3 * IOCTLs for authentication
5 * \author Rickard E. (Rik) Faith <faith@valinux.com>
6 * \author Gareth Hughes <gareth@valinux.com>
10 * Created: Tue Feb 2 08:37:54 1999 by faith@valinux.com
12 * Copyright 1999 Precision Insight, Inc., Cedar Park, Texas.
13 * Copyright 2000 VA Linux Systems, Inc., Sunnyvale, California.
14 * All Rights Reserved.
16 * Permission is hereby granted, free of charge, to any person obtaining a
17 * copy of this software and associated documentation files (the "Software"),
18 * to deal in the Software without restriction, including without limitation
19 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
20 * and/or sell copies of the Software, and to permit persons to whom the
21 * Software is furnished to do so, subject to the following conditions:
23 * The above copyright notice and this permission notice (including the next
24 * paragraph) shall be included in all copies or substantial portions of the
27 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
28 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
29 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
30 * VA LINUX SYSTEMS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
31 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
32 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
33 * OTHER DEALINGS IN THE SOFTWARE.
39 * Find the file with the given magic number.
41 * \param dev DRM device.
42 * \param magic magic number.
44 * Searches in drm_device::magiclist within all files with the same hash key
45 * the one with matching magic number, while holding the drm_device::struct_mutex
48 static drm_file_t
*drm_find_file(drm_device_t
* dev
, drm_magic_t magic
)
50 drm_file_t
*retval
= NULL
;
51 drm_magic_entry_t
*pt
;
52 drm_hash_item_t
*hash
;
54 mutex_lock(&dev
->struct_mutex
);
55 if (!drm_ht_find_item(&dev
->magiclist
, (unsigned long)magic
, &hash
)) {
56 pt
= drm_hash_entry(hash
, drm_magic_entry_t
, hash_item
);
59 mutex_unlock(&dev
->struct_mutex
);
64 * Adds a magic number.
66 * \param dev DRM device.
67 * \param priv file private data.
68 * \param magic magic number.
70 * Creates a drm_magic_entry structure and appends to the linked list
71 * associated the magic number hash key in drm_device::magiclist, while holding
72 * the drm_device::struct_mutex lock.
74 static int drm_add_magic(drm_device_t
* dev
, drm_file_t
* priv
,
77 drm_magic_entry_t
*entry
;
79 DRM_DEBUG("%d\n", magic
);
81 entry
= drm_alloc(sizeof(*entry
), DRM_MEM_MAGIC
);
84 memset(entry
, 0, sizeof(*entry
));
87 entry
->hash_item
.key
= (unsigned long)magic
;
88 mutex_lock(&dev
->struct_mutex
);
89 drm_ht_insert_item(&dev
->magiclist
, &entry
->hash_item
);
90 list_add_tail(&entry
->head
, &dev
->magicfree
);
91 mutex_unlock(&dev
->struct_mutex
);
97 * Remove a magic number.
99 * \param dev DRM device.
100 * \param magic magic number.
102 * Searches and unlinks the entry in drm_device::magiclist with the magic
103 * number hash key, while holding the drm_device::struct_mutex lock.
105 static int drm_remove_magic(drm_device_t
* dev
, drm_magic_t magic
)
107 drm_magic_entry_t
*pt
;
108 drm_hash_item_t
*hash
;
110 DRM_DEBUG("%d\n", magic
);
112 mutex_lock(&dev
->struct_mutex
);
113 if (drm_ht_find_item(&dev
->magiclist
, (unsigned long)magic
, &hash
)) {
114 mutex_unlock(&dev
->struct_mutex
);
117 pt
= drm_hash_entry(hash
, drm_magic_entry_t
, hash_item
);
118 drm_ht_remove_item(&dev
->magiclist
, hash
);
120 mutex_unlock(&dev
->struct_mutex
);
122 drm_free(pt
, sizeof(*pt
), DRM_MEM_MAGIC
);
128 * Get a unique magic number (ioctl).
130 * \param inode device inode.
131 * \param filp file pointer.
132 * \param cmd command.
133 * \param arg pointer to a resulting drm_auth structure.
134 * \return zero on success, or a negative number on failure.
136 * If there is a magic number in drm_file::magic then use it, otherwise
137 * searches an unique non-zero magic number and add it associating it with \p
140 int drm_getmagic(struct inode
*inode
, struct file
*filp
,
141 unsigned int cmd
, unsigned long arg
)
143 static drm_magic_t sequence
= 0;
144 static DEFINE_SPINLOCK(lock
);
145 drm_file_t
*priv
= filp
->private_data
;
146 drm_device_t
*dev
= priv
->head
->dev
;
149 /* Find unique magic */
151 auth
.magic
= priv
->magic
;
156 ++sequence
; /* reserve 0 */
157 auth
.magic
= sequence
++;
159 } while (drm_find_file(dev
, auth
.magic
));
160 priv
->magic
= auth
.magic
;
161 drm_add_magic(dev
, priv
, auth
.magic
);
164 DRM_DEBUG("%u\n", auth
.magic
);
165 if (copy_to_user((drm_auth_t __user
*) arg
, &auth
, sizeof(auth
)))
171 * Authenticate with a magic.
173 * \param inode device inode.
174 * \param filp file pointer.
175 * \param cmd command.
176 * \param arg pointer to a drm_auth structure.
177 * \return zero if authentication successed, or a negative number otherwise.
179 * Checks if \p filp is associated with the magic number passed in \arg.
181 int drm_authmagic(struct inode
*inode
, struct file
*filp
,
182 unsigned int cmd
, unsigned long arg
)
184 drm_file_t
*priv
= filp
->private_data
;
185 drm_device_t
*dev
= priv
->head
->dev
;
189 if (copy_from_user(&auth
, (drm_auth_t __user
*) arg
, sizeof(auth
)))
191 DRM_DEBUG("%u\n", auth
.magic
);
192 if ((file
= drm_find_file(dev
, auth
.magic
))) {
193 file
->authenticated
= 1;
194 drm_remove_magic(dev
, auth
.magic
);