/*
 * Copyright (c) 1988, 1989, 1993
 *      The Regents of the University of California.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 *      @(#)radix.h     8.2 (Berkeley) 10/31/94
 * $FreeBSD: src/sys/net/radix.h,v 1.16.2.1 2000/05/03 19:17:11 wollman Exp $
 */

#ifndef _NET_RADIX_H_
#define _NET_RADIX_H_

#include <sys/types.h>

/*
 * Radix search tree node layout.
 */

struct radix_node {
        struct  radix_mask *rn_mklist;  /* masks contained in subtree */
        struct  radix_node *rn_parent;  /* parent */
        int     rn_bit;         /* node: bit offset; leaf: -1-index(netmask) */
        u_char  rn_flags;       /* enumerated next */
#define RNF_NORMAL      1       /* leaf contains normal route */
#define RNF_ROOT        2       /* leaf is root node (embedded in the tree) */
#define RNF_ACTIVE      4       /* node is alive (for rtfree) */
        union {
                /* leaf-only data: */
                struct {
                        /* object of search; point to the key passed by the
                         * caller */
                        const u_char *rn_Key;
                        /* optional netmask; if present, point to the rn_key
                         * of a node in the mask tree */
                        const u_char *rn_Mask;
                        /* chain of routes with the same key but differnt
                         * netmasks. */
                        struct  radix_node *rn_Dupedkey;
                } rn_leaf;
                /* node-only data: */
                struct {
                        int     rn_Offset;      /* where to start compare */
                        u_char  rn_Bmask;       /* byte mask for bit test */
                        struct  radix_node *rn_Left; /* progeny */
                        struct  radix_node *rn_Right; /* progeny */
                } rn_node;
        }       rn_u;
#ifdef RN_DEBUG
        int rn_info;
        struct radix_node *rn_twin;
        struct radix_node *rn_ybro;
#endif
};

#define rn_dupedkey     rn_u.rn_leaf.rn_Dupedkey
#define rn_key          rn_u.rn_leaf.rn_Key
#define rn_mask         rn_u.rn_leaf.rn_Mask
#define rn_offset       rn_u.rn_node.rn_Offset
#define rn_bmask        rn_u.rn_node.rn_Bmask
#define rn_left         rn_u.rn_node.rn_Left
#define rn_right        rn_u.rn_node.rn_Right

/*
 * We do this statically now because the dynamic initialization
 * occurs too late and has an ordering problem w/ pf preloads
 * vs protocol domains.
 */
#define RN_MAXKEYLEN    32
#define RN_MAXKEYONES   { -1, -1, -1, -1, -1, -1, -1, -1,       \
                          -1, -1, -1, -1, -1, -1, -1, -1,       \
                          -1, -1, -1, -1, -1, -1, -1, -1,       \
                          -1, -1, -1, -1, -1, -1, -1, -1 }

/*
 * Annotations to tree concerning potential routes applying to subtrees.
 */

struct radix_mask {
        int     rm_bit;                 /* bit offset; -1-index(netmask) */
        char    rm_unused;
        u_char  rm_flags;               /* cf. rn_flags */
        struct  radix_mask *rm_next;    /* list of more masks to try */
        union   {
                const u_char *rmu_mask;         /* the mask */
                struct  radix_node *rmu_leaf;   /* for normal routes */
        }       rm_rmu;
        int     rm_refs;                /* # of references to this struct */
};

#define rm_mask rm_rmu.rmu_mask
#define rm_leaf rm_rmu.rmu_leaf

typedef int walktree_f_t (struct radix_node *, void *);
typedef void freenode_f_t (struct radix_node *);

struct radix_node_head {
        struct  radix_node *rnh_treetop;

        /* add based on sockaddr */
        struct  radix_node *(*rnh_addaddr)
                    (const void *key, const void *mask,
                     struct radix_node_head *head, struct radix_node nodes[]);

        /* remove based on sockaddr */
        struct  radix_node *(*rnh_deladdr)
                    (const void *key, const void *mask,
                     struct radix_node_head *head);

        /* locate based on sockaddr */
        struct  radix_node *(*rnh_matchaddr)
                    (const void *key, struct radix_node_head *head);

        /* locate based on sockaddr */
        struct  radix_node *(*rnh_lookup)
                    (const void *key, const void *mask,
                     struct radix_node_head *head);

        /* traverse tree */
        int     (*rnh_walktree)
                    (struct radix_node_head *head, walktree_f_t *f, void *w);

        /* traverse tree below a */
        int     (*rnh_walktree_from)
                    (struct radix_node_head *head, const void *addr,
                     const void *mask, walktree_f_t *f, void *w);

        /*
         * Do something when the last ref drops.
         * A (*rnh_close)() routine
         *      can clear RTF_UP
         *      can remove a route from the radix tree
         *      cannot change the reference count
         *      cannot deallocate the route
         */
        void    (*rnh_close)
                    (struct radix_node *rn, struct radix_node_head *head);

        /*
         * Embedded nodes (flagged with RNF_ROOT) for an empty tree:
         * - left node
         * - top/root node (pointed by rnh_treetop)
         * - right node
         */
        struct  radix_node rnh_nodes[3];

        /* unused entries */
        int     rnh_addrsize;           /* permit, but not require fixed keys */
        int     rnh_pktsize;            /* permit, but not require fixed keys */
        struct  radix_node *(*rnh_addpkt)       /* add based on packet hdr */
                    (const void *v, const void *mask,
                     struct radix_node_head *head, struct radix_node nodes[]);
        struct  radix_node *(*rnh_delpkt)       /* remove based on packet hdr */
                    (const void *v, const void *mask,
                     struct radix_node_head *head);

        /* traverse tree starting from a */
        int     (*rnh_walktree_at)
                    (struct radix_node_head *head, const void *addr,
                     const void *mask, walktree_f_t *f, void *w);

        struct radix_node_head *rnh_maskhead;
};

#ifdef _KERNEL

#ifdef MALLOC_DECLARE
MALLOC_DECLARE(M_RTABLE);
#endif

#define R_Malloc(p, t, n) \
        (p = (t) kmalloc((n), M_RTABLE, M_INTWAIT | M_NULLOK))
#define R_Free(p)       kfree(p, M_RTABLE)

#else /* !_KERNEL */

#include <stdbool.h>

#define R_Malloc(p, t, n)       (p = (t) malloc((n)))
#define R_Free(p)               free(p)

#endif /* _KERNEL */

void                     rn_init(void);
int                      rn_inithead(struct radix_node_head **head,
                                     struct radix_node_head *maskhead,
                                     int off_bytes);
void                     rn_freehead(struct radix_node_head *head);
void                     rn_flush(struct radix_node_head *head,
                                  freenode_f_t *f);
void                     rn_freemask(struct radix_node *rn);
struct radix_node_head  *rn_cpumaskhead(int cpu);
bool                     rn_refines(const void *m, const void *n);
struct radix_node       *rn_addmask(const void *mask, bool search, int skip,
                                    struct radix_node_head *maskhead);
struct radix_node       *rn_addroute(const void *key, const void *mask,
                                     struct radix_node_head *head,
                                     struct radix_node nodes[2]);
struct radix_node       *rn_delete(const void *key, const void *mask,
                                   struct radix_node_head *head);
struct radix_node       *rn_lookup(const void *key, const void *mask,
                                   struct radix_node_head *head);
struct radix_node       *rn_match(const void *key,
                                  struct radix_node_head *head);

#endif /* _NET_RADIX_H_ */