removed Sander from -v by request
[slock.git] / slock.c
1 /* © 2006-2007 Anselm R. Garbe <garbeam at gmail dot com>
2  * See LICENSE file for license details. */
3 #define _XOPEN_SOURCE 500
4 #if HAVE_SHADOW_H
5 #include <shadow.h>
6 #endif
7
8 #include <ctype.h>
9 #include <pwd.h>
10 #include <stdarg.h>
11 #include <stdlib.h>
12 #include <stdio.h>
13 #include <string.h>
14 #include <unistd.h>
15 #include <sys/types.h>
16 #include <X11/keysym.h>
17 #include <X11/Xlib.h>
18 #include <X11/Xutil.h>
19
20 void
21 eprint(const char *errstr, ...) {
22         va_list ap;
23
24         va_start(ap, errstr);
25         vfprintf(stderr, errstr, ap);
26         va_end(ap);
27         exit(EXIT_FAILURE);
28 }
29
30 const char *
31 get_password() { /* only run as root */
32         const char *rval;
33         struct passwd *pw;
34
35         if(geteuid() != 0)
36                 eprint("slock: cannot retrieve password entry (make sure to suid slock)\n");
37         pw = getpwuid(getuid());
38         endpwent();
39         rval =  pw->pw_passwd;
40
41 #if HAVE_SHADOW_H
42         {
43                 struct spwd *sp;
44                 sp = getspnam(getenv("USER"));
45                 endspent();
46                 rval = sp->sp_pwdp;
47         }
48 #endif
49         /* drop privileges */
50         if(setgid(pw->pw_gid) < 0 || setuid(pw->pw_uid) < 0)
51                 eprint("slock: cannot drop privileges\n");
52         return rval;
53 }
54
55 int
56 main(int argc, char **argv) {
57         char curs[] = {0, 0, 0, 0, 0, 0, 0, 0};
58         char buf[32], passwd[256];
59         int num, screen;
60         const char *pws;
61         unsigned int len;
62         Bool running = True;
63         Cursor invisible;
64         Display *dpy;
65         KeySym ksym;
66         Pixmap pmap;
67         Window root, w;
68         XColor black, dummy;
69         XEvent ev;
70         XSetWindowAttributes wa;
71
72         if((argc == 2) && !strcmp("-v", argv[1]))
73                 eprint("slock-"VERSION", © 2006-2007 Anselm R. Garbe\n");
74         else if(argc != 1)
75                 eprint("usage: slock [-v]\n");
76         pws = get_password();
77         if(!(dpy = XOpenDisplay(0)))
78                 eprint("slock: cannot open display\n");
79         screen = DefaultScreen(dpy);
80         root = RootWindow(dpy, screen);
81
82         /* init */
83         wa.override_redirect = 1;
84         wa.background_pixel = BlackPixel(dpy, screen);
85         w = XCreateWindow(dpy, root, 0, 0, DisplayWidth(dpy, screen), DisplayHeight(dpy, screen),
86                         0, DefaultDepth(dpy, screen), CopyFromParent,
87                         DefaultVisual(dpy, screen), CWOverrideRedirect | CWBackPixel, &wa);
88         XAllocNamedColor(dpy, DefaultColormap(dpy, screen), "black", &black, &dummy);
89         pmap = XCreateBitmapFromData(dpy, w, curs, 8, 8);
90         invisible = XCreatePixmapCursor(dpy, pmap, pmap, &black, &black, 0, 0);
91         XDefineCursor(dpy, w, invisible);
92         XMapRaised(dpy, w);
93         for(len = 1000; len; len--) {
94                 if(XGrabPointer(dpy, root, False, ButtonPressMask | ButtonReleaseMask | PointerMotionMask,
95                         GrabModeAsync, GrabModeAsync, None, invisible, CurrentTime) == GrabSuccess)
96                         break;
97                 usleep(1000);
98         }
99         if((running = running && (len > 0))) {
100                 for(len = 1000; len; len--) {
101                         if(XGrabKeyboard(dpy, root, True, GrabModeAsync, GrabModeAsync, CurrentTime)
102                                 == GrabSuccess)
103                                 break;
104                         usleep(1000);
105                 }
106                 running = (len > 0);
107         }
108         len = 0;
109         XSync(dpy, False);
110
111         /* main event loop */
112         while(running && !XNextEvent(dpy, &ev))
113                 if(ev.type == KeyPress) {
114                         buf[0] = 0;
115                         num = XLookupString(&ev.xkey, buf, sizeof buf, &ksym, 0);
116                         if(IsFunctionKey(ksym) || IsKeypadKey(ksym)
117                                         || IsMiscFunctionKey(ksym) || IsPFKey(ksym)
118                                         || IsPrivateKeypadKey(ksym))
119                                 continue;
120                         switch(ksym) {
121                         case XK_Return:
122                                 passwd[len] = 0;
123                                 if((running = strcmp(crypt(passwd, pws), pws)) != 0)
124                                         XBell(dpy, 100);
125                                 len = 0;
126                                 break;
127                         case XK_Escape:
128                                 len = 0;
129                                 break;
130                         case XK_BackSpace:
131                                 if(len)
132                                         --len;
133                                 break;
134                         default:
135                                 if(num && !iscntrl((int) buf[0]) && (len + num < sizeof passwd)) { 
136                                         memcpy(passwd + len, buf, num);
137                                         len += num;
138                                 }
139                                 break;
140                         }
141                 }
142         XUngrabPointer(dpy, CurrentTime);
143         XFreePixmap(dpy, pmap);
144         XDestroyWindow(dpy, w);
145         XCloseDisplay(dpy);
146         return 0;
147 }