2 * Copyright (c) 2008, 2009, 2010 Nicira Networks.
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at:
8 * http://www.apache.org/licenses/LICENSE-2.0
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
17 #include <sys/types.h>
20 #include <netinet/in.h>
23 #include "byte-order.h"
25 #include "dynamic-string.h"
28 #include "openflow/openflow.h"
29 #include "openvswitch/datapath-protocol.h"
31 #include "unaligned.h"
34 VLOG_DEFINE_THIS_MODULE(flow);
36 static struct arp_eth_header *
37 pull_arp(struct ofpbuf *packet)
39 return ofpbuf_try_pull(packet, ARP_ETH_HEADER_LEN);
42 static struct ip_header *
43 pull_ip(struct ofpbuf *packet)
45 if (packet->size >= IP_HEADER_LEN) {
46 struct ip_header *ip = packet->data;
47 int ip_len = IP_IHL(ip->ip_ihl_ver) * 4;
48 if (ip_len >= IP_HEADER_LEN && packet->size >= ip_len) {
49 return ofpbuf_pull(packet, ip_len);
55 static struct tcp_header *
56 pull_tcp(struct ofpbuf *packet)
58 if (packet->size >= TCP_HEADER_LEN) {
59 struct tcp_header *tcp = packet->data;
60 int tcp_len = TCP_OFFSET(tcp->tcp_ctl) * 4;
61 if (tcp_len >= TCP_HEADER_LEN && packet->size >= tcp_len) {
62 return ofpbuf_pull(packet, tcp_len);
68 static struct udp_header *
69 pull_udp(struct ofpbuf *packet)
71 return ofpbuf_try_pull(packet, UDP_HEADER_LEN);
74 static struct icmp_header *
75 pull_icmp(struct ofpbuf *packet)
77 return ofpbuf_try_pull(packet, ICMP_HEADER_LEN);
81 parse_vlan(struct ofpbuf *b, struct flow *flow)
84 ovs_be16 eth_type; /* ETH_TYPE_VLAN */
88 if (b->size >= sizeof(struct qtag_prefix) + sizeof(ovs_be16)) {
89 struct qtag_prefix *qp = ofpbuf_pull(b, sizeof *qp);
90 flow->dl_vlan = qp->tci & htons(VLAN_VID_MASK);
91 flow->dl_vlan_pcp = vlan_tci_to_pcp(qp->tci);
96 parse_ethertype(struct ofpbuf *b)
98 struct llc_snap_header *llc;
101 proto = *(ovs_be16 *) ofpbuf_pull(b, sizeof proto);
102 if (ntohs(proto) >= ODP_DL_TYPE_ETH2_CUTOFF) {
106 if (b->size < sizeof *llc) {
107 return htons(ODP_DL_TYPE_NOT_ETH_TYPE);
111 if (llc->llc.llc_dsap != LLC_DSAP_SNAP
112 || llc->llc.llc_ssap != LLC_SSAP_SNAP
113 || llc->llc.llc_cntl != LLC_CNTL_SNAP
114 || memcmp(llc->snap.snap_org, SNAP_ORG_ETHERNET,
115 sizeof llc->snap.snap_org)) {
116 return htons(ODP_DL_TYPE_NOT_ETH_TYPE);
119 ofpbuf_pull(b, sizeof *llc);
120 return llc->snap.snap_type;
123 /* Initializes 'flow' members from 'packet', 'tun_id', and 'in_port.
124 * Initializes 'packet' header pointers as follows:
126 * - packet->l2 to the start of the Ethernet header.
128 * - packet->l3 to just past the Ethernet header, or just past the
129 * vlan_header if one is present, to the first byte of the payload of the
132 * - packet->l4 to just past the IPv4 header, if one is present and has a
133 * correct length, and otherwise NULL.
135 * - packet->l7 to just past the TCP or UDP or ICMP header, if one is
136 * present and has a correct length, and otherwise NULL.
139 flow_extract(struct ofpbuf *packet, ovs_be32 tun_id, uint16_t in_port,
142 struct ofpbuf b = *packet;
143 struct eth_header *eth;
146 COVERAGE_INC(flow_extract);
148 memset(flow, 0, sizeof *flow);
149 flow->tun_id = tun_id;
150 flow->in_port = in_port;
151 flow->dl_vlan = htons(OFP_VLAN_NONE);
158 if (b.size < sizeof *eth) {
164 memcpy(flow->dl_src, eth->eth_src, ETH_ADDR_LEN);
165 memcpy(flow->dl_dst, eth->eth_dst, ETH_ADDR_LEN);
167 /* dl_type, dl_vlan, dl_vlan_pcp. */
168 ofpbuf_pull(&b, ETH_ADDR_LEN * 2);
169 if (eth->eth_type == htons(ETH_TYPE_VLAN)) {
170 parse_vlan(&b, flow);
172 flow->dl_type = parse_ethertype(&b);
176 if (flow->dl_type == htons(ETH_TYPE_IP)) {
177 const struct ip_header *nh = pull_ip(&b);
179 flow->nw_src = get_unaligned_u32(&nh->ip_src);
180 flow->nw_dst = get_unaligned_u32(&nh->ip_dst);
181 flow->nw_tos = nh->ip_tos & IP_DSCP_MASK;
182 flow->nw_proto = nh->ip_proto;
184 if (!IP_IS_FRAGMENT(nh->ip_frag_off)) {
185 if (flow->nw_proto == IP_TYPE_TCP) {
186 const struct tcp_header *tcp = pull_tcp(&b);
188 flow->tp_src = tcp->tcp_src;
189 flow->tp_dst = tcp->tcp_dst;
192 } else if (flow->nw_proto == IP_TYPE_UDP) {
193 const struct udp_header *udp = pull_udp(&b);
195 flow->tp_src = udp->udp_src;
196 flow->tp_dst = udp->udp_dst;
199 } else if (flow->nw_proto == IP_TYPE_ICMP) {
200 const struct icmp_header *icmp = pull_icmp(&b);
202 flow->icmp_type = htons(icmp->icmp_type);
203 flow->icmp_code = htons(icmp->icmp_code);
211 } else if (flow->dl_type == htons(ETH_TYPE_ARP)) {
212 const struct arp_eth_header *arp = pull_arp(&b);
213 if (arp && arp->ar_hrd == htons(1)
214 && arp->ar_pro == htons(ETH_TYPE_IP)
215 && arp->ar_hln == ETH_ADDR_LEN
216 && arp->ar_pln == 4) {
217 /* We only match on the lower 8 bits of the opcode. */
218 if (ntohs(arp->ar_op) <= 0xff) {
219 flow->nw_proto = ntohs(arp->ar_op);
222 if ((flow->nw_proto == ARP_OP_REQUEST)
223 || (flow->nw_proto == ARP_OP_REPLY)) {
224 flow->nw_src = arp->ar_spa;
225 flow->nw_dst = arp->ar_tpa;
232 /* Extracts the flow stats for a packet. The 'flow' and 'packet'
233 * arguments must have been initialized through a call to flow_extract().
236 flow_extract_stats(const struct flow *flow, struct ofpbuf *packet,
237 struct odp_flow_stats *stats)
239 memset(stats, '\0', sizeof(*stats));
241 if ((flow->dl_type == htons(ETH_TYPE_IP)) && packet->l4) {
242 if ((flow->nw_proto == IP_TYPE_TCP) && packet->l7) {
243 struct tcp_header *tcp = packet->l4;
244 stats->tcp_flags = TCP_FLAGS(tcp->tcp_ctl);
248 stats->n_bytes = packet->size;
249 stats->n_packets = 1;
252 /* Extract 'flow' with 'wildcards' into the OpenFlow match structure
255 flow_to_match(const struct flow *flow, uint32_t wildcards,
256 bool tun_id_from_cookie, struct ofp_match *match)
258 if (!tun_id_from_cookie) {
259 wildcards &= OFPFW_ALL;
261 match->wildcards = htonl(wildcards);
263 match->in_port = htons(flow->in_port == ODPP_LOCAL ? OFPP_LOCAL
265 match->dl_vlan = flow->dl_vlan;
266 match->dl_vlan_pcp = flow->dl_vlan_pcp;
267 memcpy(match->dl_src, flow->dl_src, ETH_ADDR_LEN);
268 memcpy(match->dl_dst, flow->dl_dst, ETH_ADDR_LEN);
269 match->dl_type = flow->dl_type;
270 match->nw_src = flow->nw_src;
271 match->nw_dst = flow->nw_dst;
272 match->nw_tos = flow->nw_tos;
273 match->nw_proto = flow->nw_proto;
274 match->tp_src = flow->tp_src;
275 match->tp_dst = flow->tp_dst;
276 memset(match->pad1, '\0', sizeof match->pad1);
277 memset(match->pad2, '\0', sizeof match->pad2);
281 flow_from_match(const struct ofp_match *match, bool tun_id_from_cookie,
282 ovs_be64 cookie, struct flow *flow, uint32_t *flow_wildcards)
284 uint32_t wildcards = ntohl(match->wildcards);
286 flow->nw_src = match->nw_src;
287 flow->nw_dst = match->nw_dst;
288 if (tun_id_from_cookie && !(wildcards & NXFW_TUN_ID)) {
289 flow->tun_id = htonl(ntohll(cookie) >> 32);
291 wildcards |= NXFW_TUN_ID;
294 flow->in_port = (match->in_port == htons(OFPP_LOCAL) ? ODPP_LOCAL
295 : ntohs(match->in_port));
296 flow->dl_vlan = match->dl_vlan;
297 flow->dl_vlan_pcp = match->dl_vlan_pcp;
298 flow->dl_type = match->dl_type;
299 flow->tp_src = match->tp_src;
300 flow->tp_dst = match->tp_dst;
301 memcpy(flow->dl_src, match->dl_src, ETH_ADDR_LEN);
302 memcpy(flow->dl_dst, match->dl_dst, ETH_ADDR_LEN);
303 flow->nw_tos = match->nw_tos;
304 flow->nw_proto = match->nw_proto;
305 if (flow_wildcards) {
306 *flow_wildcards = wildcards;
311 flow_to_string(const struct flow *flow)
313 struct ds ds = DS_EMPTY_INITIALIZER;
314 flow_format(&ds, flow);
319 flow_format(struct ds *ds, const struct flow *flow)
321 ds_put_format(ds, "tunnel%08"PRIx32":in_port%04"PRIx16
322 ":vlan%"PRIu16":pcp%"PRIu8
323 " mac"ETH_ADDR_FMT"->"ETH_ADDR_FMT
327 " ip"IP_FMT"->"IP_FMT
328 " port%"PRIu16"->%"PRIu16,
331 ntohs(flow->dl_vlan),
333 ETH_ADDR_ARGS(flow->dl_src),
334 ETH_ADDR_ARGS(flow->dl_dst),
335 ntohs(flow->dl_type),
338 IP_ARGS(&flow->nw_src),
339 IP_ARGS(&flow->nw_dst),
341 ntohs(flow->tp_dst));
345 flow_print(FILE *stream, const struct flow *flow)
347 char *s = flow_to_string(flow);
352 /* flow_wildcards functions. */
354 /* Given the wildcard bit count in bits 'shift' through 'shift + 5' (inclusive)
355 * of 'wildcards', returns a 32-bit bit mask with a 1 in each bit that must
356 * match and a 0 in each bit that is wildcarded.
358 * The bits in 'wildcards' are in the format used in enum ofp_flow_wildcards: 0
359 * is exact match, 1 ignores the LSB, 2 ignores the 2 least-significant bits,
360 * ..., 32 and higher wildcard the entire field. This is the *opposite* of the
361 * usual convention where e.g. /24 indicates that 8 bits (not 24 bits) are
364 flow_nw_bits_to_mask(uint32_t wildcards, int shift)
366 wildcards = (wildcards >> shift) & 0x3f;
367 return wildcards < 32 ? htonl(~((1u << wildcards) - 1)) : 0;
370 /* Return 'wildcards' in "normal form":
372 * - Forces unknown bits to 0.
374 * - Forces nw_src and nw_dst masks greater than 32 to exactly 32.
376 static inline uint32_t
377 flow_wildcards_normalize(uint32_t wildcards)
379 wildcards &= wildcards & OVSFW_ALL;
380 if (wildcards & (0x20 << OFPFW_NW_SRC_SHIFT)) {
381 wildcards &= ~(0x1f << OFPFW_NW_SRC_SHIFT);
383 if (wildcards & (0x20 << OFPFW_NW_DST_SHIFT)) {
384 wildcards &= ~(0x1f << OFPFW_NW_DST_SHIFT);
389 /* Initializes 'wc' from 'wildcards', which may be any combination of the
390 * OFPFW_* and OVSFW_* wildcard bits. */
392 flow_wildcards_init(struct flow_wildcards *wc, uint32_t wildcards)
394 wc->wildcards = flow_wildcards_normalize(wildcards);
395 wc->nw_src_mask = flow_nw_bits_to_mask(wc->wildcards, OFPFW_NW_SRC_SHIFT);
396 wc->nw_dst_mask = flow_nw_bits_to_mask(wc->wildcards, OFPFW_NW_DST_SHIFT);
399 /* Initializes 'wc' as an exact-match set of wildcards; that is, 'wc' does not
400 * wildcard any bits or fields. */
402 flow_wildcards_init_exact(struct flow_wildcards *wc)
404 flow_wildcards_init(wc, 0);
407 static inline uint32_t
408 combine_nw_bits(uint32_t wb1, uint32_t wb2, int shift)
410 uint32_t sb1 = (wb1 >> shift) & 0x3f;
411 uint32_t sb2 = (wb2 >> shift) & 0x3f;
412 return MAX(sb1, sb2) << shift;
415 /* Initializes 'dst' as the combination of wildcards in 'src1' and 'src2'.
416 * That is, a bit or a field is wildcarded in 'dst' if it is wildcarded in
417 * 'src1' or 'src2' or both. */
419 flow_wildcards_combine(struct flow_wildcards *dst,
420 const struct flow_wildcards *src1,
421 const struct flow_wildcards *src2)
423 uint32_t wb1 = src1->wildcards;
424 uint32_t wb2 = src2->wildcards;
426 dst->wildcards = (wb1 | wb2) & ~(OFPFW_NW_SRC_MASK | OFPFW_NW_DST_MASK);
427 dst->wildcards |= combine_nw_bits(wb1, wb2, OFPFW_NW_SRC_SHIFT);
428 dst->wildcards |= combine_nw_bits(wb1, wb2, OFPFW_NW_DST_SHIFT);
429 dst->nw_src_mask = src1->nw_src_mask & src2->nw_src_mask;
430 dst->nw_dst_mask = src1->nw_dst_mask & src2->nw_dst_mask;
433 /* Returns a hash of the wildcards in 'wc'. */
435 flow_wildcards_hash(const struct flow_wildcards *wc)
437 /* There is no need to include nw_src_mask or nw_dst_mask because they do
438 * not add any information (they can be computed from wc->wildcards). */
439 return hash_int(wc->wildcards, 0);
442 /* Returns true if 'a' and 'b' represent the same wildcards, false if they are
445 flow_wildcards_equal(const struct flow_wildcards *a,
446 const struct flow_wildcards *b)
448 return a->wildcards == b->wildcards;
451 /* Returns true if at least one bit or field is wildcarded in 'a' but not in
452 * 'b', false otherwise. */
454 flow_wildcards_has_extra(const struct flow_wildcards *a,
455 const struct flow_wildcards *b)
457 #define OFPFW_NW_MASK (OFPFW_NW_SRC_MASK | OFPFW_NW_DST_MASK)
458 return ((a->wildcards & ~(b->wildcards | OFPFW_NW_MASK))
459 || (a->nw_src_mask & b->nw_src_mask) != b->nw_src_mask
460 || (a->nw_dst_mask & b->nw_dst_mask) != b->nw_dst_mask);
464 count_ones(ovs_be32 mask)
467 return __builtin_popcount(mask);
471 for (bits = 0; mask; bits++) {
480 set_nw_mask(struct flow_wildcards *wc, ovs_be32 mask,
481 ovs_be32 *maskp, int shift)
483 int wcbits = 32 - count_ones(mask);
484 if (flow_nw_bits_to_mask(wcbits, 0) == mask) {
485 wc->wildcards &= ~(0x3f << shift);
486 wc->wildcards |= wcbits << shift;
494 /* Sets the IP (or ARP) source wildcard mask to CIDR 'mask' (consisting of N
495 * high-order 1-bit and 32-N low-order 0-bits). Returns true if successful,
496 * false if 'mask' is not a CIDR mask. */
498 flow_wildcards_set_nw_src_mask(struct flow_wildcards *wc, ovs_be32 mask)
500 return set_nw_mask(wc, mask, &wc->nw_src_mask, OFPFW_NW_SRC_SHIFT);
503 /* Sets the IP (or ARP) destination wildcard mask to CIDR 'mask' (consisting of
504 * N high-order 1-bit and 32-N low-order 0-bits). Returns true if successful,
505 * false if 'mask' is not a CIDR mask. */
507 flow_wildcards_set_nw_dst_mask(struct flow_wildcards *wc, ovs_be32 mask)
509 return set_nw_mask(wc, mask, &wc->nw_dst_mask, OFPFW_NW_DST_SHIFT);