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ovs/lib/classifier.c
Justin Pettit 530180fd5a Support matching and modifying IP ECN bits. 
Signed-off-by: Justin Pettit <jpettit@nicira.com>
Acked-by: Jesse Gross <jesse@nicira.com>
2011-11-09 10:47:59 -08:00

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/*
* Copyright (c) 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 "classifier.h"
#include <assert.h>
#include <errno.h>
#include <netinet/in.h>
#include "byte-order.h"
#include "dynamic-string.h"
#include "flow.h"
#include "hash.h"
#include "odp-util.h"
#include "ofp-util.h"
#include "packets.h"
static struct cls_table *find_table(const struct classifier *,
const struct flow_wildcards *);
static struct cls_table *insert_table(struct classifier *,
const struct flow_wildcards *);
static struct cls_table *classifier_first_table(const struct classifier *);
static struct cls_table *classifier_next_table(const struct classifier *,
const struct cls_table *);
static void destroy_table(struct classifier *, struct cls_table *);
static struct cls_rule *find_match(const struct cls_table *,
const struct flow *);
static struct cls_rule *find_equal(struct cls_table *, const struct flow *,
uint32_t hash);
static struct cls_rule *insert_rule(struct cls_table *, struct cls_rule *);
static bool flow_equal_except(const struct flow *, const struct flow *,
const struct flow_wildcards *);
/* Iterates RULE over HEAD and all of the cls_rules on HEAD->list. */
#define FOR_EACH_RULE_IN_LIST(RULE, HEAD) \
for ((RULE) = (HEAD); (RULE) != NULL; (RULE) = next_rule_in_list(RULE))
#define FOR_EACH_RULE_IN_LIST_SAFE(RULE, NEXT, HEAD) \
for ((RULE) = (HEAD); \
(RULE) != NULL && ((NEXT) = next_rule_in_list(RULE), true); \
(RULE) = (NEXT))
static struct cls_rule *next_rule_in_list__(struct cls_rule *);
static struct cls_rule *next_rule_in_list(struct cls_rule *);
static struct cls_table *
cls_table_from_hmap_node(const struct hmap_node *node)
{
return node ? CONTAINER_OF(node, struct cls_table, hmap_node) : NULL;
}
/* Converts the flow in 'flow' into a cls_rule in 'rule', with the given
* 'wildcards' and 'priority'. */
void
cls_rule_init(const struct flow *flow, const struct flow_wildcards *wildcards,
unsigned int priority, struct cls_rule *rule)
{
rule->flow = *flow;
rule->wc = *wildcards;
rule->priority = priority;
cls_rule_zero_wildcarded_fields(rule);
}
/* Converts the flow in 'flow' into an exact-match cls_rule in 'rule', with the
* given 'priority'. (For OpenFlow 1.0, exact-match rule are always highest
* priority, so 'priority' should be at least 65535.) */
void
cls_rule_init_exact(const struct flow *flow,
unsigned int priority, struct cls_rule *rule)
{
rule->flow = *flow;
rule->flow.priority = 0;
flow_wildcards_init_exact(&rule->wc);
rule->priority = priority;
}
/* Initializes 'rule' as a "catch-all" rule that matches every packet, with
* priority 'priority'. */
void
cls_rule_init_catchall(struct cls_rule *rule, unsigned int priority)
{
memset(&rule->flow, 0, sizeof rule->flow);
flow_wildcards_init_catchall(&rule->wc);
rule->priority = priority;
}
/* For each bit or field wildcarded in 'rule', sets the corresponding bit or
* field in 'flow' to all-0-bits. It is important to maintain this invariant
* in a clr_rule that might be inserted into a classifier.
*
* It is never necessary to call this function directly for a cls_rule that is
* initialized or modified only by cls_rule_*() functions. It is useful to
* restore the invariant in a cls_rule whose 'wc' member is modified by hand.
*/
void
cls_rule_zero_wildcarded_fields(struct cls_rule *rule)
{
flow_zero_wildcards(&rule->flow, &rule->wc);
}
void
cls_rule_set_reg(struct cls_rule *rule, unsigned int reg_idx, uint32_t value)
{
cls_rule_set_reg_masked(rule, reg_idx, value, UINT32_MAX);
}
void
cls_rule_set_reg_masked(struct cls_rule *rule, unsigned int reg_idx,
uint32_t value, uint32_t mask)
{
assert(reg_idx < FLOW_N_REGS);
flow_wildcards_set_reg_mask(&rule->wc, reg_idx, mask);
rule->flow.regs[reg_idx] = value & mask;
}
void
cls_rule_set_tun_id(struct cls_rule *rule, ovs_be64 tun_id)
{
cls_rule_set_tun_id_masked(rule, tun_id, htonll(UINT64_MAX));
}
void
cls_rule_set_tun_id_masked(struct cls_rule *rule,
ovs_be64 tun_id, ovs_be64 mask)
{
rule->wc.tun_id_mask = mask;
rule->flow.tun_id = tun_id & mask;
}
void
cls_rule_set_in_port(struct cls_rule *rule, uint16_t ofp_port)
{
rule->wc.wildcards &= ~FWW_IN_PORT;
rule->flow.in_port = ofp_port;
}
void
cls_rule_set_dl_type(struct cls_rule *rule, ovs_be16 dl_type)
{
rule->wc.wildcards &= ~FWW_DL_TYPE;
rule->flow.dl_type = dl_type;
}
void
cls_rule_set_dl_src(struct cls_rule *rule, const uint8_t dl_src[ETH_ADDR_LEN])
{
rule->wc.wildcards &= ~FWW_DL_SRC;
memcpy(rule->flow.dl_src, dl_src, ETH_ADDR_LEN);
}
/* Modifies 'rule' so that the Ethernet address must match 'dl_dst' exactly. */
void
cls_rule_set_dl_dst(struct cls_rule *rule, const uint8_t dl_dst[ETH_ADDR_LEN])
{
rule->wc.wildcards &= ~(FWW_DL_DST | FWW_ETH_MCAST);
memcpy(rule->flow.dl_dst, dl_dst, ETH_ADDR_LEN);
}
/* Modifies 'rule' so that the Ethernet address must match 'dl_dst' after each
* byte is ANDed with the appropriate byte in 'mask'.
*
* This function will assert-fail if 'mask' is invalid. Only 'mask' values
* accepted by flow_wildcards_is_dl_dst_mask_valid() are allowed. */
void
cls_rule_set_dl_dst_masked(struct cls_rule *rule,
const uint8_t dl_dst[ETH_ADDR_LEN],
const uint8_t mask[ETH_ADDR_LEN])
{
flow_wildcards_t *wc = &rule->wc.wildcards;
size_t i;
*wc = flow_wildcards_set_dl_dst_mask(*wc, mask);
for (i = 0; i < ETH_ADDR_LEN; i++) {
rule->flow.dl_dst[i] = dl_dst[i] & mask[i];
}
}
void
cls_rule_set_dl_tci(struct cls_rule *rule, ovs_be16 tci)
{
cls_rule_set_dl_tci_masked(rule, tci, htons(0xffff));
}
void
cls_rule_set_dl_tci_masked(struct cls_rule *rule, ovs_be16 tci, ovs_be16 mask)
{
rule->flow.vlan_tci = tci & mask;
rule->wc.vlan_tci_mask = mask;
}
/* Modifies 'rule' so that the VLAN VID is wildcarded. If the PCP is already
* wildcarded, then 'rule' will match a packet regardless of whether it has an
* 802.1Q header or not. */
void
cls_rule_set_any_vid(struct cls_rule *rule)
{
if (rule->wc.vlan_tci_mask & htons(VLAN_PCP_MASK)) {
rule->wc.vlan_tci_mask &= ~htons(VLAN_VID_MASK);
rule->flow.vlan_tci &= ~htons(VLAN_VID_MASK);
} else {
cls_rule_set_dl_tci_masked(rule, htons(0), htons(0));
}
}
/* Modifies 'rule' depending on 'dl_vlan':
*
* - If 'dl_vlan' is htons(OFP_VLAN_NONE), makes 'rule' match only packets
* without an 802.1Q header.
*
* - Otherwise, makes 'rule' match only packets with an 802.1Q header whose
* VID equals the low 12 bits of 'dl_vlan'.
*/
void
cls_rule_set_dl_vlan(struct cls_rule *rule, ovs_be16 dl_vlan)
{
if (dl_vlan == htons(OFP_VLAN_NONE)) {
cls_rule_set_dl_tci(rule, htons(0));
} else {
dl_vlan &= htons(VLAN_VID_MASK);
rule->flow.vlan_tci &= ~htons(VLAN_VID_MASK);
rule->flow.vlan_tci |= htons(VLAN_CFI) | dl_vlan;
rule->wc.vlan_tci_mask |= htons(VLAN_VID_MASK | VLAN_CFI);
}
}
/* Modifies 'rule' so that the VLAN PCP is wildcarded. If the VID is already
* wildcarded, then 'rule' will match a packet regardless of whether it has an
* 802.1Q header or not. */
void
cls_rule_set_any_pcp(struct cls_rule *rule)
{
if (rule->wc.vlan_tci_mask & htons(VLAN_VID_MASK)) {
rule->wc.vlan_tci_mask &= ~htons(VLAN_PCP_MASK);
rule->flow.vlan_tci &= ~htons(VLAN_PCP_MASK);
} else {
cls_rule_set_dl_tci_masked(rule, htons(0), htons(0));
}
}
/* Modifies 'rule' so that it matches only packets with an 802.1Q header whose
* PCP equals the low 3 bits of 'dl_vlan_pcp'. */
void
cls_rule_set_dl_vlan_pcp(struct cls_rule *rule, uint8_t dl_vlan_pcp)
{
dl_vlan_pcp &= 0x07;
rule->flow.vlan_tci &= ~htons(VLAN_PCP_MASK);
rule->flow.vlan_tci |= htons((dl_vlan_pcp << VLAN_PCP_SHIFT) | VLAN_CFI);
rule->wc.vlan_tci_mask |= htons(VLAN_CFI | VLAN_PCP_MASK);
}
void
cls_rule_set_tp_src(struct cls_rule *rule, ovs_be16 tp_src)
{
rule->wc.wildcards &= ~FWW_TP_SRC;
rule->flow.tp_src = tp_src;
}
void
cls_rule_set_tp_dst(struct cls_rule *rule, ovs_be16 tp_dst)
{
rule->wc.wildcards &= ~FWW_TP_DST;
rule->flow.tp_dst = tp_dst;
}
void
cls_rule_set_nw_proto(struct cls_rule *rule, uint8_t nw_proto)
{
rule->wc.wildcards &= ~FWW_NW_PROTO;
rule->flow.nw_proto = nw_proto;
}
void
cls_rule_set_nw_src(struct cls_rule *rule, ovs_be32 nw_src)
{
cls_rule_set_nw_src_masked(rule, nw_src, htonl(UINT32_MAX));
}
bool
cls_rule_set_nw_src_masked(struct cls_rule *rule, ovs_be32 ip, ovs_be32 mask)
{
if (flow_wildcards_set_nw_src_mask(&rule->wc, mask)) {
rule->flow.nw_src = ip & mask;
return true;
} else {
return false;
}
}
void
cls_rule_set_nw_dst(struct cls_rule *rule, ovs_be32 nw_dst)
{
cls_rule_set_nw_dst_masked(rule, nw_dst, htonl(UINT32_MAX));
}
bool
cls_rule_set_nw_dst_masked(struct cls_rule *rule, ovs_be32 ip, ovs_be32 mask)
{
if (flow_wildcards_set_nw_dst_mask(&rule->wc, mask)) {
rule->flow.nw_dst = ip & mask;
return true;
} else {
return false;
}
}
void
cls_rule_set_nw_dscp(struct cls_rule *rule, uint8_t nw_dscp)
{
rule->wc.tos_mask |= IP_DSCP_MASK;
rule->flow.tos &= ~IP_DSCP_MASK;
rule->flow.tos |= nw_dscp & IP_DSCP_MASK;
}
void
cls_rule_set_nw_ecn(struct cls_rule *rule, uint8_t nw_ecn)
{
rule->wc.tos_mask |= IP_ECN_MASK;
rule->flow.tos &= ~IP_ECN_MASK;
rule->flow.tos |= nw_ecn & IP_ECN_MASK;
}
void
cls_rule_set_frag(struct cls_rule *rule, uint8_t frag)
{
rule->wc.frag_mask |= FLOW_FRAG_MASK;
rule->flow.frag = frag;
}
void
cls_rule_set_frag_masked(struct cls_rule *rule, uint8_t frag, uint8_t mask)
{
rule->flow.frag = frag & mask;
rule->wc.frag_mask = mask;
}
void
cls_rule_set_icmp_type(struct cls_rule *rule, uint8_t icmp_type)
{
rule->wc.wildcards &= ~FWW_TP_SRC;
rule->flow.tp_src = htons(icmp_type);
}
void
cls_rule_set_icmp_code(struct cls_rule *rule, uint8_t icmp_code)
{
rule->wc.wildcards &= ~FWW_TP_DST;
rule->flow.tp_dst = htons(icmp_code);
}
void
cls_rule_set_arp_sha(struct cls_rule *rule, const uint8_t sha[ETH_ADDR_LEN])
{
rule->wc.wildcards &= ~FWW_ARP_SHA;
memcpy(rule->flow.arp_sha, sha, ETH_ADDR_LEN);
}
void
cls_rule_set_arp_tha(struct cls_rule *rule, const uint8_t tha[ETH_ADDR_LEN])
{
rule->wc.wildcards &= ~FWW_ARP_THA;
memcpy(rule->flow.arp_tha, tha, ETH_ADDR_LEN);
}
void
cls_rule_set_ipv6_src(struct cls_rule *rule, const struct in6_addr *src)
{
cls_rule_set_ipv6_src_masked(rule, src, &in6addr_exact);
}
bool
cls_rule_set_ipv6_src_masked(struct cls_rule *rule, const struct in6_addr *src,
const struct in6_addr *mask)
{
if (flow_wildcards_set_ipv6_src_mask(&rule->wc, mask)) {
rule->flow.ipv6_src = ipv6_addr_bitand(src, mask);
return true;
} else {
return false;
}
}
void
cls_rule_set_ipv6_dst(struct cls_rule *rule, const struct in6_addr *dst)
{
cls_rule_set_ipv6_dst_masked(rule, dst, &in6addr_exact);
}
bool
cls_rule_set_ipv6_dst_masked(struct cls_rule *rule, const struct in6_addr *dst,
const struct in6_addr *mask)
{
if (flow_wildcards_set_ipv6_dst_mask(&rule->wc, mask)) {
rule->flow.ipv6_dst = ipv6_addr_bitand(dst, mask);
return true;
} else {
return false;
}
}
void
cls_rule_set_ipv6_label(struct cls_rule *rule, ovs_be32 ipv6_label)
{
rule->wc.wildcards &= ~FWW_IPV6_LABEL;
rule->flow.ipv6_label = ipv6_label;
}
void
cls_rule_set_nd_target(struct cls_rule *rule, const struct in6_addr *target)
{
rule->wc.wildcards &= ~FWW_ND_TARGET;
rule->flow.nd_target = *target;
}
/* Returns true if 'a' and 'b' have the same priority, wildcard the same
* fields, and have the same values for fixed fields, otherwise false. */
bool
cls_rule_equal(const struct cls_rule *a, const struct cls_rule *b)
{
return (a->priority == b->priority
&& flow_wildcards_equal(&a->wc, &b->wc)
&& flow_equal(&a->flow, &b->flow));
}
/* Returns a hash value for the flow, wildcards, and priority in 'rule',
* starting from 'basis'. */
uint32_t
cls_rule_hash(const struct cls_rule *rule, uint32_t basis)
{
uint32_t h0 = flow_hash(&rule->flow, basis);
uint32_t h1 = flow_wildcards_hash(&rule->wc, h0);
return hash_int(rule->priority, h1);
}
static void
format_ip_netmask(struct ds *s, const char *name, ovs_be32 ip,
ovs_be32 netmask)
{
if (netmask) {
ds_put_format(s, "%s=", name);
ip_format_masked(ip, netmask, s);
ds_put_char(s, ',');
}
}
static void
format_ipv6_netmask(struct ds *s, const char *name,
const struct in6_addr *addr,
const struct in6_addr *netmask)
{
if (!ipv6_mask_is_any(netmask)) {
ds_put_format(s, "%s=", name);
print_ipv6_masked(s, addr, netmask);
ds_put_char(s, ',');
}
}
void
cls_rule_format(const struct cls_rule *rule, struct ds *s)
{
const struct flow_wildcards *wc = &rule->wc;
size_t start_len = s->length;
flow_wildcards_t w = wc->wildcards;
const struct flow *f = &rule->flow;
bool skip_type = false;
bool skip_proto = false;
int i;
BUILD_ASSERT_DECL(FLOW_WC_SEQ == 5);
if (rule->priority != OFP_DEFAULT_PRIORITY) {
ds_put_format(s, "priority=%d,", rule->priority);
}
if (!(w & FWW_DL_TYPE)) {
skip_type = true;
if (f->dl_type == htons(ETH_TYPE_IP)) {
if (!(w & FWW_NW_PROTO)) {
skip_proto = true;
if (f->nw_proto == IPPROTO_ICMP) {
ds_put_cstr(s, "icmp,");
} else if (f->nw_proto == IPPROTO_TCP) {
ds_put_cstr(s, "tcp,");
} else if (f->nw_proto == IPPROTO_UDP) {
ds_put_cstr(s, "udp,");
} else {
ds_put_cstr(s, "ip,");
skip_proto = false;
}
} else {
ds_put_cstr(s, "ip,");
}
} else if (f->dl_type == htons(ETH_TYPE_IPV6)) {
if (!(w & FWW_NW_PROTO)) {
skip_proto = true;
if (f->nw_proto == IPPROTO_ICMPV6) {
ds_put_cstr(s, "icmp6,");
} else if (f->nw_proto == IPPROTO_TCP) {
ds_put_cstr(s, "tcp6,");
} else if (f->nw_proto == IPPROTO_UDP) {
ds_put_cstr(s, "udp6,");
} else {
ds_put_cstr(s, "ipv6,");
skip_proto = false;
}
} else {
ds_put_cstr(s, "ipv6,");
}
} else if (f->dl_type == htons(ETH_TYPE_ARP)) {
ds_put_cstr(s, "arp,");
} else {
skip_type = false;
}
}
for (i = 0; i < FLOW_N_REGS; i++) {
switch (wc->reg_masks[i]) {
case 0:
break;
case UINT32_MAX:
ds_put_format(s, "reg%d=0x%"PRIx32",", i, f->regs[i]);
break;
default:
ds_put_format(s, "reg%d=0x%"PRIx32"/0x%"PRIx32",",
i, f->regs[i], wc->reg_masks[i]);
break;
}
}
switch (wc->tun_id_mask) {
case 0:
break;
case CONSTANT_HTONLL(UINT64_MAX):
ds_put_format(s, "tun_id=%#"PRIx64",", ntohll(f->tun_id));
break;
default:
ds_put_format(s, "tun_id=%#"PRIx64"/%#"PRIx64",",
ntohll(f->tun_id), ntohll(wc->tun_id_mask));
break;
}
if (!(w & FWW_IN_PORT)) {
ds_put_format(s, "in_port=%"PRIu16",", f->in_port);
}
if (wc->vlan_tci_mask) {
ovs_be16 vid_mask = wc->vlan_tci_mask & htons(VLAN_VID_MASK);
ovs_be16 pcp_mask = wc->vlan_tci_mask & htons(VLAN_PCP_MASK);
ovs_be16 cfi = wc->vlan_tci_mask & htons(VLAN_CFI);
if (cfi && f->vlan_tci & htons(VLAN_CFI)
&& (!vid_mask || vid_mask == htons(VLAN_VID_MASK))
&& (!pcp_mask || pcp_mask == htons(VLAN_PCP_MASK))
&& (vid_mask || pcp_mask)) {
if (vid_mask) {
ds_put_format(s, "dl_vlan=%"PRIu16",",
vlan_tci_to_vid(f->vlan_tci));
}
if (pcp_mask) {
ds_put_format(s, "dl_vlan_pcp=%d,",
vlan_tci_to_pcp(f->vlan_tci));
}
} else if (wc->vlan_tci_mask == htons(0xffff)) {
ds_put_format(s, "vlan_tci=0x%04"PRIx16",", ntohs(f->vlan_tci));
} else {
ds_put_format(s, "vlan_tci=0x%04"PRIx16"/0x%04"PRIx16",",
ntohs(f->vlan_tci), ntohs(wc->vlan_tci_mask));
}
}
if (!(w & FWW_DL_SRC)) {
ds_put_format(s, "dl_src="ETH_ADDR_FMT",", ETH_ADDR_ARGS(f->dl_src));
}
switch (w & (FWW_DL_DST | FWW_ETH_MCAST)) {
case 0:
ds_put_format(s, "dl_dst="ETH_ADDR_FMT",", ETH_ADDR_ARGS(f->dl_dst));
break;
case FWW_DL_DST:
ds_put_format(s, "dl_dst="ETH_ADDR_FMT"/01:00:00:00:00:00,",
ETH_ADDR_ARGS(f->dl_dst));
break;
case FWW_ETH_MCAST:
ds_put_format(s, "dl_dst="ETH_ADDR_FMT"/fe:ff:ff:ff:ff:ff,",
ETH_ADDR_ARGS(f->dl_dst));
break;
case FWW_DL_DST | FWW_ETH_MCAST:
break;
}
if (!skip_type && !(w & FWW_DL_TYPE)) {
ds_put_format(s, "dl_type=0x%04"PRIx16",", ntohs(f->dl_type));
}
if (f->dl_type == htons(ETH_TYPE_IPV6)) {
format_ipv6_netmask(s, "ipv6_src", &f->ipv6_src, &wc->ipv6_src_mask);
format_ipv6_netmask(s, "ipv6_dst", &f->ipv6_dst, &wc->ipv6_dst_mask);
if (!(w & FWW_IPV6_LABEL)) {
ds_put_format(s, "ipv6_label=0x%05"PRIx32",", ntohl(f->ipv6_label));
}
} else {
format_ip_netmask(s, "nw_src", f->nw_src, wc->nw_src_mask);
format_ip_netmask(s, "nw_dst", f->nw_dst, wc->nw_dst_mask);
}
if (!skip_proto && !(w & FWW_NW_PROTO)) {
if (f->dl_type == htons(ETH_TYPE_ARP)) {
ds_put_format(s, "arp_op=%"PRIu8",", f->nw_proto);
} else {
ds_put_format(s, "nw_proto=%"PRIu8",", f->nw_proto);
}
}
if (f->dl_type == htons(ETH_TYPE_ARP)) {
if (!(w & FWW_ARP_SHA)) {
ds_put_format(s, "arp_sha="ETH_ADDR_FMT",",
ETH_ADDR_ARGS(f->arp_sha));
}
if (!(w & FWW_ARP_THA)) {
ds_put_format(s, "arp_tha="ETH_ADDR_FMT",",
ETH_ADDR_ARGS(f->arp_tha));
}
}
if (wc->tos_mask & IP_DSCP_MASK) {
ds_put_format(s, "nw_tos=%"PRIu8",", f->tos & IP_DSCP_MASK);
}
if (wc->tos_mask & IP_ECN_MASK) {
ds_put_format(s, "nw_ecn=%"PRIu8",", f->tos & IP_ECN_MASK);
}
switch (wc->frag_mask) {
case FLOW_FRAG_ANY | FLOW_FRAG_LATER:
ds_put_format(s, "frag=%s,",
f->frag & FLOW_FRAG_ANY
? (f->frag & FLOW_FRAG_LATER ? "later" : "first")
: (f->frag & FLOW_FRAG_LATER ? "<error>" : "no"));
break;
case FLOW_FRAG_ANY:
ds_put_format(s, "frag=%s,",
f->frag & FLOW_FRAG_ANY ? "yes" : "no");
break;
case FLOW_FRAG_LATER:
ds_put_format(s, "frag=%s,",
f->frag & FLOW_FRAG_LATER ? "later" : "not_later");
break;
}
if (f->nw_proto == IPPROTO_ICMP) {
if (!(w & FWW_TP_SRC)) {
ds_put_format(s, "icmp_type=%"PRIu16",", ntohs(f->tp_src));
}
if (!(w & FWW_TP_DST)) {
ds_put_format(s, "icmp_code=%"PRIu16",", ntohs(f->tp_dst));
}
} else if (f->nw_proto == IPPROTO_ICMPV6) {
if (!(w & FWW_TP_SRC)) {
ds_put_format(s, "icmp_type=%"PRIu16",", ntohs(f->tp_src));
}
if (!(w & FWW_TP_DST)) {
ds_put_format(s, "icmp_code=%"PRIu16",", ntohs(f->tp_dst));
}
if (!(w & FWW_ND_TARGET)) {
ds_put_cstr(s, "nd_target=");
print_ipv6_addr(s, &f->nd_target);
ds_put_char(s, ',');
}
if (!(w & FWW_ARP_SHA)) {
ds_put_format(s, "nd_sll="ETH_ADDR_FMT",",
ETH_ADDR_ARGS(f->arp_sha));
}
if (!(w & FWW_ARP_THA)) {
ds_put_format(s, "nd_tll="ETH_ADDR_FMT",",
ETH_ADDR_ARGS(f->arp_tha));
}
} else {
if (!(w & FWW_TP_SRC)) {
ds_put_format(s, "tp_src=%"PRIu16",", ntohs(f->tp_src));
}
if (!(w & FWW_TP_DST)) {
ds_put_format(s, "tp_dst=%"PRIu16",", ntohs(f->tp_dst));
}
}
if (s->length > start_len && ds_last(s) == ',') {
s->length--;
}
}
/* Converts 'rule' to a string and returns the string. The caller must free
* the string (with free()). */
char *
cls_rule_to_string(const struct cls_rule *rule)
{
struct ds s = DS_EMPTY_INITIALIZER;
cls_rule_format(rule, &s);
return ds_steal_cstr(&s);
}
void
cls_rule_print(const struct cls_rule *rule)
{
char *s = cls_rule_to_string(rule);
puts(s);
free(s);
}
/* Initializes 'cls' as a classifier that initially contains no classification
* rules. */
void
classifier_init(struct classifier *cls)
{
cls->n_rules = 0;
hmap_init(&cls->tables);
}
/* Destroys 'cls'. Rules within 'cls', if any, are not freed; this is the
* caller's responsibility. */
void
classifier_destroy(struct classifier *cls)
{
if (cls) {
struct cls_table *table, *next_table;
HMAP_FOR_EACH_SAFE (table, next_table, hmap_node, &cls->tables) {
hmap_destroy(&table->rules);
hmap_remove(&cls->tables, &table->hmap_node);
free(table);
}
hmap_destroy(&cls->tables);
}
}
/* Returns true if 'cls' contains no classification rules, false otherwise. */
bool
classifier_is_empty(const struct classifier *cls)
{
return cls->n_rules == 0;
}
/* Returns the number of rules in 'classifier'. */
int
classifier_count(const struct classifier *cls)
{
return cls->n_rules;
}
/* Inserts 'rule' into 'cls'. Until 'rule' is removed from 'cls', the caller
* must not modify or free it.
*
* If 'cls' already contains an identical rule (including wildcards, values of
* fixed fields, and priority), replaces the old rule by 'rule' and returns the
* rule that was replaced. The caller takes ownership of the returned rule and
* is thus responsible for freeing it, etc., as necessary.
*
* Returns NULL if 'cls' does not contain a rule with an identical key, after
* inserting the new rule. In this case, no rules are displaced by the new
* rule, even rules that cannot have any effect because the new rule matches a
* superset of their flows and has higher priority. */
struct cls_rule *
classifier_replace(struct classifier *cls, struct cls_rule *rule)
{
struct cls_rule *old_rule;
struct cls_table *table;
table = find_table(cls, &rule->wc);
if (!table) {
table = insert_table(cls, &rule->wc);
}
old_rule = insert_rule(table, rule);
if (!old_rule) {
table->n_table_rules++;
cls->n_rules++;
}
return old_rule;
}
/* Inserts 'rule' into 'cls'. Until 'rule' is removed from 'cls', the caller
* must not modify or free it.
*
* 'cls' must not contain an identical rule (including wildcards, values of
* fixed fields, and priority). Use classifier_find_rule_exactly() to find
* such a rule. */
void
classifier_insert(struct classifier *cls, struct cls_rule *rule)
{
struct cls_rule *displaced_rule = classifier_replace(cls, rule);
assert(!displaced_rule);
}
/* Removes 'rule' from 'cls'. It is the caller's responsibility to free
* 'rule', if this is desirable. */
void
classifier_remove(struct classifier *cls, struct cls_rule *rule)
{
struct cls_rule *head;
struct cls_table *table;
table = find_table(cls, &rule->wc);
head = find_equal(table, &rule->flow, rule->hmap_node.hash);
if (head != rule) {
list_remove(&rule->list);
} else if (list_is_empty(&rule->list)) {
hmap_remove(&table->rules, &rule->hmap_node);
} else {
struct cls_rule *next = CONTAINER_OF(rule->list.next,
struct cls_rule, list);
list_remove(&rule->list);
hmap_replace(&table->rules, &rule->hmap_node, &next->hmap_node);
}
if (--table->n_table_rules == 0) {
destroy_table(cls, table);
}
cls->n_rules--;
}
/* Finds and returns the highest-priority rule in 'cls' that matches 'flow'.
* Returns a null pointer if no rules in 'cls' match 'flow'. If multiple rules
* of equal priority match 'flow', returns one arbitrarily. */
struct cls_rule *
classifier_lookup(const struct classifier *cls, const struct flow *flow)
{
struct cls_table *table;
struct cls_rule *best;
best = NULL;
HMAP_FOR_EACH (table, hmap_node, &cls->tables) {
struct cls_rule *rule = find_match(table, flow);
if (rule && (!best || rule->priority > best->priority)) {
best = rule;
}
}
return best;
}
/* Finds and returns a rule in 'cls' with exactly the same priority and
* matching criteria as 'target'. Returns a null pointer if 'cls' doesn't
* contain an exact match. */
struct cls_rule *
classifier_find_rule_exactly(const struct classifier *cls,
const struct cls_rule *target)
{
struct cls_rule *head, *rule;
struct cls_table *table;
table = find_table(cls, &target->wc);
if (!table) {
return NULL;
}
head = find_equal(table, &target->flow, flow_hash(&target->flow, 0));
FOR_EACH_RULE_IN_LIST (rule, head) {
if (target->priority >= rule->priority) {
return target->priority == rule->priority ? rule : NULL;
}
}
return NULL;
}
/* Checks if 'target' would overlap any other rule in 'cls'. Two rules are
* considered to overlap if both rules have the same priority and a packet
* could match both. */
bool
classifier_rule_overlaps(const struct classifier *cls,
const struct cls_rule *target)
{
struct cls_table *table;
HMAP_FOR_EACH (table, hmap_node, &cls->tables) {
struct flow_wildcards wc;
struct cls_rule *head;
flow_wildcards_combine(&wc, &target->wc, &table->wc);
HMAP_FOR_EACH (head, hmap_node, &table->rules) {
struct cls_rule *rule;
FOR_EACH_RULE_IN_LIST (rule, head) {
if (rule->priority == target->priority
&& flow_equal_except(&target->flow, &rule->flow, &wc)) {
return true;
}
}
}
}
return false;
}
/* Iteration. */
static bool
rule_matches(const struct cls_rule *rule, const struct cls_rule *target)
{
return (!target
|| flow_equal_except(&rule->flow, &target->flow, &target->wc));
}
static struct cls_rule *
search_table(const struct cls_table *table, const struct cls_rule *target)
{
if (!target || !flow_wildcards_has_extra(&table->wc, &target->wc)) {
struct cls_rule *rule;
HMAP_FOR_EACH (rule, hmap_node, &table->rules) {
if (rule_matches(rule, target)) {
return rule;
}
}
}
return NULL;
}
/* Initializes 'cursor' for iterating through 'cls' rules that exactly match
* 'target' or are more specific than 'target'. That is, a given 'rule'
* matches 'target' if, for every field:
*
* - 'target' and 'rule' specify the same (non-wildcarded) value for the
* field, or
*
* - 'target' wildcards the field,
*
* but not if:
*
* - 'target' and 'rule' specify different values for the field, or
*
* - 'target' specifies a value for the field but 'rule' wildcards it.
*
* Equivalently, the truth table for whether a field matches is:
*
* rule
*
* wildcard exact
* +---------+---------+
* t wild | yes | yes |
* a card | | |
* r +---------+---------+
* g exact | no |if values|
* e | |are equal|
* t +---------+---------+
*
* This is the matching rule used by OpenFlow 1.0 non-strict OFPT_FLOW_MOD
* commands and by OpenFlow 1.0 aggregate and flow stats.
*
* Ignores target->priority.
*
* 'target' may be NULL to iterate over every rule in 'cls'. */
void
cls_cursor_init(struct cls_cursor *cursor, const struct classifier *cls,
const struct cls_rule *target)
{
cursor->cls = cls;
cursor->target = target;
}
/* Returns the first matching cls_rule in 'cursor''s iteration, or a null
* pointer if there are no matches. */
struct cls_rule *
cls_cursor_first(struct cls_cursor *cursor)
{
struct cls_table *table;
for (table = classifier_first_table(cursor->cls); table;
table = classifier_next_table(cursor->cls, table)) {
struct cls_rule *rule = search_table(table, cursor->target);
if (rule) {
cursor->table = table;
return rule;
}
}
return NULL;
}
/* Returns the next matching cls_rule in 'cursor''s iteration, or a null
* pointer if there are no more matches. */
struct cls_rule *
cls_cursor_next(struct cls_cursor *cursor, struct cls_rule *rule)
{
const struct cls_table *table;
struct cls_rule *next;
next = next_rule_in_list__(rule);
if (next->priority < rule->priority) {
return next;
}
/* 'next' is the head of the list, that is, the rule that is included in
* the table's hmap. (This is important when the classifier contains rules
* that differ only in priority.) */
rule = next;
HMAP_FOR_EACH_CONTINUE (rule, hmap_node, &cursor->table->rules) {
if (rule_matches(rule, cursor->target)) {
return rule;
}
}
for (table = classifier_next_table(cursor->cls, cursor->table); table;
table = classifier_next_table(cursor->cls, table)) {
rule = search_table(table, cursor->target);
if (rule) {
cursor->table = table;
return rule;
}
}
return NULL;
}
static struct cls_table *
find_table(const struct classifier *cls, const struct flow_wildcards *wc)
{
struct cls_table *table;
HMAP_FOR_EACH_IN_BUCKET (table, hmap_node, flow_wildcards_hash(wc, 0),
&cls->tables) {
if (flow_wildcards_equal(wc, &table->wc)) {
return table;
}
}
return NULL;
}
static struct cls_table *
insert_table(struct classifier *cls, const struct flow_wildcards *wc)
{
struct cls_table *table;
table = xzalloc(sizeof *table);
hmap_init(&table->rules);
table->wc = *wc;
hmap_insert(&cls->tables, &table->hmap_node, flow_wildcards_hash(wc, 0));
return table;
}
static struct cls_table *
classifier_first_table(const struct classifier *cls)
{
return cls_table_from_hmap_node(hmap_first(&cls->tables));
}
static struct cls_table *
classifier_next_table(const struct classifier *cls,
const struct cls_table *table)
{
return cls_table_from_hmap_node(hmap_next(&cls->tables,
&table->hmap_node));
}
static void
destroy_table(struct classifier *cls, struct cls_table *table)
{
hmap_remove(&cls->tables, &table->hmap_node);
hmap_destroy(&table->rules);
free(table);
}
static struct cls_rule *
find_match(const struct cls_table *table, const struct flow *flow)
{
struct cls_rule *rule;
struct flow f;
f = *flow;
flow_zero_wildcards(&f, &table->wc);
HMAP_FOR_EACH_WITH_HASH (rule, hmap_node, flow_hash(&f, 0),
&table->rules) {
if (flow_equal(&f, &rule->flow)) {
return rule;
}
}
return NULL;
}
static struct cls_rule *
find_equal(struct cls_table *table, const struct flow *flow, uint32_t hash)
{
struct cls_rule *head;
HMAP_FOR_EACH_WITH_HASH (head, hmap_node, hash, &table->rules) {
if (flow_equal(&head->flow, flow)) {
return head;
}
}
return NULL;
}
static struct cls_rule *
insert_rule(struct cls_table *table, struct cls_rule *new)
{
struct cls_rule *head;
new->hmap_node.hash = flow_hash(&new->flow, 0);
head = find_equal(table, &new->flow, new->hmap_node.hash);
if (!head) {
hmap_insert(&table->rules, &new->hmap_node, new->hmap_node.hash);
list_init(&new->list);
return NULL;
} else {
/* Scan the list for the insertion point that will keep the list in
* order of decreasing priority. */
struct cls_rule *rule;
FOR_EACH_RULE_IN_LIST (rule, head) {
if (new->priority >= rule->priority) {
if (rule == head) {
/* 'new' is the new highest-priority flow in the list. */
hmap_replace(&table->rules,
&rule->hmap_node, &new->hmap_node);
}
if (new->priority == rule->priority) {
list_replace(&new->list, &rule->list);
return rule;
} else {
list_insert(&rule->list, &new->list);
return NULL;
}
}
}
/* Insert 'new' at the end of the list. */
list_push_back(&head->list, &new->list);
return NULL;
}
}
static struct cls_rule *
next_rule_in_list__(struct cls_rule *rule)
{
struct cls_rule *next = OBJECT_CONTAINING(rule->list.next, next, list);
return next;
}
static struct cls_rule *
next_rule_in_list(struct cls_rule *rule)
{
struct cls_rule *next = next_rule_in_list__(rule);
return next->priority < rule->priority ? next : NULL;
}
static bool
ipv6_equal_except(const struct in6_addr *a, const struct in6_addr *b,
const struct in6_addr *mask)
{
int i;
#ifdef s6_addr32
for (i=0; i<4; i++) {
if ((a->s6_addr32[i] ^ b->s6_addr32[i]) & mask->s6_addr32[i]) {
return false;
}
}
#else
for (i=0; i<16; i++) {
if ((a->s6_addr[i] ^ b->s6_addr[i]) & mask->s6_addr[i]) {
return false;
}
}
#endif
return true;
}
static bool
flow_equal_except(const struct flow *a, const struct flow *b,
const struct flow_wildcards *wildcards)
{
const flow_wildcards_t wc = wildcards->wildcards;
int i;
BUILD_ASSERT_DECL(FLOW_WC_SEQ == 5);
for (i = 0; i < FLOW_N_REGS; i++) {
if ((a->regs[i] ^ b->regs[i]) & wildcards->reg_masks[i]) {
return false;
}
}
return (!((a->tun_id ^ b->tun_id) & wildcards->tun_id_mask)
&& !((a->nw_src ^ b->nw_src) & wildcards->nw_src_mask)
&& !((a->nw_dst ^ b->nw_dst) & wildcards->nw_dst_mask)
&& (wc & FWW_IN_PORT || a->in_port == b->in_port)
&& !((a->vlan_tci ^ b->vlan_tci) & wildcards->vlan_tci_mask)
&& (wc & FWW_DL_TYPE || a->dl_type == b->dl_type)
&& (wc & FWW_TP_SRC || a->tp_src == b->tp_src)
&& (wc & FWW_TP_DST || a->tp_dst == b->tp_dst)
&& (wc & FWW_DL_SRC || eth_addr_equals(a->dl_src, b->dl_src))
&& (wc & FWW_DL_DST
|| (!((a->dl_dst[0] ^ b->dl_dst[0]) & 0xfe)
&& a->dl_dst[1] == b->dl_dst[1]
&& a->dl_dst[2] == b->dl_dst[2]
&& a->dl_dst[3] == b->dl_dst[3]
&& a->dl_dst[4] == b->dl_dst[4]
&& a->dl_dst[5] == b->dl_dst[5]))
&& (wc & FWW_ETH_MCAST
|| !((a->dl_dst[0] ^ b->dl_dst[0]) & 0x01))
&& (wc & FWW_NW_PROTO || a->nw_proto == b->nw_proto)
&& !((a->tos ^ b->tos) & wildcards->tos_mask)
&& !((a->frag ^ b->frag) & wildcards->frag_mask)
&& (wc & FWW_ARP_SHA || eth_addr_equals(a->arp_sha, b->arp_sha))
&& (wc & FWW_ARP_THA || eth_addr_equals(a->arp_tha, b->arp_tha))
&& (wc & FWW_IPV6_LABEL || a->ipv6_label == b->ipv6_label)
&& ipv6_equal_except(&a->ipv6_src, &b->ipv6_src,
&wildcards->ipv6_src_mask)
&& ipv6_equal_except(&a->ipv6_dst, &b->ipv6_dst,
&wildcards->ipv6_dst_mask)
&& (wc & FWW_ND_TARGET
|| ipv6_addr_equals(&a->nd_target, &b->nd_target)));
}
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