1 /*
2 * Copyright (c) 2012 Intel Corporation. All Rights Reserved.
3 *
4 * Permission is hereby granted, free of charge, to any person obtaining a
5 * copy of this software and associated documentation files (the
6 * "Software"), to deal in the Software without restriction, including
7 * without limitation the rights to use, copy, modify, merge, publish,
8 * distribute, sub license, and/or sell copies of the Software, and to
9 * permit persons to whom the Software is furnished to do so, subject to
10 * the following conditions:
11 *
12 * The above copyright notice and this permission notice (including the
13 * next paragraph) shall be included in all copies or substantial portions
14 * of the Software.
15 *
16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
17 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
18 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.
19 * IN NO EVENT SHALL PRECISION INSIGHT AND/OR ITS SUPPLIERS BE LIABLE FOR
20 * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
21 * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
22 * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
23 */
24
25 #include "sysdeps.h"
26 #include <unistd.h>
27 #include <xf86drm.h>
28 #include "va_drm_auth.h"
29 #include "va_drm_auth_x11.h"
30
31 #if defined __linux__
32 # include <sys/syscall.h>
33 #endif
34
35 /* Checks whether the thread id is the current thread */
36 static bool
is_local_tid(pid_t tid)37 is_local_tid(pid_t tid)
38 {
39 #if defined __linux__
40 /* On Linux systems, drmGetClient() would return the thread ID
41 instead of the actual process ID */
42 return syscall(SYS_gettid) == tid;
43 #else
44 return false;
45 #endif
46 }
47
48 /* Checks whether DRM connection is authenticated */
49 bool
va_drm_is_authenticated(int fd)50 va_drm_is_authenticated(int fd)
51 {
52 pid_t client_pid;
53 int i, auth, pid, uid;
54 unsigned long magic, iocs;
55 bool is_authenticated = false;
56
57 client_pid = getpid();
58 for (i = 0; !is_authenticated; i++) {
59 if (drmGetClient(fd, i, &auth, &pid, &uid, &magic, &iocs) != 0)
60 break;
61 is_authenticated = auth && (pid == client_pid || is_local_tid(pid));
62 }
63 return is_authenticated;
64 }
65
66 /* Try to authenticate the DRM connection with the supplied magic id */
67 bool
va_drm_authenticate(int fd,uint32_t magic)68 va_drm_authenticate(int fd, uint32_t magic)
69 {
70 /* XXX: try to authenticate through Wayland, etc. */
71 #ifdef HAVE_VA_X11
72 if (va_drm_authenticate_x11(fd, magic))
73 return true;
74 #endif
75
76 /* Default: root + master privs are needed for the following call */
77 return drmAuthMagic(fd, magic) == 0;
78 }
79