[deliverable/linux.git] / net / openvswitch / actions.c

/*
 * Copyright (c) 2007-2012 Nicira, Inc.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of version 2 of the GNU General Public
 * License as published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
 * General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
 * 02110-1301, USA
 */

#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/tcp.h>
#include <linux/udp.h>
#include <linux/in6.h>
#include <linux/if_arp.h>
#include <linux/if_vlan.h>
#include <net/ip.h>
#include <net/ipv6.h>
#include <net/checksum.h>
#include <net/dsfield.h>

#include "datapath.h"
#include "vport.h"

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

static int make_writable(struct sk_buff *skb, int write_len)
{
	if (!skb_cloned(skb) || skb_clone_writable(skb, write_len))
		return 0;

	return pskb_expand_head(skb, 0, 0, GFP_ATOMIC);
}

/* remove VLAN header from packet and update csum accordingly. */
static int __pop_vlan_tci(struct sk_buff *skb, __be16 *current_tci)
{
	struct vlan_hdr *vhdr;
	int err;

	err = make_writable(skb, VLAN_ETH_HLEN);
	if (unlikely(err))
		return err;

	if (skb->ip_summed == CHECKSUM_COMPLETE)
		skb->csum = csum_sub(skb->csum, csum_partial(skb->data
					+ (2 * ETH_ALEN), VLAN_HLEN, 0));

	vhdr = (struct vlan_hdr *)(skb->data + ETH_HLEN);
	*current_tci = vhdr->h_vlan_TCI;

	memmove(skb->data + VLAN_HLEN, skb->data, 2 * ETH_ALEN);
	__skb_pull(skb, VLAN_HLEN);

	vlan_set_encap_proto(skb, vhdr);
	skb->mac_header += VLAN_HLEN;
	skb_reset_mac_len(skb);

	return 0;
}

static int pop_vlan(struct sk_buff *skb)
{
	__be16 tci;
	int err;

	if (likely(vlan_tx_tag_present(skb))) {
		skb->vlan_tci = 0;
	} else {
		if (unlikely(skb->protocol != htons(ETH_P_8021Q) ||
			     skb->len < VLAN_ETH_HLEN))
			return 0;

		err = __pop_vlan_tci(skb, &tci);
		if (err)
			return err;
	}
	/* move next vlan tag to hw accel tag */
	if (likely(skb->protocol != htons(ETH_P_8021Q) ||
		   skb->len < VLAN_ETH_HLEN))
		return 0;

	err = __pop_vlan_tci(skb, &tci);
	if (unlikely(err))
		return err;

	__vlan_hwaccel_put_tag(skb, htons(ETH_P_8021Q), ntohs(tci));
	return 0;
}

static int push_vlan(struct sk_buff *skb, const struct ovs_action_push_vlan *vlan)
{
	if (unlikely(vlan_tx_tag_present(skb))) {
		u16 current_tag;

		/* push down current VLAN tag */
		current_tag = vlan_tx_tag_get(skb);

		if (!__vlan_put_tag(skb, skb->vlan_proto, current_tag))
			return -ENOMEM;

		if (skb->ip_summed == CHECKSUM_COMPLETE)
			skb->csum = csum_add(skb->csum, csum_partial(skb->data
					+ (2 * ETH_ALEN), VLAN_HLEN, 0));

	}
	__vlan_hwaccel_put_tag(skb, vlan->vlan_tpid, ntohs(vlan->vlan_tci) & ~VLAN_TAG_PRESENT);
	return 0;
}

static int set_eth_addr(struct sk_buff *skb,
			const struct ovs_key_ethernet *eth_key)
{
	int err;
	err = make_writable(skb, ETH_HLEN);
	if (unlikely(err))
		return err;

	skb_postpull_rcsum(skb, eth_hdr(skb), ETH_ALEN * 2);

	memcpy(eth_hdr(skb)->h_source, eth_key->eth_src, ETH_ALEN);
	memcpy(eth_hdr(skb)->h_dest, eth_key->eth_dst, ETH_ALEN);

	ovs_skb_postpush_rcsum(skb, eth_hdr(skb), ETH_ALEN * 2);

	return 0;
}

static void set_ip_addr(struct sk_buff *skb, struct iphdr *nh,
				__be32 *addr, __be32 new_addr)
{
	int transport_len = skb->len - skb_transport_offset(skb);

	if (nh->protocol == IPPROTO_TCP) {
		if (likely(transport_len >= sizeof(struct tcphdr)))
			inet_proto_csum_replace4(&tcp_hdr(skb)->check, skb,
						 *addr, new_addr, 1);
	} else if (nh->protocol == IPPROTO_UDP) {
		if (likely(transport_len >= sizeof(struct udphdr))) {
			struct udphdr *uh = udp_hdr(skb);

			if (uh->check || skb->ip_summed == CHECKSUM_PARTIAL) {
				inet_proto_csum_replace4(&uh->check, skb,
							 *addr, new_addr, 1);
				if (!uh->check)
					uh->check = CSUM_MANGLED_0;
			}
		}
	}

	csum_replace4(&nh->check, *addr, new_addr);
	skb->rxhash = 0;
	*addr = new_addr;
}

static void update_ipv6_checksum(struct sk_buff *skb, u8 l4_proto,
				 __be32 addr[4], const __be32 new_addr[4])
{
	int transport_len = skb->len - skb_transport_offset(skb);

	if (l4_proto == IPPROTO_TCP) {
		if (likely(transport_len >= sizeof(struct tcphdr)))
			inet_proto_csum_replace16(&tcp_hdr(skb)->check, skb,
						  addr, new_addr, 1);
	} else if (l4_proto == IPPROTO_UDP) {
		if (likely(transport_len >= sizeof(struct udphdr))) {
			struct udphdr *uh = udp_hdr(skb);

			if (uh->check || skb->ip_summed == CHECKSUM_PARTIAL) {
				inet_proto_csum_replace16(&uh->check, skb,
							  addr, new_addr, 1);
				if (!uh->check)
					uh->check = CSUM_MANGLED_0;
			}
		}
	}
}

static void set_ipv6_addr(struct sk_buff *skb, u8 l4_proto,
			  __be32 addr[4], const __be32 new_addr[4],
			  bool recalculate_csum)
{
	if (recalculate_csum)
		update_ipv6_checksum(skb, l4_proto, addr, new_addr);

	skb->rxhash = 0;
	memcpy(addr, new_addr, sizeof(__be32[4]));
}

static void set_ipv6_tc(struct ipv6hdr *nh, u8 tc)
{
	nh->priority = tc >> 4;
	nh->flow_lbl[0] = (nh->flow_lbl[0] & 0x0F) | ((tc & 0x0F) << 4);
}

static void set_ipv6_fl(struct ipv6hdr *nh, u32 fl)
{
	nh->flow_lbl[0] = (nh->flow_lbl[0] & 0xF0) | (fl & 0x000F0000) >> 16;
	nh->flow_lbl[1] = (fl & 0x0000FF00) >> 8;
	nh->flow_lbl[2] = fl & 0x000000FF;
}

static void set_ip_ttl(struct sk_buff *skb, struct iphdr *nh, u8 new_ttl)
{
	csum_replace2(&nh->check, htons(nh->ttl << 8), htons(new_ttl << 8));
	nh->ttl = new_ttl;
}

static int set_ipv4(struct sk_buff *skb, const struct ovs_key_ipv4 *ipv4_key)
{
	struct iphdr *nh;
	int err;

	err = make_writable(skb, skb_network_offset(skb) +
				 sizeof(struct iphdr));
	if (unlikely(err))
		return err;

	nh = ip_hdr(skb);

	if (ipv4_key->ipv4_src != nh->saddr)
		set_ip_addr(skb, nh, &nh->saddr, ipv4_key->ipv4_src);

	if (ipv4_key->ipv4_dst != nh->daddr)
		set_ip_addr(skb, nh, &nh->daddr, ipv4_key->ipv4_dst);

	if (ipv4_key->ipv4_tos != nh->tos)
		ipv4_change_dsfield(nh, 0, ipv4_key->ipv4_tos);

	if (ipv4_key->ipv4_ttl != nh->ttl)
		set_ip_ttl(skb, nh, ipv4_key->ipv4_ttl);

	return 0;
}

static int set_ipv6(struct sk_buff *skb, const struct ovs_key_ipv6 *ipv6_key)
{
	struct ipv6hdr *nh;
	int err;
	__be32 *saddr;
	__be32 *daddr;

	err = make_writable(skb, skb_network_offset(skb) +
			    sizeof(struct ipv6hdr));
	if (unlikely(err))
		return err;

	nh = ipv6_hdr(skb);
	saddr = (__be32 *)&nh->saddr;
	daddr = (__be32 *)&nh->daddr;

	if (memcmp(ipv6_key->ipv6_src, saddr, sizeof(ipv6_key->ipv6_src)))
		set_ipv6_addr(skb, ipv6_key->ipv6_proto, saddr,
			      ipv6_key->ipv6_src, true);

	if (memcmp(ipv6_key->ipv6_dst, daddr, sizeof(ipv6_key->ipv6_dst))) {
		unsigned int offset = 0;
		int flags = IP6_FH_F_SKIP_RH;
		bool recalc_csum = true;

		if (ipv6_ext_hdr(nh->nexthdr))
			recalc_csum = ipv6_find_hdr(skb, &offset,
						    NEXTHDR_ROUTING, NULL,
						    &flags) != NEXTHDR_ROUTING;

		set_ipv6_addr(skb, ipv6_key->ipv6_proto, daddr,
			      ipv6_key->ipv6_dst, recalc_csum);
	}

	set_ipv6_tc(nh, ipv6_key->ipv6_tclass);
	set_ipv6_fl(nh, ntohl(ipv6_key->ipv6_label));
	nh->hop_limit = ipv6_key->ipv6_hlimit;

	return 0;
}

/* Must follow make_writable() since that can move the skb data. */
static void set_tp_port(struct sk_buff *skb, __be16 *port,
			 __be16 new_port, __sum16 *check)
{
	inet_proto_csum_replace2(check, skb, *port, new_port, 0);
	*port = new_port;
	skb->rxhash = 0;
}

static void set_udp_port(struct sk_buff *skb, __be16 *port, __be16 new_port)
{
	struct udphdr *uh = udp_hdr(skb);

	if (uh->check && skb->ip_summed != CHECKSUM_PARTIAL) {
		set_tp_port(skb, port, new_port, &uh->check);

		if (!uh->check)
			uh->check = CSUM_MANGLED_0;
	} else {
		*port = new_port;
		skb->rxhash = 0;
	}
}

static int set_udp(struct sk_buff *skb, const struct ovs_key_udp *udp_port_key)
{
	struct udphdr *uh;
	int err;

	err = make_writable(skb, skb_transport_offset(skb) +
				 sizeof(struct udphdr));
	if (unlikely(err))
		return err;

	uh = udp_hdr(skb);
	if (udp_port_key->udp_src != uh->source)
		set_udp_port(skb, &uh->source, udp_port_key->udp_src);

	if (udp_port_key->udp_dst != uh->dest)
		set_udp_port(skb, &uh->dest, udp_port_key->udp_dst);

	return 0;
}

static int set_tcp(struct sk_buff *skb, const struct ovs_key_tcp *tcp_port_key)
{
	struct tcphdr *th;
	int err;

	err = make_writable(skb, skb_transport_offset(skb) +
				 sizeof(struct tcphdr));
	if (unlikely(err))
		return err;

	th = tcp_hdr(skb);
	if (tcp_port_key->tcp_src != th->source)
		set_tp_port(skb, &th->source, tcp_port_key->tcp_src, &th->check);

	if (tcp_port_key->tcp_dst != th->dest)
		set_tp_port(skb, &th->dest, tcp_port_key->tcp_dst, &th->check);

	return 0;
}

static int do_output(struct datapath *dp, struct sk_buff *skb, int out_port)
{
	struct vport *vport;

	if (unlikely(!skb))
		return -ENOMEM;

	vport = ovs_vport_rcu(dp, out_port);
	if (unlikely(!vport)) {
		kfree_skb(skb);
		return -ENODEV;
	}

	ovs_vport_send(vport, skb);
	return 0;
}

static int output_userspace(struct datapath *dp, struct sk_buff *skb,
			    const struct nlattr *attr)
{
	struct dp_upcall_info upcall;
	const struct nlattr *a;
	int rem;

	upcall.cmd = OVS_PACKET_CMD_ACTION;
	upcall.key = &OVS_CB(skb)->flow->key;
	upcall.userdata = NULL;
	upcall.portid = 0;

	for (a = nla_data(attr), rem = nla_len(attr); rem > 0;
		 a = nla_next(a, &rem)) {
		switch (nla_type(a)) {
		case OVS_USERSPACE_ATTR_USERDATA:
			upcall.userdata = a;
			break;

		case OVS_USERSPACE_ATTR_PID:
			upcall.portid = nla_get_u32(a);
			break;
		}
	}

	return ovs_dp_upcall(dp, skb, &upcall);
}

static int sample(struct datapath *dp, struct sk_buff *skb,
		  const struct nlattr *attr)
{
	const struct nlattr *acts_list = NULL;
	const struct nlattr *a;
	int rem;

	for (a = nla_data(attr), rem = nla_len(attr); rem > 0;
		 a = nla_next(a, &rem)) {
		switch (nla_type(a)) {
		case OVS_SAMPLE_ATTR_PROBABILITY:
			if (net_random() >= nla_get_u32(a))
				return 0;
			break;

		case OVS_SAMPLE_ATTR_ACTIONS:
			acts_list = a;
			break;
		}
	}

	return do_execute_actions(dp, skb, nla_data(acts_list),
						 nla_len(acts_list), true);
}

static int execute_set_action(struct sk_buff *skb,
				 const struct nlattr *nested_attr)
{
	int err = 0;

	switch (nla_type(nested_attr)) {
	case OVS_KEY_ATTR_PRIORITY:
		skb->priority = nla_get_u32(nested_attr);
		break;

	case OVS_KEY_ATTR_SKB_MARK:
		skb->mark = nla_get_u32(nested_attr);
		break;

	case OVS_KEY_ATTR_ETHERNET:
		err = set_eth_addr(skb, nla_data(nested_attr));
		break;

	case OVS_KEY_ATTR_IPV4:
		err = set_ipv4(skb, nla_data(nested_attr));
		break;

	case OVS_KEY_ATTR_IPV6:
		err = set_ipv6(skb, nla_data(nested_attr));
		break;

	case OVS_KEY_ATTR_TCP:
		err = set_tcp(skb, nla_data(nested_attr));
		break;

	case OVS_KEY_ATTR_UDP:
		err = set_udp(skb, nla_data(nested_attr));
		break;
	}

	return err;
}

/* Execute a list of actions against 'skb'. */
static int do_execute_actions(struct datapath *dp, struct sk_buff *skb,
			const struct nlattr *attr, int len, bool keep_skb)
{
	/* Every output action needs a separate clone of 'skb', but the common
	 * case is just a single output action, so that doing a clone and
	 * then freeing the original skbuff is wasteful.  So the following code
	 * is slightly obscure just to avoid that. */
	int prev_port = -1;
	const struct nlattr *a;
	int rem;

	for (a = attr, rem = len; rem > 0;
	     a = nla_next(a, &rem)) {
		int err = 0;

		if (prev_port != -1) {
			do_output(dp, skb_clone(skb, GFP_ATOMIC), prev_port);
			prev_port = -1;
		}

		switch (nla_type(a)) {
		case OVS_ACTION_ATTR_OUTPUT:
			prev_port = nla_get_u32(a);
			break;

		case OVS_ACTION_ATTR_USERSPACE:
			output_userspace(dp, skb, a);
			break;

		case OVS_ACTION_ATTR_PUSH_VLAN:
			err = push_vlan(skb, nla_data(a));
			if (unlikely(err)) /* skb already freed. */
				return err;
			break;

		case OVS_ACTION_ATTR_POP_VLAN:
			err = pop_vlan(skb);
			break;

		case OVS_ACTION_ATTR_SET:
			err = execute_set_action(skb, nla_data(a));
			break;

		case OVS_ACTION_ATTR_SAMPLE:
			err = sample(dp, skb, a);
			break;
		}

		if (unlikely(err)) {
			kfree_skb(skb);
			return err;
		}
	}

	if (prev_port != -1) {
		if (keep_skb)
			skb = skb_clone(skb, GFP_ATOMIC);

		do_output(dp, skb, prev_port);
	} else if (!keep_skb)
		consume_skb(skb);

	return 0;
}

/* Execute a list of actions against 'skb'. */
int ovs_execute_actions(struct datapath *dp, struct sk_buff *skb)
{
	struct sw_flow_actions *acts = rcu_dereference(OVS_CB(skb)->flow->sf_acts);

	return do_execute_actions(dp, skb, acts->actions,
					 acts->actions_len, false);
}
Commit	Line	Data
ccb1352e	1	/*
caf2ee14	2	* Copyright (c) 2007-2012 Nicira, Inc.
ccb1352e JG	3	*
	4	* This program is free software; you can redistribute it and/or
	5	* modify it under the terms of version 2 of the GNU General Public
	6	* License as published by the Free Software Foundation.
	7	*
	8	* This program is distributed in the hope that it will be useful, but
	9	* WITHOUT ANY WARRANTY; without even the implied warranty of
	10	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	11	* General Public License for more details.
	12	*
	13	* You should have received a copy of the GNU General Public License
	14	* along with this program; if not, write to the Free Software
	15	* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
	16	* 02110-1301, USA
	17	*/
	18
	19	#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
	20
	21	#include <linux/skbuff.h>
	22	#include <linux/in.h>
	23	#include <linux/ip.h>
	24	#include <linux/openvswitch.h>
	25	#include <linux/tcp.h>
	26	#include <linux/udp.h>
	27	#include <linux/in6.h>
	28	#include <linux/if_arp.h>
	29	#include <linux/if_vlan.h>
	30	#include <net/ip.h>
3fdbd1ce	31	#include <net/ipv6.h>
ccb1352e JG	32	#include <net/checksum.h>
	33	#include <net/dsfield.h>
	34
	35	#include "datapath.h"
	36	#include "vport.h"
	37
	38	static int do_execute_actions(struct datapath dp, struct sk_buff skb,
	39	const struct nlattr *attr, int len, bool keep_skb);
	40
	41	static int make_writable(struct sk_buff *skb, int write_len)
	42	{
	43	if (!skb_cloned(skb) \|\| skb_clone_writable(skb, write_len))
	44	return 0;
	45
	46	return pskb_expand_head(skb, 0, 0, GFP_ATOMIC);
	47	}
	48
39855b5b	49	/* remove VLAN header from packet and update csum accordingly. */
ccb1352e JG	50	static int __pop_vlan_tci(struct sk_buff skb, __be16 current_tci)
	51	{
	52	struct vlan_hdr *vhdr;
	53	int err;
	54
	55	err = make_writable(skb, VLAN_ETH_HLEN);
	56	if (unlikely(err))
	57	return err;
	58
	59	if (skb->ip_summed == CHECKSUM_COMPLETE)
	60	skb->csum = csum_sub(skb->csum, csum_partial(skb->data
7b024082	61	+ (2 * ETH_ALEN), VLAN_HLEN, 0));
ccb1352e JG	62
	63	vhdr = (struct vlan_hdr *)(skb->data + ETH_HLEN);
	64	*current_tci = vhdr->h_vlan_TCI;
	65
	66	memmove(skb->data + VLAN_HLEN, skb->data, 2 * ETH_ALEN);
	67	__skb_pull(skb, VLAN_HLEN);
	68
	69	vlan_set_encap_proto(skb, vhdr);
	70	skb->mac_header += VLAN_HLEN;
	71	skb_reset_mac_len(skb);
	72
	73	return 0;
	74	}
	75
	76	static int pop_vlan(struct sk_buff *skb)
	77	{
	78	__be16 tci;
	79	int err;
	80
	81	if (likely(vlan_tx_tag_present(skb))) {
	82	skb->vlan_tci = 0;
	83	} else {
	84	if (unlikely(skb->protocol != htons(ETH_P_8021Q) \|\|
	85	skb->len < VLAN_ETH_HLEN))
	86	return 0;
	87
	88	err = __pop_vlan_tci(skb, &tci);
	89	if (err)
	90	return err;
	91	}
	92	/* move next vlan tag to hw accel tag */
	93	if (likely(skb->protocol != htons(ETH_P_8021Q) \|\|
	94	skb->len < VLAN_ETH_HLEN))
	95	return 0;
	96
	97	err = __pop_vlan_tci(skb, &tci);
	98	if (unlikely(err))
	99	return err;
	100
86a9bad3	101	__vlan_hwaccel_put_tag(skb, htons(ETH_P_8021Q), ntohs(tci));
ccb1352e JG	102	return 0;
	103	}
	104
	105	static int push_vlan(struct sk_buff skb, const struct ovs_action_push_vlan vlan)
	106	{
	107	if (unlikely(vlan_tx_tag_present(skb))) {
	108	u16 current_tag;
	109
	110	/* push down current VLAN tag */
	111	current_tag = vlan_tx_tag_get(skb);
	112
86a9bad3	113	if (!__vlan_put_tag(skb, skb->vlan_proto, current_tag))
ccb1352e JG	114	return -ENOMEM;
	115
	116	if (skb->ip_summed == CHECKSUM_COMPLETE)
	117	skb->csum = csum_add(skb->csum, csum_partial(skb->data
7b024082	118	+ (2 * ETH_ALEN), VLAN_HLEN, 0));
ccb1352e JG	119
ccb1352e JG	120	}
86a9bad3	121	__vlan_hwaccel_put_tag(skb, vlan->vlan_tpid, ntohs(vlan->vlan_tci) & ~VLAN_TAG_PRESENT);
ccb1352e JG	122	return 0;
	123	}
	124
	125	static int set_eth_addr(struct sk_buff *skb,
	126	const struct ovs_key_ethernet *eth_key)
	127	{
	128	int err;
	129	err = make_writable(skb, ETH_HLEN);
	130	if (unlikely(err))
	131	return err;
	132
b34df5e8 PS	133	skb_postpull_rcsum(skb, eth_hdr(skb), ETH_ALEN * 2);
b34df5e8 PS	134
ccb1352e JG	135	memcpy(eth_hdr(skb)->h_source, eth_key->eth_src, ETH_ALEN);
	136	memcpy(eth_hdr(skb)->h_dest, eth_key->eth_dst, ETH_ALEN);
	137
b34df5e8 PS	138	ovs_skb_postpush_rcsum(skb, eth_hdr(skb), ETH_ALEN * 2);
b34df5e8 PS	139
ccb1352e JG	140	return 0;
	141	}
	142
	143	static void set_ip_addr(struct sk_buff skb, struct iphdr nh,
	144	__be32 *addr, __be32 new_addr)
	145	{
	146	int transport_len = skb->len - skb_transport_offset(skb);
	147
	148	if (nh->protocol == IPPROTO_TCP) {
	149	if (likely(transport_len >= sizeof(struct tcphdr)))
	150	inet_proto_csum_replace4(&tcp_hdr(skb)->check, skb,
	151	*addr, new_addr, 1);
	152	} else if (nh->protocol == IPPROTO_UDP) {
81e5d41d JG	153	if (likely(transport_len >= sizeof(struct udphdr))) {
	154	struct udphdr *uh = udp_hdr(skb);
	155
	156	if (uh->check \|\| skb->ip_summed == CHECKSUM_PARTIAL) {
	157	inet_proto_csum_replace4(&uh->check, skb,
	158	*addr, new_addr, 1);
	159	if (!uh->check)
	160	uh->check = CSUM_MANGLED_0;
	161	}
	162	}
ccb1352e JG	163	}
	164
	165	csum_replace4(&nh->check, *addr, new_addr);
	166	skb->rxhash = 0;
	167	*addr = new_addr;
	168	}
	169
3fdbd1ce AA	170	static void update_ipv6_checksum(struct sk_buff *skb, u8 l4_proto,
	171	__be32 addr[4], const __be32 new_addr[4])
	172	{
	173	int transport_len = skb->len - skb_transport_offset(skb);
	174
	175	if (l4_proto == IPPROTO_TCP) {
	176	if (likely(transport_len >= sizeof(struct tcphdr)))
	177	inet_proto_csum_replace16(&tcp_hdr(skb)->check, skb,
	178	addr, new_addr, 1);
	179	} else if (l4_proto == IPPROTO_UDP) {
	180	if (likely(transport_len >= sizeof(struct udphdr))) {
	181	struct udphdr *uh = udp_hdr(skb);
	182
	183	if (uh->check \|\| skb->ip_summed == CHECKSUM_PARTIAL) {
	184	inet_proto_csum_replace16(&uh->check, skb,
	185	addr, new_addr, 1);
	186	if (!uh->check)
	187	uh->check = CSUM_MANGLED_0;
	188	}
	189	}
	190	}
	191	}
	192
	193	static void set_ipv6_addr(struct sk_buff *skb, u8 l4_proto,
	194	__be32 addr[4], const __be32 new_addr[4],
	195	bool recalculate_csum)
	196	{
	197	if (recalculate_csum)
	198	update_ipv6_checksum(skb, l4_proto, addr, new_addr);
	199
	200	skb->rxhash = 0;
	201	memcpy(addr, new_addr, sizeof(__be32[4]));
	202	}
	203
	204	static void set_ipv6_tc(struct ipv6hdr *nh, u8 tc)
	205	{
	206	nh->priority = tc >> 4;
	207	nh->flow_lbl[0] = (nh->flow_lbl[0] & 0x0F) \| ((tc & 0x0F) << 4);
	208	}
	209
	210	static void set_ipv6_fl(struct ipv6hdr *nh, u32 fl)
	211	{
	212	nh->flow_lbl[0] = (nh->flow_lbl[0] & 0xF0) \| (fl & 0x000F0000) >> 16;
	213	nh->flow_lbl[1] = (fl & 0x0000FF00) >> 8;
	214	nh->flow_lbl[2] = fl & 0x000000FF;
	215	}
	216
ccb1352e JG	217	static void set_ip_ttl(struct sk_buff skb, struct iphdr nh, u8 new_ttl)
	218	{
	219	csum_replace2(&nh->check, htons(nh->ttl << 8), htons(new_ttl << 8));
	220	nh->ttl = new_ttl;
	221	}
	222
	223	static int set_ipv4(struct sk_buff skb, const struct ovs_key_ipv4 ipv4_key)
	224	{
	225	struct iphdr *nh;
	226	int err;
	227
	228	err = make_writable(skb, skb_network_offset(skb) +
	229	sizeof(struct iphdr));
	230	if (unlikely(err))
	231	return err;
	232
	233	nh = ip_hdr(skb);
	234
	235	if (ipv4_key->ipv4_src != nh->saddr)
	236	set_ip_addr(skb, nh, &nh->saddr, ipv4_key->ipv4_src);
	237
	238	if (ipv4_key->ipv4_dst != nh->daddr)
	239	set_ip_addr(skb, nh, &nh->daddr, ipv4_key->ipv4_dst);
	240
	241	if (ipv4_key->ipv4_tos != nh->tos)
	242	ipv4_change_dsfield(nh, 0, ipv4_key->ipv4_tos);
	243
	244	if (ipv4_key->ipv4_ttl != nh->ttl)
	245	set_ip_ttl(skb, nh, ipv4_key->ipv4_ttl);
	246
	247	return 0;
	248	}
	249
3fdbd1ce AA	250	static int set_ipv6(struct sk_buff skb, const struct ovs_key_ipv6 ipv6_key)
	251	{
	252	struct ipv6hdr *nh;
	253	int err;
	254	__be32 *saddr;
	255	__be32 *daddr;
	256
	257	err = make_writable(skb, skb_network_offset(skb) +
	258	sizeof(struct ipv6hdr));
	259	if (unlikely(err))
	260	return err;
	261
	262	nh = ipv6_hdr(skb);
	263	saddr = (__be32 *)&nh->saddr;
	264	daddr = (__be32 *)&nh->daddr;
	265
	266	if (memcmp(ipv6_key->ipv6_src, saddr, sizeof(ipv6_key->ipv6_src)))
	267	set_ipv6_addr(skb, ipv6_key->ipv6_proto, saddr,
	268	ipv6_key->ipv6_src, true);
	269
	270	if (memcmp(ipv6_key->ipv6_dst, daddr, sizeof(ipv6_key->ipv6_dst))) {
	271	unsigned int offset = 0;
	272	int flags = IP6_FH_F_SKIP_RH;
	273	bool recalc_csum = true;
	274
	275	if (ipv6_ext_hdr(nh->nexthdr))
	276	recalc_csum = ipv6_find_hdr(skb, &offset,
	277	NEXTHDR_ROUTING, NULL,
	278	&flags) != NEXTHDR_ROUTING;
	279
	280	set_ipv6_addr(skb, ipv6_key->ipv6_proto, daddr,
	281	ipv6_key->ipv6_dst, recalc_csum);
	282	}
	283
	284	set_ipv6_tc(nh, ipv6_key->ipv6_tclass);
	285	set_ipv6_fl(nh, ntohl(ipv6_key->ipv6_label));
	286	nh->hop_limit = ipv6_key->ipv6_hlimit;
	287
	288	return 0;
	289	}
	290
ccb1352e JG	291	/* Must follow make_writable() since that can move the skb data. */
	292	static void set_tp_port(struct sk_buff skb, __be16 port,
	293	__be16 new_port, __sum16 *check)
	294	{
	295	inet_proto_csum_replace2(check, skb, *port, new_port, 0);
	296	*port = new_port;
	297	skb->rxhash = 0;
	298	}
	299
81e5d41d JG	300	static void set_udp_port(struct sk_buff skb, __be16 port, __be16 new_port)
	301	{
	302	struct udphdr *uh = udp_hdr(skb);
	303
	304	if (uh->check && skb->ip_summed != CHECKSUM_PARTIAL) {
	305	set_tp_port(skb, port, new_port, &uh->check);
	306
	307	if (!uh->check)
	308	uh->check = CSUM_MANGLED_0;
	309	} else {
	310	*port = new_port;
	311	skb->rxhash = 0;
	312	}
	313	}
	314
	315	static int set_udp(struct sk_buff skb, const struct ovs_key_udp udp_port_key)
ccb1352e JG	316	{
	317	struct udphdr *uh;
	318	int err;
	319
	320	err = make_writable(skb, skb_transport_offset(skb) +
	321	sizeof(struct udphdr));
	322	if (unlikely(err))
	323	return err;
	324
	325	uh = udp_hdr(skb);
	326	if (udp_port_key->udp_src != uh->source)
81e5d41d	327	set_udp_port(skb, &uh->source, udp_port_key->udp_src);
ccb1352e JG	328
ccb1352e JG	329	if (udp_port_key->udp_dst != uh->dest)
81e5d41d	330	set_udp_port(skb, &uh->dest, udp_port_key->udp_dst);
ccb1352e JG	331
	332	return 0;
	333	}
	334
81e5d41d	335	static int set_tcp(struct sk_buff skb, const struct ovs_key_tcp tcp_port_key)
ccb1352e JG	336	{
	337	struct tcphdr *th;
	338	int err;
	339
	340	err = make_writable(skb, skb_transport_offset(skb) +
	341	sizeof(struct tcphdr));
	342	if (unlikely(err))
	343	return err;
	344
	345	th = tcp_hdr(skb);
	346	if (tcp_port_key->tcp_src != th->source)
	347	set_tp_port(skb, &th->source, tcp_port_key->tcp_src, &th->check);
	348
	349	if (tcp_port_key->tcp_dst != th->dest)
	350	set_tp_port(skb, &th->dest, tcp_port_key->tcp_dst, &th->check);
	351
	352	return 0;
	353	}
	354
	355	static int do_output(struct datapath dp, struct sk_buff skb, int out_port)
	356	{
	357	struct vport *vport;
	358
	359	if (unlikely(!skb))
	360	return -ENOMEM;
	361
15eac2a7	362	vport = ovs_vport_rcu(dp, out_port);
ccb1352e JG	363	if (unlikely(!vport)) {
	364	kfree_skb(skb);
	365	return -ENODEV;
	366	}
	367
	368	ovs_vport_send(vport, skb);
	369	return 0;
	370	}
	371
	372	static int output_userspace(struct datapath dp, struct sk_buff skb,
	373	const struct nlattr *attr)
	374	{
	375	struct dp_upcall_info upcall;
	376	const struct nlattr *a;
	377	int rem;
	378
	379	upcall.cmd = OVS_PACKET_CMD_ACTION;
	380	upcall.key = &OVS_CB(skb)->flow->key;
	381	upcall.userdata = NULL;
15e47304	382	upcall.portid = 0;
ccb1352e JG	383
	384	for (a = nla_data(attr), rem = nla_len(attr); rem > 0;
	385	a = nla_next(a, &rem)) {
	386	switch (nla_type(a)) {
	387	case OVS_USERSPACE_ATTR_USERDATA:
	388	upcall.userdata = a;
	389	break;
	390
	391	case OVS_USERSPACE_ATTR_PID:
15e47304	392	upcall.portid = nla_get_u32(a);
ccb1352e JG	393	break;
	394	}
	395	}
	396
	397	return ovs_dp_upcall(dp, skb, &upcall);
	398	}
	399
	400	static int sample(struct datapath dp, struct sk_buff skb,
	401	const struct nlattr *attr)
	402	{
	403	const struct nlattr *acts_list = NULL;
	404	const struct nlattr *a;
	405	int rem;
	406
	407	for (a = nla_data(attr), rem = nla_len(attr); rem > 0;
	408	a = nla_next(a, &rem)) {
	409	switch (nla_type(a)) {
	410	case OVS_SAMPLE_ATTR_PROBABILITY:
	411	if (net_random() >= nla_get_u32(a))
	412	return 0;
	413	break;
	414
	415	case OVS_SAMPLE_ATTR_ACTIONS:
	416	acts_list = a;
	417	break;
	418	}
	419	}
	420
	421	return do_execute_actions(dp, skb, nla_data(acts_list),
	422	nla_len(acts_list), true);
	423	}
	424
	425	static int execute_set_action(struct sk_buff *skb,
	426	const struct nlattr *nested_attr)
	427	{
	428	int err = 0;
	429
	430	switch (nla_type(nested_attr)) {
	431	case OVS_KEY_ATTR_PRIORITY:
	432	skb->priority = nla_get_u32(nested_attr);
	433	break;
	434
39c7caeb AA	435	case OVS_KEY_ATTR_SKB_MARK:
	436	skb->mark = nla_get_u32(nested_attr);
	437	break;
	438
ccb1352e JG	439	case OVS_KEY_ATTR_ETHERNET:
	440	err = set_eth_addr(skb, nla_data(nested_attr));
	441	break;
	442
	443	case OVS_KEY_ATTR_IPV4:
	444	err = set_ipv4(skb, nla_data(nested_attr));
	445	break;
	446
3fdbd1ce AA	447	case OVS_KEY_ATTR_IPV6:
	448	err = set_ipv6(skb, nla_data(nested_attr));
	449	break;
	450
ccb1352e	451	case OVS_KEY_ATTR_TCP:
81e5d41d	452	err = set_tcp(skb, nla_data(nested_attr));
ccb1352e JG	453	break;
	454
	455	case OVS_KEY_ATTR_UDP:
81e5d41d	456	err = set_udp(skb, nla_data(nested_attr));
ccb1352e JG	457	break;
	458	}
	459
	460	return err;
	461	}
	462
	463	/* Execute a list of actions against 'skb'. */
	464	static int do_execute_actions(struct datapath dp, struct sk_buff skb,
	465	const struct nlattr *attr, int len, bool keep_skb)
	466	{
	467	/* Every output action needs a separate clone of 'skb', but the common
	468	* case is just a single output action, so that doing a clone and
	469	* then freeing the original skbuff is wasteful. So the following code
	470	* is slightly obscure just to avoid that. */
	471	int prev_port = -1;
	472	const struct nlattr *a;
	473	int rem;
	474
	475	for (a = attr, rem = len; rem > 0;
	476	a = nla_next(a, &rem)) {
	477	int err = 0;
	478
	479	if (prev_port != -1) {
	480	do_output(dp, skb_clone(skb, GFP_ATOMIC), prev_port);
	481	prev_port = -1;
	482	}
	483
	484	switch (nla_type(a)) {
	485	case OVS_ACTION_ATTR_OUTPUT:
	486	prev_port = nla_get_u32(a);
	487	break;
	488
	489	case OVS_ACTION_ATTR_USERSPACE:
	490	output_userspace(dp, skb, a);
	491	break;
	492
	493	case OVS_ACTION_ATTR_PUSH_VLAN:
	494	err = push_vlan(skb, nla_data(a));
	495	if (unlikely(err)) /* skb already freed. */
	496	return err;
	497	break;
	498
	499	case OVS_ACTION_ATTR_POP_VLAN:
	500	err = pop_vlan(skb);
	501	break;
	502
	503	case OVS_ACTION_ATTR_SET:
	504	err = execute_set_action(skb, nla_data(a));
	505	break;
	506
	507	case OVS_ACTION_ATTR_SAMPLE:
	508	err = sample(dp, skb, a);
	509	break;
	510	}
	511
	512	if (unlikely(err)) {
	513	kfree_skb(skb);
	514	return err;
	515	}
	516	}
	517
	518	if (prev_port != -1) {
	519	if (keep_skb)
	520	skb = skb_clone(skb, GFP_ATOMIC);
521
522	do_output(dp, skb, prev_port);
523	} else if (!keep_skb)
524	consume_skb(skb);
525
526	return 0;
527	}
528
529	/* Execute a list of actions against 'skb'. */
530	int ovs_execute_actions(struct datapath dp, struct sk_buff skb)
531	{
532	struct sw_flow_actions *acts = rcu_dereference(OVS_CB(skb)->flow->sf_acts);
533
534	return do_execute_actions(dp, skb, acts->actions,
535	acts->actions_len, false);
536	}