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1 /*
2 * QEMU VNC display driver
3 *
4 * Copyright (C) 2006 Anthony Liguori <anthony@codemonkey.ws>
5 * Copyright (C) 2006 Fabrice Bellard
6 * Copyright (C) 2009 Red Hat, Inc
7 *
8 * Permission is hereby granted, free of charge, to any person obtaining a copy
9 * of this software and associated documentation files (the "Software"), to deal
10 * in the Software without restriction, including without limitation the rights
11 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
12 * copies of the Software, and to permit persons to whom the Software is
13 * furnished to do so, subject to the following conditions:
14 *
15 * The above copyright notice and this permission notice shall be included in
16 * all copies or substantial portions of the Software.
17 *
18 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
19 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
20 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
21 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
22 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
23 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
24 * THE SOFTWARE.
25 */
26
27 #ifndef __QEMU_VNC_H
28 #define __QEMU_VNC_H
29
30 #include "qemu-common.h"
31 #include "qemu/queue.h"
32 #include "qemu/thread.h"
33 #include "ui/console.h"
34 #include "monitor/monitor.h"
35 #include "audio/audio.h"
36 #include "qemu/bitmap.h"
37 #include <zlib.h>
38 #include <stdbool.h>
39
40 #include "keymaps.h"
41 #include "vnc-palette.h"
42 #include "vnc-enc-zrle.h"
43
44 // #define _VNC_DEBUG 1
45
46 #ifdef _VNC_DEBUG
47 #define VNC_DEBUG(fmt, ...) do { fprintf(stderr, fmt, ## __VA_ARGS__); } while (0)
48 #else
49 #define VNC_DEBUG(fmt, ...) do { } while (0)
50 #endif
51
52 /*****************************************************************************
53 *
54 * Core data structures
55 *
56 *****************************************************************************/
57
58 typedef struct Buffer
59 {
60 size_t capacity;
61 size_t offset;
62 uint8_t *buffer;
63 } Buffer;
64
65 typedef struct VncState VncState;
66 typedef struct VncJob VncJob;
67 typedef struct VncRect VncRect;
68 typedef struct VncRectEntry VncRectEntry;
69
70 typedef int VncReadEvent(VncState *vs, uint8_t *data, size_t len);
71
72 typedef void VncWritePixels(VncState *vs, void *data, int size);
73
74 typedef void VncSendHextileTile(VncState *vs,
75 int x, int y, int w, int h,
76 void *last_bg,
77 void *last_fg,
78 int *has_bg, int *has_fg);
79
80 /* VNC_MAX_WIDTH must be a multiple of 16. */
81 #define VNC_MAX_WIDTH 2560
82 #define VNC_MAX_HEIGHT 2048
83
84 /* VNC_DIRTY_BITS is the number of bits in the dirty bitmap. */
85 #define VNC_DIRTY_BITS (VNC_MAX_WIDTH / 16)
86
87 #define VNC_STAT_RECT 64
88 #define VNC_STAT_COLS (VNC_MAX_WIDTH / VNC_STAT_RECT)
89 #define VNC_STAT_ROWS (VNC_MAX_HEIGHT / VNC_STAT_RECT)
90
91 #define VNC_AUTH_CHALLENGE_SIZE 16
92
93 typedef struct VncDisplay VncDisplay;
94
95 #ifdef CONFIG_VNC_TLS
96 #include "vnc-tls.h"
97 #include "vnc-auth-vencrypt.h"
98 #endif
99 #ifdef CONFIG_VNC_SASL
100 #include "vnc-auth-sasl.h"
101 #endif
102 #ifdef CONFIG_VNC_WS
103 #include "vnc-ws.h"
104 #endif
105
106 struct VncRectStat
107 {
108 /* time of last 10 updates, to find update frequency */
109 struct timeval times[10];
110 int idx;
111
112 double freq; /* Update frequency (in Hz) */
113 bool updated; /* Already updated during this refresh */
114 };
115
116 typedef struct VncRectStat VncRectStat;
117
118 struct VncSurface
119 {
120 struct timeval last_freq_check;
121 DECLARE_BITMAP(dirty[VNC_MAX_HEIGHT], VNC_MAX_WIDTH / 16);
122 VncRectStat stats[VNC_STAT_ROWS][VNC_STAT_COLS];
123 pixman_image_t *fb;
124 pixman_format_code_t format;
125 };
126
127 typedef enum VncShareMode {
128 VNC_SHARE_MODE_CONNECTING = 1,
129 VNC_SHARE_MODE_SHARED,
130 VNC_SHARE_MODE_EXCLUSIVE,
131 VNC_SHARE_MODE_DISCONNECTED,
132 } VncShareMode;
133
134 typedef enum VncSharePolicy {
135 VNC_SHARE_POLICY_IGNORE = 1,
136 VNC_SHARE_POLICY_ALLOW_EXCLUSIVE,
137 VNC_SHARE_POLICY_FORCE_SHARED,
138 } VncSharePolicy;
139
140 struct VncDisplay
141 {
142 QTAILQ_HEAD(, VncState) clients;
143 int num_exclusive;
144 VncSharePolicy share_policy;
145 int lsock;
146 #ifdef CONFIG_VNC_WS
147 int lwebsock;
148 bool websocket;
149 char *ws_display;
150 #endif
151 DisplaySurface *ds;
152 DisplayChangeListener dcl;
153 kbd_layout_t *kbd_layout;
154 int lock_key_sync;
155 QemuMutex mutex;
156
157 QEMUCursor *cursor;
158 int cursor_msize;
159 uint8_t *cursor_mask;
160
161 struct VncSurface guest; /* guest visible surface (aka ds->surface) */
162 pixman_image_t *server; /* vnc server surface */
163
164 char *display;
165 char *password;
166 time_t expires;
167 int auth;
168 bool lossy;
169 bool non_adaptive;
170 #ifdef CONFIG_VNC_TLS
171 int subauth; /* Used by VeNCrypt */
172 VncDisplayTLS tls;
173 #endif
174 #ifdef CONFIG_VNC_SASL
175 VncDisplaySASL sasl;
176 #endif
177 };
178
179 typedef struct VncTight {
180 int type;
181 uint8_t quality;
182 uint8_t compression;
183 uint8_t pixel24;
184 Buffer tight;
185 Buffer tmp;
186 Buffer zlib;
187 Buffer gradient;
188 #ifdef CONFIG_VNC_JPEG
189 Buffer jpeg;
190 #endif
191 #ifdef CONFIG_VNC_PNG
192 Buffer png;
193 #endif
194 int levels[4];
195 z_stream stream[4];
196 } VncTight;
197
198 typedef struct VncHextile {
199 VncSendHextileTile *send_tile;
200 } VncHextile;
201
202 typedef struct VncZlib {
203 Buffer zlib;
204 Buffer tmp;
205 z_stream stream;
206 int level;
207 } VncZlib;
208
209 typedef struct VncZrle {
210 int type;
211 Buffer fb;
212 Buffer zrle;
213 Buffer tmp;
214 Buffer zlib;
215 z_stream stream;
216 VncPalette palette;
217 } VncZrle;
218
219 typedef struct VncZywrle {
220 int buf[VNC_ZRLE_TILE_WIDTH * VNC_ZRLE_TILE_HEIGHT];
221 } VncZywrle;
222
223 struct VncRect
224 {
225 int x;
226 int y;
227 int w;
228 int h;
229 };
230
231 struct VncRectEntry
232 {
233 struct VncRect rect;
234 QLIST_ENTRY(VncRectEntry) next;
235 };
236
237 struct VncJob
238 {
239 VncState *vs;
240
241 QLIST_HEAD(, VncRectEntry) rectangles;
242 QTAILQ_ENTRY(VncJob) next;
243 };
244
245 struct VncState
246 {
247 int csock;
248
249 DECLARE_BITMAP(dirty[VNC_MAX_HEIGHT], VNC_DIRTY_BITS);
250 uint8_t **lossy_rect; /* Not an Array to avoid costly memcpy in
251 * vnc-jobs-async.c */
252
253 VncDisplay *vd;
254 int need_update;
255 int force_update;
256 uint32_t features;
257 int absolute;
258 int last_x;
259 int last_y;
260 uint32_t last_bmask;
261 int client_width;
262 int client_height;
263 VncShareMode share_mode;
264
265 uint32_t vnc_encoding;
266
267 int major;
268 int minor;
269
270 int auth;
271 char challenge[VNC_AUTH_CHALLENGE_SIZE];
272 #ifdef CONFIG_VNC_TLS
273 int subauth; /* Used by VeNCrypt */
274 VncStateTLS tls;
275 #endif
276 #ifdef CONFIG_VNC_SASL
277 VncStateSASL sasl;
278 #endif
279 #ifdef CONFIG_VNC_WS
280 #ifdef CONFIG_VNC_TLS
281 VncStateTLS ws_tls;
282 #endif /* CONFIG_VNC_TLS */
283 bool encode_ws;
284 bool websocket;
285 #endif /* CONFIG_VNC_WS */
286
287 QObject *info;
288
289 Buffer output;
290 Buffer input;
291 #ifdef CONFIG_VNC_WS
292 Buffer ws_input;
293 Buffer ws_output;
294 #endif
295 /* current output mode information */
296 VncWritePixels *write_pixels;
297 PixelFormat client_pf;
298 pixman_format_code_t client_format;
299 bool client_be;
300
301 CaptureVoiceOut *audio_cap;
302 struct audsettings as;
303
304 VncReadEvent *read_handler;
305 size_t read_handler_expect;
306 /* input */
307 uint8_t modifiers_state[256];
308 QEMUPutLEDEntry *led;
309
310 bool abort;
311 bool initialized;
312 QemuMutex output_mutex;
313 QEMUBH *bh;
314 Buffer jobs_buffer;
315
316 /* Encoding specific, if you add something here, don't forget to
317 * update vnc_async_encoding_start()
318 */
319 VncTight tight;
320 VncZlib zlib;
321 VncHextile hextile;
322 VncZrle zrle;
323 VncZywrle zywrle;
324
325 Notifier mouse_mode_notifier;
326
327 QTAILQ_ENTRY(VncState) next;
328 };
329
330
331 /*****************************************************************************
332 *
333 * Authentication modes
334 *
335 *****************************************************************************/
336
337 enum {
338 VNC_AUTH_INVALID = 0,
339 VNC_AUTH_NONE = 1,
340 VNC_AUTH_VNC = 2,
341 VNC_AUTH_RA2 = 5,
342 VNC_AUTH_RA2NE = 6,
343 VNC_AUTH_TIGHT = 16,
344 VNC_AUTH_ULTRA = 17,
345 VNC_AUTH_TLS = 18, /* Supported in GTK-VNC & VINO */
346 VNC_AUTH_VENCRYPT = 19, /* Supported in GTK-VNC & VeNCrypt */
347 VNC_AUTH_SASL = 20, /* Supported in GTK-VNC & VINO */
348 };
349
350 enum {
351 VNC_AUTH_VENCRYPT_PLAIN = 256,
352 VNC_AUTH_VENCRYPT_TLSNONE = 257,
353 VNC_AUTH_VENCRYPT_TLSVNC = 258,
354 VNC_AUTH_VENCRYPT_TLSPLAIN = 259,
355 VNC_AUTH_VENCRYPT_X509NONE = 260,
356 VNC_AUTH_VENCRYPT_X509VNC = 261,
357 VNC_AUTH_VENCRYPT_X509PLAIN = 262,
358 VNC_AUTH_VENCRYPT_X509SASL = 263,
359 VNC_AUTH_VENCRYPT_TLSSASL = 264,
360 };
361
362
363 /*****************************************************************************
364 *
365 * Encoding types
366 *
367 *****************************************************************************/
368
369 #define VNC_ENCODING_RAW 0x00000000
370 #define VNC_ENCODING_COPYRECT 0x00000001
371 #define VNC_ENCODING_RRE 0x00000002
372 #define VNC_ENCODING_CORRE 0x00000004
373 #define VNC_ENCODING_HEXTILE 0x00000005
374 #define VNC_ENCODING_ZLIB 0x00000006
375 #define VNC_ENCODING_TIGHT 0x00000007
376 #define VNC_ENCODING_ZLIBHEX 0x00000008
377 #define VNC_ENCODING_TRLE 0x0000000f
378 #define VNC_ENCODING_ZRLE 0x00000010
379 #define VNC_ENCODING_ZYWRLE 0x00000011
380 #define VNC_ENCODING_COMPRESSLEVEL0 0xFFFFFF00 /* -256 */
381 #define VNC_ENCODING_QUALITYLEVEL0 0xFFFFFFE0 /* -32 */
382 #define VNC_ENCODING_XCURSOR 0xFFFFFF10 /* -240 */
383 #define VNC_ENCODING_RICH_CURSOR 0xFFFFFF11 /* -239 */
384 #define VNC_ENCODING_POINTER_POS 0xFFFFFF18 /* -232 */
385 #define VNC_ENCODING_LASTRECT 0xFFFFFF20 /* -224 */
386 #define VNC_ENCODING_DESKTOPRESIZE 0xFFFFFF21 /* -223 */
387 #define VNC_ENCODING_POINTER_TYPE_CHANGE 0XFFFFFEFF /* -257 */
388 #define VNC_ENCODING_EXT_KEY_EVENT 0XFFFFFEFE /* -258 */
389 #define VNC_ENCODING_AUDIO 0XFFFFFEFD /* -259 */
390 #define VNC_ENCODING_TIGHT_PNG 0xFFFFFEFC /* -260 */
391 #define VNC_ENCODING_LED_STATE 0XFFFFFEFB /* -261 */
392 #define VNC_ENCODING_WMVi 0x574D5669
393
394 /*****************************************************************************
395 *
396 * Other tight constants
397 *
398 *****************************************************************************/
399
400 /*
401 * Vendors known by TightVNC: standard VNC/RealVNC, TridiaVNC, and TightVNC.
402 */
403
404 #define VNC_TIGHT_CCB_RESET_MASK (0x0f)
405 #define VNC_TIGHT_CCB_TYPE_MASK (0x0f << 4)
406 #define VNC_TIGHT_CCB_TYPE_FILL (0x08 << 4)
407 #define VNC_TIGHT_CCB_TYPE_JPEG (0x09 << 4)
408 #define VNC_TIGHT_CCB_TYPE_PNG (0x0A << 4)
409 #define VNC_TIGHT_CCB_BASIC_MAX (0x07 << 4)
410 #define VNC_TIGHT_CCB_BASIC_ZLIB (0x03 << 4)
411 #define VNC_TIGHT_CCB_BASIC_FILTER (0x04 << 4)
412
413 /*****************************************************************************
414 *
415 * Features
416 *
417 *****************************************************************************/
418
419 #define VNC_FEATURE_RESIZE 0
420 #define VNC_FEATURE_HEXTILE 1
421 #define VNC_FEATURE_POINTER_TYPE_CHANGE 2
422 #define VNC_FEATURE_WMVI 3
423 #define VNC_FEATURE_TIGHT 4
424 #define VNC_FEATURE_ZLIB 5
425 #define VNC_FEATURE_COPYRECT 6
426 #define VNC_FEATURE_RICH_CURSOR 7
427 #define VNC_FEATURE_TIGHT_PNG 8
428 #define VNC_FEATURE_ZRLE 9
429 #define VNC_FEATURE_ZYWRLE 10
430 #define VNC_FEATURE_LED_STATE 11
431
432 #define VNC_FEATURE_RESIZE_MASK (1 << VNC_FEATURE_RESIZE)
433 #define VNC_FEATURE_HEXTILE_MASK (1 << VNC_FEATURE_HEXTILE)
434 #define VNC_FEATURE_POINTER_TYPE_CHANGE_MASK (1 << VNC_FEATURE_POINTER_TYPE_CHANGE)
435 #define VNC_FEATURE_WMVI_MASK (1 << VNC_FEATURE_WMVI)
436 #define VNC_FEATURE_TIGHT_MASK (1 << VNC_FEATURE_TIGHT)
437 #define VNC_FEATURE_ZLIB_MASK (1 << VNC_FEATURE_ZLIB)
438 #define VNC_FEATURE_COPYRECT_MASK (1 << VNC_FEATURE_COPYRECT)
439 #define VNC_FEATURE_RICH_CURSOR_MASK (1 << VNC_FEATURE_RICH_CURSOR)
440 #define VNC_FEATURE_TIGHT_PNG_MASK (1 << VNC_FEATURE_TIGHT_PNG)
441 #define VNC_FEATURE_ZRLE_MASK (1 << VNC_FEATURE_ZRLE)
442 #define VNC_FEATURE_ZYWRLE_MASK (1 << VNC_FEATURE_ZYWRLE)
443 #define VNC_FEATURE_LED_STATE_MASK (1 << VNC_FEATURE_LED_STATE)
444
445
446 /* Client -> Server message IDs */
447 #define VNC_MSG_CLIENT_SET_PIXEL_FORMAT 0
448 #define VNC_MSG_CLIENT_SET_ENCODINGS 2
449 #define VNC_MSG_CLIENT_FRAMEBUFFER_UPDATE_REQUEST 3
450 #define VNC_MSG_CLIENT_KEY_EVENT 4
451 #define VNC_MSG_CLIENT_POINTER_EVENT 5
452 #define VNC_MSG_CLIENT_CUT_TEXT 6
453 #define VNC_MSG_CLIENT_VMWARE_0 127
454 #define VNC_MSG_CLIENT_CALL_CONTROL 249
455 #define VNC_MSG_CLIENT_XVP 250
456 #define VNC_MSG_CLIENT_SET_DESKTOP_SIZE 251
457 #define VNC_MSG_CLIENT_TIGHT 252
458 #define VNC_MSG_CLIENT_GII 253
459 #define VNC_MSG_CLIENT_VMWARE_1 254
460 #define VNC_MSG_CLIENT_QEMU 255
461
462 /* Server -> Client message IDs */
463 #define VNC_MSG_SERVER_FRAMEBUFFER_UPDATE 0
464 #define VNC_MSG_SERVER_SET_COLOUR_MAP_ENTRIES 1
465 #define VNC_MSG_SERVER_BELL 2
466 #define VNC_MSG_SERVER_CUT_TEXT 3
467 #define VNC_MSG_SERVER_VMWARE_0 127
468 #define VNC_MSG_SERVER_CALL_CONTROL 249
469 #define VNC_MSG_SERVER_XVP 250
470 #define VNC_MSG_SERVER_TIGHT 252
471 #define VNC_MSG_SERVER_GII 253
472 #define VNC_MSG_SERVER_VMWARE_1 254
473 #define VNC_MSG_SERVER_QEMU 255
474
475
476
477 /* QEMU client -> server message IDs */
478 #define VNC_MSG_CLIENT_QEMU_EXT_KEY_EVENT 0
479 #define VNC_MSG_CLIENT_QEMU_AUDIO 1
480
481 /* QEMU server -> client message IDs */
482 #define VNC_MSG_SERVER_QEMU_AUDIO 1
483
484
485
486 /* QEMU client -> server audio message IDs */
487 #define VNC_MSG_CLIENT_QEMU_AUDIO_ENABLE 0
488 #define VNC_MSG_CLIENT_QEMU_AUDIO_DISABLE 1
489 #define VNC_MSG_CLIENT_QEMU_AUDIO_SET_FORMAT 2
490
491 /* QEMU server -> client audio message IDs */
492 #define VNC_MSG_SERVER_QEMU_AUDIO_END 0
493 #define VNC_MSG_SERVER_QEMU_AUDIO_BEGIN 1
494 #define VNC_MSG_SERVER_QEMU_AUDIO_DATA 2
495
496
497 /*****************************************************************************
498 *
499 * Internal APIs
500 *
501 *****************************************************************************/
502
503 /* Event loop functions */
504 void vnc_client_read(void *opaque);
505 void vnc_client_write(void *opaque);
506
507 long vnc_client_read_buf(VncState *vs, uint8_t *data, size_t datalen);
508 long vnc_client_write_buf(VncState *vs, const uint8_t *data, size_t datalen);
509
510 /* Protocol I/O functions */
511 void vnc_write(VncState *vs, const void *data, size_t len);
512 void vnc_write_u32(VncState *vs, uint32_t value);
513 void vnc_write_s32(VncState *vs, int32_t value);
514 void vnc_write_u16(VncState *vs, uint16_t value);
515 void vnc_write_u8(VncState *vs, uint8_t value);
516 void vnc_flush(VncState *vs);
517 void vnc_read_when(VncState *vs, VncReadEvent *func, size_t expecting);
518 void vnc_disconnect_finish(VncState *vs);
519 void vnc_init_state(VncState *vs);
520
521
522 /* Buffer I/O functions */
523 uint32_t read_u32(uint8_t *data, size_t offset);
524
525 /* Protocol stage functions */
526 void vnc_client_error(VncState *vs);
527 int vnc_client_io_error(VncState *vs, int ret, int last_errno);
528
529 void start_client_init(VncState *vs);
530 void start_auth_vnc(VncState *vs);
531
532 /* Buffer management */
533 void buffer_reserve(Buffer *buffer, size_t len);
534 void buffer_reset(Buffer *buffer);
535 void buffer_free(Buffer *buffer);
536 void buffer_append(Buffer *buffer, const void *data, size_t len);
537 void buffer_advance(Buffer *buf, size_t len);
538 uint8_t *buffer_end(Buffer *buffer);
539
540
541 /* Misc helpers */
542
543 char *vnc_socket_local_addr(const char *format, int fd);
544 char *vnc_socket_remote_addr(const char *format, int fd);
545
546 static inline uint32_t vnc_has_feature(VncState *vs, int feature) {
547 return (vs->features & (1 << feature));
548 }
549
550 /* Framebuffer */
551 void vnc_framebuffer_update(VncState *vs, int x, int y, int w, int h,
552 int32_t encoding);
553
554 /* server fb is in PIXMAN_x8r8g8b8 */
555 #define VNC_SERVER_FB_FORMAT PIXMAN_FORMAT(32, PIXMAN_TYPE_ARGB, 0, 8, 8, 8)
556 #define VNC_SERVER_FB_BITS (PIXMAN_FORMAT_BPP(VNC_SERVER_FB_FORMAT))
557 #define VNC_SERVER_FB_BYTES ((VNC_SERVER_FB_BITS+7)/8)
558
559 void *vnc_server_fb_ptr(VncDisplay *vd, int x, int y);
560 int vnc_server_fb_stride(VncDisplay *vd);
561
562 void vnc_convert_pixel(VncState *vs, uint8_t *buf, uint32_t v);
563 double vnc_update_freq(VncState *vs, int x, int y, int w, int h);
564 void vnc_sent_lossy_rect(VncState *vs, int x, int y, int w, int h);
565
566 /* Encodings */
567 int vnc_send_framebuffer_update(VncState *vs, int x, int y, int w, int h);
568
569 int vnc_raw_send_framebuffer_update(VncState *vs, int x, int y, int w, int h);
570
571 int vnc_hextile_send_framebuffer_update(VncState *vs, int x,
572 int y, int w, int h);
573 void vnc_hextile_set_pixel_conversion(VncState *vs, int generic);
574
575 void *vnc_zlib_zalloc(void *x, unsigned items, unsigned size);
576 void vnc_zlib_zfree(void *x, void *addr);
577 int vnc_zlib_send_framebuffer_update(VncState *vs, int x, int y, int w, int h);
578 void vnc_zlib_clear(VncState *vs);
579
580 int vnc_tight_send_framebuffer_update(VncState *vs, int x, int y, int w, int h);
581 int vnc_tight_png_send_framebuffer_update(VncState *vs, int x, int y,
582 int w, int h);
583 void vnc_tight_clear(VncState *vs);
584
585 int vnc_zrle_send_framebuffer_update(VncState *vs, int x, int y, int w, int h);
586 int vnc_zywrle_send_framebuffer_update(VncState *vs, int x, int y, int w, int h);
587 void vnc_zrle_clear(VncState *vs);
588
589 #endif /* __QEMU_VNC_H */