/*-
 * SPDX-License-Identifier: BSD-3-Clause
 *
 * Copyright (c) 1983, 1993
 *      The Regents of the University of California.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#include <sys/param.h>
#include <sys/ioctl.h>
#include <sys/queue.h>
#include <sys/socket.h>
#include <net/if.h>

#include <err.h>
#include <libifconfig.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>

#include "ifconfig.h"

typedef enum {
        MT_PREFIX,
        MT_FILTER,
} clone_match_type;

static void
list_cloners(void)
{
        char *cloners;
        size_t cloners_count;

        if (ifconfig_list_cloners(lifh, &cloners, &cloners_count) < 0)
                errc(1, ifconfig_err_errno(lifh), "unable to list cloners");

        for (const char *name = cloners;
            name < cloners + cloners_count * IFNAMSIZ;
            name += IFNAMSIZ) {
                if (name > cloners)
                        putchar(' ');
                printf("%s", name);
        }
        putchar('\n');
        free(cloners);
}

struct clone_defcb {
        union {
                char ifprefix[IFNAMSIZ];
                clone_match_func *ifmatch;
        };
        clone_match_type clone_mt;
        clone_callback_func *clone_cb;
        SLIST_ENTRY(clone_defcb) next;
};

static SLIST_HEAD(, clone_defcb) clone_defcbh =
   SLIST_HEAD_INITIALIZER(clone_defcbh);

void
clone_setdefcallback_prefix(const char *ifprefix, clone_callback_func *p)
{
        struct clone_defcb *dcp;

        dcp = malloc(sizeof(*dcp));
        strlcpy(dcp->ifprefix, ifprefix, IFNAMSIZ-1);
        dcp->clone_mt = MT_PREFIX;
        dcp->clone_cb = p;
        SLIST_INSERT_HEAD(&clone_defcbh, dcp, next);
}

void
clone_setdefcallback_filter(clone_match_func *filter, clone_callback_func *p)
{
        struct clone_defcb *dcp;

        dcp = malloc(sizeof(*dcp));
        dcp->ifmatch  = filter;
        dcp->clone_mt = MT_FILTER;
        dcp->clone_cb = p;
        SLIST_INSERT_HEAD(&clone_defcbh, dcp, next);
}

/*
 * Do the actual clone operation.  Any parameters must have been
 * setup by now.  If a callback has been setup to do the work
 * then defer to it; otherwise do a simple create operation with
 * no parameters.
 */
static void
ifclonecreate(if_ctx *ctx, void *arg __unused)
{
        struct ifreq ifr = {};
        struct clone_defcb *dcp;
        u_int u;

        /* Warning to be removed in FreeBSD 17.0 */
        if (sscanf(ctx->ifname, "ipfw%u", &u) == 1 ||
            sscanf(ctx->ifname, "ipfwlog%u", &u) == 1) {
                warnx("ipfw(4) logging does not need interface creation "
                     "in FreeBSD 16.0");
                return;
        }
        if (sscanf(ctx->ifname, "pflog%u", &u) == 1) {
                warnx("pflog(4) logging does not need interface creation "
                     "in FreeBSD 16.0");
                return;
        }

        strlcpy(ifr.ifr_name, ctx->ifname, sizeof(ifr.ifr_name));

        /* Try to find a default callback by filter */
        SLIST_FOREACH(dcp, &clone_defcbh, next) {
                if (dcp->clone_mt == MT_FILTER &&
                    dcp->ifmatch(ifr.ifr_name) != 0)
                        break;
        }

        if (dcp == NULL) {
                /* Try to find a default callback by prefix */
                SLIST_FOREACH(dcp, &clone_defcbh, next) {
                        if (dcp->clone_mt == MT_PREFIX &&
                            strncmp(dcp->ifprefix, ifr.ifr_name,
                            strlen(dcp->ifprefix)) == 0)
                                break;
                }
        }

        if (dcp == NULL || dcp->clone_cb == NULL) {
                /* NB: no parameters */
                ifcreate_ioctl(ctx, &ifr);
        } else {
                dcp->clone_cb(ctx, &ifr);
        }
}

static void
clone_create(if_ctx *ctx __unused, const char *cmd __unused, int d __unused)
{
        callback_register(ifclonecreate, NULL);
}

static void
clone_destroy(if_ctx *ctx, const char *cmd __unused, int d __unused)
{
        struct ifreq ifr = {};

        if (ioctl_ctx_ifr(ctx, SIOCIFDESTROY, &ifr) < 0)
                err(1, "SIOCIFDESTROY");
}

static struct cmd clone_cmds[] = {
        DEF_CLONE_CMD("create", 0,      clone_create),
        DEF_CMD("destroy",      0,      clone_destroy),
        DEF_CLONE_CMD("plumb",  0,      clone_create),
        DEF_CMD("unplumb",      0,      clone_destroy),
};

static void
clone_Copt_cb(const char *arg __unused)
{
        list_cloners();
        exit(exit_code);
}
static struct option clone_Copt = { .opt = "C", .opt_usage = "[-C]", .cb = clone_Copt_cb };

static __constructor void
clone_ctor(void)
{
        size_t i;

        for (i = 0; i < nitems(clone_cmds);  i++)
                cmd_register(&clone_cmds[i]);
        opt_register(&clone_Copt);
}