2 * Copyright 1999 Precision Insight, Inc., Cedar Park, Texas.
3 * Copyright 2000 VA Linux Systems, Inc., Sunnyvale, California.
6 * Permission is hereby granted, free of charge, to any person obtaining a
7 * copy of this software and associated documentation files (the "Software"),
8 * to deal in the Software without restriction, including without limitation
9 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
10 * and/or sell copies of the Software, and to permit persons to whom the
11 * Software is furnished to do so, subject to the following conditions:
13 * The above copyright notice and this permission notice (including the next
14 * paragraph) shall be included in all copies or substantial portions of the
17 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
18 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
19 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
20 * VA LINUX SYSTEMS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
21 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
22 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
23 * OTHER DEALINGS IN THE SOFTWARE.
26 * Rickard E. (Rik) Faith <faith@valinux.com>
27 * Gareth Hughes <gareth@valinux.com>
29 * $FreeBSD: src/sys/dev/drm2/drm_auth.c,v 1.1 2012/05/22 11:07:44 kib Exp $
33 * Implementation of the get/authmagic ioctls implementing the authentication
34 * scheme between the master and clients.
39 static int drm_hash_magic(drm_magic_t magic)
41 return magic & (DRM_HASH_SIZE-1);
45 * Returns the file private associated with the given magic number.
47 static struct drm_file *drm_find_file(struct drm_device *dev, drm_magic_t magic)
49 drm_magic_entry_t *pt;
50 int hash = drm_hash_magic(magic);
54 for (pt = dev->magiclist[hash].head; pt; pt = pt->next) {
55 if (pt->magic == magic) {
64 * Inserts the given magic number into the hash table of used magic number
67 static int drm_add_magic(struct drm_device *dev, struct drm_file *priv,
71 drm_magic_entry_t *entry;
73 DRM_DEBUG("%d\n", magic);
77 hash = drm_hash_magic(magic);
78 entry = kmalloc(sizeof(*entry), DRM_MEM_MAGIC, M_ZERO | M_NOWAIT);
85 if (dev->magiclist[hash].tail) {
86 dev->magiclist[hash].tail->next = entry;
87 dev->magiclist[hash].tail = entry;
89 dev->magiclist[hash].head = entry;
90 dev->magiclist[hash].tail = entry;
97 * Removes the given magic number from the hash table of used magic number
100 static int drm_remove_magic(struct drm_device *dev, drm_magic_t magic)
102 drm_magic_entry_t *prev = NULL;
103 drm_magic_entry_t *pt;
106 DRM_LOCK_ASSERT(dev);
108 DRM_DEBUG("%d\n", magic);
109 hash = drm_hash_magic(magic);
111 for (pt = dev->magiclist[hash].head; pt; prev = pt, pt = pt->next) {
112 if (pt->magic == magic) {
113 if (dev->magiclist[hash].head == pt) {
114 dev->magiclist[hash].head = pt->next;
116 if (dev->magiclist[hash].tail == pt) {
117 dev->magiclist[hash].tail = prev;
120 prev->next = pt->next;
122 drm_free(pt, DRM_MEM_MAGIC);
131 * Called by the client, this returns a unique magic number to be authorized
134 * The master may use its own knowledge of the client (such as the X
135 * connection that the magic is passed over) to determine if the magic number
136 * should be authenticated.
138 int drm_getmagic(struct drm_device *dev, void *data, struct drm_file *file_priv)
140 static drm_magic_t sequence = 0;
141 struct drm_auth *auth = data;
143 /* Find unique magic */
144 if (file_priv->magic) {
145 auth->magic = file_priv->magic;
153 if (!atomic_cmpset_int(&sequence, old, auth->magic))
155 } while (drm_find_file(dev, auth->magic));
156 file_priv->magic = auth->magic;
157 drm_add_magic(dev, file_priv, auth->magic);
161 DRM_DEBUG("%u\n", auth->magic);
167 * Marks the client associated with the given magic number as authenticated.
169 int drm_authmagic(struct drm_device *dev, void *data,
170 struct drm_file *file_priv)
172 struct drm_auth *auth = data;
173 struct drm_file *priv;
175 DRM_DEBUG("%u\n", auth->magic);
178 priv = drm_find_file(dev, auth->magic);
180 priv->authenticated = 1;
181 drm_remove_magic(dev, auth->magic);