new file mode 100644
@@ -0,0 +1,61 @@
+#ifndef __LINUX_ERSPAN_H
+#define __LINUX_ERSPAN_H
+
+/*
+ * GRE header for ERSPAN encapsulation (8 octets [34:41]) -- 8 bytes
+ * 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 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 |
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ *
+ * GRE proto ERSPAN type II = 0x88BE, type III = 0x22EB
+ */
+
+#define ERSPAN_VERSION 0x1
+
+#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
+
+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 */
+};
+
+struct erspan_metadata {
+ __be32 index; /* type II */
+};
+
+struct erspanhdr {
+ __be16 ver_vlan;
+#define VER_OFFSET 12
+ __be16 session_id;
+#define COS_OFFSET 13
+#define EN_OFFSET 11
+#define T_OFFSET 10
+ struct erspan_metadata md;
+};
+
+#endif
@@ -115,6 +115,9 @@ struct ip_tunnel {
u32 o_seqno; /* The last output seqno */
int tun_hlen; /* Precalculated header length */
+ /* This field used only by ERSPAN */
+ u32 index; /* ERSPAN type II index */
+
struct dst_cache dst_cache;
struct ip_tunnel_parm parms;
@@ -66,6 +66,7 @@
#define ETH_P_ATALK 0x809B /* Appletalk DDP */
#define ETH_P_AARP 0x80F3 /* Appletalk AARP */
#define ETH_P_8021Q 0x8100 /* 802.1Q VLAN Extended Header */
+#define ETH_P_ERSPAN 0x88BE /* ERSPAN type II */
#define ETH_P_IPX 0x8137 /* IPX over DIX */
#define ETH_P_IPV6 0x86DD /* IPv6 over bluebook */
#define ETH_P_PAUSE 0x8808 /* IEEE Pause frames. See 802.3 31B */
@@ -134,6 +134,7 @@ enum {
IFLA_GRE_COLLECT_METADATA,
IFLA_GRE_IGNORE_DF,
IFLA_GRE_FWMARK,
+ IFLA_GRE_ERSPAN_INDEX,
__IFLA_GRE_MAX,
};
@@ -48,6 +48,7 @@
#include <net/rtnetlink.h>
#include <net/gre.h>
#include <net/dst_metadata.h>
+#include <net/erspan.h>
/*
Problems & solutions
@@ -115,6 +116,7 @@ static int ipgre_tunnel_init(struct net_device *dev);
static unsigned int ipgre_net_id __read_mostly;
static unsigned int gre_tap_net_id __read_mostly;
+static unsigned int erspan_net_id __read_mostly;
static void ipgre_err(struct sk_buff *skb, u32 info,
const struct tnl_ptk_info *tpi)
@@ -246,6 +248,56 @@ static void gre_err(struct sk_buff *skb, u32 info)
ipgre_err(skb, info, &tpi);
}
+static int erspan_rcv(struct sk_buff *skb, struct tnl_ptk_info *tpi,
+ int gre_hdr_len)
+{
+ struct net *net = dev_net(skb->dev);
+ struct metadata_dst *tun_dst = NULL;
+ struct ip_tunnel_net *itn;
+ struct ip_tunnel *tunnel;
+ struct erspanhdr *ershdr;
+ const struct iphdr *iph;
+ __be32 session_id;
+ __be32 index;
+ int len;
+
+ itn = net_generic(net, erspan_net_id);
+ iph = ip_hdr(skb);
+ len = gre_hdr_len + sizeof(*ershdr);
+
+ if (unlikely(!pskb_may_pull(skb, len)))
+ return -ENOMEM;
+
+ iph = ip_hdr(skb);
+ ershdr = (struct erspanhdr *)(skb->data + gre_hdr_len);
+
+ /* The original GRE header does not have key field,
+ * Use ERSPAN 10-bit session ID as key.
+ */
+ session_id = cpu_to_be32(ntohs(ershdr->session_id));
+ tpi->key = session_id;
+ index = ershdr->md.index;
+ tunnel = ip_tunnel_lookup(itn, skb->dev->ifindex,
+ tpi->flags | TUNNEL_KEY,
+ iph->saddr, iph->daddr, tpi->key);
+
+ if (tunnel) {
+ if (__iptunnel_pull_header(skb,
+ gre_hdr_len + sizeof(*ershdr),
+ htons(ETH_P_TEB),
+ false, false) < 0)
+ goto drop;
+
+ tunnel->index = ntohl(index);
+ skb_reset_mac_header(skb);
+ ip_tunnel_rcv(tunnel, skb, tpi, tun_dst, log_ecn_error);
+ return PACKET_RCVD;
+ }
+drop:
+ kfree_skb(skb);
+ return PACKET_RCVD;
+}
+
static int __ipgre_rcv(struct sk_buff *skb, const struct tnl_ptk_info *tpi,
struct ip_tunnel_net *itn, int hdr_len, bool raw_proto)
{
@@ -328,6 +380,11 @@ static int gre_rcv(struct sk_buff *skb)
if (hdr_len < 0)
goto drop;
+ if (unlikely(tpi.proto == htons(ETH_P_ERSPAN))) {
+ if (erspan_rcv(skb, &tpi, hdr_len) == PACKET_RCVD)
+ return 0;
+ }
+
if (ipgre_rcv(skb, &tpi, hdr_len) == PACKET_RCVD)
return 0;
@@ -503,6 +560,81 @@ static netdev_tx_t ipgre_xmit(struct sk_buff *skb,
return NETDEV_TX_OK;
}
+static inline u8 tos_to_cos(u8 tos)
+{
+ u8 dscp, cos;
+
+ dscp = tos >> 2;
+ cos = dscp >> 3;
+ return cos;
+}
+
+static void erspan_build_header(struct sk_buff *skb,
+ __be32 id, u32 index, bool truncate)
+{
+ struct iphdr *iphdr = ip_hdr(skb);
+ struct ethhdr *eth = eth_hdr(skb);
+ enum erspan_encap_type enc_type;
+ struct erspanhdr *ershdr;
+ struct qtag_prefix {
+ __be16 eth_type;
+ __be16 tci;
+ } *qp;
+ u16 vlan_tci = 0;
+
+ 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));
+ ershdr = (struct erspanhdr *)skb->data;
+ memset(ershdr, 0, sizeof(*ershdr));
+
+ ershdr->ver_vlan = htons((vlan_tci & VLAN_MASK) |
+ (ERSPAN_VERSION << VER_OFFSET));
+ ershdr->session_id = htons((u16)(ntohl(id) & ID_MASK) |
+ ((tos_to_cos(iphdr->tos) << COS_OFFSET) & COS_MASK) |
+ (enc_type << EN_OFFSET & EN_MASK) |
+ ((truncate << T_OFFSET) & T_MASK));
+ ershdr->md.index = htonl(index & INDEX_MASK);
+}
+
+static netdev_tx_t erspan_xmit(struct sk_buff *skb,
+ struct net_device *dev)
+{
+ struct ip_tunnel *tunnel = netdev_priv(dev);
+ bool truncate = false;
+
+ if (gre_handle_offloads(skb, false))
+ goto free_skb;
+
+ if (skb_cow_head(skb, dev->needed_headroom))
+ goto free_skb;
+
+ if (skb->len > dev->mtu) {
+ pskb_trim(skb, dev->mtu);
+ truncate = true;
+ }
+
+ /* Push ERSPAN header */
+ erspan_build_header(skb, tunnel->parms.o_key, tunnel->index, truncate);
+ tunnel->parms.o_flags &= ~TUNNEL_KEY;
+ __gre_xmit(skb, dev, &tunnel->parms.iph, htons(ETH_P_ERSPAN));
+ return NETDEV_TX_OK;
+
+free_skb:
+ kfree_skb(skb);
+ dev->stats.tx_dropped++;
+ return NETDEV_TX_OK;
+}
+
static netdev_tx_t gre_tap_xmit(struct sk_buff *skb,
struct net_device *dev)
{
@@ -828,6 +960,39 @@ static int ipgre_tap_validate(struct nlattr *tb[], struct nlattr *data[],
return ipgre_tunnel_validate(tb, data, extack);
}
+static int erspan_validate(struct nlattr *tb[], struct nlattr *data[],
+ struct netlink_ext_ack *extack)
+{
+ __be16 flags = 0;
+ int ret;
+
+ if (!data)
+ return 0;
+
+ ret = ipgre_tap_validate(tb, data, extack);
+ if (ret)
+ return ret;
+
+ /* ERSPAN should only have GRE sequence and key flag */
+ flags |= nla_get_be16(data[IFLA_GRE_OFLAGS]);
+ flags |= nla_get_be16(data[IFLA_GRE_IFLAGS]);
+ if (flags != (GRE_SEQ | GRE_KEY))
+ return -EINVAL;
+
+ /* ERSPAN Session ID only has 10-bit. Since we reuse
+ * 32-bit key field as ID, check it's range.
+ */
+ if (data[IFLA_GRE_IKEY] &&
+ (ntohl(nla_get_be32(data[IFLA_GRE_IKEY])) & ~ID_MASK))
+ return -EINVAL;
+
+ if (data[IFLA_GRE_OKEY] &&
+ (ntohl(nla_get_be32(data[IFLA_GRE_OKEY])) & ~ID_MASK))
+ return -EINVAL;
+
+ return 0;
+}
+
static int ipgre_netlink_parms(struct net_device *dev,
struct nlattr *data[],
struct nlattr *tb[],
@@ -892,6 +1057,13 @@ static int ipgre_netlink_parms(struct net_device *dev,
if (data[IFLA_GRE_FWMARK])
*fwmark = nla_get_u32(data[IFLA_GRE_FWMARK]);
+ if (data[IFLA_GRE_ERSPAN_INDEX]) {
+ t->index = nla_get_u32(data[IFLA_GRE_ERSPAN_INDEX]);
+
+ if (t->index & ~INDEX_MASK)
+ return -EINVAL;
+ }
+
return 0;
}
@@ -949,6 +1121,36 @@ static const struct net_device_ops gre_tap_netdev_ops = {
.ndo_fill_metadata_dst = gre_fill_metadata_dst,
};
+static int erspan_tunnel_init(struct net_device *dev)
+{
+ struct ip_tunnel *tunnel = netdev_priv(dev);
+ int t_hlen;
+
+ tunnel->tun_hlen = 8;
+ tunnel->parms.iph.protocol = IPPROTO_GRE;
+ t_hlen = tunnel->hlen + sizeof(struct iphdr) + sizeof(struct erspanhdr);
+
+ dev->needed_headroom = LL_MAX_HEADER + t_hlen + 4;
+ dev->mtu = ETH_DATA_LEN - t_hlen - 4;
+ dev->features |= GRE_FEATURES;
+ dev->hw_features |= GRE_FEATURES;
+ dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
+
+ return ip_tunnel_init(dev);
+}
+
+static const struct net_device_ops erspan_netdev_ops = {
+ .ndo_init = erspan_tunnel_init,
+ .ndo_uninit = ip_tunnel_uninit,
+ .ndo_start_xmit = erspan_xmit,
+ .ndo_set_mac_address = eth_mac_addr,
+ .ndo_validate_addr = eth_validate_addr,
+ .ndo_change_mtu = ip_tunnel_change_mtu,
+ .ndo_get_stats64 = ip_tunnel_get_stats64,
+ .ndo_get_iflink = ip_tunnel_get_iflink,
+ .ndo_fill_metadata_dst = gre_fill_metadata_dst,
+};
+
static void ipgre_tap_setup(struct net_device *dev)
{
ether_setup(dev);
@@ -1041,6 +1243,8 @@ static size_t ipgre_get_size(const struct net_device *dev)
nla_total_size(1) +
/* IFLA_GRE_FWMARK */
nla_total_size(4) +
+ /* IFLA_GRE_ERSPAN_INDEX */
+ nla_total_size(4) +
0;
}
@@ -1083,12 +1287,25 @@ static int ipgre_fill_info(struct sk_buff *skb, const struct net_device *dev)
goto nla_put_failure;
}
+ if (t->index)
+ if (nla_put_u32(skb, IFLA_GRE_ERSPAN_INDEX, t->index))
+ goto nla_put_failure;
+
return 0;
nla_put_failure:
return -EMSGSIZE;
}
+static void erspan_setup(struct net_device *dev)
+{
+ ether_setup(dev);
+ dev->netdev_ops = &erspan_netdev_ops;
+ dev->priv_flags &= ~IFF_TX_SKB_SHARING;
+ dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
+ ip_tunnel_setup(dev, erspan_net_id);
+}
+
static const struct nla_policy ipgre_policy[IFLA_GRE_MAX + 1] = {
[IFLA_GRE_LINK] = { .type = NLA_U32 },
[IFLA_GRE_IFLAGS] = { .type = NLA_U16 },
@@ -1107,6 +1324,7 @@ static const struct nla_policy ipgre_policy[IFLA_GRE_MAX + 1] = {
[IFLA_GRE_COLLECT_METADATA] = { .type = NLA_FLAG },
[IFLA_GRE_IGNORE_DF] = { .type = NLA_U8 },
[IFLA_GRE_FWMARK] = { .type = NLA_U32 },
+ [IFLA_GRE_ERSPAN_INDEX] = { .type = NLA_U32 },
};
static struct rtnl_link_ops ipgre_link_ops __read_mostly = {
@@ -1139,6 +1357,21 @@ static struct rtnl_link_ops ipgre_tap_ops __read_mostly = {
.get_link_net = ip_tunnel_get_link_net,
};
+static struct rtnl_link_ops erspan_link_ops __read_mostly = {
+ .kind = "erspan",
+ .maxtype = IFLA_GRE_MAX,
+ .policy = ipgre_policy,
+ .priv_size = sizeof(struct ip_tunnel),
+ .setup = erspan_setup,
+ .validate = erspan_validate,
+ .newlink = ipgre_newlink,
+ .changelink = ipgre_changelink,
+ .dellink = ip_tunnel_dellink,
+ .get_size = ipgre_get_size,
+ .fill_info = ipgre_fill_info,
+ .get_link_net = ip_tunnel_get_link_net,
+};
+
struct net_device *gretap_fb_dev_create(struct net *net, const char *name,
u8 name_assign_type)
{
@@ -1202,6 +1435,26 @@ static struct pernet_operations ipgre_tap_net_ops = {
.size = sizeof(struct ip_tunnel_net),
};
+static int __net_init erspan_init_net(struct net *net)
+{
+ return ip_tunnel_init_net(net, erspan_net_id,
+ &erspan_link_ops, "erspan0");
+}
+
+static void __net_exit erspan_exit_net(struct net *net)
+{
+ struct ip_tunnel_net *itn = net_generic(net, erspan_net_id);
+
+ ip_tunnel_delete_net(itn, &erspan_link_ops);
+}
+
+static struct pernet_operations erspan_net_ops = {
+ .init = erspan_init_net,
+ .exit = erspan_exit_net,
+ .id = &erspan_net_id,
+ .size = sizeof(struct ip_tunnel_net),
+};
+
static int __init ipgre_init(void)
{
int err;
@@ -1216,6 +1469,10 @@ static int __init ipgre_init(void)
if (err < 0)
goto pnet_tap_faied;
+ err = register_pernet_device(&erspan_net_ops);
+ if (err < 0)
+ goto pnet_erspan_failed;
+
err = gre_add_protocol(&ipgre_protocol, GREPROTO_CISCO);
if (err < 0) {
pr_info("%s: can't add protocol\n", __func__);
@@ -1230,13 +1487,21 @@ static int __init ipgre_init(void)
if (err < 0)
goto tap_ops_failed;
+ err = rtnl_link_register(&erspan_link_ops);
+ if (err < 0)
+ goto erspan_link_failed;
+
return 0;
+erspan_link_failed:
+ rtnl_link_unregister(&ipgre_tap_ops);
tap_ops_failed:
rtnl_link_unregister(&ipgre_link_ops);
rtnl_link_failed:
gre_del_protocol(&ipgre_protocol, GREPROTO_CISCO);
add_proto_failed:
+ unregister_pernet_device(&erspan_net_ops);
+pnet_erspan_failed:
unregister_pernet_device(&ipgre_tap_net_ops);
pnet_tap_faied:
unregister_pernet_device(&ipgre_net_ops);
@@ -1247,9 +1512,11 @@ static void __exit ipgre_fini(void)
{
rtnl_link_unregister(&ipgre_tap_ops);
rtnl_link_unregister(&ipgre_link_ops);
+ rtnl_link_unregister(&erspan_link_ops);
gre_del_protocol(&ipgre_protocol, GREPROTO_CISCO);
unregister_pernet_device(&ipgre_tap_net_ops);
unregister_pernet_device(&ipgre_net_ops);
+ unregister_pernet_device(&erspan_net_ops);
}
module_init(ipgre_init);
@@ -1257,5 +1524,7 @@ module_exit(ipgre_fini);
MODULE_LICENSE("GPL");
MODULE_ALIAS_RTNL_LINK("gre");
MODULE_ALIAS_RTNL_LINK("gretap");
+MODULE_ALIAS_RTNL_LINK("erspan");
MODULE_ALIAS_NETDEV("gre0");
MODULE_ALIAS_NETDEV("gretap0");
+MODULE_ALIAS_NETDEV("erspan0");