Adding upstream version 1.2.6.upstream/1.2.6upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1172 insertions, 0 deletions

diff --git a/src/chain.c b/src/chain.c
new file mode 100644
index 0000000..dcfcd04
--- /dev/null
+++ b/src/chain.c
@@ -0,0 +1,1172 @@
+/*
+ * (C) 2012-2013 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 "internal.h"
+
+#include <time.h>
+#include <endian.h>
+#include <stdint.h>
+#include <stdlib.h>
+#include <limits.h>
+#include <string.h>
+#include <netinet/in.h>
+#include <errno.h>
+#include <inttypes.h>
+
+#include <libmnl/libmnl.h>
+#include <linux/netfilter/nfnetlink.h>
+#include <linux/netfilter/nf_tables.h>
+#include <linux/netfilter.h>
+#include <linux/netfilter_arp.h>
+
+#include <libnftnl/chain.h>
+#include <libnftnl/rule.h>
+
+struct nftnl_chain {
+	struct list_head head;
+	struct hlist_node hnode;
+
+	const char	*name;
+	const char	*type;
+	const char	*table;
+	const char	*dev;
+	const char	**dev_array;
+	int		dev_array_len;
+	uint32_t	family;
+	uint32_t	policy;
+	uint32_t	hooknum;
+	int32_t		prio;
+	uint32_t	chain_flags;
+	uint32_t	use;
+	uint64_t	packets;
+	uint64_t	bytes;
+	uint64_t	handle;
+	uint32_t	flags;
+	uint32_t	chain_id;
+
+	struct {
+		void		*data;
+		uint32_t	len;
+	} user;
+
+	struct list_head rule_list;
+};
+
+static const char *nftnl_hooknum2str(int family, int hooknum)
+{
+	switch (family) {
+	case NFPROTO_IPV4:
+	case NFPROTO_IPV6:
+	case NFPROTO_INET:
+	case NFPROTO_BRIDGE:
+		switch (hooknum) {
+		case NF_INET_PRE_ROUTING:
+			return "prerouting";
+		case NF_INET_LOCAL_IN:
+			return "input";
+		case NF_INET_FORWARD:
+			return "forward";
+		case NF_INET_LOCAL_OUT:
+			return "output";
+		case NF_INET_POST_ROUTING:
+			return "postrouting";
+		}
+		break;
+	case NFPROTO_ARP:
+		switch (hooknum) {
+		case NF_ARP_IN:
+			return "input";
+		case NF_ARP_OUT:
+			return "output";
+		case NF_ARP_FORWARD:
+			return "forward";
+		}
+		break;
+	case NFPROTO_NETDEV:
+		switch (hooknum) {
+		case NF_NETDEV_INGRESS:
+			return "ingress";
+		}
+		break;
+	}
+	return "unknown";
+}
+
+EXPORT_SYMBOL(nftnl_chain_alloc);
+struct nftnl_chain *nftnl_chain_alloc(void)
+{
+	struct nftnl_chain *c;
+
+	c = calloc(1, sizeof(struct nftnl_chain));
+	if (c == NULL)
+		return NULL;
+
+	INIT_LIST_HEAD(&c->rule_list);
+
+	return c;
+}
+
+EXPORT_SYMBOL(nftnl_chain_free);
+void nftnl_chain_free(const struct nftnl_chain *c)
+{
+	struct nftnl_rule *r, *tmp;
+	int i;
+
+	list_for_each_entry_safe(r, tmp, &c->rule_list, head)
+		nftnl_rule_free(r);
+
+	if (c->flags & (1 << NFTNL_CHAIN_NAME))
+		xfree(c->name);
+	if (c->flags & (1 << NFTNL_CHAIN_TABLE))
+		xfree(c->table);
+	if (c->flags & (1 << NFTNL_CHAIN_TYPE))
+		xfree(c->type);
+	if (c->flags & (1 << NFTNL_CHAIN_DEV))
+		xfree(c->dev);
+	if (c->flags & (1 << NFTNL_CHAIN_USERDATA))
+		xfree(c->user.data);
+	if (c->flags & (1 << NFTNL_CHAIN_DEVICES)) {
+		for (i = 0; i < c->dev_array_len; i++)
+			xfree(c->dev_array[i]);
+
+		xfree(c->dev_array);
+	}
+	xfree(c);
+}
+
+EXPORT_SYMBOL(nftnl_chain_is_set);
+bool nftnl_chain_is_set(const struct nftnl_chain *c, uint16_t attr)
+{
+	return c->flags & (1 << attr);
+}
+
+EXPORT_SYMBOL(nftnl_chain_unset);
+void nftnl_chain_unset(struct nftnl_chain *c, uint16_t attr)
+{
+	int i;
+
+	if (!(c->flags & (1 << attr)))
+		return;
+
+	switch (attr) {
+	case NFTNL_CHAIN_NAME:
+		xfree(c->name);
+		break;
+	case NFTNL_CHAIN_TABLE:
+		xfree(c->table);
+		break;
+	case NFTNL_CHAIN_USE:
+		break;
+	case NFTNL_CHAIN_TYPE:
+		xfree(c->type);
+		break;
+	case NFTNL_CHAIN_HOOKNUM:
+	case NFTNL_CHAIN_PRIO:
+	case NFTNL_CHAIN_POLICY:
+	case NFTNL_CHAIN_BYTES:
+	case NFTNL_CHAIN_PACKETS:
+	case NFTNL_CHAIN_HANDLE:
+	case NFTNL_CHAIN_FAMILY:
+	case NFTNL_CHAIN_FLAGS:
+	case NFTNL_CHAIN_ID:
+		break;
+	case NFTNL_CHAIN_DEV:
+		xfree(c->dev);
+		break;
+	case NFTNL_CHAIN_DEVICES:
+		for (i = 0; i < c->dev_array_len; i++)
+			xfree(c->dev_array[i]);
+		xfree(c->dev_array);
+		break;
+	default:
+		return;
+	}
+
+	c->flags &= ~(1 << attr);
+}
+
+static uint32_t nftnl_chain_validate[NFTNL_CHAIN_MAX + 1] = {
+	[NFTNL_CHAIN_HOOKNUM]	= sizeof(uint32_t),
+	[NFTNL_CHAIN_PRIO]		= sizeof(int32_t),
+	[NFTNL_CHAIN_POLICY]		= sizeof(uint32_t),
+	[NFTNL_CHAIN_BYTES]		= sizeof(uint64_t),
+	[NFTNL_CHAIN_PACKETS]	= sizeof(uint64_t),
+	[NFTNL_CHAIN_HANDLE]		= sizeof(uint64_t),
+	[NFTNL_CHAIN_FAMILY]		= sizeof(uint32_t),
+	[NFTNL_CHAIN_FLAGS]		= sizeof(uint32_t),
+	[NFTNL_CHAIN_ID]		= sizeof(uint32_t),
+};
+
+EXPORT_SYMBOL(nftnl_chain_set_data);
+int nftnl_chain_set_data(struct nftnl_chain *c, uint16_t attr,
+			 const void *data, uint32_t data_len)
+{
+	const char **dev_array;
+	int len = 0, i;
+
+	nftnl_assert_attr_exists(attr, NFTNL_CHAIN_MAX);
+	nftnl_assert_validate(data, nftnl_chain_validate, attr, data_len);
+
+	switch(attr) {
+	case NFTNL_CHAIN_NAME:
+		if (c->flags & (1 << NFTNL_CHAIN_NAME))
+			xfree(c->name);
+
+		c->name = strdup(data);
+		if (!c->name)
+			return -1;
+		break;
+	case NFTNL_CHAIN_TABLE:
+		if (c->flags & (1 << NFTNL_CHAIN_TABLE))
+			xfree(c->table);
+
+		c->table = strdup(data);
+		if (!c->table)
+			return -1;
+		break;
+	case NFTNL_CHAIN_HOOKNUM:
+		memcpy(&c->hooknum, data, sizeof(c->hooknum));
+		break;
+	case NFTNL_CHAIN_PRIO:
+		memcpy(&c->prio, data, sizeof(c->prio));
+		break;
+	case NFTNL_CHAIN_POLICY:
+		memcpy(&c->policy, data, sizeof(c->policy));
+		break;
+	case NFTNL_CHAIN_USE:
+		memcpy(&c->use, data, sizeof(c->use));
+		break;
+	case NFTNL_CHAIN_BYTES:
+		memcpy(&c->bytes, data, sizeof(c->bytes));
+		break;
+	case NFTNL_CHAIN_PACKETS:
+		memcpy(&c->packets, data, sizeof(c->packets));
+		break;
+	case NFTNL_CHAIN_HANDLE:
+		memcpy(&c->handle, data, sizeof(c->handle));
+		break;
+	case NFTNL_CHAIN_FAMILY:
+		memcpy(&c->family, data, sizeof(c->family));
+		break;
+	case NFTNL_CHAIN_TYPE:
+		if (c->flags & (1 << NFTNL_CHAIN_TYPE))
+			xfree(c->type);
+
+		c->type = strdup(data);
+		if (!c->type)
+			return -1;
+		break;
+	case NFTNL_CHAIN_DEV:
+		if (c->flags & (1 << NFTNL_CHAIN_DEV))
+			xfree(c->dev);
+
+		c->dev = strdup(data);
+		if (!c->dev)
+			return -1;
+		break;
+	case NFTNL_CHAIN_DEVICES:
+		dev_array = (const char **)data;
+		while (dev_array[len] != NULL)
+			len++;
+
+		if (c->flags & (1 << NFTNL_CHAIN_DEVICES)) {
+			for (i = 0; i < c->dev_array_len; i++)
+				xfree(c->dev_array[i]);
+			xfree(c->dev_array);
+		}
+
+		c->dev_array = calloc(len + 1, sizeof(char *));
+		if (!c->dev_array)
+			return -1;
+
+		for (i = 0; i < len; i++)
+			c->dev_array[i] = strdup(dev_array[i]);
+
+		c->dev_array_len = len;
+		break;
+	case NFTNL_CHAIN_FLAGS:
+		memcpy(&c->chain_flags, data, sizeof(c->chain_flags));
+		break;
+	case NFTNL_CHAIN_ID:
+		memcpy(&c->chain_id, data, sizeof(c->chain_id));
+		break;
+	case NFTNL_CHAIN_USERDATA:
+		if (c->flags & (1 << NFTNL_CHAIN_USERDATA))
+			xfree(c->user.data);
+
+		c->user.data = malloc(data_len);
+		if (!c->user.data)
+			return -1;
+		memcpy(c->user.data, data, data_len);
+		c->user.len = data_len;
+		break;
+	}
+	c->flags |= (1 << attr);
+	return 0;
+}
+
+void nftnl_chain_set(struct nftnl_chain *c, uint16_t attr, const void *data) __visible;
+void nftnl_chain_set(struct nftnl_chain *c, uint16_t attr, const void *data)
+{
+	nftnl_chain_set_data(c, attr, data, nftnl_chain_validate[attr]);
+}
+
+EXPORT_SYMBOL(nftnl_chain_set_u32);
+void nftnl_chain_set_u32(struct nftnl_chain *c, uint16_t attr, uint32_t data)
+{
+	nftnl_chain_set_data(c, attr, &data, sizeof(uint32_t));
+}
+
+EXPORT_SYMBOL(nftnl_chain_set_s32);
+void nftnl_chain_set_s32(struct nftnl_chain *c, uint16_t attr, int32_t data)
+{
+	nftnl_chain_set_data(c, attr, &data, sizeof(int32_t));
+}
+
+EXPORT_SYMBOL(nftnl_chain_set_u64);
+void nftnl_chain_set_u64(struct nftnl_chain *c, uint16_t attr, uint64_t data)
+{
+	nftnl_chain_set_data(c, attr, &data, sizeof(uint64_t));
+}
+
+EXPORT_SYMBOL(nftnl_chain_set_u8);
+void nftnl_chain_set_u8(struct nftnl_chain *c, uint16_t attr, uint8_t data)
+{
+	nftnl_chain_set_data(c, attr, &data, sizeof(uint8_t));
+}
+
+EXPORT_SYMBOL(nftnl_chain_set_str);
+int nftnl_chain_set_str(struct nftnl_chain *c, uint16_t attr, const char *str)
+{
+	return nftnl_chain_set_data(c, attr, str, strlen(str) + 1);
+}
+
+EXPORT_SYMBOL(nftnl_chain_set_array);
+int nftnl_chain_set_array(struct nftnl_chain *c, uint16_t attr,
+			  const char **data)
+{
+	return nftnl_chain_set_data(c, attr, data, 0);
+}
+
+EXPORT_SYMBOL(nftnl_chain_get_data);
+const void *nftnl_chain_get_data(const struct nftnl_chain *c, uint16_t attr,
+				 uint32_t *data_len)
+{
+	if (!(c->flags & (1 << attr)))
+		return NULL;
+
+	switch(attr) {
+	case NFTNL_CHAIN_NAME:
+		*data_len = strlen(c->name) + 1;
+		return c->name;
+	case NFTNL_CHAIN_TABLE:
+		*data_len = strlen(c->table) + 1;
+		return c->table;
+	case NFTNL_CHAIN_HOOKNUM:
+		*data_len = sizeof(uint32_t);
+		return &c->hooknum;
+	case NFTNL_CHAIN_PRIO:
+		*data_len = sizeof(int32_t);
+		return &c->prio;
+	case NFTNL_CHAIN_POLICY:
+		*data_len = sizeof(uint32_t);
+		return &c->policy;
+	case NFTNL_CHAIN_USE:
+		*data_len = sizeof(uint32_t);
+		return &c->use;
+	case NFTNL_CHAIN_BYTES:
+		*data_len = sizeof(uint64_t);
+		return &c->bytes;
+	case NFTNL_CHAIN_PACKETS:
+		*data_len = sizeof(uint64_t);
+		return &c->packets;
+	case NFTNL_CHAIN_HANDLE:
+		*data_len = sizeof(uint64_t);
+		return &c->handle;
+	case NFTNL_CHAIN_FAMILY:
+		*data_len = sizeof(uint32_t);
+		return &c->family;
+	case NFTNL_CHAIN_TYPE:
+		*data_len = sizeof(uint32_t);
+		return c->type;
+	case NFTNL_CHAIN_DEV:
+		*data_len = strlen(c->dev) + 1;
+		return c->dev;
+	case NFTNL_CHAIN_DEVICES:
+		*data_len = 0;
+		return &c->dev_array[0];
+	case NFTNL_CHAIN_FLAGS:
+		*data_len = sizeof(uint32_t);
+		return &c->chain_flags;
+	case NFTNL_CHAIN_ID:
+		*data_len = sizeof(uint32_t);
+		return &c->chain_id;
+	case NFTNL_CHAIN_USERDATA:
+		*data_len = c->user.len;
+		return c->user.data;
+	}
+	return NULL;
+}
+
+EXPORT_SYMBOL(nftnl_chain_get);
+const void *nftnl_chain_get(const struct nftnl_chain *c, uint16_t attr)
+{
+	uint32_t data_len;
+	return nftnl_chain_get_data(c, attr, &data_len);
+}
+
+EXPORT_SYMBOL(nftnl_chain_get_str);
+const char *nftnl_chain_get_str(const struct nftnl_chain *c, uint16_t attr)
+{
+	return nftnl_chain_get(c, attr);
+}
+
+EXPORT_SYMBOL(nftnl_chain_get_u32);
+uint32_t nftnl_chain_get_u32(const struct nftnl_chain *c, uint16_t attr)
+{
+	uint32_t data_len;
+	const uint32_t *val = nftnl_chain_get_data(c, attr, &data_len);
+
+	nftnl_assert(val, attr, data_len == sizeof(uint32_t));
+
+	return val ? *val : 0;
+}
+
+EXPORT_SYMBOL(nftnl_chain_get_s32);
+int32_t nftnl_chain_get_s32(const struct nftnl_chain *c, uint16_t attr)
+{
+	uint32_t data_len;
+	const int32_t *val = nftnl_chain_get_data(c, attr, &data_len);
+
+	nftnl_assert(val, attr, data_len == sizeof(int32_t));
+
+	return val ? *val : 0;
+}
+
+EXPORT_SYMBOL(nftnl_chain_get_u64);
+uint64_t nftnl_chain_get_u64(const struct nftnl_chain *c, uint16_t attr)
+{
+	uint32_t data_len;
+	const uint64_t *val = nftnl_chain_get_data(c, attr, &data_len);
+
+	nftnl_assert(val, attr, data_len == sizeof(int64_t));
+
+	return val ? *val : 0;
+}
+
+EXPORT_SYMBOL(nftnl_chain_get_u8);
+uint8_t nftnl_chain_get_u8(const struct nftnl_chain *c, uint16_t attr)
+{
+	uint32_t data_len;
+	const uint8_t *val = nftnl_chain_get_data(c, attr, &data_len);
+
+	nftnl_assert(val, attr, data_len == sizeof(int8_t));
+
+	return val ? *val : 0;
+}
+
+EXPORT_SYMBOL(nftnl_chain_get_array);
+const char *const *nftnl_chain_get_array(const struct nftnl_chain *c, uint16_t attr)
+{
+	uint32_t data_len;
+	const char * const *val = nftnl_chain_get_data(c, attr, &data_len);
+
+	nftnl_assert(val, attr, attr == NFTNL_CHAIN_DEVICES);
+
+	return val;
+}
+
+EXPORT_SYMBOL(nftnl_chain_nlmsg_build_payload);
+void nftnl_chain_nlmsg_build_payload(struct nlmsghdr *nlh, const struct nftnl_chain *c)
+{
+	struct nlattr *nest = NULL;
+	int i;
+
+	if (c->flags & (1 << NFTNL_CHAIN_TABLE))
+		mnl_attr_put_strz(nlh, NFTA_CHAIN_TABLE, c->table);
+	if (c->flags & (1 << NFTNL_CHAIN_NAME))
+		mnl_attr_put_strz(nlh, NFTA_CHAIN_NAME, c->name);
+
+	if ((c->flags & (1 << NFTNL_CHAIN_HOOKNUM)) ||
+	    (c->flags & (1 << NFTNL_CHAIN_PRIO)) ||
+	    (c->flags & (1 << NFTNL_CHAIN_DEV)) ||
+	    (c->flags & (1 << NFTNL_CHAIN_DEVICES)))
+		nest = mnl_attr_nest_start(nlh, NFTA_CHAIN_HOOK);
+
+	if ((c->flags & (1 << NFTNL_CHAIN_HOOKNUM)))
+		mnl_attr_put_u32(nlh, NFTA_HOOK_HOOKNUM, htonl(c->hooknum));
+	if ((c->flags & (1 << NFTNL_CHAIN_PRIO)))
+		mnl_attr_put_u32(nlh, NFTA_HOOK_PRIORITY, htonl(c->prio));
+
+	if (c->flags & (1 << NFTNL_CHAIN_DEV))
+		mnl_attr_put_strz(nlh, NFTA_HOOK_DEV, c->dev);
+	else if (c->flags & (1 << NFTNL_CHAIN_DEVICES)) {
+		struct nlattr *nest_dev;
+
+		nest_dev = mnl_attr_nest_start(nlh, NFTA_HOOK_DEVS);
+		for (i = 0; i < c->dev_array_len; i++)
+			mnl_attr_put_strz(nlh, NFTA_DEVICE_NAME,
+					  c->dev_array[i]);
+		mnl_attr_nest_end(nlh, nest_dev);
+	}
+
+	if ((c->flags & (1 << NFTNL_CHAIN_HOOKNUM)) ||
+	    (c->flags & (1 << NFTNL_CHAIN_PRIO)) ||
+	    (c->flags & (1 << NFTNL_CHAIN_DEV)) ||
+	    (c->flags & (1 << NFTNL_CHAIN_DEVICES)))
+		mnl_attr_nest_end(nlh, nest);
+
+	if (c->flags & (1 << NFTNL_CHAIN_POLICY))
+		mnl_attr_put_u32(nlh, NFTA_CHAIN_POLICY, htonl(c->policy));
+	if (c->flags & (1 << NFTNL_CHAIN_USE))
+		mnl_attr_put_u32(nlh, NFTA_CHAIN_USE, htonl(c->use));
+	if ((c->flags & (1 << NFTNL_CHAIN_PACKETS)) &&
+	    (c->flags & (1 << NFTNL_CHAIN_BYTES))) {
+		nest = mnl_attr_nest_start(nlh, NFTA_CHAIN_COUNTERS);
+		mnl_attr_put_u64(nlh, NFTA_COUNTER_PACKETS, be64toh(c->packets));
+		mnl_attr_put_u64(nlh, NFTA_COUNTER_BYTES, be64toh(c->bytes));
+		mnl_attr_nest_end(nlh, nest);
+	}
+	if (c->flags & (1 << NFTNL_CHAIN_HANDLE))
+		mnl_attr_put_u64(nlh, NFTA_CHAIN_HANDLE, be64toh(c->handle));
+	if (c->flags & (1 << NFTNL_CHAIN_TYPE))
+		mnl_attr_put_strz(nlh, NFTA_CHAIN_TYPE, c->type);
+	if (c->flags & (1 << NFTNL_CHAIN_FLAGS))
+		mnl_attr_put_u32(nlh, NFTA_CHAIN_FLAGS, htonl(c->chain_flags));
+	if (c->flags & (1 << NFTNL_CHAIN_ID))
+		mnl_attr_put_u32(nlh, NFTA_CHAIN_ID, htonl(c->chain_id));
+	if (c->flags & (1 << NFTNL_CHAIN_USERDATA))
+		mnl_attr_put(nlh, NFTA_CHAIN_USERDATA, c->user.len, c->user.data);
+}
+
+EXPORT_SYMBOL(nftnl_chain_rule_add);
+void nftnl_chain_rule_add(struct nftnl_rule *rule, struct nftnl_chain *c)
+{
+	list_add(&rule->head, &c->rule_list);
+}
+
+EXPORT_SYMBOL(nftnl_chain_rule_del);
+void nftnl_chain_rule_del(struct nftnl_rule *r)
+{
+	list_del(&r->head);
+}
+
+EXPORT_SYMBOL(nftnl_chain_rule_add_tail);
+void nftnl_chain_rule_add_tail(struct nftnl_rule *rule, struct nftnl_chain *c)
+{
+	list_add_tail(&rule->head, &c->rule_list);
+}
+
+EXPORT_SYMBOL(nftnl_chain_rule_insert_at);
+void nftnl_chain_rule_insert_at(struct nftnl_rule *rule, struct nftnl_rule *pos)
+{
+	list_add_tail(&rule->head, &pos->head);
+}
+
+EXPORT_SYMBOL(nftnl_chain_rule_append_at);
+void nftnl_chain_rule_append_at(struct nftnl_rule *rule, struct nftnl_rule *pos)
+{
+	list_add(&rule->head, &pos->head);
+}
+
+static int nftnl_chain_parse_attr_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_CHAIN_MAX) < 0)
+		return MNL_CB_OK;
+
+	switch(type) {
+	case NFTA_CHAIN_NAME:
+	case NFTA_CHAIN_TABLE:
+	case NFTA_CHAIN_TYPE:
+		if (mnl_attr_validate(attr, MNL_TYPE_STRING) < 0)
+			abi_breakage();
+		break;
+	case NFTA_CHAIN_HOOK:
+	case NFTA_CHAIN_COUNTERS:
+		if (mnl_attr_validate(attr, MNL_TYPE_NESTED) < 0)
+			abi_breakage();
+		break;
+	case NFTA_CHAIN_POLICY:
+	case NFTA_CHAIN_USE:
+	case NFTA_CHAIN_FLAGS:
+	case NFTA_CHAIN_ID:
+		if (mnl_attr_validate(attr, MNL_TYPE_U32) < 0)
+			abi_breakage();
+		break;
+	case NFTA_CHAIN_HANDLE:
+		if (mnl_attr_validate(attr, MNL_TYPE_U64) < 0)
+			abi_breakage();
+		break;
+	case NFTA_CHAIN_USERDATA:
+		if (mnl_attr_validate(attr, MNL_TYPE_BINARY) < 0)
+			abi_breakage();
+		break;
+	}
+
+	tb[type] = attr;
+	return MNL_CB_OK;
+}
+
+static int nftnl_chain_parse_counters_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)
+			abi_breakage();
+		break;
+	}
+
+	tb[type] = attr;
+	return MNL_CB_OK;
+}
+
+static int nftnl_chain_parse_counters(struct nlattr *attr, struct nftnl_chain *c)
+{
+	struct nlattr *tb[NFTA_COUNTER_MAX+1] = {};
+
+	if (mnl_attr_parse_nested(attr, nftnl_chain_parse_counters_cb, tb) < 0)
+		return -1;
+
+	if (tb[NFTA_COUNTER_PACKETS]) {
+		c->packets = be64toh(mnl_attr_get_u64(tb[NFTA_COUNTER_PACKETS]));
+		c->flags |= (1 << NFTNL_CHAIN_PACKETS);
+	}
+	if (tb[NFTA_COUNTER_BYTES]) {
+		c->bytes = be64toh(mnl_attr_get_u64(tb[NFTA_COUNTER_BYTES]));
+		c->flags |= (1 << NFTNL_CHAIN_BYTES);
+	}
+
+	return 0;
+}
+
+static int nftnl_chain_parse_hook_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_HOOK_MAX) < 0)
+		return MNL_CB_OK;
+
+	switch(type) {
+	case NFTA_HOOK_HOOKNUM:
+	case NFTA_HOOK_PRIORITY:
+		if (mnl_attr_validate(attr, MNL_TYPE_U32) < 0)
+			abi_breakage();
+		break;
+	case NFTA_HOOK_DEV:
+		if (mnl_attr_validate(attr, MNL_TYPE_STRING) < 0)
+			abi_breakage();
+		break;
+	}
+
+	tb[type] = attr;
+	return MNL_CB_OK;
+}
+
+static int nftnl_chain_parse_devs(struct nlattr *nest, struct nftnl_chain *c)
+{
+	const char **dev_array, **tmp;
+	int len = 0, size = 8;
+	struct nlattr *attr;
+
+	dev_array = calloc(8, sizeof(char *));
+	if (!dev_array)
+		return -1;
+
+	mnl_attr_for_each_nested(attr, nest) {
+		if (mnl_attr_get_type(attr) != NFTA_DEVICE_NAME)
+			goto err;
+		dev_array[len++] = strdup(mnl_attr_get_str(attr));
+		if (len >= size) {
+			tmp = realloc(dev_array, size * 2 * sizeof(char *));
+			if (!tmp)
+				goto err;
+
+			size *= 2;
+			memset(&tmp[len], 0, (size - len) * sizeof(char *));
+			dev_array = tmp;
+		}
+	}
+
+	c->dev_array = dev_array;
+	c->dev_array_len = len;
+
+	return 0;
+err:
+	while (len--)
+		xfree(dev_array[len]);
+	xfree(dev_array);
+	return -1;
+}
+
+static int nftnl_chain_parse_hook(struct nlattr *attr, struct nftnl_chain *c)
+{
+	struct nlattr *tb[NFTA_HOOK_MAX+1] = {};
+	int ret;
+
+	if (mnl_attr_parse_nested(attr, nftnl_chain_parse_hook_cb, tb) < 0)
+		return -1;
+
+	if (tb[NFTA_HOOK_HOOKNUM]) {
+		c->hooknum = ntohl(mnl_attr_get_u32(tb[NFTA_HOOK_HOOKNUM]));
+		c->flags |= (1 << NFTNL_CHAIN_HOOKNUM);
+	}
+	if (tb[NFTA_HOOK_PRIORITY]) {
+		c->prio = ntohl(mnl_attr_get_u32(tb[NFTA_HOOK_PRIORITY]));
+		c->flags |= (1 << NFTNL_CHAIN_PRIO);
+	}
+	if (tb[NFTA_HOOK_DEV]) {
+		c->dev = strdup(mnl_attr_get_str(tb[NFTA_HOOK_DEV]));
+		if (!c->dev)
+			return -1;
+		c->flags |= (1 << NFTNL_CHAIN_DEV);
+	}
+	if (tb[NFTA_HOOK_DEVS]) {
+		ret = nftnl_chain_parse_devs(tb[NFTA_HOOK_DEVS], c);
+		if (ret < 0)
+			return -1;
+		c->flags |= (1 << NFTNL_CHAIN_DEVICES);
+	}
+
+	return 0;
+}
+
+EXPORT_SYMBOL(nftnl_chain_nlmsg_parse);
+int nftnl_chain_nlmsg_parse(const struct nlmsghdr *nlh, struct nftnl_chain *c)
+{
+	struct nlattr *tb[NFTA_CHAIN_MAX+1] = {};
+	struct nfgenmsg *nfg = mnl_nlmsg_get_payload(nlh);
+	int ret = 0;
+
+	if (mnl_attr_parse(nlh, sizeof(*nfg), nftnl_chain_parse_attr_cb, tb) < 0)
+		return -1;
+
+	if (tb[NFTA_CHAIN_NAME]) {
+		if (c->flags & (1 << NFTNL_CHAIN_NAME))
+			xfree(c->name);
+		c->name = strdup(mnl_attr_get_str(tb[NFTA_CHAIN_NAME]));
+		if (!c->name)
+			return -1;
+		c->flags |= (1 << NFTNL_CHAIN_NAME);
+	}
+	if (tb[NFTA_CHAIN_TABLE]) {
+		if (c->flags & (1 << NFTNL_CHAIN_TABLE))
+			xfree(c->table);
+		c->table = strdup(mnl_attr_get_str(tb[NFTA_CHAIN_TABLE]));
+		if (!c->table)
+			return -1;
+		c->flags |= (1 << NFTNL_CHAIN_TABLE);
+	}
+	if (tb[NFTA_CHAIN_HOOK]) {
+		ret = nftnl_chain_parse_hook(tb[NFTA_CHAIN_HOOK], c);
+		if (ret < 0)
+			return ret;
+	}
+	if (tb[NFTA_CHAIN_POLICY]) {
+		c->policy = ntohl(mnl_attr_get_u32(tb[NFTA_CHAIN_POLICY]));
+		c->flags |= (1 << NFTNL_CHAIN_POLICY);
+	}
+	if (tb[NFTA_CHAIN_USE]) {
+		c->use = ntohl(mnl_attr_get_u32(tb[NFTA_CHAIN_USE]));
+		c->flags |= (1 << NFTNL_CHAIN_USE);
+	}
+	if (tb[NFTA_CHAIN_COUNTERS]) {
+		ret = nftnl_chain_parse_counters(tb[NFTA_CHAIN_COUNTERS], c);
+		if (ret < 0)
+			return ret;
+	}
+	if (tb[NFTA_CHAIN_HANDLE]) {
+		c->handle = be64toh(mnl_attr_get_u64(tb[NFTA_CHAIN_HANDLE]));
+		c->flags |= (1 << NFTNL_CHAIN_HANDLE);
+	}
+	if (tb[NFTA_CHAIN_TYPE]) {
+		if (c->flags & (1 << NFTNL_CHAIN_TYPE))
+			xfree(c->type);
+		c->type = strdup(mnl_attr_get_str(tb[NFTA_CHAIN_TYPE]));
+		if (!c->type)
+			return -1;
+		c->flags |= (1 << NFTNL_CHAIN_TYPE);
+	}
+	if (tb[NFTA_CHAIN_FLAGS]) {
+		c->chain_flags = ntohl(mnl_attr_get_u32(tb[NFTA_CHAIN_FLAGS]));
+		c->flags |= (1 << NFTNL_CHAIN_FLAGS);
+	}
+	if (tb[NFTA_CHAIN_ID]) {
+		c->chain_id = ntohl(mnl_attr_get_u32(tb[NFTA_CHAIN_ID]));
+		c->flags |= (1 << NFTNL_CHAIN_ID);
+	}
+	if (tb[NFTA_CHAIN_USERDATA]) {
+		nftnl_chain_set_data(c, NFTNL_CHAIN_USERDATA,
+				     mnl_attr_get_payload(tb[NFTA_CHAIN_USERDATA]),
+				     mnl_attr_get_payload_len(tb[NFTA_CHAIN_USERDATA]));
+	}
+
+	c->family = nfg->nfgen_family;
+	c->flags |= (1 << NFTNL_CHAIN_FAMILY);
+
+	return ret;
+}
+
+static inline int nftnl_str2hooknum(int family, const char *hook)
+{
+	int hooknum;
+
+	for (hooknum = 0; hooknum < NF_INET_NUMHOOKS; hooknum++) {
+		if (strcmp(hook, nftnl_hooknum2str(family, hooknum)) == 0)
+			return hooknum;
+	}
+	return -1;
+}
+
+static int nftnl_chain_snprintf_default(char *buf, size_t remain,
+					const struct nftnl_chain *c)
+{
+	int ret, offset = 0, i;
+
+	ret = snprintf(buf, remain, "%s %s %s use %u",
+		       nftnl_family2str(c->family), c->table, c->name, c->use);
+	SNPRINTF_BUFFER_SIZE(ret, remain, offset);
+
+	if (c->flags & (1 << NFTNL_CHAIN_HOOKNUM)) {
+		ret = snprintf(buf + offset, remain, " type %s hook %s prio %d",
+			       c->type, nftnl_hooknum2str(c->family, c->hooknum),
+			       c->prio);
+		SNPRINTF_BUFFER_SIZE(ret, remain, offset);
+
+		if (c->flags & (1 << NFTNL_CHAIN_POLICY)) {
+			ret = snprintf(buf + offset, remain, " policy %s",
+				       nftnl_verdict2str(c->policy));
+			SNPRINTF_BUFFER_SIZE(ret, remain, offset);
+		}
+
+		ret = snprintf(buf + offset, remain,
+			       " packets %"PRIu64" bytes %"PRIu64"",
+			       c->packets, c->bytes);
+		SNPRINTF_BUFFER_SIZE(ret, remain, offset);
+
+		if (c->flags & (1 << NFTNL_CHAIN_DEV)) {
+			ret = snprintf(buf + offset, remain, " dev %s ",
+				       c->dev);
+			SNPRINTF_BUFFER_SIZE(ret, remain, offset);
+		}
+		if (c->flags & (1 << NFTNL_CHAIN_DEVICES)) {
+			ret = snprintf(buf + offset, remain, " dev { ");
+			SNPRINTF_BUFFER_SIZE(ret, remain, offset);
+
+			for (i = 0; i < c->dev_array_len; i++) {
+				ret = snprintf(buf + offset, remain, " %s ",
+					       c->dev_array[i]);
+				SNPRINTF_BUFFER_SIZE(ret, remain, offset);
+			}
+			ret = snprintf(buf + offset, remain, " } ");
+			SNPRINTF_BUFFER_SIZE(ret, remain, offset);
+		}
+		if (c->flags & (1 << NFTNL_CHAIN_FLAGS)) {
+			ret = snprintf(buf + offset, remain, " flags %x",
+				       c->chain_flags);
+			SNPRINTF_BUFFER_SIZE(ret, remain, offset);
+		}
+		if (c->flags & (1 << NFTNL_CHAIN_ID)) {
+			ret = snprintf(buf + offset, remain, " id %x",
+				       c->chain_id);
+			SNPRINTF_BUFFER_SIZE(ret, remain, offset);
+		}
+	}
+
+	return offset;
+}
+
+static int nftnl_chain_cmd_snprintf(char *buf, size_t remain,
+				    const struct nftnl_chain *c, uint32_t cmd,
+				    uint32_t type, uint32_t flags)
+{
+	int ret, offset = 0;
+
+	if (type != NFTNL_OUTPUT_DEFAULT)
+		return -1;
+
+	ret = nftnl_chain_snprintf_default(buf + offset, remain, c);
+	SNPRINTF_BUFFER_SIZE(ret, remain, offset);
+	return offset;
+}
+
+EXPORT_SYMBOL(nftnl_chain_snprintf);
+int nftnl_chain_snprintf(char *buf, size_t size, const struct nftnl_chain *c,
+			 uint32_t type, uint32_t flags)
+{
+	if (size)
+		buf[0] = '\0';
+
+	return nftnl_chain_cmd_snprintf(buf, size, c, nftnl_flag2cmd(flags),
+					type, flags);
+}
+
+static int nftnl_chain_do_snprintf(char *buf, size_t size, const void *c,
+				   uint32_t cmd, uint32_t type, uint32_t flags)
+{
+	return nftnl_chain_snprintf(buf, size, c, type, flags);
+}
+
+EXPORT_SYMBOL(nftnl_chain_fprintf);
+int nftnl_chain_fprintf(FILE *fp, const struct nftnl_chain *c, uint32_t type,
+			uint32_t flags)
+{
+	return nftnl_fprintf(fp, c, NFTNL_CMD_UNSPEC, type, flags,
+			   nftnl_chain_do_snprintf);
+}
+
+EXPORT_SYMBOL(nftnl_rule_foreach);
+int nftnl_rule_foreach(struct nftnl_chain *c,
+                          int (*cb)(struct nftnl_rule *r, void *data),
+                          void *data)
+{
+       struct nftnl_rule *cur, *tmp;
+       int ret;
+
+       list_for_each_entry_safe(cur, tmp, &c->rule_list, head) {
+               ret = cb(cur, data);
+               if (ret < 0)
+                       return ret;
+       }
+       return 0;
+}
+
+EXPORT_SYMBOL(nftnl_rule_lookup_byindex);
+struct nftnl_rule *
+nftnl_rule_lookup_byindex(struct nftnl_chain *c, uint32_t index)
+{
+	struct nftnl_rule *r;
+
+	list_for_each_entry(r, &c->rule_list, head) {
+		if (!index)
+			return r;
+		index--;
+	}
+	return NULL;
+}
+
+struct nftnl_rule_iter {
+	const struct nftnl_chain	*c;
+	struct nftnl_rule		*cur;
+};
+
+static void nftnl_rule_iter_init(const struct nftnl_chain *c,
+				 struct nftnl_rule_iter *iter)
+{
+	iter->c = c;
+	if (list_empty(&c->rule_list))
+		iter->cur = NULL;
+	else
+		iter->cur = list_entry(c->rule_list.next, struct nftnl_rule,
+				       head);
+}
+
+EXPORT_SYMBOL(nftnl_rule_iter_create);
+struct nftnl_rule_iter *nftnl_rule_iter_create(const struct nftnl_chain *c)
+{
+	struct nftnl_rule_iter *iter;
+
+	iter = calloc(1, sizeof(struct nftnl_rule_iter));
+	if (iter == NULL)
+		return NULL;
+
+	nftnl_rule_iter_init(c, iter);
+
+	return iter;
+}
+
+EXPORT_SYMBOL(nftnl_rule_iter_next);
+struct nftnl_rule *nftnl_rule_iter_next(struct nftnl_rule_iter *iter)
+{
+	struct nftnl_rule *rule = iter->cur;
+
+	if (rule == NULL)
+		return NULL;
+
+	/* get next rule, if any */
+	iter->cur = list_entry(iter->cur->head.next, struct nftnl_rule, head);
+	if (&iter->cur->head == iter->c->rule_list.next)
+		return NULL;
+
+	return rule;
+}
+
+EXPORT_SYMBOL(nftnl_rule_iter_destroy);
+void nftnl_rule_iter_destroy(struct nftnl_rule_iter *iter)
+{
+	xfree(iter);
+}
+
+#define CHAIN_NAME_HSIZE	512
+
+struct nftnl_chain_list {
+
+	struct list_head list;
+	struct hlist_head name_hash[CHAIN_NAME_HSIZE];
+};
+
+EXPORT_SYMBOL(nftnl_chain_list_alloc);
+struct nftnl_chain_list *nftnl_chain_list_alloc(void)
+{
+	struct nftnl_chain_list *list;
+	int i;
+
+	list = calloc(1, sizeof(struct nftnl_chain_list));
+	if (list == NULL)
+		return NULL;
+
+	INIT_LIST_HEAD(&list->list);
+	for (i = 0; i < CHAIN_NAME_HSIZE; i++)
+		INIT_HLIST_HEAD(&list->name_hash[i]);
+
+	return list;
+}
+
+EXPORT_SYMBOL(nftnl_chain_list_free);
+void nftnl_chain_list_free(struct nftnl_chain_list *list)
+{
+	struct nftnl_chain *r, *tmp;
+
+	list_for_each_entry_safe(r, tmp, &list->list, head) {
+		list_del(&r->head);
+		hlist_del(&r->hnode);
+		nftnl_chain_free(r);
+	}
+	xfree(list);
+}
+
+EXPORT_SYMBOL(nftnl_chain_list_is_empty);
+int nftnl_chain_list_is_empty(const struct nftnl_chain_list *list)
+{
+	return list_empty(&list->list);
+}
+
+static uint32_t djb_hash(const char *key)
+{
+	uint32_t i, hash = 5381;
+
+	for (i = 0; i < strlen(key); i++)
+		hash = ((hash << 5) + hash) + key[i];
+
+	return hash;
+}
+
+EXPORT_SYMBOL(nftnl_chain_list_add);
+void nftnl_chain_list_add(struct nftnl_chain *r, struct nftnl_chain_list *list)
+{
+	int key = djb_hash(r->name) % CHAIN_NAME_HSIZE;
+
+	hlist_add_head(&r->hnode, &list->name_hash[key]);
+	list_add(&r->head, &list->list);
+}
+
+EXPORT_SYMBOL(nftnl_chain_list_add_tail);
+void nftnl_chain_list_add_tail(struct nftnl_chain *r, struct nftnl_chain_list *list)
+{
+	int key = djb_hash(r->name) % CHAIN_NAME_HSIZE;
+
+	hlist_add_head(&r->hnode, &list->name_hash[key]);
+	list_add_tail(&r->head, &list->list);
+}
+
+EXPORT_SYMBOL(nftnl_chain_list_del);
+void nftnl_chain_list_del(struct nftnl_chain *r)
+{
+	list_del(&r->head);
+	hlist_del(&r->hnode);
+}
+
+EXPORT_SYMBOL(nftnl_chain_list_foreach);
+int nftnl_chain_list_foreach(struct nftnl_chain_list *chain_list,
+			   int (*cb)(struct nftnl_chain *r, void *data),
+			   void *data)
+{
+	struct nftnl_chain *cur, *tmp;
+	int ret;
+
+	list_for_each_entry_safe(cur, tmp, &chain_list->list, head) {
+		ret = cb(cur, data);
+		if (ret < 0)
+			return ret;
+	}
+	return 0;
+}
+
+EXPORT_SYMBOL(nftnl_chain_list_lookup_byname);
+struct nftnl_chain *
+nftnl_chain_list_lookup_byname(struct nftnl_chain_list *chain_list,
+			       const char *chain)
+{
+	int key = djb_hash(chain) % CHAIN_NAME_HSIZE;
+	struct nftnl_chain *c;
+	struct hlist_node *n;
+
+	hlist_for_each_entry(c, n, &chain_list->name_hash[key], hnode) {
+		if (!strcmp(chain, c->name))
+			return c;
+	}
+	return NULL;
+}
+
+struct nftnl_chain_list_iter {
+	const struct nftnl_chain_list	*list;
+	struct nftnl_chain		*cur;
+};
+
+EXPORT_SYMBOL(nftnl_chain_list_iter_create);
+struct nftnl_chain_list_iter *
+nftnl_chain_list_iter_create(const struct nftnl_chain_list *l)
+{
+	struct nftnl_chain_list_iter *iter;
+
+	iter = calloc(1, sizeof(struct nftnl_chain_list_iter));
+	if (iter == NULL)
+		return NULL;
+
+	iter->list = l;
+	if (nftnl_chain_list_is_empty(l))
+		iter->cur = NULL;
+	else
+		iter->cur = list_entry(l->list.next, struct nftnl_chain, head);
+
+	return iter;
+}
+
+EXPORT_SYMBOL(nftnl_chain_list_iter_next);
+struct nftnl_chain *nftnl_chain_list_iter_next(struct nftnl_chain_list_iter *iter)
+{
+	struct nftnl_chain *r = iter->cur;
+
+	if (r == NULL)
+		return NULL;
+
+	/* get next chain, if any */
+	iter->cur = list_entry(iter->cur->head.next, struct nftnl_chain, head);
+	if (&iter->cur->head == iter->list->list.next)
+		return NULL;
+
+	return r;
+}
+
+EXPORT_SYMBOL(nftnl_chain_list_iter_destroy);
+void nftnl_chain_list_iter_destroy(struct nftnl_chain_list_iter *iter)
+{
+	xfree(iter);
+}