2023-10-20 11:56:12

by Beniamino Galvani

[permalink] [raw]
Subject: [PATCH net-next 3/5] ipv6: add new arguments to udp_tunnel6_dst_lookup()

We want to make the function more generic so that it can be used by
other UDP tunnel implementations such as geneve and vxlan. To do that,
add the following arguments:

- source and destination UDP port;
- ifindex of the output interface, needed by vxlan;
- the tos, because in some cases it is not taken from struct
ip_tunnel_info (for example, when it's inherited from the inner
packet);
- the dst cache, because not all tunnel types (e.g. vxlan) want to
use the one from struct ip_tunnel_info.

With these parameters, the function no longer needs the full struct
ip_tunnel_info as argument and we can pass only the relevant part of
it (struct ip_tunnel_key).

This is similar to what already done for IPv4 in commit 72fc68c6356b
("ipv4: add new arguments to udp_tunnel_dst_lookup()").

Suggested-by: Guillaume Nault <[email protected]>
Signed-off-by: Beniamino Galvani <[email protected]>
---
drivers/net/bareudp.c | 10 +++++++---
include/net/udp_tunnel.h | 7 ++++---
net/ipv6/ip6_udp_tunnel.c | 33 ++++++++++++++++++---------------
3 files changed, 29 insertions(+), 21 deletions(-)

diff --git a/drivers/net/bareudp.c b/drivers/net/bareudp.c
index 9eb5e11c09b4..9c11a0d0273b 100644
--- a/drivers/net/bareudp.c
+++ b/drivers/net/bareudp.c
@@ -371,8 +371,10 @@ static int bareudp6_xmit_skb(struct sk_buff *skb, struct net_device *dev,
if (!sock)
return -ESHUTDOWN;

- dst = udp_tunnel6_dst_lookup(skb, dev, bareudp->net, sock, &saddr, info,
- use_cache);
+ dst = udp_tunnel6_dst_lookup(skb, dev, bareudp->net, sock, 0, &saddr,
+ key, 0, 0, key->tos,
+ use_cache ?
+ (struct dst_cache *) &info->dst_cache : NULL);
if (IS_ERR(dst))
return PTR_ERR(dst);

@@ -499,7 +501,9 @@ static int bareudp_fill_metadata_dst(struct net_device *dev,
struct socket *sock = rcu_dereference(bareudp->sock);

dst = udp_tunnel6_dst_lookup(skb, dev, bareudp->net, sock,
- &saddr, info, use_cache);
+ 0, &saddr, &info->key,
+ 0, 0, info->key.tos,
+ use_cache ? &info->dst_cache : NULL);
if (IS_ERR(dst))
return PTR_ERR(dst);

diff --git a/include/net/udp_tunnel.h b/include/net/udp_tunnel.h
index 583867643bd1..d716214fe03d 100644
--- a/include/net/udp_tunnel.h
+++ b/include/net/udp_tunnel.h
@@ -172,10 +172,11 @@ struct rtable *udp_tunnel_dst_lookup(struct sk_buff *skb,
struct dst_entry *udp_tunnel6_dst_lookup(struct sk_buff *skb,
struct net_device *dev,
struct net *net,
- struct socket *sock,
+ struct socket *sock, int oif,
struct in6_addr *saddr,
- const struct ip_tunnel_info *info,
- bool use_cache);
+ const struct ip_tunnel_key *key,
+ __be16 sport, __be16 dport, u8 dsfield,
+ struct dst_cache *dst_cache);

struct metadata_dst *udp_tun_rx_dst(struct sk_buff *skb, unsigned short family,
__be16 flags, __be64 tunnel_id,
diff --git a/net/ipv6/ip6_udp_tunnel.c b/net/ipv6/ip6_udp_tunnel.c
index b9c906518ce2..a7bf0327b380 100644
--- a/net/ipv6/ip6_udp_tunnel.c
+++ b/net/ipv6/ip6_udp_tunnel.c
@@ -119,9 +119,13 @@ EXPORT_SYMBOL_GPL(udp_tunnel6_xmit_skb);
* @dev: Tunnel device
* @net: Network namespace of tunnel device
* @sock: Socket which provides route info
+ * @oif: Index of the output interface
* @saddr: Memory to store the src ip address
- * @info: Tunnel information
- * @use_cache: Flag to enable cache usage
+ * @key: Tunnel information
+ * @sport: UDP source port
+ * @dport: UDP destination port
+ * @dsfield: The traffic class field
+ * @dst_cache: The dst cache to use for lookup
* This function performs a route lookup on a UDP tunnel
*
* It returns a valid dst pointer and stores src address to be used in
@@ -132,20 +136,17 @@ struct dst_entry *udp_tunnel6_dst_lookup(struct sk_buff *skb,
struct net_device *dev,
struct net *net,
struct socket *sock,
+ int oif,
struct in6_addr *saddr,
- const struct ip_tunnel_info *info,
- bool use_cache)
+ const struct ip_tunnel_key *key,
+ __be16 sport, __be16 dport, u8 dsfield,
+ struct dst_cache *dst_cache)
{
struct dst_entry *dst = NULL;
-#ifdef CONFIG_DST_CACHE
- struct dst_cache *dst_cache;
-#endif
struct flowi6 fl6;
- __u8 prio;

#ifdef CONFIG_DST_CACHE
- dst_cache = (struct dst_cache *)&info->dst_cache;
- if (use_cache) {
+ if (dst_cache) {
dst = dst_cache_get_ip6(dst_cache, saddr);
if (dst)
return dst;
@@ -154,10 +155,12 @@ struct dst_entry *udp_tunnel6_dst_lookup(struct sk_buff *skb,
memset(&fl6, 0, sizeof(fl6));
fl6.flowi6_mark = skb->mark;
fl6.flowi6_proto = IPPROTO_UDP;
- fl6.daddr = info->key.u.ipv6.dst;
- fl6.saddr = info->key.u.ipv6.src;
- prio = info->key.tos;
- fl6.flowlabel = ip6_make_flowinfo(prio, info->key.label);
+ fl6.flowi6_oif = oif;
+ fl6.daddr = key->u.ipv6.dst;
+ fl6.saddr = key->u.ipv6.src;
+ fl6.fl6_sport = sport;
+ fl6.fl6_dport = dport;
+ fl6.flowlabel = ip6_make_flowinfo(dsfield, key->label);

dst = ipv6_stub->ipv6_dst_lookup_flow(net, sock->sk, &fl6,
NULL);
@@ -171,7 +174,7 @@ struct dst_entry *udp_tunnel6_dst_lookup(struct sk_buff *skb,
return ERR_PTR(-ELOOP);
}
#ifdef CONFIG_DST_CACHE
- if (use_cache)
+ if (dst_cache)
dst_cache_set_ip6(dst_cache, dst, &fl6.saddr);
#endif
*saddr = fl6.saddr;
--
2.40.1


2023-10-20 15:54:05

by David Ahern

[permalink] [raw]
Subject: Re: [PATCH net-next 3/5] ipv6: add new arguments to udp_tunnel6_dst_lookup()

On 10/20/23 5:55 AM, Beniamino Galvani wrote:
> We want to make the function more generic so that it can be used by
> other UDP tunnel implementations such as geneve and vxlan. To do that,
> add the following arguments:
>
> - source and destination UDP port;
> - ifindex of the output interface, needed by vxlan;
> - the tos, because in some cases it is not taken from struct
> ip_tunnel_info (for example, when it's inherited from the inner
> packet);
> - the dst cache, because not all tunnel types (e.g. vxlan) want to
> use the one from struct ip_tunnel_info.
>
> With these parameters, the function no longer needs the full struct
> ip_tunnel_info as argument and we can pass only the relevant part of
> it (struct ip_tunnel_key).
>
> This is similar to what already done for IPv4 in commit 72fc68c6356b
> ("ipv4: add new arguments to udp_tunnel_dst_lookup()").
>
> Suggested-by: Guillaume Nault <[email protected]>
> Signed-off-by: Beniamino Galvani <[email protected]>
> ---
> drivers/net/bareudp.c | 10 +++++++---
> include/net/udp_tunnel.h | 7 ++++---
> net/ipv6/ip6_udp_tunnel.c | 33 ++++++++++++++++++---------------
> 3 files changed, 29 insertions(+), 21 deletions(-)
>

Reviewed-by: David Ahern <[email protected]>