X-Git-Url: https://git.danieliu.xyz/?a=blobdiff_plain;f=slock.c;h=7127ebe0827460a4b6d9d71ea722b83e21a4ee7b;hb=22eba05f3683c12fa6a5f898d08c33704c9fbb73;hp=068227985bfa9bb5efd768a7af98dffe4ad26153;hpb=39fb855aa100c5a5a8b7f3b6cc1fbb2135fe7dde;p=slock.git diff --git a/slock.c b/slock.c index 0682279..7127ebe 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" @@ -46,8 +42,6 @@ typedef struct { static Lock **locks; static int nscreens; -static Bool running = True; -static Bool failure = False; static Bool rr; static int rrevbase; static int rrerrbase; @@ -90,20 +84,19 @@ dontkillme(void) } #endif -#ifndef HAVE_BSD_AUTH -/* only run as root */ static const char * getpw(void) { const char *rval; 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; @@ -111,35 +104,37 @@ getpw(void) if (rval[0] == 'x' && rval[1] == '\0') { struct spwd *sp; if (!(sp = getspnam(getenv("USER")))) - die("cannot retrieve shadow entry (make sure to suid or sgid slock)\n"); + die("slock: getspnam: cannot retrieve shadow entry (make sure to suid or sgid slock)\n"); rval = sp->sp_pwdp; } -#endif +#else + if (rval[0] == '*' && rval[1] == '\0') { +#ifdef __OpenBSD__ + if (!(pw = getpwnam_shadow(getenv("USER")))) + die("slock: getpwnam_shadow: cannot retrieve shadow entry (make sure to suid or sgid slock)\n"); + rval = 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; } -#endif static void -#ifdef HAVE_BSD_AUTH -readpw(Display *dpy) -#else readpw(Display *dpy, const char *pws) -#endif { char buf[32], passwd[256], *encrypted; - int num, screen; + int num, screen, running, failure; unsigned int len, color; KeySym ksym; XEvent ev; static int oldc = INIT; len = 0; - running = True; + running = 1; + failure = 0; /* As "slock" stands for "Simple X display locker", the DPMS settings * had been removed and you can set it with "xset" or some other @@ -164,15 +159,11 @@ readpw(Display *dpy, const char *pws) switch (ksym) { case XK_Return: passwd[len] = 0; -#ifdef HAVE_BSD_AUTH - running = !auth_userokay(getlogin(), NULL, "auth-slock", passwd); -#else errno = 0; if (!(encrypted = crypt(passwd, pws))) fprintf(stderr, "slock: crypt: %s\n", strerror(errno)); else running = !!strcmp(encrypted, pws); -#endif if (running) { XBell(dpy, 100); failure = True; @@ -253,7 +244,7 @@ lockscreen(Display *dpy, int screen) XSetWindowAttributes wa; Cursor invisible; - if (!running || dpy == NULL || screen < 0 || !(lock = malloc(sizeof(Lock)))) + if (dpy == NULL || screen < 0 || !(lock = malloc(sizeof(Lock)))) return NULL; lock->screen = screen; @@ -275,7 +266,7 @@ lockscreen(Display *dpy, int screen) 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 | @@ -321,9 +312,11 @@ usage(void) int main(int argc, char **argv) { -#ifndef HAVE_BSD_AUTH + struct passwd *pwd; + struct group *grp; + uid_t duid; + gid_t dgid; const char *pws; -#endif Display *dpy; int s, nlocks; @@ -335,28 +328,37 @@ 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 */ - 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 (!(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); @@ -376,7 +378,6 @@ main(int argc, char **argv) { /* did we manage to lock everything? */ if (nlocks != nscreens) { - running = 0; cleanup(dpy); return 1; } @@ -398,11 +399,7 @@ main(int argc, char **argv) { } /* 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);