/*      $OpenBSD: pfctl_optimize.c,v 1.51 2026/02/03 10:25:28 sashan Exp $ */

/*
 * Copyright (c) 2004 Mike Frantzen <frantzen@openbsd.org>
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

#include <sys/types.h>
#include <sys/ioctl.h>
#include <sys/socket.h>

#include <netinet/in.h>
#include <arpa/inet.h>
#include <net/if.h>
#include <net/pfvar.h>

#include <assert.h>
#include <ctype.h>
#include <err.h>
#include <errno.h>
#include <stddef.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include "pfctl_parser.h"
#include "pfctl.h"

/* The size at which a table becomes faster than individual rules */
#define TABLE_THRESHOLD         6


/* #define OPT_DEBUG    1 */
#ifdef OPT_DEBUG
# define DEBUG(str, v...) \
        printf("%s: " str "\n", __FUNCTION__ , ## v)
#else
# define DEBUG(str, v...) ((void)0)
#endif


/*
 * A container that lets us sort a superblock to optimize the skip step jumps
 */
struct pf_skip_step {
        int                             ps_count;       /* number of items */
        TAILQ_HEAD( , pf_opt_rule)      ps_rules;
        TAILQ_ENTRY(pf_skip_step)       ps_entry;
};


/*
 * A superblock is a block of adjacent rules of similar action.  If there
 * are five PASS rules in a row, they all become members of a superblock.
 * Once we have a superblock, we are free to re-order any rules within it
 * in order to improve performance; if a packet is passed, it doesn't matter
 * who passed it.
 */
struct superblock {
        TAILQ_HEAD( , pf_opt_rule)               sb_rules;
        TAILQ_ENTRY(superblock)                  sb_entry;
        struct superblock                       *sb_profiled_block;
        TAILQ_HEAD(skiplist, pf_skip_step)       sb_skipsteps[PF_SKIP_COUNT];
};
TAILQ_HEAD(superblocks, superblock);


/*
 * Description of the PF rule structure.
 */
enum {
    BARRIER,    /* the presence of the field puts the rule in its own block */
    BREAK,      /* the field may not differ between rules in a superblock */
    NOMERGE,    /* the field may not differ between rules when combined */
    COMBINED,   /* the field may itself be combined with other rules */
    DC,         /* we just don't care about the field */
    NEVER};     /* we should never see this field set?!? */
struct pf_rule_field {
        const char      *prf_name;
        int              prf_type;
        size_t           prf_offset;
        size_t           prf_size;
} pf_rule_desc[] = {
#define PF_RULE_FIELD(field, ty)        \
    {#field,                            \
    ty,                                 \
    offsetof(struct pf_rule, field),    \
    sizeof(((struct pf_rule *)0)->field)}


    /*
     * The presence of these fields in a rule put the rule in its own
     * superblock.  Thus it will not be optimized.  It also prevents the
     * rule from being re-ordered at all.
     */
    PF_RULE_FIELD(label,                BARRIER),
    PF_RULE_FIELD(prob,                 BARRIER),
    PF_RULE_FIELD(max_states,           BARRIER),
    PF_RULE_FIELD(max_src_nodes,        BARRIER),
    PF_RULE_FIELD(max_src_states,       BARRIER),
    PF_RULE_FIELD(max_src_conn,         BARRIER),
    PF_RULE_FIELD(max_src_conn_rate,    BARRIER),
    PF_RULE_FIELD(anchor,               BARRIER),       /* for now */

    /*
     * These fields must be the same between all rules in the same superblock.
     * These rules are allowed to be re-ordered but only among like rules.
     * For instance we can re-order all 'tag "foo"' rules because they have the
     * same tag.  But we can not re-order between a 'tag "foo"' and a
     * 'tag "bar"' since that would change the meaning of the ruleset.
     */
    PF_RULE_FIELD(tagname,              BREAK),
    PF_RULE_FIELD(keep_state,           BREAK),
    PF_RULE_FIELD(qname,                BREAK),
    PF_RULE_FIELD(pqname,               BREAK),
    PF_RULE_FIELD(rt,                   BREAK),
    PF_RULE_FIELD(allow_opts,           BREAK),
    PF_RULE_FIELD(rule_flag,            BREAK),
    PF_RULE_FIELD(action,               BREAK),
    PF_RULE_FIELD(log,                  BREAK),
    PF_RULE_FIELD(quick,                BREAK),
    PF_RULE_FIELD(return_ttl,           BREAK),
    PF_RULE_FIELD(overload_tblname,     BREAK),
    PF_RULE_FIELD(flush,                BREAK),
    PF_RULE_FIELD(rdr,                  BREAK),
    PF_RULE_FIELD(nat,                  BREAK),
    PF_RULE_FIELD(logif,                BREAK),
    PF_RULE_FIELD(route,                BREAK),
    PF_RULE_FIELD(rtableid,             BREAK),

    /*
     * Any fields not listed in this structure act as BREAK fields
     */


    /*
     * These fields must not differ when we merge two rules together but
     * their difference isn't enough to put the rules in different superblocks.
     * There are no problems re-ordering any rules with these fields.
     */
    PF_RULE_FIELD(af,                   NOMERGE),
    PF_RULE_FIELD(ifnot,                NOMERGE),
    PF_RULE_FIELD(ifname,               NOMERGE),       /* hack for IF groups */
    PF_RULE_FIELD(match_tag_not,        NOMERGE),
    PF_RULE_FIELD(match_tagname,        NOMERGE),
    PF_RULE_FIELD(os_fingerprint,       NOMERGE),
    PF_RULE_FIELD(timeout,              NOMERGE),
    PF_RULE_FIELD(return_icmp,          NOMERGE),
    PF_RULE_FIELD(return_icmp6,         NOMERGE),
    PF_RULE_FIELD(uid,                  NOMERGE),
    PF_RULE_FIELD(gid,                  NOMERGE),
    PF_RULE_FIELD(direction,            NOMERGE),
    PF_RULE_FIELD(proto,                NOMERGE),
    PF_RULE_FIELD(type,                 NOMERGE),
    PF_RULE_FIELD(code,                 NOMERGE),
    PF_RULE_FIELD(flags,                NOMERGE),
    PF_RULE_FIELD(flagset,              NOMERGE),
    PF_RULE_FIELD(tos,                  NOMERGE),
    PF_RULE_FIELD(src.port,             NOMERGE),
    PF_RULE_FIELD(dst.port,             NOMERGE),
    PF_RULE_FIELD(src.port_op,          NOMERGE),
    PF_RULE_FIELD(dst.port_op,          NOMERGE),
    PF_RULE_FIELD(src.neg,              NOMERGE),
    PF_RULE_FIELD(dst.neg,              NOMERGE),
    PF_RULE_FIELD(onrdomain,            NOMERGE),
    PF_RULE_FIELD(naf,                  NOMERGE),

    /* These fields can be merged */
    PF_RULE_FIELD(src.addr,             COMBINED),
    PF_RULE_FIELD(dst.addr,             COMBINED),

    /* We just don't care about these fields.  They're set by the kernel */
    PF_RULE_FIELD(skip,                 DC),
    PF_RULE_FIELD(evaluations,          DC),
    PF_RULE_FIELD(packets,              DC),
    PF_RULE_FIELD(bytes,                DC),
    PF_RULE_FIELD(kif,                  DC),
    PF_RULE_FIELD(states_cur,           DC),
    PF_RULE_FIELD(states_tot,           DC),
    PF_RULE_FIELD(src_nodes,            DC),
    PF_RULE_FIELD(nr,                   DC),
    PF_RULE_FIELD(entries,              DC),
    PF_RULE_FIELD(qid,                  DC),
    PF_RULE_FIELD(pqid,                 DC),
    PF_RULE_FIELD(anchor_relative,      DC),
    PF_RULE_FIELD(anchor_wildcard,      DC),
    PF_RULE_FIELD(tag,                  DC),
    PF_RULE_FIELD(match_tag,            DC),
    PF_RULE_FIELD(overload_tbl,         DC),

    /* These fields should never be set in a PASS/BLOCK rule XXX fix*/
    PF_RULE_FIELD(max_mss,              NEVER),
    PF_RULE_FIELD(min_ttl,              NEVER),
    PF_RULE_FIELD(set_tos,              NEVER),
};



int     addrs_combineable(struct pf_rule_addr *, struct pf_rule_addr *);
int     addrs_equal(struct pf_rule_addr *, struct pf_rule_addr *);
int     block_feedback(struct pfctl *, struct superblock *);
int     combine_rules(struct pfctl *, struct superblock *);
void    comparable_rule(struct pf_rule *, const struct pf_rule *, int);
int     construct_superblocks(struct pfctl *, struct pf_opt_queue *,
            struct superblocks *);
void    exclude_supersets(struct pf_rule *, struct pf_rule *);
int     interface_group(const char *);
int     load_feedback_profile(struct pfctl *, struct superblocks *);
int     optimize_superblock(struct pfctl *, struct superblock *);
void    remove_from_skipsteps(struct skiplist *, struct superblock *,
            struct pf_opt_rule *, struct pf_skip_step *);
int     remove_identical_rules(struct pfctl *, struct superblock *);
int     reorder_rules(struct pfctl *, struct superblock *, int);
int     rules_combineable(struct pf_rule *, struct pf_rule *);
void    skip_append(struct superblock *, int, struct pf_skip_step *,
            struct pf_opt_rule *);
int     skip_compare(int, struct pf_skip_step *, struct pf_opt_rule *);
void    skip_init(void);
int     skip_cmp_af(struct pf_rule *, struct pf_rule *);
int     skip_cmp_dir(struct pf_rule *, struct pf_rule *);
int     skip_cmp_rdom(struct pf_rule *, struct pf_rule *);
int     skip_cmp_dst_addr(struct pf_rule *, struct pf_rule *);
int     skip_cmp_dst_port(struct pf_rule *, struct pf_rule *);
int     skip_cmp_ifp(struct pf_rule *, struct pf_rule *);
int     skip_cmp_proto(struct pf_rule *, struct pf_rule *);
int     skip_cmp_src_addr(struct pf_rule *, struct pf_rule *);
int     skip_cmp_src_port(struct pf_rule *, struct pf_rule *);
int     superblock_inclusive(struct superblock *, struct pf_opt_rule *);
void    superblock_free(struct pfctl *, struct superblock *);
struct  pf_opt_tbl *pf_opt_table_ref(struct pf_opt_tbl *);
void    pf_opt_table_unref(struct pf_opt_tbl *);


int (*skip_comparitors[PF_SKIP_COUNT])(struct pf_rule *, struct pf_rule *);
const char *skip_comparitors_names[PF_SKIP_COUNT];
#define PF_SKIP_COMPARITORS {                           \
    { "ifp", PF_SKIP_IFP, skip_cmp_ifp },               \
    { "dir", PF_SKIP_DIR, skip_cmp_dir },               \
    { "rdomain", PF_SKIP_RDOM, skip_cmp_rdom },         \
    { "af", PF_SKIP_AF, skip_cmp_af },                  \
    { "proto", PF_SKIP_PROTO, skip_cmp_proto },         \
    { "saddr", PF_SKIP_SRC_ADDR, skip_cmp_src_addr },   \
    { "daddr", PF_SKIP_DST_ADDR, skip_cmp_dst_addr },   \
    { "sport", PF_SKIP_SRC_PORT, skip_cmp_src_port },   \
    { "dport", PF_SKIP_DST_PORT, skip_cmp_dst_port }    \
}

struct pfr_buffer table_buffer;
int table_identifier;


int
pfctl_optimize_ruleset(struct pfctl *pf, struct pf_ruleset *rs)
{
        struct superblocks superblocks;
        struct pf_opt_queue opt_queue;
        struct superblock *block;
        struct pf_opt_rule *por;
        struct pf_rule *r;
        struct pf_rulequeue *old_rules;

        if (TAILQ_EMPTY(rs->rules.active.ptr))
                return (0);

        DEBUG("optimizing ruleset \"%s\"", rs->anchor->path);
        memset(&table_buffer, 0, sizeof(table_buffer));
        skip_init();
        TAILQ_INIT(&opt_queue);

        old_rules = rs->rules.active.ptr;
        rs->rules.active.ptr = rs->rules.inactive.ptr;
        rs->rules.inactive.ptr = old_rules;

        /*
         * XXX expanding the pf_opt_rule format throughout pfctl might allow
         * us to avoid all this copying.
         */
        while ((r = TAILQ_FIRST(rs->rules.inactive.ptr)) != NULL) {
                TAILQ_REMOVE(rs->rules.inactive.ptr, r, entries);
                if ((por = calloc(1, sizeof(*por))) == NULL)
                        err(1, "calloc");
                memcpy(&por->por_rule, r, sizeof(*r));

                TAILQ_INSERT_TAIL(&opt_queue, por, por_entry);
        }

        TAILQ_INIT(&superblocks);
        if (construct_superblocks(pf, &opt_queue, &superblocks))
                goto error;

        if (pf->optimize & PF_OPTIMIZE_PROFILE) {
                if (load_feedback_profile(pf, &superblocks))
                        goto error;
        }

        TAILQ_FOREACH(block, &superblocks, sb_entry) {
                if (optimize_superblock(pf, block))
                        goto error;
        }

        rs->anchor->refcnt = 0;
        while ((block = TAILQ_FIRST(&superblocks))) {
                TAILQ_REMOVE(&superblocks, block, sb_entry);

                while ((por = TAILQ_FIRST(&block->sb_rules))) {
                        TAILQ_REMOVE(&block->sb_rules, por, por_entry);
                        por->por_rule.nr = rs->anchor->refcnt++;
                        if ((r = calloc(1, sizeof(*r))) == NULL)
                                err(1, "calloc");
                        memcpy(r, &por->por_rule, sizeof(*r));
                        TAILQ_INSERT_TAIL(rs->rules.active.ptr, r, entries);
                        pf_opt_table_unref(por->por_src_tbl);
                        pf_opt_table_unref(por->por_dst_tbl);
                        free(por);
                }
                superblock_free(pf, block);
        }

        return (0);

error:
        while ((por = TAILQ_FIRST(&opt_queue))) {
                TAILQ_REMOVE(&opt_queue, por, por_entry);
                pf_opt_table_unref(por->por_src_tbl);
                pf_opt_table_unref(por->por_dst_tbl);
                free(por);
        }
        while ((block = TAILQ_FIRST(&superblocks))) {
                TAILQ_REMOVE(&superblocks, block, sb_entry);
                superblock_free(pf, block);
        }
        return (1);
}


/*
 * Go ahead and optimize a superblock
 */
int
optimize_superblock(struct pfctl *pf, struct superblock *block)
{
#ifdef OPT_DEBUG
        struct pf_opt_rule *por;
#endif /* OPT_DEBUG */

        /* We have a few optimization passes:
         *   1) remove duplicate rules or rules that are a subset of other
         *      rules
         *   2) combine otherwise identical rules with different IP addresses
         *      into a single rule and put the addresses in a table.
         *   3) re-order the rules to improve kernel skip steps
         *   4) re-order the 'quick' rules based on feedback from the
         *      active ruleset statistics
         *
         * XXX combine_rules() doesn't combine v4 and v6 rules.  would just
         *     have to keep af in the table container, make af 'COMBINE' and
         *     twiddle the af on the merged rule
         * XXX maybe add a weighting to the metric on skipsteps when doing
         *     reordering.  sometimes two sequential tables will be better
         *     that four consecutive interfaces.
         * XXX need to adjust the skipstep count of everything after PROTO,
         *     since they aren't actually checked on a proto mismatch in
         *     pf_test_{tcp, udp, icmp}()
         * XXX should i treat proto=0, af=0 or dir=0 special in skepstep
         *     calculation since they are a DC?
         * XXX keep last skiplist of last superblock to influence this
         *     superblock.  '5 inet6 log' should make '3 inet6' come before '4
         *     inet' in the next superblock.
         * XXX would be useful to add tables for ports
         * XXX we can also re-order some mutually exclusive superblocks to
         *     try merging superblocks before any of these optimization passes.
         *     for instance a single 'log in' rule in the middle of non-logging
         *     out rules.
         */

        /* shortcut.  there will be a lot of 1-rule superblocks */
        if (!TAILQ_NEXT(TAILQ_FIRST(&block->sb_rules), por_entry))
                return (0);

#ifdef OPT_DEBUG
        printf("--- Superblock ---\n");
        TAILQ_FOREACH(por, &block->sb_rules, por_entry) {
                printf("  ");
                print_rule(pf, &por->por_rule, por->por_rule.anchor ?
                    por->por_rule.anchor->name : "", PF_OPT_DEBUG);
        }
#endif /* OPT_DEBUG */


        if (remove_identical_rules(pf, block))
                return (1);
        if (combine_rules(pf, block))
                return (1);
        if ((pf->optimize & PF_OPTIMIZE_PROFILE) &&
            TAILQ_FIRST(&block->sb_rules)->por_rule.quick &&
            block->sb_profiled_block) {
                if (block_feedback(pf, block))
                        return (1);
        } else if (reorder_rules(pf, block, 0)) {
                return (1);
        }

        /*
         * Don't add any optimization passes below reorder_rules().  It will
         * have divided superblocks into smaller blocks for further refinement
         * and doesn't put them back together again.  What once was a true
         * superblock might have been split into multiple superblocks.
         */

#ifdef OPT_DEBUG
        printf("--- END Superblock ---\n");
#endif /* OPT_DEBUG */
        return (0);
}


/*
 * Optimization pass #1: remove identical rules
 */
int
remove_identical_rules(struct pfctl *pf, struct superblock *block)
{
        struct pf_opt_rule *por1, *por2, *por_next, *por2_next;
        struct pf_rule a, a2, b, b2;

        for (por1 = TAILQ_FIRST(&block->sb_rules); por1; por1 = por_next) {
                por_next = TAILQ_NEXT(por1, por_entry);
                for (por2 = por_next; por2; por2 = por2_next) {
                        por2_next = TAILQ_NEXT(por2, por_entry);
                        comparable_rule(&a, &por1->por_rule, DC);
                        comparable_rule(&b, &por2->por_rule, DC);
                        memcpy(&a2, &a, sizeof(a2));
                        memcpy(&b2, &b, sizeof(b2));

                        exclude_supersets(&a, &b);
                        exclude_supersets(&b2, &a2);
                        if (memcmp(&a, &b, sizeof(a)) == 0) {
                                DEBUG("removing identical rule  nr%d = *nr%d*",
                                    por1->por_rule.nr, por2->por_rule.nr);
                                TAILQ_REMOVE(&block->sb_rules, por2, por_entry);
                                if (por_next == por2)
                                        por_next = TAILQ_NEXT(por1, por_entry);
                                free(por2);
                        } else if (memcmp(&a2, &b2, sizeof(a2)) == 0) {
                                DEBUG("removing identical rule  *nr%d* = nr%d",
                                    por1->por_rule.nr, por2->por_rule.nr);
                                TAILQ_REMOVE(&block->sb_rules, por1, por_entry);
                                free(por1);
                                break;
                        }
                }
        }

        return (0);
}


/*
 * Optimization pass #2: combine similar rules with different addresses
 * into a single rule and a table
 */
int
combine_rules(struct pfctl *pf, struct superblock *block)
{
        struct pf_opt_rule *p1, *p2, *por_next;
        int src_eq, dst_eq;

        /* First we make a pass to combine the rules.  O(n log n) */
        TAILQ_FOREACH(p1, &block->sb_rules, por_entry) {
                for (p2 = TAILQ_NEXT(p1, por_entry); p2; p2 = por_next) {
                        por_next = TAILQ_NEXT(p2, por_entry);

                        src_eq = addrs_equal(&p1->por_rule.src,
                            &p2->por_rule.src);
                        dst_eq = addrs_equal(&p1->por_rule.dst,
                            &p2->por_rule.dst);

                        if (src_eq && !dst_eq && p1->por_src_tbl == NULL &&
                            p2->por_dst_tbl == NULL &&
                            p2->por_src_tbl == NULL &&
                            rules_combineable(&p1->por_rule, &p2->por_rule) &&
                            addrs_combineable(&p1->por_rule.dst,
                            &p2->por_rule.dst)) {
                                DEBUG("can combine rules  nr%d = nr%d",
                                    p1->por_rule.nr, p2->por_rule.nr);
                                if (p1->por_dst_tbl == NULL &&
                                    add_opt_table(pf, &p1->por_dst_tbl,
                                    p1->por_rule.af, &p1->por_rule.dst, NULL))
                                        return (1);
                                if (add_opt_table(pf, &p1->por_dst_tbl,
                                    p1->por_rule.af, &p2->por_rule.dst, NULL))
                                        return (1);
                                if (p1->por_dst_tbl->pt_rulecount >=
                                    TABLE_THRESHOLD) {
                                        TAILQ_REMOVE(&block->sb_rules, p2,
                                            por_entry);
                                        free(p2);
                                } else
                                        p2->por_dst_tbl =
                                            pf_opt_table_ref(p1->por_dst_tbl);
                        } else if (!src_eq && dst_eq && p1->por_dst_tbl == NULL
                            && p2->por_src_tbl == NULL &&
                            p2->por_dst_tbl == NULL &&
                            rules_combineable(&p1->por_rule, &p2->por_rule) &&
                            addrs_combineable(&p1->por_rule.src,
                            &p2->por_rule.src)) {
                                DEBUG("can combine rules  nr%d = nr%d",
                                    p1->por_rule.nr, p2->por_rule.nr);
                                if (p1->por_src_tbl == NULL &&
                                    add_opt_table(pf, &p1->por_src_tbl,
                                    p1->por_rule.af, &p1->por_rule.src, NULL))
                                        return (1);
                                if (add_opt_table(pf, &p1->por_src_tbl,
                                    p1->por_rule.af, &p2->por_rule.src, NULL))
                                        return (1);
                                if (p1->por_src_tbl->pt_rulecount >=
                                    TABLE_THRESHOLD) {
                                        TAILQ_REMOVE(&block->sb_rules, p2,
                                            por_entry);
                                        free(p2);
                                } else
                                        p2->por_src_tbl =
                                            pf_opt_table_ref(p1->por_src_tbl);
                        }
                }
        }


        /*
         * Then we make a final pass to create a valid table name and
         * insert the name into the rules.
         * Convert translation/routing mapping pools to tables as well.
         */
        for (p1 = TAILQ_FIRST(&block->sb_rules); p1; p1 = por_next) {
                por_next = TAILQ_NEXT(p1, por_entry);
                assert(p1->por_src_tbl == NULL || p1->por_dst_tbl == NULL);

                if (p1->por_src_tbl && p1->por_src_tbl->pt_rulecount >=
                    TABLE_THRESHOLD) {
                        if (p1->por_src_tbl->pt_generated) {
                                /* This rule is included in a table */
                                TAILQ_REMOVE(&block->sb_rules, p1, por_entry);
                                free(p1);
                                continue;
                        }
                        p1->por_src_tbl->pt_generated = 1;

                        if ((pf->opts & PF_OPT_NOACTION) == 0 &&
                            pf_opt_create_table(pf, p1->por_src_tbl))
                                return (1);

                        pf->tdirty = 1;

                        if (pf->opts & PF_OPT_VERBOSE)
                                print_tabledef(p1->por_src_tbl->pt_name,
                                    PFR_TFLAG_CONST, 1,
                                    &p1->por_src_tbl->pt_nodes);

                        memset(&p1->por_rule.src.addr, 0,
                            sizeof(p1->por_rule.src.addr));
                        p1->por_rule.src.addr.type = PF_ADDR_TABLE;
                        strlcpy(p1->por_rule.src.addr.v.tblname,
                            p1->por_src_tbl->pt_name,
                            sizeof(p1->por_rule.src.addr.v.tblname));

                        pfr_buf_clear(p1->por_src_tbl->pt_buf);
                        free(p1->por_src_tbl->pt_buf);
                        p1->por_src_tbl->pt_buf = NULL;
                }
                if (p1->por_dst_tbl && p1->por_dst_tbl->pt_rulecount >=
                    TABLE_THRESHOLD) {
                        if (p1->por_dst_tbl->pt_generated) {
                                /* This rule is included in a table */
                                TAILQ_REMOVE(&block->sb_rules, p1, por_entry);
                                free(p1);
                                continue;
                        }
                        p1->por_dst_tbl->pt_generated = 1;

                        if ((pf->opts & PF_OPT_NOACTION) == 0 &&
                            pf_opt_create_table(pf, p1->por_dst_tbl))
                                return (1);
                        pf->tdirty = 1;

                        if (pf->opts & PF_OPT_VERBOSE)
                                print_tabledef(p1->por_dst_tbl->pt_name,
                                    PFR_TFLAG_CONST, 1,
                                    &p1->por_dst_tbl->pt_nodes);

                        memset(&p1->por_rule.dst.addr, 0,
                            sizeof(p1->por_rule.dst.addr));
                        p1->por_rule.dst.addr.type = PF_ADDR_TABLE;
                        strlcpy(p1->por_rule.dst.addr.v.tblname,
                            p1->por_dst_tbl->pt_name,
                            sizeof(p1->por_rule.dst.addr.v.tblname));

                        pfr_buf_clear(p1->por_dst_tbl->pt_buf);
                        free(p1->por_dst_tbl->pt_buf);
                        p1->por_dst_tbl->pt_buf = NULL;
                }
        }

        return (0);
}


/*
 * Optimization pass #3: re-order rules to improve skip steps
 */
int
reorder_rules(struct pfctl *pf, struct superblock *block, int depth)
{
        struct superblock *newblock;
        struct pf_skip_step *skiplist;
        struct pf_opt_rule *por;
        int i, largest, largest_list, rule_count = 0;
        TAILQ_HEAD( , pf_opt_rule) head;

        /*
         * Calculate the best-case skip steps.  We put each rule in a list
         * of other rules with common fields
         */
        for (i = 0; i < PF_SKIP_COUNT; i++) {
                TAILQ_FOREACH(por, &block->sb_rules, por_entry) {
                        TAILQ_FOREACH(skiplist, &block->sb_skipsteps[i],
                            ps_entry) {
                                if (skip_compare(i, skiplist, por) == 0)
                                        break;
                        }
                        if (skiplist == NULL) {
                                if ((skiplist = calloc(1, sizeof(*skiplist))) ==
                                    NULL)
                                        err(1, "calloc");
                                TAILQ_INIT(&skiplist->ps_rules);
                                TAILQ_INSERT_TAIL(&block->sb_skipsteps[i],
                                    skiplist, ps_entry);
                        }
                        skip_append(block, i, skiplist, por);
                }
        }

        TAILQ_FOREACH(por, &block->sb_rules, por_entry)
                rule_count++;

        /*
         * Now we're going to ignore any fields that are identical between
         * all of the rules in the superblock and those fields which differ
         * between every rule in the superblock.
         */
        largest = 0;
        for (i = 0; i < PF_SKIP_COUNT; i++) {
                skiplist = TAILQ_FIRST(&block->sb_skipsteps[i]);
                if (skiplist->ps_count == rule_count) {
                        DEBUG("(%d) original skipstep '%s' is all rules",
                            depth, skip_comparitors_names[i]);
                        skiplist->ps_count = 0;
                } else if (skiplist->ps_count == 1) {
                        skiplist->ps_count = 0;
                } else {
                        DEBUG("(%d) original skipstep '%s' largest jump is %d",
                            depth, skip_comparitors_names[i],
                            skiplist->ps_count);
                        if (skiplist->ps_count > largest)
                                largest = skiplist->ps_count;
                }
        }
        if (largest == 0) {
                /* Ugh.  There is NO commonality in the superblock on which
                 * optimize the skipsteps optimization.
                 */
                goto done;
        }

        /*
         * Now we're going to empty the superblock rule list and re-create
         * it based on a more optimal skipstep order.
         */
        TAILQ_INIT(&head);
        TAILQ_CONCAT(&head, &block->sb_rules, por_entry);

        while (!TAILQ_EMPTY(&head)) {
                largest = 1;

                /*
                 * Find the most useful skip steps remaining
                 */
                for (i = 0; i < PF_SKIP_COUNT; i++) {
                        skiplist = TAILQ_FIRST(&block->sb_skipsteps[i]);
                        if (skiplist->ps_count > largest) {
                                largest = skiplist->ps_count;
                                largest_list = i;
                        }
                }

                if (largest <= 1) {
                        /*
                         * Nothing useful left.  Leave remaining rules in order.
                         */
                        DEBUG("(%d) no more commonality for skip steps", depth);
                        TAILQ_CONCAT(&block->sb_rules, &head, por_entry);
                } else {
                        /*
                         * There is commonality.  Extract those common rules
                         * and place them in the ruleset adjacent to each
                         * other.
                         */
                        skiplist = TAILQ_FIRST(&block->sb_skipsteps[
                            largest_list]);
                        DEBUG("(%d) skipstep '%s' largest jump is %d @ #%d",
                            depth, skip_comparitors_names[largest_list],
                            largest, TAILQ_FIRST(&TAILQ_FIRST(&block->
                            sb_skipsteps [largest_list])->ps_rules)->
                            por_rule.nr);
                        TAILQ_REMOVE(&block->sb_skipsteps[largest_list],
                            skiplist, ps_entry);


                        /*
                         * There may be further commonality inside these
                         * rules.  So we'll split them off into they're own
                         * superblock and pass it back into the optimizer.
                         */
                        if (skiplist->ps_count > 2) {
                                if ((newblock = calloc(1, sizeof(*newblock)))
                                    == NULL) {
                                        warn("calloc");
                                        return (1);
                                }
                                TAILQ_INIT(&newblock->sb_rules);
                                for (i = 0; i < PF_SKIP_COUNT; i++)
                                        TAILQ_INIT(&newblock->sb_skipsteps[i]);
                                TAILQ_INSERT_BEFORE(block, newblock, sb_entry);
                                DEBUG("(%d) splitting off %d rules from superblock @ #%d",
                                    depth, skiplist->ps_count,
                                    TAILQ_FIRST(&skiplist->ps_rules)->
                                    por_rule.nr);
                        } else {
                                newblock = block;
                        }

                        while ((por = TAILQ_FIRST(&skiplist->ps_rules))) {
                                TAILQ_REMOVE(&head, por, por_entry);
                                TAILQ_REMOVE(&skiplist->ps_rules, por,
                                    por_skip_entry[largest_list]);
                                TAILQ_INSERT_TAIL(&newblock->sb_rules, por,
                                    por_entry);

                                /* Remove this rule from all other skiplists */
                                remove_from_skipsteps(&block->sb_skipsteps[
                                    largest_list], block, por, skiplist);
                        }
                        free(skiplist);
                        if (newblock != block)
                                if (reorder_rules(pf, newblock, depth + 1))
                                        return (1);
                }
        }

done:
        for (i = 0; i < PF_SKIP_COUNT; i++) {
                while ((skiplist = TAILQ_FIRST(&block->sb_skipsteps[i]))) {
                        TAILQ_REMOVE(&block->sb_skipsteps[i], skiplist,
                            ps_entry);
                        free(skiplist);
                }
        }

        return (0);
}


/*
 * Optimization pass #4: re-order 'quick' rules based on feedback from the
 * currently running ruleset
 */
int
block_feedback(struct pfctl *pf, struct superblock *block)
{
        TAILQ_HEAD( , pf_opt_rule) queue;
        struct pf_opt_rule *por1, *por2;
        struct pf_rule a, b;


        /*
         * Walk through all of the profiled superblock's rules and copy
         * the counters onto our rules.
         */
        TAILQ_FOREACH(por1, &block->sb_profiled_block->sb_rules, por_entry) {
                comparable_rule(&a, &por1->por_rule, DC);
                TAILQ_FOREACH(por2, &block->sb_rules, por_entry) {
                        if (por2->por_profile_count)
                                continue;
                        comparable_rule(&b, &por2->por_rule, DC);
                        if (memcmp(&a, &b, sizeof(a)) == 0) {
                                por2->por_profile_count =
                                    por1->por_rule.packets[0] +
                                    por1->por_rule.packets[1];
                                break;
                        }
                }
        }
        superblock_free(pf, block->sb_profiled_block);
        block->sb_profiled_block = NULL;

        /*
         * Now we pull all of the rules off the superblock and re-insert them
         * in sorted order.
         */

        TAILQ_INIT(&queue);
        TAILQ_CONCAT(&queue, &block->sb_rules, por_entry);

        while ((por1 = TAILQ_FIRST(&queue)) != NULL) {
                TAILQ_REMOVE(&queue, por1, por_entry);
/* XXX I should sort all of the unused rules based on skip steps */
                TAILQ_FOREACH(por2, &block->sb_rules, por_entry) {
                        if (por1->por_profile_count > por2->por_profile_count) {
                                TAILQ_INSERT_BEFORE(por2, por1, por_entry);
                                break;
                        }
                }
                if (por2 == NULL)
                        TAILQ_INSERT_TAIL(&block->sb_rules, por1, por_entry);
        }

        return (0);
}


/*
 * Load the current ruleset from the kernel and try to associate them with
 * the ruleset we're optimizing.
 */
int
load_feedback_profile(struct pfctl *pf, struct superblocks *superblocks)
{
        struct superblock *block, *blockcur;
        struct superblocks prof_superblocks;
        struct pf_opt_rule *por;
        struct pf_opt_queue queue;
        struct pfioc_rule pr;
        struct pf_rule a, b;
        int nr, mnr;

        TAILQ_INIT(&queue);
        TAILQ_INIT(&prof_superblocks);

        memset(&pr, 0, sizeof(pr));
        pr.rule.action = PF_PASS;
        if (ioctl(pf->dev, DIOCGETRULES, &pr) == -1) {
                warnx("%s", pf_strerror(errno));
                return (1);
        }
        mnr = pr.nr;

        DEBUG("Loading %d active rules for a feedback profile", mnr);
        for (nr = 0; nr < mnr; ++nr) {
                struct pf_ruleset *rs;
                if ((por = calloc(1, sizeof(*por))) == NULL) {
                        warn("calloc");
                        return (1);
                }
                pr.nr = nr;
                if (ioctl(pf->dev, DIOCGETRULE, &pr) == -1) {
                        warnx("%s", pf_strerror(errno));
                        free(por);
                        return (1);
                }
                memcpy(&por->por_rule, &pr.rule, sizeof(por->por_rule));
                rs = pf_find_or_create_ruleset(pr.anchor_call);
                por->por_rule.anchor = rs->anchor;
                TAILQ_INSERT_TAIL(&queue, por, por_entry);
        }

        if (construct_superblocks(pf, &queue, &prof_superblocks))
                return (1);


        /*
         * Now we try to associate the active ruleset's superblocks with
         * the superblocks we're compiling.
         */
        block = TAILQ_FIRST(superblocks);
        blockcur = TAILQ_FIRST(&prof_superblocks);
        while (block && blockcur) {
                comparable_rule(&a, &TAILQ_FIRST(&block->sb_rules)->por_rule,
                    BREAK);
                comparable_rule(&b, &TAILQ_FIRST(&blockcur->sb_rules)->por_rule,
                    BREAK);
                if (memcmp(&a, &b, sizeof(a)) == 0) {
                        /* The two superblocks lined up */
                        block->sb_profiled_block = blockcur;
                } else {
                        DEBUG("superblocks don't line up between #%d and #%d",
                            TAILQ_FIRST(&block->sb_rules)->por_rule.nr,
                            TAILQ_FIRST(&blockcur->sb_rules)->por_rule.nr);
                        break;
                }
                block = TAILQ_NEXT(block, sb_entry);
                blockcur = TAILQ_NEXT(blockcur, sb_entry);
        }



        /* Free any superblocks we couldn't link */
        while (blockcur) {
                block = TAILQ_NEXT(blockcur, sb_entry);
                superblock_free(pf, blockcur);
                blockcur = block;
        }
        return (0);
}


/*
 * Compare a rule to a skiplist to see if the rule is a member
 */
int
skip_compare(int skipnum, struct pf_skip_step *skiplist,
    struct pf_opt_rule *por)
{
        struct pf_rule *a, *b;
        if (skipnum >= PF_SKIP_COUNT || skipnum < 0)
                errx(1, "skip_compare() out of bounds");
        a = &por->por_rule;
        b = &TAILQ_FIRST(&skiplist->ps_rules)->por_rule;

        return ((skip_comparitors[skipnum])(a, b));
}


/*
 * Add a rule to a skiplist
 */
void
skip_append(struct superblock *superblock, int skipnum,
    struct pf_skip_step *skiplist, struct pf_opt_rule *por)
{
        struct pf_skip_step *prev;

        skiplist->ps_count++;
        TAILQ_INSERT_TAIL(&skiplist->ps_rules, por, por_skip_entry[skipnum]);

        /* Keep the list of skiplists sorted by whichever is larger */
        while ((prev = TAILQ_PREV(skiplist, skiplist, ps_entry)) &&
            prev->ps_count < skiplist->ps_count) {
                TAILQ_REMOVE(&superblock->sb_skipsteps[skipnum],
                    skiplist, ps_entry);
                TAILQ_INSERT_BEFORE(prev, skiplist, ps_entry);
        }
}


/*
 * Remove a rule from the other skiplist calculations.
 */
void
remove_from_skipsteps(struct skiplist *head, struct superblock *block,
    struct pf_opt_rule *por, struct pf_skip_step *active_list)
{
        struct pf_skip_step *sk, *next;
        struct pf_opt_rule *p2;
        int i, found;

        for (i = 0; i < PF_SKIP_COUNT; i++) {
                sk = TAILQ_FIRST(&block->sb_skipsteps[i]);
                if (sk == NULL || sk == active_list || sk->ps_count <= 1)
                        continue;
                found = 0;
                do {
                        TAILQ_FOREACH(p2, &sk->ps_rules, por_skip_entry[i])
                                if (p2 == por) {
                                        TAILQ_REMOVE(&sk->ps_rules, p2,
                                            por_skip_entry[i]);
                                        found = 1;
                                        sk->ps_count--;
                                        break;
                                }
                } while (!found && (sk = TAILQ_NEXT(sk, ps_entry)));
                if (found && sk) {
                        /* Does this change the sorting order? */
                        while ((next = TAILQ_NEXT(sk, ps_entry)) &&
                            next->ps_count > sk->ps_count) {
                                TAILQ_REMOVE(head, sk, ps_entry);
                                TAILQ_INSERT_AFTER(head, next, sk, ps_entry);
                        }
#ifdef OPT_DEBUG
                        next = TAILQ_NEXT(sk, ps_entry);
                        assert(next == NULL || next->ps_count <= sk->ps_count);
#endif /* OPT_DEBUG */
                }
        }
}


/* Compare two rules AF field for skiplist construction */
int
skip_cmp_af(struct pf_rule *a, struct pf_rule *b)
{
        if (a->af != b->af || a->af == 0)
                return (1);
        return (0);
}

/* Compare two rules DIRECTION field for skiplist construction */
int
skip_cmp_dir(struct pf_rule *a, struct pf_rule *b)
{
        if (a->direction == 0 || a->direction != b->direction)
                return (1);
        return (0);
}

/* Compare two rules ON RDOMAIN field for skiplist construction */
int
skip_cmp_rdom(struct pf_rule *a, struct pf_rule *b)
{
        if (a->onrdomain == -1 || a->onrdomain != b->onrdomain)
                return (1);
        return (a->ifnot != b->ifnot);
}

/* Compare two rules DST Address field for skiplist construction */
int
skip_cmp_dst_addr(struct pf_rule *a, struct pf_rule *b)
{
        if (a->dst.neg != b->dst.neg ||
            a->dst.addr.type != b->dst.addr.type)
                return (1);
        /* XXX if (a->proto != b->proto && a->proto != 0 && b->proto != 0
         *    && (a->proto == IPPROTO_TCP || a->proto == IPPROTO_UDP ||
         *    a->proto == IPPROTO_ICMP
         *      return (1);
         */
        switch (a->dst.addr.type) {
        case PF_ADDR_ADDRMASK:
                if (memcmp(&a->dst.addr.v.a.addr, &b->dst.addr.v.a.addr,
                    sizeof(a->dst.addr.v.a.addr)) ||
                    memcmp(&a->dst.addr.v.a.mask, &b->dst.addr.v.a.mask,
                    sizeof(a->dst.addr.v.a.mask)) ||
                    (a->dst.addr.v.a.addr.addr32[0] == 0 &&
                    a->dst.addr.v.a.addr.addr32[1] == 0 &&
                    a->dst.addr.v.a.addr.addr32[2] == 0 &&
                    a->dst.addr.v.a.addr.addr32[3] == 0))
                        return (1);
                return (0);
        case PF_ADDR_DYNIFTL:
                if (strcmp(a->dst.addr.v.ifname, b->dst.addr.v.ifname) != 0 ||
                    a->dst.addr.iflags != b->dst.addr.iflags ||
                    memcmp(&a->dst.addr.v.a.mask, &b->dst.addr.v.a.mask,
                    sizeof(a->dst.addr.v.a.mask)))
                        return (1);
                return (0);
        case PF_ADDR_NOROUTE:
        case PF_ADDR_URPFFAILED:
                return (0);
        case PF_ADDR_TABLE:
                return (strcmp(a->dst.addr.v.tblname, b->dst.addr.v.tblname));
        }
        return (1);
}

/* Compare two rules DST port field for skiplist construction */
int
skip_cmp_dst_port(struct pf_rule *a, struct pf_rule *b)
{
        /* XXX if (a->proto != b->proto && a->proto != 0 && b->proto != 0
         *    && (a->proto == IPPROTO_TCP || a->proto == IPPROTO_UDP ||
         *    a->proto == IPPROTO_ICMP
         *      return (1);
         */
        if (a->dst.port_op == PF_OP_NONE || a->dst.port_op != b->dst.port_op ||
            a->dst.port[0] != b->dst.port[0] ||
            a->dst.port[1] != b->dst.port[1])
                return (1);
        return (0);
}

/* Compare two rules IFP field for skiplist construction */
int
skip_cmp_ifp(struct pf_rule *a, struct pf_rule *b)
{
        if (strcmp(a->ifname, b->ifname) || a->ifname[0] == '\0')
                return (1);
        return (a->ifnot != b->ifnot);
}

/* Compare two rules PROTO field for skiplist construction */
int
skip_cmp_proto(struct pf_rule *a, struct pf_rule *b)
{
        return (a->proto != b->proto || a->proto == 0);
}

/* Compare two rules SRC addr field for skiplist construction */
int
skip_cmp_src_addr(struct pf_rule *a, struct pf_rule *b)
{
        if (a->src.neg != b->src.neg ||
            a->src.addr.type != b->src.addr.type)
                return (1);
        /* XXX if (a->proto != b->proto && a->proto != 0 && b->proto != 0
         *    && (a->proto == IPPROTO_TCP || a->proto == IPPROTO_UDP ||
         *    a->proto == IPPROTO_ICMP
         *      return (1);
         */
        switch (a->src.addr.type) {
        case PF_ADDR_ADDRMASK:
                if (memcmp(&a->src.addr.v.a.addr, &b->src.addr.v.a.addr,
                    sizeof(a->src.addr.v.a.addr)) ||
                    memcmp(&a->src.addr.v.a.mask, &b->src.addr.v.a.mask,
                    sizeof(a->src.addr.v.a.mask)) ||
                    (a->src.addr.v.a.addr.addr32[0] == 0 &&
                    a->src.addr.v.a.addr.addr32[1] == 0 &&
                    a->src.addr.v.a.addr.addr32[2] == 0 &&
                    a->src.addr.v.a.addr.addr32[3] == 0))
                        return (1);
                return (0);
        case PF_ADDR_DYNIFTL:
                if (strcmp(a->src.addr.v.ifname, b->src.addr.v.ifname) != 0 ||
                    a->src.addr.iflags != b->src.addr.iflags ||
                    memcmp(&a->src.addr.v.a.mask, &b->src.addr.v.a.mask,
                    sizeof(a->src.addr.v.a.mask)))
                        return (1);
                return (0);
        case PF_ADDR_NOROUTE:
        case PF_ADDR_URPFFAILED:
                return (0);
        case PF_ADDR_TABLE:
                return (strcmp(a->src.addr.v.tblname, b->src.addr.v.tblname));
        }
        return (1);
}

/* Compare two rules SRC port field for skiplist construction */
int
skip_cmp_src_port(struct pf_rule *a, struct pf_rule *b)
{
        if (a->src.port_op == PF_OP_NONE || a->src.port_op != b->src.port_op ||
            a->src.port[0] != b->src.port[0] ||
            a->src.port[1] != b->src.port[1])
                return (1);
        /* XXX if (a->proto != b->proto && a->proto != 0 && b->proto != 0
         *    && (a->proto == IPPROTO_TCP || a->proto == IPPROTO_UDP ||
         *    a->proto == IPPROTO_ICMP
         *      return (1);
         */
        return (0);
}


void
skip_init(void)
{
        struct {
                char *name;
                int skipnum;
                int (*func)(struct pf_rule *, struct pf_rule *);
        } comps[] = PF_SKIP_COMPARITORS;
        int skipnum, i;

        for (skipnum = 0; skipnum < PF_SKIP_COUNT; skipnum++) {
                for (i = 0; i < sizeof(comps)/sizeof(*comps); i++)
                        if (comps[i].skipnum == skipnum) {
                                skip_comparitors[skipnum] = comps[i].func;
                                skip_comparitors_names[skipnum] = comps[i].name;
                        }
        }
        for (skipnum = 0; skipnum < PF_SKIP_COUNT; skipnum++)
                if (skip_comparitors[skipnum] == NULL)
                        errx(1, "Need to add skip step comparitor to pfctl?!");
}

/*
 * Add a host/netmask to a table
 */
int
add_opt_table(struct pfctl *pf, struct pf_opt_tbl **tbl, sa_family_t af,
    struct pf_rule_addr *addr, char *ifname)
{
#ifdef OPT_DEBUG
        char buf[128];
#endif /* OPT_DEBUG */
        static int tablenum = 0;
        struct node_host node_host;

        if (*tbl == NULL) {
                if ((*tbl = calloc(1, sizeof(**tbl))) == NULL ||
                    ((*tbl)->pt_buf = calloc(1, sizeof(*(*tbl)->pt_buf))) ==
                    NULL)
                        err(1, "calloc");
                (*tbl)->pt_refcnt = 1;
                (*tbl)->pt_buf->pfrb_type = PFRB_ADDRS;
                SIMPLEQ_INIT(&(*tbl)->pt_nodes);

                /* This is just a temporary table name */
                snprintf((*tbl)->pt_name, sizeof((*tbl)->pt_name), "%s%d",
                    PF_OPTIMIZER_TABLE_PFX, tablenum++);
                DEBUG("creating table <%s>", (*tbl)->pt_name);
        }

        memset(&node_host, 0, sizeof(node_host));
        node_host.af = af;
        node_host.addr = addr->addr;
        node_host.ifname = ifname;
        node_host.weight = addr->weight;

        DEBUG("<%s> adding %s/%d", (*tbl)->pt_name, inet_ntop(af,
            &node_host.addr.v.a.addr, buf, sizeof(buf)),
            unmask(&node_host.addr.v.a.mask));

        if (append_addr_host((*tbl)->pt_buf, &node_host, 0, 0)) {
                warn("failed to add host");
                return (1);
        }
        if (pf->opts & PF_OPT_VERBOSE) {
                struct node_tinit *ti;

                if ((ti = calloc(1, sizeof(*ti))) == NULL)
                        err(1, "malloc");
                if ((ti->host = malloc(sizeof(*ti->host))) == NULL)
                        err(1, "malloc");
                memcpy(ti->host, &node_host, sizeof(*ti->host));
                SIMPLEQ_INSERT_TAIL(&(*tbl)->pt_nodes, ti, entries);
        }

        (*tbl)->pt_rulecount++;
        if ((*tbl)->pt_rulecount == TABLE_THRESHOLD)
                DEBUG("table <%s> now faster than skip steps", (*tbl)->pt_name);

        return (0);
}


/*
 * Do the dirty work of choosing an unused table name and creating it.
 * (be careful with the table name, it might already be used in another anchor)
 */
int
pf_opt_create_table(struct pfctl *pf, struct pf_opt_tbl *tbl)
{
        static int tablenum;
        struct pfr_table *t;

        if (table_buffer.pfrb_type == 0) {
                /* Initialize the list of tables */
                table_buffer.pfrb_type = PFRB_TABLES;
                for (;;) {
                        pfr_buf_grow(&table_buffer, table_buffer.pfrb_size);
                        table_buffer.pfrb_size = table_buffer.pfrb_msize;
                        if (pfr_get_tables(NULL, table_buffer.pfrb_caddr,
                            &table_buffer.pfrb_size, PFR_FLAG_ALLRSETS))
                                err(1, "pfr_get_tables");
                        if (table_buffer.pfrb_size <= table_buffer.pfrb_msize)
                                break;
                }
                table_identifier = arc4random();
        }

        /* XXX would be *really* nice to avoid duplicating identical tables */

        /* Now we have to pick a table name that isn't used */
again:
        DEBUG("translating temporary table <%s> to <%s%x_%d>", tbl->pt_name,
            PF_OPTIMIZER_TABLE_PFX, table_identifier, tablenum);
        snprintf(tbl->pt_name, sizeof(tbl->pt_name), "%s%x_%d",
            PF_OPTIMIZER_TABLE_PFX, table_identifier, tablenum);
        PFRB_FOREACH(t, &table_buffer) {
                if (strcasecmp(t->pfrt_name, tbl->pt_name) == 0) {
                        /* Collision.  Try again */
                        DEBUG("wow, table <%s> in use.  trying again",
                            tbl->pt_name);
                        table_identifier = arc4random();
                        goto again;
                }
        }
        tablenum++;

        if (pfctl_define_table(tbl->pt_name, PFR_TFLAG_CONST | tbl->pt_flags, 1,
            pf->astack[0]->path, tbl->pt_buf, pf->astack[0]->ruleset.tticket,
            NULL)) {
                warn("failed to create table %s in %s",
                    tbl->pt_name, pf->astack[0]->name);
                return (1);
        }
        return (0);
}

/*
 * Partition the flat ruleset into a list of distinct superblocks
 */
int
construct_superblocks(struct pfctl *pf, struct pf_opt_queue *opt_queue,
    struct superblocks *superblocks)
{
        struct superblock *block = NULL;
        struct pf_opt_rule *por;
        int i;

        while (!TAILQ_EMPTY(opt_queue)) {
                por = TAILQ_FIRST(opt_queue);
                TAILQ_REMOVE(opt_queue, por, por_entry);
                if (block == NULL || !superblock_inclusive(block, por)) {
                        if ((block = calloc(1, sizeof(*block))) == NULL) {
                                warn("calloc");
                                return (1);
                        }
                        TAILQ_INIT(&block->sb_rules);
                        for (i = 0; i < PF_SKIP_COUNT; i++)
                                TAILQ_INIT(&block->sb_skipsteps[i]);
                        TAILQ_INSERT_TAIL(superblocks, block, sb_entry);
                }
                TAILQ_INSERT_TAIL(&block->sb_rules, por, por_entry);
        }

        return (0);
}


/*
 * Compare two rule addresses
 */
int
addrs_equal(struct pf_rule_addr *a, struct pf_rule_addr *b)
{
        if (a->neg != b->neg)
                return (0);
        return (memcmp(&a->addr, &b->addr, sizeof(a->addr)) == 0);
}


/*
 * The addresses are not equal, but can we combine them into one table?
 */
int
addrs_combineable(struct pf_rule_addr *a, struct pf_rule_addr *b)
{
        if (a->addr.type != PF_ADDR_ADDRMASK ||
            b->addr.type != PF_ADDR_ADDRMASK)
                return (0);
        if (a->neg != b->neg || a->port_op != b->port_op ||
            a->port[0] != b->port[0] || a->port[1] != b->port[1])
                return (0);
        return (1);
}


/*
 * Are we allowed to combine these two rules
 */
int
rules_combineable(struct pf_rule *p1, struct pf_rule *p2)
{
        struct pf_rule a, b;

        comparable_rule(&a, p1, COMBINED);
        comparable_rule(&b, p2, COMBINED);
        return (memcmp(&a, &b, sizeof(a)) == 0);
}


/*
 * Can a rule be included inside a superblock
 */
int
superblock_inclusive(struct superblock *block, struct pf_opt_rule *por)
{
        struct pf_rule a, b;
        int i, j;

        /* First check for hard breaks */
        for (i = 0; i < sizeof(pf_rule_desc)/sizeof(*pf_rule_desc); i++) {
                if (pf_rule_desc[i].prf_type == BARRIER) {
                        for (j = 0; j < pf_rule_desc[i].prf_size; j++)
                                if (((char *)&por->por_rule)[j +
                                    pf_rule_desc[i].prf_offset] != 0)
                                        return (0);
                }
        }

        /* per-rule src-track is also a hard break */
        if (por->por_rule.rule_flag & PFRULE_RULESRCTRACK)
                return (0);

        /*
         * Have to handle interface groups separately.  Consider the following
         * rules:
         *      block on EXTIFS to any port 22
         *      pass  on em0 to any port 22
         * (where EXTIFS is an arbitrary interface group)
         * The optimizer may decide to re-order the pass rule in front of the
         * block rule.  But what if EXTIFS includes em0???  Such a reordering
         * would change the meaning of the ruleset.
         * We can't just lookup the EXTIFS group and check if em0 is a member
         * because the user is allowed to add interfaces to a group during
         * runtime.
         * Ergo interface groups become a defacto superblock break :-(
         */
        if (interface_group(por->por_rule.ifname) ||
            interface_group(TAILQ_FIRST(&block->sb_rules)->por_rule.ifname)) {
                if (strcasecmp(por->por_rule.ifname,
                    TAILQ_FIRST(&block->sb_rules)->por_rule.ifname) != 0)
                        return (0);
        }

        comparable_rule(&a, &TAILQ_FIRST(&block->sb_rules)->por_rule, NOMERGE);
        comparable_rule(&b, &por->por_rule, NOMERGE);
        if (memcmp(&a, &b, sizeof(a)) == 0)
                return (1);

#ifdef OPT_DEBUG
        for (i = 0; i < sizeof(por->por_rule); i++) {
                int closest = -1;
                if (((u_int8_t *)&a)[i] != ((u_int8_t *)&b)[i]) {
                        for (j = 0; j < sizeof(pf_rule_desc) /
                            sizeof(*pf_rule_desc); j++) {
                                if (i >= pf_rule_desc[j].prf_offset &&
                                    i < pf_rule_desc[j].prf_offset +
                                    pf_rule_desc[j].prf_size) {
                                        DEBUG("superblock break @ %d due to %s",
                                            por->por_rule.nr,
                                            pf_rule_desc[j].prf_name);
                                        return (0);
                                }
                                if (i > pf_rule_desc[j].prf_offset) {
                                        if (closest == -1 ||
                                            i-pf_rule_desc[j].prf_offset <
                                            i-pf_rule_desc[closest].prf_offset)
                                                closest = j;
                                }
                        }

                        if (closest >= 0)
                                DEBUG("superblock break @ %d on %s+%lxh",
                                    por->por_rule.nr,
                                    pf_rule_desc[closest].prf_name,
                                    i - pf_rule_desc[closest].prf_offset -
                                    pf_rule_desc[closest].prf_size);
                        else
                                DEBUG("superblock break @ %d on field @ %d",
                                    por->por_rule.nr, i);
                        return (0);
                }
        }
#endif /* OPT_DEBUG */

        return (0);
}


/*
 * Figure out if an interface name is an actual interface or actually a
 * group of interfaces.
 */
int
interface_group(const char *ifname)
{
        if (ifname == NULL || !ifname[0])
                return (0);

        /* Real interfaces must end in a number, interface groups do not */
        if (isdigit((unsigned char)ifname[strlen(ifname) - 1]))
                return (0);
        else
                return (1);
}


/*
 * Make a rule that can directly compared by memcmp()
 */
void
comparable_rule(struct pf_rule *dst, const struct pf_rule *src, int type)
{
        int i;
        /*
         * To simplify the comparison, we just zero out the fields that are
         * allowed to be different and then do a simple memcmp()
         */
        memcpy(dst, src, sizeof(*dst));
        for (i = 0; i < sizeof(pf_rule_desc)/sizeof(*pf_rule_desc); i++)
                if (pf_rule_desc[i].prf_type >= type) {
#ifdef OPT_DEBUG
                        assert(pf_rule_desc[i].prf_type != NEVER ||
                            *(((char *)dst) + pf_rule_desc[i].prf_offset) == 0);
#endif /* OPT_DEBUG */
                        memset(((char *)dst) + pf_rule_desc[i].prf_offset, 0,
                            pf_rule_desc[i].prf_size);
                }
}


/*
 * Remove superset information from two rules so we can directly compare them
 * with memcmp()
 */
void
exclude_supersets(struct pf_rule *super, struct pf_rule *sub)
{
        if (super->ifname[0] == '\0')
                memset(sub->ifname, 0, sizeof(sub->ifname));
        if (super->direction == PF_INOUT)
                sub->direction = PF_INOUT;
        if ((super->proto == 0 || super->proto == sub->proto) &&
            super->flags == 0 && super->flagset == 0 && (sub->flags ||
            sub->flagset)) {
                sub->flags = super->flags;
                sub->flagset = super->flagset;
        }
        if (super->proto == 0)
                sub->proto = 0;

        if (super->src.port_op == 0) {
                sub->src.port_op = 0;
                sub->src.port[0] = 0;
                sub->src.port[1] = 0;
        }
        if (super->dst.port_op == 0) {
                sub->dst.port_op = 0;
                sub->dst.port[0] = 0;
                sub->dst.port[1] = 0;
        }

        if (super->src.addr.type == PF_ADDR_ADDRMASK && !super->src.neg &&
            !sub->src.neg && super->src.addr.v.a.mask.addr32[0] == 0 &&
            super->src.addr.v.a.mask.addr32[1] == 0 &&
            super->src.addr.v.a.mask.addr32[2] == 0 &&
            super->src.addr.v.a.mask.addr32[3] == 0)
                memset(&sub->src.addr, 0, sizeof(sub->src.addr));
        else if (super->src.addr.type == PF_ADDR_ADDRMASK &&
            sub->src.addr.type == PF_ADDR_ADDRMASK &&
            super->src.neg == sub->src.neg &&
            super->af == sub->af &&
            unmask(&super->src.addr.v.a.mask) <
            unmask(&sub->src.addr.v.a.mask) &&
            super->src.addr.v.a.addr.addr32[0] ==
            (sub->src.addr.v.a.addr.addr32[0] &
            super->src.addr.v.a.mask.addr32[0]) &&
            super->src.addr.v.a.addr.addr32[1] ==
            (sub->src.addr.v.a.addr.addr32[1] &
            super->src.addr.v.a.mask.addr32[1]) &&
            super->src.addr.v.a.addr.addr32[2] ==
            (sub->src.addr.v.a.addr.addr32[2] &
            super->src.addr.v.a.mask.addr32[2]) &&
            super->src.addr.v.a.addr.addr32[3] ==
            (sub->src.addr.v.a.addr.addr32[3] &
            super->src.addr.v.a.mask.addr32[3])) {
                /* sub->src.addr is a subset of super->src.addr/mask */
                memcpy(&sub->src.addr, &super->src.addr, sizeof(sub->src.addr));
        }

        if (super->dst.addr.type == PF_ADDR_ADDRMASK && !super->dst.neg &&
            !sub->dst.neg && super->dst.addr.v.a.mask.addr32[0] == 0 &&
            super->dst.addr.v.a.mask.addr32[1] == 0 &&
            super->dst.addr.v.a.mask.addr32[2] == 0 &&
            super->dst.addr.v.a.mask.addr32[3] == 0)
                memset(&sub->dst.addr, 0, sizeof(sub->dst.addr));
        else if (super->dst.addr.type == PF_ADDR_ADDRMASK &&
            sub->dst.addr.type == PF_ADDR_ADDRMASK &&
            super->dst.neg == sub->dst.neg &&
            super->af == sub->af &&
            unmask(&super->dst.addr.v.a.mask) <
            unmask(&sub->dst.addr.v.a.mask) &&
            super->dst.addr.v.a.addr.addr32[0] ==
            (sub->dst.addr.v.a.addr.addr32[0] &
            super->dst.addr.v.a.mask.addr32[0]) &&
            super->dst.addr.v.a.addr.addr32[1] ==
            (sub->dst.addr.v.a.addr.addr32[1] &
            super->dst.addr.v.a.mask.addr32[1]) &&
            super->dst.addr.v.a.addr.addr32[2] ==
            (sub->dst.addr.v.a.addr.addr32[2] &
            super->dst.addr.v.a.mask.addr32[2]) &&
            super->dst.addr.v.a.addr.addr32[3] ==
            (sub->dst.addr.v.a.addr.addr32[3] &
            super->dst.addr.v.a.mask.addr32[3])) {
                /* sub->dst.addr is a subset of super->dst.addr/mask */
                memcpy(&sub->dst.addr, &super->dst.addr, sizeof(sub->dst.addr));
        }

        if (super->af == 0)
                sub->af = 0;
}


void
superblock_free(struct pfctl *pf, struct superblock *block)
{
        struct pf_opt_rule *por;
        while ((por = TAILQ_FIRST(&block->sb_rules))) {
                TAILQ_REMOVE(&block->sb_rules, por, por_entry);
                pf_opt_table_unref(por->por_src_tbl);
                pf_opt_table_unref(por->por_dst_tbl);
                free(por);
        }
        if (block->sb_profiled_block)
                superblock_free(pf, block->sb_profiled_block);
        free(block);
}

struct  pf_opt_tbl *
pf_opt_table_ref(struct pf_opt_tbl *pt)
{
        /* parser does not run concurrently, we don't need atomic ops. */
        if (pt != NULL)
                pt->pt_refcnt++;

        return (pt);
}

void
pf_opt_table_unref(struct pf_opt_tbl *pt)
{
        if ((pt != NULL) && ((--pt->pt_refcnt) == 0)) {
                if (pt->pt_buf != NULL) {
                        pfr_buf_clear(pt->pt_buf);
                        free(pt->pt_buf);
                }
                free(pt);
        }
}