path: root/net/openvswitch/actions.c

// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright (c) 2007-2017 Nicira, Inc.
 */

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include <linux/skbuff.h>
#include <linux/in.h>
#include <linux/ip.h>
#include <linux/openvswitch.h>
#include <linux/sctp.h>
#include <linux/tcp.h>
#include <linux/udp.h>
#include <linux/in6.h>
#include <linux/if_arp.h>
#include <linux/if_vlan.h>

#include <net/dst.h>
#include <net/ip.h>
#include <net/ipv6.h>
#include <net/ip6_fib.h>
#include <net/checksum.h>
#include <net/dsfield.h>
#include <net/mpls.h>
#include <net/sctp/checksum.h>

#include "datapath.h"
#include "flow.h"
#include "conntrack.h"
#include "vport.h"
#include "flow_netlink.h"

struct deferred_action {
	struct sk_buff *skb;
	const struct nlattr *actions;
	int actions_len;

	/* Store pkt_key clone when creating deferred action. */
	struct sw_flow_key pkt_key;
};

#define MAX_L2_LEN	(VLAN_ETH_HLEN + 3 * MPLS_HLEN)
struct ovs_frag_data {
	unsigned long dst;
	struct vport *vport;
	struct ovs_skb_cb cb;
	__be16 inner_protocol;
	u16 network_offset;	/* valid only for MPLS */
	u16 vlan_tci;
	__be16 vlan_proto;
	unsigned int l2_len;
	u8 mac_proto;
	u8 l2_data[MAX_L2_LEN];
};

static DEFINE_PER_CPU(struct ovs_frag_data, ovs_frag_data_storage);

#define DEFERRED_ACTION_FIFO_SIZE 10
#define OVS_RECURSION_LIMIT 5
#define OVS_DEFERRED_ACTION_THRESHOLD (OVS_RECURSION_LIMIT - 2)
struct action_fifo {
	int head;
	int tail;
	/* Deferred action fifo queue storage. */
	struct deferred_action fifo[DEFERRED_ACTION_FIFO_SIZE];
};

struct action_flow_keys {
	struct sw_flow_key key[OVS_DEFERRED_ACTION_THRESHOLD];
};

static struct action_fifo __percpu *action_fifos;
static struct action_flow_keys __percpu *flow_keys;
static DEFINE_PER_CPU(int, exec_actions_level);

/* Make a clone of the 'key', using the pre-allocated percpu 'flow_keys'
 * space. Return NULL if out of key spaces.
 */
static struct sw_flow_key *clone_key(const struct sw_flow_key *key_)
{
	struct action_flow_keys *keys = this_cpu_ptr(flow_keys);
	int level = this_cpu_read(exec_actions_level);
	struct sw_flow_key *key = NULL;

	if (level <= OVS_DEFERRED_ACTION_THRESHOLD) {
		key = &keys->key[level - 1];
		*key = *key_;
	}

	return key;
}

static void action_fifo_init(struct action_fifo *fifo)
{
	fifo->head = 0;
	fifo->tail = 0;
}

static bool action_fifo_is_empty(const struct action_fifo *fifo)
{
	return (fifo->head == fifo->tail);
}

static struct deferred_action *action_fifo_get(struct action_fifo *fifo)
{
	if (action_fifo_is_empty(fifo))
		return NULL;

	return &fifo->fifo[fifo->tail++];
}

static struct deferred_action *action_fifo_put(struct action_fifo *fifo)
{
	if (fifo->head >= DEFERRED_ACTION_FIFO_SIZE - 1)
		return NULL;

	return &fifo->fifo[fifo->head++];
}

/* Return true if fifo is not full */
static struct deferred_action *add_deferred_actions(struct sk_buff *skb,
				    const struct sw_flow_key *key,
				    const struct nlattr *actions,
				    const int actions_len)
{
	struct action_fifo *fifo;
	struct deferred_action *da;

	fifo = this_cpu_ptr(action_fifos);
	da = action_fifo_put(fifo);
	if (da) {
		da->skb = skb;
		da->actions = actions;
		da->actions_len = actions_len;
		da->pkt_key = *key;
	}

	return da;
}

static void invalidate_flow_key(struct sw_flow_key *key)
{
	key->mac_proto |= SW_FLOW_KEY_INVALID;
}

static bool is_flow_key_valid(const struct sw_flow_key *key)
{
	return !(key->mac_proto & SW_FLOW_KEY_INVALID);
}

static int clone_execute(struct datapath *dp, struct sk_buff *skb,
			 struct sw_flow_key *key,
			 u32 recirc_id,
			 const struct nlattr *actions, int len,
			 bool last, bool clone_flow_key);

static int do_execute_actions(struct datapath *dp, struct sk_buff *skb,
			      struct sw_flow_key *key,
			      const struct nlattr *attr, int len);

static int push_mpls(struct sk_buff *skb, struct sw_flow_key *key,
		     __be32 mpls_lse, __be16 mpls_ethertype, __u16 mac_len)
{
	int err;

	err = skb_mpls_push(skb, mpls_lse, mpls_ethertype, mac_len, !!mac_len);
	if (err)
		return err;

	if (!mac_len)
		key->mac_proto = MAC_PROTO_NONE;

	invalidate_flow_key(key);
	return 0;
}

static int pop_mpls(struct sk_buff *skb, struct sw_flow_key *key,
		    const __be16 ethertype)
{
	int err;

	err = skb_mpls_pop(skb, ethertype, skb->mac_len,
			   ovs_key_mac_proto(key) == MAC_PROTO_ETHERNET);
	if (err)
		return err;

	if (ethertype == htons(ETH_P_TEB))
		key->mac_proto = MAC_PROTO_ETHERNET;

	inval