| /* |
| * 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 <linux/netfilter_ipv6.h> |
| #include <net/netfilter/nf_tables_core.h> |
| #include <net/netfilter/nf_tables.h> |
| #include <net/netfilter/nft_fib.h> |
| |
| #include <net/ip6_fib.h> |
| #include <net/ip6_route.h> |
| |
| static int get_ifindex(const struct net_device *dev) |
| { |
| return dev ? dev->ifindex : 0; |
| } |
| |
| static int nft_fib6_flowi_init(struct flowi6 *fl6, const struct nft_fib *priv, |
| const struct nft_pktinfo *pkt, |
| const struct net_device *dev, |
| struct ipv6hdr *iph) |
| { |
| int lookup_flags = 0; |
| |
| if (priv->flags & NFTA_FIB_F_DADDR) { |
| fl6->daddr = iph->daddr; |
| fl6->saddr = iph->saddr; |
| } else { |
| fl6->daddr = iph->saddr; |
| fl6->saddr = iph->daddr; |
| } |
| |
| if (ipv6_addr_type(&fl6->daddr) & IPV6_ADDR_LINKLOCAL) { |
| lookup_flags |= RT6_LOOKUP_F_IFACE; |
| fl6->flowi6_oif = get_ifindex(dev ? dev : pkt->skb->dev); |
| } |
| |
| if (ipv6_addr_type(&fl6->saddr) & IPV6_ADDR_UNICAST) |
| lookup_flags |= RT6_LOOKUP_F_HAS_SADDR; |
| |
| if (priv->flags & NFTA_FIB_F_MARK) |
| fl6->flowi6_mark = pkt->skb->mark; |
| |
| fl6->flowlabel = (*(__be32 *)iph) & IPV6_FLOWINFO_MASK; |
| |
| return lookup_flags; |
| } |
| |
| static u32 __nft_fib6_eval_type(const struct nft_fib *priv, |
| const struct nft_pktinfo *pkt, |
| struct ipv6hdr *iph) |
| { |
| const struct net_device *dev = NULL; |
| const struct nf_ipv6_ops *v6ops; |
| int route_err, addrtype; |
| struct rt6_info *rt; |
| struct flowi6 fl6 = { |
| .flowi6_iif = LOOPBACK_IFINDEX, |
| .flowi6_proto = pkt->tprot, |
| }; |
| u32 ret = 0; |
| |
| v6ops = nf_get_ipv6_ops(); |
| if (!v6ops) |
| return RTN_UNREACHABLE; |
| |
| if (priv->flags & NFTA_FIB_F_IIF) |
| dev = nft_in(pkt); |
| else if (priv->flags & NFTA_FIB_F_OIF) |
| dev = nft_out(pkt); |
| |
| nft_fib6_flowi_init(&fl6, priv, pkt, dev, iph); |
| |
| if (dev && v6ops->chk_addr(nft_net(pkt), &fl6.daddr, dev, true)) |
| ret = RTN_LOCAL; |
| |
| route_err = v6ops->route(nft_net(pkt), (struct dst_entry **)&rt, |
| flowi6_to_flowi(&fl6), false); |
| if (route_err) |
| goto err; |
| |
| if (rt->rt6i_flags & RTF_REJECT) { |
| route_err = rt->dst.error; |
| dst_release(&rt->dst); |
| goto err; |
| } |
| |
| if (ipv6_anycast_destination((struct dst_entry *)rt, &fl6.daddr)) |
| ret = RTN_ANYCAST; |
| else if (!dev && rt->rt6i_flags & RTF_LOCAL) |
| ret = RTN_LOCAL; |
| |
| dst_release(&rt->dst); |
| |
| if (ret) |
| return ret; |
| |
| addrtype = ipv6_addr_type(&fl6.daddr); |
| |
| if (addrtype & IPV6_ADDR_MULTICAST) |
| return RTN_MULTICAST; |
| if (addrtype & IPV6_ADDR_UNICAST) |
| return RTN_UNICAST; |
| |
| return RTN_UNSPEC; |
| err: |
| switch (route_err) { |
| case -EINVAL: |
| return RTN_BLACKHOLE; |
| case -EACCES: |
| return RTN_PROHIBIT; |
| case -EAGAIN: |
| return RTN_THROW; |
| default: |
| break; |
| } |
| |
| return RTN_UNREACHABLE; |
| } |
| |
| void nft_fib6_eval_type(const struct nft_expr *expr, struct nft_regs *regs, |
| const struct nft_pktinfo *pkt) |
| { |
| const struct nft_fib *priv = nft_expr_priv(expr); |
| int noff = skb_network_offset(pkt->skb); |
| u32 *dest = ®s->data[priv->dreg]; |
| struct ipv6hdr *iph, _iph; |
| |
| iph = skb_header_pointer(pkt->skb, noff, sizeof(_iph), &_iph); |
| if (!iph) { |
| regs->verdict.code = NFT_BREAK; |
| return; |
| } |
| |
| *dest = __nft_fib6_eval_type(priv, pkt, iph); |
| } |
| EXPORT_SYMBOL_GPL(nft_fib6_eval_type); |
| |
| void nft_fib6_eval(const struct nft_expr *expr, struct nft_regs *regs, |
| const struct nft_pktinfo *pkt) |
| { |
| const struct nft_fib *priv = nft_expr_priv(expr); |
| int noff = skb_network_offset(pkt->skb); |
| const struct net_device *oif = NULL; |
| u32 *dest = ®s->data[priv->dreg]; |
| struct ipv6hdr *iph, _iph; |
| struct flowi6 fl6 = { |
| .flowi6_iif = LOOPBACK_IFINDEX, |
| .flowi6_proto = pkt->tprot, |
| }; |
| struct rt6_info *rt; |
| int lookup_flags; |
| |
| if (priv->flags & NFTA_FIB_F_IIF) |
| oif = nft_in(pkt); |
| else if (priv->flags & NFTA_FIB_F_OIF) |
| oif = nft_out(pkt); |
| |
| iph = skb_header_pointer(pkt->skb, noff, sizeof(_iph), &_iph); |
| if (!iph) { |
| regs->verdict.code = NFT_BREAK; |
| return; |
| } |
| |
| lookup_flags = nft_fib6_flowi_init(&fl6, priv, pkt, oif, iph); |
| |
| if (nft_hook(pkt) == NF_INET_PRE_ROUTING && |
| nft_fib_is_loopback(pkt->skb, nft_in(pkt))) { |
| nft_fib_store_result(dest, priv, pkt, |
| nft_in(pkt)->ifindex); |
| return; |
| } |
| |
| *dest = 0; |
| rt = (void *)ip6_route_lookup(nft_net(pkt), &fl6, pkt->skb, |
| lookup_flags); |
| if (rt->dst.error) |
| goto put_rt_err; |
| |
| /* Should not see RTF_LOCAL here */ |
| if (rt->rt6i_flags & (RTF_REJECT | RTF_ANYCAST | RTF_LOCAL)) |
| goto put_rt_err; |
| |
| if (oif && oif != rt->rt6i_idev->dev) |
| goto put_rt_err; |
| |
| switch (priv->result) { |
| case NFT_FIB_RESULT_OIF: |
| *dest = rt->rt6i_idev->dev->ifindex; |
| break; |
| case NFT_FIB_RESULT_OIFNAME: |
| strncpy((char *)dest, rt->rt6i_idev->dev->name, IFNAMSIZ); |
| break; |
| default: |
| WARN_ON_ONCE(1); |
| break; |
| } |
| |
| put_rt_err: |
| ip6_rt_put(rt); |
| } |
| EXPORT_SYMBOL_GPL(nft_fib6_eval); |
| |
| static struct nft_expr_type nft_fib6_type; |
| |
| static const struct nft_expr_ops nft_fib6_type_ops = { |
| .type = &nft_fib6_type, |
| .size = NFT_EXPR_SIZE(sizeof(struct nft_fib)), |
| .eval = nft_fib6_eval_type, |
| .init = nft_fib_init, |
| .dump = nft_fib_dump, |
| .validate = nft_fib_validate, |
| }; |
| |
| static const struct nft_expr_ops nft_fib6_ops = { |
| .type = &nft_fib6_type, |
| .size = NFT_EXPR_SIZE(sizeof(struct nft_fib)), |
| .eval = nft_fib6_eval, |
| .init = nft_fib_init, |
| .dump = nft_fib_dump, |
| .validate = nft_fib_validate, |
| }; |
| |
| static const struct nft_expr_ops * |
| nft_fib6_select_ops(const struct nft_ctx *ctx, |
| const struct nlattr * const tb[]) |
| { |
| enum nft_fib_result result; |
| |
| if (!tb[NFTA_FIB_RESULT]) |
| return ERR_PTR(-EINVAL); |
| |
| result = ntohl(nla_get_be32(tb[NFTA_FIB_RESULT])); |
| |
| switch (result) { |
| case NFT_FIB_RESULT_OIF: |
| return &nft_fib6_ops; |
| case NFT_FIB_RESULT_OIFNAME: |
| return &nft_fib6_ops; |
| case NFT_FIB_RESULT_ADDRTYPE: |
| return &nft_fib6_type_ops; |
| default: |
| return ERR_PTR(-EOPNOTSUPP); |
| } |
| } |
| |
| static struct nft_expr_type nft_fib6_type __read_mostly = { |
| .name = "fib", |
| .select_ops = nft_fib6_select_ops, |
| .policy = nft_fib_policy, |
| .maxattr = NFTA_FIB_MAX, |
| .family = NFPROTO_IPV6, |
| .owner = THIS_MODULE, |
| }; |
| |
| static int __init nft_fib6_module_init(void) |
| { |
| return nft_register_expr(&nft_fib6_type); |
| } |
| |
| static void __exit nft_fib6_module_exit(void) |
| { |
| nft_unregister_expr(&nft_fib6_type); |
| } |
| module_init(nft_fib6_module_init); |
| module_exit(nft_fib6_module_exit); |
| |
| MODULE_LICENSE("GPL"); |
| MODULE_AUTHOR("Florian Westphal <fw@strlen.de>"); |
| MODULE_ALIAS_NFT_AF_EXPR(10, "fib"); |