dhcp: pass IPv6 link-local address to DHCP client

The DHCP client from new libsystemd-network requires a link-local IPv6
address to be passed to the library; add a new argument to
nm_dhcp_manager_start_ip6() and related functions.

src/devices/nm-device.c

@@ -4660,6 +4660,9 @@ dhcp6_start_with_link_ready (NMDevice *self, NMConnection *connection)
 	GByteArray *tmp = NULL;
 	const guint8 *hw_addr;
 	size_t hw_addr_len = 0;
+	const struct in6_addr *ll_addr = NULL;
+	NMIP6Config *ip6_config;
+	int i;
 
 	g_assert (connection);
 	s_ip6 = nm_connection_get_setting_ip6_config (connection);
@@ -4671,10 +4674,22 @@ dhcp6_start_with_link_ready (NMDevice *self, NMConnection *connection)
 		g_byte_array_append (tmp, hw_addr, hw_addr_len);
 	}
 
+	ip6_config = priv->ext_ip6_config;
+	for (i = 0; ip6_config && i < nm_ip6_config_get_num_addresses (ip6_config); i++) {
+		const NMPlatformIP6Address *addr = nm_ip6_config_get_address (ip6_config, i);
+
+		if (IN6_IS_ADDR_LINKLOCAL (&addr->address)) {
+			ll_addr = &addr->address;
+			break;
+		}
+	}
+	g_return_val_if_fail (ll_addr, FALSE);
+
 	priv->dhcp6_client = nm_dhcp_manager_start_ip6 (nm_dhcp_manager_get (),
 	                                                nm_device_get_ip_iface (self),
 	                                                nm_device_get_ip_ifindex (self),
 	                                                tmp,
+	                                                ll_addr,
 	                                                nm_connection_get_uuid (connection),
 	                                                nm_device_get_ip6_route_metric (self),
 	                                                nm_setting_ip_config_get_dhcp_send_hostname (s_ip6),

src/dhcp-manager/nm-dhcp-client.c

@@ -545,6 +545,7 @@ get_duid (NMDhcpClient *self)
 gboolean
 nm_dhcp_client_start_ip6 (NMDhcpClient *self,
                           const char *dhcp_anycast_addr,
+                          const struct in6_addr *ll_addr,
                           const char *hostname,
                           gboolean info_only,
                           NMSettingIP6ConfigPrivacy privacy)
@@ -581,6 +582,7 @@ nm_dhcp_client_start_ip6 (NMDhcpClient *self,
 
 	return NM_DHCP_CLIENT_GET_CLASS (self)->ip6_start (self,
 	                                                   dhcp_anycast_addr,
+	                                                   ll_addr,
 	                                                   info_only,
 	                                                   privacy,
 	                                                   priv->duid);

src/dhcp-manager/nm-dhcp-client.h

@@ -69,6 +69,7 @@ typedef struct {
 
 	gboolean (*ip6_start)     (NMDhcpClient *self,
 	                           const char *anycast_addr,
+	                           const struct in6_addr *ll_addr,
 	                           gboolean info_only,
 	                           NMSettingIP6ConfigPrivacy privacy,
 	                           const GByteArray *duid);
@@ -138,6 +139,7 @@ gboolean nm_dhcp_client_start_ip4 (NMDhcpClient *self,
 
 gboolean nm_dhcp_client_start_ip6 (NMDhcpClient *self,
                                    const char *dhcp_anycast_addr,
+                                   const struct in6_addr *ll_addr,
                                    const char *hostname,
                                    gboolean info_only,
                                    NMSettingIP6ConfigPrivacy privacy);

src/dhcp-manager/nm-dhcp-dhclient.c

@@ -487,6 +487,7 @@ ip4_start (NMDhcpClient *client, const char *dhcp_anycast_addr, const char *last
 static gboolean
 ip6_start (NMDhcpClient *client,
            const char *dhcp_anycast_addr,
+           const struct in6_addr *ll_addr,
            gboolean info_only,
            NMSettingIP6ConfigPrivacy privacy,
            const GByteArray *duid)

src/dhcp-manager/nm-dhcp-dhcpcd.c

@@ -143,6 +143,7 @@ ip4_start (NMDhcpClient *client, const char *dhcp_anycast_addr, const char *last
 static gboolean
 ip6_start (NMDhcpClient *client,
            const char *dhcp_anycast_addr,
+           const struct in6_addr *ll_addr,
            gboolean info_only,
            NMSettingIP6ConfigPrivacy privacy,
            const GByteArray *duid)

src/dhcp-manager/nm-dhcp-manager.c

@@ -216,6 +216,7 @@ client_start (NMDhcpManager *self,
               const char *uuid,
               guint32 priority,
               gboolean ipv6,
+              const struct in6_addr *ipv6_ll_addr,
               const char *dhcp_client_id,
               guint32 timeout,
               const char *dhcp_anycast_addr,
@@ -261,7 +262,7 @@ client_start (NMDhcpManager *self,
 	g_signal_connect (client, NM_DHCP_CLIENT_SIGNAL_STATE_CHANGED, G_CALLBACK (client_state_changed), self);
 
 	if (ipv6)
-		success = nm_dhcp_client_start_ip6 (client, dhcp_anycast_addr, hostname, info_only, privacy);
+		success = nm_dhcp_client_start_ip6 (client, dhcp_anycast_addr, ipv6_ll_addr, hostname, info_only, privacy);
 	else
 		success = nm_dhcp_client_start_ip4 (client, dhcp_client_id, dhcp_anycast_addr, hostname, last_ip4_address);
 
@@ -303,7 +304,7 @@ nm_dhcp_manager_start_ip4 (NMDhcpManager *self,
 
 	if (send_hostname)
 		hostname = get_send_hostname (self, dhcp_hostname);
-	return client_start (self, iface, ifindex, hwaddr, uuid, priority, FALSE,
+	return client_start (self, iface, ifindex, hwaddr, uuid, priority, FALSE, NULL,
 	                     dhcp_client_id, timeout, dhcp_anycast_addr, hostname,
 	                     FALSE, 0, last_ip_address);
 }
@@ -314,6 +315,7 @@ nm_dhcp_manager_start_ip6 (NMDhcpManager *self,
                            const char *iface,
                            int ifindex,
                            const GByteArray *hwaddr,
+                           const struct in6_addr *ll_addr,
                            const char *uuid,
                            guint32 priority,
                            gboolean send_hostname,
@@ -330,7 +332,7 @@ nm_dhcp_manager_start_ip6 (NMDhcpManager *self,
 	if (send_hostname)
 		hostname = get_send_hostname (self, dhcp_hostname);
 	return client_start (self, iface, ifindex, hwaddr, uuid, priority, TRUE,
-	                     NULL, timeout, dhcp_anycast_addr, hostname, info_only,
+	                     ll_addr, NULL, timeout, dhcp_anycast_addr, hostname, info_only,
 	                     privacy, NULL);
 }
 

src/dhcp-manager/nm-dhcp-manager.h

@@ -67,6 +67,7 @@ NMDhcpClient * nm_dhcp_manager_start_ip6     (NMDhcpManager *manager,
                                               const char *iface,
                                               int ifindex,
                                               const GByteArray *hwaddr,
+                                              const struct in6_addr *ll_addr,
                                               const char *uuid,
                                               guint32 priority,
                                               gboolean send_hostname,

src/dhcp-manager/nm-dhcp-systemd.c

@@ -691,6 +691,7 @@ dhcp6_event_cb (sd_dhcp6_client *client, int event, gpointer user_data)
 static gboolean
 ip6_start (NMDhcpClient *client,
            const char *dhcp_anycast_addr,
+           const struct in6_addr *ll_addr,
            gboolean info_only,
            NMSettingIP6ConfigPrivacy privacy,
            const GByteArray *duid)