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_TCP_H
32 #define _LINUXKPI_LINUX_TCP_H
33
34 #include <sys/types.h>
35 #include <linux/skbuff.h>
36
37 /* (u) unconfirmed structure field names; using FreeBSD's meanwhile. */
38 struct tcphdr {
39 uint16_t source; /* (u) */
40 uint16_t dest; /* (u) */
41 uint32_t th_seq; /* (u) */
42 uint32_t th_ack; /* (u) */
43 #if BYTE_ORDER == LITTLE_ENDIAN
44 uint8_t th_x2:4, doff:4;
45 #elif BYTE_ORDER == BIG_ENDIAN
46 uint8_t doff:4, th_x2:4;
47 #endif
48 uint8_t th_flags; /* (u) */
49 uint16_t th_win; /* (u) */
50 uint16_t check;
51 uint16_t th_urg; /* (u) */
52 };
53
54 static __inline struct tcphdr *
tcp_hdr(struct sk_buff * skb)55 tcp_hdr(struct sk_buff *skb)
56 {
57
58 return (struct tcphdr *)skb_transport_header(skb);
59 }
60
61 static __inline uint32_t
tcp_hdrlen(struct sk_buff * skb)62 tcp_hdrlen(struct sk_buff *skb)
63 {
64 struct tcphdr *th;
65
66 th = tcp_hdr(skb);
67 return (4 * th->doff);
68 }
69
70 #endif /* _LINUXKPI_LINUX_TCP_H */
71