there can only be one window in the event

[slock.git] / slock.c

diff --git a/slock.c b/slock.c
index 0f4c3cc..700acfb 100644 (file)
--- a/slock.c
+++ b/slock.c
@@ -1,126 +1,393 @@
-/* (C)opyright MMIV-MMV Anselm R. Garbe <garbeam at gmail dot com>
- * See LICENSE file for license details.
- */
+/* See LICENSE file for license details. */

 #define _XOPEN_SOURCE 500
 #define _XOPEN_SOURCE 500

-

 #if HAVE_SHADOW_H
 #include <shadow.h>
 #if HAVE_SHADOW_H
 #include <shadow.h>

-#else
-#include <pwd.h>

 #endif
 
 #include <ctype.h>
 #endif
 
 #include <ctype.h>

+#include <errno.h>
+#include <grp.h>
+#include <pwd.h>
+#include <stdarg.h>

 #include <stdlib.h>
 #include <stdio.h>
 #include <string.h>
 #include <unistd.h>
 #include <sys/types.h>
 #include <stdlib.h>
 #include <stdio.h>
 #include <string.h>
 #include <unistd.h>
 #include <sys/types.h>

+#include <X11/extensions/Xrandr.h>

 #include <X11/keysym.h>
 #include <X11/Xlib.h>
 #include <X11/Xutil.h>
 
 #include <X11/keysym.h>
 #include <X11/Xlib.h>
 #include <X11/Xutil.h>
 

-int
-main(int argc, char **argv) {
-       char curs[] = {0, 0, 0, 0, 0, 0, 0, 0};
-       char buf[32], passwd[256];
-       int num, screen;
-#if HAVE_SHADOW_H
-       struct spwd *sp;
-#else
-       struct passwd *pw;
-#endif
-       unsigned int len;
-       Bool running = True;
-       Cursor invisible;
-       Display *dpy;
-       KeySym ksym;
+#include "arg.h"
+#include "util.h"
+
+char *argv0;
+
+enum {
+       INIT,
+       INPUT,
+       FAILED,
+       NUMCOLS
+};
+
+struct lock {
+       int screen;
+       Window root, win;

        Pixmap pmap;
        Pixmap pmap;

-       Window w;
-       XColor black, dummy;
-       XEvent ev;
-       XSetWindowAttributes wa;
+       unsigned long colors[NUMCOLS];
+};
+
+struct xrandr {
+       int active;
+       int evbase;
+       int errbase;
+};
+
+#include "config.h"
+
+static void
+die(const char *errstr, ...)
+{
+       va_list ap;
+
+       va_start(ap, errstr);
+       vfprintf(stderr, errstr, ap);
+       va_end(ap);
+       exit(1);
+}
+
+#ifdef __linux__
+#include <fcntl.h>
+#include <linux/oom.h>

 
 

-       if((argc > 1) && !strncmp(argv[1], "-v", 3)) {
-               fputs("slock-"VERSION", (C)opyright MMVI Anselm R. Garbe\n", stdout);
-               exit(EXIT_SUCCESS);
+static void
+dontkillme(void)
+{
+       FILE *f;
+       const char oomfile[] = "/proc/self/oom_score_adj";
+
+       if (!(f = fopen(oomfile, "w"))) {
+               if (errno == ENOENT)
+                       return;
+               die("slock: fopen %s: %s\n", oomfile, strerror(errno));
+       }
+       fprintf(f, "%d", OOM_SCORE_ADJ_MIN);
+       if (fclose(f)) {
+               if (errno == EACCES)
+                       die("slock: unable to disable OOM killer. "
+                           "Make sure to suid or sgid slock.\n");
+               else
+                       die("slock: fclose %s: %s\n", oomfile, strerror(errno));

        }
        }

-       if(geteuid() != 0) {
-               fputs("slock: cannot retrieve password entry (make sure to suid slock)\n", stderr);
-               exit(EXIT_FAILURE);
+}
+#endif
+
+static const char *
+gethash(void)
+{
+       const char *hash;
+       struct passwd *pw;
+
+       /* Check if the current user has a password entry */
+       errno = 0;
+       if (!(pw = getpwuid(getuid()))) {
+               if (errno)
+                       die("slock: getpwuid: %s\n", strerror(errno));
+               else
+                       die("slock: cannot retrieve password entry\n");

        }
        }

+       hash = pw->pw_passwd;
+

 #if HAVE_SHADOW_H
 #if HAVE_SHADOW_H

-       sp = getspnam(getenv("USER"));
-       endspent();
+       if (!strcmp(hash, "x")) {
+               struct spwd *sp;
+               if (!(sp = getspnam(pw->pw_name)))
+                       die("slock: getspnam: cannot retrieve shadow entry. "
+                           "Make sure to suid or sgid slock.\n");
+               hash = sp->sp_pwdp;
+       }

 #else
 #else

-       pw = getpwuid(getuid());
-       endpwent();
-#endif
-       if(!(dpy = XOpenDisplay(0))) {
-               fputs("slock: cannot open display\n", stderr);
-               exit(EXIT_FAILURE);
+       if (!strcmp(hash, "*")) {
+#ifdef __OpenBSD__
+               if (!(pw = getpwuid_shadow(getuid())))
+                       die("slock: getpwnam_shadow: cannot retrieve shadow entry. "
+                           "Make sure to suid or sgid slock.\n");
+               hash = pw->pw_passwd;
+#else
+               die("slock: getpwuid: cannot retrieve shadow entry. "
+                   "Make sure to suid or sgid slock.\n");
+#endif /* __OpenBSD__ */

        }
        }

-       screen = DefaultScreen(dpy);
+#endif /* HAVE_SHADOW_H */

 
 

-       /* init */
-       passwd[0] = 0;
-       while(XGrabKeyboard(dpy, RootWindow(dpy, screen), True, GrabModeAsync,
-                        GrabModeAsync, CurrentTime) != GrabSuccess)
-               usleep(1000);
+       return hash;
+}

 
 

-       wa.override_redirect = 1;
-       wa.background_pixel = BlackPixel(dpy, screen);
-       w = XCreateWindow(dpy, RootWindow(dpy, screen), 0, 0,
-                       DisplayWidth(dpy, screen), DisplayHeight(dpy, screen),
-                       0, DefaultDepth(dpy, screen), CopyFromParent,
-                       DefaultVisual(dpy, screen), CWOverrideRedirect | CWBackPixel, &wa);
-
-       XAllocNamedColor(dpy, DefaultColormap(dpy, screen), "black", &black, &dummy);
-       pmap = XCreateBitmapFromData(dpy, w, curs, 8, 8);
-       invisible = XCreatePixmapCursor(dpy, pmap, pmap, &black, &black, 0, 0);
-       XDefineCursor(dpy, w, invisible);
-       XMapRaised(dpy, w);
-       XSync(dpy, False);
-
-       /* main event loop */
-       while(running && !XNextEvent(dpy, &ev))
-               if(ev.type == KeyPress) {
-                       len = strlen(passwd);
-                       buf[0] = 0;
+static void
+readpw(Display *dpy, struct xrandr *rr, struct lock **locks, int nscreens,
+       const char *hash)
+{
+       XRRScreenChangeNotifyEvent *rre;
+       char buf[32], passwd[256], *inputhash;
+       int num, screen, running, failure, oldc;
+       unsigned int len, color;
+       KeySym ksym;
+       XEvent ev;
+
+       len = 0;
+       running = 1;
+       failure = 0;
+       oldc = INIT;
+
+       while (running && !XNextEvent(dpy, &ev)) {
+               if (ev.type == KeyPress) {
+                       explicit_bzero(&buf, sizeof(buf));

                        num = XLookupString(&ev.xkey, buf, sizeof(buf), &ksym, 0);
                        num = XLookupString(&ev.xkey, buf, sizeof(buf), &ksym, 0);

-                       if(IsFunctionKey(ksym) || IsKeypadKey(ksym)
-                                       || IsMiscFunctionKey(ksym) || IsPFKey(ksym)
-                                       || IsPrivateKeypadKey(ksym))
+                       if (IsKeypadKey(ksym)) {
+                               if (ksym == XK_KP_Enter)
+                                       ksym = XK_Return;
+                               else if (ksym >= XK_KP_0 && ksym <= XK_KP_9)
+                                       ksym = (ksym - XK_KP_0) + XK_0;
+                       }
+                       if (IsFunctionKey(ksym) ||
+                           IsKeypadKey(ksym) ||
+                           IsMiscFunctionKey(ksym) ||
+                           IsPFKey(ksym) ||
+                           IsPrivateKeypadKey(ksym))

                                continue;
                                continue;

-                       switch(ksym) {
+                       switch (ksym) {

                        case XK_Return:
                        case XK_Return:

-#if HAVE_SHADOW_H
-                               if((running = strncmp(crypt(passwd, sp->sp_pwdp), sp->sp_pwdp, sizeof(passwd))))
-#else
-                               if((running = strncmp(crypt(passwd, pw->pw_passwd), pw->pw_passwd, sizeof(passwd))))
-#endif
+                               passwd[len] = '\0';
+                               errno = 0;
+                               if (!(inputhash = crypt(passwd, hash)))
+                                       fprintf(stderr, "slock: crypt: %s\n", strerror(errno));
+                               else
+                                       running = !!strcmp(inputhash, hash);
+                               if (running) {

                                        XBell(dpy, 100);
                                        XBell(dpy, 100);

-                               passwd[0] = 0;
+                                       failure = 1;
+                               }
+                               explicit_bzero(&passwd, sizeof(passwd));
+                               len = 0;

                                break;
                        case XK_Escape:
                                break;
                        case XK_Escape:

-                               passwd[0] = 0;
+                               explicit_bzero(&passwd, sizeof(passwd));
+                               len = 0;

                                break;
                        case XK_BackSpace:
                                break;
                        case XK_BackSpace:

-                               if(len)
-                                       passwd[--len] = 0;
+                               if (len)
+                                       passwd[len--] = '\0';

                                break;
                        default:
                                break;
                        default:

-                               if(num && !iscntrl((int) buf[0])) {
-                                       buf[num] = 0;
-                                       if(len)
-                                               strncat(passwd, buf, sizeof(passwd));
-                                       else
-                                               strncpy(passwd, buf, sizeof(passwd));
+                               if (num && !iscntrl((int)buf[0]) &&
+                                   (len + num < sizeof(passwd))) {
+                                       memcpy(passwd + len, buf, num);
+                                       len += num;

                                }
                                break;
                        }
                                }
                                break;
                        }

+                       color = len ? INPUT : ((failure || failonclear) ? FAILED : INIT);
+                       if (running && oldc != color) {
+                               for (screen = 0; screen < nscreens; screen++) {
+                                       XSetWindowBackground(dpy,
+                                                            locks[screen]->win,
+                                                            locks[screen]->colors[color]);
+                                       XClearWindow(dpy, locks[screen]->win);
+                               }
+                               oldc = color;
+                       }
+               } else if (rr->active && ev.type == rr->evbase + RRScreenChangeNotify) {
+                       rre = (XRRScreenChangeNotifyEvent*)&ev;
+                       for (screen = 0; screen < nscreens; screen++) {
+                               if (locks[screen]->win == rre->window) {
+                                       if (rre->rotation == RR_Rotate_90 ||
+                                           rre->rotation == RR_Rotate_270)
+                                               XResizeWindow(dpy, locks[screen]->win,
+                                                             rre->height, rre->width);
+                                       else
+                                               XResizeWindow(dpy, locks[screen]->win,
+                                                             rre->width, rre->height);
+                                       XClearWindow(dpy, locks[screen]->win);
+                                       break;
+                               }
+                       }
+               } else for (screen = 0; screen < nscreens; screen++)
+                       XRaiseWindow(dpy, locks[screen]->win);
+       }
+}
+
+static struct lock *
+lockscreen(Display *dpy, struct xrandr *rr, int screen)
+{
+       char curs[] = {0, 0, 0, 0, 0, 0, 0, 0};
+       int i, ptgrab, kbgrab;
+       struct lock *lock;
+       XColor color, dummy;
+       XSetWindowAttributes wa;
+       Cursor invisible;
+
+       if (dpy == NULL || screen < 0 || !(lock = malloc(sizeof(struct lock))))
+               return NULL;
+
+       lock->screen = screen;
+       lock->root = RootWindow(dpy, lock->screen);
+
+       for (i = 0; i < NUMCOLS; i++) {
+               XAllocNamedColor(dpy, DefaultColormap(dpy, lock->screen),
+                                colorname[i], &color, &dummy);
+               lock->colors[i] = color.pixel;
+       }
+
+       /* init */
+       wa.override_redirect = 1;
+       wa.background_pixel = lock->colors[INIT];
+       lock->win = XCreateWindow(dpy, lock->root, 0, 0,
+                                 DisplayWidth(dpy, lock->screen),
+                                 DisplayHeight(dpy, lock->screen),
+                                 0, DefaultDepth(dpy, lock->screen),
+                                 CopyFromParent,
+                                 DefaultVisual(dpy, lock->screen),
+                                 CWOverrideRedirect | CWBackPixel, &wa);
+       lock->pmap = XCreateBitmapFromData(dpy, lock->win, curs, 8, 8);
+       invisible = XCreatePixmapCursor(dpy, lock->pmap, lock->pmap,
+                                       &color, &color, 0, 0);
+       XDefineCursor(dpy, lock->win, invisible);
+
+       /* Try to grab mouse pointer *and* keyboard for 600ms, else fail the lock */
+       for (i = 0, ptgrab = kbgrab = -1; i < 6; i++) {
+               if (ptgrab != GrabSuccess) {
+                       ptgrab = XGrabPointer(dpy, lock->root, False,
+                                             ButtonPressMask | ButtonReleaseMask |
+                                             PointerMotionMask, GrabModeAsync,
+                                             GrabModeAsync, None, invisible, CurrentTime);
+               }
+               if (kbgrab != GrabSuccess) {
+                       kbgrab = XGrabKeyboard(dpy, lock->root, True,
+                                              GrabModeAsync, GrabModeAsync, CurrentTime);

                }
                }

-       XFreePixmap(dpy, pmap);
-       XDestroyWindow(dpy, w);
-       XCloseDisplay(dpy);
+
+               /* input is grabbed: we can lock the screen */
+               if (ptgrab == GrabSuccess && kbgrab == GrabSuccess) {
+                       XMapRaised(dpy, lock->win);
+                       if (rr->active)
+                               XRRSelectInput(dpy, lock->win, RRScreenChangeNotifyMask);
+
+                       XSelectInput(dpy, lock->root, SubstructureNotifyMask);
+                       return lock;
+               }
+
+               /* retry on AlreadyGrabbed but fail on other errors */
+               if ((ptgrab != AlreadyGrabbed && ptgrab != GrabSuccess) ||
+                   (kbgrab != AlreadyGrabbed && kbgrab != GrabSuccess))
+                       break;
+
+               usleep(100000);
+       }
+
+       /* we couldn't grab all input: fail out */
+       if (ptgrab != GrabSuccess)
+               fprintf(stderr, "slock: unable to grab mouse pointer for screen %d\n",
+                       screen);
+       if (kbgrab != GrabSuccess)
+               fprintf(stderr, "slock: unable to grab keyboard for screen %d\n",
+                       screen);
+       return NULL;
+}
+
+static void
+usage(void)
+{
+       die("usage: slock [-v] [cmd [arg ...]]\n");
+}
+
+int
+main(int argc, char **argv) {
+       struct xrandr rr;
+       struct lock **locks;
+       struct passwd *pwd;
+       struct group *grp;
+       uid_t duid;
+       gid_t dgid;
+       const char *hash;
+       Display *dpy;
+       int s, nlocks, nscreens;
+
+       ARGBEGIN {
+       case 'v':
+               fprintf(stderr, "slock-"VERSION"\n");
+               return 0;
+       default:
+               usage();
+       } ARGEND
+
+       /* validate drop-user and -group */
+       errno = 0;
+       if (!(pwd = getpwnam(user)))
+               die("slock: getpwnam %s: %s\n", user,
+                   errno ? strerror(errno) : "user entry not found");
+       duid = pwd->pw_uid;
+       errno = 0;
+       if (!(grp = getgrnam(group)))
+               die("slock: getgrnam %s: %s\n", group,
+                   errno ? strerror(errno) : "group entry not found");
+       dgid = grp->gr_gid;
+
+#ifdef __linux__
+       dontkillme();
+#endif
+
+       hash = gethash();
+       errno = 0;
+       if (!crypt("", hash))
+               die("slock: crypt: %s\n", strerror(errno));
+
+       if (!(dpy = XOpenDisplay(NULL)))
+               die("slock: cannot open display\n");
+
+       /* drop privileges */
+       if (setgroups(0, NULL) < 0)
+               die("slock: setgroups: %s\n", strerror(errno));
+       if (setgid(dgid) < 0)
+               die("slock: setgid: %s\n", strerror(errno));
+       if (setuid(duid) < 0)
+               die("slock: setuid: %s\n", strerror(errno));
+
+       /* check for Xrandr support */
+       rr.active = XRRQueryExtension(dpy, &rr.evbase, &rr.errbase);
+
+       /* get number of screens in display "dpy" and blank them */
+       nscreens = ScreenCount(dpy);
+       if (!(locks = calloc(nscreens, sizeof(struct lock *))))
+               die("slock: out of memory\n");
+       for (nlocks = 0, s = 0; s < nscreens; s++) {
+               if ((locks[s] = lockscreen(dpy, &rr, s)) != NULL)
+                       nlocks++;
+               else
+                       break;
+       }
+       XSync(dpy, 0);
+
+       /* did we manage to lock everything? */
+       if (nlocks != nscreens)
+               return 1;
+
+       /* run post-lock command */
+       if (argc > 0) {
+               switch (fork()) {
+               case -1:
+                       die("slock: fork failed: %s\n", strerror(errno));
+               case 0:
+                       if (close(ConnectionNumber(dpy)) < 0)
+                               die("slock: close: %s\n", strerror(errno));
+                       execvp(argv[0], argv);
+                       fprintf(stderr, "slock: execvp %s: %s\n", argv[0], strerror(errno));
+                       _exit(1);
+               }
+       }
+
+       /* everything is now blank. Wait for the correct password */
+       readpw(dpy, &rr, locks, nscreens, hash);
+

        return 0;
 }
        return 0;
 }