diff options
Diffstat (limited to 'net/netfilter/nft_reject.c')
| -rw-r--r-- | net/netfilter/nft_reject.c | 145 |
1 files changed, 145 insertions, 0 deletions
diff --git a/net/netfilter/nft_reject.c b/net/netfilter/nft_reject.c new file mode 100644 index 000000000000..5e204711d704 --- /dev/null +++ b/net/netfilter/nft_reject.c @@ -0,0 +1,145 @@ +/* + * Copyright (c) 2008-2009 Patrick McHardy <kaber@trash.net> + * Copyright (c) 2013 Eric Leblond <eric@regit.org> + * + * 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/netfilter/nf_tables.h> +#include <net/icmp.h> +#include <net/netfilter/ipv4/nf_reject.h> + +#if IS_ENABLED(CONFIG_NF_TABLES_IPV6) +#include <net/netfilter/ipv6/nf_reject.h> +#endif + +struct nft_reject { + enum nft_reject_types type:8; + u8 icmp_code; + u8 family; +}; + +static void nft_reject_eval(const struct nft_expr *expr, + struct nft_data data[NFT_REG_MAX + 1], + const struct nft_pktinfo *pkt) +{ + struct nft_reject *priv = nft_expr_priv(expr); +#if IS_ENABLED(CONFIG_NF_TABLES_IPV6) + struct net *net = dev_net((pkt->in != NULL) ? pkt->in : pkt->out); +#endif + switch (priv->type) { + case NFT_REJECT_ICMP_UNREACH: + if (priv->family == NFPROTO_IPV4) + nf_send_unreach(pkt->skb, priv->icmp_code); +#if IS_ENABLED(CONFIG_NF_TABLES_IPV6) + else if (priv->family == NFPROTO_IPV6) + nf_send_unreach6(net, pkt->skb, priv->icmp_code, + pkt->ops->hooknum); +#endif + break; + case NFT_REJECT_TCP_RST: + if (priv->family == NFPROTO_IPV4) + nf_send_reset(pkt->skb, pkt->ops->hooknum); +#if IS_ENABLED(CONFIG_NF_TABLES_IPV6) + else if (priv->family == NFPROTO_IPV6) + nf_send_reset6(net, pkt->skb, pkt->ops->hooknum); +#endif + break; + } + + data[NFT_REG_VERDICT].verdict = NF_DROP; +} + +static const struct nla_policy nft_reject_policy[NFTA_REJECT_MAX + 1] = { + [NFTA_REJECT_TYPE] = { .type = NLA_U32 }, + [NFTA_REJECT_ICMP_CODE] = { .type = NLA_U8 }, +}; + +static int nft_reject_init(const struct nft_ctx *ctx, + const struct nft_expr *expr, + const struct nlattr * const tb[]) +{ + struct nft_reject *priv = nft_expr_priv(expr); + + if (tb[NFTA_REJECT_TYPE] == NULL) + return -EINVAL; + + priv->family = ctx->afi->family; + priv->type = ntohl(nla_get_be32(tb[NFTA_REJECT_TYPE])); + switch (priv->type) { + case NFT_REJECT_ICMP_UNREACH: + if (tb[NFTA_REJECT_ICMP_CODE] == NULL) + return -EINVAL; + priv->icmp_code = nla_get_u8(tb[NFTA_REJECT_ICMP_CODE]); + case NFT_REJECT_TCP_RST: + break; + default: + return -EINVAL; + } + + return 0; +} + +static int nft_reject_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: + if (nla_put_u8(skb, NFTA_REJECT_ICMP_CODE, priv->icmp_code)) + goto nla_put_failure; + break; + } + + return 0; + +nla_put_failure: + return -1; +} + +static struct nft_expr_type nft_reject_type; +static const struct nft_expr_ops nft_reject_ops = { + .type = &nft_reject_type, + .size = NFT_EXPR_SIZE(sizeof(struct nft_reject)), + .eval = nft_reject_eval, + .init = nft_reject_init, + .dump = nft_reject_dump, +}; + +static struct nft_expr_type nft_reject_type __read_mostly = { + .name = "reject", + .ops = &nft_reject_ops, + .policy = nft_reject_policy, + .maxattr = NFTA_REJECT_MAX, + .owner = THIS_MODULE, +}; + +static int __init nft_reject_module_init(void) +{ + return nft_register_expr(&nft_reject_type); +} + +static void __exit nft_reject_module_exit(void) +{ + nft_unregister_expr(&nft_reject_type); +} + +module_init(nft_reject_module_init); +module_exit(nft_reject_module_exit); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>"); +MODULE_ALIAS_NFT_EXPR("reject"); |