python: Support quick key creation.

* NEWS: Update.
* lang/python/gpg/constants/__init__.py: Import new file.
* lang/python/gpg/constants/create.py: New file.
* lang/python/gpg/core.py (Context.create_key): New function.
* lang/python/tests/Makefile.am (XTESTS): Add new test.
* lang/python/tests/support.py (TemporaryDirectory): New class.
* lang/python/tests/t-quick-key-creation.py: New file.

Signed-off-by: Justus Winter <justus@g10code.com>

NEWS

@@ -21,6 +21,7 @@ Noteworthy changes in version 1.8.1 (unreleased)
  py: Context.__init__        EXTENDED: New keyword arg home_dir.
  py: Context.home_dir        NEW.
  py: Context.keylist         EXTENDED: New keyword arg mode.
+ py: Context.create_key      NEW.
  py: core.pubkey_algo_string NEW.
  py: core.addrspec_from_uid  NEW.
 

lang/python/gpg/constants/__init__.py

@@ -25,8 +25,8 @@ util.process_constants('GPGME_', globals())
 del util
 
 # For convenience, we import the modules here.
-from . import data, event, keylist, md, pk
+from . import data, keylist, sig # The subdirs.
-from . import protocol, sig, sigsum, status, validity
+from . import create, event, md, pk, protocol, sigsum, status, validity
 
 # A complication arises because 'import' is a reserved keyword.
 # Import it as 'Import' instead.
@@ -34,7 +34,7 @@ globals()['Import'] = getattr(__import__('', globals(), locals(),
                                          [str('import')], 1), "import")
 
 __all__ = ['data', 'event', 'import', 'keylist', 'md', 'pk',
-           'protocol', 'sig', 'sigsum', 'status', 'validity']
+           'protocol', 'sig', 'sigsum', 'status', 'validity', 'create']
 
 # GPGME 1.7 replaced gpgme_op_edit with gpgme_op_interact.  We
 # implement gpg.Context.op_edit using gpgme_op_interact, so the

lang/python/gpg/constants/create.py

@@ -0,0 +1,25 @@
+# Flags for key creation
+#
+# Copyright (C) 2017 g10 Code GmbH
+#
+# This file is part of GPGME.
+#
+# GPGME is free software; you can redistribute it and/or modify it
+# under the terms of the GNU Lesser General Public License as
+# published by the Free Software Foundation; either version 2.1 of the
+# License, or (at your option) any later version.
+#
+# GPGME 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 Lesser General
+# Public License for more details.
+#
+# You should have received a copy of the GNU Lesser General Public
+# License along with this program; if not, see <http://www.gnu.org/licenses/>.
+
+from __future__ import absolute_import, print_function, unicode_literals
+del absolute_import, print_function, unicode_literals
+
+from gpg import util
+util.process_constants('GPGME_CREATE_', globals())
+del util

lang/python/gpg/core.py

@@ -1,4 +1,4 @@
-# Copyright (C) 2016 g10 Code GmbH
+# Copyright (C) 2016-2017 g10 Code GmbH
 # Copyright (C) 2004,2008 Igor Belyi <belyi@users.sourceforge.net>
 # Copyright (C) 2002 John Goerzen <jgoerzen@complete.org>
 #
@@ -501,6 +501,84 @@ class Context(GpgmeWrapper):
         self.set_keylist_mode(mode)
         return self.op_keylist_all(pattern, secret)
 
+    def create_key(self, userid, algorithm=None, expires_in=0, expires=True,
+                   sign=False, encrypt=False, certify=False, authenticate=False,
+                   passphrase=None, force=False):
+        """Create a primary key
+
+        Create a primary key for the user id USERID.
+
+        ALGORITHM may be used to specify the public key encryption
+        algorithm for the new key.  By default, a reasonable default
+        is chosen.  You may use "future-default" to select an
+        algorithm that will be the default in a future implementation
+        of the engine.  ALGORITHM may be a string like "rsa", or
+        "rsa2048" to explicitly request an algorithm and a key size.
+
+        EXPIRES_IN specifies the expiration time of the key in number
+        of seconds since the keys creation.  By default, a reasonable
+        expiration time is chosen.  If you want to create a key that
+        does not expire, use the keyword argument EXPIRES.
+
+        SIGN, ENCRYPT, CERTIFY, and AUTHENTICATE can be used to
+        request the capabilities of the new key.  If you don't request
+        any, a reasonable set of capabilities is selected, and in case
+        of OpenPGP, a subkey with a reasonable set of capabilities is
+        created.
+
+        If PASSPHRASE is None (the default), then the key will not be
+        protected with a passphrase.  If PASSPHRASE is a string, it
+        will be used to protect the key.  If PASSPHRASE is True, the
+        passphrase must be supplied using a passphrase callback or
+        out-of-band with a pinentry.
+
+        Keyword arguments:
+        algorithm    -- public key algorithm, see above (default: reasonable)
+        expires_in   -- expiration time in seconds (default: reasonable)
+        expires      -- whether or not the key should expire (default: True)
+        sign         -- request the signing capability (see above)
+        encrypt      -- request the encryption capability (see above)
+        certify      -- request the certification capability (see above)
+        authenticate -- request the authentication capability (see above)
+        passphrase   -- protect the key with a passphrase (default: no passphrase)
+        force        -- force key creation even if a key with the same userid exists
+                                                          (default: False)
+
+        Returns:
+                     -- an object describing the result of the key creation
+
+        Raises:
+        GPGMEError   -- as signaled by the underlying library
+
+        """
+        if util.is_a_string(passphrase):
+            old_pinentry_mode = self.pinentry_mode
+            old_passphrase_cb = getattr(self, '_passphrase_cb', None)
+            self.pinentry_mode = constants.PINENTRY_MODE_LOOPBACK
+            def passphrase_cb(hint, desc, prev_bad, hook=None):
+                return passphrase
+            self.set_passphrase_cb(passphrase_cb)
+
+        try:
+            self.op_createkey(userid, algorithm,
+                              0, # reserved
+                              expires_in,
+                              None, # extrakey
+                              ((constants.create.SIGN if sign else 0)
+                               | (constants.create.ENCR if encrypt else 0)
+                               | (constants.create.CERT if certify else 0)
+                               | (constants.create.AUTH if authenticate else 0)
+                               | (constants.create.NOPASSWD if passphrase == None else 0)
+                               | (0 if expires else constants.create.NOEXPIRE)
+                               | (constants.create.FORCE if force else 0)))
+        finally:
+            if util.is_a_string(passphrase):
+                self.pinentry_mode = old_pinentry_mode
+                if old_passphrase_cb:
+                    self.set_passphrase_cb(*old_passphrase_cb[1:])
+
+        return self.op_genkey_result()
+
     def assuan_transact(self, command,
                         data_cb=None, inquire_cb=None, status_cb=None):
         """Issue a raw assuan command

lang/python/tests/Makefile.am

@@ -50,7 +50,8 @@ py_tests = t-wrapper.py \
 	t-encrypt-large.py \
 	t-file-name.py \
 	t-idiomatic.py \
-	t-protocol-assuan.py
+	t-protocol-assuan.py \
+	t-quick-key-creation.py
 
 XTESTS = initial.py $(py_tests) final.py
 EXTRA_DIST = support.py $(XTESTS) encrypt-only.asc sign-only.asc \

lang/python/tests/support.py

@@ -20,6 +20,7 @@ del absolute_import, print_function, unicode_literals
 
 import sys
 import os
+import tempfile
 import gpg
 
 # known keys
@@ -72,3 +73,17 @@ def mark_key_trusted(ctx, key):
             return result
     with gpg.Data() as sink:
         ctx.op_edit(key, Editor().edit, sink, sink)
+
+
+# Python2/3 compatibility
+if hasattr(tempfile, "TemporaryDirectory"):
+    # Python3.2 and up
+    TemporaryDirectory = tempfile.TemporaryDirectory
+else:
+    class TemporaryDirectory(object):
+        def __enter__(self):
+            self.path = tempfile.mkdtemp()
+            return self.path
+        def __exit__(self, *args):
+            import shutil
+            shutil.rmtree(self.path)

lang/python/tests/t-quick-key-creation.py

@@ -0,0 +1,151 @@
+#!/usr/bin/env python
+
+# Copyright (C) 2017 g10 Code GmbH
+#
+# This file is part of GPGME.
+#
+# GPGME 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 2 of the License, or
+# (at your option) any later version.
+#
+# GPGME 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 Lesser General
+# Public License for more details.
+#
+# You should have received a copy of the GNU Lesser General Public
+# License along with this program; if not, see <http://www.gnu.org/licenses/>.
+
+from __future__ import absolute_import, print_function, unicode_literals
+del absolute_import, print_function, unicode_literals
+
+import gpg
+import itertools
+import os
+import shutil
+import time
+
+import support
+
+alpha = "Alpha <alpha@invalid.example.net>"
+
+def copy_configuration(destination):
+    home = os.environ['GNUPGHOME']
+    shutil.copy(os.path.join(home, "gpg.conf"), destination)
+    shutil.copy(os.path.join(home, "gpg-agent.conf"), destination)
+
+with support.TemporaryDirectory() as tmp:
+    copy_configuration(tmp)
+    with gpg.Context(home_dir=tmp) as ctx:
+        res = ctx.create_key(alpha)
+
+        keys = list(ctx.keylist())
+        assert len(keys) == 1, "Weird number of keys created"
+
+        key = keys[0]
+        assert key.fpr == res.fpr
+        assert len(key.subkeys) == 2, "Expected one primary key and one subkey"
+        assert key.subkeys[0].expires > 0, "Expected primary key to expire"
+
+        # Try to create a key with the same UID
+        try:
+            ctx.create_key(alpha)
+            assert False, "Expected an error but got none"
+        except gpg.errors.GpgError as e:
+            pass
+
+        # Try to create a key with the same UID, now with force!
+        res2 = ctx.create_key(alpha, force=True)
+        assert res.fpr != res2.fpr
+
+
+# From here on, we use one context, and create unique UIDs
+uid_counter = 0
+def make_uid():
+    global uid_counter
+    uid_counter += 1
+    return "user{0}@invalid.example.org".format(uid_counter)
+
+with support.TemporaryDirectory() as tmp:
+    copy_configuration(tmp)
+    with gpg.Context(home_dir=tmp) as ctx:
+
+        # Check gpg.constants.create.NOEXPIRE...
+        res = ctx.create_key(make_uid(), expires=False)
+        key = ctx.get_key(res.fpr, secret=True)
+        assert key.fpr == res.fpr
+        assert len(key.subkeys) == 2, "Expected one primary key and one subkey"
+        assert key.subkeys[0].expires == 0, "Expected primary key not to expire"
+
+        t = 2 * 24 * 60 * 60
+        slack = 5 * 60
+        res = ctx.create_key(make_uid(), expires_in=t)
+        key = ctx.get_key(res.fpr, secret=True)
+        assert key.fpr == res.fpr
+        assert len(key.subkeys) == 2, "Expected one primary key and one subkey"
+        assert abs(time.time() + t - key.subkeys[0].expires) < slack, \
+            "Primary keys expiration time is off"
+
+        # Check capabilities
+        for sign, encrypt, certify, authenticate in itertools.product([False, True],
+                                                                      [False, True],
+                                                                      [False, True],
+                                                                      [False, True]):
+            # Filter some out
+            if not (sign or encrypt or certify or authenticate):
+                # This triggers the default capabilities tested before.
+                continue
+            if (sign or encrypt or authenticate) and not certify:
+                # The primary key always certifies.
+                continue
+
+            res = ctx.create_key(make_uid(), algorithm="rsa",
+                                 sign=sign, encrypt=encrypt, certify=certify,
+                                 authenticate=authenticate)
+            key = ctx.get_key(res.fpr, secret=True)
+            assert key.fpr == res.fpr
+            assert len(key.subkeys) == 1, \
+                "Expected no subkey for non-default capabilities"
+
+            p = key.subkeys[0]
+            assert sign == p.can_sign
+            assert encrypt == p.can_encrypt
+            assert certify == p.can_certify
+            assert authenticate == p.can_authenticate
+
+        # Check algorithm
+        res = ctx.create_key(make_uid(), algorithm="rsa")
+        key = ctx.get_key(res.fpr, secret=True)
+        assert key.fpr == res.fpr
+        for k in key.subkeys:
+            assert k.pubkey_algo == 1
+
+        # Check algorithm with size
+        res = ctx.create_key(make_uid(), algorithm="rsa1024")
+        key = ctx.get_key(res.fpr, secret=True)
+        assert key.fpr == res.fpr
+        for k in key.subkeys:
+            assert k.pubkey_algo == 1
+            assert k.length == 1024
+
+        # Check algorithm future-default
+        ctx.create_key(make_uid(), algorithm="future-default")
+
+        # Check passphrase protection
+        recipient = make_uid()
+        passphrase = "streng geheim"
+        res = ctx.create_key(recipient, passphrase=passphrase)
+        ciphertext, _, _ = ctx.encrypt(b"hello there", recipients=[ctx.get_key(res.fpr)])
+
+        cb_called = False
+        def cb(*args):
+            global cb_called
+            cb_called = True
+            return passphrase
+        ctx.pinentry_mode = gpg.constants.PINENTRY_MODE_LOOPBACK
+        ctx.set_passphrase_cb(cb)
+
+        plaintext, _, _ = ctx.decrypt(ciphertext)
+        assert plaintext == b"hello there"
+        assert cb_called