kinit/lnusertemp.c

   1 /*
   2   This file is part of the KDE libraries
   3   Copyright (c) 2000 Waldo Bastian <bastian@kde.org>
   4
   5   This library is free software; you can redistribute it and/or
   6   modify it under the terms of the GNU Library General Public
   7   License version 2 as published by the Free Software Foundation.
   8
   9   This library is distributed in the hope that it will be useful,
  10   but WITHOUT ANY WARRANTY; without even the implied warranty of
  11   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12   Library General Public License for more details.
  13
  14   You should have received a copy of the GNU Library General Public License
  15   along with this library; see the file COPYING.LIB.  If not, write to
  16   the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
  17   Boston, MA 02110-1301, USA.
  18 */
  19
  20 #include "config.h"
  21 #include <config-kstandarddirs.h>
  22
  23 #include <sys/types.h>
  24 #include <sys/param.h>
  25 #include <sys/socket.h>
  26 #include <sys/stat.h>
  27 #include <sys/un.h>
  28
  29 #include <errno.h>
  30 #include <string.h>
  31 #include <stdio.h>
  32 #include <stdlib.h>
  33 #include <unistd.h>
  34 #include <pwd.h>
  35 #ifdef HAVE_LIMITS_H
  36 #include <limits.h>
  37 #endif
  38
  39 int check_tmp_dir(const char *tmp_dir, int check_ownership);
  40 int create_link(const char *file, const char *tmp_dir);
  41 int build_link(const char* tmp, const char *tmp_prefix, const char *kde_prefix);
  42
  43 /* checks that tmp_dir exists, otherwise creates it
  44  * @param check_ownership: if 1, also check that user owns the dir
  45  * returns 0 on success
  46  */
  47 int check_tmp_dir(const char *tmp_dir, int check_ownership)
  48 {
  49   /* reserve some space for an error string + a path name */
  50   char errorstring[PATH_MAX+1024];
  51   int result;
  52   struct stat stat_buf;
  53   result = lstat(tmp_dir, &stat_buf);
  54   if ((result == -1) && (errno == ENOENT))
  55   {
  56 #ifdef _WIN32
  57     result = mkdir(tmp_dir);
  58 #else
  59     result = mkdir(tmp_dir, 0700);
  60 #endif
  61     if (result == -1)
  62     {
  63        snprintf(errorstring, sizeof(errorstring), "Error: cannot create directory \"%s\"", tmp_dir);
  64        perror(errorstring);
  65        return 1;
  66     }
  67     result = stat(tmp_dir, &stat_buf);
  68   }
  69   if ((result == -1) || ( !S_ISDIR(stat_buf.st_mode) && !S_ISLNK(stat_buf.st_mode) ))
  70   {
  71      fprintf(stderr, "Error: \"%s\" is not a directory.\n", tmp_dir);
  72      return 1;
  73   }
  74
  75   if (check_ownership && stat_buf.st_uid != getuid())
  76   {
  77      fprintf(stderr, "Error: \"%s\" is owned by uid %d instead of uid %d.\n", tmp_dir, stat_buf.st_uid, getuid());
  78      return 1;
  79   }
  80   return 0;
  81 }
  82
  83 int create_link(const char *file, const char *tmp_dir)
  84 {
  85   int result;
  86   result = check_tmp_dir(tmp_dir, 1);
  87   if (result)
  88   {
  89      return result;
  90   }
  91   result = symlink(tmp_dir, file);
  92   if (result == -1)
  93   {
  94      fprintf(stderr, "Error: Can not create link from \"%s\" to \"%s\"\n", file, tmp_dir);
  95      return 1;
  96   }
  97 #ifndef NDEBUG
  98   fprintf(stderr,"Created link from \"%s\" to \"%s\"\n", file, tmp_dir);
  99 #endif
 100   return 0;
 101 }
 102
 103
 104 int build_link(const char* tmp, const char *tmp_prefix, const char *kde_prefix)
 105 {
 106   struct passwd *pw_ent;
 107   char kde_tmp_dir[PATH_MAX+1];
 108   char user_tmp_dir[PATH_MAX+1];
 109   char tmp_buf[PATH_MAX+1];
 110   int uid = getuid();
 111   const char *home_dir = getenv("HOME");
 112   const char *kde_home = uid ? getenv("KDEHOME") : getenv("KDEROOTHOME");
 113   int result;
 114   struct stat stat_buf;
 115
 116   kde_tmp_dir[0] = 0;
 117
 118   pw_ent = getpwuid(uid);
 119   if (!pw_ent)
 120   {
 121      fprintf(stderr, "Error: Can not find password entry for uid %d.\n", getuid());
 122      return 1;
 123   }
 124
 125   strncpy(user_tmp_dir, tmp_prefix, PATH_MAX);
 126   user_tmp_dir[ PATH_MAX ] = '\0';
 127   strncat(user_tmp_dir, pw_ent->pw_name, PATH_MAX - strlen(tmp_prefix));
 128
 129   if (!kde_home || !kde_home[0])
 130   {
 131      kde_home = "~/" KDE_DEFAULT_HOME "/";
 132   }
 133
 134   if (kde_home[0] == '~')
 135   {
 136      if (uid == 0)
 137      {
 138         home_dir = pw_ent->pw_dir ? pw_ent->pw_dir : "/root";
 139      }
 140      if (!home_dir || !home_dir[0])
 141      {
 142         fprintf(stderr, "Aborting. $HOME not set!\n");
 143         return 1;
 144      }
 145      if (strlen(home_dir) > (PATH_MAX-100))
 146      {
 147         fprintf(stderr, "Aborting. Home directory path too long!\n");
 148         return 1;
 149      }
 150      kde_home++;
 151      strncpy(kde_tmp_dir, home_dir, PATH_MAX);
 152      kde_tmp_dir[ PATH_MAX ] = '\0';
 153   }
 154   strncat(kde_tmp_dir, kde_home, PATH_MAX - strlen(kde_tmp_dir));
 155
 156   /** Strip trailing '/' **/
 157   if ( kde_tmp_dir[strlen(kde_tmp_dir)-1] == '/')
 158      kde_tmp_dir[strlen(kde_tmp_dir)-1] = 0;
 159
 160   result = stat(kde_tmp_dir, &stat_buf);
 161   if ((result == -1) && (errno == ENOENT))
 162   {
 163 #ifdef _WIN32
 164      result = mkdir(kde_tmp_dir);
 165 #else
 166      result = mkdir(kde_tmp_dir, 0700);
 167 #endif
 168   }
 169   if (result == -1)
 170   {
 171      perror("mkdir failed: ");
 172      return 1;
 173   }
 174
 175   strncat(kde_tmp_dir, kde_prefix, PATH_MAX - strlen(kde_tmp_dir));
 176   if (gethostname(kde_tmp_dir+strlen(kde_tmp_dir), PATH_MAX - strlen(kde_tmp_dir) - 1) != 0)
 177   {
 178      perror("Aborting. Could not determine hostname: ");
 179      exit(255);
 180   }
 181   kde_tmp_dir[sizeof(kde_tmp_dir)-1] = '\0';
 182
 183   result = lstat(kde_tmp_dir, &stat_buf);
 184   if ((result == 0) && (S_ISDIR(stat_buf.st_mode)))
 185   {
 186      /* $KDEHOME/tmp is a normal directory. Do nothing. */
 187 #ifndef NDEBUG
 188      fprintf(stderr,"Directory \"%s\" already exists.\n", kde_tmp_dir);
 189 #endif
 190      return 0;
 191   }
 192   if ((result == -1) && (errno == ENOENT))
 193   {
 194 #ifndef NDEBUG
 195      fprintf(stderr,"Creating link %s.\n", kde_tmp_dir);
 196 #endif
 197      result = create_link(kde_tmp_dir, user_tmp_dir);
 198      if (result == 0) return 0; /* Success */
 199      unlink(kde_tmp_dir);
 200      strncat(user_tmp_dir, "XXXXXX", PATH_MAX - strlen(user_tmp_dir));
 201 #if 0
 202      mktemp(user_tmp_dir); /* We want a directory, not a file, so using mkstemp makes no sense and is wrong */
 203 #else
 204      if (mkdtemp(user_tmp_dir)==0) return 1; /*JOWENN: isn't that the better solution ?? */
 205 #endif
 206      return create_link(kde_tmp_dir, user_tmp_dir);
 207   }
 208   if ((result == -1) || (!S_ISLNK(stat_buf.st_mode)))
 209   {
 210      fprintf(stderr, "Error: \"%s\" is not a link or a directory.\n", kde_tmp_dir);
 211      return 1;
 212   }
 213   /* kde_tmp_dir is a link. Check whether it points to a valid directory. */
 214   result = readlink(kde_tmp_dir, tmp_buf, PATH_MAX);
 215   if (result == -1)
 216   {
 217      fprintf(stderr, "Error: \"%s\" could not be read.\n", kde_tmp_dir);
 218      return 1;
 219   }
 220   tmp_buf[result] = '\0';
 221 #ifndef NDEBUG
 222   fprintf(stderr,"Link points to \"%s\"\n", tmp_buf);
 223 #endif
 224   if (strncmp(tmp_buf, user_tmp_dir, strlen(user_tmp_dir)) != 0)
 225   {
 226      fprintf(stderr, "Error: \"%s\" points to \"%s\" instead of \"%s\".\n", kde_tmp_dir, tmp_buf, user_tmp_dir);
 227      unlink(kde_tmp_dir);
 228 #ifndef NDEBUG
 229      fprintf(stderr, "Creating link %s.\n", kde_tmp_dir);
 230 #endif
 231      result = create_link(kde_tmp_dir, user_tmp_dir);
 232      if (result == 0) return 0; /* Success */
 233      unlink(kde_tmp_dir);
 234      strncat(user_tmp_dir, "XXXXXX", PATH_MAX - strlen(user_tmp_dir));
 235 #if 0
 236      mktemp(user_tmp_dir); /* We want a directory, not a file, so using mkstemp makes no sense and is wrong */
 237 #else
 238      if (mkdtemp(user_tmp_dir)==0) return 1; /*JOWENN: isn't that the better solution ?? */
 239 #endif
 240      return create_link(kde_tmp_dir, user_tmp_dir);
 241   }
 242   result = check_tmp_dir(tmp, 0);
 243   if (result != 0) return result; /* Failure to create parent dir */
 244   result = check_tmp_dir(tmp_buf, 1);
 245   if (result == 0) return 0; /* Success */
 246   unlink(kde_tmp_dir);
 247   strncat(user_tmp_dir, "XXXXXX", PATH_MAX - strlen(user_tmp_dir));
 248 #if 0
 249   mktemp(user_tmp_dir); /* We want a directory, not a file, so using mkstemp makes no sense and is wrong */
 250 #else
 251      if (mkdtemp(user_tmp_dir)==0) return 1; /*JOWENN: isn't that the better solution ?? */
 252 #endif
 253   return create_link(kde_tmp_dir, user_tmp_dir);
 254 }
 255
 256 int main(int argc, char **argv)
 257 {
 258   const char *tmp = 0;
 259   char *tmp_prefix = 0;
 260   const char *kde_prefix = 0;
 261   int res = 0;
 262
 263   if ((argc != 2) ||
 264       ((strcmp(argv[1], "tmp")!=0) &&
 265        (strcmp(argv[1], "socket")!=0) &&
 266        (strcmp(argv[1], "cache")!=0)))
 267   {
 268      fprintf(stderr, "Usage: lnusertemp tmp|socket|cache\n");
 269      return 1;
 270   }
 271
 272   tmp = getenv("KDETMP");
 273   if (!tmp || !tmp[0])
 274     tmp = getenv("TMPDIR");
 275   if (!tmp || !tmp[0])
 276     tmp = "/tmp";
 277
 278   if (strcmp(argv[1], "tmp") == 0)
 279   {
 280     tmp_prefix = (char *)malloc(strlen(tmp)+strlen("/kde-")+1);
 281     strcpy(tmp_prefix, tmp);
 282     strcat(tmp_prefix, "/kde-");
 283
 284     kde_prefix = "/tmp-";
 285   }
 286   else if (strcmp(argv[1], "socket") == 0)
 287   {
 288     tmp_prefix = (char *)malloc(strlen(tmp)+strlen("/ksocket-")+1);
 289     strcpy(tmp_prefix, tmp );
 290     strcat(tmp_prefix, "/ksocket-" );
 291
 292     kde_prefix = "/socket-";
 293   }
 294   else if (strcmp(argv[1], "cache") == 0)
 295   {
 296     tmp = getenv("KDEVARTMP");
 297     if (!tmp || !tmp[0])
 298       tmp = "/var/tmp";
 299
 300     tmp_prefix = (char *)malloc(strlen(tmp)+strlen("/kdecache-")+1);
 301     strcpy(tmp_prefix, tmp );
 302     strcat(tmp_prefix, "/kdecache-" );
 303
 304     kde_prefix = "/cache-";
 305   }
 306
 307   res = build_link(tmp, tmp_prefix, kde_prefix);
 308
 309   free(tmp_prefix);
 310
 311   return res;
 312 }