usr.sbin/ypbind/yp_ping.c

   1 /*
   2  * Copyright (c) 1996, 1997
   3  *      Bill Paul <wpaul@ctr.columbia.edu>.  All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  * 3. All advertising materials mentioning features or use of this software
  14  *    must display the following acknowledgement:
  15  *      This product includes software developed by Bill Paul.
  16  * 4. Neither the name of the author nor the names of any co-contributors
  17  *    may be used to endorse or promote products derived from this software
  18  *    without specific prior written permission.
  19  *
  20  * THIS SOFTWARE IS PROVIDED BY Bill Paul AND CONTRIBUTORS ``AS IS'' AND
  21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  23  * ARE DISCLAIMED.  IN NO EVENT SHALL Bill Paul OR CONTRIBUTORS BE LIABLE
  24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  30  * SUCH DAMAGE.
  31  *
  32  * @(#)from: clnt_udp.c 1.39 87/08/11 Copyr 1984 Sun Micro
  33  * @(#)from: clnt_udp.c 2.2 88/08/01 4.0 RPCSRC
  34  * $FreeBSD: src/usr.sbin/ypbind/yp_ping.c,v 1.17 2008/09/15 14:01:40 dfr Exp $
  35  */
  36
  37 /*
  38  * Sun RPC is a product of Sun Microsystems, Inc. and is provided for
  39  * unrestricted use provided that this legend is included on all tape
  40  * media and as a part of the software program in whole or part.  Users
  41  * may copy or modify Sun RPC without charge, but are not authorized
  42  * to license or distribute it to anyone else except as part of a product or
  43  * program developed by the user.
  44  *
  45  * SUN RPC IS PROVIDED AS IS WITH NO WARRANTIES OF ANY KIND INCLUDING THE
  46  * WARRANTIES OF DESIGN, MERCHANTIBILITY AND FITNESS FOR A PARTICULAR
  47  * PURPOSE, OR ARISING FROM A COURSE OF DEALING, USAGE OR TRADE PRACTICE.
  48  *
  49  * Sun RPC is provided with no support and without any obligation on the
  50  * part of Sun Microsystems, Inc. to assist in its use, correction,
  51  * modification or enhancement.
  52  *
  53  * SUN MICROSYSTEMS, INC. SHALL HAVE NO LIABILITY WITH RESPECT TO THE
  54  * INFRINGEMENT OF COPYRIGHTS, TRADE SECRETS OR ANY PATENTS BY SUN RPC
  55  * OR ANY PART THEREOF.
  56  *
  57  * In no event will Sun Microsystems, Inc. be liable for any lost revenue
  58  * or profits or other special, indirect and consequential damages, even if
  59  * Sun has been advised of the possibility of such damages.
  60  *
  61  * Sun Microsystems, Inc.
  62  * 2550 Garcia Avenue
  63  * Mountain View, California  94043
  64  */
  65
  66 /*
  67  * clnt_udp.c, Implements a UDP/IP based, client side RPC.
  68  *
  69  * Copyright (C) 1984, Sun Microsystems, Inc.
  70  */
  71
  72 #include <errno.h>
  73 #include <netdb.h>
  74 #include <stdio.h>
  75 #include <stdlib.h>
  76 #include <string.h>
  77 #include <unistd.h>
  78 #include <pthread.h>
  79 #include <rpc/rpc.h>
  80 #include <rpc/pmap_clnt.h>
  81 #include <rpc/pmap_prot.h>
  82 #include <rpcsvc/yp.h>
  83 #include <sys/types.h>
  84 #include <sys/poll.h>
  85 #include <sys/socket.h>
  86 #include <sys/signal.h>
  87 #include <sys/ioctl.h>
  88 #include <arpa/inet.h>
  89 #include <net/if.h>
  90
  91 #include "yp_ping.h"
  92
  93 /*
  94  * pmap_getport.c
  95  * Client interface to pmap rpc service.
  96  *
  97  * Copyright (C) 1984, Sun Microsystems, Inc.
  98  */
  99
 100
 101 static struct timeval timeout = { 1, 0 };
 102 static struct timeval tottimeout = { 1, 0 };
 103
 104 /*
 105  * Find the mapped port for program,version.
 106  * Calls the pmap service remotely to do the lookup.
 107  * Returns 0 if no map exists.
 108  */
 109 static u_short
 110 __pmap_getport(struct sockaddr_in *address, u_long program, u_long version,
 111                u_int protocol)
 112 {
 113         u_short port = 0;
 114         int sock = -1;
 115         CLIENT *client;
 116         struct pmap parms;
 117
 118         address->sin_port = htons(PMAPPORT);
 119
 120         client = clntudp_bufcreate(address, PMAPPROG,
 121             PMAPVERS, timeout, &sock, RPCSMALLMSGSIZE, RPCSMALLMSGSIZE);
 122         if (client != NULL) {
 123                 parms.pm_prog = program;
 124                 parms.pm_vers = version;
 125                 parms.pm_prot = protocol;
 126                 parms.pm_port = 0;  /* not needed or used */
 127                 if (CLNT_CALL(client, PMAPPROC_GETPORT,
 128                         (xdrproc_t)xdr_pmap, &parms,
 129                         (xdrproc_t)xdr_u_short, &port,
 130                         tottimeout) != RPC_SUCCESS){
 131                         rpc_createerr.cf_stat = RPC_PMAPFAILURE;
 132                         clnt_geterr(client, &rpc_createerr.cf_error);
 133                 } else if (port == 0) {
 134                         rpc_createerr.cf_stat = RPC_PROGNOTREGISTERED;
 135                 }
 136                 CLNT_DESTROY(client);
 137         }
 138         if (sock != -1)
 139                 close(sock);
 140         address->sin_port = 0;
 141         return (port);
 142 }
 143
 144 /*
 145  * Transmit to YPPROC_DOMAIN_NONACK, return immediately.
 146  */
 147 static bool_t *
 148 ypproc_domain_nonack_2_send(domainname *argp, CLIENT *clnt)
 149 {
 150         static bool_t clnt_res;
 151         struct timeval TIMEOUT = { 0, 0 };
 152
 153         memset((char *)&clnt_res, 0, sizeof (clnt_res));
 154         if (clnt_call(clnt, YPPROC_DOMAIN_NONACK,
 155                 (xdrproc_t) xdr_domainname, (caddr_t) argp,
 156                 (xdrproc_t) xdr_bool, (caddr_t) &clnt_res,
 157                 TIMEOUT) != RPC_SUCCESS) {
 158                 return (NULL);
 159         }
 160         return (&clnt_res);
 161 }
 162
 163 /*
 164  * Receive response from YPPROC_DOMAIN_NONACK asynchronously.
 165  */
 166 static bool_t *
 167 ypproc_domain_nonack_2_recv(domainname *argp, CLIENT *clnt)
 168 {
 169         static bool_t clnt_res;
 170         struct timeval TIMEOUT = { 0, 0 };
 171
 172         memset((char *)&clnt_res, 0, sizeof (clnt_res));
 173         if (clnt_call(clnt, YPPROC_DOMAIN_NONACK,
 174                 NULL, (caddr_t) argp,
 175                 (xdrproc_t) xdr_bool, (caddr_t) &clnt_res,
 176                 TIMEOUT) != RPC_SUCCESS) {
 177                 return (NULL);
 178         }
 179         return (&clnt_res);
 180 }
 181
 182 /*
 183  * "We have the machine that goes 'ping!'" -- Monty Python
 184  *
 185  * This function blasts packets at the YPPROC_DOMAIN_NONACK procedures
 186  * of the NIS servers listed in restricted_addrs structure.
 187  * Whoever replies the fastest becomes our chosen server.
 188  *
 189  * Note: THIS IS NOT A BROADCAST OPERATION! We could use clnt_broadcast()
 190  * for this, but that has the following problems:
 191  * - We only get the address of the machine that replied in the
 192  *   'eachresult' callback, and on multi-homed machines this can
 193  *   lead to confusion.
 194  * - clnt_broadcast() only transmits to local networks, whereas with
 195  *   NIS+ you can have a perfectly good server located anywhere on or
 196  *   off the local network.
 197  * - clnt_broadcast() blocks for an arbitrary amount of time which the
 198  *   caller can't control -- we want to avoid that.
 199  *
 200  * Also note that this has nothing to do with the NIS_PING procedure used
 201  * for replica updates.
 202  */
 203
 204 struct ping_req {
 205         struct sockaddr_in      sin;
 206         u_int32_t               xid;
 207 };
 208
 209 int
 210 __yp_ping(struct in_addr *restricted_addrs, int cnt, char *dom, short *port)
 211 {
 212         struct timeval          tv = { 5, 0 };
 213         struct ping_req         **reqs;
 214         unsigned long           i;
 215         int                     async;
 216         struct sockaddr_in      sin, *any = NULL;
 217         struct netbuf           addr;
 218         int                     winner = -1;
 219         u_int32_t               xid_seed, xid_lookup;
 220         int                     sock, dontblock = 1;
 221         CLIENT                  *clnt;
 222         char                    *foo = dom;
 223         int                     validsrvs = 0;
 224
 225         /* Set up handles. */
 226         reqs = calloc(1, sizeof(struct ping_req *) * cnt);
 227         xid_seed = time(NULL) ^ getpid();
 228
 229         for (i = 0; i < cnt; i++) {
 230                 bzero((char *)&sin, sizeof(sin));
 231                 sin.sin_family = AF_INET;
 232                 bcopy((char *)&restricted_addrs[i],
 233                         (char *)&sin.sin_addr, sizeof(struct in_addr));
 234                 sin.sin_port = htons(__pmap_getport(&sin, YPPROG,
 235                                         YPVERS, IPPROTO_UDP));
 236                 if (sin.sin_port == 0)
 237                         continue;
 238                 reqs[i] = calloc(1, sizeof(struct ping_req));
 239                 bcopy((char *)&sin, (char *)&reqs[i]->sin, sizeof(sin));
 240                 any = &reqs[i]->sin;
 241                 reqs[i]->xid = xid_seed;
 242                 xid_seed++;
 243                 validsrvs++;
 244         }
 245
 246         /* Make sure at least one server was assigned */
 247         if (!validsrvs) {
 248                 free(reqs);
 249                 return(-1);
 250         }
 251
 252         /* Create RPC handle */
 253         sock = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
 254         clnt = clntudp_create(any, YPPROG, YPVERS, tv, &sock);
 255         if (clnt == NULL) {
 256                 close(sock);
 257                 for (i = 0; i < cnt; i++)
 258                         if (reqs[i] != NULL)
 259                                 free(reqs[i]);
 260                 free(reqs);
 261                 return(-1);
 262         }
 263         clnt->cl_auth = authunix_create_default();
 264         tv.tv_sec = 0;
 265
 266         clnt_control(clnt, CLSET_TIMEOUT, (char *)&tv);
 267         async = TRUE;
 268         clnt_control(clnt, CLSET_ASYNC, (char *)&async);
 269         ioctl(sock, FIONBIO, &dontblock);
 270
 271         /* Transmit */
 272         for (i = 0; i < cnt; i++) {
 273                 if (reqs[i] != NULL) {
 274                         clnt_control(clnt, CLSET_XID, (char *)&reqs[i]->xid);
 275                         addr.len = sizeof(reqs[i]->sin);
 276                         addr.buf = (char *) &reqs[i]->sin;
 277                         clnt_control(clnt, CLSET_SVC_ADDR, &addr);
 278                         ypproc_domain_nonack_2_send(&foo, clnt);
 279                 }
 280         }
 281
 282         /* Receive reply */
 283         ypproc_domain_nonack_2_recv(&foo, clnt);
 284
 285         /* Got a winner -- look him up. */
 286         clnt_control(clnt, CLGET_XID, (char *)&xid_lookup);
 287         for (i = 0; i < cnt; i++) {
 288                 if (reqs[i] != NULL && reqs[i]->xid == xid_lookup) {
 289                         winner = i;
 290                         *port = reqs[i]->sin.sin_port;
 291                 }
 292         }
 293
 294         /* Shut everything down */
 295         auth_destroy(clnt->cl_auth);
 296         clnt_destroy(clnt);
 297         close(sock);
 298
 299         for (i = 0; i < cnt; i++)
 300                 if (reqs[i] != NULL)
 301                         free(reqs[i]);
 302         free(reqs);
 303
 304         return(winner);
 305 }