On Thu, 3 Feb 2022, Toshiaki Makita wrote:
> Support GREv0 without NAT.
>
> Signed-off-by: Toshiaki Makita <toshiaki.makita1@xxxxxxxxx>
> ---
> net/sched/act_ct.c | 101 +++++++++++++++++++++++++++++++++++++++++------------
> 1 file changed, 79 insertions(+), 22 deletions(-)
>
> diff --git a/net/sched/act_ct.c b/net/sched/act_ct.c
> index f99247f..a5f47d5 100644
> --- a/net/sched/act_ct.c
> +++ b/net/sched/act_ct.c
> @@ -421,6 +421,19 @@ static void tcf_ct_flow_table_process_conn(struct tcf_ct_flow_table *ct_ft,
> break;
> case IPPROTO_UDP:
> break;
> +#ifdef CONFIG_NF_CT_PROTO_GRE
> + case IPPROTO_GRE: {
> + struct nf_conntrack_tuple *tuple;
> +
> + if (ct->status & IPS_NAT_MASK)
> + return;
> + tuple = &ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple;
> + /* No support for GRE v1 */
> + if (tuple->src.u.gre.key || tuple->dst.u.gre.key)
> + return;
> + break;
> + }
> +#endif
> default:
> return;
> }
> @@ -440,6 +453,8 @@ static void tcf_ct_flow_table_process_conn(struct tcf_ct_flow_table *ct_ft,
> struct flow_ports *ports;
> unsigned int thoff;
> struct iphdr *iph;
> + size_t hdrsize;
> + u8 ipproto;
>
> if (!pskb_network_may_pull(skb, sizeof(*iph)))
> return false;
> @@ -451,29 +466,49 @@ static void tcf_ct_flow_table_process_conn(struct tcf_ct_flow_table *ct_ft,
> unlikely(thoff != sizeof(struct iphdr)))
> return false;
>
> - if (iph->protocol != IPPROTO_TCP &&
> - iph->protocol != IPPROTO_UDP)
> + ipproto = iph->protocol;
> + switch (ipproto) {
> + case IPPROTO_TCP:
> + hdrsize = sizeof(struct tcphdr);
> + break;
> + case IPPROTO_UDP:
> + hdrsize = sizeof(*ports);
> + break;
> +#ifdef CONFIG_NF_CT_PROTO_GRE
> + case IPPROTO_GRE:
> + hdrsize = sizeof(struct gre_base_hdr);
> + break;
> +#endif
> + default:
> return false;
> + }
>
> if (iph->ttl <= 1)
> return false;
>
> - if (!pskb_network_may_pull(skb, iph->protocol == IPPROTO_TCP ?
> - thoff + sizeof(struct tcphdr) :
> - thoff + sizeof(*ports)))
> + if (!pskb_network_may_pull(skb, thoff + hdrsize))
> return false;
>
> iph = ip_hdr(skb);
> - if (iph->protocol == IPPROTO_TCP)
> + if (ipproto == IPPROTO_TCP) {
> *tcph = (void *)(skb_network_header(skb) + thoff);
> + } else if (ipproto == IPPROTO_GRE) {
> + struct gre_base_hdr *greh;
> +
> + greh = (struct gre_base_hdr *)(skb_network_header(skb) + thoff);
> + if ((greh->flags & GRE_VERSION) != GRE_VERSION_0)
> + return false;
> + }
>
> - ports = (struct flow_ports *)(skb_network_header(skb) + thoff);
> tuple->src_v4.s_addr = iph->saddr;
> tuple->dst_v4.s_addr = iph->daddr;
> - tuple->src_port = ports->source;
> - tuple->dst_port = ports->dest;
> + if (ipproto == IPPROTO_TCP || ipproto == IPPROTO_UDP) {
> + ports = (struct flow_ports *)(skb_network_header(skb) + thoff);
> + tuple->src_port = ports->source;
> + tuple->dst_port = ports->dest;
> + }
> tuple->l3proto = AF_INET;
> - tuple->l4proto = iph->protocol;
> + tuple->l4proto = ipproto;
>
> return true;
> }
> @@ -486,36 +521,58 @@ static void tcf_ct_flow_table_process_conn(struct tcf_ct_flow_table *ct_ft,
> struct flow_ports *ports;
> struct ipv6hdr *ip6h;
> unsigned int thoff;
> + size_t hdrsize;
> + u8 nexthdr;
>
> if (!pskb_network_may_pull(skb, sizeof(*ip6h)))
> return false;
>
> ip6h = ipv6_hdr(skb);
> + thoff = sizeof(*ip6h);
>
> - if (ip6h->nexthdr != IPPROTO_TCP &&
> - ip6h->nexthdr != IPPROTO_UDP)
> - return false;
> + nexthdr = ip6h->nexthdr;
> + switch (nexthdr) {
> + case IPPROTO_TCP:
> + hdrsize = sizeof(struct tcphdr);
> + break;
> + case IPPROTO_UDP:
> + hdrsize = sizeof(*ports);
> + break;
> +#ifdef CONFIG_NF_CT_PROTO_GRE
> + case IPPROTO_GRE:
> + hdrsize = sizeof(struct gre_base_hdr);
> + break;
> +#endif
> + default:
> + return -1;
> + }
>
> if (ip6h->hop_limit <= 1)
> return false;
>
> - thoff = sizeof(*ip6h);
> - if (!pskb_network_may_pull(skb, ip6h->nexthdr == IPPROTO_TCP ?
> - thoff + sizeof(struct tcphdr) :
> - thoff + sizeof(*ports)))
> + if (!pskb_network_may_pull(skb, thoff + hdrsize))
> return false;
>
> ip6h = ipv6_hdr(skb);
> - if (ip6h->nexthdr == IPPROTO_TCP)
> + if (nexthdr == IPPROTO_TCP) {
> *tcph = (void *)(skb_network_header(skb) + thoff);
> + } else if (nexthdr == IPPROTO_GRE) {
> + struct gre_base_hdr *greh;
> +
> + greh = (struct gre_base_hdr *)(skb_network_header(skb) + thoff);
> + if ((greh->flags & GRE_VERSION) != GRE_VERSION_0)
> + return false;
> + }
>
> - ports = (struct flow_ports *)(skb_network_header(skb) + thoff);
> tuple->src_v6 = ip6h->saddr;
> tuple->dst_v6 = ip6h->daddr;
> - tuple->src_port = ports->source;
> - tuple->dst_port = ports->dest;
> + if (nexthdr == IPPROTO_TCP || nexthdr == IPPROTO_UDP) {
> + ports = (struct flow_ports *)(skb_network_header(skb) + thoff);
> + tuple->src_port = ports->source;
> + tuple->dst_port = ports->dest;
> + }
> tuple->l3proto = AF_INET6;
> - tuple->l4proto = ip6h->nexthdr;
> + tuple->l4proto = nexthdr;
>
> return true;
> }
> --
> 1.8.3.1
>
>
The GRE ifdefs I assume are for the same reason you mentioned in other
patch, If so, looks good to me.
Acked-by: Paul Blakey <paulb@xxxxxxxxxx
