linux/net/openvswitch/flow.c
Jarno Rajahalme 9dd7f8907c openvswitch: Add original direction conntrack tuple to sw_flow_key.
Add the fields of the conntrack original direction 5-tuple to struct
sw_flow_key.  The new fields are initially marked as non-existent, and
are populated whenever a conntrack action is executed and either finds
or generates a conntrack entry.  This means that these fields exist
for all packets that were not rejected by conntrack as untrackable.

The original tuple fields in the sw_flow_key are filled from the
original direction tuple of the conntrack entry relating to the
current packet, or from the original direction tuple of the master
conntrack entry, if the current conntrack entry has a master.
Generally, expected connections of connections having an assigned
helper (e.g., FTP), have a master conntrack entry.

The main purpose of the new conntrack original tuple fields is to
allow matching on them for policy decision purposes, with the premise
that the admissibility of tracked connections reply packets (as well
as original direction packets), and both direction packets of any
related connections may be based on ACL rules applying to the master
connection's original direction 5-tuple.  This also makes it easier to
make policy decisions when the actual packet headers might have been
transformed by NAT, as the original direction 5-tuple represents the
packet headers before any such transformation.

When using the original direction 5-tuple the admissibility of return
and/or related packets need not be based on the mere existence of a
conntrack entry, allowing separation of admission policy from the
established conntrack state.  While existence of a conntrack entry is
required for admission of the return or related packets, policy
changes can render connections that were initially admitted to be
rejected or dropped afterwards.  If the admission of the return and
related packets was based on mere conntrack state (e.g., connection
being in an established state), a policy change that would make the
connection rejected or dropped would need to find and delete all
conntrack entries affected by such a change.  When using the original
direction 5-tuple matching the affected conntrack entries can be
allowed to time out instead, as the established state of the
connection would not need to be the basis for packet admission any
more.

It should be noted that the directionality of related connections may
be the same or different than that of the master connection, and
neither the original direction 5-tuple nor the conntrack state bits
carry this information.  If needed, the directionality of the master
connection can be stored in master's conntrack mark or labels, which
are automatically inherited by the expected related connections.

The fact that neither ARP nor ND packets are trackable by conntrack
allows mutual exclusion between ARP/ND and the new conntrack original
tuple fields.  Hence, the IP addresses are overlaid in union with ARP
and ND fields.  This allows the sw_flow_key to not grow much due to
this patch, but it also means that we must be careful to never use the
new key fields with ARP or ND packets.  ARP is easy to distinguish and
keep mutually exclusive based on the ethernet type, but ND being an
ICMPv6 protocol requires a bit more attention.

Signed-off-by: Jarno Rajahalme <jarno@ovn.org>
Acked-by: Joe Stringer <joe@ovn.org>
Acked-by: Pravin B Shelar <pshelar@ovn.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-02-09 22:59:34 -05:00

853 lines
22 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/cpumask.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 "conntrack.h"
#include "datapath.h"
#include "flow.h"
#include "flow_netlink.h"
#include "vport.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 cpu = smp_processor_id();
int len = skb->len + (skb_vlan_tag_present(skb) ? VLAN_HLEN : 0);
stats = rcu_dereference(flow->stats[cpu]);
/* Check if already have CPU-specific stats. */
if (likely(stats)) {
spin_lock(&stats->lock);
/* Mark if we write on the pre-allocated stats. */
if (cpu == 0 && unlikely(flow->stats_last_writer != cpu))
flow->stats_last_writer = cpu;
} else {
stats = rcu_dereference(flow->stats[0]); /* Pre-allocated. */
spin_lock(&stats->lock);
/* If the current CPU is the only writer on the
* pre-allocated stats keep using them.
*/
if (unlikely(flow->stats_last_writer != cpu)) {
/* A previous locker may have already allocated the
* stats, so we need to check again. If CPU-specific
* stats were already allocated, we update the pre-
* allocated stats as we have already locked them.
*/
if (likely(flow->stats_last_writer != -1) &&
likely(!rcu_access_pointer(flow->stats[cpu]))) {
/* Try to allocate CPU-specific stats. */
struct flow_stats *new_stats;
new_stats =
kmem_cache_alloc_node(flow_stats_cache,
GFP_NOWAIT |
__GFP_THISNODE |
__GFP_NOWARN |
__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[cpu],
new_stats);
goto unlock;
}
}
flow->stats_last_writer = cpu;
}
}
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 cpu;
*used = 0;
*tcp_flags = 0;
memset(ovs_stats, 0, sizeof(*ovs_stats));
/* We open code this to make sure cpu 0 is always considered */
for (cpu = 0; cpu < nr_cpu_ids; cpu = cpumask_next(cpu, cpu_possible_mask)) {
struct flow_stats *stats = rcu_dereference_ovsl(flow->stats[cpu]);
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 cpu;
/* We open code this to make sure cpu 0 is always considered */
for (cpu = 0; cpu < nr_cpu_ids; cpu = cpumask_next(cpu, cpu_possible_mask)) {
struct flow_stats *stats = ovsl_dereference(flow->stats[cpu]);
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 (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;
}
/* Delayed handling of error in ipv6_skip_exthdr() as it
* always sets frag_off to a valid value which may be
* used to set key->ip.frag above.
*/
if (unlikely(payload_ofs < 0))
return -EPROTO;
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));
}
/**
* Parse vlan tag from vlan header.
* Returns ERROR on memory error.
* Returns 0 if it encounters a non-vlan or incomplete packet.
* Returns 1 after successfully parsing vlan tag.
*/
static int parse_vlan_tag(struct sk_buff *skb, struct vlan_head *key_vh,
bool untag_vlan)
{
struct vlan_head *vh = (struct vlan_head *)skb->data;
if (likely(!eth_type_vlan(vh->tpid)))
return 0;
if (unlikely(skb->len < sizeof(struct vlan_head) + sizeof(__be16)))
return 0;
if (unlikely(!pskb_may_pull(skb, sizeof(struct vlan_head) +
sizeof(__be16))))
return -ENOMEM;
vh = (struct vlan_head *)skb->data;
key_vh->tci = vh->tci | htons(VLAN_TAG_PRESENT);
key_vh->tpid = vh->tpid;
if (unlikely(untag_vlan)) {
int offset = skb->data - skb_mac_header(skb);
u16 tci;
int err;
__skb_push(skb, offset);
err = __skb_vlan_pop(skb, &tci);
__skb_pull(skb, offset);
if (err)
return err;
__vlan_hwaccel_put_tag(skb, key_vh->tpid, tci);
} else {
__skb_pull(skb, sizeof(struct vlan_head));
}
return 1;
}
static void clear_vlan(struct sw_flow_key *key)
{
key->eth.vlan.tci = 0;
key->eth.vlan.tpid = 0;
key->eth.cvlan.tci = 0;
key->eth.cvlan.tpid = 0;
}
static int parse_vlan(struct sk_buff *skb, struct sw_flow_key *key)
{
int res;
if (skb_vlan_tag_present(skb)) {
key->eth.vlan.tci = htons(skb->vlan_tci);
key->eth.vlan.tpid = skb->vlan_proto;
} else {
/* Parse outer vlan tag in the non-accelerated case. */
res = parse_vlan_tag(skb, &key->eth.vlan, true);
if (res <= 0)
return res;
}
/* Parse inner vlan tag. */
res = parse_vlan_tag(skb, &key->eth.cvlan, false);
if (res <= 0)
return res;
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 (eth_proto_is_802_3(proto))
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 (eth_proto_is_802_3(llc->ethertype))
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 fields as follows:
*
* - skb->mac_header: the L2 header.
*
* - skb->network_header: just past the L2 header, or just past the
* VLAN header, to the first byte of the L2 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.
*
* - skb->protocol: the type of the data starting at skb->network_header.
* Equals to key->eth.type.
*/
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. */
clear_vlan(key);
if (key->mac_proto == MAC_PROTO_NONE) {
if (unlikely(eth_type_vlan(skb->protocol)))
return -EINVAL;
skb_reset_network_header(skb);
} else {
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.
*/
if (unlikely(parse_vlan(skb, key)))
return -ENOMEM;
skb->protocol = parse_ethertype(skb);
if (unlikely(skb->protocol == htons(0)))
return -ENOMEM;
skb_reset_network_header(skb);
__skb_push(skb, skb->data - skb_mac_header(skb));
}
skb_reset_mac_len(skb);
key->eth.type = skb->protocol;
/* 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;
skb_set_inner_network_header(skb, skb->mac_len);
while (1) {
__be32 lse;
error = check_header(skb, skb->mac_len + stack_len);
if (unlikely(error))
return 0;
memcpy(&lse, skb_inner_network_header(skb), MPLS_HLEN);
if (stack_len == MPLS_HLEN)
memcpy(&key->mpls.top_lse, &lse, MPLS_HLEN);
skb_set_inner_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)) {
switch (nh_len) {
case -EINVAL:
memset(&key->ip, 0, sizeof(key->ip));
memset(&key->ipv6.addr, 0, sizeof(key->ipv6.addr));
/* fall-through */
case -EPROTO:
skb->transport_header = skb->network_header;
error = 0;
break;
default:
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);
}
static int key_extract_mac_proto(struct sk_buff *skb)
{
switch (skb->dev->type) {
case ARPHRD_ETHER:
return MAC_PROTO_ETHERNET;
case ARPHRD_NONE:
if (skb->protocol == htons(ETH_P_TEB))
return MAC_PROTO_ETHERNET;
return MAC_PROTO_NONE;
}
WARN_ON_ONCE(1);
return -EINVAL;
}
int ovs_flow_key_extract(const struct ip_tunnel_info *tun_info,
struct sk_buff *skb, struct sw_flow_key *key)
{
int res, err;
/* Extract metadata from packet. */
if (tun_info) {
key->tun_proto = ip_tunnel_info_af(tun_info);
memcpy(&key->tun_key, &tun_info->key, sizeof(key->tun_key));
if (tun_info->options_len) {
BUILD_BUG_ON((1 << (sizeof(tun_info->options_len) *
8)) - 1
> sizeof(key->tun_opts));
ip_tunnel_info_opts_get(TUN_METADATA_OPTS(key, tun_info->options_len),
tun_info);
key->tun_opts_len = tun_info->options_len;
} else {
key->tun_opts_len = 0;
}
} else {
key->tun_proto = 0;
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;
res = key_extract_mac_proto(skb);
if (res < 0)
return res;
key->mac_proto = res;
key->recirc_id = 0;
err = key_extract(skb, key);
if (!err)
ovs_ct_fill_key(skb, key); /* Must be after key_extract(). */
return err;
}
int ovs_flow_key_extract_userspace(struct net *net, const struct nlattr *attr,
struct sk_buff *skb,
struct sw_flow_key *key, bool log)
{
const struct nlattr *a[OVS_KEY_ATTR_MAX + 1];
u64 attrs = 0;
int err;
err = parse_flow_nlattrs(attr, a, &attrs, log);
if (err)
return -EINVAL;
/* Extract metadata from netlink attributes. */
err = ovs_nla_get_flow_metadata(net, a, attrs, key, log);
if (err)
return err;
/* key_extract assumes that skb->protocol is set-up for
* layer 3 packets which is the case for other callers,
* in particular packets received from the network stack.
* Here the correct value can be set from the metadata
* extracted above.
* For L2 packet key eth type would be zero. skb protocol
* would be set to correct value later during key-extact.
*/
skb->protocol = key->eth.type;
err = key_extract(skb, key);
if (err)
return err;
/* Check that we have conntrack original direction tuple metadata only
* for packets for which it makes sense. Otherwise the key may be
* corrupted due to overlapping key fields.
*/
if (attrs & (1 << OVS_KEY_ATTR_CT_ORIG_TUPLE_IPV4) &&
key->eth.type != htons(ETH_P_IP))
return -EINVAL;
if (attrs & (1 << OVS_KEY_ATTR_CT_ORIG_TUPLE_IPV6) &&
(key->eth.type != htons(ETH_P_IPV6) ||
sw_flow_key_is_nd(key)))
return -EINVAL;
return 0;
}