1/*	$OpenBSD: pfe_route.c,v 1.14 2023/06/29 16:24:53 claudio Exp $	*/
2
3/*
4 * Copyright (c) 2009 - 2011 Reyk Floeter <reyk@openbsd.org>
5 *
6 * Permission to use, copy, modify, and distribute this software for any
7 * purpose with or without fee is hereby granted, provided that the above
8 * copyright notice and this permission notice appear in all copies.
9 *
10 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
11 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
12 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
13 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
14 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
15 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
16 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
17 */
18
19#include <sys/types.h>
20#include <sys/queue.h>
21#include <sys/socket.h>
22#include <sys/uio.h>
23
24#include <netinet/in.h>
25#include <net/route.h>
26#include <arpa/inet.h>
27
28#include <limits.h>
29#include <stddef.h>
30#include <stdio.h>
31#include <unistd.h>
32#include <string.h>
33#include <errno.h>
34
35#include "relayd.h"
36
37void
38init_routes(struct relayd *env)
39{
40	u_int	 rtfilter;
41
42	if (!(env->sc_conf.flags & F_NEEDRT))
43		return;
44
45	if ((env->sc_rtsock = socket(AF_ROUTE, SOCK_RAW, 0)) == -1)
46		fatal("%s: failed to open routing socket", __func__);
47
48	rtfilter = ROUTE_FILTER(0);
49	if (setsockopt(env->sc_rtsock, AF_ROUTE, ROUTE_MSGFILTER,
50	    &rtfilter, sizeof(rtfilter)) == -1)
51		fatal("%s: ROUTE_MSGFILTER", __func__);
52}
53
54void
55sync_routes(struct relayd *env, struct router *rt)
56{
57	struct netroute		*nr;
58	struct host		*host;
59	char			 buf[HOST_NAME_MAX+1];
60	struct ctl_netroute	 crt;
61
62	if (!(env->sc_conf.flags & F_NEEDRT))
63		return;
64
65	TAILQ_FOREACH(nr, &rt->rt_netroutes, nr_entry) {
66		print_host(&nr->nr_conf.ss, buf, sizeof(buf));
67		TAILQ_FOREACH(host, &rt->rt_gwtable->hosts, entry) {
68			if (host->up == HOST_UNKNOWN)
69				continue;
70
71			log_debug("%s: "
72			    "router %s route %s/%d gateway %s %s priority %d",
73			    __func__,
74			    rt->rt_conf.name, buf, nr->nr_conf.prefixlen,
75			    host->conf.name,
76			    HOST_ISUP(host->up) ? "up" : "down",
77			    host->conf.priority);
78
79			crt.up = host->up;
80			memcpy(&crt.nr, &nr->nr_conf, sizeof(nr->nr_conf));
81			memcpy(&crt.host, &host->conf, sizeof(host->conf));
82			memcpy(&crt.rt, &rt->rt_conf, sizeof(rt->rt_conf));
83
84			proc_compose(env->sc_ps, PROC_PARENT,
85			    IMSG_RTMSG, &crt, sizeof(crt));
86		}
87	}
88}
89
90static void
91pfe_apply_prefixlen(struct sockaddr_storage *ss, int af, int len)
92{
93	int q, r, off;
94	uint8_t *b = (uint8_t *)ss;
95
96	q = len >> 3;
97	r = len & 7;
98
99	bzero(ss, sizeof(*ss));
100	ss->ss_family = af;
101	switch (af) {
102	case AF_INET:
103		ss->ss_len = sizeof(struct sockaddr_in);
104		off = offsetof(struct sockaddr_in, sin_addr);
105		break;
106	case AF_INET6:
107		ss->ss_len = sizeof(struct sockaddr_in6);
108		off = offsetof(struct sockaddr_in6, sin6_addr);
109		break;
110	default:
111		fatal("%s: invalid address family", __func__);
112	}
113	if (q > 0)
114		memset(b + off, 0xff, q);
115	if (r > 0)
116		b[off + q] = (0xff00 >> r) & 0xff;
117}
118
119#define ROUNDUP(a) \
120	((a) > 0 ? (1 + (((a) - 1) | (sizeof(long) - 1))) : sizeof(long))
121
122int
123pfe_route(struct relayd *env, struct ctl_netroute *crt)
124{
125	struct iovec			 iov[5];
126	struct rt_msghdr		 hdr;
127	struct sockaddr_storage		 dst, gw, mask, label;
128	struct sockaddr_rtlabel		*sr = (struct sockaddr_rtlabel *)&label;
129	int				 iovcnt = 0;
130	char				*gwname;
131
132	bzero(&hdr, sizeof(hdr));
133	hdr.rtm_msglen = sizeof(hdr);
134	hdr.rtm_version = RTM_VERSION;
135	hdr.rtm_type = HOST_ISUP(crt->up) ? RTM_ADD : RTM_DELETE;
136	hdr.rtm_flags = RTF_STATIC | RTF_GATEWAY | RTF_MPATH;
137	hdr.rtm_seq = env->sc_rtseq++;
138	hdr.rtm_addrs = RTA_DST | RTA_GATEWAY | RTA_NETMASK;
139	hdr.rtm_tableid = crt->rt.rtable;
140	hdr.rtm_priority = crt->host.priority;
141
142	iov[iovcnt].iov_base = &hdr;
143	iov[iovcnt++].iov_len = sizeof(hdr);
144
145	dst = crt->nr.ss;
146	gw = crt->host.ss;
147	gwname = crt->host.name;
148	pfe_apply_prefixlen(&mask, dst.ss_family, crt->nr.prefixlen);
149
150	iov[iovcnt].iov_base = &dst;
151	iov[iovcnt++].iov_len = ROUNDUP(dst.ss_len);
152	hdr.rtm_msglen += ROUNDUP(dst.ss_len);
153
154	iov[iovcnt].iov_base = &gw;
155	iov[iovcnt++].iov_len = ROUNDUP(gw.ss_len);
156	hdr.rtm_msglen += ROUNDUP(gw.ss_len);
157
158	iov[iovcnt].iov_base = &mask;
159	iov[iovcnt++].iov_len = ROUNDUP(mask.ss_len);
160	hdr.rtm_msglen += ROUNDUP(mask.ss_len);
161
162	if (strlen(crt->rt.label)) {
163		sr->sr_len = sizeof(*sr);
164		strlcpy(sr->sr_label, crt->rt.label, sizeof(sr->sr_label));
165
166		iov[iovcnt].iov_base = &label;
167		iov[iovcnt++].iov_len = ROUNDUP(label.ss_len);
168		hdr.rtm_msglen += ROUNDUP(label.ss_len);
169		hdr.rtm_addrs |= RTA_LABEL;
170	}
171
172 retry:
173	if (writev(env->sc_rtsock, iov, iovcnt) == -1) {
174		switch (errno) {
175		case EEXIST:
176		case ESRCH:
177			if (hdr.rtm_type == RTM_ADD) {
178				hdr.rtm_type = RTM_CHANGE;
179				goto retry;
180			} else if (hdr.rtm_type == RTM_DELETE) {
181				/* Ignore */
182				break;
183			}
184			/* FALLTHROUGH */
185		default:
186			goto bad;
187		}
188	}
189
190	log_debug("%s: gateway %s %s", __func__, gwname,
191	    HOST_ISUP(crt->up) ? "added" : "deleted");
192
193	return (0);
194
195 bad:
196	log_debug("%s: failed to %s gateway %s: %d %s", __func__,
197	    HOST_ISUP(crt->up) ? "add" : "delete", gwname,
198	    errno, strerror(errno));
199
200	return (-1);
201}
202