utils/showmount/showmount.c

   1 /*
   2  * showmount.c -- show mount information for an NFS server
   3  * Copyright (C) 1993 Rick Sladkey <jrs@world.std.com>
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2, or (at your option)
   8  * any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  */
  15
  16 #ifdef HAVE_CONFIG_H
  17 #include <config.h>
  18 #endif
  19
  20 #include <stdio.h>
  21 #include <rpc/rpc.h>
  22 #include <rpc/pmap_prot.h>
  23 #include <sys/socket.h>
  24 #include <netinet/in.h>
  25 #include <sys/time.h>
  26 #include <string.h>
  27 #include <sys/types.h>
  28 #include <unistd.h>
  29 #include <memory.h>
  30 #include <stdlib.h>
  31 #include <fcntl.h>
  32
  33 #include <netdb.h>
  34 #include <arpa/inet.h>
  35 #include <errno.h>
  36 #include <getopt.h>
  37 #include <mount.h>
  38 #include <unistd.h>
  39
  40 #include "nfsrpc.h"
  41
  42 #define TIMEOUT_UDP     3
  43 #define TIMEOUT_TCP     10
  44 #define TOTAL_TIMEOUT   20
  45
  46 static char *   version = "showmount for " VERSION;
  47 static char *   program_name;
  48 static int      headers = 1;
  49 static int      hflag = 0;
  50 static int      aflag = 0;
  51 static int      dflag = 0;
  52 static int      eflag = 0;
  53
  54 static struct option longopts[] =
  55 {
  56         { "all", 0, 0, 'a' },
  57         { "directories", 0, 0, 'd' },
  58         { "exports", 0, 0, 'e' },
  59         { "no-headers", 0, &headers, 0 },
  60         { "version", 0, 0, 'v' },
  61         { "help", 0, 0, 'h' },
  62         { NULL, 0, 0, 0 }
  63 };
  64
  65 #define MAXHOSTLEN 256
  66
  67 static int dump_cmp(const void *pv, const void *qv)
  68 {
  69         const char **p = (const char **)pv;
  70         const char **q = (const char **)qv;
  71         return strcmp(*p, *q);
  72 }
  73
  74 static void usage(FILE *fp, int n)
  75 {
  76         fprintf(fp, "Usage: %s [-adehv]\n", program_name);
  77         fprintf(fp, "       [--all] [--directories] [--exports]\n");
  78         fprintf(fp, "       [--no-headers] [--help] [--version] [host]\n");
  79         exit(n);
  80 }
  81
  82 /*
  83  *  Perform a non-blocking connect on the socket fd.
  84  *
  85  *  tout contains the timeout.  It will be modified to contain the time
  86  *  remaining (i.e. time provided - time elasped).
  87  *
  88  *  Returns zero on success; otherwise, -1 is returned and errno is set
  89  *  to reflect the nature of the error.
  90  */
  91 static int connect_nb(int fd, struct sockaddr_in *addr, struct timeval *tout)
  92 {
  93         int flags, ret;
  94         socklen_t len;
  95         fd_set rset;
  96
  97         flags = fcntl(fd, F_GETFL, 0);
  98         if (flags < 0)
  99                 return -1;
 100
 101         ret = fcntl(fd, F_SETFL, flags | O_NONBLOCK);
 102         if (ret < 0)
 103                 return -1;
 104
 105         /*
 106          * From here on subsequent sys calls could change errno so
 107          * we set ret = -errno to capture it in case we decide to
 108          * use it later.
 109          */
 110         len = sizeof(struct sockaddr);
 111         ret = connect(fd, (struct sockaddr *)addr, len);
 112         if (ret < 0 && errno != EINPROGRESS) {
 113                 ret = -1;
 114                 goto done;
 115         }
 116
 117         if (ret == 0)
 118                 goto done;
 119
 120         /* now wait */
 121         FD_ZERO(&rset);
 122         FD_SET(fd, &rset);
 123
 124         ret = select(fd + 1, NULL, &rset, NULL, tout);
 125         if (ret <= 0) {
 126                 if (ret == 0)
 127                         errno = ETIMEDOUT;
 128                 ret = -1;
 129                 goto done;
 130         }
 131
 132         if (FD_ISSET(fd, &rset)) {
 133                 int status;
 134
 135                 len = sizeof(ret);
 136                 status = getsockopt(fd, SOL_SOCKET, SO_ERROR, &ret, &len);
 137                 if (status < 0) {
 138                         ret = -1;
 139                         goto done;
 140                 }
 141
 142                 /* Oops - something wrong with connect */
 143                 if (ret != 0) {
 144                         errno = ret;
 145                         ret = -1;
 146                 }
 147         }
 148
 149 done:
 150         fcntl(fd, F_SETFL, flags);
 151         return ret;
 152 }
 153
 154 static unsigned short getport(struct sockaddr_in *addr,
 155                          unsigned long prog, unsigned long vers, int prot)
 156 {
 157         CLIENT *client;
 158         enum clnt_stat status;
 159         struct pmap parms;
 160         int ret, sock;
 161         struct sockaddr_in laddr, saddr;
 162         struct timeval tout = {0, 0};
 163         socklen_t len;
 164         unsigned int send_sz = 0;
 165         unsigned int recv_sz = 0;
 166         unsigned short port;
 167
 168         memset(&laddr, 0, sizeof(laddr));
 169         memset(&saddr, 0, sizeof(saddr));
 170         memset(&parms, 0, sizeof(parms));
 171
 172         memcpy(&saddr, addr, sizeof(saddr));
 173         saddr.sin_port = htons(PMAPPORT);
 174
 175         if (prot == IPPROTO_TCP) {
 176                 sock = socket(PF_INET, SOCK_STREAM, IPPROTO_TCP);
 177                 if (sock == -1) {
 178                         rpc_createerr.cf_stat = RPC_SYSTEMERROR;
 179                         rpc_createerr.cf_error.re_errno = errno;
 180                         return 0;
 181                 }
 182
 183                 tout.tv_sec = TIMEOUT_TCP;
 184
 185                 ret = connect_nb(sock, &saddr, &tout);
 186                 if (ret != 0) {
 187                         rpc_createerr.cf_stat = RPC_SYSTEMERROR;
 188                         rpc_createerr.cf_error.re_errno = errno;
 189                         close(sock);
 190                         return 0;
 191                 }
 192                 client = clnttcp_create(&saddr,
 193                                         PMAPPROG, PMAPVERS, &sock,
 194                                         0, 0);
 195         } else {
 196                 /*
 197                  * bind to any unused port.  If we left this up to the rpc
 198                  * layer, it would bind to a reserved port, which has been shown
 199                  * to exhaust the reserved port range in some situations.
 200                  */
 201                 sock = socket(PF_INET, SOCK_DGRAM, IPPROTO_UDP);
 202                 if (sock == -1) {
 203                         rpc_createerr.cf_stat = RPC_SYSTEMERROR;
 204                         rpc_createerr.cf_error.re_errno = errno;
 205                         return 0;
 206                 }
 207
 208                 laddr.sin_family = AF_INET;
 209                 laddr.sin_port = 0;
 210                 laddr.sin_addr.s_addr = htonl(INADDR_ANY);
 211
 212                 tout.tv_sec = TIMEOUT_UDP;
 213
 214                 send_sz = RPCSMALLMSGSIZE;
 215                 recv_sz = RPCSMALLMSGSIZE;
 216
 217                 len = sizeof(struct sockaddr_in);
 218                 if (bind(sock, (struct sockaddr *)&laddr, len) < 0) {
 219                         close(sock);
 220                         sock = RPC_ANYSOCK;
 221                         /* FALLTHROUGH */
 222                 }
 223                 client = clntudp_bufcreate(&saddr, PMAPPROG, PMAPVERS,
 224                                            tout, &sock, send_sz, recv_sz);
 225         }
 226
 227         if (!client) {
 228                 close(sock);
 229                 rpc_createerr.cf_stat = RPC_RPCBFAILURE;
 230                 return 0;
 231         }
 232
 233         clnt_control(client, CLSET_FD_CLOSE, NULL);
 234
 235         parms.pm_prog = prog;
 236         parms.pm_vers = vers;
 237         parms.pm_prot = prot;
 238
 239         status = clnt_call(client, PMAPPROC_GETPORT,
 240                            (xdrproc_t) xdr_pmap, (caddr_t) &parms,
 241                            (xdrproc_t) xdr_u_short, (caddr_t) &port,
 242                            tout);
 243
 244         if (status != RPC_SUCCESS) {
 245                 clnt_geterr(client, &rpc_createerr.cf_error);
 246                 rpc_createerr.cf_stat = status;
 247                 clnt_destroy(client);
 248                 return 0;
 249         } else if (port == 0) {
 250                 rpc_createerr.cf_stat = RPC_PROGNOTREGISTERED;
 251         }
 252
 253         clnt_destroy(client);
 254
 255         return htons(port);
 256 }
 257
 258 int main(int argc, char **argv)
 259 {
 260         char hostname_buf[MAXHOSTLEN];
 261         char *hostname;
 262         enum clnt_stat clnt_stat;
 263         struct hostent *hp;
 264         struct sockaddr_in server_addr;
 265         int ret, msock;
 266         struct timeval total_timeout;
 267         struct timeval pertry_timeout;
 268         int c;
 269         CLIENT *mclient;
 270         groups grouplist;
 271         exports exportlist, exl;
 272         mountlist dumplist;
 273         mountlist list;
 274         int i;
 275         int n;
 276         int maxlen;
 277         char **dumpv;
 278
 279         program_name = argv[0];
 280         while ((c = getopt_long(argc, argv, "adehv", longopts, NULL)) != EOF) {
 281                 switch (c) {
 282                 case 'a':
 283                         aflag = 1;
 284                         break;
 285                 case 'd':
 286                         dflag = 1;
 287                         break;
 288                 case 'e':
 289                         eflag = 1;
 290                         break;
 291                 case 'h':
 292                         usage(stdout, 0);
 293                         break;
 294                 case 'v':
 295                         printf("%s\n", version);
 296                         exit(0);
 297                 case 0:
 298                         break;
 299                 case '?':
 300                 default:
 301                         usage(stderr, 1);
 302                         break;
 303                 }
 304         }
 305         argc -= optind;
 306         argv += optind;
 307
 308         switch (aflag + dflag + eflag) {
 309         case 0:
 310                 hflag = 1;
 311                 break;
 312         case 1:
 313                 break;
 314         default:
 315                 fprintf(stderr, "%s: only one of -a, -d or -e is allowed\n",
 316                         program_name);
 317                 exit(1);
 318                 break;
 319         }
 320
 321         switch (argc) {
 322         case 0:
 323                 if (gethostname(hostname_buf, MAXHOSTLEN) < 0) {
 324                         perror("getting hostname");
 325                         exit(1);
 326                 }
 327                 hostname = hostname_buf;
 328                 break;
 329         case 1:
 330                 hostname = argv[0];
 331                 break;
 332         default:
 333                 fprintf(stderr, "%s: only one hostname is allowed\n",
 334                         program_name);
 335                 exit(1);
 336                 break;
 337         }
 338
 339         if (inet_aton(hostname, &server_addr.sin_addr)) {
 340                 server_addr.sin_family = AF_INET;
 341         }
 342         else {
 343                 if ((hp = gethostbyname(hostname)) == NULL) {
 344                         fprintf(stderr, "%s: can't get address for %s\n",
 345                                 program_name, hostname);
 346                         exit(1);
 347                 }
 348                 server_addr.sin_family = AF_INET;
 349                 memcpy(&server_addr.sin_addr, hp->h_addr, hp->h_length);
 350         }
 351
 352         /* create mount deamon client */
 353
 354         mclient = NULL;
 355         msock = socket(PF_INET, SOCK_STREAM, IPPROTO_TCP);
 356         if (msock != -1) {
 357                 if (nfs_getport_ping((struct sockaddr *)&server_addr,
 358                                         sizeof(server_addr), MOUNTPROG,
 359                                         MOUNTVERS, IPPROTO_TCP)) {
 360                         ret = connect_nb(msock, &server_addr, 0);
 361                         if (ret == 0) /* success */
 362                                 mclient = clnttcp_create(&server_addr,
 363                                                 MOUNTPROG, MOUNTVERS, &msock,
 364                                                 0, 0);
 365                         else
 366                                 close(msock);
 367                 } else
 368                         close(msock);
 369         }
 370
 371         if (!mclient) {
 372                 if (nfs_getport_ping((struct sockaddr *)&server_addr,
 373                                         sizeof(server_addr), MOUNTPROG,
 374                                         MOUNTVERS, IPPROTO_UDP)) {
 375                         clnt_pcreateerror("showmount");
 376                         exit(1);
 377                 }
 378                 msock = RPC_ANYSOCK;
 379                 pertry_timeout.tv_sec = TIMEOUT_UDP;
 380                 pertry_timeout.tv_usec = 0;
 381                 if ((mclient = clntudp_create(&server_addr,
 382                     MOUNTPROG, MOUNTVERS, pertry_timeout, &msock)) == NULL) {
 383                         clnt_pcreateerror("mount clntudp_create");
 384                         exit(1);
 385                 }
 386         }
 387         mclient->cl_auth = authunix_create_default();
 388         total_timeout.tv_sec = TOTAL_TIMEOUT;
 389         total_timeout.tv_usec = 0;
 390
 391         if (eflag) {
 392                 memset(&exportlist, '\0', sizeof(exportlist));
 393
 394                 clnt_stat = clnt_call(mclient, MOUNTPROC_EXPORT,
 395                         (xdrproc_t) xdr_void, NULL,
 396                         (xdrproc_t) xdr_exports, (caddr_t) &exportlist,
 397                         total_timeout);
 398                 if (clnt_stat != RPC_SUCCESS) {
 399                         clnt_perror(mclient, "rpc mount export");
 400                         clnt_destroy(mclient);
 401                         exit(1);
 402                 }
 403                 if (headers)
 404                         printf("Export list for %s:\n", hostname);
 405                 maxlen = 0;
 406                 for (exl = exportlist; exl; exl = exl->ex_next) {
 407                         if ((n = strlen(exl->ex_dir)) > maxlen)
 408                                 maxlen = n;
 409                 }
 410                 while (exportlist) {
 411                         printf("%-*s ", maxlen, exportlist->ex_dir);
 412                         grouplist = exportlist->ex_groups;
 413                         if (grouplist)
 414                                 while (grouplist) {
 415                                         printf("%s%s", grouplist->gr_name,
 416                                                 grouplist->gr_next ? "," : "");
 417                                         grouplist = grouplist->gr_next;
 418                                 }
 419                         else
 420                                 printf("(everyone)");
 421                         printf("\n");
 422                         exportlist = exportlist->ex_next;
 423                 }
 424                 clnt_destroy(mclient);
 425                 exit(0);
 426         }
 427
 428         memset(&dumplist, '\0', sizeof(dumplist));
 429         clnt_stat = clnt_call(mclient, MOUNTPROC_DUMP,
 430                 (xdrproc_t) xdr_void, NULL,
 431                 (xdrproc_t) xdr_mountlist, (caddr_t) &dumplist,
 432                 total_timeout);
 433         if (clnt_stat != RPC_SUCCESS) {
 434                 clnt_perror(mclient, "rpc mount dump");
 435                 clnt_destroy(mclient);
 436                 exit(1);
 437         }
 438         clnt_destroy(mclient);
 439
 440         n = 0;
 441         for (list = dumplist; list; list = list->ml_next)
 442                 n++;
 443         dumpv = (char **) calloc(n, sizeof (char *));
 444         if (n && !dumpv) {
 445                 fprintf(stderr, "%s: out of memory\n", program_name);
 446                 exit(1);
 447         }
 448         i = 0;
 449
 450         if (hflag) {
 451                 if (headers)
 452                         printf("Hosts on %s:\n", hostname);
 453                 while (dumplist) {
 454                         dumpv[i++] = dumplist->ml_hostname;
 455                         dumplist = dumplist->ml_next;
 456                 }
 457         }
 458         else if (aflag) {
 459                 if (headers)
 460                         printf("All mount points on %s:\n", hostname);
 461                 while (dumplist) {
 462                         char *t;
 463
 464                         t=malloc(strlen(dumplist->ml_hostname)+strlen(dumplist->ml_directory)+2);
 465                         if (!t)
 466                         {
 467                                 fprintf(stderr, "%s: out of memory\n", program_name);
 468                                 exit(1);
 469                         }
 470                         sprintf(t, "%s:%s", dumplist->ml_hostname, dumplist->ml_directory);
 471                         dumpv[i++] = t;
 472                         dumplist = dumplist->ml_next;
 473                 }
 474         }
 475         else if (dflag) {
 476                 if (headers)
 477                         printf("Directories on %s:\n", hostname);
 478                 while (dumplist) {
 479                         dumpv[i++] = dumplist->ml_directory;
 480                         dumplist = dumplist->ml_next;
 481                 }
 482         }
 483
 484         qsort(dumpv, n, sizeof (char *), dump_cmp);
 485
 486         for (i = 0; i < n; i++) {
 487                 if (i == 0 || strcmp(dumpv[i], dumpv[i - 1]) != 0)
 488                         printf("%s\n", dumpv[i]);
 489         }
 490         exit(0);
 491 }
 492