usr.bin/pathchk/pathchk.c

   1 /*-
   2  * Copyright (c) 2002 Tim J. Robbins.
   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
  27 /*
  28  * pathchk -- check pathnames
  29  *
  30  * Check whether files could be created with the names specified on the
  31  * command line. If -p is specified, check whether the pathname is portable
  32  * to all POSIX systems.
  33  */
  34
  35 #include <sys/cdefs.h>
  36 __FBSDID("$FreeBSD$");
  37
  38 #include <sys/types.h>
  39 #include <sys/stat.h>
  40
  41 #include <err.h>
  42 #include <errno.h>
  43 #include <limits.h>
  44 #include <stdio.h>
  45 #include <stdlib.h>
  46 #include <string.h>
  47 #include <unistd.h>
  48
  49 static int       check(const char *);
  50 static int       portable(const char *);
  51 static void      usage(void);
  52
  53 static int       pflag;                 /* Perform portability checks */
  54 static int       Pflag;                 /* Check for empty paths, leading '-' */
  55
  56 int
  57 main(int argc, char *argv[])
  58 {
  59         int ch, rval;
  60         const char *arg;
  61
  62         while ((ch = getopt(argc, argv, "pP")) > 0) {
  63                 switch (ch) {
  64                 case 'p':
  65                         pflag = 1;
  66                         break;
  67                 case 'P':
  68                         Pflag = 1;
  69                         break;
  70                 default:
  71                         usage();
  72                         /*NOTREACHED*/
  73                 }
  74         }
  75         argc -= optind;
  76         argv += optind;
  77
  78         if (argc == 0)
  79                 usage();
  80
  81         rval = 0;
  82         while ((arg = *argv++) != NULL)
  83                 rval |= check(arg);
  84
  85         exit(rval);
  86 }
  87
  88 static void
  89 usage(void)
  90 {
  91
  92         fprintf(stderr, "usage: pathchk [-Pp] pathname ...\n");
  93         exit(1);
  94 }
  95
  96 static int
  97 check(const char *path)
  98 {
  99         struct stat sb;
 100         long complen, namemax, pathmax, svnamemax;
 101         int last;
 102         char *end, *p, *pathd;
 103
 104         if ((pathd = strdup(path)) == NULL)
 105                 err(1, "strdup");
 106
 107         p = pathd;
 108
 109         if (Pflag && *p == '\0') {
 110                 warnx("%s: empty pathname", path);
 111                 goto bad;
 112         }
 113         if ((Pflag || pflag) && (*p == '-' || strstr(p, "/-") != NULL)) {
 114                 warnx("%s: contains a component starting with '-'", path);
 115                 goto bad;
 116         }
 117
 118         if (!pflag) {
 119                 errno = 0;
 120                 namemax = pathconf(*p == '/' ? "/" : ".", _PC_NAME_MAX);
 121                 if (namemax == -1 && errno != 0)
 122                         namemax = NAME_MAX;
 123         } else
 124                 namemax = _POSIX_NAME_MAX;
 125
 126         for (;;) {
 127                 p += strspn(p, "/");
 128                 complen = (long)strcspn(p, "/");
 129                 end = p + complen;
 130                 last = *end == '\0';
 131                 *end = '\0';
 132
 133                 if (namemax != -1 && complen > namemax) {
 134                         warnx("%s: %s: component too long (limit %ld)", path,
 135                             p, namemax);
 136                         goto bad;
 137                 }
 138
 139                 if (!pflag && stat(pathd, &sb) == -1 && errno != ENOENT) {
 140                         warn("%s: %.*s", path, (int)(strlen(pathd) -
 141                             complen - 1), pathd);
 142                         goto bad;
 143                 }
 144
 145                 if (pflag && !portable(p)) {
 146                         warnx("%s: %s: component contains non-portable "
 147                             "character", path, p);
 148                         goto bad;
 149                 }
 150
 151                 if (last)
 152                         break;
 153
 154                 if (!pflag) {
 155                         errno = 0;
 156                         svnamemax = namemax;
 157                         namemax = pathconf(pathd, _PC_NAME_MAX);
 158                         if (namemax == -1 && errno != 0)
 159                                 namemax = svnamemax;
 160                 }
 161
 162                 *end = '/';
 163                 p = end + 1;
 164         }
 165
 166         if (!pflag) {
 167                 errno = 0;
 168                 pathmax = pathconf(path, _PC_PATH_MAX);
 169                 if (pathmax == -1 && errno != 0)
 170                         pathmax = PATH_MAX;
 171         } else
 172                 pathmax = _POSIX_PATH_MAX;
 173         if (pathmax != -1 && strlen(path) >= (size_t)pathmax) {
 174                 warnx("%s: path too long (limit %ld)", path, pathmax - 1);
 175                 goto bad;
 176         }
 177
 178         free(pathd);
 179         return (0);
 180
 181 bad:    free(pathd);
 182         return (1);
 183 }
 184
 185 /*
 186  * Check whether a path component contains only portable characters.
 187  */
 188 static int
 189 portable(const char *path)
 190 {
 191         static const char charset[] =
 192             "abcdefghijklmnopqrstuvwxyz"
 193             "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
 194             "0123456789._-";
 195         long s;
 196
 197         s = strspn(path, charset);
 198         if (path[s] != '\0')
 199                 return (0);
 200
 201         return (1);
 202 }