1 /* $OpenBSD: access.c,v 1.5 2010/01/12 23:22:06 nicm Exp $ */ 2 3 /**************************************************************************** 4 * Copyright (c) 1998-2006,2007 Free Software Foundation, Inc. * 5 * * 6 * Permission is hereby granted, free of charge, to any person obtaining a * 7 * copy of this software and associated documentation files (the * 8 * "Software"), to deal in the Software without restriction, including * 9 * without limitation the rights to use, copy, modify, merge, publish, * 10 * distribute, distribute with modifications, sublicense, and/or sell * 11 * copies of the Software, and to permit persons to whom the Software is * 12 * furnished to do so, subject to the following conditions: * 13 * * 14 * The above copyright notice and this permission notice shall be included * 15 * in all copies or substantial portions of the Software. * 16 * * 17 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS * 18 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF * 19 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. * 20 * IN NO EVENT SHALL THE ABOVE COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, * 21 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR * 22 * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR * 23 * THE USE OR OTHER DEALINGS IN THE SOFTWARE. * 24 * * 25 * Except as contained in this notice, the name(s) of the above copyright * 26 * holders shall not be used in advertising or otherwise to promote the * 27 * sale, use or other dealings in this Software without prior written * 28 * authorization. * 29 ****************************************************************************/ 30 31 /**************************************************************************** 32 * Author: Thomas E. Dickey * 33 ****************************************************************************/ 34 35 #include <curses.priv.h> 36 37 #include <ctype.h> 38 #include <sys/stat.h> 39 40 #include <tic.h> 41 #include <nc_alloc.h> 42 43 MODULE_ID("$Id: access.c,v 1.5 2010/01/12 23:22:06 nicm Exp $") 44 45 #define LOWERCASE(c) ((isalpha(UChar(c)) && isupper(UChar(c))) ? tolower(UChar(c)) : (c)) 46 47 NCURSES_EXPORT(char *) 48 _nc_rootname(char *path) 49 { 50 char *result = _nc_basename(path); 51 #if !MIXEDCASE_FILENAMES || defined(PROG_EXT) 52 static char *temp; 53 char *s; 54 55 temp = strdup(result); 56 result = temp; 57 #if !MIXEDCASE_FILENAMES 58 for (s = result; *s != '\0'; ++s) { 59 *s = LOWERCASE(*s); 60 } 61 #endif 62 #if defined(PROG_EXT) 63 if ((s = strrchr(result, '.')) != 0) { 64 if (!strcmp(s, PROG_EXT)) 65 *s = '\0'; 66 } 67 #endif 68 #endif 69 return result; 70 } 71 72 /* 73 * Check if a string appears to be an absolute pathname. 74 */ 75 NCURSES_EXPORT(bool) 76 _nc_is_abs_path(const char *path) 77 { 78 #if defined(__EMX__) || defined(__DJGPP__) 79 #define is_pathname(s) ((((s) != 0) && ((s)[0] == '/')) \ 80 || (((s)[0] != 0) && ((s)[1] == ':'))) 81 #else 82 #define is_pathname(s) ((s) != 0 && (s)[0] == '/') 83 #endif 84 return is_pathname(path); 85 } 86 87 /* 88 * Return index of the basename 89 */ 90 NCURSES_EXPORT(unsigned) 91 _nc_pathlast(const char *path) 92 { 93 const char *test = strrchr(path, '/'); 94 #ifdef __EMX__ 95 if (test == 0) 96 test = strrchr(path, '\\'); 97 #endif 98 if (test == 0) 99 test = path; 100 else 101 test++; 102 return (test - path); 103 } 104 105 NCURSES_EXPORT(char *) 106 _nc_basename(char *path) 107 { 108 return path + _nc_pathlast(path); 109 } 110 111 NCURSES_EXPORT(int) 112 _nc_access(const char *path, int mode) 113 { 114 if (access(path, mode) < 0) { 115 if ((mode & W_OK) != 0 116 && errno == ENOENT 117 && strlen(path) < PATH_MAX) { 118 char *leaf, head[PATH_MAX]; 119 120 strlcpy(head, path, sizeof(head)); 121 if ((leaf = _nc_basename(head)) == 0) 122 leaf = head; 123 *leaf = '\0'; 124 if (head == leaf) 125 (void) strlcpy(head, ".", sizeof(head)); 126 127 return access(head, R_OK | W_OK | X_OK); 128 } 129 return -1; 130 } 131 return 0; 132 } 133 134 NCURSES_EXPORT(bool) 135 _nc_is_dir_path(const char *path) 136 { 137 bool result = FALSE; 138 struct stat sb; 139 140 if (stat(path, &sb) == 0 141 && (sb.st_mode & S_IFMT) == S_IFDIR) { 142 result = TRUE; 143 } 144 return result; 145 } 146 147 NCURSES_EXPORT(bool) 148 _nc_is_file_path(const char *path) 149 { 150 bool result = FALSE; 151 struct stat sb; 152 153 if (stat(path, &sb) == 0 154 && (sb.st_mode & S_IFMT) == S_IFREG) { 155 result = TRUE; 156 } 157 return result; 158 } 159 160 #ifndef USE_ROOT_ENVIRON 161 /* 162 * Returns true if we allow application to use environment variables that are 163 * used for searching lists of directories, etc. 164 */ 165 NCURSES_EXPORT(int) 166 _nc_env_access(void) 167 { 168 #if HAVE_ISSETUGID 169 if (issetugid()) 170 return FALSE; 171 #elif HAVE_GETEUID && HAVE_GETEGID 172 if (getuid() != geteuid() 173 || getgid() != getegid()) 174 return FALSE; 175 #endif 176 return getuid() != 0 && geteuid() != 0; /* ...finally, disallow root */ 177 } 178 #endif 179