[PATCH net-next 5/5] vxlan: use generic function for tunnel IPv6 route lookup

Beniamino Galvani
2023-10-20T11:56:09Z

The route lookup can be done now via generic function
udp_tunnel6_dst_lookup() to replace the custom implementation in
vxlan6_get_route().

This is similar to what already done for IPv4 in commit 6f19b2c136d9
("vxlan: use generic function for tunnel IPv4 route lookup").

Suggested-by: Guillaume Nault <gnault@redhat.com>
Signed-off-by: Beniamino Galvani <b.galvani@gmail.com>
---
drivers/net/vxlan/vxlan_core.c | 136 ++++++++-------------------------
1 file changed, 30 insertions(+), 106 deletions(-)

diff --git a/drivers/net/vxlan/vxlan_core.c b/drivers/net/vxlan/vxlan_core.c
index 6f7d45e3cfa2..7b526ae16ed0 100644
--- a/drivers/net/vxlan/vxlan_core.c
+++ b/drivers/net/vxlan/vxlan_core.c
@@ -2215,63 +2215,6 @@ static int vxlan_build_skb(struct sk_buff *skb, struct dst_entry *dst,
return 0;
}

-#if IS_ENABLED(CONFIG_IPV6)
-static struct dst_entry *vxlan6_get_route(struct vxlan_dev *vxlan,
- struct net_device *dev,
- struct vxlan_sock *sock6,
- struct sk_buff *skb, int oif, u8 tos,
- __be32 label,
- const struct in6_addr *daddr,
- struct in6_addr *saddr,
- __be16 dport, __be16 sport,
- struct dst_cache *dst_cache,
- const struct ip_tunnel_info *info)
-{
- bool use_cache = ip_tunnel_dst_cache_usable(skb, info);
- struct dst_entry *ndst;
- struct flowi6 fl6;
-
- if (!sock6)
- return ERR_PTR(-EIO);
-
- if (tos && !info)
- use_cache = false;
- if (use_cache) {
- ndst = dst_cache_get_ip6(dst_cache, saddr);
- if (ndst)
- return ndst;
- }
-
- memset(&fl6, 0, sizeof(fl6));
- fl6.flowi6_oif = oif;
- fl6.daddr = *daddr;
- fl6.saddr = *saddr;
- fl6.flowlabel = ip6_make_flowinfo(tos, label);
- fl6.flowi6_mark = skb->mark;
- fl6.flowi6_proto = IPPROTO_UDP;
- fl6.fl6_dport = dport;
- fl6.fl6_sport = sport;
-
- ndst = ipv6_stub->ipv6_dst_lookup_flow(vxlan->net, sock6->sock->sk,
- &fl6, NULL);
- if (IS_ERR(ndst)) {
- netdev_dbg(dev, "no route to %pI6\n", daddr);
- return ERR_PTR(-ENETUNREACH);
- }
-
- if (unlikely(ndst->dev == dev)) {
- netdev_dbg(dev, "circular route to %pI6\n", daddr);
- dst_release(ndst);
- return ERR_PTR(-ELOOP);
- }
-
- *saddr = fl6.saddr;
- if (use_cache)
- dst_cache_set_ip6(dst_cache, ndst, saddr);
- return ndst;
-}
-#endif
-
/* Bypass encapsulation if the destination is local */
static void vxlan_encap_bypass(struct sk_buff *skb, struct vxlan_dev *src_vxlan,
struct vxlan_dev *dst_vxlan, __be32 vni,
@@ -2325,7 +2268,7 @@ static void vxlan_encap_bypass(struct sk_buff *skb, struct vxlan_dev *src_vxlan,

static int encap_bypass_if_local(struct sk_buff *skb, struct net_device *dev,
struct vxlan_dev *vxlan,
- union vxlan_addr *daddr,
+ int addr_family,
__be16 dst_port, int dst_ifindex, __be32 vni,
struct dst_entry *dst,
u32 rt_flags)
@@ -2345,7 +2288,7 @@ static int encap_bypass_if_local(struct sk_buff *skb, struct net_device *dev,

dst_release(dst);
dst_vxlan = vxlan_find_vni(vxlan->net, dst_ifindex, vni,
- daddr->sa.sa_family, dst_port,
+ addr_family, dst_port,
vxlan->cfg.flags);
if (!dst_vxlan) {
dev->stats.tx_errors++;
@@ -2371,13 +2314,12 @@ void vxlan_xmit_one(struct sk_buff *skb, struct net_device *dev,
struct ip_tunnel_key key;
struct vxlan_dev *vxlan = netdev_priv(dev);
const struct iphdr *old_iph = ip_hdr(skb);
- union vxlan_addr *dst;
- union vxlan_addr remote_ip;
struct vxlan_metadata _md;
struct vxlan_metadata *md = &_md;
unsigned int pkt_len = skb->len;
__be16 src_port = 0, dst_port;
struct dst_entry *ndst = NULL;
+ int addr_family;
__u8 tos, ttl;
int ifindex;
int err;
@@ -2386,20 +2328,15 @@ void vxlan_xmit_one(struct sk_buff *skb, struct net_device *dev,
bool udp_sum = false;
bool xnet = !net_eq(vxlan->net, dev_net(vxlan->dev));
__be32 vni = 0;
-#if IS_ENABLED(CONFIG_IPV6)
- union vxlan_addr local_ip;
- __be32 label;
-#endif

info = skb_tunnel_info(skb);
use_cache = ip_tunnel_dst_cache_usable(skb, info);

if (rdst) {
- dst = &rdst->remote_ip;
memset(&key, 0, sizeof(key));
pkey = &key;

- if (vxlan_addr_any(dst)) {
+ if (vxlan_addr_any(&rdst->remote_ip)) {
if (did_rsc) {
/* short-circuited back to local bridge */
vxlan_encap_bypass(skb, vxlan, vxlan,
@@ -2409,11 +2346,12 @@ void vxlan_xmit_one(struct sk_buff *skb, struct net_device *dev,
goto drop;
}

+ addr_family = vxlan->cfg.saddr.sa.sa_family;
dst_port = rdst->remote_port ? rdst->remote_port : vxlan->cfg.dst_port;
vni = (rdst->remote_vni) ? : default_vni;
ifindex = rdst->remote_ifindex;

- if (dst->sa.sa_family == AF_INET) {
+ if (addr_family == AF_INET) {
key.u.ipv4.src = vxlan->cfg.saddr.sin.sin_addr.s_addr;
key.u.ipv4.dst = rdst->remote_ip.sin.sin_addr.s_addr;
} else {
@@ -2427,23 +2365,21 @@ void vxlan_xmit_one(struct sk_buff *skb, struct net_device *dev,
ttl = ip_tunnel_get_ttl(old_iph, skb);
} else {
ttl = vxlan->cfg.ttl;
- if (!ttl && vxlan_addr_multicast(dst))
+ if (!ttl && vxlan_addr_multicast(&rdst->remote_ip))
ttl = 1;
}
-
tos = vxlan->cfg.tos;
if (tos == 1)
tos = ip_tunnel_get_dsfield(old_iph, skb);
if (tos && !info)
use_cache = false;

- if (dst->sa.sa_family == AF_INET)
+ if (addr_family == AF_INET)
udp_sum = !(flags & VXLAN_F_UDP_ZERO_CSUM_TX);
else
udp_sum = !(flags & VXLAN_F_UDP_ZERO_CSUM6_TX);
#if IS_ENABLED(CONFIG_IPV6)
- local_ip = vxlan->cfg.saddr;
- label = vxlan->cfg.label;
+ key.label = vxlan->cfg.label;
#endif
} else {
if (!info) {
@@ -2451,17 +2387,8 @@ void vxlan_xmit_one(struct sk_buff *skb, struct net_device *dev,
dev->name);
goto drop;
}
- remote_ip.sa.sa_family = ip_tunnel_info_af(info);
- if (remote_ip.sa.sa_family == AF_INET) {
- remote_ip.sin.sin_addr.s_addr = info->key.u.ipv4.dst;
- } else {
- remote_ip.sin6.sin6_addr = info->key.u.ipv6.dst;
-#if IS_ENABLED(CONFIG_IPV6)
- local_ip.sin6.sin6_addr = info->key.u.ipv6.src;
-#endif
- }
- dst = &remote_ip;
pkey = &info->key;
+ addr_family = ip_tunnel_info_af(info);
dst_port = info->key.tp_dst ? : vxlan->cfg.dst_port;
vni = tunnel_id_to_key32(info->key.tun_id);
ifindex = 0;
@@ -2473,16 +2400,13 @@ void vxlan_xmit_one(struct sk_buff *skb, struct net_device *dev,
}
ttl = info->key.ttl;
tos = info->key.tos;
-#if IS_ENABLED(CONFIG_IPV6)
- label = info->key.label;
-#endif
udp_sum = !!(info->key.tun_flags & TUNNEL_CSUM);
}
src_port = udp_flow_src_port(dev_net(dev), skb, vxlan->cfg.port_min,
vxlan->cfg.port_max, true);

rcu_read_lock();
- if (dst->sa.sa_family == AF_INET) {
+ if (addr_family == AF_INET) {
struct vxlan_sock *sock4 = rcu_dereference(vxlan->vn4_sock);
struct rtable *rt;
__be16 df = 0;
@@ -2501,7 +2425,7 @@ void vxlan_xmit_one(struct sk_buff *skb, struct net_device *dev,

if (!info) {
/* Bypass encapsulation if the destination is local */
- err = encap_bypass_if_local(skb, dev, vxlan, dst,
+ err = encap_bypass_if_local(skb, dev, vxlan, AF_INET,
dst_port, ifindex, vni,
&rt->dst, rt->rt_flags);
if (err)
@@ -2555,15 +2479,15 @@ void vxlan_xmit_one(struct sk_buff *skb, struct net_device *dev,
#if IS_ENABLED(CONFIG_IPV6)
} else {
struct vxlan_sock *sock6 = rcu_dereference(vxlan->vn6_sock);
+ struct in6_addr saddr;

if (!ifindex)
ifindex = sock6->sock->sk->sk_bound_dev_if;

- ndst = vxlan6_get_route(vxlan, dev, sock6, skb, ifindex, tos,
- label, &dst->sin6.sin6_addr,
- &local_ip.sin6.sin6_addr,
- dst_port, src_port,
- dst_cache, info);
+ ndst = udp_tunnel6_dst_lookup(skb, dev, vxlan->net, sock6->sock,
+ ifindex, &saddr, pkey,
+ src_port, dst_port, tos,
+ use_cache ? dst_cache : NULL);
if (IS_ERR(ndst)) {
err = PTR_ERR(ndst);
ndst = NULL;
@@ -2573,7 +2497,7 @@ void vxlan_xmit_one(struct sk_buff *skb, struct net_device *dev,
if (!info) {
u32 rt6i_flags = ((struct rt6_info *)ndst)->rt6i_flags;

- err = encap_bypass_if_local(skb, dev, vxlan, dst,
+ err = encap_bypass_if_local(skb, dev, vxlan, AF_INET6,
dst_port, ifindex, vni,
ndst, rt6i_flags);
if (err)
@@ -2588,16 +2512,13 @@ void vxlan_xmit_one(struct sk_buff *skb, struct net_device *dev,
} else if (err) {
if (info) {
struct ip_tunnel_info *unclone;
- struct in6_addr src, dst;

unclone = skb_tunnel_info_unclone(skb);
if (unlikely(!unclone))
goto tx_error;

- src = remote_ip.sin6.sin6_addr;
- dst = local_ip.sin6.sin6_addr;
- unclone->key.u.ipv6.src = src;
- unclone->key.u.ipv6.dst = dst;
+ unclone->key.u.ipv6.src = pkey->u.ipv6.dst;
+ unclone->key.u.ipv6.dst = saddr;
}

vxlan_encap_bypass(skb, vxlan, vxlan, vni, false);
@@ -2614,9 +2535,8 @@ void vxlan_xmit_one(struct sk_buff *skb, struct net_device *dev,
goto tx_error;

udp_tunnel6_xmit_skb(ndst, sock6->sock->sk, skb, dev,
- &local_ip.sin6.sin6_addr,
- &dst->sin6.sin6_addr, tos, ttl,
- label, src_port, dst_port, !udp_sum);
+ &saddr, &pkey->u.ipv6.dst, tos, ttl,
+ pkey->label, src_port, dst_port, !udp_sum);
#endif
}
vxlan_vnifilter_count(vxlan, vni, NULL, VXLAN_VNI_STATS_TX, pkt_len);
@@ -3267,10 +3187,14 @@ static int vxlan_fill_metadata_dst(struct net_device *dev, struct sk_buff *skb)
struct vxlan_sock *sock6 = rcu_dereference(vxlan->vn6_sock);
struct dst_entry *ndst;

- ndst = vxlan6_get_route(vxlan, dev, sock6, skb, 0, info->key.tos,
- info->key.label, &info->key.u.ipv6.dst,
- &info->key.u.ipv6.src, dport, sport,
- &info->dst_cache, info);
+ if (!sock6)
+ return -EIO;
+
+ ndst = udp_tunnel6_dst_lookup(skb, dev, vxlan->net, sock6->sock,
+ 0, &info->key.u.ipv6.src,
+ &info->key,
+ sport, dport, info->key.tos,
+ &info->dst_cache);
if (IS_ERR(ndst))
return PTR_ERR(ndst);
dst_release(ndst);
--
2.40.1