Commit 611580d2 authored by Pablo Neira Ayuso's avatar Pablo Neira Ayuso
Browse files

netfilter: nft_tunnel: track register operations 



Check if the destination register already contains the data that this
tunnel expression performs. This allows to skip this redundant operation.
If the destination contains a different selector, update the register
tracking information. This patch does not perform bitwise tracking.

Signed-off-by: default avatarPablo Neira Ayuso <pablo@netfilter.org>
parent 48f19103

net/netfilter/nft_tunnel.c

+28 −0
Original line number Diff line number Diff line
@@ -17,6 +17,7 @@ struct nft_tunnel { 
	enum nft_tunnel_keys	key:8;

	u8			dreg;

	enum nft_tunnel_mode	mode:8;

	u8			len;

};



static void nft_tunnel_get_eval(const struct nft_expr *expr,
@@ -101,6 +102,7 @@ static int nft_tunnel_get_init(const struct nft_ctx *ctx, 
		priv->mode = NFT_TUNNEL_MODE_NONE;

	}



	priv->len = len;

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

					NULL, NFT_DATA_VALUE, len);

}
@@ -122,6 +124,31 @@ static int nft_tunnel_get_dump(struct sk_buff *skb, 
	return -1;

}



static bool nft_tunnel_get_reduce(struct nft_regs_track *track,

				  const struct nft_expr *expr)

{

	const struct nft_tunnel *priv = nft_expr_priv(expr);

	const struct nft_tunnel *tunnel;



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

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

		return false;

	}



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

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

	    priv->dreg != tunnel->dreg ||

	    priv->mode != tunnel->mode) {

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

		return false;

	}



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

		return true;



	return false;

}



static struct nft_expr_type nft_tunnel_type;

static const struct nft_expr_ops nft_tunnel_get_ops = {

	.type		= &nft_tunnel_type,
@@ -129,6 +156,7 @@ static const struct nft_expr_ops nft_tunnel_get_ops = { 
	.eval		= nft_tunnel_get_eval,

	.init		= nft_tunnel_get_init,

	.dump		= nft_tunnel_get_dump,

	.reduce		= nft_tunnel_get_reduce,

};



static struct nft_expr_type nft_tunnel_type __read_mostly = {