pgpry - PGP private key recovery
Copyright (C) 2010 Jonas Gehring
================================


pgpry is a Pthread-based password recovery program for private OpenPGP
keys.  It reads private key data from stdin and performs a brute-force
attack in order to recover the pass phrase. Numerous options for
restricting the key space are offered, including regular expression
filtering and prefix/suffix filters.


FEATURES
--------

  - Guessing based on a dictionary or a character set (incremental
    and random guessing)
  - State saving and restoring (for incremental guessing)
  - Regular expression filtering
  - Addition of prefixes/suffixes to the guessed words
  - Parsing of binary and ASCII-armored OpenPGP data


DEPENDENCIES
------------

pgpry utilizes the following libraries:

  - OpenSSL (libcrypto, libssl)
  - POSIX threads (libpthread)
  - Standard C++ runtime (libstdc++)

These are compile-time as well as run-time dependencies.


USAGE INFORMATION
-----------------

For general usage information, run pgpry with "--help". More specific
usage instructions follow.

  - Regular expression filtering:
    Regular expressions are read from the file name supplied via the
    respective command line argument. The following format is used
    (indentation added for clarity):

      + $POSITIVE_REGEX
      - $NEGATIVE_REGEX
      ...

    A pass phrase will be tested if it matches all positive expressions
    and doesn't match any negative expression.

  - Prefix/Suffix filtering:
    Regular expression filtering can be time-consuming. If possible
    prefixes or suffixes are known, they can be passed as command-line
    arguments instead.


OPTIONAL FEATURES
-----------------

pgpry ships with optional features. They aren't included in the default
build since they either depend on specific hardware or are licensed
under a different model then pgpry.  All of those features can be enabled
using the configure script shipping with the source distribution. Here's
a detailed listing of the currently offered optional features:

  - block-sha1 (--enable-block-sha1):
    Use the fast SHA1 algorithm from the git distribution, written by
    Linus Torvalds.  This algorithm should be faster than those included
    in the OpenSSL distribution. However, it is licensed under the GPL
    version 2, whereas pgpry is licensed under version 3. Please see
    src/3rdparty/block-sha1/COPYING for further information.


AUTHOR
------
Jonas Gehring <jonas.gehring@boolsoft.org>


LICENSE
-------

pgpry - PGP private key recovery
Copyright (C) 2010 Jonas Gehring

This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program.  If not, see <http://www.gnu.org/licenses/>.