Commit ffe6488e authored by Pablo Neira Ayuso's avatar Pablo Neira Ayuso
Browse files

netfilter: nft_osf: track register operations 



Allow to recycle the previous output of the OS fingerprint expression
if flags and ttl are the same.

Signed-off-by: default avatarPablo Neira Ayuso <pablo@netfilter.org>
parent 4e2b29d8

net/netfilter/nft_osf.c

+25 −0
Original line number Original line Diff line number Diff line
@@ -120,6 +120,30 @@ static int nft_osf_validate(const struct nft_ctx *ctx, 
						    (1 << NF_INET_FORWARD));

						    (1 << NF_INET_FORWARD));

}

}





static bool nft_osf_reduce(struct nft_regs_track *track,

			   const struct nft_expr *expr)

{

	struct nft_osf *priv = nft_expr_priv(expr);

	struct nft_osf *osf;



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

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

		return false;

	}



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

	if (priv->flags != osf->flags ||

	    priv->ttl != osf->ttl) {

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

		return false;

	}



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

		return true;



	return false;

}



static struct nft_expr_type nft_osf_type;

static struct nft_expr_type nft_osf_type;

static const struct nft_expr_ops nft_osf_op = {

static const struct nft_expr_ops nft_osf_op = {

	.eval		= nft_osf_eval,

	.eval		= nft_osf_eval,
@@ -128,6 +152,7 @@ static const struct nft_expr_ops nft_osf_op = { 
	.dump		= nft_osf_dump,

	.dump		= nft_osf_dump,

	.type		= &nft_osf_type,

	.type		= &nft_osf_type,

	.validate	= nft_osf_validate,

	.validate	= nft_osf_validate,

	.reduce		= nft_osf_reduce,

};

};





static struct nft_expr_type nft_osf_type __read_mostly = {

static struct nft_expr_type nft_osf_type __read_mostly = {