linux/net/openvswitch/flow.c
Ben Pfaff 24cc59d1eb openvswitch: Consistently include VLAN header in flow and port stats.
Until now, when VLAN acceleration was in use, the bytes of the VLAN header
were not included in port or flow byte counters.  They were however
included when VLAN acceleration was not used.  This commit corrects the
inconsistency, by always including the VLAN header in byte counters.

Previous discussion at
http://openvswitch.org/pipermail/dev/2014-December/049521.html

Reported-by: Motonori Shindo <mshindo@vmware.com>
Signed-off-by: Ben Pfaff <blp@nicira.com>
Reviewed-by: Flavio Leitner <fbl@sysclose.org>
Acked-by: Pravin B Shelar <pshelar@nicira.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-01-02 16:14:20 -05:00

727 lines
19 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
*/
#include <linux/uaccess.h>
#include <linux/netdevice.h>
#include <linux/etherdevice.h>
#include <linux/if_ether.h>
#include <linux/if_vlan.h>
#include <net/llc_pdu.h>
#include <linux/kernel.h>
#include <linux/jhash.h>
#include <linux/jiffies.h>
#include <linux/llc.h>
#include <linux/module.h>
#include <linux/in.h>
#include <linux/rcupdate.h>
#include <linux/if_arp.h>
#include <linux/ip.h>
#include <linux/ipv6.h>
#include <linux/mpls.h>
#include <linux/sctp.h>
#include <linux/smp.h>
#include <linux/tcp.h>
#include <linux/udp.h>
#include <linux/icmp.h>
#include <linux/icmpv6.h>
#include <linux/rculist.h>
#include <net/ip.h>
#include <net/ip_tunnels.h>
#include <net/ipv6.h>
#include <net/mpls.h>
#include <net/ndisc.h>
#include "datapath.h"
#include "flow.h"
#include "flow_netlink.h"
u64 ovs_flow_used_time(unsigned long flow_jiffies)
{
struct timespec cur_ts;
u64 cur_ms, idle_ms;
ktime_get_ts(&cur_ts);
idle_ms = jiffies_to_msecs(jiffies - flow_jiffies);
cur_ms = (u64)cur_ts.tv_sec * MSEC_PER_SEC +
cur_ts.tv_nsec / NSEC_PER_MSEC;
return cur_ms - idle_ms;
}
#define TCP_FLAGS_BE16(tp) (*(__be16 *)&tcp_flag_word(tp) & htons(0x0FFF))
void ovs_flow_stats_update(struct sw_flow *flow, __be16 tcp_flags,
const struct sk_buff *skb)
{
struct flow_stats *stats;
int node = numa_node_id();
int len = skb->len + (vlan_tx_tag_present(skb) ? VLAN_HLEN : 0);
stats = rcu_dereference(flow->stats[node]);
/* Check if already have node-specific stats. */
if (likely(stats)) {
spin_lock(&stats->lock);
/* Mark if we write on the pre-allocated stats. */
if (node == 0 && unlikely(flow->stats_last_writer != node))
flow->stats_last_writer = node;
} else {
stats = rcu_dereference(flow->stats[0]); /* Pre-allocated. */
spin_lock(&stats->lock);
/* If the current NUMA-node is the only writer on the
* pre-allocated stats keep using them.
*/
if (unlikely(flow->stats_last_writer != node)) {
/* A previous locker may have already allocated the
* stats, so we need to check again. If node-specific
* stats were already allocated, we update the pre-
* allocated stats as we have already locked them.
*/
if (likely(flow->stats_last_writer != NUMA_NO_NODE)
&& likely(!rcu_access_pointer(flow->stats[node]))) {
/* Try to allocate node-specific stats. */
struct flow_stats *new_stats;
new_stats =
kmem_cache_alloc_node(flow_stats_cache,
GFP_THISNODE |
__GFP_NOMEMALLOC,
node);
if (likely(new_stats)) {
new_stats->used = jiffies;
new_stats->packet_count = 1;
new_stats->byte_count = len;
new_stats->tcp_flags = tcp_flags;
spin_lock_init(&new_stats->lock);
rcu_assign_pointer(flow->stats[node],
new_stats);
goto unlock;
}
}
flow->stats_last_writer = node;
}
}
stats->used = jiffies;
stats->packet_count++;
stats->byte_count += len;
stats->tcp_flags |= tcp_flags;
unlock:
spin_unlock(&stats->lock);
}
/* Must be called with rcu_read_lock or ovs_mutex. */
void ovs_flow_stats_get(const struct sw_flow *flow,
struct ovs_flow_stats *ovs_stats,
unsigned long *used, __be16 *tcp_flags)
{
int node;
*used = 0;
*tcp_flags = 0;
memset(ovs_stats, 0, sizeof(*ovs_stats));
for_each_node(node) {
struct flow_stats *stats = rcu_dereference_ovsl(flow->stats[node]);
if (stats) {
/* Local CPU may write on non-local stats, so we must
* block bottom-halves here.
*/
spin_lock_bh(&stats->lock);
if (!*used || time_after(stats->used, *used))
*used = stats->used;
*tcp_flags |= stats->tcp_flags;
ovs_stats->n_packets += stats->packet_count;
ovs_stats->n_bytes += stats->byte_count;
spin_unlock_bh(&stats->lock);
}
}
}
/* Called with ovs_mutex. */
void ovs_flow_stats_clear(struct sw_flow *flow)
{
int node;
for_each_node(node) {
struct flow_stats *stats = ovsl_dereference(flow->stats[node]);
if (stats) {
spin_lock_bh(&stats->lock);
stats->used = 0;
stats->packet_count = 0;
stats->byte_count = 0;
stats->tcp_flags = 0;
spin_unlock_bh(&stats->lock);
}
}
}
static int check_header(struct sk_buff *skb, int len)
{
if (unlikely(skb->len < len))
return -EINVAL;
if (unlikely(!pskb_may_pull(skb, len)))
return -ENOMEM;
return 0;
}
static bool arphdr_ok(struct sk_buff *skb)
{
return pskb_may_pull(skb, skb_network_offset(skb) +
sizeof(struct arp_eth_header));
}
static int check_iphdr(struct sk_buff *skb)
{
unsigned int nh_ofs = skb_network_offset(skb);
unsigned int ip_len;
int err;
err = check_header(skb, nh_ofs + sizeof(struct iphdr));
if (unlikely(err))
return err;
ip_len = ip_hdrlen(skb);
if (unlikely(ip_len < sizeof(struct iphdr) ||
skb->len < nh_ofs + ip_len))
return -EINVAL;
skb_set_transport_header(skb, nh_ofs + ip_len);
return 0;
}
static bool tcphdr_ok(struct sk_buff *skb)
{
int th_ofs = skb_transport_offset(skb);
int tcp_len;
if (unlikely(!pskb_may_pull(skb, th_ofs + sizeof(struct tcphdr))))
return false;
tcp_len = tcp_hdrlen(skb);
if (unlikely(tcp_len < sizeof(struct tcphdr) ||
skb->len < th_ofs + tcp_len))
return false;
return true;
}
static bool udphdr_ok(struct sk_buff *skb)
{
return pskb_may_pull(skb, skb_transport_offset(skb) +
sizeof(struct udphdr));
}
static bool sctphdr_ok(struct sk_buff *skb)
{
return pskb_may_pull(skb, skb_transport_offset(skb) +
sizeof(struct sctphdr));
}
static bool icmphdr_ok(struct sk_buff *skb)
{
return pskb_may_pull(skb, skb_transport_offset(skb) +
sizeof(struct icmphdr));
}
static int parse_ipv6hdr(struct sk_buff *skb, struct sw_flow_key *key)
{
unsigned int nh_ofs = skb_network_offset(skb);
unsigned int nh_len;
int payload_ofs;
struct ipv6hdr *nh;
uint8_t nexthdr;
__be16 frag_off;
int err;
err = check_header(skb, nh_ofs + sizeof(*nh));
if (unlikely(err))
return err;
nh = ipv6_hdr(skb);
nexthdr = nh->nexthdr;
payload_ofs = (u8 *)(nh + 1) - skb->data;
key->ip.proto = NEXTHDR_NONE;
key->ip.tos = ipv6_get_dsfield(nh);
key->ip.ttl = nh->hop_limit;
key->ipv6.label = *(__be32 *)nh & htonl(IPV6_FLOWINFO_FLOWLABEL);
key->ipv6.addr.src = nh->saddr;
key->ipv6.addr.dst = nh->daddr;
payload_ofs = ipv6_skip_exthdr(skb, payload_ofs, &nexthdr, &frag_off);
if (unlikely(payload_ofs < 0))
return -EINVAL;
if (frag_off) {
if (frag_off & htons(~0x7))
key->ip.frag = OVS_FRAG_TYPE_LATER;
else
key->ip.frag = OVS_FRAG_TYPE_FIRST;
} else {
key->ip.frag = OVS_FRAG_TYPE_NONE;
}
nh_len = payload_ofs - nh_ofs;
skb_set_transport_header(skb, nh_ofs + nh_len);
key->ip.proto = nexthdr;
return nh_len;
}
static bool icmp6hdr_ok(struct sk_buff *skb)
{
return pskb_may_pull(skb, skb_transport_offset(skb) +
sizeof(struct icmp6hdr));
}
static int parse_vlan(struct sk_buff *skb, struct sw_flow_key *key)
{
struct qtag_prefix {
__be16 eth_type; /* ETH_P_8021Q */
__be16 tci;
};
struct qtag_prefix *qp;
if (unlikely(skb->len < sizeof(struct qtag_prefix) + sizeof(__be16)))
return 0;
if (unlikely(!pskb_may_pull(skb, sizeof(struct qtag_prefix) +
sizeof(__be16))))
return -ENOMEM;
qp = (struct qtag_prefix *) skb->data;
key->eth.tci = qp->tci | htons(VLAN_TAG_PRESENT);
__skb_pull(skb, sizeof(struct qtag_prefix));
return 0;
}
static __be16 parse_ethertype(struct sk_buff *skb)
{
struct llc_snap_hdr {
u8 dsap; /* Always 0xAA */
u8 ssap; /* Always 0xAA */
u8 ctrl;
u8 oui[3];
__be16 ethertype;
};
struct llc_snap_hdr *llc;
__be16 proto;
proto = *(__be16 *) skb->data;
__skb_pull(skb, sizeof(__be16));
if (ntohs(proto) >= ETH_P_802_3_MIN)
return proto;
if (skb->len < sizeof(struct llc_snap_hdr))
return htons(ETH_P_802_2);
if (unlikely(!pskb_may_pull(skb, sizeof(struct llc_snap_hdr))))
return htons(0);
llc = (struct llc_snap_hdr *) skb->data;
if (llc->dsap != LLC_SAP_SNAP ||
llc->ssap != LLC_SAP_SNAP ||
(llc->oui[0] | llc->oui[1] | llc->oui[2]) != 0)
return htons(ETH_P_802_2);
__skb_pull(skb, sizeof(struct llc_snap_hdr));
if (ntohs(llc->ethertype) >= ETH_P_802_3_MIN)
return llc->ethertype;
return htons(ETH_P_802_2);
}
static int parse_icmpv6(struct sk_buff *skb, struct sw_flow_key *key,
int nh_len)
{
struct icmp6hdr *icmp = icmp6_hdr(skb);
/* The ICMPv6 type and code fields use the 16-bit transport port
* fields, so we need to store them in 16-bit network byte order.
*/
key->tp.src = htons(icmp->icmp6_type);
key->tp.dst = htons(icmp->icmp6_code);
memset(&key->ipv6.nd, 0, sizeof(key->ipv6.nd));
if (icmp->icmp6_code == 0 &&
(icmp->icmp6_type == NDISC_NEIGHBOUR_SOLICITATION ||
icmp->icmp6_type == NDISC_NEIGHBOUR_ADVERTISEMENT)) {
int icmp_len = skb->len - skb_transport_offset(skb);
struct nd_msg *nd;
int offset;
/* In order to process neighbor discovery options, we need the
* entire packet.
*/
if (unlikely(icmp_len < sizeof(*nd)))
return 0;
if (unlikely(skb_linearize(skb)))
return -ENOMEM;
nd = (struct nd_msg *)skb_transport_header(skb);
key->ipv6.nd.target = nd->target;
icmp_len -= sizeof(*nd);
offset = 0;
while (icmp_len >= 8) {
struct nd_opt_hdr *nd_opt =
(struct nd_opt_hdr *)(nd->opt + offset);
int opt_len = nd_opt->nd_opt_len * 8;
if (unlikely(!opt_len || opt_len > icmp_len))
return 0;
/* Store the link layer address if the appropriate
* option is provided. It is considered an error if
* the same link layer option is specified twice.
*/
if (nd_opt->nd_opt_type == ND_OPT_SOURCE_LL_ADDR
&& opt_len == 8) {
if (unlikely(!is_zero_ether_addr(key->ipv6.nd.sll)))
goto invalid;
ether_addr_copy(key->ipv6.nd.sll,
&nd->opt[offset+sizeof(*nd_opt)]);
} else if (nd_opt->nd_opt_type == ND_OPT_TARGET_LL_ADDR
&& opt_len == 8) {
if (unlikely(!is_zero_ether_addr(key->ipv6.nd.tll)))
goto invalid;
ether_addr_copy(key->ipv6.nd.tll,
&nd->opt[offset+sizeof(*nd_opt)]);
}
icmp_len -= opt_len;
offset += opt_len;
}
}
return 0;
invalid:
memset(&key->ipv6.nd.target, 0, sizeof(key->ipv6.nd.target));
memset(key->ipv6.nd.sll, 0, sizeof(key->ipv6.nd.sll));
memset(key->ipv6.nd.tll, 0, sizeof(key->ipv6.nd.tll));
return 0;
}
/**
* key_extract - extracts a flow key from an Ethernet frame.
* @skb: sk_buff that contains the frame, with skb->data pointing to the
* Ethernet header
* @key: output flow key
*
* The caller must ensure that skb->len >= ETH_HLEN.
*
* Returns 0 if successful, otherwise a negative errno value.
*
* Initializes @skb header pointers as follows:
*
* - skb->mac_header: the Ethernet header.
*
* - skb->network_header: just past the Ethernet header, or just past the
* VLAN header, to the first byte of the Ethernet payload.
*
* - skb->transport_header: If key->eth.type is ETH_P_IP or ETH_P_IPV6
* on output, then just past the IP header, if one is present and
* of a correct length, otherwise the same as skb->network_header.
* For other key->eth.type values it is left untouched.
*/
static int key_extract(struct sk_buff *skb, struct sw_flow_key *key)
{
int error;
struct ethhdr *eth;
/* Flags are always used as part of stats */
key->tp.flags = 0;
skb_reset_mac_header(skb);
/* Link layer. We are guaranteed to have at least the 14 byte Ethernet
* header in the linear data area.
*/
eth = eth_hdr(skb);
ether_addr_copy(key->eth.src, eth->h_source);
ether_addr_copy(key->eth.dst, eth->h_dest);
__skb_pull(skb, 2 * ETH_ALEN);
/* We are going to push all headers that we pull, so no need to
* update skb->csum here.
*/
key->eth.tci = 0;
if (vlan_tx_tag_present(skb))
key->eth.tci = htons(skb->vlan_tci);
else if (eth->h_proto == htons(ETH_P_8021Q))
if (unlikely(parse_vlan(skb, key)))
return -ENOMEM;
key->eth.type = parse_ethertype(skb);
if (unlikely(key->eth.type == htons(0)))
return -ENOMEM;
skb_reset_network_header(skb);
skb_reset_mac_len(skb);
__skb_push(skb, skb->data - skb_mac_header(skb));
/* Network layer. */
if (key->eth.type == htons(ETH_P_IP)) {
struct iphdr *nh;
__be16 offset;
error = check_iphdr(skb);
if (unlikely(error)) {
memset(&key->ip, 0, sizeof(key->ip));
memset(&key->ipv4, 0, sizeof(key->ipv4));
if (error == -EINVAL) {
skb->transport_header = skb->network_header;
error = 0;
}
return error;
}
nh = ip_hdr(skb);
key->ipv4.addr.src = nh->saddr;
key->ipv4.addr.dst = nh->daddr;
key->ip.proto = nh->protocol;
key->ip.tos = nh->tos;
key->ip.ttl = nh->ttl;
offset = nh->frag_off & htons(IP_OFFSET);
if (offset) {
key->ip.frag = OVS_FRAG_TYPE_LATER;
return 0;
}
if (nh->frag_off & htons(IP_MF) ||
skb_shinfo(skb)->gso_type & SKB_GSO_UDP)
key->ip.frag = OVS_FRAG_TYPE_FIRST;
else
key->ip.frag = OVS_FRAG_TYPE_NONE;
/* Transport layer. */
if (key->ip.proto == IPPROTO_TCP) {
if (tcphdr_ok(skb)) {
struct tcphdr *tcp = tcp_hdr(skb);
key->tp.src = tcp->source;
key->tp.dst = tcp->dest;
key->tp.flags = TCP_FLAGS_BE16(tcp);
} else {
memset(&key->tp, 0, sizeof(key->tp));
}
} else if (key->ip.proto == IPPROTO_UDP) {
if (udphdr_ok(skb)) {
struct udphdr *udp = udp_hdr(skb);
key->tp.src = udp->source;
key->tp.dst = udp->dest;
} else {
memset(&key->tp, 0, sizeof(key->tp));
}
} else if (key->ip.proto == IPPROTO_SCTP) {
if (sctphdr_ok(skb)) {
struct sctphdr *sctp = sctp_hdr(skb);
key->tp.src = sctp->source;
key->tp.dst = sctp->dest;
} else {
memset(&key->tp, 0, sizeof(key->tp));
}
} else if (key->ip.proto == IPPROTO_ICMP) {
if (icmphdr_ok(skb)) {
struct icmphdr *icmp = icmp_hdr(skb);
/* The ICMP type and code fields use the 16-bit
* transport port fields, so we need to store
* them in 16-bit network byte order. */
key->tp.src = htons(icmp->type);
key->tp.dst = htons(icmp->code);
} else {
memset(&key->tp, 0, sizeof(key->tp));
}
}
} else if (key->eth.type == htons(ETH_P_ARP) ||
key->eth.type == htons(ETH_P_RARP)) {
struct arp_eth_header *arp;
bool arp_available = arphdr_ok(skb);
arp = (struct arp_eth_header *)skb_network_header(skb);
if (arp_available &&
arp->ar_hrd == htons(ARPHRD_ETHER) &&
arp->ar_pro == htons(ETH_P_IP) &&
arp->ar_hln == ETH_ALEN &&
arp->ar_pln == 4) {
/* We only match on the lower 8 bits of the opcode. */
if (ntohs(arp->ar_op) <= 0xff)
key->ip.proto = ntohs(arp->ar_op);
else
key->ip.proto = 0;
memcpy(&key->ipv4.addr.src, arp->ar_sip, sizeof(key->ipv4.addr.src));
memcpy(&key->ipv4.addr.dst, arp->ar_tip, sizeof(key->ipv4.addr.dst));
ether_addr_copy(key->ipv4.arp.sha, arp->ar_sha);
ether_addr_copy(key->ipv4.arp.tha, arp->ar_tha);
} else {
memset(&key->ip, 0, sizeof(key->ip));
memset(&key->ipv4, 0, sizeof(key->ipv4));
}
} else if (eth_p_mpls(key->eth.type)) {
size_t stack_len = MPLS_HLEN;
/* In the presence of an MPLS label stack the end of the L2
* header and the beginning of the L3 header differ.
*
* Advance network_header to the beginning of the L3
* header. mac_len corresponds to the end of the L2 header.
*/
while (1) {
__be32 lse;
error = check_header(skb, skb->mac_len + stack_len);
if (unlikely(error))
return 0;
memcpy(&lse, skb_network_header(skb), MPLS_HLEN);
if (stack_len == MPLS_HLEN)
memcpy(&key->mpls.top_lse, &lse, MPLS_HLEN);
skb_set_network_header(skb, skb->mac_len + stack_len);
if (lse & htonl(MPLS_LS_S_MASK))
break;
stack_len += MPLS_HLEN;
}
} else if (key->eth.type == htons(ETH_P_IPV6)) {
int nh_len; /* IPv6 Header + Extensions */
nh_len = parse_ipv6hdr(skb, key);
if (unlikely(nh_len < 0)) {
memset(&key->ip, 0, sizeof(key->ip));
memset(&key->ipv6.addr, 0, sizeof(key->ipv6.addr));
if (nh_len == -EINVAL) {
skb->transport_header = skb->network_header;
error = 0;
} else {
error = nh_len;
}
return error;
}
if (key->ip.frag == OVS_FRAG_TYPE_LATER)
return 0;
if (skb_shinfo(skb)->gso_type & SKB_GSO_UDP)
key->ip.frag = OVS_FRAG_TYPE_FIRST;
/* Transport layer. */
if (key->ip.proto == NEXTHDR_TCP) {
if (tcphdr_ok(skb)) {
struct tcphdr *tcp = tcp_hdr(skb);
key->tp.src = tcp->source;
key->tp.dst = tcp->dest;
key->tp.flags = TCP_FLAGS_BE16(tcp);
} else {
memset(&key->tp, 0, sizeof(key->tp));
}
} else if (key->ip.proto == NEXTHDR_UDP) {
if (udphdr_ok(skb)) {
struct udphdr *udp = udp_hdr(skb);
key->tp.src = udp->source;
key->tp.dst = udp->dest;
} else {
memset(&key->tp, 0, sizeof(key->tp));
}
} else if (key->ip.proto == NEXTHDR_SCTP) {
if (sctphdr_ok(skb)) {
struct sctphdr *sctp = sctp_hdr(skb);
key->tp.src = sctp->source;
key->tp.dst = sctp->dest;
} else {
memset(&key->tp, 0, sizeof(key->tp));
}
} else if (key->ip.proto == NEXTHDR_ICMP) {
if (icmp6hdr_ok(skb)) {
error = parse_icmpv6(skb, key, nh_len);
if (error)
return error;
} else {
memset(&key->tp, 0, sizeof(key->tp));
}
}
}
return 0;
}
int ovs_flow_key_update(struct sk_buff *skb, struct sw_flow_key *key)
{
return key_extract(skb, key);
}
int ovs_flow_key_extract(const struct ovs_tunnel_info *tun_info,
struct sk_buff *skb, struct sw_flow_key *key)
{
/* Extract metadata from packet. */
if (tun_info) {
memcpy(&key->tun_key, &tun_info->tunnel, sizeof(key->tun_key));
if (tun_info->options) {
BUILD_BUG_ON((1 << (sizeof(tun_info->options_len) *
8)) - 1
> sizeof(key->tun_opts));
memcpy(GENEVE_OPTS(key, tun_info->options_len),
tun_info->options, tun_info->options_len);
key->tun_opts_len = tun_info->options_len;
} else {
key->tun_opts_len = 0;
}
} else {
key->tun_opts_len = 0;
memset(&key->tun_key, 0, sizeof(key->tun_key));
}
key->phy.priority = skb->priority;
key->phy.in_port = OVS_CB(skb)->input_vport->port_no;
key->phy.skb_mark = skb->mark;
key->ovs_flow_hash = 0;
key->recirc_id = 0;
return key_extract(skb, key);
}
int ovs_flow_key_extract_userspace(const struct nlattr *attr,
struct sk_buff *skb,
struct sw_flow_key *key, bool log)
{
int err;
/* Extract metadata from netlink attributes. */
err = ovs_nla_get_flow_metadata(attr, key, log);
if (err)
return err;
return key_extract(skb, key);
}