Determine password for a PGP private key based on a wordlist.

gpg_bruteforce.py

#!/usr/bin/env python
"""
Determine password for a PGP private key based on a wordlist.
Also performs permutations on passwords in the case of l33tsp3ak, etc.

Requires python-gnupg (easy_install/pip install python-gnupg)

To quiet down some of the exceptions during signing attempts, the following
"patch" is needed within gnupg.py:

--- gnupg.py  2011-05-24 13:11:23.000000000 -0400
+++ gnupg_patched.py    2011-05-24 16:02:52.000000000 -0400
@@ -974,6 +974,8 @@
         if key in ("USERID_HINT", "NEED_PASSPHRASE", "BAD_PASSPHRASE",
                    "GOOD_PASSPHRASE", "BEGIN_SIGNING"):
             pass
+        elif key == "INV_SGNR":
+            pass
         elif key == "SIG_CREATED":
             (self.type,
              algo, hashalgo, cls,

Example Usage:
    gpg_bruteforce.py <key_id> [-p] < /usr/share/dict/words

Copyleft 2011 Ian Gallagher <crash@neg9.org>
Inspired by idea/work of Aaron Grattifiori <dyn@neg9.org>
"""
import sys
import os
from datetime import datetime
from gnupg import GPG


def verifyPassphrase(signing_key, key_passphrase):
    """
    Return True if passphrase is correct, False if it is not
    """
    # Setup GPG
    gnupg_home = "%s/.gnupg" % os.environ['HOME']
    gpg = GPG(gnupghome=gnupg_home)

    sig = None
    try:
        # This bugger is threaded, so catching exceptions from it isn't really something that works so great
        sig = gpg.sign('Test String', keyid=signing_key, passphrase=key_passphrase, clearsign=False)
    except Exception:
        pass

    if sig:
        return True
    else:
        return False

if "__main__" == __name__:
    if len(sys.argv) < 2:
        print >>sys.stderr, "usage: %s <key_id> [-p] < <wordlist>" % sys.argv[0]
        print >>sys.stderr, "\t<key_id>: PGP KeyID/Fingerprint to test."
        print >>sys.stderr, "\t-p: Attempt variations of each word in the wordlist."
        print >>sys.stderr, "\t<wordlist>: A file containing passwords to attempt, one per line."

        sys.exit(1)

    keyid = sys.argv[1]
    try_permutations = True if (len(sys.argv) > 2 and sys.argv[2].lower() == '-p') else False

    attempts = 0
    valid_password = None

    passwords = sys.stdin.readlines()

    time_start = datetime.now()

    for password in passwords:
        attempts += 1
        if verifyPassphrase(keyid, password):
            valid_password = password
            break

        if try_permutations:
            """
            Need to write some code that will take a word, and make a generator of all/many
            variations of it based on latin "rules" of some sort.
            E.g/: catfish -> c4tfish, ca7fish, catf!sh, c4tf!5h, Catfish, caTfish, ...
            """
            # TODO: Implement below
            """
            for permutation in permutate(password):
                attempts += 1
                if verifyPassphrase(keyid, permutation):
                    valid_password = password
                    break
            """

    time_end = datetime.now()

    if valid_password:
        print "Success! Passphrase for keyid %s: %s" % (keyid, valid_password[:-1] if valid_password[-1] == "\n" else valid_password)
        print >>sys.stderr, "Number of attempts until success: %d" % attempts
    else:
        print "Sorry, no password found after %d attempts :(" % attempts

    print >>sys.stderr, "Total run time: %s" % (time_end - time_start)