[linux-2.6-block.git] / net / netfilter / nft_meta.c

/*
 * Copyright (c) 2008-2009 Patrick McHardy <kaber@trash.net>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 * Development of this code funded by Astaro AG (http://www.astaro.com/)
 */

#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/netlink.h>
#include <linux/netfilter.h>
#include <linux/netfilter/nf_tables.h>
#include <net/dst.h>
#include <net/sock.h>
#include <net/tcp_states.h> /* for TCP_TIME_WAIT */
#include <net/netfilter/nf_tables.h>
#include <net/netfilter/nft_meta.h>

void nft_meta_get_eval(const struct nft_expr *expr,
		       struct nft_data data[NFT_REG_MAX + 1],
		       const struct nft_pktinfo *pkt)
{
	const struct nft_meta *priv = nft_expr_priv(expr);
	const struct sk_buff *skb = pkt->skb;
	const struct net_device *in = pkt->in, *out = pkt->out;
	struct nft_data *dest = &data[priv->dreg];

	switch (priv->key) {
	case NFT_META_LEN:
		dest->data[0] = skb->len;
		break;
	case NFT_META_PROTOCOL:
		*(__be16 *)dest->data = skb->protocol;
		break;
	case NFT_META_NFPROTO:
		dest->data[0] = pkt->ops->pf;
		break;
	case NFT_META_L4PROTO:
		dest->data[0] = pkt->tprot;
		break;
	case NFT_META_PRIORITY:
		dest->data[0] = skb->priority;
		break;
	case NFT_META_MARK:
		dest->data[0] = skb->mark;
		break;
	case NFT_META_IIF:
		if (in == NULL)
			goto err;
		dest->data[0] = in->ifindex;
		break;
	case NFT_META_OIF:
		if (out == NULL)
			goto err;
		dest->data[0] = out->ifindex;
		break;
	case NFT_META_IIFNAME:
		if (in == NULL)
			goto err;
		strncpy((char *)dest->data, in->name, sizeof(dest->data));
		break;
	case NFT_META_OIFNAME:
		if (out == NULL)
			goto err;
		strncpy((char *)dest->data, out->name, sizeof(dest->data));
		break;
	case NFT_META_IIFTYPE:
		if (in == NULL)
			goto err;
		*(u16 *)dest->data = in->type;
		break;
	case NFT_META_OIFTYPE:
		if (out == NULL)
			goto err;
		*(u16 *)dest->data = out->type;
		break;
	case NFT_META_SKUID:
		if (skb->sk == NULL || skb->sk->sk_state == TCP_TIME_WAIT)
			goto err;

		read_lock_bh(&skb->sk->sk_callback_lock);
		if (skb->sk->sk_socket == NULL ||
		    skb->sk->sk_socket->file == NULL) {
			read_unlock_bh(&skb->sk->sk_callback_lock);
			goto err;
		}

		dest->data[0] =
			from_kuid_munged(&init_user_ns,
				skb->sk->sk_socket->file->f_cred->fsuid);
		read_unlock_bh(&skb->sk->sk_callback_lock);
		break;
	case NFT_META_SKGID:
		if (skb->sk == NULL || skb->sk->sk_state == TCP_TIME_WAIT)
			goto err;

		read_lock_bh(&skb->sk->sk_callback_lock);
		if (skb->sk->sk_socket == NULL ||
		    skb->sk->sk_socket->file == NULL) {
			read_unlock_bh(&skb->sk->sk_callback_lock);
			goto err;
		}
		dest->data[0] =
			from_kgid_munged(&init_user_ns,
				 skb->sk->sk_socket->file->f_cred->fsgid);
		read_unlock_bh(&skb->sk->sk_callback_lock);
		break;
#ifdef CONFIG_IP_ROUTE_CLASSID
	case NFT_META_RTCLASSID: {
		const struct dst_entry *dst = skb_dst(skb);

		if (dst == NULL)
			goto err;
		dest->data[0] = dst->tclassid;
		break;
	}
#endif
#ifdef CONFIG_NETWORK_SECMARK
	case NFT_META_SECMARK:
		dest->data[0] = skb->secmark;
		break;
#endif
	default:
		WARN_ON(1);
		goto err;
	}
	return;

err:
	data[NFT_REG_VERDICT].verdict = NFT_BREAK;
}
EXPORT_SYMBOL_GPL(nft_meta_get_eval);

void nft_meta_set_eval(const struct nft_expr *expr,
		       struct nft_data data[NFT_REG_MAX + 1],
		       const struct nft_pktinfo *pkt)
{
	const struct nft_meta *meta = nft_expr_priv(expr);
	struct sk_buff *skb = pkt->skb;
	u32 value = data[meta->sreg].data[0];

	switch (meta->key) {
	case NFT_META_MARK:
		skb->mark = value;
		break;
	case NFT_META_PRIORITY:
		skb->priority = value;
		break;
	case NFT_META_NFTRACE:
		skb->nf_trace = 1;
		break;
	default:
		WARN_ON(1);
	}
}
EXPORT_SYMBOL_GPL(nft_meta_set_eval);

const struct nla_policy nft_meta_policy[NFTA_META_MAX + 1] = {
	[NFTA_META_DREG]	= { .type = NLA_U32 },
	[NFTA_META_KEY]		= { .type = NLA_U32 },
	[NFTA_META_SREG]	= { .type = NLA_U32 },
};
EXPORT_SYMBOL_GPL(nft_meta_policy);

int nft_meta_get_init(const struct nft_ctx *ctx,
		      const struct nft_expr *expr,
		      const struct nlattr * const tb[])
{
	struct nft_meta *priv = nft_expr_priv(expr);
	int err;

	priv->key = ntohl(nla_get_be32(tb[NFTA_META_KEY]));
	switch (priv->key) {
	case NFT_META_LEN:
	case NFT_META_PROTOCOL:
	case NFT_META_NFPROTO:
	case NFT_META_L4PROTO:
	case NFT_META_PRIORITY:
	case NFT_META_MARK:
	case NFT_META_IIF:
	case NFT_META_OIF:
	case NFT_META_IIFNAME:
	case NFT_META_OIFNAME:
	case NFT_META_IIFTYPE:
	case NFT_META_OIFTYPE:
	case NFT_META_SKUID:
	case NFT_META_SKGID:
#ifdef CONFIG_IP_ROUTE_CLASSID
	case NFT_META_RTCLASSID:
#endif
#ifdef CONFIG_NETWORK_SECMARK
	case NFT_META_SECMARK:
#endif
		break;
	default:
		return -EOPNOTSUPP;
	}

	priv->dreg = ntohl(nla_get_be32(tb[NFTA_META_DREG]));
	err = nft_validate_output_register(priv->dreg);
	if (err < 0)
		return err;

	err = nft_validate_data_load(ctx, priv->dreg, NULL, NFT_DATA_VALUE);
	if (err < 0)
		return err;

	return 0;
}
EXPORT_SYMBOL_GPL(nft_meta_get_init);

int nft_meta_set_init(const struct nft_ctx *ctx,
		      const struct nft_expr *expr,
		      const struct nlattr * const tb[])
{
	struct nft_meta *priv = nft_expr_priv(expr);
	int err;

	priv->key = ntohl(nla_get_be32(tb[NFTA_META_KEY]));
	switch (priv->key) {
	case NFT_META_MARK:
	case NFT_META_PRIORITY:
	case NFT_META_NFTRACE:
		break;
	default:
		return -EOPNOTSUPP;
	}

	priv->sreg = ntohl(nla_get_be32(tb[NFTA_META_SREG]));
	err = nft_validate_input_register(priv->sreg);
	if (err < 0)
		return err;

	return 0;
}
EXPORT_SYMBOL_GPL(nft_meta_set_init);

int nft_meta_get_dump(struct sk_buff *skb,
		      const struct nft_expr *expr)
{
	const struct nft_meta *priv = nft_expr_priv(expr);

	if (nla_put_be32(skb, NFTA_META_KEY, htonl(priv->key)))
		goto nla_put_failure;
	if (nla_put_be32(skb, NFTA_META_DREG, htonl(priv->dreg)))
		goto nla_put_failure;
	return 0;

nla_put_failure:
	return -1;
}
EXPORT_SYMBOL_GPL(nft_meta_get_dump);

int nft_meta_set_dump(struct sk_buff *skb,
		      const struct nft_expr *expr)
{
	const struct nft_meta *priv = nft_expr_priv(expr);

	if (nla_put_be32(skb, NFTA_META_KEY, htonl(priv->key)))
		goto nla_put_failure;
	if (nla_put_be32(skb, NFTA_META_SREG, htonl(priv->sreg)))
		goto nla_put_failure;

	return 0;

nla_put_failure:
	return -1;
}
EXPORT_SYMBOL_GPL(nft_meta_set_dump);

static struct nft_expr_type nft_meta_type;
static const struct nft_expr_ops nft_meta_get_ops = {
	.type		= &nft_meta_type,
	.size		= NFT_EXPR_SIZE(sizeof(struct nft_meta)),
	.eval		= nft_meta_get_eval,
	.init		= nft_meta_get_init,
	.dump		= nft_meta_get_dump,
};

static const struct nft_expr_ops nft_meta_set_ops = {
	.type		= &nft_meta_type,
	.size		= NFT_EXPR_SIZE(sizeof(struct nft_meta)),
	.eval		= nft_meta_set_eval,
	.init		= nft_meta_set_init,
	.dump		= nft_meta_set_dump,
};

static const struct nft_expr_ops *
nft_meta_select_ops(const struct nft_ctx *ctx,
		    const struct nlattr * const tb[])
{
	if (tb[NFTA_META_KEY] == NULL)
		return ERR_PTR(-EINVAL);

	if (tb[NFTA_META_DREG] && tb[NFTA_META_SREG])
		return ERR_PTR(-EINVAL);

	if (tb[NFTA_META_DREG])
		return &nft_meta_get_ops;

	if (tb[NFTA_META_SREG])
		return &nft_meta_set_ops;

	return ERR_PTR(-EINVAL);
}

static struct nft_expr_type nft_meta_type __read_mostly = {
	.name		= "meta",
	.select_ops	= &nft_meta_select_ops,
	.policy		= nft_meta_policy,
	.maxattr	= NFTA_META_MAX,
	.owner		= THIS_MODULE,
};

static int __init nft_meta_module_init(void)
{
	return nft_register_expr(&nft_meta_type);
}

static void __exit nft_meta_module_exit(void)
{
	nft_unregister_expr(&nft_meta_type);
}

module_init(nft_meta_module_init);
module_exit(nft_meta_module_exit);

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>");
MODULE_ALIAS_NFT_EXPR("meta");
Commit	Line	Data
96518518	1	/*
ef1f7df9	2	* Copyright (c) 2008-2009 Patrick McHardy <kaber@trash.net>
96518518 PM	3	*
	4	* This program is free software; you can redistribute it and/or modify
	5	* it under the terms of the GNU General Public License version 2 as
	6	* published by the Free Software Foundation.
	7	*
	8	* Development of this code funded by Astaro AG (http://www.astaro.com/)
	9	*/
	10
	11	#include <linux/kernel.h>
	12	#include <linux/init.h>
	13	#include <linux/module.h>
	14	#include <linux/netlink.h>
	15	#include <linux/netfilter.h>
	16	#include <linux/netfilter/nf_tables.h>
	17	#include <net/dst.h>
	18	#include <net/sock.h>
	19	#include <net/tcp_states.h> /* for TCP_TIME_WAIT */
	20	#include <net/netfilter/nf_tables.h>
aa45660c	21	#include <net/netfilter/nft_meta.h>
96518518	22
aa45660c TB	23	void nft_meta_get_eval(const struct nft_expr *expr,
	24	struct nft_data data[NFT_REG_MAX + 1],
	25	const struct nft_pktinfo *pkt)
96518518 PM	26	{
	27	const struct nft_meta *priv = nft_expr_priv(expr);
	28	const struct sk_buff *skb = pkt->skb;
	29	const struct net_device in = pkt->in, out = pkt->out;
	30	struct nft_data *dest = &data[priv->dreg];
	31
	32	switch (priv->key) {
	33	case NFT_META_LEN:
	34	dest->data[0] = skb->len;
	35	break;
	36	case NFT_META_PROTOCOL:
	37	(__be16 )dest->data = skb->protocol;
	38	break;
124edfa9 PM	39	case NFT_META_NFPROTO:
	40	dest->data[0] = pkt->ops->pf;
	41	break;
4566bf27 PM	42	case NFT_META_L4PROTO:
	43	dest->data[0] = pkt->tprot;
	44	break;
96518518 PM	45	case NFT_META_PRIORITY:
	46	dest->data[0] = skb->priority;
	47	break;
	48	case NFT_META_MARK:
	49	dest->data[0] = skb->mark;
	50	break;
	51	case NFT_META_IIF:
	52	if (in == NULL)
	53	goto err;
	54	dest->data[0] = in->ifindex;
	55	break;
	56	case NFT_META_OIF:
	57	if (out == NULL)
	58	goto err;
	59	dest->data[0] = out->ifindex;
	60	break;
	61	case NFT_META_IIFNAME:
	62	if (in == NULL)
	63	goto err;
	64	strncpy((char *)dest->data, in->name, sizeof(dest->data));
	65	break;
	66	case NFT_META_OIFNAME:
	67	if (out == NULL)
	68	goto err;
	69	strncpy((char *)dest->data, out->name, sizeof(dest->data));
	70	break;
	71	case NFT_META_IIFTYPE:
	72	if (in == NULL)
	73	goto err;
	74	(u16 )dest->data = in->type;
	75	break;
	76	case NFT_META_OIFTYPE:
	77	if (out == NULL)
	78	goto err;
	79	(u16 )dest->data = out->type;
	80	break;
	81	case NFT_META_SKUID:
	82	if (skb->sk == NULL \|\| skb->sk->sk_state == TCP_TIME_WAIT)
	83	goto err;
	84
	85	read_lock_bh(&skb->sk->sk_callback_lock);
	86	if (skb->sk->sk_socket == NULL \|\|
	87	skb->sk->sk_socket->file == NULL) {
	88	read_unlock_bh(&skb->sk->sk_callback_lock);
	89	goto err;
	90	}
	91
	92	dest->data[0] =
	93	from_kuid_munged(&init_user_ns,
	94	skb->sk->sk_socket->file->f_cred->fsuid);
	95	read_unlock_bh(&skb->sk->sk_callback_lock);
	96	break;
	97	case NFT_META_SKGID:
	98	if (skb->sk == NULL \|\| skb->sk->sk_state == TCP_TIME_WAIT)
	99	goto err;
	100
	101	read_lock_bh(&skb->sk->sk_callback_lock);
	102	if (skb->sk->sk_socket == NULL \|\|
	103	skb->sk->sk_socket->file == NULL) {
	104	read_unlock_bh(&skb->sk->sk_callback_lock);
	105	goto err;
	106	}
	107	dest->data[0] =
	108	from_kgid_munged(&init_user_ns,
109	skb->sk->sk_socket->file->f_cred->fsgid);
110	read_unlock_bh(&skb->sk->sk_callback_lock);
111	break;
06efbd6d	112	#ifdef CONFIG_IP_ROUTE_CLASSID
96518518 PM	113	case NFT_META_RTCLASSID: {
	114	const struct dst_entry *dst = skb_dst(skb);
	115
	116	if (dst == NULL)
	117	goto err;
	118	dest->data[0] = dst->tclassid;
	119	break;
	120	}
	121	#endif
	122	#ifdef CONFIG_NETWORK_SECMARK
	123	case NFT_META_SECMARK:
	124	dest->data[0] = skb->secmark;
	125	break;
	126	#endif
	127	default:
	128	WARN_ON(1);
	129	goto err;
	130	}
	131	return;
	132
	133	err:
	134	data[NFT_REG_VERDICT].verdict = NFT_BREAK;
	135	}
aa45660c	136	EXPORT_SYMBOL_GPL(nft_meta_get_eval);
96518518	137
aa45660c TB	138	void nft_meta_set_eval(const struct nft_expr *expr,
	139	struct nft_data data[NFT_REG_MAX + 1],
	140	const struct nft_pktinfo *pkt)
e035b77a ABG	141	{
	142	const struct nft_meta *meta = nft_expr_priv(expr);
	143	struct sk_buff *skb = pkt->skb;
	144	u32 value = data[meta->sreg].data[0];
	145
	146	switch (meta->key) {
	147	case NFT_META_MARK:
	148	skb->mark = value;
	149	break;
	150	case NFT_META_PRIORITY:
	151	skb->priority = value;
	152	break;
	153	case NFT_META_NFTRACE:
	154	skb->nf_trace = 1;
	155	break;
	156	default:
	157	WARN_ON(1);
	158	}
	159	}
aa45660c	160	EXPORT_SYMBOL_GPL(nft_meta_set_eval);
e035b77a	161
aa45660c	162	const struct nla_policy nft_meta_policy[NFTA_META_MAX + 1] = {
96518518 PM	163	[NFTA_META_DREG] = { .type = NLA_U32 },
96518518 PM	164	[NFTA_META_KEY] = { .type = NLA_U32 },
e035b77a	165	[NFTA_META_SREG] = { .type = NLA_U32 },
96518518	166	};
aa45660c	167	EXPORT_SYMBOL_GPL(nft_meta_policy);
96518518	168
aa45660c TB	169	int nft_meta_get_init(const struct nft_ctx *ctx,
	170	const struct nft_expr *expr,
	171	const struct nlattr * const tb[])
96518518	172	{
d2caa696 PM	173	struct nft_meta *priv = nft_expr_priv(expr);
d2caa696 PM	174	int err;
96518518	175
d2caa696 PM	176	priv->key = ntohl(nla_get_be32(tb[NFTA_META_KEY]));
d2caa696 PM	177	switch (priv->key) {
96518518 PM	178	case NFT_META_LEN:
96518518 PM	179	case NFT_META_PROTOCOL:
124edfa9	180	case NFT_META_NFPROTO:
4566bf27	181	case NFT_META_L4PROTO:
96518518 PM	182	case NFT_META_PRIORITY:
	183	case NFT_META_MARK:
	184	case NFT_META_IIF:
	185	case NFT_META_OIF:
	186	case NFT_META_IIFNAME:
	187	case NFT_META_OIFNAME:
	188	case NFT_META_IIFTYPE:
	189	case NFT_META_OIFTYPE:
	190	case NFT_META_SKUID:
	191	case NFT_META_SKGID:
06efbd6d	192	#ifdef CONFIG_IP_ROUTE_CLASSID
96518518 PM	193	case NFT_META_RTCLASSID:
	194	#endif
	195	#ifdef CONFIG_NETWORK_SECMARK
	196	case NFT_META_SECMARK:
	197	#endif
d2caa696	198	break;
96518518 PM	199	default:
	200	return -EOPNOTSUPP;
	201	}
	202
d2caa696 PM	203	priv->dreg = ntohl(nla_get_be32(tb[NFTA_META_DREG]));
	204	err = nft_validate_output_register(priv->dreg);
	205	if (err < 0)
	206	return err;
	207
	208	err = nft_validate_data_load(ctx, priv->dreg, NULL, NFT_DATA_VALUE);
	209	if (err < 0)
	210	return err;
	211
	212	return 0;
e035b77a	213	}
aa45660c	214	EXPORT_SYMBOL_GPL(nft_meta_get_init);
e035b77a	215
aa45660c TB	216	int nft_meta_set_init(const struct nft_ctx *ctx,
	217	const struct nft_expr *expr,
	218	const struct nlattr * const tb[])
e035b77a ABG	219	{
	220	struct nft_meta *priv = nft_expr_priv(expr);
	221	int err;
	222
	223	priv->key = ntohl(nla_get_be32(tb[NFTA_META_KEY]));
d2caa696 PM	224	switch (priv->key) {
	225	case NFT_META_MARK:
	226	case NFT_META_PRIORITY:
	227	case NFT_META_NFTRACE:
	228	break;
	229	default:
	230	return -EOPNOTSUPP;
e035b77a ABG	231	}
e035b77a ABG	232
e035b77a	233	priv->sreg = ntohl(nla_get_be32(tb[NFTA_META_SREG]));
b38895c5 PNA	234	err = nft_validate_input_register(priv->sreg);
	235	if (err < 0)
	236	return err;
e035b77a ABG	237
e035b77a ABG	238	return 0;
96518518	239	}
aa45660c	240	EXPORT_SYMBOL_GPL(nft_meta_set_init);
96518518	241
aa45660c TB	242	int nft_meta_get_dump(struct sk_buff *skb,
aa45660c TB	243	const struct nft_expr *expr)
96518518 PM	244	{
	245	const struct nft_meta *priv = nft_expr_priv(expr);
	246
e035b77a ABG	247	if (nla_put_be32(skb, NFTA_META_KEY, htonl(priv->key)))
e035b77a ABG	248	goto nla_put_failure;
96518518 PM	249	if (nla_put_be32(skb, NFTA_META_DREG, htonl(priv->dreg)))
96518518 PM	250	goto nla_put_failure;
e035b77a ABG	251	return 0;
	252
	253	nla_put_failure:
	254	return -1;
	255	}
aa45660c	256	EXPORT_SYMBOL_GPL(nft_meta_get_dump);
e035b77a	257
aa45660c TB	258	int nft_meta_set_dump(struct sk_buff *skb,
aa45660c TB	259	const struct nft_expr *expr)
e035b77a ABG	260	{
	261	const struct nft_meta *priv = nft_expr_priv(expr);
	262
96518518 PM	263	if (nla_put_be32(skb, NFTA_META_KEY, htonl(priv->key)))
96518518 PM	264	goto nla_put_failure;
e035b77a ABG	265	if (nla_put_be32(skb, NFTA_META_SREG, htonl(priv->sreg)))
	266	goto nla_put_failure;
	267
96518518 PM	268	return 0;
	269
	270	nla_put_failure:
	271	return -1;
	272	}
aa45660c	273	EXPORT_SYMBOL_GPL(nft_meta_set_dump);
96518518	274
ef1f7df9	275	static struct nft_expr_type nft_meta_type;
e035b77a	276	static const struct nft_expr_ops nft_meta_get_ops = {
ef1f7df9	277	.type = &nft_meta_type,
96518518	278	.size = NFT_EXPR_SIZE(sizeof(struct nft_meta)),
e035b77a	279	.eval = nft_meta_get_eval,
d2caa696	280	.init = nft_meta_get_init,
e035b77a	281	.dump = nft_meta_get_dump,
ef1f7df9 PM	282	};
ef1f7df9 PM	283
e035b77a ABG	284	static const struct nft_expr_ops nft_meta_set_ops = {
	285	.type = &nft_meta_type,
	286	.size = NFT_EXPR_SIZE(sizeof(struct nft_meta)),
	287	.eval = nft_meta_set_eval,
d2caa696	288	.init = nft_meta_set_init,
e035b77a ABG	289	.dump = nft_meta_set_dump,
	290	};
	291
	292	static const struct nft_expr_ops *
	293	nft_meta_select_ops(const struct nft_ctx *ctx,
	294	const struct nlattr * const tb[])
	295	{
	296	if (tb[NFTA_META_KEY] == NULL)
	297	return ERR_PTR(-EINVAL);
	298
	299	if (tb[NFTA_META_DREG] && tb[NFTA_META_SREG])
	300	return ERR_PTR(-EINVAL);
	301
	302	if (tb[NFTA_META_DREG])
	303	return &nft_meta_get_ops;
	304
	305	if (tb[NFTA_META_SREG])
	306	return &nft_meta_set_ops;
	307
	308	return ERR_PTR(-EINVAL);
	309	}
	310
ef1f7df9 PM	311	static struct nft_expr_type nft_meta_type __read_mostly = {
ef1f7df9 PM	312	.name = "meta",
e035b77a	313	.select_ops = &nft_meta_select_ops,
96518518 PM	314	.policy = nft_meta_policy,
96518518 PM	315	.maxattr = NFTA_META_MAX,
ef1f7df9	316	.owner = THIS_MODULE,
96518518 PM	317	};
	318
	319	static int __init nft_meta_module_init(void)
	320	{
ef1f7df9	321	return nft_register_expr(&nft_meta_type);
96518518 PM	322	}
	323
	324	static void __exit nft_meta_module_exit(void)
	325	{
ef1f7df9	326	nft_unregister_expr(&nft_meta_type);
96518518 PM	327	}
	328
	329	module_init(nft_meta_module_init);
	330	module_exit(nft_meta_module_exit);
	331
	332	MODULE_LICENSE("GPL");
	333	MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>");
	334	MODULE_ALIAS_NFT_EXPR("meta");