[mirror_ubuntu-jammy-kernel.git] / include / net / erspan.h

#ifndef __LINUX_ERSPAN_H
#define __LINUX_ERSPAN_H

/*
 * GRE header for ERSPAN type I encapsulation (4 octets [34:37])
 *      0                   1                   2                   3
 *      0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
 *     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *     |0|0|0|0|0|00000|000000000|00000|    Protocol Type for ERSPAN   |
 *     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *
 *  The Type I ERSPAN frame format is based on the barebones IP + GRE
 *  encapsulation (as described above) on top of the raw mirrored frame.
 *  There is no extra ERSPAN header.
 *
 *
 * GRE header for ERSPAN type II and II encapsulation (8 octets [34:41])
 *       0                   1                   2                   3
 *      0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
 *     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *     |0|0|0|1|0|00000|000000000|00000|    Protocol Type for ERSPAN   |
 *     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *     |      Sequence Number (increments per packet per session)      |
 *     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *
 *  Note that in the above GRE header [RFC1701] out of the C, R, K, S,
 *  s, Recur, Flags, Version fields only S (bit 03) is set to 1. The
 *  other fields are set to zero, so only a sequence number follows.
 *
 *  ERSPAN Version 1 (Type II) header (8 octets [42:49])
 *  0                   1                   2                   3
 *  0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 * |  Ver  |          VLAN         | COS | En|T|    Session ID     |
 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 * |      Reserved         |                  Index                |
 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *
 *
 *  ERSPAN Version 2 (Type III) header (12 octets [42:49])
 *  0                   1                   2                   3
 *  0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 * |  Ver  |          VLAN         | COS |BSO|T|     Session ID    |
 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 * |                          Timestamp                            |
 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 * |             SGT               |P|    FT   |   Hw ID   |D|Gra|O|
 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *
 *      Platform Specific SubHeader (8 octets, optional)
 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 * |  Platf ID |               Platform Specific Info              |
 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 * |                  Platform Specific Info                       |
 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *
 * GRE proto ERSPAN type I/II = 0x88BE, type III = 0x22EB
 */

#include <uapi/linux/erspan.h>

#define ERSPAN_VERSION	0x1	/* ERSPAN type II */
#define VER_MASK	0xf000
#define VLAN_MASK	0x0fff
#define COS_MASK	0xe000
#define EN_MASK		0x1800
#define T_MASK		0x0400
#define ID_MASK		0x03ff
#define INDEX_MASK	0xfffff

#define ERSPAN_VERSION2	0x2	/* ERSPAN type III*/
#define BSO_MASK	EN_MASK
#define SGT_MASK	0xffff0000
#define P_MASK		0x8000
#define FT_MASK		0x7c00
#define HWID_MASK	0x03f0
#define DIR_MASK	0x0008
#define GRA_MASK	0x0006
#define O_MASK		0x0001

#define HWID_OFFSET    4
#define DIR_OFFSET     3

enum erspan_encap_type {
	ERSPAN_ENCAP_NOVLAN = 0x0,	/* originally without VLAN tag */
	ERSPAN_ENCAP_ISL = 0x1,		/* originally ISL encapsulated */
	ERSPAN_ENCAP_8021Q = 0x2,	/* originally 802.1Q encapsulated */
	ERSPAN_ENCAP_INFRAME = 0x3,	/* VLAN tag perserved in frame */
};

#define ERSPAN_V1_MDSIZE	4
#define ERSPAN_V2_MDSIZE	8

struct erspan_base_hdr {
#if defined(__LITTLE_ENDIAN_BITFIELD)
	__u8	vlan_upper:4,
		ver:4;
	__u8	vlan:8;
	__u8	session_id_upper:2,
		t:1,
		en:2,
		cos:3;
	__u8	session_id:8;
#elif defined(__BIG_ENDIAN_BITFIELD)
	__u8	ver: 4,
		vlan_upper:4;
	__u8	vlan:8;
	__u8	cos:3,
		en:2,
		t:1,
		session_id_upper:2;
	__u8	session_id:8;
#else
#error "Please fix <asm/byteorder.h>"
#endif
};

static inline void set_session_id(struct erspan_base_hdr *ershdr, u16 id)
{
	ershdr->session_id = id & 0xff;
	ershdr->session_id_upper = (id >> 8) & 0x3;
}

static inline u16 get_session_id(const struct erspan_base_hdr *ershdr)
{
	return (ershdr->session_id_upper << 8) + ershdr->session_id;
}

static inline void set_vlan(struct erspan_base_hdr *ershdr, u16 vlan)
{
	ershdr->vlan = vlan & 0xff;
	ershdr->vlan_upper = (vlan >> 8) & 0xf;
}

static inline u16 get_vlan(const struct erspan_base_hdr *ershdr)
{
	return (ershdr->vlan_upper << 8) + ershdr->vlan;
}

static inline void set_hwid(struct erspan_md2 *md2, u8 hwid)
{
	md2->hwid = hwid & 0xf;
	md2->hwid_upper = (hwid >> 4) & 0x3;
}

static inline u8 get_hwid(const struct erspan_md2 *md2)
{
	return (md2->hwid_upper << 4) + md2->hwid;
}

static inline int erspan_hdr_len(int version)
{
	if (version == 0)
		return 0;

	return sizeof(struct erspan_base_hdr) +
	       (version == 1 ? ERSPAN_V1_MDSIZE : ERSPAN_V2_MDSIZE);
}

static inline u8 tos_to_cos(u8 tos)
{
	u8 dscp, cos;

	dscp = tos >> 2;
	cos = dscp >> 3;
	return cos;
}

static inline void erspan_build_header(struct sk_buff *skb,
				u32 id, u32 index,
				bool truncate, bool is_ipv4)
{
	struct ethhdr *eth = (struct ethhdr *)skb->data;
	enum erspan_encap_type enc_type;
	struct erspan_base_hdr *ershdr;
	struct qtag_prefix {
		__be16 eth_type;
		__be16 tci;
	} *qp;
	u16 vlan_tci = 0;
	u8 tos;
	__be32 *idx;

	tos = is_ipv4 ? ip_hdr(skb)->tos :
			(ipv6_hdr(skb)->priority << 4) +
			(ipv6_hdr(skb)->flow_lbl[0] >> 4);

	enc_type = ERSPAN_ENCAP_NOVLAN;

	/* If mirrored packet has vlan tag, extract tci and
	 *  perserve vlan header in the mirrored frame.
	 */
	if (eth->h_proto == htons(ETH_P_8021Q)) {
		qp = (struct qtag_prefix *)(skb->data + 2 * ETH_ALEN);
		vlan_tci = ntohs(qp->tci);
		enc_type = ERSPAN_ENCAP_INFRAME;
	}

	skb_push(skb, sizeof(*ershdr) + ERSPAN_V1_MDSIZE);
	ershdr = (struct erspan_base_hdr *)skb->data;
	memset(ershdr, 0, sizeof(*ershdr) + ERSPAN_V1_MDSIZE);

	/* Build base header */
	ershdr->ver = ERSPAN_VERSION;
	ershdr->cos = tos_to_cos(tos);
	ershdr->en = enc_type;
	ershdr->t = truncate;
	set_vlan(ershdr, vlan_tci);
	set_session_id(ershdr, id);

	/* Build metadata */
	idx = (__be32 *)(ershdr + 1);
	*idx = htonl(index & INDEX_MASK);
}

/* ERSPAN GRA: timestamp granularity
 *   00b --> granularity = 100 microseconds
 *   01b --> granularity = 100 nanoseconds
 *   10b --> granularity = IEEE 1588
 * Here we only support 100 microseconds.
 */
static inline __be32 erspan_get_timestamp(void)
{
	u64 h_usecs;
	ktime_t kt;

	kt = ktime_get_real();
	h_usecs = ktime_divns(kt, 100 * NSEC_PER_USEC);

	/* ERSPAN base header only has 32-bit,
	 * so it wraps around 4 days.
	 */
	return htonl((u32)h_usecs);
}

/* ERSPAN BSO (Bad/Short/Oversized), see RFC1757
 *   00b --> Good frame with no error, or unknown integrity
 *   01b --> Payload is a Short Frame
 *   10b --> Payload is an Oversized Frame
 *   11b --> Payload is a Bad Frame with CRC or Alignment Error
 */
enum erspan_bso {
	BSO_NOERROR = 0x0,
	BSO_SHORT = 0x1,
	BSO_OVERSIZED = 0x2,
	BSO_BAD = 0x3,
};

static inline u8 erspan_detect_bso(struct sk_buff *skb)
{
	/* BSO_BAD is not handled because the frame CRC
	 * or alignment error information is in FCS.
	 */
	if (skb->len < ETH_ZLEN)
		return BSO_SHORT;

	if (skb->len > ETH_FRAME_LEN)
		return BSO_OVERSIZED;

	return BSO_NOERROR;
}

static inline void erspan_build_header_v2(struct sk_buff *skb,
					  u32 id, u8 direction, u16 hwid,
					  bool truncate, bool is_ipv4)
{
	struct ethhdr *eth = (struct ethhdr *)skb->data;
	struct erspan_base_hdr *ershdr;
	struct erspan_md2 *md2;
	struct qtag_prefix {
		__be16 eth_type;
		__be16 tci;
	} *qp;
	u16 vlan_tci = 0;
	u8 gra = 0; /* 100 usec */
	u8 bso = 0; /* Bad/Short/Oversized */
	u8 sgt = 0;
	u8 tos;

	tos = is_ipv4 ? ip_hdr(skb)->tos :
			(ipv6_hdr(skb)->priority << 4) +
			(ipv6_hdr(skb)->flow_lbl[0] >> 4);

	/* Unlike v1, v2 does not have En field,
	 * so only extract vlan tci field.
	 */
	if (eth->h_proto == htons(ETH_P_8021Q)) {
		qp = (struct qtag_prefix *)(skb->data + 2 * ETH_ALEN);
		vlan_tci = ntohs(qp->tci);
	}

	bso = erspan_detect_bso(skb);
	skb_push(skb, sizeof(*ershdr) + ERSPAN_V2_MDSIZE);
	ershdr = (struct erspan_base_hdr *)skb->data;
	memset(ershdr, 0, sizeof(*ershdr) + ERSPAN_V2_MDSIZE);

	/* Build base header */
	ershdr->ver = ERSPAN_VERSION2;
	ershdr->cos = tos_to_cos(tos);
	ershdr->en = bso;
	ershdr->t = truncate;
	set_vlan(ershdr, vlan_tci);
	set_session_id(ershdr, id);

	/* Build metadata */
	md2 = (struct erspan_md2 *)(ershdr + 1);
	md2->timestamp = erspan_get_timestamp();
	md2->sgt = htons(sgt);
	md2->p = 1;
	md2->ft = 0;
	md2->dir = direction;
	md2->gra = gra;
	md2->o = 0;
	set_hwid(md2, hwid);
}

#endif
Commit	Line	Data
84e54fe0 WT	1	#ifndef __LINUX_ERSPAN_H
	2	#define __LINUX_ERSPAN_H
	3
	4	/*
f989d546 WT	5	* GRE header for ERSPAN type I encapsulation (4 octets [34:37])
	6	* 0 1 2 3
	7	* 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
	8	* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	9	* \|0\|0\|0\|0\|0\|00000\|000000000\|00000\| Protocol Type for ERSPAN \|
	10	* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	11	*
	12	* The Type I ERSPAN frame format is based on the barebones IP + GRE
	13	* encapsulation (as described above) on top of the raw mirrored frame.
	14	* There is no extra ERSPAN header.
	15	*
	16	*
	17	* GRE header for ERSPAN type II and II encapsulation (8 octets [34:41])
84e54fe0 WT	18	* 0 1 2 3
	19	* 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
	20	* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	21	* \|0\|0\|0\|1\|0\|00000\|000000000\|00000\| Protocol Type for ERSPAN \|
	22	* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	23	* \| Sequence Number (increments per packet per session) \|
	24	* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	25	*
	26	* Note that in the above GRE header [RFC1701] out of the C, R, K, S,
	27	* s, Recur, Flags, Version fields only S (bit 03) is set to 1. The
	28	* other fields are set to zero, so only a sequence number follows.
	29	*
1d7e2ed2	30	* ERSPAN Version 1 (Type II) header (8 octets [42:49])
84e54fe0 WT	31	* 0 1 2 3
	32	* 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
	33	* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	34	* \| Ver \| VLAN \| COS \| En\|T\| Session ID \|
	35	* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	36	* \| Reserved \| Index \|
	37	* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	38	*
f551c91d WT	39	*
	40	* ERSPAN Version 2 (Type III) header (12 octets [42:49])
	41	* 0 1 2 3
	42	* 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
	43	* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	44	* \| Ver \| VLAN \| COS \|BSO\|T\| Session ID \|
	45	* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	46	* \| Timestamp \|
	47	* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	48	* \| SGT \|P\| FT \| Hw ID \|D\|Gra\|O\|
	49	* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	50	*
	51	* Platform Specific SubHeader (8 octets, optional)
	52	* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	53	* \| Platf ID \| Platform Specific Info \|
	54	* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	55	* \| Platform Specific Info \|
	56	* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	57	*
f989d546	58	* GRE proto ERSPAN type I/II = 0x88BE, type III = 0x22EB
84e54fe0 WT	59	*/
84e54fe0 WT	60
d350a823 WT	61	#include <uapi/linux/erspan.h>
d350a823 WT	62
1d7e2ed2	63	#define ERSPAN_VERSION 0x1 /* ERSPAN type II */
84e54fe0 WT	64	#define VER_MASK 0xf000
	65	#define VLAN_MASK 0x0fff
	66	#define COS_MASK 0xe000
	67	#define EN_MASK 0x1800
	68	#define T_MASK 0x0400
	69	#define ID_MASK 0x03ff
	70	#define INDEX_MASK 0xfffff
	71
f551c91d WT	72	#define ERSPAN_VERSION2 0x2 /* ERSPAN type III*/
	73	#define BSO_MASK EN_MASK
	74	#define SGT_MASK 0xffff0000
	75	#define P_MASK 0x8000
	76	#define FT_MASK 0x7c00
	77	#define HWID_MASK 0x03f0
	78	#define DIR_MASK 0x0008
	79	#define GRA_MASK 0x0006
	80	#define O_MASK 0x0001
	81
c69de58b WT	82	#define HWID_OFFSET 4
	83	#define DIR_OFFSET 3
	84
84e54fe0 WT	85	enum erspan_encap_type {
	86	ERSPAN_ENCAP_NOVLAN = 0x0, /* originally without VLAN tag */
	87	ERSPAN_ENCAP_ISL = 0x1, /* originally ISL encapsulated */
	88	ERSPAN_ENCAP_8021Q = 0x2, /* originally 802.1Q encapsulated */
	89	ERSPAN_ENCAP_INFRAME = 0x3, /* VLAN tag perserved in frame */
	90	};
	91
1d7e2ed2 WT	92	#define ERSPAN_V1_MDSIZE 4
1d7e2ed2 WT	93	#define ERSPAN_V2_MDSIZE 8
84e54fe0	94
1d7e2ed2	95	struct erspan_base_hdr {
c69de58b WT	96	#if defined(__LITTLE_ENDIAN_BITFIELD)
	97	__u8 vlan_upper:4,
	98	ver:4;
	99	__u8 vlan:8;
	100	__u8 session_id_upper:2,
	101	t:1,
	102	en:2,
	103	cos:3;
	104	__u8 session_id:8;
	105	#elif defined(__BIG_ENDIAN_BITFIELD)
	106	__u8 ver: 4,
	107	vlan_upper:4;
	108	__u8 vlan:8;
	109	__u8 cos:3,
	110	en:2,
	111	t:1,
	112	session_id_upper:2;
	113	__u8 session_id:8;
	114	#else
	115	#error "Please fix <asm/byteorder.h>"
	116	#endif
84e54fe0 WT	117	};
84e54fe0 WT	118
c69de58b WT	119	static inline void set_session_id(struct erspan_base_hdr *ershdr, u16 id)
	120	{
	121	ershdr->session_id = id & 0xff;
	122	ershdr->session_id_upper = (id >> 8) & 0x3;
	123	}
	124
	125	static inline u16 get_session_id(const struct erspan_base_hdr *ershdr)
	126	{
	127	return (ershdr->session_id_upper << 8) + ershdr->session_id;
	128	}
	129
	130	static inline void set_vlan(struct erspan_base_hdr *ershdr, u16 vlan)
	131	{
	132	ershdr->vlan = vlan & 0xff;
	133	ershdr->vlan_upper = (vlan >> 8) & 0xf;
	134	}
	135
	136	static inline u16 get_vlan(const struct erspan_base_hdr *ershdr)
	137	{
	138	return (ershdr->vlan_upper << 8) + ershdr->vlan;
	139	}
	140
	141	static inline void set_hwid(struct erspan_md2 *md2, u8 hwid)
	142	{
	143	md2->hwid = hwid & 0xf;
	144	md2->hwid_upper = (hwid >> 4) & 0x3;
	145	}
	146
	147	static inline u8 get_hwid(const struct erspan_md2 *md2)
	148	{
	149	return (md2->hwid_upper << 4) + md2->hwid;
	150	}
	151
1d7e2ed2 WT	152	static inline int erspan_hdr_len(int version)
1d7e2ed2 WT	153	{
f989d546 WT	154	if (version == 0)
	155	return 0;
	156
1d7e2ed2 WT	157	return sizeof(struct erspan_base_hdr) +
	158	(version == 1 ? ERSPAN_V1_MDSIZE : ERSPAN_V2_MDSIZE);
	159	}
	160
a3222dc9 WT	161	static inline u8 tos_to_cos(u8 tos)
	162	{
	163	u8 dscp, cos;
	164
	165	dscp = tos >> 2;
	166	cos = dscp >> 3;
	167	return cos;
	168	}
	169
	170	static inline void erspan_build_header(struct sk_buff *skb,
c69de58b	171	u32 id, u32 index,
a3222dc9 WT	172	bool truncate, bool is_ipv4)
a3222dc9 WT	173	{
b423d13c	174	struct ethhdr eth = (struct ethhdr )skb->data;
a3222dc9	175	enum erspan_encap_type enc_type;
1d7e2ed2	176	struct erspan_base_hdr *ershdr;
a3222dc9 WT	177	struct qtag_prefix {
	178	__be16 eth_type;
	179	__be16 tci;
	180	} *qp;
	181	u16 vlan_tci = 0;
	182	u8 tos;
3df19283	183	__be32 *idx;
a3222dc9 WT	184
	185	tos = is_ipv4 ? ip_hdr(skb)->tos :
	186	(ipv6_hdr(skb)->priority << 4) +
	187	(ipv6_hdr(skb)->flow_lbl[0] >> 4);
	188
	189	enc_type = ERSPAN_ENCAP_NOVLAN;
	190
	191	/* If mirrored packet has vlan tag, extract tci and
	192	* perserve vlan header in the mirrored frame.
	193	*/
	194	if (eth->h_proto == htons(ETH_P_8021Q)) {
	195	qp = (struct qtag_prefix )(skb->data + 2 ETH_ALEN);
	196	vlan_tci = ntohs(qp->tci);
	197	enc_type = ERSPAN_ENCAP_INFRAME;
	198	}
	199
1d7e2ed2 WT	200	skb_push(skb, sizeof(*ershdr) + ERSPAN_V1_MDSIZE);
	201	ershdr = (struct erspan_base_hdr *)skb->data;
	202	memset(ershdr, 0, sizeof(*ershdr) + ERSPAN_V1_MDSIZE);
a3222dc9	203
1d7e2ed2	204	/* Build base header */
c69de58b WT	205	ershdr->ver = ERSPAN_VERSION;
	206	ershdr->cos = tos_to_cos(tos);
	207	ershdr->en = enc_type;
	208	ershdr->t = truncate;
	209	set_vlan(ershdr, vlan_tci);
	210	set_session_id(ershdr, id);
1d7e2ed2 WT	211
1d7e2ed2 WT	212	/* Build metadata */
3df19283 WT	213	idx = (__be32 *)(ershdr + 1);
3df19283 WT	214	*idx = htonl(index & INDEX_MASK);
a3222dc9 WT	215	}
a3222dc9 WT	216
f551c91d WT	217	/* ERSPAN GRA: timestamp granularity
	218	* 00b --> granularity = 100 microseconds
	219	* 01b --> granularity = 100 nanoseconds
	220	* 10b --> granularity = IEEE 1588
	221	* Here we only support 100 microseconds.
	222	*/
	223	static inline __be32 erspan_get_timestamp(void)
	224	{
	225	u64 h_usecs;
	226	ktime_t kt;
	227
	228	kt = ktime_get_real();
	229	h_usecs = ktime_divns(kt, 100 * NSEC_PER_USEC);
	230
	231	/* ERSPAN base header only has 32-bit,
	232	* so it wraps around 4 days.
	233	*/
	234	return htonl((u32)h_usecs);
	235	}
	236
d48f1958 WT	237	/* ERSPAN BSO (Bad/Short/Oversized), see RFC1757
	238	* 00b --> Good frame with no error, or unknown integrity
	239	* 01b --> Payload is a Short Frame
	240	* 10b --> Payload is an Oversized Frame
	241	* 11b --> Payload is a Bad Frame with CRC or Alignment Error
	242	*/
	243	enum erspan_bso {
	244	BSO_NOERROR = 0x0,
	245	BSO_SHORT = 0x1,
	246	BSO_OVERSIZED = 0x2,
	247	BSO_BAD = 0x3,
	248	};
	249
	250	static inline u8 erspan_detect_bso(struct sk_buff *skb)
	251	{
	252	/* BSO_BAD is not handled because the frame CRC
	253	* or alignment error information is in FCS.
	254	*/
	255	if (skb->len < ETH_ZLEN)
	256	return BSO_SHORT;
	257
	258	if (skb->len > ETH_FRAME_LEN)
	259	return BSO_OVERSIZED;
	260
	261	return BSO_NOERROR;
	262	}
	263
f551c91d	264	static inline void erspan_build_header_v2(struct sk_buff *skb,
c69de58b	265	u32 id, u8 direction, u16 hwid,
f551c91d WT	266	bool truncate, bool is_ipv4)
f551c91d WT	267	{
b423d13c	268	struct ethhdr eth = (struct ethhdr )skb->data;
f551c91d	269	struct erspan_base_hdr *ershdr;
3df19283	270	struct erspan_md2 *md2;
f551c91d WT	271	struct qtag_prefix {
	272	__be16 eth_type;
	273	__be16 tci;
	274	} *qp;
	275	u16 vlan_tci = 0;
f551c91d WT	276	u8 gra = 0; /* 100 usec */
	277	u8 bso = 0; /* Bad/Short/Oversized */
	278	u8 sgt = 0;
	279	u8 tos;
	280
	281	tos = is_ipv4 ? ip_hdr(skb)->tos :
	282	(ipv6_hdr(skb)->priority << 4) +
	283	(ipv6_hdr(skb)->flow_lbl[0] >> 4);
	284
	285	/* Unlike v1, v2 does not have En field,
	286	* so only extract vlan tci field.
	287	*/
	288	if (eth->h_proto == htons(ETH_P_8021Q)) {
	289	qp = (struct qtag_prefix )(skb->data + 2 ETH_ALEN);
	290	vlan_tci = ntohs(qp->tci);
	291	}
	292
d48f1958	293	bso = erspan_detect_bso(skb);
f551c91d WT	294	skb_push(skb, sizeof(*ershdr) + ERSPAN_V2_MDSIZE);
	295	ershdr = (struct erspan_base_hdr *)skb->data;
	296	memset(ershdr, 0, sizeof(*ershdr) + ERSPAN_V2_MDSIZE);
	297
	298	/* Build base header */
c69de58b WT	299	ershdr->ver = ERSPAN_VERSION2;
	300	ershdr->cos = tos_to_cos(tos);
	301	ershdr->en = bso;
	302	ershdr->t = truncate;
	303	set_vlan(ershdr, vlan_tci);
	304	set_session_id(ershdr, id);
f551c91d WT	305
f551c91d WT	306	/* Build metadata */
3df19283 WT	307	md2 = (struct erspan_md2 *)(ershdr + 1);
	308	md2->timestamp = erspan_get_timestamp();
	309	md2->sgt = htons(sgt);
	310	md2->p = 1;
	311	md2->ft = 0;
	312	md2->dir = direction;
	313	md2->gra = gra;
	314	md2->o = 0;
	315	set_hwid(md2, hwid);
f551c91d WT	316	}
f551c91d WT	317
84e54fe0	318	#endif