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android-kvm / linux / 53e87e3cdc155f20c3417b689df8d2ac88d79576 / . / net / openvswitch / actions.c
blob: 076774034bb960b16c04609cd120fd5118829538 [file] [log] [blame]
// 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"
#include "openvswitch_trace.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;
invalidate_flow_key(key);
return 0;
}
static int set_mpls(struct sk_buff *skb, struct sw_flow_key *flow_key,
const __be32 *mpls_lse, const __be32 *mask)
{
struct mpls_shim_hdr *stack;
__be32 lse;
int err;
if (!pskb_may_pull(skb, skb_network_offset(skb) + MPLS_HLEN))
return -ENOMEM;
stack = mpls_hdr(skb);
lse = OVS_MASKED(stack->label_stack_entry, *mpls_lse, *mask);
err = skb_mpls_update_lse(skb, lse);
if (err)
return err;
flow_key->mpls.lse[0] = 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.vlan.tci = 0;
key->eth.vlan.tpid = 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.vlan.tci = vlan->vlan_tci;
key->eth.vlan.tpid = vlan->vlan_tpid;
}
return skb_vlan_push(skb, vlan->vlan_tpid,
ntohs(vlan->vlan_tci) & ~VLAN_CFI_MASK);
}
/* '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_;
OVS_SET_MASKED(dst[0], src[0], mask[0]);
OVS_SET_MASKED(dst[1], src[1], mask[1]);
OVS_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);
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;
}
/* pop_eth does not support VLAN packets as this action is never called
* for them.
*/
static int pop_eth(struct sk_buff *skb, struct sw_flow_key *key)
{
int err;
err = skb_eth_pop(skb);
if (err)
return err;
/* safe right before invalidate_flow_key */
key->mac_proto = MAC_PROTO_NONE;
invalidate_flow_key(key);
return 0;
}
static int push_eth(struct sk_buff *skb, struct sw_flow_key *key,
const struct ovs_action_push_eth *ethh)
{
int err;
err = skb_eth_push(skb, ethh->addresses.eth_dst,
ethh->addresses.eth_src);
if (err)
return err;
/* safe right before invalidate_flow_key */
key->mac_proto = MAC_PROTO_ETHERNET;
invalidate_flow_key(key);
return 0;
}
static int push_nsh(struct sk_buff *skb, struct sw_flow_key *key,
const struct nshhdr *nh)
{
int err;
err = nsh_push(skb, nh);
if (err)
return err;
/* safe right before invalidate_flow_key */
key->mac_proto = MAC_PROTO_NONE;
invalidate_flow_key(key);
return 0;
}
static int pop_nsh(struct sk_buff *skb, struct sw_flow_key *key)
{
int err;
err = nsh_pop(skb);
if (err)
return err;
/* safe right before invalidate_flow_key */
if (skb->protocol == htons(ETH_P_TEB))
key->mac_proto = MAC_PROTO_ETHERNET;
else
key->mac_proto = MAC_PROTO_NONE;
invalidate_flow_key(key);
return 0;
}
static void update_ip_l4_checksum(struct sk_buff *skb, struct iphdr *nh,
__be32 addr, __be32 new_addr)
{
int transport_len = skb->len - skb_transport_offset(skb);
if (nh->frag_off & htons(IP_OFFSET))
return;
if (nh->protocol == IPPROTO_TCP) {
if (likely(transport_len >= sizeof(struct tcphdr)))
inet_proto_csum_replace4(&tcp_hdr(skb)->check, skb,
addr, new_addr, true);
} 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, true);
if (!uh->check)
uh->check = CSUM_MANGLED_0;
}
}
}
}
static void set_ip_addr(struct sk_buff *skb, struct iphdr *nh,
__be32 *addr, __be32 new_addr)
{
update_ip_l4_checksum(skb, nh, *addr, new_addr);
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, true);
} 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, true);
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, true);
}
}
static void mask_ipv6_addr(const __be32 old[4], const __be32 addr[4],
const __be32 mask[4], __be32 masked[4])
{
masked[0] = OVS_MASKED(old[0], addr[0], mask[0]);
masked[1] = OVS_MASKED(old[1], addr[1], mask[1]);
masked[2] = OVS_MASKED(old[2], addr[2], mask[2]);
masked[3] = OVS_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. */
OVS_SET_MASKED(nh->flow_lbl[0], (u8)(fl >> 16), (u8)(mask >> 16));
OVS_SET_MASKED(nh->flow_lbl[1], (u8)(fl >> 8), (u8)(mask >> 8));
OVS_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 = OVS_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 = OVS_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 = OVS_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, flow_key->ip.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, flow_key->ip.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) {
OVS_SET_MASKED(nh->hop_limit, key->ipv6_hlimit,
mask->ipv6_hlimit);
flow_key->ip.ttl = nh->hop_limit;
}
return 0;
}
static int set_nsh(struct sk_buff *skb, struct sw_flow_key *flow_key,
const struct nlattr *a)
{
struct nshhdr *nh;
size_t length;
int err;
u8 flags;
u8 ttl;
int i;
struct ovs_key_nsh key;
struct ovs_key_nsh mask;
err = nsh_key_from_nlattr(a, &key, &mask);
if (err)
return err;
/* Make sure the NSH base header is there */
if (!pskb_may_pull(skb, skb_network_offset(skb) + NSH_BASE_HDR_LEN))
return -ENOMEM;
nh = nsh_hdr(skb);
length = nsh_hdr_len(nh);
/* Make sure the whole NSH header is there */
err = skb_ensure_writable(skb, skb_network_offset(skb) +
length);
if (unlikely(err))
return err;
nh = nsh_hdr(skb);
skb_postpull_rcsum(skb, nh, length);
flags = nsh_get_flags(nh);
flags = OVS_MASKED(flags, key.base.flags, mask.base.flags);
flow_key->nsh.base.flags = flags;
ttl = nsh_get_ttl(nh);
ttl = OVS_MASKED(ttl, key.base.ttl, mask.base.ttl);
flow_key->nsh.base.ttl = ttl;
nsh_set_flags_and_ttl(nh, flags, ttl);
nh->path_hdr = OVS_MASKED(nh->path_hdr, key.base.path_hdr,
mask.base.path_hdr);
flow_key->nsh.base.path_hdr = nh->path_hdr;
switch (nh->mdtype) {
case NSH_M_TYPE1:
for (i = 0; i < NSH_MD1_CONTEXT_SIZE; i++) {
nh->md1.context[i] =
OVS_MASKED(nh->md1.context[i], key.context[i],
mask.context[i]);
}
memcpy(flow_key->nsh.context, nh->md1.context,
sizeof(nh->md1.context));
break;
case NSH_M_TYPE2:
memset(flow_key->nsh.context, 0,
sizeof(flow_key->nsh.context));
break;
default:
return -EINVAL;
}
skb_postpush_rcsum(skb, nh, length);
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, false);
*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 = OVS_MASKED(uh->source, key->udp_src, mask->udp_src);
dst = OVS_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 = OVS_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 = OVS_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 = OVS_MASKED(sh->source, key->sctp_src, mask->sctp_src);
sh->dest = OVS_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 int ovs_vport_output(struct net *net, struct sock *sk,
struct sk_buff *skb)
{
struct ovs_frag_data *data = this_cpu_ptr(&ovs_frag_data_storage);
struct vport *vport = data->vport;
if (skb_cow_head(skb, data->l2_len) < 0) {
kfree_skb(skb);
return -ENOMEM;
}
__skb_dst_copy(skb, data->dst);
*OVS_CB(skb) = data->cb;
skb->inner_protocol = data->inner_protocol;
if (data->vlan_tci & VLAN_CFI_MASK)
__vlan_hwaccel_put_tag(skb, data->vlan_proto, data->vlan_tci & ~VLAN_CFI_MASK);
else
__vlan_hwaccel_clear_tag(skb);
/* Reconstruct the MAC header. */
skb_push(skb, data->l2_len);
memcpy(skb->data, &data->l2_data, data->l2_len);
skb_postpush_rcsum(skb, skb->data, data->l2_len);
skb_reset_mac_header(skb);
if (eth_p_mpls(skb->protocol)) {
skb->inner_network_header = skb->network_header;
skb_set_network_header(skb, data->network_offset);
skb_reset_mac_len(skb);
}
ovs_vport_send(vport, skb, data->mac_proto);
return 0;
}
static unsigned int
ovs_dst_get_mtu(const struct dst_entry *dst)
{
return dst->dev->mtu;
}
static struct dst_ops ovs_dst_ops = {
.family = AF_UNSPEC,
.mtu = ovs_dst_get_mtu,
};
/* prepare_frag() is called once per (larger-than-MTU) frame; its inverse is
* ovs_vport_output(), which is called once per fragmented packet.
*/
static void prepare_frag(struct vport *vport, struct sk_buff *skb,
u16 orig_network_offset, u8 mac_proto)
{
unsigned int hlen = skb_network_offset(skb);
struct ovs_frag_data *data;
data = this_cpu_ptr(&ovs_frag_data_storage);
data->dst = skb->_skb_refdst;
data->vport = vport;
data->cb = *OVS_CB(skb);
data->inner_protocol = skb->inner_protocol;
data->network_offset = orig_network_offset;
if (skb_vlan_tag_present(skb))
data->vlan_tci = skb_vlan_tag_get(skb) | VLAN_CFI_MASK;
else
data->vlan_tci = 0;
data->vlan_proto = skb->vlan_proto;
data->mac_proto = mac_proto;
data->l2_len = hlen;
memcpy(&data->l2_data, skb->data, hlen);
memset(IPCB(skb), 0, sizeof(struct inet_skb_parm));
skb_pull(skb, hlen);
}
static void ovs_fragment(struct net *net, struct vport *vport,
struct sk_buff *skb, u16 mru,
struct sw_flow_key *key)
{
u16 orig_network_offset = 0;
if (eth_p_mpls(skb->protocol)) {
orig_network_offset = skb_network_offset(skb);
skb->network_header = skb->inner_network_header;
}
if (skb_network_offset(skb) > MAX_L2_LEN) {
OVS_NLERR(1, "L2 header too long to fragment");
goto err;
}
if (key->eth.type == htons(ETH_P_IP)) {
struct rtable ovs_rt = { 0 };
unsigned long orig_dst;
prepare_frag(vport, skb, orig_network_offset,
ovs_key_mac_proto(key));
dst_init(&ovs_rt.dst, &ovs_dst_ops, NULL, 1,
DST_OBSOLETE_NONE, DST_NOCOUNT);
ovs_rt.dst.dev = vport->dev;
orig_dst = skb->_skb_refdst;
skb_dst_set_noref(skb, &ovs_rt.dst);
IPCB(skb)->frag_max_size = mru;
ip_do_fragment(net, skb->sk, skb, ovs_vport_output);
refdst_drop(orig_dst);
} else if (key->eth.type == htons(ETH_P_IPV6)) {
unsigned long orig_dst;
struct rt6_info ovs_rt;
prepare_frag(vport, skb, orig_network_offset,
ovs_key_mac_proto(key));
memset(&ovs_rt, 0, sizeof(ovs_rt));
dst_init(&ovs_rt.dst, &ovs_dst_ops, NULL, 1,
DST_OBSOLETE_NONE, DST_NOCOUNT);
ovs_rt.dst.dev = vport->dev;
orig_dst = skb->_skb_refdst;
skb_dst_set_noref(skb, &ovs_rt.dst);
IP6CB(skb)->frag_max_size = mru;
ipv6_stub->ipv6_fragment(net, skb->sk, skb, ovs_vport_output);
refdst_drop(orig_dst);
} else {
WARN_ONCE(1, "Failed fragment ->%s: eth=%04x, MRU=%d, MTU=%d.",
ovs_vport_name(vport), ntohs(key->eth.type), mru,
vport->dev->mtu);
goto err;
}
return;
err:
kfree_skb(skb);
}
static void do_output(struct datapath *dp, struct sk_buff *skb, int out_port,
struct sw_flow_key *key)
{
struct vport *vport = ovs_vport_rcu(dp, out_port);
if (likely(vport)) {
u16 mru = OVS_CB(skb)->mru;
u32 cutlen = OVS_CB(skb)->cutlen;
if (unlikely(cutlen > 0)) {
if (skb->len - cutlen > ovs_mac_header_len(key))
pskb_trim(skb, skb->len - cutlen);
else
pskb_trim(skb, ovs_mac_header_len(key));
}
if (likely(!mru ||
(skb->len <= mru + vport->dev->hard_header_len))) {
ovs_vport_send(vport, skb, ovs_key_mac_proto(key));
} else if (mru <= vport->dev->mtu) {
struct net *net = read_pnet(&dp->net);
ovs_fragment(net, vport, skb, mru, key);
} else {
kfree_skb(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,
const struct nlattr *actions, int actions_len,
uint32_t cutlen)
{
struct dp_upcall_info upcall;
const struct nlattr *a;
int rem;
memset(&upcall, 0, sizeof(upcall));
upcall.cmd = OVS_PACKET_CMD_ACTION;
upcall.mru = OVS_CB(skb)->mru;
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:
if (dp->user_features &
OVS_DP_F_DISPATCH_UPCALL_PER_CPU)
upcall.portid =
ovs_dp_get_upcall_portid(dp,
smp_processor_id());
else
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 = dev_fill_metadata_dst(vport->dev, skb);
if (!err)
upcall.egress_tun_info = skb_tunnel_info(skb);
}
break;
}
case OVS_USERSPACE_ATTR_ACTIONS: {
/* Include actions. */
upcall.actions = actions;
upcall.actions_len = actions_len;
break;
}
} /* End of switch. */
}
return ovs_dp_upcall(dp, skb, key, &upcall, cutlen);
}
static int dec_ttl_exception_handler(struct datapath *dp, struct sk_buff *skb,
struct sw_flow_key *key,
const struct nlattr *attr)
{
/* The first attribute is always 'OVS_DEC_TTL_ATTR_ACTION'. */
struct nlattr *actions = nla_data(attr);
if (nla_len(actions))
return clone_execute(dp, skb, key, 0, nla_data(actions),
nla_len(actions), true, false);
consume_skb(skb);
return 0;
}
/* When 'last' is true, sample() should always consume the 'skb'.
* Otherwise, sample() should keep 'skb' intact regardless what
* actions are executed within sample().
*/
static int sample(struct datapath *dp, struct sk_buff *skb,
struct sw_flow_key *key, const struct nlattr *attr,
bool last)
{
struct nlattr *actions;
struct nlattr *sample_arg;
int rem = nla_len(attr);
const struct sample_arg *arg;
bool clone_flow_key;
/* The first action is always 'OVS_SAMPLE_ATTR_ARG'. */
sample_arg = nla_data(attr);
arg = nla_data(sample_arg);
actions = nla_next(sample_arg, &rem);
if ((arg->probability != U32_MAX) &&
(!arg->probability || prandom_u32() > arg->probability)) {
if (last)
consume_skb(skb);
return 0;
}
clone_flow_key = !arg->exec;
return clone_execute(dp, skb, key, 0, actions, rem, last,
clone_flow_key);
}
/* When 'last' is true, clone() should always consume the 'skb'.
* Otherwise, clone() should keep 'skb' intact regardless what
* actions are executed within clone().
*/
static int clone(struct datapath *dp, struct sk_buff *skb,
struct sw_flow_key *key, const struct nlattr *attr,
bool last)
{
struct nlattr *actions;
struct nlattr *clone_arg;
int rem = nla_len(attr);
bool dont_clone_flow_key;
/* The first action is always 'OVS_CLONE_ATTR_ARG'. */
clone_arg = nla_data(attr);
dont_clone_flow_key = nla_get_u32(clone_arg);
actions = nla_next(clone_arg, &rem);
return clone_execute(dp, skb, key, 0, actions, rem, last,
!dont_clone_flow_key);
}
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) {
struct ovs_tunnel_info *tun = nla_data(a);
skb_dst_drop(skb);
dst_hold((struct dst_entry *)tun->tun_dst);
skb_dst_set(skb, (struct dst_entry *)tun->tun_dst);
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:
OVS_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:
OVS_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_NSH:
err = set_nsh(skb, flow_key, a);
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;
case OVS_KEY_ATTR_CT_STATE:
case OVS_KEY_ATTR_CT_ZONE:
case OVS_KEY_ATTR_CT_MARK:
case OVS_KEY_ATTR_CT_LABELS:
case OVS_KEY_ATTR_CT_ORIG_TUPLE_IPV4:
case OVS_KEY_ATTR_CT_ORIG_TUPLE_IPV6:
err = -EINVAL;
break;
}
return err;
}
static int execute_recirc(struct datapath *dp, struct sk_buff *skb,
struct sw_flow_key *key,
const struct nlattr *a, bool last)
{
u32 recirc_id;
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));
recirc_id = nla_get_u32(a);
return clone_execute(dp, skb, key, recirc_id, NULL, 0, last, true);
}
static int execute_check_pkt_len(struct datapath *dp, struct sk_buff *skb,
struct sw_flow_key *key,
const struct nlattr *attr, bool last)
{
struct ovs_skb_cb *ovs_cb = OVS_CB(skb);
const struct nlattr *actions, *cpl_arg;
int len, max_len, rem = nla_len(attr);
const struct check_pkt_len_arg *arg;
bool clone_flow_key;
/* The first netlink attribute in 'attr' is always
* 'OVS_CHECK_PKT_LEN_ATTR_ARG'.
*/
cpl_arg = nla_data(attr);
arg = nla_data(cpl_arg);
len = ovs_cb->mru ? ovs_cb->mru + skb->mac_len : skb->len;
max_len = arg->pkt_len;
if ((skb_is_gso(skb) && skb_gso_validate_mac_len(skb, max_len)) ||
len <= max_len) {
/* Second netlink attribute in 'attr' is always
* 'OVS_CHECK_PKT_LEN_ATTR_ACTIONS_IF_LESS_EQUAL'.
*/
actions = nla_next(cpl_arg, &rem);
clone_flow_key = !arg->exec_for_lesser_equal;
} else {
/* Third netlink attribute in 'attr' is always
* 'OVS_CHECK_PKT_LEN_ATTR_ACTIONS_IF_GREATER'.
*/
actions = nla_next(cpl_arg, &rem);
actions = nla_next(actions, &rem);
clone_flow_key = !arg->exec_for_greater;
}
return clone_execute(dp, skb, key, 0, nla_data(actions),
nla_len(actions), last, clone_flow_key);
}
static int execute_dec_ttl(struct sk_buff *skb, struct sw_flow_key *key)
{
int err;
if (skb->protocol == htons(ETH_P_IPV6)) {
struct ipv6hdr *nh;
err = skb_ensure_writable(skb, skb_network_offset(skb) +
sizeof(*nh));
if (unlikely(err))
return err;
nh = ipv6_hdr(skb);
if (nh->hop_limit <= 1)
return -EHOSTUNREACH;
key->ip.ttl = --nh->hop_limit;
} else if (skb->protocol == htons(ETH_P_IP)) {
struct iphdr *nh;
u8 old_ttl;
err = skb_ensure_writable(skb, skb_network_offset(skb) +
sizeof(*nh));
if (unlikely(err))
return err;
nh = ip_hdr(skb);
if (nh->ttl <= 1)
return -EHOSTUNREACH;
old_ttl = nh->ttl--;
csum_replace2(&nh->check, htons(old_ttl << 8),
htons(nh->ttl << 8));
key->ip.ttl = nh->ttl;
}
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)
{
const struct nlattr *a;
int rem;
for (a = attr, rem = len; rem > 0;
a = nla_next(a, &rem)) {
int err = 0;
if (trace_ovs_do_execute_action_enabled())
trace_ovs_do_execute_action(dp, skb, key, a, rem);
switch (nla_type(a)) {
case OVS_ACTION_ATTR_OUTPUT: {
int port = nla_get_u32(a);
struct sk_buff *clone;
/* Every output action needs a separate clone
* of 'skb', In case the output action is the
* last action, cloning can be avoided.
*/
if (nla_is_last(a, rem)) {
do_output(dp, skb, port, key);
/* 'skb' has been used for output.
*/
return 0;
}
clone = skb_clone(skb, GFP_ATOMIC);
if (clone)
do_output(dp, clone, port, key);
OVS_CB(skb)->cutlen = 0;
break;
}
case OVS_ACTION_ATTR_TRUNC: {
struct ovs_action_trunc *trunc = nla_data(a);
if (skb->len > trunc->max_len)
OVS_CB(skb)->cutlen = skb->len - trunc->max_len;
break;
}
case OVS_ACTION_ATTR_USERSPACE:
output_userspace(dp, skb, key, a, attr,
len, OVS_CB(skb)->cutlen);
OVS_CB(skb)->cutlen = 0;
break;
case OVS_ACTION_ATTR_HASH:
execute_hash(skb, key, a);
break;
case OVS_ACTION_ATTR_PUSH_MPLS: {
struct ovs_action_push_mpls *mpls = nla_data(a);
err = push_mpls(skb, key, mpls->mpls_lse,
mpls->mpls_ethertype, skb->mac_len);
break;
}
case OVS_ACTION_ATTR_ADD_MPLS: {
struct ovs_action_add_mpls *mpls = nla_data(a);
__u16 mac_len = 0;
if (mpls->tun_flags & OVS_MPLS_L3_TUNNEL_FLAG_MASK)
mac_len = skb->mac_len;
err = push_mpls(skb, key, mpls->mpls_lse,
mpls->mpls_ethertype, mac_len);
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: {
bool last = nla_is_last(a, rem);
err = execute_recirc(dp, skb, key, a, last);
if (last) {
/* 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: {
bool last = nla_is_last(a, rem);
err = sample(dp, skb, key, a, last);
if (last)
return err;
break;
}
case OVS_ACTION_ATTR_CT:
if (!is_flow_key_valid(key)) {
err = ovs_flow_key_update(skb, key);
if (err)
return err;
}
err = ovs_ct_execute(ovs_dp_get_net(dp), skb, key,
nla_data(a));
/* Hide stolen IP fragments from user space. */
if (err)
return err == -EINPROGRESS ? 0 : err;
break;
case OVS_ACTION_ATTR_CT_CLEAR:
err = ovs_ct_clear(skb, key);
break;
case OVS_ACTION_ATTR_PUSH_ETH:
err = push_eth(skb, key, nla_data(a));
break;
case OVS_ACTION_ATTR_POP_ETH:
err = pop_eth(skb, key);
break;
case OVS_ACTION_ATTR_PUSH_NSH: {
u8 buffer[NSH_HDR_MAX_LEN];
struct nshhdr *nh = (struct nshhdr *)buffer;
err = nsh_hdr_from_nlattr(nla_data(a), nh,
NSH_HDR_MAX_LEN);
if (unlikely(err))
break;
err = push_nsh(skb, key, nh);
break;
}
case OVS_ACTION_ATTR_POP_NSH:
err = pop_nsh(skb, key);
break;
case OVS_ACTION_ATTR_METER:
if (ovs_meter_execute(dp, skb, key, nla_get_u32(a))) {
consume_skb(skb);
return 0;
}
break;
case OVS_ACTION_ATTR_CLONE: {
bool last = nla_is_last(a, rem);
err = clone(dp, skb, key, a, last);
if (last)
return err;
break;
}
case OVS_ACTION_ATTR_CHECK_PKT_LEN: {
bool last = nla_is_last(a, rem);
err = execute_check_pkt_len(dp, skb, key, a, last);
if (last)
return err;
break;
}
case OVS_ACTION_ATTR_DEC_TTL:
err = execute_dec_ttl(skb, key);
if (err == -EHOSTUNREACH)
return dec_ttl_exception_handler(dp, skb,
key, a);
break;
}
if (unlikely(err)) {
kfree_skb(skb);
return err;
}
}
consume_skb(skb);
return 0;
}
/* Execute the actions on the clone of the packet. The effect of the
* execution does not affect the original 'skb' nor the original 'key'.
*
* The execution may be deferred in case the actions can not be executed
* immediately.
*/
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)
{
struct deferred_action *da;
struct sw_flow_key *clone;
skb = last ? skb : skb_clone(skb, GFP_ATOMIC);
if (!skb) {
/* Out of memory, skip this action.
*/
return 0;
}
/* When clone_flow_key is false, the 'key' will not be change
* by the actions, then the 'key' can be used directly.
* Otherwise, try to clone key from the next recursion level of
* 'flow_keys'. If clone is successful, execute the actions
* without deferring.
*/
clone = clone_flow_key ? clone_key(key) : key;
if (clone) {
int err = 0;
if (actions) { /* Sample action */
if (clone_flow_key)
__this_cpu_inc(exec_actions_level);
err = do_execute_actions(dp, skb, clone,
actions, len);
if (clone_flow_key)
__this_cpu_dec(exec_actions_level);
} else { /* Recirc action */
clone->recirc_id = recirc_id;
ovs_dp_process_packet(skb, clone);
}
return err;
}
/* Out of 'flow_keys' space. Defer actions */
da = add_deferred_actions(skb, key, actions, len);
if (da) {
if (!actions) { /* Recirc action */
key = &da->pkt_key;
key->recirc_id = recirc_id;
}
} else {
/* Out of per CPU action FIFO space. Drop the 'skb' and
* log an error.
*/
kfree_skb(skb);
if (net_ratelimit()) {
if (actions) { /* Sample action */
pr_warn("%s: deferred action limit reached, drop sample action\n",
ovs_dp_name(dp));
} else { /* Recirc action */
pr_warn("%s: deferred action limit reached, drop recirc action\n",
ovs_dp_name(dp));
}
}
}
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;
int actions_len = da->actions_len;
if (actions)
do_execute_actions(dp, skb, key, actions, actions_len);
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 err, level;
level = __this_cpu_inc_return(exec_actions_level);
if (unlikely(level > OVS_RECURSION_LIMIT)) {
net_crit_ratelimited("ovs: recursion limit reached on datapath %s, probable configuration error\n",
ovs_dp_name(dp));
kfree_skb(skb);
err = -ENETDOWN;
goto out;
}
OVS_CB(skb)->acts_origlen = acts->orig_len;
err = do_execute_actions(dp, skb, key,
acts->actions, acts->actions_len);
if (level == 1)
process_deferred_actions(dp);
out:
__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;
flow_keys = alloc_percpu(struct action_flow_keys);
if (!flow_keys) {
free_percpu(action_fifos);
return -ENOMEM;
}
return 0;
}
void action_fifos_exit(void)
{
free_percpu(action_fifos);
free_percpu(flow_keys);
}