external/bsd/ntp/dist/lib/isc/fsaccess.c

   1 /*      $NetBSD$        */
   2
   3 /*
   4  * Copyright (C) 2004, 2005, 2007  Internet Systems Consortium, Inc. ("ISC")
   5  * Copyright (C) 2000, 2001  Internet Software Consortium.
   6  *
   7  * Permission to use, copy, modify, and/or distribute this software for any
   8  * purpose with or without fee is hereby granted, provided that the above
   9  * copyright notice and this permission notice appear in all copies.
  10  *
  11  * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
  12  * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
  13  * AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
  14  * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
  15  * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
  16  * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
  17  * PERFORMANCE OF THIS SOFTWARE.
  18  */
  19
  20 /* Id: fsaccess.c,v 1.10 2007/06/19 23:47:17 tbox Exp */
  21
  22 /*! \file
  23  * \brief
  24  * This file contains the OS-independent functionality of the API.
  25  */
  26 #include <isc/fsaccess.h>
  27 #include <isc/result.h>
  28 #include <isc/util.h>
  29
  30 /*!
  31  * Shorthand.  Maybe ISC__FSACCESS_PERMISSIONBITS should not even be in
  32  * <isc/fsaccess.h>.  Could check consistency with sizeof(isc_fsaccess_t)
  33  * and the number of bits in each function.
  34  */
  35 #define STEP            (ISC__FSACCESS_PERMISSIONBITS)
  36 #define GROUP           (STEP)
  37 #define OTHER           (STEP * 2)
  38
  39 void
  40 isc_fsaccess_add(int trustee, int permission, isc_fsaccess_t *access) {
  41         REQUIRE(trustee <= 0x7);
  42         REQUIRE(permission <= 0xFF);
  43
  44         if ((trustee & ISC_FSACCESS_OWNER) != 0)
  45                 *access |= permission;
  46
  47         if ((trustee & ISC_FSACCESS_GROUP) != 0)
  48                 *access |= (permission << GROUP);
  49
  50         if ((trustee & ISC_FSACCESS_OTHER) != 0)
  51                 *access |= (permission << OTHER);
  52 }
  53
  54 void
  55 isc_fsaccess_remove(int trustee, int permission, isc_fsaccess_t *access) {
  56         REQUIRE(trustee <= 0x7);
  57         REQUIRE(permission <= 0xFF);
  58
  59
  60         if ((trustee & ISC_FSACCESS_OWNER) != 0)
  61                 *access &= ~permission;
  62
  63         if ((trustee & ISC_FSACCESS_GROUP) != 0)
  64                 *access &= ~(permission << GROUP);
  65
  66         if ((trustee & ISC_FSACCESS_OTHER) != 0)
  67                 *access &= ~(permission << OTHER);
  68 }
  69
  70 static isc_result_t
  71 check_bad_bits(isc_fsaccess_t access, isc_boolean_t is_dir) {
  72         isc_fsaccess_t bits;
  73
  74         /*
  75          * Check for disallowed user bits.
  76          */
  77         if (is_dir)
  78                 bits = ISC_FSACCESS_READ |
  79                        ISC_FSACCESS_WRITE |
  80                        ISC_FSACCESS_EXECUTE;
  81         else
  82                 bits = ISC_FSACCESS_CREATECHILD |
  83                        ISC_FSACCESS_ACCESSCHILD |
  84                        ISC_FSACCESS_DELETECHILD |
  85                        ISC_FSACCESS_LISTDIRECTORY;
  86
  87         /*
  88          * Set group bad bits.
  89          */
  90         bits |= bits << STEP;
  91         /*
  92          * Set other bad bits.
  93          */
  94         bits |= bits << STEP;
  95
  96         if ((access & bits) != 0) {
  97                 if (is_dir)
  98                         return (ISC_R_NOTFILE);
  99                 else
 100                         return (ISC_R_NOTDIRECTORY);
 101         }
 102
 103         return (ISC_R_SUCCESS);
 104 }