slock-1.5004075500000000000000000000000001431707052700113045ustar00rootwheelslock-1.5/LICENSE010064400000000000000000000023251431707052700123670ustar00rootwheelMIT/X Consortium License © 2015-2016 Markus Teich © 2014 Dimitris Papastamos © 2006-2014 Anselm R Garbe © 2014-2016 Laslo Hunhold Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions: The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software. THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. slock-1.5/Makefile010064400000000000000000000030551431707052700130230ustar00rootwheel# slock - simple screen locker # See LICENSE file for copyright and license details. include config.mk SRC = slock.c ${COMPATSRC} OBJ = ${SRC:.c=.o} all: options slock options: @echo slock build options: @echo "CFLAGS = ${CFLAGS}" @echo "LDFLAGS = ${LDFLAGS}" @echo "CC = ${CC}" .c.o: @echo CC $< @${CC} -c ${CFLAGS} $< ${OBJ}: config.h config.mk arg.h util.h config.h: @echo creating $@ from config.def.h @cp config.def.h $@ slock: ${OBJ} @echo CC -o $@ @${CC} -o $@ ${OBJ} ${LDFLAGS} clean: @echo cleaning @rm -f slock ${OBJ} slock-${VERSION}.tar.gz dist: clean @echo creating dist tarball @mkdir -p slock-${VERSION} @cp -R LICENSE Makefile README slock.1 config.mk \ ${SRC} config.def.h arg.h util.h slock-${VERSION} @tar -cf slock-${VERSION}.tar slock-${VERSION} @gzip slock-${VERSION}.tar @rm -rf slock-${VERSION} install: all @echo installing executable file to ${DESTDIR}${PREFIX}/bin @mkdir -p ${DESTDIR}${PREFIX}/bin @cp -f slock ${DESTDIR}${PREFIX}/bin @chmod 755 ${DESTDIR}${PREFIX}/bin/slock @chmod u+s ${DESTDIR}${PREFIX}/bin/slock @echo installing manual page to ${DESTDIR}${MANPREFIX}/man1 @mkdir -p ${DESTDIR}${MANPREFIX}/man1 @sed "s/VERSION/${VERSION}/g" ${DESTDIR}${MANPREFIX}/man1/slock.1 @chmod 644 ${DESTDIR}${MANPREFIX}/man1/slock.1 uninstall: @echo removing executable file from ${DESTDIR}${PREFIX}/bin @rm -f ${DESTDIR}${PREFIX}/bin/slock @echo removing manual page from ${DESTDIR}${MANPREFIX}/man1 @rm -f ${DESTDIR}${MANPREFIX}/man1/slock.1 .PHONY: all options clean dist install uninstall slock-1.5/README010064400000000000000000000010211431707052700122320ustar00rootwheelslock - simple screen locker ============================ simple screen locker utility for X. Requirements ------------ In order to build slock you need the Xlib header files. Installation ------------ Edit config.mk to match your local setup (slock is installed into the /usr/local namespace by default). Afterwards enter the following command to build and install slock (if necessary as root): make clean install Running slock ------------- Simply invoke the 'slock' command. To get out of it, enter your password. slock-1.5/slock.1010064400000000000000000000015621431707052700125610ustar00rootwheel.Dd 2016-08-23 .Dt SLOCK 1 .Sh NAME .Nm slock .Nd simple X screen locker .Sh SYNOPSIS .Nm .Op Fl v .Op Ar cmd Op Ar arg ... .Sh DESCRIPTION .Nm is a simple X screen locker. If provided, .Ar cmd Op Ar arg ... is executed after the screen has been locked. .Sh OPTIONS .Bl -tag -width Ds .It Fl v Print version information to stdout and exit. .El .Sh SECURITY CONSIDERATIONS To make sure a locked screen can not be bypassed by switching VTs or killing the X server with Ctrl+Alt+Backspace, it is recommended to disable both in .Xr xorg.conf 5 for maximum security: .Bd -literal -offset left Section "ServerFlags" Option "DontVTSwitch" "True" Option "DontZap" "True" EndSection .Ed .Sh EXAMPLES $ .Nm /usr/sbin/s2ram .Sh CUSTOMIZATION .Nm can be customized by creating a custom config.h from config.def.h and (re)compiling the source code. This keeps it fast, secure and simple. slock-1.5/config.mk010064400000000000000000000015071431707052700131610ustar00rootwheel# slock version VERSION = 1.5 # Customize below to fit your system # paths PREFIX = /usr/local MANPREFIX = ${PREFIX}/share/man X11INC = /usr/X11R6/include X11LIB = /usr/X11R6/lib # includes and libs INCS = -I. -I/usr/include -I${X11INC} LIBS = -L/usr/lib -lc -lcrypt -L${X11LIB} -lX11 -lXext -lXrandr # flags CPPFLAGS = -DVERSION=\"${VERSION}\" -D_DEFAULT_SOURCE -DHAVE_SHADOW_H CFLAGS = -std=c99 -pedantic -Wall -Os ${INCS} ${CPPFLAGS} LDFLAGS = -s ${LIBS} COMPATSRC = explicit_bzero.c # On OpenBSD and Darwin remove -lcrypt from LIBS #LIBS = -L/usr/lib -lc -L${X11LIB} -lX11 -lXext -lXrandr # On *BSD remove -DHAVE_SHADOW_H from CPPFLAGS # On NetBSD add -D_NETBSD_SOURCE to CPPFLAGS #CPPFLAGS = -DVERSION=\"${VERSION}\" -D_BSD_SOURCE -D_NETBSD_SOURCE # On OpenBSD set COMPATSRC to empty #COMPATSRC = # compiler and linker CC = cc slock-1.5/slock.c010064400000000000000000000227561431707052700126530ustar00rootwheel/* See LICENSE file for license details. */ #define _XOPEN_SOURCE 500 #if HAVE_SHADOW_H #include #endif #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "arg.h" #include "util.h" char *argv0; enum { INIT, INPUT, FAILED, NUMCOLS }; struct lock { int screen; Window root, win; Pixmap pmap; 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 #include 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)); } } #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 (!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 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__ */ } #endif /* HAVE_SHADOW_H */ return hash; } 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); 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) { case XK_Return: 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); failure = 1; } explicit_bzero(&passwd, sizeof(passwd)); len = 0; break; case XK_Escape: explicit_bzero(&passwd, sizeof(passwd)); len = 0; break; case XK_BackSpace: if (len) passwd[--len] = '\0'; break; default: 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->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); } /* 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; } slock-1.5/explicit_bzero.c010064400000000000000000000005131431707052700145450ustar00rootwheel/* $OpenBSD: explicit_bzero.c,v 1.3 2014/06/21 02:34:26 matthew Exp $ */ /* * Public domain. * Written by Matthew Dempsky. */ #include __attribute__((weak)) void __explicit_bzero_hook(void *buf, size_t len) { } void explicit_bzero(void *buf, size_t len) { memset(buf, 0, len); __explicit_bzero_hook(buf, len); } slock-1.5/config.def.h010064400000000000000000000006171431707052700135370ustar00rootwheel/* user and group to drop privileges to */ static const char *user = "nobody"; static const char *group = "nogroup"; static const char *colorname[NUMCOLS] = { [INIT] = "black", /* after initialization */ [INPUT] = "#005577", /* during input */ [FAILED] = "#CC3333", /* wrong password */ }; /* treat a cleared input like a wrong password (color) */ static const int failonclear = 1; slock-1.5/arg.h010064400000000000000000000024361431707052700123070ustar00rootwheel/* * Copy me if you can. * by 20h */ #ifndef ARG_H__ #define ARG_H__ extern char *argv0; /* use main(int argc, char *argv[]) */ #define ARGBEGIN for (argv0 = *argv, argv++, argc--;\ argv[0] && argv[0][0] == '-'\ && argv[0][1];\ argc--, argv++) {\ char argc_;\ char **argv_;\ int brk_;\ if (argv[0][1] == '-' && argv[0][2] == '\0') {\ argv++;\ argc--;\ break;\ }\ for (brk_ = 0, argv[0]++, argv_ = argv;\ argv[0][0] && !brk_;\ argv[0]++) {\ if (argv_ != argv)\ break;\ argc_ = argv[0][0];\ switch (argc_) /* Handles obsolete -NUM syntax */ #define ARGNUM case '0':\ case '1':\ case '2':\ case '3':\ case '4':\ case '5':\ case '6':\ case '7':\ case '8':\ case '9' #define ARGEND }\ } #define ARGC() argc_ #define ARGNUMF() (brk_ = 1, estrtonum(argv[0], 0, INT_MAX)) #define EARGF(x) ((argv[0][1] == '\0' && argv[1] == NULL)?\ ((x), abort(), (char *)0) :\ (brk_ = 1, (argv[0][1] != '\0')?\ (&argv[0][1]) :\ (argc--, argv++, argv[0]))) #define ARGF() ((argv[0][1] == '\0' && argv[1] == NULL)?\ (char *)0 :\ (brk_ = 1, (argv[0][1] != '\0')?\ (&argv[0][1]) :\ (argc--, argv++, argv[0]))) #define LNGARG() &argv[0][0] #endif slock-1.5/util.h010064400000000000000000000000731431707052700125060ustar00rootwheel#undef explicit_bzero void explicit_bzero(void *, size_t);