/* SPDX-License-Identifier: GPL-2.0+ WITH Linux-syscall-note */
/*
 *  IPv6 IOAM implementation
 *
 *  Author:
 *  Justin Iurman <justin.iurman@uliege.be>
 */

#ifndef _LINUX_IOAM6_H
#define _LINUX_IOAM6_H

#include <asm/byteorder.h>
#include <linux/types.h>

#define IOAM6_U16_UNAVAILABLE U16_MAX
#define IOAM6_U32_UNAVAILABLE U32_MAX
#define IOAM6_U64_UNAVAILABLE U64_MAX

#define IOAM6_DEFAULT_ID	 (IOAM6_U32_UNAVAILABLE >> 8)
#define IOAM6_DEFAULT_ID_WIDE	 (IOAM6_U64_UNAVAILABLE >> 8)
#define IOAM6_DEFAULT_IF_ID	 IOAM6_U16_UNAVAILABLE
#define IOAM6_DEFAULT_IF_ID_WIDE IOAM6_U32_UNAVAILABLE

/*
 * IPv6 IOAM Option Header
 */
struct ioam6_hdr {
	__u8 opt_type;
	__u8 opt_len;
	__u8 : 8; /* reserved */
#define IOAM6_TYPE_PREALLOC 0
	__u8 type;
} __attribute__((packed));

/*
 * IOAM Trace Header
 */
struct ioam6_trace_hdr {
	__be16 namespace_id;

#if defined(__LITTLE_ENDIAN_BITFIELD)

	__u8 : 1,    /* unused */
		: 1, /* unused */
		overflow : 1, nodelen : 5;

	__u8 remlen : 7, : 1; /* unused */

	union {
		__be32 type_be32;

		struct {
			__u32 bit7 : 1, bit6 : 1, bit5 : 1, bit4 : 1, bit3 : 1,
				bit2 : 1, bit1 : 1, bit0 : 1,
				bit15 : 1, /* unused
					    */
				bit14 : 1, /* unused */
				bit13 : 1, /* unused */
				bit12 : 1, /* unused */
				bit11 : 1, bit10 : 1, bit9 : 1, bit8 : 1,
				bit23 : 1,	      /* reserved */
				bit22 : 1, bit21 : 1, /* unused */
				bit20 : 1,	      /* unused */
				bit19 : 1,	      /* unused */
				bit18 : 1,	      /* unused */
				bit17 : 1,	      /* unused */
				bit16 : 1,	      /* unused */
				: 8;		      /* reserved */
		} type;
	};

#elif defined(__BIG_ENDIAN_BITFIELD)

	__u8 nodelen : 5, overflow : 1, : 1, /* unused */
		: 1;			     /* unused */

	__u8 : 1, /* unused */
		remlen : 7;

	union {
		__be32 type_be32;

		struct {
			__u32 bit0 : 1, bit1 : 1, bit2 : 1, bit3 : 1, bit4 : 1,
				bit5 : 1, bit6 : 1, bit7 : 1, bit8 : 1,
				bit9 : 1, bit10 : 1, bit11 : 1,
				bit12 : 1,	      /* unused
						       */
				bit13 : 1,	      /* unused */
				bit14 : 1,	      /* unused */
				bit15 : 1,	      /* unused */
				bit16 : 1,	      /* unused */
				bit17 : 1,	      /* unused */
				bit18 : 1,	      /* unused */
				bit19 : 1,	      /* unused */
				bit20 : 1,	      /* unused */
				bit21 : 1,	      /* unused */
				bit22 : 1, bit23 : 1, /* reserved */
				: 8;		      /* reserved */
		} type;
	};

#else
#error "Please fix <asm/byteorder.h>"
#endif

#define IOAM6_TRACE_DATA_SIZE_MAX 244
	__u8 data[];
} __attribute__((packed));

#endif /* _LINUX_IOAM6_H */