ip6_gre: add ip6 gre and gretap collect_md mode

Similar to gre, vxlan, geneve, ipip tunnels, allow ip6 gre and gretap
tunnels to operate in collect metadata mode.  bpf_skb_[gs]et_tunnel_key()
helpers can make use of it right away.  OVS can use it as well in the
future.

Signed-off-by: William Tu <u9012063@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
William Tu 2017-12-01 15:26:08 -08:00 committed by David S. Miller
parent c34bc2b505
commit 6712abc168
2 changed files with 99 additions and 11 deletions

View File

@ -56,6 +56,7 @@
#include <net/ip6_tunnel.h>
#include <net/gre.h>
#include <net/erspan.h>
#include <net/dst_metadata.h>
static bool log_ecn_error = true;
@ -69,6 +70,7 @@ static unsigned int ip6gre_net_id __read_mostly;
struct ip6gre_net {
struct ip6_tnl __rcu *tunnels[4][IP6_GRE_HASH_SIZE];
struct ip6_tnl __rcu *collect_md_tun;
struct net_device *fb_tunnel_dev;
};
@ -229,6 +231,10 @@ static struct ip6_tnl *ip6gre_tunnel_lookup(struct net_device *dev,
if (cand)
return cand;
t = rcu_dereference(ign->collect_md_tun);
if (t && t->dev->flags & IFF_UP)
return t;
dev = ign->fb_tunnel_dev;
if (dev->flags & IFF_UP)
return netdev_priv(dev);
@ -264,6 +270,9 @@ static void ip6gre_tunnel_link(struct ip6gre_net *ign, struct ip6_tnl *t)
{
struct ip6_tnl __rcu **tp = ip6gre_bucket(ign, t);
if (t->parms.collect_md)
rcu_assign_pointer(ign->collect_md_tun, t);
rcu_assign_pointer(t->next, rtnl_dereference(*tp));
rcu_assign_pointer(*tp, t);
}
@ -273,6 +282,9 @@ static void ip6gre_tunnel_unlink(struct ip6gre_net *ign, struct ip6_tnl *t)
struct ip6_tnl __rcu **tp;
struct ip6_tnl *iter;
if (t->parms.collect_md)
rcu_assign_pointer(ign->collect_md_tun, NULL);
for (tp = ip6gre_bucket(ign, t);
(iter = rtnl_dereference(*tp)) != NULL;
tp = &iter->next) {
@ -463,7 +475,22 @@ static int ip6gre_rcv(struct sk_buff *skb, const struct tnl_ptk_info *tpi)
&ipv6h->saddr, &ipv6h->daddr, tpi->key,
tpi->proto);
if (tunnel) {
if (tunnel->parms.collect_md) {
struct metadata_dst *tun_dst;
__be64 tun_id;
__be16 flags;
flags = tpi->flags;
tun_id = key32_to_tunnel_id(tpi->key);
tun_dst = ipv6_tun_rx_dst(skb, flags, tun_id, 0);
if (!tun_dst)
return PACKET_REJECT;
ip6_tnl_rcv(tunnel, skb, tpi, tun_dst, log_ecn_error);
} else {
ip6_tnl_rcv(tunnel, skb, tpi, NULL, log_ecn_error);
}
return PACKET_RCVD;
}
@ -633,8 +660,38 @@ static netdev_tx_t __gre6_xmit(struct sk_buff *skb,
/* Push GRE header. */
protocol = (dev->type == ARPHRD_ETHER) ? htons(ETH_P_TEB) : proto;
if (tunnel->parms.collect_md) {
struct ip_tunnel_info *tun_info;
const struct ip_tunnel_key *key;
__be16 flags;
tun_info = skb_tunnel_info(skb);
if (unlikely(!tun_info ||
!(tun_info->mode & IP_TUNNEL_INFO_TX) ||
ip_tunnel_info_af(tun_info) != AF_INET6))
return -EINVAL;
key = &tun_info->key;
memset(fl6, 0, sizeof(*fl6));
fl6->flowi6_proto = IPPROTO_GRE;
fl6->daddr = key->u.ipv6.dst;
fl6->flowlabel = key->label;
fl6->flowi6_uid = sock_net_uid(dev_net(dev), NULL);
dsfield = key->tos;
flags = key->tun_flags & (TUNNEL_CSUM | TUNNEL_KEY);
tunnel->tun_hlen = gre_calc_hlen(flags);
gre_build_header(skb, tunnel->tun_hlen,
flags, protocol,
tunnel_id_to_key32(tun_info->key.tun_id), 0);
} else {
gre_build_header(skb, tunnel->tun_hlen, tunnel->parms.o_flags,
protocol, tunnel->parms.o_key, htonl(tunnel->o_seqno));
protocol, tunnel->parms.o_key,
htonl(tunnel->o_seqno));
}
return ip6_tnl_xmit(skb, dev, dsfield, fl6, encap_limit, pmtu,
NEXTHDR_GRE);
@ -645,13 +702,15 @@ static inline int ip6gre_xmit_ipv4(struct sk_buff *skb, struct net_device *dev)
struct ip6_tnl *t = netdev_priv(dev);
int encap_limit = -1;
struct flowi6 fl6;
__u8 dsfield;
__u8 dsfield = 0;
__u32 mtu;
int err;
memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
prepare_ip6gre_xmit_ipv4(skb, dev, &fl6, &dsfield, &encap_limit);
if (!t->parms.collect_md)
prepare_ip6gre_xmit_ipv4(skb, dev, &fl6,
&dsfield, &encap_limit);
err = gre_handle_offloads(skb, !!(t->parms.o_flags & TUNNEL_CSUM));
if (err)
@ -676,14 +735,15 @@ static inline int ip6gre_xmit_ipv6(struct sk_buff *skb, struct net_device *dev)
struct ipv6hdr *ipv6h = ipv6_hdr(skb);
int encap_limit = -1;
struct flowi6 fl6;
__u8 dsfield;
__u8 dsfield = 0;
__u32 mtu;
int err;
if (ipv6_addr_equal(&t->parms.raddr, &ipv6h->saddr))
return -1;
if (prepare_ip6gre_xmit_ipv6(skb, dev, &fl6, &dsfield, &encap_limit))
if (!t->parms.collect_md &&
prepare_ip6gre_xmit_ipv6(skb, dev, &fl6, &dsfield, &encap_limit))
return -1;
if (gre_handle_offloads(skb, !!(t->parms.o_flags & TUNNEL_CSUM)))
@ -731,6 +791,7 @@ static int ip6gre_xmit_other(struct sk_buff *skb, struct net_device *dev)
if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
encap_limit = t->parms.encap_limit;
if (!t->parms.collect_md)
memcpy(&fl6, &t->fl.u.ip6, sizeof(fl6));
err = gre_handle_offloads(skb, !!(t->parms.o_flags & TUNNEL_CSUM));
@ -1201,6 +1262,11 @@ static int ip6gre_tunnel_init_common(struct net_device *dev)
if (!(tunnel->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
dev->mtu -= 8;
if (tunnel->parms.collect_md) {
dev->features |= NETIF_F_NETNS_LOCAL;
netif_keep_dst(dev);
}
return 0;
}
@ -1215,6 +1281,9 @@ static int ip6gre_tunnel_init(struct net_device *dev)
tunnel = netdev_priv(dev);
if (tunnel->parms.collect_md)
return 0;
memcpy(dev->dev_addr, &tunnel->parms.laddr, sizeof(struct in6_addr));
memcpy(dev->broadcast, &tunnel->parms.raddr, sizeof(struct in6_addr));
@ -1464,6 +1533,9 @@ static void ip6gre_netlink_parms(struct nlattr *data[],
if (data[IFLA_GRE_ERSPAN_INDEX])
parms->index = nla_get_u32(data[IFLA_GRE_ERSPAN_INDEX]);
if (data[IFLA_GRE_COLLECT_METADATA])
parms->collect_md = true;
}
static int ip6gre_tap_init(struct net_device *dev)
@ -1622,8 +1694,13 @@ static int ip6gre_newlink(struct net *src_net, struct net_device *dev,
ip6gre_netlink_parms(data, &nt->parms);
if (nt->parms.collect_md) {
if (rtnl_dereference(ign->collect_md_tun))
return -EEXIST;
} else {
if (ip6gre_tunnel_find(net, &nt->parms, dev->type))
return -EEXIST;
}
if (dev->type == ARPHRD_ETHER && !tb[IFLA_ADDRESS])
eth_hw_addr_random(dev);
@ -1742,6 +1819,8 @@ static size_t ip6gre_get_size(const struct net_device *dev)
nla_total_size(2) +
/* IFLA_GRE_ENCAP_DPORT */
nla_total_size(2) +
/* IFLA_GRE_COLLECT_METADATA */
nla_total_size(0) +
/* IFLA_GRE_FWMARK */
nla_total_size(4) +
/* IFLA_GRE_ERSPAN_INDEX */
@ -1781,6 +1860,11 @@ static int ip6gre_fill_info(struct sk_buff *skb, const struct net_device *dev)
t->encap.flags))
goto nla_put_failure;
if (p->collect_md) {
if (nla_put_flag(skb, IFLA_GRE_COLLECT_METADATA))
goto nla_put_failure;
}
return 0;
nla_put_failure:
@ -1803,6 +1887,7 @@ static const struct nla_policy ip6gre_policy[IFLA_GRE_MAX + 1] = {
[IFLA_GRE_ENCAP_FLAGS] = { .type = NLA_U16 },
[IFLA_GRE_ENCAP_SPORT] = { .type = NLA_U16 },
[IFLA_GRE_ENCAP_DPORT] = { .type = NLA_U16 },
[IFLA_GRE_COLLECT_METADATA] = { .type = NLA_FLAG },
[IFLA_GRE_FWMARK] = { .type = NLA_U32 },
[IFLA_GRE_ERSPAN_INDEX] = { .type = NLA_U32 },
};

View File

@ -861,7 +861,7 @@ int ip6_tnl_rcv(struct ip6_tnl *t, struct sk_buff *skb,
struct metadata_dst *tun_dst,
bool log_ecn_err)
{
return __ip6_tnl_rcv(t, skb, tpi, NULL, ip6ip6_dscp_ecn_decapsulate,
return __ip6_tnl_rcv(t, skb, tpi, tun_dst, ip6ip6_dscp_ecn_decapsulate,
log_ecn_err);
}
EXPORT_SYMBOL(ip6_tnl_rcv);
@ -979,6 +979,9 @@ int ip6_tnl_xmit_ctl(struct ip6_tnl *t,
int ret = 0;
struct net *net = t->net;
if (t->parms.collect_md)
return 1;
if ((p->flags & IP6_TNL_F_CAP_XMIT) ||
((p->flags & IP6_TNL_F_CAP_PER_PACKET) &&
(ip6_tnl_get_cap(t, laddr, raddr) & IP6_TNL_F_CAP_XMIT))) {