clear passwords with explicit_bzero

[slock.git] / slock.c

diff --git a/slock.c b/slock.c
index a0ffed07e0cd321c2a5fcceda98fe9d10ca6f3d0..a00fbb9a8f37bbca4d40b04ed40cba525d183781 100644 (file)
--- a/slock.c
+++ b/slock.c
@@ -23,6 +23,8 @@
 #include <bsd_auth.h>
 #endif
 
+#include "util.h"
+
 enum {
        INIT,
        INPUT,
@@ -46,15 +48,14 @@ static Bool failure = False;
 static Bool rr;
 static int rrevbase;
 static int rrerrbase;
-static char *argv0;
 
 static void
 die(const char *errstr, ...)
 {
        va_list ap;
 
+       fputs("slock: ", stderr);
        va_start(ap, errstr);
-       fprintf(stderr, "%s: ", argv0);
        vfprintf(stderr, errstr, ap);
        va_end(ap);
        exit(1);
@@ -136,7 +137,7 @@ readpw(Display *dpy, const char *pws)
         * timeout. */
        while (running && !XNextEvent(dpy, &ev)) {
                if (ev.type == KeyPress) {
-                       buf[0] = 0;
+                       explicit_bzero(&buf, sizeof(buf));
                        num = XLookupString(&ev.xkey, buf, sizeof(buf), &ksym, 0);
                        if (IsKeypadKey(ksym)) {
                                if (ksym == XK_KP_Enter)
@@ -162,14 +163,16 @@ readpw(Display *dpy, const char *pws)
                                        XBell(dpy, 100);
                                        failure = True;
                                }
+                               explicit_bzero(&passwd, sizeof(passwd));
                                len = 0;
                                break;
                        case XK_Escape:
+                               explicit_bzero(&passwd, sizeof(passwd));
                                len = 0;
                                break;
                        case XK_BackSpace:
                                if (len)
-                                       --len;
+                                       passwd[len--] = 0;
                                break;
                        default:
                                if (num && !iscntrl((int)buf[0]) && (len + num < sizeof(passwd))) {
@@ -256,7 +259,7 @@ lockscreen(Display *dpy, int screen)
                usleep(1000);
        }
        if (!len) {
-               fprintf(stderr, "unable to grab mouse pointer for screen %d\n", screen);
+               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) {
@@ -266,7 +269,7 @@ lockscreen(Display *dpy, int screen)
                        }
                        usleep(1000);
                }
-               fprintf(stderr, "unable to grab keyboard for screen %d\n", screen);
+               fprintf(stderr, "slock: unable to grab keyboard for screen %d\n", screen);
        }
        /* grabbing one of the inputs failed */
        running = 0;
@@ -274,16 +277,27 @@ lockscreen(Display *dpy, int screen)
        return NULL;
 }
 
-int
-main(int argc, char **argv)
+static void
+usage(void)
 {
+       fprintf(stderr, "usage: slock [-v|POST_LOCK_CMD]\n");
+       exit(1);
+}
+
+int
+main(int argc, char **argv) {
 #ifndef HAVE_BSD_AUTH
        const char *pws;
 #endif
        Display *dpy;
        int screen;
 
-       argv0 = argv[0], argc--, argv++;
+       if ((argc >= 2) && !strcmp("-v", argv[1]))
+               die("version %s, © 2006-2016 slock engineers\n", VERSION);
+
+       /* treat first argument starting with a '-' as option */
+       if ((argc >= 2) && argv[1][0] == '-')
+               usage();
 
 #ifdef __linux__
        dontkillme();
@@ -317,11 +331,11 @@ main(int argc, char **argv)
                return 1;
        }
 
-       if (argc >= 1 && fork() == 0) {
+       if (argc >= 2 && fork() == 0) {
                if (dpy)
                        close(ConnectionNumber(dpy));
-               execvp(argv[0], argv);
-               die("execvp %s failed: %s\n", argv[0], strerror(errno));
+               execvp(argv[1], argv+1);
+               die("execvp %s failed: %s\n", argv[1], strerror(errno));
        }
 
        /* Everything is now blank. Now wait for the correct password. */