mir/ovs
2
0
Fork 0
mirror of https://github.com/openvswitch/ovs synced 2025-09-05 16:55:42 +00:00
Code Issues Releases Wiki Activity
Files
deedf7e78b249383d6f7b385f9d04e08e33d0e3f
ovs/lib/flow.c
Ben Pfaff deedf7e78b flow: Rename 'priority' to 'skb_priority'. 
This priority's mean is completely different from the priority of an
OpenFlow rule, so it is confusing for it to have the same name.

We should be on the lookout for a less Linux-specific name, but this one
seems fine for now.

Signed-off-by: Ben Pfaff <blp@nicira.com>
2011-12-21 15:52:38 -08:00

1064 lines
32 KiB
C
Raw Blame History

This file contains invisible Unicode characters

This file contains invisible Unicode characters that are indistinguishable to humans but may be processed differently by a computer. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

/*
* Copyright (c) 2008, 2009, 2010, 2011 Nicira Networks.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at:
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include <config.h>
#include <sys/types.h>
#include "flow.h"
#include <assert.h>
#include <errno.h>
#include <inttypes.h>
#include <netinet/in.h>
#include <netinet/icmp6.h>
#include <netinet/ip6.h>
#include <stdlib.h>
#include <string.h>
#include "byte-order.h"
#include "coverage.h"
#include "dynamic-string.h"
#include "hash.h"
#include "ofpbuf.h"
#include "openflow/openflow.h"
#include "packets.h"
#include "unaligned.h"
#include "vlog.h"
VLOG_DEFINE_THIS_MODULE(flow);
COVERAGE_DEFINE(flow_extract);
static struct arp_eth_header *
pull_arp(struct ofpbuf *packet)
{
return ofpbuf_try_pull(packet, ARP_ETH_HEADER_LEN);
}
static struct ip_header *
pull_ip(struct ofpbuf *packet)
{
if (packet->size >= IP_HEADER_LEN) {
struct ip_header *ip = packet->data;
int ip_len = IP_IHL(ip->ip_ihl_ver) * 4;
if (ip_len >= IP_HEADER_LEN && packet->size >= ip_len) {
return ofpbuf_pull(packet, ip_len);
}
}
return NULL;
}
static struct tcp_header *
pull_tcp(struct ofpbuf *packet)
{
if (packet->size >= TCP_HEADER_LEN) {
struct tcp_header *tcp = packet->data;
int tcp_len = TCP_OFFSET(tcp->tcp_ctl) * 4;
if (tcp_len >= TCP_HEADER_LEN && packet->size >= tcp_len) {
return ofpbuf_pull(packet, tcp_len);
}
}
return NULL;
}
static struct udp_header *
pull_udp(struct ofpbuf *packet)
{
return ofpbuf_try_pull(packet, UDP_HEADER_LEN);
}
static struct icmp_header *
pull_icmp(struct ofpbuf *packet)
{
return ofpbuf_try_pull(packet, ICMP_HEADER_LEN);
}
static struct icmp6_hdr *
pull_icmpv6(struct ofpbuf *packet)
{
return ofpbuf_try_pull(packet, sizeof(struct icmp6_hdr));
}
static void
parse_vlan(struct ofpbuf *b, struct flow *flow)
{
struct qtag_prefix {
ovs_be16 eth_type; /* ETH_TYPE_VLAN */
ovs_be16 tci;
};
if (b->size >= sizeof(struct qtag_prefix) + sizeof(ovs_be16)) {
struct qtag_prefix *qp = ofpbuf_pull(b, sizeof *qp);
flow->vlan_tci = qp->tci | htons(VLAN_CFI);
}
}
static ovs_be16
parse_ethertype(struct ofpbuf *b)
{
struct llc_snap_header *llc;
ovs_be16 proto;
proto = *(ovs_be16 *) ofpbuf_pull(b, sizeof proto);
if (ntohs(proto) >= ETH_TYPE_MIN) {
return proto;
}
if (b->size < sizeof *llc) {
return htons(FLOW_DL_TYPE_NONE);
}
llc = b->data;
if (llc->llc.llc_dsap != LLC_DSAP_SNAP
|| llc->llc.llc_ssap != LLC_SSAP_SNAP
|| llc->llc.llc_cntl != LLC_CNTL_SNAP
|| memcmp(llc->snap.snap_org, SNAP_ORG_ETHERNET,
sizeof llc->snap.snap_org)) {
return htons(FLOW_DL_TYPE_NONE);
}
ofpbuf_pull(b, sizeof *llc);
return llc->snap.snap_type;
}
static int
parse_ipv6(struct ofpbuf *packet, struct flow *flow)
{
const struct ip6_hdr *nh;
ovs_be32 tc_flow;
int nexthdr;
nh = ofpbuf_try_pull(packet, sizeof *nh);
if (!nh) {
return EINVAL;
}
nexthdr = nh->ip6_nxt;
flow->ipv6_src = nh->ip6_src;
flow->ipv6_dst = nh->ip6_dst;
tc_flow = get_unaligned_be32(&nh->ip6_flow);
flow->nw_tos = ntohl(tc_flow) >> 20;
flow->ipv6_label = tc_flow & htonl(IPV6_LABEL_MASK);
flow->nw_ttl = nh->ip6_hlim;
flow->nw_proto = IPPROTO_NONE;
while (1) {
if ((nexthdr != IPPROTO_HOPOPTS)
&& (nexthdr != IPPROTO_ROUTING)
&& (nexthdr != IPPROTO_DSTOPTS)
&& (nexthdr != IPPROTO_AH)
&& (nexthdr != IPPROTO_FRAGMENT)) {
/* It's either a terminal header (e.g., TCP, UDP) or one we
* don't understand. In either case, we're done with the
* packet, so use it to fill in 'nw_proto'. */
break;
}
/* We only verify that at least 8 bytes of the next header are
* available, but many of these headers are longer. Ensure that
* accesses within the extension header are within those first 8
* bytes. All extension headers are required to be at least 8
* bytes. */
if (packet->size < 8) {
return EINVAL;
}
if ((nexthdr == IPPROTO_HOPOPTS)
|| (nexthdr == IPPROTO_ROUTING)
|| (nexthdr == IPPROTO_DSTOPTS)) {
/* These headers, while different, have the fields we care about
* in the same location and with the same interpretation. */
const struct ip6_ext *ext_hdr = (struct ip6_ext *)packet->data;
nexthdr = ext_hdr->ip6e_nxt;
if (!ofpbuf_try_pull(packet, (ext_hdr->ip6e_len + 1) * 8)) {
return EINVAL;
}
} else if (nexthdr == IPPROTO_AH) {
/* A standard AH definition isn't available, but the fields
* we care about are in the same location as the generic
* option header--only the header length is calculated
* differently. */
const struct ip6_ext *ext_hdr = (struct ip6_ext *)packet->data;
nexthdr = ext_hdr->ip6e_nxt;
if (!ofpbuf_try_pull(packet, (ext_hdr->ip6e_len + 2) * 4)) {
return EINVAL;
}
} else if (nexthdr == IPPROTO_FRAGMENT) {
const struct ip6_frag *frag_hdr = (struct ip6_frag *)packet->data;
nexthdr = frag_hdr->ip6f_nxt;
if (!ofpbuf_try_pull(packet, sizeof *frag_hdr)) {
return EINVAL;
}
/* We only process the first fragment. */
if (frag_hdr->ip6f_offlg != htons(0)) {
if ((frag_hdr->ip6f_offlg & IP6F_OFF_MASK) == htons(0)) {
flow->nw_frag = FLOW_NW_FRAG_ANY;
} else {
flow->nw_frag |= FLOW_NW_FRAG_LATER;
nexthdr = IPPROTO_FRAGMENT;
break;
}
}
}
}
flow->nw_proto = nexthdr;
return 0;
}
static void
parse_tcp(struct ofpbuf *packet, struct ofpbuf *b, struct flow *flow)
{
const struct tcp_header *tcp = pull_tcp(b);
if (tcp) {
flow->tp_src = tcp->tcp_src;
flow->tp_dst = tcp->tcp_dst;
packet->l7 = b->data;
}
}
static void
parse_udp(struct ofpbuf *packet, struct ofpbuf *b, struct flow *flow)
{
const struct udp_header *udp = pull_udp(b);
if (udp) {
flow->tp_src = udp->udp_src;
flow->tp_dst = udp->udp_dst;
packet->l7 = b->data;
}
}
static bool
parse_icmpv6(struct ofpbuf *b, struct flow *flow)
{
const struct icmp6_hdr *icmp = pull_icmpv6(b);
if (!icmp) {
return false;
}
/* 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. */
flow->tp_src = htons(icmp->icmp6_type);
flow->tp_dst = htons(icmp->icmp6_code);
if (icmp->icmp6_code == 0 &&
(icmp->icmp6_type == ND_NEIGHBOR_SOLICIT ||
icmp->icmp6_type == ND_NEIGHBOR_ADVERT)) {
const struct in6_addr *nd_target;
nd_target = ofpbuf_try_pull(b, sizeof *nd_target);
if (!nd_target) {
return false;
}
flow->nd_target = *nd_target;
while (b->size >= 8) {
/* The minimum size of an option is 8 bytes, which also is
* the size of Ethernet link-layer options. */
const struct nd_opt_hdr *nd_opt = b->data;
int opt_len = nd_opt->nd_opt_len * 8;
if (!opt_len || opt_len > b->size) {
goto invalid;
}
/* 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_LINKADDR
&& opt_len == 8) {
if (eth_addr_is_zero(flow->arp_sha)) {
memcpy(flow->arp_sha, nd_opt + 1, ETH_ADDR_LEN);
} else {
goto invalid;
}
} else if (nd_opt->nd_opt_type == ND_OPT_TARGET_LINKADDR
&& opt_len == 8) {
if (eth_addr_is_zero(flow->arp_tha)) {
memcpy(flow->arp_tha, nd_opt + 1, ETH_ADDR_LEN);
} else {
goto invalid;
}
}
if (!ofpbuf_try_pull(b, opt_len)) {
goto invalid;
}
}
}
return true;
invalid:
memset(&flow->nd_target, 0, sizeof(flow->nd_target));
memset(flow->arp_sha, 0, sizeof(flow->arp_sha));
memset(flow->arp_tha, 0, sizeof(flow->arp_tha));
return false;
}
/* Initializes 'flow' members from 'packet', 'skb_priority', 'tun_id', and
* 'ofp_in_port'.
*
* Initializes 'packet' header pointers as follows:
*
* - packet->l2 to the start of the Ethernet header.
*
* - packet->l3 to just past the Ethernet header, or just past the
* vlan_header if one is present, to the first byte of the payload of the
* Ethernet frame.
*
* - packet->l4 to just past the IPv4 header, if one is present and has a
* correct length, and otherwise NULL.
*
* - packet->l7 to just past the TCP or UDP or ICMP header, if one is
* present and has a correct length, and otherwise NULL.
*/
void
flow_extract(struct ofpbuf *packet, uint32_t skb_priority, ovs_be64 tun_id,
uint16_t ofp_in_port, struct flow *flow)
{
struct ofpbuf b = *packet;
struct eth_header *eth;
COVERAGE_INC(flow_extract);
memset(flow, 0, sizeof *flow);
flow->tun_id = tun_id;
flow->in_port = ofp_in_port;
flow->skb_priority = skb_priority;
packet->l2 = b.data;
packet->l3 = NULL;
packet->l4 = NULL;
packet->l7 = NULL;
if (b.size < sizeof *eth) {
return;
}
/* Link layer. */
eth = b.data;
memcpy(flow->dl_src, eth->eth_src, ETH_ADDR_LEN);
memcpy(flow->dl_dst, eth->eth_dst, ETH_ADDR_LEN);
/* dl_type, vlan_tci. */
ofpbuf_pull(&b, ETH_ADDR_LEN * 2);
if (eth->eth_type == htons(ETH_TYPE_VLAN)) {
parse_vlan(&b, flow);
}
flow->dl_type = parse_ethertype(&b);
/* Network layer. */
packet->l3 = b.data;
if (flow->dl_type == htons(ETH_TYPE_IP)) {
const struct ip_header *nh = pull_ip(&b);
if (nh) {
packet->l4 = b.data;
flow->nw_src = get_unaligned_be32(&nh->ip_src);
flow->nw_dst = get_unaligned_be32(&nh->ip_dst);
flow->nw_proto = nh->ip_proto;
flow->nw_tos = nh->ip_tos;
if (IP_IS_FRAGMENT(nh->ip_frag_off)) {
flow->nw_frag = FLOW_NW_FRAG_ANY;
if (nh->ip_frag_off & htons(IP_FRAG_OFF_MASK)) {
flow->nw_frag |= FLOW_NW_FRAG_LATER;
}
}
flow->nw_ttl = nh->ip_ttl;
if (!(nh->ip_frag_off & htons(IP_FRAG_OFF_MASK))) {
if (flow->nw_proto == IPPROTO_TCP) {
parse_tcp(packet, &b, flow);
} else if (flow->nw_proto == IPPROTO_UDP) {
parse_udp(packet, &b, flow);
} else if (flow->nw_proto == IPPROTO_ICMP) {
const struct icmp_header *icmp = pull_icmp(&b);
if (icmp) {
flow->tp_src = htons(icmp->icmp_type);
flow->tp_dst = htons(icmp->icmp_code);
packet->l7 = b.data;
}
}
}
}
} else if (flow->dl_type == htons(ETH_TYPE_IPV6)) {
if (parse_ipv6(&b, flow)) {
return;
}
packet->l4 = b.data;
if (flow->nw_proto == IPPROTO_TCP) {
parse_tcp(packet, &b, flow);
} else if (flow->nw_proto == IPPROTO_UDP) {
parse_udp(packet, &b, flow);
} else if (flow->nw_proto == IPPROTO_ICMPV6) {
if (parse_icmpv6(&b, flow)) {
packet->l7 = b.data;
}
}
} else if (flow->dl_type == htons(ETH_TYPE_ARP)) {
const struct arp_eth_header *arp = pull_arp(&b);
if (arp && arp->ar_hrd == htons(1)
&& arp->ar_pro == htons(ETH_TYPE_IP)
&& arp->ar_hln == ETH_ADDR_LEN
&& arp->ar_pln == 4) {
/* We only match on the lower 8 bits of the opcode. */
if (ntohs(arp->ar_op) <= 0xff) {
flow->nw_proto = ntohs(arp->ar_op);
}
if ((flow->nw_proto == ARP_OP_REQUEST)
|| (flow->nw_proto == ARP_OP_REPLY)) {
flow->nw_src = arp->ar_spa;
flow->nw_dst = arp->ar_tpa;
memcpy(flow->arp_sha, arp->ar_sha, ETH_ADDR_LEN);
memcpy(flow->arp_tha, arp->ar_tha, ETH_ADDR_LEN);
}
}
}
}
/* For every bit of a field that is wildcarded in 'wildcards', sets the
* corresponding bit in 'flow' to zero. */
void
flow_zero_wildcards(struct flow *flow, const struct flow_wildcards *wildcards)
{
const flow_wildcards_t wc = wildcards->wildcards;
int i;
BUILD_ASSERT_DECL(FLOW_WC_SEQ == 7);
for (i = 0; i < FLOW_N_REGS; i++) {
flow->regs[i] &= wildcards->reg_masks[i];
}
flow->tun_id &= wildcards->tun_id_mask;
flow->nw_src &= wildcards->nw_src_mask;
flow->nw_dst &= wildcards->nw_dst_mask;
if (wc & FWW_IN_PORT) {
flow->in_port = 0;
}
flow->vlan_tci &= wildcards->vlan_tci_mask;
if (wc & FWW_DL_TYPE) {
flow->dl_type = htons(0);
}
if (wc & FWW_TP_SRC) {
flow->tp_src = htons(0);
}
if (wc & FWW_TP_DST) {
flow->tp_dst = htons(0);
}
if (wc & FWW_DL_SRC) {
memset(flow->dl_src, 0, sizeof flow->dl_src);
}
if (wc & FWW_DL_DST) {
flow->dl_dst[0] &= 0x01;
memset(&flow->dl_dst[1], 0, 5);
}
if (wc & FWW_ETH_MCAST) {
flow->dl_dst[0] &= 0xfe;
}
if (wc & FWW_NW_PROTO) {
flow->nw_proto = 0;
}
if (wc & FWW_IPV6_LABEL) {
flow->ipv6_label = htonl(0);
}
if (wc & FWW_NW_DSCP) {
flow->nw_tos &= ~IP_DSCP_MASK;
}
if (wc & FWW_NW_ECN) {
flow->nw_tos &= ~IP_ECN_MASK;
}
if (wc & FWW_NW_TTL) {
flow->nw_ttl = 0;
}
flow->nw_frag &= wildcards->nw_frag_mask;
if (wc & FWW_ARP_SHA) {
memset(flow->arp_sha, 0, sizeof flow->arp_sha);
}
if (wc & FWW_ARP_THA) {
memset(flow->arp_tha, 0, sizeof flow->arp_tha);
}
flow->ipv6_src = ipv6_addr_bitand(&flow->ipv6_src,
&wildcards->ipv6_src_mask);
flow->ipv6_dst = ipv6_addr_bitand(&flow->ipv6_dst,
&wildcards->ipv6_dst_mask);
if (wc & FWW_ND_TARGET) {
memset(&flow->nd_target, 0, sizeof flow->nd_target);
}
flow->skb_priority = 0;
}
char *
flow_to_string(const struct flow *flow)
{
struct ds ds = DS_EMPTY_INITIALIZER;
flow_format(&ds, flow);
return ds_cstr(&ds);
}
void
flow_format(struct ds *ds, const struct flow *flow)
{
ds_put_format(ds, "priority%"PRIu32
":tunnel%#"PRIx64
":in_port%04"PRIx16,
flow->skb_priority,
ntohll(flow->tun_id),
flow->in_port);
ds_put_format(ds, ":tci(");
if (flow->vlan_tci) {
ds_put_format(ds, "vlan%"PRIu16",pcp%d",
vlan_tci_to_vid(flow->vlan_tci),
vlan_tci_to_pcp(flow->vlan_tci));
} else {
ds_put_char(ds, '0');
}
ds_put_format(ds, ") mac"ETH_ADDR_FMT"->"ETH_ADDR_FMT
" type%04"PRIx16,
ETH_ADDR_ARGS(flow->dl_src),
ETH_ADDR_ARGS(flow->dl_dst),
ntohs(flow->dl_type));
if (flow->dl_type == htons(ETH_TYPE_IPV6)) {
ds_put_format(ds, " label%#"PRIx32" proto%"PRIu8" tos%#"PRIx8
" ttl%"PRIu8" ipv6",
ntohl(flow->ipv6_label), flow->nw_proto,
flow->nw_tos, flow->nw_ttl);
print_ipv6_addr(ds, &flow->ipv6_src);
ds_put_cstr(ds, "->");
print_ipv6_addr(ds, &flow->ipv6_dst);
} else {
ds_put_format(ds, " proto%"PRIu8" tos%#"PRIx8" ttl%"PRIu8
" ip"IP_FMT"->"IP_FMT,
flow->nw_proto, flow->nw_tos, flow->nw_ttl,
IP_ARGS(&flow->nw_src), IP_ARGS(&flow->nw_dst));
}
if (flow->nw_frag) {
ds_put_format(ds, " frag(%s)",
flow->nw_frag == FLOW_NW_FRAG_ANY ? "first"
: flow->nw_frag == (FLOW_NW_FRAG_ANY | FLOW_NW_FRAG_LATER)
? "later" : "<error>");
}
if (flow->tp_src || flow->tp_dst) {
ds_put_format(ds, " port%"PRIu16"->%"PRIu16,
ntohs(flow->tp_src), ntohs(flow->tp_dst));
}
if (!eth_addr_is_zero(flow->arp_sha) || !eth_addr_is_zero(flow->arp_tha)) {
ds_put_format(ds, " arp_ha"ETH_ADDR_FMT"->"ETH_ADDR_FMT,
ETH_ADDR_ARGS(flow->arp_sha),
ETH_ADDR_ARGS(flow->arp_tha));
}
}
void
flow_print(FILE *stream, const struct flow *flow)
{
char *s = flow_to_string(flow);
fputs(s, stream);
free(s);
}
/* flow_wildcards functions. */
/* Initializes 'wc' as a set of wildcards that matches every packet. */
void
flow_wildcards_init_catchall(struct flow_wildcards *wc)
{
BUILD_ASSERT_DECL(FLOW_WC_SEQ == 7);
wc->wildcards = FWW_ALL;
wc->tun_id_mask = htonll(0);
wc->nw_src_mask = htonl(0);
wc->nw_dst_mask = htonl(0);
wc->ipv6_src_mask = in6addr_any;
wc->ipv6_dst_mask = in6addr_any;
memset(wc->reg_masks, 0, sizeof wc->reg_masks);
wc->vlan_tci_mask = htons(0);
wc->nw_frag_mask = 0;
memset(wc->zeros, 0, sizeof wc->zeros);
}
/* Initializes 'wc' as an exact-match set of wildcards; that is, 'wc' does not
* wildcard any bits or fields. */
void
flow_wildcards_init_exact(struct flow_wildcards *wc)
{
BUILD_ASSERT_DECL(FLOW_WC_SEQ == 7);
wc->wildcards = 0;
wc->tun_id_mask = htonll(UINT64_MAX);
wc->nw_src_mask = htonl(UINT32_MAX);
wc->nw_dst_mask = htonl(UINT32_MAX);
wc->ipv6_src_mask = in6addr_exact;
wc->ipv6_dst_mask = in6addr_exact;
memset(wc->reg_masks, 0xff, sizeof wc->reg_masks);
wc->vlan_tci_mask = htons(UINT16_MAX);
wc->nw_frag_mask = UINT8_MAX;
memset(wc->zeros, 0, sizeof wc->zeros);
}
/* Returns true if 'wc' is exact-match, false if 'wc' wildcards any bits or
* fields. */
bool
flow_wildcards_is_exact(const struct flow_wildcards *wc)
{
int i;
BUILD_ASSERT_DECL(FLOW_WC_SEQ == 7);
if (wc->wildcards
|| wc->tun_id_mask != htonll(UINT64_MAX)
|| wc->nw_src_mask != htonl(UINT32_MAX)
|| wc->nw_dst_mask != htonl(UINT32_MAX)
|| wc->vlan_tci_mask != htons(UINT16_MAX)
|| !ipv6_mask_is_exact(&wc->ipv6_src_mask)
|| !ipv6_mask_is_exact(&wc->ipv6_dst_mask)
|| wc->nw_frag_mask != UINT8_MAX) {
return false;
}
for (i = 0; i < FLOW_N_REGS; i++) {
if (wc->reg_masks[i] != UINT32_MAX) {
return false;
}
}
return true;
}
/* Returns true if 'wc' matches every packet, false if 'wc' fixes any bits or
* fields. */
bool
flow_wildcards_is_catchall(const struct flow_wildcards *wc)
{
int i;
BUILD_ASSERT_DECL(FLOW_WC_SEQ == 7);
if (wc->wildcards != FWW_ALL
|| wc->tun_id_mask != htonll(0)
|| wc->nw_src_mask != htonl(0)
|| wc->nw_dst_mask != htonl(0)
|| wc->vlan_tci_mask != htons(0)
|| !ipv6_mask_is_any(&wc->ipv6_src_mask)
|| !ipv6_mask_is_any(&wc->ipv6_dst_mask)
|| wc->nw_frag_mask != 0) {
return false;
}
for (i = 0; i < FLOW_N_REGS; i++) {
if (wc->reg_masks[i] != 0) {
return false;
}
}
return true;
}
/* Initializes 'dst' as the combination of wildcards in 'src1' and 'src2'.
* That is, a bit or a field is wildcarded in 'dst' if it is wildcarded in
* 'src1' or 'src2' or both. */
void
flow_wildcards_combine(struct flow_wildcards *dst,
const struct flow_wildcards *src1,
const struct flow_wildcards *src2)
{
int i;
dst->wildcards = src1->wildcards | src2->wildcards;
dst->tun_id_mask = src1->tun_id_mask & src2->tun_id_mask;
dst->nw_src_mask = src1->nw_src_mask & src2->nw_src_mask;
dst->nw_dst_mask = src1->nw_dst_mask & src2->nw_dst_mask;
dst->ipv6_src_mask = ipv6_addr_bitand(&src1->ipv6_src_mask,
&src2->ipv6_src_mask);
dst->ipv6_dst_mask = ipv6_addr_bitand(&src1->ipv6_dst_mask,
&src2->ipv6_dst_mask);
for (i = 0; i < FLOW_N_REGS; i++) {
dst->reg_masks[i] = src1->reg_masks[i] & src2->reg_masks[i];
}
dst->vlan_tci_mask = src1->vlan_tci_mask & src2->vlan_tci_mask;
}
/* Returns a hash of the wildcards in 'wc'. */
uint32_t
flow_wildcards_hash(const struct flow_wildcards *wc, uint32_t basis)
{
/* If you change struct flow_wildcards and thereby trigger this
* assertion, please check that the new struct flow_wildcards has no holes
* in it before you update the assertion. */
BUILD_ASSERT_DECL(sizeof *wc == 60 + FLOW_N_REGS * 4);
return hash_bytes(wc, sizeof *wc, basis);
}
/* Returns true if 'a' and 'b' represent the same wildcards, false if they are
* different. */
bool
flow_wildcards_equal(const struct flow_wildcards *a,
const struct flow_wildcards *b)
{
int i;
if (a->wildcards != b->wildcards
|| a->tun_id_mask != b->tun_id_mask
|| a->nw_src_mask != b->nw_src_mask
|| a->nw_dst_mask != b->nw_dst_mask
|| a->vlan_tci_mask != b->vlan_tci_mask
|| !ipv6_addr_equals(&a->ipv6_src_mask, &b->ipv6_src_mask)
|| !ipv6_addr_equals(&a->ipv6_dst_mask, &b->ipv6_dst_mask)) {
return false;
}
for (i = 0; i < FLOW_N_REGS; i++) {
if (a->reg_masks[i] != b->reg_masks[i]) {
return false;
}
}
return true;
}
/* Returns true if at least one bit or field is wildcarded in 'a' but not in
* 'b', false otherwise. */
bool
flow_wildcards_has_extra(const struct flow_wildcards *a,
const struct flow_wildcards *b)
{
int i;
struct in6_addr ipv6_masked;
for (i = 0; i < FLOW_N_REGS; i++) {
if ((a->reg_masks[i] & b->reg_masks[i]) != b->reg_masks[i]) {
return true;
}
}
ipv6_masked = ipv6_addr_bitand(&a->ipv6_src_mask, &b->ipv6_src_mask);
if (!ipv6_addr_equals(&ipv6_masked, &b->ipv6_src_mask)) {
return true;
}
ipv6_masked = ipv6_addr_bitand(&a->ipv6_dst_mask, &b->ipv6_dst_mask);
if (!ipv6_addr_equals(&ipv6_masked, &b->ipv6_dst_mask)) {
return true;
}
return (a->wildcards & ~b->wildcards
|| (a->tun_id_mask & b->tun_id_mask) != b->tun_id_mask
|| (a->nw_src_mask & b->nw_src_mask) != b->nw_src_mask
|| (a->nw_dst_mask & b->nw_dst_mask) != b->nw_dst_mask
|| (a->vlan_tci_mask & b->vlan_tci_mask) != b->vlan_tci_mask);
}
/* Sets the wildcard mask for register 'idx' in 'wc' to 'mask'.
* (A 0-bit indicates a wildcard bit.) */
void
flow_wildcards_set_reg_mask(struct flow_wildcards *wc, int idx, uint32_t mask)
{
wc->reg_masks[idx] = mask;
}
/* Returns the wildcard bitmask for the Ethernet destination address
* that 'wc' specifies. The bitmask has a 0 in each bit that is wildcarded
* and a 1 in each bit that must match. */
const uint8_t *
flow_wildcards_to_dl_dst_mask(flow_wildcards_t wc)
{
static const uint8_t no_wild[] = {0xff, 0xff, 0xff, 0xff, 0xff, 0xff};
static const uint8_t addr_wild[] = {0x01, 0x00, 0x00, 0x00, 0x00, 0x00};
static const uint8_t mcast_wild[] = {0xfe, 0xff, 0xff, 0xff, 0xff, 0xff};
static const uint8_t all_wild[] = {0x00, 0x00, 0x00, 0x00, 0x00, 0x00};
switch (wc & (FWW_DL_DST | FWW_ETH_MCAST)) {
case 0: return no_wild;
case FWW_DL_DST: return addr_wild;
case FWW_ETH_MCAST: return mcast_wild;
case FWW_DL_DST | FWW_ETH_MCAST: return all_wild;
}
NOT_REACHED();
}
/* Returns true if 'mask' is a valid wildcard bitmask for the Ethernet
* destination address. Valid bitmasks are either all-bits-0 or all-bits-1,
* except that the multicast bit may differ from the rest of the bits. So,
* there are four possible valid bitmasks:
*
* - 00:00:00:00:00:00
* - 01:00:00:00:00:00
* - fe:ff:ff:ff:ff:ff
* - ff:ff:ff:ff:ff:ff
*
* All other bitmasks are invalid. */
bool
flow_wildcards_is_dl_dst_mask_valid(const uint8_t mask[ETH_ADDR_LEN])
{
switch (mask[0]) {
case 0x00:
case 0x01:
return (mask[1] | mask[2] | mask[3] | mask[4] | mask[5]) == 0x00;
case 0xfe:
case 0xff:
return (mask[1] & mask[2] & mask[3] & mask[4] & mask[5]) == 0xff;
default:
return false;
}
}
/* Returns 'wc' with the FWW_DL_DST and FWW_ETH_MCAST bits modified
* appropriately to match 'mask'.
*
* This function will assert-fail if 'mask' is invalid. Only 'mask' values
* accepted by flow_wildcards_is_dl_dst_mask_valid() are allowed. */
flow_wildcards_t
flow_wildcards_set_dl_dst_mask(flow_wildcards_t wc,
const uint8_t mask[ETH_ADDR_LEN])
{
assert(flow_wildcards_is_dl_dst_mask_valid(mask));
switch (mask[0]) {
case 0x00:
return wc | FWW_DL_DST | FWW_ETH_MCAST;
case 0x01:
return (wc | FWW_DL_DST) & ~FWW_ETH_MCAST;
case 0xfe:
return (wc & ~FWW_DL_DST) | FWW_ETH_MCAST;
case 0xff:
return wc & ~(FWW_DL_DST | FWW_ETH_MCAST);
default:
NOT_REACHED();
}
}
/* Hashes 'flow' based on its L2 through L4 protocol information. */
uint32_t
flow_hash_symmetric_l4(const struct flow *flow, uint32_t basis)
{
struct {
union {
ovs_be32 ipv4_addr;
struct in6_addr ipv6_addr;
};
ovs_be16 eth_type;
ovs_be16 vlan_tci;
ovs_be16 tp_addr;
uint8_t eth_addr[ETH_ADDR_LEN];
uint8_t ip_proto;
} fields;
int i;
memset(&fields, 0, sizeof fields);
for (i = 0; i < ETH_ADDR_LEN; i++) {
fields.eth_addr[i] = flow->dl_src[i] ^ flow->dl_dst[i];
}
fields.vlan_tci = flow->vlan_tci & htons(VLAN_VID_MASK);
fields.eth_type = flow->dl_type;
/* UDP source and destination port are not taken into account because they
* will not necessarily be symmetric in a bidirectional flow. */
if (fields.eth_type == htons(ETH_TYPE_IP)) {
fields.ipv4_addr = flow->nw_src ^ flow->nw_dst;
fields.ip_proto = flow->nw_proto;
if (fields.ip_proto == IPPROTO_TCP) {
fields.tp_addr = flow->tp_src ^ flow->tp_dst;
}
} else if (fields.eth_type == htons(ETH_TYPE_IPV6)) {
const uint8_t *a = &flow->ipv6_src.s6_addr[0];
const uint8_t *b = &flow->ipv6_dst.s6_addr[0];
uint8_t *ipv6_addr = &fields.ipv6_addr.s6_addr[0];
for (i=0; i<16; i++) {
ipv6_addr[i] = a[i] ^ b[i];
}
fields.ip_proto = flow->nw_proto;
if (fields.ip_proto == IPPROTO_TCP) {
fields.tp_addr = flow->tp_src ^ flow->tp_dst;
}
}
return hash_bytes(&fields, sizeof fields, basis);
}
/* Hashes the portions of 'flow' designated by 'fields'. */
uint32_t
flow_hash_fields(const struct flow *flow, enum nx_hash_fields fields,
uint16_t basis)
{
switch (fields) {
case NX_HASH_FIELDS_ETH_SRC:
return hash_bytes(flow->dl_src, sizeof flow->dl_src, basis);
case NX_HASH_FIELDS_SYMMETRIC_L4:
return flow_hash_symmetric_l4(flow, basis);
}
NOT_REACHED();
}
/* Returns a string representation of 'fields'. */
const char *
flow_hash_fields_to_str(enum nx_hash_fields fields)
{
switch (fields) {
case NX_HASH_FIELDS_ETH_SRC: return "eth_src";
case NX_HASH_FIELDS_SYMMETRIC_L4: return "symmetric_l4";
default: return "<unknown>";
}
}
/* Returns true if the value of 'fields' is supported. Otherwise false. */
bool
flow_hash_fields_valid(enum nx_hash_fields fields)
{
return fields == NX_HASH_FIELDS_ETH_SRC
|| fields == NX_HASH_FIELDS_SYMMETRIC_L4;
}
/* Sets the VLAN VID that 'flow' matches to 'vid', which is interpreted as an
* OpenFlow 1.0 "dl_vlan" value:
*
* - If it is in the range 0...4095, 'flow->vlan_tci' is set to match
* that VLAN. Any existing PCP match is unchanged (it becomes 0 if
* 'flow' previously matched packets without a VLAN header).
*
* - If it is OFP_VLAN_NONE, 'flow->vlan_tci' is set to match a packet
* without a VLAN tag.
*
* - Other values of 'vid' should not be used. */
void
flow_set_vlan_vid(struct flow *flow, ovs_be16 vid)
{
if (vid == htons(OFP_VLAN_NONE)) {
flow->vlan_tci = htons(0);
} else {
vid &= htons(VLAN_VID_MASK);
flow->vlan_tci &= ~htons(VLAN_VID_MASK);
flow->vlan_tci |= htons(VLAN_CFI) | vid;
}
}
/* Sets the VLAN PCP that 'flow' matches to 'pcp', which should be in the
* range 0...7.
*
* This function has no effect on the VLAN ID that 'flow' matches.
*
* After calling this function, 'flow' will not match packets without a VLAN
* header. */
void
flow_set_vlan_pcp(struct flow *flow, uint8_t pcp)
{
pcp &= 0x07;
flow->vlan_tci &= ~htons(VLAN_PCP_MASK);
flow->vlan_tci |= htons((pcp << VLAN_PCP_SHIFT) | VLAN_CFI);
}
/* Puts into 'b' a packet that flow_extract() would parse as having the given
* 'flow'.
*
* (This is useful only for testing, obviously, and the packet isn't really
* valid. It hasn't got any checksums filled in, for one, and lots of fields
* are just zeroed.) */
void
flow_compose(struct ofpbuf *b, const struct flow *flow)
{
eth_compose(b, flow->dl_dst, flow->dl_src, ntohs(flow->dl_type), 0);
if (flow->dl_type == htons(FLOW_DL_TYPE_NONE)) {
struct eth_header *eth = b->l2;
eth->eth_type = htons(b->size);
return;
}
if (flow->vlan_tci & htons(VLAN_CFI)) {
eth_push_vlan(b, flow->vlan_tci & ~htons(VLAN_CFI));
}
if (flow->dl_type == htons(ETH_TYPE_IP)) {
struct ip_header *ip;
b->l3 = ip = ofpbuf_put_zeros(b, sizeof *ip);
ip->ip_ihl_ver = IP_IHL_VER(5, 4);
ip->ip_tos = flow->nw_tos;
ip->ip_proto = flow->nw_proto;
ip->ip_src = flow->nw_src;
ip->ip_dst = flow->nw_dst;
if (flow->nw_frag & FLOW_NW_FRAG_ANY) {
ip->ip_frag_off |= htons(IP_MORE_FRAGMENTS);
if (flow->nw_frag & FLOW_NW_FRAG_LATER) {
ip->ip_frag_off |= htons(100);
}
}
if (!(flow->nw_frag & FLOW_NW_FRAG_ANY)
|| !(flow->nw_frag & FLOW_NW_FRAG_LATER)) {
if (flow->nw_proto == IPPROTO_TCP) {
struct tcp_header *tcp;
b->l4 = tcp = ofpbuf_put_zeros(b, sizeof *tcp);
tcp->tcp_src = flow->tp_src;
tcp->tcp_dst = flow->tp_dst;
tcp->tcp_ctl = TCP_CTL(0, 5);
} else if (flow->nw_proto == IPPROTO_UDP) {
struct udp_header *udp;
b->l4 = udp = ofpbuf_put_zeros(b, sizeof *udp);
udp->udp_src = flow->tp_src;
udp->udp_dst = flow->tp_dst;
} else if (flow->nw_proto == IPPROTO_ICMP) {
struct icmp_header *icmp;
b->l4 = icmp = ofpbuf_put_zeros(b, sizeof *icmp);
icmp->icmp_type = ntohs(flow->tp_src);
icmp->icmp_code = ntohs(flow->tp_dst);
}
}
ip->ip_tot_len = htons((uint8_t *) b->data + b->size
- (uint8_t *) b->l3);
} else if (flow->dl_type == htons(ETH_TYPE_IPV6)) {
/* XXX */
} else if (flow->dl_type == htons(ETH_TYPE_ARP)) {
struct arp_eth_header *arp;
b->l3 = arp = ofpbuf_put_zeros(b, sizeof *arp);
arp->ar_hrd = htons(1);
arp->ar_pro = htons(ETH_TYPE_IP);
arp->ar_hln = ETH_ADDR_LEN;
arp->ar_pln = 4;
arp->ar_op = htons(flow->nw_proto);
if (flow->nw_proto == ARP_OP_REQUEST ||
flow->nw_proto == ARP_OP_REPLY) {
arp->ar_spa = flow->nw_src;
arp->ar_tpa = flow->nw_dst;
memcpy(arp->ar_sha, flow->arp_sha, ETH_ADDR_LEN);
memcpy(arp->ar_tha, flow->arp_tha, ETH_ADDR_LEN);
}
}
}
Reference in New Issue View Git Blame Copy Permalink