sys/dev/drm/drm_auth.h

   1 /* drm_auth.h -- IOCTLs for authentication -*- linux-c -*-
   2  * Created: Tue Feb  2 08:37:54 1999 by faith@valinux.com
   3  *
   4  * Copyright 1999 Precision Insight, Inc., Cedar Park, Texas.
   5  * Copyright 2000 VA Linux Systems, Inc., Sunnyvale, California.
   6  * All Rights Reserved.
   7  *
   8  * Permission is hereby granted, free of charge, to any person obtaining a
   9  * copy of this software and associated documentation files (the "Software"),
  10  * to deal in the Software without restriction, including without limitation
  11  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  12  * and/or sell copies of the Software, and to permit persons to whom the
  13  * Software is furnished to do so, subject to the following conditions:
  14  *
  15  * The above copyright notice and this permission notice (including the next
  16  * paragraph) shall be included in all copies or substantial portions of the
  17  * Software.
  18  *
  19  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  20  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  21  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  22  * VA LINUX SYSTEMS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
  23  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
  24  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
  25  * OTHER DEALINGS IN THE SOFTWARE.
  26  *
  27  * Authors:
  28  *    Rickard E. (Rik) Faith <faith@valinux.com>
  29  *    Gareth Hughes <gareth@valinux.com>
  30  * $FreeBSD: src/sys/dev/drm/drm_auth.h,v 1.3.2.1 2003/04/26 07:05:28 anholt Exp $
  31  * $DragonFly: src/sys/dev/drm/drm_auth.h,v 1.2 2003/06/17 06:28:24 dillon Exp $
  32  */
  33
  34 #include "dev/drm/drmP.h"
  35
  36 static int DRM(hash_magic)(drm_magic_t magic)
  37 {
  38         return magic & (DRM_HASH_SIZE-1);
  39 }
  40
  41 static drm_file_t *DRM(find_file)(drm_device_t *dev, drm_magic_t magic)
  42 {
  43         drm_file_t        *retval = NULL;
  44         drm_magic_entry_t *pt;
  45         int               hash    = DRM(hash_magic)(magic);
  46
  47         DRM_LOCK;
  48         for (pt = dev->magiclist[hash].head; pt; pt = pt->next) {
  49                 if (pt->magic == magic) {
  50                         retval = pt->priv;
  51                         break;
  52                 }
  53         }
  54         DRM_UNLOCK;
  55         return retval;
  56 }
  57
  58 int DRM(add_magic)(drm_device_t *dev, drm_file_t *priv, drm_magic_t magic)
  59 {
  60         int               hash;
  61         drm_magic_entry_t *entry;
  62
  63         DRM_DEBUG("%d\n", magic);
  64
  65         hash         = DRM(hash_magic)(magic);
  66         entry        = (drm_magic_entry_t*) DRM(alloc)(sizeof(*entry), DRM_MEM_MAGIC);
  67         if (!entry) return DRM_ERR(ENOMEM);
  68         memset(entry, 0, sizeof(*entry));
  69         entry->magic = magic;
  70         entry->priv  = priv;
  71         entry->next  = NULL;
  72
  73         DRM_LOCK;
  74         if (dev->magiclist[hash].tail) {
  75                 dev->magiclist[hash].tail->next = entry;
  76                 dev->magiclist[hash].tail       = entry;
  77         } else {
  78                 dev->magiclist[hash].head       = entry;
  79                 dev->magiclist[hash].tail       = entry;
  80         }
  81         DRM_UNLOCK;
  82
  83         return 0;
  84 }
  85
  86 int DRM(remove_magic)(drm_device_t *dev, drm_magic_t magic)
  87 {
  88         drm_magic_entry_t *prev = NULL;
  89         drm_magic_entry_t *pt;
  90         int               hash;
  91
  92         DRM_DEBUG("%d\n", magic);
  93         hash = DRM(hash_magic)(magic);
  94
  95         DRM_LOCK;
  96         for (pt = dev->magiclist[hash].head; pt; prev = pt, pt = pt->next) {
  97                 if (pt->magic == magic) {
  98                         if (dev->magiclist[hash].head == pt) {
  99                                 dev->magiclist[hash].head = pt->next;
 100                         }
 101                         if (dev->magiclist[hash].tail == pt) {
 102                                 dev->magiclist[hash].tail = prev;
 103                         }
 104                         if (prev) {
 105                                 prev->next = pt->next;
 106                         }
 107                         DRM_UNLOCK;
 108                         return 0;
 109                 }
 110         }
 111         DRM_UNLOCK;
 112
 113         DRM(free)(pt, sizeof(*pt), DRM_MEM_MAGIC);
 114         return DRM_ERR(EINVAL);
 115 }
 116
 117 int DRM(getmagic)(DRM_IOCTL_ARGS)
 118 {
 119         static drm_magic_t sequence = 0;
 120         drm_auth_t         auth;
 121         DRM_DEVICE;
 122         DRM_PRIV;
 123
 124                                 /* Find unique magic */
 125         if (priv->magic) {
 126                 auth.magic = priv->magic;
 127         } else {
 128                 do {
 129                         int old = sequence;
 130
 131                         auth.magic = old+1;
 132
 133                         if (!atomic_cmpset_int(&sequence, old, auth.magic))
 134                                 continue;
 135                 } while (DRM(find_file)(dev, auth.magic));
 136                 priv->magic = auth.magic;
 137                 DRM(add_magic)(dev, priv, auth.magic);
 138         }
 139
 140         DRM_DEBUG("%u\n", auth.magic);
 141
 142         DRM_COPY_TO_USER_IOCTL((drm_auth_t *)data, auth, sizeof(auth));
 143
 144         return 0;
 145 }
 146
 147 int DRM(authmagic)(DRM_IOCTL_ARGS)
 148 {
 149         drm_auth_t         auth;
 150         drm_file_t         *file;
 151         DRM_DEVICE;
 152
 153         DRM_COPY_FROM_USER_IOCTL(auth, (drm_auth_t *)data, sizeof(auth));
 154
 155         DRM_DEBUG("%u\n", auth.magic);
 156         if ((file = DRM(find_file)(dev, auth.magic))) {
 157                 file->authenticated = 1;
 158                 DRM(remove_magic)(dev, auth.magic);
 159                 return 0;
 160         }
 161         return DRM_ERR(EINVAL);
 162 }