ospf6d: Support for nssa in ospfv3

The following is implemented.
1. Configuring area as NSSA.
2. Generating Type 7 LSA.
3. Conversion of Type 7 to Type 5 ( Default Behavior).
4. NSSA ABR selection.

Reviewed-by: Rafael Zalamena <rzalamena@opensourcerouting.org>
Co-authored-by: Kaushik <kaushiknath.null@gmail.com>
Co-authored-by: Soman K.S <somanks@gmail.com>
Signed-off-by: Kaushik <kaushiknath.null@gmail.com>

1 files changed, 76 insertions, 0 deletions

diff --git a/ospf6d/ospf6_nssa.h b/ospf6d/ospf6_nssa.h
new file mode 100644
index 0000000000..a171d76d44
--- /dev/null
+++ b/ospf6d/ospf6_nssa.h
@@ -0,0 +1,76 @@
+/*
+ * OSPFv3 Not So Stubby Area implementation.
+ *
+ * Copyright (C) 2021 Kaushik Nath
+ * Copyright (C) 2021 Soman K.S
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#ifndef OSPF6_NSSA_H
+#define OSPF6_NSSA_H
+
+#define OSPF6_OPTION_NP         0x08
+#define OSPF6_LS_INFINITY       0xffffff
+
+#define OSPF6_OPT_N             (1 << 3) /* Handling Type-7 LSA Capability */
+
+#define OSPF6_DEBUG_NSSA        0x09
+/* Debug option */
+extern unsigned char config_debug_ospf6_nssa;
+
+#define OSPF6_DEBUG_NSSA_ON() (config_debug_ospf6_nssa = 1)
+#define OSPF6_DEBUG_NSSA_OFF() (config_debug_ospf6_nssa = 0)
+#define IS_OSPF6_DEBUG_NSSA config_debug_ospf6_nssa
+
+#define CHECK_LSA_TYPE_1_TO_5_OR_7(type)                                       \
+	((type == OSPF6_ROUTER_LSA_MIN_SIZE)                                   \
+	 || (type == OSPF6_NETWORK_LSA_MIN_SIZE)                               \
+	 || (type == OSPF6_LINK_LSA_MIN_SIZE)                                  \
+	 || (type == OSPF6_INTRA_PREFIX_LSA_MIN_SIZE)                          \
+	 || (type == OSPF6_AS_NSSA_LSA))
+
+#define OSPF6_LSA_APPROVED      0x08
+#define OSPF6_LSA_LOCAL_XLT     0x40
+
+#define OSPF6_ABR_TASK_DELAY    7
+
+int ospf6_area_nssa_no_summary_set(struct ospf6 *ospf6, struct in_addr area_id);
+int ospf6_area_nssa_unset(struct ospf6 *ospf6, struct ospf6_area *area);
+int ospf6_area_nssa_set(struct ospf6 *ospf6, struct ospf6_area *area);
+
+extern void ospf6_nssa_lsa_flush(struct ospf6 *ospf6, struct prefix_ipv6 *p);
+extern struct ospf6_lsa *ospf6_translated_nssa_refresh(struct ospf6_area *,
+						       struct ospf6_lsa *,
+						       struct ospf6_lsa *);
+extern struct ospf6_lsa *ospf6_translated_nssa_originate(struct ospf6_area *,
+							 struct ospf6_lsa *);
+
+extern void ospf6_asbr_nssa_redist_task(struct ospf6 *ospf6);
+
+extern void ospf6_schedule_abr_task(struct ospf6 *ospf6);
+void ospf6_asbr_prefix_readvertise(struct ospf6 *ospf6);
+extern void ospf6_nssa_lsa_originate(struct ospf6_route *route,
+				     struct ospf6_area *area);
+extern void install_element_ospf6_debug_nssa(void);
+int ospf6_redistribute_check(struct ospf6 *ospf6, struct ospf6_route *route,
+			     int type);
+extern int ospf6_abr_translate_nssa(struct ospf6_area *area,
+				    struct ospf6_lsa *lsa);
+extern void ospf6_abr_check_translate_nssa(struct ospf6_area *area,
+					   struct ospf6_lsa *lsa);
+extern void ospf6_abr_nssa_check_status(struct ospf6 *ospf6);
+extern void config_write_ospf6_debug_nssa(struct vty *vty);
+#endif /* OSPF6_NSSA_H */