bgpd: rewrite 'bgp label vpn export' command

The original 'bgp label vpn export' code is confusing,
the 'no form' actions are mixed with the positive form.

Fix this by rewriting the code.

Signed-off-by: Philippe Guibert <philippe.guibert@6wind.com>

diff --git a/bgpd/bgp_vty.c b/bgpd/bgp_vty.c
index 8144d6e7b3bc2b3fda85ad9ce8db64b0528086c2..48eaf1ed777be93ab8abbbbc0c65b98b9293e4f4 100644 (file)
--- a/bgpd/bgp_vty.c
+++ b/bgpd/bgp_vty.c
@@ -9434,7 +9434,7 @@ DEFPY (af_label_vpn_export,
        "Automatically assign a label\n")
 {
        VTY_DECLVAR_CONTEXT(bgp, bgp);
-       mpls_label_t label = MPLS_LABEL_NONE;
+       mpls_label_t label = (mpls_label_t)label_val;
        afi_t afi;
        int idx = 0;
        bool yes = true;
@@ -9442,24 +9442,28 @@ DEFPY (af_label_vpn_export,
        if (argv_find(argv, argc, "no", &idx))
                yes = false;
 
-       /* If "no ...", squash trailing parameter */
-       if (!yes)
-               label_auto = NULL;
-
-       if (yes) {
-               if (!label_auto)
-                       label = label_val; /* parser should force unsigned */
-       }
-
        afi = vpn_policy_getafi(vty, bgp, false);
        if (afi == AFI_MAX)
                return CMD_WARNING_CONFIG_FAILED;
 
-
-       if (label_auto && CHECK_FLAG(bgp->vpn_policy[afi].flags,
-                                    BGP_VPN_POLICY_TOVPN_LABEL_AUTO))
-               /* no change */
-               return CMD_SUCCESS;
+       if (yes) {
+               if (label_auto && CHECK_FLAG(bgp->vpn_policy[afi].flags,
+                                            BGP_VPN_POLICY_TOVPN_LABEL_AUTO))
+                       /* no change */
+                       return CMD_SUCCESS;
+               if (!label_auto && label == bgp->vpn_policy[afi].tovpn_label)
+                       /* no change */
+                       return CMD_SUCCESS;
+       } else {
+               if (label_auto && !CHECK_FLAG(bgp->vpn_policy[afi].flags,
+                                             BGP_VPN_POLICY_TOVPN_LABEL_AUTO))
+                       /* no match */
+                       return CMD_WARNING_CONFIG_FAILED;
+               if (!label_auto && label_val &&
+                   label != bgp->vpn_policy[afi].tovpn_label)
+                       /* no change */
+                       return CMD_WARNING_CONFIG_FAILED;
+       }
 
        /*
         * pre-change: un-export vpn routes (vpn->vrf routes unaffected)
@@ -9467,9 +9471,9 @@ DEFPY (af_label_vpn_export,
        vpn_leak_prechange(BGP_VPN_POLICY_DIR_TOVPN, afi,
                           bgp_get_default(), bgp);
 
-       if (!label_auto && CHECK_FLAG(bgp->vpn_policy[afi].flags,
-                                     BGP_VPN_POLICY_TOVPN_LABEL_AUTO)) {
-
+       /* release any previous auto label */
+       if (CHECK_FLAG(bgp->vpn_policy[afi].flags,
+                      BGP_VPN_POLICY_TOVPN_LABEL_AUTO)) {
                if (bgp->vpn_policy[afi].tovpn_label != MPLS_LABEL_NONE) {
 
                        /*
@@ -9486,16 +9490,25 @@ DEFPY (af_label_vpn_export,
                                       &bgp->vpn_policy[afi],
                                       bgp->vpn_policy[afi].tovpn_label);
                }
-               UNSET_FLAG(bgp->vpn_policy[afi].flags,
-                          BGP_VPN_POLICY_TOVPN_LABEL_AUTO);
        }
 
-       bgp->vpn_policy[afi].tovpn_label = label;
-       if (label_auto) {
-               SET_FLAG(bgp->vpn_policy[afi].flags,
-                        BGP_VPN_POLICY_TOVPN_LABEL_AUTO);
-               bgp_lp_get(LP_TYPE_VRF, &bgp->vpn_policy[afi],
-                          vpn_leak_label_callback);
+       if (yes) {
+               if (label_auto) {
+                       SET_FLAG(bgp->vpn_policy[afi].flags,
+                                BGP_VPN_POLICY_TOVPN_LABEL_AUTO);
+                       /* fetch a label */
+                       bgp->vpn_policy[afi].tovpn_label = MPLS_LABEL_NONE;
+                       bgp_lp_get(LP_TYPE_VRF, &bgp->vpn_policy[afi],
+                                  vpn_leak_label_callback);
+               } else {
+                       UNSET_FLAG(bgp->vpn_policy[afi].flags,
+                                  BGP_VPN_POLICY_TOVPN_LABEL_AUTO);
+                       bgp->vpn_policy[afi].tovpn_label = label;
+               }
+       } else {
+               UNSET_FLAG(bgp->vpn_policy[afi].flags,
+                          BGP_VPN_POLICY_TOVPN_LABEL_AUTO);
+               bgp->vpn_policy[afi].tovpn_label = MPLS_LABEL_NONE;
        }
 
        /* post-change: re-export vpn routes */