mirror of
https://github.com/romanz/amodem.git
synced 2026-02-24 16:18:12 +08:00
51 lines
1.5 KiB
Python
Executable File
51 lines
1.5 KiB
Python
Executable File
#!/usr/bin/env python
|
|
"""Check GPG v2 signature for a given public key."""
|
|
import argparse
|
|
import base64
|
|
import io
|
|
import logging
|
|
|
|
from . import decode
|
|
from .. import util
|
|
|
|
log = logging.getLogger(__name__)
|
|
|
|
|
|
def original_data(filename):
|
|
"""Locate and load original file data, whose signature is provided."""
|
|
parts = filename.rsplit('.', 1)
|
|
if len(parts) == 2 and parts[1] in ('sig', 'asc'):
|
|
log.debug('loading file %s', parts[0])
|
|
return open(parts[0], 'rb').read()
|
|
|
|
|
|
def verify(pubkey, sig_file):
|
|
"""Verify correctness of public key and signature."""
|
|
stream = open(sig_file, 'rb')
|
|
if stream.name.endswith('.asc'):
|
|
lines = stream.readlines()[3:-1]
|
|
data = base64.b64decode(''.join(lines))
|
|
payload, checksum = data[:-3], data[-3:]
|
|
assert util.crc24(payload) == checksum
|
|
stream = io.BytesIO(payload)
|
|
parser = decode.Parser(util.Reader(stream), original_data(sig_file))
|
|
signature, = list(parser)
|
|
decode.verify_digest(pubkey=pubkey, digest=signature['digest'],
|
|
signature=signature['sig'], label='GPG signature')
|
|
log.info('%s OK', sig_file)
|
|
|
|
|
|
def main():
|
|
"""Main function."""
|
|
logging.basicConfig(level=logging.DEBUG,
|
|
format='%(asctime)s %(levelname)-10s %(message)s')
|
|
p = argparse.ArgumentParser()
|
|
p.add_argument('pubkey')
|
|
p.add_argument('signature')
|
|
args = p.parse_args()
|
|
verify(pubkey=decode.load_public_key(open(args.pubkey, 'rb')),
|
|
sig_file=args.signature)
|
|
|
|
if __name__ == '__main__':
|
|
main()
|