1 /* SPDX-License-Identifier: GPL-2.0+ WITH Linux-syscall-note */
2 /*
3  * INET		An implementation of the TCP/IP protocol suite for the LINUX
4  *		operating system.  INET is implemented using the  BSD Socket
5  *		interface as the means of communication with the user level.
6  *
7  *		Definitions for the IP protocol.
8  *
9  * Version:	@(#)ip.h	1.0.2	04/28/93
10  *
11  * Authors:	Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
12  *
13  *		This program is free software; you can redistribute it and/or
14  *		modify it under the terms of the GNU General Public License
15  *		as published by the Free Software Foundation; either version
16  *		2 of the License, or (at your option) any later version.
17  */
18 #ifndef _LINUX_IP_H
19 #define _LINUX_IP_H
20 #include <linux/types.h>
21 #include <asm/byteorder.h>
22 
23 #define IPTOS_TOS_MASK		0x1E
24 #define IPTOS_TOS(tos)		((tos)&IPTOS_TOS_MASK)
25 #define	IPTOS_LOWDELAY		0x10
26 #define	IPTOS_THROUGHPUT	0x08
27 #define	IPTOS_RELIABILITY	0x04
28 #define	IPTOS_MINCOST		0x02
29 
30 #define IPTOS_PREC_MASK		0xE0
31 #define IPTOS_PREC(tos)		((tos)&IPTOS_PREC_MASK)
32 #define IPTOS_PREC_NETCONTROL           0xe0
33 #define IPTOS_PREC_INTERNETCONTROL      0xc0
34 #define IPTOS_PREC_CRITIC_ECP           0xa0
35 #define IPTOS_PREC_FLASHOVERRIDE        0x80
36 #define IPTOS_PREC_FLASH                0x60
37 #define IPTOS_PREC_IMMEDIATE            0x40
38 #define IPTOS_PREC_PRIORITY             0x20
39 #define IPTOS_PREC_ROUTINE              0x00
40 
41 
42 /* IP options */
43 #define IPOPT_COPY		0x80
44 #define IPOPT_CLASS_MASK	0x60
45 #define IPOPT_NUMBER_MASK	0x1f
46 
47 #define	IPOPT_COPIED(o)		((o)&IPOPT_COPY)
48 #define	IPOPT_CLASS(o)		((o)&IPOPT_CLASS_MASK)
49 #define	IPOPT_NUMBER(o)		((o)&IPOPT_NUMBER_MASK)
50 
51 #define	IPOPT_CONTROL		0x00
52 #define	IPOPT_RESERVED1		0x20
53 #define	IPOPT_MEASUREMENT	0x40
54 #define	IPOPT_RESERVED2		0x60
55 
56 #define IPOPT_END	(0 |IPOPT_CONTROL)
57 #define IPOPT_NOOP	(1 |IPOPT_CONTROL)
58 #define IPOPT_SEC	(2 |IPOPT_CONTROL|IPOPT_COPY)
59 #define IPOPT_LSRR	(3 |IPOPT_CONTROL|IPOPT_COPY)
60 #define IPOPT_TIMESTAMP	(4 |IPOPT_MEASUREMENT)
61 #define IPOPT_CIPSO	(6 |IPOPT_CONTROL|IPOPT_COPY)
62 #define IPOPT_RR	(7 |IPOPT_CONTROL)
63 #define IPOPT_SID	(8 |IPOPT_CONTROL|IPOPT_COPY)
64 #define IPOPT_SSRR	(9 |IPOPT_CONTROL|IPOPT_COPY)
65 #define IPOPT_RA	(20|IPOPT_CONTROL|IPOPT_COPY)
66 
67 #define IPVERSION	4
68 #define MAXTTL		255
69 #define IPDEFTTL	64
70 
71 #define IPOPT_OPTVAL 0
72 #define IPOPT_OLEN   1
73 #define IPOPT_OFFSET 2
74 #define IPOPT_MINOFF 4
75 #define MAX_IPOPTLEN 40
76 #define IPOPT_NOP IPOPT_NOOP
77 #define IPOPT_EOL IPOPT_END
78 #define IPOPT_TS  IPOPT_TIMESTAMP
79 
80 #define	IPOPT_TS_TSONLY		0		/* timestamps only */
81 #define	IPOPT_TS_TSANDADDR	1		/* timestamps and addresses */
82 #define	IPOPT_TS_PRESPEC	3		/* specified modules only */
83 
84 #define IPV4_BEET_PHMAXLEN 8
85 
86 struct iphdr {
87 #if defined(__LITTLE_ENDIAN_BITFIELD)
88 	__u8	ihl:4,
89 		version:4;
90 #elif defined (__BIG_ENDIAN_BITFIELD)
91 	__u8	version:4,
92   		ihl:4;
93 #else
94 #error	"Please fix <asm/byteorder.h>"
95 #endif
96 	__u8	tos;
97 	__be16	tot_len;
98 	__be16	id;
99 	__be16	frag_off;
100 	__u8	ttl;
101 	__u8	protocol;
102 	__sum16	check;
103 	__be32	saddr;
104 	__be32	daddr;
105 	/*The options start here. */
106 };
107 
108 
109 struct ip_auth_hdr {
110 	__u8  nexthdr;
111 	__u8  hdrlen;		/* This one is measured in 32 bit units! */
112 	__be16 reserved;
113 	__be32 spi;
114 	__be32 seq_no;		/* Sequence number */
115 	__u8  auth_data[0];	/* Variable len but >=4. Mind the 64 bit alignment! */
116 };
117 
118 struct ip_esp_hdr {
119 	__be32 spi;
120 	__be32 seq_no;		/* Sequence number */
121 	__u8  enc_data[0];	/* Variable len but >=8. Mind the 64 bit alignment! */
122 };
123 
124 struct ip_comp_hdr {
125 	__u8 nexthdr;
126 	__u8 flags;
127 	__be16 cpi;
128 };
129 
130 struct ip_beet_phdr {
131 	__u8 nexthdr;
132 	__u8 hdrlen;
133 	__u8 padlen;
134 	__u8 reserved;
135 };
136 
137 /* index values for the variables in ipv4_devconf */
138 enum
139 {
140 	IPV4_DEVCONF_FORWARDING=1,
141 	IPV4_DEVCONF_MC_FORWARDING,
142 	IPV4_DEVCONF_PROXY_ARP,
143 	IPV4_DEVCONF_ACCEPT_REDIRECTS,
144 	IPV4_DEVCONF_SECURE_REDIRECTS,
145 	IPV4_DEVCONF_SEND_REDIRECTS,
146 	IPV4_DEVCONF_SHARED_MEDIA,
147 	IPV4_DEVCONF_RP_FILTER,
148 	IPV4_DEVCONF_ACCEPT_SOURCE_ROUTE,
149 	IPV4_DEVCONF_BOOTP_RELAY,
150 	IPV4_DEVCONF_LOG_MARTIANS,
151 	IPV4_DEVCONF_TAG,
152 	IPV4_DEVCONF_ARPFILTER,
153 	IPV4_DEVCONF_MEDIUM_ID,
154 	IPV4_DEVCONF_NOXFRM,
155 	IPV4_DEVCONF_NOPOLICY,
156 	IPV4_DEVCONF_FORCE_IGMP_VERSION,
157 	IPV4_DEVCONF_ARP_ANNOUNCE,
158 	IPV4_DEVCONF_ARP_IGNORE,
159 	IPV4_DEVCONF_PROMOTE_SECONDARIES,
160 	IPV4_DEVCONF_ARP_ACCEPT,
161 	IPV4_DEVCONF_ARP_NOTIFY,
162 	IPV4_DEVCONF_ACCEPT_LOCAL,
163 	IPV4_DEVCONF_SRC_VMARK,
164 	IPV4_DEVCONF_PROXY_ARP_PVLAN,
165 	IPV4_DEVCONF_ROUTE_LOCALNET,
166 	IPV4_DEVCONF_IGMPV2_UNSOLICITED_REPORT_INTERVAL,
167 	IPV4_DEVCONF_IGMPV3_UNSOLICITED_REPORT_INTERVAL,
168 	IPV4_DEVCONF_IGNORE_ROUTES_WITH_LINKDOWN,
169 	IPV4_DEVCONF_DROP_UNICAST_IN_L2_MULTICAST,
170 	IPV4_DEVCONF_DROP_GRATUITOUS_ARP,
171 	__IPV4_DEVCONF_MAX
172 };
173 
174 #define IPV4_DEVCONF_MAX (__IPV4_DEVCONF_MAX - 1)
175 
176 #endif /* _LINUX_IP_H */
177