1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Copyright (c) 2015 Pablo Neira Ayuso <pablo@netfilter.org> 4 */ 5 6 #include <linux/kernel.h> 7 #include <linux/init.h> 8 #include <linux/module.h> 9 #include <linux/netlink.h> 10 #include <linux/netfilter.h> 11 #include <linux/netfilter/nf_tables.h> 12 #include <net/netfilter/nf_tables.h> 13 #include <net/netfilter/ipv6/nf_dup_ipv6.h> 14 15 struct nft_dup_ipv6 { 16 enum nft_registers sreg_addr:8; 17 enum nft_registers sreg_dev:8; 18 }; 19 20 static void nft_dup_ipv6_eval(const struct nft_expr *expr, 21 struct nft_regs *regs, 22 const struct nft_pktinfo *pkt) 23 { 24 struct nft_dup_ipv6 *priv = nft_expr_priv(expr); 25 struct in6_addr *gw = (struct in6_addr *)®s->data[priv->sreg_addr]; 26 int oif = priv->sreg_dev ? regs->data[priv->sreg_dev] : -1; 27 28 nf_dup_ipv6(nft_net(pkt), pkt->skb, nft_hook(pkt), gw, oif); 29 } 30 31 static int nft_dup_ipv6_init(const struct nft_ctx *ctx, 32 const struct nft_expr *expr, 33 const struct nlattr * const tb[]) 34 { 35 struct nft_dup_ipv6 *priv = nft_expr_priv(expr); 36 int err; 37 38 if (tb[NFTA_DUP_SREG_ADDR] == NULL) 39 return -EINVAL; 40 41 priv->sreg_addr = nft_parse_register(tb[NFTA_DUP_SREG_ADDR]); 42 err = nft_validate_register_load(priv->sreg_addr, sizeof(struct in6_addr)); 43 if (err < 0) 44 return err; 45 46 if (tb[NFTA_DUP_SREG_DEV] != NULL) { 47 priv->sreg_dev = nft_parse_register(tb[NFTA_DUP_SREG_DEV]); 48 return nft_validate_register_load(priv->sreg_dev, sizeof(int)); 49 } 50 return 0; 51 } 52 53 static int nft_dup_ipv6_dump(struct sk_buff *skb, const struct nft_expr *expr) 54 { 55 struct nft_dup_ipv6 *priv = nft_expr_priv(expr); 56 57 if (nft_dump_register(skb, NFTA_DUP_SREG_ADDR, priv->sreg_addr)) 58 goto nla_put_failure; 59 if (priv->sreg_dev && 60 nft_dump_register(skb, NFTA_DUP_SREG_DEV, priv->sreg_dev)) 61 goto nla_put_failure; 62 63 return 0; 64 65 nla_put_failure: 66 return -1; 67 } 68 69 static struct nft_expr_type nft_dup_ipv6_type; 70 static const struct nft_expr_ops nft_dup_ipv6_ops = { 71 .type = &nft_dup_ipv6_type, 72 .size = NFT_EXPR_SIZE(sizeof(struct nft_dup_ipv6)), 73 .eval = nft_dup_ipv6_eval, 74 .init = nft_dup_ipv6_init, 75 .dump = nft_dup_ipv6_dump, 76 }; 77 78 static const struct nla_policy nft_dup_ipv6_policy[NFTA_DUP_MAX + 1] = { 79 [NFTA_DUP_SREG_ADDR] = { .type = NLA_U32 }, 80 [NFTA_DUP_SREG_DEV] = { .type = NLA_U32 }, 81 }; 82 83 static struct nft_expr_type nft_dup_ipv6_type __read_mostly = { 84 .family = NFPROTO_IPV6, 85 .name = "dup", 86 .ops = &nft_dup_ipv6_ops, 87 .policy = nft_dup_ipv6_policy, 88 .maxattr = NFTA_DUP_MAX, 89 .owner = THIS_MODULE, 90 }; 91 92 static int __init nft_dup_ipv6_module_init(void) 93 { 94 return nft_register_expr(&nft_dup_ipv6_type); 95 } 96 97 static void __exit nft_dup_ipv6_module_exit(void) 98 { 99 nft_unregister_expr(&nft_dup_ipv6_type); 100 } 101 102 module_init(nft_dup_ipv6_module_init); 103 module_exit(nft_dup_ipv6_module_exit); 104 105 MODULE_LICENSE("GPL"); 106 MODULE_AUTHOR("Pablo Neira Ayuso <pablo@netfilter.org>"); 107 MODULE_ALIAS_NFT_AF_EXPR(AF_INET6, "dup"); 108 MODULE_DESCRIPTION("IPv6 nftables packet duplication support"); 109