Commit | Line | Data |
---|---|---|
49052ec0 GM |
1 | ;;; password-cache.el --- Read passwords, possibly using a password cache. |
2 | ||
aa8f8277 GM |
3 | ;; Copyright (C) 1999, 2000, 2003, 2004, 2005, 2006, 2007, 2008, 2009, |
4 | ;; 2010 Free Software Foundation, Inc. | |
49052ec0 GM |
5 | |
6 | ;; Author: Simon Josefsson <simon@josefsson.org> | |
7 | ;; Created: 2003-12-21 | |
8 | ;; Keywords: password cache passphrase key | |
9 | ||
10 | ;; This file is part of GNU Emacs. | |
11 | ||
eb3fa2cf | 12 | ;; GNU Emacs is free software: you can redistribute it and/or modify |
49052ec0 | 13 | ;; it under the terms of the GNU General Public License as published by |
eb3fa2cf GM |
14 | ;; the Free Software Foundation, either version 3 of the License, or |
15 | ;; (at your option) any later version. | |
49052ec0 GM |
16 | |
17 | ;; GNU Emacs is distributed in the hope that it will be useful, | |
18 | ;; but WITHOUT ANY WARRANTY; without even the implied warranty of | |
19 | ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
20 | ;; GNU General Public License for more details. | |
21 | ||
22 | ;; You should have received a copy of the GNU General Public License | |
eb3fa2cf | 23 | ;; along with GNU Emacs. If not, see <http://www.gnu.org/licenses/>. |
49052ec0 GM |
24 | |
25 | ;;; Commentary: | |
26 | ||
27 | ;; Greatly influenced by pgg.el written by Daiki Ueno, with timer | |
28 | ;; fixes for XEmacs by Katsumi Yamaoka. In fact, this is mostly just | |
29 | ;; a rip-off. | |
30 | ;; | |
31 | ;; (password-read "Password? " "test") | |
32 | ;; ;; Minibuffer prompt for password. | |
33 | ;; => "foo" | |
34 | ;; | |
35 | ;; (password-cache-add "test" "foo") | |
36 | ;; => nil | |
37 | ||
49052ec0 GM |
38 | ;; (password-read "Password? " "test") |
39 | ;; ;; No minibuffer prompt | |
40 | ;; => "foo" | |
41 | ;; | |
42 | ;; (password-read "Password? " "test") | |
43 | ;; ;; No minibuffer prompt | |
44 | ;; => "foo" | |
45 | ;; | |
46 | ;; ;; Wait `password-cache-expiry' seconds. | |
47 | ;; | |
48 | ;; (password-read "Password? " "test") | |
49 | ;; ;; Minibuffer prompt for password is back. | |
50 | ;; => "foo" | |
51 | ||
52 | ;;; Code: | |
53 | ||
aa8f8277 GM |
54 | ;; Options are autoloaded since they are used by eg mml-sec.el. |
55 | ||
56 | ;;;###autoload | |
49052ec0 GM |
57 | (defcustom password-cache t |
58 | "Whether to cache passwords." | |
59 | :group 'password | |
60 | :type 'boolean) | |
61 | ||
aa8f8277 | 62 | ;;;###autoload |
49052ec0 GM |
63 | (defcustom password-cache-expiry 16 |
64 | "How many seconds passwords are cached, or nil to disable expiring. | |
65 | Whether passwords are cached at all is controlled by `password-cache'." | |
66 | :group 'password | |
67 | :type '(choice (const :tag "Never" nil) | |
68 | (integer :tag "Seconds"))) | |
69 | ||
70 | (defvar password-data (make-vector 7 0)) | |
71 | ||
72 | (defun password-read-from-cache (key) | |
73 | "Obtain passphrase for KEY from time-limited passphrase cache. | |
74 | Custom variables `password-cache' and `password-cache-expiry' | |
75 | regulate cache behavior." | |
76 | (and password-cache | |
77 | key | |
78 | (symbol-value (intern-soft key password-data)))) | |
79 | ||
80 | (defun password-read (prompt &optional key) | |
81 | "Read password, for use with KEY, from user, or from cache if wanted. | |
82 | KEY indicate the purpose of the password, so the cache can | |
83 | separate passwords. The cache is not used if KEY is nil. It is | |
84 | typically a string. | |
85 | The variable `password-cache' control whether the cache is used." | |
86 | (or (password-read-from-cache key) | |
87 | (read-passwd prompt))) | |
88 | ||
89 | (defun password-read-and-add (prompt &optional key) | |
90 | "Read password, for use with KEY, from user, or from cache if wanted. | |
91 | Then store the password in the cache. Uses `password-read' and | |
8b334673 GM |
92 | `password-cache-add'. Custom variables `password-cache' and |
93 | `password-cache-expiry' regulate cache behavior. | |
94 | ||
95 | Warning: the password is cached without checking that it is | |
96 | correct. It is better to check the password before caching. If | |
97 | you must use this function, take care to check passwords and | |
98 | remove incorrect ones from the cache." | |
49052ec0 GM |
99 | (let ((password (password-read prompt key))) |
100 | (when (and password key) | |
101 | (password-cache-add key password)) | |
102 | password)) | |
103 | ||
8b334673 GM |
104 | (make-obsolete 'password-read-and-add 'password-read "23.1") |
105 | ||
49052ec0 GM |
106 | (defun password-cache-remove (key) |
107 | "Remove password indexed by KEY from password cache. | |
8c4ec20f | 108 | This is typically run by a timer setup from `password-cache-add', |
49052ec0 GM |
109 | but can be invoked at any time to forcefully remove passwords |
110 | from the cache. This may be useful when it has been detected | |
111 | that a password is invalid, so that `password-read' query the | |
112 | user again." | |
113 | (let ((password (symbol-value (intern-soft key password-data)))) | |
114 | (when password | |
115 | (if (fboundp 'clear-string) | |
116 | (clear-string password) | |
117 | (fillarray password ?_)) | |
118 | (unintern key password-data)))) | |
119 | ||
120 | (defun password-cache-add (key password) | |
121 | "Add password to cache. | |
8b334673 | 122 | The password is removed by a timer after `password-cache-expiry' seconds." |
49052ec0 GM |
123 | (when (and password-cache-expiry (null (intern-soft key password-data))) |
124 | (run-at-time password-cache-expiry nil | |
125 | #'password-cache-remove | |
126 | key)) | |
127 | (set (intern key password-data) password) | |
128 | nil) | |
129 | ||
130 | (defun password-reset () | |
131 | "Clear the password cache." | |
132 | (interactive) | |
133 | (fillarray password-data 0)) | |
134 | ||
135 | (provide 'password-cache) | |
136 | ||
49052ec0 | 137 | ;;; password-cache.el ends here |