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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
commit | 2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch) | |
tree | 848558de17fb3008cdf4d861b01ac7781903ce39 /include/net/erspan.h | |
parent | Initial commit. (diff) | |
download | linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip |
Adding upstream version 6.1.76.upstream/6.1.76upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to '')
-rw-r--r-- | include/net/erspan.h | 321 |
1 files changed, 321 insertions, 0 deletions
diff --git a/include/net/erspan.h b/include/net/erspan.h new file mode 100644 index 000000000..6cb4cbd6a --- /dev/null +++ b/include/net/erspan.h @@ -0,0 +1,321 @@ +#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 <linux/ip.h> +#include <linux/ipv6.h> +#include <linux/skbuff.h> +#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 |