diff options
Diffstat (limited to 'net/netfilter/nft_rt.c')
| -rw-r--r-- | net/netfilter/nft_rt.c | 153 |
1 files changed, 153 insertions, 0 deletions
diff --git a/net/netfilter/nft_rt.c b/net/netfilter/nft_rt.c new file mode 100644 index 000000000000..9e5ec1f67020 --- /dev/null +++ b/net/netfilter/nft_rt.c @@ -0,0 +1,153 @@ +/* + * Copyright (c) 2016 Anders K. Pedersen <akp@cohaesio.com> + * + * 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/dst.h> +#include <net/ip6_route.h> +#include <net/route.h> +#include <net/netfilter/nf_tables.h> +#include <net/netfilter/nf_tables_core.h> + +struct nft_rt { + enum nft_rt_keys key:8; + enum nft_registers dreg:8; +}; + +void nft_rt_get_eval(const struct nft_expr *expr, + struct nft_regs *regs, + const struct nft_pktinfo *pkt) +{ + const struct nft_rt *priv = nft_expr_priv(expr); + const struct sk_buff *skb = pkt->skb; + u32 *dest = ®s->data[priv->dreg]; + const struct dst_entry *dst; + + dst = skb_dst(skb); + if (!dst) + goto err; + + switch (priv->key) { +#ifdef CONFIG_IP_ROUTE_CLASSID + case NFT_RT_CLASSID: + *dest = dst->tclassid; + break; +#endif + case NFT_RT_NEXTHOP4: + if (pkt->pf != NFPROTO_IPV4) + goto err; + + *dest = rt_nexthop((const struct rtable *)dst, + ip_hdr(skb)->daddr); + break; + case NFT_RT_NEXTHOP6: + if (pkt->pf != NFPROTO_IPV6) + goto err; + + memcpy(dest, rt6_nexthop((struct rt6_info *)dst, + &ipv6_hdr(skb)->daddr), + sizeof(struct in6_addr)); + break; + default: + WARN_ON(1); + goto err; + } + return; + +err: + regs->verdict.code = NFT_BREAK; +} + +const struct nla_policy nft_rt_policy[NFTA_RT_MAX + 1] = { + [NFTA_RT_DREG] = { .type = NLA_U32 }, + [NFTA_RT_KEY] = { .type = NLA_U32 }, +}; + +int nft_rt_get_init(const struct nft_ctx *ctx, + const struct nft_expr *expr, + const struct nlattr * const tb[]) +{ + struct nft_rt *priv = nft_expr_priv(expr); + unsigned int len; + + if (tb[NFTA_RT_KEY] == NULL || + tb[NFTA_RT_DREG] == NULL) + return -EINVAL; + + priv->key = ntohl(nla_get_be32(tb[NFTA_RT_KEY])); + switch (priv->key) { +#ifdef CONFIG_IP_ROUTE_CLASSID + case NFT_RT_CLASSID: +#endif + case NFT_RT_NEXTHOP4: + len = sizeof(u32); + break; + case NFT_RT_NEXTHOP6: + len = sizeof(struct in6_addr); + break; + default: + return -EOPNOTSUPP; + } + + priv->dreg = nft_parse_register(tb[NFTA_RT_DREG]); + return nft_validate_register_store(ctx, priv->dreg, NULL, + NFT_DATA_VALUE, len); +} + +int nft_rt_get_dump(struct sk_buff *skb, + const struct nft_expr *expr) +{ + const struct nft_rt *priv = nft_expr_priv(expr); + + if (nla_put_be32(skb, NFTA_RT_KEY, htonl(priv->key))) + goto nla_put_failure; + if (nft_dump_register(skb, NFTA_RT_DREG, priv->dreg)) + goto nla_put_failure; + return 0; + +nla_put_failure: + return -1; +} + +static struct nft_expr_type nft_rt_type; +static const struct nft_expr_ops nft_rt_get_ops = { + .type = &nft_rt_type, + .size = NFT_EXPR_SIZE(sizeof(struct nft_rt)), + .eval = nft_rt_get_eval, + .init = nft_rt_get_init, + .dump = nft_rt_get_dump, +}; + +static struct nft_expr_type nft_rt_type __read_mostly = { + .name = "rt", + .ops = &nft_rt_get_ops, + .policy = nft_rt_policy, + .maxattr = NFTA_RT_MAX, + .owner = THIS_MODULE, +}; + +static int __init nft_rt_module_init(void) +{ + return nft_register_expr(&nft_rt_type); +} + +static void __exit nft_rt_module_exit(void) +{ + nft_unregister_expr(&nft_rt_type); +} + +module_init(nft_rt_module_init); +module_exit(nft_rt_module_exit); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Anders K. Pedersen <akp@cohaesio.com>"); +MODULE_ALIAS_NFT_EXPR("rt"); |