/*
 * 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 2003 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 * Copyright (c) 2016 by Delphix. All rights reserved.
 */

/*      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.
 */

/*
 *
 * This contains YP server code which supplies the set of functions
 * requested using rpc.   The top level functions in this module
 * are those which have symbols of the form YPPROC_xxxx defined in
 * yp_prot.h, and symbols of the form YPOLDPROC_xxxx defined in ypsym.h.
 * The latter exist to provide compatibility to the old version of the yp
 * protocol/server, and may emulate the behavior of the previous software
 * by invoking some other program.
 *
 * This module also contains functions which are used by (and only by) the
 * top-level functions here.
 */

#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <dirent.h>
#include <limits.h>
#include <sys/systeminfo.h>
#include <rpc/rpc.h>
#include <string.h>
#include <malloc.h>
#include <stdlib.h>
#include <unistd.h>
#include <stdio.h>
#include "ypsym.h"
#include "ypdefs.h"
#include <ctype.h>

/* Use shim version of DBM calls */
#include "shim.h"
#include "shim_hooks.h"

USE_YP_PREFIX
USE_YP_SECURE
USE_YP_INTERDOMAIN

#ifndef YPXFR_PROC
#define YPXFR_PROC "/usr/lib/netsvc/yp/ypxfr"
#endif
static char ypxfr_proc[] = YPXFR_PROC;
#ifndef YPPUSH_PROC
#define YPPUSH_PROC "/usr/lib/netsvc/yp/yppush"
#endif
static char yppush_proc[] = YPPUSH_PROC;
struct yppriv_sym {
    char *sym;
    unsigned len;
};
static  char err_fork[] = "ypserv:  %s fork failure.\n";
#define FORK_ERR logprintf(err_fork, fun)
static char err_execl[] = "ypserv:  %s execl failure.\n";
#define EXEC_ERR logprintf(err_execl, fun)
static char err_respond[] = "ypserv: %s can't respond to rpc request.\n";
#define RESPOND_ERR logprintf(err_respond, fun)
static char err_free[] = "ypserv: %s can't free args.\n";
#define FREE_ERR logprintf(err_free, fun)
static char err_map[] = "ypserv: %s no such map or access denied.\n";
#define MAP_ERR logprintf(err_map, fun)
static char err_vers[] = "ypserv: %s version not supported.\n";
#define VERS_ERR logprintf(err_vers, fun)

static void ypfilter(DBM *fdb, datum *inkey, datum *outkey, datum *val,
                        uint_t *status, bool_t update);
static bool isypsym(datum *key);
static bool xdrypserv_ypall(XDR *xdrs, struct ypreq_nokey *req);
static int multihomed(struct ypreq_key req, struct ypresp_val *resp,
                        SVCXPRT *xprt, DBM *fdb);
static int omultihomed(struct yprequest req, struct ypresponse *resp,
                        SVCXPRT *xprt, DBM *fdb);


/* For DNS forwarding */
extern bool dnsforward;
extern bool client_setup_failure;
extern int resolv_pid;
extern CLIENT *resolv_client;
extern char *resolv_tp;

/*
 * This determines whether or not a passed domain is served by this
 * server, and returns a boolean.  Used by both old and new protocol
 * versions.
 */
void
ypdomain(SVCXPRT *transp, bool always_respond)
{
        char domain_name[YPMAXDOMAIN + 1];
        char *pdomain_name = domain_name;
        bool isserved;
        char *fun = "ypdomain";
        struct netbuf *nbuf;
        sa_family_t af;

        memset(domain_name, 0, sizeof (domain_name));

        if (!svc_getargs(transp, (xdrproc_t)xdr_ypdomain_wrap_string,
                                (caddr_t)&pdomain_name)) {
                svcerr_decode(transp);
                return;
        }

        /*
         * If the file /var/yp/securenets is present on the server, and if
         * the hostname is present in the file, then let the client bind to
         * the server.
         */
        nbuf = svc_getrpccaller(transp);
        af = ((struct sockaddr_storage *)nbuf->buf)->ss_family;
        if (af != AF_INET && af != AF_INET6) {
                logprintf("Protocol incorrect\n");
                return;
        }

        if (!(check_secure_net_ti(nbuf, fun))) {
                MAP_ERR;
                return;
        }

        isserved = ypcheck_domain(domain_name);

        if (isserved || always_respond) {

                if (!svc_sendreply(transp, xdr_bool, (char *)&isserved)) {
                    RESPOND_ERR;
                }
                if (!isserved)
                        logprintf("Domain %s not supported\n",
                                        domain_name);

        } else {
                /*
                 * This case is the one in which the domain is not
                 * supported, and in which we are not to respond in the
                 * unsupported case.  We are going to make an error happen
                 * to allow the portmapper to end its wait without the
                 * normal timeout period.  The assumption here is that
                 * the only process in the world which is using the function
                 * in its no-answer-if-nack form is the portmapper, which is
                 * doing the krock for pseudo-broadcast.  If some poor fool
                 * calls this function as a single-cast message, the nack
                 * case will look like an incomprehensible error.  Sigh...
                 * (The traditional Unix disclaimer)
                 */

                svcerr_decode(transp);
                logprintf("Domain %s not supported (broadcast)\n",
                                domain_name);
        }
}

/*
 * This implements the yp "match" function.
 */
void
ypmatch(SVCXPRT *transp, struct svc_req *rqstp)
{
        struct ypreq_key req;
        struct ypresp_val resp;
        char *fun = "ypmatch";
        DBM *fdb;

        memset(&req, 0, sizeof (req));
        memset(&resp, 0, sizeof (resp));
        resp.status = (unsigned)YP_NOKEY;

        if (!svc_getargs(transp, (xdrproc_t)xdr_ypreq_key, (char *)&req)) {
                svcerr_decode(transp);
                return;
        }

        /*
         * sanity check the map name and to a DBM lookup
         * also perform an access check...
         */
        if ((fdb = ypset_current_map(req.map, req.domain,
                                        &resp.status)) != NULL &&
                yp_map_access(transp, &resp.status, fdb)) {

                /* Check with the DBM database */
                resp.valdat = dbm_fetch(fdb, req.keydat);
                if (resp.valdat.dptr != NULL) {
                        resp.status = YP_TRUE;
                        if (!silent)
                                printf("%s: dbm: %40.40s\n",
                                        fun, resp.valdat.dptr);
                        goto send_reply;
                }

                /*
                 * If we're being asked to match YP_SECURE or YP_INTERDOMAIN
                 * and we haven't found it in the dbm file, then we don't
                 * really want to waste any more time.  Specifically, we don't
                 * want to ask DNS
                 */
                if (req.keydat.dsize == 0 ||
                    req.keydat.dptr == NULL ||
                    req.keydat.dptr[0] == '\0' ||
        strncmp(req.keydat.dptr, yp_secure, req.keydat.dsize) == 0 ||
        strncmp(req.keydat.dptr, yp_interdomain, req.keydat.dsize) == 0) {
                        goto send_reply;
                }

                /* Let's try the YP_MULTI_ hack... */
#ifdef MINUS_C_OPTION
                if (multiflag == TRUE && multihomed(req, &resp, transp, fdb))
                        goto send_reply;
#else
                if (multihomed(req, &resp, transp, fdb))
                        goto send_reply;
#endif

                /*
                 * Let's try DNS, but if client_setup_failure is set,
                 * we have tried DNS in the past and failed, there is
                 * no reason in forcing an infinite loop by turning
                 * off DNS in setup_resolv() only to turn it back on
                 * again here.
                 */
                if (!dnsforward && !client_setup_failure) {
                        datum idkey, idval;
                        idkey.dptr = yp_interdomain;
                        idkey.dsize = yp_interdomain_sz;
                        idval = dbm_fetch(fdb, idkey);
                        if (idval.dptr)
                                dnsforward = TRUE;
                }

                if (dnsforward) {
                        if (!resolv_pid || !resolv_client) {
                                setup_resolv(&dnsforward, &resolv_pid,
                                                &resolv_client, resolv_tp, 0);
                                if (resolv_client == NULL)
                                        client_setup_failure = TRUE;
                        }

                        if (resolv_req(&dnsforward, &resolv_client,
                                                &resolv_pid, resolv_tp,
                                                rqstp->rq_xprt, &req,
                                                req.map) == TRUE)
                                goto free_args;
                }
        }
        send_reply:

        if (!svc_sendreply(transp, (xdrproc_t)xdr_ypresp_val,
                                (caddr_t)&resp)) {
                RESPOND_ERR;
        }

        free_args:

        if (!svc_freeargs(transp, (xdrproc_t)xdr_ypreq_key,
                                (char *)&req)) {
                FREE_ERR;
        }
}


/*
 * This implements the yp "get first" function.
 */
void
ypfirst(SVCXPRT *transp)
{
        struct ypreq_nokey req;
        struct ypresp_key_val resp;
        char *fun = "ypfirst";
        DBM *fdb;

        memset(&req, 0, sizeof (req));
        memset(&resp, 0, sizeof (resp));

        if (!svc_getargs(transp,
                                (xdrproc_t)xdr_ypreq_nokey,
                                (char *)&req)) {
                svcerr_decode(transp);
                return;
        }

        if ((fdb = ypset_current_map(req.map, req.domain,
                                        &resp.status)) != NULL &&
                yp_map_access(transp, &resp.status, fdb)) {
                ypfilter(fdb, NULL,
                        &resp.keydat, &resp.valdat, &resp.status, FALSE);
        }

        if (!svc_sendreply(transp,
                                (xdrproc_t)xdr_ypresp_key_val,
                                (char *)&resp)) {
                RESPOND_ERR;
        }

        if (!svc_freeargs(transp, (xdrproc_t)xdr_ypreq_nokey,
                                (char *)&req)) {
                FREE_ERR;
        }
}

/*
 * This implements the yp "get next" function.
 */
void
ypnext(SVCXPRT *transp)
{
        struct ypreq_key req;
        struct ypresp_key_val resp;
        char *fun = "ypnext";
        DBM *fdb;

        memset(&req, 0, sizeof (req));
        memset(&resp, 0, sizeof (resp));

        if (!svc_getargs(transp, (xdrproc_t)xdr_ypreq_key, (char *)&req)) {
                svcerr_decode(transp);
                return;
        }

        if ((fdb = ypset_current_map(req.map, req.domain,
                                        &resp.status)) != NULL &&
                yp_map_access(transp, &resp.status, fdb)) {
                ypfilter(fdb, &req.keydat,
                        &resp.keydat, &resp.valdat, &resp.status, FALSE);
        }

        if (!svc_sendreply(transp,
                                (xdrproc_t)xdr_ypresp_key_val,
                                (char *)&resp)) {
                RESPOND_ERR;
        }

        if (!svc_freeargs(transp,
                                (xdrproc_t)xdr_ypreq_key,
                                (char *)&req)) {
                FREE_ERR;
        }
}

/*
 * This implements the "transfer map" function.  It takes the domain
 * and map names and the callback information provided by the
 * requester (yppush on some node), and execs a ypxfr process to do
 * the actual transfer.
 */
void
ypxfr(SVCXPRT *transp, int prog)
{
        struct ypreq_newxfr newreq;
        struct ypreq_xfr oldreq;
        struct ypresp_val resp;  /* not returned to the caller */
        char transid[32];
        char proto[32];
        char name[256];
        char *pdomain, *pmap;
        pid_t pid = -1;
        char *fun = "ypxfr";
        DBM *fdb;

        if (prog == YPPROC_NEWXFR) {
                memset(&newreq, 0, sizeof (newreq));
                if (!svc_getargs(transp, (xdrproc_t)xdr_ypreq_newxfr,
                                (char *)&newreq)) {
                        svcerr_decode(transp);
                        return;
                }

#ifdef OPCOM_DEBUG
                fprintf(stderr, "newreq:\n"
                        "\tmap_parms:\n"
                        "\t\tdomain:    %s\n"
                        "\t\tmap:       %s\n"
                        "\t\tordernum:  %u\n"
                        "\t\towner:     %s\n"
                        "\ttransid:    %u\n"
                        "\tproto:      %u\n"
                        "\tname:       %s\n\n",
                        newreq.map_parms.domain,
                        newreq.map_parms.map,
                        newreq.map_parms.ordernum,
                        newreq.map_parms.owner,
                        newreq.transid,
                        newreq.proto,
                        newreq.name);
#endif
                sprintf(transid, "%u", newreq.transid);
                sprintf(proto, "%u", newreq.proto);
                sprintf(name, "%s", newreq.ypxfr_owner);
                pdomain = newreq.ypxfr_domain;
                pmap = newreq.ypxfr_map;
        } else if (prog == YPPROC_XFR) {
                memset(&oldreq, 0, sizeof (oldreq));
                if (!svc_getargs(transp,
                                        (xdrproc_t)xdr_ypreq_xfr,
                                        (char *)&oldreq)) {
                    svcerr_decode(transp);
                    return;
                }

#ifdef OPCOM_DEBUG
                fprintf(stderr, "oldreq:\n"
                        "\tmap_parms:\n"
                        "\t\tdomain:    %s\n"
                        "\t\tmap:       %s\n"
                        "\t\tordernum:  %u\n"
                        "\t\towner:     %s\n"
                        "\ttransid:    %u\n"
                        "\tproto:      %u\n"
                        "\tport:       %u\n\n",
                        oldreq.map_parms.domain,
                        oldreq.map_parms.map,
                        oldreq.map_parms.ordernum,
                        oldreq.map_parms.owner,
                        oldreq.transid,
                        oldreq.proto,
                        oldreq.port);
#endif

                sprintf(transid, "%u", oldreq.transid);
                sprintf(proto, "%u", oldreq.proto);
                sprintf(name, "%s", oldreq.ypxfr_owner);
                pdomain = oldreq.ypxfr_domain;
                pmap = oldreq.ypxfr_map;
        } else {
                VERS_ERR;
        }

        /* Check that the map exists and is accessible */
        if ((fdb = ypset_current_map(pmap, pdomain, &resp.status)) != NULL &&
                yp_map_access(transp, &resp.status, fdb)) {

                pid = vfork();
                if (pid == -1) {
                        FORK_ERR;
                } else if (pid == 0) {
                    if (prog == YPPROC_NEWXFR || prog == YPPROC_XFR) {
#ifdef OPCOM_DEBUG
                        fprintf(stderr,
                                "EXECL: %s, -d, %s, -C, %s, %s, %s, %s\n",
                                ypxfr_proc, pdomain,
                                transid, proto, name, pmap);
#endif
                        if (execl(ypxfr_proc, "ypxfr", "-d",
                                        pdomain, "-C", transid, proto,
                                        name, pmap, NULL))
                            EXEC_ERR;
                    } else {
                        VERS_ERR;
                    }
                    _exit(1);
                }

        } else {
                MAP_ERR;
        }
        if (!svc_sendreply(transp, xdr_void, 0)) {
                RESPOND_ERR;
        }

        if (prog == YPPROC_NEWXFR) {
                if (!svc_freeargs(transp,
                                        (xdrproc_t)xdr_ypreq_newxfr,
                                        (char *)&newreq)) {
                    FREE_ERR;
                }
        }
}

/*
 * This implements the "get all" function.
 */
void
ypall(SVCXPRT *transp)
{
        struct ypreq_nokey req;
        struct ypresp_val resp;  /* not returned to the caller */
        pid_t pid;
        char *fun = "ypall";
        DBM *fdb;

        req.domain = req.map = NULL;

        memset((char *)&req, 0, sizeof (req));

        if (!svc_getargs(transp,
                                (xdrproc_t)xdr_ypreq_nokey,
                                (char *)&req)) {
                svcerr_decode(transp);
                return;
        }

        pid = fork1();

        if (pid) {

                if (pid == -1) {
                        FORK_ERR;
                }

                if (!svc_freeargs(transp,
                                        (xdrproc_t)xdr_ypreq_nokey,
                                        (char *)&req)) {
                        FREE_ERR;
                }

                return;
        }

        /*
         * access control hack:  If denied then invalidate the map name.
         */
        ypclr_current_map();
        if ((fdb = ypset_current_map(req.map,
                req.domain, &resp.status)) != NULL &&
                !yp_map_access(transp, &resp.status, fdb)) {

                req.map[0] = '-';
        }

        /*
         * This is the child process.  The work gets done by xdrypserv_ypall/
         * we must clear the "current map" first so that we do not
         * share a seek pointer with the parent server.
         */

        if (!svc_sendreply(transp,
                                (xdrproc_t)xdrypserv_ypall,
                                (char *)&req)) {
                RESPOND_ERR;
        }

        if (!svc_freeargs(transp,
                                (xdrproc_t)xdr_ypreq_nokey,
                                (char *)&req)) {
                FREE_ERR;
        }

        /*
         * In yptol mode we may start a cache update thread within a child
         * process. It is thus important that child processes do not exit,
         * killing any such threads, before the thread has completed.
         */
        if (yptol_mode) {
                thr_join(0, NULL, NULL);
        }

        exit(0);
}

/*
 * This implements the "get master name" function.
 */
void
ypmaster(SVCXPRT *transp)
{
        struct ypreq_nokey req;
        struct ypresp_master resp;
        char *nullstring = "";
        char *fun = "ypmaster";
        DBM *fdb;

        memset((char *)&req, 0, sizeof (req));
        resp.master = nullstring;
        resp.status = YP_TRUE;

        if (!svc_getargs(transp,
                                (xdrproc_t)xdr_ypreq_nokey,
                                (char *)&req)) {
                svcerr_decode(transp);
                return;
        }

        if ((fdb = ypset_current_map(req.map,
                req.domain, &resp.status)) != NULL &&
                yp_map_access(transp, &resp.status, fdb)) {

                if (!ypget_map_master(&resp.master, fdb)) {
                        resp.status = (unsigned)YP_BADDB;
                }
        }

        if (!svc_sendreply(transp,
                                (xdrproc_t)xdr_ypresp_master,
                                (char *)&resp)) {
                RESPOND_ERR;
        }

        if (!svc_freeargs(transp,
                                (xdrproc_t)xdr_ypreq_nokey,
                                (char *)&req)) {
                FREE_ERR;
        }
}

/*
 * This implements the "get order number" function.
 */
void
yporder(SVCXPRT *transp)
{
        struct ypreq_nokey req;
        struct ypresp_order resp;
        char *fun = "yporder";
        DBM *fdb;

        req.domain = req.map = NULL;
        resp.status  = YP_TRUE;
        resp.ordernum  = 0;

        memset((char *)&req, 0, sizeof (req));

        if (!svc_getargs(transp,
                                (xdrproc_t)xdr_ypreq_nokey,
                                (char *)&req)) {
                svcerr_decode(transp);
                return;
        }

        resp.ordernum = 0;

        if ((fdb = ypset_current_map(req.map,
                                        req.domain,
                                        &resp.status)) != NULL &&
                yp_map_access(transp, &resp.status, fdb)) {

                if (!ypget_map_order(req.map, req.domain, &resp.ordernum)) {
                        resp.status = (unsigned)YP_BADDB;
                }
        }

        if (!svc_sendreply(transp,
                                (xdrproc_t)xdr_ypresp_order,
                                (char *)&resp)) {
                RESPOND_ERR;
        }

        if (!svc_freeargs(transp,
                                (xdrproc_t)xdr_ypreq_nokey,
                                (char *)&req)) {
                FREE_ERR;
        }
}

void
ypmaplist(SVCXPRT *transp)
{
        char domain_name[YPMAXDOMAIN + 1];
        char *pdomain = domain_name;
        char *fun = "ypmaplist";
        struct ypresp_maplist maplist;
        struct ypmaplist *tmp;

        maplist.list = (struct ypmaplist *)NULL;

        memset(domain_name, 0, sizeof (domain_name));

        if (!svc_getargs(transp,
                                (xdrproc_t)xdr_ypdomain_wrap_string,
                                (caddr_t)&pdomain)) {
                svcerr_decode(transp);
                return;
        }

        maplist.status = yplist_maps(domain_name, &maplist.list);

        if (!svc_sendreply(transp,
                                (xdrproc_t)xdr_ypresp_maplist,
                                (char *)&maplist)) {
                RESPOND_ERR;
        }

        while (maplist.list) {
                tmp = maplist.list->ypml_next;
                free((char *)maplist.list);
                maplist.list = tmp;
        }
}

/*
 * Ancillary functions used by the top-level functions within this
 * module
 */

/*
 * This returns TRUE if a given key is a yp-private symbol, otherwise
 * FALSE
 */
static bool
isypsym(datum *key)
{
        if ((key->dptr == NULL) ||
                (key->dsize < yp_prefix_sz) ||
                memcmp(yp_prefix, key->dptr, yp_prefix_sz) ||
                (!memcmp(key->dptr, "YP_MULTI_", 9))) {
                return (FALSE);
        }
        return (TRUE);
}

/*
 * This provides private-symbol filtration for the enumeration functions.
 */
static void
ypfilter(DBM *fdb, datum *inkey, datum *outkey, datum *val, uint_t *status,
                                                        bool_t update)
{
        datum k;

        if (inkey) {

                if (isypsym(inkey)) {
                        *status = (unsigned)YP_BADARGS;
                        return;
                }

                k = dbm_do_nextkey(fdb, *inkey);
        } else {
                k = dbm_firstkey(fdb);
        }

        while (k.dptr && isypsym(&k)) {
                k = dbm_nextkey(fdb);
        }

        if (k.dptr == NULL) {
                *status = YP_NOMORE;
                return;
        }

        *outkey = k;

        /*
         * In N2L mode we must call a version of dbm_fetch() that either does
         * or does not check for entry updates. In non N2L mode both of these
         * will end up doing a normal dbm_fetch().
         */
        if (update)
                *val = shim_dbm_fetch(fdb, k);
        else
                *val = shim_dbm_fetch_noupdate(fdb, k);

        if (val->dptr != NULL) {
                *status = YP_TRUE;
        } else {
                *status = (unsigned)YP_BADDB;
        }
}

/*
 * Serializes a stream of struct ypresp_key_val's.  This is used
 * only by the ypserv side of the transaction.
 */
static bool
xdrypserv_ypall(XDR *xdrs, struct ypreq_nokey *req)
{
        bool_t more = TRUE;
        struct ypresp_key_val resp;
        DBM *fdb;

        resp.keydat.dptr = resp.valdat.dptr = (char *)NULL;
        resp.keydat.dsize = resp.valdat.dsize = 0;

        if ((fdb = ypset_current_map(req->map, req->domain,
                                        &resp.status)) != NULL) {
                ypfilter(fdb, (datum *) NULL, &resp.keydat, &resp.valdat,
                                &resp.status, FALSE);

                while (resp.status == YP_TRUE) {
                        if (!xdr_bool(xdrs, &more)) {
                                return (FALSE);
                        }

                        if (!xdr_ypresp_key_val(xdrs, &resp)) {
                                return (FALSE);
                        }

                        ypfilter(fdb, &resp.keydat, &resp.keydat, &resp.valdat,
                                        &resp.status, FALSE);
                }
        }

        if (!xdr_bool(xdrs, &more)) {
                return (FALSE);
        }

        if (!xdr_ypresp_key_val(xdrs, &resp)) {
                return (FALSE);
        }

        more = FALSE;

        if (!xdr_bool(xdrs, &more)) {
                return (FALSE);
        }

        return (TRUE);
}

/*
 * Additions for sparc cluster support
 */

/*
 * Check for special multihomed host cookie in the key.  If there,
 * collect the addresses from the comma separated list and return
 * the one that's nearest the client.
 */
static int
multihomed(struct ypreq_key req, struct ypresp_val *resp,
                SVCXPRT *xprt, DBM *fdb)
{
        char *cp, *bp;
        ulong_t bestaddr, call_addr;
        struct netbuf *nbuf;
        char name[PATH_MAX];
        static char localbuf[_PBLKSIZ]; /* buffer for multihomed IPv6 addr */

        if (strcmp(req.map, "hosts.byname") &&
                        strcmp(req.map, "ipnodes.byname"))
                /* default status is YP_NOKEY */
                return (0);

        if (strncmp(req.keydat.dptr, "YP_MULTI_", 9)) {
                datum tmpname;

                strncpy(name, "YP_MULTI_", 9);
                strncpy(name + 9, req.keydat.dptr, req.keydat.dsize);
                tmpname.dsize = req.keydat.dsize + 9;
                tmpname.dptr = name;
                resp->valdat = dbm_fetch(fdb, tmpname);
        } else {
                /*
                 * Return whole line (for debugging) if YP_MULTI_hostnam
                 * is specified.
                 */
                resp->valdat = dbm_fetch(fdb, req.keydat);
                if (resp->valdat.dptr != NULL)
                        return (1);
        }

        if (resp->valdat.dptr == NULL)
                return (0);

        strncpy(name, req.keydat.dptr, req.keydat.dsize);
        name[req.keydat.dsize] = NULL;

        if (strcmp(req.map, "ipnodes.byname") == 0) {
                /*
                 * This section handles multihomed IPv6 addresses.
                 * It returns all the IPv6 addresses one per line and only
                 * the requested hostname is returned.  NO aliases will be
                 * returned.  This is done exactly the same way DNS forwarding
                 * daemon handles multihomed hosts.
                 * New IPv6 enabled clients should be able to handle this
                 * information returned.  The sorting is also the client's
                 * responsibility.
                 */

                char *buf, *endbuf;

                if ((buf = strdup(resp->valdat.dptr)) == NULL) /* no memory */
                        return (0);
                if ((bp = strtok(buf, " \t")) == NULL) { /* no address field */
                        free(buf);
                        return (0);
                }
                if ((cp = strtok(NULL, "")) == NULL) { /* no host field */
                        free(buf);
                        return (0);
                }
                if ((cp = strtok(bp, ",")) != NULL) { /* multihomed host */
                        int bsize;

                        localbuf[0] = '\0';
                        bsize = sizeof (localbuf);
                        endbuf = localbuf;

                        while (cp) {
                                if ((strlen(cp) + strlen(name)) >= bsize) {
                                        /* out of range */
                                        break;
                                }
                                sprintf(endbuf, "%s %s\n", cp, name);
                                cp = strtok(NULL, ",");
                                endbuf = &endbuf[strlen(endbuf)];
                                bsize = &localbuf[sizeof (localbuf)] - endbuf;
                        }
                        resp->valdat.dptr = localbuf;
                        resp->valdat.dsize = strlen(localbuf);
                }

                free(buf);
                /* remove trailing newline */
                if (resp->valdat.dsize &&
                        resp->valdat.dptr[resp->valdat.dsize-1] == '\n') {
                        resp->valdat.dptr[resp->valdat.dsize-1] = '\0';
                        resp->valdat.dsize -= 1;
                }

                resp->status = YP_TRUE;
                return (1);
        }
        nbuf = svc_getrpccaller(xprt);
        /*
         * OK, now I have a netbuf structure which I'm supposed to
         * treat as opaque...  I hate transport independance!
         * So, we're just gonna doit wrong...  By wrong I mean that
         * we assume that the buf part of the netbuf structure is going
         * to be a sockaddr_in.  We'll then check the assumed family
         * member and hope that we find AF_INET in there...  if not
         * then we can't continue.
         */
        if (((struct sockaddr_in *)(nbuf->buf))->sin_family != AF_INET)
                return (0);

        call_addr = ((struct sockaddr_in *)(nbuf->buf))->sin_addr.s_addr;

        cp = resp->valdat.dptr;
        if ((bp = strtok(cp, " \t")) == NULL) /* no address field */
                return (0);
        if ((cp = strtok(NULL, "")) == NULL)  /* no host field */
                return (0);
        bp = strtok(bp, ",");

        bestaddr = inet_addr(bp);
        while (cp = strtok(NULL, ",")) {
                ulong_t taddr;

                taddr = inet_addr(cp);
                if (ntohl(call_addr ^ taddr) < ntohl(call_addr ^ bestaddr))
                        bestaddr = taddr;
        }
        cp = resp->valdat.dptr;
        sprintf(cp, "%s %s", inet_ntoa(*(struct in_addr *)&bestaddr), name);
        resp->valdat.dsize = strlen(cp);

        resp->status = YP_TRUE;

        return (1);
}

/* V1 dispatch routines */
void
ypoldmatch(SVCXPRT *transp, struct svc_req *rqstp)
{
        bool dbmop_ok = TRUE;
        struct yprequest req;
        struct ypreq_key nrq;
        struct ypresponse resp;
        char *fun = "ypoldmatch";
        DBM *fdb;

        memset((void *) &req, 0, sizeof (req));
        memset((void *) &resp, 0, sizeof (resp));

        if (!svc_getargs(transp,
                                (xdrproc_t)_xdr_yprequest,
                                (caddr_t)&req)) {
                svcerr_decode(transp);
                return;
        }

        if (req.yp_reqtype != YPMATCH_REQTYPE) {
                resp.ypmatch_resp_status = (unsigned)YP_BADARGS;
                dbmop_ok = FALSE;
        }

        if (dbmop_ok &&
                (((fdb = ypset_current_map(req.ypmatch_req_map,
                                                req.ypmatch_req_domain,
                                                &resp.ypmatch_resp_status))
                                                != NULL) &&
                                                yp_map_access(transp,
                                                &resp.ypmatch_resp_status,
                                                fdb))) {

                /* Check with the DBM database */
                resp.ypmatch_resp_valdat = dbm_fetch(fdb,
                                                req.ypmatch_req_keydat);

                if (resp.ypmatch_resp_valptr != NULL) {
                        resp.ypmatch_resp_status = YP_TRUE;
                        if (!silent)
                                printf("%s: dbm: %s\n",
                                        fun, resp.ypmatch_resp_valptr);
                        goto send_oldreply;
                }

                /*
                 * If we're being asked to match YP_SECURE or YP_INTERDOMAIN
                 * and we haven't found it in the dbm file, then we don't
                 * really want to waste any more time.  Specifically, we don't
                 * want to ask DNS
                 */
                if (req.ypmatch_req_keysize == 0 ||
                    req.ypmatch_req_keyptr == NULL ||
                    req.ypmatch_req_keyptr[0] == '\0' ||
                    strncmp(req.ypmatch_req_keyptr, "YP_SECURE", 9) == 0 ||
                    strncmp(req.ypmatch_req_keyptr, "YP_INTERDOMAIN", 14) == 0)

                    goto send_oldreply;

                /* Let's try the YP_MULTI_ hack... */
#ifdef MINUS_C_OPTION
                if (multiflag == TRUE && omultihomed(req, &resp, transp, fdb))
                        goto send_oldreply;
#else
                if (omultihomed(req, &resp, transp, fdb))
                        goto send_oldreply;
#endif

                /* Let's try DNS */
                if (!dnsforward) {
                        USE_YP_INTERDOMAIN
                        datum idkey, idval;
                        idkey.dptr = yp_interdomain;
                        idkey.dsize = yp_interdomain_sz;
                        idval = dbm_fetch(fdb, idkey);
                        if (idval.dptr)
                                dnsforward = TRUE;
                }

                if (dnsforward) {
                    if (!resolv_pid)
                        setup_resolv(&dnsforward, &resolv_pid, &resolv_client,
                                        resolv_tp, 0);

                    if (req.yp_reqtype == YPREQ_KEY) {
                        nrq = req.yp_reqbody.yp_req_keytype;

                        resolv_req(&dnsforward, &resolv_client, &resolv_pid,
                                        resolv_tp, rqstp->rq_xprt,
                                        &nrq, nrq.map);
                    }
                    return;
                }
        }

        send_oldreply:

        if (!svc_sendreply(transp,
                                (xdrproc_t)_xdr_ypresponse,
                                (caddr_t)&resp)) {
                RESPOND_ERR;
        }

        if (!svc_freeargs(transp,
                                (xdrproc_t)_xdr_yprequest,
                                (char *)&req)) {
                FREE_ERR;
        }
}

void
ypoldfirst(SVCXPRT *transp)
{
        bool dbmop_ok = TRUE;
        struct yprequest req;
        struct ypresponse resp;
        char *fun = "ypoldfirst";
        DBM *fdb;

        memset((void *) &req, 0, sizeof (req));
        memset((void *) &resp, 0, sizeof (resp));

        if (!svc_getargs(transp,
                                (xdrproc_t)_xdr_yprequest,
                                (caddr_t)&req)) {
                svcerr_decode(transp);
                return;
        }

        if (req.yp_reqtype != YPFIRST_REQTYPE) {
                resp.ypfirst_resp_status = (unsigned)YP_BADARGS;
                dbmop_ok = FALSE;
        }

        if (dbmop_ok &&
                ((fdb = ypset_current_map(req.ypfirst_req_map,
                                                req.ypfirst_req_domain,
                                                &resp.ypfirst_resp_status))
                                                != NULL) &&
                                                yp_map_access(transp,
                                                &resp.ypfirst_resp_status,
                                                fdb)) {

                resp.ypfirst_resp_keydat = dbm_firstkey(fdb);

                if (resp.ypfirst_resp_keyptr != NULL) {
                        resp.ypfirst_resp_valdat =
                                dbm_fetch(fdb, resp.ypfirst_resp_keydat);

                        if (resp.ypfirst_resp_valptr != NULL) {
                                resp.ypfirst_resp_status = YP_TRUE;
                        } else {
                                resp.ypfirst_resp_status = (unsigned)YP_BADDB;
                        }
                } else {
                        resp.ypfirst_resp_status = (unsigned)YP_NOKEY;
                }
        }

        resp.yp_resptype = YPFIRST_RESPTYPE;

        if (!svc_sendreply(transp,
                                (xdrproc_t)_xdr_ypresponse,
                                (caddr_t)&resp)) {
                RESPOND_ERR;
        }

        if (!svc_freeargs(transp,
                                (xdrproc_t)_xdr_yprequest,
                                (caddr_t)&req)) {
                FREE_ERR;
        }
}

void
ypoldnext(SVCXPRT *transp)
{
        bool dbmop_ok = TRUE;
        struct yprequest req;
        struct ypresponse resp;
        char *fun = "ypoldnext";
        DBM *fdb;

        memset((void *) &req, 0, sizeof (req));
        memset((void *) &resp, 0, sizeof (resp));

        if (!svc_getargs(transp,
                                (xdrproc_t)_xdr_yprequest,
                                (caddr_t)&req)) {
                svcerr_decode(transp);
                return;
        }

        if (req.yp_reqtype != YPNEXT_REQTYPE) {
                resp.ypnext_resp_status = (unsigned)YP_BADARGS;
                dbmop_ok = FALSE;
        }

        if (dbmop_ok &&
                ((fdb = ypset_current_map(req.ypnext_req_map,
                                        req.ypnext_req_domain,
                                        &resp.ypnext_resp_status)) != NULL &&
                yp_map_access(transp, &resp.ypnext_resp_status, fdb))) {

                resp.ypnext_resp_keydat = dbm_nextkey(fdb);

                if (resp.ypnext_resp_keyptr != NULL) {
                        resp.ypnext_resp_valdat =
                        dbm_fetch(fdb, resp.ypnext_resp_keydat);

                        if (resp.ypnext_resp_valptr != NULL) {
                                resp.ypnext_resp_status = YP_TRUE;
                        } else {
                                resp.ypnext_resp_status = (unsigned)YP_BADDB;
                        }
                } else {
                        resp.ypnext_resp_status = (unsigned)YP_NOMORE;
                }
        }

        resp.yp_resptype = YPNEXT_RESPTYPE;

        if (!svc_sendreply(transp,
                                (xdrproc_t)_xdr_ypresponse,
                                (caddr_t)&resp)) {
                RESPOND_ERR;
        }

        if (!svc_freeargs(transp,
                                (xdrproc_t)_xdr_yprequest,
                                (caddr_t)&req)) {
                FREE_ERR;
        }
}

/*
 * This retrieves the order number and master peer name from the map.
 * The conditions for the various message fields are: domain is filled
 * in iff the domain exists.  map is filled in iff the map exists.
 * order number is filled in iff it's in the map.  owner is filled in
 * iff the master peer is in the map.
 */
void
ypoldpoll(SVCXPRT *transp)
{
        struct yprequest req;
        struct ypresponse resp;
        char *map = "";
        char *domain = "";
        char *owner = "";
        uint_t error;
        char *fun = "ypoldpoll";
        DBM *fdb;

        memset((void *) &req, 0, sizeof (req));
        memset((void *) &resp, 0, sizeof (resp));

        if (!svc_getargs(transp,
                                (xdrproc_t)_xdr_yprequest,
                                (caddr_t)&req)) {
                svcerr_decode(transp);
                return;
        }

        if (req.yp_reqtype == YPPOLL_REQTYPE) {
                if (strcmp(req.yppoll_req_domain, "yp_private") == 0 ||
                        strcmp(req.yppoll_req_map, "ypdomains") == 0 ||
                        strcmp(req.yppoll_req_map, "ypmaps") == 0) {

                        /*
                         * Backward comatibility for 2.0 NIS servers
                         */
                        domain = req.yppoll_req_domain;
                        map = req.yppoll_req_map;
                } else if ((fdb = ypset_current_map(req.yppoll_req_map,
                                req.yppoll_req_domain,
                                &error)) != NULL) {
                        domain = req.yppoll_req_domain;
                        map = req.yppoll_req_map;
                        ypget_map_order(map, domain,
                                        &resp.yppoll_resp_ordernum);
                        ypget_map_master(&owner, fdb);
                } else {
                        switch ((int)error) {
                        case YP_BADDB:
                                map = req.yppoll_req_map;
                                /* Fall through to set the domain too. */

                        case YP_NOMAP:
                                domain = req.yppoll_req_domain;
                                break;
                        }
                }
        }

        resp.yp_resptype = YPPOLL_RESPTYPE;
        resp.yppoll_resp_domain = domain;
        resp.yppoll_resp_map = map;
        resp.yppoll_resp_owner = owner;

        if (!svc_sendreply(transp,
                                (xdrproc_t)_xdr_ypresponse,
                                (caddr_t)&resp)) {
                RESPOND_ERR;
        }

        if (!svc_freeargs(transp,
                                (xdrproc_t)_xdr_yprequest,
                                (caddr_t)&req)) {
                FREE_ERR;
        }
}

void
ypoldpush(SVCXPRT *transp)
{
        struct yprequest req;
        struct ypresp_val resp;
        pid_t pid = -1;
        char *fun = "ypoldpush";
        DBM *fdb;

        memset((void *) &req, 0, sizeof (req));

        if (!svc_getargs(transp,
                                (xdrproc_t)_xdr_yprequest,
                                (caddr_t)&req)) {
                svcerr_decode(transp);
                return;
        }

        if (((fdb = ypset_current_map(req.yppush_req_map,
                                        req.yppush_req_domain,
                                        &resp.status)) != NULL) &&
                (yp_map_access(transp, &resp.status, fdb))) {

                pid = vfork();
        }

        if (pid == -1) {
                FORK_ERR;
        } else if (pid == 0) {
                ypclr_current_map();

                if (execl(yppush_proc, "yppush", "-d", req.yppush_req_domain,
                                req.yppush_req_map, NULL)) {
                        EXEC_ERR;
                }
                _exit(1);
        }

        if (!svc_sendreply(transp,
                                (xdrproc_t)xdr_void,
                                (caddr_t)NULL)) {
                RESPOND_ERR;
        }

        if (!svc_freeargs(transp,
                                (xdrproc_t)_xdr_yprequest,
                                (caddr_t)&req)) {
                FREE_ERR;
        }
}

void
ypoldpull(SVCXPRT *transp)
{
        struct yprequest req;
        struct ypresp_val resp;
        pid_t pid = -1;
        char *fun = "ypoldpull";
        DBM *fdb;

        memset((void *) &req, 0, sizeof (req));

        if (!svc_getargs(transp,
                                (xdrproc_t)_xdr_yprequest,
                                (caddr_t)&req)) {
                svcerr_decode(transp);
                return;
        }

        if (req.yp_reqtype == YPPULL_REQTYPE) {

                if (((fdb = ypset_current_map(req.yppull_req_map,
                                                req.yppull_req_domain,
                                                &resp.status)) == NULL) ||
                        (yp_map_access(transp, &resp.status, fdb))) {
                        pid = vfork();
                }

                if (pid == -1) {
                        FORK_ERR;
                } else if (pid == 0) {
                        ypclr_current_map();

                        if (execl(ypxfr_proc, "ypxfr", "-d",
                                        req.yppull_req_domain,
                                        req.yppull_req_map, NULL)) {
                                EXEC_ERR;
                        }
                        _exit(1);
                }
        }

        if (!svc_freeargs(transp,
                                (xdrproc_t)_xdr_yprequest,
                                (caddr_t)&req)) {
                FREE_ERR;
        }
}

void
ypoldget(SVCXPRT *transp)
{
        struct yprequest req;
        struct ypresp_val resp;
        pid_t pid = -1;
        char *fun = "ypoldget";
        DBM *fdb;

        memset((void *) &req, 0, sizeof (req));

        if (!svc_getargs(transp,
                                (xdrproc_t)_xdr_yprequest,
                                (caddr_t)&req)) {
                svcerr_decode(transp);
                return;
        }

        if (!svc_sendreply(transp, xdr_void, 0)) {
                RESPOND_ERR;
        }

        if (req.yp_reqtype == YPGET_REQTYPE) {

                if (((fdb = ypset_current_map(req.ypget_req_map,
                                                req.ypget_req_domain,
                                                &resp.status)) == NULL) ||
                        (yp_map_access(transp, &resp.status, fdb))) {

                        pid = vfork();
                }

                if (pid == -1) {
                        FORK_ERR;
                } else if (pid == 0) {

                        ypclr_current_map();

                        if (execl(ypxfr_proc, "ypxfr", "-d",
                                        req.ypget_req_domain, "-h",
                                        req.ypget_req_owner,
                                        req.ypget_req_map, NULL)) {

                                EXEC_ERR;
                        }
                        _exit(1);
                }
        }

        if (!svc_freeargs(transp,
                                (xdrproc_t)_xdr_yprequest,
                                (caddr_t)&req)) {
                RESPOND_ERR;
        }
}

static int
omultihomed(struct yprequest req,
            struct ypresponse *resp, SVCXPRT *xprt, DBM *fdb)
{
        char *cp, *bp;
        char name[PATH_MAX];
        struct netbuf *nbuf;
        ulong_t bestaddr, call_addr;

        if (strcmp(req.ypmatch_req_map, "hosts.byname"))
                return (0);

        if (strncmp(req.ypmatch_req_keyptr, "YP_MULTI_", 9)) {
                datum tmpname;

                strncpy(name, "YP_MULTI_", 9);
                strncpy(name + 9, req.ypmatch_req_keyptr,
                        req.ypmatch_req_keysize);
                tmpname.dsize = req.ypmatch_req_keysize + 9;
                tmpname.dptr = name;
                resp->ypmatch_resp_valdat = dbm_fetch(fdb, tmpname);
        } else {
                resp->ypmatch_resp_valdat =
                        dbm_fetch(fdb, req.ypmatch_req_keydat);
                if (resp->ypmatch_resp_valptr != NULL)
                        return (1);
        }

        if (resp->ypmatch_resp_valptr == NULL)
                return (0);

        strncpy(name, req.ypmatch_req_keyptr, req.ypmatch_req_keysize);
        name[req.ypmatch_req_keysize] = NULL;

        nbuf = svc_getrpccaller(xprt);

        /*
         * OK, now I have a netbuf structure which I'm supposed to treat
         * as opaque...  I hate transport independance!  So, we're just
         * gonna doit wrong...  By wrong I mean that we assume that the
         * buf part of the netbuf structure is going to be a sockaddr_in.
         * We'll then check the assumed family member and hope that we
         * find AF_INET in there...  if not then we can't continue.
         */
        if (((struct sockaddr_in *)(nbuf->buf))->sin_family != AF_INET)
                return (0);

        call_addr = ((struct sockaddr_in *)(nbuf->buf))->sin_addr.s_addr;

        cp = resp->ypmatch_resp_valptr;
        if ((bp = strtok(cp, "\t")) == NULL)    /* No address field */
                return (0);
        if ((cp = strtok(NULL, "")) == NULL)    /* No host field */
                return (0);
        bp = strtok(bp, ",");

        bestaddr = inet_addr(bp);
        while (cp = strtok(NULL, ",")) {
                ulong_t taddr;

                taddr = inet_addr(cp);
                if (ntohl(call_addr ^ taddr) < ntohl(call_addr ^ bestaddr))
                        bestaddr = taddr;
        }

        cp = resp->ypmatch_resp_valptr;
        sprintf(cp, "%s %s", inet_ntoa(*(struct in_addr *)&bestaddr), name);
        resp->ypmatch_resp_valsize = strlen(cp);

        resp->ypmatch_resp_status = YP_TRUE;

        return (1);
}