diff options
-rw-r--r-- | include/net/netfilter/nft_fib.h | 31 | ||||
-rw-r--r-- | include/uapi/linux/netfilter/nf_tables.h | 36 | ||||
-rw-r--r-- | net/ipv4/netfilter/Kconfig | 8 | ||||
-rw-r--r-- | net/ipv4/netfilter/Makefile | 1 | ||||
-rw-r--r-- | net/ipv4/netfilter/nft_fib_ipv4.c | 238 | ||||
-rw-r--r-- | net/ipv6/netfilter/Kconfig | 8 | ||||
-rw-r--r-- | net/ipv6/netfilter/Makefile | 1 | ||||
-rw-r--r-- | net/ipv6/netfilter/nft_fib_ipv6.c | 275 | ||||
-rw-r--r-- | net/netfilter/Kconfig | 13 | ||||
-rw-r--r-- | net/netfilter/Makefile | 2 | ||||
-rw-r--r-- | net/netfilter/nft_fib.c | 159 | ||||
-rw-r--r-- | net/netfilter/nft_fib_inet.c | 82 |
12 files changed, 854 insertions, 0 deletions
diff --git a/include/net/netfilter/nft_fib.h b/include/net/netfilter/nft_fib.h new file mode 100644 index 000000000000..cbedda077db2 --- /dev/null +++ b/include/net/netfilter/nft_fib.h @@ -0,0 +1,31 @@ +#ifndef _NFT_FIB_H_ +#define _NFT_FIB_H_ + +struct nft_fib { + enum nft_registers dreg:8; + u8 result; + u32 flags; +}; + +extern const struct nla_policy nft_fib_policy[]; + +int nft_fib_dump(struct sk_buff *skb, const struct nft_expr *expr); +int nft_fib_init(const struct nft_ctx *ctx, const struct nft_expr *expr, + const struct nlattr * const tb[]); +int nft_fib_validate(const struct nft_ctx *ctx, const struct nft_expr *expr, + const struct nft_data **data); + + +void nft_fib4_eval_type(const struct nft_expr *expr, struct nft_regs *regs, + const struct nft_pktinfo *pkt); +void nft_fib4_eval(const struct nft_expr *expr, struct nft_regs *regs, + const struct nft_pktinfo *pkt); + +void nft_fib6_eval_type(const struct nft_expr *expr, struct nft_regs *regs, + const struct nft_pktinfo *pkt); +void nft_fib6_eval(const struct nft_expr *expr, struct nft_regs *regs, + const struct nft_pktinfo *pkt); + +void nft_fib_store_result(void *reg, enum nft_fib_result r, + const struct nft_pktinfo *pkt, int index); +#endif diff --git a/include/uapi/linux/netfilter/nf_tables.h b/include/uapi/linux/netfilter/nf_tables.h index c6c4477c136b..a054ad2c8853 100644 --- a/include/uapi/linux/netfilter/nf_tables.h +++ b/include/uapi/linux/netfilter/nf_tables.h @@ -1109,6 +1109,42 @@ enum nft_gen_attributes { }; #define NFTA_GEN_MAX (__NFTA_GEN_MAX - 1) +/* + * enum nft_fib_attributes - nf_tables fib expression netlink attributes + * + * @NFTA_FIB_DREG: destination register (NLA_U32) + * @NFTA_FIB_RESULT: desired result (NLA_U32) + * @NFTA_FIB_FLAGS: flowi fields to initialize when querying the FIB (NLA_U32) + * + * The FIB expression performs a route lookup according + * to the packet data. + */ +enum nft_fib_attributes { + NFTA_FIB_UNSPEC, + NFTA_FIB_DREG, + NFTA_FIB_RESULT, + NFTA_FIB_FLAGS, + __NFTA_FIB_MAX +}; +#define NFTA_FIB_MAX (__NFTA_FIB_MAX - 1) + +enum nft_fib_result { + NFT_FIB_RESULT_UNSPEC, + NFT_FIB_RESULT_OIF, + NFT_FIB_RESULT_OIFNAME, + NFT_FIB_RESULT_ADDRTYPE, + __NFT_FIB_RESULT_MAX +}; +#define NFT_FIB_RESULT_MAX (__NFT_FIB_RESULT_MAX - 1) + +enum nft_fib_flags { + NFTA_FIB_F_SADDR = 1 << 0, /* look up src */ + NFTA_FIB_F_DADDR = 1 << 1, /* look up dst */ + NFTA_FIB_F_MARK = 1 << 2, /* use skb->mark */ + NFTA_FIB_F_IIF = 1 << 3, /* restrict to iif */ + NFTA_FIB_F_OIF = 1 << 4, /* restrict to oif */ +}; + /** * enum nft_trace_attributes - nf_tables trace netlink attributes * diff --git a/net/ipv4/netfilter/Kconfig b/net/ipv4/netfilter/Kconfig index d613309e3e5d..f80bb8f457c8 100644 --- a/net/ipv4/netfilter/Kconfig +++ b/net/ipv4/netfilter/Kconfig @@ -54,6 +54,14 @@ config NFT_DUP_IPV4 help This module enables IPv4 packet duplication support for nf_tables. +config NFT_FIB_IPV4 + select NFT_FIB + tristate "nf_tables fib / ip route lookup support" + help + This module enables IPv4 FIB lookups, e.g. for reverse path filtering. + It also allows query of the FIB for the route type, e.g. local, unicast, + multicast or blackhole. + endif # NF_TABLES_IPV4 config NF_TABLES_ARP diff --git a/net/ipv4/netfilter/Makefile b/net/ipv4/netfilter/Makefile index 853328f8fd05..59d7786ddce1 100644 --- a/net/ipv4/netfilter/Makefile +++ b/net/ipv4/netfilter/Makefile @@ -34,6 +34,7 @@ obj-$(CONFIG_NF_TABLES_IPV4) += nf_tables_ipv4.o obj-$(CONFIG_NFT_CHAIN_ROUTE_IPV4) += nft_chain_route_ipv4.o obj-$(CONFIG_NFT_CHAIN_NAT_IPV4) += nft_chain_nat_ipv4.o obj-$(CONFIG_NFT_REJECT_IPV4) += nft_reject_ipv4.o +obj-$(CONFIG_NFT_FIB_IPV4) += nft_fib_ipv4.o obj-$(CONFIG_NFT_MASQ_IPV4) += nft_masq_ipv4.o obj-$(CONFIG_NFT_REDIR_IPV4) += nft_redir_ipv4.o obj-$(CONFIG_NFT_DUP_IPV4) += nft_dup_ipv4.o diff --git a/net/ipv4/netfilter/nft_fib_ipv4.c b/net/ipv4/netfilter/nft_fib_ipv4.c new file mode 100644 index 000000000000..db91fd42db67 --- /dev/null +++ b/net/ipv4/netfilter/nft_fib_ipv4.c @@ -0,0 +1,238 @@ +/* + * 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_core.h> +#include <net/netfilter/nf_tables.h> +#include <net/netfilter/nft_fib.h> + +#include <net/ip_fib.h> +#include <net/route.h> + +/* don't try to find route from mcast/bcast/zeronet */ +static __be32 get_saddr(__be32 addr) +{ + if (ipv4_is_multicast(addr) || ipv4_is_lbcast(addr) || + ipv4_is_zeronet(addr)) + return 0; + return addr; +} + +static bool fib4_is_local(const struct sk_buff *skb) +{ + const struct rtable *rt = skb_rtable(skb); + + return rt && (rt->rt_flags & RTCF_LOCAL); +} + +#define DSCP_BITS 0xfc + +void nft_fib4_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); + u32 *dst = ®s->data[priv->dreg]; + const struct net_device *dev = NULL; + const struct iphdr *iph; + __be32 addr; + + if (priv->flags & NFTA_FIB_F_IIF) + dev = pkt->in; + else if (priv->flags & NFTA_FIB_F_OIF) + dev = pkt->out; + + iph = ip_hdr(pkt->skb); + if (priv->flags & NFTA_FIB_F_DADDR) + addr = iph->daddr; + else + addr = iph->saddr; + + *dst = inet_dev_addr_type(pkt->net, dev, addr); +} +EXPORT_SYMBOL_GPL(nft_fib4_eval_type); + +static int get_ifindex(const struct net_device *dev) +{ + return dev ? dev->ifindex : 0; +} + +void nft_fib4_eval(const struct nft_expr *expr, struct nft_regs *regs, + const struct nft_pktinfo *pkt) +{ + const struct nft_fib *priv = nft_expr_priv(expr); + u32 *dest = ®s->data[priv->dreg]; + const struct iphdr *iph; + struct fib_result res; + struct flowi4 fl4 = { + .flowi4_scope = RT_SCOPE_UNIVERSE, + .flowi4_iif = LOOPBACK_IFINDEX, + }; + const struct net_device *oif; + struct net_device *found; +#ifdef CONFIG_IP_ROUTE_MULTIPATH + int i; +#endif + + /* + * Do not set flowi4_oif, it restricts results (for example, asking + * for oif 3 will get RTN_UNICAST result even if the daddr exits + * on another interface. + * + * Search results for the desired outinterface instead. + */ + if (priv->flags & NFTA_FIB_F_OIF) + oif = pkt->out; + else if (priv->flags & NFTA_FIB_F_IIF) + oif = pkt->in; + else + oif = NULL; + + if (pkt->hook == NF_INET_PRE_ROUTING && fib4_is_local(pkt->skb)) { + nft_fib_store_result(dest, priv->result, pkt, LOOPBACK_IFINDEX); + return; + } + + iph = ip_hdr(pkt->skb); + if (ipv4_is_multicast(iph->daddr) && + ipv4_is_zeronet(iph->saddr) && + ipv4_is_local_multicast(iph->daddr)) { + nft_fib_store_result(dest, priv->result, pkt, + get_ifindex(pkt->skb->dev)); + return; + } + + if (priv->flags & NFTA_FIB_F_MARK) + fl4.flowi4_mark = pkt->skb->mark; + + fl4.flowi4_tos = iph->tos & DSCP_BITS; + + if (priv->flags & NFTA_FIB_F_DADDR) { + fl4.daddr = iph->daddr; + fl4.saddr = get_saddr(iph->saddr); + } else { + fl4.daddr = iph->saddr; + fl4.saddr = get_saddr(iph->daddr); + } + + if (fib_lookup(pkt->net, &fl4, &res, FIB_LOOKUP_IGNORE_LINKSTATE)) + return; + + switch (res.type) { + case RTN_UNICAST: + break; + case RTN_LOCAL: /* should not appear here, see fib4_is_local() above */ + return; + default: + break; + } + + if (!oif) { + found = FIB_RES_DEV(res); + goto ok; + } + +#ifdef CONFIG_IP_ROUTE_MULTIPATH + for (i = 0; i < res.fi->fib_nhs; i++) { + struct fib_nh *nh = &res.fi->fib_nh[i]; + + if (nh->nh_dev == oif) { + found = nh->nh_dev; + goto ok; + } + } + return; +#else + found = FIB_RES_DEV(res); + if (found != oif) + return; +#endif +ok: + switch (priv->result) { + case NFT_FIB_RESULT_OIF: + *dest = found->ifindex; + break; + case NFT_FIB_RESULT_OIFNAME: + strncpy((char *)dest, found->name, IFNAMSIZ); + break; + default: + WARN_ON_ONCE(1); + break; + } +} +EXPORT_SYMBOL_GPL(nft_fib4_eval); + +static struct nft_expr_type nft_fib4_type; + +static const struct nft_expr_ops nft_fib4_type_ops = { + .type = &nft_fib4_type, + .size = NFT_EXPR_SIZE(sizeof(struct nft_fib)), + .eval = nft_fib4_eval_type, + .init = nft_fib_init, + .dump = nft_fib_dump, + .validate = nft_fib_validate, +}; + +static const struct nft_expr_ops nft_fib4_ops = { + .type = &nft_fib4_type, + .size = NFT_EXPR_SIZE(sizeof(struct nft_fib)), + .eval = nft_fib4_eval, + .init = nft_fib_init, + .dump = nft_fib_dump, + .validate = nft_fib_validate, +}; + +static const struct nft_expr_ops * +nft_fib4_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 = htonl(nla_get_be32(tb[NFTA_FIB_RESULT])); + + switch (result) { + case NFT_FIB_RESULT_OIF: + return &nft_fib4_ops; + case NFT_FIB_RESULT_OIFNAME: + return &nft_fib4_ops; + case NFT_FIB_RESULT_ADDRTYPE: + return &nft_fib4_type_ops; + default: + return ERR_PTR(-EOPNOTSUPP); + } +} + +static struct nft_expr_type nft_fib4_type __read_mostly = { + .name = "fib", + .select_ops = &nft_fib4_select_ops, + .policy = nft_fib_policy, + .maxattr = NFTA_FIB_MAX, + .family = NFPROTO_IPV4, + .owner = THIS_MODULE, +}; + +static int __init nft_fib4_module_init(void) +{ + return nft_register_expr(&nft_fib4_type); +} + +static void __exit nft_fib4_module_exit(void) +{ + nft_unregister_expr(&nft_fib4_type); +} + +module_init(nft_fib4_module_init); +module_exit(nft_fib4_module_exit); +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Florian Westphal <fw@strlen.de>"); +MODULE_ALIAS_NFT_AF_EXPR(2, "fib"); diff --git a/net/ipv6/netfilter/Kconfig b/net/ipv6/netfilter/Kconfig index e10a04c9cdc7..144f1de33836 100644 --- a/net/ipv6/netfilter/Kconfig +++ b/net/ipv6/netfilter/Kconfig @@ -54,6 +54,14 @@ config NFT_DUP_IPV6 help This module enables IPv6 packet duplication support for nf_tables. +config NFT_FIB_IPV6 + tristate "nf_tables fib / ipv6 route lookup support" + select NFT_FIB + help + This module enables IPv6 FIB lookups, e.g. for reverse path filtering. + It also allows query of the FIB for the route type, e.g. local, unicast, + multicast or blackhole. + endif # NF_TABLES_IPV6 endif # NF_TABLES diff --git a/net/ipv6/netfilter/Makefile b/net/ipv6/netfilter/Makefile index b4f7d0b4e2af..7984f3071f05 100644 --- a/net/ipv6/netfilter/Makefile +++ b/net/ipv6/netfilter/Makefile @@ -40,6 +40,7 @@ obj-$(CONFIG_NFT_REJECT_IPV6) += nft_reject_ipv6.o obj-$(CONFIG_NFT_MASQ_IPV6) += nft_masq_ipv6.o obj-$(CONFIG_NFT_REDIR_IPV6) += nft_redir_ipv6.o obj-$(CONFIG_NFT_DUP_IPV6) += nft_dup_ipv6.o +obj-$(CONFIG_NFT_FIB_IPV6) += nft_fib_ipv6.o # matches obj-$(CONFIG_IP6_NF_MATCH_AH) += ip6t_ah.o diff --git a/net/ipv6/netfilter/nft_fib_ipv6.c b/net/ipv6/netfilter/nft_fib_ipv6.c new file mode 100644 index 000000000000..ff1f1b6b4a4a --- /dev/null +++ b/net/ipv6/netfilter/nft_fib_ipv6.c @@ -0,0 +1,275 @@ +/* + * 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 bool fib6_is_local(const struct sk_buff *skb) +{ + const struct rt6_info *rt = (const void *)skb_dst(skb); + + return rt && (rt->rt6i_flags & RTF_LOCAL); +} + +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) +{ + const struct ipv6hdr *iph = ipv6_hdr(pkt->skb); + 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) +{ + const struct net_device *dev = NULL; + const struct nf_ipv6_ops *v6ops; + const struct nf_afinfo *afinfo; + int route_err, addrtype; + struct rt6_info *rt; + struct flowi6 fl6 = { + .flowi6_iif = LOOPBACK_IFINDEX, + .flowi6_proto = pkt->tprot, + }; + u32 ret = 0; + + afinfo = nf_get_afinfo(NFPROTO_IPV6); + if (!afinfo) + return RTN_UNREACHABLE; + + if (priv->flags & NFTA_FIB_F_IIF) + dev = pkt->in; + else if (priv->flags & NFTA_FIB_F_OIF) + dev = pkt->out; + + nft_fib6_flowi_init(&fl6, priv, pkt, dev); + + v6ops = nf_get_ipv6_ops(); + if (dev && v6ops && v6ops->chk_addr(pkt->net, &fl6.daddr, dev, true)) + ret = RTN_LOCAL; + + route_err = afinfo->route(pkt->net, (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); + u32 *dest = ®s->data[priv->dreg]; + + *dest = __nft_fib6_eval_type(priv, pkt); +} +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); + const struct net_device *oif = NULL; + u32 *dest = ®s->data[priv->dreg]; + 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 = pkt->in; + else if (priv->flags & NFTA_FIB_F_OIF) + oif = pkt->out; + + lookup_flags = nft_fib6_flowi_init(&fl6, priv, pkt, oif); + + if (pkt->hook == NF_INET_PRE_ROUTING && fib6_is_local(pkt->skb)) { + nft_fib_store_result(dest, priv->result, pkt, LOOPBACK_IFINDEX); + return; + } + + *dest = 0; + again: + rt = (void *)ip6_route_lookup(pkt->net, &fl6, 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) { + /* multipath route? Try again with F_IFACE */ + if ((lookup_flags & RT6_LOOKUP_F_IFACE) == 0) { + lookup_flags |= RT6_LOOKUP_F_IFACE; + fl6.flowi6_oif = oif->ifindex; + ip6_rt_put(rt); + goto again; + } + } + + 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 = htonl(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"); diff --git a/net/netfilter/Kconfig b/net/netfilter/Kconfig index e8d56d9a4df2..9bcf899ce16e 100644 --- a/net/netfilter/Kconfig +++ b/net/netfilter/Kconfig @@ -581,6 +581,19 @@ config NFT_HASH This option adds the "hash" expression that you can use to perform a hash operation on registers. +config NFT_FIB + tristate + +config NFT_FIB_INET + depends on NF_TABLES_INET + depends on NFT_FIB_IPV4 + depends on NFT_FIB_IPV6 + tristate "Netfilter nf_tables fib inet support" + help + This option allows using the FIB expression from the inet table. + The lookup will be delegated to the IPv4 or IPv6 FIB depending + on the protocol of the packet. + if NF_TABLES_NETDEV config NF_DUP_NETDEV diff --git a/net/netfilter/Makefile b/net/netfilter/Makefile index c23c3c84416f..8faa36c0686d 100644 --- a/net/netfilter/Makefile +++ b/net/netfilter/Makefile @@ -96,6 +96,8 @@ obj-$(CONFIG_NFT_LOG) += nft_log.o obj-$(CONFIG_NFT_MASQ) += nft_masq.o obj-$(CONFIG_NFT_REDIR) += nft_redir.o obj-$(CONFIG_NFT_HASH) += nft_hash.o +obj-$(CONFIG_NFT_FIB) += nft_fib.o +obj-$(CONFIG_NFT_FIB_INET) += nft_fib_inet.o # nf_tables netdev obj-$(CONFIG_NFT_DUP_NETDEV) += nft_dup_netdev.o diff --git a/net/netfilter/nft_fib.c b/net/netfilter/nft_fib.c new file mode 100644 index 000000000000..4944a8b7f7a7 --- /dev/null +++ b/net/netfilter/nft_fib.c @@ -0,0 +1,159 @@ +/* + * 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. + * + * Generic part shared by ipv4 and ipv6 backends. + */ + +#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_core.h> +#include <net/netfilter/nf_tables.h> +#include <net/netfilter/nft_fib.h> + +const struct nla_policy nft_fib_policy[NFTA_FIB_MAX + 1] = { + [NFTA_FIB_DREG] = { .type = NLA_U32 }, + [NFTA_FIB_RESULT] = { .type = NLA_U32 }, + [NFTA_FIB_FLAGS] = { .type = NLA_U32 }, +}; +EXPORT_SYMBOL(nft_fib_policy); + +#define NFTA_FIB_F_ALL (NFTA_FIB_F_SADDR | NFTA_FIB_F_DADDR | \ + NFTA_FIB_F_MARK | NFTA_FIB_F_IIF | NFTA_FIB_F_OIF) + +int nft_fib_validate(const struct nft_ctx *ctx, const struct nft_expr *expr, + const struct nft_data **data) +{ + const struct nft_fib *priv = nft_expr_priv(expr); + unsigned int hooks; + + switch (priv->result) { + case NFT_FIB_RESULT_OIF: /* fallthrough */ + case NFT_FIB_RESULT_OIFNAME: + hooks = (1 << NF_INET_PRE_ROUTING); + break; + case NFT_FIB_RESULT_ADDRTYPE: + if (priv->flags & NFTA_FIB_F_IIF) + hooks = (1 << NF_INET_PRE_ROUTING) | + (1 << NF_INET_LOCAL_IN) | + (1 << NF_INET_FORWARD); + else if (priv->flags & NFTA_FIB_F_OIF) + hooks = (1 << NF_INET_LOCAL_OUT) | + (1 << NF_INET_POST_ROUTING) | + (1 << NF_INET_FORWARD); + else + hooks = (1 << NF_INET_LOCAL_IN) | + (1 << NF_INET_LOCAL_OUT) | + (1 << NF_INET_FORWARD) | + (1 << NF_INET_PRE_ROUTING) | + (1 << NF_INET_POST_ROUTING); + + break; + default: + return -EINVAL; + } + + return nft_chain_validate_hooks(ctx->chain, hooks); +} +EXPORT_SYMBOL_GPL(nft_fib_validate); + +int nft_fib_init(const struct nft_ctx *ctx, const struct nft_expr *expr, + const struct nlattr * const tb[]) +{ + struct nft_fib *priv = nft_expr_priv(expr); + unsigned int len; + int err; + + if (!tb[NFTA_FIB_DREG] || !tb[NFTA_FIB_RESULT] || !tb[NFTA_FIB_FLAGS]) + return -EINVAL; + + priv->flags = ntohl(nla_get_be32(tb[NFTA_FIB_FLAGS])); + + if (priv->flags == 0 || (priv->flags & ~NFTA_FIB_F_ALL)) + return -EINVAL; + + if ((priv->flags & (NFTA_FIB_F_SADDR | NFTA_FIB_F_DADDR)) == + (NFTA_FIB_F_SADDR | NFTA_FIB_F_DADDR)) + return -EINVAL; + if ((priv->flags & (NFTA_FIB_F_IIF | NFTA_FIB_F_OIF)) == + (NFTA_FIB_F_IIF | NFTA_FIB_F_OIF)) + return -EINVAL; + if ((priv->flags & (NFTA_FIB_F_SADDR | NFTA_FIB_F_DADDR)) == 0) + return -EINVAL; + + priv->result = htonl(nla_get_be32(tb[NFTA_FIB_RESULT])); + priv->dreg = nft_parse_register(tb[NFTA_FIB_DREG]); + + switch (priv->result) { + case NFT_FIB_RESULT_OIF: + if (priv->flags & NFTA_FIB_F_OIF) + return -EINVAL; + len = sizeof(int); + break; + case NFT_FIB_RESULT_OIFNAME: + if (priv->flags & NFTA_FIB_F_OIF) + return -EINVAL; + len = IFNAMSIZ; + break; + case NFT_FIB_RESULT_ADDRTYPE: + len = sizeof(u32); + break; + default: + return -EINVAL; + } + + err = nft_validate_register_store(ctx, priv->dreg, NULL, + NFT_DATA_VALUE, len); + if (err < 0) + return err; + + return nft_fib_validate(ctx, expr, NULL); +} +EXPORT_SYMBOL_GPL(nft_fib_init); + +int nft_fib_dump(struct sk_buff *skb, const struct nft_expr *expr) +{ + const struct nft_fib *priv = nft_expr_priv(expr); + + if (nft_dump_register(skb, NFTA_FIB_DREG, priv->dreg)) + return -1; + + if (nla_put_be32(skb, NFTA_FIB_RESULT, htonl(priv->result))) + return -1; + + if (nla_put_be32(skb, NFTA_FIB_FLAGS, htonl(priv->flags))) + return -1; + + return 0; +} +EXPORT_SYMBOL_GPL(nft_fib_dump); + +void nft_fib_store_result(void *reg, enum nft_fib_result r, + const struct nft_pktinfo *pkt, int index) +{ + struct net_device *dev; + u32 *dreg = reg; + + switch (r) { + case NFT_FIB_RESULT_OIF: + *dreg = index; + break; + case NFT_FIB_RESULT_OIFNAME: + dev = dev_get_by_index_rcu(pkt->net, index); + strncpy(reg, dev ? dev->name : "", IFNAMSIZ); + break; + default: + WARN_ON_ONCE(1); + *dreg = 0; + break; + } +} +EXPORT_SYMBOL_GPL(nft_fib_store_result); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Florian Westphal <fw@strlen.de>"); diff --git a/net/netfilter/nft_fib_inet.c b/net/netfilter/nft_fib_inet.c new file mode 100644 index 000000000000..fe8943b572b7 --- /dev/null +++ b/net/netfilter/nft_fib_inet.c @@ -0,0 +1,82 @@ +/* + * 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_core.h> +#include <net/netfilter/nf_tables.h> + +#include <net/netfilter/nft_fib.h> + +static void nft_fib_inet_eval(const struct nft_expr *expr, + struct nft_regs *regs, + const struct nft_pktinfo *pkt) +{ + const struct nft_fib *priv = nft_expr_priv(expr); + + switch (pkt->pf) { + case NFPROTO_IPV4: + switch (priv->result) { + case NFT_FIB_RESULT_OIF: + case NFT_FIB_RESULT_OIFNAME: + return nft_fib4_eval(expr, regs, pkt); + case NFT_FIB_RESULT_ADDRTYPE: + return nft_fib4_eval_type(expr, regs, pkt); + } + break; + case NFPROTO_IPV6: + switch (priv->result) { + case NFT_FIB_RESULT_OIF: + case NFT_FIB_RESULT_OIFNAME: + return nft_fib6_eval(expr, regs, pkt); + case NFT_FIB_RESULT_ADDRTYPE: + return nft_fib6_eval_type(expr, regs, pkt); + } + break; + } + + regs->verdict.code = NF_DROP; +} + +static struct nft_expr_type nft_fib_inet_type; +static const struct nft_expr_ops nft_fib_inet_ops = { + .type = &nft_fib_inet_type, + .size = NFT_EXPR_SIZE(sizeof(struct nft_fib)), + .eval = nft_fib_inet_eval, + .init = nft_fib_init, + .dump = nft_fib_dump, + .validate = nft_fib_validate, +}; + +static struct nft_expr_type nft_fib_inet_type __read_mostly = { + .family = NFPROTO_INET, + .name = "fib", + .ops = &nft_fib_inet_ops, + .policy = nft_fib_policy, + .maxattr = NFTA_FIB_MAX, + .owner = THIS_MODULE, +}; + +static int __init nft_fib_inet_module_init(void) +{ + return nft_register_expr(&nft_fib_inet_type); +} + +static void __exit nft_fib_inet_module_exit(void) +{ + nft_unregister_expr(&nft_fib_inet_type); +} + +module_init(nft_fib_inet_module_init); +module_exit(nft_fib_inet_module_exit); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Florian Westphal <fw@strlen.de>"); +MODULE_ALIAS_NFT_AF_EXPR(1, "fib"); |