1 /* Copyright (c) 2008 The Board of Trustees of The Leland Stanford
4 * We are making the OpenFlow specification and associated documentation
5 * (Software) available for public use and benefit with the expectation
6 * that others will use, modify and enhance the Software and contribute
7 * those enhancements back to the community. However, since we would
8 * like to make the Software available for broadest use, with as few
9 * restrictions as possible permission is hereby granted, free of
10 * charge, to any person obtaining a copy of this Software to deal in
11 * the Software under the copyrights without restriction, including
12 * without limitation the rights to use, copy, modify, merge, publish,
13 * distribute, sublicense, and/or sell copies of the Software, and to
14 * permit persons to whom the Software is furnished to do so, subject to
15 * the following conditions:
17 * The above copyright notice and this permission notice shall be
18 * included in all copies or substantial portions of the Software.
20 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
21 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
22 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
23 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
24 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
25 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
26 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
29 * The name and trademarks of copyright holder(s) may NOT be used in
30 * advertising or publicity pertaining to the Software or any
31 * derivatives without specific, written prior permission.
33 #include <sys/types.h>
36 #include <netinet/in.h>
46 #define THIS_MODULE VLM_flow
49 flow_extract(struct buffer *packet, uint16_t in_port, struct flow *flow)
51 struct buffer b = *packet;
52 struct eth_header *eth;
54 if (b.size < ETH_TOTAL_MIN) {
55 VLOG_WARN("packet length %d less than minimum size %d",
56 b.size, ETH_TOTAL_MIN);
59 memset(flow, 0, sizeof *flow);
60 flow->in_port = htons(in_port);
66 eth = buffer_at(&b, 0, sizeof *eth);
68 buffer_pull(&b, ETH_HEADER_LEN);
69 if (ntohs(eth->eth_type) >= OFP_DL_TYPE_ETH2_CUTOFF) {
70 /* This is an Ethernet II frame */
71 flow->dl_type = eth->eth_type;
73 /* This is an 802.2 frame */
74 struct llc_snap_header *h = buffer_at(&b, 0, sizeof *h);
78 if (h->llc.llc_dsap == LLC_DSAP_SNAP
79 && h->llc.llc_ssap == LLC_SSAP_SNAP
80 && h->llc.llc_cntl == LLC_CNTL_SNAP
81 && !memcmp(h->snap.snap_org, SNAP_ORG_ETHERNET,
82 sizeof h->snap.snap_org)) {
83 flow->dl_type = h->snap.snap_type;
84 buffer_pull(&b, sizeof *h);
86 flow->dl_type = OFP_DL_TYPE_NOT_ETH_TYPE;
87 buffer_pull(&b, sizeof(struct llc_header));
91 /* Check for a VLAN tag */
92 if (flow->dl_type != htons(ETH_TYPE_VLAN)) {
93 flow->dl_vlan = htons(OFP_VLAN_NONE);
95 struct vlan_header *vh = buffer_at(&b, 0, sizeof *vh);
96 flow->dl_type = vh->vlan_next_type;
97 flow->dl_vlan = vh->vlan_tci & htons(VLAN_VID);
98 buffer_pull(&b, sizeof *vh);
100 memcpy(flow->dl_src, eth->eth_src, ETH_ADDR_LEN);
101 memcpy(flow->dl_dst, eth->eth_dst, ETH_ADDR_LEN);
104 if (flow->dl_type == htons(ETH_TYPE_IP)) {
105 const struct ip_header *nh = buffer_at(&b, 0, sizeof *nh);
107 int ip_len = IP_IHL(nh->ip_ihl_ver) * 4;
108 if (ip_len < IP_HEADER_LEN) {
112 flow->nw_src = nh->ip_src;
113 flow->nw_dst = nh->ip_dst;
114 flow->nw_proto = nh->ip_proto;
115 if (flow->nw_proto == IP_TYPE_TCP
116 || flow->nw_proto == IP_TYPE_UDP) {
117 const struct udp_header *th;
118 th = packet->l4 = buffer_at(&b, ip_len, sizeof *th);
120 flow->tp_src = th->udp_src;
121 flow->tp_dst = th->udp_dst;
123 /* Avoid tricking other code into thinking that this
124 * packet has an L4 header. */
129 } else if (flow->dl_type == htons(ETH_TYPE_ARP)) {
130 const struct arp_eth_header *ah = buffer_at(&b, 0, sizeof *ah);
131 if (ah && ah->ar_hrd == htons(ARP_HRD_ETHERNET)
132 && ah->ar_pro == htons(ARP_PRO_IP)
133 && ah->ar_hln == ETH_ADDR_LEN
134 && ah->ar_pln == sizeof flow->nw_src)
136 /* check if sha/tha match dl_src/dl_dst? */
137 flow->nw_src = ah->ar_spa;
138 flow->nw_dst = ah->ar_tpa;
145 flow_print(FILE *stream, const struct flow *flow)
148 "port%04x:vlan%04x mac"MAC_FMT"->"MAC_FMT" "
149 "proto%04x ip"IP_FMT"->"IP_FMT" port%d->%d",
150 ntohs(flow->in_port), ntohs(flow->dl_vlan),
151 MAC_ARGS(flow->dl_src), MAC_ARGS(flow->dl_dst),
152 ntohs(flow->dl_type),
153 IP_ARGS(&flow->nw_src), IP_ARGS(&flow->nw_dst),
154 ntohs(flow->tp_src), ntohs(flow->tp_dst));
158 flow_compare(const struct flow *a, const struct flow *b)
160 return memcmp(a, b, sizeof *a);
164 flow_hash(const struct flow *flow, uint32_t basis)
166 return hash_fnv(flow, sizeof *flow, basis);