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