1117259Sache/* 2117259Sache * Copyright (c) 2001 Proofpoint, Inc. and its suppliers. 3117259Sache * All rights reserved. 4117259Sache * 5117259Sache * By using this file, you agree to the terms and conditions set 6117259Sache * forth in the LICENSE file which can be found at the top level of 7117259Sache * the sendmail distribution. 8117259Sache * 9174990Sache */ 10117259Sache 11117259Sache/* 12117259Sache** This program checks to see if your version of setgid works. 13117259Sache** Compile it, make it set-group-ID guest, and run it as yourself (NOT as 14117259Sache** root and not as member of the group guest). 15117259Sache** 16117259Sache** Compilation is trivial -- just "cc t_setgid.c". Make it set-group-ID, 17117259Sache** guest and then execute it as a non-root user. 18117259Sache*/ 19117259Sache 20117259Sache#include <sys/types.h> 21117259Sache#include <unistd.h> 22117259Sache#include <stdio.h> 23117259Sache 24174990Sache#ifndef lint 25117259Sachestatic char id[] = "@(#)$Id: t_setgid.c,v 1.7 2013-11-22 20:52:01 ca Exp $"; 26117259Sache#endif /* ! lint */ 27117259Sache 28117259Sachestatic void 29117259Sacheprintgids(str, r, e) 30117259Sache char *str; 31117259Sache gid_t r, e; 32117259Sache{ 33117259Sache printf("%s (should be %d/%d): r/egid=%d/%d\n", str, (int) r, (int) e, 34117259Sache (int) getgid(), (int) getegid()); 35117259Sache} 36117259Sache 37117259Sacheint 38117259Sachemain(argc, argv) 39174990Sache int argc; 40117259Sache char **argv; 41117259Sache{ 42117259Sache int fail = 0; 43117259Sache int res; 44117259Sache gid_t realgid = getgid(); 45117259Sache gid_t effgid = getegid(); 46117259Sache 47117259Sache printgids("initial gids", realgid, effgid); 48117259Sache 49174990Sache if (effgid == realgid) 50117259Sache { 51117259Sache printf("SETUP ERROR: re-run set-group-ID guest\n"); 52117259Sache exit(1); 53117259Sache } 54117259Sache 55117259Sache#if SM_CONF_SETREGID 56117259Sache res = setregid(effgid, effgid); 57117259Sache#else /* SM_CONF_SETREGID */ 58117259Sache res = setgid(effgid); 59117259Sache#endif /* SM_CONF_SETREGID */ 60117259Sache 61117259Sache printf("setgid(%d)=%d %s\n", (int) effgid, res, 62117259Sache res < 0 ? "failure" : "ok"); 63117259Sache#if SM_CONF_SETREGID 64117259Sache printgids("after setregid()", effgid, effgid); 65117259Sache#else /* SM_CONF_SETREGID */ 66117259Sache printgids("after setgid()", effgid, effgid); 67117259Sache#endif /* SM_CONF_SETREGID */ 68117259Sache 69117259Sache if (getegid() != effgid) 70117259Sache { 71117259Sache fail++; 72117259Sache printf("MAYDAY! Wrong effective gid\n"); 73117259Sache } 74117259Sache 75117259Sache if (getgid() != effgid) 76117259Sache { 77117259Sache fail++; 78117259Sache printf("MAYDAY! Wrong real gid\n"); 79117259Sache } 80117259Sache 81117259Sache /* do activity here */ 82117259Sache if (setgid(0) == 0) 83174990Sache { 84117259Sache fail++; 85117259Sache printf("MAYDAY! setgid(0) succeeded (should have failed)\n"); 86117259Sache } 87117259Sache else 88117259Sache { 89117259Sache printf("setgid(0) failed (this is correct)\n"); 90117259Sache } 91117259Sache printgids("after setgid(0)", effgid, effgid); 92117259Sache 93117259Sache if (getegid() != effgid) 94117259Sache { 95117259Sache fail++; 96117259Sache printf("MAYDAY! Wrong effective gid\n"); 97117259Sache } 98117259Sache if (getgid() != effgid) 99117259Sache { 100117259Sache fail++; 101117259Sache printf("MAYDAY! Wrong real gid\n"); 102117259Sache } 103117259Sache printf("\n"); 104117259Sache 105117259Sache if (fail > 0) 106 { 107 printf("\nThis system cannot use %s to set the real gid to the effective gid\nand clear the saved gid.\n", 108#if SM_CONF_SETREGID 109 "setregid" 110#else /* SM_CONF_SETREGID */ 111 "setgid" 112#endif /* SM_CONF_SETREGID */ 113 ); 114 exit(1); 115 } 116 117 printf("\nIt is possible to use setgid on this system\n"); 118 exit(0); 119} 120