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
  33 /*
  34  * Sun RPC is a product of Sun Microsystems, Inc. and is provided for
  35  * unrestricted use provided that this legend is included on all tape
  36  * media and as a part of the software program in whole or part.  Users
  37  * may copy or modify Sun RPC without charge, but are not authorized
  38  * to license or distribute it to anyone else except as part of a product or
  39  * program developed by the user.
  40  *
  41  * SUN RPC IS PROVIDED AS IS WITH NO WARRANTIES OF ANY KIND INCLUDING THE
  42  * WARRANTIES OF DESIGN, MERCHANTIBILITY AND FITNESS FOR A PARTICULAR
  43  * PURPOSE, OR ARISING FROM A COURSE OF DEALING, USAGE OR TRADE PRACTICE.
  44  *
  45  * Sun RPC is provided with no support and without any obligation on the
  46  * part of Sun Microsystems, Inc. to assist in its use, correction,
  47  * modification or enhancement.
  48  *
  49  * SUN MICROSYSTEMS, INC. SHALL HAVE NO LIABILITY WITH RESPECT TO THE
  50  * INFRINGEMENT OF COPYRIGHTS, TRADE SECRETS OR ANY PATENTS BY SUN RPC
  51  * OR ANY PART THEREOF.
  52  *
  53  * In no event will Sun Microsystems, Inc. be liable for any lost revenue
  54  * or profits or other special, indirect and consequential damages, even if
  55  * Sun has been advised of the possibility of such damages.
  56  *
  57  * Sun Microsystems, Inc.
  58  * 2550 Garcia Avenue
  59  * Mountain View, California  94043
  60  */
  61
  62 #if 0
  63 #ifndef lint
  64 static char *sccsid = "@(#)from: clnt_udp.c 1.39 87/08/11 Copyr 1984 Sun Micro";
  65 static char *sccsid = "@(#)from: clnt_udp.c     2.2 88/08/01 4.0 RPCSRC";
  66 #endif
  67 #endif
  68 #include <sys/cdefs.h>
  69 __FBSDID("$FreeBSD$");
  70
  71 /*
  72  * clnt_udp.c, Implements a UDP/IP based, client side RPC.
  73  *
  74  * Copyright (C) 1984, Sun Microsystems, Inc.
  75  */
  76
  77 #include <errno.h>
  78 #include <netdb.h>
  79 #include <stdio.h>
  80 #include <stdlib.h>
  81 #include <string.h>
  82 #include <unistd.h>
  83 #include <pthread.h>
  84 #include <rpc/rpc.h>
  85 #include <rpc/pmap_clnt.h>
  86 #include <rpc/pmap_prot.h>
  87 #include <rpcsvc/yp.h>
  88 #include <sys/types.h>
  89 #include <sys/poll.h>
  90 #include <sys/socket.h>
  91 #include <sys/signal.h>
  92 #include <sys/ioctl.h>
  93 #include <arpa/inet.h>
  94 #include <net/if.h>
  95
  96 #include "yp_ping.h"
  97
  98 struct cu_data {
  99         int                     cu_fd;          /* connections fd */
 100         bool_t                  cu_closeit;     /* opened by library */
 101         struct sockaddr_storage cu_raddr;       /* remote address */
 102         int                     cu_rlen;
 103         struct timeval          cu_wait;        /* retransmit interval */
 104         struct timeval          cu_total;       /* total time for the call */
 105         struct rpc_err          cu_error;
 106         XDR                     cu_outxdrs;
 107         u_int                   cu_xdrpos;
 108         u_int                   cu_sendsz;      /* send size */
 109         char                    *cu_outbuf;
 110         u_int                   cu_recvsz;      /* recv size */
 111         struct pollfd           pfdp;
 112         int                     cu_async;
 113         char                    cu_inbuf[1];
 114 };
 115
 116 /*
 117  * pmap_getport.c
 118  * Client interface to pmap rpc service.
 119  *
 120  * Copyright (C) 1984, Sun Microsystems, Inc.
 121  */
 122
 123
 124 static struct timeval timeout = { 1, 0 };
 125 static struct timeval tottimeout = { 1, 0 };
 126
 127 /*
 128  * Find the mapped port for program,version.
 129  * Calls the pmap service remotely to do the lookup.
 130  * Returns 0 if no map exists.
 131  */
 132 static u_short
 133 __pmap_getport(struct sockaddr_in *address, u_long program, u_long version,
 134     u_int protocol)
 135 {
 136         u_short port = 0;
 137         int sock = -1;
 138         register CLIENT *client;
 139         struct pmap parms;
 140
 141         address->sin_port = htons(PMAPPORT);
 142
 143         client = clntudp_bufcreate(address, PMAPPROG,
 144             PMAPVERS, timeout, &sock, RPCSMALLMSGSIZE, RPCSMALLMSGSIZE);
 145         if (client != (CLIENT *)NULL) {
 146                 parms.pm_prog = program;
 147                 parms.pm_vers = version;
 148                 parms.pm_prot = protocol;
 149                 parms.pm_port = 0;  /* not needed or used */
 150                 if (CLNT_CALL(client, PMAPPROC_GETPORT,
 151                         (xdrproc_t)xdr_pmap, &parms,
 152                         (xdrproc_t)xdr_u_short, &port,
 153                         tottimeout) != RPC_SUCCESS){
 154                         rpc_createerr.cf_stat = RPC_PMAPFAILURE;
 155                         clnt_geterr(client, &rpc_createerr.cf_error);
 156                 } else if (port == 0) {
 157                         rpc_createerr.cf_stat = RPC_PROGNOTREGISTERED;
 158                 }
 159                 CLNT_DESTROY(client);
 160         }
 161         if (sock != -1)
 162                 (void)close(sock);
 163         address->sin_port = 0;
 164         return (port);
 165 }
 166
 167 /*
 168  * Transmit to YPPROC_DOMAIN_NONACK, return immediately.
 169  */
 170 static bool_t *
 171 ypproc_domain_nonack_2_send(domainname *argp, CLIENT *clnt)
 172 {
 173         static bool_t clnt_res;
 174         struct timeval TIMEOUT = { 0, 0 };
 175
 176         memset((char *)&clnt_res, 0, sizeof (clnt_res));
 177         if (clnt_call(clnt, YPPROC_DOMAIN_NONACK,
 178                 (xdrproc_t) xdr_domainname, (caddr_t) argp,
 179                 (xdrproc_t) xdr_bool, (caddr_t) &clnt_res,
 180                 TIMEOUT) != RPC_SUCCESS) {
 181                 return (NULL);
 182         }
 183         return (&clnt_res);
 184 }
 185
 186 /*
 187  * Receive response from YPPROC_DOMAIN_NONACK asynchronously.
 188  */
 189 static bool_t *
 190 ypproc_domain_nonack_2_recv(domainname *argp, CLIENT *clnt)
 191 {
 192         static bool_t clnt_res;
 193         struct timeval TIMEOUT = { 0, 0 };
 194
 195         memset((char *)&clnt_res, 0, sizeof (clnt_res));
 196         if (clnt_call(clnt, YPPROC_DOMAIN_NONACK,
 197                 (xdrproc_t) NULL, (caddr_t) argp,
 198                 (xdrproc_t) xdr_bool, (caddr_t) &clnt_res,
 199                 TIMEOUT) != RPC_SUCCESS) {
 200                 return (NULL);
 201         }
 202         return (&clnt_res);
 203 }
 204
 205 /*
 206  * "We have the machine that goes 'ping!'" -- Monty Python
 207  *
 208  * This function blasts packets at the YPPROC_DOMAIN_NONACK procedures
 209  * of the NIS servers listed in restricted_addrs structure.
 210  * Whoever replies the fastest becomes our chosen server.
 211  *
 212  * Note: THIS IS NOT A BROADCAST OPERATION! We could use clnt_broadcast()
 213  * for this, but that has the following problems:
 214  * - We only get the address of the machine that replied in the
 215  *   'eachresult' callback, and on multi-homed machines this can
 216  *   lead to confusion.
 217  * - clnt_broadcast() only transmits to local networks, whereas with
 218  *   NIS+ you can have a perfectly good server located anywhere on or
 219  *   off the local network.
 220  * - clnt_broadcast() blocks for an arbitrary amount of time which the
 221  *   caller can't control -- we want to avoid that.
 222  *
 223  * Also note that this has nothing to do with the NIS_PING procedure used
 224  * for replica updates.
 225  */
 226
 227 struct ping_req {
 228         struct sockaddr_in      sin;
 229         u_int32_t               xid;
 230 };
 231
 232 int
 233 __yp_ping(struct in_addr *restricted_addrs, int cnt, char *dom, short *port)
 234 {
 235         struct timeval          tv = { 5, 0 };
 236         struct ping_req         **reqs;
 237         unsigned long           i;
 238         int                     async;
 239         struct sockaddr_in      sin, *any = NULL;
 240         int                     winner = -1;
 241         u_int32_t               xid_seed, xid_lookup;
 242         int                     sock, dontblock = 1;
 243         CLIENT                  *clnt;
 244         char                    *foo = dom;
 245         struct cu_data          *cu;
 246         int                     validsrvs = 0;
 247
 248         /* Set up handles. */
 249         reqs = calloc(1, sizeof(struct ping_req *) * cnt);
 250         xid_seed = time(NULL) ^ getpid();
 251
 252         for (i = 0; i < cnt; i++) {
 253                 bzero((char *)&sin, sizeof(sin));
 254                 sin.sin_family = AF_INET;
 255                 bcopy((char *)&restricted_addrs[i],
 256                         (char *)&sin.sin_addr, sizeof(struct in_addr));
 257                 sin.sin_port = htons(__pmap_getport(&sin, YPPROG,
 258                                         YPVERS, IPPROTO_UDP));
 259                 if (sin.sin_port == 0)
 260                         continue;
 261                 reqs[i] = calloc(1, sizeof(struct ping_req));
 262                 bcopy((char *)&sin, (char *)&reqs[i]->sin, sizeof(sin));
 263                 any = &reqs[i]->sin;
 264                 reqs[i]->xid = xid_seed;
 265                 xid_seed++;
 266                 validsrvs++;
 267         }
 268
 269         /* Make sure at least one server was assigned */
 270         if (!validsrvs) {
 271                 free(reqs);
 272                 return(-1);
 273         }
 274
 275         /* Create RPC handle */
 276         sock = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
 277         clnt = clntudp_create(any, YPPROG, YPVERS, tv, &sock);
 278         if (clnt == NULL) {
 279                 close(sock);
 280                 for (i = 0; i < cnt; i++)
 281                         if (reqs[i] != NULL)
 282                                 free(reqs[i]);
 283                 free(reqs);
 284                 return(-1);
 285         }
 286         clnt->cl_auth = authunix_create_default();
 287         cu = (struct cu_data *)clnt->cl_private;
 288         tv.tv_sec = 0;
 289
 290         clnt_control(clnt, CLSET_TIMEOUT, (char *)&tv);
 291         async = TRUE;
 292         clnt_control(clnt, CLSET_ASYNC, (char *)&async);
 293         ioctl(sock, FIONBIO, &dontblock);
 294
 295         /* Transmit */
 296         for (i = 0; i < cnt; i++) {
 297                 if (reqs[i] != NULL) {
 298                         clnt_control(clnt, CLSET_XID, (char *)&reqs[i]->xid);
 299                         bcopy((char *)&reqs[i]->sin, (char *)&cu->cu_raddr,
 300                                 sizeof(struct sockaddr_in));
 301                         ypproc_domain_nonack_2_send(&foo, clnt);
 302                 }
 303         }
 304
 305         /* Receive reply */
 306         ypproc_domain_nonack_2_recv(&foo, clnt);
 307
 308         /* Got a winner -- look him up. */
 309         clnt_control(clnt, CLGET_XID, (char *)&xid_lookup);
 310         for (i = 0; i < cnt; i++) {
 311                 if (reqs[i] != NULL && reqs[i]->xid == xid_lookup) {
 312                         winner = i;
 313                         *port = reqs[i]->sin.sin_port;
 314                 }
 315         }
 316
 317         /* Shut everything down */
 318         auth_destroy(clnt->cl_auth);
 319         clnt_destroy(clnt);
 320         close(sock);
 321
 322         for (i = 0; i < cnt; i++)
 323                 if (reqs[i] != NULL)
 324                         free(reqs[i]);
 325         free(reqs);
 326
 327         return(winner);
 328 }