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#!/usr/bin/env python
#
# Licensed to the Apache Software Foundation (ASF) under one or more
# contributor license agreements. See the NOTICE file distributed with
# this work for additional information regarding copyright ownership.
# The ASF licenses this file to You under the Apache License, Version 2.0
# (the "License"); you may not use this file except in compliance with
# the License. You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
import binascii
import os
import sqlite3
import ssl
import struct
import sys
import tempfile
from contextlib import closing
SERVER_START = 1
KEY_START = 2
CERT_START = 3
SCT_START = 4
def usage():
print >> sys.stderr, ('Usage: %s /path/to/audit/files ' +
'[/path/to/log-config-db]') % sys.argv[0]
sys.exit(1)
def audit(fn, tmp, already_checked, cur):
print 'Auditing %s...' % fn
# First, parse the audit file into a series of related
#
# 1. PEM file with certificate chain
# 2. Individual SCT files
#
# Next, for each SCT, invoke verify_single_proof to verify.
log_bytes = open(fn, 'rb').read()
offset = 0
while offset < len(log_bytes):
print 'Got package from server...'
val = struct.unpack_from('>H', log_bytes, offset)
assert val[0] == SERVER_START
offset += 2
assert struct.unpack_from('>H', log_bytes, offset)[0] == KEY_START
offset += 2
key_size = struct.unpack_from('>H', log_bytes, offset)[0]
assert key_size > 0
offset += 2
key = log_bytes[offset:offset + key_size]
offset += key_size
# at least one certificate
assert struct.unpack_from('>H', log_bytes, offset)[0] == CERT_START
# for each certificate:
leaf = None
while struct.unpack_from('>H', log_bytes, offset)[0] == CERT_START:
offset += 2
val = struct.unpack_from('BBB', log_bytes, offset)
offset += 3
der_size = (val[0] << 16) | (val[1] << 8) | (val[2] << 0)
print ' Certificate size:', hex(der_size)
if not leaf:
leaf = (offset, der_size)
offset += der_size
pem = ssl.DER_cert_to_PEM_cert(log_bytes[leaf[0]:leaf[0] + leaf[1]])
tmp_leaf_pem = tempfile.mkstemp(text=True)
with closing(os.fdopen(tmp_leaf_pem[0], 'w')) as f:
f.write(pem)
# at least one SCT
assert struct.unpack_from('>H', log_bytes, offset)[0] == SCT_START
# for each SCT:
while offset < len(log_bytes) and \
struct.unpack_from('>H', log_bytes, offset)[0] == SCT_START:
offset += 2
len_offset = offset
sct_size = struct.unpack_from('>H', log_bytes, len_offset)[0]
offset += 2
print ' SCT size:', hex(sct_size)
log_id = log_bytes[offset + 1:offset + 1 + 32]
log_id_hex = binascii.hexlify(log_id).upper()
print ' Log id: %s' % log_id_hex
timestamp_ms = struct.unpack_from('>Q', log_bytes, offset + 33)[0]
print ' Timestamp: %s' % timestamp_ms
# If we ever need the full SCT: sct = (offset, sct_size)
offset += sct_size
if key in already_checked:
print ' (SCTs already checked)'
continue
already_checked[key] = True
log_url_arg = ''
if cur:
stmt = 'SELECT * FROM loginfo WHERE log_id = ?'
cur.execute(stmt, [log_id_hex])
recs = list(cur.fetchall())
if len(recs) > 0 and recs[0][6] is not None:
log_url = recs[0][6]
# verify_single_proof doesn't accept <scheme>://
if '://' in log_url:
log_url = log_url.split('://')[1]
log_url_arg = '--log_url %s' % log_url
print ' Log URL: ' + log_url
cmd = 'verify_single_proof.py --cert %s --timestamp %s %s' % \
(tmp_leaf_pem[1], timestamp_ms, log_url_arg)
print '>%s<' % cmd
os.system(cmd)
os.unlink(tmp_leaf_pem[1])
def main():
if len(sys.argv) != 2 and len(sys.argv) != 3:
usage()
top = sys.argv[1]
tmp = '/tmp'
if len(sys.argv) == 3:
cxn = sqlite3.connect(sys.argv[2])
cur = cxn.cursor()
else:
cur = None
# could serialize this between runs to further limit duplicate checking
already_checked = dict()
for dirpath, dnames, fnames in os.walk(top):
fnames = [fn for fn in fnames if fn[-4:] == '.out']
for fn in fnames:
audit(os.path.join(dirpath, fn), tmp, already_checked, cur)
if __name__ == "__main__":
main()
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