X-Git-Url: https://git.xinqibao.xyz/slock.git/blobdiff_plain/10ccc43597910428a22129cd942881835d95b5c0..a6dc051e3744ce5b14c54d2d246d3e8258207e76:/slock.c

diff --git a/slock.c b/slock.c
index 72afd1e..4531f95 100644
--- a/slock.c
+++ b/slock.c
@@ -1,129 +1,338 @@
-/* (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
-
 #if HAVE_SHADOW_H
 #include <shadow.h>
-#else
-#include <pwd.h>
 #endif
 
 #include <ctype.h>
+#include <errno.h>
+#include <pwd.h>
+#include <stdarg.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>
 
-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;
+#if HAVE_BSD_AUTH
+#include <login_cap.h>
+#include <bsd_auth.h>
 #endif
-	unsigned int len;
-	Bool running = True;
-	Cursor invisible;
-	Display *dpy;
-	KeySym ksym;
+
+enum {
+	INIT,
+	INPUT,
+	FAILED,
+	NUMCOLS
+};
+
+#include "config.h"
+
+typedef struct {
+	int screen;
+	Window root, win;
 	Pixmap pmap;
-	Window w;
-	XColor black, dummy;
-	XEvent ev;
-	XSetWindowAttributes wa;
+	unsigned long colors[NUMCOLS];
+} Lock;
+
+static Lock **locks;
+static int nscreens;
+static Bool running = True;
+static Bool failure = False;
+static Bool rr;
+static int rrevbase;
+static int rrerrbase;
+
+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>
+
+static void
+dontkillme(void)
+{
+	int fd;
 
-	if((argc > 1) && !strncmp(argv[1], "-v", 3)) {
-		fputs("slock-"VERSION", (C)opyright MMVI Anselm R. Garbe\n", stdout);
-		exit(EXIT_SUCCESS);
+	fd = open("/proc/self/oom_score_adj", O_WRONLY);
+	if (fd < 0 && errno == ENOENT) {
+		return;
 	}
-	if(geteuid() != 0) {
-		fputs("slock: cannot retrieve password entry (make sure to suid slock)\n", stderr);
-		exit(EXIT_FAILURE);
+	if (fd < 0 || write(fd, "-1000\n", (sizeof("-1000\n") - 1)) !=
+	    (sizeof("-1000\n") - 1) || close(fd) != 0) {
+		die("can't tame the oom-killer. is suid or sgid set?\n");
 	}
-#if HAVE_SHADOW_H
-	sp = getspnam(getenv("USER"));
-	endspent();
-#else
-	pw = getpwuid(getuid());
-	endpwent();
+}
 #endif
-	if(!(dpy = XOpenDisplay(0))) {
-		fputs("slock: cannot open display\n", stderr);
-		exit(EXIT_FAILURE);
+
+#ifndef HAVE_BSD_AUTH
+/* only run as root */
+static const char *
+getpw(void)
+{
+	const char *rval;
+	struct passwd *pw;
+
+	errno = 0;
+	if (!(pw = getpwuid(getuid()))) {
+		if (errno)
+			die("slock: getpwuid: %s\n", strerror(errno));
+		else
+			die("slock: cannot retrieve password entry\n");
 	}
-	screen = DefaultScreen(dpy);
+	rval = pw->pw_passwd;
 
-	/* init */
-	passwd[0] = 0;
+#if HAVE_SHADOW_H
+	if (rval[0] == 'x' && rval[1] == '\0') {
+		struct spwd *sp;
+		if (!(sp = getspnam(getenv("USER"))))
+			die("slock: cannot retrieve shadow entry (make sure to suid or sgid slock)\n");
+		rval = sp->sp_pwdp;
+	}
+#endif
 
-	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);
-	running = XGrabPointer(dpy, RootWindow(dpy, screen), False,
-			ButtonPressMask | ButtonReleaseMask | PointerMotionMask,
-			GrabModeAsync, GrabModeSync, None, invisible, CurrentTime) == GrabSuccess
-		&& XGrabKeyboard(dpy, RootWindow(dpy, screen), True, GrabModeAsync,
-			 GrabModeAsync, CurrentTime) == GrabSuccess;
-	XMapRaised(dpy, w);
-	XSync(dpy, False);
+	/* drop privileges */
+	if (geteuid() == 0 &&
+	    ((getegid() != pw->pw_gid && setgid(pw->pw_gid) < 0) || setuid(pw->pw_uid) < 0))
+		die("slock: cannot drop privileges\n");
+	return rval;
+}
+#endif
+
+static void
+#ifdef HAVE_BSD_AUTH
+readpw(Display *dpy)
+#else
+readpw(Display *dpy, const char *pws)
+#endif
+{
+	char buf[32], passwd[256];
+	int num, screen;
+	unsigned int len, color;
+	KeySym ksym;
+	XEvent ev;
+	static int oldc = INIT;
+
+	len = 0;
+	running = True;
 
-	/* main event loop */
-	while(running && !XNextEvent(dpy, &ev))
-		if(ev.type == KeyPress) {
-			len = strlen(passwd);
+	/* As "slock" stands for "Simple X display locker", the DPMS settings
+	 * had been removed and you can set it with "xset" or some other
+	 * utility. This way the user can easily set a customized DPMS
+	 * timeout. */
+	while (running && !XNextEvent(dpy, &ev)) {
+		if (ev.type == KeyPress) {
 			buf[0] = 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;
-			switch(ksym) {
+			switch (ksym) {
 			case XK_Return:
-#if HAVE_SHADOW_H
-				if((running = strncmp(crypt(passwd, sp->sp_pwdp), sp->sp_pwdp, sizeof(passwd))))
+				passwd[len] = 0;
+#ifdef HAVE_BSD_AUTH
+				running = !auth_userokay(getlogin(), NULL, "auth-xlock", passwd);
 #else
-				if((running = strncmp(crypt(passwd, pw->pw_passwd), pw->pw_passwd, sizeof(passwd))))
+				running = !!strcmp(crypt(passwd, pws), pws);
 #endif
+				if (running) {
 					XBell(dpy, 100);
-				passwd[0] = 0;
+					failure = True;
+				}
+				len = 0;
 				break;
 			case XK_Escape:
-				passwd[0] = 0;
+				len = 0;
 				break;
 			case XK_BackSpace:
-				if(len)
-					passwd[--len] = 0;
+				if (len)
+					--len;
 				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;
 			}
-		}
+			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 && ev.type == rrevbase + RRScreenChangeNotify) {
+			XRRScreenChangeNotifyEvent *rre = (XRRScreenChangeNotifyEvent*)&ev;
+			for (screen = 0; screen < nscreens; screen++) {
+				if (locks[screen]->win == rre->window) {
+					XResizeWindow(dpy, locks[screen]->win, rre->width, rre->height);
+					XClearWindow(dpy, locks[screen]->win);
+				}
+			}
+		} else for (screen = 0; screen < nscreens; screen++)
+			XRaiseWindow(dpy, locks[screen]->win);
+	}
+}
+
+static void
+unlockscreen(Display *dpy, Lock *lock)
+{
+	if(dpy == NULL || lock == NULL)
+		return;
+
 	XUngrabPointer(dpy, CurrentTime);
-	XFreePixmap(dpy, pmap);
-	XDestroyWindow(dpy, w);
+	XFreeColors(dpy, DefaultColormap(dpy, lock->screen), lock->colors, NUMCOLS, 0);
+	XFreePixmap(dpy, lock->pmap);
+	XDestroyWindow(dpy, lock->win);
+
+	free(lock);
+}
+
+static Lock *
+lockscreen(Display *dpy, int screen)
+{
+	char curs[] = {0, 0, 0, 0, 0, 0, 0, 0};
+	unsigned int len;
+	int i;
+	Lock *lock;
+	XColor color, dummy;
+	XSetWindowAttributes wa;
+	Cursor invisible;
+
+	if (!running || dpy == NULL || screen < 0 || !(lock = malloc(sizeof(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);
+	XMapRaised(dpy, lock->win);
+	if (rr)
+		XRRSelectInput(dpy, lock->win, RRScreenChangeNotifyMask);
+
+	/* Try to grab mouse pointer *and* keyboard, else fail the lock */
+	for (len = 1000; len; len--) {
+		if (XGrabPointer(dpy, lock->root, False, ButtonPressMask | ButtonReleaseMask | PointerMotionMask,
+		    GrabModeAsync, GrabModeAsync, None, invisible, CurrentTime) == GrabSuccess)
+			break;
+		usleep(1000);
+	}
+	if (!len) {
+		fprintf(stderr, "slock: unable to grab mouse pointer for screen %d\n", screen);
+	} else {
+		for (len = 1000; len; len--) {
+			if (XGrabKeyboard(dpy, lock->root, True, GrabModeAsync, GrabModeAsync, CurrentTime) == GrabSuccess) {
+				/* everything fine, we grabbed both inputs */
+				XSelectInput(dpy, lock->root, SubstructureNotifyMask);
+				return lock;
+			}
+			usleep(1000);
+		}
+		fprintf(stderr, "slock: unable to grab keyboard for screen %d\n", screen);
+	}
+	/* grabbing one of the inputs failed */
+	running = 0;
+	unlockscreen(dpy, lock);
+	return NULL;
+}
+
+int
+main(int argc, char **argv)
+{
+#ifndef HAVE_BSD_AUTH
+	const char *pws;
+#endif
+	Display *dpy;
+	int screen;
+
+#ifdef __linux__
+	dontkillme();
+#endif
+
+	if (!getpwuid(getuid()))
+		die("slock: no passwd entry for you\n");
+
+#ifndef HAVE_BSD_AUTH
+	pws = getpw();
+#endif
+
+	if (!(dpy = XOpenDisplay(0)))
+		die("slock: cannot open display\n");
+	rr = XRRQueryExtension(dpy, &rrevbase, &rrerrbase);
+	/* Get the number of screens in display "dpy" and blank them all. */
+	nscreens = ScreenCount(dpy);
+	if (!(locks = malloc(sizeof(Lock*) * nscreens)))
+		die("slock: malloc: %s\n", strerror(errno));
+	int nlocks = 0;
+	for (screen = 0; screen < nscreens; screen++) {
+		if ((locks[screen] = lockscreen(dpy, screen)) != NULL)
+			nlocks++;
+	}
+	XSync(dpy, False);
+
+	/* Did we actually manage to lock something? */
+	if (nlocks == 0) { /* nothing to protect */
+		free(locks);
+		XCloseDisplay(dpy);
+		return 1;
+	}
+
+	if (argc >= 2 && fork() == 0) {
+		if (dpy)
+			close(ConnectionNumber(dpy));
+		execvp(argv[1], argv+1);
+		die("slock: execvp %s failed: %s\n", argv[1], strerror(errno));
+	}
+
+	/* Everything is now blank. Now wait for the correct password. */
+#ifdef HAVE_BSD_AUTH
+	readpw(dpy);
+#else
+	readpw(dpy, pws);
+#endif
+
+	/* Password ok, unlock everything and quit. */
+	for (screen = 0; screen < nscreens; screen++)
+		unlockscreen(dpy, locks[screen]);
+
+	free(locks);
 	XCloseDisplay(dpy);
+
 	return 0;
 }