| /* |
| * Copyright (c) 2014 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. |
| */ |
| |
| #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_reject.h> |
| #include <net/netfilter/ipv4/nf_reject.h> |
| #include <net/netfilter/ipv6/nf_reject.h> |
| |
| static void nft_reject_inet_eval(const struct nft_expr *expr, |
| struct nft_regs *regs, |
| const struct nft_pktinfo *pkt) |
| { |
| struct nft_reject *priv = nft_expr_priv(expr); |
| |
| switch (pkt->pf) { |
| case NFPROTO_IPV4: |
| switch (priv->type) { |
| case NFT_REJECT_ICMP_UNREACH: |
| nf_send_unreach(pkt->skb, priv->icmp_code, |
| pkt->hook); |
| break; |
| case NFT_REJECT_TCP_RST: |
| nf_send_reset(pkt->net, pkt->skb, pkt->hook); |
| break; |
| case NFT_REJECT_ICMPX_UNREACH: |
| nf_send_unreach(pkt->skb, |
| nft_reject_icmp_code(priv->icmp_code), |
| pkt->hook); |
| break; |
| } |
| break; |
| case NFPROTO_IPV6: |
| switch (priv->type) { |
| case NFT_REJECT_ICMP_UNREACH: |
| nf_send_unreach6(pkt->net, pkt->skb, priv->icmp_code, |
| pkt->hook); |
| break; |
| case NFT_REJECT_TCP_RST: |
| nf_send_reset6(pkt->net, pkt->skb, pkt->hook); |
| break; |
| case NFT_REJECT_ICMPX_UNREACH: |
| nf_send_unreach6(pkt->net, pkt->skb, |
| nft_reject_icmpv6_code(priv->icmp_code), |
| pkt->hook); |
| break; |
| } |
| break; |
| } |
| |
| regs->verdict.code = NF_DROP; |
| } |
| |
| static int nft_reject_inet_init(const struct nft_ctx *ctx, |
| const struct nft_expr *expr, |
| const struct nlattr * const tb[]) |
| { |
| struct nft_reject *priv = nft_expr_priv(expr); |
| int icmp_code; |
| |
| if (tb[NFTA_REJECT_TYPE] == NULL) |
| return -EINVAL; |
| |
| priv->type = ntohl(nla_get_be32(tb[NFTA_REJECT_TYPE])); |
| switch (priv->type) { |
| case NFT_REJECT_ICMP_UNREACH: |
| case NFT_REJECT_ICMPX_UNREACH: |
| if (tb[NFTA_REJECT_ICMP_CODE] == NULL) |
| return -EINVAL; |
| |
| icmp_code = nla_get_u8(tb[NFTA_REJECT_ICMP_CODE]); |
| if (priv->type == NFT_REJECT_ICMPX_UNREACH && |
| icmp_code > NFT_REJECT_ICMPX_MAX) |
| return -EINVAL; |
| |
| priv->icmp_code = icmp_code; |
| break; |
| case NFT_REJECT_TCP_RST: |
| break; |
| default: |
| return -EINVAL; |
| } |
| return 0; |
| } |
| |
| static int nft_reject_inet_dump(struct sk_buff *skb, |
| const struct nft_expr *expr) |
| { |
| const struct nft_reject *priv = nft_expr_priv(expr); |
| |
| if (nla_put_be32(skb, NFTA_REJECT_TYPE, htonl(priv->type))) |
| goto nla_put_failure; |
| |
| switch (priv->type) { |
| case NFT_REJECT_ICMP_UNREACH: |
| case NFT_REJECT_ICMPX_UNREACH: |
| if (nla_put_u8(skb, NFTA_REJECT_ICMP_CODE, priv->icmp_code)) |
| goto nla_put_failure; |
| break; |
| default: |
| break; |
| } |
| |
| return 0; |
| |
| nla_put_failure: |
| return -1; |
| } |
| |
| static struct nft_expr_type nft_reject_inet_type; |
| static const struct nft_expr_ops nft_reject_inet_ops = { |
| .type = &nft_reject_inet_type, |
| .size = NFT_EXPR_SIZE(sizeof(struct nft_reject)), |
| .eval = nft_reject_inet_eval, |
| .init = nft_reject_inet_init, |
| .dump = nft_reject_inet_dump, |
| }; |
| |
| static struct nft_expr_type nft_reject_inet_type __read_mostly = { |
| .family = NFPROTO_INET, |
| .name = "reject", |
| .ops = &nft_reject_inet_ops, |
| .policy = nft_reject_policy, |
| .maxattr = NFTA_REJECT_MAX, |
| .owner = THIS_MODULE, |
| }; |
| |
| static int __init nft_reject_inet_module_init(void) |
| { |
| return nft_register_expr(&nft_reject_inet_type); |
| } |
| |
| static void __exit nft_reject_inet_module_exit(void) |
| { |
| nft_unregister_expr(&nft_reject_inet_type); |
| } |
| |
| module_init(nft_reject_inet_module_init); |
| module_exit(nft_reject_inet_module_exit); |
| |
| MODULE_LICENSE("GPL"); |
| MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>"); |
| MODULE_ALIAS_NFT_AF_EXPR(1, "reject"); |