1/*++ 2/* NAME 3/* set_ugid 3 4/* SUMMARY 5/* set real, effective and saved user and group attributes 6/* SYNOPSIS 7/* #include <set_ugid.h> 8/* 9/* void set_ugid(uid, gid) 10/* uid_t uid; 11/* gid_t gid; 12/* DESCRIPTION 13/* set_ugid() sets the real, effective and saved user and group process 14/* attributes and updates the process group access list to be just the 15/* user's primary group. This operation is irreversible. 16/* DIAGNOSTICS 17/* All system call errors are fatal. 18/* SEE ALSO 19/* setuid(2), setgid(2), setgroups(2) 20/* LICENSE 21/* .ad 22/* .fi 23/* The Secure Mailer license must be distributed with this software. 24/* AUTHOR(S) 25/* Wietse Venema 26/* IBM T.J. Watson Research 27/* P.O. Box 704 28/* Yorktown Heights, NY 10598, USA 29/*--*/ 30 31/* System library. */ 32 33#include <sys_defs.h> 34#include <unistd.h> 35#include <grp.h> 36#include <errno.h> 37 38/* Utility library. */ 39 40#include "msg.h" 41#include "set_ugid.h" 42 43/* set_ugid - set real, effective and saved user and group attributes */ 44 45void set_ugid(uid_t uid, gid_t gid) 46{ 47 int saved_errno = errno; 48 49 if (geteuid() != 0) 50 if (seteuid(0) < 0) 51 msg_fatal("seteuid(0): %m"); 52 if (setgid(gid) < 0) 53 msg_fatal("setgid(%ld): %m", (long) gid); 54 if (setgroups(1, &gid) < 0) 55 msg_fatal("setgroups(1, &%ld): %m", (long) gid); 56 if (setuid(uid) < 0) 57 msg_fatal("setuid(%ld): %m", (long) uid); 58 if (msg_verbose > 1) 59 msg_info("setugid: uid %ld gid %ld", (long) uid, (long) gid); 60 errno = saved_errno; 61} 62