kernel: Copy patches from kernel 4.14 to 4.19

This just copies the files from the kernel 4.14 specific folders into
the kernel 4.19 specific folder, no changes are done to the files in
this commit.

Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>

1 files changed, 334 insertions, 0 deletions

diff --git a/target/linux/generic/backport-4.19/323-v4.16-netfilter-flow-table-support-for-IPv4.patch b/target/linux/generic/backport-4.19/323-v4.16-netfilter-flow-table-support-for-IPv4.patch
new file mode 100644
index 0000000000..50d9039c12
--- /dev/null
+++ b/target/linux/generic/backport-4.19/323-v4.16-netfilter-flow-table-support-for-IPv4.patch
@@ -0,0 +1,334 @@
+From: Pablo Neira Ayuso <pablo@netfilter.org>
+Date: Sun, 7 Jan 2018 01:04:15 +0100
+Subject: [PATCH] netfilter: flow table support for IPv4
+
+This patch adds the IPv4 flow table type, that implements the datapath
+flow table to forward IPv4 traffic. Rationale is:
+
+1) Look up for the packet in the flow table, from the ingress hook.
+2) If there's a hit, decrement ttl and pass it on to the neighbour layer
+   for transmission.
+3) If there's a miss, packet is passed up to the classic forwarding
+   path.
+
+This patch also supports layer 3 source and destination NAT.
+
+Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
+---
+ create mode 100644 net/ipv4/netfilter/nf_flow_table_ipv4.c
+
+--- a/net/ipv4/netfilter/Kconfig
++++ b/net/ipv4/netfilter/Kconfig
+@@ -78,6 +78,14 @@ config NF_TABLES_ARP
+ 
+ endif # NF_TABLES
+ 
++config NF_FLOW_TABLE_IPV4
++	select NF_FLOW_TABLE
++	tristate "Netfilter flow table IPv4 module"
++	help
++	  This option adds the flow table IPv4 support.
++
++	  To compile it as a module, choose M here.
++
+ config NF_DUP_IPV4
+ 	tristate "Netfilter IPv4 packet duplication to alternate destination"
+ 	depends on !NF_CONNTRACK || NF_CONNTRACK
+--- a/net/ipv4/netfilter/Makefile
++++ b/net/ipv4/netfilter/Makefile
+@@ -43,6 +43,9 @@ obj-$(CONFIG_NFT_REDIR_IPV4) += nft_redi
+ obj-$(CONFIG_NFT_DUP_IPV4) += nft_dup_ipv4.o
+ obj-$(CONFIG_NF_TABLES_ARP) += nf_tables_arp.o
+ 
++# flow table support
++obj-$(CONFIG_NF_FLOW_TABLE_IPV4) += nf_flow_table_ipv4.o
++
+ # generic IP tables 
+ obj-$(CONFIG_IP_NF_IPTABLES) += ip_tables.o
+ 
+--- /dev/null
++++ b/net/ipv4/netfilter/nf_flow_table_ipv4.c
+@@ -0,0 +1,283 @@
++#include <linux/kernel.h>
++#include <linux/init.h>
++#include <linux/module.h>
++#include <linux/netfilter.h>
++#include <linux/rhashtable.h>
++#include <linux/ip.h>
++#include <linux/netdevice.h>
++#include <net/ip.h>
++#include <net/neighbour.h>
++#include <net/netfilter/nf_flow_table.h>
++#include <net/netfilter/nf_tables.h>
++/* For layer 4 checksum field offset. */
++#include <linux/tcp.h>
++#include <linux/udp.h>
++
++static int nf_flow_nat_ip_tcp(struct sk_buff *skb, unsigned int thoff,
++			      __be32 addr, __be32 new_addr)
++{
++	struct tcphdr *tcph;
++
++	if (!pskb_may_pull(skb, thoff + sizeof(*tcph)) ||
++	    skb_try_make_writable(skb, thoff + sizeof(*tcph)))
++		return -1;
++
++	tcph = (void *)(skb_network_header(skb) + thoff);
++	inet_proto_csum_replace4(&tcph->check, skb, addr, new_addr, true);
++
++	return 0;
++}
++
++static int nf_flow_nat_ip_udp(struct sk_buff *skb, unsigned int thoff,
++			      __be32 addr, __be32 new_addr)
++{
++	struct udphdr *udph;
++
++	if (!pskb_may_pull(skb, thoff + sizeof(*udph)) ||
++	    skb_try_make_writable(skb, thoff + sizeof(*udph)))
++		return -1;
++
++	udph = (void *)(skb_network_header(skb) + thoff);
++	if (udph->check || skb->ip_summed == CHECKSUM_PARTIAL) {
++		inet_proto_csum_replace4(&udph->check, skb, addr,
++					 new_addr, true);
++		if (!udph->check)
++			udph->check = CSUM_MANGLED_0;
++	}
++
++	return 0;
++}
++
++static int nf_flow_nat_ip_l4proto(struct sk_buff *skb, struct iphdr *iph,
++				  unsigned int thoff, __be32 addr,
++				  __be32 new_addr)
++{
++	switch (iph->protocol) {
++	case IPPROTO_TCP:
++		if (nf_flow_nat_ip_tcp(skb, thoff, addr, new_addr) < 0)
++			return NF_DROP;
++		break;
++	case IPPROTO_UDP:
++		if (nf_flow_nat_ip_udp(skb, thoff, addr, new_addr) < 0)
++			return NF_DROP;
++		break;
++	}
++
++	return 0;
++}
++
++static int nf_flow_snat_ip(const struct flow_offload *flow, struct sk_buff *skb,
++			   struct iphdr *iph, unsigned int thoff,
++			   enum flow_offload_tuple_dir dir)
++{
++	__be32 addr, new_addr;
++
++	switch (dir) {
++	case FLOW_OFFLOAD_DIR_ORIGINAL:
++		addr = iph->saddr;
++		new_addr = flow->tuplehash[FLOW_OFFLOAD_DIR_REPLY].tuple.dst_v4.s_addr;
++		iph->saddr = new_addr;
++		break;
++	case FLOW_OFFLOAD_DIR_REPLY:
++		addr = iph->daddr;
++		new_addr = flow->tuplehash[FLOW_OFFLOAD_DIR_ORIGINAL].tuple.src_v4.s_addr;
++		iph->daddr = new_addr;
++		break;
++	default:
++		return -1;
++	}
++	csum_replace4(&iph->check, addr, new_addr);
++
++	return nf_flow_nat_ip_l4proto(skb, iph, thoff, addr, new_addr);
++}
++
++static int nf_flow_dnat_ip(const struct flow_offload *flow, struct sk_buff *skb,
++			   struct iphdr *iph, unsigned int thoff,
++			   enum flow_offload_tuple_dir dir)
++{
++	__be32 addr, new_addr;
++
++	switch (dir) {
++	case FLOW_OFFLOAD_DIR_ORIGINAL:
++		addr = iph->daddr;
++		new_addr = flow->tuplehash[FLOW_OFFLOAD_DIR_REPLY].tuple.src_v4.s_addr;
++		iph->daddr = new_addr;
++		break;
++	case FLOW_OFFLOAD_DIR_REPLY:
++		addr = iph->saddr;
++		new_addr = flow->tuplehash[FLOW_OFFLOAD_DIR_ORIGINAL].tuple.dst_v4.s_addr;
++		iph->saddr = new_addr;
++		break;
++	default:
++		return -1;
++	}
++
++	return nf_flow_nat_ip_l4proto(skb, iph, thoff, addr, new_addr);
++}
++
++static int nf_flow_nat_ip(const struct flow_offload *flow, struct sk_buff *skb,
++			  enum flow_offload_tuple_dir dir)
++{
++	struct iphdr *iph = ip_hdr(skb);
++	unsigned int thoff = iph->ihl * 4;
++
++	if (flow->flags & FLOW_OFFLOAD_SNAT &&
++	    (nf_flow_snat_port(flow, skb, thoff, iph->protocol, dir) < 0 ||
++	     nf_flow_snat_ip(flow, skb, iph, thoff, dir) < 0))
++		return -1;
++	if (flow->flags & FLOW_OFFLOAD_DNAT &&
++	    (nf_flow_dnat_port(flow, skb, thoff, iph->protocol, dir) < 0 ||
++	     nf_flow_dnat_ip(flow, skb, iph, thoff, dir) < 0))
++		return -1;
++
++	return 0;
++}
++
++static bool ip_has_options(unsigned int thoff)
++{
++	return thoff != sizeof(struct iphdr);
++}
++
++static int nf_flow_tuple_ip(struct sk_buff *skb, const struct net_device *dev,
++			    struct flow_offload_tuple *tuple)
++{
++	struct flow_ports *ports;
++	unsigned int thoff;
++	struct iphdr *iph;
++
++	if (!pskb_may_pull(skb, sizeof(*iph)))
++		return -1;
++
++	iph = ip_hdr(skb);
++	thoff = iph->ihl * 4;
++
++	if (ip_is_fragment(iph) ||
++	    unlikely(ip_has_options(thoff)))
++		return -1;
++
++	if (iph->protocol != IPPROTO_TCP &&
++	    iph->protocol != IPPROTO_UDP)
++		return -1;
++
++	thoff = iph->ihl * 4;
++	if (!pskb_may_pull(skb, thoff + sizeof(*ports)))
++		return -1;
++
++	ports = (struct flow_ports *)(skb_network_header(skb) + thoff);
++
++	tuple->src_v4.s_addr	= iph->saddr;
++	tuple->dst_v4.s_addr	= iph->daddr;
++	tuple->src_port		= ports->source;
++	tuple->dst_port		= ports->dest;
++	tuple->l3proto		= AF_INET;
++	tuple->l4proto		= iph->protocol;
++	tuple->iifidx		= dev->ifindex;
++
++	return 0;
++}
++
++/* Based on ip_exceeds_mtu(). */
++static bool __nf_flow_exceeds_mtu(const struct sk_buff *skb, unsigned int mtu)
++{
++	if (skb->len <= mtu)
++		return false;
++
++	if ((ip_hdr(skb)->frag_off & htons(IP_DF)) == 0)
++		return false;
++
++	if (skb_is_gso(skb) && skb_gso_validate_mtu(skb, mtu))
++		return false;
++
++	return true;
++}
++
++static bool nf_flow_exceeds_mtu(struct sk_buff *skb, const struct rtable *rt)
++{
++	u32 mtu;
++
++	mtu = ip_dst_mtu_maybe_forward(&rt->dst, true);
++	if (__nf_flow_exceeds_mtu(skb, mtu))
++		return true;
++
++	return false;
++}
++
++static unsigned int
++nf_flow_offload_ip_hook(void *priv, struct sk_buff *skb,
++			const struct nf_hook_state *state)
++{
++	struct flow_offload_tuple_rhash *tuplehash;
++	struct nf_flowtable *flow_table = priv;
++	struct flow_offload_tuple tuple = {};
++	enum flow_offload_tuple_dir dir;
++	struct flow_offload *flow;
++	struct net_device *outdev;
++	const struct rtable *rt;
++	struct iphdr *iph;
++	__be32 nexthop;
++
++	if (skb->protocol != htons(ETH_P_IP))
++		return NF_ACCEPT;
++
++	if (nf_flow_tuple_ip(skb, state->in, &tuple) < 0)
++		return NF_ACCEPT;
++
++	tuplehash = flow_offload_lookup(flow_table, &tuple);
++	if (tuplehash == NULL)
++		return NF_ACCEPT;
++
++	outdev = dev_get_by_index_rcu(state->net, tuplehash->tuple.oifidx);
++	if (!outdev)
++		return NF_ACCEPT;
++
++	dir = tuplehash->tuple.dir;
++	flow = container_of(tuplehash, struct flow_offload, tuplehash[dir]);
++
++	rt = (const struct rtable *)flow->tuplehash[dir].tuple.dst_cache;
++	if (unlikely(nf_flow_exceeds_mtu(skb, rt)))
++		return NF_ACCEPT;
++
++	if (skb_try_make_writable(skb, sizeof(*iph)))
++		return NF_DROP;
++
++	if (flow->flags & (FLOW_OFFLOAD_SNAT | FLOW_OFFLOAD_DNAT) &&
++	    nf_flow_nat_ip(flow, skb, dir) < 0)
++		return NF_DROP;
++
++	flow->timeout = (u32)jiffies + NF_FLOW_TIMEOUT;
++	iph = ip_hdr(skb);
++	ip_decrease_ttl(iph);
++
++	skb->dev = outdev;
++	nexthop = rt_nexthop(rt, flow->tuplehash[!dir].tuple.src_v4.s_addr);
++	neigh_xmit(NEIGH_ARP_TABLE, outdev, &nexthop, skb);
++
++	return NF_STOLEN;
++}
++
++static struct nf_flowtable_type flowtable_ipv4 = {
++	.family		= NFPROTO_IPV4,
++	.params		= &nf_flow_offload_rhash_params,
++	.gc		= nf_flow_offload_work_gc,
++	.hook		= nf_flow_offload_ip_hook,
++	.owner		= THIS_MODULE,
++};
++
++static int __init nf_flow_ipv4_module_init(void)
++{
++	nft_register_flowtable_type(&flowtable_ipv4);
++
++	return 0;
++}
++
++static void __exit nf_flow_ipv4_module_exit(void)
++{
++	nft_unregister_flowtable_type(&flowtable_ipv4);
++}
++
++module_init(nf_flow_ipv4_module_init);
++module_exit(nf_flow_ipv4_module_exit);
++
++MODULE_LICENSE("GPL");
++MODULE_AUTHOR("Pablo Neira Ayuso <pablo@netfilter.org>");
++MODULE_ALIAS_NF_FLOWTABLE(AF_INET);