xref: /openbsd-src/lib/libc/net/rthdr.c (revision 8500990981f885cbe5e6a4958549cacc238b5ae6)
1 /*	$OpenBSD: rthdr.c,v 1.6 2003/06/11 02:54:02 itojun Exp $	*/
2 
3 /*
4  * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. Neither the name of the project nor the names of its contributors
16  *    may be used to endorse or promote products derived from this software
17  *    without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  */
31 
32 #include <sys/param.h>
33 #include <sys/types.h>
34 #include <sys/socket.h>
35 
36 #include <netinet/in.h>
37 #include <netinet/ip6.h>
38 
39 #include <string.h>
40 #include <stdio.h>
41 
42 size_t
43 inet6_rthdr_space(type, seg)
44 	int type, seg;
45 {
46 	switch (type) {
47 	case IPV6_RTHDR_TYPE_0:
48 		if (seg < 1 || seg > 23)
49 			return (0);
50 		return (CMSG_SPACE(sizeof(struct in6_addr) * seg +
51 		    sizeof(struct ip6_rthdr0)));
52 	default:
53 		return (0);
54 	}
55 }
56 
57 struct cmsghdr *
58 inet6_rthdr_init(bp, type)
59 	void *bp;
60 	int type;
61 {
62 	struct cmsghdr *ch = (struct cmsghdr *)bp;
63 	struct ip6_rthdr *rthdr;
64 
65 	rthdr = (struct ip6_rthdr *)CMSG_DATA(ch);
66 
67 	ch->cmsg_level = IPPROTO_IPV6;
68 	ch->cmsg_type = IPV6_RTHDR;
69 
70 	switch (type) {
71 	case IPV6_RTHDR_TYPE_0:
72 		ch->cmsg_len = CMSG_LEN(sizeof(struct ip6_rthdr0));
73 		bzero(rthdr, sizeof(struct ip6_rthdr0));
74 		rthdr->ip6r_type = IPV6_RTHDR_TYPE_0;
75 		return (ch);
76 	default:
77 		return (NULL);
78 	}
79 }
80 
81 int
82 inet6_rthdr_add(cmsg, addr, flags)
83 	struct cmsghdr *cmsg;
84 	const struct in6_addr *addr;
85 	u_int flags;
86 {
87 	struct ip6_rthdr *rthdr;
88 
89 	rthdr = (struct ip6_rthdr *)CMSG_DATA(cmsg);
90 
91 	switch (rthdr->ip6r_type) {
92 	case IPV6_RTHDR_TYPE_0:
93 	{
94 		struct ip6_rthdr0 *rt0 = (struct ip6_rthdr0 *)rthdr;
95 		if (flags != IPV6_RTHDR_LOOSE)
96 			return (-1);
97 		if (rt0->ip6r0_segleft == 23)
98 			return (-1);
99 		rt0->ip6r0_segleft++;
100 		bcopy(addr, (caddr_t)rt0 + ((rt0->ip6r0_len + 1) << 3),
101 		    sizeof(struct in6_addr));
102 		rt0->ip6r0_len += sizeof(struct in6_addr) >> 3;
103 		cmsg->cmsg_len = CMSG_LEN((rt0->ip6r0_len + 1) << 3);
104 		break;
105 	}
106 	default:
107 		return (-1);
108 	}
109 
110 	return (0);
111 }
112 
113 int
114 inet6_rthdr_lasthop(cmsg, flags)
115 	struct cmsghdr *cmsg;
116 	unsigned int flags;
117 {
118 	struct ip6_rthdr *rthdr;
119 
120 	rthdr = (struct ip6_rthdr *)CMSG_DATA(cmsg);
121 
122 	switch (rthdr->ip6r_type) {
123 	case IPV6_RTHDR_TYPE_0:
124 	{
125 		struct ip6_rthdr0 *rt0 = (struct ip6_rthdr0 *)rthdr;
126 		if (flags != IPV6_RTHDR_LOOSE)
127 			return (-1);
128 		if (rt0->ip6r0_segleft > 23)
129 			return (-1);
130 		break;
131 	}
132 	default:
133 		return (-1);
134 	}
135 
136 	return (0);
137 }
138 
139 #if 0
140 int
141 inet6_rthdr_reverse(in, out)
142 	const struct cmsghdr *in;
143 	struct cmsghdr *out;
144 {
145 
146 	return (-1);
147 }
148 #endif
149 
150 int
151 inet6_rthdr_segments(cmsg)
152 	const struct cmsghdr *cmsg;
153 {
154 	struct ip6_rthdr *rthdr;
155 
156 	rthdr = (struct ip6_rthdr *)CMSG_DATA(cmsg);
157 
158 	switch (rthdr->ip6r_type) {
159 	case IPV6_RTHDR_TYPE_0:
160 	{
161 		struct ip6_rthdr0 *rt0 = (struct ip6_rthdr0 *)rthdr;
162 
163 		if (rt0->ip6r0_len % 2 || 46 < rt0->ip6r0_len)
164 			return (-1);
165 
166 		return (rt0->ip6r0_len * 8) / sizeof(struct in6_addr);
167 	}
168 
169 	default:
170 		return (-1);
171 	}
172 }
173 
174 struct in6_addr *
175 inet6_rthdr_getaddr(cmsg, index)
176 	struct cmsghdr *cmsg;
177 	int index;
178 {
179 	struct ip6_rthdr *rthdr;
180 
181 	rthdr = (struct ip6_rthdr *)CMSG_DATA(cmsg);
182 
183 	switch (rthdr->ip6r_type) {
184 	case IPV6_RTHDR_TYPE_0:
185 	{
186 		struct ip6_rthdr0 *rt0 = (struct ip6_rthdr0 *)rthdr;
187 		int naddr;
188 
189 		if (rt0->ip6r0_len % 2 || 46 < rt0->ip6r0_len)
190 			return NULL;
191 		naddr = (rt0->ip6r0_len * 8) / sizeof(struct in6_addr);
192 		if (index <= 0 || naddr < index)
193 			return NULL;
194 		return ((struct in6_addr *)(rt0 + 1)) + index;
195 	}
196 
197 	default:
198 		return NULL;
199 	}
200 }
201 
202 int
203 inet6_rthdr_getflags(cmsg, index)
204 	const struct cmsghdr *cmsg;
205 	int index;
206 {
207 	struct ip6_rthdr *rthdr;
208 
209 	rthdr = (struct ip6_rthdr *)CMSG_DATA(cmsg);
210 
211 	switch (rthdr->ip6r_type) {
212 	case IPV6_RTHDR_TYPE_0:
213 	{
214 		struct ip6_rthdr0 *rt0 = (struct ip6_rthdr0 *)rthdr;
215 		int naddr;
216 
217 		if (rt0->ip6r0_len % 2 || 46 < rt0->ip6r0_len)
218 			return (-1);
219 		naddr = (rt0->ip6r0_len * 8) / sizeof(struct in6_addr);
220 		if (index < 0 || naddr < index)
221 			return (-1);
222 		return IPV6_RTHDR_LOOSE;
223 	}
224 
225 	default:
226 		return (-1);
227 	}
228 }
229