replace the kernel's implicit network routes if the metric is set

diff --git a/interface-ip.c b/interface-ip.c
index b681b81..0558b6c 100644 (file)
--- a/interface-ip.c
+++ b/interface-ip.c
@@ -50,23 +50,33 @@ const struct config_param_list route_attr_list = {
        .params = route_attr,
 };
 
-static bool
-match_if_addr(union if_addr *a1, union if_addr *a2, int mask)
+static void
+clear_if_addr(union if_addr *a, int mask)
 {
-       uint8_t *p1, *p2;
        int m_bytes = (mask + 7) / 8;
        uint8_t m_clear = (1 << (m_bytes * 8 - mask)) - 1;
+       uint8_t *p = (uint8_t *) a;
+
+       if (m_bytes < sizeof(a))
+               memset(p + m_bytes, 0, sizeof(a) - m_bytes);
+
+       p[m_bytes - 1] &= ~m_clear;
+}
 
-       p1 = alloca(m_bytes);
-       p2 = alloca(m_bytes);
+static bool
+match_if_addr(union if_addr *a1, union if_addr *a2, int mask)
+{
+       union if_addr *p1, *p2;
 
-       memcpy(p1, a1, m_bytes);
-       memcpy(p2, a2, m_bytes);
+       p1 = alloca(sizeof(*a1));
+       p2 = alloca(sizeof(*a2));
 
-       p1[m_bytes - 1] &= ~m_clear;
-       p2[m_bytes - 1] &= ~m_clear;
+       memcpy(p1, a1, sizeof(*a1));
+       clear_if_addr(p1, mask);
+       memcpy(p2, a2, sizeof(*a2));
+       clear_if_addr(p2, mask);
 
-       return !memcmp(p1, p2, m_bytes);
+       return !memcmp(p1, p2, sizeof(*p1));
 }
 
 static bool
@@ -252,6 +262,7 @@ interface_update_proto_addr(struct vlist_tree *tree,
        struct device *dev;
        struct device_addr *a_new = NULL, *a_old = NULL;
        bool keep = false;
+       struct device_route *route;
 
        ip = container_of(tree, struct interface_ip_settings, addr);
        iface = ip->iface;
@@ -292,10 +303,28 @@ interface_update_proto_addr(struct vlist_tree *tree,
        }
 
        if (node_new) {
-               if (!(a_new->flags & DEVADDR_EXTERNAL) && !keep)
-                       system_add_address(dev, a_new);
                a_new->enabled = true;
+               if (!(a_new->flags & DEVADDR_EXTERNAL) && !keep) {
+                       system_add_address(dev, a_new);
+                       if (iface->metric)
+                               goto replace_route;
+               }
        }
+       return;
+
+replace_route:
+       route = calloc(1, sizeof(*route));
+       route->iface = iface;
+       route->flags = a_new->flags | DEVADDR_KERNEL;
+       route->mask = a_new->mask;
+       memcpy(&route->addr, &a_new->addr, sizeof(route->addr));
+       clear_if_addr(&route->addr, route->mask);
+
+       system_del_route(dev, route);
+
+       route->flags &= ~DEVADDR_KERNEL;
+       route->metric = iface->metric;
+       vlist_add(&ip->route, &route->node, &route->flags);
 }
 
 static bool

diff --git a/interface-ip.h b/interface-ip.h
index ae5a63e..d206eca 100644 (file)
--- a/interface-ip.h
+++ b/interface-ip.h
@@ -26,7 +26,10 @@ enum device_addr_flags {
        DEVADDR_EXTERNAL        = (1 << 2),
 
        /* route overrides the default interface metric */
-       DEVROUTE_METRIC         = (1 << 3)
+       DEVROUTE_METRIC         = (1 << 3),
+
+       /* route automatically added by kernel */
+       DEVADDR_KERNEL          = (1 << 4),
 };
 
 union if_addr {

diff --git a/system-linux.c b/system-linux.c
index af252ea..c7b8b8f 100644 (file)
--- a/system-linux.c
+++ b/system-linux.c
@@ -899,7 +899,7 @@ static int system_rt(struct device *dev, struct device_route *route, int cmd)
                .rtm_family = (alen == 4) ? AF_INET : AF_INET6,
                .rtm_dst_len = route->mask,
                .rtm_table = RT_TABLE_MAIN,
-               .rtm_protocol = RTPROT_BOOT,
+               .rtm_protocol = (route->flags & DEVADDR_KERNEL) ? RTPROT_KERNEL : RTPROT_BOOT,
                .rtm_scope = scope,
                .rtm_type = (cmd == RTM_DELROUTE) ? 0: RTN_UNICAST,
        };