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 #define _GNU_SOURCE 1
26 #include "sysdeps.h"
27 #include <dlfcn.h>
28 #include <X11/Xlib.h>
29 #include "va_drm_auth_x11.h"
30 
31 #define LIBVA_MAJOR_VERSION 1
32 
33 typedef struct drm_auth_x11             DRMAuthX11;
34 typedef struct drm_auth_x11_vtable      DRMAuthX11VTable;
35 
36 typedef void (*VAGenericFunc)(void);
37 typedef Display *(*X11OpenDisplayFunc)(const char *display_name);
38 typedef int (*X11CloseDisplayFunc)(Display *display);
39 typedef Bool (*VADRI2QueryExtensionFunc)(
40     Display *display, int *event_base, int *error_base);
41 typedef Bool (*VADRI2QueryVersionFunc)(
42     Display *display, int *major, int *minor);
43 typedef Bool (*VADRI2AuthenticateFunc)(
44     Display *display, XID window, uint32_t magic);
45 
46 struct drm_auth_x11_vtable {
47     X11OpenDisplayFunc          x11_open_display;
48     X11CloseDisplayFunc         x11_close_display;
49     VADRI2QueryExtensionFunc    va_dri2_query_extension;
50     VADRI2QueryVersionFunc      va_dri2_query_version;
51     VADRI2AuthenticateFunc      va_dri2_authenticate;
52 };
53 
54 struct drm_auth_x11 {
55     void                       *handle; /* libva-x11.so.1 */
56     DRMAuthX11VTable            vtable;
57     Display                    *display;
58     Window                      window;
59 };
60 
61 static bool
get_symbol(void * handle,void * func_vptr,const char * name)62 get_symbol(void *handle, void *func_vptr, const char *name)
63 {
64     VAGenericFunc func, *func_ptr = func_vptr;
65     const char *error;
66 
67     dlerror();
68     func = (VAGenericFunc)dlsym(handle, name);
69     error = dlerror();
70 
71     if (error) {
72         fprintf(stderr, "error: failed to resolve %s() function: %s\n",
73                 name, error);
74         return false;
75     }
76 
77     *func_ptr = func;
78     return true;
79 }
80 
81 static bool
drm_auth_x11_init(DRMAuthX11 * auth)82 drm_auth_x11_init(DRMAuthX11 *auth)
83 {
84     struct drm_auth_x11_vtable *vtable;
85     char libva_x11_name[16];
86     int ret;
87 
88     ret = snprintf(
89         libva_x11_name, sizeof(libva_x11_name),
90         "libva-x11.so.%d", LIBVA_MAJOR_VERSION
91     );
92     if (ret < 0 || ret >= sizeof(libva_x11_name))
93         return false;
94 
95     auth->handle = dlopen(libva_x11_name, RTLD_LAZY | RTLD_GLOBAL);
96     if (!auth->handle) {
97         perror("open lib");
98         return false;
99     }
100 
101     vtable = &auth->vtable;
102     if (!get_symbol(RTLD_DEFAULT, &vtable->x11_open_display, "XOpenDisplay"))
103         return false;
104     if (!get_symbol(RTLD_DEFAULT, &vtable->x11_close_display, "XCloseDisplay"))
105         return false;
106     if (!get_symbol(auth->handle, &vtable->va_dri2_query_extension,
107                     "VA_DRI2QueryExtension"))
108         return false;
109     if (!get_symbol(auth->handle, &vtable->va_dri2_query_version,
110                     "VA_DRI2QueryVersion"))
111         return false;
112     if (!get_symbol(auth->handle, &vtable->va_dri2_authenticate,
113                     "VA_DRI2Authenticate"))
114         return false;
115 
116     auth->display = vtable->x11_open_display(NULL);
117     if (!auth->display)
118         return false;
119 
120     auth->window = DefaultRootWindow(auth->display);
121     return true;
122 }
123 
124 static void
drm_auth_x11_terminate(DRMAuthX11 * auth)125 drm_auth_x11_terminate(DRMAuthX11 *auth)
126 {
127     if (!auth)
128         return;
129 
130     if (auth->display) {
131         auth->vtable.x11_close_display(auth->display);
132         auth->display = NULL;
133         auth->window  = None;
134     }
135 
136     if (auth->handle) {
137         dlclose(auth->handle);
138         auth->handle = NULL;
139     }
140 }
141 
142 static bool
drm_auth_x11_authenticate(DRMAuthX11 * auth,int fd,uint32_t magic)143 drm_auth_x11_authenticate(DRMAuthX11 *auth, int fd, uint32_t magic)
144 {
145     DRMAuthX11VTable * const vtable = &auth->vtable;
146     int evt_base, err_base, v_major, v_minor;
147 
148     if (!vtable->va_dri2_query_extension(auth->display, &evt_base, &err_base))
149         return false;
150     if (!vtable->va_dri2_query_version(auth->display, &v_major, &v_minor))
151         return false;
152     if (!vtable->va_dri2_authenticate(auth->display, auth->window, magic))
153         return false;
154     return true;
155 }
156 
157 /* Try to authenticate the DRM connection with the supplied magic through X11 */
158 bool
va_drm_authenticate_x11(int fd,uint32_t magic)159 va_drm_authenticate_x11(int fd, uint32_t magic)
160 {
161     DRMAuthX11 auth;
162     bool success = false;
163 
164     memset(&auth, 0, sizeof(auth));
165     if (!drm_auth_x11_init(&auth))
166         goto end;
167     success = drm_auth_x11_authenticate(&auth, fd, magic);
168 
169 end:
170     drm_auth_x11_terminate(&auth);
171     return success;
172 }
173