coreutils/chown.c

   1 /*
   2  * Mini chown/chmod/chgrp implementation for busybox
   3  *
   4  * Copyright (C) 1998 by Erik Andersen <andersee@debian.org>
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  14  * General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, write to the Free Software
  18  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  19  *
  20  */
  21
  22 #include <stdio.h>
  23 #include <grp.h>
  24 #include <pwd.h>
  25 #include "internal.h"
  26
  27
  28 static int uid=-1;
  29 static int gid=0;
  30 static int whichApp;
  31 static char* invocationName=NULL;
  32 static mode_t mode=7777;
  33
  34
  35 #define CHGRP_APP   1
  36 #define CHOWN_APP   2
  37 #define CHMOD_APP   3
  38
  39 static const char chgrp_usage[] = "[OPTION]... GROUP FILE...\n"
  40     "Change the group membership of each FILE to GROUP.\n"
  41     "\n\tOptions:\n" "\t-R\tchange files and directories recursively\n";
  42 static const char chown_usage[] = "[OPTION]...  OWNER[.[GROUP] FILE...\n"
  43     "Change the owner and/or group of each FILE to OWNER and/or GROUP.\n"
  44     "\n\tOptions:\n" "\t-R\tchange files and directories recursively\n";
  45 static const char chmod_usage[] = "[-R] MODE[,MODE]... FILE...\n"
  46 "Each MODE is one or more of the letters ugoa, one of the symbols +-= and\n"
  47 "one or more of the letters rwxst.\n\n"
  48  "\t-R\tchange files and directories recursively.\n";
  49
  50
  51
  52 static int fileAction(const char *fileName)
  53 {
  54     struct stat statBuf;
  55     if (stat(fileName, &statBuf) < 0) {
  56         switch (whichApp) {
  57             case CHGRP_APP:
  58             case CHOWN_APP:
  59                 if (chown(fileName, ((whichApp==CHOWN_APP)? uid: statBuf.st_uid), gid) < 0)
  60                     return( TRUE);
  61             case CHMOD_APP:
  62                 if (chmod(fileName, mode))
  63                     return( TRUE);
  64         }
  65     }
  66     perror(fileName);
  67     return( FALSE);
  68 }
  69
  70 /* [ugoa]{+|-|=}[rwxstl] */
  71 int parse_mode( const char* s, mode_t* or, mode_t* and, int* group_execute)
  72 {
  73         mode_t  mode = 0;
  74         mode_t  groups = S_ISVTX;
  75         char    type;
  76         char    c;
  77
  78         do {
  79                 for ( ; ; ) {
  80                         switch ( c = *s++ ) {
  81                         case '\0':
  82                                 return (FALSE);
  83                         case 'u':
  84                                 groups |= S_ISUID|S_IRWXU;
  85                                 continue;
  86                         case 'g':
  87                                 groups |= S_ISGID|S_IRWXG;
  88                                 continue;
  89                         case 'o':
  90                                 groups |= S_IRWXO;
  91                                 continue;
  92                         case 'a':
  93                                 groups |= S_ISUID|S_ISGID|S_IRWXU|S_IRWXG|S_IRWXO;
  94                                 continue;
  95                         case '+':
  96                         case '=':
  97                         case '-':
  98                                 type = c;
  99                                 if ( groups == S_ISVTX ) /* The default is "all" */
 100                                         groups |= S_ISUID|S_ISGID|S_IRWXU|S_IRWXG|S_IRWXO;
 101                                 break;
 102                         default:
 103                                 if ( c >= '0' && c <= '7' && mode == 0 && groups == S_ISVTX ) {
 104                                         *and = 0;
 105                                         *or = strtol(--s, 0, 010);
 106                                         return (TRUE);
 107                                 }
 108                                 else
 109                                         return (FALSE);
 110                         }
 111                         break;
 112                 }
 113
 114                 while ( (c = *s++) != '\0' ) {
 115                         switch ( c ) {
 116                         case ',':
 117                                 break;
 118                         case 'r':
 119                                 mode |= S_IRUSR|S_IRGRP|S_IROTH;
 120                                 continue;
 121                         case 'w':
 122                                 mode |= S_IWUSR|S_IWGRP|S_IWOTH;
 123                                 continue;
 124                         case 'x':
 125                                 mode |= S_IXUSR|S_IXGRP|S_IXOTH;
 126                                 continue;
 127                         case 's':
 128                                 if ( group_execute != 0 && (groups & S_IRWXG) ) {
 129                                         if ( *group_execute < 0 )
 130                                                 return (FALSE);
 131                                         if ( type != '-' ) {
 132                                                 mode |= S_IXGRP;
 133                                                 *group_execute = 1;
 134                                         }
 135                                 }
 136                                 mode |= S_ISUID|S_ISGID;
 137                                 continue;
 138                         case 'l':
 139                                 if ( *group_execute > 0 )
 140                                         return (FALSE);
 141                                 if ( type != '-' ) {
 142                                         *and &= ~S_IXGRP;
 143                                         *group_execute = -1;
 144                                 }
 145                                 mode |= S_ISGID;
 146                                 groups |= S_ISGID;
 147                                 continue;
 148                         case 't':
 149                                 mode |= S_ISVTX;
 150                                 continue;
 151                         default:
 152                                 return (FALSE);
 153                         }
 154                         break;
 155                 }
 156                 switch ( type ) {
 157                 case '=':
 158                         *and &= ~(groups);
 159                         /* fall through */
 160                 case '+':
 161                         *or |= mode & groups;
 162                         break;
 163                 case '-':
 164                         *and &= ~(mode & groups);
 165                         *or &= *and;
 166                         break;
 167                 }
 168         } while ( c == ',' );
 169         return (TRUE);
 170 }
 171
 172
 173 int chmod_chown_chgrp_main(int argc, char **argv)
 174 {
 175     struct group *grp;
 176     struct passwd *pwd;
 177     int recursiveFlag=FALSE;
 178     char *groupName;
 179
 180
 181     whichApp = (strcmp(*argv, "chown")==0)? CHOWN_APP : (strcmp(*argv, "chmod")==0)? CHMOD_APP : CHGRP_APP;
 182
 183     if (argc < 2) {
 184         fprintf(stderr, "Usage: %s %s", *argv,
 185                 (whichApp==TRUE)? chown_usage : chgrp_usage);
 186         exit( FALSE);
 187     }
 188     invocationName=*argv;
 189     argc--;
 190     argv++;
 191
 192     /* Parse options */
 193     while (**argv == '-') {
 194         while (*++(*argv)) switch (**argv) {
 195             case 'R':
 196                 recursiveFlag = TRUE;
 197                 break;
 198             default:
 199                 fprintf(stderr, "Unknown option: %c\n", **argv);
 200                 exit( FALSE);
 201         }
 202         argc--;
 203         argv++;
 204     }
 205
 206     if ( whichApp == CHMOD_APP ) {
 207         /* Find the specified modes */
 208         if ( parse_mode(*argv, &orWithMode, &andWithMode, 0) == FALSE ) {
 209             fprintf(stderr, "%s: Unknown mode: %s\n", invocationName, *argv);
 210             exit( FALSE);
 211         }
 212         mode &= andWithMode;
 213         mode |= orWithMode;
 214     } else {
 215
 216         /* Find the selected group */
 217         groupName = strchr(*argv, '.');
 218         if ( whichApp==TRUE && groupName )
 219             *groupName++ = '\0';
 220         else
 221             groupName = *argv;
 222         grp = getgrnam(groupName);
 223         if (grp == NULL) {
 224             fprintf(stderr, "%s: Unknown group name: %s\n", invocationName, groupName);
 225             exit( FALSE);
 226         }
 227         gid = grp->gr_gid;
 228
 229         /* Find the selected user (if appropriate)  */
 230         if (whichApp==TRUE) {
 231             pwd = getpwnam(*argv);
 232             if (pwd == NULL) {
 233                 fprintf(stderr, "%s: Unknown user name: %s\n", invocationName, *argv);
 234                 exit( FALSE);
 235             }
 236             uid = pwd->pw_uid;
 237         }
 238     }
 239
 240     /* Ok, ready to do the deed now */
 241     if (argc <= 1) {
 242         fprintf(stderr, "%s: too few arguments", invocationName);
 243         exit( FALSE);
 244     }
 245     while (argc-- > 1) {
 246         argv++;
 247         recursiveAction( *argv, recursiveFlag, TRUE, fileAction, fileAction);
 248     }
 249     exit(TRUE);
 250 }
 251