Skip to content

Commit

Permalink
ip6_tunnel: add collect_md mode to IPv6 tunnels
Browse files Browse the repository at this point in the history 
Similar to gre, vxlan, geneve tunnels allow IPIP6 and IP6IP6 tunnels
to operate in 'collect metadata' mode.
Unlike ipv4 code here it's possible to reuse ip6_tnl_xmit() function
for both collect_md and traditional tunnels.
bpf_skb_[gs]et_tunnel_key() helpers and ovs (in the future) are the users.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Thomas Graf <tgraf@suug.ch>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
  • Loading branch information
@4ast @davem330
4ast authored and davem330 committed Sep 17, 2016
1 parent cfc7381 commit 8d79266
Show file tree
Hide file tree
Showing 2 changed files with 134 additions and 45 deletions.
1 change: 1 addition & 0 deletions include/net/ip6_tunnel.h
View file
Original file line number Diff line number Diff line change
Expand Up @@ -23,6 +23,7 @@ struct __ip6_tnl_parm {
__u8 proto; /* tunnel protocol */
__u8 encap_limit; /* encapsulation limit for tunnel */
__u8 hop_limit; /* hop limit for tunnel */
bool collect_md;
__be32 flowinfo; /* traffic class and flowlabel for tunnel */
__u32 flags; /* tunnel flags */
struct in6_addr laddr; /* local tunnel end-point address */
Expand Down
178 changes: 133 additions & 45 deletions net/ipv6/ip6_tunnel.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -57,6 +57,7 @@
#include <net/inet_ecn.h>
#include <net/net_namespace.h>
#include <net/netns/generic.h>
#include <net/dst_metadata.h>

MODULE_AUTHOR("Ville Nuorvala");
MODULE_DESCRIPTION("IPv6 tunneling device");
Expand Down Expand Up @@ -90,6 +91,7 @@ struct ip6_tnl_net {
struct ip6_tnl __rcu *tnls_r_l[IP6_TUNNEL_HASH_SIZE];
struct ip6_tnl __rcu *tnls_wc[1];
struct ip6_tnl __rcu **tnls[2];
struct ip6_tnl __rcu *collect_md_tun;
};

static struct net_device_stats *ip6_get_stats(struct net_device *dev)
Expand Down Expand Up @@ -166,6 +168,10 @@ ip6_tnl_lookup(struct net *net, const struct in6_addr *remote, const struct in6_
return t;
}

t = rcu_dereference(ip6n->collect_md_tun);
if (t)
return t;

t = rcu_dereference(ip6n->tnls_wc[0]);
if (t && (t->dev->flags & IFF_UP))
return t;
Expand Down Expand Up @@ -209,6 +215,8 @@ ip6_tnl_link(struct ip6_tnl_net *ip6n, struct ip6_tnl *t)
{
struct ip6_tnl __rcu **tp = ip6_tnl_bucket(ip6n, &t->parms);

if (t->parms.collect_md)
rcu_assign_pointer(ip6n->collect_md_tun, t);
rcu_assign_pointer(t->next , rtnl_dereference(*tp));
rcu_assign_pointer(*tp, t);
}
Expand All @@ -224,6 +232,9 @@ ip6_tnl_unlink(struct ip6_tnl_net *ip6n, struct ip6_tnl *t)
struct ip6_tnl __rcu **tp;
struct ip6_tnl *iter;

if (t->parms.collect_md)
rcu_assign_pointer(ip6n->collect_md_tun, NULL);

for (tp = ip6_tnl_bucket(ip6n, &t->parms);
(iter = rtnl_dereference(*tp)) != NULL;
tp = &iter->next) {
Expand Down Expand Up @@ -829,6 +840,9 @@ static int __ip6_tnl_rcv(struct ip6_tnl *tunnel, struct sk_buff *skb,

skb_scrub_packet(skb, !net_eq(tunnel->net, dev_net(tunnel->dev)));

if (tun_dst)
skb_dst_set(skb, (struct dst_entry *)tun_dst);

gro_cells_receive(&tunnel->gro_cells, skb);
return 0;

Expand Down Expand Up @@ -865,6 +879,7 @@ static int ipxip6_rcv(struct sk_buff *skb, u8 ipproto,
{
struct ip6_tnl *t;
const struct ipv6hdr *ipv6h = ipv6_hdr(skb);
struct metadata_dst *tun_dst = NULL;
int ret = -1;

rcu_read_lock();
Expand All @@ -881,7 +896,12 @@ static int ipxip6_rcv(struct sk_buff *skb, u8 ipproto,
goto drop;
if (iptunnel_pull_header(skb, 0, tpi->proto, false))
goto drop;
ret = __ip6_tnl_rcv(t, skb, tpi, NULL, dscp_ecn_decapsulate,
if (t->parms.collect_md) {
tun_dst = ipv6_tun_rx_dst(skb, 0, 0, 0);
if (!tun_dst)
return 0;
}
ret = __ip6_tnl_rcv(t, skb, tpi, tun_dst, dscp_ecn_decapsulate,
log_ecn_error);
}

Expand Down Expand Up @@ -1012,8 +1032,16 @@ int ip6_tnl_xmit(struct sk_buff *skb, struct net_device *dev, __u8 dsfield,
int mtu;
unsigned int psh_hlen = sizeof(struct ipv6hdr) + t->encap_hlen;
unsigned int max_headroom = psh_hlen;
u8 hop_limit;
int err = -1;

if (t->parms.collect_md) {
hop_limit = skb_tunnel_info(skb)->key.ttl;
goto route_lookup;
} else {
hop_limit = t->parms.hop_limit;
}

/* NBMA tunnel */
if (ipv6_addr_any(&t->parms.raddr)) {
struct in6_addr *addr6;
Expand Down Expand Up @@ -1043,6 +1071,7 @@ int ip6_tnl_xmit(struct sk_buff *skb, struct net_device *dev, __u8 dsfield,
goto tx_err_link_failure;

if (!dst) {
route_lookup:
dst = ip6_route_output(net, NULL, fl6);

if (dst->error)
Expand All @@ -1053,6 +1082,10 @@ int ip6_tnl_xmit(struct sk_buff *skb, struct net_device *dev, __u8 dsfield,
dst = NULL;
goto tx_err_link_failure;
}
if (t->parms.collect_md &&
ipv6_dev_get_saddr(net, ip6_dst_idev(dst)->dev,
&fl6->daddr, 0, &fl6->saddr))
goto tx_err_link_failure;
ndst = dst;
}

Expand All @@ -1071,7 +1104,7 @@ int ip6_tnl_xmit(struct sk_buff *skb, struct net_device *dev, __u8 dsfield,
}
if (mtu < IPV6_MIN_MTU)
mtu = IPV6_MIN_MTU;
if (skb_dst(skb))
if (skb_dst(skb) && !t->parms.collect_md)
skb_dst(skb)->ops->update_pmtu(skb_dst(skb), NULL, skb, mtu);
if (skb->len > mtu && !skb_is_gso(skb)) {
*pmtu = mtu;
Expand Down Expand Up @@ -1111,8 +1144,13 @@ int ip6_tnl_xmit(struct sk_buff *skb, struct net_device *dev, __u8 dsfield,
skb = new_skb;
}

if (!fl6->flowi6_mark && ndst)
dst_cache_set_ip6(&t->dst_cache, ndst, &fl6->saddr);
if (t->parms.collect_md) {
if (t->encap.type != TUNNEL_ENCAP_NONE)
goto tx_err_dst_release;
} else {
if (!fl6->flowi6_mark && ndst)
dst_cache_set_ip6(&t->dst_cache, ndst, &fl6->saddr);
}
skb_dst_set(skb, dst);

if (encap_limit >= 0) {
Expand All @@ -1137,7 +1175,7 @@ int ip6_tnl_xmit(struct sk_buff *skb, struct net_device *dev, __u8 dsfield,
ipv6h = ipv6_hdr(skb);
ip6_flow_hdr(ipv6h, INET_ECN_encapsulate(0, dsfield),
ip6_make_flowlabel(net, skb, fl6->flowlabel, true, fl6));
ipv6h->hop_limit = t->parms.hop_limit;
ipv6h->hop_limit = hop_limit;
ipv6h->nexthdr = proto;
ipv6h->saddr = fl6->saddr;
ipv6h->daddr = fl6->daddr;
Expand Down Expand Up @@ -1170,19 +1208,34 @@ ip4ip6_tnl_xmit(struct sk_buff *skb, struct net_device *dev)
if (tproto != IPPROTO_IPIP && tproto != 0)
return -1;

if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
encap_limit = t->parms.encap_limit;
dsfield = ipv4_get_dsfield(iph);

memcpy(&fl6, &t->fl.u.ip6, sizeof(fl6));
fl6.flowi6_proto = IPPROTO_IPIP;
if (t->parms.collect_md) {
struct ip_tunnel_info *tun_info;
const struct ip_tunnel_key *key;

dsfield = ipv4_get_dsfield(iph);
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 -1;
key = &tun_info->key;
memset(&fl6, 0, sizeof(fl6));
fl6.flowi6_proto = IPPROTO_IPIP;
fl6.daddr = key->u.ipv6.dst;
fl6.flowlabel = key->label;
} else {
if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
encap_limit = t->parms.encap_limit;

if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS)
fl6.flowlabel |= htonl((__u32)iph->tos << IPV6_TCLASS_SHIFT)
& IPV6_TCLASS_MASK;
if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK)
fl6.flowi6_mark = skb->mark;
memcpy(&fl6, &t->fl.u.ip6, sizeof(fl6));
fl6.flowi6_proto = IPPROTO_IPIP;

if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS)
fl6.flowlabel |= htonl((__u32)iph->tos << IPV6_TCLASS_SHIFT)
& IPV6_TCLASS_MASK;
if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK)
fl6.flowi6_mark = skb->mark;
}

if (iptunnel_handle_offloads(skb, SKB_GSO_IPXIP6))
return -1;
Expand Down Expand Up @@ -1220,29 +1273,47 @@ ip6ip6_tnl_xmit(struct sk_buff *skb, struct net_device *dev)
ip6_tnl_addr_conflict(t, ipv6h))
return -1;

offset = ip6_tnl_parse_tlv_enc_lim(skb, skb_network_header(skb));
if (offset > 0) {
struct ipv6_tlv_tnl_enc_lim *tel;
tel = (struct ipv6_tlv_tnl_enc_lim *)&skb_network_header(skb)[offset];
if (tel->encap_limit == 0) {
icmpv6_send(skb, ICMPV6_PARAMPROB,
ICMPV6_HDR_FIELD, offset + 2);
dsfield = ipv6_get_dsfield(ipv6h);

if (t->parms.collect_md) {
struct ip_tunnel_info *tun_info;
const struct ip_tunnel_key *key;

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 -1;
key = &tun_info->key;
memset(&fl6, 0, sizeof(fl6));
fl6.flowi6_proto = IPPROTO_IPV6;
fl6.daddr = key->u.ipv6.dst;
fl6.flowlabel = key->label;
} else {
offset = ip6_tnl_parse_tlv_enc_lim(skb, skb_network_header(skb));
if (offset > 0) {
struct ipv6_tlv_tnl_enc_lim *tel;

tel = (void *)&skb_network_header(skb)[offset];
if (tel->encap_limit == 0) {
icmpv6_send(skb, ICMPV6_PARAMPROB,
ICMPV6_HDR_FIELD, offset + 2);
return -1;
}
encap_limit = tel->encap_limit - 1;
} else if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) {
encap_limit = t->parms.encap_limit;
}
encap_limit = tel->encap_limit - 1;
} else if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
encap_limit = t->parms.encap_limit;

memcpy(&fl6, &t->fl.u.ip6, sizeof(fl6));
fl6.flowi6_proto = IPPROTO_IPV6;
memcpy(&fl6, &t->fl.u.ip6, sizeof(fl6));
fl6.flowi6_proto = IPPROTO_IPV6;

dsfield = ipv6_get_dsfield(ipv6h);
if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS)
fl6.flowlabel |= (*(__be32 *) ipv6h & IPV6_TCLASS_MASK);
if (t->parms.flags & IP6_TNL_F_USE_ORIG_FLOWLABEL)
fl6.flowlabel |= ip6_flowlabel(ipv6h);
if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK)
fl6.flowi6_mark = skb->mark;
if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS)
fl6.flowlabel |= (*(__be32 *)ipv6h & IPV6_TCLASS_MASK);
if (t->parms.flags & IP6_TNL_F_USE_ORIG_FLOWLABEL)
fl6.flowlabel |= ip6_flowlabel(ipv6h);
if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK)
fl6.flowi6_mark = skb->mark;
}

if (iptunnel_handle_offloads(skb, SKB_GSO_IPXIP6))
return -1;
Expand Down Expand Up @@ -1741,6 +1812,10 @@ static int ip6_tnl_dev_init(struct net_device *dev)
if (err)
return err;
ip6_tnl_link_config(t);
if (t->parms.collect_md) {
dev->features |= NETIF_F_NETNS_LOCAL;
netif_keep_dst(dev);
}
return 0;
}

Expand Down Expand Up @@ -1811,6 +1886,9 @@ static void ip6_tnl_netlink_parms(struct nlattr *data[],

if (data[IFLA_IPTUN_PROTO])
parms->proto = nla_get_u8(data[IFLA_IPTUN_PROTO]);

if (data[IFLA_IPTUN_COLLECT_METADATA])
parms->collect_md = true;
}

static bool ip6_tnl_netlink_encap_parms(struct nlattr *data[],
Expand Down Expand Up @@ -1850,6 +1928,7 @@ static int ip6_tnl_newlink(struct net *src_net, struct net_device *dev,
struct nlattr *tb[], struct nlattr *data[])
{
struct net *net = dev_net(dev);
struct ip6_tnl_net *ip6n = net_generic(net, ip6_tnl_net_id);
struct ip6_tnl *nt, *t;
struct ip_tunnel_encap ipencap;

Expand All @@ -1864,9 +1943,14 @@ static int ip6_tnl_newlink(struct net *src_net, struct net_device *dev,

ip6_tnl_netlink_parms(data, &nt->parms);

t = ip6_tnl_locate(net, &nt->parms, 0);
if (!IS_ERR(t))
return -EEXIST;
if (nt->parms.collect_md) {
if (rtnl_dereference(ip6n->collect_md_tun))
return -EEXIST;
} else {
t = ip6_tnl_locate(net, &nt->parms, 0);
if (!IS_ERR(t))
return -EEXIST;
}

return ip6_tnl_create2(dev);
}
Expand All @@ -1890,6 +1974,8 @@ static int ip6_tnl_changelink(struct net_device *dev, struct nlattr *tb[],
return err;
}
ip6_tnl_netlink_parms(data, &p);
if (p.collect_md)
return -EINVAL;

t = ip6_tnl_locate(net, &p, 0);
if (!IS_ERR(t)) {
Expand Down Expand Up @@ -1937,6 +2023,8 @@ static size_t ip6_tnl_get_size(const struct net_device *dev)
nla_total_size(2) +
/* IFLA_IPTUN_ENCAP_DPORT */
nla_total_size(2) +
/* IFLA_IPTUN_COLLECT_METADATA */
nla_total_size(0) +
0;
}

Expand All @@ -1955,16 +2043,15 @@ static int ip6_tnl_fill_info(struct sk_buff *skb, const struct net_device *dev)
nla_put_u8(skb, IFLA_IPTUN_PROTO, parm->proto))
goto nla_put_failure;

if (nla_put_u16(skb, IFLA_IPTUN_ENCAP_TYPE,
tunnel->encap.type) ||
nla_put_be16(skb, IFLA_IPTUN_ENCAP_SPORT,
tunnel->encap.sport) ||
nla_put_be16(skb, IFLA_IPTUN_ENCAP_DPORT,
tunnel->encap.dport) ||
nla_put_u16(skb, IFLA_IPTUN_ENCAP_FLAGS,
tunnel->encap.flags))
if (nla_put_u16(skb, IFLA_IPTUN_ENCAP_TYPE, tunnel->encap.type) ||
nla_put_be16(skb, IFLA_IPTUN_ENCAP_SPORT, tunnel->encap.sport) ||
nla_put_be16(skb, IFLA_IPTUN_ENCAP_DPORT, tunnel->encap.dport) ||
nla_put_u16(skb, IFLA_IPTUN_ENCAP_FLAGS, tunnel->encap.flags))
goto nla_put_failure;

if (parm->collect_md)
if (nla_put_flag(skb, IFLA_IPTUN_COLLECT_METADATA))
goto nla_put_failure;
return 0;

nla_put_failure:
Expand Down Expand Up @@ -1992,6 +2079,7 @@ static const struct nla_policy ip6_tnl_policy[IFLA_IPTUN_MAX + 1] = {
[IFLA_IPTUN_ENCAP_FLAGS] = { .type = NLA_U16 },
[IFLA_IPTUN_ENCAP_SPORT] = { .type = NLA_U16 },
[IFLA_IPTUN_ENCAP_DPORT] = { .type = NLA_U16 },
[IFLA_IPTUN_COLLECT_METADATA] = { .type = NLA_FLAG },
};

static struct rtnl_link_ops ip6_link_ops __read_mostly = {
Expand Down

0 comments on commit 8d79266

Please sign in to comment.