1/* SPDX-License-Identifier: BSD-3-Clause */
2/*
3 * Copyright (c) 1982, 1986, 1993
4 * The Regents of the University of California. All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
14 * 3. Neither the name of the University nor the names of its contributors
15 * may be used to endorse or promote products derived from this software
16 * without specific prior written permission.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
19 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
22 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28 * SUCH DAMAGE.
29 *
30 * @(#)ip.h 8.1 (Berkeley) 6/10/93
31 * ip.h,v 1.3 1994/08/21 05:27:30 paul Exp
32 */
33
34#ifndef IP_H
35#define IP_H
36
37#include <glib.h>
38
39#if G_BYTE_ORDER == G_BIG_ENDIAN
40#undef NTOHL
41#undef NTOHS
42#undef HTONL
43#undef HTONS
44#define NTOHL(d)
45#define NTOHS(d)
46#define HTONL(d)
47#define HTONS(d)
48#else
49#ifndef NTOHL
50#define NTOHL(d) ((d) = ntohl((d)))
51#endif
52#ifndef NTOHS
53#define NTOHS(d) ((d) = ntohs((uint16_t)(d)))
54#endif
55#ifndef HTONL
56#define HTONL(d) ((d) = htonl((d)))
57#endif
58#ifndef HTONS
59#define HTONS(d) ((d) = htons((uint16_t)(d)))
60#endif
61#endif
62
63typedef uint32_t n_long; /* long as received from the net */
64
65/*
66 * Definitions for internet protocol version 4.
67 * Per RFC 791, September 1981.
68 */
69#define IPVERSION 4
70
71/*
72 * Structure of an internet header, naked of options.
73 */
74struct ip {
75#if G_BYTE_ORDER == G_BIG_ENDIAN
76 uint8_t ip_v : 4, /* version */
77 ip_hl : 4; /* header length */
78#else
79 uint8_t ip_hl : 4, /* header length */
80 ip_v : 4; /* version */
81#endif
82 uint8_t ip_tos; /* type of service */
83 uint16_t ip_len; /* total length */
84 uint16_t ip_id; /* identification */
85 uint16_t ip_off; /* fragment offset field */
86#define IP_DF 0x4000 /* don't fragment flag */
87#define IP_MF 0x2000 /* more fragments flag */
88#define IP_OFFMASK 0x1fff /* mask for fragmenting bits */
89 uint8_t ip_ttl; /* time to live */
90 uint8_t ip_p; /* protocol */
91 uint16_t ip_sum; /* checksum */
92 struct in_addr ip_src, ip_dst; /* source and dest address */
93} SLIRP_PACKED;
94
95#define IP_MAXPACKET 65535 /* maximum packet size */
96
97/*
98 * Definitions for IP type of service (ip_tos)
99 */
100#define IPTOS_LOWDELAY 0x10
101#define IPTOS_THROUGHPUT 0x08
102#define IPTOS_RELIABILITY 0x04
103
104/*
105 * Definitions for options.
106 */
107#define IPOPT_COPIED(o) ((o)&0x80)
108#define IPOPT_CLASS(o) ((o)&0x60)
109#define IPOPT_NUMBER(o) ((o)&0x1f)
110
111#define IPOPT_CONTROL 0x00
112#define IPOPT_RESERVED1 0x20
113#define IPOPT_DEBMEAS 0x40
114#define IPOPT_RESERVED2 0x60
115
116#define IPOPT_EOL 0 /* end of option list */
117#define IPOPT_NOP 1 /* no operation */
118
119#define IPOPT_RR 7 /* record packet route */
120#define IPOPT_TS 68 /* timestamp */
121#define IPOPT_SECURITY 130 /* provide s,c,h,tcc */
122#define IPOPT_LSRR 131 /* loose source route */
123#define IPOPT_SATID 136 /* satnet id */
124#define IPOPT_SSRR 137 /* strict source route */
125
126/*
127 * Offsets to fields in options other than EOL and NOP.
128 */
129#define IPOPT_OPTVAL 0 /* option ID */
130#define IPOPT_OLEN 1 /* option length */
131#define IPOPT_OFFSET 2 /* offset within option */
132#define IPOPT_MINOFF 4 /* min value of above */
133
134/*
135 * Time stamp option structure.
136 */
137struct ip_timestamp {
138 uint8_t ipt_code; /* IPOPT_TS */
139 uint8_t ipt_len; /* size of structure (variable) */
140 uint8_t ipt_ptr; /* index of current entry */
141#if G_BYTE_ORDER == G_BIG_ENDIAN
142 uint8_t ipt_oflw : 4, /* overflow counter */
143 ipt_flg : 4; /* flags, see below */
144#else
145 uint8_t ipt_flg : 4, /* flags, see below */
146 ipt_oflw : 4; /* overflow counter */
147#endif
148 union ipt_timestamp {
149 n_long ipt_time[1];
150 struct ipt_ta {
151 struct in_addr ipt_addr;
152 n_long ipt_time;
153 } ipt_ta[1];
154 } ipt_timestamp;
155} SLIRP_PACKED;
156
157/* flag bits for ipt_flg */
158#define IPOPT_TS_TSONLY 0 /* timestamps only */
159#define IPOPT_TS_TSANDADDR 1 /* timestamps and addresses */
160#define IPOPT_TS_PRESPEC 3 /* specified modules only */
161
162/* bits for security (not byte swapped) */
163#define IPOPT_SECUR_UNCLASS 0x0000
164#define IPOPT_SECUR_CONFID 0xf135
165#define IPOPT_SECUR_EFTO 0x789a
166#define IPOPT_SECUR_MMMM 0xbc4d
167#define IPOPT_SECUR_RESTR 0xaf13
168#define IPOPT_SECUR_SECRET 0xd788
169#define IPOPT_SECUR_TOPSECRET 0x6bc5
170
171/*
172 * Internet implementation parameters.
173 */
174#define MAXTTL 255 /* maximum time to live (seconds) */
175#define IPDEFTTL 64 /* default ttl, from RFC 1340 */
176#define IPFRAGTTL 60 /* time to live for frags, slowhz */
177#define IPTTLDEC 1 /* subtracted when forwarding */
178
179#define IP_MSS 576 /* default maximum segment size */
180
181#if GLIB_SIZEOF_VOID_P == 4
182struct mbuf_ptr {
183 struct mbuf *mptr;
184 uint32_t dummy;
185} SLIRP_PACKED;
186#else
187struct mbuf_ptr {
188 struct mbuf *mptr;
189} SLIRP_PACKED;
190#endif
191struct qlink {
192 void *next, *prev;
193};
194
195/*
196 * Overlay for ip header used by other protocols (tcp, udp).
197 */
198struct ipovly {
199 struct mbuf_ptr ih_mbuf; /* backpointer to mbuf */
200 uint8_t ih_x1; /* (unused) */
201 uint8_t ih_pr; /* protocol */
202 uint16_t ih_len; /* protocol length */
203 struct in_addr ih_src; /* source internet address */
204 struct in_addr ih_dst; /* destination internet address */
205} SLIRP_PACKED;
206
207/*
208 * Ip reassembly queue structure. Each fragment
209 * being reassembled is attached to one of these structures.
210 * They are timed out after ipq_ttl drops to 0, and may also
211 * be reclaimed if memory becomes tight.
212 * size 28 bytes
213 */
214struct ipq {
215 struct qlink frag_link; /* to ip headers of fragments */
216 struct qlink ip_link; /* to other reass headers */
217 uint8_t ipq_ttl; /* time for reass q to live */
218 uint8_t ipq_p; /* protocol of this fragment */
219 uint16_t ipq_id; /* sequence id for reassembly */
220 struct in_addr ipq_src, ipq_dst;
221};
222
223/*
224 * Ip header, when holding a fragment.
225 *
226 * Note: ipf_link must be at same offset as frag_link above
227 */
228struct ipasfrag {
229 struct qlink ipf_link;
230 struct ip ipf_ip;
231};
232
233G_STATIC_ASSERT(offsetof(struct ipq, frag_link) ==
234 offsetof(struct ipasfrag, ipf_link));
235
236#define ipf_off ipf_ip.ip_off
237#define ipf_tos ipf_ip.ip_tos
238#define ipf_len ipf_ip.ip_len
239#define ipf_next ipf_link.next
240#define ipf_prev ipf_link.prev
241
242#endif
243