![Pablo Neira Ayuso](/assets/img/avatar_default.png)
This code was based on the wrong asumption that you can probe based on the match/target private size that we get from userspace. This doesn't work at all when you have to dump the info back to userspace since you don't know what word size the userspace utility is using. Currently, the extensions that require arch compat are limit match and the ebt_mark match/target. The standard targets are not used by the nft-xt compat layer, so they are not affected. We can work around this limitation with a new revision that uses arch agnostic types. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
708 lines
18 KiB
C
708 lines
18 KiB
C
/*
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* (C) 2012-2013 by Pablo Neira Ayuso <pablo@netfilter.org>
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License version 2 as
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* published by the Free Software Foundation.
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*
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* This software has been sponsored by Sophos Astaro <http://www.sophos.com>
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*/
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#include <linux/kernel.h>
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#include <linux/init.h>
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#include <linux/module.h>
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#include <linux/netlink.h>
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#include <linux/netfilter.h>
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#include <linux/netfilter/nfnetlink.h>
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#include <linux/netfilter/nf_tables.h>
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#include <linux/netfilter/nf_tables_compat.h>
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#include <linux/netfilter/x_tables.h>
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#include <linux/netfilter_ipv4/ip_tables.h>
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#include <linux/netfilter_ipv6/ip6_tables.h>
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#include <asm/uaccess.h> /* for set_fs */
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#include <net/netfilter/nf_tables.h>
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union nft_entry {
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struct ipt_entry e4;
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struct ip6t_entry e6;
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};
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static inline void
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nft_compat_set_par(struct xt_action_param *par, void *xt, const void *xt_info)
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{
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par->target = xt;
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par->targinfo = xt_info;
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par->hotdrop = false;
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}
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static void nft_target_eval(const struct nft_expr *expr,
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struct nft_data data[NFT_REG_MAX + 1],
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const struct nft_pktinfo *pkt)
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{
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void *info = nft_expr_priv(expr);
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struct xt_target *target = expr->ops->data;
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struct sk_buff *skb = pkt->skb;
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int ret;
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nft_compat_set_par((struct xt_action_param *)&pkt->xt, target, info);
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ret = target->target(skb, &pkt->xt);
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if (pkt->xt.hotdrop)
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ret = NF_DROP;
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switch(ret) {
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case XT_CONTINUE:
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data[NFT_REG_VERDICT].verdict = NFT_CONTINUE;
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break;
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default:
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data[NFT_REG_VERDICT].verdict = ret;
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break;
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}
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return;
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}
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static const struct nla_policy nft_target_policy[NFTA_TARGET_MAX + 1] = {
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[NFTA_TARGET_NAME] = { .type = NLA_NUL_STRING },
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[NFTA_TARGET_REV] = { .type = NLA_U32 },
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[NFTA_TARGET_INFO] = { .type = NLA_BINARY },
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};
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static void
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nft_target_set_tgchk_param(struct xt_tgchk_param *par,
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const struct nft_ctx *ctx,
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struct xt_target *target, void *info,
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union nft_entry *entry, u8 proto, bool inv)
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{
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par->net = &init_net;
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par->table = ctx->table->name;
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switch (ctx->afi->family) {
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case AF_INET:
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entry->e4.ip.proto = proto;
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entry->e4.ip.invflags = inv ? IPT_INV_PROTO : 0;
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break;
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case AF_INET6:
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entry->e6.ipv6.proto = proto;
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entry->e6.ipv6.invflags = inv ? IP6T_INV_PROTO : 0;
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break;
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}
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par->entryinfo = entry;
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par->target = target;
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par->targinfo = info;
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if (ctx->chain->flags & NFT_BASE_CHAIN) {
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const struct nft_base_chain *basechain =
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nft_base_chain(ctx->chain);
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const struct nf_hook_ops *ops = &basechain->ops[0];
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par->hook_mask = 1 << ops->hooknum;
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}
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par->family = ctx->afi->family;
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}
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static void target_compat_from_user(struct xt_target *t, void *in, void *out)
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{
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int pad;
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memcpy(out, in, t->targetsize);
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pad = XT_ALIGN(t->targetsize) - t->targetsize;
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if (pad > 0)
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memset(out + t->targetsize, 0, pad);
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}
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static const struct nla_policy nft_rule_compat_policy[NFTA_RULE_COMPAT_MAX + 1] = {
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[NFTA_RULE_COMPAT_PROTO] = { .type = NLA_U32 },
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[NFTA_RULE_COMPAT_FLAGS] = { .type = NLA_U32 },
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};
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static int nft_parse_compat(const struct nlattr *attr, u8 *proto, bool *inv)
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{
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struct nlattr *tb[NFTA_RULE_COMPAT_MAX+1];
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u32 flags;
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int err;
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err = nla_parse_nested(tb, NFTA_RULE_COMPAT_MAX, attr,
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nft_rule_compat_policy);
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if (err < 0)
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return err;
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if (!tb[NFTA_RULE_COMPAT_PROTO] || !tb[NFTA_RULE_COMPAT_FLAGS])
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return -EINVAL;
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flags = ntohl(nla_get_be32(tb[NFTA_RULE_COMPAT_FLAGS]));
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if (flags & ~NFT_RULE_COMPAT_F_MASK)
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return -EINVAL;
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if (flags & NFT_RULE_COMPAT_F_INV)
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*inv = true;
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*proto = ntohl(nla_get_be32(tb[NFTA_RULE_COMPAT_PROTO]));
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return 0;
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}
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static int
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nft_target_init(const struct nft_ctx *ctx, const struct nft_expr *expr,
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const struct nlattr * const tb[])
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{
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void *info = nft_expr_priv(expr);
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struct xt_target *target = expr->ops->data;
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struct xt_tgchk_param par;
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size_t size = XT_ALIGN(nla_len(tb[NFTA_TARGET_INFO]));
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u8 proto = 0;
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bool inv = false;
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union nft_entry e = {};
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int ret;
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target_compat_from_user(target, nla_data(tb[NFTA_TARGET_INFO]), info);
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if (ctx->nla[NFTA_RULE_COMPAT]) {
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ret = nft_parse_compat(ctx->nla[NFTA_RULE_COMPAT], &proto, &inv);
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if (ret < 0)
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goto err;
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}
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nft_target_set_tgchk_param(&par, ctx, target, info, &e, proto, inv);
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ret = xt_check_target(&par, size, proto, inv);
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if (ret < 0)
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goto err;
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/* The standard target cannot be used */
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if (target->target == NULL) {
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ret = -EINVAL;
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goto err;
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}
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return 0;
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err:
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module_put(target->me);
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return ret;
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}
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static void
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nft_target_destroy(const struct nft_ctx *ctx, const struct nft_expr *expr)
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{
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struct xt_target *target = expr->ops->data;
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void *info = nft_expr_priv(expr);
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struct xt_tgdtor_param par;
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par.net = ctx->net;
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par.target = target;
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par.targinfo = info;
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par.family = ctx->afi->family;
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if (par.target->destroy != NULL)
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par.target->destroy(&par);
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module_put(target->me);
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}
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static int nft_target_dump(struct sk_buff *skb, const struct nft_expr *expr)
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{
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const struct xt_target *target = expr->ops->data;
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void *info = nft_expr_priv(expr);
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if (nla_put_string(skb, NFTA_TARGET_NAME, target->name) ||
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nla_put_be32(skb, NFTA_TARGET_REV, htonl(target->revision)) ||
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nla_put(skb, NFTA_TARGET_INFO, XT_ALIGN(target->targetsize), info))
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goto nla_put_failure;
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return 0;
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nla_put_failure:
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return -1;
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}
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static int nft_target_validate(const struct nft_ctx *ctx,
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const struct nft_expr *expr,
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const struct nft_data **data)
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{
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struct xt_target *target = expr->ops->data;
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unsigned int hook_mask = 0;
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if (ctx->chain->flags & NFT_BASE_CHAIN) {
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const struct nft_base_chain *basechain =
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nft_base_chain(ctx->chain);
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const struct nf_hook_ops *ops = &basechain->ops[0];
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hook_mask = 1 << ops->hooknum;
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if (hook_mask & target->hooks)
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return 0;
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/* This target is being called from an invalid chain */
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return -EINVAL;
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}
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return 0;
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}
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static void nft_match_eval(const struct nft_expr *expr,
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struct nft_data data[NFT_REG_MAX + 1],
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const struct nft_pktinfo *pkt)
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{
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void *info = nft_expr_priv(expr);
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struct xt_match *match = expr->ops->data;
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struct sk_buff *skb = pkt->skb;
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bool ret;
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nft_compat_set_par((struct xt_action_param *)&pkt->xt, match, info);
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ret = match->match(skb, (struct xt_action_param *)&pkt->xt);
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if (pkt->xt.hotdrop) {
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data[NFT_REG_VERDICT].verdict = NF_DROP;
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return;
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}
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switch(ret) {
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case true:
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data[NFT_REG_VERDICT].verdict = NFT_CONTINUE;
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break;
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case false:
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data[NFT_REG_VERDICT].verdict = NFT_BREAK;
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break;
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}
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}
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static const struct nla_policy nft_match_policy[NFTA_MATCH_MAX + 1] = {
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[NFTA_MATCH_NAME] = { .type = NLA_NUL_STRING },
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[NFTA_MATCH_REV] = { .type = NLA_U32 },
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[NFTA_MATCH_INFO] = { .type = NLA_BINARY },
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};
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/* struct xt_mtchk_param and xt_tgchk_param look very similar */
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static void
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nft_match_set_mtchk_param(struct xt_mtchk_param *par, const struct nft_ctx *ctx,
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struct xt_match *match, void *info,
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union nft_entry *entry, u8 proto, bool inv)
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{
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par->net = &init_net;
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par->table = ctx->table->name;
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switch (ctx->afi->family) {
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case AF_INET:
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entry->e4.ip.proto = proto;
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entry->e4.ip.invflags = inv ? IPT_INV_PROTO : 0;
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break;
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case AF_INET6:
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entry->e6.ipv6.proto = proto;
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entry->e6.ipv6.invflags = inv ? IP6T_INV_PROTO : 0;
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break;
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}
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par->entryinfo = entry;
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par->match = match;
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par->matchinfo = info;
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if (ctx->chain->flags & NFT_BASE_CHAIN) {
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const struct nft_base_chain *basechain =
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nft_base_chain(ctx->chain);
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const struct nf_hook_ops *ops = &basechain->ops[0];
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par->hook_mask = 1 << ops->hooknum;
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}
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par->family = ctx->afi->family;
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}
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static void match_compat_from_user(struct xt_match *m, void *in, void *out)
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{
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int pad;
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memcpy(out, in, m->matchsize);
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pad = XT_ALIGN(m->matchsize) - m->matchsize;
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if (pad > 0)
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memset(out + m->matchsize, 0, pad);
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}
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static int
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nft_match_init(const struct nft_ctx *ctx, const struct nft_expr *expr,
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const struct nlattr * const tb[])
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{
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void *info = nft_expr_priv(expr);
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struct xt_match *match = expr->ops->data;
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struct xt_mtchk_param par;
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size_t size = XT_ALIGN(nla_len(tb[NFTA_MATCH_INFO]));
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u8 proto = 0;
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bool inv = false;
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union nft_entry e = {};
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int ret;
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match_compat_from_user(match, nla_data(tb[NFTA_MATCH_INFO]), info);
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if (ctx->nla[NFTA_RULE_COMPAT]) {
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ret = nft_parse_compat(ctx->nla[NFTA_RULE_COMPAT], &proto, &inv);
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if (ret < 0)
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goto err;
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}
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nft_match_set_mtchk_param(&par, ctx, match, info, &e, proto, inv);
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ret = xt_check_match(&par, size, proto, inv);
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if (ret < 0)
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goto err;
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return 0;
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err:
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module_put(match->me);
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return ret;
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}
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static void
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nft_match_destroy(const struct nft_ctx *ctx, const struct nft_expr *expr)
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{
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struct xt_match *match = expr->ops->data;
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void *info = nft_expr_priv(expr);
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struct xt_mtdtor_param par;
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par.net = ctx->net;
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par.match = match;
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par.matchinfo = info;
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par.family = ctx->afi->family;
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if (par.match->destroy != NULL)
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par.match->destroy(&par);
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module_put(match->me);
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}
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static int nft_match_dump(struct sk_buff *skb, const struct nft_expr *expr)
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{
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void *info = nft_expr_priv(expr);
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struct xt_match *match = expr->ops->data;
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if (nla_put_string(skb, NFTA_MATCH_NAME, match->name) ||
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nla_put_be32(skb, NFTA_MATCH_REV, htonl(match->revision)) ||
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nla_put(skb, NFTA_MATCH_INFO, XT_ALIGN(match->matchsize), info))
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goto nla_put_failure;
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return 0;
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nla_put_failure:
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return -1;
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}
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static int nft_match_validate(const struct nft_ctx *ctx,
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const struct nft_expr *expr,
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const struct nft_data **data)
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{
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struct xt_match *match = expr->ops->data;
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unsigned int hook_mask = 0;
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if (ctx->chain->flags & NFT_BASE_CHAIN) {
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const struct nft_base_chain *basechain =
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nft_base_chain(ctx->chain);
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const struct nf_hook_ops *ops = &basechain->ops[0];
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hook_mask = 1 << ops->hooknum;
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if (hook_mask & match->hooks)
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return 0;
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/* This match is being called from an invalid chain */
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return -EINVAL;
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}
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return 0;
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}
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static int
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nfnl_compat_fill_info(struct sk_buff *skb, u32 portid, u32 seq, u32 type,
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int event, u16 family, const char *name,
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int rev, int target)
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{
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struct nlmsghdr *nlh;
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struct nfgenmsg *nfmsg;
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unsigned int flags = portid ? NLM_F_MULTI : 0;
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event |= NFNL_SUBSYS_NFT_COMPAT << 8;
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nlh = nlmsg_put(skb, portid, seq, event, sizeof(*nfmsg), flags);
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if (nlh == NULL)
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goto nlmsg_failure;
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nfmsg = nlmsg_data(nlh);
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nfmsg->nfgen_family = family;
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nfmsg->version = NFNETLINK_V0;
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nfmsg->res_id = 0;
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if (nla_put_string(skb, NFTA_COMPAT_NAME, name) ||
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nla_put_be32(skb, NFTA_COMPAT_REV, htonl(rev)) ||
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nla_put_be32(skb, NFTA_COMPAT_TYPE, htonl(target)))
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goto nla_put_failure;
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nlmsg_end(skb, nlh);
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return skb->len;
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nlmsg_failure:
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nla_put_failure:
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nlmsg_cancel(skb, nlh);
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return -1;
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}
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static int
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nfnl_compat_get(struct sock *nfnl, struct sk_buff *skb,
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const struct nlmsghdr *nlh, const struct nlattr * const tb[])
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{
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int ret = 0, target;
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struct nfgenmsg *nfmsg;
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const char *fmt;
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const char *name;
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u32 rev;
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struct sk_buff *skb2;
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if (tb[NFTA_COMPAT_NAME] == NULL ||
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tb[NFTA_COMPAT_REV] == NULL ||
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tb[NFTA_COMPAT_TYPE] == NULL)
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return -EINVAL;
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name = nla_data(tb[NFTA_COMPAT_NAME]);
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rev = ntohl(nla_get_be32(tb[NFTA_COMPAT_REV]));
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target = ntohl(nla_get_be32(tb[NFTA_COMPAT_TYPE]));
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nfmsg = nlmsg_data(nlh);
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switch(nfmsg->nfgen_family) {
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case AF_INET:
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fmt = "ipt_%s";
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break;
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case AF_INET6:
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fmt = "ip6t_%s";
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break;
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default:
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pr_err("nft_compat: unsupported protocol %d\n",
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nfmsg->nfgen_family);
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return -EINVAL;
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}
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try_then_request_module(xt_find_revision(nfmsg->nfgen_family, name,
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rev, target, &ret),
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fmt, name);
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if (ret < 0)
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return ret;
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skb2 = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
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if (skb2 == NULL)
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return -ENOMEM;
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/* include the best revision for this extension in the message */
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if (nfnl_compat_fill_info(skb2, NETLINK_CB(skb).portid,
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nlh->nlmsg_seq,
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NFNL_MSG_TYPE(nlh->nlmsg_type),
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NFNL_MSG_COMPAT_GET,
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nfmsg->nfgen_family,
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name, ret, target) <= 0) {
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kfree_skb(skb2);
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return -ENOSPC;
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}
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ret = netlink_unicast(nfnl, skb2, NETLINK_CB(skb).portid,
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|
MSG_DONTWAIT);
|
|
if (ret > 0)
|
|
ret = 0;
|
|
|
|
return ret == -EAGAIN ? -ENOBUFS : ret;
|
|
}
|
|
|
|
static const struct nla_policy nfnl_compat_policy_get[NFTA_COMPAT_MAX+1] = {
|
|
[NFTA_COMPAT_NAME] = { .type = NLA_NUL_STRING,
|
|
.len = NFT_COMPAT_NAME_MAX-1 },
|
|
[NFTA_COMPAT_REV] = { .type = NLA_U32 },
|
|
[NFTA_COMPAT_TYPE] = { .type = NLA_U32 },
|
|
};
|
|
|
|
static const struct nfnl_callback nfnl_nft_compat_cb[NFNL_MSG_COMPAT_MAX] = {
|
|
[NFNL_MSG_COMPAT_GET] = { .call = nfnl_compat_get,
|
|
.attr_count = NFTA_COMPAT_MAX,
|
|
.policy = nfnl_compat_policy_get },
|
|
};
|
|
|
|
static const struct nfnetlink_subsystem nfnl_compat_subsys = {
|
|
.name = "nft-compat",
|
|
.subsys_id = NFNL_SUBSYS_NFT_COMPAT,
|
|
.cb_count = NFNL_MSG_COMPAT_MAX,
|
|
.cb = nfnl_nft_compat_cb,
|
|
};
|
|
|
|
static LIST_HEAD(nft_match_list);
|
|
|
|
struct nft_xt {
|
|
struct list_head head;
|
|
struct nft_expr_ops ops;
|
|
};
|
|
|
|
static struct nft_expr_type nft_match_type;
|
|
|
|
static const struct nft_expr_ops *
|
|
nft_match_select_ops(const struct nft_ctx *ctx,
|
|
const struct nlattr * const tb[])
|
|
{
|
|
struct nft_xt *nft_match;
|
|
struct xt_match *match;
|
|
char *mt_name;
|
|
__u32 rev, family;
|
|
|
|
if (tb[NFTA_MATCH_NAME] == NULL ||
|
|
tb[NFTA_MATCH_REV] == NULL ||
|
|
tb[NFTA_MATCH_INFO] == NULL)
|
|
return ERR_PTR(-EINVAL);
|
|
|
|
mt_name = nla_data(tb[NFTA_MATCH_NAME]);
|
|
rev = ntohl(nla_get_be32(tb[NFTA_MATCH_REV]));
|
|
family = ctx->afi->family;
|
|
|
|
/* Re-use the existing match if it's already loaded. */
|
|
list_for_each_entry(nft_match, &nft_match_list, head) {
|
|
struct xt_match *match = nft_match->ops.data;
|
|
|
|
if (strcmp(match->name, mt_name) == 0 &&
|
|
match->revision == rev && match->family == family)
|
|
return &nft_match->ops;
|
|
}
|
|
|
|
match = xt_request_find_match(family, mt_name, rev);
|
|
if (IS_ERR(match))
|
|
return ERR_PTR(-ENOENT);
|
|
|
|
/* This is the first time we use this match, allocate operations */
|
|
nft_match = kzalloc(sizeof(struct nft_xt), GFP_KERNEL);
|
|
if (nft_match == NULL)
|
|
return ERR_PTR(-ENOMEM);
|
|
|
|
nft_match->ops.type = &nft_match_type;
|
|
nft_match->ops.size = NFT_EXPR_SIZE(XT_ALIGN(match->matchsize));
|
|
nft_match->ops.eval = nft_match_eval;
|
|
nft_match->ops.init = nft_match_init;
|
|
nft_match->ops.destroy = nft_match_destroy;
|
|
nft_match->ops.dump = nft_match_dump;
|
|
nft_match->ops.validate = nft_match_validate;
|
|
nft_match->ops.data = match;
|
|
|
|
list_add(&nft_match->head, &nft_match_list);
|
|
|
|
return &nft_match->ops;
|
|
}
|
|
|
|
static void nft_match_release(void)
|
|
{
|
|
struct nft_xt *nft_match, *tmp;
|
|
|
|
list_for_each_entry_safe(nft_match, tmp, &nft_match_list, head)
|
|
kfree(nft_match);
|
|
}
|
|
|
|
static struct nft_expr_type nft_match_type __read_mostly = {
|
|
.name = "match",
|
|
.select_ops = nft_match_select_ops,
|
|
.policy = nft_match_policy,
|
|
.maxattr = NFTA_MATCH_MAX,
|
|
.owner = THIS_MODULE,
|
|
};
|
|
|
|
static LIST_HEAD(nft_target_list);
|
|
|
|
static struct nft_expr_type nft_target_type;
|
|
|
|
static const struct nft_expr_ops *
|
|
nft_target_select_ops(const struct nft_ctx *ctx,
|
|
const struct nlattr * const tb[])
|
|
{
|
|
struct nft_xt *nft_target;
|
|
struct xt_target *target;
|
|
char *tg_name;
|
|
__u32 rev, family;
|
|
|
|
if (tb[NFTA_TARGET_NAME] == NULL ||
|
|
tb[NFTA_TARGET_REV] == NULL ||
|
|
tb[NFTA_TARGET_INFO] == NULL)
|
|
return ERR_PTR(-EINVAL);
|
|
|
|
tg_name = nla_data(tb[NFTA_TARGET_NAME]);
|
|
rev = ntohl(nla_get_be32(tb[NFTA_TARGET_REV]));
|
|
family = ctx->afi->family;
|
|
|
|
/* Re-use the existing target if it's already loaded. */
|
|
list_for_each_entry(nft_target, &nft_match_list, head) {
|
|
struct xt_target *target = nft_target->ops.data;
|
|
|
|
if (strcmp(target->name, tg_name) == 0 &&
|
|
target->revision == rev && target->family == family)
|
|
return &nft_target->ops;
|
|
}
|
|
|
|
target = xt_request_find_target(family, tg_name, rev);
|
|
if (IS_ERR(target))
|
|
return ERR_PTR(-ENOENT);
|
|
|
|
/* This is the first time we use this target, allocate operations */
|
|
nft_target = kzalloc(sizeof(struct nft_xt), GFP_KERNEL);
|
|
if (nft_target == NULL)
|
|
return ERR_PTR(-ENOMEM);
|
|
|
|
nft_target->ops.type = &nft_target_type;
|
|
nft_target->ops.size = NFT_EXPR_SIZE(XT_ALIGN(target->targetsize));
|
|
nft_target->ops.eval = nft_target_eval;
|
|
nft_target->ops.init = nft_target_init;
|
|
nft_target->ops.destroy = nft_target_destroy;
|
|
nft_target->ops.dump = nft_target_dump;
|
|
nft_target->ops.validate = nft_target_validate;
|
|
nft_target->ops.data = target;
|
|
|
|
list_add(&nft_target->head, &nft_target_list);
|
|
|
|
return &nft_target->ops;
|
|
}
|
|
|
|
static void nft_target_release(void)
|
|
{
|
|
struct nft_xt *nft_target, *tmp;
|
|
|
|
list_for_each_entry_safe(nft_target, tmp, &nft_target_list, head)
|
|
kfree(nft_target);
|
|
}
|
|
|
|
static struct nft_expr_type nft_target_type __read_mostly = {
|
|
.name = "target",
|
|
.select_ops = nft_target_select_ops,
|
|
.policy = nft_target_policy,
|
|
.maxattr = NFTA_TARGET_MAX,
|
|
.owner = THIS_MODULE,
|
|
};
|
|
|
|
static int __init nft_compat_module_init(void)
|
|
{
|
|
int ret;
|
|
|
|
ret = nft_register_expr(&nft_match_type);
|
|
if (ret < 0)
|
|
return ret;
|
|
|
|
ret = nft_register_expr(&nft_target_type);
|
|
if (ret < 0)
|
|
goto err_match;
|
|
|
|
ret = nfnetlink_subsys_register(&nfnl_compat_subsys);
|
|
if (ret < 0) {
|
|
pr_err("nft_compat: cannot register with nfnetlink.\n");
|
|
goto err_target;
|
|
}
|
|
|
|
pr_info("nf_tables_compat: (c) 2012 Pablo Neira Ayuso <pablo@netfilter.org>\n");
|
|
|
|
return ret;
|
|
|
|
err_target:
|
|
nft_unregister_expr(&nft_target_type);
|
|
err_match:
|
|
nft_unregister_expr(&nft_match_type);
|
|
return ret;
|
|
}
|
|
|
|
static void __exit nft_compat_module_exit(void)
|
|
{
|
|
nfnetlink_subsys_unregister(&nfnl_compat_subsys);
|
|
nft_unregister_expr(&nft_target_type);
|
|
nft_unregister_expr(&nft_match_type);
|
|
nft_match_release();
|
|
nft_target_release();
|
|
}
|
|
|
|
MODULE_ALIAS_NFNL_SUBSYS(NFNL_SUBSYS_NFT_COMPAT);
|
|
|
|
module_init(nft_compat_module_init);
|
|
module_exit(nft_compat_module_exit);
|
|
|
|
MODULE_LICENSE("GPL");
|
|
MODULE_AUTHOR("Pablo Neira Ayuso <pablo@netfilter.org>");
|
|
MODULE_ALIAS_NFT_EXPR("match");
|
|
MODULE_ALIAS_NFT_EXPR("target");
|