drivers/gpu/drm/drm_auth.c

   1 /*
   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  * Author Rickard E. (Rik) Faith <faith@valinux.com>
   9  * Author Gareth Hughes <gareth@valinux.com>
  10  *
  11  * Permission is hereby granted, free of charge, to any person obtaining a
  12  * copy of this software and associated documentation files (the "Software"),
  13  * to deal in the Software without restriction, including without limitation
  14  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  15  * and/or sell copies of the Software, and to permit persons to whom the
  16  * Software is furnished to do so, subject to the following conditions:
  17  *
  18  * The above copyright notice and this permission notice (including the next
  19  * paragraph) shall be included in all copies or substantial portions of the
  20  * Software.
  21  *
  22  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  23  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  24  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  25  * VA LINUX SYSTEMS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
  26  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
  27  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
  28  * OTHER DEALINGS IN THE SOFTWARE.
  29  */
  30
  31 #include <drm/drmP.h>
  32 #include "drm_internal.h"
  33
  34 /**
  35  * drm_getmagic - Get unique magic of a client
  36  * @dev: DRM device to operate on
  37  * @data: ioctl data containing the drm_auth object
  38  * @file_priv: DRM file that performs the operation
  39  *
  40  * This looks up the unique magic of the passed client and returns it. If the
  41  * client did not have a magic assigned, yet, a new one is registered. The magic
  42  * is stored in the passed drm_auth object.
  43  *
  44  * Returns: 0 on success, negative error code on failure.
  45  */
  46 int drm_getmagic(struct drm_device *dev, void *data, struct drm_file *file_priv)
  47 {
  48         struct drm_auth *auth = data;
  49         int ret = 0;
  50
  51         mutex_lock(&dev->struct_mutex);
  52         if (!file_priv->magic) {
  53                 ret = idr_alloc(&file_priv->master->magic_map, file_priv,
  54                                 1, 0, GFP_KERNEL);
  55                 if (ret >= 0)
  56                         file_priv->magic = ret;
  57         }
  58         auth->magic = file_priv->magic;
  59         mutex_unlock(&dev->struct_mutex);
  60
  61         DRM_DEBUG("%u\n", auth->magic);
  62
  63         return ret < 0 ? ret : 0;
  64 }
  65
  66 /**
  67  * drm_authmagic - Authenticate client with a magic
  68  * @dev: DRM device to operate on
  69  * @data: ioctl data containing the drm_auth object
  70  * @file_priv: DRM file that performs the operation
  71  *
  72  * This looks up a DRM client by the passed magic and authenticates it.
  73  *
  74  * Returns: 0 on success, negative error code on failure.
  75  */
  76 int drm_authmagic(struct drm_device *dev, void *data,
  77                   struct drm_file *file_priv)
  78 {
  79         struct drm_auth *auth = data;
  80         struct drm_file *file;
  81
  82         DRM_DEBUG("%u\n", auth->magic);
  83
  84         mutex_lock(&dev->struct_mutex);
  85         file = idr_find(&file_priv->master->magic_map, auth->magic);
  86         if (file) {
  87                 file->authenticated = 1;
  88                 idr_replace(&file_priv->master->magic_map, NULL, auth->magic);
  89         }
  90         mutex_unlock(&dev->struct_mutex);
  91
  92         return file ? 0 : -EINVAL;
  93 }