1 /*
2 * Copyright (c) 1999-2001 Proofpoint, Inc. and its suppliers.
3 * All rights reserved.
4 *
5 * By using this file, you agree to the terms and conditions set
6 * forth in the LICENSE file which can be found at the top level of
7 * the sendmail distribution.
8 *
9 */
10
11 /*
12 ** This program checks to see if your version of seteuid works.
13 ** Compile it, make it set-user-ID root, and run it as yourself (NOT as
14 ** root). If it won't compile or outputs any MAYDAY messages, don't
15 ** define USESETEUID in conf.h.
16 **
17 ** NOTE: It is not sufficient to have seteuid in your library.
18 ** You must also have saved uids that function properly.
19 **
20 ** Compilation is trivial -- just "cc t_seteuid.c". Make it set-user-ID
21 ** root and then execute it as a non-root user.
22 */
23
24 #include <sys/types.h>
25 #include <unistd.h>
26 #include <stdio.h>
27 #include <stdlib.h>
28
29 #ifndef lint
30 static char id[] = "@(#)$Id: t_seteuid.c,v 8.9 2013-11-22 20:52:01 ca Exp $";
31 #endif
32
33 #ifdef __hpux
34 # define seteuid(e) setresuid(-1, e, -1)
35 #endif
36
37 static void
printuids(str,r,e)38 printuids(str, r, e)
39 char *str;
40 uid_t r, e;
41 {
42 printf("%s (should be %d/%d): r/euid=%d/%d\n", str, (int) r, (int) e,
43 (int) getuid(), (int) geteuid());
44 }
45
46 int
main(argc,argv)47 main(argc, argv)
48 int argc;
49 char **argv;
50 {
51 int fail = 0;
52 uid_t realuid = getuid();
53
54 printuids("initial uids", realuid, 0);
55
56 if (geteuid() != 0)
57 {
58 printf("SETUP ERROR: re-run set-user-ID root\n");
59 exit(1);
60 }
61
62 if (getuid() == 0)
63 {
64 printf("SETUP ERROR: must be run by a non-root user\n");
65 exit(1);
66 }
67
68 if (seteuid(1) < 0)
69 printf("seteuid(1) failure\n");
70 printuids("after seteuid(1)", realuid, 1);
71
72 if (geteuid() != 1)
73 {
74 fail++;
75 printf("MAYDAY! Wrong effective uid\n");
76 }
77
78 /* do activity here */
79
80 if (seteuid(0) < 0)
81 {
82 fail++;
83 printf("seteuid(0) failure\n");
84 }
85 printuids("after seteuid(0)", realuid, 0);
86
87 if (geteuid() != 0)
88 {
89 fail++;
90 printf("MAYDAY! Wrong effective uid\n");
91 }
92 if (getuid() != realuid)
93 {
94 fail++;
95 printf("MAYDAY! Wrong real uid\n");
96 }
97 printf("\n");
98
99 if (seteuid(2) < 0)
100 {
101 fail++;
102 printf("seteuid(2) failure\n");
103 }
104 printuids("after seteuid(2)", realuid, 2);
105
106 if (geteuid() != 2)
107 {
108 fail++;
109 printf("MAYDAY! Wrong effective uid\n");
110 }
111
112 /* do activity here */
113
114 if (seteuid(0) < 0)
115 {
116 fail++;
117 printf("seteuid(0) failure\n");
118 }
119 printuids("after seteuid(0)", realuid, 0);
120
121 if (geteuid() != 0)
122 {
123 fail++;
124 printf("MAYDAY! Wrong effective uid\n");
125 }
126 if (getuid() != realuid)
127 {
128 fail++;
129 printf("MAYDAY! Wrong real uid\n");
130 }
131
132 if (fail)
133 {
134 printf("\nThis system cannot use seteuid\n");
135 exit(1);
136 }
137
138 printf("\nIt is safe to define USESETEUID on this system\n");
139 exit(0);
140 }
141