xref: /freebsd/sys/compat/linuxkpi/common/include/linux/ip.h (revision 5f4c09dd85bff675e0ca63c55ea3c517e0fddfcc)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2020-2021 The FreeBSD Foundation
5  *
6  * This software was developed by Björn Zeeb under sponsorship from
7  * the FreeBSD Foundation.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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 
31 #ifndef	_LINUXKPI_LINUX_IP_H
32 #define	_LINUXKPI_LINUX_IP_H
33 
34 #include <sys/types.h>
35 
36 #include <netinet/in.h>
37 #include <netinet/ip.h>
38 #include <machine/in_cksum.h>
39 
40 #include <linux/skbuff.h>
41 
42 /* (u) unconfirmed structure field names; using FreeBSD's meanwhile. */
43 struct iphdr {
44 	uint8_t		ip_hl:4, ip_ver:4;	/* (u) */
45 	uint8_t		ip_tos;			/* (u) */
46 	uint16_t	ip_len;			/* (u) */
47 	uint16_t	id;
48 	uint16_t	ip_off;			/* (u) */
49 	uint8_t		ip_ttl;			/* (u) */
50 	uint8_t		protocol;
51 	uint16_t	check;
52 	uint32_t	saddr;
53 	uint32_t	daddr;
54 };
55 
56 static __inline struct iphdr *
57 ip_hdr(struct sk_buff *skb)
58 {
59 
60 	return (struct iphdr *)skb_network_header(skb);
61 }
62 
63 static __inline void
64 ip_send_check(struct iphdr *iph)
65 {
66 
67 	/* Clear the checksum before computing! */
68 	iph->check = 0;
69 	/* An IPv4 header is the same everywhere even if names differ. */
70 	iph->check = in_cksum_hdr((const void *)iph);
71 }
72 
73 #endif	/* _LINUXKPI_LINUX_IP_H */
74