zebra: don't change connected state from zebra/interface.c
Try to avoid changing connected state from zebra/interface.c as this
means making assumptions about kernel behaviour which may be or may
become wrong. This state should rather be updated by events from the
kernel.
Signed-off-by: Christian Franke <chris@opensourcerouting.org>
Signed-off-by: David Lamparter <equinox@opensourcerouting.org>
diff --git a/zebra/interface.c b/zebra/interface.c
index 470df0c..51798ca 100644
--- a/zebra/interface.c
+++ b/zebra/interface.c
@@ -193,6 +193,9 @@
ifc = listgetdata (listhead (addr_list));
zebra_interface_address_delete_update (ifp, ifc);
UNSET_FLAG (ifc->flags, ZEBRA_IFA_SECONDARY);
+ /* XXX: Linux kernel removes all the secondary addresses when the primary
+ * address is removed. We could try to work around that, though this is
+ * non-trivial. */
zebra_interface_address_add_update (ifp, ifc);
}
@@ -296,16 +299,23 @@
{
if (! if_is_up (ifp))
{
- /* XXX: WTF is it trying to set flags here?
- * caller has just gotten a new interface, has been
- * handed the flags already. This code has no business
- * trying to override administrative status of the interface.
- * The only call path to here which doesn't originate from
- * kernel event is irdp - what on earth is it trying to do?
- *
- * further RUNNING is not a settable flag on any system
- * I (paulj) am aware of.
- */
+ /* Assume zebra is configured like following:
+ *
+ * interface gre0
+ * ip addr 192.0.2.1/24
+ * !
+ *
+ * As soon as zebra becomes first aware that gre0 exists in the
+ * kernel, it will set gre0 up and configure its addresses.
+ *
+ * (This may happen at startup when the interface already exists
+ * or during runtime when the interface is added to the kernel)
+ *
+ * XXX: IRDP code is calling here via if_add_update - this seems
+ * somewhat weird.
+ * XXX: RUNNING is not a settable flag on any system
+ * I (paulj) am aware of.
+ */
if_set_flags (ifp, IFF_UP | IFF_RUNNING);
if_refresh (ifp);
}
@@ -318,23 +328,17 @@
continue;
}
- /* Add to subnet chain list. */
- if_subnet_add (ifp, ifc);
-
SET_FLAG (ifc->conf, ZEBRA_IFC_QUEUED);
- SET_FLAG (ifc->conf, ZEBRA_IFC_REAL);
-
- zebra_interface_address_add_update (ifp, ifc);
-
- if (if_is_operative(ifp))
- connected_up_ipv4 (ifp, ifc);
+ /* The address will be advertised to zebra clients when the notification
+ * from the kernel has been received.
+ * It will also be added to the interface's subnet list then. */
}
#ifdef HAVE_IPV6
if (p->family == AF_INET6)
{
if (! if_is_up (ifp))
{
- /* XXX: See long comment above */
+ /* See long comment above */
if_set_flags (ifp, IFF_UP | IFF_RUNNING);
if_refresh (ifp);
}
@@ -346,13 +350,10 @@
safe_strerror(errno));
continue;
}
+
SET_FLAG (ifc->conf, ZEBRA_IFC_QUEUED);
- SET_FLAG (ifc->conf, ZEBRA_IFC_REAL);
-
- zebra_interface_address_add_update (ifp, ifc);
-
- if (if_is_operative(ifp))
- connected_up_ipv6 (ifp, ifc);
+ /* The address will be advertised to zebra clients when the notification
+ * from the kernel has been received. */
}
#endif /* HAVE_IPV6 */
}
@@ -450,9 +451,11 @@
ifc = listgetdata (anode);
p = ifc->address;
-
connected_down_ipv4 (ifp, ifc);
+ /* XXX: We have to send notifications here explicitly, because we destroy
+ * the ifc before receiving the notification about the address being deleted.
+ */
zebra_interface_address_delete_update (ifp, ifc);
UNSET_FLAG (ifc->conf, ZEBRA_IFC_REAL);
@@ -1251,19 +1254,10 @@
return CMD_WARNING;
}
- /* Add to subnet chain list (while marking secondary attribute). */
- if_subnet_add (ifp, ifc);
-
- /* IP address propery set. */
SET_FLAG (ifc->conf, ZEBRA_IFC_QUEUED);
- SET_FLAG (ifc->conf, ZEBRA_IFC_REAL);
-
- /* Update interface address information to protocol daemon. */
- zebra_interface_address_add_update (ifp, ifc);
-
- /* If interface is up register connected route. */
- if (if_is_operative(ifp))
- connected_up_ipv4 (ifp, ifc);
+ /* The address will be advertised to zebra clients when the notification
+ * from the kernel has been received.
+ * It will also be added to the subnet chain list, then. */
}
return CMD_SUCCESS;
@@ -1317,35 +1311,9 @@
safe_strerror(errno), VTY_NEWLINE);
return CMD_WARNING;
}
- /* success! call returned that the address deletion went through.
- * this is a synchronous operation, so we know it succeeded and can
- * now update all internal state. */
-
- /* the HAVE_NETLINK check is only here because, on BSD, although the
- * call above is still synchronous, we get a second confirmation later
- * through the route socket, and we don't want to touch that behaviour
- * for now. It should work without the #ifdef, but why take the risk...
- * -- equinox 2012-07-13 */
UNSET_FLAG (ifc->conf, ZEBRA_IFC_QUEUED);
-#ifdef HAVE_NETLINK
-
- /* Remove connected route. */
- connected_down_ipv4 (ifp, ifc);
-
- /* Redistribute this information. */
- zebra_interface_address_delete_update (ifp, ifc);
-
- /* IP address propery set. */
- UNSET_FLAG (ifc->conf, ZEBRA_IFC_REAL);
-
- /* remove from interface, remark secondaries */
- if_subnet_delete (ifp, ifc);
-
- /* Free address information. */
- listnode_delete (ifp->connected, ifc);
- connected_free (ifc);
-#endif
-
+ /* we will receive a kernel notification about this route being removed.
+ * this will trigger its removal from the connected list. */
return CMD_SUCCESS;
}
@@ -1462,16 +1430,9 @@
return CMD_WARNING;
}
- /* IP address propery set. */
SET_FLAG (ifc->conf, ZEBRA_IFC_QUEUED);
- SET_FLAG (ifc->conf, ZEBRA_IFC_REAL);
-
- /* Update interface address information to protocol daemon. */
- zebra_interface_address_add_update (ifp, ifc);
-
- /* If interface is up register connected route. */
- if (if_is_operative(ifp))
- connected_up_ipv6 (ifp, ifc);
+ /* The address will be advertised to zebra clients when the notification
+ * from the kernel has been received. */
}
return CMD_SUCCESS;
@@ -1527,17 +1488,8 @@
}
UNSET_FLAG (ifc->conf, ZEBRA_IFC_QUEUED);
-
- /* Redistribute this information. */
- zebra_interface_address_delete_update (ifp, ifc);
-
- /* Remove connected route. */
- connected_down_ipv6 (ifp, ifc);
-
- /* Free address information. */
- listnode_delete (ifp->connected, ifc);
- connected_free (ifc);
-
+ /* This information will be propagated to the zclients when the
+ * kernel notification is received. */
return CMD_SUCCESS;
}