root/usr/src/lib/libnsl/rpc/rpcb_clnt.c
/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License, Version 1.0 only
 * (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 2015 Nexenta Systems, Inc.  All rights reserved.
 */

/*
 * Copyright 2014 Gary Mills
 * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

/* Copyright (c) 1983, 1984, 1985, 1986, 1987, 1988, 1989 AT&T */
/* All Rights Reserved */
/*
 * Portions of this source code were derived from Berkeley
 * 4.3 BSD under license from the Regents of the University of
 * California.
 */

/*
 * interface to rpcbind rpc service.
 */

#include "mt.h"
#include "rpc_mt.h"
#include <assert.h>
#include <rpc/rpc.h>
#include <rpc/rpcb_prot.h>
#include <netconfig.h>
#include <netdir.h>
#include <netdb.h>
#include <rpc/nettype.h>
#include <syslog.h>
#ifdef PORTMAP
#include <netinet/in.h>         /* FOR IPPROTO_TCP/UDP definitions */
#include <rpc/pmap_prot.h>
#endif
#include <errno.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>

static struct timeval tottimeout = { 60, 0 };
static const struct timeval rmttimeout = { 3, 0 };
static struct timeval rpcbrmttime = { 15, 0 };

extern bool_t xdr_wrapstring(XDR *, char **);

static const char nullstring[] = "\000";

extern CLIENT *_clnt_tli_create_timed(int, const struct netconfig *,
                        struct netbuf *, rpcprog_t, rpcvers_t, uint_t, uint_t,
                        const struct timeval *);

static CLIENT *_getclnthandle_timed(char *, struct netconfig *, char **,
                        struct timeval *);


/*
 * The life time of a cached entry should not exceed 5 minutes
 * since automountd attempts an unmount every 5 minutes.
 * It is arbitrarily set a little lower (3 min = 180 sec)
 * to reduce the time during which an entry is stale.
 */
#define CACHE_TTL 180
#define CACHESIZE 6

struct address_cache {
        char *ac_host;
        char *ac_netid;
        char *ac_uaddr;
        struct netbuf *ac_taddr;
        struct address_cache *ac_next;
        time_t ac_maxtime;
};

static struct address_cache *front;
static int cachesize;

extern int lowvers;
extern int authdes_cachesz;
/*
 * This routine adjusts the timeout used for calls to the remote rpcbind.
 * Also, this routine can be used to set the use of portmapper version 2
 * only when doing rpc_broadcasts
 * These are private routines that may not be provided in future releases.
 */
bool_t
__rpc_control(int request, void *info)
{
        switch (request) {
        case CLCR_GET_RPCB_TIMEOUT:
                *(struct timeval *)info = tottimeout;
                break;
        case CLCR_SET_RPCB_TIMEOUT:
                tottimeout = *(struct timeval *)info;
                break;
        case CLCR_GET_LOWVERS:
                *(int *)info = lowvers;
                break;
        case CLCR_SET_LOWVERS:
                lowvers = *(int *)info;
                break;
        case CLCR_GET_RPCB_RMTTIME:
                *(struct timeval *)info = rpcbrmttime;
                break;
        case CLCR_SET_RPCB_RMTTIME:
                rpcbrmttime = *(struct timeval *)info;
                break;
        case CLCR_GET_CRED_CACHE_SZ:
                *(int *)info = authdes_cachesz;
                break;
        case CLCR_SET_CRED_CACHE_SZ:
                authdes_cachesz = *(int *)info;
                break;
        default:
                return (FALSE);
        }
        return (TRUE);
}

/*
 *      It might seem that a reader/writer lock would be more reasonable here.
 *      However because getclnthandle(), the only user of the cache functions,
 *      may do a delete_cache() operation if a check_cache() fails to return an
 *      address useful to clnt_tli_create(), we may as well use a mutex.
 */
/*
 * As it turns out, if the cache lock is *not* a reader/writer lock, we will
 * block all clnt_create's if we are trying to connect to a host that's down,
 * since the lock will be held all during that time.
 */
extern rwlock_t rpcbaddr_cache_lock;

/*
 * The routines check_cache(), add_cache(), delete_cache() manage the
 * cache of rpcbind addresses for (host, netid).
 */

static struct address_cache *
check_cache(char *host, char *netid)
{
        struct address_cache *cptr;

        /* READ LOCK HELD ON ENTRY: rpcbaddr_cache_lock */

        assert(RW_READ_HELD(&rpcbaddr_cache_lock));
        for (cptr = front; cptr != NULL; cptr = cptr->ac_next) {
                if ((strcmp(cptr->ac_host, host) == 0) &&
                    (strcmp(cptr->ac_netid, netid) == 0) &&
                    (time(NULL) <= cptr->ac_maxtime)) {
                        return (cptr);
                }
        }
        return (NULL);
}

static void
delete_cache(struct netbuf *addr)
{
        struct address_cache *cptr, *prevptr = NULL;

        /* WRITE LOCK HELD ON ENTRY: rpcbaddr_cache_lock */
        assert(RW_WRITE_HELD(&rpcbaddr_cache_lock));
        for (cptr = front; cptr != NULL; cptr = cptr->ac_next) {
                if (!memcmp(cptr->ac_taddr->buf, addr->buf, addr->len)) {
                        free(cptr->ac_host);
                        free(cptr->ac_netid);
                        free(cptr->ac_taddr->buf);
                        free(cptr->ac_taddr);
                        if (cptr->ac_uaddr)
                                free(cptr->ac_uaddr);
                        if (prevptr)
                                prevptr->ac_next = cptr->ac_next;
                        else
                                front = cptr->ac_next;
                        free(cptr);
                        cachesize--;
                        break;
                }
                prevptr = cptr;
        }
}

static void
add_cache(char *host, char *netid, struct netbuf *taddr, char *uaddr)
{
        struct address_cache  *ad_cache, *cptr, *prevptr;

        ad_cache = malloc(sizeof (struct address_cache));
        if (!ad_cache) {
                goto memerr;
        }
        ad_cache->ac_maxtime = time(NULL) + CACHE_TTL;
        ad_cache->ac_host = strdup(host);
        ad_cache->ac_netid = strdup(netid);
        ad_cache->ac_uaddr = uaddr ? strdup(uaddr) : NULL;
        ad_cache->ac_taddr = malloc(sizeof (struct netbuf));
        if (!ad_cache->ac_host || !ad_cache->ac_netid || !ad_cache->ac_taddr ||
            (uaddr && !ad_cache->ac_uaddr)) {
                goto memerr1;
        }

        ad_cache->ac_taddr->len = ad_cache->ac_taddr->maxlen = taddr->len;
        ad_cache->ac_taddr->buf = malloc(taddr->len);
        if (ad_cache->ac_taddr->buf == NULL) {
                goto memerr1;
        }

        (void) memcpy(ad_cache->ac_taddr->buf, taddr->buf, taddr->len);

/* VARIABLES PROTECTED BY rpcbaddr_cache_lock:  cptr */

        (void) rw_wrlock(&rpcbaddr_cache_lock);
        if (cachesize < CACHESIZE) {
                ad_cache->ac_next = front;
                front = ad_cache;
                cachesize++;
        } else {
                /* Free the last entry */
                cptr = front;
                prevptr = NULL;
                while (cptr->ac_next) {
                        prevptr = cptr;
                        cptr = cptr->ac_next;
                }

                free(cptr->ac_host);
                free(cptr->ac_netid);
                free(cptr->ac_taddr->buf);
                free(cptr->ac_taddr);
                if (cptr->ac_uaddr)
                        free(cptr->ac_uaddr);

                if (prevptr) {
                        prevptr->ac_next = NULL;
                        ad_cache->ac_next = front;
                        front = ad_cache;
                } else {
                        front = ad_cache;
                        ad_cache->ac_next = NULL;
                }
                free(cptr);
        }
        (void) rw_unlock(&rpcbaddr_cache_lock);
        return;
memerr1:
        if (ad_cache->ac_host)
                free(ad_cache->ac_host);
        if (ad_cache->ac_netid)
                free(ad_cache->ac_netid);
        if (ad_cache->ac_uaddr)
                free(ad_cache->ac_uaddr);
        if (ad_cache->ac_taddr)
                free(ad_cache->ac_taddr);
        free(ad_cache);
memerr:
        syslog(LOG_ERR, "add_cache : out of memory.");
}

/*
 * This routine will return a client handle that is connected to the
 * rpcbind. Returns NULL on error and free's everything.
 */
static CLIENT *
getclnthandle(char *host, struct netconfig *nconf, char **targaddr)
{
        return (_getclnthandle_timed(host, nconf, targaddr, NULL));
}

/*
 * Same as getclnthandle() except it takes an extra timeout argument.
 * This is for bug 4049792: clnt_create_timed does not timeout.
 *
 * If tp is NULL, use default timeout to get a client handle.
 */
static CLIENT *
_getclnthandle_timed(char *host, struct netconfig *nconf, char **targaddr,
                                                        struct timeval *tp)
{
        CLIENT *client = NULL;
        struct netbuf *addr;
        struct netbuf addr_to_delete;
        struct nd_addrlist *nas;
        struct nd_hostserv rpcbind_hs;
        struct address_cache *ad_cache;
        char *tmpaddr;
        int neterr;
        int j;

/* VARIABLES PROTECTED BY rpcbaddr_cache_lock:  ad_cache */

        /* Get the address of the rpcbind.  Check cache first */
        addr_to_delete.len = 0;
        (void) rw_rdlock(&rpcbaddr_cache_lock);
        ad_cache = check_cache(host, nconf->nc_netid);
        if (ad_cache != NULL) {
                addr = ad_cache->ac_taddr;
                client = _clnt_tli_create_timed(RPC_ANYFD, nconf, addr,
                    RPCBPROG, RPCBVERS4, 0, 0, tp);
                if (client != NULL) {
                        if (targaddr) {
                                /*
                                 * case where a client handle is created
                                 * without a targaddr and the handle is
                                 * requested with a targaddr
                                 */
                                if (ad_cache->ac_uaddr != NULL) {
                                        *targaddr = strdup(ad_cache->ac_uaddr);
                                        if (*targaddr == NULL) {
                                                syslog(LOG_ERR,
                                                "_getclnthandle_timed: strdup "
                                                "failed.");
                                                rpc_createerr.cf_stat =
                                                    RPC_SYSTEMERROR;
                                                (void) rw_unlock(
                                                    &rpcbaddr_cache_lock);
                                                return (NULL);
                                        }
                                } else {
                                        *targaddr = NULL;
                                }
                        }
                        (void) rw_unlock(&rpcbaddr_cache_lock);
                        return (client);
                }
                if (rpc_createerr.cf_stat == RPC_SYSTEMERROR) {
                        (void) rw_unlock(&rpcbaddr_cache_lock);
                        return (NULL);
                }
                addr_to_delete.len = addr->len;
                addr_to_delete.buf = malloc(addr->len);
                if (addr_to_delete.buf == NULL) {
                        addr_to_delete.len = 0;
                } else {
                        (void) memcpy(addr_to_delete.buf, addr->buf, addr->len);
                }
        }
        (void) rw_unlock(&rpcbaddr_cache_lock);
        if (addr_to_delete.len != 0) {
                /*
                 * Assume this may be due to cache data being
                 *  outdated
                 */
                (void) rw_wrlock(&rpcbaddr_cache_lock);
                delete_cache(&addr_to_delete);
                (void) rw_unlock(&rpcbaddr_cache_lock);
                free(addr_to_delete.buf);
        }
        rpcbind_hs.h_host = host;
        rpcbind_hs.h_serv = "rpcbind";

        if ((neterr = netdir_getbyname(nconf, &rpcbind_hs, &nas)) != 0) {
                if (neterr == ND_NOHOST)
                        rpc_createerr.cf_stat = RPC_UNKNOWNHOST;
                else
                        rpc_createerr.cf_stat = RPC_N2AXLATEFAILURE;
                return (NULL);
        }
        /* XXX nas should perhaps be cached for better performance */

        for (j = 0; j < nas->n_cnt; j++) {
                addr = &(nas->n_addrs[j]);
        client = _clnt_tli_create_timed(RPC_ANYFD, nconf, addr, RPCBPROG,
            RPCBVERS4, 0, 0, tp);
        if (client)
                break;
        }

        if (client) {
                tmpaddr = targaddr ? taddr2uaddr(nconf, addr) : NULL;
                add_cache(host, nconf->nc_netid, addr, tmpaddr);
                if (targaddr) {
                        *targaddr = tmpaddr;
                }
        }
        netdir_free((char *)nas, ND_ADDRLIST);
        return (client);
}

/*
 * This routine will return a client handle that is connected to the local
 * rpcbind. Returns NULL on error.
 */
static CLIENT *
local_rpcb(void)
{
        static struct netconfig *loopnconf;
        extern mutex_t loopnconf_lock;

/* VARIABLES PROTECTED BY loopnconf_lock: loopnconf */
        (void) mutex_lock(&loopnconf_lock);
        if (loopnconf == NULL) {
                struct netconfig *nconf, *tmpnconf = NULL;
                void *nc_handle;

                nc_handle = setnetconfig();
                if (nc_handle == NULL) {
                        /* fails to open netconfig file */
                        rpc_createerr.cf_stat = RPC_UNKNOWNPROTO;
                        (void) mutex_unlock(&loopnconf_lock);
                        return (NULL);
                }
                while (nconf = getnetconfig(nc_handle)) {
                        if (strcmp(nconf->nc_protofmly, NC_LOOPBACK) == 0) {
                                tmpnconf = nconf;
                                if (nconf->nc_semantics == NC_TPI_CLTS)
                                        break;
                        }
                }
                if (tmpnconf == NULL) {
                        rpc_createerr.cf_stat = RPC_UNKNOWNPROTO;
                        (void) mutex_unlock(&loopnconf_lock);
                        return (NULL);
                }
                loopnconf = getnetconfigent(tmpnconf->nc_netid);
                /* loopnconf is never freed */
                (void) endnetconfig(nc_handle);
        }
        (void) mutex_unlock(&loopnconf_lock);
        return (getclnthandle(HOST_SELF_CONNECT, loopnconf, NULL));
}

/*
 * Set a mapping between program, version and address.
 * Calls the rpcbind service to do the mapping.
 */
bool_t
rpcb_set(const rpcprog_t program, const rpcvers_t version,
                const struct netconfig *nconf, const struct netbuf *address)
{
        CLIENT *client;
        bool_t rslt = FALSE;
        RPCB parms;
        char uidbuf[32];

        /* parameter checking */
        if (nconf == NULL) {
                rpc_createerr.cf_stat = RPC_UNKNOWNPROTO;
                return (FALSE);
        }
        if (address == NULL) {
                rpc_createerr.cf_stat = RPC_UNKNOWNADDR;
                return (FALSE);
        }
        client = local_rpcb();
        if (!client)
                return (FALSE);

        parms.r_addr = taddr2uaddr((struct netconfig *)nconf,
            (struct netbuf *)address); /* convert to universal */
        if (!parms.r_addr) {
                rpc_createerr.cf_stat = RPC_N2AXLATEFAILURE;
                return (FALSE); /* no universal address */
        }
        parms.r_prog = program;
        parms.r_vers = version;
        parms.r_netid = nconf->nc_netid;
        /*
         * Though uid is not being used directly, we still send it for
         * completeness.  For non-unix platforms, perhaps some other
         * string or an empty string can be sent.
         */
        (void) sprintf(uidbuf, "%d", (int)geteuid());
        parms.r_owner = uidbuf;

        CLNT_CALL(client, RPCBPROC_SET, (xdrproc_t)xdr_rpcb, (char *)&parms,
            (xdrproc_t)xdr_bool, (char *)&rslt, tottimeout);

        CLNT_DESTROY(client);
        free(parms.r_addr);
        return (rslt);
}

/*
 * Remove the mapping between program, version and netbuf address.
 * Calls the rpcbind service to do the un-mapping.
 * If netbuf is NULL, unset for all the transports, otherwise unset
 * only for the given transport.
 */
bool_t
rpcb_unset(const rpcprog_t program, const rpcvers_t version,
                                                const struct netconfig *nconf)
{
        CLIENT *client;
        bool_t rslt = FALSE;
        RPCB parms;
        char uidbuf[32];

        client = local_rpcb();
        if (!client)
                return (FALSE);

        parms.r_prog = program;
        parms.r_vers = version;
        if (nconf)
                parms.r_netid = nconf->nc_netid;
        else
                parms.r_netid = (char *)&nullstring[0]; /* unsets  all */
        parms.r_addr = (char *)&nullstring[0];
        (void) sprintf(uidbuf, "%d", (int)geteuid());
        parms.r_owner = uidbuf;

        CLNT_CALL(client, RPCBPROC_UNSET, (xdrproc_t)xdr_rpcb, (char *)&parms,
            (xdrproc_t)xdr_bool, (char *)&rslt, tottimeout);

        CLNT_DESTROY(client);
        return (rslt);
}

/*
 * From the merged list, find the appropriate entry
 */
static struct netbuf *
got_entry(rpcb_entry_list_ptr relp, struct netconfig *nconf)
{
        struct netbuf *na = NULL;
        rpcb_entry_list_ptr sp;
        rpcb_entry *rmap;

        for (sp = relp; sp != NULL; sp = sp->rpcb_entry_next) {
                rmap = &sp->rpcb_entry_map;
                if ((strcmp(nconf->nc_proto, rmap->r_nc_proto) == 0) &&
                    (strcmp(nconf->nc_protofmly, rmap->r_nc_protofmly) == 0) &&
                    (nconf->nc_semantics == rmap->r_nc_semantics) &&
                    (rmap->r_maddr != NULL) && (rmap->r_maddr[0] != 0)) {
                        na = uaddr2taddr(nconf, rmap->r_maddr);
                        break;
                }
        }
        return (na);
}

/*
 * Quick check to see if rpcbind is up.  Tries to connect over
 * local transport.
 */
bool_t
__rpcbind_is_up(void)
{
        struct netbuf *addr;
        int fd;
        struct t_call *sndcall;
        struct netconfig *netconf;
        bool_t res;

        if ((fd = t_open("/dev/ticotsord", O_RDWR, NULL)) == -1)
                return (TRUE);

        if (t_bind(fd, NULL, NULL) == -1) {
                (void) t_close(fd);
                return (TRUE);
        }

        /* LINTED pointer cast */
        if ((sndcall = (struct t_call *)t_alloc(fd, T_CALL, 0)) == NULL) {
                (void) t_close(fd);
                return (TRUE);
        }

        if ((netconf = getnetconfigent("ticotsord")) == NULL) {
                (void) t_free((char *)sndcall, T_CALL);
                (void) t_close(fd);
                return (FALSE);
        }
        addr = uaddr2taddr(netconf, "localhost.rpc");
        freenetconfigent(netconf);
        if (addr == NULL || addr->buf == NULL) {
                if (addr)
                        free(addr);
                (void) t_free((char *)sndcall, T_CALL);
                (void) t_close(fd);
                return (FALSE);
        }
        sndcall->addr.maxlen = addr->maxlen;
        sndcall->addr.len = addr->len;
        sndcall->addr.buf = addr->buf;

        if (t_connect(fd, sndcall, NULL) == -1)
                res = FALSE;
        else
                res = TRUE;

        sndcall->addr.maxlen = sndcall->addr.len = 0;
        sndcall->addr.buf = NULL;
        (void) t_free((char *)sndcall, T_CALL);
        free(addr->buf);
        free(addr);
        (void) t_close(fd);

        return (res);
}


/*
 * An internal function which optimizes rpcb_getaddr function.  It returns
 * the universal address of the remote service or NULL.  It also optionally
 * returns the client handle that it uses to contact the remote rpcbind.
 * The caller will re-purpose the client handle to contact the remote service.
 *
 * The algorithm used: First try version 4.  Then try version 3 (svr4).
 * Finally, if the transport is TCP or UDP, try version 2 (portmap).
 * Version 4 is now available with all current systems on the network.
 * With this algorithm, we get performance as well as a plan for
 * obsoleting version 2.
 *
 * XXX: Due to some problems with t_connect(), we do not reuse the same client
 * handle for COTS cases and hence in these cases we do not return the
 * client handle.  This code will change if t_connect() ever
 * starts working properly.  Also look under clnt_vc.c.
 */
struct netbuf *
__rpcb_findaddr_timed(rpcprog_t program, rpcvers_t version,
        struct netconfig *nconf, char *host, CLIENT **clpp, struct timeval *tp)
{
        static bool_t check_rpcbind = TRUE;
        CLIENT *client = NULL;
        RPCB parms;
        enum clnt_stat clnt_st;
        char *ua = NULL;
        uint_t vers;
        struct netbuf *address = NULL;
        void *handle;
        rpcb_entry_list_ptr relp = NULL;
        bool_t tmp_client = FALSE;

        /* parameter checking */
        if (nconf == NULL) {
                rpc_createerr.cf_stat = RPC_UNKNOWNPROTO;
                /*
                 * Setting rpc_createerr.cf_stat is sufficient.
                 * No details in rpc_createerr.cf_error needed.
                 */
                return (NULL);
        }

        parms.r_addr = NULL;

        /*
         * Use default total timeout if no timeout is specified.
         */
        if (tp == NULL)
                tp = &tottimeout;

        /*
         * Check if rpcbind is up.  This prevents needless delays when
         * accessing applications such as the keyserver while booting
         * disklessly.
         */
        if (check_rpcbind && strcmp(nconf->nc_protofmly, NC_LOOPBACK) == 0) {
                if (!__rpcbind_is_up()) {
                        rpc_createerr.cf_stat = RPC_PMAPFAILURE;
                        rpc_createerr.cf_error.re_errno = 0;
                        rpc_createerr.cf_error.re_terrno = 0;
                        goto error;
                }
                check_rpcbind = FALSE;
        }

        /*
         * First try version 4.
         */
        parms.r_prog = program;
        parms.r_vers = version;
        parms.r_owner = (char *)&nullstring[0]; /* not needed; */
        /* just for xdring */
        parms.r_netid = nconf->nc_netid; /* not really needed */

        /*
         * If a COTS transport is being used, try getting address via CLTS
         * transport.  This works only with version 4.
         */
        if (nconf->nc_semantics == NC_TPI_COTS_ORD ||
            nconf->nc_semantics == NC_TPI_COTS) {
                tmp_client = TRUE;
                if ((handle = __rpc_setconf("datagram_v")) != NULL) {
                        struct netconfig *nconf_clts;

                        while ((nconf_clts = __rpc_getconf(handle)) != NULL) {
                                if (strcmp(nconf_clts->nc_protofmly,
                                    nconf->nc_protofmly) != 0) {
                                        continue;
                                }
                                /*
                                 * Sets rpc_createerr.cf_error members
                                 * on failure
                                 */
                                client = _getclnthandle_timed(host, nconf_clts,
                                    &parms.r_addr, tp);
                                break;
                        }
                        __rpc_endconf(handle);
                }
        } else {
                /* Sets rpc_createerr.cf_error members on failure */
                client = _getclnthandle_timed(host, nconf, &parms.r_addr, tp);
        }

        if (client != NULL) {

                /* Set rpcbind version 4 */
                vers = RPCBVERS4;
                CLNT_CONTROL(client, CLSET_VERS, (char *)&vers);

                /*
                 * We also send the remote system the address we used to
                 * contact it in case it can help it connect back with us
                 */
                if (parms.r_addr == NULL) {
                        parms.r_addr = strdup(""); /* for XDRing */
                        if (parms.r_addr == NULL) {
                                syslog(LOG_ERR, "__rpcb_findaddr_timed: "
                                    "strdup failed.");
                                /* Construct a system error */
                                rpc_createerr.cf_error.re_errno = errno;
                                rpc_createerr.cf_error.re_terrno = 0;
                                rpc_createerr.cf_stat = RPC_SYSTEMERROR;
                                goto error;
                        }
                }

                CLNT_CONTROL(client, CLSET_RETRY_TIMEOUT,
                    (char *)&rpcbrmttime);

                /* Sets error structure members in client handle */
                clnt_st = CLNT_CALL(client, RPCBPROC_GETADDRLIST,
                    (xdrproc_t)xdr_rpcb, (char *)&parms,
                    (xdrproc_t)xdr_rpcb_entry_list_ptr, (char *)&relp, *tp);

                switch (clnt_st) {
                case RPC_SUCCESS: /* Call succeeded */
                        address = got_entry(relp, nconf);
                        xdr_free((xdrproc_t)xdr_rpcb_entry_list_ptr,
                            (char *)&relp);
                        if (address != NULL) {
                                /* Program number and version number matched */
                                goto done;
                        }
                        /* Program and version not found for this transport */
                        /*
                         * XXX: should have returned with RPC_PROGUNAVAIL
                         * or perhaps RPC_PROGNOTREGISTERED error but
                         * since the remote machine might not always be able
                         * to send the address on all transports, we try the
                         * regular way with version 3, then 2
                         */
                        /* Try the next version */
                        break;
                case RPC_PROGVERSMISMATCH: /* RPC protocol mismatch */
                        clnt_geterr(client, &rpc_createerr.cf_error);
                        if (rpc_createerr.cf_error.re_vers.low > vers) {
                                rpc_createerr.cf_stat = clnt_st;
                                goto error;  /* a new version, can't handle */
                        }
                        /* Try the next version */
                        break;
                case RPC_PROCUNAVAIL: /* Procedure unavailable */
                case RPC_PROGUNAVAIL: /* Program not available */
                case RPC_TIMEDOUT: /* Call timed out */
                        /* Try the next version */
                        break;
                default:
                        clnt_geterr(client, &rpc_createerr.cf_error);
                        rpc_createerr.cf_stat = RPC_PMAPFAILURE;
                        goto error;
                        break;
                }

        } else {

                /* No client */
                tmp_client = FALSE;

        } /* End of version 4 */

        /* Destroy a temporary client */
        if (client != NULL && tmp_client) {
                CLNT_DESTROY(client);
                client = NULL;
                free(parms.r_addr);
                parms.r_addr = NULL;
        }
        tmp_client = FALSE;

        /*
         * Try version 3
         */

        /* Now the same transport is to be used to get the address */
        if (client == NULL) {
                /* Sets rpc_createerr.cf_error members on failure */
                client = _getclnthandle_timed(host, nconf, &parms.r_addr, tp);
        }
        address = NULL;
        if (client != NULL) {
                if (parms.r_addr == NULL) {
                        parms.r_addr = strdup("");      /* for XDRing */
                        if (parms.r_addr == NULL) {
                                syslog(LOG_ERR, "__rpcb_findaddr_timed: "
                                    "strdup failed.");
                                /* Construct a system error */
                                rpc_createerr.cf_error.re_errno = errno;
                                rpc_createerr.cf_error.re_terrno = 0;
                                rpc_createerr.cf_stat = RPC_SYSTEMERROR;
                                goto error;
                        }
                }

                CLNT_CONTROL(client, CLSET_RETRY_TIMEOUT,
                    (char *)&rpcbrmttime);
                vers = RPCBVERS; /* Set the version */
                CLNT_CONTROL(client, CLSET_VERS, (char *)&vers);

                /* Sets error structure members in client handle */
                clnt_st = CLNT_CALL(client, RPCBPROC_GETADDR,
                    (xdrproc_t)xdr_rpcb, (char *)&parms,
                    (xdrproc_t)xdr_wrapstring, (char *)&ua, *tp);

                switch (clnt_st) {
                case RPC_SUCCESS: /* Call succeeded */
                        if (ua != NULL) {
                                if (ua[0] != '\0') {
                                        address = uaddr2taddr(nconf, ua);
                                }
                                xdr_free((xdrproc_t)xdr_wrapstring,
                                    (char *)&ua);

                                if (address != NULL) {
                                        goto done;
                                }
                                /* NULL universal address */
                                /* But client call was successful */
                                clnt_geterr(client, &rpc_createerr.cf_error);
                                rpc_createerr.cf_stat = RPC_PROGNOTREGISTERED;
                                goto error;
                        }
#ifndef PORTMAP
                        clnt_geterr(client, &rpc_createerr.cf_error);
                        rpc_createerr.cf_stat = RPC_UNKNOWNPROTO;
                        goto error;
#endif
                        /* Try the next version */
                        break;
                case RPC_PROGVERSMISMATCH: /* RPC protocol mismatch */
                        clnt_geterr(client, &rpc_createerr.cf_error);
#ifdef PORTMAP
                        if (rpc_createerr.cf_error.re_vers.low > vers) {
                                rpc_createerr.cf_stat = clnt_st;
                                goto error;  /* a new version, can't handle */
                        }
#else
                        rpc_createerr.cf_stat = clnt_st;
                        goto error;
#endif
                        /* Try the next version */
                        break;
#ifdef PORTMAP
                case RPC_PROCUNAVAIL: /* Procedure unavailable */
                case RPC_PROGUNAVAIL: /* Program not available */
                case RPC_TIMEDOUT: /* Call timed out */
                        /* Try the next version */
                        break;
#endif
                default:
                        clnt_geterr(client, &rpc_createerr.cf_error);
                        rpc_createerr.cf_stat = RPC_PMAPFAILURE;
                        goto error;
                        break;
                }
        } /* End of version 3 */
#ifndef PORTMAP
        /* cf_error members set by creation failure */
        rpc_createerr.cf_stat = RPC_PROGNOTREGISTERED;
#endif
        /*
         * Try version 2
         */

#ifdef PORTMAP
        /* Try version 2 for TCP or UDP */
        if (strcmp(nconf->nc_protofmly, NC_INET) == 0) {
                ushort_t port = 0;
                struct netbuf remote;
                uint_t pmapvers = 2;
                struct pmap pmapparms;

                /*
                 * Try UDP only - there are some portmappers out
                 * there that use UDP only.
                 */
                if (strcmp(nconf->nc_proto, NC_TCP) == 0) {
                        struct netconfig *newnconf;

                        if (client != NULL) {
                                CLNT_DESTROY(client);
                                client = NULL;
                                free(parms.r_addr);
                                parms.r_addr = NULL;
                        }
                        if ((handle = __rpc_setconf("udp")) == NULL) {
                                /* Construct an unknown protocol error */
                                rpc_createerr.cf_stat = RPC_UNKNOWNPROTO;
                                goto error;
                        }

                        /*
                         * The following to reinforce that you can
                         * only request for remote address through
                         * the same transport you are requesting.
                         * ie. requesting unversial address
                         * of IPv4 has to be carried through IPv4.
                         * Can't use IPv6 to send out the request.
                         * The mergeaddr in rpcbind can't handle
                         * this.
                         */
                        for (;;) {
                                if ((newnconf = __rpc_getconf(handle))
                                    == NULL) {
                                        __rpc_endconf(handle);
                                        /*
                                         * Construct an unknown protocol
                                         * error
                                         */
                                        rpc_createerr.cf_stat =
                                            RPC_UNKNOWNPROTO;
                                        goto error;
                                }
                                /*
                                 * here check the protocol family to
                                 * be consistent with the request one
                                 */
                                if (strcmp(newnconf->nc_protofmly,
                                    nconf->nc_protofmly) == 0)
                                        break;
                        }

                        /* Sets rpc_createerr.cf_error members on failure */
                        client = _getclnthandle_timed(host, newnconf,
                            &parms.r_addr, tp);
                        __rpc_endconf(handle);
                        tmp_client = TRUE;
                }
                if (client == NULL) {
                        /*
                         * rpc_createerr. cf_error members were set by
                         * creation failure
                         */
                        rpc_createerr.cf_stat = RPC_PROGNOTREGISTERED;
                        tmp_client = FALSE;
                        goto error;
                }

                /*
                 * Set version and retry timeout.
                 */
                CLNT_CONTROL(client, CLSET_RETRY_TIMEOUT, (char *)&rpcbrmttime);
                CLNT_CONTROL(client, CLSET_VERS, (char *)&pmapvers);

                pmapparms.pm_prog = program;
                pmapparms.pm_vers = version;
                pmapparms.pm_prot = (strcmp(nconf->nc_proto, NC_TCP) != 0) ?
                    IPPROTO_UDP : IPPROTO_TCP;
                pmapparms.pm_port = 0;  /* not needed */

                /* Sets error structure members in client handle */
                clnt_st = CLNT_CALL(client, PMAPPROC_GETPORT,
                    (xdrproc_t)xdr_pmap, (caddr_t)&pmapparms,
                    (xdrproc_t)xdr_u_short, (caddr_t)&port, *tp);

                if (clnt_st != RPC_SUCCESS) {
                        clnt_geterr(client, &rpc_createerr.cf_error);
                        rpc_createerr.cf_stat = RPC_RPCBFAILURE;
                        goto error;
                } else if (port == 0) {
                        /* Will be NULL universal address */
                        /* But client call was successful */
                        clnt_geterr(client, &rpc_createerr.cf_error);
                        rpc_createerr.cf_stat = RPC_PROGNOTREGISTERED;
                        goto error;
                }
                port = htons(port);
                CLNT_CONTROL(client, CLGET_SVC_ADDR, (char *)&remote);
                if (((address = malloc(sizeof (struct netbuf))) == NULL) ||
                    ((address->buf = malloc(remote.len)) == NULL)) {
                        /* Construct a system error */
                        rpc_createerr.cf_error.re_errno = errno;
                        rpc_createerr.cf_error.re_terrno = 0;
                        rpc_createerr.cf_stat = RPC_SYSTEMERROR;
                        free(address);
                        address = NULL;
                        goto error;
                }
                (void) memcpy(address->buf, remote.buf, remote.len);
                (void) memcpy(&address->buf[sizeof (short)], &port,
                    sizeof (short));
                address->len = address->maxlen = remote.len;
                goto done;
        } else {
                /*
                 * This is not NC_INET.
                 * Always an error for version 2.
                 */
                if (client != NULL && clnt_st != RPC_SUCCESS) {
                        /* There is a client that failed */
                        clnt_geterr(client, &rpc_createerr.cf_error);
                        rpc_createerr.cf_stat = clnt_st;
                } else {
                        /* Something else */
                        rpc_createerr.cf_stat = RPC_UNKNOWNPROTO;
                        /*
                         * Setting rpc_createerr.cf_stat is sufficient.
                         * No details in rpc_createerr.cf_error needed.
                         */
                }
        }
#endif

error:
        /* Return NULL address and NULL client */
        address = NULL;
        if (client != NULL) {
                CLNT_DESTROY(client);
                client = NULL;
        }

done:
        /* Return an address and optional client */
        if (client != NULL && tmp_client) {
                /* This client is the temporary one */
                CLNT_DESTROY(client);
                client = NULL;
        }
        if (clpp != NULL) {
                *clpp = client;
        } else if (client != NULL) {
                CLNT_DESTROY(client);
        }
        free(parms.r_addr);
        return (address);
}


/*
 * Find the mapped address for program, version.
 * Calls the rpcbind service remotely to do the lookup.
 * Uses the transport specified in nconf.
 * Returns FALSE (0) if no map exists, else returns 1.
 *
 * Assuming that the address is all properly allocated
 */
int
rpcb_getaddr(const rpcprog_t program, const rpcvers_t version,
        const struct netconfig *nconf, struct netbuf *address, const char *host)
{
        struct netbuf *na;

        if ((na = __rpcb_findaddr_timed(program, version,
            (struct netconfig *)nconf, (char *)host, NULL, NULL)) == NULL)
                return (FALSE);

        if (na->len > address->maxlen) {
                /* Too long address */
                netdir_free((char *)na, ND_ADDR);
                rpc_createerr.cf_stat = RPC_FAILED;
                return (FALSE);
        }
        (void) memcpy(address->buf, na->buf, (int)na->len);
        address->len = na->len;
        netdir_free((char *)na, ND_ADDR);
        return (TRUE);
}

/*
 * Get a copy of the current maps.
 * Calls the rpcbind service remotely to get the maps.
 *
 * It returns only a list of the services
 * It returns NULL on failure.
 */
rpcblist *
rpcb_getmaps(const struct netconfig *nconf, const char *host)
{
        rpcblist_ptr head = NULL;
        CLIENT *client;
        enum clnt_stat clnt_st;
        int vers = 0;

        client = getclnthandle((char *)host,
            (struct netconfig *)nconf, NULL);
        if (client == NULL)
                return (NULL);

        clnt_st = CLNT_CALL(client, RPCBPROC_DUMP,
            (xdrproc_t)xdr_void, NULL,
            (xdrproc_t)xdr_rpcblist_ptr,
            (char *)&head, tottimeout);
        if (clnt_st == RPC_SUCCESS)
                goto done;

        if ((clnt_st != RPC_PROGVERSMISMATCH) &&
            (clnt_st != RPC_PROGUNAVAIL)) {
                rpc_createerr.cf_stat = RPC_RPCBFAILURE;
                clnt_geterr(client, &rpc_createerr.cf_error);
                goto done;
        }

        /* fall back to earlier version */
        CLNT_CONTROL(client, CLGET_VERS, (char *)&vers);
        if (vers == RPCBVERS4) {
                vers = RPCBVERS;
                CLNT_CONTROL(client, CLSET_VERS, (char *)&vers);
                if (CLNT_CALL(client, RPCBPROC_DUMP,
                    (xdrproc_t)xdr_void,
                    NULL, (xdrproc_t)xdr_rpcblist_ptr,
                    (char *)&head, tottimeout) == RPC_SUCCESS)
                                goto done;
        }
        rpc_createerr.cf_stat = RPC_RPCBFAILURE;
        clnt_geterr(client, &rpc_createerr.cf_error);

done:
        CLNT_DESTROY(client);
        return (head);
}

/*
 * rpcbinder remote-call-service interface.
 * This routine is used to call the rpcbind remote call service
 * which will look up a service program in the address maps, and then
 * remotely call that routine with the given parameters. This allows
 * programs to do a lookup and call in one step.
 */
enum clnt_stat
rpcb_rmtcall(const struct netconfig *nconf, const char *host,
        const rpcprog_t prog, const rpcvers_t vers, const rpcproc_t proc,
        const xdrproc_t xdrargs, const caddr_t argsp, const xdrproc_t xdrres,
        const caddr_t resp, const struct timeval tout, struct netbuf *addr_ptr)
{
        CLIENT *client;
        enum clnt_stat stat;
        struct r_rpcb_rmtcallargs a;
        struct r_rpcb_rmtcallres r;
        int rpcb_vers;

        client = getclnthandle((char *)host, (struct netconfig *)nconf, NULL);
        if (client == NULL)
                return (RPC_FAILED);
        CLNT_CONTROL(client, CLSET_RETRY_TIMEOUT, (char *)&rmttimeout);
        a.prog = prog;
        a.vers = vers;
        a.proc = proc;
        a.args.args_val = argsp;
        a.xdr_args = xdrargs;
        r.addr = NULL;
        r.results.results_val = resp;
        r.xdr_res = xdrres;

        for (rpcb_vers = RPCBVERS4; rpcb_vers >= RPCBVERS; rpcb_vers--) {
                CLNT_CONTROL(client, CLSET_VERS, (char *)&rpcb_vers);
                stat = CLNT_CALL(client, RPCBPROC_CALLIT,
                    (xdrproc_t)xdr_rpcb_rmtcallargs, (char *)&a,
                    (xdrproc_t)xdr_rpcb_rmtcallres, (char *)&r, tout);
                if ((stat == RPC_SUCCESS) && (addr_ptr != NULL)) {
                        struct netbuf *na;

                        na = uaddr2taddr((struct netconfig *)nconf, r.addr);
                        if (!na) {
                                stat = RPC_N2AXLATEFAILURE;
                                ((struct netbuf *)addr_ptr)->len = 0;
                                goto error;
                        }
                        if (na->len > addr_ptr->maxlen) {
                                /* Too long address */
                                stat = RPC_FAILED; /* XXX A better error no */
                                netdir_free((char *)na, ND_ADDR);
                                ((struct netbuf *)addr_ptr)->len = 0;
                                goto error;
                        }
                        (void) memcpy(addr_ptr->buf, na->buf, (int)na->len);
                        ((struct netbuf *)addr_ptr)->len = na->len;
                        netdir_free((char *)na, ND_ADDR);
                        break;
                }
                if ((stat != RPC_PROGVERSMISMATCH) &&
                    (stat != RPC_PROGUNAVAIL))
                        goto error;
        }
error:
        CLNT_DESTROY(client);
        if (r.addr)
                xdr_free((xdrproc_t)xdr_wrapstring, (char *)&r.addr);
        return (stat);
}

/*
 * Gets the time on the remote host.
 * Returns 1 if succeeds else 0.
 */
bool_t
rpcb_gettime(const char *host, time_t *timep)
{
        CLIENT *client = NULL;
        void *handle;
        struct netconfig *nconf;
        int vers;
        enum clnt_stat st;

        if ((host == NULL) || (host[0] == '\0')) {
                (void) time(timep);
                return (TRUE);
        }

        if ((handle = __rpc_setconf("netpath")) == NULL) {
                rpc_createerr.cf_stat = RPC_UNKNOWNPROTO;
                return (FALSE);
        }
        rpc_createerr.cf_stat = RPC_SUCCESS;
        while (client == NULL) {
                if ((nconf = __rpc_getconf(handle)) == NULL) {
                        if (rpc_createerr.cf_stat == RPC_SUCCESS)
                                rpc_createerr.cf_stat = RPC_UNKNOWNPROTO;
                        break;
                }
                client = getclnthandle((char *)host, nconf, NULL);
                if (client)
                        break;
        }
        __rpc_endconf(handle);
        if (client == NULL)
                return (FALSE);

        st = CLNT_CALL(client, RPCBPROC_GETTIME,
            (xdrproc_t)xdr_void, NULL,
            (xdrproc_t)xdr_time_t, (char *)timep, tottimeout);

        if ((st == RPC_PROGVERSMISMATCH) || (st == RPC_PROGUNAVAIL)) {
                CLNT_CONTROL(client, CLGET_VERS, (char *)&vers);
                if (vers == RPCBVERS4) {
                        /* fall back to earlier version */
                        vers = RPCBVERS;
                        CLNT_CONTROL(client, CLSET_VERS, (char *)&vers);
                        st = CLNT_CALL(client, RPCBPROC_GETTIME,
                            (xdrproc_t)xdr_void, NULL,
                            (xdrproc_t)xdr_time_t, (char *)timep,
                            tottimeout);
                }
        }
        CLNT_DESTROY(client);
        return (st == RPC_SUCCESS? TRUE : FALSE);
}

/*
 * Converts taddr to universal address.  This routine should never
 * really be called because local n2a libraries are always provided.
 */
char *
rpcb_taddr2uaddr(struct netconfig *nconf, struct netbuf *taddr)
{
        CLIENT *client;
        char *uaddr = NULL;

        /* parameter checking */
        if (nconf == NULL) {
                rpc_createerr.cf_stat = RPC_UNKNOWNPROTO;
                return (NULL);
        }
        if (taddr == NULL) {
                rpc_createerr.cf_stat = RPC_UNKNOWNADDR;
                return (NULL);
        }
        client = local_rpcb();
        if (!client)
                return (NULL);

        CLNT_CALL(client, RPCBPROC_TADDR2UADDR, (xdrproc_t)xdr_netbuf,
            (char *)taddr, (xdrproc_t)xdr_wrapstring, (char *)&uaddr,
            tottimeout);
        CLNT_DESTROY(client);
        return (uaddr);
}

/*
 * Converts universal address to netbuf.  This routine should never
 * really be called because local n2a libraries are always provided.
 */
struct netbuf *
rpcb_uaddr2taddr(struct netconfig *nconf, char *uaddr)
{
        CLIENT *client;
        struct netbuf *taddr;

        /* parameter checking */
        if (nconf == NULL) {
                rpc_createerr.cf_stat = RPC_UNKNOWNPROTO;
                return (NULL);
        }
        if (uaddr == NULL) {
                rpc_createerr.cf_stat = RPC_UNKNOWNADDR;
                return (NULL);
        }
        client = local_rpcb();
        if (!client)
                return (NULL);

        taddr = calloc(1, sizeof (struct netbuf));
        if (taddr == NULL) {
                CLNT_DESTROY(client);
                return (NULL);
        }

        if (CLNT_CALL(client, RPCBPROC_UADDR2TADDR, (xdrproc_t)xdr_wrapstring,
            (char *)&uaddr, (xdrproc_t)xdr_netbuf, (char *)taddr,
            tottimeout) != RPC_SUCCESS) {
                free(taddr);
                taddr = NULL;
        }
        CLNT_DESTROY(client);
        return (taddr);
}