xref: /openbsd/sys/netinet/ip_gre.c (revision 666d181c)
1 /*      $OpenBSD: ip_gre.c,v 1.89 2025/01/01 13:44:22 bluhm Exp $ */
2 /*	$NetBSD: ip_gre.c,v 1.9 1999/10/25 19:18:11 drochner Exp $ */
3 
4 /*
5  * Copyright (c) 1998 The NetBSD Foundation, Inc.
6  * All rights reserved.
7  *
8  * This code is derived from software contributed to The NetBSD Foundation
9  * by Heiko W.Rupp <hwr@pilhuhn.de>
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions and the following disclaimer.
16  * 2. Redistributions in binary form must reproduce the above copyright
17  *    notice, this list of conditions and the following disclaimer in the
18  *    documentation and/or other materials provided with the distribution.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
21  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
22  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
23  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
24  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
25  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
26  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
27  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
28  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
29  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
30  * POSSIBILITY OF SUCH DAMAGE.
31  */
32 
33 /*
34  * decapsulate tunneled packets and send them on
35  * output half is in net/if_gre.[ch]
36  * This currently handles IPPROTO_GRE, IPPROTO_MOBILE
37  */
38 
39 #include <sys/param.h>
40 #include <sys/systm.h>
41 #include <sys/mbuf.h>
42 #include <sys/protosw.h>
43 #include <sys/socket.h>
44 #include <sys/socketvar.h>
45 #include <sys/sysctl.h>
46 
47 #include <net/if.h>
48 #include <net/if_var.h>
49 #include <net/route.h>
50 
51 #include <netinet/in.h>
52 #include <netinet/ip.h>
53 #include <netinet/ip_gre.h>
54 #include <netinet/ip_var.h>
55 #include <netinet/in_pcb.h>
56 #include <netinet/in_var.h>
57 
58 #ifdef PIPEX
59 #include <net/pipex.h>
60 #endif
61 
62 const struct pr_usrreqs gre_usrreqs = {
63 	.pru_attach	= rip_attach,
64 	.pru_detach	= rip_detach,
65 	.pru_bind	= rip_bind,
66 	.pru_connect	= rip_connect,
67 	.pru_disconnect	= rip_disconnect,
68 	.pru_shutdown	= rip_shutdown,
69 	.pru_send	= gre_send,
70 	.pru_control	= in_control,
71 	.pru_sockaddr	= in_sockaddr,
72 	.pru_peeraddr	= in_peeraddr,
73 };
74 
75 int
76 gre_send(struct socket *so, struct mbuf *m, struct mbuf *nam,
77     struct mbuf *control)
78 {
79 #ifdef PIPEX
80 	struct inpcb *inp = sotoinpcb(so);
81 
82 	if (inp->inp_pipex) {
83 		struct sockaddr_in *sin4;
84 		const struct in_addr *ina_dst;
85 
86 		ina_dst = NULL;
87 		if ((so->so_state & SS_ISCONNECTED) != 0)
88 			ina_dst = &inp->inp_laddr;
89 		else if (nam) {
90 			if (in_nam2sin(nam, &sin4) == 0)
91 				ina_dst = &sin4->sin_addr;
92 		}
93 		if (ina_dst != NULL) {
94 			struct pipex_session *session;
95 
96 			session = pipex_pptp_userland_lookup_session_ipv4(m,
97 			    *ina_dst);
98 
99 			if(session != NULL) {
100 				m = pipex_pptp_userland_output(m, session);
101 				pipex_rele_session(session);
102 			}
103 		}
104 
105 		if (m == NULL) {
106 			m_freem(control);
107 			return (ENOMEM);
108 		}
109 	}
110 #endif
111 	return rip_send(so, m, nam, control);
112 }
113