/*
- * Copyright (c) 2009 Nicira Networks.
+ * Copyright (c) 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 "rtnetlink.h"
#include <errno.h>
-#include <sys/socket.h>
-#include <linux/rtnetlink.h>
-#include <net/if.h>
#include <poll.h>
+#include <stdlib.h>
#include "coverage.h"
#include "netlink.h"
+#include "netlink-socket.h"
#include "ofpbuf.h"
-
-#define THIS_MODULE VLM_rtnetlink
#include "vlog.h"
-/* rtnetlink socket. */
-static struct nl_sock *notify_sock;
+VLOG_DEFINE_THIS_MODULE(rtnetlink);
+
+COVERAGE_DEFINE(rtnetlink_changed);
+
+static void rtnetlink_report(struct rtnetlink *rtn, void *change);
+
+struct rtnetlink {
+ struct nl_sock *notify_sock; /* Rtnetlink socket. */
+ struct list all_notifiers; /* All rtnetlink notifiers. */
+
+ /* Passed in by rtnetlink_create(). */
+ int multicast_group; /* Multicast group we listen on. */
+ rtnetlink_parse_func *parse; /* Message parsing function. */
+ void *change; /* Change passed to parse. */
+};
+
+/* Creates an rtnetlink handle which may be used to manage change
+ * notifications. The created handle will listen for rtnetlink messages on
+ * 'multicast_group'. Incoming messages will be parsed with 'parse' which will
+ * be passed 'change' as an argument. */
+struct rtnetlink *
+rtnetlink_create(int multicast_group, rtnetlink_parse_func *parse,
+ void *change)
+{
+ struct rtnetlink *rtn;
-/* All registered notifiers. */
-static struct list all_notifiers = LIST_INITIALIZER(&all_notifiers);
+ rtn = xzalloc(sizeof *rtn);
+ rtn->notify_sock = 0;
+ rtn->multicast_group = multicast_group;
+ rtn->parse = parse;
+ rtn->change = change;
-static void rtnetlink_report_change(const struct nlmsghdr *,
- const struct ifinfomsg *,
- struct nlattr *attrs[]);
-static void rtnetlink_report_notify_error(void);
+ list_init(&rtn->all_notifiers);
+ return rtn;
+}
+
+/* Destroys 'rtn' by freeing any memory it has reserved and closing any sockets
+ * it has opened. */
+void
+rtnetlink_destroy(struct rtnetlink *rtn)
+{
+ if (rtn) {
+ nl_sock_destroy(rtn->notify_sock);
+ free(rtn);
+ }
+}
-/* Registers 'cb' to be called with auxiliary data 'aux' with network device
- * change notifications. The notifier is stored in 'notifier', which the
- * caller must not modify or free.
+/* Registers 'cb' to be called with auxiliary data 'aux' with change
+ * notifications. The notifier is stored in 'notifier', which the caller must
+ * not modify or free.
*
- * This is probably not the function that you want. You should probably be
- * using dpif_port_poll() or netdev_monitor_create(), which unlike this
- * function are not Linux-specific.
+ * This is probably not the function you want. You should probably be using
+ * message specific notifiers like rtnetlink_link_notifier_register().
*
* Returns 0 if successful, otherwise a positive errno value. */
int
-rtnetlink_notifier_register(struct rtnetlink_notifier *notifier,
+rtnetlink_notifier_register(struct rtnetlink *rtn,
+ struct rtnetlink_notifier *notifier,
rtnetlink_notify_func *cb, void *aux)
{
- if (!notify_sock) {
- int error = nl_sock_create(NETLINK_ROUTE, RTNLGRP_LINK, 0, 0,
- ¬ify_sock);
+ if (!rtn->notify_sock) {
+ struct nl_sock *sock;
+ int error;
+
+ error = nl_sock_create(NETLINK_ROUTE, &sock);
+ if (!error) {
+ error = nl_sock_join_mcgroup(sock, rtn->multicast_group);
+ }
if (error) {
+ nl_sock_destroy(sock);
VLOG_WARN("could not create rtnetlink socket: %s",
strerror(error));
return error;
}
+ rtn->notify_sock = sock;
} else {
/* Catch up on notification work so that the new notifier won't
* receive any stale notifications. */
- rtnetlink_notifier_run();
+ rtnetlink_notifier_run(rtn);
}
- list_push_back(&all_notifiers, ¬ifier->node);
+ list_push_back(&rtn->all_notifiers, ¬ifier->node);
notifier->cb = cb;
notifier->aux = aux;
return 0;
}
/* Cancels notification on 'notifier', which must have previously been
- * registered with lxnetdev_notifier_register(). */
+ * registered with rtnetlink_notifier_register(). */
void
-rtnetlink_notifier_unregister(struct rtnetlink_notifier *notifier)
+rtnetlink_notifier_unregister(struct rtnetlink *rtn,
+ struct rtnetlink_notifier *notifier)
{
list_remove(¬ifier->node);
- if (list_is_empty(&all_notifiers)) {
- nl_sock_destroy(notify_sock);
- notify_sock = NULL;
+ if (list_is_empty(&rtn->all_notifiers)) {
+ nl_sock_destroy(rtn->notify_sock);
+ rtn->notify_sock = NULL;
}
}
/* Calls all of the registered notifiers, passing along any as-yet-unreported
- * netdev change events. */
+ * change events. */
void
-rtnetlink_notifier_run(void)
+rtnetlink_notifier_run(struct rtnetlink *rtn)
{
static struct vlog_rate_limit rl = VLOG_RATE_LIMIT_INIT(1, 5);
- if (!notify_sock) {
+ if (!rtn->notify_sock) {
return;
}
for (;;) {
- /* Policy for RTNLGRP_LINK messages.
- *
- * There are *many* more fields in these messages, but currently we
- * only care about these fields. */
- static const struct nl_policy rtnetlink_policy[] = {
- [IFLA_IFNAME] = { .type = NL_A_STRING, .optional = false },
- [IFLA_MASTER] = { .type = NL_A_U32, .optional = true },
- };
-
- struct nlattr *attrs[ARRAY_SIZE(rtnetlink_policy)];
struct ofpbuf *buf;
int error;
- error = nl_sock_recv(notify_sock, &buf, false);
+ error = nl_sock_recv(rtn->notify_sock, &buf, false);
if (!error) {
- if (nl_policy_parse(buf, NLMSG_HDRLEN + sizeof(struct ifinfomsg),
- rtnetlink_policy,
- attrs, ARRAY_SIZE(rtnetlink_policy))) {
- struct ifinfomsg *ifinfo;
-
- ifinfo = (void *) ((char *) buf->data + NLMSG_HDRLEN);
- rtnetlink_report_change(buf->data, ifinfo, attrs);
+ if (rtn->parse(buf, rtn->change)) {
+ rtnetlink_report(rtn, rtn->change);
} else {
VLOG_WARN_RL(&rl, "received bad rtnl message");
- rtnetlink_report_notify_error();
+ rtnetlink_report(rtn, NULL);
}
ofpbuf_delete(buf);
} else if (error == EAGAIN) {
VLOG_WARN_RL(&rl, "error reading rtnetlink socket: %s",
strerror(error));
}
- rtnetlink_report_notify_error();
+ rtnetlink_report(rtn, NULL);
}
}
}
-/* Causes poll_block() to wake up when network device change notifications are
- * ready. */
+/* Causes poll_block() to wake up when change notifications are ready. */
void
-rtnetlink_notifier_wait(void)
+rtnetlink_notifier_wait(struct rtnetlink *rtn)
{
- if (notify_sock) {
- nl_sock_wait(notify_sock, POLLIN);
+ if (rtn->notify_sock) {
+ nl_sock_wait(rtn->notify_sock, POLLIN);
}
}
static void
-rtnetlink_report_change(const struct nlmsghdr *nlmsg,
- const struct ifinfomsg *ifinfo,
- struct nlattr *attrs[])
+rtnetlink_report(struct rtnetlink *rtn, void *change)
{
struct rtnetlink_notifier *notifier;
- struct rtnetlink_change change;
-
- COVERAGE_INC(rtnetlink_changed);
-
- change.nlmsg_type = nlmsg->nlmsg_type;
- change.ifi_index = ifinfo->ifi_index;
- change.ifname = nl_attr_get_string(attrs[IFLA_IFNAME]);
- change.master_ifindex = (attrs[IFLA_MASTER]
- ? nl_attr_get_u32(attrs[IFLA_MASTER]) : 0);
- LIST_FOR_EACH (notifier, struct rtnetlink_notifier, node,
- &all_notifiers) {
- notifier->cb(&change, notifier->aux);
+ if (change) {
+ COVERAGE_INC(rtnetlink_changed);
}
-}
-
-static void
-rtnetlink_report_notify_error(void)
-{
- struct rtnetlink_notifier *notifier;
- LIST_FOR_EACH (notifier, struct rtnetlink_notifier, node,
- &all_notifiers) {
- notifier->cb(NULL, notifier->aux);
+ LIST_FOR_EACH (notifier, node, &rtn->all_notifiers) {
+ notifier->cb(change, notifier->aux);
}
}
+