Onion from public key

onion_from_pub.py

import hashlib
import base64
from Crypto.PublicKey import RSA
import sys

# U=$(openssl rsa -in a.pem -pubout -outform DER | tail -c +23 | shasum | head -c 20 | python -c "import base64,sys; print base64.b32encode(sys.stdin.readline().strip('\n').decode('hex')).lower()"); echo "http://${U}.onion"
with open(sys.argv[1]) as f:
  pem = f.read()


key = RSA.importKey(pem)
pub = key.publickey()
der = pub.exportKey('DER')

h = hashlib.sha1(der[22:])
onion = base64.b32encode(h.digest())[:16]
print("%s.onion" % onion.decode().lower())