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/* Written by Menno Duursma for use with xbill */
/*
* This program is free software. It comes without any warranty.
* Granted WTFPL, Version 2, as published by Sam Hocevar. See
* http://sam.zoy.org/wtfpl/COPYING for more details.
*/
/*
* Per default xbill sets its score file world writable
* which obviously allows cheating ones hi-score :-(
* Probably this came about since GTK+ doesn't allow setgid?
*
* In the install-script we move xbill to xbill-bin and install
* this here wrapper thing as xbill, with setuid and video group
* executable filesystem perms. Here we change groups to games.
*
* We should now be able make /var/xbill group-writable only...
*/
#include <stdlib.h>
#include <stdio.h>
#include <unistd.h>
#include <errno.h>
#include <string.h>
#include <grp.h>
int main(int argc, char *argv[], char *envp[])
{
/*
* hardcoded path/program to exec
* and group to run under
*/
char prog[] = "/usr/bin/xbill-bin";
char grpname[] = "games";
struct group *grp;
errno = 0;
/* get our gid */
grp = getgrnam(grpname);
if (grp == NULL) {
fprintf(stderr, "Error: getgrnam(%s) - %s\n",
grpname,
strerror(errno));
exit(EXIT_FAILURE);
}
/* drop to the gid */
if (setgid(grp->gr_gid)) {
fprintf(stderr, "Error: setgid(%d) - %s\n",
grp->gr_gid,
strerror(errno));
exit(EXIT_FAILURE);
}
/* drop back to calling uid */
if (setuid(getuid())) {
fprintf(stderr, "Error: setuid(%d) - %s\n",
getuid(),
strerror(errno));
exit(EXIT_FAILURE);
}
/* tell the viewers wat is going to happen */
fprintf(stderr, "Starting %s with uid = %d, gid = %d\n",
prog,
getuid(),
getgid());
/* fire it up */
if (execve(prog, argv, envp) == -1) {
fprintf(stderr, "Error: execve(%s, argv, envp) - %s\n",
prog,
strerror(errno));
exit(EXIT_FAILURE);
}
return EXIT_SUCCESS;
}
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