xref: /netbsd-src/usr.sbin/ldpd/mpls_interface.c (revision a536ee5124e62c9a0051a252f7833dc8f50f44c9)
1 /* $NetBSD: mpls_interface.c,v 1.6 2011/06/14 11:28:51 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 extern int no_default_route;
54 
55 int
56 mpls_add_label(struct ldp_peer * p, struct rt_msg * inh_rg,
57     struct in_addr * addr, int len, int label, int rlookup)
58 {
59 	char            padd[20];
60 	int             kount = 0, rv;
61 	union sockunion *so_dest, *so_pref = NULL, *so_gate, *so_nexthop, *so_tag,
62 		*so_oldifa = NULL, *so_ifa;
63 	struct rt_msg   rg;
64 	struct rt_msg	*rgp = &rg;
65 	struct label	*lab;
66 
67 	strlcpy(padd, inet_ntoa(p->address), 20);
68 	debugp("Trying to add %s/%d as label %d to peer %s\n", inet_ntoa(*addr),
69 		len, label, padd);
70 
71 	/* Check if we should accept default route */
72 	if (!len && no_default_route != 0)
73 		return LDP_E_BAD_AF;
74 
75 	/* Is there a label mapping for this ? */
76 	if (ldp_peer_get_lm(p, addr, len) == NULL)
77 		return LDP_E_NOENT;
78 
79 	if (!inh_rg || (inh_rg->m_rtm.rtm_addrs & RTA_IFA) == 0) {
80 		/*
81 		 * XXX: Check if we have a route for that.
82 		 * Why the hell isn't kernel inserting the route immediatly ?
83 		 * let's loop until we have it..
84 		 */
85 
86 		if ((so_dest = make_inet_union(inet_ntoa(*addr))) == NULL)
87 			return LDP_E_MEMORY;
88 		if (len != 32 && (so_pref = from_cidr_to_union(len)) == NULL) {
89 			free(so_dest);
90 			return LDP_E_MEMORY;
91 		}
92 		do {
93 			if (kount == rlookup) {
94 				debugp("No route for this prefix\n");
95 				return LDP_E_NO_SUCH_ROUTE;
96 			}
97 			if (kount > 0)
98 				debugp("Route test hit: %d\n", kount);
99 			kount++;
100 			/* Last time give it a higher chance */
101 			if (kount == rlookup)
102 				usleep(5000);
103 
104 			rv = get_route(rgp, so_dest, so_pref, 1);
105 			if (rv != LDP_E_OK && len == 32)
106 				/* Host maybe ? */
107 				rv = get_route(rgp, so_dest, NULL, 1);
108 		} while (rv != LDP_E_OK);
109 
110 		free(so_dest);
111 		if (so_pref)
112 			free(so_pref);
113 
114 	} else
115 		rgp = inh_rg;
116 
117 	/* Check if it's an IPv4 route */
118 
119 	so_gate = (union sockunion *) rgp->m_space;
120 	so_gate = (union sockunion *)((char*)so_gate +
121 	    RT_ROUNDUP(so_gate->sa.sa_len));
122 	if (rgp->m_rtm.rtm_addrs & RTA_IFA) {
123 		int li = 1;
124 		so_oldifa = so_gate;
125 		if (rgp->m_rtm.rtm_addrs & RTA_NETMASK)
126 			li++;
127 		if (rgp->m_rtm.rtm_addrs & RTA_GENMASK)
128 			li++;
129 		if (rgp->m_rtm.rtm_addrs & RTA_IFP)
130 			li++;
131 		for (int i = 0; i < li; i++)
132 			so_oldifa = (union sockunion *)((char*)so_oldifa +
133 			    RT_ROUNDUP(so_oldifa->sa.sa_len));
134 	}
135 
136 	if (so_gate->sa.sa_family != AF_INET) {
137 		debugp("Failed at family check - only INET supoprted for now\n");
138 		return LDP_E_BAD_AF;
139 	}
140 
141 	/* Check if the address is bounded to the peer */
142 	if (check_ifaddr(p, &so_gate->sin.sin_addr) == NULL) {
143 		debugp("Failed at next-hop check\n");
144 		return LDP_E_ROUTE_ERROR;
145 	}
146 
147 	/* CHECK IF WE HAVE A BINDING FOR THAT */
148 	lab = label_get_by_prefix(addr, len);
149 
150 	/* We should have a label because we have a route */
151 	assert (lab);
152 
153 	if (lab->binding == MPLS_LABEL_IMPLNULL) {
154 		change_local_label(lab, get_free_local_label());
155 		if (!lab->binding) {
156 			fatalp("No more free labels !!!\n");
157 			return LDP_E_TOO_MANY_LABELS;
158 		}
159 	}
160 
161 	warnp("[mpls_add_label] Adding %s/%d as local binding %d, label %d"
162 	    " to peer %s\n",
163 		inet_ntoa(*addr), len, lab->binding, label, padd);
164 
165 	/* Modify existing label */
166 	lab->label = label;
167 	lab->p = p;
168 
169 	/* Add switching route */
170 	so_dest = make_mpls_union(lab->binding);
171 	so_nexthop = malloc(sizeof(*so_nexthop));
172 	if (!so_nexthop) {
173 		free(so_dest);
174 		fatalp("Out of memory\n");
175 		return LDP_E_MEMORY;
176 	}
177 	memcpy(so_nexthop, so_gate, so_gate->sa.sa_len);
178 	if ((so_tag = make_mpls_union(label)) == NULL) {
179 		free(so_dest);
180 		free(so_nexthop);
181 		fatalp("Out of memory\n");
182 		return LDP_E_MEMORY;
183 	}
184 	if (add_route(so_dest, NULL, so_nexthop, NULL, so_tag, FREESO, RTM_ADD) != LDP_E_OK)
185 		return LDP_E_ROUTE_ERROR;
186 
187 	/* Now, let's add tag to IPv4 route and point it to mpls interface */
188 	if ((so_dest = make_inet_union(inet_ntoa(*addr))) == NULL) {
189 		fatalp("Out of memory\n");
190 		return LDP_E_MEMORY;
191 	}
192 
193 	/* if prefixlen == 32 check if it's inserted as host
194  	* and treat it as host. It may also be set as /32 prefix
195  	* (thanks mlelstv for heads-up about this)
196  	*/
197 	if ((len == 32) && (rgp->m_rtm.rtm_flags & RTF_HOST))
198 		so_pref = NULL;
199 	else if ((so_pref = from_cidr_to_union(len)) == NULL) {
200 		free(so_dest);
201 		fatalp("Out of memory\n");
202 		return LDP_E_MEMORY;
203 	}
204 
205 	/* Add tag to route */
206 	so_nexthop = malloc(sizeof(*so_nexthop));
207 	if (!so_nexthop) {
208 		free(so_dest);
209 		if (so_pref != NULL)
210 			free(so_pref);
211 		fatalp("Out of memory\n");
212 		return LDP_E_MEMORY;
213 	}
214 	memcpy(so_nexthop, so_gate, so_gate->sa.sa_len);
215 	so_tag = make_mpls_union(label);
216 	if (so_oldifa != NULL) {
217 		so_ifa = malloc(sizeof(*so_ifa));
218 		if (so_ifa == NULL) {
219 			free(so_dest);
220 			if (so_pref != NULL)
221 				free(so_pref);
222 			free(so_tag);
223 			free(so_nexthop);
224 			fatalp("Out of memory\n");
225 			return LDP_E_MEMORY;
226 		}
227 		memcpy(so_ifa, so_oldifa, so_oldifa->sa.sa_len);
228 	} else
229 		so_ifa = NULL;
230 	if (add_route(so_dest, so_pref, so_nexthop, so_ifa, so_tag, FREESO, RTM_CHANGE) != LDP_E_OK)
231 		return LDP_E_ROUTE_ERROR;
232 
233 	debugp("Added %s/%d as label %d to peer %s\n", inet_ntoa(*addr), len,
234 	    label, padd);
235 
236 	return LDP_E_OK;
237 }
238 
239 int
240 mpls_add_ldp_peer(struct ldp_peer * p)
241 {
242 	return LDP_E_OK;
243 }
244 
245 int
246 mpls_delete_ldp_peer(struct ldp_peer * p)
247 {
248 
249 	/* Reput all the routes also to IPv4 */
250 	label_reattach_all_peer_labels(p, LDP_READD_CHANGE);
251 
252 	return LDP_E_OK;
253 }
254 
255 int
256 mpls_start_ldp()
257 {
258 	ldp_peer_init();
259 	label_init();
260 
261 	return LDP_E_OK;
262 }
263