bsd/dev/i386/sel_inline.h

   1 /*
   2  * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * The contents of this file constitute Original Code as defined in and
   7  * are subject to the Apple Public Source License Version 1.1 (the
   8  * "License").  You may not use this file except in compliance with the
   9  * License.  Please obtain a copy of the License at
  10  * http://www.apple.com/publicsource and read it before using this file.
  11  *
  12  * This Original Code and all software distributed under the License are
  13  * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  14  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  15  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  16  * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT.  Please see the
  17  * License for the specific language governing rights and limitations
  18  * under the License.
  19  *
  20  * @APPLE_LICENSE_HEADER_END@
  21  */
  22 /*
  23  * Copyright (c) 1992 NeXT Computer, Inc.
  24  *
  25  * Selector value conversion/validation.
  26  *
  27  * HISTORY
  28  *
  29  * 19 June 1992 ? at NeXT
  30  *      Created.
  31  */
  32
  33
  34 static inline
  35 unsigned int
  36 sel_to_selector(
  37     sel_t               sel
  38 )
  39 {
  40     union {
  41         sel_t           sel;
  42         unsigned short  selector;
  43     } tconv;
  44
  45     tconv.sel = sel;
  46
  47     return (tconv.selector);
  48 }
  49
  50 static inline
  51 sel_t
  52 selector_to_sel(
  53     unsigned int        selector
  54 )
  55 {
  56     union {
  57         unsigned short  selector;
  58         sel_t           sel;
  59     } tconv;
  60
  61     tconv.selector = selector;
  62
  63     return (tconv.sel);
  64 }
  65
  66 #if 0
  67 static inline
  68 boolean_t
  69 valid_user_data_selector(
  70     unsigned int        selector
  71 )
  72 {
  73     sel_t               sel = selector_to_sel(selector);
  74
  75     if (selector == 0)
  76         return (TRUE);
  77
  78     if (sel.ti == SEL_LDT)
  79         return (TRUE);
  80     else if (sel.index < GDTSZ) {
  81         data_desc_t     *desc = (data_desc_t *)sel_to_gdt_entry(sel);
  82
  83         if (desc->dpl == USER_PRIV)
  84             return (TRUE);
  85     }
  86
  87     return (FALSE);
  88 }
  89
  90 static inline
  91 boolean_t
  92 valid_user_code_selector(
  93     unsigned int        selector
  94 )
  95 {
  96     sel_t               sel = selector_to_sel(selector);
  97
  98     if (selector == 0)
  99         return (FALSE);
 100
 101     if (sel.ti == SEL_LDT) {
 102         if (sel.rpl == USER_PRIV)
 103             return (TRUE);
 104     }
 105     else if (sel.index < GDTSZ && sel.rpl == USER_PRIV) {
 106         code_desc_t     *desc = (code_desc_t *)sel_to_gdt_entry(sel);
 107
 108         if (desc->dpl == USER_PRIV)
 109             return (TRUE);
 110     }
 111
 112     return (FALSE);
 113 }
 114
 115 static inline
 116 boolean_t
 117 valid_user_stack_selector(
 118     unsigned int        selector
 119 )
 120 {
 121     sel_t               sel = selector_to_sel(selector);
 122
 123     if (selector == 0)
 124         return (FALSE);
 125
 126     if (sel.ti == SEL_LDT) {
 127         if (sel.rpl == USER_PRIV)
 128             return (TRUE);
 129     }
 130     else if (sel.index < GDTSZ && sel.rpl == USER_PRIV) {
 131         data_desc_t     *desc = (data_desc_t *)sel_to_gdt_entry(sel);
 132
 133         if (desc->dpl == USER_PRIV)
 134             return (TRUE);
 135     }
 136
 137     return (FALSE);
 138 }
 139 #endif