Files
openflow/lib/flow.c
T
Justin Pettit 06e22ff0fe Modify VLAN actions to support setting both VID and priority.
Stripping VLANs is now done through the OFPAT_STRIP_VLAN action (i.e., you
don't specify a magic value in the generirc VLAN action).  Also, it is now
possible to modify the priority bits associated with the VLAN tag through
the OFPAT_SET_VLAN_PCP action.  The OFPAT_SET_DL_VLAN has been renamed to
OFPAT_SET_VLAN_VID.
2008-09-25 15:00:38 -07:00

218 lines
7.5 KiB
C

/* Copyright (c) 2008 The Board of Trustees of The Leland Stanford
* Junior University
*
* We are making the OpenFlow specification and associated documentation
* (Software) available for public use and benefit with the expectation
* that others will use, modify and enhance the Software and contribute
* those enhancements back to the community. However, since we would
* like to make the Software available for broadest use, with as few
* restrictions as possible permission is hereby granted, free of
* charge, to any person obtaining a copy of this Software to deal in
* the Software under the copyrights without restriction, including
* without limitation the rights to use, copy, modify, merge, publish,
* distribute, sublicense, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so, subject to
* the following conditions:
*
* The above copyright notice and this permission notice shall be
* included in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
* BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
* ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*
* The name and trademarks of copyright holder(s) may NOT be used in
* advertising or publicity pertaining to the Software or any
* derivatives without specific, written prior permission.
*/
#include <config.h>
#include <sys/types.h>
#include "flow.h"
#include <inttypes.h>
#include <netinet/in.h>
#include <string.h>
#include "hash.h"
#include "ofpbuf.h"
#include "openflow.h"
#include "packets.h"
#include "vlog.h"
#define THIS_MODULE VLM_flow
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 eth_header *
pull_eth(struct ofpbuf *packet)
{
return ofpbuf_try_pull(packet, ETH_HEADER_LEN);
}
static struct vlan_header *
pull_vlan(struct ofpbuf *packet)
{
return ofpbuf_try_pull(packet, VLAN_HEADER_LEN);
}
/* Returns 1 if 'packet' is an IP fragment, 0 otherwise. */
int
flow_extract(struct ofpbuf *packet, uint16_t in_port, struct flow *flow)
{
struct ofpbuf b = *packet;
struct eth_header *eth;
int retval = 0;
if (b.size < ETH_TOTAL_MIN) {
/* This message is not too useful since there are various ways that we
* can end up with runt frames, e.g. frames that only ever passed
* through virtual network devices and never touched a physical
* Ethernet. */
static struct vlog_rate_limit rl = VLOG_RATE_LIMIT_INIT(5, 60);
VLOG_DBG_RL(&rl, "packet length %zu less than minimum size %d",
b.size, ETH_TOTAL_MIN);
}
memset(flow, 0, sizeof *flow);
flow->dl_vlan = htons(OFP_VLAN_NONE);
flow->in_port = htons(in_port);
packet->l2 = b.data;
packet->l3 = NULL;
packet->l4 = NULL;
packet->l7 = NULL;
eth = pull_eth(&b);
if (eth) {
if (ntohs(eth->eth_type) >= OFP_DL_TYPE_ETH2_CUTOFF) {
/* This is an Ethernet II frame */
flow->dl_type = eth->eth_type;
} else {
/* This is an 802.2 frame */
struct llc_snap_header *h = ofpbuf_at(&b, 0, sizeof *h);
if (h == NULL) {
return 0;
}
if (h->llc.llc_dsap == LLC_DSAP_SNAP
&& h->llc.llc_ssap == LLC_SSAP_SNAP
&& h->llc.llc_cntl == LLC_CNTL_SNAP
&& !memcmp(h->snap.snap_org, SNAP_ORG_ETHERNET,
sizeof h->snap.snap_org)) {
flow->dl_type = h->snap.snap_type;
ofpbuf_pull(&b, sizeof *h);
} else {
flow->dl_type = htons(OFP_DL_TYPE_NOT_ETH_TYPE);
ofpbuf_pull(&b, sizeof(struct llc_header));
}
}
/* Check for a VLAN tag */
if (flow->dl_type == htons(ETH_TYPE_VLAN)) {
struct vlan_header *vh = pull_vlan(&b);
if (vh) {
flow->dl_type = vh->vlan_next_type;
flow->dl_vlan = vh->vlan_tci & htons(VLAN_VID_MASK);
}
}
memcpy(flow->dl_src, eth->eth_src, ETH_ADDR_LEN);
memcpy(flow->dl_dst, eth->eth_dst, ETH_ADDR_LEN);
packet->l3 = b.data;
if (flow->dl_type == htons(ETH_TYPE_IP)) {
const struct ip_header *nh = pull_ip(&b);
if (nh) {
flow->nw_src = nh->ip_src;
flow->nw_dst = nh->ip_dst;
flow->nw_proto = nh->ip_proto;
packet->l4 = b.data;
if (!IP_IS_FRAGMENT(nh->ip_frag_off)) {
if (flow->nw_proto == IP_TYPE_TCP) {
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;
} else {
/* Avoid tricking other code into thinking that
* this packet has an L4 header. */
flow->nw_proto = 0;
}
} else if (flow->nw_proto == IP_TYPE_UDP) {
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;
} else {
/* Avoid tricking other code into thinking that
* this packet has an L4 header. */
flow->nw_proto = 0;
}
}
} else {
retval = 1;
}
}
}
}
return retval;
}
void
flow_print(FILE *stream, const struct flow *flow)
{
fprintf(stream,
"port%04x:vlan%04x mac"ETH_ADDR_FMT"->"ETH_ADDR_FMT" "
"proto%04x ip"IP_FMT"->"IP_FMT" port%d->%d",
ntohs(flow->in_port), ntohs(flow->dl_vlan),
ETH_ADDR_ARGS(flow->dl_src), ETH_ADDR_ARGS(flow->dl_dst),
ntohs(flow->dl_type),
IP_ARGS(&flow->nw_src), IP_ARGS(&flow->nw_dst),
ntohs(flow->tp_src), ntohs(flow->tp_dst));
}
int
flow_compare(const struct flow *a, const struct flow *b)
{
return memcmp(a, b, sizeof *a);
}
unsigned long int
flow_hash(const struct flow *flow, uint32_t basis)
{
return hash_fnv(flow, sizeof *flow, basis);
}