xref: /netbsd-src/usr.sbin/ldpd/mpls_interface.c (revision daf6c4152fcddc27c445489775ed1f66ab4ea9a9)
1 /* $NetBSD: mpls_interface.c,v 1.5 2011/02/09 11:38:57 kefren Exp $ */
2 
3 /*-
4  * Copyright (c) 2010 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Mihai Chelaru <kefren@NetBSD.org>
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29  * POSSIBILITY OF SUCH DAMAGE.
30  */
31 
32 #include <arpa/inet.h>
33 #include <netinet/in.h>
34 #include <netmpls/mpls.h>
35 #include <net/route.h>
36 
37 #include <sys/param.h>
38 
39 #include <assert.h>
40 #include <stdio.h>
41 #include <string.h>
42 #include <stdlib.h>
43 #include <unistd.h>
44 
45 #include "ldp.h"
46 #include "ldp_peer.h"
47 #include "ldp_errors.h"
48 #include "tlv_stack.h"
49 #include "label.h"
50 #include "mpls_interface.h"
51 #include "mpls_routes.h"
52 
53 int
54 mpls_add_label(struct ldp_peer * p, struct rt_msg * inh_rg,
55     struct in_addr * addr, int len, int label, int rlookup)
56 {
57 	char            padd[20];
58 	int             kount = 0, rv;
59 	union sockunion *so_dest, *so_pref = NULL, *so_gate, *so_nexthop, *so_tag,
60 		*so_oldifa = NULL, *so_ifa;
61 	struct rt_msg   rg;
62 	struct rt_msg	*rgp = &rg;
63 	struct label	*lab;
64 
65 	strlcpy(padd, inet_ntoa(p->address), 20);
66 	debugp("Trying to add %s/%d as label %d to peer %s\n", inet_ntoa(*addr),
67 		len, label, padd);
68 
69 	/* Don't accept default route XXX: should be option-able */
70 	if (!len)
71 		return LDP_E_BAD_AF;
72 
73 	/* Is there a label mapping for this ? */
74 	if (ldp_peer_get_lm(p, addr, len) == NULL)
75 		return LDP_E_NOENT;
76 
77 	if (!inh_rg || (inh_rg->m_rtm.rtm_addrs & RTA_IFA) == 0) {
78 		/*
79 		 * XXX: Check if we have a route for that.
80 		 * Why the hell isn't kernel inserting the route immediatly ?
81 		 * let's loop until we have it..
82 		 */
83 
84 		if ((so_dest = make_inet_union(inet_ntoa(*addr))) == NULL)
85 			return LDP_E_MEMORY;
86 		if (len != 32 && (so_pref = from_cidr_to_union(len)) == NULL) {
87 			free(so_dest);
88 			return LDP_E_MEMORY;
89 		}
90 		do {
91 			if (kount == rlookup) {
92 				debugp("No route for this prefix\n");
93 				return LDP_E_NO_SUCH_ROUTE;
94 			}
95 			kount++;
96 			/* Last time give it a higher chance */
97 			if (kount == rlookup)
98 				usleep(5000);
99 
100 			rv = get_route(rgp, so_dest, so_pref, 1);
101 			if (rv != LDP_E_OK && len == 32)
102 				/* Host maybe ? */
103 				rv = get_route(rgp, so_dest, NULL, 1);
104 		} while (rv != LDP_E_OK);
105 
106 		free(so_dest);
107 		if (so_pref)
108 			free(so_pref);
109 
110 	} else
111 		rgp = inh_rg;
112 
113 	/* Check if it's an IPv4 route */
114 
115 	so_gate = (union sockunion *) rgp->m_space;
116 	so_gate = (union sockunion *)((char*)so_gate +
117 	    RT_ROUNDUP(so_gate->sa.sa_len));
118 	if (rgp->m_rtm.rtm_addrs & RTA_IFA) {
119 		int li = 1;
120 		so_oldifa = so_gate;
121 		if (rgp->m_rtm.rtm_addrs & RTA_NETMASK)
122 			li++;
123 		if (rgp->m_rtm.rtm_addrs & RTA_GENMASK)
124 			li++;
125 		if (rgp->m_rtm.rtm_addrs & RTA_IFP)
126 			li++;
127 		for (int i = 0; i < li; i++)
128 			so_oldifa = (union sockunion *)((char*)so_oldifa +
129 			    RT_ROUNDUP(so_oldifa->sa.sa_len));
130 	}
131 
132 	if (so_gate->sa.sa_family != AF_INET) {
133 		debugp("Failed at family check - only INET supoprted for now\n");
134 		return LDP_E_BAD_AF;
135 	}
136 
137 	/* Check if the address is bounded to the peer */
138 	if (check_ifaddr(p, &so_gate->sin.sin_addr) == NULL) {
139 		debugp("Failed at next-hop check\n");
140 		return LDP_E_ROUTE_ERROR;
141 	}
142 
143 	/* CHECK IF WE HAVE A BINDING FOR THAT */
144 	lab = label_get_by_prefix(addr, len);
145 
146 	/* We should have a label because we have a route */
147 	assert (lab);
148 
149 	if (lab->binding == MPLS_LABEL_IMPLNULL) {
150 		change_local_label(lab, get_free_local_label());
151 		if (!lab->binding) {
152 			fatalp("No more free labels !!!\n");
153 			return LDP_E_TOO_MANY_LABELS;
154 		}
155 	}
156 
157 	warnp("[mpls_add_label] Adding %s/%d as local binding %d, label %d"
158 	    " to peer %s\n",
159 		inet_ntoa(*addr), len, lab->binding, label, padd);
160 
161 	/* Modify existing label */
162 	lab->label = label;
163 	lab->p = p;
164 
165 	/* Add switching route */
166 	so_dest = make_mpls_union(lab->binding);
167 	so_nexthop = malloc(sizeof(*so_nexthop));
168 	if (!so_nexthop) {
169 		free(so_dest);
170 		fatalp("Out of memory\n");
171 		return LDP_E_MEMORY;
172 	}
173 	memcpy(so_nexthop, so_gate, so_gate->sa.sa_len);
174 	if ((so_tag = make_mpls_union(label)) == NULL) {
175 		free(so_dest);
176 		free(so_nexthop);
177 		fatalp("Out of memory\n");
178 		return LDP_E_MEMORY;
179 	}
180 	if (add_route(so_dest, NULL, so_nexthop, NULL, so_tag, FREESO, RTM_ADD) != LDP_E_OK)
181 		return LDP_E_ROUTE_ERROR;
182 
183 	/* Now, let's add tag to IPv4 route and point it to mpls interface */
184 	if ((so_dest = make_inet_union(inet_ntoa(*addr))) == NULL) {
185 		fatalp("Out of memory\n");
186 		return LDP_E_MEMORY;
187 	}
188 
189 	/* if prefixlen == 32 check if it's inserted as host
190  	* and treat it as host. It may also be set as /32 prefix
191  	* (thanks mlelstv for heads-up about this)
192  	*/
193 	if ((len == 32) && (rgp->m_rtm.rtm_flags & RTF_HOST))
194 		so_pref = NULL;
195 	else if ((so_pref = from_cidr_to_union(len)) == NULL) {
196 		free(so_dest);
197 		fatalp("Out of memory\n");
198 		return LDP_E_MEMORY;
199 	}
200 
201 	/* Add tag to route */
202 	so_nexthop = malloc(sizeof(*so_nexthop));
203 	if (!so_nexthop) {
204 		free(so_dest);
205 		if (so_pref != NULL)
206 			free(so_pref);
207 		fatalp("Out of memory\n");
208 		return LDP_E_MEMORY;
209 	}
210 	memcpy(so_nexthop, so_gate, so_gate->sa.sa_len);
211 	so_tag = make_mpls_union(label);
212 	if (so_oldifa != NULL) {
213 		so_ifa = malloc(sizeof(*so_ifa));
214 		if (so_ifa == NULL) {
215 			free(so_dest);
216 			if (so_pref != NULL)
217 				free(so_pref);
218 			free(so_tag);
219 			free(so_nexthop);
220 			fatalp("Out of memory\n");
221 			return LDP_E_MEMORY;
222 		}
223 		memcpy(so_ifa, so_oldifa, so_oldifa->sa.sa_len);
224 	} else
225 		so_ifa = NULL;
226 	if (add_route(so_dest, so_pref, so_nexthop, so_ifa, so_tag, FREESO, RTM_CHANGE) != LDP_E_OK)
227 		return LDP_E_ROUTE_ERROR;
228 
229 	debugp("Added %s/%d as label %d to peer %s\n", inet_ntoa(*addr), len,
230 	    label, padd);
231 
232 	return LDP_E_OK;
233 }
234 
235 int
236 mpls_add_ldp_peer(struct ldp_peer * p)
237 {
238 	return LDP_E_OK;
239 }
240 
241 int
242 mpls_delete_ldp_peer(struct ldp_peer * p)
243 {
244 
245 	/* Reput all the routes also to IPv4 */
246 	label_reattach_all_peer_labels(p, LDP_READD_CHANGE);
247 
248 	return LDP_E_OK;
249 }
250 
251 int
252 mpls_start_ldp()
253 {
254 	ldp_peer_init();
255 	label_init();
256 
257 	return LDP_E_OK;
258 }
259