From f6d0cbcf09c506b9b022df8f9d7693a7cec3c732 Mon Sep 17 00:00:00 2001 From: Florian Westphal Date: Mon, 24 Oct 2016 16:56:40 +0200 Subject: netfilter: nf_tables: add fib expression Add FIB expression, supported for ipv4, ipv6 and inet family (the latter just dispatches to ipv4 or ipv6 one based on nfproto). Currently supports fetching output interface index/name and the rtm_type associated with an address. This can be used for adding path filtering. rtm_type is useful to e.g. enforce a strong-end host model where packets are only accepted if daddr is configured on the interface the packet arrived on. The fib expression is a native nftables alternative to the xtables addrtype and rp_filter matches. FIB result order for oif/oifname retrieval is as follows: - if packet is local (skb has rtable, RTF_LOCAL set, this will also catch looped-back multicast packets), set oif to the loopback interface. - if fib lookup returns an error, or result points to local, store zero result. This means '--local' option of -m rpfilter is not supported. It is possible to use 'fib type local' or add explicit saddr/daddr matching rules to create exceptions if this is really needed. - store result in the destination register. In case of multiple routes, search set for desired oif in case strict matching is requested. ipv4 and ipv6 behave fib expressions are supposed to behave the same. [ I have collapsed Arnd Bergmann's ("netfilter: nf_tables: fib warnings") http://patchwork.ozlabs.org/patch/688615/ to address fallout from this patch after rebasing nf-next, that was posted to address compilation warnings. --pablo ] Signed-off-by: Florian Westphal Signed-off-by: Pablo Neira Ayuso --- include/net/netfilter/nft_fib.h | 31 +++++++++++++++++++++++++++ include/uapi/linux/netfilter/nf_tables.h | 36 ++++++++++++++++++++++++++++++++ 2 files changed, 67 insertions(+) create mode 100644 include/net/netfilter/nft_fib.h (limited to 'include') 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 * -- cgit v1.2.3 From 1fddf4bad0ac9f4d32c74af286fc1eec2a03c82c Mon Sep 17 00:00:00 2001 From: Pablo Neira Ayuso Date: Thu, 27 Oct 2016 19:49:42 +0100 Subject: netfilter: nf_log: add packet logging for netdev family Move layer 2 packet logging into nf_log_l2packet() that resides in nf_log_common.c, so this can be shared by both bridge and netdev families. This patch adds the boiler plate code to register the netdev logging family. Signed-off-by: Pablo Neira Ayuso --- include/net/netfilter/nf_log.h | 5 +++ net/bridge/netfilter/Kconfig | 1 + net/bridge/netfilter/nf_log_bridge.c | 16 +------- net/netfilter/Kconfig | 4 ++ net/netfilter/Makefile | 3 ++ net/netfilter/nf_log_common.c | 27 ++++++++++++ net/netfilter/nf_log_netdev.c | 80 ++++++++++++++++++++++++++++++++++++ 7 files changed, 121 insertions(+), 15 deletions(-) create mode 100644 net/netfilter/nf_log_netdev.c (limited to 'include') diff --git a/include/net/netfilter/nf_log.h b/include/net/netfilter/nf_log.h index 309cd267be4f..a559aa41253c 100644 --- a/include/net/netfilter/nf_log.h +++ b/include/net/netfilter/nf_log.h @@ -109,5 +109,10 @@ void nf_log_dump_packet_common(struct nf_log_buf *m, u_int8_t pf, const struct net_device *out, const struct nf_loginfo *loginfo, const char *prefix); +void nf_log_l2packet(struct net *net, u_int8_t pf, unsigned int hooknum, + const struct sk_buff *skb, + const struct net_device *in, + const struct net_device *out, + const struct nf_loginfo *loginfo, const char *prefix); #endif /* _NF_LOG_H */ diff --git a/net/bridge/netfilter/Kconfig b/net/bridge/netfilter/Kconfig index 9cebf47ac840..e7ef1a1ef3a6 100644 --- a/net/bridge/netfilter/Kconfig +++ b/net/bridge/netfilter/Kconfig @@ -22,6 +22,7 @@ config NFT_BRIDGE_REJECT config NF_LOG_BRIDGE tristate "Bridge packet logging" + select NF_LOG_COMMON endif # NF_TABLES_BRIDGE diff --git a/net/bridge/netfilter/nf_log_bridge.c b/net/bridge/netfilter/nf_log_bridge.c index 1663df598545..c197b1f844ee 100644 --- a/net/bridge/netfilter/nf_log_bridge.c +++ b/net/bridge/netfilter/nf_log_bridge.c @@ -24,21 +24,7 @@ static void nf_log_bridge_packet(struct net *net, u_int8_t pf, const struct nf_loginfo *loginfo, const char *prefix) { - switch (eth_hdr(skb)->h_proto) { - case htons(ETH_P_IP): - nf_log_packet(net, NFPROTO_IPV4, hooknum, skb, in, out, - loginfo, "%s", prefix); - break; - case htons(ETH_P_IPV6): - nf_log_packet(net, NFPROTO_IPV6, hooknum, skb, in, out, - loginfo, "%s", prefix); - break; - case htons(ETH_P_ARP): - case htons(ETH_P_RARP): - nf_log_packet(net, NFPROTO_ARP, hooknum, skb, in, out, - loginfo, "%s", prefix); - break; - } + nf_log_l2packet(net, pf, hooknum, skb, in, out, loginfo, prefix); } static struct nf_logger nf_bridge_logger __read_mostly = { diff --git a/net/netfilter/Kconfig b/net/netfilter/Kconfig index 9bcf899ce16e..854dadb196a1 100644 --- a/net/netfilter/Kconfig +++ b/net/netfilter/Kconfig @@ -57,6 +57,10 @@ config NF_CONNTRACK config NF_LOG_COMMON tristate +config NF_LOG_NETDEV + tristate "Netdev packet logging" + select NF_LOG_COMMON + if NF_CONNTRACK config NF_CONNTRACK_MARK diff --git a/net/netfilter/Makefile b/net/netfilter/Makefile index 8faa36c0686d..8edd791743fe 100644 --- a/net/netfilter/Makefile +++ b/net/netfilter/Makefile @@ -48,6 +48,9 @@ nf_nat-y := nf_nat_core.o nf_nat_proto_unknown.o nf_nat_proto_common.o \ # generic transport layer logging obj-$(CONFIG_NF_LOG_COMMON) += nf_log_common.o +# packet logging for netdev family +obj-$(CONFIG_NF_LOG_NETDEV) += nf_log_netdev.o + obj-$(CONFIG_NF_NAT) += nf_nat.o obj-$(CONFIG_NF_NAT_REDIRECT) += nf_nat_redirect.o diff --git a/net/netfilter/nf_log_common.c b/net/netfilter/nf_log_common.c index 119fe1cb1ea9..ed9b80815fa0 100644 --- a/net/netfilter/nf_log_common.c +++ b/net/netfilter/nf_log_common.c @@ -175,6 +175,33 @@ nf_log_dump_packet_common(struct nf_log_buf *m, u_int8_t pf, } EXPORT_SYMBOL_GPL(nf_log_dump_packet_common); +/* bridge and netdev logging families share this code. */ +void nf_log_l2packet(struct net *net, u_int8_t pf, + unsigned int hooknum, + const struct sk_buff *skb, + const struct net_device *in, + const struct net_device *out, + const struct nf_loginfo *loginfo, + const char *prefix) +{ + switch (eth_hdr(skb)->h_proto) { + case htons(ETH_P_IP): + nf_log_packet(net, NFPROTO_IPV4, hooknum, skb, in, out, + loginfo, "%s", prefix); + break; + case htons(ETH_P_IPV6): + nf_log_packet(net, NFPROTO_IPV6, hooknum, skb, in, out, + loginfo, "%s", prefix); + break; + case htons(ETH_P_ARP): + case htons(ETH_P_RARP): + nf_log_packet(net, NFPROTO_ARP, hooknum, skb, in, out, + loginfo, "%s", prefix); + break; + } +} +EXPORT_SYMBOL_GPL(nf_log_l2packet); + static int __init nf_log_common_init(void) { return 0; diff --git a/net/netfilter/nf_log_netdev.c b/net/netfilter/nf_log_netdev.c new file mode 100644 index 000000000000..1f645949f3d8 --- /dev/null +++ b/net/netfilter/nf_log_netdev.c @@ -0,0 +1,80 @@ +/* + * (C) 2016 by Pablo Neira Ayuso + * + * 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 +#include +#include +#include +#include + +#include +#include + +static void nf_log_netdev_packet(struct net *net, u_int8_t pf, + unsigned int hooknum, + const struct sk_buff *skb, + const struct net_device *in, + const struct net_device *out, + const struct nf_loginfo *loginfo, + const char *prefix) +{ + nf_log_l2packet(net, pf, hooknum, skb, in, out, loginfo, prefix); +} + +static struct nf_logger nf_netdev_logger __read_mostly = { + .name = "nf_log_netdev", + .type = NF_LOG_TYPE_LOG, + .logfn = nf_log_netdev_packet, + .me = THIS_MODULE, +}; + +static int __net_init nf_log_netdev_net_init(struct net *net) +{ + return nf_log_set(net, NFPROTO_NETDEV, &nf_netdev_logger); +} + +static void __net_exit nf_log_netdev_net_exit(struct net *net) +{ + nf_log_unset(net, &nf_netdev_logger); +} + +static struct pernet_operations nf_log_netdev_net_ops = { + .init = nf_log_netdev_net_init, + .exit = nf_log_netdev_net_exit, +}; + +static int __init nf_log_netdev_init(void) +{ + int ret; + + /* Request to load the real packet loggers. */ + nf_logger_request_module(NFPROTO_IPV4, NF_LOG_TYPE_LOG); + nf_logger_request_module(NFPROTO_IPV6, NF_LOG_TYPE_LOG); + nf_logger_request_module(NFPROTO_ARP, NF_LOG_TYPE_LOG); + + ret = register_pernet_subsys(&nf_log_netdev_net_ops); + if (ret < 0) + return ret; + + nf_log_register(NFPROTO_NETDEV, &nf_netdev_logger); + return 0; +} + +static void __exit nf_log_netdev_exit(void) +{ + unregister_pernet_subsys(&nf_log_netdev_net_ops); + nf_log_unregister(&nf_netdev_logger); +} + +module_init(nf_log_netdev_init); +module_exit(nf_log_netdev_exit); + +MODULE_AUTHOR("Pablo Neira Ayuso "); +MODULE_DESCRIPTION("Netfilter netdev packet logging"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS_NF_LOGGER(5, 0); /* NFPROTO_NETDEV */ -- cgit v1.2.3 From 8db4c5be88f62ffd7a552f70687a10c614dc697b Mon Sep 17 00:00:00 2001 From: Pablo Neira Ayuso Date: Thu, 27 Oct 2016 19:49:48 +0100 Subject: netfilter: move socket lookup infrastructure to nf_socket_ipv{4,6}.c We need this split to reuse existing codebase for the upcoming nf_tables socket expression. Signed-off-by: Pablo Neira Ayuso --- include/net/netfilter/nf_socket.h | 27 ++++ net/ipv4/netfilter/Kconfig | 6 + net/ipv4/netfilter/Makefile | 2 + net/ipv4/netfilter/nf_socket_ipv4.c | 163 +++++++++++++++++++ net/ipv6/netfilter/Kconfig | 6 + net/ipv6/netfilter/Makefile | 2 + net/ipv6/netfilter/nf_socket_ipv6.c | 151 ++++++++++++++++++ net/netfilter/Kconfig | 3 +- net/netfilter/xt_socket.c | 305 ++---------------------------------- 9 files changed, 369 insertions(+), 296 deletions(-) create mode 100644 include/net/netfilter/nf_socket.h create mode 100644 net/ipv4/netfilter/nf_socket_ipv4.c create mode 100644 net/ipv6/netfilter/nf_socket_ipv6.c (limited to 'include') diff --git a/include/net/netfilter/nf_socket.h b/include/net/netfilter/nf_socket.h new file mode 100644 index 000000000000..f2fc39c97d43 --- /dev/null +++ b/include/net/netfilter/nf_socket.h @@ -0,0 +1,27 @@ +#ifndef _NF_SOCK_H_ +#define _NF_SOCK_H_ + +struct net_device; +struct sk_buff; +struct sock; +struct net; + +static inline bool nf_sk_is_transparent(struct sock *sk) +{ + switch (sk->sk_state) { + case TCP_TIME_WAIT: + return inet_twsk(sk)->tw_transparent; + case TCP_NEW_SYN_RECV: + return inet_rsk(inet_reqsk(sk))->no_srccheck; + default: + return inet_sk(sk)->transparent; + } +} + +struct sock *nf_sk_lookup_slow_v4(struct net *net, const struct sk_buff *skb, + const struct net_device *indev); + +struct sock *nf_sk_lookup_slow_v6(struct net *net, const struct sk_buff *skb, + const struct net_device *indev); + +#endif diff --git a/net/ipv4/netfilter/Kconfig b/net/ipv4/netfilter/Kconfig index f80bb8f457c8..c11eb1744ab1 100644 --- a/net/ipv4/netfilter/Kconfig +++ b/net/ipv4/netfilter/Kconfig @@ -25,6 +25,12 @@ config NF_CONNTRACK_IPV4 To compile it as a module, choose M here. If unsure, say N. +config NF_SOCKET_IPV4 + tristate "IPv4 socket lookup support" + help + This option enables the IPv4 socket lookup infrastructure. This is + is required by the iptables socket match. + if NF_TABLES config NF_TABLES_IPV4 diff --git a/net/ipv4/netfilter/Makefile b/net/ipv4/netfilter/Makefile index 59d7786ddce1..f462fee66ac8 100644 --- a/net/ipv4/netfilter/Makefile +++ b/net/ipv4/netfilter/Makefile @@ -14,6 +14,8 @@ obj-$(CONFIG_NF_NAT_IPV4) += nf_nat_ipv4.o # defrag obj-$(CONFIG_NF_DEFRAG_IPV4) += nf_defrag_ipv4.o +obj-$(CONFIG_NF_SOCKET_IPV4) += nf_socket_ipv4.o + # logging obj-$(CONFIG_NF_LOG_ARP) += nf_log_arp.o obj-$(CONFIG_NF_LOG_IPV4) += nf_log_ipv4.o diff --git a/net/ipv4/netfilter/nf_socket_ipv4.c b/net/ipv4/netfilter/nf_socket_ipv4.c new file mode 100644 index 000000000000..a83d558e1aae --- /dev/null +++ b/net/ipv4/netfilter/nf_socket_ipv4.c @@ -0,0 +1,163 @@ +/* + * Copyright (C) 2007-2008 BalaBit IT Ltd. + * Author: Krisztian Kovacs + * + * 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. + * + */ +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt +#include +#include +#include +#include +#include +#include +#include +#include +#if IS_ENABLED(CONFIG_NF_CONNTRACK) +#include +#endif + +static int +extract_icmp4_fields(const struct sk_buff *skb, u8 *protocol, + __be32 *raddr, __be32 *laddr, + __be16 *rport, __be16 *lport) +{ + unsigned int outside_hdrlen = ip_hdrlen(skb); + struct iphdr *inside_iph, _inside_iph; + struct icmphdr *icmph, _icmph; + __be16 *ports, _ports[2]; + + icmph = skb_header_pointer(skb, outside_hdrlen, + sizeof(_icmph), &_icmph); + if (icmph == NULL) + return 1; + + switch (icmph->type) { + case ICMP_DEST_UNREACH: + case ICMP_SOURCE_QUENCH: + case ICMP_REDIRECT: + case ICMP_TIME_EXCEEDED: + case ICMP_PARAMETERPROB: + break; + default: + return 1; + } + + inside_iph = skb_header_pointer(skb, outside_hdrlen + + sizeof(struct icmphdr), + sizeof(_inside_iph), &_inside_iph); + if (inside_iph == NULL) + return 1; + + if (inside_iph->protocol != IPPROTO_TCP && + inside_iph->protocol != IPPROTO_UDP) + return 1; + + ports = skb_header_pointer(skb, outside_hdrlen + + sizeof(struct icmphdr) + + (inside_iph->ihl << 2), + sizeof(_ports), &_ports); + if (ports == NULL) + return 1; + + /* the inside IP packet is the one quoted from our side, thus + * its saddr is the local address */ + *protocol = inside_iph->protocol; + *laddr = inside_iph->saddr; + *lport = ports[0]; + *raddr = inside_iph->daddr; + *rport = ports[1]; + + return 0; +} + +static struct sock * +nf_socket_get_sock_v4(struct net *net, struct sk_buff *skb, const int doff, + const u8 protocol, + const __be32 saddr, const __be32 daddr, + const __be16 sport, const __be16 dport, + const struct net_device *in) +{ + switch (protocol) { + case IPPROTO_TCP: + return inet_lookup(net, &tcp_hashinfo, skb, doff, + saddr, sport, daddr, dport, + in->ifindex); + case IPPROTO_UDP: + return udp4_lib_lookup(net, saddr, sport, daddr, dport, + in->ifindex); + } + return NULL; +} + +struct sock *nf_sk_lookup_slow_v4(struct net *net, const struct sk_buff *skb, + const struct net_device *indev) +{ + __be32 uninitialized_var(daddr), uninitialized_var(saddr); + __be16 uninitialized_var(dport), uninitialized_var(sport); + const struct iphdr *iph = ip_hdr(skb); + struct sk_buff *data_skb = NULL; + u8 uninitialized_var(protocol); +#if IS_ENABLED(CONFIG_NF_CONNTRACK) + enum ip_conntrack_info ctinfo; + struct nf_conn const *ct; +#endif + int doff = 0; + + if (iph->protocol == IPPROTO_UDP || iph->protocol == IPPROTO_TCP) { + struct udphdr _hdr, *hp; + + hp = skb_header_pointer(skb, ip_hdrlen(skb), + sizeof(_hdr), &_hdr); + if (hp == NULL) + return NULL; + + protocol = iph->protocol; + saddr = iph->saddr; + sport = hp->source; + daddr = iph->daddr; + dport = hp->dest; + data_skb = (struct sk_buff *)skb; + doff = iph->protocol == IPPROTO_TCP ? + ip_hdrlen(skb) + __tcp_hdrlen((struct tcphdr *)hp) : + ip_hdrlen(skb) + sizeof(*hp); + + } else if (iph->protocol == IPPROTO_ICMP) { + if (extract_icmp4_fields(skb, &protocol, &saddr, &daddr, + &sport, &dport)) + return NULL; + } else { + return NULL; + } + +#if IS_ENABLED(CONFIG_NF_CONNTRACK) + /* Do the lookup with the original socket address in + * case this is a reply packet of an established + * SNAT-ted connection. + */ + ct = nf_ct_get(skb, &ctinfo); + if (ct && !nf_ct_is_untracked(ct) && + ((iph->protocol != IPPROTO_ICMP && + ctinfo == IP_CT_ESTABLISHED_REPLY) || + (iph->protocol == IPPROTO_ICMP && + ctinfo == IP_CT_RELATED_REPLY)) && + (ct->status & IPS_SRC_NAT_DONE)) { + + daddr = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.u3.ip; + dport = (iph->protocol == IPPROTO_TCP) ? + ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.u.tcp.port : + ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.u.udp.port; + } +#endif + + return nf_socket_get_sock_v4(net, data_skb, doff, protocol, saddr, + daddr, sport, dport, indev); +} +EXPORT_SYMBOL_GPL(nf_sk_lookup_slow_v4); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Krisztian Kovacs, Balazs Scheidler"); +MODULE_DESCRIPTION("Netfilter IPv4 socket lookup infrastructure"); diff --git a/net/ipv6/netfilter/Kconfig b/net/ipv6/netfilter/Kconfig index 144f1de33836..6acb2eecd986 100644 --- a/net/ipv6/netfilter/Kconfig +++ b/net/ipv6/netfilter/Kconfig @@ -25,6 +25,12 @@ config NF_CONNTRACK_IPV6 To compile it as a module, choose M here. If unsure, say N. +config NF_SOCKET_IPV6 + tristate "IPv6 socket lookup support" + help + This option enables the IPv6 socket lookup infrastructure. This + is used by the ip6tables socket match. + if NF_TABLES config NF_TABLES_IPV6 diff --git a/net/ipv6/netfilter/Makefile b/net/ipv6/netfilter/Makefile index 7984f3071f05..fe180c96040e 100644 --- a/net/ipv6/netfilter/Makefile +++ b/net/ipv6/netfilter/Makefile @@ -24,6 +24,8 @@ obj-$(CONFIG_NF_NAT_MASQUERADE_IPV6) += nf_nat_masquerade_ipv6.o nf_defrag_ipv6-y := nf_defrag_ipv6_hooks.o nf_conntrack_reasm.o obj-$(CONFIG_NF_DEFRAG_IPV6) += nf_defrag_ipv6.o +obj-$(CONFIG_NF_SOCKET_IPV6) += nf_socket_ipv6.o + # logging obj-$(CONFIG_NF_LOG_IPV6) += nf_log_ipv6.o diff --git a/net/ipv6/netfilter/nf_socket_ipv6.c b/net/ipv6/netfilter/nf_socket_ipv6.c new file mode 100644 index 000000000000..ebb2bf84232a --- /dev/null +++ b/net/ipv6/netfilter/nf_socket_ipv6.c @@ -0,0 +1,151 @@ +/* + * Copyright (C) 2007-2008 BalaBit IT Ltd. + * Author: Krisztian Kovacs + * + * 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. + * + */ +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#if IS_ENABLED(CONFIG_NF_CONNTRACK) +#include +#endif + +static int +extract_icmp6_fields(const struct sk_buff *skb, + unsigned int outside_hdrlen, + int *protocol, + const struct in6_addr **raddr, + const struct in6_addr **laddr, + __be16 *rport, + __be16 *lport, + struct ipv6hdr *ipv6_var) +{ + const struct ipv6hdr *inside_iph; + struct icmp6hdr *icmph, _icmph; + __be16 *ports, _ports[2]; + u8 inside_nexthdr; + __be16 inside_fragoff; + int inside_hdrlen; + + icmph = skb_header_pointer(skb, outside_hdrlen, + sizeof(_icmph), &_icmph); + if (icmph == NULL) + return 1; + + if (icmph->icmp6_type & ICMPV6_INFOMSG_MASK) + return 1; + + inside_iph = skb_header_pointer(skb, outside_hdrlen + sizeof(_icmph), + sizeof(*ipv6_var), ipv6_var); + if (inside_iph == NULL) + return 1; + inside_nexthdr = inside_iph->nexthdr; + + inside_hdrlen = ipv6_skip_exthdr(skb, outside_hdrlen + sizeof(_icmph) + + sizeof(*ipv6_var), + &inside_nexthdr, &inside_fragoff); + if (inside_hdrlen < 0) + return 1; /* hjm: Packet has no/incomplete transport layer headers. */ + + if (inside_nexthdr != IPPROTO_TCP && + inside_nexthdr != IPPROTO_UDP) + return 1; + + ports = skb_header_pointer(skb, inside_hdrlen, + sizeof(_ports), &_ports); + if (ports == NULL) + return 1; + + /* the inside IP packet is the one quoted from our side, thus + * its saddr is the local address */ + *protocol = inside_nexthdr; + *laddr = &inside_iph->saddr; + *lport = ports[0]; + *raddr = &inside_iph->daddr; + *rport = ports[1]; + + return 0; +} + +static struct sock * +nf_socket_get_sock_v6(struct net *net, struct sk_buff *skb, int doff, + const u8 protocol, + const struct in6_addr *saddr, const struct in6_addr *daddr, + const __be16 sport, const __be16 dport, + const struct net_device *in) +{ + switch (protocol) { + case IPPROTO_TCP: + return inet6_lookup(net, &tcp_hashinfo, skb, doff, + saddr, sport, daddr, dport, + in->ifindex); + case IPPROTO_UDP: + return udp6_lib_lookup(net, saddr, sport, daddr, dport, + in->ifindex); + } + + return NULL; +} + +struct sock *nf_sk_lookup_slow_v6(struct net *net, const struct sk_buff *skb, + const struct net_device *indev) +{ + __be16 uninitialized_var(dport), uninitialized_var(sport); + const struct in6_addr *daddr = NULL, *saddr = NULL; + struct ipv6hdr *iph = ipv6_hdr(skb); + struct sk_buff *data_skb = NULL; + int doff = 0; + int thoff = 0, tproto; + + tproto = ipv6_find_hdr(skb, &thoff, -1, NULL, NULL); + if (tproto < 0) { + pr_debug("unable to find transport header in IPv6 packet, dropping\n"); + return NULL; + } + + if (tproto == IPPROTO_UDP || tproto == IPPROTO_TCP) { + struct udphdr _hdr, *hp; + + hp = skb_header_pointer(skb, thoff, sizeof(_hdr), &_hdr); + if (hp == NULL) + return NULL; + + saddr = &iph->saddr; + sport = hp->source; + daddr = &iph->daddr; + dport = hp->dest; + data_skb = (struct sk_buff *)skb; + doff = tproto == IPPROTO_TCP ? + thoff + __tcp_hdrlen((struct tcphdr *)hp) : + thoff + sizeof(*hp); + + } else if (tproto == IPPROTO_ICMPV6) { + struct ipv6hdr ipv6_var; + + if (extract_icmp6_fields(skb, thoff, &tproto, &saddr, &daddr, + &sport, &dport, &ipv6_var)) + return NULL; + } else { + return NULL; + } + + return nf_socket_get_sock_v6(net, data_skb, doff, tproto, saddr, daddr, + sport, dport, indev); +} +EXPORT_SYMBOL_GPL(nf_sk_lookup_slow_v6); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Krisztian Kovacs, Balazs Scheidler"); +MODULE_DESCRIPTION("Netfilter IPv6 socket lookup infrastructure"); diff --git a/net/netfilter/Kconfig b/net/netfilter/Kconfig index 854dadb196a1..ed00ec114ea2 100644 --- a/net/netfilter/Kconfig +++ b/net/netfilter/Kconfig @@ -1426,9 +1426,10 @@ config NETFILTER_XT_MATCH_SOCKET tristate '"socket" match support' depends on NETFILTER_XTABLES depends on NETFILTER_ADVANCED - depends on !NF_CONNTRACK || NF_CONNTRACK depends on IPV6 || IPV6=n depends on IP6_NF_IPTABLES || IP6_NF_IPTABLES=n + depends on NF_SOCKET_IPV4 + depends on NF_SOCKET_IPV6 select NF_DEFRAG_IPV4 select NF_DEFRAG_IPV6 if IP6_NF_IPTABLES != n help diff --git a/net/netfilter/xt_socket.c b/net/netfilter/xt_socket.c index b10ade272b50..018c369c9f0d 100644 --- a/net/netfilter/xt_socket.c +++ b/net/netfilter/xt_socket.c @@ -22,76 +22,14 @@ #include #if IS_ENABLED(CONFIG_IP6_NF_IPTABLES) -#define XT_SOCKET_HAVE_IPV6 1 #include #include #include #endif +#include #include -#if IS_ENABLED(CONFIG_NF_CONNTRACK) -#define XT_SOCKET_HAVE_CONNTRACK 1 -#include -#endif - -static int -extract_icmp4_fields(const struct sk_buff *skb, - u8 *protocol, - __be32 *raddr, - __be32 *laddr, - __be16 *rport, - __be16 *lport) -{ - unsigned int outside_hdrlen = ip_hdrlen(skb); - struct iphdr *inside_iph, _inside_iph; - struct icmphdr *icmph, _icmph; - __be16 *ports, _ports[2]; - - icmph = skb_header_pointer(skb, outside_hdrlen, - sizeof(_icmph), &_icmph); - if (icmph == NULL) - return 1; - - switch (icmph->type) { - case ICMP_DEST_UNREACH: - case ICMP_SOURCE_QUENCH: - case ICMP_REDIRECT: - case ICMP_TIME_EXCEEDED: - case ICMP_PARAMETERPROB: - break; - default: - return 1; - } - - inside_iph = skb_header_pointer(skb, outside_hdrlen + - sizeof(struct icmphdr), - sizeof(_inside_iph), &_inside_iph); - if (inside_iph == NULL) - return 1; - - if (inside_iph->protocol != IPPROTO_TCP && - inside_iph->protocol != IPPROTO_UDP) - return 1; - - ports = skb_header_pointer(skb, outside_hdrlen + - sizeof(struct icmphdr) + - (inside_iph->ihl << 2), - sizeof(_ports), &_ports); - if (ports == NULL) - return 1; - - /* the inside IP packet is the one quoted from our side, thus - * its saddr is the local address */ - *protocol = inside_iph->protocol; - *laddr = inside_iph->saddr; - *lport = ports[0]; - *raddr = inside_iph->daddr; - *rport = ports[1]; - - return 0; -} - /* "socket" match based redirection (no specific rule) * =================================================== * @@ -111,104 +49,6 @@ extract_icmp4_fields(const struct sk_buff *skb, * then local services could intercept traffic going through the * box. */ -static struct sock * -xt_socket_get_sock_v4(struct net *net, struct sk_buff *skb, const int doff, - const u8 protocol, - const __be32 saddr, const __be32 daddr, - const __be16 sport, const __be16 dport, - const struct net_device *in) -{ - switch (protocol) { - case IPPROTO_TCP: - return inet_lookup(net, &tcp_hashinfo, skb, doff, - saddr, sport, daddr, dport, - in->ifindex); - case IPPROTO_UDP: - return udp4_lib_lookup(net, saddr, sport, daddr, dport, - in->ifindex); - } - return NULL; -} - -static bool xt_socket_sk_is_transparent(struct sock *sk) -{ - switch (sk->sk_state) { - case TCP_TIME_WAIT: - return inet_twsk(sk)->tw_transparent; - - case TCP_NEW_SYN_RECV: - return inet_rsk(inet_reqsk(sk))->no_srccheck; - - default: - return inet_sk(sk)->transparent; - } -} - -static struct sock *xt_socket_lookup_slow_v4(struct net *net, - const struct sk_buff *skb, - const struct net_device *indev) -{ - const struct iphdr *iph = ip_hdr(skb); - struct sk_buff *data_skb = NULL; - int doff = 0; - __be32 uninitialized_var(daddr), uninitialized_var(saddr); - __be16 uninitialized_var(dport), uninitialized_var(sport); - u8 uninitialized_var(protocol); -#ifdef XT_SOCKET_HAVE_CONNTRACK - struct nf_conn const *ct; - enum ip_conntrack_info ctinfo; -#endif - - if (iph->protocol == IPPROTO_UDP || iph->protocol == IPPROTO_TCP) { - struct udphdr _hdr, *hp; - - hp = skb_header_pointer(skb, ip_hdrlen(skb), - sizeof(_hdr), &_hdr); - if (hp == NULL) - return NULL; - - protocol = iph->protocol; - saddr = iph->saddr; - sport = hp->source; - daddr = iph->daddr; - dport = hp->dest; - data_skb = (struct sk_buff *)skb; - doff = iph->protocol == IPPROTO_TCP ? - ip_hdrlen(skb) + __tcp_hdrlen((struct tcphdr *)hp) : - ip_hdrlen(skb) + sizeof(*hp); - - } else if (iph->protocol == IPPROTO_ICMP) { - if (extract_icmp4_fields(skb, &protocol, &saddr, &daddr, - &sport, &dport)) - return NULL; - } else { - return NULL; - } - -#ifdef XT_SOCKET_HAVE_CONNTRACK - /* Do the lookup with the original socket address in - * case this is a reply packet of an established - * SNAT-ted connection. - */ - ct = nf_ct_get(skb, &ctinfo); - if (ct && !nf_ct_is_untracked(ct) && - ((iph->protocol != IPPROTO_ICMP && - ctinfo == IP_CT_ESTABLISHED_REPLY) || - (iph->protocol == IPPROTO_ICMP && - ctinfo == IP_CT_RELATED_REPLY)) && - (ct->status & IPS_SRC_NAT_DONE)) { - - daddr = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.u3.ip; - dport = (iph->protocol == IPPROTO_TCP) ? - ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.u.tcp.port : - ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.u.udp.port; - } -#endif - - return xt_socket_get_sock_v4(net, data_skb, doff, protocol, saddr, - daddr, sport, dport, indev); -} - static bool socket_match(const struct sk_buff *skb, struct xt_action_param *par, const struct xt_socket_mtinfo1 *info) @@ -217,7 +57,7 @@ socket_match(const struct sk_buff *skb, struct xt_action_param *par, struct sock *sk = skb->sk; if (!sk) - sk = xt_socket_lookup_slow_v4(par->net, skb, par->in); + sk = nf_sk_lookup_slow_v4(par->net, skb, par->in); if (sk) { bool wildcard; bool transparent = true; @@ -233,7 +73,7 @@ socket_match(const struct sk_buff *skb, struct xt_action_param *par, * if XT_SOCKET_TRANSPARENT is used */ if (info->flags & XT_SOCKET_TRANSPARENT) - transparent = xt_socket_sk_is_transparent(sk); + transparent = nf_sk_is_transparent(sk); if (info->flags & XT_SOCKET_RESTORESKMARK && !wildcard && transparent) @@ -265,132 +105,7 @@ socket_mt4_v1_v2_v3(const struct sk_buff *skb, struct xt_action_param *par) return socket_match(skb, par, par->matchinfo); } -#ifdef XT_SOCKET_HAVE_IPV6 - -static int -extract_icmp6_fields(const struct sk_buff *skb, - unsigned int outside_hdrlen, - int *protocol, - const struct in6_addr **raddr, - const struct in6_addr **laddr, - __be16 *rport, - __be16 *lport, - struct ipv6hdr *ipv6_var) -{ - const struct ipv6hdr *inside_iph; - struct icmp6hdr *icmph, _icmph; - __be16 *ports, _ports[2]; - u8 inside_nexthdr; - __be16 inside_fragoff; - int inside_hdrlen; - - icmph = skb_header_pointer(skb, outside_hdrlen, - sizeof(_icmph), &_icmph); - if (icmph == NULL) - return 1; - - if (icmph->icmp6_type & ICMPV6_INFOMSG_MASK) - return 1; - - inside_iph = skb_header_pointer(skb, outside_hdrlen + sizeof(_icmph), - sizeof(*ipv6_var), ipv6_var); - if (inside_iph == NULL) - return 1; - inside_nexthdr = inside_iph->nexthdr; - - inside_hdrlen = ipv6_skip_exthdr(skb, outside_hdrlen + sizeof(_icmph) + - sizeof(*ipv6_var), - &inside_nexthdr, &inside_fragoff); - if (inside_hdrlen < 0) - return 1; /* hjm: Packet has no/incomplete transport layer headers. */ - - if (inside_nexthdr != IPPROTO_TCP && - inside_nexthdr != IPPROTO_UDP) - return 1; - - ports = skb_header_pointer(skb, inside_hdrlen, - sizeof(_ports), &_ports); - if (ports == NULL) - return 1; - - /* the inside IP packet is the one quoted from our side, thus - * its saddr is the local address */ - *protocol = inside_nexthdr; - *laddr = &inside_iph->saddr; - *lport = ports[0]; - *raddr = &inside_iph->daddr; - *rport = ports[1]; - - return 0; -} - -static struct sock * -xt_socket_get_sock_v6(struct net *net, struct sk_buff *skb, int doff, - const u8 protocol, - const struct in6_addr *saddr, const struct in6_addr *daddr, - const __be16 sport, const __be16 dport, - const struct net_device *in) -{ - switch (protocol) { - case IPPROTO_TCP: - return inet6_lookup(net, &tcp_hashinfo, skb, doff, - saddr, sport, daddr, dport, - in->ifindex); - case IPPROTO_UDP: - return udp6_lib_lookup(net, saddr, sport, daddr, dport, - in->ifindex); - } - - return NULL; -} - -static struct sock *xt_socket_lookup_slow_v6(struct net *net, - const struct sk_buff *skb, - const struct net_device *indev) -{ - __be16 uninitialized_var(dport), uninitialized_var(sport); - const struct in6_addr *daddr = NULL, *saddr = NULL; - struct ipv6hdr *iph = ipv6_hdr(skb); - struct sk_buff *data_skb = NULL; - int doff = 0; - int thoff = 0, tproto; - - tproto = ipv6_find_hdr(skb, &thoff, -1, NULL, NULL); - if (tproto < 0) { - pr_debug("unable to find transport header in IPv6 packet, dropping\n"); - return NULL; - } - - if (tproto == IPPROTO_UDP || tproto == IPPROTO_TCP) { - struct udphdr _hdr, *hp; - - hp = skb_header_pointer(skb, thoff, sizeof(_hdr), &_hdr); - if (hp == NULL) - return NULL; - - saddr = &iph->saddr; - sport = hp->source; - daddr = &iph->daddr; - dport = hp->dest; - data_skb = (struct sk_buff *)skb; - doff = tproto == IPPROTO_TCP ? - thoff + __tcp_hdrlen((struct tcphdr *)hp) : - thoff + sizeof(*hp); - - } else if (tproto == IPPROTO_ICMPV6) { - struct ipv6hdr ipv6_var; - - if (extract_icmp6_fields(skb, thoff, &tproto, &saddr, &daddr, - &sport, &dport, &ipv6_var)) - return NULL; - } else { - return NULL; - } - - return xt_socket_get_sock_v6(net, data_skb, doff, tproto, saddr, daddr, - sport, dport, indev); -} - +#if IS_ENABLED(CONFIG_IP6_NF_IPTABLES) static bool socket_mt6_v1_v2_v3(const struct sk_buff *skb, struct xt_action_param *par) { @@ -399,7 +114,7 @@ socket_mt6_v1_v2_v3(const struct sk_buff *skb, struct xt_action_param *par) struct sock *sk = skb->sk; if (!sk) - sk = xt_socket_lookup_slow_v6(par->net, skb, par->in); + sk = nf_sk_lookup_slow_v6(par->net, skb, par->in); if (sk) { bool wildcard; bool transparent = true; @@ -415,7 +130,7 @@ socket_mt6_v1_v2_v3(const struct sk_buff *skb, struct xt_action_param *par) * if XT_SOCKET_TRANSPARENT is used */ if (info->flags & XT_SOCKET_TRANSPARENT) - transparent = xt_socket_sk_is_transparent(sk); + transparent = nf_sk_is_transparent(sk); if (info->flags & XT_SOCKET_RESTORESKMARK && !wildcard && transparent) @@ -488,7 +203,7 @@ static struct xt_match socket_mt_reg[] __read_mostly = { (1 << NF_INET_LOCAL_IN), .me = THIS_MODULE, }, -#ifdef XT_SOCKET_HAVE_IPV6 +#if IS_ENABLED(CONFIG_IP6_NF_IPTABLES) { .name = "socket", .revision = 1, @@ -512,7 +227,7 @@ static struct xt_match socket_mt_reg[] __read_mostly = { (1 << NF_INET_LOCAL_IN), .me = THIS_MODULE, }, -#ifdef XT_SOCKET_HAVE_IPV6 +#if IS_ENABLED(CONFIG_IP6_NF_IPTABLES) { .name = "socket", .revision = 2, @@ -536,7 +251,7 @@ static struct xt_match socket_mt_reg[] __read_mostly = { (1 << NF_INET_LOCAL_IN), .me = THIS_MODULE, }, -#ifdef XT_SOCKET_HAVE_IPV6 +#if IS_ENABLED(CONFIG_IP6_NF_IPTABLES) { .name = "socket", .revision = 3, @@ -554,7 +269,7 @@ static struct xt_match socket_mt_reg[] __read_mostly = { static int __init socket_mt_init(void) { nf_defrag_ipv4_enable(); -#ifdef XT_SOCKET_HAVE_IPV6 +#if IS_ENABLED(CONFIG_IP6_NF_IPTABLES) nf_defrag_ipv6_enable(); #endif -- cgit v1.2.3 From 2fa841938c648fe4359691f41e8e1f37ff1a3aa2 Mon Sep 17 00:00:00 2001 From: "Anders K. Pedersen" Date: Fri, 28 Oct 2016 05:54:15 +0000 Subject: netfilter: nf_tables: introduce routing expression Introduces an nftables rt expression for routing related data with support for nexthop (i.e. the directly connected IP address that an outgoing packet is sent to), which can be used either for matching or accounting, eg. # nft add rule filter postrouting \ ip daddr 192.168.1.0/24 rt nexthop != 192.168.0.1 drop This will drop any traffic to 192.168.1.0/24 that is not routed via 192.168.0.1. # nft add rule filter postrouting \ flow table acct { rt nexthop timeout 600s counter } # nft add rule ip6 filter postrouting \ flow table acct { rt nexthop timeout 600s counter } These rules count outgoing traffic per nexthop. Note that the timeout releases an entry if no traffic is seen for this nexthop within 10 minutes. # nft add rule inet filter postrouting \ ether type ip \ flow table acct { rt nexthop timeout 600s counter } # nft add rule inet filter postrouting \ ether type ip6 \ flow table acct { rt nexthop timeout 600s counter } Same as above, but via the inet family, where the ether type must be specified explicitly. "rt classid" is also implemented identical to "meta rtclassid", since it is more logical to have this match in the routing expression going forward. Signed-off-by: Anders K. Pedersen Signed-off-by: Pablo Neira Ayuso --- include/uapi/linux/netfilter/nf_tables.h | 27 ++++++ net/netfilter/Kconfig | 6 ++ net/netfilter/Makefile | 1 + net/netfilter/nft_rt.c | 153 +++++++++++++++++++++++++++++++ 4 files changed, 187 insertions(+) create mode 100644 net/netfilter/nft_rt.c (limited to 'include') diff --git a/include/uapi/linux/netfilter/nf_tables.h b/include/uapi/linux/netfilter/nf_tables.h index a054ad2c8853..14e5f619167e 100644 --- a/include/uapi/linux/netfilter/nf_tables.h +++ b/include/uapi/linux/netfilter/nf_tables.h @@ -758,6 +758,19 @@ enum nft_meta_keys { NFT_META_PRANDOM, }; +/** + * enum nft_rt_keys - nf_tables routing expression keys + * + * @NFT_RT_CLASSID: realm value of packet's route (skb->dst->tclassid) + * @NFT_RT_NEXTHOP4: routing nexthop for IPv4 + * @NFT_RT_NEXTHOP6: routing nexthop for IPv6 + */ +enum nft_rt_keys { + NFT_RT_CLASSID, + NFT_RT_NEXTHOP4, + NFT_RT_NEXTHOP6, +}; + /** * enum nft_hash_attributes - nf_tables hash expression netlink attributes * @@ -796,6 +809,20 @@ enum nft_meta_attributes { }; #define NFTA_META_MAX (__NFTA_META_MAX - 1) +/** + * enum nft_rt_attributes - nf_tables routing expression netlink attributes + * + * @NFTA_RT_DREG: destination register (NLA_U32) + * @NFTA_RT_KEY: routing data item to load (NLA_U32: nft_rt_keys) + */ +enum nft_rt_attributes { + NFTA_RT_UNSPEC, + NFTA_RT_DREG, + NFTA_RT_KEY, + __NFTA_RT_MAX +}; +#define NFTA_RT_MAX (__NFTA_RT_MAX - 1) + /** * enum nft_ct_keys - nf_tables ct expression keys * diff --git a/net/netfilter/Kconfig b/net/netfilter/Kconfig index ed00ec114ea2..44410d30d461 100644 --- a/net/netfilter/Kconfig +++ b/net/netfilter/Kconfig @@ -478,6 +478,12 @@ config NFT_META This option adds the "meta" expression that you can use to match and to set packet metainformation such as the packet mark. +config NFT_RT + tristate "Netfilter nf_tables routing module" + help + This option adds the "rt" expression that you can use to match + packet routing information such as the packet nexthop. + config NFT_NUMGEN tristate "Netfilter nf_tables number generator module" help diff --git a/net/netfilter/Makefile b/net/netfilter/Makefile index 8edd791743fe..5bbf767672ec 100644 --- a/net/netfilter/Makefile +++ b/net/netfilter/Makefile @@ -84,6 +84,7 @@ obj-$(CONFIG_NF_TABLES_NETDEV) += nf_tables_netdev.o obj-$(CONFIG_NFT_COMPAT) += nft_compat.o obj-$(CONFIG_NFT_EXTHDR) += nft_exthdr.o obj-$(CONFIG_NFT_META) += nft_meta.o +obj-$(CONFIG_NFT_RT) += nft_rt.o obj-$(CONFIG_NFT_NUMGEN) += nft_numgen.o obj-$(CONFIG_NFT_CT) += nft_ct.o obj-$(CONFIG_NFT_LIMIT) += nft_limit.o 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 + * + * 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 +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +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 "); +MODULE_ALIAS_NFT_EXPR("rt"); -- cgit v1.2.3