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/*
* Copyright 2013 Google Inc.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
* 02110-1301, USA.
*/
/*
* Author: ncardwell@google.com (Neal Cardwell)
*
* Our own IPv4 header declarations, so we have something that's
* portable and somewhat more readable than a typical system header
* file.
*/
#ifndef __IP_HEADERS_H__
#define __IP_HEADERS_H__
#include "types.h"
struct ipv4 {
#if __BYTE_ORDER == __LITTLE_ENDIAN
__u8 ihl:4,
version:4;
#elif __BYTE_ORDER == __BIG_ENDIAN
__u8 version:4,
ihl:4;
#else
# error "Please fix endianness defines"
#endif
__u8 tos;
__be16 tot_len;
__be16 id;
__be16 frag_off;
__u8 ttl;
__u8 protocol;
__sum16 check;
struct in_addr src_ip;
struct in_addr dst_ip;
};
/* ----------------------- IP socket option values -------------------- */
/* Oddly enough, Linux distributions are typically missing even some
* of the older and more common IP socket options, such as IP_MTU.
*/
#ifdef linux
#define IP_TOS 1
#define IP_TTL 2
#define IP_HDRINCL 3
#define IP_OPTIONS 4
#define IP_ROUTER_ALERT 5
#define IP_RECVOPTS 6
#define IP_RETOPTS 7
#define IP_PKTINFO 8
#define IP_PKTOPTIONS 9
#define IP_MTU_DISCOVER 10
#define IP_RECVERR 11
#define IP_RECVTTL 12
#define IP_RECVTOS 13
#define IP_MTU 14
#define IP_FREEBIND 15
#define IP_IPSEC_POLICY 16
#define IP_XFRM_POLICY 17
#define IP_PASSSEC 18
#define IP_TRANSPARENT 19
#endif /* linux */
/* ECN: RFC 3168: http://tools.ietf.org/html/rfc3168 */
#define IP_ECN_MASK 3
#define IP_ECN_NONE 0
#define IP_ECN_ECT1 1
#define IP_ECN_ECT0 2
#define IP_ECN_CE 3
static inline u8 ipv4_tos_byte(const struct ipv4 *ipv4)
{
return ipv4->tos;
}
static inline u8 ipv4_ttl_byte(const struct ipv4 *ipv4)
{
return ipv4->ttl;
}
static inline int ipv4_header_len(const struct ipv4 *ipv4)
{
return ipv4->ihl * sizeof(u32);
}
/* IP fragmentation bit flags */
#define IP_RF 0x8000 /* reserved fragment flag */
#define IP_DF 0x4000 /* don't fragment flag */
#define IP_MF 0x2000 /* more fragments flag */
#define IP_OFFMASK 0x1FFF /* mask for fragmenting bits */
#endif /* __IP_HEADERS_H__ */
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