layers is []:
return [[hashlib.sha256().digest()]]
layer_idx = 0
layers[layer_idx] += entries
while len(layers[layer_idx]) > 1:
if len(layers) == layer_idx + 1:
layers.append([])
layers[layer_idx + 1] += reduce_layer(layers[layer_idx])
layer_idx += 1
return layers
def reduce_subtree_to_root(layers):
while len(layers) > 1:
if len(layers[1]) == 0:
layers[1] = layers[0]
else:
layers[1] += next_merkle_layer(layers[0])
del layers[0]
if len(layers[0]) > 1:
return next_merkle_layer(layers[0])
return layers[0]
def fetch_all_sth():
sths = {}
for base_url in base_urls:
try:
sths[base_url] = get_sth(base_url)
except:
print "Failed to retrieve STH from " + base_url
continue
try:
check_sth_signature(base_url, sths[base_url], logkeys[base_url])
except:
print "Could not verify signature from " + base_url + "!!!"
continue
return sths
def verify_consistency(old, new):
for url in old:
# try:
if old[url]["tree_size"]!= new[url]["tree_size"]:
consistency_proof = get_consistency_proof(url, old[url]["tree_size"], new[url]["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[url]["tree_size"], new[url]["tree_size"], old[url]["sha256_root_hash"])
if old[url]["sha256_root_hash"] != str(base64.b64encode(res[0])):
print "Verification of old hash failed!!!"
print old[url]["sha256_root_hash"], str(base64.b64encode(res[0]))
elif new[url]["sha256_root_hash"] != str(base64.b64encode(res[1])):
print "Verification of new hash failed!!!"
print new[url]["sha256_root_hash"], str(base64.b64encode(res[1]))
else:
print time.strftime("%H:%M:%S", time.gmtime()) + " New STH from " + url + ", timestamp: " + str(new[url]["timestamp"]) + ", size: " + str(new[url]["tree_size"]) + "...OK."
# except:
# print "ERROR: Could not verify consistency for " + url
def verify_inclusion_all(old, new):
for url in old:
try:
if old[url]["tree_size"]!= new[url]["tree_size"]:
entries = get_entries(url, old[url]["tree_size"]-1, new[url]["tree_size"] -1)["entries"]
success = True
for i in entries:
h = get_leaf_hash(base64.b64decode(i["leaf_input"]))
if not verify_inclusion_by_hash(url, h):
success = False
if success:
print "Verifying inclusion for " + str(len(entries)) + " new entries in " + url + " ...OK"
else:
print "ERROR: Failed to prove inclusion of all new entries in " + url
except:
print "ERROR: Failed to prove inclusion of all new entries in " + url
def fetch_and_build_tree(old_sth, base_url):
sth = old_sth[base_url]
subtree = [[]]
idx = 0
print "Getting all entries from " + base_url
while idx < sth["tree_size"]:
pre_size = idx
entries = get_entries(base_url, idx, sth["tree_size"]-1)["entries"]
new_leafs = []
for item in entries:
new_leafs.append(get_leaf_hash(base64.b64decode(item["leaf_input"])))
idx += len(new_leafs)
print "Got entries " + str(pre_size) + " to " + str(idx) #+ " (tree size: " + str(asizeof(subtree)) + " B)"
subtree = reduce_tree(new_leafs, subtree)
root = base64.b64encode(reduce_subtree_to_root(subtree)[0])
if root == sth["sha256_root_hash"]:
print "Verifying root hashes...OK."
else:
print "ERROR: Failed to verify root hashes!"
print "STH root: " + sth["sha256_root_hash"]
print "Tree root: " + root
def verify_inclusion_by_hash(base_url, leaf_hash):
try:
tmp_sth = get_sth(base_url)
proof = get_proof_by_hash(base_url, leaf_hash, tmp_sth["tree_size"])
decoded_inclusion_proof = []
for item in proof["audit_path"]:
decoded_inclusion_proof.append(base64.b64decode(item))
root = base64.b64encode(verify_inclusion_proof(decoded_inclusion_proof, proof["leaf_index"], tmp_sth["tree_size"], leaf_hash))
if tmp_sth["sha256_root_hash"] == root:
# print "Verifying inclusion for entry " + str(proof["leaf_index"]) + " in " + base_url + "...OK."
return True
else:
print "ERROR: Could not prove inclusion for entry " + str(proof["leaf_index"]) + " in " + base_url
return False
except:
print "ERROR: Could not prove inclusion for hashed entry in " + base_url
return False
def verify_inclusion_by_index(base_url, index):
try:
tmp_sth = get_sth(base_url)
proof = get_proof_by_index(base_url, index, tmp_sth["tree_size"])
decoded_inclusion_proof = []
for item in proof["audit_path"]:
decoded_inclusion_proof.append(base64.b64decode(item))
root = base64.b64encode(verify_inclusion_proof(decoded_inclusion_proof, index, tmp_sth["tree_size"], get_leaf_hash(base64.b64decode(proof["leaf_input"]))))
if tmp_sth["sha256_root_hash"] == root:
print "Verifying inclusion for entry " + str(index) + " in " + base_url + "...OK."
else:
print "ERROR: Could not prove inclusion for entry " + str(index) + " in " + base_url
except:
print "ERROR: Could not prove inclusion for entry " + str(index) + " in " + base_url
def get_proof_by_index(baseurl, index, tree_size):
try:
params = urllib.urlencode({"leaf_index":index,
"tree_size":tree_size})
result = \
urlopen(baseurl + "ct/v1/get-entry-and-proof?" + params).read()
return json.loads(result)
except urllib2.HTTPError, e:
print "ERROR:", e.read()
sys.exit(0)
def main(args):
print "Started " + time.strftime("%H:%M:%S", time.gmtime())
if args.verify_index is None and not args.build_sth and not args.audit and not args.audit2 and not args.verify_hash:
print "Nothing to do."
return
else:
sth = fetch_all_sth()
if args.verify_index is not None:
for url in base_urls:
verify_inclusion_by_index(url, int(args.verify_index))
if args.verify_hash:
idx = 1337
url = base_urls[0]
entries = get_entries(url, idx, idx)["entries"]
h = get_leaf_hash(base64.b64decode(entries[0]["leaf_input"]))
verify_inclusion_by_hash(url, h)
if args.build_sth:
print "Building trees from entries. This may take a while, go get coffee or something..."
fetch_and_build_tree(sth, base_urls[2])
if args.audit:
print "Running auditor for " +str(len(base_urls)) + " logs..."
while True:
time.sleep(1*60-4)
new_sth = fetch_all_sth()
verify_consistency(sth, new_sth)
sth = new_sth
if args.audit2:
print "Running auditor2 for " +str(len(base_urls)) + " logs..."
while True:
time.sleep(1*60-4)
new_sth = fetch_all_sth()
verify_consistency(sth, new_sth)
verify_inclusion_all(sth, new_sth)
sth = new_sth
print "Done. Exiting..."
if __name__ == '__main__':
main(parser.parse_args())
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