1 /*
2  * This file is part of net-yy-unix strace test.
3  *
4  * Copyright (c) 2014-2016 Dmitry V. Levin <ldv@altlinux.org>
5  * Copyright (c) 2014-2018 The strace developers.
6  * All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  * 3. The name of the author may not be used to endorse or promote products
17  *    derived from this software without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
20  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
21  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
22  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
23  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
24  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
25  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
26  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
27  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
28  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
29  */
30 
31 #include "tests.h"
32 #include <assert.h>
33 #include <errno.h>
34 #include <stddef.h>
35 #include <stdint.h>
36 #include <string.h>
37 #include <unistd.h>
38 #include <sys/socket.h>
39 #include <sys/un.h>
40 #include "netlink.h"
41 #include <linux/sock_diag.h>
42 #include <linux/unix_diag.h>
43 
44 static void
send_query(const int fd)45 send_query(const int fd)
46 {
47 	struct sockaddr_nl nladdr = {
48 		.nl_family = AF_NETLINK
49 	};
50 	struct {
51 		struct nlmsghdr nlh;
52 		struct unix_diag_req udr;
53 	} req = {
54 		.nlh = {
55 			.nlmsg_len = sizeof(req),
56 			.nlmsg_type = SOCK_DIAG_BY_FAMILY,
57 			.nlmsg_flags = NLM_F_REQUEST | NLM_F_DUMP
58 		},
59 		.udr = {
60 			.sdiag_family = AF_UNIX,
61 			.udiag_states = -1,
62 			.udiag_show = UDIAG_SHOW_NAME | UDIAG_SHOW_PEER
63 		}
64 	};
65 	struct iovec iov = {
66 		.iov_base = &req,
67 		.iov_len = sizeof(req)
68 	};
69 	struct msghdr msg = {
70 		.msg_name = (void *) &nladdr,
71 		.msg_namelen = sizeof(nladdr),
72 		.msg_iov = &iov,
73 		.msg_iovlen = 1
74 	};
75 
76 	if (sendmsg(fd, &msg, 0) <= 0)
77 		perror_msg_and_skip("sendmsg");
78 }
79 
80 static void
check_responses(const int fd)81 check_responses(const int fd)
82 {
83 	static union {
84 		struct nlmsghdr hdr;
85 		long buf[8192 / sizeof(long)];
86 	} hdr_buf;
87 
88 	struct sockaddr_nl nladdr = {
89 		.nl_family = AF_NETLINK
90 	};
91 	struct iovec iov = {
92 		.iov_base = hdr_buf.buf,
93 		.iov_len = sizeof(hdr_buf.buf)
94 	};
95 	struct msghdr msg = {
96 		.msg_name = (void *) &nladdr,
97 		.msg_namelen = sizeof(nladdr),
98 		.msg_iov = &iov,
99 		.msg_iovlen = 1
100 	};
101 
102 	ssize_t ret = recvmsg(fd, &msg, 0);
103 	if (ret <= 0)
104 		perror_msg_and_skip("recvmsg");
105 
106 	struct nlmsghdr *h = &hdr_buf.hdr;
107 	if (!is_nlmsg_ok(h, ret))
108 		error_msg_and_skip("!is_nlmsg_ok");
109 	if (h->nlmsg_type == NLMSG_ERROR) {
110 		const struct nlmsgerr *err = NLMSG_DATA(h);
111 		if (h->nlmsg_len < NLMSG_LENGTH(sizeof(*err)))
112 			error_msg_and_skip("NLMSG_ERROR");
113 		errno = -err->error;
114 		perror_msg_and_skip("NLMSG_ERROR");
115 	}
116 	if (h->nlmsg_type != SOCK_DIAG_BY_FAMILY)
117 		error_msg_and_skip("unexpected nlmsg_type %u",
118 				   (unsigned) h->nlmsg_type);
119 
120 	const struct unix_diag_msg *diag = NLMSG_DATA(h);
121 	if (h->nlmsg_len < NLMSG_LENGTH(sizeof(*diag)))
122 		error_msg_and_skip("short response");
123 }
124 
125 #define SUN_PATH "netlink_unix_diag_socket"
main(void)126 int main(void)
127 {
128 	struct sockaddr_un addr = {
129 		.sun_family = AF_UNIX,
130 		.sun_path = SUN_PATH
131 	};
132 	socklen_t len = offsetof(struct sockaddr_un, sun_path) + sizeof(SUN_PATH);
133 
134 	close(0);
135 	close(1);
136 
137 	(void) unlink(SUN_PATH);
138 	if (socket(AF_UNIX, SOCK_STREAM, 0))
139 		perror_msg_and_skip("socket AF_UNIX");
140 	if (bind(0, (struct sockaddr *) &addr, len))
141 		perror_msg_and_skip("bind");
142 	if (listen(0, 5))
143 		perror_msg_and_skip("listen");
144 
145 	assert(unlink(SUN_PATH) == 0);
146 
147 	if (socket(AF_NETLINK, SOCK_RAW, NETLINK_SOCK_DIAG) != 1)
148 		perror_msg_and_skip("socket AF_NETLINK");
149 
150 	send_query(1);
151 	check_responses(1);
152 	return 0;
153 }
154