xref: /freebsd/sys/netpfil/ipfw/ip_fw_table_algo.c (revision 8ebca97f5ef134b3d7eb67626cb70283347e529f)

/*-
 * Copyright (c) 2014 Yandex LLC
 * Copyright (c) 2014 Alexander V. Chernikov
 *
 * 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.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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.
 */

#include <sys/cdefs.h>
__FBSDID("$FreeBSD: projects/ipfw/sys/netpfil/ipfw/ip_fw_table.c 267384 2014-06-12 09:59:11Z melifaro $");

/*
 * Lookup table algorithms.
 *
 */

#include "opt_ipfw.h"
#include "opt_inet.h"
#ifndef INET
#error IPFIREWALL requires INET.
#endif /* INET */
#include "opt_inet6.h"

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/malloc.h>
#include <sys/kernel.h>
#include <sys/lock.h>
#include <sys/rwlock.h>
#include <sys/rmlock.h>
#include <sys/socket.h>
#include <sys/queue.h>
#include <net/if.h>	/* ip_fw.h requires IFNAMSIZ */
#include <net/radix.h>
#include <net/route.h>

#include <netinet/in.h>
#include <netinet/ip_var.h>	/* struct ipfw_rule_ref */
#include <netinet/ip_fw.h>

#include <netpfil/ipfw/ip_fw_private.h>
#include <netpfil/ipfw/ip_fw_table.h>


/*
 * IPFW table lookup algorithms.
 *
 * What is needed to add another table algo?
 *
 * Algo init:
 * * struct table_algo has to be filled with:
 *   name: "type:algoname" format, e.g. "addr:radix". Currently
 *     there are the following types: "addr", "iface", "number" and "flow".
 *   type: one of IPFW_TABLE_* types
 *   flags: one or more TA_FLAGS_*
 *   ta_buf_size: size of structure used to store add/del item state.
 *     Needs to be less than TA_BUF_SZ.
 *   callbacks: see below for description.
 * * ipfw_add_table_algo / ipfw_del_table_algo has to be called
 *
 * Callbacks description:
 *
 * -init: request to initialize new table instance.
 * typedef int (ta_init)(struct ip_fw_chain *ch, void **ta_state,
 *     struct table_info *ti, char *data, uint8_t tflags);
 * MANDATORY, unlocked. (M_WAITOK). Returns 0 on success.
 *
 *  Allocate all structures needed for normal operations.
 *  * Caller may want to parse @data for some algo-specific
 *    options provided by userland.
 *  * Caller may want to save configuration state pointer to @ta_state
 *  * Caller needs to save desired runtime structure pointer(s)
 *    inside @ti fields. Note that it is not correct to save
 *    @ti pointer at this moment. Use -change_ti hook for that.
 *  * Caller has to fill in ti->lookup to appropriate function
 *    pointer.
 *
 *
 *
 * -destroy: request to destroy table instance.
 * typedef void (ta_destroy)(void *ta_state, struct table_info *ti);
 * MANDATORY, may be locked (UH+WLOCK). (M_NOWAIT).
 *
 * Frees all table entries and all tables structures allocated by -init.
 *
 *
 *
 * -prepare_add: request to allocate state for adding new entry.
 * typedef int (ta_prepare_add)(struct ip_fw_chain *ch, struct tentry_info *tei,
 *     void *ta_buf);
 * MANDATORY, unlocked. (M_WAITOK). Returns 0 on success.
 *
 * Allocates state and fills it in with all necessary data (EXCEPT value)
 * from @tei to minimize operations needed to be done under WLOCK.
 * "value" field has to be copied to new entry in @add callback.
 * Buffer ta_buf of size ta->ta_buf_sz may be used to store
 * allocated state.
 *
 *
 *
 * -prepare_del: request to set state for deleting existing entry.
 * typedef int (ta_prepare_del)(struct ip_fw_chain *ch, struct tentry_info *tei,
 *     void *ta_buf);
 * MANDATORY, locked, UH. (M_NOWAIT). Returns 0 on success.
 *
 * Buffer ta_buf of size ta->ta_buf_sz may be used to store
 * allocated state. Caller should use on-stack ta_buf allocation
 * instead of doing malloc().
 *
 *
 *
 * -add: request to insert new entry into runtime/config structures.
 *  typedef int (ta_add)(void *ta_state, struct table_info *ti,
 *     struct tentry_info *tei, void *ta_buf, uint32_t *pnum);
 * MANDATORY, UH+WLOCK. (M_NOWAIT). Returns 0 on success.
 *
 * Insert new entry using previously-allocated state in @ta_buf.
 * * @tei may have the following flags:
 *   TEI_FLAGS_UPDATE: request to add or update entry.
 *   TEI_FLAGS_DONTADD: request to update (but not add) entry.
 * * Caller is required to do the following:
 *   copy real entry value from @tei
 *   entry added: return 0, set 1 to @pnum
 *   entry updated: return 0, store 0 to @pnum, store old value in @tei,
 *     add TEI_FLAGS_UPDATED flag to @tei.
 *   entry exists: return EEXIST
 *   entry not found: return ENOENT
 *   other error: return non-zero error code.
 *
 *
 *
 * -del: request to delete existing entry from runtime/config structures.
 *  typedef int (ta_del)(void *ta_state, struct table_info *ti,
 *     struct tentry_info *tei, void *ta_buf, uint32_t *pnum);
 *  MANDATORY, UH+WLOCK. (M_NOWAIT). Returns 0 on success.
 *
 *  Delete entry using previously set up in @ta_buf.
 * * Caller is required to do the following:
 *   entry deleted: return 0, set 1 to @pnum, store old value in @tei.
 *   entry not found: return ENOENT
 *   other error: return non-zero error code.
 *
 *
 *
 * -flush_entry: flush entry state created by -prepare_add / -del / others
 *  typedef void (ta_flush_entry)(struct ip_fw_chain *ch,
 *      struct tentry_info *tei, void *ta_buf);
 *  MANDATORY, may be locked. (M_NOWAIT).
 *
 *  Delete state allocated by:
 *  -prepare_add (-add returned EEXIST|UPDATED)
 *  -prepare_del (if any)
 *  -del
 *  * Caller is required to handle empty @ta_buf correctly.
 *
 *
 * -find_tentry: finds entry specified by key @tei
 *  typedef int ta_find_tentry(void *ta_state, struct table_info *ti,
 *      ipfw_obj_tentry *tent);
 *  OPTIONAL, locked (UH). (M_NOWAIT). Returns 0 on success.
 *
 *  Finds entry specified by given key.
 *  * Caller is requred to do the following:
 *    entry found: returns 0, export entry to @tent
 *    entry not found: returns ENOENT
 *
 *
 * -need_modify: checks if @ti has enough space to hold another @count items.
 *  typedef int (ta_need_modify)(void *ta_state, struct table_info *ti,
 *      uint32_t count, uint64_t *pflags);
 *  OPTIONAL, locked (UH). (M_NOWAIT). Returns 0 if has.
 *
 *  Checks if given table has enough space to add @count items without
 *  resize. Caller may use @pflags to store desired modification data.
 *
 *
 *
 * -prepare_mod: allocate structures for table modification.
 *  typedef int (ta_prepare_mod)(void *ta_buf, uint64_t *pflags);
 * OPTIONAL(need_modify), unlocked. (M_WAITOK). Returns 0 on success.
 *
 * Allocate all needed state for table modification. Caller
 * should use `struct mod_item` to store new state in @ta_buf.
 * Up to TA_BUF_SZ (128 bytes) can be stored in @ta_buf.
 *
 *
 *
 * -fill_mod: copy some data to new state/
 *  typedef int (ta_fill_mod)(void *ta_state, struct table_info *ti,
 *      void *ta_buf, uint64_t *pflags);
 * OPTIONAL(need_modify), locked (UH). (M_NOWAIT). Returns 0 on success.
 *
 * Copy as much data as we can to minimize changes under WLOCK.
 * For example, array can be merged inside this callback.
 *
 *
 *
 * -modify: perform final modification.
 *  typedef void (ta_modify)(void *ta_state, struct table_info *ti,
 *      void *ta_buf, uint64_t pflags);
 * OPTIONAL(need_modify), locked (UH+WLOCK). (M_NOWAIT).
 *
 * Performs all changes necessary to switch to new structures.
 * * Caller should save old pointers to @ta_buf storage.
 *
 *
 *
 * -flush_mod: flush table modification state.
 *  typedef void (ta_flush_mod)(void *ta_buf);
 * OPTIONAL(need_modify), unlocked. (M_WAITOK).
 *
 * Performs flush for the following:
 *   - prepare_mod (modification was not necessary)
 *   - modify (for the old state)
 *
 *
 *
 * -change_gi: monitor table info pointer changes
 * typedef void (ta_change_ti)(void *ta_state, struct table_info *ti);
 * OPTIONAL, locked (UH). (M_NOWAIT).
 *
 * Called on @ti pointer changed. Called immediately after -init
 * to set initial state.
 *
 *
 *
 * -foreach: calls @f for each table entry
 *  typedef void ta_foreach(void *ta_state, struct table_info *ti,
 *      ta_foreach_f *f, void *arg);
 * MANDATORY, locked(UH). (M_NOWAIT).
 *
 * Runs callback with specified argument for each table entry,
 * Typically used for dumping table entries.
 *
 *
 *
 * -dump_tentry: dump table entry in current @tentry format.
 *  typedef int ta_dump_tentry(void *ta_state, struct table_info *ti, void *e,
 *      ipfw_obj_tentry *tent);
 * MANDATORY, locked(UH). (M_NOWAIT). Returns 0 on success.
 *
 * Dumps entry @e to @tent.
 *
 *
 * -print_config: prints custom algoritm options into buffer.
 *  typedef void (ta_print_config)(void *ta_state, struct table_info *ti,
 *      char *buf, size_t bufsize);
 * OPTIONAL. locked(UH). (M_NOWAIT).
 *
 * Prints custom algorithm options in the format suitable to pass
 * back to -init callback.
 *
 *
 *
 * -dump_tinfo: dumps algo-specific info.
 *  typedef void ta_dump_tinfo(void *ta_state, struct table_info *ti,
 *      ipfw_ta_tinfo *tinfo);
 * OPTIONAL. locked(UH). (M_NOWAIT).
 *
 * Dumps options like items size/hash size, etc.
 */

MALLOC_DEFINE(M_IPFW_TBL, "ipfw_tbl", "IpFw tables");

/*
 * Utility structures/functions common to more than one algo
 */

struct mod_item {
	void	*main_ptr;
	size_t	size;
	void	*main_ptr6;
	size_t	size6;
};

static int badd(const void *key, void *item, void *base, size_t nmemb,
    size_t size, int (*compar) (const void *, const void *));
static int bdel(const void *key, void *base, size_t nmemb, size_t size,
    int (*compar) (const void *, const void *));


/*
 * ADDR implementation using radix
 *
 */

/*
 * The radix code expects addr and mask to be array of bytes,
 * with the first byte being the length of the array. rn_inithead
 * is called with the offset in bits of the lookup key within the
 * array. If we use a sockaddr_in as the underlying type,
 * sin_len is conveniently located at offset 0, sin_addr is at
 * offset 4 and normally aligned.
 * But for portability, let's avoid assumption and make the code explicit
 */
#define KEY_LEN(v)	*((uint8_t *)&(v))
/*
 * Do not require radix to compare more than actual IPv4/IPv6 address
 */
#define KEY_LEN_INET	(offsetof(struct sockaddr_in, sin_addr) + sizeof(in_addr_t))
#define KEY_LEN_INET6	(offsetof(struct sa_in6, sin6_addr) + sizeof(struct in6_addr))

#define OFF_LEN_INET	(8 * offsetof(struct sockaddr_in, sin_addr))
#define OFF_LEN_INET6	(8 * offsetof(struct sa_in6, sin6_addr))

struct radix_addr_entry {
	struct radix_node	rn[2];
	struct sockaddr_in	addr;
	uint32_t		value;
	uint8_t			masklen;
};

struct sa_in6 {
	uint8_t			sin6_len;
	uint8_t			sin6_family;
	uint8_t			pad[2];
	struct in6_addr		sin6_addr;
};

struct radix_addr_xentry {
	struct radix_node	rn[2];
	struct sa_in6		addr6;
	uint32_t		value;
	uint8_t			masklen;
};

struct radix_cfg {
	struct radix_node_head	*head4;
	struct radix_node_head	*head6;
	size_t			count4;
	size_t			count6;
};

struct ta_buf_radix
{
	void *ent_ptr;
	struct sockaddr	*addr_ptr;
	struct sockaddr	*mask_ptr;
	union {
		struct {
			struct sockaddr_in sa;
			struct sockaddr_in ma;
		} a4;
		struct {
			struct sa_in6 sa;
			struct sa_in6 ma;
		} a6;
	} addr;
};

static int
ta_lookup_radix(struct table_info *ti, void *key, uint32_t keylen,
    uint32_t *val)
{
	struct radix_node_head *rnh;

	if (keylen == sizeof(in_addr_t)) {
		struct radix_addr_entry *ent;
		struct sockaddr_in sa;
		KEY_LEN(sa) = KEY_LEN_INET;
		sa.sin_addr.s_addr = *((in_addr_t *)key);
		rnh = (struct radix_node_head *)ti->state;
		ent = (struct radix_addr_entry *)(rnh->rnh_matchaddr(&sa, rnh));
		if (ent != NULL) {
			*val = ent->value;
			return (1);
		}
	} else {
		struct radix_addr_xentry *xent;
		struct sa_in6 sa6;
		KEY_LEN(sa6) = KEY_LEN_INET6;
		memcpy(&sa6.sin6_addr, key, sizeof(struct in6_addr));
		rnh = (struct radix_node_head *)ti->xstate;
		xent = (struct radix_addr_xentry *)(rnh->rnh_matchaddr(&sa6, rnh));
		if (xent != NULL) {
			*val = xent->value;
			return (1);
		}
	}

	return (0);
}

/*
 * New table
 */
static int
ta_init_radix(struct ip_fw_chain *ch, void **ta_state, struct table_info *ti,
    char *data, uint8_t tflags)
{
	struct radix_cfg *cfg;

	if (!rn_inithead(&ti->state, OFF_LEN_INET))
		return (ENOMEM);
	if (!rn_inithead(&ti->xstate, OFF_LEN_INET6)) {
		rn_detachhead(&ti->state);
		return (ENOMEM);
	}

	cfg = malloc(sizeof(struct radix_cfg), M_IPFW, M_WAITOK | M_ZERO);

	*ta_state = cfg;
	ti->lookup = ta_lookup_radix;

	return (0);
}

static int
flush_radix_entry(struct radix_node *rn, void *arg)
{
	struct radix_node_head * const rnh = arg;
	struct radix_addr_entry *ent;

	ent = (struct radix_addr_entry *)
	    rnh->rnh_deladdr(rn->rn_key, rn->rn_mask, rnh);
	if (ent != NULL)
		free(ent, M_IPFW_TBL);
	return (0);
}

static void
ta_destroy_radix(void *ta_state, struct table_info *ti)
{
	struct radix_cfg *cfg;
	struct radix_node_head *rnh;

	cfg = (struct radix_cfg *)ta_state;

	rnh = (struct radix_node_head *)(ti->state);
	rnh->rnh_walktree(rnh, flush_radix_entry, rnh);
	rn_detachhead(&ti->state);

	rnh = (struct radix_node_head *)(ti->xstate);
	rnh->rnh_walktree(rnh, flush_radix_entry, rnh);
	rn_detachhead(&ti->xstate);

	free(cfg, M_IPFW);
}

/*
 * Provide algo-specific table info
 */
static void
ta_dump_radix_tinfo(void *ta_state, struct table_info *ti, ipfw_ta_tinfo *tinfo)
{
	struct radix_cfg *cfg;

	cfg = (struct radix_cfg *)ta_state;

	tinfo->flags = IPFW_TATFLAGS_AFDATA | IPFW_TATFLAGS_AFITEM;
	tinfo->taclass4 = IPFW_TACLASS_RADIX;
	tinfo->count4 = cfg->count4;
	tinfo->itemsize4 = sizeof(struct radix_addr_entry);
	tinfo->taclass6 = IPFW_TACLASS_RADIX;
	tinfo->count6 = cfg->count6;
	tinfo->itemsize6 = sizeof(struct radix_addr_xentry);
}

static int
ta_dump_radix_tentry(void *ta_state, struct table_info *ti, void *e,
    ipfw_obj_tentry *tent)
{
	struct radix_addr_entry *n;
	struct radix_addr_xentry *xn;

	n = (struct radix_addr_entry *)e;

	/* Guess IPv4/IPv6 radix by sockaddr family */
	if (n->addr.sin_family == AF_INET) {
		tent->k.addr.s_addr = n->addr.sin_addr.s_addr;
		tent->masklen = n->masklen;
		tent->subtype = AF_INET;
		tent->v.kidx = n->value;
#ifdef INET6
	} else {
		xn = (struct radix_addr_xentry *)e;
		memcpy(&tent->k, &xn->addr6.sin6_addr, sizeof(struct in6_addr));
		tent->masklen = xn->masklen;
		tent->subtype = AF_INET6;
		tent->v.kidx = xn->value;
#endif
	}

	return (0);
}

static int
ta_find_radix_tentry(void *ta_state, struct table_info *ti,
    ipfw_obj_tentry *tent)
{
	struct radix_node_head *rnh;
	void *e;

	e = NULL;
	if (tent->subtype == AF_INET) {
		struct sockaddr_in sa;
		KEY_LEN(sa) = KEY_LEN_INET;
		sa.sin_addr.s_addr = tent->k.addr.s_addr;
		rnh = (struct radix_node_head *)ti->state;
		e = rnh->rnh_matchaddr(&sa, rnh);
	} else {
		struct sa_in6 sa6;
		KEY_LEN(sa6) = KEY_LEN_INET6;
		memcpy(&sa6.sin6_addr, &tent->k.addr6, sizeof(struct in6_addr));
		rnh = (struct radix_node_head *)ti->xstate;
		e = rnh->rnh_matchaddr(&sa6, rnh);
	}

	if (e != NULL) {
		ta_dump_radix_tentry(ta_state, ti, e, tent);
		return (0);
	}

	return (ENOENT);
}

static void
ta_foreach_radix(void *ta_state, struct table_info *ti, ta_foreach_f *f,
    void *arg)
{
	struct radix_node_head *rnh;

	rnh = (struct radix_node_head *)(ti->state);
	rnh->rnh_walktree(rnh, (walktree_f_t *)f, arg);

	rnh = (struct radix_node_head *)(ti->xstate);
	rnh->rnh_walktree(rnh, (walktree_f_t *)f, arg);
}


#ifdef INET6
static inline void
ipv6_writemask(struct in6_addr *addr6, uint8_t mask)
{
	uint32_t *cp;

	for (cp = (uint32_t *)addr6; mask >= 32; mask -= 32)
		*cp++ = 0xFFFFFFFF;
	*cp = htonl(mask ? ~((1 << (32 - mask)) - 1) : 0);
}
#endif

static void
tei_to_sockaddr_ent(struct tentry_info *tei, struct sockaddr *sa,
    struct sockaddr *ma, int *set_mask)
{
	int mlen;
	struct sockaddr_in *addr, *mask;
	struct sa_in6 *addr6, *mask6;
	in_addr_t a4;

	mlen = tei->masklen;

	if (tei->subtype == AF_INET) {
#ifdef INET
		addr = (struct sockaddr_in *)sa;
		mask = (struct sockaddr_in *)ma;
		/* Set 'total' structure length */
		KEY_LEN(*addr) = KEY_LEN_INET;
		KEY_LEN(*mask) = KEY_LEN_INET;
		addr->sin_family = AF_INET;
		mask->sin_addr.s_addr =
		    htonl(mlen ? ~((1 << (32 - mlen)) - 1) : 0);
		a4 = *((in_addr_t *)tei->paddr);
		addr->sin_addr.s_addr = a4 & mask->sin_addr.s_addr;
		if (mlen != 32)
			*set_mask = 1;
		else
			*set_mask = 0;
#endif
#ifdef INET6
	} else if (tei->subtype == AF_INET6) {
		/* IPv6 case */
		addr6 = (struct sa_in6 *)sa;
		mask6 = (struct sa_in6 *)ma;
		/* Set 'total' structure length */
		KEY_LEN(*addr6) = KEY_LEN_INET6;
		KEY_LEN(*mask6) = KEY_LEN_INET6;
		addr6->sin6_family = AF_INET6;
		ipv6_writemask(&mask6->sin6_addr, mlen);
		memcpy(&addr6->sin6_addr, tei->paddr, sizeof(struct in6_addr));
		APPLY_MASK(&addr6->sin6_addr, &mask6->sin6_addr);
		if (mlen != 128)
			*set_mask = 1;
		else
			*set_mask = 0;
	}
#endif
}

static int
ta_prepare_add_radix(struct ip_fw_chain *ch, struct tentry_info *tei,
    void *ta_buf)
{
	struct ta_buf_radix *tb;
	struct radix_addr_entry *ent;
	struct radix_addr_xentry *xent;
	struct sockaddr *addr, *mask;
	int mlen, set_mask;

	tb = (struct ta_buf_radix *)ta_buf;

	mlen = tei->masklen;
	set_mask = 0;

	if (tei->subtype == AF_INET) {
#ifdef INET
		if (mlen > 32)
			return (EINVAL);
		ent = malloc(sizeof(*ent), M_IPFW_TBL, M_WAITOK | M_ZERO);
		ent->masklen = mlen;

		addr = (struct sockaddr *)&ent->addr;
		mask = (struct sockaddr *)&tb->addr.a4.ma;
		tb->ent_ptr = ent;
#endif
#ifdef INET6
	} else if (tei->subtype == AF_INET6) {
		/* IPv6 case */
		if (mlen > 128)
			return (EINVAL);
		xent = malloc(sizeof(*xent), M_IPFW_TBL, M_WAITOK | M_ZERO);
		xent->masklen = mlen;

		addr = (struct sockaddr *)&xent->addr6;
		mask = (struct sockaddr *)&tb->addr.a6.ma;
		tb->ent_ptr = xent;
#endif
	} else {
		/* Unknown CIDR type */
		return (EINVAL);
	}

	tei_to_sockaddr_ent(tei, addr, mask, &set_mask);
	/* Set pointers */
	tb->addr_ptr = addr;
	if (set_mask != 0)
		tb->mask_ptr = mask;

	return (0);
}

static int
ta_add_radix(void *ta_state, struct table_info *ti, struct tentry_info *tei,
    void *ta_buf, uint32_t *pnum)
{
	struct radix_cfg *cfg;
	struct radix_node_head *rnh;
	struct radix_node *rn;
	struct ta_buf_radix *tb;
	uint32_t *old_value, value;

	cfg = (struct radix_cfg *)ta_state;
	tb = (struct ta_buf_radix *)ta_buf;

	/* Save current entry value from @tei */
	if (tei->subtype == AF_INET) {
		rnh = ti->state;
		((struct radix_addr_entry *)tb->ent_ptr)->value = tei->value;
	} else {
		rnh = ti->xstate;
		((struct radix_addr_xentry *)tb->ent_ptr)->value = tei->value;
	}

	/* Search for an entry first */
	rn = rnh->rnh_lookup(tb->addr_ptr, tb->mask_ptr, rnh);
	if (rn != NULL) {
		if ((tei->flags & TEI_FLAGS_UPDATE) == 0)
			return (EEXIST);
		/* Record already exists. Update value if we're asked to */
		if (tei->subtype == AF_INET)
			old_value = &((struct radix_addr_entry *)rn)->value;
		else
			old_value = &((struct radix_addr_xentry *)rn)->value;

		value = *old_value;
		*old_value = tei->value;
		tei->value = value;

		/* Indicate that update has happened instead of addition */
		tei->flags |= TEI_FLAGS_UPDATED;
		*pnum = 0;

		return (0);
	}

	if ((tei->flags & TEI_FLAGS_DONTADD) != 0)
		return (EFBIG);

	rn = rnh->rnh_addaddr(tb->addr_ptr, tb->mask_ptr, rnh, tb->ent_ptr);
	if (rn == NULL) {
		/* Unknown error */
		return (EINVAL);
	}

	if (tei->subtype == AF_INET)
		cfg->count4++;
	else
		cfg->count6++;
	tb->ent_ptr = NULL;
	*pnum = 1;

	return (0);
}

static int
ta_prepare_del_radix(struct ip_fw_chain *ch, struct tentry_info *tei,
    void *ta_buf)
{
	struct ta_buf_radix *tb;
	struct sockaddr *addr, *mask;
	int mlen, set_mask;

	tb = (struct ta_buf_radix *)ta_buf;

	mlen = tei->masklen;
	set_mask = 0;

	if (tei->subtype == AF_INET) {
		if (mlen > 32)
			return (EINVAL);

		addr = (struct sockaddr *)&tb->addr.a4.sa;
		mask = (struct sockaddr *)&tb->addr.a4.ma;
#ifdef INET6
	} else if (tei->subtype == AF_INET6) {
		if (mlen > 128)
			return (EINVAL);

		addr = (struct sockaddr *)&tb->addr.a6.sa;
		mask = (struct sockaddr *)&tb->addr.a6.ma;
#endif
	} else
		return (EINVAL);

	tei_to_sockaddr_ent(tei, addr, mask, &set_mask);
	tb->addr_ptr = addr;
	if (set_mask != 0)
		tb->mask_ptr = mask;

	return (0);
}

static int
ta_del_radix(void *ta_state, struct table_info *ti, struct tentry_info *tei,
    void *ta_buf, uint32_t *pnum)
{
	struct radix_cfg *cfg;
	struct radix_node_head *rnh;
	struct radix_node *rn;
	struct ta_buf_radix *tb;

	cfg = (struct radix_cfg *)ta_state;
	tb = (struct ta_buf_radix *)ta_buf;

	if (tei->subtype == AF_INET)
		rnh = ti->state;
	else
		rnh = ti->xstate;

	rn = rnh->rnh_deladdr(tb->addr_ptr, tb->mask_ptr, rnh);

	if (rn == NULL)
		return (ENOENT);

	/* Save entry value to @tei */
	if (tei->subtype == AF_INET)
		tei->value = ((struct radix_addr_entry *)rn)->value;
	else
		tei->value = ((struct radix_addr_xentry *)rn)->value;

	tb->ent_ptr = rn;

	if (tei->subtype == AF_INET)
		cfg->count4--;
	else
		cfg->count6--;
	*pnum = 1;

	return (0);
}

static void
ta_flush_radix_entry(struct ip_fw_chain *ch, struct tentry_info *tei,
    void *ta_buf)
{
	struct ta_buf_radix *tb;

	tb = (struct ta_buf_radix *)ta_buf;

	if (tb->ent_ptr != NULL)
		free(tb->ent_ptr, M_IPFW_TBL);
}

static int
ta_need_modify_radix(void *ta_state, struct table_info *ti, uint32_t count,
    uint64_t *pflags)
{

	/*
	 * radix does not require additional memory allocations
	 * other than nodes itself. Adding new masks to the tree do
	 * but we don't have any API to call (and we don't known which
	 * sizes do we need).
	 */
	return (0);
}

struct table_algo addr_radix = {
	.name		= "addr:radix",
	.type		= IPFW_TABLE_ADDR,
	.flags		= TA_FLAG_DEFAULT,
	.ta_buf_size	= sizeof(struct ta_buf_radix),
	.init		= ta_init_radix,
	.destroy	= ta_destroy_radix,
	.prepare_add	= ta_prepare_add_radix,
	.prepare_del	= ta_prepare_del_radix,
	.add		= ta_add_radix,
	.del		= ta_del_radix,
	.flush_entry	= ta_flush_radix_entry,
	.foreach	= ta_foreach_radix,
	.dump_tentry	= ta_dump_radix_tentry,
	.find_tentry	= ta_find_radix_tentry,
	.dump_tinfo	= ta_dump_radix_tinfo,
	.need_modify	= ta_need_modify_radix,
};


/*
 * addr:hash cmds
 *
 *
 * ti->data:
 * [inv.mask4][inv.mask6][log2hsize4][log2hsize6]
 * [        8][        8[          8][         8]
 *
 * inv.mask4: 32 - mask
 * inv.mask6:
 * 1) _slow lookup: mask
 * 2) _aligned: (128 - mask) / 8
 * 3) _64: 8
 *
 *
 * pflags:
 * [v4=1/v6=0][hsize]
 * [       32][   32]
 */

struct chashentry;

SLIST_HEAD(chashbhead, chashentry);

struct chash_cfg {
	struct chashbhead *head4;
	struct chashbhead *head6;
	size_t	size4;
	size_t	size6;
	size_t	items4;
	size_t	items6;
	uint8_t	mask4;
	uint8_t	mask6;
};

struct chashentry {
	SLIST_ENTRY(chashentry)	next;
	uint32_t	value;
	uint32_t	type;
	union {
		uint32_t	a4;	/* Host format */
		struct in6_addr	a6;	/* Network format */
	} a;
};

struct ta_buf_chash
{
	void *ent_ptr;
	struct chashentry ent;
};


static __inline uint32_t
hash_ip(uint32_t addr, int hsize)
{

	return (addr % (hsize - 1));
}

static __inline uint32_t
hash_ip6(struct in6_addr *addr6, int hsize)
{
	uint32_t i;

	i = addr6->s6_addr32[0] ^ addr6->s6_addr32[1] ^
	    addr6->s6_addr32[2] ^ addr6->s6_addr32[3];

	return (i % (hsize - 1));
}


static __inline uint16_t
hash_ip64(struct in6_addr *addr6, int hsize)
{
	uint32_t i;

	i = addr6->s6_addr32[0] ^ addr6->s6_addr32[1];

	return (i % (hsize - 1));
}


static __inline uint32_t
hash_ip6_slow(struct in6_addr *addr6, void *key, int mask, int hsize)
{
	struct in6_addr mask6;

	ipv6_writemask(&mask6, mask);
	memcpy(addr6, key, sizeof(struct in6_addr));
	APPLY_MASK(addr6, &mask6);
	return (hash_ip6(addr6, hsize));
}

static __inline uint32_t
hash_ip6_al(struct in6_addr *addr6, void *key, int mask, int hsize)
{
	uint64_t *paddr;

	paddr = (uint64_t *)addr6;
	*paddr = 0;
	*(paddr + 1) = 0;
	memcpy(addr6, key, mask);
	return (hash_ip6(addr6, hsize));
}

static int
ta_lookup_chash_slow(struct table_info *ti, void *key, uint32_t keylen,
    uint32_t *val)
{
	struct chashbhead *head;
	struct chashentry *ent;
	uint16_t hash, hsize;
	uint8_t imask;

	if (keylen == sizeof(in_addr_t)) {
		head = (struct chashbhead *)ti->state;
		imask = ti->data >> 24;
		hsize = 1 << ((ti->data & 0xFFFF) >> 8);
		uint32_t a;
		a = ntohl(*((in_addr_t *)key));
		a = a >> imask;
		hash = hash_ip(a, hsize);
		SLIST_FOREACH(ent, &head[hash], next) {
			if (ent->a.a4 == a) {
				*val = ent->value;
				return (1);
			}
		}
	} else {
		/* IPv6: worst scenario: non-round mask */
		struct in6_addr addr6;
		head = (struct chashbhead *)ti->xstate;
		imask = (ti->data & 0xFF0000) >> 16;
		hsize = 1 << (ti->data & 0xFF);
		hash = hash_ip6_slow(&addr6, key, imask, hsize);
		SLIST_FOREACH(ent, &head[hash], next) {
			if (memcmp(&ent->a.a6, &addr6, 16) == 0) {
				*val = ent->value;
				return (1);
			}
		}
	}

	return (0);
}

static int
ta_lookup_chash_aligned(struct table_info *ti, void *key, uint32_t keylen,
    uint32_t *val)
{
	struct chashbhead *head;
	struct chashentry *ent;
	uint16_t hash, hsize;
	uint8_t imask;

	if (keylen == sizeof(in_addr_t)) {
		head = (struct chashbhead *)ti->state;
		imask = ti->data >> 24;
		hsize = 1 << ((ti->data & 0xFFFF) >> 8);
		uint32_t a;
		a = ntohl(*((in_addr_t *)key));
		a = a >> imask;
		hash = hash_ip(a, hsize);
		SLIST_FOREACH(ent, &head[hash], next) {
			if (ent->a.a4 == a) {
				*val = ent->value;
				return (1);
			}
		}
	} else {
		/* IPv6: aligned to 8bit mask */
		struct in6_addr addr6;
		uint64_t *paddr, *ptmp;
		head = (struct chashbhead *)ti->xstate;
		imask = (ti->data & 0xFF0000) >> 16;
		hsize = 1 << (ti->data & 0xFF);

		hash = hash_ip6_al(&addr6, key, imask, hsize);
		paddr = (uint64_t *)&addr6;
		SLIST_FOREACH(ent, &head[hash], next) {
			ptmp = (uint64_t *)&ent->a.a6;
			if (paddr[0] == ptmp[0] && paddr[1] == ptmp[1]) {
				*val = ent->value;
				return (1);
			}
		}
	}

	return (0);
}

static int
ta_lookup_chash_64(struct table_info *ti, void *key, uint32_t keylen,
    uint32_t *val)
{
	struct chashbhead *head;
	struct chashentry *ent;
	uint16_t hash, hsize;
	uint8_t imask;

	if (keylen == sizeof(in_addr_t)) {
		head = (struct chashbhead *)ti->state;
		imask = ti->data >> 24;
		hsize = 1 << ((ti->data & 0xFFFF) >> 8);
		uint32_t a;
		a = ntohl(*((in_addr_t *)key));
		a = a >> imask;
		hash = hash_ip(a, hsize);
		SLIST_FOREACH(ent, &head[hash], next) {
			if (ent->a.a4 == a) {
				*val = ent->value;
				return (1);
			}
		}
	} else {
		/* IPv6: /64 */
		uint64_t a6, *paddr;
		head = (struct chashbhead *)ti->xstate;
		paddr = (uint64_t *)key;
		hsize = 1 << (ti->data & 0xFF);
		a6 = *paddr;
		hash = hash_ip64((struct in6_addr *)key, hsize);
		SLIST_FOREACH(ent, &head[hash], next) {
			paddr = (uint64_t *)&ent->a.a6;
			if (a6 == *paddr) {
				*val = ent->value;
				return (1);
			}
		}
	}

	return (0);
}

static int
chash_parse_opts(struct chash_cfg *cfg, char *data)
{
	char *pdel, *pend, *s;
	int mask4, mask6;

	mask4 = cfg->mask4;
	mask6 = cfg->mask6;

	if (data == NULL)
		return (0);
	if ((pdel = strchr(data, ' ')) == NULL)
		return (0);
	while (*pdel == ' ')
		pdel++;
	if (strncmp(pdel, "masks=", 6) != 0)
		return (EINVAL);
	if ((s = strchr(pdel, ' ')) != NULL)
		*s++ = '\0';

	pdel += 6;
	/* Need /XX[,/YY] */
	if (*pdel++ != '/')
		return (EINVAL);
	mask4 = strtol(pdel, &pend, 10);
	if (*pend == ',') {
		/* ,/YY */
		pdel = pend + 1;
		if (*pdel++ != '/')
			return (EINVAL);
		mask6 = strtol(pdel, &pend, 10);
		if (*pend != '\0')
			return (EINVAL);
	} else if (*pend != '\0')
		return (EINVAL);

	if (mask4 < 0 || mask4 > 32 || mask6 < 0 || mask6 > 128)
		return (EINVAL);

	cfg->mask4 = mask4;
	cfg->mask6 = mask6;

	return (0);
}

static void
ta_print_chash_config(void *ta_state, struct table_info *ti, char *buf,
    size_t bufsize)
{
	struct chash_cfg *cfg;

	cfg = (struct chash_cfg *)ta_state;

	if (cfg->mask4 != 32 || cfg->mask6 != 128)
		snprintf(buf, bufsize, "%s masks=/%d,/%d", "addr:hash",
		    cfg->mask4, cfg->mask6);
	else
		snprintf(buf, bufsize, "%s", "addr:hash");
}

static int
log2(uint32_t v)
{
	uint32_t r;

	r = 0;
	while (v >>= 1)
		r++;

	return (r);
}

/*
 * New table.
 * We assume 'data' to be either NULL or the following format:
 * 'addr:hash [masks=/32[,/128]]'
 */
static int
ta_init_chash(struct ip_fw_chain *ch, void **ta_state, struct table_info *ti,
    char *data, uint8_t tflags)
{
	int error, i;
	uint32_t hsize;
	struct chash_cfg *cfg;

	cfg = malloc(sizeof(struct chash_cfg), M_IPFW, M_WAITOK | M_ZERO);

	cfg->mask4 = 32;
	cfg->mask6 = 128;

	if ((error = chash_parse_opts(cfg, data)) != 0) {
		free(cfg, M_IPFW);
		return (error);
	}

	cfg->size4 = 128;
	cfg->size6 = 128;

	cfg->head4 = malloc(sizeof(struct chashbhead) * cfg->size4, M_IPFW,
	    M_WAITOK | M_ZERO);
	cfg->head6 = malloc(sizeof(struct chashbhead) * cfg->size6, M_IPFW,
	    M_WAITOK | M_ZERO);
	for (i = 0; i < cfg->size4; i++)
		SLIST_INIT(&cfg->head4[i]);
	for (i = 0; i < cfg->size6; i++)
		SLIST_INIT(&cfg->head6[i]);


	*ta_state = cfg;
	ti->state = cfg->head4;
	ti->xstate = cfg->head6;

	/* Store data depending on v6 mask length */
	hsize = log2(cfg->size4) << 8 | log2(cfg->size6);
	if (cfg->mask6 == 64) {
		ti->data = (32 - cfg->mask4) << 24 | (128 - cfg->mask6) << 16|
		    hsize;
		ti->lookup = ta_lookup_chash_64;
	} else if ((cfg->mask6  % 8) == 0) {
		ti->data = (32 - cfg->mask4) << 24 |
		    cfg->mask6 << 13 | hsize;
		ti->lookup = ta_lookup_chash_aligned;
	} else {
		/* don't do that! */
		ti->data = (32 - cfg->mask4) << 24 |
		    cfg->mask6 << 16 | hsize;
		ti->lookup = ta_lookup_chash_slow;
	}

	return (0);
}

static void
ta_destroy_chash(void *ta_state, struct table_info *ti)
{
	struct chash_cfg *cfg;
	struct chashentry *ent, *ent_next;
	int i;

	cfg = (struct chash_cfg *)ta_state;

	for (i = 0; i < cfg->size4; i++)
		SLIST_FOREACH_SAFE(ent, &cfg->head4[i], next, ent_next)
			free(ent, M_IPFW_TBL);

	for (i = 0; i < cfg->size6; i++)
		SLIST_FOREACH_SAFE(ent, &cfg->head6[i], next, ent_next)
			free(ent, M_IPFW_TBL);

	free(cfg->head4, M_IPFW);
	free(cfg->head6, M_IPFW);

	free(cfg, M_IPFW);
}

static void
ta_dump_chash_tinfo(void *ta_state, struct table_info *ti, ipfw_ta_tinfo *tinfo)
{
	struct chash_cfg *cfg;

	cfg = (struct chash_cfg *)ta_state;

	tinfo->flags = IPFW_TATFLAGS_AFDATA | IPFW_TATFLAGS_AFITEM;
	tinfo->taclass4 = IPFW_TACLASS_HASH;
	tinfo->size4 = cfg->size4;
	tinfo->count4 = cfg->items4;
	tinfo->itemsize4 = sizeof(struct chashentry);
	tinfo->taclass6 = IPFW_TACLASS_HASH;
	tinfo->size6 = cfg->size6;
	tinfo->count6 = cfg->items6;
	tinfo->itemsize6 = sizeof(struct chashentry);
}

static int
ta_dump_chash_tentry(void *ta_state, struct table_info *ti, void *e,
    ipfw_obj_tentry *tent)
{
	struct chash_cfg *cfg;
	struct chashentry *ent;

	cfg = (struct chash_cfg *)ta_state;
	ent = (struct chashentry *)e;

	if (ent->type == AF_INET) {
		tent->k.addr.s_addr = htonl(ent->a.a4 << (32 - cfg->mask4));
		tent->masklen = cfg->mask4;
		tent->subtype = AF_INET;
		tent->v.kidx = ent->value;
#ifdef INET6
	} else {
		memcpy(&tent->k, &ent->a.a6, sizeof(struct in6_addr));
		tent->masklen = cfg->mask6;
		tent->subtype = AF_INET6;
		tent->v.kidx = ent->value;
#endif
	}

	return (0);
}

static uint32_t
hash_ent(struct chashentry *ent, int af, int mlen, uint32_t size)
{
	uint32_t hash;

	if (af == AF_INET) {
		hash = hash_ip(ent->a.a4, size);
	} else {
		if (mlen == 64)
			hash = hash_ip64(&ent->a.a6, size);
		else
			hash = hash_ip6(&ent->a.a6, size);
	}

	return (hash);
}

static int
tei_to_chash_ent(struct tentry_info *tei, struct chashentry *ent)
{
	struct in6_addr mask6;
	int mlen;


	mlen = tei->masklen;

	if (tei->subtype == AF_INET) {
#ifdef INET
		if (mlen > 32)
			return (EINVAL);
		ent->type = AF_INET;

		/* Calculate masked address */
		ent->a.a4 = ntohl(*((in_addr_t *)tei->paddr)) >> (32 - mlen);
#endif
#ifdef INET6
	} else if (tei->subtype == AF_INET6) {
		/* IPv6 case */
		if (mlen > 128)
			return (EINVAL);
		ent->type = AF_INET6;

		ipv6_writemask(&mask6, mlen);
		memcpy(&ent->a.a6, tei->paddr, sizeof(struct in6_addr));
		APPLY_MASK(&ent->a.a6, &mask6);
#endif
	} else {
		/* Unknown CIDR type */
		return (EINVAL);
	}

	return (0);
}

static int
ta_find_chash_tentry(void *ta_state, struct table_info *ti,
    ipfw_obj_tentry *tent)
{
	struct chash_cfg *cfg;
	struct chashbhead *head;
	struct chashentry ent, *tmp;
	struct tentry_info tei;
	int error;
	uint32_t hash;

	cfg = (struct chash_cfg *)ta_state;

	memset(&ent, 0, sizeof(ent));
	memset(&tei, 0, sizeof(tei));

	if (tent->subtype == AF_INET) {
		tei.paddr = &tent->k.addr;
		tei.masklen = cfg->mask4;
		tei.subtype = AF_INET;

		if ((error = tei_to_chash_ent(&tei, &ent)) != 0)
			return (error);

		head = cfg->head4;
		hash = hash_ent(&ent, AF_INET, cfg->mask4, cfg->size4);
		/* Check for existence */
		SLIST_FOREACH(tmp, &head[hash], next) {
			if (tmp->a.a4 != ent.a.a4)
				continue;

			ta_dump_chash_tentry(ta_state, ti, tmp, tent);
			return (0);
		}
	} else {
		tei.paddr = &tent->k.addr6;
		tei.masklen = cfg->mask6;
		tei.subtype = AF_INET6;

		if ((error = tei_to_chash_ent(&tei, &ent)) != 0)
			return (error);

		head = cfg->head6;
		hash = hash_ent(&ent, AF_INET6, cfg->mask6, cfg->size6);
		/* Check for existence */
		SLIST_FOREACH(tmp, &head[hash], next) {
			if (memcmp(&tmp->a.a6, &ent.a.a6, 16) != 0)
				continue;
			ta_dump_chash_tentry(ta_state, ti, tmp, tent);
			return (0);
		}
	}

	return (ENOENT);
}

static void
ta_foreach_chash(void *ta_state, struct table_info *ti, ta_foreach_f *f,
    void *arg)
{
	struct chash_cfg *cfg;
	struct chashentry *ent, *ent_next;
	int i;

	cfg = (struct chash_cfg *)ta_state;

	for (i = 0; i < cfg->size4; i++)
		SLIST_FOREACH_SAFE(ent, &cfg->head4[i], next, ent_next)
			f(ent, arg);

	for (i = 0; i < cfg->size6; i++)
		SLIST_FOREACH_SAFE(ent, &cfg->head6[i], next, ent_next)
			f(ent, arg);
}

static int
ta_prepare_add_chash(struct ip_fw_chain *ch, struct tentry_info *tei,
    void *ta_buf)
{
	struct ta_buf_chash *tb;
	struct chashentry *ent;
	int error;

	tb = (struct ta_buf_chash *)ta_buf;

	ent = malloc(sizeof(*ent), M_IPFW_TBL, M_WAITOK | M_ZERO);

	error = tei_to_chash_ent(tei, ent);
	if (error != 0) {
		free(ent, M_IPFW_TBL);
		return (error);
	}
	tb->ent_ptr = ent;

	return (0);
}

static int
ta_add_chash(void *ta_state, struct table_info *ti, struct tentry_info *tei,
    void *ta_buf, uint32_t *pnum)
{
	struct chash_cfg *cfg;
	struct chashbhead *head;
	struct chashentry *ent, *tmp;
	struct ta_buf_chash *tb;
	int exists;
	uint32_t hash, value;

	cfg = (struct chash_cfg *)ta_state;
	tb = (struct ta_buf_chash *)ta_buf;
	ent = (struct chashentry *)tb->ent_ptr;
	hash = 0;
	exists = 0;

	/* Read current value from @tei */
	ent->value = tei->value;

	/* Read cuurrent value */
	if (tei->subtype == AF_INET) {
		if (tei->masklen != cfg->mask4)
			return (EINVAL);
		head = cfg->head4;
		hash = hash_ent(ent, AF_INET, cfg->mask4, cfg->size4);

		/* Check for existence */
		SLIST_FOREACH(tmp, &head[hash], next) {
			if (tmp->a.a4 == ent->a.a4) {
				exists = 1;
				break;
			}
		}
	} else {
		if (tei->masklen != cfg->mask6)
			return (EINVAL);
		head = cfg->head6;
		hash = hash_ent(ent, AF_INET6, cfg->mask6, cfg->size6);
		/* Check for existence */
		SLIST_FOREACH(tmp, &head[hash], next) {
			if (memcmp(&tmp->a.a6, &ent->a.a6, 16) == 0) {
				exists = 1;
				break;
			}
		}
	}

	if (exists == 1) {
		if ((tei->flags & TEI_FLAGS_UPDATE) == 0)
			return (EEXIST);
		/* Record already exists. Update value if we're asked to */
		value = tmp->value;
		tmp->value = tei->value;
		tei->value = value;
		/* Indicate that update has happened instead of addition */
		tei->flags |= TEI_FLAGS_UPDATED;
		*pnum = 0;
	} else {
		if ((tei->flags & TEI_FLAGS_DONTADD) != 0)
			return (EFBIG);
		SLIST_INSERT_HEAD(&head[hash], ent, next);
		tb->ent_ptr = NULL;
		*pnum = 1;

		/* Update counters */
		if (tei->subtype == AF_INET)
			cfg->items4++;
		else
			cfg->items6++;
	}

	return (0);
}

static int
ta_prepare_del_chash(struct ip_fw_chain *ch, struct tentry_info *tei,
    void *ta_buf)
{
	struct ta_buf_chash *tb;

	tb = (struct ta_buf_chash *)ta_buf;

	return (tei_to_chash_ent(tei, &tb->ent));
}

static int
ta_del_chash(void *ta_state, struct table_info *ti, struct tentry_info *tei,
    void *ta_buf, uint32_t *pnum)
{
	struct chash_cfg *cfg;
	struct chashbhead *head;
	struct chashentry *tmp, *tmp_next, *ent;
	struct ta_buf_chash *tb;
	uint32_t hash;

	cfg = (struct chash_cfg *)ta_state;
	tb = (struct ta_buf_chash *)ta_buf;
	ent = &tb->ent;

	if (tei->subtype == AF_INET) {
		if (tei->masklen != cfg->mask4)
			return (EINVAL);
		head = cfg->head4;
		hash = hash_ent(ent, AF_INET, cfg->mask4, cfg->size4);

		SLIST_FOREACH_SAFE(tmp, &head[hash], next, tmp_next) {
			if (tmp->a.a4 != ent->a.a4)
				continue;

			SLIST_REMOVE(&head[hash], tmp, chashentry, next);
			cfg->items4--;
			tb->ent_ptr = tmp;
			tei->value = tmp->value;
			*pnum = 1;
			return (0);
		}
	} else {
		if (tei->masklen != cfg->mask6)
			return (EINVAL);
		head = cfg->head6;
		hash = hash_ent(ent, AF_INET6, cfg->mask6, cfg->size6);
		SLIST_FOREACH_SAFE(tmp, &head[hash], next, tmp_next) {
			if (memcmp(&tmp->a.a6, &ent->a.a6, 16) != 0)
				continue;

			SLIST_REMOVE(&head[hash], tmp, chashentry, next);
			cfg->items6--;
			tb->ent_ptr = tmp;
			tei->value = tmp->value;
			*pnum = 1;
			return (0);
		}
	}

	return (ENOENT);
}

static void
ta_flush_chash_entry(struct ip_fw_chain *ch, struct tentry_info *tei,
    void *ta_buf)
{
	struct ta_buf_chash *tb;

	tb = (struct ta_buf_chash *)ta_buf;

	if (tb->ent_ptr != NULL)
		free(tb->ent_ptr, M_IPFW_TBL);
}

/*
 * Hash growing callbacks.
 */

static int
ta_need_modify_chash(void *ta_state, struct table_info *ti, uint32_t count,
    uint64_t *pflags)
{
	struct chash_cfg *cfg;
	uint64_t data;

	/*
	 * Since we don't know exact number of IPv4/IPv6 records in @count,
	 * ignore non-zero @count value at all. Check current hash sizes
	 * and return appropriate data.
	 */

	cfg = (struct chash_cfg *)ta_state;

	data = 0;
	if (cfg->items4 > cfg->size4 && cfg->size4 < 65536)
		data |= (cfg->size4 * 2) << 16;
	if (cfg->items6 > cfg->size6 && cfg->size6 < 65536)
		data |= cfg->size6 * 2;

	if (data != 0) {
		*pflags = data;
		return (1);
	}

	return (0);
}

/*
 * Allocate new, larger chash.
 */
static int
ta_prepare_mod_chash(void *ta_buf, uint64_t *pflags)
{
	struct mod_item *mi;
	struct chashbhead *head;
	int i;

	mi = (struct mod_item *)ta_buf;

	memset(mi, 0, sizeof(struct mod_item));
	mi->size = (*pflags >> 16) & 0xFFFF;
	mi->size6 = *pflags & 0xFFFF;
	if (mi->size > 0) {
		head = malloc(sizeof(struct chashbhead) * mi->size,
		    M_IPFW, M_WAITOK | M_ZERO);
		for (i = 0; i < mi->size; i++)
			SLIST_INIT(&head[i]);
		mi->main_ptr = head;
	}

	if (mi->size6 > 0) {
		head = malloc(sizeof(struct chashbhead) * mi->size6,
		    M_IPFW, M_WAITOK | M_ZERO);
		for (i = 0; i < mi->size6; i++)
			SLIST_INIT(&head[i]);
		mi->main_ptr6 = head;
	}

	return (0);
}

/*
 * Copy data from old runtime array to new one.
 */
static int
ta_fill_mod_chash(void *ta_state, struct table_info *ti, void *ta_buf,
    uint64_t *pflags)
{

	/* In is not possible to do rehash if we're not holidng WLOCK. */
	return (0);
}

/*
 * Switch old & new arrays.
 */
static void
ta_modify_chash(void *ta_state, struct table_info *ti, void *ta_buf,
    uint64_t pflags)
{
	struct mod_item *mi;
	struct chash_cfg *cfg;
	struct chashbhead *old_head, *new_head;
	struct chashentry *ent, *ent_next;
	int af, i, mlen;
	uint32_t nhash;
	size_t old_size, new_size;

	mi = (struct mod_item *)ta_buf;
	cfg = (struct chash_cfg *)ta_state;

	/* Check which hash we need to grow and do we still need that */
	if (mi->size > 0 && cfg->size4 < mi->size) {
		new_head = (struct chashbhead *)mi->main_ptr;
		new_size = mi->size;
		old_size = cfg->size4;
		old_head = ti->state;
		mlen = cfg->mask4;
		af = AF_INET;

		for (i = 0; i < old_size; i++) {
			SLIST_FOREACH_SAFE(ent, &old_head[i], next, ent_next) {
				nhash = hash_ent(ent, af, mlen, new_size);
				SLIST_INSERT_HEAD(&new_head[nhash], ent, next);
			}
		}

		ti->state = new_head;
		cfg->head4 = new_head;
		cfg->size4 = mi->size;
		mi->main_ptr = old_head;
	}

	if (mi->size6 > 0 && cfg->size6 < mi->size6) {
		new_head = (struct chashbhead *)mi->main_ptr6;
		new_size = mi->size6;
		old_size = cfg->size6;
		old_head = ti->xstate;
		mlen = cfg->mask6;
		af = AF_INET6;

		for (i = 0; i < old_size; i++) {
			SLIST_FOREACH_SAFE(ent, &old_head[i], next, ent_next) {
				nhash = hash_ent(ent, af, mlen, new_size);
				SLIST_INSERT_HEAD(&new_head[nhash], ent, next);
			}
		}

		ti->xstate = new_head;
		cfg->head6 = new_head;
		cfg->size6 = mi->size6;
		mi->main_ptr6 = old_head;
	}

	/* Update lower 32 bits with new values */
	ti->data &= 0xFFFFFFFF00000000;
	ti->data |= log2(cfg->size4) << 8 | log2(cfg->size6);
}

/*
 * Free unneded array.
 */
static void
ta_flush_mod_chash(void *ta_buf)
{
	struct mod_item *mi;

	mi = (struct mod_item *)ta_buf;
	if (mi->main_ptr != NULL)
		free(mi->main_ptr, M_IPFW);
	if (mi->main_ptr6 != NULL)
		free(mi->main_ptr6, M_IPFW);
}

struct table_algo addr_hash = {
	.name		= "addr:hash",
	.type		= IPFW_TABLE_ADDR,
	.ta_buf_size	= sizeof(struct ta_buf_chash),
	.init		= ta_init_chash,
	.destroy	= ta_destroy_chash,
	.prepare_add	= ta_prepare_add_chash,
	.prepare_del	= ta_prepare_del_chash,
	.add		= ta_add_chash,
	.del		= ta_del_chash,
	.flush_entry	= ta_flush_chash_entry,
	.foreach	= ta_foreach_chash,
	.dump_tentry	= ta_dump_chash_tentry,
	.find_tentry	= ta_find_chash_tentry,
	.print_config	= ta_print_chash_config,
	.dump_tinfo	= ta_dump_chash_tinfo,
	.need_modify	= ta_need_modify_chash,
	.prepare_mod	= ta_prepare_mod_chash,
	.fill_mod	= ta_fill_mod_chash,
	.modify		= ta_modify_chash,
	.flush_mod	= ta_flush_mod_chash,
};


/*
 * Iface table cmds.
 *
 * Implementation:
 *
 * Runtime part:
 * - sorted array of "struct ifidx" pointed by ti->state.
 *   Array is allocated with rounding up to IFIDX_CHUNK. Only existing
 *   interfaces are stored in array, however its allocated size is
 *   sufficient to hold all table records if needed.
 * - current array size is stored in ti->data
 *
 * Table data:
 * - "struct iftable_cfg" is allocated to store table state (ta_state).
 * - All table records are stored inside namedobj instance.
 *
 */

struct ifidx {
	uint16_t	kidx;
	uint16_t	spare;
	uint32_t	value;
};
#define	DEFAULT_IFIDX_SIZE	64

struct iftable_cfg;

struct ifentry {
	struct named_object	no;
	struct ipfw_ifc		ic;
	struct iftable_cfg	*icfg;
	uint32_t		value;
	int			linked;
};

struct iftable_cfg {
	struct namedobj_instance	*ii;
	struct ip_fw_chain	*ch;
	struct table_info	*ti;
	void	*main_ptr;
	size_t	size;	/* Number of items allocated in array */
	size_t	count;	/* Number of all items */
	size_t	used;	/* Number of items _active_ now */
};

struct ta_buf_ifidx
{
	struct ifentry *ife;
	uint32_t value;
};

int compare_ifidx(const void *k, const void *v);
static void if_notifier(struct ip_fw_chain *ch, void *cbdata, uint16_t ifindex);

int
compare_ifidx(const void *k, const void *v)
{
	const struct ifidx *ifidx;
	uint16_t key;

	key = *((const uint16_t *)k);
	ifidx = (const struct ifidx *)v;

	if (key < ifidx->kidx)
		return (-1);
	else if (key > ifidx->kidx)
		return (1);

	return (0);
}

/*
 * Adds item @item with key @key into ascending-sorted array @base.
 * Assumes @base has enough additional storage.
 *
 * Returns 1 on success, 0 on duplicate key.
 */
static int
badd(const void *key, void *item, void *base, size_t nmemb,
    size_t size, int (*compar) (const void *, const void *))
{
	int min, max, mid, shift, res;
	caddr_t paddr;

	if (nmemb == 0) {
		memcpy(base, item, size);
		return (1);
	}

	/* Binary search */
	min = 0;
	max = nmemb - 1;
	mid = 0;
	while (min <= max) {
		mid = (min + max) / 2;
		res = compar(key, (const void *)((caddr_t)base + mid * size));
		if (res == 0)
			return (0);

		if (res > 0)
			min = mid + 1;
		else
			max = mid - 1;
	}

	/* Item not found. */
	res = compar(key, (const void *)((caddr_t)base + mid * size));
	if (res > 0)
		shift = mid + 1;
	else
		shift = mid;

	paddr = (caddr_t)base + shift * size;
	if (nmemb > shift)
		memmove(paddr + size, paddr, (nmemb - shift) * size);

	memcpy(paddr, item, size);

	return (1);
}

/*
 * Deletes item with key @key from ascending-sorted array @base.
 *
 * Returns 1 on success, 0 for non-existent key.
 */
static int
bdel(const void *key, void *base, size_t nmemb, size_t size,
    int (*compar) (const void *, const void *))
{
	caddr_t item;
	size_t sz;

	item = (caddr_t)bsearch(key, base, nmemb, size, compar);

	if (item == NULL)
		return (0);

	sz = (caddr_t)base + nmemb * size - item;

	if (sz > 0)
		memmove(item, item + size, sz);

	return (1);
}

static struct ifidx *
ifidx_find(struct table_info *ti, void *key)
{
	struct ifidx *ifi;

	ifi = bsearch(key, ti->state, ti->data, sizeof(struct ifidx),
	    compare_ifidx);

	return (ifi);
}

static int
ta_lookup_ifidx(struct table_info *ti, void *key, uint32_t keylen,
    uint32_t *val)
{
	struct ifidx *ifi;

	ifi = ifidx_find(ti, key);

	if (ifi != NULL) {
		*val = ifi->value;
		return (1);
	}

	return (0);
}

static int
ta_init_ifidx(struct ip_fw_chain *ch, void **ta_state, struct table_info *ti,
    char *data, uint8_t tflags)
{
	struct iftable_cfg *icfg;

	icfg = malloc(sizeof(struct iftable_cfg), M_IPFW, M_WAITOK | M_ZERO);

	icfg->ii = ipfw_objhash_create(DEFAULT_IFIDX_SIZE);
	icfg->size = DEFAULT_IFIDX_SIZE;
	icfg->main_ptr = malloc(sizeof(struct ifidx) * icfg->size, M_IPFW,
	    M_WAITOK | M_ZERO);
	icfg->ch = ch;

	*ta_state = icfg;
	ti->state = icfg->main_ptr;
	ti->lookup = ta_lookup_ifidx;

	return (0);
}

/*
 * Handle tableinfo @ti pointer change (on table array resize).
 */
static void
ta_change_ti_ifidx(void *ta_state, struct table_info *ti)
{
	struct iftable_cfg *icfg;

	icfg = (struct iftable_cfg *)ta_state;
	icfg->ti = ti;
}

static void
destroy_ifidx_locked(struct namedobj_instance *ii, struct named_object *no,
    void *arg)
{
	struct ifentry *ife;
	struct ip_fw_chain *ch;

	ch = (struct ip_fw_chain *)arg;
	ife = (struct ifentry *)no;

	ipfw_iface_del_notify(ch, &ife->ic);
	free(ife, M_IPFW_TBL);
}


/*
 * Destroys table @ti
 */
static void
ta_destroy_ifidx(void *ta_state, struct table_info *ti)
{
	struct iftable_cfg *icfg;
	struct ip_fw_chain *ch;

	icfg = (struct iftable_cfg *)ta_state;
	ch = icfg->ch;

	if (icfg->main_ptr != NULL)
		free(icfg->main_ptr, M_IPFW);

	ipfw_objhash_foreach(icfg->ii, destroy_ifidx_locked, ch);

	ipfw_objhash_destroy(icfg->ii);

	free(icfg, M_IPFW);
}

/*
 * Provide algo-specific table info
 */
static void
ta_dump_ifidx_tinfo(void *ta_state, struct table_info *ti, ipfw_ta_tinfo *tinfo)
{
	struct iftable_cfg *cfg;

	cfg = (struct iftable_cfg *)ta_state;

	tinfo->taclass4 = IPFW_TACLASS_ARRAY;
	tinfo->size4 = cfg->size;
	tinfo->count4 = cfg->used;
	tinfo->itemsize4 = sizeof(struct ifidx);
}

/*
 * Prepare state to add to the table:
 * allocate ifentry and reference needed interface.
 */
static int
ta_prepare_add_ifidx(struct ip_fw_chain *ch, struct tentry_info *tei,
    void *ta_buf)
{
	struct ta_buf_ifidx *tb;
	char *ifname;
	struct ifentry *ife;

	tb = (struct ta_buf_ifidx *)ta_buf;

	/* Check if string is terminated */
	ifname = (char *)tei->paddr;
	if (strnlen(ifname, IF_NAMESIZE) == IF_NAMESIZE)
		return (EINVAL);

	ife = malloc(sizeof(struct ifentry), M_IPFW_TBL, M_WAITOK | M_ZERO);
	ife->ic.cb = if_notifier;
	ife->ic.cbdata = ife;

	if (ipfw_iface_ref(ch, ifname, &ife->ic) != 0) {
		free(ife, M_IPFW_TBL);
		return (EINVAL);
	}

	/* Use ipfw_iface 'ifname' field as stable storage */
	ife->no.name = ife->ic.iface->ifname;

	tb->ife = ife;

	return (0);
}

static int
ta_add_ifidx(void *ta_state, struct table_info *ti, struct tentry_info *tei,
    void *ta_buf, uint32_t *pnum)
{
	struct iftable_cfg *icfg;
	struct ifentry *ife, *tmp;
	struct ta_buf_ifidx *tb;
	struct ipfw_iface *iif;
	struct ifidx *ifi;
	char *ifname;
	uint32_t value;

	tb = (struct ta_buf_ifidx *)ta_buf;
	ifname = (char *)tei->paddr;
	icfg = (struct iftable_cfg *)ta_state;
	ife = tb->ife;

	ife->icfg = icfg;
	ife->value = tei->value;

	tmp = (struct ifentry *)ipfw_objhash_lookup_name(icfg->ii, 0, ifname);

	if (tmp != NULL) {
		if ((tei->flags & TEI_FLAGS_UPDATE) == 0)
			return (EEXIST);

		/* Exchange values in @tmp and @tei */
		value = tmp->value;
		tmp->value = tei->value;
		tei->value = value;

		iif = tmp->ic.iface;
		if (iif->resolved != 0) {
			/* We have to update runtime value, too */
			ifi = ifidx_find(ti, &iif->ifindex);
			ifi->value = ife->value;
		}

		/* Indicate that update has happened instead of addition */
		tei->flags |= TEI_FLAGS_UPDATED;
		*pnum = 0;
		return (0);
	}

	if ((tei->flags & TEI_FLAGS_DONTADD) != 0)
		return (EFBIG);

	/* Link to internal list */
	ipfw_objhash_add(icfg->ii, &ife->no);

	/* Link notifier (possible running its callback) */
	ipfw_iface_add_notify(icfg->ch, &ife->ic);
	icfg->count++;

	tb->ife = NULL;
	*pnum = 1;

	return (0);
}

/*
 * Prepare to delete key from table.
 * Do basic interface name checks.
 */
static int
ta_prepare_del_ifidx(struct ip_fw_chain *ch, struct tentry_info *tei,
    void *ta_buf)
{
	struct ta_buf_ifidx *tb;
	char *ifname;

	tb = (struct ta_buf_ifidx *)ta_buf;

	/* Check if string is terminated */
	ifname = (char *)tei->paddr;
	if (strnlen(ifname, IF_NAMESIZE) == IF_NAMESIZE)
		return (EINVAL);

	return (0);
}

/*
 * Remove key from both configuration list and
 * runtime array. Removed interface notification.
 */
static int
ta_del_ifidx(void *ta_state, struct table_info *ti, struct tentry_info *tei,
    void *ta_buf, uint32_t *pnum)
{
	struct iftable_cfg *icfg;
	struct ifentry *ife;
	struct ta_buf_ifidx *tb;
	char *ifname;
	uint16_t ifindex;
	int res;

	tb = (struct ta_buf_ifidx *)ta_buf;
	ifname = (char *)tei->paddr;
	icfg = (struct iftable_cfg *)ta_state;
	ife = tb->ife;

	ife = (struct ifentry *)ipfw_objhash_lookup_name(icfg->ii, 0, ifname);

	if (ife == NULL)
		return (ENOENT);

	if (ife->linked != 0) {
		/* We have to remove item from runtime */
		ifindex = ife->ic.iface->ifindex;

		res = bdel(&ifindex, icfg->main_ptr, icfg->used,
		    sizeof(struct ifidx), compare_ifidx);

		KASSERT(res == 1, ("index %d does not exist", ifindex));
		icfg->used--;
		ti->data = icfg->used;
		ife->linked = 0;
	}

	/* Unlink from local list */
	ipfw_objhash_del(icfg->ii, &ife->no);
	/* Unlink notifier */
	ipfw_iface_del_notify(icfg->ch, &ife->ic);

	icfg->count--;
	tei->value = ife->value;

	tb->ife = ife;
	*pnum = 1;

	return (0);
}

/*
 * Flush deleted entry.
 * Drops interface reference and frees entry.
 */
static void
ta_flush_ifidx_entry(struct ip_fw_chain *ch, struct tentry_info *tei,
    void *ta_buf)
{
	struct ta_buf_ifidx *tb;

	tb = (struct ta_buf_ifidx *)ta_buf;

	if (tb->ife != NULL) {
		/* Unlink first */
		ipfw_iface_unref(ch, &tb->ife->ic);
		free(tb->ife, M_IPFW_TBL);
	}
}


/*
 * Handle interface announce/withdrawal for particular table.
 * Every real runtime array modification happens here.
 */
static void
if_notifier(struct ip_fw_chain *ch, void *cbdata, uint16_t ifindex)
{
	struct ifentry *ife;
	struct ifidx ifi;
	struct iftable_cfg *icfg;
	struct table_info *ti;
	int res;

	ife = (struct ifentry *)cbdata;
	icfg = ife->icfg;
	ti = icfg->ti;

	KASSERT(ti != NULL, ("ti=NULL, check change_ti handler"));

	if (ife->linked == 0 && ifindex != 0) {
		/* Interface announce */
		ifi.kidx = ifindex;
		ifi.spare = 0;
		ifi.value = ife->value;
		res = badd(&ifindex, &ifi, icfg->main_ptr, icfg->used,
		    sizeof(struct ifidx), compare_ifidx);
		KASSERT(res == 1, ("index %d already exists", ifindex));
		icfg->used++;
		ti->data = icfg->used;
		ife->linked = 1;
	} else if (ife->linked != 0 && ifindex == 0) {
		/* Interface withdrawal */
		ifindex = ife->ic.iface->ifindex;

		res = bdel(&ifindex, icfg->main_ptr, icfg->used,
		    sizeof(struct ifidx), compare_ifidx);

		KASSERT(res == 1, ("index %d does not exist", ifindex));
		icfg->used--;
		ti->data = icfg->used;
		ife->linked = 0;
	}
}


/*
 * Table growing callbacks.
 */

static int
ta_need_modify_ifidx(void *ta_state, struct table_info *ti, uint32_t count,
    uint64_t *pflags)
{
	struct iftable_cfg *cfg;
	uint32_t size;

	cfg = (struct iftable_cfg *)ta_state;

	size = cfg->size;
	while (size < cfg->count + count)
		size *= 2;

	if (size != cfg->size) {
		*pflags = size;
		return (1);
	}

	return (0);
}

/*
 * Allocate ned, larger runtime ifidx array.
 */
static int
ta_prepare_mod_ifidx(void *ta_buf, uint64_t *pflags)
{
	struct mod_item *mi;

	mi = (struct mod_item *)ta_buf;

	memset(mi, 0, sizeof(struct mod_item));
	mi->size = *pflags;
	mi->main_ptr = malloc(sizeof(struct ifidx) * mi->size, M_IPFW,
	    M_WAITOK | M_ZERO);

	return (0);
}

/*
 * Copy data from old runtime array to new one.
 */
static int
ta_fill_mod_ifidx(void *ta_state, struct table_info *ti, void *ta_buf,
    uint64_t *pflags)
{
	struct mod_item *mi;
	struct iftable_cfg *icfg;

	mi = (struct mod_item *)ta_buf;
	icfg = (struct iftable_cfg *)ta_state;

	/* Check if we still need to grow array */
	if (icfg->size >= mi->size) {
		*pflags = 0;
		return (0);
	}

	memcpy(mi->main_ptr, icfg->main_ptr, icfg->used * sizeof(struct ifidx));

	return (0);
}

/*
 * Switch old & new arrays.
 */
static void
ta_modify_ifidx(void *ta_state, struct table_info *ti, void *ta_buf,
    uint64_t pflags)
{
	struct mod_item *mi;
	struct iftable_cfg *icfg;
	void *old_ptr;

	mi = (struct mod_item *)ta_buf;
	icfg = (struct iftable_cfg *)ta_state;

	old_ptr = icfg->main_ptr;
	icfg->main_ptr = mi->main_ptr;
	icfg->size = mi->size;
	ti->state = icfg->main_ptr;

	mi->main_ptr = old_ptr;
}

/*
 * Free unneded array.
 */
static void
ta_flush_mod_ifidx(void *ta_buf)
{
	struct mod_item *mi;

	mi = (struct mod_item *)ta_buf;
	if (mi->main_ptr != NULL)
		free(mi->main_ptr, M_IPFW);
}

static int
ta_dump_ifidx_tentry(void *ta_state, struct table_info *ti, void *e,
    ipfw_obj_tentry *tent)
{
	struct ifentry *ife;

	ife = (struct ifentry *)e;

	tent->masklen = 8 * IF_NAMESIZE;
	memcpy(&tent->k, ife->no.name, IF_NAMESIZE);
	tent->v.kidx = ife->value;

	return (0);
}

static int
ta_find_ifidx_tentry(void *ta_state, struct table_info *ti,
    ipfw_obj_tentry *tent)
{
	struct iftable_cfg *icfg;
	struct ifentry *ife;
	char *ifname;

	icfg = (struct iftable_cfg *)ta_state;
	ifname = tent->k.iface;

	if (strnlen(ifname, IF_NAMESIZE) == IF_NAMESIZE)
		return (EINVAL);

	ife = (struct ifentry *)ipfw_objhash_lookup_name(icfg->ii, 0, ifname);

	if (ife != NULL) {
		ta_dump_ifidx_tentry(ta_state, ti, ife, tent);
		return (0);
	}

	return (ENOENT);
}

struct wa_ifidx {
	ta_foreach_f	*f;
	void		*arg;
};

static void
foreach_ifidx(struct namedobj_instance *ii, struct named_object *no,
    void *arg)
{
	struct ifentry *ife;
	struct wa_ifidx *wa;

	ife = (struct ifentry *)no;
	wa = (struct wa_ifidx *)arg;

	wa->f(ife, wa->arg);
}

static void
ta_foreach_ifidx(void *ta_state, struct table_info *ti, ta_foreach_f *f,
    void *arg)
{
	struct iftable_cfg *icfg;
	struct wa_ifidx wa;

	icfg = (struct iftable_cfg *)ta_state;

	wa.f = f;
	wa.arg = arg;

	ipfw_objhash_foreach(icfg->ii, foreach_ifidx, &wa);
}

struct table_algo iface_idx = {
	.name		= "iface:array",
	.type		= IPFW_TABLE_INTERFACE,
	.flags		= TA_FLAG_DEFAULT,
	.ta_buf_size	= sizeof(struct ta_buf_ifidx),
	.init		= ta_init_ifidx,
	.destroy	= ta_destroy_ifidx,
	.prepare_add	= ta_prepare_add_ifidx,
	.prepare_del	= ta_prepare_del_ifidx,
	.add		= ta_add_ifidx,
	.del		= ta_del_ifidx,
	.flush_entry	= ta_flush_ifidx_entry,
	.foreach	= ta_foreach_ifidx,
	.dump_tentry	= ta_dump_ifidx_tentry,
	.find_tentry	= ta_find_ifidx_tentry,
	.dump_tinfo	= ta_dump_ifidx_tinfo,
	.need_modify	= ta_need_modify_ifidx,
	.prepare_mod	= ta_prepare_mod_ifidx,
	.fill_mod	= ta_fill_mod_ifidx,
	.modify		= ta_modify_ifidx,
	.flush_mod	= ta_flush_mod_ifidx,
	.change_ti	= ta_change_ti_ifidx,
};

/*
 * Number array cmds.
 *
 * Implementation:
 *
 * Runtime part:
 * - sorted array of "struct numarray" pointed by ti->state.
 *   Array is allocated with rounding up to NUMARRAY_CHUNK.
 * - current array size is stored in ti->data
 *
 */

struct numarray {
	uint32_t	number;
	uint32_t	value;
};

struct numarray_cfg {
	void	*main_ptr;
	size_t	size;	/* Number of items allocated in array */
	size_t	used;	/* Number of items _active_ now */
};

struct ta_buf_numarray
{
	struct numarray na;
};

int compare_numarray(const void *k, const void *v);

int
compare_numarray(const void *k, const void *v)
{
	const struct numarray *na;
	uint32_t key;

	key = *((const uint32_t *)k);
	na = (const struct numarray *)v;

	if (key < na->number)
		return (-1);
	else if (key > na->number)
		return (1);

	return (0);
}

static struct numarray *
numarray_find(struct table_info *ti, void *key)
{
	struct numarray *ri;

	ri = bsearch(key, ti->state, ti->data, sizeof(struct numarray),
	    compare_ifidx);

	return (ri);
}

static int
ta_lookup_numarray(struct table_info *ti, void *key, uint32_t keylen,
    uint32_t *val)
{
	struct numarray *ri;

	ri = numarray_find(ti, key);

	if (ri != NULL) {
		*val = ri->value;
		return (1);
	}

	return (0);
}

static int
ta_init_numarray(struct ip_fw_chain *ch, void **ta_state, struct table_info *ti,
    char *data, uint8_t tflags)
{
	struct numarray_cfg *cfg;

	cfg = malloc(sizeof(*cfg), M_IPFW, M_WAITOK | M_ZERO);

	cfg->size = 16;
	cfg->main_ptr = malloc(sizeof(struct numarray) * cfg->size, M_IPFW,
	    M_WAITOK | M_ZERO);

	*ta_state = cfg;
	ti->state = cfg->main_ptr;
	ti->lookup = ta_lookup_numarray;

	return (0);
}

/*
 * Destroys table @ti
 */
static void
ta_destroy_numarray(void *ta_state, struct table_info *ti)
{
	struct numarray_cfg *cfg;

	cfg = (struct numarray_cfg *)ta_state;

	if (cfg->main_ptr != NULL)
		free(cfg->main_ptr, M_IPFW);

	free(cfg, M_IPFW);
}

/*
 * Provide algo-specific table info
 */
static void
ta_dump_numarray_tinfo(void *ta_state, struct table_info *ti, ipfw_ta_tinfo *tinfo)
{
	struct numarray_cfg *cfg;

	cfg = (struct numarray_cfg *)ta_state;

	tinfo->taclass4 = IPFW_TACLASS_ARRAY;
	tinfo->size4 = cfg->size;
	tinfo->count4 = cfg->used;
	tinfo->itemsize4 = sizeof(struct numarray);
}

/*
 * Prepare for addition/deletion to an array.
 */
static int
ta_prepare_add_numarray(struct ip_fw_chain *ch, struct tentry_info *tei,
    void *ta_buf)
{
	struct ta_buf_numarray *tb;

	tb = (struct ta_buf_numarray *)ta_buf;

	tb->na.number = *((uint32_t *)tei->paddr);

	return (0);
}

static int
ta_add_numarray(void *ta_state, struct table_info *ti, struct tentry_info *tei,
    void *ta_buf, uint32_t *pnum)
{
	struct numarray_cfg *cfg;
	struct ta_buf_numarray *tb;
	struct numarray *ri;
	int res;
	uint32_t value;

	tb = (struct ta_buf_numarray *)ta_buf;
	cfg = (struct numarray_cfg *)ta_state;

	/* Read current value from @tei */
	tb->na.value = tei->value;

	ri = numarray_find(ti, &tb->na.number);

	if (ri != NULL) {
		if ((tei->flags & TEI_FLAGS_UPDATE) == 0)
			return (EEXIST);

		/* Exchange values between ri and @tei */
		value = ri->value;
		ri->value = tei->value;
		tei->value = value;
		/* Indicate that update has happened instead of addition */
		tei->flags |= TEI_FLAGS_UPDATED;
		*pnum = 0;
		return (0);
	}

	if ((tei->flags & TEI_FLAGS_DONTADD) != 0)
		return (EFBIG);

	res = badd(&tb->na.number, &tb->na, cfg->main_ptr, cfg->used,
	    sizeof(struct numarray), compare_numarray);

	KASSERT(res == 1, ("number %d already exists", tb->na.number));
	cfg->used++;
	ti->data = cfg->used;
	*pnum = 1;

	return (0);
}

/*
 * Remove key from both configuration list and
 * runtime array. Removed interface notification.
 */
static int
ta_del_numarray(void *ta_state, struct table_info *ti, struct tentry_info *tei,
    void *ta_buf, uint32_t *pnum)
{
	struct numarray_cfg *cfg;
	struct ta_buf_numarray *tb;
	struct numarray *ri;
	int res;

	tb = (struct ta_buf_numarray *)ta_buf;
	cfg = (struct numarray_cfg *)ta_state;

	ri = numarray_find(ti, &tb->na.number);
	if (ri == NULL)
		return (ENOENT);

	tei->value = ri->value;

	res = bdel(&tb->na.number, cfg->main_ptr, cfg->used,
	    sizeof(struct numarray), compare_numarray);

	KASSERT(res == 1, ("number %u does not exist", tb->na.number));
	cfg->used--;
	ti->data = cfg->used;
	*pnum = 1;

	return (0);
}

static void
ta_flush_numarray_entry(struct ip_fw_chain *ch, struct tentry_info *tei,
    void *ta_buf)
{

	/* We don't have any state, do nothing */
}


/*
 * Table growing callbacks.
 */

static int
ta_need_modify_numarray(void *ta_state, struct table_info *ti, uint32_t count,
    uint64_t *pflags)
{
	struct numarray_cfg *cfg;
	size_t size;

	cfg = (struct numarray_cfg *)ta_state;

	size = cfg->size;
	while (size < cfg->used + count)
		size *= 2;

	if (size != cfg->size) {
		*pflags = size;
		return (1);
	}

	return (0);
}

/*
 * Allocate new, larger runtime array.
 */
static int
ta_prepare_mod_numarray(void *ta_buf, uint64_t *pflags)
{
	struct mod_item *mi;

	mi = (struct mod_item *)ta_buf;

	memset(mi, 0, sizeof(struct mod_item));
	mi->size = *pflags;
	mi->main_ptr = malloc(sizeof(struct numarray) * mi->size, M_IPFW,
	    M_WAITOK | M_ZERO);

	return (0);
}

/*
 * Copy data from old runtime array to new one.
 */
static int
ta_fill_mod_numarray(void *ta_state, struct table_info *ti, void *ta_buf,
    uint64_t *pflags)
{
	struct mod_item *mi;
	struct numarray_cfg *cfg;

	mi = (struct mod_item *)ta_buf;
	cfg = (struct numarray_cfg *)ta_state;

	/* Check if we still need to grow array */
	if (cfg->size >= mi->size) {
		*pflags = 0;
		return (0);
	}

	memcpy(mi->main_ptr, cfg->main_ptr, cfg->used * sizeof(struct numarray));

	return (0);
}

/*
 * Switch old & new arrays.
 */
static void
ta_modify_numarray(void *ta_state, struct table_info *ti, void *ta_buf,
    uint64_t pflags)
{
	struct mod_item *mi;
	struct numarray_cfg *cfg;
	void *old_ptr;

	mi = (struct mod_item *)ta_buf;
	cfg = (struct numarray_cfg *)ta_state;

	old_ptr = cfg->main_ptr;
	cfg->main_ptr = mi->main_ptr;
	cfg->size = mi->size;
	ti->state = cfg->main_ptr;

	mi->main_ptr = old_ptr;
}

/*
 * Free unneded array.
 */
static void
ta_flush_mod_numarray(void *ta_buf)
{
	struct mod_item *mi;

	mi = (struct mod_item *)ta_buf;
	if (mi->main_ptr != NULL)
		free(mi->main_ptr, M_IPFW);
}

static int
ta_dump_numarray_tentry(void *ta_state, struct table_info *ti, void *e,
    ipfw_obj_tentry *tent)
{
	struct numarray *na;

	na = (struct numarray *)e;

	tent->k.key = na->number;
	tent->v.kidx = na->value;

	return (0);
}

static int
ta_find_numarray_tentry(void *ta_state, struct table_info *ti,
    ipfw_obj_tentry *tent)
{
	struct numarray_cfg *cfg;
	struct numarray *ri;

	cfg = (struct numarray_cfg *)ta_state;

	ri = numarray_find(ti, &tent->k.key);

	if (ri != NULL) {
		ta_dump_numarray_tentry(ta_state, ti, ri, tent);
		return (0);
	}

	return (ENOENT);
}

static void
ta_foreach_numarray(void *ta_state, struct table_info *ti, ta_foreach_f *f,
    void *arg)
{
	struct numarray_cfg *cfg;
	struct numarray *array;
	int i;

	cfg = (struct numarray_cfg *)ta_state;
	array = cfg->main_ptr;

	for (i = 0; i < cfg->used; i++)
		f(&array[i], arg);
}

struct table_algo number_array = {
	.name		= "number:array",
	.type		= IPFW_TABLE_NUMBER,
	.ta_buf_size	= sizeof(struct ta_buf_numarray),
	.init		= ta_init_numarray,
	.destroy	= ta_destroy_numarray,
	.prepare_add	= ta_prepare_add_numarray,
	.prepare_del	= ta_prepare_add_numarray,
	.add		= ta_add_numarray,
	.del		= ta_del_numarray,
	.flush_entry	= ta_flush_numarray_entry,
	.foreach	= ta_foreach_numarray,
	.dump_tentry	= ta_dump_numarray_tentry,
	.find_tentry	= ta_find_numarray_tentry,
	.dump_tinfo	= ta_dump_numarray_tinfo,
	.need_modify	= ta_need_modify_numarray,
	.prepare_mod	= ta_prepare_mod_numarray,
	.fill_mod	= ta_fill_mod_numarray,
	.modify		= ta_modify_numarray,
	.flush_mod	= ta_flush_mod_numarray,
};

/*
 * flow:hash cmds
 *
 *
 * ti->data:
 * [inv.mask4][inv.mask6][log2hsize4][log2hsize6]
 * [        8][        8[          8][         8]
 *
 * inv.mask4: 32 - mask
 * inv.mask6:
 * 1) _slow lookup: mask
 * 2) _aligned: (128 - mask) / 8
 * 3) _64: 8
 *
 *
 * pflags:
 * [hsize4][hsize6]
 * [    16][    16]
 */

struct fhashentry;

SLIST_HEAD(fhashbhead, fhashentry);

struct fhashentry {
	SLIST_ENTRY(fhashentry)	next;
	uint8_t		af;
	uint8_t		proto;
	uint16_t	spare0;
	uint16_t	dport;
	uint16_t	sport;
	uint32_t	value;
	uint32_t	spare1;
};

struct fhashentry4 {
	struct fhashentry	e;
	struct in_addr		dip;
	struct in_addr		sip;
};

struct fhashentry6 {
	struct fhashentry	e;
	struct in6_addr		dip6;
	struct in6_addr		sip6;
};

struct fhash_cfg {
	struct fhashbhead	*head;
	size_t			size;
	size_t			items;
	struct fhashentry4	fe4;
	struct fhashentry6	fe6;
};

struct ta_buf_fhash {
	void	*ent_ptr;
	struct fhashentry6 fe6;
};

static __inline int
cmp_flow_ent(struct fhashentry *a, struct fhashentry *b, size_t sz)
{
	uint64_t *ka, *kb;

	ka = (uint64_t *)(&a->next + 1);
	kb = (uint64_t *)(&b->next + 1);

	if (*ka == *kb && (memcmp(a + 1, b + 1, sz) == 0))
		return (1);

	return (0);
}

static __inline uint32_t
hash_flow4(struct fhashentry4 *f, int hsize)
{
	uint32_t i;

	i = (f->dip.s_addr) ^ (f->sip.s_addr) ^ (f->e.dport) ^ (f->e.sport);

	return (i % (hsize - 1));
}

static __inline uint32_t
hash_flow6(struct fhashentry6 *f, int hsize)
{
	uint32_t i;

	i = (f->dip6.__u6_addr.__u6_addr32[2]) ^
	    (f->dip6.__u6_addr.__u6_addr32[3]) ^
	    (f->sip6.__u6_addr.__u6_addr32[2]) ^
	    (f->sip6.__u6_addr.__u6_addr32[3]) ^
	    (f->e.dport) ^ (f->e.sport);

	return (i % (hsize - 1));
}

static uint32_t
hash_flow_ent(struct fhashentry *ent, uint32_t size)
{
	uint32_t hash;

	if (ent->af == AF_INET) {
		hash = hash_flow4((struct fhashentry4 *)ent, size);
	} else {
		hash = hash_flow6((struct fhashentry6 *)ent, size);
	}

	return (hash);
}

static int
ta_lookup_fhash(struct table_info *ti, void *key, uint32_t keylen,
    uint32_t *val)
{
	struct fhashbhead *head;
	struct fhashentry *ent;
	struct fhashentry4 *m4;
	struct ipfw_flow_id *id;
	uint16_t hash, hsize;

	id = (struct ipfw_flow_id *)key;
	head = (struct fhashbhead *)ti->state;
	hsize = ti->data;
	m4 = (struct fhashentry4 *)ti->xstate;

	if (id->addr_type == 4) {
		struct fhashentry4 f;

		/* Copy hash mask */
		f = *m4;

		f.dip.s_addr &= id->dst_ip;
		f.sip.s_addr &= id->src_ip;
		f.e.dport &= id->dst_port;
		f.e.sport &= id->src_port;
		f.e.proto &= id->proto;
		hash = hash_flow4(&f, hsize);
		SLIST_FOREACH(ent, &head[hash], next) {
			if (cmp_flow_ent(ent, &f.e, 2 * 4) != 0) {
				*val = ent->value;
				return (1);
			}
		}
	} else if (id->addr_type == 6) {
		struct fhashentry6 f;
		uint64_t *fp, *idp;

		/* Copy hash mask */
		f = *((struct fhashentry6 *)(m4 + 1));

		/* Handle lack of __u6_addr.__u6_addr64 */
		fp = (uint64_t *)&f.dip6;
		idp = (uint64_t *)&id->dst_ip6;
		/* src IPv6 is stored after dst IPv6 */
		*fp++ &= *idp++;
		*fp++ &= *idp++;
		*fp++ &= *idp++;
		*fp &= *idp;
		f.e.dport &= id->dst_port;
		f.e.sport &= id->src_port;
		f.e.proto &= id->proto;
		hash = hash_flow6(&f, hsize);
		SLIST_FOREACH(ent, &head[hash], next) {
			if (cmp_flow_ent(ent, &f.e, 2 * 16) != 0) {
				*val = ent->value;
				return (1);
			}
		}
	}

	return (0);
}

/*
 * New table.
 */
static int
ta_init_fhash(struct ip_fw_chain *ch, void **ta_state, struct table_info *ti,
    char *data, uint8_t tflags)
{
	int i;
	struct fhash_cfg *cfg;
	struct fhashentry4 *fe4;
	struct fhashentry6 *fe6;

	cfg = malloc(sizeof(struct fhash_cfg), M_IPFW, M_WAITOK | M_ZERO);

	cfg->size = 512;

	cfg->head = malloc(sizeof(struct fhashbhead) * cfg->size, M_IPFW,
	    M_WAITOK | M_ZERO);
	for (i = 0; i < cfg->size; i++)
		SLIST_INIT(&cfg->head[i]);

	/* Fill in fe masks based on @tflags */
	fe4 = &cfg->fe4;
	fe6 = &cfg->fe6;
	if (tflags & IPFW_TFFLAG_SRCIP) {
		memset(&fe4->sip, 0xFF, sizeof(fe4->sip));
		memset(&fe6->sip6, 0xFF, sizeof(fe6->sip6));
	}
	if (tflags & IPFW_TFFLAG_DSTIP) {
		memset(&fe4->dip, 0xFF, sizeof(fe4->dip));
		memset(&fe6->dip6, 0xFF, sizeof(fe6->dip6));
	}
	if (tflags & IPFW_TFFLAG_SRCPORT) {
		memset(&fe4->e.sport, 0xFF, sizeof(fe4->e.sport));
		memset(&fe6->e.sport, 0xFF, sizeof(fe6->e.sport));
	}
	if (tflags & IPFW_TFFLAG_DSTPORT) {
		memset(&fe4->e.dport, 0xFF, sizeof(fe4->e.dport));
		memset(&fe6->e.dport, 0xFF, sizeof(fe6->e.dport));
	}
	if (tflags & IPFW_TFFLAG_PROTO) {
		memset(&fe4->e.proto, 0xFF, sizeof(fe4->e.proto));
		memset(&fe6->e.proto, 0xFF, sizeof(fe6->e.proto));
	}

	fe4->e.af = AF_INET;
	fe6->e.af = AF_INET6;

	*ta_state = cfg;
	ti->state = cfg->head;
	ti->xstate = &cfg->fe4;
	ti->data = cfg->size;
	ti->lookup = ta_lookup_fhash;

	return (0);
}

static void
ta_destroy_fhash(void *ta_state, struct table_info *ti)
{
	struct fhash_cfg *cfg;
	struct fhashentry *ent, *ent_next;
	int i;

	cfg = (struct fhash_cfg *)ta_state;

	for (i = 0; i < cfg->size; i++)
		SLIST_FOREACH_SAFE(ent, &cfg->head[i], next, ent_next)
			free(ent, M_IPFW_TBL);

	free(cfg->head, M_IPFW);
	free(cfg, M_IPFW);
}

/*
 * Provide algo-specific table info
 */
static void
ta_dump_fhash_tinfo(void *ta_state, struct table_info *ti, ipfw_ta_tinfo *tinfo)
{
	struct fhash_cfg *cfg;

	cfg = (struct fhash_cfg *)ta_state;

	tinfo->flags = IPFW_TATFLAGS_AFITEM;
	tinfo->taclass4 = IPFW_TACLASS_HASH;
	tinfo->size4 = cfg->size;
	tinfo->count4 = cfg->items;
	tinfo->itemsize4 = sizeof(struct fhashentry4);
	tinfo->itemsize6 = sizeof(struct fhashentry6);
}

static int
ta_dump_fhash_tentry(void *ta_state, struct table_info *ti, void *e,
    ipfw_obj_tentry *tent)
{
	struct fhash_cfg *cfg;
	struct fhashentry *ent;
	struct fhashentry4 *fe4;
	struct fhashentry6 *fe6;
	struct tflow_entry *tfe;

	cfg = (struct fhash_cfg *)ta_state;
	ent = (struct fhashentry *)e;
	tfe = &tent->k.flow;

	tfe->af = ent->af;
	tfe->proto = ent->proto;
	tfe->dport = htons(ent->dport);
	tfe->sport = htons(ent->sport);
	tent->v.kidx = ent->value;
	tent->subtype = ent->af;

	if (ent->af == AF_INET) {
		fe4 = (struct fhashentry4 *)ent;
		tfe->a.a4.sip.s_addr = htonl(fe4->sip.s_addr);
		tfe->a.a4.dip.s_addr = htonl(fe4->dip.s_addr);
		tent->masklen = 32;
#ifdef INET6
	} else {
		fe6 = (struct fhashentry6 *)ent;
		tfe->a.a6.sip6 = fe6->sip6;
		tfe->a.a6.dip6 = fe6->dip6;
		tent->masklen = 128;
#endif
	}

	return (0);
}

static int
tei_to_fhash_ent(struct tentry_info *tei, struct fhashentry *ent)
{
	struct fhashentry4 *fe4;
	struct fhashentry6 *fe6;
	struct tflow_entry *tfe;

	tfe = (struct tflow_entry *)tei->paddr;

	ent->af = tei->subtype;
	ent->proto = tfe->proto;
	ent->dport = ntohs(tfe->dport);
	ent->sport = ntohs(tfe->sport);

	if (tei->subtype == AF_INET) {
#ifdef INET
		fe4 = (struct fhashentry4 *)ent;
		fe4->sip.s_addr = ntohl(tfe->a.a4.sip.s_addr);
		fe4->dip.s_addr = ntohl(tfe->a.a4.dip.s_addr);
#endif
#ifdef INET6
	} else if (tei->subtype == AF_INET6) {
		fe6 = (struct fhashentry6 *)ent;
		fe6->sip6 = tfe->a.a6.sip6;
		fe6->dip6 = tfe->a.a6.dip6;
#endif
	} else {
		/* Unknown CIDR type */
		return (EINVAL);
	}

	return (0);
}


static int
ta_find_fhash_tentry(void *ta_state, struct table_info *ti,
    ipfw_obj_tentry *tent)
{
	struct fhash_cfg *cfg;
	struct fhashbhead *head;
	struct fhashentry *ent, *tmp;
	struct fhashentry6 fe6;
	struct tentry_info tei;
	int error;
	uint32_t hash;
	size_t sz;

	cfg = (struct fhash_cfg *)ta_state;

	ent = &fe6.e;

	memset(&fe6, 0, sizeof(fe6));
	memset(&tei, 0, sizeof(tei));

	tei.paddr = &tent->k.flow;
	tei.subtype = tent->subtype;

	if ((error = tei_to_fhash_ent(&tei, ent)) != 0)
		return (error);

	head = cfg->head;
	hash = hash_flow_ent(ent, cfg->size);

	if (tei.subtype == AF_INET)
		sz = 2 * sizeof(struct in_addr);
	else
		sz = 2 * sizeof(struct in6_addr);

	/* Check for existence */
	SLIST_FOREACH(tmp, &head[hash], next) {
		if (cmp_flow_ent(tmp, ent, sz) != 0) {
			ta_dump_fhash_tentry(ta_state, ti, tmp, tent);
			return (0);
		}
	}

	return (ENOENT);
}

static void
ta_foreach_fhash(void *ta_state, struct table_info *ti, ta_foreach_f *f,
    void *arg)
{
	struct fhash_cfg *cfg;
	struct fhashentry *ent, *ent_next;
	int i;

	cfg = (struct fhash_cfg *)ta_state;

	for (i = 0; i < cfg->size; i++)
		SLIST_FOREACH_SAFE(ent, &cfg->head[i], next, ent_next)
			f(ent, arg);
}

static int
ta_prepare_add_fhash(struct ip_fw_chain *ch, struct tentry_info *tei,
    void *ta_buf)
{
	struct ta_buf_fhash *tb;
	struct fhashentry *ent;
	size_t sz;
	int error;

	tb = (struct ta_buf_fhash *)ta_buf;

	if (tei->subtype == AF_INET)
		sz = sizeof(struct fhashentry4);
	else if (tei->subtype == AF_INET6)
		sz = sizeof(struct fhashentry6);
	else
		return (EINVAL);

	ent = malloc(sz, M_IPFW_TBL, M_WAITOK | M_ZERO);

	error = tei_to_fhash_ent(tei, ent);
	if (error != 0) {
		free(ent, M_IPFW_TBL);
		return (error);
	}
	tb->ent_ptr = ent;

	return (0);
}

static int
ta_add_fhash(void *ta_state, struct table_info *ti, struct tentry_info *tei,
    void *ta_buf, uint32_t *pnum)
{
	struct fhash_cfg *cfg;
	struct fhashbhead *head;
	struct fhashentry *ent, *tmp;
	struct ta_buf_fhash *tb;
	int exists;
	uint32_t hash, value;
	size_t sz;

	cfg = (struct fhash_cfg *)ta_state;
	tb = (struct ta_buf_fhash *)ta_buf;
	ent = (struct fhashentry *)tb->ent_ptr;
	exists = 0;

	/* Read current value from @tei */
	ent->value = tei->value;

	head = cfg->head;
	hash = hash_flow_ent(ent, cfg->size);

	if (tei->subtype == AF_INET)
		sz = 2 * sizeof(struct in_addr);
	else
		sz = 2 * sizeof(struct in6_addr);

	/* Check for existence */
	SLIST_FOREACH(tmp, &head[hash], next) {
		if (cmp_flow_ent(tmp, ent, sz) != 0) {
			exists = 1;
			break;
		}
	}

	if (exists == 1) {
		if ((tei->flags & TEI_FLAGS_UPDATE) == 0)
			return (EEXIST);
		/* Record already exists. Update value if we're asked to */
		/* Exchange values between tmp and @tei */
		value = tmp->value;
		tmp->value = tei->value;
		tei->value = value;
		/* Indicate that update has happened instead of addition */
		tei->flags |= TEI_FLAGS_UPDATED;
		*pnum = 0;
	} else {
		if ((tei->flags & TEI_FLAGS_DONTADD) != 0)
			return (EFBIG);

		SLIST_INSERT_HEAD(&head[hash], ent, next);
		tb->ent_ptr = NULL;
		*pnum = 1;

		/* Update counters and check if we need to grow hash */
		cfg->items++;
	}

	return (0);
}

static int
ta_prepare_del_fhash(struct ip_fw_chain *ch, struct tentry_info *tei,
    void *ta_buf)
{
	struct ta_buf_fhash *tb;

	tb = (struct ta_buf_fhash *)ta_buf;

	return (tei_to_fhash_ent(tei, &tb->fe6.e));
}

static int
ta_del_fhash(void *ta_state, struct table_info *ti, struct tentry_info *tei,
    void *ta_buf, uint32_t *pnum)
{
	struct fhash_cfg *cfg;
	struct fhashbhead *head;
	struct fhashentry *ent, *tmp;
	struct ta_buf_fhash *tb;
	uint32_t hash;
	size_t sz;

	cfg = (struct fhash_cfg *)ta_state;
	tb = (struct ta_buf_fhash *)ta_buf;
	ent = &tb->fe6.e;

	head = cfg->head;
	hash = hash_flow_ent(ent, cfg->size);

	if (tei->subtype == AF_INET)
		sz = 2 * sizeof(struct in_addr);
	else
		sz = 2 * sizeof(struct in6_addr);

	/* Check for existence */
	SLIST_FOREACH(tmp, &head[hash], next) {
		if (cmp_flow_ent(tmp, ent, sz) == 0)
			continue;

		SLIST_REMOVE(&head[hash], tmp, fhashentry, next);
		tei->value = tmp->value;
		*pnum = 1;
		cfg->items--;
		tb->ent_ptr = tmp;
		return (0);
	}

	return (ENOENT);
}

static void
ta_flush_fhash_entry(struct ip_fw_chain *ch, struct tentry_info *tei,
    void *ta_buf)
{
	struct ta_buf_fhash *tb;

	tb = (struct ta_buf_fhash *)ta_buf;

	if (tb->ent_ptr != NULL)
		free(tb->ent_ptr, M_IPFW_TBL);
}

/*
 * Hash growing callbacks.
 */

static int
ta_need_modify_fhash(void *ta_state, struct table_info *ti, uint32_t count,
    uint64_t *pflags)
{
	struct fhash_cfg *cfg;

	cfg = (struct fhash_cfg *)ta_state;

	if (cfg->items > cfg->size && cfg->size < 65536) {
		*pflags = cfg->size * 2;
		return (1);
	}

	return (0);
}

/*
 * Allocate new, larger fhash.
 */
static int
ta_prepare_mod_fhash(void *ta_buf, uint64_t *pflags)
{
	struct mod_item *mi;
	struct fhashbhead *head;
	int i;

	mi = (struct mod_item *)ta_buf;

	memset(mi, 0, sizeof(struct mod_item));
	mi->size = *pflags;
	head = malloc(sizeof(struct fhashbhead) * mi->size, M_IPFW,
	    M_WAITOK | M_ZERO);
	for (i = 0; i < mi->size; i++)
		SLIST_INIT(&head[i]);

	mi->main_ptr = head;

	return (0);
}

/*
 * Copy data from old runtime array to new one.
 */
static int
ta_fill_mod_fhash(void *ta_state, struct table_info *ti, void *ta_buf,
    uint64_t *pflags)
{

	/* In is not possible to do rehash if we're not holidng WLOCK. */
	return (0);
}

/*
 * Switch old & new arrays.
 */
static void
ta_modify_fhash(void *ta_state, struct table_info *ti, void *ta_buf,
    uint64_t pflags)
{
	struct mod_item *mi;
	struct fhash_cfg *cfg;
	struct fhashbhead *old_head, *new_head;
	struct fhashentry *ent, *ent_next;
	int i;
	uint32_t nhash;
	size_t old_size;

	mi = (struct mod_item *)ta_buf;
	cfg = (struct fhash_cfg *)ta_state;

	old_size = cfg->size;
	old_head = ti->state;

	new_head = (struct fhashbhead *)mi->main_ptr;
	for (i = 0; i < old_size; i++) {
		SLIST_FOREACH_SAFE(ent, &old_head[i], next, ent_next) {
			nhash = hash_flow_ent(ent, mi->size);
			SLIST_INSERT_HEAD(&new_head[nhash], ent, next);
		}
	}

	ti->state = new_head;
	ti->data = mi->size;
	cfg->head = new_head;
	cfg->size = mi->size;

	mi->main_ptr = old_head;
}

/*
 * Free unneded array.
 */
static void
ta_flush_mod_fhash(void *ta_buf)
{
	struct mod_item *mi;

	mi = (struct mod_item *)ta_buf;
	if (mi->main_ptr != NULL)
		free(mi->main_ptr, M_IPFW);
}

struct table_algo flow_hash = {
	.name		= "flow:hash",
	.type		= IPFW_TABLE_FLOW,
	.flags		= TA_FLAG_DEFAULT,
	.ta_buf_size	= sizeof(struct ta_buf_fhash),
	.init		= ta_init_fhash,
	.destroy	= ta_destroy_fhash,
	.prepare_add	= ta_prepare_add_fhash,
	.prepare_del	= ta_prepare_del_fhash,
	.add		= ta_add_fhash,
	.del		= ta_del_fhash,
	.flush_entry	= ta_flush_fhash_entry,
	.foreach	= ta_foreach_fhash,
	.dump_tentry	= ta_dump_fhash_tentry,
	.find_tentry	= ta_find_fhash_tentry,
	.dump_tinfo	= ta_dump_fhash_tinfo,
	.need_modify	= ta_need_modify_fhash,
	.prepare_mod	= ta_prepare_mod_fhash,
	.fill_mod	= ta_fill_mod_fhash,
	.modify		= ta_modify_fhash,
	.flush_mod	= ta_flush_mod_fhash,
};

/*
 * Kernel fibs bindings.
 *
 * Implementation:
 *
 * Runtime part:
 * - fully relies on route API
 * - fib number is stored in ti->data
 *
 */

static struct rtentry *
lookup_kfib(void *key, int keylen, int fib)
{
	struct sockaddr *s;

	if (keylen == 4) {
		struct sockaddr_in sin;
		bzero(&sin, sizeof(sin));
		sin.sin_len = sizeof(struct sockaddr_in);
		sin.sin_family = AF_INET;
		sin.sin_addr.s_addr = *(in_addr_t *)key;
		s = (struct sockaddr *)&sin;
	} else {
		struct sockaddr_in6 sin6;
		bzero(&sin6, sizeof(sin6));
		sin6.sin6_len = sizeof(struct sockaddr_in6);
		sin6.sin6_family = AF_INET6;
		sin6.sin6_addr = *(struct in6_addr *)key;
		s = (struct sockaddr *)&sin6;
	}

	return (rtalloc1_fib(s, 0, 0, fib));
}

static int
ta_lookup_kfib(struct table_info *ti, void *key, uint32_t keylen,
    uint32_t *val)
{
	struct rtentry *rte;

	if ((rte = lookup_kfib(key, keylen, ti->data)) == NULL)
		return (0);

	*val = 0;
	RTFREE_LOCKED(rte);

	return (1);
}

/* Parse 'fib=%d' */
static int
kfib_parse_opts(int *pfib, char *data)
{
	char *pdel, *pend, *s;
	int fibnum;

	if (data == NULL)
		return (0);
	if ((pdel = strchr(data, ' ')) == NULL)
		return (0);
	while (*pdel == ' ')
		pdel++;
	if (strncmp(pdel, "fib=", 4) != 0)
		return (EINVAL);
	if ((s = strchr(pdel, ' ')) != NULL)
		*s++ = '\0';

	pdel += 4;
	/* Need \d+ */
	fibnum = strtol(pdel, &pend, 10);
	if (*pend != '\0')
		return (EINVAL);

	*pfib = fibnum;

	return (0);
}

static void
ta_print_kfib_config(void *ta_state, struct table_info *ti, char *buf,
    size_t bufsize)
{

	if (ti->data != 0)
		snprintf(buf, bufsize, "%s fib=%lu", "addr:kfib", ti->data);
	else
		snprintf(buf, bufsize, "%s", "addr:kfib");
}

static int
ta_init_kfib(struct ip_fw_chain *ch, void **ta_state, struct table_info *ti,
    char *data, uint8_t tflags)
{
	int error, fibnum;

	fibnum = 0;
	if ((error = kfib_parse_opts(&fibnum, data)) != 0)
		return (error);

	if (fibnum >= rt_numfibs)
		return (E2BIG);

	ti->data = fibnum;
	ti->lookup = ta_lookup_kfib;

	return (0);
}

/*
 * Destroys table @ti
 */
static void
ta_destroy_kfib(void *ta_state, struct table_info *ti)
{

}

/*
 * Provide algo-specific table info
 */
static void
ta_dump_kfib_tinfo(void *ta_state, struct table_info *ti, ipfw_ta_tinfo *tinfo)
{

	tinfo->flags = IPFW_TATFLAGS_AFDATA;
	tinfo->taclass4 = IPFW_TACLASS_RADIX;
	tinfo->count4 = 0;
	tinfo->itemsize4 = sizeof(struct rtentry);
	tinfo->taclass6 = IPFW_TACLASS_RADIX;
	tinfo->count6 = 0;
	tinfo->itemsize6 = sizeof(struct rtentry);
}

static int
contigmask(uint8_t *p, int len)
{
	int i, n;

	for (i = 0; i < len ; i++)
		if ( (p[i/8] & (1 << (7 - (i%8)))) == 0) /* first bit unset */
			break;
	for (n= i + 1; n < len; n++)
		if ( (p[n/8] & (1 << (7 - (n % 8)))) != 0)
			return (-1); /* mask not contiguous */
	return (i);
}


static int
ta_dump_kfib_tentry(void *ta_state, struct table_info *ti, void *e,
    ipfw_obj_tentry *tent)
{
	struct rtentry *rte;
	struct sockaddr_in *addr, *mask;
	struct sockaddr_in6 *addr6, *mask6;
	int len;

	rte = (struct rtentry *)e;
	addr = (struct sockaddr_in *)rt_key(rte);
	mask = (struct sockaddr_in *)rt_mask(rte);
	len = 0;

	/* Guess IPv4/IPv6 radix by sockaddr family */
	if (addr->sin_family == AF_INET) {
		tent->k.addr.s_addr = addr->sin_addr.s_addr;
		len = 32;
		if (mask != NULL)
			len = contigmask((uint8_t *)&mask->sin_addr, 32);
		if (len == -1)
			len = 0;
		tent->masklen = len;
		tent->subtype = AF_INET;
		tent->v.kidx = 0; /* Do we need to put GW here? */
#ifdef INET6
	} else if (addr->sin_family == AF_INET6) {
		addr6 = (struct sockaddr_in6 *)addr;
		mask6 = (struct sockaddr_in6 *)mask;
		memcpy(&tent->k, &addr6->sin6_addr, sizeof(struct in6_addr));
		len = 128;
		if (mask6 != NULL)
			len = contigmask((uint8_t *)&mask6->sin6_addr, 128);
		if (len == -1)
			len = 0;
		tent->masklen = len;
		tent->subtype = AF_INET6;
		tent->v.kidx = 0;
#endif
	}

	return (0);
}

static int
ta_find_kfib_tentry(void *ta_state, struct table_info *ti,
    ipfw_obj_tentry *tent)
{
	struct rtentry *rte;
	void *key;
	int keylen;

	if (tent->subtype == AF_INET) {
		key = &tent->k.addr;
		keylen = sizeof(struct in_addr);
	} else {
		key = &tent->k.addr6;
		keylen = sizeof(struct in6_addr);
	}

	if ((rte = lookup_kfib(key, keylen, ti->data)) == NULL)
		return (0);

	if (rte != NULL) {
		ta_dump_kfib_tentry(ta_state, ti, rte, tent);
		RTFREE_LOCKED(rte);
		return (0);
	}

	return (ENOENT);
}

static void
ta_foreach_kfib(void *ta_state, struct table_info *ti, ta_foreach_f *f,
    void *arg)
{
	struct radix_node_head *rnh;
	int error;

	rnh = rt_tables_get_rnh(ti->data, AF_INET);
	if (rnh != NULL) {
		RADIX_NODE_HEAD_RLOCK(rnh);
		error = rnh->rnh_walktree(rnh, (walktree_f_t *)f, arg);
		RADIX_NODE_HEAD_RUNLOCK(rnh);
	}

	rnh = rt_tables_get_rnh(ti->data, AF_INET6);
	if (rnh != NULL) {
		RADIX_NODE_HEAD_RLOCK(rnh);
		error = rnh->rnh_walktree(rnh, (walktree_f_t *)f, arg);
		RADIX_NODE_HEAD_RUNLOCK(rnh);
	}
}

struct table_algo addr_kfib = {
	.name		= "addr:kfib",
	.type		= IPFW_TABLE_ADDR,
	.flags		= TA_FLAG_READONLY,
	.ta_buf_size	= 0,
	.init		= ta_init_kfib,
	.destroy	= ta_destroy_kfib,
	.foreach	= ta_foreach_kfib,
	.dump_tentry	= ta_dump_kfib_tentry,
	.find_tentry	= ta_find_kfib_tentry,
	.dump_tinfo	= ta_dump_kfib_tinfo,
	.print_config	= ta_print_kfib_config,
};

void
ipfw_table_algo_init(struct ip_fw_chain *ch)
{
	size_t sz;

	/*
	 * Register all algorithms presented here.
	 */
	sz = sizeof(struct table_algo);
	ipfw_add_table_algo(ch, &addr_radix, sz, &addr_radix.idx);
	ipfw_add_table_algo(ch, &addr_hash, sz, &addr_hash.idx);
	ipfw_add_table_algo(ch, &iface_idx, sz, &iface_idx.idx);
	ipfw_add_table_algo(ch, &number_array, sz, &number_array.idx);
	ipfw_add_table_algo(ch, &flow_hash, sz, &flow_hash.idx);
	ipfw_add_table_algo(ch, &addr_kfib, sz, &addr_kfib.idx);
	ipfw_add_table_algo(ch, &addr_dxr, sz, &addr_dxr.idx);
}

void
ipfw_table_algo_destroy(struct ip_fw_chain *ch)
{

	ipfw_del_table_algo(ch, addr_radix.idx);
	ipfw_del_table_algo(ch, addr_hash.idx);
	ipfw_del_table_algo(ch, iface_idx.idx);
	ipfw_del_table_algo(ch, number_array.idx);
	ipfw_del_table_algo(ch, flow_hash.idx);
	ipfw_del_table_algo(ch, addr_kfib.idx);
	ipfw_del_table_algo(ch, addr_dxr.idx);
}