diff options
Diffstat (limited to 'slock.c')
| -rw-r--r-- | slock.c | 36 |
1 files changed, 28 insertions, 8 deletions
@@ -44,6 +44,21 @@ die(const char *errstr, ...) { exit(EXIT_FAILURE); } +#ifdef __linux__ +#include <fcntl.h> + +static void +dontkillme(void) { + int fd; + + fd = open("/proc/self/oom_score_adj", O_WRONLY); + if (fd < 0 && errno == ENOENT) + return; + if (fd < 0 || write(fd, "-1000\n", 6) != 6 || close(fd) != 0) + die("cannot disable the out-of-memory killer for this process\n"); +} +#endif + #ifndef HAVE_BSD_AUTH static const char * getpw(void) { /* only run as root */ @@ -52,7 +67,7 @@ getpw(void) { /* only run as root */ pw = getpwuid(getuid()); if(!pw) - die("slock: cannot retrieve password entry (make sure to suid or sgid slock)"); + die("slock: cannot retrieve password entry (make sure to suid or sgid slock)\n"); endpwent(); rval = pw->pw_passwd; @@ -68,8 +83,9 @@ getpw(void) { /* only run as root */ #endif /* drop privileges */ - if(setgid(pw->pw_gid) < 0 || setuid(pw->pw_uid) < 0) - die("slock: cannot 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 @@ -114,9 +130,9 @@ readpw(Display *dpy, const char *pws) #ifdef HAVE_BSD_AUTH running = !auth_userokay(getlogin(), NULL, "auth-xlock", passwd); #else - running = strcmp(crypt(passwd, pws), pws); + running = !!strcmp(crypt(passwd, pws), pws); #endif - if(running != False) + if(running) XBell(dpy, 100); len = 0; break; @@ -244,20 +260,24 @@ main(int argc, char **argv) { else if(argc != 1) usage(); +#ifdef __linux__ + dontkillme(); +#endif + if(!getpwuid(getuid())) - die("slock: no passwd entry for you"); + die("slock: no passwd entry for you\n"); #ifndef HAVE_BSD_AUTH pws = getpw(); #endif if(!(dpy = XOpenDisplay(0))) - die("slock: cannot open display"); + die("slock: cannot open display\n"); /* Get the number of screens in display "dpy" and blank them all. */ nscreens = ScreenCount(dpy); locks = malloc(sizeof(Lock *) * nscreens); if(locks == NULL) - die("slock: malloc: %s", strerror(errno)); + die("slock: malloc: %s\n", strerror(errno)); int nlocks = 0; for(screen = 0; screen < nscreens; screen++) { if ( (locks[screen] = lockscreen(dpy, screen)) != NULL) |