diff --git a/ospfd/ospf_interface.h b/ospfd/ospf_interface.h
new file mode 100644
index 0000000..6dc01ae
--- /dev/null
+++ b/ospfd/ospf_interface.h
@@ -0,0 +1,245 @@
+/*
+ * OSPF Interface functions.
+ * Copyright (C) 1999 Toshiaki Takada
+ *
+ * This file is part of GNU Zebra.
+ * 
+ * GNU Zebra 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, or (at your
+ * option) any later version.
+ *
+ * GNU Zebra 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 GNU Zebra; see the file COPYING.  If not, write to the
+ * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ * Boston, MA 02111-1307, USA.
+ */
+
+#ifndef _ZEBRA_OSPF_INTERFACE_H
+#define _ZEBRA_OSPF_INTERFACE_H
+
+#define OSPF_AUTH_SIMPLE_SIZE           8
+#define OSPF_AUTH_MD5_SIZE             16
+
+#define IF_OSPF_IF_INFO(I) ((struct ospf_if_info *)((I)->info))
+#define IF_DEF_PARAMS(I) (IF_OSPF_IF_INFO (I)->def_params)
+#define IF_OIFS(I)  (IF_OSPF_IF_INFO (I)->oifs)
+#define IF_OIFS_PARAMS(I) (IF_OSPF_IF_INFO (I)->params)
+			    
+#define OSPF_IF_PARAM_CONFIGURED(S, P) ((S) && (S)->P##__config)
+#define OSPF_IF_PARAM(O, P) \
+        (OSPF_IF_PARAM_CONFIGURED ((O)->params, P)?\
+                        (O)->params->P:IF_DEF_PARAMS((O)->ifp)->P)
+
+#define DECLARE_IF_PARAM(T, P) T P; u_char P##__config:1
+#define UNSET_IF_PARAM(S, P) ((S)->P##__config) = 0
+#define SET_IF_PARAM(S, P) ((S)->P##__config) = 1
+
+struct ospf_if_params
+{
+  DECLARE_IF_PARAM (u_int32_t, transmit_delay); /* Interface Transmisson Delay */
+  DECLARE_IF_PARAM (u_int32_t, output_cost_cmd);/* Command Interface Output Cost */
+  DECLARE_IF_PARAM (u_int32_t, retransmit_interval); /* Retransmission Interval */
+  DECLARE_IF_PARAM (u_char, passive_interface);      /* OSPF Interface is passive */
+  DECLARE_IF_PARAM (u_char, priority);               /* OSPF Interface priority */
+  DECLARE_IF_PARAM (u_char, type);                   /* type of interface */
+#define OSPF_IF_ACTIVE                  0
+#define OSPF_IF_PASSIVE		        1
+  
+  DECLARE_IF_PARAM (u_int32_t, v_hello);             /* Hello Interval */
+  DECLARE_IF_PARAM (u_int32_t, v_wait);              /* Router Dead Interval */
+
+  /* Authentication data. */
+  u_char auth_simple[OSPF_AUTH_SIMPLE_SIZE + 1];       /* Simple password. */
+  u_char auth_simple__config:1;
+  
+  DECLARE_IF_PARAM (list, auth_crypt);                 /* List of Auth cryptographic data. */
+  DECLARE_IF_PARAM (int, auth_type);               /* OSPF authentication type */
+};
+
+struct ospf_if_info
+{
+  struct ospf_if_params *def_params;
+  struct route_table *params;
+  struct route_table *oifs;
+};
+
+struct ospf_interface;
+
+struct ospf_vl_data
+{
+  struct in_addr    vl_peer;	   /* Router-ID of the peer for VLs. */
+  struct in_addr    vl_area_id;	   /* Transit area for this VL. */
+  int format;                      /* area ID format */
+  struct ospf_interface *vl_oi;	   /* Interface data structure for the VL. */
+  struct ospf_interface *out_oi;   /* The interface to go out. */
+  struct in_addr    peer_addr;	   /* Address used to reach the peer. */
+  u_char flags;
+};
+
+
+#define OSPF_VL_MAX_COUNT 256
+#define OSPF_VL_MTU	  1500
+
+#define OSPF_VL_FLAG_APPROVED 0x01
+
+struct crypt_key
+{
+  u_char key_id;
+  u_char auth_key[OSPF_AUTH_MD5_SIZE + 1];
+};
+
+/* OSPF interface structure. */
+struct ospf_interface
+{
+  /* This interface's parent ospf instance. */
+  struct ospf *ospf;
+
+  /* OSPF Area. */
+  struct ospf_area *area;
+
+  /* Interface data from zebra. */
+  struct interface *ifp;
+  struct ospf_vl_data *vl_data;		/* Data for Virtual Link */
+  
+  /* Packet send buffer. */
+  struct ospf_fifo *obuf;		/* Output queue */
+
+  /* OSPF Network Type. */
+  u_char type;
+#define OSPF_IFTYPE_NONE		0
+#define OSPF_IFTYPE_POINTOPOINT		1
+#define OSPF_IFTYPE_BROADCAST		2
+#define OSPF_IFTYPE_NBMA		3
+#define OSPF_IFTYPE_POINTOMULTIPOINT	4
+#define OSPF_IFTYPE_VIRTUALLINK		5
+#define OSPF_IFTYPE_LOOPBACK            6
+#define OSPF_IFTYPE_MAX			7
+
+  /* State of Interface State Machine. */
+  u_char state;
+
+  struct prefix *address;		/* Interface prefix */
+  struct connected *connected;          /* Pointer to connected */ 
+
+  /* Configured varables. */
+  struct ospf_if_params *params;
+  u_int32_t crypt_seqnum;		/* Cryptographic Sequence Number */ 
+  u_int32_t output_cost;	        /* Acutual Interface Output Cost */
+
+  /* Neighbor information. */
+  struct route_table *nbrs;             /* OSPF Neighbor List */
+  struct ospf_neighbor *nbr_self;	/* Neighbor Self */
+#define DR(I)			((I)->nbr_self->d_router)
+#define BDR(I)			((I)->nbr_self->bd_router)
+#define OPTIONS(I)		((I)->nbr_self->options)
+#define PRIORITY(I)		((I)->nbr_self->priority)
+
+  /* List of configured NBMA neighbor. */
+  list nbr_nbma;
+
+  /* self-originated LSAs. */
+  struct ospf_lsa *network_lsa_self;	/* network-LSA. */
+#ifdef HAVE_OPAQUE_LSA
+  list opaque_lsa_self;			/* Type-9 Opaque-LSAs */
+#endif /* HAVE_OPAQUE_LSA */
+
+  struct route_table *ls_upd_queue;
+
+  list ls_ack;				/* Link State Acknowledgment list. */
+  
+  struct
+  {
+    list ls_ack;
+    struct in_addr dst;
+  } ls_ack_direct;
+
+  /* Timer values. */
+  u_int32_t v_ls_ack;			/* Delayed Link State Acknowledgment */
+
+  /* Threads. */
+  struct thread *t_hello;               /* timer */
+  struct thread *t_wait;                /* timer */
+  struct thread *t_ls_ack;              /* timer */
+  struct thread *t_ls_ack_direct;       /* event */
+  struct thread *t_ls_upd_event;        /* event */
+  struct thread *t_network_lsa_self;    /* self-originated network-LSA
+                                           reflesh thread. timer */
+#ifdef HAVE_OPAQUE_LSA
+  struct thread *t_opaque_lsa_self;     /* Type-9 Opaque-LSAs */
+#endif /* HAVE_OPAQUE_LSA */
+
+  int on_write_q;
+  
+  /* Statistics fields. */
+  u_int32_t hello_in;	        /* Hello message input count. */
+  u_int32_t hello_out;	        /* Hello message output count. */
+  u_int32_t db_desc_in;         /* database desc. message input count. */
+  u_int32_t db_desc_out;        /* database desc. message output count. */
+  u_int32_t ls_req_in;          /* LS request message input count. */
+  u_int32_t ls_req_out;         /* LS request message output count. */
+  u_int32_t ls_upd_in;          /* LS update message input count. */
+  u_int32_t ls_upd_out;         /* LS update message output count. */
+  u_int32_t ls_ack_in;          /* LS Ack message input count. */
+  u_int32_t ls_ack_out;         /* LS Ack message output count. */
+  u_int32_t discarded;		/* discarded input count by error. */
+  u_int32_t state_change;	/* Number of status change. */
+
+  u_int full_nbrs;
+};
+
+/* Prototypes. */
+char *ospf_if_name (struct ospf_interface *);
+struct ospf_interface *ospf_if_new ();
+void ospf_if_cleanup (struct ospf_interface *);
+void ospf_if_free (struct ospf_interface *);
+int ospf_if_up (struct ospf_interface *);
+int ospf_if_down (struct ospf_interface *);
+
+int ospf_if_is_up (struct ospf_interface *);
+struct ospf_interface *ospf_if_lookup_by_name (char *);
+struct ospf_interface *ospf_if_lookup_by_local_addr (struct interface *, struct in_addr);
+struct ospf_interface *ospf_if_lookup_by_prefix (struct prefix_ipv4 *);
+struct ospf_interface *ospf_if_addr_local (struct in_addr src);
+struct ospf_interface *ospf_if_lookup_recv_interface (struct in_addr src);
+struct ospf_interface *ospf_if_is_configured (struct in_addr *);
+
+struct ospf_if_params *ospf_lookup_if_params (struct interface *, struct in_addr);
+struct ospf_if_params *ospf_get_if_params (struct interface *, struct in_addr);
+void ospf_del_if_params (struct ospf_if_params *);
+void ospf_free_if_params (struct interface *, struct in_addr);
+void ospf_if_update_params (struct interface *, struct in_addr);
+
+int ospf_if_new_hook (struct interface *);
+void ospf_if_init ();
+void ospf_if_stream_set (struct ospf_interface *);
+void ospf_if_stream_unset (struct ospf_interface *);
+void ospf_if_reset_variables (struct ospf_interface *);
+int ospf_if_is_enable (struct ospf_interface *);
+int ospf_if_get_output_cost (struct ospf_interface *);
+void ospf_if_recalculate_output_cost (struct interface *);
+
+struct ospf_interface *ospf_vl_new (struct ospf_vl_data *);
+struct ospf_vl_data *ospf_vl_data_new (struct ospf_area *, struct in_addr);
+struct ospf_vl_data *ospf_vl_lookup (struct ospf_area *, struct in_addr);
+void ospf_vl_data_free (struct ospf_vl_data *);
+void ospf_vl_add (struct ospf_vl_data *);
+void ospf_vl_delete (struct ospf_vl_data *);
+void ospf_vl_up_check (struct ospf_area *, struct in_addr, struct vertex *);
+void ospf_vl_unapprove ();
+void ospf_vl_shut_unapproved ();
+int ospf_full_virtual_nbrs (struct ospf_area *);
+int ospf_vls_in_area (struct ospf_area *);
+
+struct crypt_key *ospf_crypt_key_lookup (list, u_char);
+struct crypt_key *ospf_crypt_key_new ();
+void ospf_crypt_key_add (list, struct crypt_key *);
+int ospf_crypt_key_delete (list, u_char key_id);
+
+
+#endif /* _ZEBRA_OSPF_INTERFACE_H */