netdev: add ability to set IPv4 addresses and add a default gateway.

diff --git a/include/netdev.h b/include/netdev.h
index 33f549a4422d0cba67bd5ea4527469fd81a58bd5..e58a90dd954d624c482b12c07956bd7338d26724 100644 (file)
--- a/include/netdev.h
+++ b/include/netdev.h
@@ -71,6 +71,8 @@ int netdev_get_mtu(const struct netdev *);
 int netdev_get_speed(const struct netdev *);
 uint32_t netdev_get_features(const struct netdev *);
 bool netdev_get_in4(const struct netdev *, struct in_addr *);
+int netdev_set_in4(struct netdev *, struct in_addr addr, struct in_addr mask);
+int netdev_add_router(struct netdev *, struct in_addr router);
 bool netdev_get_in6(const struct netdev *, struct in6_addr *);
 int netdev_get_flags(const struct netdev *, enum netdev_flags *);
 int netdev_set_flags(struct netdev *, enum netdev_flags, bool permanent);

diff --git a/lib/netdev.c b/lib/netdev.c
index b6195940947e0db00c949e6102b203e9fe8f970b..34c7747ddd803ca59a2b08bb5456fd04f01099fd 100644 (file)
--- a/lib/netdev.c
+++ b/lib/netdev.c
@@ -538,6 +538,75 @@ netdev_get_in4(const struct netdev *netdev, struct in_addr *in4)
     return in4->s_addr != INADDR_ANY;
 }
 
+static void
+make_in4_sockaddr(struct sockaddr *sa, struct in_addr addr)
+{
+    struct sockaddr_in sin;
+    memset(&sin, 0, sizeof sin);
+    sin.sin_family = AF_INET;
+    sin.sin_addr = addr;
+    sin.sin_port = 0;
+
+    memset(sa, 0, sizeof *sa);
+    memcpy(sa, &sin, sizeof sin);
+}
+
+static int
+do_set_addr(struct netdev *netdev, int sock,
+            int ioctl_nr, const char *ioctl_name, struct in_addr addr)
+{
+    struct ifreq ifr;
+    int error;
+
+    strncpy(ifr.ifr_name, netdev->name, sizeof ifr.ifr_name);
+    make_in4_sockaddr(&ifr.ifr_addr, addr);
+    error = ioctl(sock, ioctl_nr, &ifr) < 0 ? errno : 0;
+    if (error) {
+        VLOG_WARN("ioctl(%s): %s", ioctl_name, strerror(error));
+    }
+    return error;
+}
+
+/* Assigns 'addr' as 'netdev''s IPv4 address and 'mask' as its netmask.  If
+ * 'addr' is INADDR_ANY, 'netdev''s IPv4 address is cleared.  Returns a
+ * positive errno value. */
+int
+netdev_set_in4(struct netdev *netdev, struct in_addr addr, struct in_addr mask)
+{
+    int error;
+
+    error = do_set_addr(netdev, af_inet_sock,
+                        SIOCSIFADDR, "SIOCSIFADDR", addr);
+    if (!error) {
+        netdev->in4 = addr;
+        if (addr.s_addr != INADDR_ANY) {
+            error = do_set_addr(netdev, af_inet_sock,
+                                SIOCSIFNETMASK, "SIOCSIFNETMASK", mask);
+        }
+    }
+    return error;
+}
+
+/* Adds 'router' as a default gateway for 'netdev''s IP address. */
+int
+netdev_add_router(struct netdev *netdev, struct in_addr router)
+{
+    struct in_addr any = { INADDR_ANY };
+    struct rtentry rt;
+    int error;
+
+    memset(&rt, 0, sizeof rt);
+    make_in4_sockaddr(&rt.rt_dst, any);
+    make_in4_sockaddr(&rt.rt_gateway, router);
+    make_in4_sockaddr(&rt.rt_genmask, any);
+    rt.rt_flags = RTF_UP | RTF_GATEWAY;
+    error = ioctl(af_inet_sock, SIOCADDRT, &rt) < 0 ? errno : 0;
+    if (error) {
+        VLOG_WARN("ioctl(SIOCADDRT): %s", strerror(error));
+    }
+    return error;
+}
+
 /* If 'netdev' has an assigned IPv6 address, sets '*in6' to that address and
  * returns true.  Otherwise, returns false. */
 bool