summaryrefslogtreecommitdiff
path: root/sys/netmpls/mpls_output.c
blob: 3139918be0dba8ae8eb9975a0d6edf1f8f6f9c42 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
/* $Id: mpls_output.c,v 1.1 2008/10/28 01:16:14 michele Exp $ */

/*
 * Copyright (c) 2008 Claudio Jeker <claudio@openbsd.org>
 * Copyright (c) 2008 Michele Marchetto <michele@openbsd.org>
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

#include <sys/param.h>
#include <sys/mbuf.h>
#include <sys/systm.h>
#include <sys/socket.h>

#include <net/if.h>
#include <net/route.h>

#include <netmpls/mpls.h>

extern int	mpls_inkloop;

#ifdef MPLS_DEBUG
#define MPLS_LABEL_GET(l)	((ntohl((l) & MPLS_LABEL_MASK)) >> MPLS_LABEL_OFFSET)
#endif

void
mpls_output(struct mbuf *m)
{
	struct ifnet		*ifp = m->m_pkthdr.rcvif;
	struct sockaddr_mpls	*smpls;
	struct sockaddr_mpls	 sa_mpls;
	struct shim_hdr		*shim;
	struct rtentry		*rt = NULL;
	u_int32_t		 ttl;
	int			 i;

	if (!mpls_enable) {
		m_freem(m);
		return;
	}

	/* reset broadcast and multicast flags, this is a P2P tunnel */
	m->m_flags &= ~(M_BCAST | M_MCAST);

	if (m->m_len < sizeof(*shim))
		if ((m = m_pullup(m, sizeof(*shim))) == NULL)
			return;

	shim = mtod(m, struct shim_hdr *);

	/* extract TTL */
	ttl = shim->shim_label & MPLS_TTL_MASK;

	for (i = 0; i < mpls_inkloop; i++) {
		bzero(&sa_mpls, sizeof(sa_mpls));
		smpls = &sa_mpls;
		smpls->smpls_family = AF_MPLS;
		smpls->smpls_len = sizeof(*smpls);
		smpls->smpls_in_ifindex = ifp->if_index;
		smpls->smpls_in_label = shim->shim_label & MPLS_LABEL_MASK;

#ifdef MPLS_DEBUG
		printf("smpls af %d len %d in_label %d in_ifindex %d\n",
		    smpls->smpls_family, smpls->smpls_len,
		    MPLS_LABEL_GET(smpls->smpls_in_label),
		    smpls->smpls_in_ifindex);
#endif

		rt = rtalloc1(smplstosa(smpls), 1, 0);

		if (rt == NULL) {
			/* no entry for this label */
#ifdef MPLS_DEBUG
			printf("MPLS_DEBUG: label not found\n");
#endif
			m_freem(m);
			goto done;
		}

		rt->rt_use++;
		smpls = satosmpls(rt_key(rt));

#ifdef MPLS_DEBUG
		printf("route af %d len %d in_label %d in_ifindex %d\n",
		    smpls->smpls_family, smpls->smpls_len,
		    MPLS_LABEL_GET(smpls->smpls_in_label),
		    smpls->smpls_in_ifindex);
		printf("\top %d out_label %d out_ifindex %d\n",
		    smpls->smpls_operation,
		    MPLS_LABEL_GET(smpls->smpls_out_label),
		    smpls->smpls_out_ifindex);
#endif

		switch (smpls->smpls_operation) {
		case MPLS_OP_POP:
			if (MPLS_BOS_ISSET(shim->shim_label)) {
				/* drop to avoid loops */
				m_freem(m);
				goto done;
			}

			m = mpls_shim_pop(m);
			break;
		case MPLS_OP_PUSH:
			m = mpls_shim_push(m, smpls);
			break;
		case MPLS_OP_SWAP:
			m = mpls_shim_swap(m, smpls);
			break;
		default:
			m_freem(m);
			goto done;
		}

		if (m == NULL)
			goto done;

		/* refetch label */
		shim = mtod(m, struct shim_hdr *);
		ifp = rt->rt_ifp;

		if (smpls->smpls_out_ifindex)
			break;

		RTFREE(rt);
		rt = NULL;
	}

	/* write back TTL */
	shim->shim_label = (shim->shim_label & ~MPLS_TTL_MASK) | ttl;

#ifdef MPLS_DEBUG
	printf("MPLS: sending on %s outlabel %x dst af %d in %d out %d\n",
	    ifp->if_xname, ntohl(shim->shim_label), smpls->smpls_family,
	    MPLS_LABEL_GET(smpls->smpls_in_label),
	    MPLS_LABEL_GET(smpls->smpls_out_label));
#endif

	(*ifp->if_output)(ifp, m, smplstosa(smpls), rt);
done:
	if (rt)
		RTFREE(rt);
}