| // SPDX-License-Identifier: GPL-2.0 |
| #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/netfilter/nf_tables.h> |
| #include <net/netfilter/nft_meta.h> |
| #include <linux/if_bridge.h> |
| #include <uapi/linux/netfilter_bridge.h> /* NF_BR_PRE_ROUTING */ |
| |
| #include "../br_private.h" |
| |
| static const struct net_device * |
| nft_meta_get_bridge(const struct net_device *dev) |
| { |
| if (dev && netif_is_bridge_port(dev)) |
| return netdev_master_upper_dev_get_rcu((struct net_device *)dev); |
| |
| return NULL; |
| } |
| |
| static void nft_meta_bridge_get_eval(const struct nft_expr *expr, |
| struct nft_regs *regs, |
| const struct nft_pktinfo *pkt) |
| { |
| const struct nft_meta *priv = nft_expr_priv(expr); |
| const struct net_device *in = nft_in(pkt), *out = nft_out(pkt); |
| u32 *dest = ®s->data[priv->dreg]; |
| const struct net_device *br_dev; |
| |
| switch (priv->key) { |
| case NFT_META_BRI_IIFNAME: |
| br_dev = nft_meta_get_bridge(in); |
| break; |
| case NFT_META_BRI_OIFNAME: |
| br_dev = nft_meta_get_bridge(out); |
| break; |
| case NFT_META_BRI_IIFPVID: { |
| u16 p_pvid; |
| |
| br_dev = nft_meta_get_bridge(in); |
| if (!br_dev || !br_vlan_enabled(br_dev)) |
| goto err; |
| |
| br_vlan_get_pvid_rcu(in, &p_pvid); |
| nft_reg_store16(dest, p_pvid); |
| return; |
| } |
| case NFT_META_BRI_IIFVPROTO: { |
| u16 p_proto; |
| |
| br_dev = nft_meta_get_bridge(in); |
| if (!br_dev || !br_vlan_enabled(br_dev)) |
| goto err; |
| |
| br_vlan_get_proto(br_dev, &p_proto); |
| nft_reg_store_be16(dest, htons(p_proto)); |
| return; |
| } |
| default: |
| return nft_meta_get_eval(expr, regs, pkt); |
| } |
| |
| strncpy((char *)dest, br_dev ? br_dev->name : "", IFNAMSIZ); |
| return; |
| err: |
| regs->verdict.code = NFT_BREAK; |
| } |
| |
| static int nft_meta_bridge_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); |
| unsigned int len; |
| |
| priv->key = ntohl(nla_get_be32(tb[NFTA_META_KEY])); |
| switch (priv->key) { |
| case NFT_META_BRI_IIFNAME: |
| case NFT_META_BRI_OIFNAME: |
| len = IFNAMSIZ; |
| break; |
| case NFT_META_BRI_IIFPVID: |
| case NFT_META_BRI_IIFVPROTO: |
| len = sizeof(u16); |
| break; |
| default: |
| return nft_meta_get_init(ctx, expr, tb); |
| } |
| |
| priv->len = len; |
| return nft_parse_register_store(ctx, tb[NFTA_META_DREG], &priv->dreg, |
| NULL, NFT_DATA_VALUE, len); |
| } |
| |
| static struct nft_expr_type nft_meta_bridge_type; |
| static const struct nft_expr_ops nft_meta_bridge_get_ops = { |
| .type = &nft_meta_bridge_type, |
| .size = NFT_EXPR_SIZE(sizeof(struct nft_meta)), |
| .eval = nft_meta_bridge_get_eval, |
| .init = nft_meta_bridge_get_init, |
| .dump = nft_meta_get_dump, |
| .reduce = nft_meta_get_reduce, |
| }; |
| |
| static void nft_meta_bridge_set_eval(const struct nft_expr *expr, |
| struct nft_regs *regs, |
| const struct nft_pktinfo *pkt) |
| { |
| const struct nft_meta *meta = nft_expr_priv(expr); |
| u32 *sreg = ®s->data[meta->sreg]; |
| struct sk_buff *skb = pkt->skb; |
| u8 value8; |
| |
| switch (meta->key) { |
| case NFT_META_BRI_BROUTE: |
| value8 = nft_reg_load8(sreg); |
| BR_INPUT_SKB_CB(skb)->br_netfilter_broute = !!value8; |
| break; |
| default: |
| nft_meta_set_eval(expr, regs, pkt); |
| } |
| } |
| |
| static int nft_meta_bridge_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); |
| unsigned int len; |
| int err; |
| |
| priv->key = ntohl(nla_get_be32(tb[NFTA_META_KEY])); |
| switch (priv->key) { |
| case NFT_META_BRI_BROUTE: |
| len = sizeof(u8); |
| break; |
| default: |
| return nft_meta_set_init(ctx, expr, tb); |
| } |
| |
| priv->len = len; |
| err = nft_parse_register_load(tb[NFTA_META_SREG], &priv->sreg, len); |
| if (err < 0) |
| return err; |
| |
| return 0; |
| } |
| |
| static bool nft_meta_bridge_set_reduce(struct nft_regs_track *track, |
| const struct nft_expr *expr) |
| { |
| int i; |
| |
| for (i = 0; i < NFT_REG32_NUM; i++) { |
| if (!track->regs[i].selector) |
| continue; |
| |
| if (track->regs[i].selector->ops != &nft_meta_bridge_get_ops) |
| continue; |
| |
| __nft_reg_track_cancel(track, i); |
| } |
| |
| return false; |
| } |
| |
| static int nft_meta_bridge_set_validate(const struct nft_ctx *ctx, |
| const struct nft_expr *expr, |
| const struct nft_data **data) |
| { |
| struct nft_meta *priv = nft_expr_priv(expr); |
| unsigned int hooks; |
| |
| switch (priv->key) { |
| case NFT_META_BRI_BROUTE: |
| hooks = 1 << NF_BR_PRE_ROUTING; |
| break; |
| default: |
| return nft_meta_set_validate(ctx, expr, data); |
| } |
| |
| return nft_chain_validate_hooks(ctx->chain, hooks); |
| } |
| |
| static const struct nft_expr_ops nft_meta_bridge_set_ops = { |
| .type = &nft_meta_bridge_type, |
| .size = NFT_EXPR_SIZE(sizeof(struct nft_meta)), |
| .eval = nft_meta_bridge_set_eval, |
| .init = nft_meta_bridge_set_init, |
| .destroy = nft_meta_set_destroy, |
| .dump = nft_meta_set_dump, |
| .reduce = nft_meta_bridge_set_reduce, |
| .validate = nft_meta_bridge_set_validate, |
| }; |
| |
| static const struct nft_expr_ops * |
| nft_meta_bridge_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_bridge_get_ops; |
| |
| if (tb[NFTA_META_SREG]) |
| return &nft_meta_bridge_set_ops; |
| |
| return ERR_PTR(-EINVAL); |
| } |
| |
| static struct nft_expr_type nft_meta_bridge_type __read_mostly = { |
| .family = NFPROTO_BRIDGE, |
| .name = "meta", |
| .select_ops = nft_meta_bridge_select_ops, |
| .policy = nft_meta_policy, |
| .maxattr = NFTA_META_MAX, |
| .owner = THIS_MODULE, |
| }; |
| |
| static int __init nft_meta_bridge_module_init(void) |
| { |
| return nft_register_expr(&nft_meta_bridge_type); |
| } |
| |
| static void __exit nft_meta_bridge_module_exit(void) |
| { |
| nft_unregister_expr(&nft_meta_bridge_type); |
| } |
| |
| module_init(nft_meta_bridge_module_init); |
| module_exit(nft_meta_bridge_module_exit); |
| |
| MODULE_LICENSE("GPL"); |
| MODULE_AUTHOR("wenxu <wenxu@ucloud.cn>"); |
| MODULE_ALIAS_NFT_AF_EXPR(AF_BRIDGE, "meta"); |
| MODULE_DESCRIPTION("Support for bridge dedicated meta key"); |