usr.sbin/rpc.umntall/mounttab.c

   1 /*
   2  * Copyright (c) 1999 Martin Blapp
   3  * 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  *
  14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  24  * SUCH DAMAGE.
  25  *
  26  * $FreeBSD: src/usr.sbin/rpc.umntall/mounttab.c,v 1.2.2.1 2001/12/13 01:27:20 iedowse Exp $
  27  * $DragonFly: src/usr.sbin/rpc.umntall/mounttab.c,v 1.4 2008/11/12 21:44:59 swildner Exp $
  28  */
  29
  30 #include <sys/syslog.h>
  31
  32 #include <rpc/rpc.h>
  33 #include <nfs/rpcv2.h>
  34
  35 #include <err.h>
  36 #include <errno.h>
  37 #include <limits.h>
  38 #include <stdio.h>
  39 #include <stdlib.h>
  40 #include <string.h>
  41 #include <unistd.h>
  42
  43 #include "mounttab.h"
  44
  45 struct mtablist *mtabhead;
  46
  47 static void badline(const char *field, const char *bad);
  48
  49 /*
  50  * Add an entry to PATH_MOUNTTAB for each mounted NFS filesystem,
  51  * so the client can notify the NFS server even after reboot.
  52  */
  53 int
  54 add_mtab(char *hostp, char *dirp) {
  55         FILE *mtabfile;
  56
  57         if ((mtabfile = fopen(PATH_MOUNTTAB, "a")) == NULL)
  58                 return (0);
  59         else {
  60                 fprintf(mtabfile, "%ld\t%s\t%s\n",
  61                     (long)time(NULL), hostp, dirp);
  62                 fclose(mtabfile);
  63                 return (1);
  64         }
  65 }
  66
  67 /*
  68  * Read mounttab line for line and return struct mtablist.
  69  */
  70 int
  71 read_mtab(void) {
  72         struct mtablist **mtabpp, *mtabp;
  73         char *hostp, *dirp, *cp;
  74         char str[STRSIZ];
  75         char *timep, *endp;
  76         time_t mnt_time;
  77         u_long ultmp;
  78         FILE *mtabfile;
  79
  80         if ((mtabfile = fopen(PATH_MOUNTTAB, "r")) == NULL) {
  81                 if (errno == ENOENT)
  82                         return (0);
  83                 else {
  84                         syslog(LOG_ERR, "can't open %s", PATH_MOUNTTAB);
  85                         return (0);
  86                 }
  87         }
  88         mnt_time = 0;
  89         mtabpp = &mtabhead;
  90         while (fgets(str, STRSIZ, mtabfile) != NULL) {
  91                 cp = str;
  92                 errno = 0;
  93                 if (*cp == '#' || *cp == ' ' || *cp == '\n')
  94                         continue;
  95                 timep = strsep(&cp, " \t\n");
  96                 if (timep == NULL || *timep == '\0') {
  97                         badline("time", timep);
  98                         continue;
  99                 }
 100                 hostp = strsep(&cp, " \t\n");
 101                 if (hostp == NULL || *hostp == '\0') {
 102                         badline("host", hostp);
 103                         continue;
 104                 }
 105                 dirp = strsep(&cp, " \t\n");
 106                 if (dirp == NULL || *dirp == '\0') {
 107                         badline("dir", dirp);
 108                         continue;
 109                 }
 110                 ultmp = strtoul(timep, &endp, 10);
 111                 if (ultmp == ULONG_MAX || *endp != '\0') {
 112                         badline("time", timep);
 113                         continue;
 114                 }
 115                 mnt_time = ultmp;
 116                 if ((mtabp = malloc(sizeof (struct mtablist))) == NULL) {
 117                         syslog(LOG_ERR, "malloc");
 118                         fclose(mtabfile);
 119                         return (0);
 120                 }
 121                 mtabp->mtab_time = mnt_time;
 122                 memmove(mtabp->mtab_host, hostp, RPCMNT_NAMELEN);
 123                 mtabp->mtab_host[RPCMNT_NAMELEN - 1] = '\0';
 124                 memmove(mtabp->mtab_dirp, dirp, RPCMNT_PATHLEN);
 125                 mtabp->mtab_dirp[RPCMNT_PATHLEN - 1] = '\0';
 126                 mtabp->mtab_next = NULL;
 127                 *mtabpp = mtabp;
 128                 mtabpp = &mtabp->mtab_next;
 129         }
 130         fclose(mtabfile);
 131         return (1);
 132 }
 133
 134 /*
 135  * Rewrite PATH_MOUNTTAB from scratch and skip bad entries.
 136  * Unlink PATH_MOUNTAB if no entry is left.
 137  */
 138 int
 139 write_mtab(int verbose) {
 140         struct mtablist *mtabp, *mp;
 141         FILE *mtabfile;
 142         int line;
 143
 144         if ((mtabfile = fopen(PATH_MOUNTTAB, "w")) == NULL) {
 145                 syslog(LOG_ERR, "can't write to %s", PATH_MOUNTTAB);
 146                         return (0);
 147         }
 148         line = 0;
 149         for (mtabp = mtabhead; mtabp != NULL; mtabp = mtabp->mtab_next) {
 150                 if (mtabp->mtab_host[0] == '\0')
 151                         continue;
 152                 /* Skip if a later (hence more recent) entry is identical. */
 153                 for (mp = mtabp->mtab_next; mp != NULL; mp = mp->mtab_next)
 154                         if (strcmp(mtabp->mtab_host, mp->mtab_host) == 0 &&
 155                             strcmp(mtabp->mtab_dirp, mp->mtab_dirp) == 0)
 156                                 break;
 157                 if (mp != NULL)
 158                         continue;
 159
 160                 fprintf(mtabfile, "%ld\t%s\t%s\n",
 161                     (long)mtabp->mtab_time, mtabp->mtab_host,
 162                     mtabp->mtab_dirp);
 163                 if (verbose)
 164                         warnx("write mounttab entry %s:%s",
 165                             mtabp->mtab_host, mtabp->mtab_dirp);
 166                 line++;
 167         }
 168         fclose(mtabfile);
 169         if (line == 0) {
 170                 if (unlink(PATH_MOUNTTAB) == -1) {
 171                         syslog(LOG_ERR, "can't remove %s", PATH_MOUNTTAB);
 172                         return (0);
 173                 }
 174         }
 175         return (1);
 176 }
 177
 178 /*
 179  * Mark the entries as clean where RPC calls have been done successfully.
 180  */
 181 void
 182 clean_mtab(char *hostp, char *dirp, int verbose) {
 183         struct mtablist *mtabp;
 184         char *host;
 185
 186         /* Copy hostp in case it points to an entry that we are zeroing out. */
 187         host = strdup(hostp);
 188         for (mtabp = mtabhead; mtabp != NULL; mtabp = mtabp->mtab_next) {
 189                 if (strcmp(mtabp->mtab_host, host) != 0)
 190                         continue;
 191                 if (dirp != NULL && strcmp(mtabp->mtab_dirp, dirp) != 0)
 192                         continue;
 193
 194                 if (verbose)
 195                         warnx("delete mounttab entry%s %s:%s",
 196                             (dirp == NULL) ? " by host" : "",
 197                             mtabp->mtab_host, mtabp->mtab_dirp);
 198                 bzero(mtabp->mtab_host, RPCMNT_NAMELEN);
 199         }
 200         free(host);
 201 }
 202
 203 /*
 204  * Free struct mtablist mtab.
 205  */
 206 void
 207 free_mtab(void) {
 208         struct mtablist *mtabp;
 209
 210         while ((mtabp = mtabhead) != NULL) {
 211                 mtabhead = mtabhead->mtab_next;
 212                 free(mtabp);
 213         }
 214 }
 215
 216 /*
 217  * Print bad lines to syslog.
 218  */
 219 static void
 220 badline(const char *field, const char *bad) {
 221         syslog(LOG_ERR, "bad mounttab %s field '%s'", field,
 222             (bad == NULL) ? "<null>" : bad);
 223 }