diff options
Diffstat (limited to 'net/ipv4')
| -rw-r--r-- | net/ipv4/netfilter/Kconfig | 12 | ||||
| -rw-r--r-- | net/ipv4/netfilter/Makefile | 3 | ||||
| -rw-r--r-- | net/ipv4/netfilter/nf_conntrack_l3proto_ipv4.c | 2 | ||||
| -rw-r--r-- | net/ipv4/netfilter/nf_conntrack_proto_icmp.c | 4 | ||||
| -rw-r--r-- | net/ipv4/netfilter/nf_defrag_ipv4.c | 17 | ||||
| -rw-r--r-- | net/ipv4/netfilter/nf_dup_ipv4.c | 120 | ||||
| -rw-r--r-- | net/ipv4/netfilter/nft_dup_ipv4.c | 110 |
7 files changed, 259 insertions, 9 deletions
diff --git a/net/ipv4/netfilter/Kconfig b/net/ipv4/netfilter/Kconfig index 2199a5db25e6..690d27d3f2f9 100644 --- a/net/ipv4/netfilter/Kconfig +++ b/net/ipv4/netfilter/Kconfig @@ -58,6 +58,12 @@ config NFT_REJECT_IPV4 default NFT_REJECT tristate +config NFT_DUP_IPV4 + tristate "IPv4 nf_tables packet duplication support" + select NF_DUP_IPV4 + help + This module enables IPv4 packet duplication support for nf_tables. + endif # NF_TABLES_IPV4 config NF_TABLES_ARP @@ -67,6 +73,12 @@ config NF_TABLES_ARP endif # NF_TABLES +config NF_DUP_IPV4 + tristate "Netfilter IPv4 packet duplication to alternate destination" + help + This option enables the nf_dup_ipv4 core, which duplicates an IPv4 + packet to be rerouted to another destination. + config NF_LOG_ARP tristate "ARP packet logging" default m if NETFILTER_ADVANCED=n diff --git a/net/ipv4/netfilter/Makefile b/net/ipv4/netfilter/Makefile index 7fe6c703528f..87b073da14c9 100644 --- a/net/ipv4/netfilter/Makefile +++ b/net/ipv4/netfilter/Makefile @@ -41,6 +41,7 @@ obj-$(CONFIG_NFT_CHAIN_NAT_IPV4) += nft_chain_nat_ipv4.o obj-$(CONFIG_NFT_REJECT_IPV4) += nft_reject_ipv4.o obj-$(CONFIG_NFT_MASQ_IPV4) += nft_masq_ipv4.o obj-$(CONFIG_NFT_REDIR_IPV4) += nft_redir_ipv4.o +obj-$(CONFIG_NFT_DUP_IPV4) += nft_dup_ipv4.o obj-$(CONFIG_NF_TABLES_ARP) += nf_tables_arp.o # generic IP tables @@ -70,3 +71,5 @@ obj-$(CONFIG_IP_NF_ARP_MANGLE) += arpt_mangle.o # just filtering instance of ARP tables for now obj-$(CONFIG_IP_NF_ARPFILTER) += arptable_filter.o + +obj-$(CONFIG_NF_DUP_IPV4) += nf_dup_ipv4.o diff --git a/net/ipv4/netfilter/nf_conntrack_l3proto_ipv4.c b/net/ipv4/netfilter/nf_conntrack_l3proto_ipv4.c index 30ad9554b5e9..8a2caaf3940b 100644 --- a/net/ipv4/netfilter/nf_conntrack_l3proto_ipv4.c +++ b/net/ipv4/netfilter/nf_conntrack_l3proto_ipv4.c @@ -280,7 +280,7 @@ getorigdst(struct sock *sk, int optval, void __user *user, int *len) return -EINVAL; } - h = nf_conntrack_find_get(sock_net(sk), NF_CT_DEFAULT_ZONE, &tuple); + h = nf_conntrack_find_get(sock_net(sk), &nf_ct_zone_dflt, &tuple); if (h) { struct sockaddr_in sin; struct nf_conn *ct = nf_ct_tuplehash_to_ctrack(h); diff --git a/net/ipv4/netfilter/nf_conntrack_proto_icmp.c b/net/ipv4/netfilter/nf_conntrack_proto_icmp.c index 80d5554b9a88..cdde3ec496e9 100644 --- a/net/ipv4/netfilter/nf_conntrack_proto_icmp.c +++ b/net/ipv4/netfilter/nf_conntrack_proto_icmp.c @@ -134,9 +134,11 @@ icmp_error_message(struct net *net, struct nf_conn *tmpl, struct sk_buff *skb, struct nf_conntrack_tuple innertuple, origtuple; const struct nf_conntrack_l4proto *innerproto; const struct nf_conntrack_tuple_hash *h; - u16 zone = tmpl ? nf_ct_zone(tmpl) : NF_CT_DEFAULT_ZONE; + const struct nf_conntrack_zone *zone; + struct nf_conntrack_zone tmp; NF_CT_ASSERT(skb->nfct == NULL); + zone = nf_ct_zone_tmpl(tmpl, skb, &tmp); /* Are they talking about one of our connections? */ if (!nf_ct_get_tuplepr(skb, diff --git a/net/ipv4/netfilter/nf_defrag_ipv4.c b/net/ipv4/netfilter/nf_defrag_ipv4.c index b69e82bda215..9306ec4fab41 100644 --- a/net/ipv4/netfilter/nf_defrag_ipv4.c +++ b/net/ipv4/netfilter/nf_defrag_ipv4.c @@ -43,19 +43,22 @@ static int nf_ct_ipv4_gather_frags(struct sk_buff *skb, u_int32_t user) static enum ip_defrag_users nf_ct_defrag_user(unsigned int hooknum, struct sk_buff *skb) { - u16 zone = NF_CT_DEFAULT_ZONE; - + u16 zone_id = NF_CT_DEFAULT_ZONE_ID; #if IS_ENABLED(CONFIG_NF_CONNTRACK) - if (skb->nfct) - zone = nf_ct_zone((struct nf_conn *)skb->nfct); + if (skb->nfct) { + enum ip_conntrack_info ctinfo; + const struct nf_conn *ct = nf_ct_get(skb, &ctinfo); + + zone_id = nf_ct_zone_id(nf_ct_zone(ct), CTINFO2DIR(ctinfo)); + } #endif if (nf_bridge_in_prerouting(skb)) - return IP_DEFRAG_CONNTRACK_BRIDGE_IN + zone; + return IP_DEFRAG_CONNTRACK_BRIDGE_IN + zone_id; if (hooknum == NF_INET_PRE_ROUTING) - return IP_DEFRAG_CONNTRACK_IN + zone; + return IP_DEFRAG_CONNTRACK_IN + zone_id; else - return IP_DEFRAG_CONNTRACK_OUT + zone; + return IP_DEFRAG_CONNTRACK_OUT + zone_id; } static unsigned int ipv4_conntrack_defrag(const struct nf_hook_ops *ops, diff --git a/net/ipv4/netfilter/nf_dup_ipv4.c b/net/ipv4/netfilter/nf_dup_ipv4.c new file mode 100644 index 000000000000..b5bb37564b0e --- /dev/null +++ b/net/ipv4/netfilter/nf_dup_ipv4.c @@ -0,0 +1,120 @@ +/* + * (C) 2007 by Sebastian Claßen <sebastian.classen@freenet.ag> + * (C) 2007-2010 by Jan Engelhardt <jengelh@medozas.de> + * + * Extracted from xt_TEE.c + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 or later, as + * published by the Free Software Foundation. + */ +#include <linux/ip.h> +#include <linux/module.h> +#include <linux/percpu.h> +#include <linux/route.h> +#include <linux/skbuff.h> +#include <net/checksum.h> +#include <net/icmp.h> +#include <net/ip.h> +#include <net/route.h> +#include <net/netfilter/ipv4/nf_dup_ipv4.h> +#if IS_ENABLED(CONFIG_NF_CONNTRACK) +#include <net/netfilter/nf_conntrack.h> +#endif + +static struct net *pick_net(struct sk_buff *skb) +{ +#ifdef CONFIG_NET_NS + const struct dst_entry *dst; + + if (skb->dev != NULL) + return dev_net(skb->dev); + dst = skb_dst(skb); + if (dst != NULL && dst->dev != NULL) + return dev_net(dst->dev); +#endif + return &init_net; +} + +static bool nf_dup_ipv4_route(struct sk_buff *skb, const struct in_addr *gw, + int oif) +{ + const struct iphdr *iph = ip_hdr(skb); + struct net *net = pick_net(skb); + struct rtable *rt; + struct flowi4 fl4; + + memset(&fl4, 0, sizeof(fl4)); + if (oif != -1) + fl4.flowi4_oif = oif; + + fl4.daddr = gw->s_addr; + fl4.flowi4_tos = RT_TOS(iph->tos); + fl4.flowi4_scope = RT_SCOPE_UNIVERSE; + fl4.flowi4_flags = FLOWI_FLAG_KNOWN_NH; + rt = ip_route_output_key(net, &fl4); + if (IS_ERR(rt)) + return false; + + skb_dst_drop(skb); + skb_dst_set(skb, &rt->dst); + skb->dev = rt->dst.dev; + skb->protocol = htons(ETH_P_IP); + + return true; +} + +void nf_dup_ipv4(struct sk_buff *skb, unsigned int hooknum, + const struct in_addr *gw, int oif) +{ + struct iphdr *iph; + + if (this_cpu_read(nf_skb_duplicated)) + return; + /* + * Copy the skb, and route the copy. Will later return %XT_CONTINUE for + * the original skb, which should continue on its way as if nothing has + * happened. The copy should be independently delivered to the gateway. + */ + skb = pskb_copy(skb, GFP_ATOMIC); + if (skb == NULL) + return; + +#if IS_ENABLED(CONFIG_NF_CONNTRACK) + /* Avoid counting cloned packets towards the original connection. */ + nf_conntrack_put(skb->nfct); + skb->nfct = &nf_ct_untracked_get()->ct_general; + skb->nfctinfo = IP_CT_NEW; + nf_conntrack_get(skb->nfct); +#endif + /* + * If we are in PREROUTING/INPUT, the checksum must be recalculated + * since the length could have changed as a result of defragmentation. + * + * We also decrease the TTL to mitigate potential loops between two + * hosts. + * + * Set %IP_DF so that the original source is notified of a potentially + * decreased MTU on the clone route. IPv6 does this too. + */ + iph = ip_hdr(skb); + iph->frag_off |= htons(IP_DF); + if (hooknum == NF_INET_PRE_ROUTING || + hooknum == NF_INET_LOCAL_IN) + --iph->ttl; + ip_send_check(iph); + + if (nf_dup_ipv4_route(skb, gw, oif)) { + __this_cpu_write(nf_skb_duplicated, true); + ip_local_out(skb); + __this_cpu_write(nf_skb_duplicated, false); + } else { + kfree_skb(skb); + } +} +EXPORT_SYMBOL_GPL(nf_dup_ipv4); + +MODULE_AUTHOR("Sebastian Claßen <sebastian.classen@freenet.ag>"); +MODULE_AUTHOR("Jan Engelhardt <jengelh@medozas.de>"); +MODULE_DESCRIPTION("nf_dup_ipv4: Duplicate IPv4 packet"); +MODULE_LICENSE("GPL"); diff --git a/net/ipv4/netfilter/nft_dup_ipv4.c b/net/ipv4/netfilter/nft_dup_ipv4.c new file mode 100644 index 000000000000..25419fbddcb6 --- /dev/null +++ b/net/ipv4/netfilter/nft_dup_ipv4.c @@ -0,0 +1,110 @@ +/* + * Copyright (c) 2015 Pablo Neira Ayuso <pablo@netfilter.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. + */ + +#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/netfilter/ipv4/nf_dup_ipv4.h> + +struct nft_dup_ipv4 { + enum nft_registers sreg_addr:8; + enum nft_registers sreg_dev:8; +}; + +static void nft_dup_ipv4_eval(const struct nft_expr *expr, + struct nft_regs *regs, + const struct nft_pktinfo *pkt) +{ + struct nft_dup_ipv4 *priv = nft_expr_priv(expr); + struct in_addr gw = { + .s_addr = regs->data[priv->sreg_addr], + }; + int oif = regs->data[priv->sreg_dev]; + + nf_dup_ipv4(pkt->skb, pkt->ops->hooknum, &gw, oif); +} + +static int nft_dup_ipv4_init(const struct nft_ctx *ctx, + const struct nft_expr *expr, + const struct nlattr * const tb[]) +{ + struct nft_dup_ipv4 *priv = nft_expr_priv(expr); + int err; + + if (tb[NFTA_DUP_SREG_ADDR] == NULL) + return -EINVAL; + + priv->sreg_addr = nft_parse_register(tb[NFTA_DUP_SREG_ADDR]); + err = nft_validate_register_load(priv->sreg_addr, sizeof(struct in_addr)); + if (err < 0) + return err; + + if (tb[NFTA_DUP_SREG_DEV] != NULL) { + priv->sreg_dev = nft_parse_register(tb[NFTA_DUP_SREG_DEV]); + return nft_validate_register_load(priv->sreg_dev, sizeof(int)); + } + return 0; +} + +static int nft_dup_ipv4_dump(struct sk_buff *skb, const struct nft_expr *expr) +{ + struct nft_dup_ipv4 *priv = nft_expr_priv(expr); + + if (nft_dump_register(skb, NFTA_DUP_SREG_ADDR, priv->sreg_addr) || + nft_dump_register(skb, NFTA_DUP_SREG_DEV, priv->sreg_dev)) + goto nla_put_failure; + + return 0; + +nla_put_failure: + return -1; +} + +static struct nft_expr_type nft_dup_ipv4_type; +static const struct nft_expr_ops nft_dup_ipv4_ops = { + .type = &nft_dup_ipv4_type, + .size = NFT_EXPR_SIZE(sizeof(struct nft_dup_ipv4)), + .eval = nft_dup_ipv4_eval, + .init = nft_dup_ipv4_init, + .dump = nft_dup_ipv4_dump, +}; + +static const struct nla_policy nft_dup_ipv4_policy[NFTA_DUP_MAX + 1] = { + [NFTA_DUP_SREG_ADDR] = { .type = NLA_U32 }, + [NFTA_DUP_SREG_DEV] = { .type = NLA_U32 }, +}; + +static struct nft_expr_type nft_dup_ipv4_type __read_mostly = { + .family = NFPROTO_IPV4, + .name = "dup", + .ops = &nft_dup_ipv4_ops, + .policy = nft_dup_ipv4_policy, + .maxattr = NFTA_DUP_MAX, + .owner = THIS_MODULE, +}; + +static int __init nft_dup_ipv4_module_init(void) +{ + return nft_register_expr(&nft_dup_ipv4_type); +} + +static void __exit nft_dup_ipv4_module_exit(void) +{ + nft_unregister_expr(&nft_dup_ipv4_type); +} + +module_init(nft_dup_ipv4_module_init); +module_exit(nft_dup_ipv4_module_exit); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Pablo Neira Ayuso <pablo@netfilter.org>"); +MODULE_ALIAS_NFT_AF_EXPR(AF_INET, "dup"); |