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.
19 #include <arpa/inet.h>
32 #include "openflow/openflow.h"
34 #include "poll-loop.h"
38 #define THIS_MODULE VLM_in_band
41 /* In-band control allows a single network to be used for OpenFlow
42 * traffic and other data traffic. Refer to ovs-vswitchd.conf(5) and
43 * secchan(8) for a description of configuring in-band control.
45 * This comment is an attempt to describe how in-band control works at a
46 * wire- and implementation-level. Correctly implementing in-band
47 * control has proven difficult due to its many subtleties, and has thus
48 * gone through many iterations. Please read through and understand the
49 * reasoning behind the chosen rules before making modifications.
51 * In Open vSwitch, in-band control is implemented as "hidden" flows (in that
52 * they are not visible through OpenFlow) and at a higher priority than
53 * wildcarded flows can be set up by through OpenFlow. This is done so that
54 * the OpenFlow controller cannot interfere with them and possibly break
55 * connectivity with its switches. It is possible to see all flows, including
56 * in-band ones, with the ovs-appctl "bridge/dump-flows" command.
58 * The Open vSwitch implementation of in-band control can hide traffic to
59 * arbitrary "remotes", where each remote is one TCP port on one IP address.
60 * Currently the remotes are automatically configured as the in-band OpenFlow
61 * controllers plus the OVSDB managers, if any. (The latter is a requirement
62 * because OVSDB managers are responsible for configuring OpenFlow controllers,
63 * so if the manager cannot be reached then OpenFlow cannot be reconfigured.)
65 * The following rules (with the OFPP_NORMAL action) are set up on any bridge
66 * that has any remotes:
68 * (a) DHCP requests sent from the local port.
69 * (b) ARP replies to the local port's MAC address.
70 * (c) ARP requests from the local port's MAC address.
72 * In-band also sets up the following rules for each unique next-hop MAC
73 * address for the remotes' IPs (the "next hop" is either the remote
74 * itself, if it is on a local subnet, or the gateway to reach the remote):
76 * (d) ARP replies to the next hop's MAC address.
77 * (e) ARP requests from the next hop's MAC address.
79 * In-band also sets up the following rules for each unique remote IP address:
81 * (f) ARP replies containing the remote's IP address as a target.
82 * (g) ARP requests containing the remote's IP address as a source.
84 * In-band also sets up the following rules for each unique remote (IP,port)
87 * (h) TCP traffic to the remote's IP and port.
88 * (i) TCP traffic from the remote's IP and port.
90 * The goal of these rules is to be as narrow as possible to allow a
91 * switch to join a network and be able to communicate with the
92 * remotes. As mentioned earlier, these rules have higher priority
93 * than the controller's rules, so if they are too broad, they may
94 * prevent the controller from implementing its policy. As such,
95 * in-band actively monitors some aspects of flow and packet processing
96 * so that the rules can be made more precise.
98 * In-band control monitors attempts to add flows into the datapath that
99 * could interfere with its duties. The datapath only allows exact
100 * match entries, so in-band control is able to be very precise about
101 * the flows it prevents. Flows that miss in the datapath are sent to
102 * userspace to be processed, so preventing these flows from being
103 * cached in the "fast path" does not affect correctness. The only type
104 * of flow that is currently prevented is one that would prevent DHCP
105 * replies from being seen by the local port. For example, a rule that
106 * forwarded all DHCP traffic to the controller would not be allowed,
107 * but one that forwarded to all ports (including the local port) would.
109 * As mentioned earlier, packets that miss in the datapath are sent to
110 * the userspace for processing. The userspace has its own flow table,
111 * the "classifier", so in-band checks whether any special processing
112 * is needed before the classifier is consulted. If a packet is a DHCP
113 * response to a request from the local port, the packet is forwarded to
114 * the local port, regardless of the flow table. Note that this requires
115 * L7 processing of DHCP replies to determine whether the 'chaddr' field
116 * matches the MAC address of the local port.
118 * It is interesting to note that for an L3-based in-band control
119 * mechanism, the majority of rules are devoted to ARP traffic. At first
120 * glance, some of these rules appear redundant. However, each serves an
121 * important role. First, in order to determine the MAC address of the
122 * remote side (controller or gateway) for other ARP rules, we must allow
123 * ARP traffic for our local port with rules (b) and (c). If we are
124 * between a switch and its connection to the remote, we have to
125 * allow the other switch's ARP traffic to through. This is done with
126 * rules (d) and (e), since we do not know the addresses of the other
127 * switches a priori, but do know the remote's or gateway's. Finally,
128 * if the remote is running in a local guest VM that is not reached
129 * through the local port, the switch that is connected to the VM must
130 * allow ARP traffic based on the remote's IP address, since it will
131 * not know the MAC address of the local port that is sending the traffic
132 * or the MAC address of the remote in the guest VM.
134 * With a few notable exceptions below, in-band should work in most
135 * network setups. The following are considered "supported' in the
136 * current implementation:
138 * - Locally Connected. The switch and remote are on the same
139 * subnet. This uses rules (a), (b), (c), (h), and (i).
141 * - Reached through Gateway. The switch and remote are on
142 * different subnets and must go through a gateway. This uses
143 * rules (a), (b), (c), (h), and (i).
145 * - Between Switch and Remote. This switch is between another
146 * switch and the remote, and we want to allow the other
147 * switch's traffic through. This uses rules (d), (e), (h), and
148 * (i). It uses (b) and (c) indirectly in order to know the MAC
149 * address for rules (d) and (e). Note that DHCP for the other
150 * switch will not work unless an OpenFlow controller explicitly lets this
151 * switch pass the traffic.
153 * - Between Switch and Gateway. This switch is between another
154 * switch and the gateway, and we want to allow the other switch's
155 * traffic through. This uses the same rules and logic as the
156 * "Between Switch and Remote" configuration described earlier.
158 * - Remote on Local VM. The remote is a guest VM on the
159 * system running in-band control. This uses rules (a), (b), (c),
162 * - Remote on Local VM with Different Networks. The remote
163 * is a guest VM on the system running in-band control, but the
164 * local port is not used to connect to the remote. For
165 * example, an IP address is configured on eth0 of the switch. The
166 * remote's VM is connected through eth1 of the switch, but an
167 * IP address has not been configured for that port on the switch.
168 * As such, the switch will use eth0 to connect to the remote,
169 * and eth1's rules about the local port will not work. In the
170 * example, the switch attached to eth0 would use rules (a), (b),
171 * (c), (h), and (i) on eth0. The switch attached to eth1 would use
172 * rules (f), (g), (h), and (i).
174 * The following are explicitly *not* supported by in-band control:
176 * - Specify Remote by Name. Currently, the remote must be
177 * identified by IP address. A naive approach would be to permit
178 * all DNS traffic. Unfortunately, this would prevent the
179 * controller from defining any policy over DNS. Since switches
180 * that are located behind us need to connect to the remote,
181 * in-band cannot simply add a rule that allows DNS traffic from
182 * the local port. The "correct" way to support this is to parse
183 * DNS requests to allow all traffic related to a request for the
184 * remote's name through. Due to the potential security
185 * problems and amount of processing, we decided to hold off for
188 * - Differing Remotes for Switches. All switches must know
189 * the L3 addresses for all the remotes that other switches
190 * may use, since rules need to be set up to allow traffic related
191 * to those remotes through. See rules (f), (g), (h), and (i).
193 * - Differing Routes for Switches. In order for the switch to
194 * allow other switches to connect to a remote through a
195 * gateway, it allows the gateway's traffic through with rules (d)
196 * and (e). If the routes to the remote differ for the two
197 * switches, we will not know the MAC address of the alternate
201 /* Priorities used in classifier for in-band rules. These values are higher
202 * than any that may be set with OpenFlow, and "18" kind of looks like "IB".
203 * The ordering of priorities is not important because all of the rules set up
204 * by in-band control have the same action. The only reason to use more than
205 * one priority is to make the kind of flow easier to see during debugging. */
207 /* One set per bridge. */
208 IBR_FROM_LOCAL_DHCP = 180000, /* (a) From local port, DHCP. */
209 IBR_TO_LOCAL_ARP, /* (b) To local port, ARP. */
210 IBR_FROM_LOCAL_ARP, /* (c) From local port, ARP. */
212 /* One set per unique next-hop MAC. */
213 IBR_TO_NEXT_HOP_ARP, /* (d) To remote MAC, ARP. */
214 IBR_FROM_NEXT_HOP_ARP, /* (e) From remote MAC, ARP. */
216 /* One set per unique remote IP address. */
217 IBR_TO_REMOTE_ARP, /* (f) To remote IP, ARP. */
218 IBR_FROM_REMOTE_ARP, /* (g) From remote IP, ARP. */
220 /* One set per unique remote (IP,port) pair. */
221 IBR_TO_REMOTE_TCP, /* (h) To remote IP, TCP port. */
222 IBR_FROM_REMOTE_TCP /* (i) From remote IP, TCP port. */
225 struct in_band_rule {
228 unsigned int priority;
231 /* Track one remote IP and next hop information. */
232 struct in_band_remote {
233 struct sockaddr_in remote_addr; /* IP address, in network byte order. */
234 uint8_t remote_mac[ETH_ADDR_LEN]; /* Next-hop MAC, all-zeros if unknown. */
235 uint8_t last_remote_mac[ETH_ADDR_LEN]; /* Previous nonzero next-hop MAC. */
236 struct netdev *remote_netdev; /* Device to send to next-hop MAC. */
240 struct ofproto *ofproto;
241 struct status_category *ss_cat;
243 /* Remote information. */
244 time_t next_remote_refresh; /* Refresh timer. */
245 struct in_band_remote *remotes;
248 /* Local information. */
249 time_t next_local_refresh; /* Refresh timer. */
250 uint8_t local_mac[ETH_ADDR_LEN]; /* Current MAC. */
251 struct netdev *local_netdev; /* Local port's network device. */
253 /* Local and remote addresses that are installed as flows. */
254 uint8_t installed_local_mac[ETH_ADDR_LEN];
255 struct sockaddr_in *remote_addrs;
256 size_t n_remote_addrs;
257 uint8_t *remote_macs;
258 size_t n_remote_macs;
261 static struct vlog_rate_limit rl = VLOG_RATE_LIMIT_INIT(60, 60);
264 refresh_remote(struct in_band *ib, struct in_band_remote *r)
266 struct in_addr next_hop_inaddr;
270 /* Find the next-hop IP address. */
271 memset(r->remote_mac, 0, sizeof r->remote_mac);
272 retval = netdev_get_next_hop(ib->local_netdev, &r->remote_addr.sin_addr,
273 &next_hop_inaddr, &next_hop_dev);
275 VLOG_WARN("cannot find route for controller ("IP_FMT"): %s",
276 IP_ARGS(&r->remote_addr.sin_addr), strerror(retval));
279 if (!next_hop_inaddr.s_addr) {
280 next_hop_inaddr = r->remote_addr.sin_addr;
283 /* Open the next-hop network device. */
284 if (!r->remote_netdev
285 || strcmp(netdev_get_name(r->remote_netdev), next_hop_dev))
287 netdev_close(r->remote_netdev);
289 retval = netdev_open_default(next_hop_dev, &r->remote_netdev);
291 VLOG_WARN_RL(&rl, "cannot open netdev %s (next hop "
292 "to controller "IP_FMT"): %s",
293 next_hop_dev, IP_ARGS(&r->remote_addr.sin_addr),
301 /* Look up the MAC address of the next-hop IP address. */
302 retval = netdev_arp_lookup(r->remote_netdev, next_hop_inaddr.s_addr,
305 VLOG_DBG_RL(&rl, "cannot look up remote MAC address ("IP_FMT"): %s",
306 IP_ARGS(&next_hop_inaddr.s_addr), strerror(retval));
309 /* If we don't have a MAC address, then refresh quickly, since we probably
310 * will get a MAC address soon (via ARP). Otherwise, we can afford to wait
312 return eth_addr_is_zero(r->remote_mac) ? 1 : 10;
316 refresh_remotes(struct in_band *ib)
318 struct in_band_remote *r;
321 if (time_now() < ib->next_remote_refresh) {
326 ib->next_remote_refresh = TIME_MAX;
327 for (r = ib->remotes; r < &ib->remotes[ib->n_remotes]; r++) {
328 uint8_t old_remote_mac[ETH_ADDR_LEN];
332 memcpy(old_remote_mac, r->remote_mac, ETH_ADDR_LEN);
334 /* Refresh remote information. */
335 next_refresh = refresh_remote(ib, r) + time_now();
336 ib->next_remote_refresh = MIN(ib->next_remote_refresh, next_refresh);
338 /* If the MAC changed, log the changes. */
339 if (!eth_addr_equals(r->remote_mac, old_remote_mac)) {
341 if (!eth_addr_is_zero(r->remote_mac)
342 && !eth_addr_equals(r->last_remote_mac, r->remote_mac)) {
343 VLOG_DBG("remote MAC address changed from "ETH_ADDR_FMT
345 ETH_ADDR_ARGS(r->last_remote_mac),
346 ETH_ADDR_ARGS(r->remote_mac));
347 memcpy(r->last_remote_mac, r->remote_mac, ETH_ADDR_LEN);
355 /* Refreshes the MAC address of the local port into ib->local_mac, if it is due
356 * for a refresh. Returns true if anything changed, otherwise false. */
358 refresh_local(struct in_band *ib)
360 uint8_t ea[ETH_ADDR_LEN];
364 if (now < ib->next_local_refresh) {
367 ib->next_local_refresh = now + 1;
369 if (netdev_get_etheraddr(ib->local_netdev, ea)
370 || eth_addr_equals(ea, ib->local_mac)) {
374 memcpy(ib->local_mac, ea, ETH_ADDR_LEN);
379 in_band_status_cb(struct status_reply *sr, void *in_band_)
381 struct in_band *in_band = in_band_;
383 if (!eth_addr_is_zero(in_band->local_mac)) {
384 status_reply_put(sr, "local-mac="ETH_ADDR_FMT,
385 ETH_ADDR_ARGS(in_band->local_mac));
388 if (in_band->n_remotes
389 && !eth_addr_is_zero(in_band->remotes[0].remote_mac)) {
390 status_reply_put(sr, "remote-mac="ETH_ADDR_FMT,
391 ETH_ADDR_ARGS(in_band->remotes[0].remote_mac));
395 /* Returns true if 'packet' should be sent to the local port regardless
396 * of the flow table. */
398 in_band_msg_in_hook(struct in_band *in_band, const flow_t *flow,
399 const struct ofpbuf *packet)
405 /* Regardless of how the flow table is configured, we want to be
406 * able to see replies to our DHCP requests. */
407 if (flow->dl_type == htons(ETH_TYPE_IP)
408 && flow->nw_proto == IP_TYPE_UDP
409 && flow->tp_src == htons(DHCP_SERVER_PORT)
410 && flow->tp_dst == htons(DHCP_CLIENT_PORT)
412 struct dhcp_header *dhcp;
414 dhcp = ofpbuf_at(packet, (char *)packet->l7 - (char *)packet->data,
420 refresh_local(in_band);
421 if (!eth_addr_is_zero(in_band->local_mac)
422 && eth_addr_equals(dhcp->chaddr, in_band->local_mac)) {
430 /* Returns true if the rule that would match 'flow' with 'actions' is
431 * allowed to be set up in the datapath. */
433 in_band_rule_check(struct in_band *in_band, const flow_t *flow,
434 const struct odp_actions *actions)
440 /* Don't allow flows that would prevent DHCP replies from being seen
441 * by the local port. */
442 if (flow->dl_type == htons(ETH_TYPE_IP)
443 && flow->nw_proto == IP_TYPE_UDP
444 && flow->tp_src == htons(DHCP_SERVER_PORT)
445 && flow->tp_dst == htons(DHCP_CLIENT_PORT)) {
448 for (i=0; i<actions->n_actions; i++) {
449 if (actions->actions[i].output.type == ODPAT_OUTPUT
450 && actions->actions[i].output.port == ODPP_LOCAL) {
461 init_rule(struct in_band_rule *rule, unsigned int priority)
463 rule->wildcards = OVSFW_ALL;
464 rule->priority = priority;
466 /* Not strictly necessary but seems cleaner. */
467 memset(&rule->flow, 0, sizeof rule->flow);
471 set_in_port(struct in_band_rule *rule, uint16_t odp_port)
473 rule->wildcards &= ~OFPFW_IN_PORT;
474 rule->flow.in_port = odp_port;
478 set_dl_type(struct in_band_rule *rule, uint16_t dl_type)
480 rule->wildcards &= ~OFPFW_DL_TYPE;
481 rule->flow.dl_type = dl_type;
485 set_dl_src(struct in_band_rule *rule, const uint8_t dl_src[ETH_ADDR_LEN])
487 rule->wildcards &= ~OFPFW_DL_SRC;
488 memcpy(rule->flow.dl_src, dl_src, ETH_ADDR_LEN);
492 set_dl_dst(struct in_band_rule *rule, const uint8_t dl_dst[ETH_ADDR_LEN])
494 rule->wildcards &= ~OFPFW_DL_DST;
495 memcpy(rule->flow.dl_dst, dl_dst, ETH_ADDR_LEN);
499 set_tp_src(struct in_band_rule *rule, uint16_t tp_src)
501 rule->wildcards &= ~OFPFW_TP_SRC;
502 rule->flow.tp_src = tp_src;
506 set_tp_dst(struct in_band_rule *rule, uint16_t tp_dst)
508 rule->wildcards &= ~OFPFW_TP_DST;
509 rule->flow.tp_dst = tp_dst;
513 set_nw_proto(struct in_band_rule *rule, uint8_t nw_proto)
515 rule->wildcards &= ~OFPFW_NW_PROTO;
516 rule->flow.nw_proto = nw_proto;
520 set_nw_src(struct in_band_rule *rule, const struct in_addr nw_src)
522 rule->wildcards &= ~OFPFW_NW_SRC_MASK;
523 rule->flow.nw_src = nw_src.s_addr;
527 set_nw_dst(struct in_band_rule *rule, const struct in_addr nw_dst)
529 rule->wildcards &= ~OFPFW_NW_DST_MASK;
530 rule->flow.nw_dst = nw_dst.s_addr;
534 make_rules(struct in_band *ib,
535 void (*cb)(struct in_band *, const struct in_band_rule *))
537 struct in_band_rule rule;
540 if (!eth_addr_is_zero(ib->installed_local_mac)) {
541 /* (a) Allow DHCP requests sent from the local port. */
542 init_rule(&rule, IBR_FROM_LOCAL_DHCP);
543 set_in_port(&rule, ODPP_LOCAL);
544 set_dl_type(&rule, htons(ETH_TYPE_IP));
545 set_dl_src(&rule, ib->installed_local_mac);
546 set_nw_proto(&rule, IP_TYPE_UDP);
547 set_tp_src(&rule, htons(DHCP_CLIENT_PORT));
548 set_tp_dst(&rule, htons(DHCP_SERVER_PORT));
551 /* (b) Allow ARP replies to the local port's MAC address. */
552 init_rule(&rule, IBR_TO_LOCAL_ARP);
553 set_dl_type(&rule, htons(ETH_TYPE_ARP));
554 set_dl_dst(&rule, ib->installed_local_mac);
555 set_nw_proto(&rule, ARP_OP_REPLY);
558 /* (c) Allow ARP requests from the local port's MAC address. */
559 init_rule(&rule, IBR_FROM_LOCAL_ARP);
560 set_dl_type(&rule, htons(ETH_TYPE_ARP));
561 set_dl_src(&rule, ib->installed_local_mac);
562 set_nw_proto(&rule, ARP_OP_REQUEST);
566 for (i = 0; i < ib->n_remote_macs; i++) {
567 const uint8_t *remote_mac = &ib->remote_macs[i * ETH_ADDR_LEN];
570 const uint8_t *prev_mac = &ib->remote_macs[(i - 1) * ETH_ADDR_LEN];
571 if (eth_addr_equals(remote_mac, prev_mac)) {
572 /* Skip duplicates. */
577 /* (d) Allow ARP replies to the next hop's MAC address. */
578 init_rule(&rule, IBR_TO_NEXT_HOP_ARP);
579 set_dl_type(&rule, htons(ETH_TYPE_ARP));
580 set_dl_dst(&rule, remote_mac);
581 set_nw_proto(&rule, ARP_OP_REPLY);
584 /* (e) Allow ARP requests from the next hop's MAC address. */
585 init_rule(&rule, IBR_FROM_NEXT_HOP_ARP);
586 set_dl_type(&rule, htons(ETH_TYPE_ARP));
587 set_dl_src(&rule, remote_mac);
588 set_nw_proto(&rule, ARP_OP_REQUEST);
592 for (i = 0; i < ib->n_remote_addrs; i++) {
593 const struct sockaddr_in *a = &ib->remote_addrs[i];
595 if (!i || a->sin_addr.s_addr != a[-1].sin_addr.s_addr) {
596 /* (f) Allow ARP replies containing the remote's IP address as a
598 init_rule(&rule, IBR_TO_REMOTE_ARP);
599 set_dl_type(&rule, htons(ETH_TYPE_ARP));
600 set_nw_proto(&rule, ARP_OP_REPLY);
601 set_nw_dst(&rule, a->sin_addr);
604 /* (g) Allow ARP requests containing the remote's IP address as a
606 init_rule(&rule, IBR_FROM_REMOTE_ARP);
607 set_dl_type(&rule, htons(ETH_TYPE_ARP));
608 set_nw_proto(&rule, ARP_OP_REQUEST);
609 set_nw_src(&rule, a->sin_addr);
614 || a->sin_addr.s_addr != a[-1].sin_addr.s_addr
615 || a->sin_port != a[-1].sin_port) {
616 /* (h) Allow TCP traffic to the remote's IP and port. */
617 init_rule(&rule, IBR_TO_REMOTE_TCP);
618 set_dl_type(&rule, htons(ETH_TYPE_IP));
619 set_nw_proto(&rule, IP_TYPE_TCP);
620 set_nw_dst(&rule, a->sin_addr);
621 set_tp_dst(&rule, a->sin_port);
624 /* (i) Allow TCP traffic from the remote's IP and port. */
625 init_rule(&rule, IBR_FROM_REMOTE_TCP);
626 set_dl_type(&rule, htons(ETH_TYPE_IP));
627 set_nw_proto(&rule, IP_TYPE_TCP);
628 set_nw_src(&rule, a->sin_addr);
629 set_tp_src(&rule, a->sin_port);
636 drop_rule(struct in_band *ib, const struct in_band_rule *rule)
638 ofproto_delete_flow(ib->ofproto, &rule->flow,
639 rule->wildcards, rule->priority);
642 /* Drops from the flow table all of the flows set up by 'ib', then clears out
643 * the information about the installed flows so that they can be filled in
644 * again if necessary. */
646 drop_rules(struct in_band *ib)
649 make_rules(ib, drop_rule);
651 /* Clear out state. */
652 memset(ib->installed_local_mac, 0, sizeof ib->installed_local_mac);
654 free(ib->remote_addrs);
655 ib->remote_addrs = NULL;
656 ib->n_remote_addrs = 0;
658 free(ib->remote_macs);
659 ib->remote_macs = NULL;
660 ib->n_remote_macs = 0;
664 add_rule(struct in_band *ib, const struct in_band_rule *rule)
666 union ofp_action action;
668 action.type = htons(OFPAT_OUTPUT);
669 action.output.len = htons(sizeof action);
670 action.output.port = htons(OFPP_NORMAL);
671 action.output.max_len = htons(0);
672 ofproto_add_flow(ib->ofproto, &rule->flow, rule->wildcards,
673 rule->priority, &action, 1, 0);
676 /* Inserts flows into the flow table for the current state of 'ib'. */
678 add_rules(struct in_band *ib)
680 make_rules(ib, add_rule);
684 compare_addrs(const void *a_, const void *b_)
686 const struct sockaddr_in *a = a_;
687 const struct sockaddr_in *b = b_;
690 cmp = memcmp(&a->sin_addr.s_addr,
692 sizeof a->sin_addr.s_addr);
696 return memcmp(&a->sin_port, &b->sin_port, sizeof a->sin_port);
700 compare_macs(const void *a, const void *b)
702 return memcmp(a, b, ETH_ADDR_LEN);
706 in_band_run(struct in_band *ib)
708 struct in_band_remote *r;
709 bool local_change, remote_change;
711 local_change = refresh_local(ib);
712 remote_change = refresh_remotes(ib);
713 if (!local_change && !remote_change) {
714 /* Nothing changed, nothing to do. */
718 /* Drop old rules. */
721 /* Figure out new rules. */
722 memcpy(ib->installed_local_mac, ib->local_mac, ETH_ADDR_LEN);
723 ib->remote_addrs = xmalloc(ib->n_remotes * sizeof *ib->remote_addrs);
724 ib->n_remote_addrs = 0;
725 ib->remote_macs = xmalloc(ib->n_remotes * ETH_ADDR_LEN);
726 ib->n_remote_macs = 0;
727 for (r = ib->remotes; r < &ib->remotes[ib->n_remotes]; r++) {
728 ib->remote_addrs[ib->n_remote_addrs++] = r->remote_addr;
729 if (!eth_addr_is_zero(r->remote_mac)) {
730 memcpy(&ib->remote_macs[ib->n_remote_macs * ETH_ADDR_LEN],
731 r->remote_mac, ETH_ADDR_LEN);
736 /* Sort, to allow make_rules() to easily skip duplicates. */
737 qsort(ib->remote_addrs, ib->n_remote_addrs, sizeof *ib->remote_addrs,
739 qsort(ib->remote_macs, ib->n_remote_macs, ETH_ADDR_LEN, compare_macs);
746 in_band_wait(struct in_band *in_band)
748 time_t now = time_now();
750 = MIN(in_band->next_remote_refresh, in_band->next_local_refresh);
752 poll_timer_wait((wakeup - now) * 1000);
754 poll_immediate_wake();
758 /* ofproto has flushed all flows from the flow table and it is calling us back
759 * to allow us to reinstall the ones that are important to us. */
761 in_band_flushed(struct in_band *in_band)
767 in_band_create(struct ofproto *ofproto, struct dpif *dpif,
768 struct switch_status *ss, struct in_band **in_bandp)
770 struct in_band *in_band;
771 char local_name[IF_NAMESIZE];
772 struct netdev *local_netdev;
775 error = dpif_port_get_name(dpif, ODPP_LOCAL,
776 local_name, sizeof local_name);
778 VLOG_ERR("failed to initialize in-band control: cannot get name "
779 "of datapath local port (%s)", strerror(error));
783 error = netdev_open_default(local_name, &local_netdev);
785 VLOG_ERR("failed to initialize in-band control: cannot open "
786 "datapath local port %s (%s)", local_name, strerror(error));
790 in_band = xzalloc(sizeof *in_band);
791 in_band->ofproto = ofproto;
792 in_band->ss_cat = switch_status_register(ss, "in-band",
793 in_band_status_cb, in_band);
794 in_band->next_remote_refresh = TIME_MIN;
795 in_band->next_local_refresh = TIME_MIN;
796 in_band->local_netdev = local_netdev;
804 in_band_destroy(struct in_band *ib)
808 in_band_set_remotes(ib, NULL, 0);
809 switch_status_unregister(ib->ss_cat);
810 netdev_close(ib->local_netdev);
816 any_addresses_changed(struct in_band *ib,
817 const struct sockaddr_in *addresses, size_t n)
821 if (n != ib->n_remotes) {
825 for (i = 0; i < n; i++) {
826 const struct sockaddr_in *old = &ib->remotes[i].remote_addr;
827 const struct sockaddr_in *new = &addresses[i];
829 if (old->sin_addr.s_addr != new->sin_addr.s_addr ||
830 old->sin_port != new->sin_port) {
839 in_band_set_remotes(struct in_band *ib,
840 const struct sockaddr_in *addresses, size_t n)
844 if (!any_addresses_changed(ib, addresses, n)) {
848 /* Clear old remotes. */
849 for (i = 0; i < ib->n_remotes; i++) {
850 netdev_close(ib->remotes[i].remote_netdev);
854 /* Set up new remotes. */
855 ib->remotes = n ? xzalloc(n * sizeof *ib->remotes) : NULL;
857 for (i = 0; i < n; i++) {
858 ib->remotes[i].remote_addr = addresses[i];
861 /* Force refresh in next call to in_band_run(). */
862 ib->next_remote_refresh = TIME_MIN;