X-Git-Url: https://git.danieliu.xyz/?a=blobdiff_plain;f=slock.c;h=d2f08862453615c3131332273fbd1d0187f4195c;hb=7d31ff65a0b0388f788ca6932c815ab29e5fb10f;hp=83d426aaccb9a469dd79587a6b3a9d889903db58;hpb=03a87179919eebab7d38c548e3ff8e2911512468;p=slock.git diff --git a/slock.c b/slock.c index 83d426a..d2f0886 100644 --- a/slock.c +++ b/slock.c @@ -6,6 +6,7 @@ #include #include +#include #include #include #include @@ -18,11 +19,6 @@ #include #include -#if HAVE_BSD_AUTH -#include -#include -#endif - #include "arg.h" #include "util.h" @@ -35,20 +31,20 @@ enum { NUMCOLS }; -#include "config.h" - -typedef struct { +struct lock { int screen; Window root, win; Pixmap pmap; unsigned long colors[NUMCOLS]; -} Lock; +}; -static Lock **locks; -static int nscreens; -static Bool rr; -static int rrevbase; -static int rrerrbase; +struct xrandr { + int active; + int evbase; + int errbase; +}; + +#include "config.h" static void die(const char *errstr, ...) @@ -80,70 +76,70 @@ dontkillme(void) if (fclose(f)) { if (errno == EACCES) die("slock: unable to disable OOM killer. " - "suid or sgid set?\n"); + "Make sure to suid or sgid slock.\n"); else - die("slock: fclose %s: %s\n", oomfile, - strerror(errno)); + die("slock: fclose %s: %s\n", oomfile, strerror(errno)); } } #endif -#ifndef HAVE_BSD_AUTH -/* only run as root */ static const char * -getpw(void) +gethash(void) { - const char *rval; + const char *hash; struct passwd *pw; + /* Check if the current user has a password entry */ errno = 0; if (!(pw = getpwuid(getuid()))) { if (errno) - die("getpwuid: %s\n", strerror(errno)); + die("slock: getpwuid: %s\n", strerror(errno)); else - die("cannot retrieve password entry\n"); + die("slock: cannot retrieve password entry\n"); } - rval = pw->pw_passwd; + hash = pw->pw_passwd; #if HAVE_SHADOW_H - if (rval[0] == 'x' && rval[1] == '\0') { + if (!strcmp(hash, "x")) { struct spwd *sp; - if (!(sp = getspnam(getenv("USER")))) - die("cannot retrieve shadow entry (make sure to suid or sgid slock)\n"); - rval = sp->sp_pwdp; + 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; } -#endif +#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 */ - /* drop privileges */ - if (geteuid() == 0 && - ((getegid() != pw->pw_gid && setgid(pw->pw_gid) < 0) || setuid(pw->pw_uid) < 0)) - die("cannot drop privileges\n"); - return rval; + return hash; } -#endif static void -#ifdef HAVE_BSD_AUTH -readpw(Display *dpy) -#else -readpw(Display *dpy, const char *pws) -#endif +readpw(Display *dpy, struct xrandr *rr, struct lock **locks, int nscreens, + const char *hash) { - char buf[32], passwd[256], *encrypted; - int num, screen, running, failure; + XRRScreenChangeNotifyEvent *rre; + char buf[32], passwd[256], *inputhash; + int num, screen, running, failure, oldc; unsigned int len, color; KeySym ksym; XEvent ev; - static int oldc = INIT; len = 0; running = 1; failure = 0; + oldc = INIT; - /* 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) { explicit_bzero(&buf, sizeof(buf)); @@ -162,19 +158,15 @@ readpw(Display *dpy, const char *pws) continue; switch (ksym) { case XK_Return: - passwd[len] = 0; -#ifdef HAVE_BSD_AUTH - running = !auth_userokay(getlogin(), NULL, "auth-slock", passwd); -#else + passwd[len] = '\0'; errno = 0; - if (!(encrypted = crypt(passwd, pws))) + if (!(inputhash = crypt(passwd, hash))) fprintf(stderr, "slock: crypt: %s\n", strerror(errno)); else - running = !!strcmp(encrypted, pws); -#endif + running = !!strcmp(inputhash, hash); if (running) { XBell(dpy, 100); - failure = True; + failure = 1; } explicit_bzero(&passwd, sizeof(passwd)); len = 0; @@ -185,28 +177,32 @@ readpw(Display *dpy, const char *pws) break; case XK_BackSpace: if (len) - passwd[len--] = 0; + passwd[len--] = '\0'; break; default: - if (num && !iscntrl((int)buf[0]) && (len + num < 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); + 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]); + 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; + } else if (rr->active && ev.type == rr->evbase + RRScreenChangeNotify) { + rre = (XRRScreenChangeNotifyEvent*)&ev; for (screen = 0; screen < nscreens; screen++) { if (locks[screen]->win == rre->window) { - XResizeWindow(dpy, locks[screen]->win, rre->width, rre->height); + XResizeWindow(dpy, locks[screen]->win, + rre->width, rre->height); XClearWindow(dpy, locks[screen]->win); } } @@ -215,81 +211,60 @@ readpw(Display *dpy, const char *pws) } } -static void -unlockscreen(Display *dpy, Lock *lock) -{ - if(dpy == NULL || lock == NULL) - return; - - XUngrabPointer(dpy, CurrentTime); - XUngrabKeyboard(dpy, CurrentTime); - XFreeColors(dpy, DefaultColormap(dpy, lock->screen), lock->colors, NUMCOLS, 0); - XFreePixmap(dpy, lock->pmap); - XDestroyWindow(dpy, lock->win); - - free(lock); -} - -static void -cleanup(Display *dpy) -{ - int s; - - for (s = 0; s < nscreens; ++s) - unlockscreen(dpy, locks[s]); - - free(locks); - XCloseDisplay(dpy); -} - -static Lock * -lockscreen(Display *dpy, int screen) +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; - Lock *lock; + struct lock *lock; XColor color, dummy; XSetWindowAttributes wa; Cursor invisible; - if (dpy == NULL || screen < 0 || !(lock = malloc(sizeof(Lock)))) + 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); + 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->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); + 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 = 6, ptgrab = kbgrab = -1; i; --i) { + 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); + ButtonPressMask | ButtonReleaseMask | + PointerMotionMask, GrabModeAsync, + GrabModeAsync, None, invisible, CurrentTime); } if (kbgrab != GrabSuccess) { kbgrab = XGrabKeyboard(dpy, lock->root, True, - GrabModeAsync, GrabModeAsync, CurrentTime); + GrabModeAsync, GrabModeAsync, CurrentTime); } /* input is grabbed: we can lock the screen */ if (ptgrab == GrabSuccess && kbgrab == GrabSuccess) { XMapRaised(dpy, lock->win); - if (rr) + if (rr->active) XRRSelectInput(dpy, lock->win, RRScreenChangeNotifyMask); XSelectInput(dpy, lock->root, SubstructureNotifyMask); @@ -306,9 +281,11 @@ lockscreen(Display *dpy, int screen) /* we couldn't grab all input: fail out */ if (ptgrab != GrabSuccess) - fprintf(stderr, "slock: unable to grab mouse pointer for screen %d\n", screen); + 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); + fprintf(stderr, "slock: unable to grab keyboard for screen %d\n", + screen); return NULL; } @@ -320,11 +297,15 @@ usage(void) int main(int argc, char **argv) { -#ifndef HAVE_BSD_AUTH - const char *pws; -#endif + 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; + int s, nlocks, nscreens; ARGBEGIN { case 'v': @@ -334,39 +315,47 @@ main(int argc, char **argv) { 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 - /* Check if the current user has a password entry */ + hash = gethash(); errno = 0; - if (!getpwuid(getuid())) { - if (errno == 0) - die("slock: no password entry for current user\n"); - else - die("slock: getpwuid: %s\n", strerror(errno)); - } - -#ifndef HAVE_BSD_AUTH - pws = getpw(); - if (strlen(pws) < 2) - die("slock: failed to get user password hash.\n"); -#endif + 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 = XRRQueryExtension(dpy, &rrevbase, &rrerrbase); + 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(Lock *)))) { - XCloseDisplay(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, s)) != NULL) + if ((locks[s] = lockscreen(dpy, &rr, s)) != NULL) nlocks++; else break; @@ -374,36 +363,25 @@ main(int argc, char **argv) { XSync(dpy, 0); /* did we manage to lock everything? */ - if (nlocks != nscreens) { - cleanup(dpy); + if (nlocks != nscreens) return 1; - } /* run post-lock command */ if (argc > 0) { switch (fork()) { case -1: - cleanup(dpy); 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)); + fprintf(stderr, "slock: execvp %s: %s\n", argv[0], strerror(errno)); _exit(1); } } /* everything is now blank. Wait for the correct password */ -#ifdef HAVE_BSD_AUTH - readpw(dpy); -#else - readpw(dpy, pws); -#endif - - /* password ok, unlock everything and quit */ - cleanup(dpy); + readpw(dpy, &rr, locks, nscreens, hash); return 0; }