g10: Improve and unify key selection for -r and --locate-keys.

* g10/getkey.c (struct pubkey_cmp_cookie): New type.
(key_is_ok, uid_is_ok, subkey_is_ok): New functions.
(pubkey_cmp): Likewise.
(get_best_pubkey_byname): Likewise.
* g10/keydb.h (get_best_pubkey_byname): New prototype.
* g10/keylist.c (locate_one): Use the new function.
* g10/pkclist.c (find_and_check_key): Likewise.
* tests/openpgp/Makefile.am (XTESTS): Add new test.
(TEST_FILES): Add new files.
* tests/openpgp/key-selection.scm: New file.
* tests/openpgp/key-selection/0.asc: Likewise.
* tests/openpgp/key-selection/1.asc: Likewise.
* tests/openpgp/key-selection/2.asc: Likewise.
* tests/openpgp/key-selection/3.asc: Likewise.
* tests/openpgp/key-selection/4.asc: Likewise.
--

When a name resembling a mail address is given to either --locate-keys
or --recipient, rank the search results and use only the most relevant
key.

This also lets us query which key will be used for encryption using
--locate-keys.  However, note that --locate-keys may also return keys
incapable of encryption, though it will prefer keys that have an
encryption subkey.

GnuPG-bug-id: 2359
Signed-off-by: Justus Winter <justus@g10code.com>

1 files changed, 82 insertions, 0 deletions

diff --git a/tests/openpgp/key-selection.scm b/tests/openpgp/key-selection.scm
new file mode 100644
index 000000000..536f60773
--- /dev/null
+++ b/tests/openpgp/key-selection.scm
@@ -0,0 +1,82 @@
+#!/usr/bin/env gpgscm
+
+;; Copyright (C) 2016 g10 Code GmbH
+;;
+;; This file is part of GnuPG.
+;;
+;; GnuPG 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.
+;;
+;; GnuPG 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/>.
+
+(load (with-path "defs.scm"))
+
+;; This test assumes a fixed time of 2004-01-01.
+
+ ;; Redefine gpg with a fixed time.
+(define gpg `(,@gpg --faked-system-time=1072911600))
+
+;; We have a number of keys for Mr. Acejlnu Acdipr <acdipr@example.org>.
+(define mailbox "acdipr@example.org")
+
+;; The keys are sorted, from the least relevant to the most relevant
+;; key.
+(define keys
+  '(("ED087E9D3394340738E20A244892A3CF8F65EBAC"
+     "no encryption-capable subkey, created: 2003-11-30, expires: 2006-11-29"
+     4)
+    ("D7388651A1B7466D03B538428178E04B0BAA385B"
+     "encryption-capable subkey, created: 2000-12-31, expired: 2001-12-31"
+     0)
+    ("DDEF1BEC66C8BAC8D69CED2AEABED840EC98B024"
+     "encryption-capable subkey, created: 2001-12-31, expires: 2006-12-30"
+     1)
+    ("03FCFEDE014027DD897AD2F23D32670A96A9C2BF"
+     "encryption-capable subkey, created: 2002-12-31, expires: 2005-12-30"
+     2)
+    ("B95BD6175CB6339244355BA160B8117E6119CED6"
+     "encryption-capable subkeys, last created: 2003-05-31, expires: 2005-05-30"
+     3)))
+
+;; Accessors for the elements of KEYS.
+(define :fpr car)
+(define :comment cadr)
+(define :number caddr)
+(define (:filename key)
+  (in-srcdir "key-selection"
+	     (string-append (number->string (:number key)) ".asc")))
+
+(define (delete-keys which)
+  (call-check `(,@gpg --delete-keys ,@(map :fpr which))))
+
+(define (import-keys which)
+  (call-check `(,@gpg --import ,@(map :filename which))))
+
+(for-each-p'
+ "Checking key selection"
+ (lambda (set)
+   (import-keys set)
+   (let ((fpr (list-ref (assoc "fpr"
+			       (gpg-with-colons `(--locate-key ,mailbox)))
+			9))
+	 (expected (:fpr (last set))))
+     (unless (equal? fpr expected)
+	     (display "Given keys ")
+	     (apply echo (map :fpr set))
+	     (echo "This is what --locate-key says:")
+	     (display (call-popen `(,@gpg --locate-key ,mailbox) ""))
+	     (echo "This is the key we expected:")
+	     (display (call-popen `(,@gpg --list-keys ,expected) ""))
+	     (error "Expected" expected "but got" fpr)))
+   (delete-keys set))
+ (lambda (set)
+   (length set))
+ (filter (lambda (x) (not (null? x))) (powerset keys)))