Commit d77a721d authored by Pablo Neira Ayuso's avatar Pablo Neira Ayuso
Browse files

netfilter: nft_socket: track register operations 



Check if the destination register already contains the data that this
socket expression performs. This allows to skip this redundant
operation.  If the destination contains a different selector, update the
register tracking information.

Signed-off-by: default avatarPablo Neira Ayuso <pablo@netfilter.org>
parent 71ef842d

net/netfilter/nft_socket.c

+28 −0
Original line number Diff line number Diff line
@@ -10,6 +10,7 @@ 
struct nft_socket {

	enum nft_socket_keys		key:8;

	u8				level;

	u8				len;

	union {

		u8			dreg;

	};
@@ -179,6 +180,7 @@ static int nft_socket_init(const struct nft_ctx *ctx, 
		return -EOPNOTSUPP;

	}



	priv->len = len;

	return nft_parse_register_store(ctx, tb[NFTA_SOCKET_DREG], &priv->dreg,

					NULL, NFT_DATA_VALUE, len);

}
@@ -198,6 +200,31 @@ static int nft_socket_dump(struct sk_buff *skb, 
	return 0;

}



static bool nft_socket_reduce(struct nft_regs_track *track,

			      const struct nft_expr *expr)

{

	const struct nft_socket *priv = nft_expr_priv(expr);

	const struct nft_socket *socket;



	if (!nft_reg_track_cmp(track, expr, priv->dreg)) {

		nft_reg_track_update(track, expr, priv->dreg, priv->len);

		return false;

	}



	socket = nft_expr_priv(track->regs[priv->dreg].selector);

	if (priv->key != socket->key ||

	    priv->dreg != socket->dreg ||

	    priv->level != socket->level) {

		nft_reg_track_update(track, expr, priv->dreg, priv->len);

		return false;

	}



	if (!track->regs[priv->dreg].bitwise)

		return true;



	return nft_expr_reduce_bitwise(track, expr);

}



static struct nft_expr_type nft_socket_type;

static const struct nft_expr_ops nft_socket_ops = {

	.type		= &nft_socket_type,
@@ -205,6 +232,7 @@ static const struct nft_expr_ops nft_socket_ops = { 
	.eval		= nft_socket_eval,

	.init		= nft_socket_init,

	.dump		= nft_socket_dump,

	.reduce		= nft_socket_reduce,

};



static struct nft_expr_type nft_socket_type __read_mostly = {