1 /*
2 * Check decoding of SO_PEERCRED socket option.
3 *
4 * Copyright (c) 2017 Dmitry V. Levin <ldv@altlinux.org>
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 * 3. The name of the author may not be used to endorse or promote products
16 * derived from this software without specific prior written permission.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
19 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
20 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
21 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
22 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
23 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
24 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
25 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
26 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
27 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28 */
29
30 #include "tests.h"
31
32 #include <stddef.h>
33 #include <stdio.h>
34 #include <sys/socket.h>
35 #include <unistd.h>
36
37 #include "print_fields.h"
38
39 static const char *errstr;
40
41 static int
get_peercred(int fd,void * val,socklen_t * len)42 get_peercred(int fd, void *val, socklen_t *len)
43 {
44 int rc = getsockopt(fd, SOL_SOCKET, SO_PEERCRED, val, len);
45 errstr = sprintrc(rc);
46 return rc;
47 }
48
49 int
main(void)50 main(void)
51 {
52 TAIL_ALLOC_OBJECT_CONST_PTR(struct ucred, peercred);
53 TAIL_ALLOC_OBJECT_CONST_PTR(socklen_t, len);
54
55 int sv[2];
56 if (socketpair(AF_UNIX, SOCK_STREAM, 0, sv))
57 perror_msg_and_skip("socketpair AF_UNIX SOCK_STREAM");
58
59 /* classic getsockopt */
60 *len = sizeof(*peercred);
61 get_peercred(sv[0], peercred, len);
62 printf("getsockopt(%d, SOL_SOCKET, SO_PEERCRED", sv[0]);
63 PRINT_FIELD_D(", {", *peercred, pid);
64 PRINT_FIELD_UID(", ", *peercred, uid);
65 PRINT_FIELD_UID(", ", *peercred, gid);
66 printf("}, [%d]) = %s\n", *len, errstr);
67
68 int fd = socket(AF_UNIX, SOCK_STREAM, 0);
69 if (fd < 0)
70 perror_msg_and_skip("socket AF_UNIX SOCK_STREAM");
71
72 /* getsockopt with optlen larger than necessary - shortened */
73 *len = sizeof(*peercred) + 1;
74 get_peercred(fd, peercred, len);
75 printf("getsockopt(%d, SOL_SOCKET, SO_PEERCRED", fd);
76 PRINT_FIELD_D(", {", *peercred, pid);
77 PRINT_FIELD_UID(", ", *peercred, uid);
78 PRINT_FIELD_UID(", ", *peercred, gid);
79 printf("}, [%u->%d]) = %s\n",
80 (unsigned int) sizeof(*peercred) + 1, *len, errstr);
81
82 /* getsockopt with optlen smaller than usual - truncated to ucred.pid */
83 *len = sizeof(peercred->pid);
84 get_peercred(fd, peercred, len);
85 printf("getsockopt(%d, SOL_SOCKET, SO_PEERCRED", fd);
86 PRINT_FIELD_D(", {", *peercred, pid);
87 printf("}, [%d]) = %s\n", *len, errstr);
88
89 /* getsockopt with optlen smaller than usual - truncated to ucred.uid */
90 *len = offsetof(struct ucred, gid);
91 get_peercred(fd, peercred, len);
92 printf("getsockopt(%d, SOL_SOCKET, SO_PEERCRED", fd);
93 PRINT_FIELD_D(", {", *peercred, pid);
94 PRINT_FIELD_UID(", ", *peercred, uid);
95 printf("}, [%d]) = %s\n", *len, errstr);
96
97 /* getsockopt with optlen larger than usual - truncated to raw */
98 *len = sizeof(*peercred) - 1;
99 get_peercred(fd, peercred, len);
100 printf("getsockopt(%d, SOL_SOCKET, SO_PEERCRED, ", fd);
101 print_quoted_hex(peercred, *len);
102 printf(", [%d]) = %s\n", *len, errstr);
103
104 /* getsockopt optval EFAULT */
105 *len = sizeof(*peercred);
106 get_peercred(fd, &peercred->uid, len);
107 printf("getsockopt(%d, SOL_SOCKET, SO_PEERCRED, %p, [%d]) = %s\n",
108 fd, &peercred->uid, *len, errstr);
109
110 /* getsockopt optlen EFAULT */
111 get_peercred(fd, peercred, len + 1);
112 printf("getsockopt(%d, SOL_SOCKET, SO_PEERCRED, %p, %p) = %s\n",
113 fd, peercred, len + 1, errstr);
114
115 puts("+++ exited with 0 +++");
116 return 0;
117 }
118