/*
- * Copyright (c) 2008, 2009 Nicira Networks.
+ * Copyright (c) 2008, 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.
#include <arpa/inet.h>
#include <errno.h>
#include <inttypes.h>
+#include <sys/socket.h>
#include <net/if.h>
#include <string.h>
#include <stdlib.h>
+#include "classifier.h"
#include "dhcp.h"
#include "dpif.h"
#include "flow.h"
-#include "mac-learning.h"
#include "netdev.h"
+#include "netlink.h"
#include "odp-util.h"
-#include "ofp-print.h"
#include "ofproto.h"
#include "ofpbuf.h"
#include "openflow/openflow.h"
-#include "openvswitch/datapath-protocol.h"
#include "packets.h"
#include "poll-loop.h"
-#include "rconn.h"
-#include "status.h"
#include "timeval.h"
-#include "vconn.h"
-
-#define THIS_MODULE VLM_in_band
#include "vlog.h"
-/* In-band control allows a single network to be used for OpenFlow
- * traffic and other data traffic. Refer to ovs-vswitchd.conf(5) and
- * secchan(8) for a description of configuring in-band control.
+VLOG_DEFINE_THIS_MODULE(in_band);
+
+/* In-band control allows a single network to be used for OpenFlow traffic and
+ * other data traffic. See ovs-vswitchd.conf.db(5) for a description of
+ * configuring in-band control.
*
* This comment is an attempt to describe how in-band control works at a
* wire- and implementation-level. Correctly implementing in-band
* gone through many iterations. Please read through and understand the
* reasoning behind the chosen rules before making modifications.
*
- * In Open vSwitch, in-band control is implemented as "hidden" flows (in
- * that they are not visible through OpenFlow) and at a higher priority
- * than wildcarded flows can be set up by the controller. This is done
- * so that the controller cannot interfere with them and possibly break
- * connectivity with its switches. It is possible to see all flows,
- * including in-band ones, with the ovs-appctl "bridge/dump-flows"
- * command.
+ * In Open vSwitch, in-band control is implemented as "hidden" flows (in that
+ * they are not visible through OpenFlow) and at a higher priority than
+ * wildcarded flows can be set up by through OpenFlow. This is done so that
+ * the OpenFlow controller cannot interfere with them and possibly break
+ * connectivity with its switches. It is possible to see all flows, including
+ * in-band ones, with the ovs-appctl "bridge/dump-flows" command.
+ *
+ * The Open vSwitch implementation of in-band control can hide traffic to
+ * arbitrary "remotes", where each remote is one TCP port on one IP address.
+ * Currently the remotes are automatically configured as the in-band OpenFlow
+ * controllers plus the OVSDB managers, if any. (The latter is a requirement
+ * because OVSDB managers are responsible for configuring OpenFlow controllers,
+ * so if the manager cannot be reached then OpenFlow cannot be reconfigured.)
+ *
+ * The following rules (with the OFPP_NORMAL action) are set up on any bridge
+ * that has any remotes:
+ *
+ * (a) DHCP requests sent from the local port.
+ * (b) ARP replies to the local port's MAC address.
+ * (c) ARP requests from the local port's MAC address.
*
- * The following rules are always enabled with the "normal" action by a
- * switch with in-band control:
+ * In-band also sets up the following rules for each unique next-hop MAC
+ * address for the remotes' IPs (the "next hop" is either the remote
+ * itself, if it is on a local subnet, or the gateway to reach the remote):
*
- * a. DHCP requests sent from the local port.
- * b. ARP replies to the local port's MAC address.
- * c. ARP requests from the local port's MAC address.
- * d. ARP replies to the remote side's MAC address. Note that the
- * remote side is either the controller or the gateway to reach
- * the controller.
- * e. ARP requests from the remote side's MAC address. Note that
- * like (d), the MAC is either for the controller or gateway.
- * f. ARP replies containing the controller's IP address as a target.
- * g. ARP requests containing the controller's IP address as a source.
- * h. OpenFlow (6633/tcp) traffic to the controller's IP.
- * i. OpenFlow (6633/tcp) traffic from the controller's IP.
+ * (d) ARP replies to the next hop's MAC address.
+ * (e) ARP requests from the next hop's MAC address.
+ *
+ * In-band also sets up the following rules for each unique remote IP address:
+ *
+ * (f) ARP replies containing the remote's IP address as a target.
+ * (g) ARP requests containing the remote's IP address as a source.
+ *
+ * In-band also sets up the following rules for each unique remote (IP,port)
+ * pair:
+ *
+ * (h) TCP traffic to the remote's IP and port.
+ * (i) TCP traffic from the remote's IP and port.
*
* The goal of these rules is to be as narrow as possible to allow a
- * switch to join a network and be able to communicate with a
- * controller. As mentioned earlier, these rules have higher priority
- * than the controller's rules, so if they are too broad, they may
+ * switch to join a network and be able to communicate with the
+ * remotes. As mentioned earlier, these rules have higher priority
+ * than the controller's rules, so if they are too broad, they may
* prevent the controller from implementing its policy. As such,
* in-band actively monitors some aspects of flow and packet processing
* so that the rules can be made more precise.
* match entries, so in-band control is able to be very precise about
* the flows it prevents. Flows that miss in the datapath are sent to
* userspace to be processed, so preventing these flows from being
- * cached in the "fast path" does not affect correctness. The only type
- * of flow that is currently prevented is one that would prevent DHCP
- * replies from being seen by the local port. For example, a rule that
- * forwarded all DHCP traffic to the controller would not be allowed,
+ * cached in the "fast path" does not affect correctness. The only type
+ * of flow that is currently prevented is one that would prevent DHCP
+ * replies from being seen by the local port. For example, a rule that
+ * forwarded all DHCP traffic to the controller would not be allowed,
* but one that forwarded to all ports (including the local port) would.
*
* As mentioned earlier, packets that miss in the datapath are sent to
* the userspace for processing. The userspace has its own flow table,
- * the "classifier", so in-band checks whether any special processing
- * is needed before the classifier is consulted. If a packet is a DHCP
- * response to a request from the local port, the packet is forwarded to
- * the local port, regardless of the flow table. Note that this requires
- * L7 processing of DHCP replies to determine whether the 'chaddr' field
+ * the "classifier", so in-band checks whether any special processing
+ * is needed before the classifier is consulted. If a packet is a DHCP
+ * response to a request from the local port, the packet is forwarded to
+ * the local port, regardless of the flow table. Note that this requires
+ * L7 processing of DHCP replies to determine whether the 'chaddr' field
* matches the MAC address of the local port.
*
* It is interesting to note that for an L3-based in-band control
- * mechanism, the majority of rules are devoted to ARP traffic. At first
- * glance, some of these rules appear redundant. However, each serves an
- * important role. First, in order to determine the MAC address of the
- * remote side (controller or gateway) for other ARP rules, we must allow
- * ARP traffic for our local port with rules (b) and (c). If we are
- * between a switch and its connection to the controller, we have to
- * allow the other switch's ARP traffic to through. This is done with
+ * mechanism, the majority of rules are devoted to ARP traffic. At first
+ * glance, some of these rules appear redundant. However, each serves an
+ * important role. First, in order to determine the MAC address of the
+ * remote side (controller or gateway) for other ARP rules, we must allow
+ * ARP traffic for our local port with rules (b) and (c). If we are
+ * between a switch and its connection to the remote, we have to
+ * allow the other switch's ARP traffic to through. This is done with
* rules (d) and (e), since we do not know the addresses of the other
- * switches a priori, but do know the controller's or gateway's. Finally,
- * if the controller is running in a local guest VM that is not reached
- * through the local port, the switch that is connected to the VM must
- * allow ARP traffic based on the controller's IP address, since it will
- * not know the MAC address of the local port that is sending the traffic
- * or the MAC address of the controller in the guest VM.
+ * switches a priori, but do know the remote's or gateway's. Finally,
+ * if the remote is running in a local guest VM that is not reached
+ * through the local port, the switch that is connected to the VM must
+ * allow ARP traffic based on the remote's IP address, since it will
+ * not know the MAC address of the local port that is sending the traffic
+ * or the MAC address of the remote in the guest VM.
*
* With a few notable exceptions below, in-band should work in most
* network setups. The following are considered "supported' in the
- * current implementation:
+ * current implementation:
*
- * - Locally Connected. The switch and controller are on the same
+ * - Locally Connected. The switch and remote are on the same
* subnet. This uses rules (a), (b), (c), (h), and (i).
*
- * - Reached through Gateway. The switch and controller are on
+ * - Reached through Gateway. The switch and remote are on
* different subnets and must go through a gateway. This uses
* rules (a), (b), (c), (h), and (i).
*
- * - Between Switch and Controller. This switch is between another
- * switch and the controller, and we want to allow the other
+ * - Between Switch and Remote. This switch is between another
+ * switch and the remote, and we want to allow the other
* switch's traffic through. This uses rules (d), (e), (h), and
* (i). It uses (b) and (c) indirectly in order to know the MAC
* address for rules (d) and (e). Note that DHCP for the other
- * switch will not work unless the controller explicitly lets this
+ * switch will not work unless an OpenFlow controller explicitly lets this
* switch pass the traffic.
*
* - Between Switch and Gateway. This switch is between another
* switch and the gateway, and we want to allow the other switch's
* traffic through. This uses the same rules and logic as the
- * "Between Switch and Controller" configuration described earlier.
+ * "Between Switch and Remote" configuration described earlier.
*
- * - Controller on Local VM. The controller is a guest VM on the
- * system running in-band control. This uses rules (a), (b), (c),
+ * - Remote on Local VM. The remote is a guest VM on the
+ * system running in-band control. This uses rules (a), (b), (c),
* (h), and (i).
*
- * - Controller on Local VM with Different Networks. The controller
+ * - Remote on Local VM with Different Networks. The remote
* is a guest VM on the system running in-band control, but the
- * local port is not used to connect to the controller. For
+ * local port is not used to connect to the remote. For
* example, an IP address is configured on eth0 of the switch. The
- * controller's VM is connected through eth1 of the switch, but an
+ * remote's VM is connected through eth1 of the switch, but an
* IP address has not been configured for that port on the switch.
- * As such, the switch will use eth0 to connect to the controller,
+ * As such, the switch will use eth0 to connect to the remote,
* and eth1's rules about the local port will not work. In the
- * example, the switch attached to eth0 would use rules (a), (b),
- * (c), (h), and (i) on eth0. The switch attached to eth1 would use
+ * example, the switch attached to eth0 would use rules (a), (b),
+ * (c), (h), and (i) on eth0. The switch attached to eth1 would use
* rules (f), (g), (h), and (i).
*
* The following are explicitly *not* supported by in-band control:
*
- * - Specify Controller by Name. Currently, the controller must be
+ * - Specify Remote by Name. Currently, the remote must be
* identified by IP address. A naive approach would be to permit
* all DNS traffic. Unfortunately, this would prevent the
* controller from defining any policy over DNS. Since switches
- * that are located behind us need to connect to the controller,
+ * that are located behind us need to connect to the remote,
* in-band cannot simply add a rule that allows DNS traffic from
* the local port. The "correct" way to support this is to parse
* DNS requests to allow all traffic related to a request for the
- * controller's name through. Due to the potential security
+ * remote's name through. Due to the potential security
* problems and amount of processing, we decided to hold off for
* the time-being.
*
- * - Multiple Controllers. There is nothing intrinsic in the high-
- * level design that prevents using multiple (known) controllers,
- * however, the current implementation's data structures assume
- * only one.
- *
- * - Differing Controllers for Switches. All switches must know
- * the L3 addresses for all the controllers that other switches
+ * - Differing Remotes for Switches. All switches must know
+ * the L3 addresses for all the remotes that other switches
* may use, since rules need to be set up to allow traffic related
- * to those controllers through. See rules (f), (g), (h), and (i).
+ * to those remotes through. See rules (f), (g), (h), and (i).
*
- * - Differing Routes for Switches. In order for the switch to
- * allow other switches to connect to a controller through a
+ * - Differing Routes for Switches. In order for the switch to
+ * allow other switches to connect to a remote through a
* gateway, it allows the gateway's traffic through with rules (d)
- * and (e). If the routes to the controller differ for the two
- * switches, we will not know the MAC address of the alternate
+ * and (e). If the routes to the remote differ for the two
+ * switches, we will not know the MAC address of the alternate
* gateway.
*/
-#define IB_BASE_PRIORITY 18181800
-
+/* Priorities used in classifier for in-band rules. These values are higher
+ * than any that may be set with OpenFlow, and "18" kind of looks like "IB".
+ * The ordering of priorities is not important because all of the rules set up
+ * by in-band control have the same action. The only reason to use more than
+ * one priority is to make the kind of flow easier to see during debugging. */
enum {
- IBR_FROM_LOCAL_DHCP, /* (a) From local port, DHCP. */
+ /* One set per bridge. */
+ IBR_FROM_LOCAL_DHCP = 180000, /* (a) From local port, DHCP. */
IBR_TO_LOCAL_ARP, /* (b) To local port, ARP. */
IBR_FROM_LOCAL_ARP, /* (c) From local port, ARP. */
- IBR_TO_REMOTE_ARP, /* (d) To remote MAC, ARP. */
- IBR_FROM_REMOTE_ARP, /* (e) From remote MAC, ARP. */
- IBR_TO_CTL_ARP, /* (f) To controller IP, ARP. */
- IBR_FROM_CTL_ARP, /* (g) From controller IP, ARP. */
- IBR_TO_CTL_OFP, /* (h) To controller, OpenFlow port. */
- IBR_FROM_CTL_OFP, /* (i) From controller, OpenFlow port. */
-#if OFP_TCP_PORT != OFP_SSL_PORT
-#error Need to support separate TCP and SSL flows.
-#endif
- N_IB_RULES
+
+ /* One set per unique next-hop MAC. */
+ IBR_TO_NEXT_HOP_ARP, /* (d) To remote MAC, ARP. */
+ IBR_FROM_NEXT_HOP_ARP, /* (e) From remote MAC, ARP. */
+
+ /* One set per unique remote IP address. */
+ IBR_TO_REMOTE_ARP, /* (f) To remote IP, ARP. */
+ IBR_FROM_REMOTE_ARP, /* (g) From remote IP, ARP. */
+
+ /* One set per unique remote (IP,port) pair. */
+ IBR_TO_REMOTE_TCP, /* (h) To remote IP, TCP port. */
+ IBR_FROM_REMOTE_TCP /* (i) From remote IP, TCP port. */
};
-struct ib_rule {
- bool installed;
- flow_t flow;
- uint32_t wildcards;
- unsigned int priority;
+/* Track one remote IP and next hop information. */
+struct in_band_remote {
+ struct sockaddr_in remote_addr; /* IP address, in network byte order. */
+ uint8_t remote_mac[ETH_ADDR_LEN]; /* Next-hop MAC, all-zeros if unknown. */
+ uint8_t last_remote_mac[ETH_ADDR_LEN]; /* Previous nonzero next-hop MAC. */
+ struct netdev *remote_netdev; /* Device to send to next-hop MAC. */
};
struct in_band {
struct ofproto *ofproto;
- struct rconn *controller;
- struct status_category *ss_cat;
-
- /* Keep track of local port's information. */
- uint8_t local_mac[ETH_ADDR_LEN]; /* Current MAC. */
- struct netdev *local_netdev; /* Local port's network device. */
- time_t next_local_refresh;
-
- /* Keep track of controller and next hop's information. */
- uint32_t controller_ip; /* Controller IP, 0 if unknown. */
- uint8_t remote_mac[ETH_ADDR_LEN]; /* Remote MAC. */
- struct netdev *remote_netdev;
- uint8_t last_remote_mac[ETH_ADDR_LEN]; /* Previous remote MAC. */
- time_t next_remote_refresh;
-
- /* Rules that we set up. */
- struct ib_rule rules[N_IB_RULES];
+ int queue_id, prev_queue_id;
+
+ /* Remote information. */
+ time_t next_remote_refresh; /* Refresh timer. */
+ struct in_band_remote *remotes;
+ size_t n_remotes;
+
+ /* Local information. */
+ time_t next_local_refresh; /* Refresh timer. */
+ uint8_t local_mac[ETH_ADDR_LEN]; /* Current MAC. */
+ struct netdev *local_netdev; /* Local port's network device. */
+
+ /* Local and remote addresses that are installed as flows. */
+ uint8_t installed_local_mac[ETH_ADDR_LEN];
+ struct sockaddr_in *remote_addrs;
+ size_t n_remote_addrs;
+ uint8_t *remote_macs;
+ size_t n_remote_macs;
};
static struct vlog_rate_limit rl = VLOG_RATE_LIMIT_INIT(60, 60);
-static const uint8_t *
-get_remote_mac(struct in_band *ib)
+static int
+refresh_remote(struct in_band *ib, struct in_band_remote *r)
{
- int retval;
- bool have_mac;
- struct in_addr c_in4; /* Controller's IP address. */
- struct in_addr r_in4; /* Next hop IP address. */
+ struct in_addr next_hop_inaddr;
char *next_hop_dev;
- time_t now = time_now();
-
- if (now >= ib->next_remote_refresh) {
- /* Find the next-hop IP address. */
- c_in4.s_addr = ib->controller_ip;
- memset(ib->remote_mac, 0, sizeof ib->remote_mac);
- retval = netdev_get_next_hop(ib->local_netdev,
- &c_in4, &r_in4, &next_hop_dev);
- if (retval) {
- VLOG_WARN("cannot find route for controller ("IP_FMT"): %s",
- IP_ARGS(&ib->controller_ip), strerror(retval));
- ib->next_remote_refresh = now + 1;
- return NULL;
- }
- if (!r_in4.s_addr) {
- r_in4.s_addr = c_in4.s_addr;
- }
-
- /* Get the next-hop IP and network device. */
- if (!ib->remote_netdev
- || strcmp(netdev_get_name(ib->remote_netdev), next_hop_dev))
- {
- netdev_close(ib->remote_netdev);
- retval = netdev_open(next_hop_dev, NETDEV_ETH_TYPE_NONE,
- &ib->remote_netdev);
- if (retval) {
- VLOG_WARN_RL(&rl, "cannot open netdev %s (next hop "
- "to controller "IP_FMT"): %s",
- next_hop_dev, IP_ARGS(&ib->controller_ip),
- strerror(retval));
- ib->next_remote_refresh = now + 1;
- return NULL;
- }
- }
-
- /* Look up the MAC address of the next-hop IP address. */
- retval = netdev_arp_lookup(ib->remote_netdev, r_in4.s_addr,
- ib->remote_mac);
- if (retval) {
- VLOG_DBG_RL(&rl, "cannot look up remote MAC address ("IP_FMT"): %s",
- IP_ARGS(&r_in4.s_addr), strerror(retval));
- }
- have_mac = !eth_addr_is_zero(ib->remote_mac);
- free(next_hop_dev);
- if (have_mac
- && !eth_addr_equals(ib->last_remote_mac, ib->remote_mac)) {
- VLOG_DBG("remote MAC address changed from "ETH_ADDR_FMT" to "
- ETH_ADDR_FMT,
- ETH_ADDR_ARGS(ib->last_remote_mac),
- ETH_ADDR_ARGS(ib->remote_mac));
- memcpy(ib->last_remote_mac, ib->remote_mac, ETH_ADDR_LEN);
- }
+ int retval;
- /* Schedule next refresh.
- *
- * If we have an IP address but not a MAC address, then refresh
- * quickly, since we probably will get a MAC address soon (via ARP).
- * Otherwise, we can afford to wait a little while. */
- ib->next_remote_refresh
- = now + (!ib->controller_ip || have_mac ? 10 : 1);
+ /* Find the next-hop IP address. */
+ memset(r->remote_mac, 0, sizeof r->remote_mac);
+ retval = netdev_get_next_hop(ib->local_netdev, &r->remote_addr.sin_addr,
+ &next_hop_inaddr, &next_hop_dev);
+ if (retval) {
+ VLOG_WARN("cannot find route for controller ("IP_FMT"): %s",
+ IP_ARGS(&r->remote_addr.sin_addr), strerror(retval));
+ return 1;
+ }
+ if (!next_hop_inaddr.s_addr) {
+ next_hop_inaddr = r->remote_addr.sin_addr;
}
- return !eth_addr_is_zero(ib->remote_mac) ? ib->remote_mac : NULL;
-}
+ /* Open the next-hop network device. */
+ if (!r->remote_netdev
+ || strcmp(netdev_get_name(r->remote_netdev), next_hop_dev))
+ {
+ netdev_close(r->remote_netdev);
-static const uint8_t *
-get_local_mac(struct in_band *ib)
-{
- time_t now = time_now();
- if (now >= ib->next_local_refresh) {
- uint8_t ea[ETH_ADDR_LEN];
- if (ib->local_netdev && !netdev_get_etheraddr(ib->local_netdev, ea)) {
- memcpy(ib->local_mac, ea, ETH_ADDR_LEN);
+ retval = netdev_open_default(next_hop_dev, &r->remote_netdev);
+ if (retval) {
+ VLOG_WARN_RL(&rl, "cannot open netdev %s (next hop "
+ "to controller "IP_FMT"): %s",
+ next_hop_dev, IP_ARGS(&r->remote_addr.sin_addr),
+ strerror(retval));
+ free(next_hop_dev);
+ return 1;
}
- ib->next_local_refresh = now + 1;
}
- return !eth_addr_is_zero(ib->local_mac) ? ib->local_mac : NULL;
+ free(next_hop_dev);
+
+ /* Look up the MAC address of the next-hop IP address. */
+ retval = netdev_arp_lookup(r->remote_netdev, next_hop_inaddr.s_addr,
+ r->remote_mac);
+ if (retval) {
+ VLOG_DBG_RL(&rl, "cannot look up remote MAC address ("IP_FMT"): %s",
+ IP_ARGS(&next_hop_inaddr.s_addr), strerror(retval));
+ }
+
+ /* If we don't have a MAC address, then refresh quickly, since we probably
+ * will get a MAC address soon (via ARP). Otherwise, we can afford to wait
+ * a little while. */
+ return eth_addr_is_zero(r->remote_mac) ? 1 : 10;
}
-static void
-in_band_status_cb(struct status_reply *sr, void *in_band_)
+static bool
+refresh_remotes(struct in_band *ib)
{
- struct in_band *in_band = in_band_;
+ struct in_band_remote *r;
+ bool any_changes;
- if (!eth_addr_is_zero(in_band->local_mac)) {
- status_reply_put(sr, "local-mac="ETH_ADDR_FMT,
- ETH_ADDR_ARGS(in_band->local_mac));
+ if (time_now() < ib->next_remote_refresh) {
+ return false;
}
- if (!eth_addr_is_zero(in_band->remote_mac)) {
- status_reply_put(sr, "remote-mac="ETH_ADDR_FMT,
- ETH_ADDR_ARGS(in_band->remote_mac));
+ any_changes = false;
+ ib->next_remote_refresh = TIME_MAX;
+ for (r = ib->remotes; r < &ib->remotes[ib->n_remotes]; r++) {
+ uint8_t old_remote_mac[ETH_ADDR_LEN];
+ time_t next_refresh;
+
+ /* Save old MAC. */
+ memcpy(old_remote_mac, r->remote_mac, ETH_ADDR_LEN);
+
+ /* Refresh remote information. */
+ next_refresh = refresh_remote(ib, r) + time_now();
+ ib->next_remote_refresh = MIN(ib->next_remote_refresh, next_refresh);
+
+ /* If the MAC changed, log the changes. */
+ if (!eth_addr_equals(r->remote_mac, old_remote_mac)) {
+ any_changes = true;
+ if (!eth_addr_is_zero(r->remote_mac)
+ && !eth_addr_equals(r->last_remote_mac, r->remote_mac)) {
+ VLOG_DBG("remote MAC address changed from "ETH_ADDR_FMT
+ " to "ETH_ADDR_FMT,
+ ETH_ADDR_ARGS(r->last_remote_mac),
+ ETH_ADDR_ARGS(r->remote_mac));
+ memcpy(r->last_remote_mac, r->remote_mac, ETH_ADDR_LEN);
+ }
+ }
}
-}
-static void
-drop_flow(struct in_band *in_band, int rule_idx)
-{
- struct ib_rule *rule = &in_band->rules[rule_idx];
-
- if (rule->installed) {
- rule->installed = false;
- ofproto_delete_flow(in_band->ofproto, &rule->flow, rule->wildcards,
- rule->priority);
- }
+ return any_changes;
}
-/* out_port and fixed_fields are assumed never to change. */
-static void
-set_up_flow(struct in_band *in_band, int rule_idx, const flow_t *flow,
- uint32_t fixed_fields, uint16_t out_port)
+/* Refreshes the MAC address of the local port into ib->local_mac, if it is due
+ * for a refresh. Returns true if anything changed, otherwise false. */
+static bool
+refresh_local(struct in_band *ib)
{
- struct ib_rule *rule = &in_band->rules[rule_idx];
+ uint8_t ea[ETH_ADDR_LEN];
+ time_t now;
- if (!rule->installed || memcmp(flow, &rule->flow, sizeof *flow)) {
- union ofp_action action;
-
- drop_flow(in_band, rule_idx);
-
- rule->installed = true;
- rule->flow = *flow;
- rule->wildcards = OFPFW_ALL & ~fixed_fields;
- rule->priority = IB_BASE_PRIORITY + (N_IB_RULES - rule_idx);
+ now = time_now();
+ if (now < ib->next_local_refresh) {
+ return false;
+ }
+ ib->next_local_refresh = now + 1;
- action.type = htons(OFPAT_OUTPUT);
- action.output.len = htons(sizeof action);
- action.output.port = htons(out_port);
- action.output.max_len = htons(0);
- ofproto_add_flow(in_band->ofproto, &rule->flow, rule->wildcards,
- rule->priority, &action, 1, 0);
+ if (netdev_get_etheraddr(ib->local_netdev, ea)
+ || eth_addr_equals(ea, ib->local_mac)) {
+ return false;
}
+
+ memcpy(ib->local_mac, ea, ETH_ADDR_LEN);
+ return true;
}
/* Returns true if 'packet' should be sent to the local port regardless
- * of the flow table. */
+ * of the flow table. */
bool
-in_band_msg_in_hook(struct in_band *in_band, const flow_t *flow,
+in_band_msg_in_hook(struct in_band *in_band, const struct flow *flow,
const struct ofpbuf *packet)
{
- if (!in_band) {
- return false;
- }
-
/* Regardless of how the flow table is configured, we want to be
* able to see replies to our DHCP requests. */
if (flow->dl_type == htons(ETH_TYPE_IP)
- && flow->nw_proto == IP_TYPE_UDP
+ && flow->nw_proto == IPPROTO_UDP
&& flow->tp_src == htons(DHCP_SERVER_PORT)
&& flow->tp_dst == htons(DHCP_CLIENT_PORT)
&& packet->l7) {
struct dhcp_header *dhcp;
- const uint8_t *local_mac;
dhcp = ofpbuf_at(packet, (char *)packet->l7 - (char *)packet->data,
sizeof *dhcp);
return false;
}
- local_mac = get_local_mac(in_band);
- if (eth_addr_equals(dhcp->chaddr, local_mac)) {
+ refresh_local(in_band);
+ if (!eth_addr_is_zero(in_band->local_mac)
+ && eth_addr_equals(dhcp->chaddr, in_band->local_mac)) {
return true;
}
}
return false;
}
-/* Returns true if the rule that would match 'flow' with 'actions' is
+/* Returns true if the rule that would match 'flow' with 'actions' is
* allowed to be set up in the datapath. */
bool
-in_band_rule_check(struct in_band *in_band, const flow_t *flow,
- const struct odp_actions *actions)
+in_band_rule_check(const struct flow *flow,
+ const struct nlattr *actions, size_t actions_len)
{
- if (!in_band) {
- return true;
- }
-
/* Don't allow flows that would prevent DHCP replies from being seen
* by the local port. */
if (flow->dl_type == htons(ETH_TYPE_IP)
- && flow->nw_proto == IP_TYPE_UDP
- && flow->tp_src == htons(DHCP_SERVER_PORT)
+ && flow->nw_proto == IPPROTO_UDP
+ && flow->tp_src == htons(DHCP_SERVER_PORT)
&& flow->tp_dst == htons(DHCP_CLIENT_PORT)) {
- int i;
+ const struct nlattr *a;
+ unsigned int left;
- for (i=0; i<actions->n_actions; i++) {
- if (actions->actions[i].output.type == ODPAT_OUTPUT
- && actions->actions[i].output.port == ODPP_LOCAL) {
+ NL_ATTR_FOR_EACH_UNSAFE (a, left, actions, actions_len) {
+ if (nl_attr_type(a) == ODP_ACTION_ATTR_OUTPUT
+ && nl_attr_get_u32(a) == ODPP_LOCAL) {
return true;
- }
+ }
}
return false;
}
return true;
}
-void
-in_band_run(struct in_band *in_band)
+static void
+make_rules(struct in_band *ib,
+ void (*cb)(struct in_band *, const struct cls_rule *))
{
- time_t now = time_now();
- uint32_t controller_ip;
- const uint8_t *remote_mac;
- const uint8_t *local_mac;
- flow_t flow;
-
- if (now < in_band->next_remote_refresh
- && now < in_band->next_local_refresh) {
- return;
+ struct cls_rule rule;
+ size_t i;
+
+ if (!eth_addr_is_zero(ib->installed_local_mac)) {
+ /* (a) Allow DHCP requests sent from the local port. */
+ cls_rule_init_catchall(&rule, IBR_FROM_LOCAL_DHCP);
+ cls_rule_set_in_port(&rule, ODPP_LOCAL);
+ cls_rule_set_dl_type(&rule, htons(ETH_TYPE_IP));
+ cls_rule_set_dl_src(&rule, ib->installed_local_mac);
+ cls_rule_set_nw_proto(&rule, IPPROTO_UDP);
+ cls_rule_set_tp_src(&rule, htons(DHCP_CLIENT_PORT));
+ cls_rule_set_tp_dst(&rule, htons(DHCP_SERVER_PORT));
+ cb(ib, &rule);
+
+ /* (b) Allow ARP replies to the local port's MAC address. */
+ cls_rule_init_catchall(&rule, IBR_TO_LOCAL_ARP);
+ cls_rule_set_dl_type(&rule, htons(ETH_TYPE_ARP));
+ cls_rule_set_dl_dst(&rule, ib->installed_local_mac);
+ cls_rule_set_nw_proto(&rule, ARP_OP_REPLY);
+ cb(ib, &rule);
+
+ /* (c) Allow ARP requests from the local port's MAC address. */
+ cls_rule_init_catchall(&rule, IBR_FROM_LOCAL_ARP);
+ cls_rule_set_dl_type(&rule, htons(ETH_TYPE_ARP));
+ cls_rule_set_dl_src(&rule, ib->installed_local_mac);
+ cls_rule_set_nw_proto(&rule, ARP_OP_REQUEST);
+ cb(ib, &rule);
}
- controller_ip = rconn_get_remote_ip(in_band->controller);
- if (in_band->controller_ip && controller_ip != in_band->controller_ip) {
- VLOG_DBG("controller IP address changed from "IP_FMT" to "IP_FMT,
- IP_ARGS(&in_band->controller_ip),
- IP_ARGS(&controller_ip));
+ for (i = 0; i < ib->n_remote_macs; i++) {
+ const uint8_t *remote_mac = &ib->remote_macs[i * ETH_ADDR_LEN];
+
+ if (i > 0) {
+ const uint8_t *prev_mac = &ib->remote_macs[(i - 1) * ETH_ADDR_LEN];
+ if (eth_addr_equals(remote_mac, prev_mac)) {
+ /* Skip duplicates. */
+ continue;
+ }
+ }
+
+ /* (d) Allow ARP replies to the next hop's MAC address. */
+ cls_rule_init_catchall(&rule, IBR_TO_NEXT_HOP_ARP);
+ cls_rule_set_dl_type(&rule, htons(ETH_TYPE_ARP));
+ cls_rule_set_dl_dst(&rule, remote_mac);
+ cls_rule_set_nw_proto(&rule, ARP_OP_REPLY);
+ cb(ib, &rule);
+
+ /* (e) Allow ARP requests from the next hop's MAC address. */
+ cls_rule_init_catchall(&rule, IBR_FROM_NEXT_HOP_ARP);
+ cls_rule_set_dl_type(&rule, htons(ETH_TYPE_ARP));
+ cls_rule_set_dl_src(&rule, remote_mac);
+ cls_rule_set_nw_proto(&rule, ARP_OP_REQUEST);
+ cb(ib, &rule);
}
- in_band->controller_ip = controller_ip;
-
- remote_mac = get_remote_mac(in_band);
- local_mac = get_local_mac(in_band);
-
- if (local_mac) {
- /* Allow DHCP requests to be sent from the local port. */
- memset(&flow, 0, sizeof flow);
- flow.in_port = ODPP_LOCAL;
- flow.dl_type = htons(ETH_TYPE_IP);
- memcpy(flow.dl_src, local_mac, ETH_ADDR_LEN);
- flow.nw_proto = IP_TYPE_UDP;
- flow.tp_src = htons(DHCP_CLIENT_PORT);
- flow.tp_dst = htons(DHCP_SERVER_PORT);
- set_up_flow(in_band, IBR_FROM_LOCAL_DHCP, &flow,
- (OFPFW_IN_PORT | OFPFW_DL_TYPE | OFPFW_DL_SRC
- | OFPFW_NW_PROTO | OFPFW_TP_SRC | OFPFW_TP_DST),
- OFPP_NORMAL);
-
- /* Allow the connection's interface to receive directed ARP traffic. */
- memset(&flow, 0, sizeof flow);
- flow.dl_type = htons(ETH_TYPE_ARP);
- memcpy(flow.dl_dst, local_mac, ETH_ADDR_LEN);
- flow.nw_proto = ARP_OP_REPLY;
- set_up_flow(in_band, IBR_TO_LOCAL_ARP, &flow,
- (OFPFW_DL_TYPE | OFPFW_DL_DST | OFPFW_NW_PROTO),
- OFPP_NORMAL);
-
- /* Allow the connection's interface to be the source of ARP traffic. */
- memset(&flow, 0, sizeof flow);
- flow.dl_type = htons(ETH_TYPE_ARP);
- memcpy(flow.dl_src, local_mac, ETH_ADDR_LEN);
- flow.nw_proto = ARP_OP_REQUEST;
- set_up_flow(in_band, IBR_FROM_LOCAL_ARP, &flow,
- (OFPFW_DL_TYPE | OFPFW_DL_SRC | OFPFW_NW_PROTO),
- OFPP_NORMAL);
- } else {
- drop_flow(in_band, IBR_TO_LOCAL_ARP);
- drop_flow(in_band, IBR_FROM_LOCAL_ARP);
+
+ for (i = 0; i < ib->n_remote_addrs; i++) {
+ const struct sockaddr_in *a = &ib->remote_addrs[i];
+
+ if (!i || a->sin_addr.s_addr != a[-1].sin_addr.s_addr) {
+ /* (f) Allow ARP replies containing the remote's IP address as a
+ * target. */
+ cls_rule_init_catchall(&rule, IBR_TO_REMOTE_ARP);
+ cls_rule_set_dl_type(&rule, htons(ETH_TYPE_ARP));
+ cls_rule_set_nw_proto(&rule, ARP_OP_REPLY);
+ cls_rule_set_nw_dst(&rule, a->sin_addr.s_addr);
+ cb(ib, &rule);
+
+ /* (g) Allow ARP requests containing the remote's IP address as a
+ * source. */
+ cls_rule_init_catchall(&rule, IBR_FROM_REMOTE_ARP);
+ cls_rule_set_dl_type(&rule, htons(ETH_TYPE_ARP));
+ cls_rule_set_nw_proto(&rule, ARP_OP_REQUEST);
+ cls_rule_set_nw_src(&rule, a->sin_addr.s_addr);
+ cb(ib, &rule);
+ }
+
+ if (!i
+ || a->sin_addr.s_addr != a[-1].sin_addr.s_addr
+ || a->sin_port != a[-1].sin_port) {
+ /* (h) Allow TCP traffic to the remote's IP and port. */
+ cls_rule_init_catchall(&rule, IBR_TO_REMOTE_TCP);
+ cls_rule_set_dl_type(&rule, htons(ETH_TYPE_IP));
+ cls_rule_set_nw_proto(&rule, IPPROTO_TCP);
+ cls_rule_set_nw_dst(&rule, a->sin_addr.s_addr);
+ cls_rule_set_tp_dst(&rule, a->sin_port);
+ cb(ib, &rule);
+
+ /* (i) Allow TCP traffic from the remote's IP and port. */
+ cls_rule_init_catchall(&rule, IBR_FROM_REMOTE_TCP);
+ cls_rule_set_dl_type(&rule, htons(ETH_TYPE_IP));
+ cls_rule_set_nw_proto(&rule, IPPROTO_TCP);
+ cls_rule_set_nw_src(&rule, a->sin_addr.s_addr);
+ cls_rule_set_tp_src(&rule, a->sin_port);
+ cb(ib, &rule);
+ }
}
+}
+
+static void
+drop_rule(struct in_band *ib, const struct cls_rule *rule)
+{
+ ofproto_delete_flow(ib->ofproto, rule);
+}
- if (remote_mac) {
- /* Allow ARP replies to the remote side's MAC. */
- memset(&flow, 0, sizeof flow);
- flow.dl_type = htons(ETH_TYPE_ARP);
- memcpy(flow.dl_dst, remote_mac, ETH_ADDR_LEN);
- flow.nw_proto = ARP_OP_REPLY;
- set_up_flow(in_band, IBR_TO_REMOTE_ARP, &flow,
- (OFPFW_DL_TYPE | OFPFW_DL_DST | OFPFW_NW_PROTO),
- OFPP_NORMAL);
-
- /* Allow ARP requests from the remote side's MAC. */
- memset(&flow, 0, sizeof flow);
- flow.dl_type = htons(ETH_TYPE_ARP);
- memcpy(flow.dl_src, remote_mac, ETH_ADDR_LEN);
- flow.nw_proto = ARP_OP_REQUEST;
- set_up_flow(in_band, IBR_FROM_REMOTE_ARP, &flow,
- (OFPFW_DL_TYPE | OFPFW_DL_SRC | OFPFW_NW_PROTO),
- OFPP_NORMAL);
+/* Drops from the flow table all of the flows set up by 'ib', then clears out
+ * the information about the installed flows so that they can be filled in
+ * again if necessary. */
+static void
+drop_rules(struct in_band *ib)
+{
+ /* Drop rules. */
+ make_rules(ib, drop_rule);
+
+ /* Clear out state. */
+ memset(ib->installed_local_mac, 0, sizeof ib->installed_local_mac);
+
+ free(ib->remote_addrs);
+ ib->remote_addrs = NULL;
+ ib->n_remote_addrs = 0;
+
+ free(ib->remote_macs);
+ ib->remote_macs = NULL;
+ ib->n_remote_macs = 0;
+}
+
+static void
+add_rule(struct in_band *ib, const struct cls_rule *rule)
+{
+ struct {
+ struct nx_action_set_queue nxsq;
+ struct ofp_action_output oao;
+ } actions;
+
+ memset(&actions, 0, sizeof actions);
+
+ actions.oao.type = htons(OFPAT_OUTPUT);
+ actions.oao.len = htons(sizeof actions.oao);
+ actions.oao.port = htons(OFPP_NORMAL);
+ actions.oao.max_len = htons(0);
+
+ if (ib->queue_id < 0) {
+ ofproto_add_flow(ib->ofproto, rule,
+ (union ofp_action *) &actions.oao, 1);
} else {
- drop_flow(in_band, IBR_TO_REMOTE_ARP);
- drop_flow(in_band, IBR_FROM_REMOTE_ARP);
+ actions.nxsq.type = htons(OFPAT_VENDOR);
+ actions.nxsq.len = htons(sizeof actions.nxsq);
+ actions.nxsq.vendor = htonl(NX_VENDOR_ID);
+ actions.nxsq.subtype = htons(NXAST_SET_QUEUE);
+ actions.nxsq.queue_id = htonl(ib->queue_id);
+
+ ofproto_add_flow(ib->ofproto, rule, (union ofp_action *) &actions,
+ sizeof actions / sizeof(union ofp_action));
}
+}
- if (controller_ip) {
- /* Allow ARP replies to the controller's IP. */
- memset(&flow, 0, sizeof flow);
- flow.dl_type = htons(ETH_TYPE_ARP);
- flow.nw_proto = ARP_OP_REPLY;
- flow.nw_dst = controller_ip;
- set_up_flow(in_band, IBR_TO_CTL_ARP, &flow,
- (OFPFW_DL_TYPE | OFPFW_NW_PROTO | OFPFW_NW_DST_MASK),
- OFPP_NORMAL);
-
- /* Allow ARP requests from the controller's IP. */
- memset(&flow, 0, sizeof flow);
- flow.dl_type = htons(ETH_TYPE_ARP);
- flow.nw_proto = ARP_OP_REQUEST;
- flow.nw_src = controller_ip;
- set_up_flow(in_band, IBR_FROM_CTL_ARP, &flow,
- (OFPFW_DL_TYPE | OFPFW_NW_PROTO | OFPFW_NW_SRC_MASK),
- OFPP_NORMAL);
-
- /* OpenFlow traffic to or from the controller.
- *
- * (A given field's value is completely ignored if it is wildcarded,
- * which is why we can get away with using a single 'flow' in each
- * case here.) */
- memset(&flow, 0, sizeof flow);
- flow.dl_type = htons(ETH_TYPE_IP);
- flow.nw_proto = IP_TYPE_TCP;
- flow.nw_src = controller_ip;
- flow.nw_dst = controller_ip;
- flow.tp_src = htons(OFP_TCP_PORT);
- flow.tp_dst = htons(OFP_TCP_PORT);
- set_up_flow(in_band, IBR_TO_CTL_OFP, &flow,
- (OFPFW_DL_TYPE | OFPFW_NW_PROTO | OFPFW_NW_DST_MASK
- | OFPFW_TP_DST), OFPP_NORMAL);
- set_up_flow(in_band, IBR_FROM_CTL_OFP, &flow,
- (OFPFW_DL_TYPE | OFPFW_NW_PROTO | OFPFW_NW_SRC_MASK
- | OFPFW_TP_SRC), OFPP_NORMAL);
- } else {
- drop_flow(in_band, IBR_TO_CTL_ARP);
- drop_flow(in_band, IBR_FROM_CTL_ARP);
- drop_flow(in_band, IBR_TO_CTL_OFP);
- drop_flow(in_band, IBR_FROM_CTL_OFP);
+/* Inserts flows into the flow table for the current state of 'ib'. */
+static void
+add_rules(struct in_band *ib)
+{
+ make_rules(ib, add_rule);
+}
+
+static int
+compare_addrs(const void *a_, const void *b_)
+{
+ const struct sockaddr_in *a = a_;
+ const struct sockaddr_in *b = b_;
+ int cmp;
+
+ cmp = memcmp(&a->sin_addr.s_addr,
+ &b->sin_addr.s_addr,
+ sizeof a->sin_addr.s_addr);
+ if (cmp) {
+ return cmp;
}
+ return memcmp(&a->sin_port, &b->sin_port, sizeof a->sin_port);
+}
+
+static int
+compare_macs(const void *a, const void *b)
+{
+ return eth_addr_compare_3way(a, b);
+}
+
+void
+in_band_run(struct in_band *ib)
+{
+ bool local_change, remote_change, queue_id_change;
+ struct in_band_remote *r;
+
+ local_change = refresh_local(ib);
+ remote_change = refresh_remotes(ib);
+ queue_id_change = ib->queue_id != ib->prev_queue_id;
+ if (!local_change && !remote_change && !queue_id_change) {
+ /* Nothing changed, nothing to do. */
+ return;
+ }
+ ib->prev_queue_id = ib->queue_id;
+
+ /* Drop old rules. */
+ drop_rules(ib);
+
+ /* Figure out new rules. */
+ memcpy(ib->installed_local_mac, ib->local_mac, ETH_ADDR_LEN);
+ ib->remote_addrs = xmalloc(ib->n_remotes * sizeof *ib->remote_addrs);
+ ib->n_remote_addrs = 0;
+ ib->remote_macs = xmalloc(ib->n_remotes * ETH_ADDR_LEN);
+ ib->n_remote_macs = 0;
+ for (r = ib->remotes; r < &ib->remotes[ib->n_remotes]; r++) {
+ ib->remote_addrs[ib->n_remote_addrs++] = r->remote_addr;
+ if (!eth_addr_is_zero(r->remote_mac)) {
+ memcpy(&ib->remote_macs[ib->n_remote_macs * ETH_ADDR_LEN],
+ r->remote_mac, ETH_ADDR_LEN);
+ ib->n_remote_macs++;
+ }
+ }
+
+ /* Sort, to allow make_rules() to easily skip duplicates. */
+ qsort(ib->remote_addrs, ib->n_remote_addrs, sizeof *ib->remote_addrs,
+ compare_addrs);
+ qsort(ib->remote_macs, ib->n_remote_macs, ETH_ADDR_LEN, compare_macs);
+
+ /* Add new rules. */
+ add_rules(ib);
}
void
in_band_wait(struct in_band *in_band)
{
- time_t now = time_now();
- time_t wakeup
+ long long int wakeup
= MIN(in_band->next_remote_refresh, in_band->next_local_refresh);
- if (wakeup > now) {
- poll_timer_wait((wakeup - now) * 1000);
- } else {
- poll_immediate_wake();
- }
+ poll_timer_wait_until(wakeup * 1000);
}
+/* ofproto has flushed all flows from the flow table and it is calling us back
+ * to allow us to reinstall the ones that are important to us. */
void
in_band_flushed(struct in_band *in_band)
{
- int i;
-
- for (i = 0; i < N_IB_RULES; i++) {
- in_band->rules[i].installed = false;
- }
+ add_rules(in_band);
}
int
-in_band_create(struct ofproto *ofproto, struct dpif *dpif,
- struct switch_status *ss, struct rconn *controller,
+in_band_create(struct ofproto *ofproto, const char *local_name,
struct in_band **in_bandp)
{
struct in_band *in_band;
- char local_name[IF_NAMESIZE];
struct netdev *local_netdev;
int error;
- error = dpif_port_get_name(dpif, ODPP_LOCAL,
- local_name, sizeof local_name);
- if (error) {
- VLOG_ERR("failed to initialize in-band control: cannot get name "
- "of datapath local port (%s)", strerror(error));
- return error;
- }
-
- error = netdev_open(local_name, NETDEV_ETH_TYPE_NONE, &local_netdev);
+ *in_bandp = NULL;
+ error = netdev_open_default(local_name, &local_netdev);
if (error) {
VLOG_ERR("failed to initialize in-band control: cannot open "
"datapath local port %s (%s)", local_name, strerror(error));
return error;
}
- in_band = xcalloc(1, sizeof *in_band);
+ in_band = xzalloc(sizeof *in_band);
in_band->ofproto = ofproto;
- in_band->controller = controller;
- in_band->ss_cat = switch_status_register(ss, "in-band",
- in_band_status_cb, in_band);
- in_band->local_netdev = local_netdev;
- in_band->next_local_refresh = TIME_MIN;
- in_band->remote_netdev = NULL;
+ in_band->queue_id = in_band->prev_queue_id = -1;
in_band->next_remote_refresh = TIME_MIN;
+ in_band->next_local_refresh = TIME_MIN;
+ in_band->local_netdev = local_netdev;
*in_bandp = in_band;
}
void
-in_band_destroy(struct in_band *in_band)
+in_band_destroy(struct in_band *ib)
+{
+ if (ib) {
+ drop_rules(ib);
+ in_band_set_remotes(ib, NULL, 0);
+ netdev_close(ib->local_netdev);
+ free(ib);
+ }
+}
+
+static bool
+any_addresses_changed(struct in_band *ib,
+ const struct sockaddr_in *addresses, size_t n)
+{
+ size_t i;
+
+ if (n != ib->n_remotes) {
+ return true;
+ }
+
+ for (i = 0; i < n; i++) {
+ const struct sockaddr_in *old = &ib->remotes[i].remote_addr;
+ const struct sockaddr_in *new = &addresses[i];
+
+ if (old->sin_addr.s_addr != new->sin_addr.s_addr ||
+ old->sin_port != new->sin_port) {
+ return true;
+ }
+ }
+
+ return false;
+}
+
+void
+in_band_set_remotes(struct in_band *ib,
+ const struct sockaddr_in *addresses, size_t n)
{
- if (in_band) {
- switch_status_unregister(in_band->ss_cat);
- netdev_close(in_band->local_netdev);
- netdev_close(in_band->remote_netdev);
- /* We don't own the rconn. */
+ size_t i;
+
+ if (!any_addresses_changed(ib, addresses, n)) {
+ return;
}
+
+ /* Clear old remotes. */
+ for (i = 0; i < ib->n_remotes; i++) {
+ netdev_close(ib->remotes[i].remote_netdev);
+ }
+ free(ib->remotes);
+
+ /* Set up new remotes. */
+ ib->remotes = n ? xzalloc(n * sizeof *ib->remotes) : NULL;
+ ib->n_remotes = n;
+ for (i = 0; i < n; i++) {
+ ib->remotes[i].remote_addr = addresses[i];
+ }
+
+ /* Force refresh in next call to in_band_run(). */
+ ib->next_remote_refresh = TIME_MIN;
+}
+
+/* Sets the OpenFlow queue used by flows set up by 'ib' to 'queue_id'. If
+ * 'queue_id' is negative, 'ib' will not set any queue (which is also the
+ * default). */
+void
+in_band_set_queue(struct in_band *ib, int queue_id)
+{
+ ib->queue_id = queue_id;
}