On Thu, Feb 03, 2022 at 08:59:39PM +0900, Toshiaki Makita wrote:
> Support GREv0 without NAT.
>
> Signed-off-by: Toshiaki Makita <toshiaki.makita1@xxxxxxxxx>
> ---
> net/netfilter/nf_flow_table_core.c | 10 +++++--
> net/netfilter/nf_flow_table_ip.c | 54 ++++++++++++++++++++++++++++-------
> net/netfilter/nf_flow_table_offload.c | 19 +++++++-----
> net/netfilter/nft_flow_offload.c | 13 +++++++++
> 4 files changed, 77 insertions(+), 19 deletions(-)
>
> diff --git a/net/netfilter/nf_flow_table_core.c b/net/netfilter/nf_flow_table_core.c
> index b90eca7..e66a375 100644
> --- a/net/netfilter/nf_flow_table_core.c
> +++ b/net/netfilter/nf_flow_table_core.c
> @@ -39,8 +39,14 @@
>
> ft->l3proto = ctt->src.l3num;
> ft->l4proto = ctt->dst.protonum;
> - ft->src_port = ctt->src.u.tcp.port;
> - ft->dst_port = ctt->dst.u.tcp.port;
> +
> + switch (ctt->dst.protonum) {
> + case IPPROTO_TCP:
> + case IPPROTO_UDP:
> + ft->src_port = ctt->src.u.tcp.port;
> + ft->dst_port = ctt->dst.u.tcp.port;
> + break;
> + }
> }
>
> struct flow_offload *flow_offload_alloc(struct nf_conn *ct)
> diff --git a/net/netfilter/nf_flow_table_ip.c b/net/netfilter/nf_flow_table_ip.c
> index 889cf88..48e2f58 100644
> --- a/net/netfilter/nf_flow_table_ip.c
> +++ b/net/netfilter/nf_flow_table_ip.c
> @@ -172,6 +172,7 @@ static int nf_flow_tuple_ip(struct sk_buff *skb, const struct net_device *dev,
> struct flow_ports *ports;
> unsigned int thoff;
> struct iphdr *iph;
> + u8 ipproto;
>
> if (!pskb_may_pull(skb, sizeof(*iph) + offset))
> return -1;
> @@ -185,13 +186,19 @@ static int nf_flow_tuple_ip(struct sk_buff *skb, const struct net_device *dev,
>
> thoff += offset;
>
> - switch (iph->protocol) {
> + ipproto = iph->protocol;
> + switch (ipproto) {
> case IPPROTO_TCP:
> *hdrsize = sizeof(struct tcphdr);
> break;
> case IPPROTO_UDP:
> *hdrsize = sizeof(struct udphdr);
> break;
> +#ifdef CONFIG_NF_CT_PROTO_GRE
> + case IPPROTO_GRE:
> + *hdrsize = sizeof(struct gre_base_hdr);
> + break;
> +#endif
> default:
> return -1;
> }
> @@ -202,15 +209,25 @@ static int nf_flow_tuple_ip(struct sk_buff *skb, const struct net_device *dev,
> if (!pskb_may_pull(skb, thoff + *hdrsize))
> return -1;
>
> + if (ipproto == IPPROTO_GRE) {
No ifdef here? Maybe remove these ifdef everywhere?
> + struct gre_base_hdr *greh;
> +
> + greh = (struct gre_base_hdr *)(skb_network_header(skb) + thoff);
> + if ((greh->flags & GRE_VERSION) != GRE_VERSION_0)
> + return -1;
> + }
> +
> iph = (struct iphdr *)(skb_network_header(skb) + offset);
> - 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;
> + }
maybe:
switch (ipproto) {
case IPPROTO_TCP:
case IPPROTO_UDP:
...
break;
case IPPROTO_GRE:
break;
}
?
> tuple->l3proto = AF_INET;
> - tuple->l4proto = iph->protocol;
> + tuple->l4proto = ipproto;
> tuple->iifidx = dev->ifindex;
> nf_flow_tuple_encap(skb, tuple);
>
> @@ -521,6 +538,7 @@ static int nf_flow_tuple_ipv6(struct sk_buff *skb, const struct net_device *dev,
> struct flow_ports *ports;
> struct ipv6hdr *ip6h;
> unsigned int thoff;
> + u8 nexthdr;
>
> thoff = sizeof(*ip6h) + offset;
> if (!pskb_may_pull(skb, thoff))
> @@ -528,13 +546,19 @@ static int nf_flow_tuple_ipv6(struct sk_buff *skb, const struct net_device *dev,
>
> ip6h = (struct ipv6hdr *)(skb_network_header(skb) + offset);
>
> - switch (ip6h->nexthdr) {
> + nexthdr = ip6h->nexthdr;
> + switch (nexthdr) {
> case IPPROTO_TCP:
> *hdrsize = sizeof(struct tcphdr);
> break;
> case IPPROTO_UDP:
> *hdrsize = sizeof(struct udphdr);
> break;
> +#ifdef CONFIG_NF_CT_PROTO_GRE
> + case IPPROTO_GRE:
> + *hdrsize = sizeof(struct gre_base_hdr);
> + break;
> +#endif
> default:
> return -1;
> }
> @@ -545,15 +569,25 @@ static int nf_flow_tuple_ipv6(struct sk_buff *skb, const struct net_device *dev,
> if (!pskb_may_pull(skb, thoff + *hdrsize))
> return -1;
>
> + 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 -1;
> + }
> +
> ip6h = (struct ipv6hdr *)(skb_network_header(skb) + offset);
> - 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;
> tuple->iifidx = dev->ifindex;
> nf_flow_tuple_encap(skb, tuple);
>
> diff --git a/net/netfilter/nf_flow_table_offload.c b/net/netfilter/nf_flow_table_offload.c
> index b561e0a..9b81080 100644
> --- a/net/netfilter/nf_flow_table_offload.c
> +++ b/net/netfilter/nf_flow_table_offload.c
> @@ -170,6 +170,7 @@ static int nf_flow_rule_match(struct nf_flow_match *match,
> match->dissector.used_keys |= BIT(FLOW_DISSECTOR_KEY_TCP);
> break;
> case IPPROTO_UDP:
> + case IPPROTO_GRE:
> break;
> default:
> return -EOPNOTSUPP;
> @@ -178,15 +179,19 @@ static int nf_flow_rule_match(struct nf_flow_match *match,
> key->basic.ip_proto = tuple->l4proto;
> mask->basic.ip_proto = 0xff;
>
> - key->tp.src = tuple->src_port;
> - mask->tp.src = 0xffff;
> - key->tp.dst = tuple->dst_port;
> - mask->tp.dst = 0xffff;
> -
> match->dissector.used_keys |= BIT(FLOW_DISSECTOR_KEY_META) |
> BIT(FLOW_DISSECTOR_KEY_CONTROL) |
> - BIT(FLOW_DISSECTOR_KEY_BASIC) |
> - BIT(FLOW_DISSECTOR_KEY_PORTS);
> + BIT(FLOW_DISSECTOR_KEY_BASIC);
> +
> + if (tuple->l4proto == IPPROTO_TCP || tuple->l4proto == IPPROTO_UDP) {
> + key->tp.src = tuple->src_port;
> + mask->tp.src = 0xffff;
> + key->tp.dst = tuple->dst_port;
> + mask->tp.dst = 0xffff;
> +
> + match->dissector.used_keys |= BIT(FLOW_DISSECTOR_KEY_PORTS);
> + }
> +
> return 0;
> }
>
> diff --git a/net/netfilter/nft_flow_offload.c b/net/netfilter/nft_flow_offload.c
> index 0af34ad..731b5d8 100644
> --- a/net/netfilter/nft_flow_offload.c
> +++ b/net/netfilter/nft_flow_offload.c
> @@ -298,6 +298,19 @@ static void nft_flow_offload_eval(const struct nft_expr *expr,
> 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)
> + goto out;
Why this NAT check?
> + tuple = &ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple;
> + /* No support for GRE v1 */
> + if (tuple->src.u.gre.key || tuple->dst.u.gre.key)
> + goto out;
> + break;
> + }
> +#endif
> default:
> goto out;
> }
> --
> 1.8.3.1
>
