[PATCH nf-next 2/5] netfilter: Modify nf_flow_skb_encap_protocol() to return int intead of bool

[Lorenzo Bianconi]

Change nf_flow_skb_encap_protocol signature in order to return int error
code instead of a boolean value. This is a preliminary patch to introduce
IP6IP6 flowtable acceleration.

Signed-off-by: Lorenzo Bianconi <lore...@kernel.org>
---
 net/netfilter/nf_flow_table_ip.c | 28 ++++++++++++++--------------
 1 file changed, 14 insertions(+), 14 deletions(-)

diff --git a/net/netfilter/nf_flow_table_ip.c b/net/netfilter/nf_flow_table_ip.c
index 
14c01b59f76569170057d2465ee5953efb557bcc..9dbb4eed7724edbd68d386bb48bc237527ea7368
 100644
--- a/net/netfilter/nf_flow_table_ip.c
+++ b/net/netfilter/nf_flow_table_ip.c
@@ -297,23 +297,23 @@ static unsigned int nf_flow_xmit_xfrm(struct sk_buff *skb,
        return NF_STOLEN;
 }
 
-static bool nf_flow_ip4_tunnel_proto(struct nf_flowtable_ctx *ctx,
-                                    struct sk_buff *skb)
+static int nf_flow_ip4_tunnel_proto(struct nf_flowtable_ctx *ctx,
+                                   struct sk_buff *skb)
 {
        struct iphdr *iph;
        u16 size;
 
        if (!pskb_may_pull(skb, sizeof(*iph) + ctx->offset))
-               return false;
+               return -1;
 
        iph = (struct iphdr *)(skb_network_header(skb) + ctx->offset);
        size = iph->ihl << 2;
 
        if (ip_is_fragment(iph) || unlikely(ip_has_options(size)))
-               return false;
+               return -1;
 
        if (iph->ttl <= 1)
-               return false;
+               return -1;
 
        if (iph->protocol == IPPROTO_IPIP) {
                ctx->tun.proto = IPPROTO_IPIP;
@@ -321,7 +321,7 @@ static bool nf_flow_ip4_tunnel_proto(struct 
nf_flowtable_ctx *ctx,
                ctx->offset += size;
        }
 
-       return true;
+       return 0;
 }
 
 static void nf_flow_ip4_tunnel_pop(struct nf_flowtable_ctx *ctx,
@@ -334,30 +334,30 @@ static void nf_flow_ip4_tunnel_pop(struct 
nf_flowtable_ctx *ctx,
        skb_reset_network_header(skb);
 }
 
-static bool nf_flow_skb_encap_protocol(struct nf_flowtable_ctx *ctx,
-                                      struct sk_buff *skb, __be16 proto)
+static int nf_flow_skb_encap_protocol(struct nf_flowtable_ctx *ctx,
+                                     struct sk_buff *skb, __be16 proto)
 {
        __be16 inner_proto = skb->protocol;
        struct vlan_ethhdr *veth;
-       bool ret = false;
+       int ret = -1;
 
        switch (skb->protocol) {
        case htons(ETH_P_8021Q):
                if (!pskb_may_pull(skb, skb_mac_offset(skb) + sizeof(*veth)))
-                       return false;
+                       return -1;
 
                veth = (struct vlan_ethhdr *)skb_mac_header(skb);
                if (veth->h_vlan_encapsulated_proto == proto) {
                        ctx->offset += VLAN_HLEN;
                        inner_proto = proto;
-                       ret = true;
+                       ret = 0;
                }
                break;
        case htons(ETH_P_PPP_SES):
                if (nf_flow_pppoe_proto(skb, &inner_proto) &&
                    inner_proto == proto) {
                        ctx->offset += PPPOE_SES_HLEN;
-                       ret = true;
+                       ret = 0;
                }
                break;
        }
@@ -422,7 +422,7 @@ nf_flow_offload_lookup(struct nf_flowtable_ctx *ctx,
 {
        struct flow_offload_tuple tuple = {};
 
-       if (!nf_flow_skb_encap_protocol(ctx, skb, htons(ETH_P_IP)))
+       if (nf_flow_skb_encap_protocol(ctx, skb, htons(ETH_P_IP)) < 0)
                return NULL;
 
        if (nf_flow_tuple_ip(ctx, skb, &tuple) < 0)
@@ -903,7 +903,7 @@ nf_flow_offload_ipv6_lookup(struct nf_flowtable_ctx *ctx,
        struct flow_offload_tuple tuple = {};
 
        if (skb->protocol != htons(ETH_P_IPV6) &&
-           !nf_flow_skb_encap_protocol(ctx, skb, htons(ETH_P_IPV6)))
+           nf_flow_skb_encap_protocol(ctx, skb, htons(ETH_P_IPV6)) < 0)
                return NULL;
 
        if (nf_flow_tuple_ipv6(ctx, skb, &tuple) < 0)

-- 
2.52.0