As link-local addresses are only valid for a single interface, we can allow
to use the same VNI for multiple independent VXLANs, as long as the used
interfaces are distinct. This way, VXLANs can always be used as a drop-in
replacement for VLANs with greater ID space.
This also extends VNI lookup to respect the ifindex when link-local IPv6
addresses are used, so using the same VNI on multiple interfaces can
actually work.
Signed-off-by: Matthias Schiffer <mschif...@universe-factory.net>
---
drivers/net/vxlan.c | 88 ++++++++++++++++++++++++++++++++++++-----------------
1 file changed, 60 insertions(+), 28 deletions(-)
diff --git a/drivers/net/vxlan.c b/drivers/net/vxlan.c
index 4c0ef8bbad71..9cd6f6b92cf4 100644
--- a/drivers/net/vxlan.c
+++ b/drivers/net/vxlan.c
@@ -224,7 +224,8 @@ static struct vxlan_sock *vxlan_find_sock(struct net *net,
sa_family_t family,
return NULL;
}
-static struct vxlan_dev *vxlan_vs_find_vni(struct vxlan_sock *vs, __be32 vni)
+static struct vxlan_dev *vxlan_vs_find_vni(struct vxlan_sock *vs, int ifindex,
+ __be32 vni)
{
struct vxlan_dev *vxlan;
@@ -233,17 +234,30 @@ static struct vxlan_dev *vxlan_vs_find_vni(struct
vxlan_sock *vs, __be32 vni)
vni = 0;
hlist_for_each_entry_rcu(vxlan, vni_head(vs, vni), hlist) {
- if (vxlan->default_dst.remote_vni == vni)
- return vxlan;
+ if (vxlan->default_dst.remote_vni != vni)
+ continue;
+
+ if (IS_ENABLED(CONFIG_IPV6)) {
+ const struct vxlan_config *cfg = &vxlan->cfg;
+
+ if (cfg->remote_ifindex != 0 &&
+ cfg->remote_ifindex != ifindex &&
+ cfg->saddr.sa.sa_family == AF_INET6 &&
+ (ipv6_addr_type(&cfg->saddr.sin6.sin6_addr) &
+ IPV6_ADDR_LINKLOCAL))
+ continue;
+ }
+
+ return vxlan;
}
return NULL;
}
/* Look up VNI in a per net namespace table */
-static struct vxlan_dev *vxlan_find_vni(struct net *net, __be32 vni,
- sa_family_t family, __be16 port,
- u32 flags)
+static struct vxlan_dev *vxlan_find_vni(struct net *net, int ifindex,
+ __be32 vni, sa_family_t family,
+ __be16 port, u32 flags)
{
struct vxlan_sock *vs;
@@ -251,7 +265,7 @@ static struct vxlan_dev *vxlan_find_vni(struct net *net,
__be32 vni,
if (!vs)
return NULL;
- return vxlan_vs_find_vni(vs, vni);
+ return vxlan_vs_find_vni(vs, ifindex, vni);
}
/* Fill in neighbour message in skbuff. */
@@ -1342,7 +1356,7 @@ static int vxlan_rcv(struct sock *sk, struct sk_buff *skb)
vni = vxlan_vni(vxlan_hdr(skb)->vx_vni);
- vxlan = vxlan_vs_find_vni(vs, vni);
+ vxlan = vxlan_vs_find_vni(vs, skb->dev->ifindex, vni);
if (!vxlan)
goto drop;
@@ -2002,8 +2016,10 @@ 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,
- __be16 dst_port, __be32 vni, struct dst_entry
*dst,
+ struct vxlan_dev *vxlan,
+ union vxlan_addr *daddr,
+ __be16 dst_port, int dst_ifindex, __be32 vni,
+ struct dst_entry *dst,
u32 rt_flags)
{
#if IS_ENABLED(CONFIG_IPV6)
@@ -2019,7 +2035,7 @@ static int encap_bypass_if_local(struct sk_buff *skb,
struct net_device *dev,
struct vxlan_dev *dst_vxlan;
dst_release(dst);
- dst_vxlan = vxlan_find_vni(vxlan->net, vni,
+ dst_vxlan = vxlan_find_vni(vxlan->net, dst_ifindex, vni,
daddr->sa.sa_family, dst_port,
vxlan->flags);
if (!dst_vxlan) {
@@ -2051,6 +2067,7 @@ static void vxlan_xmit_one(struct sk_buff *skb, struct
net_device *dev,
struct dst_entry *ndst = NULL;
__be32 vni, label;
__u8 tos, ttl;
+ int ifindex;
int err;
u32 flags = vxlan->flags;
bool udp_sum = false;
@@ -2071,6 +2088,7 @@ static void vxlan_xmit_one(struct sk_buff *skb, struct
net_device *dev,
dst_port = rdst->remote_port ? rdst->remote_port :
vxlan->cfg.dst_port;
vni = (rdst->remote_vni) ? : default_vni;
+ ifindex = rdst->remote_ifindex;
local_ip = vxlan->cfg.saddr;
dst_cache = &rdst->dst_cache;
md->gbp = skb->mark;
@@ -2104,6 +2122,7 @@ static void vxlan_xmit_one(struct sk_buff *skb, struct
net_device *dev,
dst = &remote_ip;
dst_port = info->key.tp_dst ? : vxlan->cfg.dst_port;
vni = tunnel_id_to_key32(info->key.tun_id);
+ ifindex = 0;
dst_cache = &info->dst_cache;
if (info->options_len)
md = ip_tunnel_info_opts(info);
@@ -2121,8 +2140,7 @@ static void vxlan_xmit_one(struct sk_buff *skb, struct
net_device *dev,
struct rtable *rt;
__be16 df = 0;
- rt = vxlan_get_route(vxlan, dev, sock4, skb,
- rdst ? rdst->remote_ifindex : 0, tos,
+ rt = vxlan_get_route(vxlan, dev, sock4, skb, ifindex, tos,
dst->sin.sin_addr.s_addr,
&local_ip.sin.sin_addr.s_addr,
dst_port, src_port,
@@ -2135,8 +2153,8 @@ static void vxlan_xmit_one(struct sk_buff *skb, struct
net_device *dev,
/* Bypass encapsulation if the destination is local */
if (!info) {
err = encap_bypass_if_local(skb, dev, vxlan, dst,
- dst_port, vni, &rt->dst,
- rt->rt_flags);
+ dst_port, ifindex, vni,
+ &rt->dst, rt->rt_flags);
if (err)
goto out_unlock;
} else if (info->key.tun_flags & TUNNEL_DONT_FRAGMENT) {
@@ -2158,8 +2176,7 @@ static void vxlan_xmit_one(struct sk_buff *skb, struct
net_device *dev,
} else {
struct vxlan_sock *sock6 = rcu_dereference(vxlan->vn6_sock);
- ndst = vxlan6_get_route(vxlan, dev, sock6, skb,
- rdst ? rdst->remote_ifindex : 0, tos,
+ ndst = vxlan6_get_route(vxlan, dev, sock6, skb, ifindex, tos,
label, &dst->sin6.sin6_addr,
&local_ip.sin6.sin6_addr,
dst_port, src_port,
@@ -2174,8 +2191,8 @@ static void vxlan_xmit_one(struct sk_buff *skb, struct
net_device *dev,
u32 rt6i_flags = ((struct rt6_info *)ndst)->rt6i_flags;
err = encap_bypass_if_local(skb, dev, vxlan, dst,
- dst_port, vni, ndst,
- rt6i_flags);
+ dst_port, ifindex, vni,
+ ndst, rt6i_flags);
if (err)
goto out_unlock;
}
@@ -2984,15 +3001,30 @@ static int vxlan_dev_configure(struct net *src_net,
struct net_device *dev,
return 0;
list_for_each_entry(tmp, &vn->vxlan_list, next) {
- if (tmp->cfg.vni == conf->vni &&
- (tmp->default_dst.remote_ip.sa.sa_family == AF_INET6 ||
- tmp->cfg.saddr.sa.sa_family == AF_INET6) == use_ipv6 &&
- tmp->cfg.dst_port == vxlan->cfg.dst_port &&
- (tmp->flags & VXLAN_F_RCV_FLAGS) ==
- (vxlan->flags & VXLAN_F_RCV_FLAGS)) {
- pr_info("duplicate VNI %u\n", be32_to_cpu(conf->vni));
- return -EEXIST;
- }
+ if (tmp->cfg.vni != conf->vni)
+ continue;
+ if ((tmp->default_dst.remote_ip.sa.sa_family == AF_INET6 ||
+ tmp->cfg.saddr.sa.sa_family == AF_INET6) != use_ipv6)
+ continue;
+ if (tmp->cfg.dst_port != vxlan->cfg.dst_port)
+ continue;
+ if ((tmp->flags & VXLAN_F_RCV_FLAGS) !=
+ (vxlan->flags & VXLAN_F_RCV_FLAGS))
+ continue;
+
+#if IS_ENABLED(CONFIG_IPV6)
+ if (conf->remote_ifindex != tmp->cfg.remote_ifindex &&
+ conf->saddr.sa.sa_family == AF_INET6 &&
+ tmp->cfg.saddr.sa.sa_family == AF_INET6 &&
+ (ipv6_addr_type(&conf->saddr.sin6.sin6_addr) &
+ IPV6_ADDR_LINKLOCAL) &&
+ (ipv6_addr_type(&tmp->cfg.saddr.sin6.sin6_addr) &
+ IPV6_ADDR_LINKLOCAL))
+ continue;
+#endif
+
+ pr_info("duplicate VNI %u\n", be32_to_cpu(conf->vni));
+ return -EEXIST;
}
return 0;
--
2.12.0
