net/netfilter/nft_dynset.c

Source file repositories/reference/linux-study-clean/net/netfilter/nft_dynset.c

File Facts

System
Linux kernel
Corpus path
net/netfilter/nft_dynset.c
Extension
.c
Size
11233 bytes
Lines
442
Domain
Networking Core
Bucket
Sockets, Protocols, Packet Path, And Network Policy
Inferred role
Networking Core: implementation source
Status
source implementation candidate

Why This File Exists

Networking stack implementation surface: socket APIs, protocol dispatch, packet flow, routing, filtering, and network namespaces.

Dependency Surface

Detected Declarations

Annotated Snippet

struct nft_dynset {
	struct nft_set			*set;
	struct nft_set_ext_tmpl		tmpl;
	enum nft_dynset_ops		op:8;
	u8				sreg_key;
	u8				sreg_data;
	bool				invert;
	bool				expr;
	u8				num_exprs;
	u64				timeout;
	struct nft_expr			*expr_array[NFT_SET_EXPR_MAX];
	struct nft_set_binding		binding;
};

static int nft_dynset_expr_setup(const struct nft_dynset *priv,
				 const struct nft_set_ext *ext)
{
	struct nft_set_elem_expr *elem_expr = nft_set_ext_expr(ext);
	struct nft_ctx ctx = {
		.net	= read_pnet(&priv->set->net),
		.family	= priv->set->table->family,
	};
	struct nft_expr *expr;
	int i;

	for (i = 0; i < priv->num_exprs; i++) {
		expr = nft_setelem_expr_at(elem_expr, elem_expr->size);
		if (nft_expr_clone(expr, priv->expr_array[i], GFP_ATOMIC) < 0)
			goto err_out;

		elem_expr->size += priv->expr_array[i]->ops->size;
	}

	return 0;
err_out:
	nft_set_elem_expr_destroy(&ctx, elem_expr);

	return -1;
}

struct nft_elem_priv *nft_dynset_new(struct nft_set *set,
				     const struct nft_expr *expr,
				     struct nft_regs *regs)
{
	const struct nft_dynset *priv = nft_expr_priv(expr);
	struct nft_set_ext *ext;
	void *elem_priv;
	u64 timeout;

	if (!atomic_add_unless(&set->nelems, 1, set->size))
		return NULL;

	timeout = priv->timeout ? : READ_ONCE(set->timeout);
	elem_priv = nft_set_elem_init(set, &priv->tmpl,
				      &regs->data[priv->sreg_key], NULL,
				      &regs->data[priv->sreg_data],
				      timeout, 0, GFP_ATOMIC);
	if (IS_ERR(elem_priv))
		goto err1;

	ext = nft_set_elem_ext(set, elem_priv);
	if (priv->num_exprs && nft_dynset_expr_setup(priv, ext) < 0)
		goto err2;

	return elem_priv;

err2:
	nft_set_elem_destroy(set, elem_priv, false);
err1:
	if (set->size)
		atomic_dec(&set->nelems);
	return NULL;
}

void nft_dynset_eval(const struct nft_expr *expr,
		     struct nft_regs *regs, const struct nft_pktinfo *pkt)
{
	const struct nft_dynset *priv = nft_expr_priv(expr);
	struct nft_set *set = priv->set;
	const struct nft_set_ext *ext;
	u64 timeout;

	if (priv->op == NFT_DYNSET_OP_DELETE) {
		set->ops->delete(set, &regs->data[priv->sreg_key]);
		return;
	}

	ext = set->ops->update(set, &regs->data[priv->sreg_key], expr, regs);
	if (ext) {
		if (priv->op == NFT_DYNSET_OP_UPDATE &&

Annotation

Implementation Notes