workbench/network/stacks/AROSTCP/netlib/chmod.c

   1 /* $Id$
   2  *
   3  *      chmod.c - chmod() for usergroup link library
   4  *
   5  *      Copyright © 1994 AmiTCP/IP Group,
   6  *                       Network Solutions Development Inc.
   7  *                       All rights reserved.
   8  *
   9  *      This function is based on SetOwner37 code
  10  *      Copyright © 1993 by Geert Uytterhoeven
  11  */
  12
  13 /****** net.lib/chmod *********************************************************
  14
  15     NAME
  16         chmod, fchmod - change mode of file
  17
  18     SYNOPSIS
  19         #include <sys/stat.h>
  20
  21         int chmod(const char *path, mode_t mode);
  22
  23         int fchmod(int fd, mode_t mode);
  24
  25     DESCRIPTION
  26         The function chmod() sets the file permission bits of the file
  27         specified by the pathname path to mode. Fchmod() sets the permission
  28         bits of the specified file descriptor fd. Chmod() verifies that the
  29         process owner (user) either owns the file specified by path (or fd),
  30         or is the super-user.  A mode is created from or'd permission bit
  31         masks defined in <sys/stat.h>:
  32
  33               #define S_IRWXU 0000700    \* RWX mask for owner *\
  34               #define S_IRUSR 0000400    \* R for owner *\
  35               #define S_IWUSR 0000200    \* W for owner *\
  36               #define S_IXUSR 0000100    \* X for owner *\
  37
  38               #define S_IRWXG 0000070    \* RWX mask for group *\
  39               #define S_IRGRP 0000040    \* R for group *\
  40               #define S_IWGRP 0000020    \* W for group *\
  41               #define S_IXGRP 0000010    \* X for group *\
  42
  43               #define S_IRWXO 0000007    \* RWX mask for other *\
  44               #define S_IROTH 0000004    \* R for other *\
  45               #define S_IWOTH 0000002    \* W for other *\
  46               #define S_IXOTH 0000001    \* X for other *\
  47
  48               #define S_ISUID 0004000    \* set user id on execution *\
  49               #define S_ISGID 0002000    \* set group id on execution *\
  50               #define S_ISVTX 0001000    \* save swapped text even after use *\
  51
  52         The ISVTX (the sticky bit) indicates to the system which executable
  53         files are shareable (pure).
  54
  55         Writing or changing the owner of a file turns off the set-user-id
  56         and set-group-id bits unless the user is the super-user.  This makes
  57         the system somewhat more secure by protecting set-user-id
  58         (set-group-id) files from remaining set-user-id (set-group-id) if
  59         they are modified.
  60
  61     RETURN VALUES
  62         Upon successful completion, a value of 0 is returned.  Otherwise, a
  63         value of -1 is returned and errno is set to indicate the error.
  64
  65     ERRORS
  66         Chmod() will fail and the file mode will be unchanged if:
  67
  68         [ENOTDIR]     A component of the path prefix is not a directory.
  69
  70         [ENAMETOOLONG]
  71                       A component of a pathname exceeded 255 characters, or
  72                       an entire path name exceeded 1023 characters.
  73
  74         [ENOENT]      The named file does not exist.
  75
  76         [EACCES]      Search permission is denied for a component of the
  77                       path prefix.
  78
  79         [EPERM]       The effective user ID does not match the owner of the
  80                       file and the effective user ID is not the super-user.
  81
  82         [EROFS]       The named file resides on a read-only file system.
  83
  84         [EFAULT]      Path points outside the process's allocated address
  85                       space.
  86
  87         [EIO]         An I/O error occurred while reading from or writing to
  88                       the file system.
  89
  90         Fchmod() will fail if:
  91
  92         [EBADF]       The descriptor is not valid.
  93
  94         [EINVAL]      Fd refers to a socket, not to a file.
  95
  96         [EROFS]       The file resides on a read-only file system.
  97
  98         [EIO]         An I/O error occurred while reading from or writing to
  99                       the file system.
 100
 101     NOTES
 102         This call is provided for Unix compatibility.  It does not know all
 103         Amiga protection bits (Delete, Archive, Script).  The archive and
 104         script bits are cleared, Delete set according the Write bit.
 105
 106     SEE ALSO
 107         open(),  chown(),  stat()
 108
 109 *****************************************************************************
 110 */
 111
 112 #include <libraries/usergroup.h>
 113 #include <proto/dos.h>
 114
 115 #include <sys/types.h>
 116 #include <sys/stat.h>
 117
 118 #include "fibex.h"
 119 #include "netlib.h"
 120
 121 /*
 122  * rwx -> rwed
 123  */
 124 const static BYTE pbits[8] =
 125 {
 126   0, 0X2, 0X5, 0X7, 0X8, 0XA, 0XD, 0XF,
 127 };
 128
 129 int chmod(const char *path, mode_t mode)
 130 {
 131   LONG prot =
 132     (pbits[mode & 7] << FIBB_OTR_DELETE) |
 133       (pbits[(mode >> 3) & 7] << FIBB_GRP_DELETE) |
 134         (pbits[(mode >> 6) & 7] ^ 0xf);
 135
 136   if (mode & S_ISVTX)
 137     prot |= FIBF_PURE;
 138   if (mode & S_ISUID)
 139     prot |= FIBF_SUID;
 140   if (mode & S_ISGID)
 141     prot |= FIBF_SGID;
 142
 143   if (!SetProtection((STRPTR)path, prot)) {
 144     set_errno(IoErr());
 145     return -1;
 146   } else {
 147     return 0;
 148   }
 149 }
 150
 151 #ifdef DEBUGGING
 152 #include <proto/usergroup.h>
 153 #include <stdlib.h>
 154 #include <string.h>
 155 #include <exec/execbase.h>
 156 #include <ctype.h>
 157
 158 int errno;
 159 extern struct ExecBase *SysBase;
 160
 161 void PrintUserFault(LONG code, const UBYTE *banner);
 162
 163 const static char usage[] = "usage: chmod [-fR] mode file ...";
 164
 165 void main(int argc, char *argv[])
 166 {
 167   struct Process *p = (struct Process *)SysBase->ThisTask;
 168   BPTR Stderr = p->pr_CES ? p->pr_CES : p->pr_COS;
 169
 170   short perrors = 1, recursive = 0;
 171   char *modenum; mode_t mode;
 172
 173   while (argc > 1 && argv[1][0] == '-') {
 174     switch (argv[1][1]) {
 175     case 'f':
 176       perrors = 0;
 177       break;
 178     case 'R':
 179       recursive = 1;
 180       break;
 181     default:
 182       FPrintf(Stderr, usage);
 183       exit(10);
 184     }
 185     argv++, argc--;
 186   }
 187
 188   if (argc <= 2) {
 189     FPrintf(Stderr, usage);
 190     exit(10);
 191   }
 192
 193   modenum = argv[1]; argv++, argc--;
 194
 195   mode = 0;
 196   while (isdigit(*modenum)) {
 197     mode <<= 3;
 198     mode += *modenum++ - '0';
 199   }
 200
 201   if (*modenum) {
 202     FPrintf(Stderr, usage);
 203     exit(10);
 204   }
 205
 206   while (argc-- > 1) {
 207     if (chmod(argv++[1], mode) == -1) {
 208       if (perrors)
 209         PrintUserFault(errno, "chmod");
 210       exit(RETURN_ERROR);
 211     }
 212   }
 213
 214   exit(0);
 215 }
 216 #endif