/*-
 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
 *
 * Copyright (c) 2006 Max Laier. 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.
 *
 * 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.
 *
 * $FreeBSD: head/sbin/ifconfig/ifgroup.c 326276 2017-11-27 15:37:16Z pfg $
 */

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

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

#include "ifconfig.h"

static void
setifgroup(const char *group_name, int d __unused, int s,
           const struct afswtch *rafp __unused)
{
        struct ifgroupreq ifgr;

        memset(&ifgr, 0, sizeof(ifgr));
        strlcpy(ifgr.ifgr_name, IfName, sizeof(ifgr.ifgr_name));

        if (group_name[0] && isdigit(group_name[strlen(group_name) - 1]))
                errx(1, "setifgroup: group names may not end in a digit");

        if (strlcpy(ifgr.ifgr_group, group_name, IFNAMSIZ) >= IFNAMSIZ)
                errx(1, "setifgroup: group name too long");
        if (ioctl(s, SIOCAIFGROUP, &ifgr) == -1 && errno != EEXIST)
                err(1," SIOCAIFGROUP");
}

static void
unsetifgroup(const char *group_name, int d __unused, int s,
             const struct afswtch *rafp __unused)
{
        struct ifgroupreq ifgr;

        memset(&ifgr, 0, sizeof(ifgr));
        strlcpy(ifgr.ifgr_name, IfName, sizeof(ifgr.ifgr_name));

        if (group_name[0] && isdigit(group_name[strlen(group_name) - 1]))
                errx(1, "unsetifgroup: group names may not end in a digit");

        if (strlcpy(ifgr.ifgr_group, group_name, IFNAMSIZ) >= IFNAMSIZ)
                errx(1, "unsetifgroup: group name too long");
        if (ioctl(s, SIOCDIFGROUP, &ifgr) == -1 && errno != ENOENT)
                err(1, "SIOCDIFGROUP");
}

static void
getifgroups(int s)
{
        struct ifgroupreq        ifgr;
        struct ifg_req          *ifg;
        size_t                   len, cnt;

        memset(&ifgr, 0, sizeof(ifgr));
        strlcpy(ifgr.ifgr_name, IfName, sizeof(ifgr.ifgr_name));

        if (ioctl(s, SIOCGIFGROUP, &ifgr) == -1) {
                if (errno == EINVAL || errno == ENOTTY)
                        return;
                else
                        err(1, "SIOCGIFGROUP");
        }

        len = ifgr.ifgr_len;
        ifgr.ifgr_groups = calloc(1, len);
        if (ifgr.ifgr_groups == NULL)
                err(1, "getifgroups");
        if (ioctl(s, SIOCGIFGROUP, &ifgr) == -1)
                err(1, "SIOCGIFGROUP");

        cnt = 0;
        ifg = ifgr.ifgr_groups;
        for (; ifg && len >= sizeof(struct ifg_req); ifg++) {
                len -= sizeof(struct ifg_req);
                if (strcmp(ifg->ifgrq_group, "all") != 0) {
                        if (cnt == 0)
                                printf("\tgroups:");
                        cnt++;
                        printf(" %s", ifg->ifgrq_group);
                }
        }
        if (cnt)
                printf("\n");

        free(ifgr.ifgr_groups);
}

static void
printgroup(const char *groupname)
{
        struct ifgroupreq        ifgr;
        struct ifg_req          *ifg;
        size_t                   len;
        int                      s;

        s = socket(AF_LOCAL, SOCK_DGRAM, 0);
        if (s == -1)
                err(1, "socket(AF_LOCAL,SOCK_DGRAM)");

        memset(&ifgr, 0, sizeof(ifgr));
        strlcpy(ifgr.ifgr_name, groupname, sizeof(ifgr.ifgr_name));
        if (ioctl(s, SIOCGIFGMEMB, &ifgr) == -1) {
                if (errno == EINVAL || errno == ENOTTY || errno == ENOENT)
                        exit(exit_code);
                else
                        err(1, "SIOCGIFGMEMB");
        }

        len = ifgr.ifgr_len;
        if ((ifgr.ifgr_groups = calloc(1, len)) == NULL)
                err(1, "printgroup");
        if (ioctl(s, SIOCGIFGMEMB, &ifgr) == -1)
                err(1, "SIOCGIFGMEMB");

        for (ifg = ifgr.ifgr_groups;
             ifg && len >= sizeof(struct ifg_req);
             ifg++) {
                len -= sizeof(struct ifg_req);
                printf("%s\n", ifg->ifgrq_member);
        }
        free(ifgr.ifgr_groups);

        exit(exit_code);
}

static struct cmd group_cmds[] = {
        DEF_CMD_ARG("group",    setifgroup),
        DEF_CMD_ARG("-group",   unsetifgroup),
};
static struct afswtch af_group = {
        .af_name                = "af_group",
        .af_af                  = AF_UNSPEC,
        .af_other_status        = getifgroups,
};
static struct option group_gopt = { "g:", "[-g groupname]", printgroup, NULL };

__constructor(132)
static void
group_ctor(void)
{
        size_t i;

        for (i = 0; i < nitems(group_cmds);  i++)
                cmd_register(&group_cmds[i]);

        af_register(&af_group);
        opt_register(&group_gopt);
}