1 files changed, 139 insertions, 0 deletions
diff --git a/src/expr/connlimit.c b/src/expr/connlimit.c
new file mode 100644
index 0000000..549417b
--- /dev/null
+++ b/src/expr/connlimit.c
@@ -0,0 +1,139 @@
+/*
+ * (C) 2018 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.
+ */
+
+#include <stdio.h>
+#include <stdint.h>
+#include <arpa/inet.h>
+#include <errno.h>
+#include <inttypes.h>
+
+#include <linux/netfilter/nf_tables.h>
+
+#include "internal.h"
+#include <libmnl/libmnl.h>
+#include <libnftnl/expr.h>
+#include <libnftnl/rule.h>
+
+struct nftnl_expr_connlimit {
+	uint32_t	count;
+	uint32_t	flags;
+};
+
+static int
+nftnl_expr_connlimit_set(struct nftnl_expr *e, uint16_t type,
+			  const void *data, uint32_t data_len)
+{
+	struct nftnl_expr_connlimit *connlimit = nftnl_expr_data(e);
+
+	switch(type) {
+	case NFTNL_EXPR_CONNLIMIT_COUNT:
+		memcpy(&connlimit->count, data, sizeof(connlimit->count));
+		break;
+	case NFTNL_EXPR_CONNLIMIT_FLAGS:
+		memcpy(&connlimit->flags, data, sizeof(connlimit->flags));
+		break;
+	default:
+		return -1;
+	}
+	return 0;
+}
+
+static const void *
+nftnl_expr_connlimit_get(const struct nftnl_expr *e, uint16_t type,
+			  uint32_t *data_len)
+{
+	struct nftnl_expr_connlimit *connlimit = nftnl_expr_data(e);
+
+	switch(type) {
+	case NFTNL_EXPR_CONNLIMIT_COUNT:
+		*data_len = sizeof(connlimit->count);
+		return &connlimit->count;
+	case NFTNL_EXPR_CONNLIMIT_FLAGS:
+		*data_len = sizeof(connlimit->flags);
+		return &connlimit->flags;
+	}
+	return NULL;
+}
+
+static int nftnl_expr_connlimit_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_CONNLIMIT_MAX) < 0)
+		return MNL_CB_OK;
+
+	switch(type) {
+	case NFTA_CONNLIMIT_COUNT:
+	case NFTA_CONNLIMIT_FLAGS:
+		if (mnl_attr_validate(attr, MNL_TYPE_U32) < 0)
+			abi_breakage();
+		break;
+	}
+
+	tb[type] = attr;
+	return MNL_CB_OK;
+}
+
+static void
+nftnl_expr_connlimit_build(struct nlmsghdr *nlh, const struct nftnl_expr *e)
+{
+	struct nftnl_expr_connlimit *connlimit = nftnl_expr_data(e);
+
+	if (e->flags & (1 << NFTNL_EXPR_CONNLIMIT_COUNT))
+		mnl_attr_put_u32(nlh, NFTA_CONNLIMIT_COUNT,
+				 htonl(connlimit->count));
+	if (e->flags & (1 << NFTNL_EXPR_CONNLIMIT_FLAGS))
+		mnl_attr_put_u32(nlh, NFTA_CONNLIMIT_FLAGS,
+				 htonl(connlimit->flags));
+}
+
+static int
+nftnl_expr_connlimit_parse(struct nftnl_expr *e, struct nlattr *attr)
+{
+	struct nftnl_expr_connlimit *connlimit = nftnl_expr_data(e);
+	struct nlattr *tb[NFTA_CONNLIMIT_MAX+1] = {};
+
+	if (mnl_attr_parse_nested(attr, nftnl_expr_connlimit_cb, tb) < 0)
+		return -1;
+
+	if (tb[NFTA_CONNLIMIT_COUNT]) {
+		connlimit->count =
+			ntohl(mnl_attr_get_u32(tb[NFTA_CONNLIMIT_COUNT]));
+		e->flags |= (1 << NFTNL_EXPR_CONNLIMIT_COUNT);
+	}
+	if (tb[NFTA_CONNLIMIT_FLAGS]) {
+		connlimit->flags =
+			ntohl(mnl_attr_get_u32(tb[NFTA_CONNLIMIT_FLAGS]));
+		e->flags |= (1 << NFTNL_EXPR_CONNLIMIT_FLAGS);
+	}
+
+	return 0;
+}
+
+static int nftnl_expr_connlimit_snprintf(char *buf, size_t len,
+				       uint32_t flags,
+				       const struct nftnl_expr *e)
+{
+	struct nftnl_expr_connlimit *connlimit = nftnl_expr_data(e);
+
+	return snprintf(buf, len, "count %u flags %x ",
+			connlimit->count, connlimit->flags);
+}
+
+struct expr_ops expr_ops_connlimit = {
+	.name		= "connlimit",
+	.alloc_len	= sizeof(struct nftnl_expr_connlimit),
+	.max_attr	= NFTA_CONNLIMIT_MAX,
+	.set		= nftnl_expr_connlimit_set,
+	.get		= nftnl_expr_connlimit_get,
+	.parse		= nftnl_expr_connlimit_parse,
+	.build		= nftnl_expr_connlimit_build,
+	.output		= nftnl_expr_connlimit_snprintf,
+};