xref: /freebsd/lib/libifconfig/libifconfig_carp.c (revision 59c8e88e72633afbc47a4ace0d2170d00d51f7dc)
1 /*
2  * Copyright (c) 1983, 1993
3  *  The Regents of the University of California.  All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. Neither the name of the University nor the names of its contributors
14  *    may be used to endorse or promote products derived from this software
15  *    without specific prior written permission.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  */
29 #include <sys/param.h>
30 #include <sys/ioctl.h>
31 
32 #include <net/if.h>
33 #include <netinet/ip_carp.h>
34 #include <netinet/ip_carp_nl.h>
35 
36 #include <netlink/netlink.h>
37 #include <netlink/netlink_generic.h>
38 #include <netlink/netlink_snl.h>
39 #include <netlink/netlink_snl_generic.h>
40 #include <netlink/netlink_snl_route.h>
41 
42 #include <string.h>
43 #include <strings.h>
44 
45 #include "libifconfig.h"
46 #include "libifconfig_internal.h"
47 
48 #include <stdio.h>
49 
50 #define	_OUT(_field)	offsetof(struct ifconfig_carp, _field)
51 static struct snl_attr_parser ap_carp_get[] = {
52 	{ .type = CARP_NL_VHID, .off = _OUT(carpr_vhid), .cb = snl_attr_get_uint32 },
53 	{ .type = CARP_NL_STATE, .off = _OUT(carpr_state), .cb = snl_attr_get_uint32 },
54 	{ .type = CARP_NL_ADVBASE, .off = _OUT(carpr_advbase), .cb = snl_attr_get_int32 },
55 	{ .type = CARP_NL_ADVSKEW, .off = _OUT(carpr_advskew), .cb = snl_attr_get_int32 },
56 	{ .type = CARP_NL_KEY, .off = _OUT(carpr_key), .cb = snl_attr_copy_string, .arg_u32 = CARP_KEY_LEN },
57 	{ .type = CARP_NL_ADDR, .off = _OUT(carpr_addr), .cb = snl_attr_get_in_addr },
58 	{ .type = CARP_NL_ADDR6, .off = _OUT(carpr_addr6), .cb = snl_attr_get_in6_addr },
59 };
60 #undef _OUT
61 
62 SNL_DECLARE_GENL_PARSER(carp_get_parser, ap_carp_get);
63 
64 static int
65 _ifconfig_carp_get(ifconfig_handle_t *h, const char *name,
66     struct ifconfig_carp *carp, size_t ncarp, uint32_t vhid)
67 {
68 	struct snl_state ss = {};
69 	struct snl_errmsg_data e = {};
70 	struct snl_writer nw;
71 	struct nlmsghdr *hdr;
72 	size_t i = 0;
73 	uint32_t seq_id;
74 	int family_id;
75 
76 	ifconfig_error_clear(h);
77 
78 	bzero(carp, sizeof(*carp) * ncarp);
79 
80 	if (! snl_init(&ss, NETLINK_GENERIC)) {
81 		ifconfig_error(h, NETLINK, ENOTSUP);
82 		return (-1);
83 	}
84 
85 	snl_init_writer(&ss, &nw);
86 
87 	family_id = snl_get_genl_family(&ss, CARP_NL_FAMILY_NAME);
88 	if (family_id == 0) {
89 		ifconfig_error(h, NETLINK, EPROTONOSUPPORT);
90 		goto out;
91 	}
92 
93 	hdr = snl_create_genl_msg_request(&nw, family_id, CARP_NL_CMD_GET);
94 	hdr->nlmsg_flags |= NLM_F_DUMP;
95 
96 	snl_add_msg_attr_string(&nw, CARP_NL_IFNAME, name);
97 
98 	if (vhid != 0)
99 		snl_add_msg_attr_u32(&nw, CARP_NL_VHID, vhid);
100 
101 	hdr = snl_finalize_msg(&nw);
102 	if (hdr == NULL) {
103 		ifconfig_error(h, NETLINK, ENOMEM);
104 		goto out;
105 	}
106 	seq_id = hdr->nlmsg_seq;
107 	if (! snl_send_message(&ss, hdr)) {
108 		ifconfig_error(h, NETLINK, EIO);
109 		goto out;
110 	}
111 
112 	while ((hdr = snl_read_reply_multi(&ss, seq_id, &e)) != NULL) {
113 		if (e.error != 0) {
114 			ifconfig_error(h, NETLINK, e.error);
115 			break;
116 		}
117 
118 		if (i >= ncarp) {
119 			ifconfig_error(h, NETLINK, E2BIG);
120 			break;
121 		}
122 
123 		memset(&carp[i], 0, sizeof(carp[0]));
124 		if (! snl_parse_nlmsg(&ss, hdr, &carp_get_parser, &carp[i]))
125 			continue;
126 
127 		i++;
128 		carp[0].carpr_count = i;
129 
130 		if (i > ncarp) {
131 			ifconfig_error(h, NETLINK, E2BIG);
132 			break;
133 		}
134 	}
135 
136 out:
137 	snl_free(&ss);
138 
139 	return (h->error.errcode ? -1 : 0);
140 }
141 
142 int
143 ifconfig_carp_set_info(ifconfig_handle_t *h, const char *name,
144     const struct ifconfig_carp *carpr)
145 {
146 	struct snl_state ss = {};
147 	struct snl_writer nw;
148 	struct nlmsghdr *hdr;
149 	int family_id;
150 	uint32_t seq_id;
151 
152 	ifconfig_error_clear(h);
153 
154 	if (! snl_init(&ss, NETLINK_GENERIC)) {
155 		ifconfig_error(h, NETLINK, ENOTSUP);
156 		return (-1);
157 	}
158 
159 	snl_init_writer(&ss, &nw);
160 
161 	family_id = snl_get_genl_family(&ss, CARP_NL_FAMILY_NAME);
162 	if (family_id == 0) {
163 		ifconfig_error(h, NETLINK, EPROTONOSUPPORT);
164 		return (-1);
165 	}
166 	hdr = snl_create_genl_msg_request(&nw, family_id, CARP_NL_CMD_SET);
167 
168 	snl_add_msg_attr_u32(&nw, CARP_NL_VHID, carpr->carpr_vhid);
169 	snl_add_msg_attr_u32(&nw, CARP_NL_STATE, carpr->carpr_state);
170 	snl_add_msg_attr_s32(&nw, CARP_NL_ADVBASE, carpr->carpr_advbase);
171 	snl_add_msg_attr_s32(&nw, CARP_NL_ADVSKEW, carpr->carpr_advskew);
172 	snl_add_msg_attr_string(&nw, CARP_NL_IFNAME, name);
173 	snl_add_msg_attr(&nw, CARP_NL_ADDR, sizeof(carpr->carpr_addr),
174 	    &carpr->carpr_addr);
175 	snl_add_msg_attr(&nw, CARP_NL_ADDR6, sizeof(carpr->carpr_addr6),
176 	    &carpr->carpr_addr6);
177 	snl_add_msg_attr_string(&nw, CARP_NL_KEY, carpr->carpr_key);
178 
179 	hdr = snl_finalize_msg(&nw);
180 	if (hdr == NULL) {
181 		ifconfig_error(h, NETLINK, ENOMEM);
182 		goto out;
183 	}
184 
185 	seq_id = hdr->nlmsg_seq;
186 	if (! snl_send_message(&ss, hdr)) {
187 		ifconfig_error(h, NETLINK, EIO);
188 		goto out;
189 	}
190 
191 	struct snl_errmsg_data e = { };
192 	if (! snl_read_reply_code(&ss, seq_id, &e))
193 		ifconfig_error(h, NETLINK, e.error);
194 
195 out:
196 	snl_free(&ss);
197 
198 	return (h->error.errcode ? -1 : 0);
199 }
200 
201 int
202 ifconfig_carp_get_vhid(ifconfig_handle_t *h, const char *name,
203     struct ifconfig_carp *carp, uint32_t vhid)
204 {
205 	return (_ifconfig_carp_get(h, name, carp, 1, vhid));
206 }
207 
208 int
209 ifconfig_carp_get_info(ifconfig_handle_t *h, const char *name,
210     struct ifconfig_carp *carp, size_t ncarp)
211 {
212 	return (_ifconfig_carp_get(h, name, carp, ncarp, 0));
213 }
214