/*
 * 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 2009 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 *
 * Copyright 2021 Tintri by DDN, Inc. All rights reserved.
 */

/*
 * IPMP query interfaces (see PSARC/2002/615 and PSARC/2007/272).
 */

#include <assert.h>
#include <errno.h>
#include <libinetutil.h>
#include <string.h>
#include <stdlib.h>
#include <unistd.h>
#include <sys/types.h>

#include "ipmp_impl.h"
#include "ipmp_mpathd.h"
#include "ipmp_query_impl.h"

static ipmp_ifinfo_t    *ipmp_ifinfo_clone(ipmp_ifinfo_t *);
static ipmp_addrinfo_t  *ipmp_addrinfo_clone(ipmp_addrinfo_t *);
static ipmp_addrlist_t  *ipmp_addrlist_clone(ipmp_addrlist_t *);
static ipmp_grouplist_t *ipmp_grouplist_clone(ipmp_grouplist_t *);
static ipmp_groupinfo_t *ipmp_groupinfo_clone(ipmp_groupinfo_t *);
static ipmp_iflist_t    *ipmp_iflist_create(uint_t, char (*)[LIFNAMSIZ]);
static void             ipmp_freeiflist(ipmp_iflist_t *);
static ipmp_addrlist_t *ipmp_addrlist_create(uint_t, struct sockaddr_storage *);
static void             ipmp_freeaddrlist(ipmp_addrlist_t *);
static ipmp_groupinfo_t *ipmp_snap_getgroupinfo(ipmp_snap_t *, const char *);
static ipmp_ifinfo_t    *ipmp_snap_getifinfo(ipmp_snap_t *, const char *);
static ipmp_addrinfo_t  *ipmp_snap_getaddrinfo(ipmp_snap_t *, const char *,
                            struct sockaddr_storage *);
static int              ipmp_snap_take(ipmp_state_t *, ipmp_snap_t **);
static boolean_t        ipmp_checktlv(ipmp_infotype_t, size_t, void *);
static int              ipmp_querydone(ipmp_state_t *, int);

/*
 * Using `statep', send a query request for `type' to in.mpathd, and if
 * necessary wait until at least `endtp' for a response.  Returns an IPMP
 * error code.  If successful, the caller may then read additional query
 * information through ipmp_readinfo(), and must eventually call
 * ipmp_querydone() to complete the query operation.  Only one query may be
 * outstanding on a given `statep' at a time.
 */
static int
ipmp_sendquery(ipmp_state_t *statep, ipmp_infotype_t type, const char *name,
    const void *addr, struct timeval *endtp)
{
        mi_query_t      query;
        mi_result_t     result;
        int             retval;

        query.miq_command = MI_QUERY;
        query.miq_inforeq = type;

        switch (type) {
        case IPMP_ADDRINFO:
                (void) strlcpy(query.miq_grname, name, LIFGRNAMSIZ);
                query.miq_addr = *(struct sockaddr_storage *)addr;
                break;

        case IPMP_GROUPINFO:
                (void) strlcpy(query.miq_grname, name, LIFGRNAMSIZ);
                break;

        case IPMP_IFINFO:
                (void) strlcpy(query.miq_ifname, name, LIFNAMSIZ);
                break;

        case IPMP_GROUPLIST:
        case IPMP_SNAP:
                break;

        default:
                assert(0);
        }

        if (gettimeofday(endtp, NULL) == -1)
                return (IPMP_FAILURE);

        endtp->tv_sec += IPMP_REQTIMEOUT;

        assert(statep->st_fd == -1);
        retval = ipmp_connect(&statep->st_fd);
        if (retval != IPMP_SUCCESS)
                return (retval);

        retval = ipmp_write(statep->st_fd, &query, sizeof (query));
        if (retval != IPMP_SUCCESS)
                return (ipmp_querydone(statep, retval));

        retval = ipmp_read(statep->st_fd, &result, sizeof (result), endtp);
        if (retval != IPMP_SUCCESS)
                return (ipmp_querydone(statep, retval));

        if (result.me_mpathd_error != IPMP_SUCCESS)
                return (ipmp_querydone(statep, result.me_mpathd_error));

        return (IPMP_SUCCESS);
}

/*
 * Using `statep', read a query response of type `infotype' into a dynamically
 * allocated buffer pointed to by `*infop', before the current time becomes
 * `endtp'.  Returns an IPMP error code.
 */
static int
ipmp_readinfo(ipmp_state_t *statep, ipmp_infotype_t infotype, void **infop,
    const struct timeval *endtp)
{
        int             retval;
        size_t          len;
        ipmp_infotype_t type;

        retval = ipmp_readtlv(statep->st_fd, &type, &len, infop, endtp);
        if (retval != IPMP_SUCCESS)
                return (retval);

        if (type != infotype || !ipmp_checktlv(type, len, *infop)) {
                free(*infop);
                return (IPMP_EPROTO);
        }

        return (IPMP_SUCCESS);
}

/*
 * Using `statep', read in the remaining IPMP group information TLVs from
 * in.mpathd into `grinfop' before the current time becomes `endtp'.  Returns
 * an IPMP error code.  On failure, `grinfop' will have its original contents.
 */
static int
ipmp_readgroupinfo_lists(ipmp_state_t *statep, ipmp_groupinfo_t *grinfop,
    const struct timeval *endtp)
{
        int retval;
        ipmp_iflist_t *iflistp;
        ipmp_addrlist_t *adlistp;

        retval = ipmp_readinfo(statep, IPMP_IFLIST, (void **)&iflistp, endtp);
        if (retval != IPMP_SUCCESS)
                return (retval);

        retval = ipmp_readinfo(statep, IPMP_ADDRLIST, (void **)&adlistp, endtp);
        if (retval != IPMP_SUCCESS) {
                ipmp_freeiflist(iflistp);
                return (retval);
        }

        grinfop->gr_iflistp = iflistp;
        grinfop->gr_adlistp = adlistp;
        return (IPMP_SUCCESS);
}

/*
 * Using `statep', read in the remaining IPMP interface information TLVs from
 * in.mpathd into `ifinfop' before the current time becomes `endtp'.  Returns
 * an IPMP error code.  On failure, `ifinfop' will have its original contents.
 */
static int
ipmp_readifinfo_lists(ipmp_state_t *statep, ipmp_ifinfo_t *ifinfop,
    const struct timeval *endtp)
{
        int retval;
        ipmp_addrlist_t *tlist4p, *tlist6p;

        retval = ipmp_readinfo(statep, IPMP_ADDRLIST, (void **)&tlist4p, endtp);
        if (retval != IPMP_SUCCESS)
                return (retval);

        retval = ipmp_readinfo(statep, IPMP_ADDRLIST, (void **)&tlist6p, endtp);
        if (retval != IPMP_SUCCESS) {
                ipmp_freeaddrlist(tlist4p);
                return (retval);
        }

        ifinfop->if_targinfo4.it_targlistp = tlist4p;
        ifinfop->if_targinfo6.it_targlistp = tlist6p;
        return (IPMP_SUCCESS);
}

/*
 * Complete the query operation started in ipmp_sendquery().  The interface is
 * designed to be easy to use in the `return' statement of a function, and
 * thus returns the passed in `retval' and preserves `errno'.
 */
static int
ipmp_querydone(ipmp_state_t *statep, int retval)
{
        int error = errno;

        (void) close(statep->st_fd);
        statep->st_fd = -1;
        errno = error;
        return (retval);
}

/*
 * Using `handle', get the group list and store the results in a dynamically
 * allocated buffer pointed to by `*grlistpp'.  Returns an IPMP error code.
 */
int
ipmp_getgrouplist(ipmp_handle_t handle, ipmp_grouplist_t **grlistpp)
{
        ipmp_state_t    *statep = handle;
        struct timeval  end;
        int             retval;

        if (statep->st_snap != NULL) {
                *grlistpp = ipmp_grouplist_clone(statep->st_snap->sn_grlistp);
                return (*grlistpp != NULL ? IPMP_SUCCESS : IPMP_ENOMEM);
        }

        retval = ipmp_sendquery(statep, IPMP_GROUPLIST, NULL, NULL, &end);
        if (retval != IPMP_SUCCESS)
                return (retval);

        retval = ipmp_readinfo(statep, IPMP_GROUPLIST, (void **)grlistpp, &end);
        return (ipmp_querydone(statep, retval));
}

/*
 * Free the group list pointed to by `grlistp'.
 */
void
ipmp_freegrouplist(ipmp_grouplist_t *grlistp)
{
        free(grlistp);
}

/*
 * Convert a ipmp_groupinfo_xfer_t used for communication with in.mpathd
 * into a newly allocated ipmp_groupinfo_t. Free the ipmp_groupinfo_xfer_t,
 * regardless of failure.
 */
static ipmp_groupinfo_t *
ipmp_convertgroupinfo(ipmp_groupinfo_xfer_t *grxferp)
{
        ipmp_groupinfo_t *grinfop;

        grinfop = calloc(1, sizeof (ipmp_groupinfo_t));
        if (grinfop != NULL) {
                memcpy(grinfop->gr_name, grxferp->grx_name,
                    sizeof (grinfop->gr_name));
                grinfop->gr_sig = grxferp->grx_sig;
                grinfop->gr_state = grxferp->grx_state;
                memcpy(grinfop->gr_ifname, grxferp->grx_ifname,
                    sizeof (grinfop->gr_ifname));
                memcpy(grinfop->gr_m4ifname, grxferp->grx_m4ifname,
                    sizeof (grinfop->gr_m4ifname));
                memcpy(grinfop->gr_m6ifname, grxferp->grx_m6ifname,
                    sizeof (grinfop->gr_m6ifname));
                memcpy(grinfop->gr_bcifname, grxferp->grx_bcifname,
                    sizeof (grinfop->gr_bcifname));
                grinfop->gr_fdt = grxferp->grx_fdt;
        }

        free(grxferp);

        return (grinfop);
}
/*
 * Using `handle', get the group information associated with group `name' and
 * store the results in a dynamically allocated buffer pointed to by
 * `*grinfopp'.  Returns an IPMP error code.
 */
int
ipmp_getgroupinfo(ipmp_handle_t handle, const char *name,
    ipmp_groupinfo_t **grinfopp)
{
        ipmp_state_t    *statep = handle;
        int             retval;
        struct timeval  end;
        ipmp_groupinfo_t *grinfop;
        ipmp_groupinfo_xfer_t *grxferp;

        if (statep->st_snap != NULL) {
                grinfop = ipmp_snap_getgroupinfo(statep->st_snap, name);
                if (grinfop == NULL)
                        return (IPMP_EUNKGROUP);

                *grinfopp = ipmp_groupinfo_clone(grinfop);
                return (*grinfopp != NULL ? IPMP_SUCCESS : IPMP_ENOMEM);
        }

        retval = ipmp_sendquery(statep, IPMP_GROUPINFO, name, NULL, &end);
        if (retval != IPMP_SUCCESS)
                return (retval);

        retval = ipmp_readinfo(statep, IPMP_GROUPINFO, (void **)&grxferp, &end);
        if (retval != IPMP_SUCCESS)
                return (ipmp_querydone(statep, retval));

        *grinfopp = ipmp_convertgroupinfo(grxferp);
        if (*grinfopp == NULL)
                return (ipmp_querydone(statep, IPMP_ENOMEM));

        retval = ipmp_readgroupinfo_lists(statep, *grinfopp, &end);
        if (retval != IPMP_SUCCESS)
                free(*grinfopp);

        return (ipmp_querydone(statep, retval));
}

/*
 * Free the group information pointed to by `grinfop'.
 */
void
ipmp_freegroupinfo(ipmp_groupinfo_t *grinfop)
{
        ipmp_freeaddrlist(grinfop->gr_adlistp);
        ipmp_freeiflist(grinfop->gr_iflistp);
        free(grinfop);
}

/*
 * Convert a ipmp_ifinfo_xfer_t used for communication with in.mpathd
 * into a newly allocated ipmp_ifinfo_t. Free the ipmp_ifinfo_xfer_t,
 * regardless of failure.
 */
static ipmp_ifinfo_t *
ipmp_convertifinfo(ipmp_ifinfo_xfer_t *ifxferp)
{
        ipmp_ifinfo_t *ifinfop;

        ifinfop = calloc(1, sizeof (ipmp_ifinfo_t));
        if (ifinfop != NULL) {
                memcpy(ifinfop->if_name, ifxferp->ifx_name,
                    sizeof (ifinfop->if_name));
                memcpy(ifinfop->if_group, ifxferp->ifx_group,
                    sizeof (ifinfop->if_group));
                ifinfop->if_state = ifxferp->ifx_state;
                ifinfop->if_type = ifxferp->ifx_type;
                ifinfop->if_linkstate = ifxferp->ifx_linkstate;
                ifinfop->if_probestate = ifxferp->ifx_probestate;
                ifinfop->if_flags = ifxferp->ifx_flags;
                memcpy(ifinfop->if_targinfo4.it_name,
                    ifxferp->ifx_targinfo4.itx_name,
                    sizeof (ifinfop->if_targinfo4.it_name));
                ifinfop->if_targinfo4.it_testaddr =
                    ifxferp->ifx_targinfo4.itx_testaddr;
                ifinfop->if_targinfo4.it_targmode =
                    ifxferp->ifx_targinfo4.itx_targmode;
                memcpy(ifinfop->if_targinfo6.it_name,
                    ifxferp->ifx_targinfo6.itx_name,
                    sizeof (ifinfop->if_targinfo6.it_name));
                ifinfop->if_targinfo6.it_testaddr =
                    ifxferp->ifx_targinfo6.itx_testaddr;
                ifinfop->if_targinfo6.it_targmode =
                    ifxferp->ifx_targinfo6.itx_targmode;
        }

        free(ifxferp);

        return (ifinfop);
}

/*
 * Using `handle', get the interface information associated with interface
 * `name' and store the results in a dynamically allocated buffer pointed to
 * by `*ifinfopp'.  Returns an IPMP error code.
 */
int
ipmp_getifinfo(ipmp_handle_t handle, const char *name, ipmp_ifinfo_t **ifinfopp)
{
        ipmp_state_t    *statep = handle;
        ipmp_ifinfo_t   *ifinfop;
        ipmp_ifinfo_xfer_t *ifxferp;
        int             retval;
        struct timeval  end;

        if (statep->st_snap != NULL) {
                ifinfop = ipmp_snap_getifinfo(statep->st_snap, name);
                if (ifinfop == NULL)
                        return (IPMP_EUNKIF);

                *ifinfopp = ipmp_ifinfo_clone(ifinfop);
                return (*ifinfopp != NULL ? IPMP_SUCCESS : IPMP_ENOMEM);
        }

        retval = ipmp_sendquery(statep, IPMP_IFINFO, name, NULL, &end);
        if (retval != IPMP_SUCCESS)
                return (retval);

        retval = ipmp_readinfo(statep, IPMP_IFINFO, (void **)&ifxferp, &end);
        if (retval != IPMP_SUCCESS)
                return (ipmp_querydone(statep, retval));

        *ifinfopp = ipmp_convertifinfo(ifxferp);
        if (*ifinfopp == NULL)
                return (ipmp_querydone(statep, IPMP_ENOMEM));

        retval = ipmp_readifinfo_lists(statep, *ifinfopp, &end);
        if (retval != IPMP_SUCCESS)
                free(*ifinfopp);

        return (ipmp_querydone(statep, retval));
}

/*
 * Free the interface information pointed to by `ifinfop'.
 */
void
ipmp_freeifinfo(ipmp_ifinfo_t *ifinfop)
{
        ipmp_freeaddrlist(ifinfop->if_targinfo4.it_targlistp);
        ipmp_freeaddrlist(ifinfop->if_targinfo6.it_targlistp);
        free(ifinfop);
}

/*
 * Using `handle', get the address information associated with address `addrp'
 * on group `grname' and store the results in a dynamically allocated buffer
 * pointed to by `*adinfopp'.  Returns an IPMP error code.
 */
int
ipmp_getaddrinfo(ipmp_handle_t handle, const char *grname,
    struct sockaddr_storage *addrp, ipmp_addrinfo_t **adinfopp)
{
        ipmp_state_t    *statep = handle;
        ipmp_addrinfo_t *adinfop;
        int             retval;
        struct timeval  end;

        if (statep->st_snap != NULL) {
                adinfop = ipmp_snap_getaddrinfo(statep->st_snap, grname, addrp);
                if (adinfop == NULL)
                        return (IPMP_EUNKADDR);

                *adinfopp = ipmp_addrinfo_clone(adinfop);
                return (*adinfopp != NULL ? IPMP_SUCCESS : IPMP_ENOMEM);
        }

        retval = ipmp_sendquery(statep, IPMP_ADDRINFO, grname, addrp, &end);
        if (retval != IPMP_SUCCESS)
                return (retval);

        retval = ipmp_readinfo(statep, IPMP_ADDRINFO, (void **)adinfopp, &end);
        return (ipmp_querydone(statep, retval));
}

/*
 * Free the address information pointed to by `adinfop'.
 */
void
ipmp_freeaddrinfo(ipmp_addrinfo_t *adinfop)
{
        free(adinfop);
}

/*
 * Check if `buf' has a NUL byte in its first `bufsize' bytes.
 */
static boolean_t
hasnulbyte(const char *buf, size_t bufsize)
{
        while (bufsize-- > 0) {
                if (buf[bufsize] == '\0')
                        return (B_TRUE);
        }
        return (B_FALSE);
}

/*
 * Check that the TLV triplet named by `type', `len' and `value' is correctly
 * formed.
 */
static boolean_t
ipmp_checktlv(ipmp_infotype_t type, size_t len, void *value)
{
        ipmp_iflist_t           *iflistp;
        ipmp_ifinfo_xfer_t      *ifxferp;
        ipmp_grouplist_t        *grlistp;
        ipmp_groupinfo_xfer_t   *grxferp;
        ipmp_addrlist_t         *adlistp;
        unsigned int            i;

        switch (type) {
        case IPMP_ADDRINFO:
                if (len != sizeof (ipmp_addrinfo_t))
                        return (B_FALSE);
                break;

        case IPMP_ADDRLIST:
                adlistp = (ipmp_addrlist_t *)value;
                if (len < IPMP_ADDRLIST_SIZE(0) ||
                    len < IPMP_ADDRLIST_SIZE(adlistp->al_naddr))
                        return (B_FALSE);
                break;

        case IPMP_IFLIST:
                iflistp = (ipmp_iflist_t *)value;
                if (len < IPMP_IFLIST_SIZE(0) ||
                    len < IPMP_IFLIST_SIZE(iflistp->il_nif))
                        return (B_FALSE);

                for (i = 0; i < iflistp->il_nif; i++)
                        if (!hasnulbyte(iflistp->il_ifs[i], LIFNAMSIZ))
                                return (B_FALSE);
                break;

        case IPMP_IFINFO:
                ifxferp = (ipmp_ifinfo_xfer_t *)value;
                if (len != sizeof (ipmp_ifinfo_xfer_t))
                        return (B_FALSE);

                if (!hasnulbyte(ifxferp->ifx_name, LIFNAMSIZ) ||
                    !hasnulbyte(ifxferp->ifx_group, LIFGRNAMSIZ))
                        return (B_FALSE);
                break;

        case IPMP_GROUPLIST:
                grlistp = (ipmp_grouplist_t *)value;
                if (len < IPMP_GROUPLIST_SIZE(0) ||
                    len < IPMP_GROUPLIST_SIZE(grlistp->gl_ngroup))
                        return (B_FALSE);

                for (i = 0; i < grlistp->gl_ngroup; i++)
                        if (!hasnulbyte(grlistp->gl_groups[i], LIFGRNAMSIZ))
                                return (B_FALSE);
                break;

        case IPMP_GROUPINFO:
                grxferp = (ipmp_groupinfo_xfer_t *)value;
                if (len != sizeof (ipmp_groupinfo_xfer_t))
                        return (B_FALSE);

                if (!hasnulbyte(grxferp->grx_name, LIFGRNAMSIZ))
                        return (B_FALSE);
                break;

        case IPMP_ADDRCNT:
        case IPMP_GROUPCNT:
        case IPMP_IFCNT:
                if (len != sizeof (uint32_t))
                        return (B_FALSE);
                break;

        default:
                return (B_FALSE);
        }

        return (B_TRUE);
}

/*
 * Create a group list; arguments match ipmp_grouplist_t fields.  Returns a
 * pointer to the new group list on success, or NULL on failure.
 */
ipmp_grouplist_t *
ipmp_grouplist_create(uint64_t sig, unsigned int ngroup,
    char (*groups)[LIFGRNAMSIZ])
{
        unsigned int i;
        ipmp_grouplist_t *grlistp;

        grlistp = malloc(IPMP_GROUPLIST_SIZE(ngroup));
        if (grlistp == NULL)
                return (NULL);

        grlistp->gl_sig = sig;
        grlistp->gl_ngroup = ngroup;
        for (i = 0; i < ngroup; i++)
                (void) strlcpy(grlistp->gl_groups[i], groups[i], LIFGRNAMSIZ);

        return (grlistp);
}

/*
 * Clone the group list named by `grlistp'.  Returns a pointer to the clone on
 * success, or NULL on failure.
 */
ipmp_grouplist_t *
ipmp_grouplist_clone(ipmp_grouplist_t *grlistp)
{
        return (ipmp_grouplist_create(grlistp->gl_sig, grlistp->gl_ngroup,
            grlistp->gl_groups));
}

/*
 * Create target information; arguments match ipmp_targinfo_t fields.  Returns
 * a pointer to the new target info on success, or NULL on failure.
 */
ipmp_targinfo_t *
ipmp_targinfo_create(const char *name, struct sockaddr_storage *testaddrp,
    ipmp_if_targmode_t targmode, uint_t ntarg, struct sockaddr_storage *targs)
{
        ipmp_targinfo_t *targinfop;

        targinfop = malloc(sizeof (ipmp_targinfo_t));
        if (targinfop == NULL)
                return (NULL);

        targinfop->it_testaddr = *testaddrp;
        targinfop->it_targmode = targmode;
        targinfop->it_targlistp = ipmp_addrlist_create(ntarg, targs);
        if (targinfop->it_targlistp == NULL) {
                ipmp_freetarginfo(targinfop);
                return (NULL);
        }
        (void) strlcpy(targinfop->it_name, name, LIFNAMSIZ);

        return (targinfop);
}

/*
 * Free the target information pointed to by `targinfop'.
 */
void
ipmp_freetarginfo(ipmp_targinfo_t *targinfop)
{
        free(targinfop->it_targlistp);
        free(targinfop);
}

/*
 * Create an interface list; arguments match ipmp_iflist_t fields.  Returns a
 * pointer to the new interface list on success, or NULL on failure.
 */
static ipmp_iflist_t *
ipmp_iflist_create(uint_t nif, char (*ifs)[LIFNAMSIZ])
{
        unsigned int i;
        ipmp_iflist_t *iflistp;

        iflistp = malloc(IPMP_IFLIST_SIZE(nif));
        if (iflistp == NULL)
                return (NULL);

        iflistp->il_nif = nif;
        for (i = 0; i < nif; i++)
                (void) strlcpy(iflistp->il_ifs[i], ifs[i], LIFNAMSIZ);

        return (iflistp);
}

/*
 * Free the interface list pointed to by `iflistp'.
 */
static void
ipmp_freeiflist(ipmp_iflist_t *iflistp)
{
        free(iflistp);
}

/*
 * Create an interface; arguments match ipmp_ifinfo_t fields.  Returns a
 * pointer to the new interface on success, or NULL on failure.
 */
ipmp_ifinfo_t *
ipmp_ifinfo_create(const char *name, const char *group, ipmp_if_state_t state,
    ipmp_if_type_t type, ipmp_if_linkstate_t linkstate,
    ipmp_if_probestate_t probestate, ipmp_if_flags_t flags,
    ipmp_targinfo_t *targinfo4p, ipmp_targinfo_t *targinfo6p)
{
        ipmp_ifinfo_t *ifinfop;

        ifinfop = malloc(sizeof (ipmp_ifinfo_t));
        if (ifinfop == NULL)
                return (NULL);

        (void) strlcpy(ifinfop->if_name, name, LIFNAMSIZ);
        (void) strlcpy(ifinfop->if_group, group, LIFGRNAMSIZ);

        ifinfop->if_state       = state;
        ifinfop->if_type        = type;
        ifinfop->if_linkstate   = linkstate;
        ifinfop->if_probestate  = probestate;
        ifinfop->if_flags       = flags;
        ifinfop->if_targinfo4   = *targinfo4p;
        ifinfop->if_targinfo6   = *targinfo6p;

        ifinfop->if_targinfo4.it_targlistp =
            ipmp_addrlist_clone(targinfo4p->it_targlistp);
        ifinfop->if_targinfo6.it_targlistp =
            ipmp_addrlist_clone(targinfo6p->it_targlistp);

        if (ifinfop->if_targinfo4.it_targlistp == NULL ||
            ifinfop->if_targinfo6.it_targlistp == NULL) {
                ipmp_freeifinfo(ifinfop);
                return (NULL);
        }

        return (ifinfop);
}

/*
 * Clone the interface information named by `ifinfop'.  Returns a pointer to
 * the clone on success, or NULL on failure.
 */
ipmp_ifinfo_t *
ipmp_ifinfo_clone(ipmp_ifinfo_t *ifinfop)
{
        return (ipmp_ifinfo_create(ifinfop->if_name, ifinfop->if_group,
            ifinfop->if_state, ifinfop->if_type, ifinfop->if_linkstate,
            ifinfop->if_probestate, ifinfop->if_flags, &ifinfop->if_targinfo4,
            &ifinfop->if_targinfo6));
}

/*
 * Create a group; arguments match ipmp_groupinfo_t fields.  Returns a pointer
 * to the new group on success, or NULL on failure.
 */
ipmp_groupinfo_t *
ipmp_groupinfo_create(const char *name, uint64_t sig, uint_t fdt,
    ipmp_group_state_t state, uint_t nif, char (*ifs)[LIFNAMSIZ],
    const char *grifname, const char *m4ifname, const char *m6ifname,
    const char *bcifname, uint_t naddr, struct sockaddr_storage *addrs)
{
        ipmp_groupinfo_t *grinfop;

        grinfop = malloc(sizeof (ipmp_groupinfo_t));
        if (grinfop == NULL)
                return (NULL);

        grinfop->gr_sig = sig;
        grinfop->gr_fdt = fdt;
        grinfop->gr_state = state;
        grinfop->gr_iflistp = ipmp_iflist_create(nif, ifs);
        grinfop->gr_adlistp = ipmp_addrlist_create(naddr, addrs);
        if (grinfop->gr_iflistp == NULL || grinfop->gr_adlistp == NULL) {
                ipmp_freegroupinfo(grinfop);
                return (NULL);
        }
        (void) strlcpy(grinfop->gr_name, name, LIFGRNAMSIZ);
        (void) strlcpy(grinfop->gr_ifname, grifname, LIFNAMSIZ);
        (void) strlcpy(grinfop->gr_m4ifname, m4ifname, LIFNAMSIZ);
        (void) strlcpy(grinfop->gr_m6ifname, m6ifname, LIFNAMSIZ);
        (void) strlcpy(grinfop->gr_bcifname, bcifname, LIFNAMSIZ);

        return (grinfop);
}

/*
 * Clone the group information named by `grinfop'.  Returns a pointer to
 * the clone on success, or NULL on failure.
 */
ipmp_groupinfo_t *
ipmp_groupinfo_clone(ipmp_groupinfo_t *grinfop)
{
        ipmp_addrlist_t *adlistp = grinfop->gr_adlistp;

        return (ipmp_groupinfo_create(grinfop->gr_name, grinfop->gr_sig,
            grinfop->gr_fdt, grinfop->gr_state, grinfop->gr_iflistp->il_nif,
            grinfop->gr_iflistp->il_ifs, grinfop->gr_ifname,
            grinfop->gr_m4ifname, grinfop->gr_m6ifname, grinfop->gr_bcifname,
            adlistp->al_naddr, adlistp->al_addrs));
}

/*
 * Create an address list; arguments match ipmp_addrlist_t fields.  Returns
 * a pointer to the new address list on success, or NULL on failure.
 */
static ipmp_addrlist_t *
ipmp_addrlist_create(uint_t naddr, struct sockaddr_storage *addrs)
{
        unsigned int i;
        ipmp_addrlist_t *adlistp;

        adlistp = malloc(IPMP_ADDRLIST_SIZE(naddr));
        if (adlistp == NULL)
                return (NULL);

        adlistp->al_naddr = naddr;
        for (i = 0; i < naddr; i++)
                adlistp->al_addrs[i] = addrs[i];

        return (adlistp);
}

/*
 * Clone the address list named by `adlistp'.  Returns a pointer to the clone
 * on success, or NULL on failure.
 */
static ipmp_addrlist_t *
ipmp_addrlist_clone(ipmp_addrlist_t *adlistp)
{
        return (ipmp_addrlist_create(adlistp->al_naddr, adlistp->al_addrs));
}

/*
 * Free the address list pointed to by `adlistp'.
 */
static void
ipmp_freeaddrlist(ipmp_addrlist_t *adlistp)
{
        free(adlistp);
}

/*
 * Create an address; arguments match ipmp_addrinfo_t fields.  Returns a
 * pointer to the new address on success, or NULL on failure.
 */
ipmp_addrinfo_t *
ipmp_addrinfo_create(struct sockaddr_storage *addrp, ipmp_addr_state_t state,
    const char *group, const char *binding)
{
        ipmp_addrinfo_t *adinfop;

        adinfop = malloc(sizeof (ipmp_addrinfo_t));
        if (adinfop == NULL)
                return (NULL);

        adinfop->ad_addr = *addrp;
        adinfop->ad_state = state;
        (void) strlcpy(adinfop->ad_group, group, LIFGRNAMSIZ);
        (void) strlcpy(adinfop->ad_binding, binding, LIFNAMSIZ);

        return (adinfop);
}

/*
 * Clone the address information named by `adinfop'.  Returns a pointer to
 * the clone on success, or NULL on failure.
 */
ipmp_addrinfo_t *
ipmp_addrinfo_clone(ipmp_addrinfo_t *adinfop)
{
        return (ipmp_addrinfo_create(&adinfop->ad_addr, adinfop->ad_state,
            adinfop->ad_group, adinfop->ad_binding));
}

/*
 * Set the query context associated with `handle' to `qcontext', which must be
 * either IPMP_QCONTEXT_LIVE or IPMP_QCONTEXT_SNAP.  Upon success, any
 * previous snapshot associated with `handle' is discarded.  Returns an IPMP
 * error code.
 */
int
ipmp_setqcontext(ipmp_handle_t handle, ipmp_qcontext_t qcontext)
{
        ipmp_state_t    *statep = handle;
        ipmp_snap_t     *snap;
        int             retval;

        switch (qcontext) {
        case IPMP_QCONTEXT_LIVE:
                snap = NULL;
                break;

        case IPMP_QCONTEXT_SNAP:
                retval = ipmp_snap_take(statep, &snap);
                if (retval != IPMP_SUCCESS)
                        return (retval);
                break;

        default:
                return (IPMP_EINVAL);
        }

        if (statep->st_snap != NULL)
                ipmp_snap_free(statep->st_snap);
        statep->st_snap = snap;

        return (IPMP_SUCCESS);
}

/*
 * Create an empty snapshot.  Returns a pointer to the snapshot on success,
 * or NULL on failure.
 */
ipmp_snap_t *
ipmp_snap_create(void)
{
        ipmp_snap_t *snap;

        snap = malloc(sizeof (ipmp_snap_t));
        if (snap == NULL)
                return (NULL);

        snap->sn_grlistp = NULL;
        snap->sn_grinfolistp = NULL;
        snap->sn_ifinfolistp = NULL;
        snap->sn_adinfolistp = NULL;
        snap->sn_ngroup = 0;
        snap->sn_nif = 0;
        snap->sn_naddr = 0;

        return (snap);
}

/*
 * Free all of the resources associated with snapshot `snap'.
 */
void
ipmp_snap_free(ipmp_snap_t *snap)
{
        ipmp_ifinfolist_t       *iflp, *ifnext;
        ipmp_addrinfolist_t     *adlp, *adnext;
        ipmp_groupinfolist_t    *grlp, *grnext;

        ipmp_freegrouplist(snap->sn_grlistp);

        for (grlp = snap->sn_grinfolistp; grlp != NULL; grlp = grnext) {
                grnext = grlp->grl_next;
                ipmp_freegroupinfo(grlp->grl_grinfop);
                free(grlp);
        }

        for (iflp = snap->sn_ifinfolistp; iflp != NULL; iflp = ifnext) {
                ifnext = iflp->ifl_next;
                ipmp_freeifinfo(iflp->ifl_ifinfop);
                free(iflp);
        }

        for (adlp = snap->sn_adinfolistp; adlp != NULL; adlp = adnext) {
                adnext = adlp->adl_next;
                ipmp_freeaddrinfo(adlp->adl_adinfop);
                free(adlp);
        }

        free(snap);
}

/*
 * Add the group information in `grinfop' to the snapshot named by `snap'.
 * Returns an IPMP error code.
 */
int
ipmp_snap_addgroupinfo(ipmp_snap_t *snap, ipmp_groupinfo_t *grinfop)
{
        ipmp_groupinfolist_t *grlp;

        /*
         * If the information for this group is already in the snapshot,
         * in.mpathd is broken.
         */
        if (ipmp_snap_getgroupinfo(snap, grinfop->gr_name) != NULL)
                return (IPMP_EPROTO);

        grlp = malloc(sizeof (ipmp_groupinfolist_t));
        if (grlp == NULL)
                return (IPMP_ENOMEM);

        grlp->grl_grinfop = grinfop;
        grlp->grl_next = snap->sn_grinfolistp;
        snap->sn_grinfolistp = grlp;
        snap->sn_ngroup++;

        return (IPMP_SUCCESS);
}

/*
 * Add the interface information in `ifinfop' to the snapshot named by `snap'.
 * Returns an IPMP error code.
 */
int
ipmp_snap_addifinfo(ipmp_snap_t *snap, ipmp_ifinfo_t *ifinfop)
{
        ipmp_ifinfolist_t *iflp;

        /*
         * If the information for this interface is already in the snapshot,
         * in.mpathd is broken.
         */
        if (ipmp_snap_getifinfo(snap, ifinfop->if_name) != NULL)
                return (IPMP_EPROTO);

        iflp = malloc(sizeof (ipmp_ifinfolist_t));
        if (iflp == NULL)
                return (IPMP_ENOMEM);

        iflp->ifl_ifinfop = ifinfop;
        iflp->ifl_next = snap->sn_ifinfolistp;
        snap->sn_ifinfolistp = iflp;
        snap->sn_nif++;

        return (IPMP_SUCCESS);
}

/*
 * Add the address information in `adinfop' to the snapshot named by `snap'.
 * Returns an IPMP error code.
 */
int
ipmp_snap_addaddrinfo(ipmp_snap_t *snap, ipmp_addrinfo_t *adinfop)
{
        ipmp_addrinfolist_t *adlp;

        /*
         * Any duplicate addresses should've already been weeded by in.mpathd.
         */
        if (ipmp_snap_getaddrinfo(snap, adinfop->ad_group,
            &adinfop->ad_addr) != NULL)
                return (IPMP_EPROTO);

        adlp = malloc(sizeof (ipmp_addrinfolist_t));
        if (adlp == NULL)
                return (IPMP_ENOMEM);

        adlp->adl_adinfop = adinfop;
        adlp->adl_next = snap->sn_adinfolistp;
        snap->sn_adinfolistp = adlp;
        snap->sn_naddr++;

        return (IPMP_SUCCESS);
}

/*
 * Retrieve the information for the group `name' in snapshot `snap'.
 * Returns a pointer to the group information on success, or NULL on failure.
 */
static ipmp_groupinfo_t *
ipmp_snap_getgroupinfo(ipmp_snap_t *snap, const char *name)
{
        ipmp_groupinfolist_t *grlp;

        for (grlp = snap->sn_grinfolistp; grlp != NULL; grlp = grlp->grl_next) {
                if (strcmp(grlp->grl_grinfop->gr_name, name) == 0)
                        break;
        }

        return (grlp != NULL ? grlp->grl_grinfop : NULL);
}

/*
 * Retrieve the information for the interface `name' in snapshot `snap'.
 * Returns a pointer to the interface information on success, or NULL on
 * failure.
 */
static ipmp_ifinfo_t *
ipmp_snap_getifinfo(ipmp_snap_t *snap, const char *name)
{
        ipmp_ifinfolist_t *iflp;

        for (iflp = snap->sn_ifinfolistp; iflp != NULL; iflp = iflp->ifl_next) {
                if (strcmp(iflp->ifl_ifinfop->if_name, name) == 0)
                        break;
        }

        return (iflp != NULL ? iflp->ifl_ifinfop : NULL);
}

/*
 * Retrieve the information for the address `addrp' on group `grname' in
 * snapshot `snap'.  Returns a pointer to the address information on success,
 * or NULL on failure.
 */
static ipmp_addrinfo_t *
ipmp_snap_getaddrinfo(ipmp_snap_t *snap, const char *grname,
    struct sockaddr_storage *addrp)
{
        ipmp_addrinfolist_t *adlp;

        for (adlp = snap->sn_adinfolistp; adlp != NULL; adlp = adlp->adl_next) {
                if (strcmp(grname, adlp->adl_adinfop->ad_group) == 0 &&
                    sockaddrcmp(addrp, &adlp->adl_adinfop->ad_addr))
                        break;
        }

        return (adlp != NULL ? adlp->adl_adinfop : NULL);
}

/*
 * Using `statep', take a snapshot of the IPMP subsystem and if successful
 * return it in a dynamically allocated snapshot pointed to by `*snapp'.
 * Returns an IPMP error code.
 */
static int
ipmp_snap_take(ipmp_state_t *statep, ipmp_snap_t **snapp)
{
        uint64_t        naddr, ngroup, nif;
        ipmp_snap_t     *snap;
        ipmp_infotype_t type;
        int             retval;
        size_t          len;
        void            *infop;
        struct timeval  end;

        naddr = ngroup = nif = UINT64_MAX;

        snap = ipmp_snap_create();
        if (snap == NULL)
                return (IPMP_ENOMEM);

        retval = ipmp_sendquery(statep, IPMP_SNAP, NULL, NULL, &end);
        if (retval != IPMP_SUCCESS) {
                ipmp_snap_free(snap);
                return (retval);
        }

        /*
         * Build up our snapshot.  We know there will always be at least four
         * TLVs for IPMP_GROUPLIST, IPMP_IFCNT, IPMP_GROUPCNT, and IPMP_ADDRCNT.
         * If we receive anything illogical (e.g., more than the expected number
         * of interfaces), then bail out.  However, to a large extent we have to
         * trust the information sent by in.mpathd.
         */
        do {
                infop = NULL;
                retval = ipmp_readtlv(statep->st_fd, &type, &len, &infop, &end);
                if (retval != IPMP_SUCCESS)
                        goto fail;

                if (!ipmp_checktlv(type, len, infop)) {
                        retval = IPMP_EPROTO;
                        goto fail;
                }

                switch (type) {
                case IPMP_GROUPLIST:
                        if (snap->sn_grlistp != NULL) {
                                retval = IPMP_EPROTO;
                                break;
                        }
                        snap->sn_grlistp = infop;
                        break;

                case IPMP_IFINFO:
                        if (snap->sn_nif == nif) {
                                retval = IPMP_EPROTO;
                                break;
                        }

                        infop = ipmp_convertifinfo(infop);
                        if (infop == NULL) {
                                retval = IPMP_ENOMEM;
                                break;
                        }

                        /*
                         * Read in V4 and V6 targlist TLVs that follow.
                         */
                        retval = ipmp_readifinfo_lists(statep, infop, &end);
                        if (retval != IPMP_SUCCESS)
                                break;

                        retval = ipmp_snap_addifinfo(snap, infop);
                        if (retval != IPMP_SUCCESS) {
                                ipmp_freeifinfo(infop);
                                infop = NULL;
                        }
                        break;

                case IPMP_ADDRINFO:
                        if (snap->sn_naddr == naddr) {
                                retval = IPMP_EPROTO;
                                break;
                        }

                        retval = ipmp_snap_addaddrinfo(snap, infop);
                        /*
                         * NOTE: since we didn't call ipmp_read*info_lists(),
                         * no need to use ipmp_freeaddrinfo() on failure.
                         */
                        break;

                case IPMP_GROUPINFO:
                        if (snap->sn_ngroup == ngroup) {
                                retval = IPMP_EPROTO;
                                break;
                        }

                        infop = ipmp_convertgroupinfo(infop);
                        if (infop == NULL) {
                                retval = IPMP_ENOMEM;
                                break;
                        }

                        /*
                         * Read in IPMP groupinfo list TLVs that follow.
                         */
                        retval = ipmp_readgroupinfo_lists(statep, infop, &end);
                        if (retval != IPMP_SUCCESS)
                                break;

                        retval = ipmp_snap_addgroupinfo(snap, infop);
                        if (retval != IPMP_SUCCESS) {
                                ipmp_freegroupinfo(infop);
                                infop = NULL;
                        }
                        break;

                case IPMP_ADDRCNT:
                        if (naddr != UINT64_MAX) {
                                retval = IPMP_EPROTO;
                                break;
                        }

                        naddr = *(uint32_t *)infop;
                        break;

                case IPMP_GROUPCNT:
                        if (ngroup != UINT64_MAX) {
                                retval = IPMP_EPROTO;
                                break;
                        }

                        ngroup = *(uint32_t *)infop;
                        break;

                case IPMP_IFCNT:
                        if (nif != UINT64_MAX) {
                                retval = IPMP_EPROTO;
                                break;
                        }

                        nif = *(uint32_t *)infop;
                        break;

                default:
                        retval = IPMP_EPROTO;
                        break;
                }
fail:
                if (retval != IPMP_SUCCESS) {
                        free(infop);
                        ipmp_snap_free(snap);
                        return (ipmp_querydone(statep, retval));
                }
        } while (snap->sn_grlistp == NULL || snap->sn_nif < nif ||
            snap->sn_ngroup < ngroup || snap->sn_naddr < naddr);

        *snapp = snap;
        return (ipmp_querydone(statep, IPMP_SUCCESS));
}