/* pathchk -- check whether pathnames are valid or portable Copyright (C) 91, 92, 93, 1994 Free Software Foundation, Inc. This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ /* Usage: pathchk [-p] [--portability] path... For each PATH, print a message if any of these conditions are false: * all existing leading directories in PATH have search (execute) permission * strlen (PATH) <= PATH_MAX * strlen (each_directory_in_PATH) <= NAME_MAX Exit status: 0 All PATH names passed all of the tests. 1 An error occurred. Options: -p, --portability Instead of performing length checks on the underlying filesystem, test the length of the pathname and its components against the POSIX.1 minimum limits for portability, _POSIX_NAME_MAX and _POSIX_PATH_MAX in 2.9.2. Also check that the pathname contains no character not in the portable filename character set. David MacKenzie and Jim Meyering */ #ifdef HAVE_CONFIG_H #include #endif #include #include #include #include "version.h" #include "system.h" #include "safe-stat.h" #ifdef _POSIX_VERSION #include #ifndef PATH_MAX #define PATH_MAX_FOR(p) pathconf ((p), _PC_PATH_MAX) #endif /* not PATH_MAX */ #ifndef NAME_MAX #define NAME_MAX_FOR(p) pathconf ((p), _PC_NAME_MAX); #endif /* not NAME_MAX */ #else /* not _POSIX_VERSION */ #include #ifndef PATH_MAX #ifdef MAXPATHLEN #define PATH_MAX MAXPATHLEN #else /* not MAXPATHLEN */ #define PATH_MAX _POSIX_PATH_MAX #endif /* not MAXPATHLEN */ #endif /* not PATH_MAX */ #ifndef NAME_MAX #ifdef MAXNAMLEN #define NAME_MAX MAXNAMLEN #else /* not MAXNAMLEN */ #define NAME_MAX _POSIX_NAME_MAX #endif /* not MAXNAMLEN */ #endif /* not NAME_MAX */ #endif /* not _POSIX_VERSION */ #ifndef _POSIX_PATH_MAX #define _POSIX_PATH_MAX 255 #endif #ifndef _POSIX_NAME_MAX #define _POSIX_NAME_MAX 14 #endif #ifndef PATH_MAX_FOR #define PATH_MAX_FOR(p) PATH_MAX #endif #ifndef NAME_MAX_FOR #define NAME_MAX_FOR(p) NAME_MAX #endif char *xstrdup (); void error (); static int validate_path (); static void usage (); /* The name this program was run with. */ char *program_name; /* If non-zero, display usage information and exit. */ static int show_help; /* If non-zero, print the version on standard output and exit. */ static int show_version; static struct option const longopts[] = { {"help", no_argument, &show_help, 1}, {"portability", no_argument, NULL, 'p'}, {"version", no_argument, &show_version, 1}, {NULL, 0, NULL, 0} }; void main (argc, argv) int argc; char **argv; { int exit_status = 0; int check_portability = 0; int optc; program_name = argv[0]; while ((optc = getopt_long (argc, argv, "p", longopts, (int *) 0)) != EOF) { switch (optc) { case 0: break; case 'p': check_portability = 1; break; default: usage (1); } } if (show_version) { printf ("pathchk - %s\n", version_string); exit (0); } if (show_help) usage (0); if (optind == argc) usage (1); for (; optind < argc; ++optind) exit_status |= validate_path (argv[optind], check_portability); exit (exit_status); } /* Each element is nonzero if the corresponding ASCII character is in the POSIX portable character set, and zero if it is not. In addition, the entry for `/' is nonzero to simplify checking. */ static char const portable_chars[256] = { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* 0-15 */ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* 16-31 */ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, /* 32-47 */ 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, /* 48-63 */ 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, /* 64-79 */ 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 1, /* 80-95 */ 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, /* 96-111 */ 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, /* 112-127 */ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 }; /* If PATH contains only portable characters, return 1, else 0. */ static int portable_chars_only (path) const char *path; { const char *p; for (p = path; *p; ++p) if (portable_chars[(const unsigned char) *p] == 0) { error (0, 0, "path `%s' contains nonportable character `%c'", path, *p); return 0; } return 1; } /* Return 1 if PATH is a usable leading directory, 0 if not, 2 if it doesn't exist. */ static int dir_ok (path) const char *path; { struct stat stats; if (SAFE_STAT (path, &stats)) return 2; if (!S_ISDIR (stats.st_mode)) { error (0, 0, "`%s' is not a directory", path); return 0; } /* Use access to test for search permission because testing permission bits of st_mode can lose with new access control mechanisms. Of course, access loses if you're running setuid. */ if (access (path, X_OK) != 0) { if (errno == EACCES) error (0, 0, "directory `%s' is not searchable", path); else error (0, errno, "%s", path); return 0; } return 1; } /* Make sure that strlen (PATH) <= PATH_MAX && strlen (each-existing-directory-in-PATH) <= NAME_MAX If PORTABILITY is nonzero, compare against _POSIX_PATH_MAX and _POSIX_NAME_MAX instead, and make sure that PATH contains no characters not in the POSIX portable filename character set, which consists of A-Z, a-z, 0-9, ., _, -. Make sure that all leading directories along PATH that exist have `x' permission. Return 0 if all of these tests are successful, 1 if any fail. */ static int validate_path (path, portability) char *path; int portability; { int path_max; int last_elem; /* Nonzero if checking last element of path. */ int exists; /* 2 if the path element exists. */ char *slash; char *parent; /* Last existing leading directory so far. */ if (portability && !portable_chars_only (path)) return 1; if (*path == '\0') return 0; #ifdef lint /* Suppress `used before initialized' warning. */ exists = 0; #endif /* Figure out the parent of the first element in PATH. */ parent = xstrdup (*path == '/' ? "/" : "."); slash = path; last_elem = 0; while (1) { int name_max; int length; /* Length of partial path being checked. */ char *start; /* Start of path element being checked. */ /* Find the end of this element of the path. Then chop off the rest of the path after this element. */ while (*slash == '/') slash++; start = slash; slash = index (slash, '/'); if (slash != NULL) *slash = '\0'; else { last_elem = 1; slash = index (start, '\0'); } if (!last_elem) { exists = dir_ok (path); if (dir_ok == 0) { free (parent); return 1; } } length = slash - start; /* Since we know that `parent' is a directory, it's ok to call pathconf with it as the argument. (If `parent' isn't a directory or doesn't exist, the behavior of pathconf is undefined.) But if `parent' is a directory and is on a remote file system, it's likely that pathconf can't give us a reasonable value and will return -1. (NFS and tempfs are not POSIX . . .) In that case, we have no choice but to assume the pessimal POSIX minimums. */ name_max = portability ? _POSIX_NAME_MAX : NAME_MAX_FOR (parent); if (name_max < 0) name_max = _POSIX_NAME_MAX; if (length > name_max) { error (0, 0, "name `%s' has length %d; exceeds limit of %d", start, length, name_max); free (parent); return 1; } if (last_elem) break; if (exists == 1) { free (parent); parent = xstrdup (path); } *slash++ = '/'; } /* `parent' is now the last existing leading directory in the whole path, so it's ok to call pathconf with it as the argument. */ path_max = portability ? _POSIX_PATH_MAX : PATH_MAX_FOR (parent); if (path_max < 0) path_max = _POSIX_PATH_MAX; free (parent); if (strlen (path) > path_max) { error (0, 0, "path `%s' has length %d; exceeds limit of %d", path, strlen (path), path_max); return 1; } return 0; } static void usage (status) int status; { if (status != 0) fprintf (stderr, "Try `%s --help' for more information.\n", program_name); else { printf ("Usage: %s [OPTION]... PATH...\n", program_name); printf ("\ \n\ -p, --portability check for all POSIX systems, not only this one\n\ --help display this help and exit\n\ --version output version information and exit\n\ "); } exit (status); }