slock.c (11790B)
1 /* See LICENSE file for license details. */ 2 #define _XOPEN_SOURCE 500 3 #if HAVE_SHADOW_H 4 #include <shadow.h> 5 #endif 6 7 #include <ctype.h> 8 #include <errno.h> 9 #include <grp.h> 10 #include <pwd.h> 11 #include <stdarg.h> 12 #include <stdlib.h> 13 #include <stdio.h> 14 #include <string.h> 15 #include <unistd.h> 16 #include <sys/types.h> 17 #include <X11/extensions/Xrandr.h> 18 #include <X11/keysym.h> 19 #include <X11/Xlib.h> 20 #include <X11/Xutil.h> 21 #include <Imlib2.h> 22 23 #include "arg.h" 24 #include "util.h" 25 26 char *argv0; 27 28 enum { 29 INIT, 30 INPUT, 31 FAILED, 32 NUMCOLS 33 }; 34 35 struct lock { 36 int screen; 37 Window root, win; 38 Pixmap pmap; 39 Pixmap bgmap; 40 unsigned long colors[NUMCOLS]; 41 }; 42 43 struct xrandr { 44 int active; 45 int evbase; 46 int errbase; 47 }; 48 49 #include "config.h" 50 51 Imlib_Image image; 52 53 static void 54 die(const char *errstr, ...) 55 { 56 va_list ap; 57 58 va_start(ap, errstr); 59 vfprintf(stderr, errstr, ap); 60 va_end(ap); 61 exit(1); 62 } 63 64 #ifdef __linux__ 65 #include <fcntl.h> 66 #include <linux/oom.h> 67 68 static void 69 dontkillme(void) 70 { 71 FILE *f; 72 const char oomfile[] = "/proc/self/oom_score_adj"; 73 74 if (!(f = fopen(oomfile, "w"))) { 75 if (errno == ENOENT) 76 return; 77 die("slock: fopen %s: %s\n", oomfile, strerror(errno)); 78 } 79 fprintf(f, "%d", OOM_SCORE_ADJ_MIN); 80 if (fclose(f)) { 81 if (errno == EACCES) 82 die("slock: unable to disable OOM killer. " 83 "Make sure to suid or sgid slock.\n"); 84 else 85 die("slock: fclose %s: %s\n", oomfile, strerror(errno)); 86 } 87 } 88 #endif 89 90 static const char * 91 gethash(void) 92 { 93 const char *hash; 94 struct passwd *pw; 95 96 /* Check if the current user has a password entry */ 97 errno = 0; 98 if (!(pw = getpwuid(getuid()))) { 99 if (errno) 100 die("slock: getpwuid: %s\n", strerror(errno)); 101 else 102 die("slock: cannot retrieve password entry\n"); 103 } 104 hash = pw->pw_passwd; 105 106 #if HAVE_SHADOW_H 107 if (!strcmp(hash, "x")) { 108 struct spwd *sp; 109 if (!(sp = getspnam(pw->pw_name))) 110 die("slock: getspnam: cannot retrieve shadow entry. " 111 "Make sure to suid or sgid slock.\n"); 112 hash = sp->sp_pwdp; 113 } 114 #else 115 if (!strcmp(hash, "*")) { 116 #ifdef __OpenBSD__ 117 if (!(pw = getpwuid_shadow(getuid()))) 118 die("slock: getpwnam_shadow: cannot retrieve shadow entry. " 119 "Make sure to suid or sgid slock.\n"); 120 hash = pw->pw_passwd; 121 #else 122 die("slock: getpwuid: cannot retrieve shadow entry. " 123 "Make sure to suid or sgid slock.\n"); 124 #endif /* __OpenBSD__ */ 125 } 126 #endif /* HAVE_SHADOW_H */ 127 128 return hash; 129 } 130 131 static void 132 readpw(Display *dpy, struct xrandr *rr, struct lock **locks, int nscreens, 133 const char *hash) 134 { 135 XRRScreenChangeNotifyEvent *rre; 136 char buf[32], passwd[256], *inputhash; 137 int num, screen, running, failure, oldc; 138 unsigned int len, color; 139 KeySym ksym; 140 XEvent ev; 141 142 len = 0; 143 running = 1; 144 failure = 0; 145 oldc = INIT; 146 147 while (running && !XNextEvent(dpy, &ev)) { 148 if (ev.type == KeyPress) { 149 explicit_bzero(&buf, sizeof(buf)); 150 num = XLookupString(&ev.xkey, buf, sizeof(buf), &ksym, 0); 151 if (IsKeypadKey(ksym)) { 152 if (ksym == XK_KP_Enter) 153 ksym = XK_Return; 154 else if (ksym >= XK_KP_0 && ksym <= XK_KP_9) 155 ksym = (ksym - XK_KP_0) + XK_0; 156 } 157 if (IsFunctionKey(ksym) || 158 IsKeypadKey(ksym) || 159 IsMiscFunctionKey(ksym) || 160 IsPFKey(ksym) || 161 IsPrivateKeypadKey(ksym)) 162 continue; 163 switch (ksym) { 164 case XK_Return: 165 passwd[len] = '\0'; 166 errno = 0; 167 if (!(inputhash = crypt(passwd, hash))) 168 fprintf(stderr, "slock: crypt: %s\n", strerror(errno)); 169 else 170 running = !!strcmp(inputhash, hash); 171 if (running) { 172 XBell(dpy, 100); 173 failure = 1; 174 } 175 explicit_bzero(&passwd, sizeof(passwd)); 176 len = 0; 177 break; 178 case XK_Escape: 179 explicit_bzero(&passwd, sizeof(passwd)); 180 len = 0; 181 break; 182 case XK_BackSpace: 183 if (len) 184 passwd[--len] = '\0'; 185 break; 186 default: 187 if (num && !iscntrl((int)buf[0]) && 188 (len + num < sizeof(passwd))) { 189 memcpy(passwd + len, buf, num); 190 len += num; 191 } 192 break; 193 } 194 color = len ? INPUT : ((failure || failonclear) ? FAILED : INIT); 195 if (running && oldc != color) { 196 for (screen = 0; screen < nscreens; screen++) { 197 if(locks[screen]->bgmap) 198 XSetWindowBackgroundPixmap(dpy, locks[screen]->win, locks[screen]->bgmap); 199 else 200 XSetWindowBackground(dpy, locks[screen]->win, locks[screen]->colors[0]); 201 XClearWindow(dpy, locks[screen]->win); 202 } 203 oldc = color; 204 } 205 } else if (rr->active && ev.type == rr->evbase + RRScreenChangeNotify) { 206 rre = (XRRScreenChangeNotifyEvent*)&ev; 207 for (screen = 0; screen < nscreens; screen++) { 208 if (locks[screen]->win == rre->window) { 209 if (rre->rotation == RR_Rotate_90 || 210 rre->rotation == RR_Rotate_270) 211 XResizeWindow(dpy, locks[screen]->win, 212 rre->height, rre->width); 213 else 214 XResizeWindow(dpy, locks[screen]->win, 215 rre->width, rre->height); 216 XClearWindow(dpy, locks[screen]->win); 217 break; 218 } 219 } 220 } else { 221 for (screen = 0; screen < nscreens; screen++) 222 XRaiseWindow(dpy, locks[screen]->win); 223 } 224 } 225 } 226 227 static struct lock * 228 lockscreen(Display *dpy, struct xrandr *rr, int screen) 229 { 230 char curs[] = {0, 0, 0, 0, 0, 0, 0, 0}; 231 int i, ptgrab, kbgrab; 232 struct lock *lock; 233 XColor color, dummy; 234 XSetWindowAttributes wa; 235 Cursor invisible; 236 237 if (dpy == NULL || screen < 0 || !(lock = malloc(sizeof(struct lock)))) 238 return NULL; 239 240 lock->screen = screen; 241 lock->root = RootWindow(dpy, lock->screen); 242 243 if(image) 244 { 245 lock->bgmap = XCreatePixmap(dpy, lock->root, DisplayWidth(dpy, lock->screen), DisplayHeight(dpy, lock->screen), DefaultDepth(dpy, lock->screen)); 246 imlib_context_set_image(image); 247 imlib_context_set_display(dpy); 248 imlib_context_set_visual(DefaultVisual(dpy, lock->screen)); 249 imlib_context_set_colormap(DefaultColormap(dpy, lock->screen)); 250 imlib_context_set_drawable(lock->bgmap); 251 imlib_render_image_on_drawable(0, 0); 252 imlib_free_image(); 253 } 254 for (i = 0; i < NUMCOLS; i++) { 255 XAllocNamedColor(dpy, DefaultColormap(dpy, lock->screen), 256 colorname[i], &color, &dummy); 257 lock->colors[i] = color.pixel; 258 } 259 260 /* init */ 261 wa.override_redirect = 1; 262 wa.background_pixel = lock->colors[INIT]; 263 lock->win = XCreateWindow(dpy, lock->root, 0, 0, 264 DisplayWidth(dpy, lock->screen), 265 DisplayHeight(dpy, lock->screen), 266 0, DefaultDepth(dpy, lock->screen), 267 CopyFromParent, 268 DefaultVisual(dpy, lock->screen), 269 CWOverrideRedirect | CWBackPixel, &wa); 270 if(lock->bgmap) 271 XSetWindowBackgroundPixmap(dpy, lock->win, lock->bgmap); 272 lock->pmap = XCreateBitmapFromData(dpy, lock->win, curs, 8, 8); 273 invisible = XCreatePixmapCursor(dpy, lock->pmap, lock->pmap, 274 &color, &color, 0, 0); 275 XDefineCursor(dpy, lock->win, invisible); 276 277 /* Try to grab mouse pointer *and* keyboard for 600ms, else fail the lock */ 278 for (i = 0, ptgrab = kbgrab = -1; i < 6; i++) { 279 if (ptgrab != GrabSuccess) { 280 ptgrab = XGrabPointer(dpy, lock->root, False, 281 ButtonPressMask | ButtonReleaseMask | 282 PointerMotionMask, GrabModeAsync, 283 GrabModeAsync, None, invisible, CurrentTime); 284 } 285 if (kbgrab != GrabSuccess) { 286 kbgrab = XGrabKeyboard(dpy, lock->root, True, 287 GrabModeAsync, GrabModeAsync, CurrentTime); 288 } 289 290 /* input is grabbed: we can lock the screen */ 291 if (ptgrab == GrabSuccess && kbgrab == GrabSuccess) { 292 XMapRaised(dpy, lock->win); 293 if (rr->active) 294 XRRSelectInput(dpy, lock->win, RRScreenChangeNotifyMask); 295 296 XSelectInput(dpy, lock->root, SubstructureNotifyMask); 297 return lock; 298 } 299 300 /* retry on AlreadyGrabbed but fail on other errors */ 301 if ((ptgrab != AlreadyGrabbed && ptgrab != GrabSuccess) || 302 (kbgrab != AlreadyGrabbed && kbgrab != GrabSuccess)) 303 break; 304 305 usleep(100000); 306 } 307 308 /* we couldn't grab all input: fail out */ 309 if (ptgrab != GrabSuccess) 310 fprintf(stderr, "slock: unable to grab mouse pointer for screen %d\n", 311 screen); 312 if (kbgrab != GrabSuccess) 313 fprintf(stderr, "slock: unable to grab keyboard for screen %d\n", 314 screen); 315 return NULL; 316 } 317 318 static void 319 usage(void) 320 { 321 die("usage: slock [-v] [cmd [arg ...]]\n"); 322 } 323 324 int 325 main(int argc, char **argv) { 326 struct xrandr rr; 327 struct lock **locks; 328 struct passwd *pwd; 329 struct group *grp; 330 uid_t duid; 331 gid_t dgid; 332 const char *hash; 333 Display *dpy; 334 int s, nlocks, nscreens; 335 336 ARGBEGIN { 337 case 'v': 338 fprintf(stderr, "slock-"VERSION"\n"); 339 return 0; 340 default: 341 usage(); 342 } ARGEND 343 344 /* validate drop-user and -group */ 345 errno = 0; 346 if (!(pwd = getpwnam(user))) 347 die("slock: getpwnam %s: %s\n", user, 348 errno ? strerror(errno) : "user entry not found"); 349 duid = pwd->pw_uid; 350 errno = 0; 351 if (!(grp = getgrnam(group))) 352 die("slock: getgrnam %s: %s\n", group, 353 errno ? strerror(errno) : "group entry not found"); 354 dgid = grp->gr_gid; 355 356 #ifdef __linux__ 357 dontkillme(); 358 #endif 359 360 hash = gethash(); 361 errno = 0; 362 if (!crypt("", hash)) 363 die("slock: crypt: %s\n", strerror(errno)); 364 365 if (!(dpy = XOpenDisplay(NULL))) 366 die("slock: cannot open display\n"); 367 368 /* drop privileges */ 369 if (setgroups(0, NULL) < 0) 370 die("slock: setgroups: %s\n", strerror(errno)); 371 if (setgid(dgid) < 0) 372 die("slock: setgid: %s\n", strerror(errno)); 373 if (setuid(duid) < 0) 374 die("slock: setuid: %s\n", strerror(errno)); 375 376 /*Create screenshot Image*/ 377 Screen *scr = ScreenOfDisplay(dpy, DefaultScreen(dpy)); 378 image = imlib_create_image(scr->width,scr->height); 379 imlib_context_set_image(image); 380 imlib_context_set_display(dpy); 381 imlib_context_set_visual(DefaultVisual(dpy,0)); 382 imlib_context_set_drawable(RootWindow(dpy,XScreenNumberOfScreen(scr))); 383 imlib_copy_drawable_to_image(0,0,0,scr->width,scr->height,0,0,1); 384 385 #ifdef BLUR 386 387 /*Blur function*/ 388 imlib_image_blur(blurRadius); 389 #endif // BLUR 390 391 #ifdef PIXELATION 392 /*Pixelation*/ 393 int width = scr->width; 394 int height = scr->height; 395 396 for(int y = 0; y < height; y += pixelSize) 397 { 398 for(int x = 0; x < width; x += pixelSize) 399 { 400 int red = 0; 401 int green = 0; 402 int blue = 0; 403 404 Imlib_Color pixel; 405 Imlib_Color* pp; 406 pp = &pixel; 407 for(int j = 0; j < pixelSize && j < height; j++) 408 { 409 for(int i = 0; i < pixelSize && i < width; i++) 410 { 411 imlib_image_query_pixel(x+i,y+j,pp); 412 red += pixel.red; 413 green += pixel.green; 414 blue += pixel.blue; 415 } 416 } 417 red /= (pixelSize*pixelSize); 418 green /= (pixelSize*pixelSize); 419 blue /= (pixelSize*pixelSize); 420 imlib_context_set_color(red,green,blue,pixel.alpha); 421 imlib_image_fill_rectangle(x,y,pixelSize,pixelSize); 422 red = 0; 423 green = 0; 424 blue = 0; 425 } 426 } 427 428 429 #endif 430 /* check for Xrandr support */ 431 rr.active = XRRQueryExtension(dpy, &rr.evbase, &rr.errbase); 432 433 /* get number of screens in display "dpy" and blank them */ 434 nscreens = ScreenCount(dpy); 435 if (!(locks = calloc(nscreens, sizeof(struct lock *)))) 436 die("slock: out of memory\n"); 437 for (nlocks = 0, s = 0; s < nscreens; s++) { 438 if ((locks[s] = lockscreen(dpy, &rr, s)) != NULL) 439 nlocks++; 440 else 441 break; 442 } 443 XSync(dpy, 0); 444 445 /* did we manage to lock everything? */ 446 if (nlocks != nscreens) 447 return 1; 448 449 /* run post-lock command */ 450 if (argc > 0) { 451 switch (fork()) { 452 case -1: 453 die("slock: fork failed: %s\n", strerror(errno)); 454 case 0: 455 if (close(ConnectionNumber(dpy)) < 0) 456 die("slock: close: %s\n", strerror(errno)); 457 execvp(argv[0], argv); 458 fprintf(stderr, "slock: execvp %s: %s\n", argv[0], strerror(errno)); 459 _exit(1); 460 } 461 } 462 463 /* everything is now blank. Wait for the correct password */ 464 readpw(dpy, &rr, locks, nscreens, hash); 465 466 return 0; 467 }