1 /**************************************************************************** 2 * Copyright (c) 1998-2011,2012 Free Software Foundation, Inc. * 3 * * 4 * Permission is hereby granted, free of charge, to any person obtaining a * 5 * copy of this software and associated documentation files (the * 6 * "Software"), to deal in the Software without restriction, including * 7 * without limitation the rights to use, copy, modify, merge, publish, * 8 * distribute, distribute with modifications, sublicense, and/or sell * 9 * copies of the Software, and to permit persons to whom the Software is * 10 * furnished to do so, subject to the following conditions: * 11 * * 12 * The above copyright notice and this permission notice shall be included * 13 * in all copies or substantial portions of the Software. * 14 * * 15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS * 16 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF * 17 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. * 18 * IN NO EVENT SHALL THE ABOVE COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, * 19 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR * 20 * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR * 21 * THE USE OR OTHER DEALINGS IN THE SOFTWARE. * 22 * * 23 * Except as contained in this notice, the name(s) of the above copyright * 24 * holders shall not be used in advertising or otherwise to promote the * 25 * sale, use or other dealings in this Software without prior written * 26 * authorization. * 27 ****************************************************************************/ 28 29 /**************************************************************************** 30 * Author: Thomas E. Dickey * 31 ****************************************************************************/ 32 33 #include <curses.priv.h> 34 35 #include <ctype.h> 36 37 #include <tic.h> 38 39 MODULE_ID("$Id: access.c,v 1.23 2012/09/01 19:21:29 tom Exp $") 40 41 #ifdef __TANDEM 42 #define ROOT_UID 65535 43 #endif 44 45 #ifndef ROOT_UID 46 #define ROOT_UID 0 47 #endif 48 49 #define LOWERCASE(c) ((isalpha(UChar(c)) && isupper(UChar(c))) ? tolower(UChar(c)) : (c)) 50 51 NCURSES_EXPORT(char *) 52 _nc_rootname(char *path) 53 { 54 char *result = _nc_basename(path); 55 #if !MIXEDCASE_FILENAMES || defined(PROG_EXT) 56 static char *temp; 57 char *s; 58 59 temp = strdup(result); 60 result = temp; 61 #if !MIXEDCASE_FILENAMES 62 for (s = result; *s != '\0'; ++s) { 63 *s = (char) LOWERCASE(*s); 64 } 65 #endif 66 #if defined(PROG_EXT) 67 if ((s = strrchr(result, '.')) != 0) { 68 if (!strcmp(s, PROG_EXT)) 69 *s = '\0'; 70 } 71 #endif 72 #endif 73 return result; 74 } 75 76 /* 77 * Check if a string appears to be an absolute pathname. 78 */ 79 NCURSES_EXPORT(bool) 80 _nc_is_abs_path(const char *path) 81 { 82 #if defined(__EMX__) || defined(__DJGPP__) 83 #define is_pathname(s) ((((s) != 0) && ((s)[0] == '/')) \ 84 || (((s)[0] != 0) && ((s)[1] == ':'))) 85 #else 86 #define is_pathname(s) ((s) != 0 && (s)[0] == '/') 87 #endif 88 return is_pathname(path); 89 } 90 91 /* 92 * Return index of the basename 93 */ 94 NCURSES_EXPORT(unsigned) 95 _nc_pathlast(const char *path) 96 { 97 const char *test = strrchr(path, '/'); 98 #ifdef __EMX__ 99 if (test == 0) 100 test = strrchr(path, '\\'); 101 #endif 102 if (test == 0) 103 test = path; 104 else 105 test++; 106 return (unsigned) (test - path); 107 } 108 109 NCURSES_EXPORT(char *) 110 _nc_basename(char *path) 111 { 112 return path + _nc_pathlast(path); 113 } 114 115 NCURSES_EXPORT(int) 116 _nc_access(const char *path, int mode) 117 { 118 int result; 119 120 if (path == 0) { 121 result = -1; 122 } else if (access(path, mode) < 0) { 123 if ((mode & W_OK) != 0 124 && errno == ENOENT 125 && strlen(path) < PATH_MAX) { 126 char head[PATH_MAX]; 127 char *leaf; 128 129 _nc_STRCPY(head, path, sizeof(head)); 130 leaf = _nc_basename(head); 131 if (leaf == 0) 132 leaf = head; 133 *leaf = '\0'; 134 if (head == leaf) 135 _nc_STRCPY(head, ".", sizeof(head)); 136 137 result = access(head, R_OK | W_OK | X_OK); 138 } else { 139 result = -1; 140 } 141 } else { 142 result = 0; 143 } 144 return result; 145 } 146 147 NCURSES_EXPORT(bool) 148 _nc_is_dir_path(const char *path) 149 { 150 bool result = FALSE; 151 struct stat sb; 152 153 if (stat(path, &sb) == 0 154 && S_ISDIR(sb.st_mode)) { 155 result = TRUE; 156 } 157 return result; 158 } 159 160 NCURSES_EXPORT(bool) 161 _nc_is_file_path(const char *path) 162 { 163 bool result = FALSE; 164 struct stat sb; 165 166 if (stat(path, &sb) == 0 167 && S_ISREG(sb.st_mode)) { 168 result = TRUE; 169 } 170 return result; 171 } 172 173 #ifndef USE_ROOT_ENVIRON 174 /* 175 * Returns true if we allow application to use environment variables that are 176 * used for searching lists of directories, etc. 177 */ 178 NCURSES_EXPORT(int) 179 _nc_env_access(void) 180 { 181 #if HAVE_ISSETUGID 182 if (issetugid()) 183 return FALSE; 184 #elif HAVE_GETEUID && HAVE_GETEGID 185 if (getuid() != geteuid() 186 || getgid() != getegid()) 187 return FALSE; 188 #endif 189 /* ...finally, disallow root */ 190 return (getuid() != ROOT_UID) && (geteuid() != ROOT_UID); 191 } 192 #endif 193