recognize stacked interfaces (e.g. dsa) and handle their dependencies

[project/netifd.git] / system-linux.c

diff --git a/system-linux.c b/system-linux.c
index 57a4617..d26f181 100644 (file)
--- a/system-linux.c
+++ b/system-linux.c
@@ -34,6 +34,7 @@ static int sock_ioctl = -1;
 static struct nl_sock *sock_rtnl = NULL;
 
 static int cb_rtnl_event(struct nl_msg *msg, void *arg);
+static void handle_hotplug_event(struct uloop_fd *u, unsigned int events);
 
 static void
 handler_nl_event(struct uloop_fd *u, unsigned int events)
@@ -43,7 +44,7 @@ handler_nl_event(struct uloop_fd *u, unsigned int events)
 }
 
 static struct nl_sock *
-create_socket(int protocol)
+create_socket(int protocol, int groups)
 {
        struct nl_sock *sock;
 
@@ -51,6 +52,9 @@ create_socket(int protocol)
        if (!sock)
                return NULL;
 
+       if (groups)
+               nl_join_groups(sock, groups);
+
        if (nl_connect(sock, protocol))
                return NULL;
 
@@ -58,15 +62,15 @@ create_socket(int protocol)
 }
 
 static bool
-create_raw_event_socket(struct event_socket *ev, int protocol,
+create_raw_event_socket(struct event_socket *ev, int protocol, int groups,
                        uloop_fd_handler cb)
 {
-       ev->sock = create_socket(protocol);
+       ev->sock = create_socket(protocol, groups);
        if (!ev->sock)
                return false;
 
        ev->uloop.fd = nl_socket_get_fd(ev->sock);
-       ev->uloop.cb = handler_nl_event;
+       ev->uloop.cb = cb;
        uloop_fd_add(&ev->uloop, ULOOP_READ | ULOOP_EDGE_TRIGGER);
        return true;
 }
@@ -82,24 +86,29 @@ create_event_socket(struct event_socket *ev, int protocol,
 
        nl_cb_set(ev->cb, NL_CB_VALID, NL_CB_CUSTOM, cb, NULL);
 
-       return create_raw_event_socket(ev, protocol, handler_nl_event);
+       return create_raw_event_socket(ev, protocol, 0, handler_nl_event);
 }
 
 int system_init(void)
 {
        static struct event_socket rtnl_event;
+       static struct event_socket hotplug_event;
 
        sock_ioctl = socket(AF_LOCAL, SOCK_DGRAM, 0);
        fcntl(sock_ioctl, F_SETFD, fcntl(sock_ioctl, F_GETFD) | FD_CLOEXEC);
 
        // Prepare socket for routing / address control
-       sock_rtnl = create_socket(NETLINK_ROUTE);
+       sock_rtnl = create_socket(NETLINK_ROUTE, 0);
        if (!sock_rtnl)
                return -1;
 
        if (!create_event_socket(&rtnl_event, NETLINK_ROUTE, cb_rtnl_event))
                return -1;
 
+       if (!create_raw_event_socket(&hotplug_event, NETLINK_KOBJECT_UEVENT, 1,
+                                    handle_hotplug_event))
+               return -1;
+
        // Receive network link events form kernel
        nl_socket_add_membership(rtnl_event.sock, RTNLGRP_LINK);
 
@@ -150,12 +159,78 @@ static int cb_rtnl_event(struct nl_msg *msg, void *arg)
                goto out;
 
        dev->ifindex = ifi->ifi_index;
-       device_set_present(dev, (nh->nlmsg_type == RTM_NEWLINK));
+       /* TODO: parse link status */
 
 out:
        return 0;
 }
 
+static void
+handle_hotplug_msg(char *data, int size)
+{
+       const char *subsystem = NULL, *interface = NULL;
+       char *cur, *end, *sep;
+       struct device *dev;
+       int skip;
+       bool add;
+
+       if (!strncmp(data, "add@", 4))
+               add = true;
+       else if (!strncmp(data, "remove@", 7))
+               add = false;
+       else
+               return;
+
+       skip = strlen(data) + 1;
+       end = data + size;
+
+       for (cur = data + skip; cur < end; cur += skip) {
+               skip = strlen(cur) + 1;
+
+               sep = strchr(cur, '=');
+               if (!sep)
+                       continue;
+
+               *sep = 0;
+               if (!strcmp(cur, "INTERFACE"))
+                       interface = sep + 1;
+               else if (!strcmp(cur, "SUBSYSTEM")) {
+                       subsystem = sep + 1;
+                       if (strcmp(subsystem, "net") != 0)
+                               return;
+               }
+               if (subsystem && interface)
+                       goto found;
+       }
+       return;
+
+found:
+       dev = device_get(interface, false);
+       if (!dev)
+               return;
+
+       if (dev->type != &simple_device_type)
+               return;
+
+       device_set_present(dev, add);
+}
+
+static void
+handle_hotplug_event(struct uloop_fd *u, unsigned int events)
+{
+       struct event_socket *ev = container_of(u, struct event_socket, uloop);
+       struct sockaddr_nl nla;
+       unsigned char *buf = NULL;
+       int size;
+
+       while ((size = nl_recv(ev->sock, &nla, &buf, NULL)) > 0) {
+               if (nla.nl_pid == 0)
+                       handle_hotplug_msg((char *) buf, size);
+
+               free(buf);
+       }
+}
+
 static int system_rtnl_call(struct nl_msg *msg)
 {
        int s = -(nl_send_auto_complete(sock_rtnl, msg)
@@ -528,10 +603,41 @@ int system_if_down(struct device *dev)
 
 int system_if_check(struct device *dev)
 {
-       device_set_present(dev, (system_if_resolve(dev) >= 0));
+       device_set_present(dev, (system_if_resolve(dev) > 0));
        return 0;
 }
 
+struct device *
+system_if_get_parent(struct device *dev)
+{
+       char buf[64], *devname;
+       int ifindex, iflink, len;
+       FILE *f;
+
+       snprintf(buf, sizeof(buf), "/sys/class/net/%s/iflink", dev->ifname);
+       f = fopen(buf, "r");
+       if (!f)
+               return NULL;
+
+       len = fread(buf, 1, sizeof(buf) - 1, f);
+       fclose(f);
+
+       if (len <= 0)
+               return NULL;
+
+       buf[len] = 0;
+       iflink = strtoul(buf, NULL, 0);
+       ifindex = system_if_resolve(dev);
+       if (!iflink || iflink == ifindex)
+               return NULL;
+
+       devname = if_indextoname(iflink, buf);
+       if (!devname)
+               return NULL;
+
+       return device_get(devname, true);
+}
+
 int system_if_dump_stats(struct device *dev, struct blob_buf *b)
 {
        const char *const counters[] = {