/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (the "License").
 * You may not use this file except in compliance with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */

/*
 * Copyright (c) 2010, Oracle and/or its affiliates. All rights reserved.
 * Copyright 2021 Tintri by DDN, Inc. All rights reserved.
 */

#include <errno.h>
#include <sys/sockio.h>
#include <sys/list.h>
#include <string.h>
#include <assert.h>
#include <unistd.h>
#include <stropts.h>
#include <strings.h>
#include <libdlpi.h>
#include <libdllink.h>
#include <libinetutil.h>
#include <inet/ip.h>
#include <limits.h>
#include <zone.h>
#include <ipadm_ndpd.h>
#include <ipmp_query.h>
#include "libipadm_impl.h"

static ipadm_status_t   i_ipadm_slifname_arp(char *, uint64_t, int);
static ipadm_status_t   i_ipadm_slifname(ipadm_handle_t, char *, char *,
                            uint64_t, int, uint32_t);
static ipadm_status_t   i_ipadm_create_ipmp_peer(ipadm_handle_t, char *,
                            sa_family_t);
static ipadm_status_t   i_ipadm_persist_if(ipadm_handle_t, const char *,
                            sa_family_t, uint32_t);
static ipadm_status_t   i_ipadm_allocate_ifinfo(ipadm_if_info_t **);
static ipadm_status_t   i_ipadm_get_db_if(ipadm_handle_t, const char *,
                            nvlist_t **);
static ipadm_status_t i_ipadm_nvl2ifinfo(nvlist_t *, ipadm_if_info_t **);
static ipadm_status_t i_ipadm_fill_cmembers(char *, ipadm_ipmp_members_t *);
static ipadm_status_t i_ipadm_fill_pmembers(nvlist_t *, ipadm_ipmp_members_t *);
static ipadm_status_t i_ipadm_add_persistent_if_info(ipadm_if_info_t *,
                    ipadm_if_info_t *);
static void i_ipadm_free_ipmp_members(ipadm_ipmp_members_t *);
static ipadm_status_t i_ipadm_persist_update_ipmp(ipadm_handle_t, const char *,
        const char *,
        ipadm_ipmp_op_t);
static ipadm_status_t i_ipadm_update_ipmp(ipadm_handle_t, const char *,
        const char *, uint32_t,
        ipadm_ipmp_op_t);

/*
 * Returns B_FALSE if the interface in `ifname' has at least one address that is
 * IFF_UP in the addresses in `ifa'.
 */
static boolean_t
i_ipadm_is_if_down(char *ifname, struct ifaddrs *ifa)
{
        struct ifaddrs  *ifap;
        char            cifname[LIFNAMSIZ];
        char            *sep;

        for (ifap = ifa; ifap != NULL; ifap = ifap->ifa_next) {
                (void) strlcpy(cifname, ifap->ifa_name, sizeof (cifname));
                if ((sep = strrchr(cifname, IPADM_LOGICAL_SEP)) != NULL)
                        *sep = '\0';
                /*
                 * If this condition is true, there is at least one
                 * address that is IFF_UP. So, we need to return B_FALSE.
                 */
                if (strcmp(cifname, ifname) == 0 &&
                    (ifap->ifa_flags & IFF_UP)) {
                        return (B_FALSE);
                }
        }
        /* We did not find any IFF_UP addresses. */
        return (B_TRUE);
}

/*
 * Retrieves the information for the interface `ifname' from active
 * config if `ifname' is specified and returns the result in the list `if_info'.
 * Otherwise, it retrieves the information for all the interfaces in
 * the active config and returns the result in the list `if_info'.
 */
static ipadm_status_t
i_ipadm_active_if_info(ipadm_handle_t iph, const char *ifname,
    ipadm_if_info_t **if_info, int64_t lifc_flags)
{
        struct lifreq   *buf;
        struct lifreq   *lifrp;
        struct lifreq   lifrl;
        ipadm_if_info_t *last = NULL;
        ipadm_if_info_t *ifp;
        int             s;
        int             n;
        int             numifs;
        ipadm_status_t  status = IPADM_SUCCESS;

        *if_info = NULL;
        /*
         * Get information for all interfaces.
         */
        if (getallifs(iph->iph_sock, 0, &buf, &numifs, lifc_flags) != 0)
                return (ipadm_errno2status(errno));

        lifrp = buf;
        for (n = 0; n < numifs; n++, lifrp++) {
                /* Skip interfaces with logical num != 0 */
                if (i_ipadm_get_lnum(lifrp->lifr_name) != 0)
                        continue;
                /*
                 * Skip the current interface if a specific `ifname' has
                 * been requested and current interface does not match
                 * `ifname'.
                 */
                if (ifname != NULL && strcmp(lifrp->lifr_name, ifname) != 0)
                        continue;
                /*
                 * Check if the interface already exists in our list.
                 * If it already exists, we need to update its flags.
                 */
                for (ifp = *if_info; ifp != NULL; ifp = ifp->ifi_next) {
                        if (strcmp(lifrp->lifr_name, ifp->ifi_name) == 0)
                                break;
                }
                if (ifp == NULL) {
                        if ((status =
                            i_ipadm_allocate_ifinfo(&ifp)) != IPADM_SUCCESS)
                                        break;

                        (void) strlcpy(ifp->ifi_name, lifrp->lifr_name,
                            sizeof (ifp->ifi_name));
                        /* Update the `ifi_next' pointer for this new node */
                        if (*if_info == NULL)
                                *if_info = ifp;
                        else
                                last->ifi_next = ifp;
                        last = ifp;
                }

                /*
                 * Retrieve the flags for the interface by doing a
                 * SIOCGLIFFLAGS to populate the `ifi_cflags' field.
                 */
                (void) strlcpy(lifrl.lifr_name,
                    lifrp->lifr_name, sizeof (lifrl.lifr_name));
                s = (lifrp->lifr_addr.ss_family == AF_INET) ?
                    iph->iph_sock : iph->iph_sock6;
                if (ioctl(s, SIOCGLIFFLAGS, (caddr_t)&lifrl) < 0)
                        continue;

                /* a regular interface by default */
                ifp->ifi_class = IPADM_IF_CLASS_REGULAR;

                if (lifrl.lifr_flags & IFF_BROADCAST)
                        ifp->ifi_cflags |= IFIF_BROADCAST;
                if (lifrl.lifr_flags & IFF_MULTICAST)
                        ifp->ifi_cflags |= IFIF_MULTICAST;
                if (lifrl.lifr_flags & IFF_POINTOPOINT)
                        ifp->ifi_cflags |= IFIF_POINTOPOINT;
                if (lifrl.lifr_flags & IFF_VIRTUAL) {
                        ifp->ifi_cflags |= IFIF_VIRTUAL;
                        ifp->ifi_class = IPADM_IF_CLASS_VIRTUAL;
                }
                if (lifrl.lifr_flags & IFF_IPMP) {
                        ifp->ifi_cflags |= IFIF_IPMP;
                        ifp->ifi_class = IPADM_IF_CLASS_IPMP;
                }
                if (lifrl.lifr_flags & IFF_STANDBY)
                        ifp->ifi_cflags |= IFIF_STANDBY;
                if (lifrl.lifr_flags & IFF_INACTIVE)
                        ifp->ifi_cflags |= IFIF_INACTIVE;
                if (lifrl.lifr_flags & IFF_VRRP)
                        ifp->ifi_cflags |= IFIF_VRRP;
                if (lifrl.lifr_flags & IFF_NOACCEPT)
                        ifp->ifi_cflags |= IFIF_NOACCEPT;
                if (lifrl.lifr_flags & IFF_IPV4)
                        ifp->ifi_cflags |= IFIF_IPV4;
                if (lifrl.lifr_flags & IFF_IPV6)
                        ifp->ifi_cflags |= IFIF_IPV6;
                if (lifrl.lifr_flags & IFF_L3PROTECT)
                        ifp->ifi_cflags |= IFIF_L3PROTECT;

                /*
                 * Retrieve active IPMP members. This may fail in in.mpathd if
                 * the IPMP interface has just been created with no members.
                 * Hence, ignore errors, cmembers will just be empty.
                 */
                if (ifp->ifi_class == IPADM_IF_CLASS_IPMP) {
                        if (ioctl(s, SIOCGLIFGROUPNAME, (caddr_t)&lifrl) == 0) {
                                (void) i_ipadm_fill_cmembers(
                                    lifrl.lifr_groupname,
                                    &ifp->ifi_ipmp_cmembers);
                        }
                }
        }
        free(buf);
        if (status != IPADM_SUCCESS) {
                ipadm_free_if_info(*if_info);
                *if_info = NULL;
        }
        return (status);
}

/*
 * Returns the interface information for `ifname' in `if_info' from persistent
 * config if `ifname' is non-null. Otherwise, it returns all the interfaces
 * from persistent config in `if_info'.
 */
static ipadm_status_t
i_ipadm_persist_if_info(ipadm_handle_t iph, const char *ifname,
    ipadm_if_info_t **if_info)
{
        ipadm_status_t  status = IPADM_SUCCESS;
        nvlist_t        *ifs_info_nvl;

        *if_info = NULL;

        if ((status = i_ipadm_get_db_if(iph,
            ifname, &ifs_info_nvl)) != IPADM_SUCCESS)
                return (status);

        assert(ifs_info_nvl != NULL);

        return (i_ipadm_nvl2ifinfo(ifs_info_nvl, if_info));
}

static ipadm_status_t
i_ipadm_nvl2ifinfo(nvlist_t *ifs_info_nvl, ipadm_if_info_t **if_info)
{
        ipadm_if_info_t *ific = NULL, *ifil = NULL;
        nvlist_t        *if_info_nvl;
        nvpair_t        *nvp;
        char            *strval;
        ipadm_status_t  status = IPADM_SUCCESS;
        uint16_t        *families;
        uint_t          nelem = 0;

        for (nvp = nvlist_next_nvpair(ifs_info_nvl, NULL); nvp != NULL;
            nvp = nvlist_next_nvpair(ifs_info_nvl, nvp)) {
                if (nvpair_value_nvlist(nvp, &if_info_nvl) != 0)
                        continue;

                status = i_ipadm_allocate_ifinfo(&ific);
                if (status != IPADM_SUCCESS) {
                        ipadm_free_if_info(*if_info);
                        break;
                }
                if (nvlist_lookup_string(if_info_nvl, IPADM_NVP_IFNAME,
                    &strval) != 0) {
                        ipadm_free_if_info(ific);
                        ific = NULL;
                        continue;
                }
                (void) strlcpy(ific->ifi_name, strval,
                    sizeof (ific->ifi_name));

                if (nvlist_lookup_uint16_array(if_info_nvl,
                    IPADM_NVP_FAMILIES, &families, &nelem) == 0) {
                        while (nelem-- > 0) {
                                if (families[nelem] == AF_INET)
                                        ific->ifi_pflags |= IFIF_IPV4;
                                else if (families[nelem] == AF_INET6)
                                        ific->ifi_pflags |= IFIF_IPV6;
                        }
                }

                if (nvlist_lookup_string(if_info_nvl,
                    IPADM_NVP_IFCLASS, &strval) == 0)
                        ific->ifi_class = atoi(strval);
                else
                        ific->ifi_class = IPADM_IF_CLASS_REGULAR;

                if (ific->ifi_class == IPADM_IF_CLASS_IPMP)
                        /* do not expect any failures there */
                        (void) i_ipadm_fill_pmembers(if_info_nvl,
                            &ific->ifi_ipmp_pmembers);

                if (*if_info == NULL)
                        *if_info = ific;
                else
                        ifil->ifi_next = ific;
                ifil = ific;
        }

        nvlist_free(ifs_info_nvl);
        return (status);
}

/*
 * Fill the ipadm_if_info_t->ifi_ipmp_pmembers by info from
 * ipadm DB
 */
static ipadm_status_t
i_ipadm_fill_pmembers(nvlist_t *if_info_nvl, ipadm_ipmp_members_t *pmembers)
{
        uint_t  nelem = 0;
        char    **members;
        ipadm_ipmp_member_t *ipmp_member;

        if (nvlist_lookup_string_array(if_info_nvl, IPADM_NVP_MIFNAMES,
            &members, &nelem) != 0)
                return (IPADM_SUCCESS);

        while (nelem-- > 0) {
                if ((ipmp_member = calloc(1,
                    sizeof (ipadm_ipmp_member_t))) == NULL)
                        return (ipadm_errno2status(errno));

                (void) strlcpy(ipmp_member->if_name, members[nelem],
                    sizeof (ipmp_member->if_name));
                list_insert_tail(pmembers, ipmp_member);
        }
        return (IPADM_SUCCESS);
}

/*
 * Fill the ipadm_if_info_t->ifi_ipmp_cmembers by info from
 * kernel (libipmp is used to retrieve the required info)
 */
static ipadm_status_t
i_ipadm_fill_cmembers(char *grname, ipadm_ipmp_members_t *cmembers)
{
        ipmp_handle_t ipmp_handle;
        ipmp_groupinfo_t *grinfo;
        ipmp_iflist_t *iflistp;
        ipadm_ipmp_member_t *ipmp_member;
        ipadm_status_t ipadm_status = IPADM_SUCCESS;
        int i;

        if (ipmp_open(&ipmp_handle) != IPMP_SUCCESS)
                return (IPADM_FAILURE);

        if (ipmp_getgroupinfo(ipmp_handle, grname, &grinfo) != IPMP_SUCCESS) {
                ipadm_status = IPADM_FAILURE;
                goto fail2;
        }

        iflistp = grinfo->gr_iflistp;
        for (i = 0; i < iflistp->il_nif; i++) {
                if ((ipmp_member = calloc(1,
                    sizeof (ipadm_ipmp_member_t))) == NULL) {
                        ipadm_status = ipadm_errno2status(errno);
                        goto fail1;
                }
                (void) strlcpy(ipmp_member->if_name, iflistp->il_ifs[i],
                    sizeof (ipmp_member->if_name));
                list_insert_tail(cmembers, ipmp_member);
        }

fail1:
        ipmp_freegroupinfo(grinfo);
fail2:
        ipmp_close(ipmp_handle);
        return (ipadm_status);
}

/*
 * Collects information for `ifname' if one is specified from both
 * active and persistent config in `if_info'. If no `ifname' is specified,
 * this returns all the interfaces in active and persistent config in
 * `if_info'.
 */
ipadm_status_t
i_ipadm_get_all_if_info(ipadm_handle_t iph, const char *ifname,
    ipadm_if_info_t **if_info, int64_t lifc_flags)
{
        ipadm_status_t  status;
        ipadm_if_info_t *aifinfo = NULL;
        ipadm_if_info_t *pifinfo = NULL;
        ipadm_if_info_t *aifp;
        ipadm_if_info_t *pifp;
        ipadm_if_info_t *last = NULL;
        struct ifaddrs  *ifa;
        struct ifaddrs  *ifap;

        /*
         * Retrive the information for the requested `ifname' or all
         * interfaces from active configuration.
         */
retry:
        status = i_ipadm_active_if_info(iph, ifname, &aifinfo, lifc_flags);
        if (status != IPADM_SUCCESS)
                return (status);
        /* Get the interface state for each interface in `aifinfo'. */
        if (aifinfo != NULL) {
                /* We need all addresses to get the interface state */
                if (getallifaddrs(AF_UNSPEC, &ifa, (LIFC_NOXMIT|LIFC_TEMPORARY|
                    LIFC_ALLZONES|LIFC_UNDER_IPMP)) != 0) {
                        status = ipadm_errno2status(errno);
                        goto fail;
                }
                for (aifp = aifinfo; aifp != NULL; aifp = aifp->ifi_next) {
                        /*
                         * Find the `ifaddrs' structure from `ifa'
                         * for this interface. We need the IFF_* flags
                         * to find the interface state.
                         */
                        for (ifap = ifa; ifap != NULL; ifap = ifap->ifa_next) {
                                if (ifap->ifa_addr->sa_family == AF_LINK)
                                        continue;
                                if (strcmp(ifap->ifa_name, aifp->ifi_name) == 0)
                                        break;
                        }
                        if (ifap == NULL) {
                                /*
                                 * The interface might have been removed
                                 * from kernel. Retry getting all the active
                                 * interfaces.
                                 */
                                freeifaddrs(ifa);
                                ipadm_free_if_info(aifinfo);
                                aifinfo = NULL;
                                goto retry;
                        }
                        if (!(ifap->ifa_flags & IFF_RUNNING) ||
                            (ifap->ifa_flags & IFF_FAILED))
                                aifp->ifi_state = IFIS_FAILED;
                        else if (ifap->ifa_flags & IFF_OFFLINE)
                                aifp->ifi_state = IFIS_OFFLINE;
                        else if (i_ipadm_is_if_down(aifp->ifi_name, ifa))
                                aifp->ifi_state = IFIS_DOWN;
                        else
                                aifp->ifi_state = IFIS_OK;
                        if (aifp->ifi_next == NULL)
                                last = aifp;
                }
                freeifaddrs(ifa);
        }
        /*
         * Get the persistent interface information in `pifinfo'.
         */
        status = i_ipadm_persist_if_info(iph, ifname, &pifinfo);
        if (status == IPADM_NOTFOUND) {
                *if_info = aifinfo;
                return (IPADM_SUCCESS);
        }
        if (status != IPADM_SUCCESS)
                goto fail;

        /*
         * Process the persistent interface information.
         *
         * First try to get the persistent "standby" property, as that isn't
         * retrieved by i_ipadm_persist_if_info().
         *
         * Next, if a persistent interface is also found in `aifinfo', update
         * its entry in `aifinfo' with the persistent information from
         * `pifinfo'. If an interface is found in `pifinfo', but not in
         * `aifinfo', it means that this interface was disabled. We should
         * add this interface to `aifinfo' and set it state to IFIF_DISABLED.
         */
        for (pifp = pifinfo; pifp != NULL; pifp = pifp->ifi_next) {
                char buf[10] = "";
                uint_t bufsize = sizeof (buf);

                status = ipadm_get_ifprop(iph, pifp->ifi_name, "standby", buf,
                    &bufsize, MOD_PROTO_IP, IPADM_OPT_PERSIST);

                if (status == IPADM_SUCCESS && strcmp(buf, "on") == 0)
                        pifp->ifi_pflags |= IFIF_STANDBY;

                for (aifp = aifinfo; aifp != NULL; aifp = aifp->ifi_next) {
                        if (strcmp(aifp->ifi_name, pifp->ifi_name) == 0) {
                                break;
                        }
                }

                if (aifp == NULL) {
                        if ((status =
                            i_ipadm_allocate_ifinfo(&aifp)) != IPADM_SUCCESS)
                                goto fail;

                        (void) strlcpy(aifp->ifi_name, pifp->ifi_name,
                            sizeof (aifp->ifi_name));

                        aifp->ifi_next = NULL;
                        aifp->ifi_state = IFIS_DISABLED;
                        if (last != NULL)
                                last->ifi_next = aifp;
                        else
                                aifinfo = aifp;
                        last = aifp;
                }

                if ((status = i_ipadm_add_persistent_if_info(aifp,
                    pifp)) != IPADM_SUCCESS)
                        goto fail;
        }
        *if_info = aifinfo;
        ipadm_free_if_info(pifinfo);
        return (IPADM_SUCCESS);
fail:
        *if_info = NULL;
        ipadm_free_if_info(aifinfo);
        ipadm_free_if_info(pifinfo);
        return (status);
}

/*
 * Updates active if_info by data from persistent if_info
 */
static ipadm_status_t
i_ipadm_add_persistent_if_info(ipadm_if_info_t *aifp, ipadm_if_info_t *pifp)
{
        ipadm_ipmp_member_t *pp_ipmp_member, *ap_ipmp_member;

        ipadm_ipmp_members_t *apmembers = &aifp->ifi_ipmp_pmembers;
        ipadm_ipmp_members_t *ppmembers = &pifp->ifi_ipmp_pmembers;

        aifp->ifi_pflags = pifp->ifi_pflags;
        aifp->ifi_class = pifp->ifi_class;

        for (pp_ipmp_member = list_head(ppmembers); pp_ipmp_member;
            pp_ipmp_member = list_next(ppmembers, pp_ipmp_member)) {
                if ((ap_ipmp_member = calloc(1,
                    sizeof (ipadm_ipmp_member_t))) == NULL)
                        return (ipadm_errno2status(errno));

                (void) strlcpy(ap_ipmp_member->if_name,
                    pp_ipmp_member->if_name,
                    sizeof (ap_ipmp_member->if_name));

                list_insert_tail(apmembers, ap_ipmp_member);
        }
        return (IPADM_SUCCESS);
}

static ipadm_status_t
i_ipadm_allocate_ifinfo(ipadm_if_info_t **if_info)
{
        *if_info = calloc(1, sizeof (ipadm_if_info_t));
        if (*if_info == NULL)
                return (ipadm_errno2status(errno));

        /* List of active (current) members */
        list_create(&((*if_info)->ifi_ipmp_cmembers),
            sizeof (ipadm_ipmp_member_t),
            offsetof(ipadm_ipmp_member_t, node));

        /* List of persistent members */
        list_create(&((*if_info)->ifi_ipmp_pmembers),
            sizeof (ipadm_ipmp_member_t),
            offsetof(ipadm_ipmp_member_t, node));

        return (IPADM_SUCCESS);
}

/*
 * Reads all the interface lines from the persistent DB into the nvlist `onvl',
 * when `ifname' is NULL.
 * If an `ifname' is specified, then the interface line corresponding to
 * that name will be returned.
 */
static ipadm_status_t
i_ipadm_get_db_if(ipadm_handle_t iph, const char *ifname, nvlist_t **onvl)
{
        ipmgmt_getif_arg_t      garg;

        /* Populate the door_call argument structure */
        bzero(&garg, sizeof (garg));
        garg.ia_cmd = IPMGMT_CMD_GETIF;
        if (ifname != NULL)
                (void) strlcpy(garg.ia_ifname, ifname, sizeof (garg.ia_ifname));

        return (i_ipadm_call_ipmgmtd(iph, (void *) &garg, sizeof (garg), onvl));
}

int
i_ipadm_get_lnum(const char *ifname)
{
        char *num = strrchr(ifname, IPADM_LOGICAL_SEP);

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

        return (atoi(++num));
}

/*
 * Sets the output argument `exists' to true or false based on whether
 * any persistent configuration is available for `ifname' and returns
 * IPADM_SUCCESS as status. If the persistent information cannot be retrieved,
 * `exists' is unmodified and an error status is returned.
 */
ipadm_status_t
i_ipadm_if_pexists(ipadm_handle_t iph, const char *ifname, sa_family_t af,
    boolean_t *exists)
{
        ipadm_if_info_t *ifinfo;
        ipadm_status_t  status;

        /*
         * if IPH_IPMGMTD is set, we know that the caller (ipmgmtd) already
         * knows about persistent configuration in the first place, so we
         * just return success.
         */
        if (iph->iph_flags & IPH_IPMGMTD) {
                *exists = B_FALSE;
                return (IPADM_SUCCESS);
        }
        status = i_ipadm_persist_if_info(iph, ifname, &ifinfo);
        if (status == IPADM_SUCCESS) {
                *exists = ((af == AF_INET &&
                    (ifinfo->ifi_pflags & IFIF_IPV4)) ||
                    (af == AF_INET6 &&
                    (ifinfo->ifi_pflags & IFIF_IPV6)));
                ipadm_free_if_info(ifinfo);
        } else if (status == IPADM_NOTFOUND) {
                status = IPADM_SUCCESS;
                *exists = B_FALSE;
        }
        return (status);
}

/*
 * Open "/dev/udp{,6}" for use as a multiplexor to PLINK the interface stream
 * under. We use "/dev/udp" instead of "/dev/ip" since STREAMS will not let
 * you PLINK a driver under itself, and "/dev/ip" is typically the driver at
 * the bottom of the stream for tunneling interfaces.
 */
ipadm_status_t
ipadm_open_arp_on_udp(const char *udp_dev_name, int *fd)
{
        int err;

        if ((*fd = open(udp_dev_name, O_RDWR)) == -1)
                return (ipadm_errno2status(errno));

        /*
         * Pop off all undesired modules (note that the user may have
         * configured autopush to add modules above udp), and push the
         * arp module onto the resulting stream. This is used to make
         * IP+ARP be able to atomically track the muxid for the I_PLINKed
         * STREAMS, thus it isn't related to ARP running the ARP protocol.
         */
        while (ioctl(*fd, I_POP, 0) != -1)
                ;
        if (errno == EINVAL && ioctl(*fd, I_PUSH, ARP_MOD_NAME) != -1)
                return (IPADM_SUCCESS);
        err = errno;
        (void) close(*fd);

        return (ipadm_errno2status(err));
}

/*
 * i_ipadm_create_ipmp() is called from i_ipadm_create_ipmp_peer() when an
 * underlying interface in an ipmp group G is plumbed for an address family,
 * but the meta-interface for the other address family `af' does not exist
 * yet for the group G. If `af' is IPv6, we need to bring up the
 * link-local address.
 */
static ipadm_status_t
i_ipadm_create_ipmp(ipadm_handle_t iph, char *ifname, sa_family_t af,
    const char *grname, uint32_t ipadm_flags)
{
        ipadm_status_t  status;
        struct lifreq   lifr;
        int             sock;
        int             err;

        assert(ipadm_flags & IPADM_OPT_IPMP);

        /* Create the ipmp underlying interface */
        status = i_ipadm_create_if(iph, ifname, af, ipadm_flags);
        if (status != IPADM_SUCCESS && status != IPADM_IF_EXISTS)
                return (status);

        /*
         * To preserve backward-compatibility, always bring up the link-local
         * address for implicitly-created IPv6 IPMP interfaces.
         */
        if (af == AF_INET6)
                (void) i_ipadm_set_flags(iph, ifname, AF_INET6, IFF_UP, 0);

        sock = (af == AF_INET ? iph->iph_sock : iph->iph_sock6);
        /*
         * If the caller requested a different group name, issue a
         * SIOCSLIFGROUPNAME on the new IPMP interface.
         */
        bzero(&lifr, sizeof (lifr));
        (void) strlcpy(lifr.lifr_name, ifname, sizeof (lifr.lifr_name));
        if (strcmp(lifr.lifr_name, grname) != 0) {
                (void) strlcpy(lifr.lifr_groupname, grname, LIFGRNAMSIZ);
                if (ioctl(sock, SIOCSLIFGROUPNAME, &lifr) == -1) {
                        err = errno;
                        /* Remove the interface we created. */
                        if (status == IPADM_SUCCESS) {
                                (void) i_ipadm_delete_if(iph, ifname, af,
                                    ipadm_flags);
                        }
                        return (ipadm_errno2status(err));
                }
        }

        return (IPADM_SUCCESS);
}

/*
 * Checks if `ifname' is plumbed and in an IPMP group on its "other" address
 * family.  If so, create a matching IPMP group for address family `af'.
 */
static ipadm_status_t
i_ipadm_create_ipmp_peer(ipadm_handle_t iph, char *ifname, sa_family_t af)
{
        lifgroupinfo_t  lifgr;
        ipadm_status_t  status = IPADM_SUCCESS;
        struct lifreq   lifr;
        int             other_af_sock;

        assert(af == AF_INET || af == AF_INET6);

        other_af_sock = (af == AF_INET ? iph->iph_sock6 : iph->iph_sock);

        /*
         * iph is the handle for the interface that we are trying to plumb.
         * other_af_sock is the socket for the "other" address family.
         */
        bzero(&lifr, sizeof (lifr));
        (void) strlcpy(lifr.lifr_name, ifname, sizeof (lifr.lifr_name));
        if (ioctl(other_af_sock, SIOCGLIFGROUPNAME, &lifr) != 0)
                return (IPADM_SUCCESS);

        (void) strlcpy(lifgr.gi_grname, lifr.lifr_groupname, LIFGRNAMSIZ);
        if (ioctl(other_af_sock, SIOCGLIFGROUPINFO, &lifgr) != 0)
                return (IPADM_SUCCESS);

        /*
         * If `ifname' *is* the IPMP group interface, or if the relevant
         * address family is already configured, then there's nothing to do.
         */
        if (strcmp(lifgr.gi_grifname, ifname) == 0 ||
            (af == AF_INET && lifgr.gi_v4) || (af == AF_INET6 && lifgr.gi_v6)) {
                return (IPADM_SUCCESS);
        }

        status = i_ipadm_create_ipmp(iph, lifgr.gi_grifname, af,
            lifgr.gi_grname, IPADM_OPT_ACTIVE|IPADM_OPT_IPMP);
        return (status);
}

/*
 * Issues the ioctl SIOCSLIFNAME to kernel on the given ARP stream fd.
 */
static ipadm_status_t
i_ipadm_slifname_arp(char *ifname, uint64_t flags, int fd)
{
        struct lifreq   lifr;
        ifspec_t        ifsp;

        bzero(&lifr, sizeof (lifr));
        (void) ifparse_ifspec(ifname, &ifsp);
        lifr.lifr_ppa = ifsp.ifsp_ppa;
        lifr.lifr_flags = flags;
        (void) strlcpy(lifr.lifr_name, ifname, sizeof (lifr.lifr_name));
        /*
         * Tell ARP the name and unit number for this interface.
         * Note that arp has no support for transparent ioctls.
         */
        if (i_ipadm_strioctl(fd, SIOCSLIFNAME, (char *)&lifr,
            sizeof (lifr)) == -1) {
                return (ipadm_errno2status(errno));
        }
        return (IPADM_SUCCESS);
}

/*
 * Issues the ioctl SIOCSLIFNAME to kernel. If IPADM_OPT_GENPPA is set in
 * `ipadm_flags', then a ppa will be generated. `newif' will be updated
 * with the generated ppa.
 */
static ipadm_status_t
i_ipadm_slifname(ipadm_handle_t iph, char *ifname, char *newif, uint64_t flags,
    int fd, uint32_t ipadm_flags)
{
        struct lifreq   lifr;
        ipadm_status_t  status = IPADM_SUCCESS;
        int             err = 0;
        sa_family_t     af;
        int             ppa;
        ifspec_t        ifsp;
        boolean_t       valid_if;

        bzero(&lifr, sizeof (lifr));
        if (ipadm_flags & IPADM_OPT_GENPPA) {
                /*
                 * We'd like to just set lifr_ppa to UINT_MAX and have the
                 * kernel pick a PPA.  Unfortunately, that would mishandle
                 * two cases:
                 *
                 *      1. If the PPA is available but the groupname is taken
                 *         (e.g., the "ipmp2" IP interface name is available
                 *         but the "ipmp2" groupname is taken) then the
                 *         auto-assignment by the kernel will fail.
                 *
                 *      2. If we're creating (e.g.) an IPv6-only IPMP
                 *         interface, and there's already an IPv4-only IPMP
                 *         interface, the kernel will allow us to accidentally
                 *         reuse the IPv6 IPMP interface name (since
                 *         SIOCSLIFNAME uniqueness is per-interface-type).
                 *         This will cause administrative confusion.
                 *
                 * Thus, we instead take a brute-force approach of checking
                 * whether the IPv4 or IPv6 name is already in-use before
                 * attempting the SIOCSLIFNAME.  As per (1) above, the
                 * SIOCSLIFNAME may still fail, in which case we just proceed
                 * to the next one.  If this approach becomes too slow, we
                 * can add a new SIOC* to handle this case in the kernel.
                 */
                for (ppa = 0; ppa < UINT_MAX; ppa++) {
                        (void) snprintf(lifr.lifr_name, LIFNAMSIZ, "%s%d",
                            ifname, ppa);

                        if (ioctl(iph->iph_sock, SIOCGLIFFLAGS, &lifr) != -1 ||
                            errno != ENXIO)
                                continue;

                        if (ioctl(iph->iph_sock6, SIOCGLIFFLAGS, &lifr) != -1 ||
                            errno != ENXIO)
                                continue;

                        lifr.lifr_ppa = ppa;
                        lifr.lifr_flags = flags;

                        err = ioctl(fd, SIOCSLIFNAME, &lifr);
                        if (err != -1 || errno != EEXIST)
                                break;
                }
                if (err == -1) {
                        status = ipadm_errno2status(errno);
                } else {
                        /*
                         * PPA has been successfully established.
                         * Update `newif' with the ppa.
                         */
                        assert(newif != NULL);
                        if (snprintf(newif, LIFNAMSIZ, "%s%d", ifname,
                            ppa) >= LIFNAMSIZ)
                                return (IPADM_INVALID_ARG);
                }
        } else {
                /* We should have already validated the interface name. */
                valid_if = ifparse_ifspec(ifname, &ifsp);
                assert(valid_if);

                /*
                 * Before we call SIOCSLIFNAME, ensure that the IPMP group
                 * interface for this address family exists.  Otherwise, the
                 * kernel will kick the interface out of the group when we do
                 * the SIOCSLIFNAME.
                 *
                 * Example: suppose bge0 is plumbed for IPv4 and in group "a".
                 * If we're now plumbing bge0 for IPv6, but the IPMP group
                 * interface for "a" is not plumbed for IPv6, the SIOCSLIFNAME
                 * will kick bge0 out of group "a", which is undesired.
                 */
                if (flags & IFF_IPV4)
                        af = AF_INET;
                else
                        af = AF_INET6;
                status = i_ipadm_create_ipmp_peer(iph, ifname, af);
                if (status != IPADM_SUCCESS)
                        return (status);
                lifr.lifr_ppa = ifsp.ifsp_ppa;
                lifr.lifr_flags = flags;
                (void) strlcpy(lifr.lifr_name, ifname, sizeof (lifr.lifr_name));
                if (ioctl(fd, SIOCSLIFNAME, &lifr) == -1)
                        status = ipadm_errno2status(errno);
        }

        return (status);
}

/*
 * Plumbs the interface `ifname' for the address family `af'. It also persists
 * the interface for `af' if IPADM_OPT_PERSIST is set in `ipadm_flags'.
 */
ipadm_status_t
i_ipadm_plumb_if(ipadm_handle_t iph, char *ifname, sa_family_t af,
    uint32_t ipadm_flags)
{
        int             ip_muxid;
        int             mux_fd = -1, ip_fd, arp_fd;
        char            *udp_dev_name;
        dlpi_handle_t   dh_arp = NULL, dh_ip;
        uint64_t        ifflags;
        struct lifreq   lifr;
        uint_t          dlpi_flags;
        ipadm_status_t  status = IPADM_SUCCESS;
        char            *linkname;
        boolean_t       legacy = (iph->iph_flags & IPH_LEGACY);
        zoneid_t        zoneid;
        char            newif[LIFNAMSIZ];
        char            lifname[LIFNAMSIZ];
        datalink_id_t   linkid;
        int             sock;
        boolean_t       islo;
        boolean_t       is_persistent =
            ((ipadm_flags & IPADM_OPT_PERSIST) != 0);
        uint32_t        dlflags;
        dladm_status_t  dlstatus;

        if (iph->iph_dlh != NULL) {
                dlstatus = dladm_name2info(iph->iph_dlh, ifname, &linkid,
                    &dlflags, NULL, NULL);
        }
        /*
         * If we're in the global zone and we're plumbing a datalink, make
         * sure that the datalink is not assigned to a non-global zone.  Note
         * that the non-global zones don't need this check, because zoneadm
         * has taken care of this when the zones boot.
         */
        if (iph->iph_zoneid == GLOBAL_ZONEID && dlstatus == DLADM_STATUS_OK) {
                zoneid = ALL_ZONES;
                if (zone_check_datalink(&zoneid, linkid) == 0) {
                        /* interface is in use by a non-global zone. */
                        return (IPADM_IF_INUSE);
                }
        }

        /* loopback interfaces are just added as logical interface */
        bzero(&lifr, sizeof (lifr));
        islo = i_ipadm_is_loopback(ifname);
        if (islo || i_ipadm_get_lnum(ifname) != 0) {
                (void) strlcpy(lifr.lifr_name, ifname, sizeof (lifr.lifr_name));
                if (af == AF_INET)
                        sock = iph->iph_sock;
                else
                        sock = iph->iph_sock6;
                if (islo && ioctl(sock, SIOCGLIFADDR, (caddr_t)&lifr) >= 0)
                        return (IPADM_IF_EXISTS);
                if (ioctl(sock, SIOCLIFADDIF, (caddr_t)&lifr) < 0)
                        return (ipadm_errno2status(errno));

                /*
                 * By default, kernel configures 127.0.0.1 on the loopback
                 * interface. Replace this with 0.0.0.0 to be consistent
                 * with interface creation on other physical interfaces.
                 */
                if (islo && !legacy) {
                        bzero(&lifr.lifr_addr, sizeof (lifr.lifr_addr));
                        lifr.lifr_addr.ss_family = af;
                        if (ioctl(sock, SIOCSLIFADDR, (caddr_t)&lifr) < 0)
                                return (ipadm_errno2status(errno));
                        if (is_persistent) {
                                status = i_ipadm_persist_if(iph,
                                    ifname, af, ipadm_flags);
                                if (status != IPADM_SUCCESS) {
                                        (void) i_ipadm_delete_if(iph, ifname,
                                            af, IPADM_OPT_ACTIVE);
                                }
                        }
                }
                return (status);
        }

        dlpi_flags = DLPI_NOATTACH;

        /*
         * If IPADM_OPT_IPMP is specified, then this is a request
         * to create an IPMP interface atop /dev/ipmpstub0.  (We can't simply
         * pass "ipmpstub0" as devname since an admin *could* have a normal
         * vanity-named link named "ipmpstub0" that they'd like to plumb.)
         */
        if (ipadm_flags & IPADM_OPT_IPMP) {
                dlpi_flags |= DLPI_DEVONLY;
                linkname = "ipmpstub0";
        } else {
                /*
                 * Verify that the user is not creating a persistent
                 * IP interface on a non-persistent data-link.
                 */
                if (!i_ipadm_is_vni(ifname) && dlstatus == DLADM_STATUS_OK &&
                    is_persistent && !(dlflags & DLADM_OPT_PERSIST)) {
                                return (IPADM_TEMPORARY_OBJ);
                }
                linkname = ifname;
        }

        /*
         * We use DLPI_NOATTACH because the ip module will do the attach
         * itself for DLPI style-2 devices.
         */
        if (dlpi_open(linkname, &dh_ip, dlpi_flags) != DLPI_SUCCESS)
                return (IPADM_DLPI_FAILURE);
        ip_fd = dlpi_fd(dh_ip);
        if (ioctl(ip_fd, I_PUSH, IP_MOD_NAME) == -1) {
                status = ipadm_errno2status(errno);
                goto done;
        }

        /*
         * Set IFF_IPV4/IFF_IPV6 flags. The kernel only allows modifications
         * to IFF_IPv4, IFF_IPV6, IFF_BROADCAST, IFF_XRESOLV, IFF_NOLINKLOCAL.
         */
        ifflags = 0;

        /* Set the name string and the IFF_IPV* flag */
        if (af == AF_INET) {
                ifflags = IFF_IPV4;
        } else {
                ifflags = IFF_IPV6;
                /*
                 * With the legacy method, the link-local address should be
                 * configured as part of the interface plumb, using the default
                 * token. If IPH_LEGACY is not specified, we want to set :: as
                 * the address and require the admin to explicitly call
                 * ipadm_create_addr() with the address object type set to
                 * IPADM_ADDR_IPV6_ADDRCONF to create the link-local address
                 * as well as the autoconfigured addresses.
                 */
                if (!legacy && !i_ipadm_is_6to4(iph, ifname))
                        ifflags |= IFF_NOLINKLOCAL;
        }
        (void) strlcpy(newif, ifname, sizeof (newif));
        status = i_ipadm_slifname(iph, ifname, newif, ifflags, ip_fd,
            ipadm_flags);
        if (status != IPADM_SUCCESS)
                goto done;

        /* Get the full set of existing flags for this stream */
        status = i_ipadm_get_flags(iph, newif, af, &ifflags);
        if (status != IPADM_SUCCESS)
                goto done;

        udp_dev_name = (af == AF_INET6 ? UDP6_DEV_NAME : UDP_DEV_NAME);
        status = ipadm_open_arp_on_udp(udp_dev_name, &mux_fd);
        if (status != IPADM_SUCCESS)
                goto done;

        /* Check if arp is not needed */
        if (ifflags & (IFF_NOARP|IFF_IPV6)) {
                /*
                 * PLINK the interface stream so that the application can exit
                 * without tearing down the stream.
                 */
                if ((ip_muxid = ioctl(mux_fd, I_PLINK, ip_fd)) == -1)
                        status = ipadm_errno2status(errno);
                goto done;
        }

        /*
         * This interface does use ARP, so set up a separate stream
         * from the interface to ARP.
         *
         * We use DLPI_NOATTACH because the arp module will do the attach
         * itself for DLPI style-2 devices.
         */
        if (dlpi_open(linkname, &dh_arp, dlpi_flags) != DLPI_SUCCESS) {
                status = IPADM_DLPI_FAILURE;
                goto done;
        }

        arp_fd = dlpi_fd(dh_arp);
        if (ioctl(arp_fd, I_PUSH, ARP_MOD_NAME) == -1) {
                status = ipadm_errno2status(errno);
                goto done;
        }

        status = i_ipadm_slifname_arp(newif, ifflags, arp_fd);
        if (status != IPADM_SUCCESS)
                goto done;
        /*
         * PLINK the IP and ARP streams so that ifconfig can exit
         * without tearing down the stream.
         */
        if ((ip_muxid = ioctl(mux_fd, I_PLINK, ip_fd)) == -1) {
                status = ipadm_errno2status(errno);
                goto done;
        }

        if (ioctl(mux_fd, I_PLINK, arp_fd) < 0) {
                status = ipadm_errno2status(errno);
                (void) ioctl(mux_fd, I_PUNLINK, ip_muxid);
        }

done:
        dlpi_close(dh_ip);
        if (dh_arp != NULL)
                dlpi_close(dh_arp);

        if (mux_fd != -1)
                (void) close(mux_fd);

        if (status == IPADM_SUCCESS) {
                /* copy back new ifname */
                (void) strlcpy(ifname, newif, LIFNAMSIZ);
                /*
                 * If it is a 6to4 tunnel, create a default
                 * addrobj name for the default address on the 0'th
                 * logical interface and set IFF_UP in the interface flags.
                 */
                if (i_ipadm_is_6to4(iph, ifname)) {
                        struct ipadm_addrobj_s addr;

                        i_ipadm_init_addr(&addr, ifname, "", IPADM_ADDR_STATIC);
                        addr.ipadm_af = af;
                        status = i_ipadm_lookupadd_addrobj(iph, &addr);
                        if (status != IPADM_SUCCESS)
                                return (status);
                        status = ipadm_add_aobjname(iph, ifname,
                            af, addr.ipadm_aobjname, IPADM_ADDR_STATIC, 0);
                        if (status != IPADM_SUCCESS)
                                return (status);
                        addr.ipadm_lifnum = 0;
                        i_ipadm_addrobj2lifname(&addr, lifname,
                            sizeof (lifname));
                        status = i_ipadm_set_flags(iph, lifname, af,
                            IFF_UP, 0);
                        if (status != IPADM_SUCCESS)
                                return (status);
                } else {
                        /*
                         * Prevent static IPv6 addresses from triggering
                         * autoconf. This does not have to be done for
                         * 6to4 tunnel interfaces, since in.ndpd will
                         * not autoconfigure those interfaces.
                         */
                        if (af == AF_INET6 && !legacy)
                                (void) i_ipadm_disable_autoconf(newif);
                }

                /*
                 * If IPADM_OPT_PERSIST was set in flags, store the
                 * interface in persistent DB.
                 */
                if (is_persistent) {
                        status = i_ipadm_persist_if(iph,
                            newif, af, ipadm_flags);
                        if (status != IPADM_SUCCESS) {
                                (void) i_ipadm_delete_if(iph, newif, af,
                                    IPADM_OPT_ACTIVE);
                        }
                }
        }
        if (status == IPADM_EXISTS)
                status = IPADM_IF_EXISTS;
        return (status);
}

/*
 * Unplumbs the interface in `ifname' of family `af'.
 */
ipadm_status_t
i_ipadm_unplumb_if(ipadm_handle_t iph, const char *ifname, sa_family_t af)
{
        int             ip_muxid, arp_muxid;
        int             mux_fd = -1;
        int             muxid_fd = -1;
        char            *udp_dev_name;
        uint64_t        flags;
        boolean_t       changed_arp_muxid = B_FALSE;
        int             save_errno;
        struct lifreq   lifr;
        ipadm_status_t  ret = IPADM_SUCCESS;
        int             sock;
        lifgroupinfo_t  lifgr;
        ifaddrlistx_t   *ifaddrs, *ifaddrp;
        boolean_t       v6 = (af == AF_INET6);

        /* Just do SIOCLIFREMOVEIF on loopback interfaces */
        bzero(&lifr, sizeof (lifr));
        if (i_ipadm_is_loopback(ifname) ||
            (i_ipadm_get_lnum(ifname) != 0 && (iph->iph_flags & IPH_LEGACY))) {
                (void) strlcpy(lifr.lifr_name, ifname, sizeof (lifr.lifr_name));
                if (ioctl((af == AF_INET) ? iph->iph_sock : iph->iph_sock6,
                    SIOCLIFREMOVEIF, (caddr_t)&lifr) < 0) {
                        return (ipadm_errno2status(errno));
                }
                return (IPADM_SUCCESS);
        }

        /*
         * We used /dev/udp or udp6 to set up the mux. So we have to use
         * the same now for PUNLINK also.
         */
        if (v6) {
                udp_dev_name = UDP6_DEV_NAME;
                sock = iph->iph_sock6;
        } else {
                udp_dev_name = UDP_DEV_NAME;
                sock = iph->iph_sock;
        }
        if ((muxid_fd = open(udp_dev_name, O_RDWR)) == -1) {
                ret = ipadm_errno2status(errno);
                goto done;
        }
        ret = ipadm_open_arp_on_udp(udp_dev_name, &mux_fd);
        if (ret != IPADM_SUCCESS)
                goto done;
        (void) strlcpy(lifr.lifr_name, ifname, sizeof (lifr.lifr_name));
        if (ioctl(muxid_fd, SIOCGLIFFLAGS, (caddr_t)&lifr) < 0) {
                ret = ipadm_errno2status(errno);
                goto done;
        }
        flags = lifr.lifr_flags;
again:
        if (flags & IFF_IPMP) {
                /*
                 * There are two reasons the I_PUNLINK can fail with EBUSY:
                 * (1) if IP interfaces are in the group, or (2) if IPMP data
                 * addresses are administratively up.  For case (1), we fail
                 * here with a specific error message.  For case (2), we bring
                 * down the addresses prior to doing the I_PUNLINK.  If the
                 * I_PUNLINK still fails with EBUSY then the configuration
                 * must have changed after our checks, in which case we branch
                 * back up to `again' and rerun this logic.  The net effect is
                 * that unplumbing an IPMP interface will only fail with EBUSY
                 * if IP interfaces are in the group.
                 */
                if (ioctl(sock, SIOCGLIFGROUPNAME, &lifr) == -1) {
                        ret = ipadm_errno2status(errno);
                        goto done;
                }
                (void) strlcpy(lifgr.gi_grname, lifr.lifr_groupname,
                    LIFGRNAMSIZ);
                if (ioctl(sock, SIOCGLIFGROUPINFO, &lifgr) == -1) {
                        ret = ipadm_errno2status(errno);
                        goto done;
                }
                if ((v6 && lifgr.gi_nv6 != 0) || (!v6 && lifgr.gi_nv4 != 0)) {
                        ret = IPADM_GRP_NOTEMPTY;
                        goto done;
                }

                /*
                 * The kernel will fail the I_PUNLINK if the IPMP interface
                 * has administratively up addresses; bring them down.
                 */
                if (ifaddrlistx(ifname, IFF_UP|IFF_DUPLICATE,
                    0, &ifaddrs) == -1) {
                        ret = ipadm_errno2status(errno);
                        goto done;
                }
                ifaddrp = ifaddrs;
                for (; ifaddrp != NULL; ifaddrp = ifaddrp->ia_next) {
                        int sock = (ifaddrp->ia_flags & IFF_IPV4) ?
                            iph->iph_sock : iph->iph_sock6;
                        struct lifreq lifrl;

                        if (((ifaddrp->ia_flags & IFF_IPV6) && !v6) ||
                            (!(ifaddrp->ia_flags & IFF_IPV6) && v6))
                                continue;

                        bzero(&lifrl, sizeof (lifrl));
                        (void) strlcpy(lifrl.lifr_name, ifaddrp->ia_name,
                            sizeof (lifrl.lifr_name));
                        if (ioctl(sock, SIOCGLIFFLAGS, &lifrl) < 0) {
                                ret = ipadm_errno2status(errno);
                                ifaddrlistx_free(ifaddrs);
                                goto done;
                        }
                        if (lifrl.lifr_flags & IFF_UP) {
                                ret = i_ipadm_set_flags(iph, lifrl.lifr_name,
                                    ((lifrl.lifr_flags & IFF_IPV4) ? AF_INET :
                                    AF_INET6), 0, IFF_UP);
                                if (ret != IPADM_SUCCESS) {
                                        ifaddrlistx_free(ifaddrs);
                                        goto done;
                                }
                        } else if (lifrl.lifr_flags & IFF_DUPLICATE) {
                                if (ioctl(sock, SIOCGLIFADDR, &lifrl) < 0 ||
                                    ioctl(sock, SIOCSLIFADDR, &lifrl) < 0) {
                                        ret = ipadm_errno2status(errno);
                                        ifaddrlistx_free(ifaddrs);
                                        goto done;
                                }
                        }
                }
                ifaddrlistx_free(ifaddrs);
        }

        if (ioctl(muxid_fd, SIOCGLIFMUXID, (caddr_t)&lifr) < 0) {
                ret = ipadm_errno2status(errno);
                goto done;
        }
        arp_muxid = lifr.lifr_arp_muxid;
        ip_muxid = lifr.lifr_ip_muxid;

        /*
         * We don't have a good way of knowing whether the arp stream is
         * plumbed. We can't rely on IFF_NOARP because someone could
         * have turned it off later using "ifconfig xxx -arp".
         */
        if (arp_muxid != 0) {
                if (ioctl(mux_fd, I_PUNLINK, arp_muxid) < 0) {
                        /*
                         * See the comment before the SIOCGLIFGROUPNAME call.
                         */
                        if (errno == EBUSY && (flags & IFF_IPMP))
                                goto again;

                        if ((errno == EINVAL) &&
                            (flags & (IFF_NOARP | IFF_IPV6))) {
                                /*
                                 * Some plumbing utilities set the muxid to
                                 * -1 or some invalid value to signify that
                                 * there is no arp stream. Set the muxid to 0
                                 * before trying to unplumb the IP stream.
                                 * IP does not allow the IP stream to be
                                 * unplumbed if it sees a non-null arp muxid,
                                 * for consistency of IP-ARP streams.
                                 */
                                lifr.lifr_arp_muxid = 0;
                                (void) ioctl(muxid_fd, SIOCSLIFMUXID,
                                    (caddr_t)&lifr);
                                changed_arp_muxid = B_TRUE;
                        }
                        /*
                         * In case of any other error, we continue with
                         * the unplumb.
                         */
                }
        }

        if (ioctl(mux_fd, I_PUNLINK, ip_muxid) < 0) {
                if (changed_arp_muxid) {
                        /*
                         * Some error occurred, and we need to restore
                         * everything back to what it was.
                         */
                        save_errno = errno;
                        lifr.lifr_arp_muxid = arp_muxid;
                        lifr.lifr_ip_muxid = ip_muxid;
                        (void) ioctl(muxid_fd, SIOCSLIFMUXID, (caddr_t)&lifr);
                        errno = save_errno;
                }
                /*
                 * See the comment before the SIOCGLIFGROUPNAME call.
                 */
                if (errno == EBUSY && (flags & IFF_IPMP))
                        goto again;

                ret = ipadm_errno2status(errno);
        }
done:
        if (muxid_fd != -1)
                (void) close(muxid_fd);
        if (mux_fd != -1)
                (void) close(mux_fd);

        if (af == AF_INET6 && ret == IPADM_SUCCESS) {
                /*
                 * in.ndpd maintains the phyints in its memory even after
                 * the interface is plumbed, so that it can be reused when
                 * the interface gets plumbed again. The default behavior
                 * of in.ndpd is to start autoconfiguration for an interface
                 * that gets plumbed. We need to send the
                 * message IPADM_ENABLE_AUTOCONF to in.ndpd to restore this
                 * default behavior on replumb.
                 */
                (void) i_ipadm_enable_autoconf(ifname);
        }
        return (ret);
}

/*
 * Saves the given interface name `ifname' with address family `af' in
 * persistent DB.
 */
static ipadm_status_t
i_ipadm_persist_if(ipadm_handle_t iph, const char *ifname, sa_family_t af,
    uint32_t ipadm_flags)
{
        ipmgmt_if_arg_t         ifarg;
        int                     err;

        (void) strlcpy(ifarg.ia_ifname, ifname, sizeof (ifarg.ia_ifname));
        ifarg.ia_family = af;
        if (ipadm_flags & IPADM_OPT_IPMP)
                ifarg.ia_ifclass = IPADM_IF_CLASS_IPMP;
        else
                ifarg.ia_ifclass = IPADM_IF_CLASS_REGULAR;

        ifarg.ia_cmd = IPMGMT_CMD_SETIF;
        ifarg.ia_flags = IPMGMT_PERSIST;
        err = ipadm_door_call(iph, &ifarg, sizeof (ifarg), NULL, 0, B_FALSE);
        return (ipadm_errno2status(err));
}

/*
 * Remove the IP interface from active configuration. If IPADM_OPT_PERSIST
 * is set in `ipadm_flags', it is also removed from persistent configuration.
 */
ipadm_status_t
i_ipadm_delete_if(ipadm_handle_t iph, const char *ifname, sa_family_t af,
    uint32_t ipadm_flags)
{
        ipadm_status_t          ret = IPADM_SUCCESS;
        ipadm_status_t          db_status;
        char                    tmp_ifname[LIFNAMSIZ];
        char                    *cp;
        struct ipadm_addrobj_s  ipaddr;
        boolean_t               is_persistent =
            (ipadm_flags & IPADM_OPT_PERSIST);

        ret = i_ipadm_unplumb_if(iph, ifname, af);
        if (ret != IPADM_SUCCESS)
                goto done;

        cp = strrchr(ifname, IPADM_LOGICAL_SEP);
        if (cp != NULL) {
                assert(iph->iph_flags & IPH_LEGACY);
                /*
                 * This is a non-zero logical interface.
                 * Find the addrobj and remove it from the daemon's memory.
                 */
                (void) strlcpy(tmp_ifname, ifname, sizeof (tmp_ifname));
                tmp_ifname[cp - ifname] = '\0';
                *cp++ = '\0';
                ipaddr.ipadm_lifnum = atoi(cp);
                (void) strlcpy(ipaddr.ipadm_ifname, tmp_ifname,
                    sizeof (ipaddr.ipadm_ifname));
                ipaddr.ipadm_af = af;
                ret = i_ipadm_get_lif2addrobj(iph, &ipaddr);
                if (ret == IPADM_SUCCESS) {
                        ret = i_ipadm_delete_addrobj(iph, &ipaddr,
                            IPADM_OPT_ACTIVE);
                } else if (ret == IPADM_NOTFOUND) {
                        ret = IPADM_SUCCESS;
                }
                return (ret);
        }
done:
        /*
         * Even if interface does not exist, remove all its addresses and
         * properties from the persistent store. If interface does not
         * exist both in kernel and the persistent store, return IPADM_ENXIO.
         */
        if ((ret == IPADM_ENXIO && is_persistent) || ret == IPADM_SUCCESS) {
                db_status = i_ipadm_delete_ifobj(iph, ifname, af,
                    is_persistent);
                if (db_status == IPADM_SUCCESS)
                        ret = IPADM_SUCCESS;
        }

        return (ret);
}

/*
 * Resets all addresses on interface `ifname' with address family `af'
 * from ipmgmtd daemon. If is_persistent = B_TRUE, all interface properties
 * and address objects of `ifname' for `af' are also removed from the
 * persistent DB.
 */
ipadm_status_t
i_ipadm_delete_ifobj(ipadm_handle_t iph, const char *ifname, sa_family_t af,
    boolean_t is_persistent)
{
        ipmgmt_if_arg_t         ifarg;
        int                     err;

        ifarg.ia_cmd = IPMGMT_CMD_RESETIF;
        ifarg.ia_flags = IPMGMT_ACTIVE;
        if (is_persistent)
                ifarg.ia_flags |= IPMGMT_PERSIST;
        ifarg.ia_family = af;
        (void) strlcpy(ifarg.ia_ifname, ifname, LIFNAMSIZ);

        err = ipadm_door_call(iph, &ifarg, sizeof (ifarg), NULL, 0, B_FALSE);
        return (ipadm_errno2status(err));
}

/*
 * Create the interface by plumbing it for IP.
 * This function will check if there is saved configuration information
 * for `ifname' and return IPADM_OP_DISABLE_OBJ if the name-space
 * for `ifname' is taken.
 */
ipadm_status_t
i_ipadm_create_if(ipadm_handle_t iph, char *ifname, sa_family_t af,
    uint32_t ipadm_flags)
{
        ipadm_status_t  status;
        boolean_t       p_exists;
        sa_family_t     other_af;

        /*
         * Return error, if the interface already exists in either the active
         * or the persistent configuration.
         */
        if (ipadm_if_enabled(iph, ifname, af))
                return (IPADM_IF_EXISTS);

        if (!(iph->iph_flags & IPH_LEGACY)) {
                status = i_ipadm_if_pexists(iph, ifname, af, &p_exists);
                if (status != IPADM_SUCCESS)
                        return (status);
                other_af = (af == AF_INET ? AF_INET6 : AF_INET);
                if (p_exists) {
                        if (!ipadm_if_enabled(iph, ifname, other_af))
                                return (IPADM_OP_DISABLE_OBJ);
                        else
                                ipadm_flags &= ~IPADM_OPT_PERSIST;
                }
        }

        return (i_ipadm_plumb_if(iph, ifname, af, ipadm_flags));
}

/*
 * Plumbs an interface. Creates both IPv4 and IPv6 interfaces by
 * default, unless a value in `af' is specified. The interface may be plumbed
 * only if there is no previously saved persistent configuration information
 * for the interface (in which case the ipadm_enable_if() function must
 * be used to enable the interface).
 *
 * Returns: IPADM_SUCCESS, IPADM_FAILURE, IPADM_IF_EXISTS,
 * IPADM_IF_PERSIST_EXISTS, IPADM_DLPI_FAILURE,
 * or appropriate ipadm_status_t corresponding to the errno.
 *
 * `ifname' must point to memory that can hold upto LIFNAMSIZ chars. It may
 * be over-written with the actual interface name when a PPA has to be
 * internally generated by the library.
 */
ipadm_status_t
ipadm_create_if(ipadm_handle_t iph, char *ifname, sa_family_t af,
    uint32_t flags)
{
        ipadm_status_t  status;
        boolean_t       created_v4 = B_FALSE;
        char            newifname[LIFNAMSIZ];

        /* Check for the required authorization */
        if (!ipadm_check_auth())
                return (IPADM_EAUTH);

        if (flags == 0 || ((flags & IPADM_OPT_PERSIST) &&
            !(flags & IPADM_OPT_ACTIVE)) ||
            (flags & ~(IPADM_COMMON_OPT_MASK | IPADM_OPT_IPMP |
            IPADM_OPT_GENPPA))) {
                return (IPADM_INVALID_ARG);
        }
        if (flags & IPADM_OPT_GENPPA) {
                if (snprintf(newifname, LIFNAMSIZ, "%s0", ifname) >=
                    LIFNAMSIZ)
                        return (IPADM_INVALID_ARG);
        } else {
                if (strlcpy(newifname, ifname, LIFNAMSIZ) >= LIFNAMSIZ)
                        return (IPADM_INVALID_ARG);
        }

        if (!i_ipadm_validate_ifname(iph, newifname))
                return (IPADM_INVALID_ARG);

        if ((af == AF_INET || af == AF_UNSPEC) &&
            !i_ipadm_is_6to4(iph, ifname)) {
                status = i_ipadm_create_if(iph, ifname, AF_INET, flags);
                if (status != IPADM_SUCCESS)
                        return (status);
                created_v4 = B_TRUE;
        }
        if (af == AF_INET6 || af == AF_UNSPEC) {
                status = i_ipadm_create_if(iph, ifname, AF_INET6, flags);
                if (status != IPADM_SUCCESS) {
                        if (created_v4) {
                                (void) i_ipadm_delete_if(iph, ifname, AF_INET,
                                    IPADM_OPT_ACTIVE);
                        }
                        return (status);
                }
        }

        return (IPADM_SUCCESS);
}

ipadm_status_t
ipadm_add_ipmp_member(ipadm_handle_t iph, const char *gifname,
    const char *mifname, uint32_t ipadm_flags)
{
        return (i_ipadm_update_ipmp(iph, gifname, mifname,
            ipadm_flags, IPADM_ADD_IPMP));
}

ipadm_status_t
ipadm_remove_ipmp_member(ipadm_handle_t iph, const char *gifname,
    const char *mifname, uint32_t ipadm_flags)
{
        return (i_ipadm_update_ipmp(iph, gifname, mifname,
            ipadm_flags, IPADM_REMOVE_IPMP));
}

/*
 * Updates active IPMP configuration according to the specified
 * command. It also persists the configuration if IPADM_OPT_PERSIST
 * is set in `ipadm_flags'.
 */
static ipadm_status_t
i_ipadm_update_ipmp(ipadm_handle_t iph, const char *gifname,
    const char *mifname, uint32_t ipadm_flags, ipadm_ipmp_op_t op)
{
        ipadm_status_t status;
        char    groupname1[LIFGRNAMSIZ];
        char    groupname2[LIFGRNAMSIZ];

        /* Check for the required authorization */
        if (!ipadm_check_auth())
                return (IPADM_EAUTH);

        if (!(ipadm_flags & IPADM_OPT_ACTIVE) ||
            gifname == NULL || mifname == NULL)
                return (IPADM_INVALID_ARG);

        if (!ipadm_if_enabled(iph, gifname, AF_UNSPEC) ||
            !ipadm_if_enabled(iph, mifname, AF_UNSPEC))
                return (IPADM_OP_DISABLE_OBJ);

        if (!i_ipadm_is_ipmp(iph, gifname))
                return (IPADM_INVALID_ARG);

        if (op == IPADM_ADD_IPMP && i_ipadm_is_under_ipmp(iph, mifname))
                return (IPADM_IF_INUSE);

        if ((status = i_ipadm_get_groupname_active(iph, gifname,
            groupname2, sizeof (groupname2))) != IPADM_SUCCESS)
                return (status);

        if (op == IPADM_REMOVE_IPMP) {
                if ((status = i_ipadm_get_groupname_active(iph, mifname,
                    groupname1, sizeof (groupname1))) != IPADM_SUCCESS)
                        return (status);

                if (groupname1[0] == '\0' ||
                    strcmp(groupname1, groupname2) != 0)
                        return (IPADM_INVALID_ARG);

                groupname2[0] = '\0';
        }

        if ((ipadm_flags & IPADM_OPT_PERSIST) &&
            (status = i_ipadm_persist_update_ipmp(iph, gifname,
            mifname, op)) != IPADM_SUCCESS)
                return (status);

        return (i_ipadm_set_groupname_active(iph, mifname, groupname2));
}

/*
 * Call the ipmgmtd to update the IPMP configuration in ipadm DB.
 * After this call the DB will know that mifname is under gifname and
 * gifname has a member, which name is mifname.
 */
static ipadm_status_t
i_ipadm_persist_update_ipmp(ipadm_handle_t iph, const char *gifname,
    const char *mifname, ipadm_ipmp_op_t op)
{
        ipmgmt_ipmp_update_arg_t args;
        int err;

        assert(op == IPADM_ADD_IPMP || op == IPADM_REMOVE_IPMP);

        bzero(&args, sizeof (ipmgmt_ipmp_update_arg_t));

        args.ia_cmd = IPMGMT_CMD_IPMP_UPDATE;

        (void) strlcpy(args.ia_gifname, gifname, sizeof (args.ia_gifname));
        (void) strlcpy(args.ia_mifname, mifname, sizeof (args.ia_mifname));

        if (op == IPADM_ADD_IPMP)
                args.ia_flags = IPMGMT_APPEND;
        else
                args.ia_flags = IPMGMT_REMOVE;

        args.ia_flags |= IPMGMT_PERSIST;

        err = ipadm_door_call(iph, &args, sizeof (args), NULL, 0, B_FALSE);
        return (ipadm_errno2status(err));
}

/*
 * Deletes the interface in `ifname'. Removes both IPv4 and IPv6 interfaces
 * when `af' = AF_UNSPEC.
 */
ipadm_status_t
ipadm_delete_if(ipadm_handle_t iph, const char *ifname, sa_family_t af,
    uint32_t flags)
{
        ipadm_status_t status1 = IPADM_SUCCESS;
        ipadm_status_t status2 = IPADM_SUCCESS;
        ipadm_status_t other;

        /* Check for the required authorization */
        if (!ipadm_check_auth())
                return (IPADM_EAUTH);

        /* Validate the `ifname' for any logical interface. */
        if (flags == 0 || (flags & ~(IPADM_COMMON_OPT_MASK)) ||
            !i_ipadm_validate_ifname(iph, ifname))
                return (IPADM_INVALID_ARG);

        if (af == AF_INET || af == AF_UNSPEC)
                status1 = i_ipadm_delete_if(iph, ifname, AF_INET, flags);
        if (af == AF_INET6 || af == AF_UNSPEC)
                status2 = i_ipadm_delete_if(iph, ifname, AF_INET6, flags);
        /*
         * If the family has been uniquely identified, we return the
         * associated status, even if that is ENXIO. Calls from ifconfig
         * which can only unplumb one of IPv4/IPv6 at any time fall under
         * this category.
         */
        if (af == AF_INET)
                return (status1);
        else if (af == AF_INET6)
                return (status2);
        else if (af != AF_UNSPEC)
                return (IPADM_INVALID_ARG);

        /*
         * If af is AF_UNSPEC, then we return the following:
         * status1,             if status1 == status2
         * IPADM_SUCCESS,       if either of status1 or status2 is SUCCESS
         *                      and the other status is ENXIO
         * IPADM_ENXIO,         if both status1 and status2 are ENXIO
         * IPADM_FAILURE        otherwise.
         */
        if (status1 == status2) {
                /* covers the case when both status1 and status2 are ENXIO */
                return (status1);
        } else if (status1 == IPADM_SUCCESS || status2 == IPADM_SUCCESS) {
                if (status1 == IPADM_SUCCESS)
                        other = status2;
                else
                        other = status1;
                return (other == IPADM_ENXIO ? IPADM_SUCCESS : IPADM_FAILURE);
        } else {
                return (IPADM_FAILURE);
        }
}

/*
 * Returns information about all interfaces in both active and persistent
 * configuration. If `ifname' is not NULL, it returns only the interface
 * identified by `ifname'.
 *
 * Return values:
 *      On success: IPADM_SUCCESS.
 *      On error  : IPADM_INVALID_ARG, IPADM_ENXIO or IPADM_FAILURE.
 */
ipadm_status_t
ipadm_if_info(ipadm_handle_t iph, const char *ifname,
    ipadm_if_info_t **if_info, uint32_t flags, int64_t lifc_flags)
{
        ipadm_status_t  status;
        ifspec_t        ifsp;

        if (if_info == NULL || iph == NULL || flags != 0)
                return (IPADM_INVALID_ARG);

        if (ifname != NULL &&
            (!ifparse_ifspec(ifname, &ifsp) || ifsp.ifsp_lunvalid)) {
                return (IPADM_INVALID_ARG);
        }

        status = i_ipadm_get_all_if_info(iph, ifname, if_info, lifc_flags);
        if (status != IPADM_SUCCESS)
                return (status);
        if (ifname != NULL && *if_info == NULL)
                return (IPADM_ENXIO);

        return (IPADM_SUCCESS);
}

/*
 * Frees the linked list allocated by ipadm_if_info().
 */
void
ipadm_free_if_info(ipadm_if_info_t *ifinfo)
{
        ipadm_if_info_t *ifinfo_next;

        for (; ifinfo != NULL; ifinfo = ifinfo_next) {
                ifinfo_next = ifinfo->ifi_next;
                i_ipadm_free_ipmp_members(&ifinfo->ifi_ipmp_cmembers);
                i_ipadm_free_ipmp_members(&ifinfo->ifi_ipmp_pmembers);
                free(ifinfo);
        }
}

static void
i_ipadm_free_ipmp_members(ipadm_ipmp_members_t *ipmp_members)
{
        ipadm_ipmp_member_t *ipmp_member;

        while ((ipmp_member = list_remove_head(ipmp_members)) != NULL)
                free(ipmp_member);

        list_destroy(ipmp_members);
}

/*
 * Re-enable the interface `ifname' based on the saved configuration
 * for `ifname'.
 */
ipadm_status_t
ipadm_enable_if(ipadm_handle_t iph, const char *ifname, uint32_t flags)
{
        boolean_t       set_init = B_FALSE;
        nvlist_t        *ifnvl;
        ipadm_status_t  status;
        ifspec_t        ifsp;

        /* Check for the required authorization */
        if (!ipadm_check_auth())
                return (IPADM_EAUTH);

        /* Check for logical interfaces. */
        if (!ifparse_ifspec(ifname, &ifsp) || ifsp.ifsp_lunvalid)
                return (IPADM_INVALID_ARG);

        /* Enabling an interface persistently is not supported. */
        if (flags & IPADM_OPT_PERSIST)
                return (IPADM_NOTSUP);

        /*
         * Return early by checking if the interface is already enabled.
         */
        if (ipadm_if_enabled(iph, ifname, AF_INET) &&
            ipadm_if_enabled(iph, ifname, AF_INET6))
                return (IPADM_IF_EXISTS);

        /*
         * Enable the interface and restore all its interface properties
         * and address objects.
         */
        status = i_ipadm_init_ifs(iph, ifname, &ifnvl);
        if (status != IPADM_SUCCESS)
                return (status);

        assert(ifnvl != NULL);
        /*
         * ipadm_enable_if() does exactly what ipadm_init_ifs() does,
         * but only for one interface. We need to set IPH_INIT because
         * ipmgmtd daemon does not have to write the interface to the
         * persistent db. The interface is already available in the
         * persistent db and we are here to re-enable the persistent
         * configuration.
         *
         * But we need to make sure we're not accidentally clearing an
         * IPH_INIT flag that was already set when we were called.
         */
        if ((iph->iph_flags & IPH_INIT) == 0) {
                iph->iph_flags |= IPH_INIT;
                set_init = B_TRUE;
        }

        status = i_ipadm_init_ifobj(iph, ifname, ifnvl);

        if (set_init)
                iph->iph_flags &= ~IPH_INIT;

        nvlist_free(ifnvl);
        return (status);
}

/*
 * Disable the interface `ifname' by removing it from the active configuration.
 * Error code return values follow the model in ipadm_delete_if()
 */
ipadm_status_t
ipadm_disable_if(ipadm_handle_t iph, const char *ifname, uint32_t flags)
{
        ipadm_status_t  status1, status2, other;
        ifspec_t        ifsp;

        /* Check for the required authorization */
        if (!ipadm_check_auth())
                return (IPADM_EAUTH);

        /* Check for logical interfaces. */
        if (!ifparse_ifspec(ifname, &ifsp) || ifsp.ifsp_lunvalid)
                return (IPADM_INVALID_ARG);

        /* Disabling an interface persistently is not supported. */
        if (flags & IPADM_OPT_PERSIST)
                return (IPADM_NOTSUP);

        status1 = i_ipadm_unplumb_if(iph, ifname, AF_INET6);
        if (status1 == IPADM_SUCCESS)
                status1 = i_ipadm_delete_ifobj(iph, ifname, AF_INET6, B_FALSE);
        status2 = i_ipadm_unplumb_if(iph, ifname, AF_INET);
        if (status2 == IPADM_SUCCESS)
                status2 = i_ipadm_delete_ifobj(iph, ifname, AF_INET, B_FALSE);
        if (status1 == status2) {
                return (status2);
        } else if (status1 == IPADM_SUCCESS || status2 == IPADM_SUCCESS) {
                if (status1 == IPADM_SUCCESS)
                        other = status2;
                else
                        other = status1;
                return (other == IPADM_ENXIO ? IPADM_SUCCESS : IPADM_FAILURE);
        } else {
                return (IPADM_FAILURE);
        }
}

/*
 * FIXME Remove this when ifconfig(8) is updated to use IPMP support
 * in libipadm.
 */
/*
 * This workaround is required by ifconfig(8) whenever an
 * interface is moved into an IPMP group to update the daemon's
 * in-memory mapping of `aobjname' to 'lifnum'.
 *
 * For `IPMGMT_ACTIVE' case, i_ipadm_delete_ifobj() would only fail if
 * door_call(3C) fails. Also, there is no use in returning error because
 * `ifname' would have been successfuly moved into IPMP group, by this time.
 */
void
ipadm_if_move(ipadm_handle_t iph, const char *ifname)
{
        (void) i_ipadm_delete_ifobj(iph, ifname, AF_INET, B_FALSE);
        (void) i_ipadm_delete_ifobj(iph, ifname, AF_INET6, B_FALSE);
}

ipadm_status_t
i_ipadm_set_groupname_active(ipadm_handle_t iph, const char *ifname,
    const char *groupname)
{
        struct lifreq   lifr;
        ipadm_addr_info_t *addrinfo, *ia;
        ipadm_status_t  status = IPADM_SUCCESS;

        (void) memset(&lifr, 0, sizeof (lifr));

        (void) strlcpy(lifr.lifr_name, ifname, sizeof (lifr.lifr_name));
        (void) strlcpy(lifr.lifr_groupname, groupname,
            sizeof (lifr.lifr_groupname));

        /* Disable all addresses on the interface */
        (void) i_ipadm_active_addr_info(iph, ifname, &addrinfo,
            IPADM_OPT_ACTIVE | IPADM_OPT_ZEROADDR, IFF_UP | IFF_DUPLICATE);

        for (ia = addrinfo; ia != NULL; ia = IA_NEXT(ia)) {
                if (strlen(ia->ia_aobjname) > 0) {
                        (void) ipadm_disable_addr(iph, ia->ia_aobjname, 0);
                } else {
                        /*
                         * There's an address on this interfaces with no
                         * corresponding addrobj. Just clear IFF_UP.
                         */
                        (void) i_ipadm_set_flags(iph, ifname,
                            addrinfo->ia_ifa.ifa_addr->sa_family, 0, IFF_UP);
                }
        }

        if (ioctl(iph->iph_sock, SIOCSLIFGROUPNAME, (caddr_t)&lifr) == -1 &&
            ioctl(iph->iph_sock6, SIOCSLIFGROUPNAME, (caddr_t)&lifr) == -1)
                status = ipadm_errno2status(errno);

        /* Enable all addresses on the interface */
        for (ia = addrinfo; ia != NULL; ia = IA_NEXT(ia)) {
                if (strlen(ia->ia_aobjname) > 0) {
                        (void) ipadm_enable_addr(iph, ia->ia_aobjname, 0);
                } else {
                        /*
                         * There's an address on this interfaces with no
                         * corresponding addrobj. Just set IFF_UP.
                         */
                        (void) i_ipadm_set_flags(iph, ifname,
                            addrinfo->ia_ifa.ifa_addr->sa_family, IFF_UP, 0);
                }
        }

        if (status == IPADM_SUCCESS) {
                if (groupname[0] == '\0') {
                        /*
                         * If interface was removed from IPMP group, unset the
                         * DEPRECATED and NOFAILOVER flags.
                         */
                        (void) i_ipadm_set_flags(iph, ifname, AF_INET, 0,
                            IFF_DEPRECATED | IFF_NOFAILOVER);
                        (void) i_ipadm_set_flags(iph, ifname, AF_INET6, 0,
                            IFF_DEPRECATED | IFF_NOFAILOVER);
                } else if (addrinfo == NULL) {
                        /*
                         * If interface was added to IPMP group and there are no
                         * active addresses, explicitly bring it up to be used
                         * for link-based IPMP configuration.
                         */
                        (void) i_ipadm_set_flags(iph, ifname, AF_INET,
                            IFF_UP, 0);
                        (void) i_ipadm_set_flags(iph, ifname, AF_INET6,
                            IFF_UP, 0);
                }
        }

        ipadm_free_addr_info(addrinfo);

        return (status);
}

ipadm_status_t
i_ipadm_get_groupname_active(ipadm_handle_t iph, const char *ifname,
    char *groupname, size_t size)
{
        struct lifreq   lifr;

        (void) memset(&lifr, 0, sizeof (lifr));

        (void) strlcpy(lifr.lifr_name, ifname, sizeof (lifr.lifr_name));

        if (ioctl(iph->iph_sock, SIOCGLIFGROUPNAME, (caddr_t)&lifr) == -1 &&
            ioctl(iph->iph_sock6, SIOCGLIFGROUPNAME, (caddr_t)&lifr) == -1)
                return (ipadm_errno2status(errno));

        (void) strlcpy(groupname, lifr.lifr_groupname, size);

        return (IPADM_SUCCESS);
}

/*
 * Returns B_TRUE if `ifname' represents an IPMP underlying interface.
 */
boolean_t
i_ipadm_is_under_ipmp(ipadm_handle_t iph, const char *ifname)
{

        char    groupname[LIFGRNAMSIZ];

        if (i_ipadm_get_groupname_active(iph, ifname, groupname,
            sizeof (groupname)) != IPADM_SUCCESS ||
            groupname[0] == '\0' ||
            strcmp(ifname, groupname) == 0)
                return (B_FALSE);

        return (B_TRUE);
}

/*
 * Returns B_TRUE if `ifname' represents an IPMP group interface.
 */
boolean_t
i_ipadm_is_ipmp(ipadm_handle_t iph, const char *ifname)
{
        uint64_t flags;

        if (i_ipadm_get_flags(iph, ifname, AF_INET, &flags) != IPADM_SUCCESS &&
            i_ipadm_get_flags(iph, ifname, AF_INET6, &flags) != IPADM_SUCCESS)
                return (B_FALSE);

        return ((flags & IFF_IPMP) != 0);
}