linux-kernel - [PATCH] Let keyboard notifiers modify key codes

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Date:	Wed, 7 Jan 2009 01:58:13 +0100
From:	Samuel Thibault <samuel.thibault@...-lyon.org>
To:	linux-kernel@...r.kernel.org
Cc:	akpm@...ux-foundation.org, dmitry.torokhov@...il.com,
	linux-input@...r.kernel.org
Subject: [PATCH] Let keyboard notifiers modify key codes

Make kbd_keycode() read param.value after calling the keyboard notification
chain, to let the callee change the translation on the fly. This for instance
permits to remap the physical positions of the keys independently of the
configured keymap, for e.g. single-handed people.

Signed-off-by: Samuel Thibault <samuel.thibault@...-lyon.org>

--- linux/drivers/char/keyboard.c.orig	2009-01-07 00:48:46.000000000 +0100
+++ linux/drivers/char/keyboard.c	2009-01-07 01:02:05.000000000 +0100
@@ -1248,6 +1248,7 @@ kbd_keycode
 		kbd->slockstate = 0;
 		return;
 	}
+	keycode = param.value;
 
 	if (keycode >= NR_KEYS)
 		if (keycode >= KEY_BRL_DOT1 && keycode <= KEY_BRL_DOT8)
@@ -1263,6 +1264,7 @@ kbd_keycode
 		param.value = keysym;
 		if (atomic_notifier_call_chain(&keyboard_notifier_list, KBD_UNICODE, &param) == NOTIFY_STOP)
 			return;
+		keysym = param.value;
 		if (down && !raw_mode)
 			to_utf8(vc, keysym);
 		return;
@@ -1282,6 +1284,7 @@ kbd_keycode
 
 	if (atomic_notifier_call_chain(&keyboard_notifier_list, KBD_KEYSYM, &param) == NOTIFY_STOP)
 		return;
+	keysym = param.value;
 
 	if (raw_mode && type != KT_SPEC && type != KT_SHIFT)
 		return;
--- linux/Documentation/input/notifier.txt.orig	2008-04-17 12:14:30.000000000 +0200
+++ linux/Documentation/input/notifier.txt	2009-01-07 01:04:16.000000000 +0100
@@ -21,7 +21,8 @@
 
 For each kind of event but the last, the callback may return NOTIFY_STOP in
 order to "eat" the event: the notify loop is stopped and the keyboard event is
-dropped.
+dropped.  The callee can also modify param.value so as to change the key
+translation.
 
 In a rough C snippet, we have:
 
@@ -33,18 +34,26 @@
 		notifier_call_chain(KBD_UNBOUND_KEYCODE,&params);
 		return;
 	}
+	keycode = param.value;
+
+	...
 
 	if (unicode) {
 		param.value = unicode;
 		if (notifier_call_chain(KBD_UNICODE,&params) == NOTIFY_STOP)
 			return;
+		keysym = param.value;
 		emit unicode;
 		return;
 	}
 
+	...
+
 	params.value = keysym;
 	if (notifier_call_chain(KBD_KEYSYM,&params) == NOTIFY_STOP)
 		return;
+	keysym = params.value;
+
 	apply keysym;
 	notifier_call_chain(KBD_POST_KEYSYM,&params);
 }
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/