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 TOTAL_TIMEOUT   20
  44
  45 static char *   version = "showmount for " VERSION;
  46 static char *   program_name;
  47 static int      headers = 1;
  48 static int      hflag = 0;
  49 static int      aflag = 0;
  50 static int      dflag = 0;
  51 static int      eflag = 0;
  52
  53 static const char *nfs_sm_pgmtbl[] = {
  54         "showmount",
  55         "mount",
  56         "mountd",
  57         NULL,
  58 };
  59
  60 static struct option longopts[] =
  61 {
  62         { "all", 0, 0, 'a' },
  63         { "directories", 0, 0, 'd' },
  64         { "exports", 0, 0, 'e' },
  65         { "no-headers", 0, &headers, 0 },
  66         { "version", 0, 0, 'v' },
  67         { "help", 0, 0, 'h' },
  68         { NULL, 0, 0, 0 }
  69 };
  70
  71 #define MAXHOSTLEN 256
  72
  73 static int dump_cmp(const void *pv, const void *qv)
  74 {
  75         const char **p = (const char **)pv;
  76         const char **q = (const char **)qv;
  77         return strcmp(*p, *q);
  78 }
  79
  80 static void usage(FILE *fp, int n)
  81 {
  82         fprintf(fp, "Usage: %s [-adehv]\n", program_name);
  83         fprintf(fp, "       [--all] [--directories] [--exports]\n");
  84         fprintf(fp, "       [--no-headers] [--help] [--version] [host]\n");
  85         exit(n);
  86 }
  87
  88 #ifdef HAVE_CLNT_CREATE
  89
  90 /*
  91  * Generate an RPC client handle connected to the mountd service
  92  * at @hostname, or die trying.
  93  *
  94  * Supports both AF_INET and AF_INET6 server addresses.
  95  */
  96 static CLIENT *nfs_get_mount_client(const char *hostname)
  97 {
  98         rpcprog_t program = nfs_getrpcbyname(MOUNTPROG, nfs_sm_pgmtbl);
  99         CLIENT *client;
 100
 101         client = clnt_create(hostname, program, MOUNTVERS, "tcp");
 102         if (client)
 103                 return client;
 104
 105         client = clnt_create(hostname, program, MOUNTVERS, "udp");
 106         if (client)
 107                 return client;
 108
 109         clnt_pcreateerror("clnt_create");
 110         exit(1);
 111 }
 112
 113 #else   /* HAVE_CLNT_CREATE */
 114
 115 /*
 116  *  Perform a non-blocking connect on the socket fd.
 117  *
 118  *  tout contains the timeout.  It will be modified to contain the time
 119  *  remaining (i.e. time provided - time elasped).
 120  *
 121  *  Returns zero on success; otherwise, -1 is returned and errno is set
 122  *  to reflect the nature of the error.
 123  */
 124 static int connect_nb(int fd, struct sockaddr_in *addr, struct timeval *tout)
 125 {
 126         int flags, ret;
 127         socklen_t len;
 128         fd_set rset;
 129
 130         flags = fcntl(fd, F_GETFL, 0);
 131         if (flags < 0)
 132                 return -1;
 133
 134         ret = fcntl(fd, F_SETFL, flags | O_NONBLOCK);
 135         if (ret < 0)
 136                 return -1;
 137
 138         /*
 139          * From here on subsequent sys calls could change errno so
 140          * we set ret = -errno to capture it in case we decide to
 141          * use it later.
 142          */
 143         len = sizeof(struct sockaddr);
 144         ret = connect(fd, (struct sockaddr *)addr, len);
 145         if (ret < 0 && errno != EINPROGRESS) {
 146                 ret = -1;
 147                 goto done;
 148         }
 149
 150         if (ret == 0)
 151                 goto done;
 152
 153         /* now wait */
 154         FD_ZERO(&rset);
 155         FD_SET(fd, &rset);
 156
 157         ret = select(fd + 1, NULL, &rset, NULL, tout);
 158         if (ret <= 0) {
 159                 if (ret == 0)
 160                         errno = ETIMEDOUT;
 161                 ret = -1;
 162                 goto done;
 163         }
 164
 165         if (FD_ISSET(fd, &rset)) {
 166                 int status;
 167
 168                 len = sizeof(ret);
 169                 status = getsockopt(fd, SOL_SOCKET, SO_ERROR, &ret, &len);
 170                 if (status < 0) {
 171                         ret = -1;
 172                         goto done;
 173                 }
 174
 175                 /* Oops - something wrong with connect */
 176                 if (ret != 0) {
 177                         errno = ret;
 178                         ret = -1;
 179                 }
 180         }
 181
 182 done:
 183         fcntl(fd, F_SETFL, flags);
 184         return ret;
 185 }
 186
 187 /*
 188  * Generate an RPC client handle connected to the mountd service
 189  * at @hostname, or die trying.
 190  *
 191  * Supports only AF_INET server addresses.
 192  */
 193 static CLIENT *nfs_get_mount_client(const char *hostname)
 194 {
 195         struct hostent *hp;
 196         struct sockaddr_in server_addr;
 197         struct timeval pertry_timeout;
 198         CLIENT *mclient = NULL;
 199         int ret, msock;
 200
 201         if (inet_aton(hostname, &server_addr.sin_addr)) {
 202                 server_addr.sin_family = AF_INET;
 203         }
 204         else {
 205                 if ((hp = gethostbyname(hostname)) == NULL) {
 206                         fprintf(stderr, "%s: can't get address for %s\n",
 207                                 program_name, hostname);
 208                         exit(1);
 209                 }
 210                 server_addr.sin_family = AF_INET;
 211                 memcpy(&server_addr.sin_addr, hp->h_addr, hp->h_length);
 212         }
 213
 214         msock = socket(PF_INET, SOCK_STREAM, IPPROTO_TCP);
 215         if (msock != -1) {
 216                 if (nfs_getport_ping((struct sockaddr *)&server_addr,
 217                                         sizeof(server_addr), MOUNTPROG,
 218                                         MOUNTVERS, IPPROTO_TCP)) {
 219                         ret = connect_nb(msock, &server_addr, 0);
 220                         if (ret == 0)
 221                                 mclient = clnttcp_create(&server_addr,
 222                                                 MOUNTPROG, MOUNTVERS, &msock,
 223                                                 0, 0);
 224                         else
 225                                 close(msock);
 226                 } else
 227                         close(msock);
 228         }
 229
 230         if (!mclient) {
 231                 if (nfs_getport_ping((struct sockaddr *)&server_addr,
 232                                         sizeof(server_addr), MOUNTPROG,
 233                                         MOUNTVERS, IPPROTO_UDP)) {
 234                         clnt_pcreateerror("showmount");
 235                         exit(1);
 236                 }
 237                 msock = RPC_ANYSOCK;
 238                 pertry_timeout.tv_sec = TIMEOUT_UDP;
 239                 pertry_timeout.tv_usec = 0;
 240                 if ((mclient = clntudp_create(&server_addr,
 241                     MOUNTPROG, MOUNTVERS, pertry_timeout, &msock)) == NULL) {
 242                         clnt_pcreateerror("mount clntudp_create");
 243                         exit(1);
 244                 }
 245         }
 246
 247         return mclient;
 248 }
 249
 250 #endif  /* HAVE_CLNT_CREATE */
 251
 252 int main(int argc, char **argv)
 253 {
 254         char hostname_buf[MAXHOSTLEN];
 255         char *hostname;
 256         enum clnt_stat clnt_stat;
 257         struct timeval total_timeout;
 258         int c;
 259         CLIENT *mclient;
 260         groups grouplist;
 261         exports exportlist, exl;
 262         mountlist dumplist;
 263         mountlist list;
 264         int i;
 265         int n;
 266         int maxlen;
 267         char **dumpv;
 268
 269         program_name = argv[0];
 270         while ((c = getopt_long(argc, argv, "adehv", longopts, NULL)) != EOF) {
 271                 switch (c) {
 272                 case 'a':
 273                         aflag = 1;
 274                         break;
 275                 case 'd':
 276                         dflag = 1;
 277                         break;
 278                 case 'e':
 279                         eflag = 1;
 280                         break;
 281                 case 'h':
 282                         usage(stdout, 0);
 283                         break;
 284                 case 'v':
 285                         printf("%s\n", version);
 286                         exit(0);
 287                 case 0:
 288                         break;
 289                 case '?':
 290                 default:
 291                         usage(stderr, 1);
 292                         break;
 293                 }
 294         }
 295         argc -= optind;
 296         argv += optind;
 297
 298         switch (aflag + dflag + eflag) {
 299         case 0:
 300                 hflag = 1;
 301                 break;
 302         case 1:
 303                 break;
 304         default:
 305                 fprintf(stderr, "%s: only one of -a, -d or -e is allowed\n",
 306                         program_name);
 307                 exit(1);
 308                 break;
 309         }
 310
 311         switch (argc) {
 312         case 0:
 313                 if (gethostname(hostname_buf, MAXHOSTLEN) < 0) {
 314                         perror("getting hostname");
 315                         exit(1);
 316                 }
 317                 hostname = hostname_buf;
 318                 break;
 319         case 1:
 320                 hostname = argv[0];
 321                 break;
 322         default:
 323                 fprintf(stderr, "%s: only one hostname is allowed\n",
 324                         program_name);
 325                 exit(1);
 326                 break;
 327         }
 328
 329         mclient = nfs_get_mount_client(hostname);
 330         mclient->cl_auth = authunix_create_default();
 331         total_timeout.tv_sec = TOTAL_TIMEOUT;
 332         total_timeout.tv_usec = 0;
 333
 334         if (eflag) {
 335                 memset(&exportlist, '\0', sizeof(exportlist));
 336
 337                 clnt_stat = clnt_call(mclient, MOUNTPROC_EXPORT,
 338                         (xdrproc_t) xdr_void, NULL,
 339                         (xdrproc_t) xdr_exports, (caddr_t) &exportlist,
 340                         total_timeout);
 341                 if (clnt_stat != RPC_SUCCESS) {
 342                         clnt_perror(mclient, "rpc mount export");
 343                         clnt_destroy(mclient);
 344                         exit(1);
 345                 }
 346                 if (headers)
 347                         printf("Export list for %s:\n", hostname);
 348                 maxlen = 0;
 349                 for (exl = exportlist; exl; exl = exl->ex_next) {
 350                         if ((n = strlen(exl->ex_dir)) > maxlen)
 351                                 maxlen = n;
 352                 }
 353                 while (exportlist) {
 354                         printf("%-*s ", maxlen, exportlist->ex_dir);
 355                         grouplist = exportlist->ex_groups;
 356                         if (grouplist)
 357                                 while (grouplist) {
 358                                         printf("%s%s", grouplist->gr_name,
 359                                                 grouplist->gr_next ? "," : "");
 360                                         grouplist = grouplist->gr_next;
 361                                 }
 362                         else
 363                                 printf("(everyone)");
 364                         printf("\n");
 365                         exportlist = exportlist->ex_next;
 366                 }
 367                 clnt_destroy(mclient);
 368                 exit(0);
 369         }
 370
 371         memset(&dumplist, '\0', sizeof(dumplist));
 372         clnt_stat = clnt_call(mclient, MOUNTPROC_DUMP,
 373                 (xdrproc_t) xdr_void, NULL,
 374                 (xdrproc_t) xdr_mountlist, (caddr_t) &dumplist,
 375                 total_timeout);
 376         if (clnt_stat != RPC_SUCCESS) {
 377                 clnt_perror(mclient, "rpc mount dump");
 378                 clnt_destroy(mclient);
 379                 exit(1);
 380         }
 381         clnt_destroy(mclient);
 382
 383         n = 0;
 384         for (list = dumplist; list; list = list->ml_next)
 385                 n++;
 386         dumpv = (char **) calloc(n, sizeof (char *));
 387         if (n && !dumpv) {
 388                 fprintf(stderr, "%s: out of memory\n", program_name);
 389                 exit(1);
 390         }
 391         i = 0;
 392
 393         if (hflag) {
 394                 if (headers)
 395                         printf("Hosts on %s:\n", hostname);
 396                 while (dumplist) {
 397                         dumpv[i++] = dumplist->ml_hostname;
 398                         dumplist = dumplist->ml_next;
 399                 }
 400         }
 401         else if (aflag) {
 402                 if (headers)
 403                         printf("All mount points on %s:\n", hostname);
 404                 while (dumplist) {
 405                         char *t;
 406
 407                         t=malloc(strlen(dumplist->ml_hostname)+strlen(dumplist->ml_directory)+2);
 408                         if (!t)
 409                         {
 410                                 fprintf(stderr, "%s: out of memory\n", program_name);
 411                                 exit(1);
 412                         }
 413                         sprintf(t, "%s:%s", dumplist->ml_hostname, dumplist->ml_directory);
 414                         dumpv[i++] = t;
 415                         dumplist = dumplist->ml_next;
 416                 }
 417         }
 418         else if (dflag) {
 419                 if (headers)
 420                         printf("Directories on %s:\n", hostname);
 421                 while (dumplist) {
 422                         dumpv[i++] = dumplist->ml_directory;
 423                         dumplist = dumplist->ml_next;
 424                 }
 425         }
 426
 427         qsort(dumpv, n, sizeof (char *), dump_cmp);
 428
 429         for (i = 0; i < n; i++) {
 430                 if (i == 0 || strcmp(dumpv[i], dumpv[i - 1]) != 0)
 431                         printf("%s\n", dumpv[i]);
 432         }
 433         exit(0);
 434 }
 435