linux/net/openvswitch/actions.c
Jarno Rajahalme 83d2b9ba1a net: openvswitch: Support masked set actions.
OVS userspace already probes the openvswitch kernel module for
OVS_ACTION_ATTR_SET_MASKED support.  This patch adds the kernel module
implementation of masked set actions.

The existing set action sets many fields at once.  When only a subset
of the IP header fields, for example, should be modified, all the IP
fields need to be exact matched so that the other field values can be
copied to the set action.  A masked set action allows modification of
an arbitrary subset of the supported header bits without requiring the
rest to be matched.

Masked set action is now supported for all writeable key types, except
for the tunnel key.  The set tunnel action is an exception as any
input tunnel info is cleared before action processing starts, so there
is no tunnel info to mask.

The kernel module converts all (non-tunnel) set actions to masked set
actions.  This makes action processing more uniform, and results in
less branching and duplicating the action processing code.  When
returning actions to userspace, the fully masked set actions are
converted back to normal set actions.  We use a kernel internal action
code to be able to tell the userspace provided and converted masked
set actions apart.

Signed-off-by: Jarno Rajahalme <jrajahalme@nicira.com>
Acked-by: Pravin B Shelar <pshelar@nicira.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-02-07 22:40:17 -08:00

996 lines
24 KiB
C

/*
* Copyright (c) 2007-2014 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/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/ip.h>
#include <net/ipv6.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 "vport.h"
static int do_execute_actions(struct datapath *dp, struct sk_buff *skb,
struct sw_flow_key *key,
const struct nlattr *attr, int len);
struct deferred_action {
struct sk_buff *skb;
const struct nlattr *actions;
/* Store pkt_key clone when creating deferred action. */
struct sw_flow_key pkt_key;
};
#define DEFERRED_ACTION_FIFO_SIZE 10
struct action_fifo {
int head;
int tail;
/* Deferred action fifo queue storage. */
struct deferred_action fifo[DEFERRED_ACTION_FIFO_SIZE];
};
static struct action_fifo __percpu *action_fifos;
static DEFINE_PER_CPU(int, exec_actions_level);
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 *attr)
{
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 = attr;
da->pkt_key = *key;
}
return da;
}
static void invalidate_flow_key(struct sw_flow_key *key)
{
key->eth.type = htons(0);
}
static bool is_flow_key_valid(const struct sw_flow_key *key)
{
return !!key->eth.type;
}
static int push_mpls(struct sk_buff *skb, struct sw_flow_key *key,
const struct ovs_action_push_mpls *mpls)
{
__be32 *new_mpls_lse;
struct ethhdr *hdr;
/* Networking stack do not allow simultaneous Tunnel and MPLS GSO. */
if (skb->encapsulation)
return -ENOTSUPP;
if (skb_cow_head(skb, MPLS_HLEN) < 0)
return -ENOMEM;
skb_push(skb, MPLS_HLEN);
memmove(skb_mac_header(skb) - MPLS_HLEN, skb_mac_header(skb),
skb->mac_len);
skb_reset_mac_header(skb);
new_mpls_lse = (__be32 *)skb_mpls_header(skb);
*new_mpls_lse = mpls->mpls_lse;
if (skb->ip_summed == CHECKSUM_COMPLETE)
skb->csum = csum_add(skb->csum, csum_partial(new_mpls_lse,
MPLS_HLEN, 0));
hdr = eth_hdr(skb);
hdr->h_proto = mpls->mpls_ethertype;
if (!skb->inner_protocol)
skb_set_inner_protocol(skb, skb->protocol);
skb->protocol = mpls->mpls_ethertype;
invalidate_flow_key(key);
return 0;
}
static int pop_mpls(struct sk_buff *skb, struct sw_flow_key *key,
const __be16 ethertype)
{
struct ethhdr *hdr;
int err;
err = skb_ensure_writable(skb, skb->mac_len + MPLS_HLEN);
if (unlikely(err))
return err;
skb_postpull_rcsum(skb, skb_mpls_header(skb), MPLS_HLEN);
memmove(skb_mac_header(skb) + MPLS_HLEN, skb_mac_header(skb),
skb->mac_len);
__skb_pull(skb, MPLS_HLEN);
skb_reset_mac_header(skb);
/* skb_mpls_header() is used to locate the ethertype
* field correctly in the presence of VLAN tags.
*/
hdr = (struct ethhdr *)(skb_mpls_header(skb) - ETH_HLEN);
hdr->h_proto = ethertype;
if (eth_p_mpls(skb->protocol))
skb->protocol = ethertype;
invalidate_flow_key(key);
return 0;
}
/* 'KEY' must not have any bits set outside of the 'MASK' */
#define MASKED(OLD, KEY, MASK) ((KEY) | ((OLD) & ~(MASK)))
#define SET_MASKED(OLD, KEY, MASK) ((OLD) = MASKED(OLD, KEY, MASK))
static int set_mpls(struct sk_buff *skb, struct sw_flow_key *flow_key,
const __be32 *mpls_lse, const __be32 *mask)
{
__be32 *stack;
__be32 lse;
int err;
err = skb_ensure_writable(skb, skb->mac_len + MPLS_HLEN);
if (unlikely(err))
return err;
stack = (__be32 *)skb_mpls_header(skb);
lse = MASKED(*stack, *mpls_lse, *mask);
if (skb->ip_summed == CHECKSUM_COMPLETE) {
__be32 diff[] = { ~(*stack), lse };
skb->csum = ~csum_partial((char *)diff, sizeof(diff),
~skb->csum);
}
*stack = lse;
flow_key->mpls.top_lse = lse;
return 0;
}
static int pop_vlan(struct sk_buff *skb, struct sw_flow_key *key)
{
int err;
err = skb_vlan_pop(skb);
if (skb_vlan_tag_present(skb))
invalidate_flow_key(key);
else
key->eth.tci = 0;
return err;
}
static int push_vlan(struct sk_buff *skb, struct sw_flow_key *key,
const struct ovs_action_push_vlan *vlan)
{
if (skb_vlan_tag_present(skb))
invalidate_flow_key(key);
else
key->eth.tci = vlan->vlan_tci;
return skb_vlan_push(skb, vlan->vlan_tpid,
ntohs(vlan->vlan_tci) & ~VLAN_TAG_PRESENT);
}
/* 'src' is already properly masked. */
static void ether_addr_copy_masked(u8 *dst_, const u8 *src_, const u8 *mask_)
{
u16 *dst = (u16 *)dst_;
const u16 *src = (const u16 *)src_;
const u16 *mask = (const u16 *)mask_;
SET_MASKED(dst[0], src[0], mask[0]);
SET_MASKED(dst[1], src[1], mask[1]);
SET_MASKED(dst[2], src[2], mask[2]);
}
static int set_eth_addr(struct sk_buff *skb, struct sw_flow_key *flow_key,
const struct ovs_key_ethernet *key,
const struct ovs_key_ethernet *mask)
{
int err;
err = skb_ensure_writable(skb, ETH_HLEN);
if (unlikely(err))
return err;
skb_postpull_rcsum(skb, eth_hdr(skb), ETH_ALEN * 2);
ether_addr_copy_masked(eth_hdr(skb)->h_source, key->eth_src,
mask->eth_src);
ether_addr_copy_masked(eth_hdr(skb)->h_dest, key->eth_dst,
mask->eth_dst);
ovs_skb_postpush_rcsum(skb, eth_hdr(skb), ETH_ALEN * 2);
ether_addr_copy(flow_key->eth.src, eth_hdr(skb)->h_source);
ether_addr_copy(flow_key->eth.dst, eth_hdr(skb)->h_dest);
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_clear_hash(skb);
*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 == NEXTHDR_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 == NEXTHDR_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;
}
}
} else if (l4_proto == NEXTHDR_ICMP) {
if (likely(transport_len >= sizeof(struct icmp6hdr)))
inet_proto_csum_replace16(&icmp6_hdr(skb)->icmp6_cksum,
skb, addr, new_addr, 1);
}
}
static void mask_ipv6_addr(const __be32 old[4], const __be32 addr[4],
const __be32 mask[4], __be32 masked[4])
{
masked[0] = MASKED(old[0], addr[0], mask[0]);
masked[1] = MASKED(old[1], addr[1], mask[1]);
masked[2] = MASKED(old[2], addr[2], mask[2]);
masked[3] = MASKED(old[3], addr[3], mask[3]);
}
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_clear_hash(skb);
memcpy(addr, new_addr, sizeof(__be32[4]));
}
static void set_ipv6_fl(struct ipv6hdr *nh, u32 fl, u32 mask)
{
/* Bits 21-24 are always unmasked, so this retains their values. */
SET_MASKED(nh->flow_lbl[0], (u8)(fl >> 16), (u8)(mask >> 16));
SET_MASKED(nh->flow_lbl[1], (u8)(fl >> 8), (u8)(mask >> 8));
SET_MASKED(nh->flow_lbl[2], (u8)fl, (u8)mask);
}
static void set_ip_ttl(struct sk_buff *skb, struct iphdr *nh, u8 new_ttl,
u8 mask)
{
new_ttl = MASKED(nh->ttl, new_ttl, mask);
csum_replace2(&nh->check, htons(nh->ttl << 8), htons(new_ttl << 8));
nh->ttl = new_ttl;
}
static int set_ipv4(struct sk_buff *skb, struct sw_flow_key *flow_key,
const struct ovs_key_ipv4 *key,
const struct ovs_key_ipv4 *mask)
{
struct iphdr *nh;
__be32 new_addr;
int err;
err = skb_ensure_writable(skb, skb_network_offset(skb) +
sizeof(struct iphdr));
if (unlikely(err))
return err;
nh = ip_hdr(skb);
/* Setting an IP addresses is typically only a side effect of
* matching on them in the current userspace implementation, so it
* makes sense to check if the value actually changed.
*/
if (mask->ipv4_src) {
new_addr = MASKED(nh->saddr, key->ipv4_src, mask->ipv4_src);
if (unlikely(new_addr != nh->saddr)) {
set_ip_addr(skb, nh, &nh->saddr, new_addr);
flow_key->ipv4.addr.src = new_addr;
}
}
if (mask->ipv4_dst) {
new_addr = MASKED(nh->daddr, key->ipv4_dst, mask->ipv4_dst);
if (unlikely(new_addr != nh->daddr)) {
set_ip_addr(skb, nh, &nh->daddr, new_addr);
flow_key->ipv4.addr.dst = new_addr;
}
}
if (mask->ipv4_tos) {
ipv4_change_dsfield(nh, ~mask->ipv4_tos, key->ipv4_tos);
flow_key->ip.tos = nh->tos;
}
if (mask->ipv4_ttl) {
set_ip_ttl(skb, nh, key->ipv4_ttl, mask->ipv4_ttl);
flow_key->ip.ttl = nh->ttl;
}
return 0;
}
static bool is_ipv6_mask_nonzero(const __be32 addr[4])
{
return !!(addr[0] | addr[1] | addr[2] | addr[3]);
}
static int set_ipv6(struct sk_buff *skb, struct sw_flow_key *flow_key,
const struct ovs_key_ipv6 *key,
const struct ovs_key_ipv6 *mask)
{
struct ipv6hdr *nh;
int err;
err = skb_ensure_writable(skb, skb_network_offset(skb) +
sizeof(struct ipv6hdr));
if (unlikely(err))
return err;
nh = ipv6_hdr(skb);
/* Setting an IP addresses is typically only a side effect of
* matching on them in the current userspace implementation, so it
* makes sense to check if the value actually changed.
*/
if (is_ipv6_mask_nonzero(mask->ipv6_src)) {
__be32 *saddr = (__be32 *)&nh->saddr;
__be32 masked[4];
mask_ipv6_addr(saddr, key->ipv6_src, mask->ipv6_src, masked);
if (unlikely(memcmp(saddr, masked, sizeof(masked)))) {
set_ipv6_addr(skb, key->ipv6_proto, saddr, masked,
true);
memcpy(&flow_key->ipv6.addr.src, masked,
sizeof(flow_key->ipv6.addr.src));
}
}
if (is_ipv6_mask_nonzero(mask->ipv6_dst)) {
unsigned int offset = 0;
int flags = IP6_FH_F_SKIP_RH;
bool recalc_csum = true;
__be32 *daddr = (__be32 *)&nh->daddr;
__be32 masked[4];
mask_ipv6_addr(daddr, key->ipv6_dst, mask->ipv6_dst, masked);
if (unlikely(memcmp(daddr, masked, sizeof(masked)))) {
if (ipv6_ext_hdr(nh->nexthdr))
recalc_csum = (ipv6_find_hdr(skb, &offset,
NEXTHDR_ROUTING,
NULL, &flags)
!= NEXTHDR_ROUTING);
set_ipv6_addr(skb, key->ipv6_proto, daddr, masked,
recalc_csum);
memcpy(&flow_key->ipv6.addr.dst, masked,
sizeof(flow_key->ipv6.addr.dst));
}
}
if (mask->ipv6_tclass) {
ipv6_change_dsfield(nh, ~mask->ipv6_tclass, key->ipv6_tclass);
flow_key->ip.tos = ipv6_get_dsfield(nh);
}
if (mask->ipv6_label) {
set_ipv6_fl(nh, ntohl(key->ipv6_label),
ntohl(mask->ipv6_label));
flow_key->ipv6.label =
*(__be32 *)nh & htonl(IPV6_FLOWINFO_FLOWLABEL);
}
if (mask->ipv6_hlimit) {
SET_MASKED(nh->hop_limit, key->ipv6_hlimit, mask->ipv6_hlimit);
flow_key->ip.ttl = nh->hop_limit;
}
return 0;
}
/* Must follow skb_ensure_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;
}
static int set_udp(struct sk_buff *skb, struct sw_flow_key *flow_key,
const struct ovs_key_udp *key,
const struct ovs_key_udp *mask)
{
struct udphdr *uh;
__be16 src, dst;
int err;
err = skb_ensure_writable(skb, skb_transport_offset(skb) +
sizeof(struct udphdr));
if (unlikely(err))
return err;
uh = udp_hdr(skb);
/* Either of the masks is non-zero, so do not bother checking them. */
src = MASKED(uh->source, key->udp_src, mask->udp_src);
dst = MASKED(uh->dest, key->udp_dst, mask->udp_dst);
if (uh->check && skb->ip_summed != CHECKSUM_PARTIAL) {
if (likely(src != uh->source)) {
set_tp_port(skb, &uh->source, src, &uh->check);
flow_key->tp.src = src;
}
if (likely(dst != uh->dest)) {
set_tp_port(skb, &uh->dest, dst, &uh->check);
flow_key->tp.dst = dst;
}
if (unlikely(!uh->check))
uh->check = CSUM_MANGLED_0;
} else {
uh->source = src;
uh->dest = dst;
flow_key->tp.src = src;
flow_key->tp.dst = dst;
}
skb_clear_hash(skb);
return 0;
}
static int set_tcp(struct sk_buff *skb, struct sw_flow_key *flow_key,
const struct ovs_key_tcp *key,
const struct ovs_key_tcp *mask)
{
struct tcphdr *th;
__be16 src, dst;
int err;
err = skb_ensure_writable(skb, skb_transport_offset(skb) +
sizeof(struct tcphdr));
if (unlikely(err))
return err;
th = tcp_hdr(skb);
src = MASKED(th->source, key->tcp_src, mask->tcp_src);
if (likely(src != th->source)) {
set_tp_port(skb, &th->source, src, &th->check);
flow_key->tp.src = src;
}
dst = MASKED(th->dest, key->tcp_dst, mask->tcp_dst);
if (likely(dst != th->dest)) {
set_tp_port(skb, &th->dest, dst, &th->check);
flow_key->tp.dst = dst;
}
skb_clear_hash(skb);
return 0;
}
static int set_sctp(struct sk_buff *skb, struct sw_flow_key *flow_key,
const struct ovs_key_sctp *key,
const struct ovs_key_sctp *mask)
{
unsigned int sctphoff = skb_transport_offset(skb);
struct sctphdr *sh;
__le32 old_correct_csum, new_csum, old_csum;
int err;
err = skb_ensure_writable(skb, sctphoff + sizeof(struct sctphdr));
if (unlikely(err))
return err;
sh = sctp_hdr(skb);
old_csum = sh->checksum;
old_correct_csum = sctp_compute_cksum(skb, sctphoff);
sh->source = MASKED(sh->source, key->sctp_src, mask->sctp_src);
sh->dest = MASKED(sh->dest, key->sctp_dst, mask->sctp_dst);
new_csum = sctp_compute_cksum(skb, sctphoff);
/* Carry any checksum errors through. */
sh->checksum = old_csum ^ old_correct_csum ^ new_csum;
skb_clear_hash(skb);
flow_key->tp.src = sh->source;
flow_key->tp.dst = sh->dest;
return 0;
}
static void do_output(struct datapath *dp, struct sk_buff *skb, int out_port)
{
struct vport *vport = ovs_vport_rcu(dp, out_port);
if (likely(vport))
ovs_vport_send(vport, skb);
else
kfree_skb(skb);
}
static int output_userspace(struct datapath *dp, struct sk_buff *skb,
struct sw_flow_key *key, const struct nlattr *attr)
{
struct ovs_tunnel_info info;
struct dp_upcall_info upcall;
const struct nlattr *a;
int rem;
upcall.cmd = OVS_PACKET_CMD_ACTION;
upcall.userdata = NULL;
upcall.portid = 0;
upcall.egress_tun_info = NULL;
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;
case OVS_USERSPACE_ATTR_EGRESS_TUN_PORT: {
/* Get out tunnel info. */
struct vport *vport;
vport = ovs_vport_rcu(dp, nla_get_u32(a));
if (vport) {
int err;
err = ovs_vport_get_egress_tun_info(vport, skb,
&info);
if (!err)
upcall.egress_tun_info = &info;
}
break;
}
} /* End of switch. */
}
return ovs_dp_upcall(dp, skb, key, &upcall);
}
static int sample(struct datapath *dp, struct sk_buff *skb,
struct sw_flow_key *key, 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 (prandom_u32() >= nla_get_u32(a))
return 0;
break;
case OVS_SAMPLE_ATTR_ACTIONS:
acts_list = a;
break;
}
}
rem = nla_len(acts_list);
a = nla_data(acts_list);
/* Actions list is empty, do nothing */
if (unlikely(!rem))
return 0;
/* The only known usage of sample action is having a single user-space
* action. Treat this usage as a special case.
* The output_userspace() should clone the skb to be sent to the
* user space. This skb will be consumed by its caller.
*/
if (likely(nla_type(a) == OVS_ACTION_ATTR_USERSPACE &&
nla_is_last(a, rem)))
return output_userspace(dp, skb, key, a);
skb = skb_clone(skb, GFP_ATOMIC);
if (!skb)
/* Skip the sample action when out of memory. */
return 0;
if (!add_deferred_actions(skb, key, a)) {
if (net_ratelimit())
pr_warn("%s: deferred actions limit reached, dropping sample action\n",
ovs_dp_name(dp));
kfree_skb(skb);
}
return 0;
}
static void execute_hash(struct sk_buff *skb, struct sw_flow_key *key,
const struct nlattr *attr)
{
struct ovs_action_hash *hash_act = nla_data(attr);
u32 hash = 0;
/* OVS_HASH_ALG_L4 is the only possible hash algorithm. */
hash = skb_get_hash(skb);
hash = jhash_1word(hash, hash_act->hash_basis);
if (!hash)
hash = 0x1;
key->ovs_flow_hash = hash;
}
static int execute_set_action(struct sk_buff *skb,
struct sw_flow_key *flow_key,
const struct nlattr *a)
{
/* Only tunnel set execution is supported without a mask. */
if (nla_type(a) == OVS_KEY_ATTR_TUNNEL_INFO) {
OVS_CB(skb)->egress_tun_info = nla_data(a);
return 0;
}
return -EINVAL;
}
/* Mask is at the midpoint of the data. */
#define get_mask(a, type) ((const type)nla_data(a) + 1)
static int execute_masked_set_action(struct sk_buff *skb,
struct sw_flow_key *flow_key,
const struct nlattr *a)
{
int err = 0;
switch (nla_type(a)) {
case OVS_KEY_ATTR_PRIORITY:
SET_MASKED(skb->priority, nla_get_u32(a), *get_mask(a, u32 *));
flow_key->phy.priority = skb->priority;
break;
case OVS_KEY_ATTR_SKB_MARK:
SET_MASKED(skb->mark, nla_get_u32(a), *get_mask(a, u32 *));
flow_key->phy.skb_mark = skb->mark;
break;
case OVS_KEY_ATTR_TUNNEL_INFO:
/* Masked data not supported for tunnel. */
err = -EINVAL;
break;
case OVS_KEY_ATTR_ETHERNET:
err = set_eth_addr(skb, flow_key, nla_data(a),
get_mask(a, struct ovs_key_ethernet *));
break;
case OVS_KEY_ATTR_IPV4:
err = set_ipv4(skb, flow_key, nla_data(a),
get_mask(a, struct ovs_key_ipv4 *));
break;
case OVS_KEY_ATTR_IPV6:
err = set_ipv6(skb, flow_key, nla_data(a),
get_mask(a, struct ovs_key_ipv6 *));
break;
case OVS_KEY_ATTR_TCP:
err = set_tcp(skb, flow_key, nla_data(a),
get_mask(a, struct ovs_key_tcp *));
break;
case OVS_KEY_ATTR_UDP:
err = set_udp(skb, flow_key, nla_data(a),
get_mask(a, struct ovs_key_udp *));
break;
case OVS_KEY_ATTR_SCTP:
err = set_sctp(skb, flow_key, nla_data(a),
get_mask(a, struct ovs_key_sctp *));
break;
case OVS_KEY_ATTR_MPLS:
err = set_mpls(skb, flow_key, nla_data(a), get_mask(a,
__be32 *));
break;
}
return err;
}
static int execute_recirc(struct datapath *dp, struct sk_buff *skb,
struct sw_flow_key *key,
const struct nlattr *a, int rem)
{
struct deferred_action *da;
if (!is_flow_key_valid(key)) {
int err;
err = ovs_flow_key_update(skb, key);
if (err)
return err;
}
BUG_ON(!is_flow_key_valid(key));
if (!nla_is_last(a, rem)) {
/* Recirc action is the not the last action
* of the action list, need to clone the skb.
*/
skb = skb_clone(skb, GFP_ATOMIC);
/* Skip the recirc action when out of memory, but
* continue on with the rest of the action list.
*/
if (!skb)
return 0;
}
da = add_deferred_actions(skb, key, NULL);
if (da) {
da->pkt_key.recirc_id = nla_get_u32(a);
} else {
kfree_skb(skb);
if (net_ratelimit())
pr_warn("%s: deferred action limit reached, drop recirc action\n",
ovs_dp_name(dp));
}
return 0;
}
/* Execute a list of actions against 'skb'. */
static int do_execute_actions(struct datapath *dp, struct sk_buff *skb,
struct sw_flow_key *key,
const struct nlattr *attr, int len)
{
/* 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 (unlikely(prev_port != -1)) {
struct sk_buff *out_skb = skb_clone(skb, GFP_ATOMIC);
if (out_skb)
do_output(dp, out_skb, 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, key, a);
break;
case OVS_ACTION_ATTR_HASH:
execute_hash(skb, key, a);
break;
case OVS_ACTION_ATTR_PUSH_MPLS:
err = push_mpls(skb, key, nla_data(a));
break;
case OVS_ACTION_ATTR_POP_MPLS:
err = pop_mpls(skb, key, nla_get_be16(a));
break;
case OVS_ACTION_ATTR_PUSH_VLAN:
err = push_vlan(skb, key, nla_data(a));
break;
case OVS_ACTION_ATTR_POP_VLAN:
err = pop_vlan(skb, key);
break;
case OVS_ACTION_ATTR_RECIRC:
err = execute_recirc(dp, skb, key, a, rem);
if (nla_is_last(a, rem)) {
/* If this is the last action, the skb has
* been consumed or freed.
* Return immediately.
*/
return err;
}
break;
case OVS_ACTION_ATTR_SET:
err = execute_set_action(skb, key, nla_data(a));
break;
case OVS_ACTION_ATTR_SET_MASKED:
case OVS_ACTION_ATTR_SET_TO_MASKED:
err = execute_masked_set_action(skb, key, nla_data(a));
break;
case OVS_ACTION_ATTR_SAMPLE:
err = sample(dp, skb, key, a);
break;
}
if (unlikely(err)) {
kfree_skb(skb);
return err;
}
}
if (prev_port != -1)
do_output(dp, skb, prev_port);
else
consume_skb(skb);
return 0;
}
static void process_deferred_actions(struct datapath *dp)
{
struct action_fifo *fifo = this_cpu_ptr(action_fifos);
/* Do not touch the FIFO in case there is no deferred actions. */
if (action_fifo_is_empty(fifo))
return;
/* Finishing executing all deferred actions. */
do {
struct deferred_action *da = action_fifo_get(fifo);
struct sk_buff *skb = da->skb;
struct sw_flow_key *key = &da->pkt_key;
const struct nlattr *actions = da->actions;
if (actions)
do_execute_actions(dp, skb, key, actions,
nla_len(actions));
else
ovs_dp_process_packet(skb, key);
} while (!action_fifo_is_empty(fifo));
/* Reset FIFO for the next packet. */
action_fifo_init(fifo);
}
/* Execute a list of actions against 'skb'. */
int ovs_execute_actions(struct datapath *dp, struct sk_buff *skb,
const struct sw_flow_actions *acts,
struct sw_flow_key *key)
{
int level = this_cpu_read(exec_actions_level);
int err;
this_cpu_inc(exec_actions_level);
OVS_CB(skb)->egress_tun_info = NULL;
err = do_execute_actions(dp, skb, key,
acts->actions, acts->actions_len);
if (!level)
process_deferred_actions(dp);
this_cpu_dec(exec_actions_level);
return err;
}
int action_fifos_init(void)
{
action_fifos = alloc_percpu(struct action_fifo);
if (!action_fifos)
return -ENOMEM;
return 0;
}
void action_fifos_exit(void)
{
free_percpu(action_fifos);
}