initial version of libnftables

It adds support for table, chain and rule handling.

This also includes expression handling for each rule.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

1 files changed, 145 insertions, 0 deletions

diff --git a/src/expr/counter.c b/src/expr/counter.c
new file mode 100644
index 0000000..26b7d6f
--- /dev/null
+++ b/src/expr/counter.c
@@ -0,0 +1,145 @@
+/*
+ * (C) 2012 by Pablo Neira Ayuso <pablo@netfilter.org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published
+ * by the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This code has been sponsored by Sophos Astaro <http://www.sophos.com>
+ */
+
+#include <stdio.h>
+#include <stdint.h>
+#include <arpa/inet.h>
+
+#include <linux/netfilter/nf_tables.h>
+
+#include "internal.h"
+#include <libmnl/libmnl.h>
+#include <libnftables/expr.h>
+#include "expr_ops.h"
+
+struct nft_expr_counter {
+	uint64_t	pkts;
+	uint64_t	bytes;
+};
+
+static int
+nft_rule_expr_counter_set(struct nft_rule_expr *e, uint16_t type,
+			  const void *data, size_t data_len)
+{
+	struct nft_expr_counter *ctr = (struct nft_expr_counter *)e->data;
+
+	switch(type) {
+	case NFT_EXPR_CTR_BYTES:
+		ctr->bytes = *((uint64_t *)data);
+		break;
+	case NFT_EXPR_CTR_PACKETS:
+		ctr->pkts = *((uint64_t *)data);
+		break;
+	default:
+		return -1;
+	}
+	return 0;
+}
+
+static const void *
+nft_rule_expr_counter_get(struct nft_rule_expr *e, uint16_t type, size_t *data_len)
+{
+	struct nft_expr_counter *ctr = (struct nft_expr_counter *)e->data;
+
+	switch(type) {
+	case NFT_EXPR_CTR_BYTES:
+		if (e->flags & (1 << NFT_EXPR_CTR_BYTES)) {
+			*data_len = sizeof(ctr->bytes);
+			return &ctr->bytes;
+		} else
+			return NULL;
+		break;
+	case NFT_EXPR_CTR_PACKETS:
+		if (e->flags & (1 << NFT_EXPR_CTR_PACKETS)) {
+			*data_len = sizeof(ctr->pkts);
+			return &ctr->pkts;
+		} else
+			return NULL;
+		break;
+	default:
+		break;
+	}
+	return NULL;
+}
+
+static int nft_rule_expr_counter_cb(const struct nlattr *attr, void *data)
+{
+	const struct nlattr **tb = data;
+	int type = mnl_attr_get_type(attr);
+
+	if (mnl_attr_type_valid(attr, NFTA_COUNTER_MAX) < 0)
+		return MNL_CB_OK;
+
+	switch(type) {
+	case NFTA_COUNTER_BYTES:
+	case NFTA_COUNTER_PACKETS:
+		if (mnl_attr_validate(attr, MNL_TYPE_U64) < 0) {
+			perror("mnl_attr_validate");
+			return MNL_CB_ERROR;
+		}
+		break;
+	}
+
+	tb[type] = attr;
+	return MNL_CB_OK;
+}
+
+static void
+nft_rule_expr_counter_build(struct nlmsghdr *nlh, struct nft_rule_expr *e)
+{
+	struct nft_expr_counter *ctr = (struct nft_expr_counter *)e->data;
+
+	if (e->flags & (1 << NFT_EXPR_CTR_BYTES))
+		mnl_attr_put_u64(nlh, NFTA_COUNTER_BYTES, htobe64(ctr->bytes));
+	if (e->flags & (1 << NFT_EXPR_CTR_PACKETS))
+		mnl_attr_put_u64(nlh, NFTA_COUNTER_PACKETS, htobe64(ctr->pkts));
+}
+
+static int
+nft_rule_expr_counter_parse(struct nft_rule_expr *e, struct nlattr *attr)
+{
+	struct nft_expr_counter *ctr = (struct nft_expr_counter *)e->data;
+	struct nlattr *tb[NFTA_COUNTER_MAX+1] = {};
+
+	if (mnl_attr_parse_nested(attr, nft_rule_expr_counter_cb, tb) < 0)
+		return -1;
+
+	if (tb[NFTA_COUNTER_BYTES]) {
+		ctr->bytes = be64toh(mnl_attr_get_u64(tb[NFTA_COUNTER_BYTES]));
+		e->flags |= (1 << NFT_EXPR_CTR_BYTES);
+	}
+	if (tb[NFTA_COUNTER_PACKETS]) {
+		ctr->pkts = be64toh(mnl_attr_get_u64(tb[NFTA_COUNTER_PACKETS]));
+		e->flags |= (1 << NFT_EXPR_CTR_PACKETS);
+	}
+
+	return 0;
+}
+
+static int
+nft_rule_expr_counter_snprintf(char *buf, size_t len, struct nft_rule_expr *e)
+{
+	struct nft_expr_counter *ctr = (struct nft_expr_counter *)e->data;
+
+	return snprintf(buf, len, "pkts=%lu bytes=%lu ",
+			ctr->pkts, ctr->bytes);
+}
+
+struct expr_ops expr_ops_counter = {
+	.name		= "counter",
+	.alloc_len	= sizeof(struct nft_expr_counter),
+	.max_attr	= NFTA_COUNTER_MAX,
+	.set		= nft_rule_expr_counter_set,
+	.get		= nft_rule_expr_counter_get,
+	.parse		= nft_rule_expr_counter_parse,
+	.build		= nft_rule_expr_counter_build,
+	.snprintf	= nft_rule_expr_counter_snprintf,
+};