Commit aed8ee7f authored by Kumar Kartikeya Dwivedi's avatar Kumar Kartikeya Dwivedi Committed by Alexei Starovoitov
Browse files

net: netfilter: Deduplicate code in bpf_{xdp,skb}_ct_lookup 



Move common checks inside the common function, and maintain the only
difference the two being how to obtain the struct net * from ctx.
No functional change intended.

Signed-off-by: default avatarKumar Kartikeya Dwivedi <memxor@gmail.com>
Link: https://lore.kernel.org/r/20220721134245.2450-7-memxor@gmail.com


Signed-off-by: default avatarAlexei Starovoitov <ast@kernel.org>
parent 63e564eb

net/netfilter/nf_conntrack_bpf.c

+18 −34
Original line number Diff line number Diff line
@@ -57,16 +57,19 @@ enum { 


static struct nf_conn *__bpf_nf_ct_lookup(struct net *net,

					  struct bpf_sock_tuple *bpf_tuple,

					  u32 tuple_len, u8 protonum,

					  s32 netns_id, u8 *dir)

					  u32 tuple_len, struct bpf_ct_opts *opts,

					  u32 opts_len)

{

	struct nf_conntrack_tuple_hash *hash;

	struct nf_conntrack_tuple tuple;

	struct nf_conn *ct;



	if (unlikely(protonum != IPPROTO_TCP && protonum != IPPROTO_UDP))

	if (!opts || !bpf_tuple || opts->reserved[0] || opts->reserved[1] ||

	    opts_len != NF_BPF_CT_OPTS_SZ)

		return ERR_PTR(-EINVAL);

	if (unlikely(opts->l4proto != IPPROTO_TCP && opts->l4proto != IPPROTO_UDP))

		return ERR_PTR(-EPROTO);

	if (unlikely(netns_id < BPF_F_CURRENT_NETNS))

	if (unlikely(opts->netns_id < BPF_F_CURRENT_NETNS))

		return ERR_PTR(-EINVAL);



	memset(&tuple, 0, sizeof(tuple));
@@ -89,23 +92,22 @@ static struct nf_conn *__bpf_nf_ct_lookup(struct net *net, 
		return ERR_PTR(-EAFNOSUPPORT);

	}



	tuple.dst.protonum = protonum;

	tuple.dst.protonum = opts->l4proto;



	if (netns_id >= 0) {

		net = get_net_ns_by_id(net, netns_id);

	if (opts->netns_id >= 0) {

		net = get_net_ns_by_id(net, opts->netns_id);

		if (unlikely(!net))

			return ERR_PTR(-ENONET);

	}



	hash = nf_conntrack_find_get(net, &nf_ct_zone_dflt, &tuple);

	if (netns_id >= 0)

	if (opts->netns_id >= 0)

		put_net(net);

	if (!hash)

		return ERR_PTR(-ENOENT);



	ct = nf_ct_tuplehash_to_ctrack(hash);

	if (dir)

		*dir = NF_CT_DIRECTION(hash);

	opts->dir = NF_CT_DIRECTION(hash);



	return ct;

}
@@ -138,19 +140,10 @@ bpf_xdp_ct_lookup(struct xdp_md *xdp_ctx, struct bpf_sock_tuple *bpf_tuple, 
	struct net *caller_net;

	struct nf_conn *nfct;



	BUILD_BUG_ON(sizeof(struct bpf_ct_opts) != NF_BPF_CT_OPTS_SZ);



	if (!opts)

		return NULL;

	if (!bpf_tuple || opts->reserved[0] || opts->reserved[1] ||

	    opts__sz != NF_BPF_CT_OPTS_SZ) {

		opts->error = -EINVAL;

		return NULL;

	}

	caller_net = dev_net(ctx->rxq->dev);

	nfct = __bpf_nf_ct_lookup(caller_net, bpf_tuple, tuple__sz, opts->l4proto,

				  opts->netns_id, &opts->dir);

	nfct = __bpf_nf_ct_lookup(caller_net, bpf_tuple, tuple__sz, opts, opts__sz);

	if (IS_ERR(nfct)) {

		if (opts)

			opts->error = PTR_ERR(nfct);

		return NULL;

	}
@@ -181,19 +174,10 @@ bpf_skb_ct_lookup(struct __sk_buff *skb_ctx, struct bpf_sock_tuple *bpf_tuple, 
	struct net *caller_net;

	struct nf_conn *nfct;



	BUILD_BUG_ON(sizeof(struct bpf_ct_opts) != NF_BPF_CT_OPTS_SZ);



	if (!opts)

		return NULL;

	if (!bpf_tuple || opts->reserved[0] || opts->reserved[1] ||

	    opts__sz != NF_BPF_CT_OPTS_SZ) {

		opts->error = -EINVAL;

		return NULL;

	}

	caller_net = skb->dev ? dev_net(skb->dev) : sock_net(skb->sk);

	nfct = __bpf_nf_ct_lookup(caller_net, bpf_tuple, tuple__sz, opts->l4proto,

				  opts->netns_id, &opts->dir);

	nfct = __bpf_nf_ct_lookup(caller_net, bpf_tuple, tuple__sz, opts, opts__sz);

	if (IS_ERR(nfct)) {

		if (opts)

			opts->error = PTR_ERR(nfct);

		return NULL;

	}