1/*
2 * Check decoding of SIOCGIFCONF command of ioctl syscall.
3 *
4 * Copyright (c) 2016 Eugene Syromyatnikov <evgsyr@gmail.com>
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 <stdbool.h>
33#include <stdio.h>
34#include <string.h>
35
36#include <arpa/inet.h>
37#include <net/if.h>
38#include <sys/ioctl.h>
39#include <sys/socket.h>
40
41#define MAX_STRLEN 1
42
43static void
44print_ifc_len(int val)
45{
46	if (val % (int) sizeof(struct ifreq))
47		printf("%d", val);
48	else
49		printf("%d * sizeof(struct ifreq)",
50		       val / (int) sizeof(struct ifreq));
51}
52
53static void
54print_ifconf(struct ifconf *ifc, int in_len, char *in_buf, long rc)
55{
56	if (in_buf) {
57		printf("{ifc_len=");
58		print_ifc_len(in_len);
59
60		if (in_len != ifc->ifc_len) {
61			printf(" => ");
62			print_ifc_len(ifc->ifc_len);
63		}
64	} else {
65		printf("{ifc_len=");
66		print_ifc_len(ifc->ifc_len);
67	}
68
69	printf(", ifc_buf=");
70
71	if ((rc < 0) || !in_buf) {
72		if (in_buf)
73			printf("%p", in_buf);
74		else
75			printf("NULL");
76	} else {
77		int i;
78
79		printf("[");
80		for (i = 0; i < (ifc->ifc_len) &&
81		    i < (int) (MAX_STRLEN * sizeof(struct ifreq));
82		    i += sizeof(struct ifreq)) {
83			struct ifreq *ifr = (struct ifreq *) (ifc->ifc_buf + i);
84			struct sockaddr_in *const sa_in =
85				(struct sockaddr_in *) &(ifr->ifr_addr);
86
87			if (i)
88				printf(", ");
89			printf("{ifr_name=\"%s\", ifr_addr={sa_family=AF_INET, "
90			       "sin_port=htons(%u), sin_addr=inet_addr(\"%s\")}"
91			       "}", ifr->ifr_name, ntohs(sa_in->sin_port),
92			       inet_ntoa(sa_in->sin_addr));
93		}
94
95		if ((size_t) (ifc->ifc_len - i) >= sizeof(struct ifreq))
96			printf(", ...");
97
98		printf("]");
99	}
100
101	printf("}");
102}
103
104static void
105gifconf_ioctl(int fd, struct ifconf *ifc, bool ifc_valid)
106{
107	const char * errstr;
108	int in_len;
109	char *in_buf;
110	long rc;
111
112	if (ifc_valid) {
113		in_len = ifc->ifc_len;
114		in_buf = ifc->ifc_buf;
115	}
116
117	rc = ioctl(fd, SIOCGIFCONF, ifc);
118	errstr = sprintrc(rc);
119
120	printf("ioctl(%d, SIOCGIFCONF, ", fd);
121	if (ifc_valid) {
122		print_ifconf(ifc, in_len, in_buf, rc);
123	} else {
124		if (ifc)
125			printf("%p", ifc);
126		else
127			printf("NULL");
128	}
129
130	printf(") = %s\n", errstr);
131}
132
133int
134main(int argc, char *argv[])
135{
136	struct ifreq *ifr = tail_alloc(2 * sizeof(*ifr));
137	struct ifconf *ifc = tail_alloc(sizeof(*ifc));
138
139	struct sockaddr_in addr;
140	int fd;
141
142	memset(&addr, 0, sizeof(addr));
143	addr.sin_family = AF_INET;
144	addr.sin_addr.s_addr = htonl(INADDR_LOOPBACK);
145
146	if ((fd = socket(AF_INET, SOCK_STREAM, 0)) < 0)
147		perror_msg_and_skip("socket AF_INET");
148
149	gifconf_ioctl(fd, NULL, false);
150	gifconf_ioctl(fd, ifc + 1, false);
151
152	ifc->ifc_len = 3141592653U;
153	ifc->ifc_buf = NULL;
154	gifconf_ioctl(fd, ifc, true);
155
156	ifc->ifc_len = 0;
157	ifc->ifc_buf = (char *) (ifr + 2);
158	gifconf_ioctl(fd, ifc, true);
159
160	ifc->ifc_len = 1;
161	ifc->ifc_buf = (char *) (ifr + 1);
162	gifconf_ioctl(fd, ifc, true);
163
164	ifc->ifc_len = 1 * sizeof(*ifr);
165	ifc->ifc_buf = (char *) (ifr + 1);
166	gifconf_ioctl(fd, ifc, true);
167
168	ifc->ifc_len = 2 * sizeof(*ifr);
169	ifc->ifc_buf = (char *) (ifr + 1);
170	gifconf_ioctl(fd, ifc, true);
171
172	ifc->ifc_len = 2 * sizeof(*ifr) + 2;
173	ifc->ifc_buf = (char *) ifr;
174	gifconf_ioctl(fd, ifc, true);
175
176	ifc->ifc_len = 3 * sizeof(*ifr) + 4;
177	ifc->ifc_buf = (char *) ifr;
178	gifconf_ioctl(fd, ifc, true);
179
180	puts("+++ exited with 0 +++");
181	return 0;
182}
183