X-Git-Url: https://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=elogind.git;a=blobdiff_plain;f=src%2Fnetwork%2Fnetworkd-link.c;h=660efedc61b0d0dd515b1ab1cae219e735cde7d8;hp=9296a594dbaa60e6cadbf64ee390c7129011b0b1;hb=fecc80c1ba2eed9dadb9a10c15508c356bcc5fc1;hpb=1873a3d344042e818d2a5762c0ebfc3823c8f84d

diff --git a/src/network/networkd-link.c b/src/network/networkd-link.c
index 9296a594d..660efedc6 100644
--- a/src/network/networkd-link.c
+++ b/src/network/networkd-link.c
@@ -21,6 +21,7 @@
 
 #include <netinet/ether.h>
 #include <linux/if.h>
+#include <unistd.h>
 
 #include "networkd.h"
 #include "libudev-private.h"
@@ -29,6 +30,7 @@
 #include "virt.h"
 #include "bus-util.h"
 #include "network-internal.h"
+#include "conf-parser.h"
 
 #include "network-util.h"
 #include "dhcp-lease-internal.h"
@@ -77,7 +79,7 @@ static int link_new(Manager *manager, sd_rtnl_message *message, Link **ret) {
 
         r = sd_rtnl_message_read_ether_addr(message, IFLA_ADDRESS, &link->mac);
         if (r < 0)
-                return r;
+                log_debug_link(link, "MAC address not found for new device, continuing without");
 
         r = asprintf(&link->state_file, "/run/systemd/netif/links/%"PRIu64,
                      link->ifindex);
@@ -105,8 +107,6 @@ static void link_free(Link *link) {
         if (!link)
                 return;
 
-        assert(link->manager);
-
         while ((address = link->addresses)) {
                 LIST_REMOVE(addresses, link->addresses, address);
                 address_free(address);
@@ -127,7 +127,8 @@ static void link_free(Link *link) {
         sd_dhcp6_client_unref(link->dhcp6_client);
         sd_icmp6_nd_unref(link->icmp6_router_discovery);
 
-        hashmap_remove(link->manager->links, &link->ifindex);
+        if (link->manager)
+                hashmap_remove(link->manager->links, &link->ifindex);
 
         free(link->ifname);
 
@@ -205,7 +206,7 @@ static int link_stop_clients(Link *link) {
         if (!link->network)
                 return 0;
 
-        if (link->network->dhcp) {
+        if (IN_SET(link->network->dhcp, DHCP_SUPPORT_BOTH, DHCP_SUPPORT_V6)) {
                 assert(link->dhcp_client);
 
                 k = sd_dhcp_client_stop(link->dhcp_client);
@@ -235,7 +236,7 @@ static int link_stop_clients(Link *link) {
                 }
         }
 
-        if (link->network->dhcp6) {
+        if (IN_SET(link->network->dhcp, DHCP_SUPPORT_BOTH, DHCP_SUPPORT_V6)) {
                 assert(link->icmp6_router_discovery);
 
                 if (link->dhcp6_client) {
@@ -307,7 +308,8 @@ static int link_enter_configured(Link *link) {
         assert(link->network);
         assert(link->state == LINK_STATE_SETTING_ROUTES);
 
-        if (link->network->dhcp_server) {
+        if (link->network->dhcp_server &&
+            !sd_dhcp_server_is_running(link->dhcp_server)) {
                 struct in_addr pool_start;
                 Address *address;
 
@@ -364,7 +366,7 @@ static int link_enter_configured(Link *link) {
 }
 
 static int route_handler(sd_rtnl *rtnl, sd_rtnl_message *m, void *userdata) {
-        Link *link = userdata;
+        _cleanup_link_unref_ Link *link = userdata;
         int r;
 
         assert(link->route_messages > 0);
@@ -374,10 +376,8 @@ static int route_handler(sd_rtnl *rtnl, sd_rtnl_message *m, void *userdata) {
 
         link->route_messages --;
 
-        if (IN_SET(LINK_STATE_FAILED, LINK_STATE_LINGER)) {
-                link_unref(link);
+        if (IN_SET(LINK_STATE_FAILED, LINK_STATE_LINGER))
                 return 1;
-        }
 
         r = sd_rtnl_message_get_errno(m);
         if (r < 0 && r != -EEXIST)
@@ -395,11 +395,54 @@ static int route_handler(sd_rtnl *rtnl, sd_rtnl_message *m, void *userdata) {
                 link_enter_configured(link);
         }
 
-        link_unref(link);
-
         return 1;
 }
 
+static int link_set_dhcp_routes(Link *link) {
+        struct sd_dhcp_route *static_routes;
+        size_t static_routes_size;
+        int r;
+        unsigned i;
+
+        assert(link);
+
+        r = sd_dhcp_lease_get_routes(link->dhcp_lease, &static_routes, &static_routes_size);
+        if (r < 0) {
+                if (r != -ENOENT)
+                        log_warning_link(link, "DHCP error: could not get routes: %s", strerror(-r));
+                return r;
+        }
+
+        for (i = 0; i < static_routes_size; i++) {
+                _cleanup_route_free_ Route *route = NULL;
+
+                r = route_new_dynamic(&route);
+                if (r < 0) {
+                        log_error_link(link, "Could not allocate route: %s",
+                                       strerror(-r));
+                        return r;
+                }
+
+                route->family = AF_INET;
+                route->in_addr.in = static_routes[i].gw_addr;
+                route->dst_addr.in = static_routes[i].dst_addr;
+                route->dst_prefixlen = static_routes[i].dst_prefixlen;
+                route->metrics = DHCP_STATIC_ROUTE_METRIC;
+
+                r = route_configure(route, link, &route_handler);
+                if (r < 0) {
+                        log_warning_link(link,
+                                         "could not set host route: %s", strerror(-r));
+                        return r;
+                }
+
+                link_ref(link);
+                link->route_messages ++;
+        }
+
+        return 0;
+}
+
 static int link_enter_set_routes(Link *link) {
         Route *rt;
         int r;
@@ -472,7 +515,8 @@ static int link_enter_set_routes(Link *link) {
 
                 r = sd_dhcp_lease_get_router(link->dhcp_lease, &gateway);
                 if (r < 0 && r != -ENOENT) {
-                        log_warning_link(link, "DHCP error: %s", strerror(-r));
+                        log_warning_link(link, "DHCP error: could not get gateway: %s",
+                                         strerror(-r));
                         return r;
                 }
 
@@ -498,6 +542,7 @@ static int link_enter_set_routes(Link *link) {
                         route_gw->dst_addr.in = gateway;
                         route_gw->dst_prefixlen = 32;
                         route_gw->scope = RT_SCOPE_LINK;
+                        route_gw->metrics = DHCP_STATIC_ROUTE_METRIC;
 
                         r = route_configure(route_gw, link, &route_handler);
                         if (r < 0) {
@@ -511,6 +556,7 @@ static int link_enter_set_routes(Link *link) {
 
                         route->family = AF_INET;
                         route->in_addr.in = gateway;
+                        route->metrics = DHCP_STATIC_ROUTE_METRIC;
 
                         r = route_configure(route, link, &route_handler);
                         if (r < 0) {
@@ -523,6 +569,9 @@ static int link_enter_set_routes(Link *link) {
                         link_ref(link);
                         link->route_messages ++;
                 }
+
+                if (link->network->dhcp_routes)
+                        link_set_dhcp_routes(link);
         }
 
         if (link->route_messages == 0) {
@@ -533,17 +582,15 @@ static int link_enter_set_routes(Link *link) {
 }
 
 static int route_drop_handler(sd_rtnl *rtnl, sd_rtnl_message *m, void *userdata) {
-        Link *link = userdata;
+        _cleanup_link_unref_ Link *link = userdata;
         int r;
 
         assert(m);
         assert(link);
         assert(link->ifname);
 
-        if (IN_SET(link->state, LINK_STATE_FAILED, LINK_STATE_LINGER)) {
-                link_unref(link);
+        if (IN_SET(link->state, LINK_STATE_FAILED, LINK_STATE_LINGER))
                 return 1;
-        }
 
         r = sd_rtnl_message_get_errno(m);
         if (r < 0 && r != -ESRCH)
@@ -554,13 +601,11 @@ static int route_drop_handler(sd_rtnl *rtnl, sd_rtnl_message *m, void *userdata)
                                 "ERRNO=%d", -r,
                                 NULL);
 
-        link_unref(link);
-
         return 0;
 }
 
 static int address_handler(sd_rtnl *rtnl, sd_rtnl_message *m, void *userdata) {
-        Link *link = userdata;
+        _cleanup_link_unref_ Link *link = userdata;
         int r;
 
         assert(m);
@@ -572,10 +617,8 @@ static int address_handler(sd_rtnl *rtnl, sd_rtnl_message *m, void *userdata) {
 
         link->addr_messages --;
 
-        if (IN_SET(link->state, LINK_STATE_FAILED, LINK_STATE_LINGER)) {
-                link_unref(link);
+        if (IN_SET(link->state, LINK_STATE_FAILED, LINK_STATE_LINGER))
                 return 1;
-        }
 
         r = sd_rtnl_message_get_errno(m);
         if (r < 0 && r != -EEXIST)
@@ -591,14 +634,13 @@ static int address_handler(sd_rtnl *rtnl, sd_rtnl_message *m, void *userdata) {
                 link_enter_set_routes(link);
         }
 
-        link_unref(link);
-
         return 1;
 }
 
 static int link_enter_set_addresses(Link *link) {
         Address *ad;
         int r;
+        uint32_t lifetime = CACHE_INFO_INFINITY_LIFE_TIME;
 
         assert(link);
         assert(link->network);
@@ -675,6 +717,16 @@ static int link_enter_set_addresses(Link *link) {
                         return r;
                 }
 
+                if (!link->network->dhcp_critical) {
+                        r = sd_dhcp_lease_get_lifetime(link->dhcp_lease,
+                                                       &lifetime);
+                        if (r < 0) {
+                                log_warning_link(link, "DHCP error: no lifetime: %s",
+                                                 strerror(-r));
+                                return r;
+                        }
+                }
+
                 r = sd_dhcp_lease_get_netmask(link->dhcp_lease, &netmask);
                 if (r < 0) {
                         log_warning_link(link, "DHCP error: no netmask: %s",
@@ -693,10 +745,14 @@ static int link_enter_set_addresses(Link *link) {
 
                 address->family = AF_INET;
                 address->in_addr.in = addr;
+                address->cinfo.ifa_prefered = lifetime;
+                address->cinfo.ifa_valid = lifetime;
                 address->prefixlen = prefixlen;
                 address->broadcast.s_addr = addr.s_addr | ~netmask.s_addr;
 
-                r = address_configure(address, link, &address_handler);
+                /* use update rather than configure so that we will update the lifetime
+                   of an existing address if it has already been configured */
+                r = address_update(address, link, &address_handler);
                 if (r < 0) {
                         log_warning_link(link,
                                          "could not set addresses: %s", strerror(-r));
@@ -712,17 +768,15 @@ static int link_enter_set_addresses(Link *link) {
 }
 
 static int address_update_handler(sd_rtnl *rtnl, sd_rtnl_message *m, void *userdata) {
-        Link *link = userdata;
+        _cleanup_link_unref_ Link *link = userdata;
         int r;
 
         assert(m);
         assert(link);
         assert(link->ifname);
 
-        if (IN_SET(link->state, LINK_STATE_FAILED, LINK_STATE_LINGER)) {
-                link_unref(link);
+        if (IN_SET(link->state, LINK_STATE_FAILED, LINK_STATE_LINGER))
                 return 1;
-        }
 
         r = sd_rtnl_message_get_errno(m);
         if (r < 0 && r != -ENOENT)
@@ -733,23 +787,19 @@ static int address_update_handler(sd_rtnl *rtnl, sd_rtnl_message *m, void *userd
                                 "ERRNO=%d", -r,
                                 NULL);
 
-        link_unref(link);
-
         return 0;
 }
 
 static int address_drop_handler(sd_rtnl *rtnl, sd_rtnl_message *m, void *userdata) {
-        Link *link = userdata;
+        _cleanup_link_unref_ Link *link = userdata;
         int r;
 
         assert(m);
         assert(link);
         assert(link->ifname);
 
-        if (IN_SET(link->state, LINK_STATE_FAILED, LINK_STATE_LINGER)) {
-                link_unref(link);
+        if (IN_SET(link->state, LINK_STATE_FAILED, LINK_STATE_LINGER))
                 return 1;
-        }
 
         r = sd_rtnl_message_get_errno(m);
         if (r < 0 && r != -EADDRNOTAVAIL)
@@ -760,28 +810,22 @@ static int address_drop_handler(sd_rtnl *rtnl, sd_rtnl_message *m, void *userdat
                                 "ERRNO=%d", -r,
                                 NULL);
 
-        link_unref(link);
-
         return 0;
 }
 
 static int set_hostname_handler(sd_bus *bus, sd_bus_message *m, void *userdata, sd_bus_error *ret_error) {
-        Link *link = userdata;
+        _cleanup_link_unref_ Link *link = userdata;
         int r;
 
         assert(link);
 
-        if (IN_SET(link->state, LINK_STATE_FAILED, LINK_STATE_LINGER)) {
-                link_unref(link);
+        if (IN_SET(link->state, LINK_STATE_FAILED, LINK_STATE_LINGER))
                 return 1;
-        }
 
         r = sd_bus_message_get_errno(m);
         if (r < 0)
                 log_warning_link(link, "Could not set hostname: %s", strerror(-r));
 
-        link_unref(link);
-
         return 1;
 }
 
@@ -815,26 +859,26 @@ static int link_set_hostname(Link *link, const char *hostname) {
                 return r;
 
         r = sd_bus_call_async(link->manager->bus, NULL, m, set_hostname_handler, link, 0);
-        if (r < 0)
+        if (r < 0) {
                 log_error_link(link, "Could not set transient hostname: %s", strerror(-r));
+                return r;
+        }
 
         link_ref(link);
 
-        return r;
+        return 0;
 }
 
 static int set_mtu_handler(sd_rtnl *rtnl, sd_rtnl_message *m, void *userdata) {
-        Link *link = userdata;
+        _cleanup_link_unref_ Link *link = userdata;
         int r;
 
         assert(m);
         assert(link);
         assert(link->ifname);
 
-        if (IN_SET(link->state, LINK_STATE_FAILED, LINK_STATE_LINGER)) {
-                link_unref(link);
+        if (IN_SET(link->state, LINK_STATE_FAILED, LINK_STATE_LINGER))
                 return 1;
-        }
 
         r = sd_rtnl_message_get_errno(m);
         if (r < 0)
@@ -844,8 +888,6 @@ static int set_mtu_handler(sd_rtnl *rtnl, sd_rtnl_message *m, void *userdata) {
                                 "ERRNO=%d", -r,
                                 NULL);
 
-        link_unref(link);
-
         return 1;
 }
 
@@ -886,12 +928,11 @@ static int link_set_mtu(Link *link, uint32_t mtu) {
 
 static int dhcp_lease_lost(Link *link) {
         _cleanup_address_free_ Address *address = NULL;
-        _cleanup_route_free_ Route *route_gw = NULL;
-        _cleanup_route_free_ Route *route = NULL;
         struct in_addr addr;
         struct in_addr netmask;
         struct in_addr gateway;
         unsigned prefixlen;
+        unsigned i;
         int r;
 
         assert(link);
@@ -899,10 +940,36 @@ static int dhcp_lease_lost(Link *link) {
 
         log_warning_link(link, "DHCP lease lost");
 
+        if (link->network->dhcp_routes) {
+                struct sd_dhcp_route *routes;
+                size_t routes_size;
+
+                r = sd_dhcp_lease_get_routes(link->dhcp_lease, &routes, &routes_size);
+                if (r >= 0) {
+                        for (i = 0; i < routes_size; i++) {
+                                _cleanup_route_free_ Route *route = NULL;
+
+                                r = route_new_dynamic(&route);
+                                if (r >= 0) {
+                                        route->family = AF_INET;
+                                        route->in_addr.in = routes[i].gw_addr;
+                                        route->dst_addr.in = routes[i].dst_addr;
+                                        route->dst_prefixlen = routes[i].dst_prefixlen;
+
+                                        route_drop(route, link, &route_drop_handler);
+                                        link_ref(link);
+                                }
+                        }
+                }
+        }
+
         r = address_new_dynamic(&address);
         if (r >= 0) {
                 r = sd_dhcp_lease_get_router(link->dhcp_lease, &gateway);
                 if (r >= 0) {
+                        _cleanup_route_free_ Route *route_gw = NULL;
+                        _cleanup_route_free_ Route *route = NULL;
+
                         r = route_new_dynamic(&route_gw);
                         if (r >= 0) {
                                 route_gw->family = AF_INET;
@@ -966,6 +1033,25 @@ static int dhcp_lease_lost(Link *link) {
         return 0;
 }
 
+static int dhcp_lease_renew(sd_dhcp_client *client, Link *link) {
+        sd_dhcp_lease *lease;
+        int r;
+
+        r = sd_dhcp_client_get_lease(client, &lease);
+        if (r < 0) {
+                log_warning_link(link, "DHCP error: no lease %s",
+                                 strerror(-r));
+                return r;
+        }
+
+        sd_dhcp_lease_unref(link->dhcp_lease);
+        link->dhcp_lease = lease;
+
+        link_enter_set_addresses(link);
+
+        return 0;
+}
+
 static int dhcp_lease_acquired(sd_dhcp_client *client, Link *link) {
         sd_dhcp_lease *lease;
         struct in_addr address;
@@ -1002,7 +1088,8 @@ static int dhcp_lease_acquired(sd_dhcp_client *client, Link *link) {
 
         r = sd_dhcp_lease_get_router(lease, &gateway);
         if (r < 0 && r != -ENOENT) {
-                log_warning_link(link, "DHCP error: %s", strerror(-r));
+                log_warning_link(link, "DHCP error: could not get gateway: %s",
+                                 strerror(-r));
                 return r;
         }
 
@@ -1116,6 +1203,13 @@ static void dhcp_handler(sd_dhcp_client *client, int event, void *userdata) {
                                 }
                         }
 
+                        break;
+                case DHCP_EVENT_RENEW:
+                        r = dhcp_lease_renew(client, link);
+                        if (r < 0) {
+                                link_enter_failed(link);
+                                return;
+                        }
                         break;
                 case DHCP_EVENT_IP_ACQUIRE:
                         r = dhcp_lease_acquired(client, link);
@@ -1136,7 +1230,7 @@ static void dhcp_handler(sd_dhcp_client *client, int event, void *userdata) {
                         break;
                 default:
                         if (event < 0)
-                                log_warning_link(link, "DHCP error: %s", strerror(-event));
+                                log_warning_link(link, "DHCP error: client failed: %s", strerror(-event));
                         else
                                 log_warning_link(link, "DHCP unknown event: %d", event);
                         break;
@@ -1416,7 +1510,7 @@ static int link_acquire_conf(Link *link) {
                 }
         }
 
-        if (link->network->dhcp) {
+        if (IN_SET(link->network->dhcp, DHCP_SUPPORT_BOTH, DHCP_SUPPORT_V4)) {
                 assert(link->dhcp_client);
 
                 log_debug_link(link, "acquiring DHCPv4 lease");
@@ -1429,7 +1523,7 @@ static int link_acquire_conf(Link *link) {
                 }
         }
 
-        if (link->network->dhcp6) {
+        if (IN_SET(link->network->dhcp, DHCP_SUPPORT_BOTH, DHCP_SUPPORT_V6)) {
                 assert(link->icmp6_router_discovery);
 
                 log_debug_link(link, "discovering IPv6 routers");
@@ -1565,15 +1659,13 @@ static int link_update_flags(Link *link, sd_rtnl_message *m) {
 }
 
 static int link_up_handler(sd_rtnl *rtnl, sd_rtnl_message *m, void *userdata) {
-        Link *link = userdata;
+        _cleanup_link_unref_ Link *link = userdata;
         int r;
 
         assert(link);
 
-        if (IN_SET(link->state, LINK_STATE_FAILED, LINK_STATE_LINGER)) {
-                link_unref(link);
+        if (IN_SET(link->state, LINK_STATE_FAILED, LINK_STATE_LINGER))
                 return 1;
-        }
 
         r = sd_rtnl_message_get_errno(m);
         if (r < 0) {
@@ -1587,8 +1679,6 @@ static int link_up_handler(sd_rtnl *rtnl, sd_rtnl_message *m, void *userdata) {
                                 NULL);
         }
 
-        link_unref(link);
-
         return 1;
 }
 
@@ -1634,6 +1724,8 @@ static int link_enslaved(Link *link) {
         assert(link->state == LINK_STATE_ENSLAVING);
         assert(link->network);
 
+        log_debug_link(link, "enslaved");
+
         if (!(link->flags & IFF_UP)) {
                 r = link_up(link);
                 if (r < 0) {
@@ -1642,14 +1734,11 @@ static int link_enslaved(Link *link) {
                 }
         }
 
-        if (!link->network->dhcp && !link->network->ipv4ll)
-                return link_enter_set_addresses(link);
-
-        return 0;
+        return link_enter_set_addresses(link);
 }
 
 static int enslave_handler(sd_rtnl *rtnl, sd_rtnl_message *m, void *userdata) {
-        Link *link = userdata;
+        _cleanup_link_unref_ Link *link = userdata;
         int r;
 
         assert(link);
@@ -1659,13 +1748,11 @@ static int enslave_handler(sd_rtnl *rtnl, sd_rtnl_message *m, void *userdata) {
 
         link->enslaving --;
 
-        if (IN_SET(link->state, LINK_STATE_FAILED, LINK_STATE_LINGER)) {
-                link_unref(link);
+        if (IN_SET(link->state, LINK_STATE_FAILED, LINK_STATE_LINGER))
                 return 1;
-        }
 
         r = sd_rtnl_message_get_errno(m);
-        if (r < 0) {
+        if (r < 0 && r != -EEXIST) {
                 log_struct_link(LOG_ERR, link,
                                 "MESSAGE=%-*s: could not enslave: %s",
                                 IFNAMSIZ,
@@ -1673,17 +1760,12 @@ static int enslave_handler(sd_rtnl *rtnl, sd_rtnl_message *m, void *userdata) {
                                 "ERRNO=%d", -r,
                                 NULL);
                 link_enter_failed(link);
-                link_unref(link);
                 return 1;
         }
 
-        log_debug_link(link, "enslaved");
-
-        if (link->enslaving == 0)
+        if (link->enslaving <= 0)
                 link_enslaved(link);
 
-        link_unref(link);
-
         return 1;
 }
 
@@ -1885,7 +1967,7 @@ static int link_configure(Link *link) {
                         return r;
         }
 
-        if (link->network->dhcp) {
+        if (IN_SET(link->network->dhcp, DHCP_SUPPORT_BOTH, DHCP_SUPPORT_V4)) {
                 r = sd_dhcp_client_new(&link->dhcp_client);
                 if (r < 0)
                         return r;
@@ -1911,6 +1993,27 @@ static int link_configure(Link *link) {
                         if (r < 0)
                                 return r;
                 }
+
+                if (link->network->dhcp_routes) {
+                        r = sd_dhcp_client_set_request_option(link->dhcp_client, DHCP_OPTION_STATIC_ROUTE);
+                        if (r < 0)
+                                return r;
+                        r = sd_dhcp_client_set_request_option(link->dhcp_client, DHCP_OPTION_CLASSLESS_STATIC_ROUTE);
+                        if (r < 0)
+                                return r;
+                }
+
+                if (link->network->dhcp_sendhost) {
+                        _cleanup_free_ char *hostname = gethostname_malloc();
+                        if (!hostname)
+                                return -ENOMEM;
+
+                        if (!is_localhost(hostname)) {
+                                r = sd_dhcp_client_set_hostname(link->dhcp_client, hostname);
+                                if (r < 0)
+                                        return r;
+                        }
+                }
         }
 
         if (link->network->dhcp_server) {
@@ -1923,7 +2026,7 @@ static int link_configure(Link *link) {
                         return r;
         }
 
-        if (link->network->dhcp6) {
+        if (IN_SET(link->network->dhcp, DHCP_SUPPORT_BOTH, DHCP_SUPPORT_V6)) {
                 r = sd_icmp6_nd_new(&link->icmp6_router_discovery);
                 if (r < 0)
                         return r;
@@ -1959,7 +2062,7 @@ static int link_configure(Link *link) {
 }
 
 static int link_initialized_and_synced(sd_rtnl *rtnl, sd_rtnl_message *m, void *userdata) {
-        Link *link = userdata;
+        _cleanup_link_unref_ Link *link = userdata;
         Network *network;
         int r;
 
@@ -1968,14 +2071,14 @@ static int link_initialized_and_synced(sd_rtnl *rtnl, sd_rtnl_message *m, void *
         assert(link->manager);
 
         if (link->state != LINK_STATE_INITIALIZING)
-                return 0;
+                return 1;
 
         log_debug_link(link, "link state is up-to-date");
 
         r = network_get(link->manager, link->udev_device, link->ifname, &link->mac, &network);
         if (r == -ENOENT) {
                 link_enter_unmanaged(link);
-                return 0;
+                return 1;
         } else if (r < 0)
                 return r;
 
@@ -1987,7 +2090,7 @@ static int link_initialized_and_synced(sd_rtnl *rtnl, sd_rtnl_message *m, void *
         if (r < 0)
                 return r;
 
-        return 0;
+        return 1;
 }
 
 int link_initialized(Link *link, struct udev_device *device) {
@@ -2019,6 +2122,8 @@ int link_initialized(Link *link, struct udev_device *device) {
         if (r < 0)
                 return r;
 
+        link_ref(link);
+
         return 0;
 }
 
@@ -2145,12 +2250,13 @@ int link_rtnl_process_address(sd_rtnl *rtnl, sd_rtnl_message *message, void *use
 }
 
 static int link_get_address_handler(sd_rtnl *rtnl, sd_rtnl_message *m, void *userdata) {
-        Link *link = userdata;
+        _cleanup_link_unref_ Link *link = userdata;
         int r;
 
         assert(rtnl);
         assert(m);
         assert(link);
+        assert(link->manager);
 
         for (; m; m = sd_rtnl_message_next(m)) {
                 r = sd_rtnl_message_get_errno(m);
@@ -2195,6 +2301,8 @@ int link_add(Manager *m, sd_rtnl_message *message, Link **ret) {
         if (r < 0)
                 return r;
 
+        link_ref(link);
+
         if (detect_container(NULL) <= 0) {
                 /* not in a container, udev will be around */
                 sprintf(ifindex_str, "n%"PRIu64, link->ifindex);
@@ -2214,6 +2322,9 @@ int link_add(Manager *m, sd_rtnl_message *message, Link **ret) {
                 if (r < 0)
                         return r;
         } else {
+                /* we are calling a callback directly, so must take a ref */
+                link_ref(link);
+
                 r = link_initialized_and_synced(m->rtnl, NULL, link);
                 if (r < 0)
                         return r;
@@ -2456,3 +2567,55 @@ static const char* const link_operstate_table[_LINK_OPERSTATE_MAX] = {
 };
 
 DEFINE_STRING_TABLE_LOOKUP(link_operstate, LinkOperationalState);
+
+static const char* const dhcp_support_table[_DHCP_SUPPORT_MAX] = {
+        [DHCP_SUPPORT_NONE] = "none",
+        [DHCP_SUPPORT_BOTH] = "both",
+        [DHCP_SUPPORT_V4] = "v4",
+        [DHCP_SUPPORT_V6] = "v6",
+};
+
+DEFINE_STRING_TABLE_LOOKUP(dhcp_support, DHCPSupport);
+
+int config_parse_dhcp(
+                const char* unit,
+                const char *filename,
+                unsigned line,
+                const char *section,
+                unsigned section_line,
+                const char *lvalue,
+                int ltype,
+                const char *rvalue,
+                void *data,
+                void *userdata) {
+
+        DHCPSupport *dhcp = data;
+        int k;
+
+        assert(filename);
+        assert(lvalue);
+        assert(rvalue);
+        assert(data);
+
+        /* Our enum shall be a superset of booleans, hence first try
+         * to parse as boolean, and then as enum */
+
+        k = parse_boolean(rvalue);
+        if (k > 0)
+                *dhcp = DHCP_SUPPORT_BOTH;
+        else if (k == 0)
+                *dhcp = DHCP_SUPPORT_NONE;
+        else {
+                DHCPSupport s;
+
+                s = dhcp_support_from_string(rvalue);
+                if (s < 0){
+                        log_syntax(unit, LOG_ERR, filename, line, -s, "Failed to parse DHCP option, ignoring: %s", rvalue);
+                        return 0;
+                }
+
+                *dhcp = s;
+        }
+
+        return 0;
+}