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authorWilliam Tu <u9012063@gmail.com>2020-05-05 19:05:06 +0300
committerDavid S. Miller <davem@davemloft.net>2020-05-05 23:23:29 +0300
commitf989d546a2d5a9f001f6f8be49d98c10ab9b1897 (patch)
tree9bffb2d41538c73853c73c9e6fd9f402fb112ded /net/ipv4/ip_gre.c
parent730f135104f3afe320d0df4c53c28d6ad9d17d6b (diff)
downloadlinux-f989d546a2d5a9f001f6f8be49d98c10ab9b1897.tar.xz
erspan: Add type I version 0 support.
The Type I ERSPAN frame format is based on the barebones IP + GRE(4-byte) encapsulation on top of the raw mirrored frame. Both type I and II use 0x88BE as protocol type. Unlike type II and III, no sequence number or key is required. To creat a type I erspan tunnel device: $ ip link add dev erspan11 type erspan \ local 172.16.1.100 remote 172.16.1.200 \ erspan_ver 0 Signed-off-by: William Tu <u9012063@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/ipv4/ip_gre.c')
-rw-r--r--net/ipv4/ip_gre.c58
1 files changed, 43 insertions, 15 deletions
diff --git a/net/ipv4/ip_gre.c b/net/ipv4/ip_gre.c
index 029b24eeafba..e29cd48674d7 100644
--- a/net/ipv4/ip_gre.c
+++ b/net/ipv4/ip_gre.c
@@ -248,6 +248,15 @@ static void gre_err(struct sk_buff *skb, u32 info)
ipgre_err(skb, info, &tpi);
}
+static bool is_erspan_type1(int gre_hdr_len)
+{
+ /* Both ERSPAN type I (version 0) and type II (version 1) use
+ * protocol 0x88BE, but the type I has only 4-byte GRE header,
+ * while type II has 8-byte.
+ */
+ return gre_hdr_len == 4;
+}
+
static int erspan_rcv(struct sk_buff *skb, struct tnl_ptk_info *tpi,
int gre_hdr_len)
{
@@ -262,17 +271,26 @@ static int erspan_rcv(struct sk_buff *skb, struct tnl_ptk_info *tpi,
int len;
itn = net_generic(net, erspan_net_id);
-
iph = ip_hdr(skb);
- ershdr = (struct erspan_base_hdr *)(skb->data + gre_hdr_len);
- ver = ershdr->ver;
-
- tunnel = ip_tunnel_lookup(itn, skb->dev->ifindex,
- tpi->flags | TUNNEL_KEY,
- iph->saddr, iph->daddr, tpi->key);
+ if (is_erspan_type1(gre_hdr_len)) {
+ ver = 0;
+ tunnel = ip_tunnel_lookup(itn, skb->dev->ifindex,
+ tpi->flags | TUNNEL_NO_KEY,
+ iph->saddr, iph->daddr, 0);
+ } else {
+ ershdr = (struct erspan_base_hdr *)(skb->data + gre_hdr_len);
+ ver = ershdr->ver;
+ tunnel = ip_tunnel_lookup(itn, skb->dev->ifindex,
+ tpi->flags | TUNNEL_KEY,
+ iph->saddr, iph->daddr, tpi->key);
+ }
if (tunnel) {
- len = gre_hdr_len + erspan_hdr_len(ver);
+ if (is_erspan_type1(gre_hdr_len))
+ len = gre_hdr_len;
+ else
+ len = gre_hdr_len + erspan_hdr_len(ver);
+
if (unlikely(!pskb_may_pull(skb, len)))
return PACKET_REJECT;
@@ -665,7 +683,10 @@ static netdev_tx_t erspan_xmit(struct sk_buff *skb,
}
/* Push ERSPAN header */
- if (tunnel->erspan_ver == 1) {
+ if (tunnel->erspan_ver == 0) {
+ proto = htons(ETH_P_ERSPAN);
+ tunnel->parms.o_flags &= ~TUNNEL_SEQ;
+ } else if (tunnel->erspan_ver == 1) {
erspan_build_header(skb, ntohl(tunnel->parms.o_key),
tunnel->index,
truncate, true);
@@ -1066,7 +1087,10 @@ static int erspan_validate(struct nlattr *tb[], struct nlattr *data[],
if (ret)
return ret;
- /* ERSPAN should only have GRE sequence and key flag */
+ if (nla_get_u8(data[IFLA_GRE_ERSPAN_VER]) == 0)
+ return 0;
+
+ /* ERSPAN type II/III should only have GRE sequence and key flag */
if (data[IFLA_GRE_OFLAGS])
flags |= nla_get_be16(data[IFLA_GRE_OFLAGS]);
if (data[IFLA_GRE_IFLAGS])
@@ -1174,7 +1198,7 @@ static int erspan_netlink_parms(struct net_device *dev,
if (data[IFLA_GRE_ERSPAN_VER]) {
t->erspan_ver = nla_get_u8(data[IFLA_GRE_ERSPAN_VER]);
- if (t->erspan_ver != 1 && t->erspan_ver != 2)
+ if (t->erspan_ver > 2)
return -EINVAL;
}
@@ -1259,7 +1283,11 @@ static int erspan_tunnel_init(struct net_device *dev)
{
struct ip_tunnel *tunnel = netdev_priv(dev);
- tunnel->tun_hlen = 8;
+ if (tunnel->erspan_ver == 0)
+ tunnel->tun_hlen = 4; /* 4-byte GRE hdr. */
+ else
+ tunnel->tun_hlen = 8; /* 8-byte GRE hdr. */
+
tunnel->parms.iph.protocol = IPPROTO_GRE;
tunnel->hlen = tunnel->tun_hlen + tunnel->encap_hlen +
erspan_hdr_len(tunnel->erspan_ver);
@@ -1456,8 +1484,8 @@ static int ipgre_fill_info(struct sk_buff *skb, const struct net_device *dev)
struct ip_tunnel_parm *p = &t->parms;
__be16 o_flags = p->o_flags;
- if (t->erspan_ver == 1 || t->erspan_ver == 2) {
- if (!t->collect_md)
+ if (t->erspan_ver <= 2) {
+ if (t->erspan_ver != 0 && !t->collect_md)
o_flags |= TUNNEL_KEY;
if (nla_put_u8(skb, IFLA_GRE_ERSPAN_VER, t->erspan_ver))
@@ -1466,7 +1494,7 @@ static int ipgre_fill_info(struct sk_buff *skb, const struct net_device *dev)
if (t->erspan_ver == 1) {
if (nla_put_u32(skb, IFLA_GRE_ERSPAN_INDEX, t->index))
goto nla_put_failure;
- } else {
+ } else if (t->erspan_ver == 2) {
if (nla_put_u8(skb, IFLA_GRE_ERSPAN_DIR, t->dir))
goto nla_put_failure;
if (nla_put_u16(skb, IFLA_GRE_ERSPAN_HWID, t->hwid))