drm/linux-core/drm_auth.c

163 lines
4.4 KiB
C

/* drm_auth.h -- IOCTLs for authentication -*- linux-c -*-
* Created: Tue Feb 2 08:37:54 1999 by faith@valinux.com
*
* Copyright 1999 Precision Insight, Inc., Cedar Park, Texas.
* Copyright 2000 VA Linux Systems, Inc., Sunnyvale, California.
* All Rights Reserved.
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the "Software"),
* to deal in the Software without restriction, including without limitation
* the rights to use, copy, modify, merge, publish, distribute, sublicense,
* and/or sell copies of the Software, and to permit persons to whom the
* Software is furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice (including the next
* paragraph) shall be included in all copies or substantial portions of the
* Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* VA LINUX SYSTEMS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
* OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
* ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
* OTHER DEALINGS IN THE SOFTWARE.
*
* Authors:
* Rickard E. (Rik) Faith <faith@valinux.com>
* Gareth Hughes <gareth@valinux.com>
*/
#define __NO_VERSION__
#include "drmP.h"
static int DRM(hash_magic)(drm_magic_t magic)
{
return magic & (DRM_HASH_SIZE-1);
}
static drm_file_t *DRM(find_file)(drm_device_t *dev, drm_magic_t magic)
{
drm_file_t *retval = NULL;
drm_magic_entry_t *pt;
int hash = DRM(hash_magic)(magic);
down(&dev->struct_sem);
for (pt = dev->magiclist[hash].head; pt; pt = pt->next) {
if (pt->magic == magic) {
retval = pt->priv;
break;
}
}
up(&dev->struct_sem);
return retval;
}
int DRM(add_magic)(drm_device_t *dev, drm_file_t *priv, drm_magic_t magic)
{
int hash;
drm_magic_entry_t *entry;
DRM_DEBUG("%d\n", magic);
hash = DRM(hash_magic)(magic);
entry = DRM(alloc)(sizeof(*entry), DRM_MEM_MAGIC);
if (!entry) return -ENOMEM;
entry->magic = magic;
entry->priv = priv;
entry->next = NULL;
down(&dev->struct_sem);
if (dev->magiclist[hash].tail) {
dev->magiclist[hash].tail->next = entry;
dev->magiclist[hash].tail = entry;
} else {
dev->magiclist[hash].head = entry;
dev->magiclist[hash].tail = entry;
}
up(&dev->struct_sem);
return 0;
}
int DRM(remove_magic)(drm_device_t *dev, drm_magic_t magic)
{
drm_magic_entry_t *prev = NULL;
drm_magic_entry_t *pt;
int hash;
DRM_DEBUG("%d\n", magic);
hash = DRM(hash_magic)(magic);
down(&dev->struct_sem);
for (pt = dev->magiclist[hash].head; pt; prev = pt, pt = pt->next) {
if (pt->magic == magic) {
if (dev->magiclist[hash].head == pt) {
dev->magiclist[hash].head = pt->next;
}
if (dev->magiclist[hash].tail == pt) {
dev->magiclist[hash].tail = prev;
}
if (prev) {
prev->next = pt->next;
}
up(&dev->struct_sem);
return 0;
}
}
up(&dev->struct_sem);
DRM(free)(pt, sizeof(*pt), DRM_MEM_MAGIC);
return -EINVAL;
}
int DRM(getmagic)(struct inode *inode, struct file *filp,
unsigned int cmd, unsigned long arg)
{
static drm_magic_t sequence = 0;
static spinlock_t lock = SPIN_LOCK_UNLOCKED;
drm_file_t *priv = filp->private_data;
drm_device_t *dev = priv->dev;
drm_auth_t auth;
/* Find unique magic */
if (priv->magic) {
auth.magic = priv->magic;
} else {
do {
spin_lock(&lock);
if (!sequence) ++sequence; /* reserve 0 */
auth.magic = sequence++;
spin_unlock(&lock);
} while (DRM(find_file)(dev, auth.magic));
priv->magic = auth.magic;
DRM(add_magic)(dev, priv, auth.magic);
}
DRM_DEBUG("%u\n", auth.magic);
if (copy_to_user((drm_auth_t *)arg, &auth, sizeof(auth)))
return -EFAULT;
return 0;
}
int DRM(authmagic)(struct inode *inode, struct file *filp,
unsigned int cmd, unsigned long arg)
{
drm_file_t *priv = filp->private_data;
drm_device_t *dev = priv->dev;
drm_auth_t auth;
drm_file_t *file;
if (copy_from_user(&auth, (drm_auth_t *)arg, sizeof(auth)))
return -EFAULT;
DRM_DEBUG("%u\n", auth.magic);
if ((file = DRM(find_file)(dev, auth.magic))) {
file->authenticated = 1;
DRM(remove_magic)(dev, auth.magic);
return 0;
}
return -EINVAL;
}