1 /* $NetBSD: drm_auth.c,v 1.4 2018/08/27 14:14:29 riastradh Exp $ */ 2 3 /* 4 * Created: Tue Feb 2 08:37:54 1999 by faith@valinux.com 5 * 6 * Copyright 1999 Precision Insight, Inc., Cedar Park, Texas. 7 * Copyright 2000 VA Linux Systems, Inc., Sunnyvale, California. 8 * All Rights Reserved. 9 * 10 * Author Rickard E. (Rik) Faith <faith@valinux.com> 11 * Author Gareth Hughes <gareth@valinux.com> 12 * 13 * Permission is hereby granted, free of charge, to any person obtaining a 14 * copy of this software and associated documentation files (the "Software"), 15 * to deal in the Software without restriction, including without limitation 16 * the rights to use, copy, modify, merge, publish, distribute, sublicense, 17 * and/or sell copies of the Software, and to permit persons to whom the 18 * Software is furnished to do so, subject to the following conditions: 19 * 20 * The above copyright notice and this permission notice (including the next 21 * paragraph) shall be included in all copies or substantial portions of the 22 * Software. 23 * 24 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 25 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 26 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL 27 * VA LINUX SYSTEMS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR 28 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, 29 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR 30 * OTHER DEALINGS IN THE SOFTWARE. 31 */ 32 33 #include <sys/cdefs.h> 34 __KERNEL_RCSID(0, "$NetBSD: drm_auth.c,v 1.4 2018/08/27 14:14:29 riastradh Exp $"); 35 36 #include <drm/drmP.h> 37 #include "drm_internal.h" 38 39 /** 40 * drm_getmagic - Get unique magic of a client 41 * @dev: DRM device to operate on 42 * @data: ioctl data containing the drm_auth object 43 * @file_priv: DRM file that performs the operation 44 * 45 * This looks up the unique magic of the passed client and returns it. If the 46 * client did not have a magic assigned, yet, a new one is registered. The magic 47 * is stored in the passed drm_auth object. 48 * 49 * Returns: 0 on success, negative error code on failure. 50 */ 51 int drm_getmagic(struct drm_device *dev, void *data, struct drm_file *file_priv) 52 { 53 struct drm_auth *auth = data; 54 int ret = 0; 55 56 idr_preload(GFP_KERNEL); 57 mutex_lock(&dev->struct_mutex); 58 if (!file_priv->magic) { 59 ret = idr_alloc(&file_priv->master->magic_map, file_priv, 60 1, 0, GFP_KERNEL); 61 if (ret >= 0) 62 file_priv->magic = ret; 63 } 64 auth->magic = file_priv->magic; 65 mutex_unlock(&dev->struct_mutex); 66 idr_preload_end(); 67 68 DRM_DEBUG("%u\n", auth->magic); 69 70 return ret < 0 ? ret : 0; 71 } 72 73 /** 74 * drm_authmagic - Authenticate client with a magic 75 * @dev: DRM device to operate on 76 * @data: ioctl data containing the drm_auth object 77 * @file_priv: DRM file that performs the operation 78 * 79 * This looks up a DRM client by the passed magic and authenticates it. 80 * 81 * Returns: 0 on success, negative error code on failure. 82 */ 83 int drm_authmagic(struct drm_device *dev, void *data, 84 struct drm_file *file_priv) 85 { 86 struct drm_auth *auth = data; 87 struct drm_file *file; 88 89 DRM_DEBUG("%u\n", auth->magic); 90 91 mutex_lock(&dev->struct_mutex); 92 file = idr_find(&file_priv->master->magic_map, auth->magic); 93 if (file) { 94 file->authenticated = 1; 95 idr_replace(&file_priv->master->magic_map, NULL, auth->magic); 96 } 97 mutex_unlock(&dev->struct_mutex); 98 99 return file ? 0 : -EINVAL; 100 } 101