[PATCH net-next 2/2] net: sched: act_tunnel_key: make UDP checksum configurable

[Jiri Benc]

Allow requesting of zero UDP checksum for encapsulated packets. The name and
meaning of the attribute is "NO_CSUM" in order to have the same meaning of
the attribute missing and being 0.

Signed-off-by: Jiri Benc <jb...@redhat.com>
---
 include/uapi/linux/tc_act/tc_tunnel_key.h |  1 +
 net/sched/act_tunnel_key.c                | 15 ++++++++++++---
 2 files changed, 13 insertions(+), 3 deletions(-)

diff --git a/include/uapi/linux/tc_act/tc_tunnel_key.h 
b/include/uapi/linux/tc_act/tc_tunnel_key.h
index 84ea55e1076b..afcd4be953e2 100644
--- a/include/uapi/linux/tc_act/tc_tunnel_key.h
+++ b/include/uapi/linux/tc_act/tc_tunnel_key.h
@@ -34,6 +34,7 @@ enum {
        TCA_TUNNEL_KEY_ENC_KEY_ID,      /* be64 */
        TCA_TUNNEL_KEY_PAD,
        TCA_TUNNEL_KEY_ENC_DST_PORT,    /* be16 */
+       TCA_TUNNEL_KEY_NO_CSUM,         /* u8 */
        __TCA_TUNNEL_KEY_MAX,
 };
 
diff --git a/net/sched/act_tunnel_key.c b/net/sched/act_tunnel_key.c
index b90effa10eb5..fd7e75679c69 100644
--- a/net/sched/act_tunnel_key.c
+++ b/net/sched/act_tunnel_key.c
@@ -67,6 +67,7 @@ static int tunnel_key_act(struct sk_buff *skb, const struct 
tc_action *a,
        [TCA_TUNNEL_KEY_ENC_IPV6_DST] = { .len = sizeof(struct in6_addr) },
        [TCA_TUNNEL_KEY_ENC_KEY_ID]   = { .type = NLA_U32 },
        [TCA_TUNNEL_KEY_ENC_DST_PORT] = {.type = NLA_U16},
+       [TCA_TUNNEL_KEY_NO_CSUM]      = { .type = NLA_U8 },
 };
 
 static int tunnel_key_init(struct net *net, struct nlattr *nla,
@@ -83,6 +84,7 @@ static int tunnel_key_init(struct net *net, struct nlattr 
*nla,
        bool exists = false;
        __be16 dst_port = 0;
        __be64 key_id;
+       __be16 flags;
        int ret = 0;
        int err;
 
@@ -113,6 +115,11 @@ static int tunnel_key_init(struct net *net, struct nlattr 
*nla,
 
                key_id = 
key32_to_tunnel_id(nla_get_be32(tb[TCA_TUNNEL_KEY_ENC_KEY_ID]));
 
+               flags = TUNNEL_KEY | TUNNEL_CSUM;
+               if (tb[TCA_TUNNEL_KEY_NO_CSUM] &&
+                   nla_get_u8(tb[TCA_TUNNEL_KEY_NO_CSUM]))
+                       flags &= ~TUNNEL_CSUM;
+
                if (tb[TCA_TUNNEL_KEY_ENC_DST_PORT])
                        dst_port = 
nla_get_be16(tb[TCA_TUNNEL_KEY_ENC_DST_PORT]);
 
@@ -125,7 +132,7 @@ static int tunnel_key_init(struct net *net, struct nlattr 
*nla,
                        daddr = 
nla_get_in_addr(tb[TCA_TUNNEL_KEY_ENC_IPV4_DST]);
 
                        metadata = __ip_tun_set_dst(saddr, daddr, 0, 0,
-                                                   dst_port, TUNNEL_KEY | 
TUNNEL_CSUM,
+                                                   dst_port, flags,
                                                    key_id, 0);
                } else if (tb[TCA_TUNNEL_KEY_ENC_IPV6_SRC] &&
                           tb[TCA_TUNNEL_KEY_ENC_IPV6_DST]) {
@@ -136,7 +143,7 @@ static int tunnel_key_init(struct net *net, struct nlattr 
*nla,
                        daddr = 
nla_get_in6_addr(tb[TCA_TUNNEL_KEY_ENC_IPV6_DST]);
 
                        metadata = __ipv6_tun_set_dst(&saddr, &daddr, 0, 0, 
dst_port,
-                                                     0, TUNNEL_KEY | 
TUNNEL_CSUM,
+                                                     0, flags,
                                                      key_id, 0);
                }
 
@@ -266,7 +273,9 @@ static int tunnel_key_dump(struct sk_buff *skb, struct 
tc_action *a,
                if (nla_put_be32(skb, TCA_TUNNEL_KEY_ENC_KEY_ID, key_id) ||
                    tunnel_key_dump_addresses(skb,
                                              
&params->tcft_enc_metadata->u.tun_info) ||
-                   nla_put_be16(skb, TCA_TUNNEL_KEY_ENC_DST_PORT, key->tp_dst))
+                   nla_put_be16(skb, TCA_TUNNEL_KEY_ENC_DST_PORT, key->tp_dst) 
||
+                   nla_put_u8(skb, TCA_TUNNEL_KEY_NO_CSUM,
+                              !(key->tun_flags & TUNNEL_CSUM)))
                        goto nla_put_failure;
        }
 
-- 
1.8.3.1