system-linux: return 0 in system_init

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

diff --git a/system-linux.c b/system-linux.c
index d09fd63..db809bb 100644 (file)
--- a/system-linux.c
+++ b/system-linux.c
@@ -5,12 +5,13 @@
 #include <linux/sockios.h>
 #include <linux/if_vlan.h>
 
-#include <stddef.h>
 #include <string.h>
 #include <fcntl.h>
-#include <errno.h>
 
 #include <netlink/msg.h>
+#include <netlink/attr.h>
+#include <netlink/socket.h>
+#include <libubox/uloop.h>
 
 #include "netifd.h"
 #include "device.h"
@@ -18,26 +19,98 @@
 
 static int sock_ioctl = -1;
 static struct nl_sock *sock_rtnl = NULL;
+static struct nl_sock *sock_rtnl_event = NULL;
+
+static void handler_rtnl_event(struct uloop_fd *u, unsigned int events);
+static int cb_rtnl_event(struct nl_msg *msg, void *arg);
+static struct uloop_fd rtnl_event = {.cb = handler_rtnl_event};
+static struct nl_cb *nl_cb_rtnl_event;
 
 int system_init(void)
 {
        sock_ioctl = socket(AF_LOCAL, SOCK_DGRAM, 0);
        fcntl(sock_ioctl, F_SETFD, fcntl(sock_ioctl, F_GETFD) | FD_CLOEXEC);
 
-       if ((sock_rtnl = nl_socket_alloc())) {
-               if (nl_connect(sock_rtnl, NETLINK_ROUTE)) {
-                       nl_socket_free(sock_rtnl);
-                       sock_rtnl = NULL;
-               }
-       }
+       // Prepare socket for routing / address control
+       sock_rtnl = nl_socket_alloc();
+       if (!sock_rtnl)
+               return -1;
+
+       if (nl_connect(sock_rtnl, NETLINK_ROUTE))
+               goto error_free_sock;
+
+       // Prepare socket for link events
+       nl_cb_rtnl_event = nl_cb_alloc(NL_CB_DEFAULT);
+       if (!nl_cb_rtnl_event)
+               goto error_free_sock;
+
+       nl_cb_set(nl_cb_rtnl_event, NL_CB_VALID, NL_CB_CUSTOM,
+                 cb_rtnl_event, NULL);
+
+       sock_rtnl_event = nl_socket_alloc();
+       if (!sock_rtnl_event)
+               goto error_free_cb;
+
+       if (nl_connect(sock_rtnl_event, NETLINK_ROUTE))
+               goto error_free_event;
+
+       // Receive network link events form kernel
+       nl_socket_add_membership(sock_rtnl_event, RTNLGRP_LINK);
+
+       rtnl_event.fd = nl_socket_get_fd(sock_rtnl_event);
+       uloop_fd_add(&rtnl_event, ULOOP_READ | ULOOP_EDGE_TRIGGER);
+
+       return 0;
+
+error_free_event:
+       nl_socket_free(sock_rtnl_event);
+       sock_rtnl_event = NULL;
+error_free_cb:
+       nl_cb_put(nl_cb_rtnl_event);
+       nl_cb_rtnl_event = NULL;
+error_free_sock:
+       nl_socket_free(sock_rtnl);
+       sock_rtnl = NULL;
+       return -1;
+}
+
+// If socket is ready for reading parse netlink events
+static void handler_rtnl_event(struct uloop_fd *u, unsigned int events)
+{
+       nl_recvmsgs(sock_rtnl_event, nl_cb_rtnl_event);
+}
+
+// Evaluate netlink messages
+static int cb_rtnl_event(struct nl_msg *msg, void *arg)
+{
+       struct nlmsghdr *nh = nlmsg_hdr(msg);
+       struct ifinfomsg *ifi = NLMSG_DATA(nh);
+       struct nlattr *nla[__IFLA_MAX];
+
+       if (nh->nlmsg_type != RTM_DELLINK && nh->nlmsg_type != RTM_NEWLINK)
+               goto out;
+
+       nlmsg_parse(nh, sizeof(*ifi), nla, __IFLA_MAX - 1, NULL);
+       if (!nla[IFLA_IFNAME])
+               goto out;
+
+       struct device *dev = device_get(RTA_DATA(nla[IFLA_IFNAME]), false);
+       if (!dev)
+               goto out;
+
+       dev->ifindex = ifi->ifi_index;
+       device_set_present(dev, (nh->nlmsg_type == RTM_NEWLINK));
 
-       return -(sock_ioctl < 0 || !sock_rtnl);
+out:
+       return 0;
 }
 
 static int system_rtnl_call(struct nl_msg *msg)
 {
-       return -(nl_send_auto_complete(sock_rtnl, msg)
+       int s = -(nl_send_auto_complete(sock_rtnl, msg)
                        || nl_wait_for_ack(sock_rtnl));
+       nlmsg_free(msg);
+       return s;
 }
 
 int system_bridge_addbr(struct device *bridge)
@@ -98,8 +171,19 @@ static int system_if_flags(struct device *dev, unsigned add, unsigned rem)
        return ioctl(sock_ioctl, SIOCSIFFLAGS, &ifr);
 }
 
+static int system_if_resolve(struct device *dev)
+{
+       struct ifreq ifr;
+       strncpy(ifr.ifr_name, dev->ifname, sizeof(ifr.ifr_name));
+       if (!ioctl(sock_ioctl, SIOCGIFINDEX, &ifr))
+               return ifr.ifr_ifindex;
+       else
+               return 0;
+}
+
 int system_if_up(struct device *dev)
 {
+       dev->ifindex = system_if_resolve(dev);
        return system_if_flags(dev, IFF_UP, 0);
 }
 
@@ -110,15 +194,7 @@ int system_if_down(struct device *dev)
 
 int system_if_check(struct device *dev)
 {
-       struct ifreq ifr;
-       strncpy(ifr.ifr_name, dev->ifname, sizeof(ifr.ifr_name));
-       if (ioctl(sock_ioctl, SIOCGIFINDEX, &ifr))
-               return -1;
-
-       dev->ifindex = ifr.ifr_ifindex;
-
-       /* if (!strcmp(dev->ifname, "eth0"))
-               device_set_present(dev, true); */
+       device_set_present(dev, (system_if_resolve(dev) >= 0));
        return 0;
 }
 
@@ -136,7 +212,7 @@ static int system_addr(struct device *dev, struct device_addr *addr, int cmd)
                return -1;
 
        nlmsg_append(msg, &ifa, sizeof(ifa), 0);
-       nla_put(msg, IFA_ADDRESS, alen, &addr->addr);
+       nla_put(msg, IFA_LOCAL, alen, &addr->addr);
        return system_rtnl_call(msg);
 }