dnsinfo/dnsinfo_private.h

   1 /*
   2  * Copyright (c) 2004 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * This file contains Original Code and/or Modifications of Original Code
   7  * as defined in and that are subject to the Apple Public Source License
   8  * Version 2.0 (the 'License'). You may not use this file except in
   9  * compliance with the License. Please obtain a copy of the License at
  10  * http://www.opensource.apple.com/apsl/ and read it before using this
  11  * file.
  12  *
  13  * The Original Code and all software distributed under the License are
  14  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  15  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  16  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  17  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  18  * Please see the License for the specific language governing rights and
  19  * limitations under the License.
  20  *
  21  * @APPLE_LICENSE_HEADER_END@
  22  */
  23
  24 #ifndef __DNSINFO_PRIVATE_H__
  25 #define __DNSINFO_PRIVATE_H__
  26
  27
  28 #include <stdint.h>
  29 #include <sys/types.h>
  30 #include <sys/socket.h>
  31 #include <netinet/in.h>
  32 #include <mach/mach.h>
  33
  34 #include "dnsinfo.h"
  35
  36
  37 /*
  38  * What's all of this stuff about???
  39  *
  40  * In order to minimize the amount of data conversions associated with
  41  * storing, retrieving, and accessing the systems DNS configuration I
  42  * have opted to create a memory image filled with the actual data
  43  * types / structures that would be used by those applications which
  44  * make use of these APIS.  The implication here is that we use
  45  * sockaddr's for addresses, char *'s for strings, etc.
  46  *
  47  * To achieve this goal the APIs which are used to store and access the
  48  * configuration data build and use a single buffer of the relevant
  49  * bits.  When multiple instances of a given type / structure are needed
  50  * we maintain a count, the actual data, and when the configuration has
  51  * been unpacked, arrays of pointers to the data.
  52  *
  53  * In memory, the data looks as follows:
  54  *
  55  * +-------------------------------------------------------------------+
  56  * | struct _dns_config_buf_t                                          |
  57  * +-+-------------+---------------------------------------------------+
  58  * | | config      | struct dns_config_t                               |
  59  * | |             +-+--------------+----------------------------------+
  60  * | |             | | n_resolver   | int32_t                          | <- # of name resolvers
  61  * | |             | +--------------+----------------------------------+
  62  * | |             | | resolver     | dns_resolver_t **                | <- not used during creation, filled
  63  * | |             | |              |                                  |    in with pointer to a list of
  64  * | |             | |              |                                  |    resolver configurations which be
  65  * | |             | |              |                                  |    established in the "padding"
  66  * | |             | +--------------+----------------------------------+
  67  * | |             | | ...          | ...                              |
  68  * | +-------------+-+--------------+----------------------------------+
  69  * | | n_attribute | uint32_t                                          | <- how many bytes of "attribute"
  70  * | |             |                                                   |    data is associated with the
  71  * | |             |                                                   |    configuration
  72  * |-+-------------+---------------------------------------------------+
  73  * | | n_padding   | uint32_t                                          | <- how many additional bytes
  74  * | |             |                                                   |    for arrays (of pointers), ...
  75  * +-+-------------+---------------------------------------------------+
  76  * | struct dns_attribute_t                                            |
  77  * |-+-------------+---------------------------------------------------+
  78  * | | type        | uint32_t                                          | <- type of attribute (e.g. CONFIG_ATTRIBUTE_RESOLVER)
  79  * | +-------------+---------------------------------------------------+
  80  * | | length      | uint32_t                                          | <- length of the attribute
  81  * | +-------------+---------------------------------------------------+
  82  * | | attribute   | struct _dns_resolver_buf_t                        | <- the attribute data (resolver configuration #1)
  83  * | |             +-+-------------+-----------------------------------+
  84  * | |             | | resolver    | struct dns_resolver_t             |
  85  * | |             | |             +--------------+--------------------+
  86  * | |             | |             | domain       | char *             | <- not used during creation,
  87  * | |             | |             |              |                    |    filled in with pointer to
  88  * | |             | |             |              |                    |    domain name in the "padding"
  89  * | |             | |             +--------------+--------------------+
  90  * | |             | |             | n_nameserver | int32_t            | <- # of name server addresses
  91  * | |             | |             +--------------+--------------------+
  92  * | |             | |             | nameserver   | struct sockaddr ** | <- not used during creation,
  93  * | |             | |             |              |                    |    filled in with pointer to
  94  * | |             | |             |              |                    |    a list of addresses which
  95  * | |             | |             |              |                    |    will be established in the
  96  * | |             | |             |              |                    |    "padding"
  97  * | |             | |             +--------------+--------------------+
  98  * | |             | |             | ...                               |
  99  * | |             +-+-------------+--------------+--------------------+
 100  * | |             | | n_attribute | uint32_t                          |
 101  * | |             +-+-------------+-----------------------------------+
 102  * | |             | | attribute   | struct dns_attribute_t            |
 103  * | |             | |             +-+-----------+---------------------+
 104  * | |             | |             | | type      | uint32_t            | <- type of attribute (e.g. RESOLVER_ATTRIBUTE_DOMAIN)
 105  * | |             | |             | +-----------+---------------------+
 106  * | |             | |             | | length    | uint32_t            | <- length of the attribute
 107  * | |             | |             | +-----------+---------------------+
 108  * | |             | |             | | attribute |                     | <- the attribute data ("apple.com")
 109  * | |             +-+-------------+-------------+---------------------+
 110  * | |             | | attribute   | struct dns_attribute_t            |
 111  * | |             | |             +-+-----------+---------------------+
 112  * | |             | |             | | type      | uint32_t            | <- type of attribute (e.g. RESOLVER_ATTRIBUTE_ADDRESS)
 113  * | |             | |             | +-----------+---------------------+
 114  * | |             | |             | | length    | uint32_t            | <- length of the attribute
 115  * | |             | |             | +-----------+---------------------+
 116  * | |             | |             | | attribute |                     | <- the attribute data ("struct sockaddr_in" #1)
 117  * | |             +---------------+-----------------------------------+
 118  * | |             | | attribute   | struct dns_attribute_t            |
 119  * | |             | |             +-+-----------+---------------------+
 120  * | |             | |             | | type      | uint32_t            | <- type of attribute (e.g. RESOLVER_ATTRIBUTE_ADDRESS)
 121  * | |             | |             | +-----------+---------------------+
 122  * | |             | |             | | length    | uint32_t            | <- length of the attribute
 123  * | |             | |             | +-----------+---------------------+
 124  * | |             | |             | | attribute |                     | <- the attribute data ("struct sockaddr_in" #2)
 125  * | |             +---------------+-----------------------------------+
 126  * | |             | ...                                               |
 127  * +-+-------------+---------------------------------------------------+
 128  * | | attribute   | struct _dns_resolver_buf_t                        | <- the attribute data (resolver configuration #2)
 129  * | |             +---------------+-----------------------------------+
 130  * | |             | ...                                               |
 131  * +---------------+---------------------------------------------------+
 132  * | | ...                                                             |
 133  * +---------------+---------------------------------------------------+
 134  *
 135  * When the data is unpacked the "n_padding" additional bytes
 136  * specified in configuration buffer will be allocated at the
 137  * end of this buffer. Arrays of pointers will be allocated
 138  * within the extra space array element (an "attribute") is
 139  * encountered the pointer reference will be filled in.
 140  */
 141
 142
 143 // configuration buffer attributes
 144 enum {
 145         CONFIG_ATTRIBUTE_RESOLVER       = 1
 146 };
 147
 148
 149 // resolver buffer attributes
 150 enum {
 151         RESOLVER_ATTRIBUTE_DOMAIN       = 10,
 152         RESOLVER_ATTRIBUTE_ADDRESS,
 153         RESOLVER_ATTRIBUTE_SEARCH,
 154         RESOLVER_ATTRIBUTE_SORTADDR,
 155         RESOLVER_ATTRIBUTE_OPTIONS
 156 };
 157
 158
 159 typedef struct {
 160         uint32_t        type;
 161         uint32_t        length;
 162         uint8_t         attribute[0];
 163 } dns_attribute_t;
 164
 165
 166 typedef struct {
 167         dns_config_t    config;
 168         uint32_t        n_attribute;
 169         uint32_t        n_padding;
 170         uint8_t         attribute[0];
 171 } _dns_config_buf_t;
 172
 173
 174 typedef struct {
 175         dns_resolver_t  resolver;
 176         uint32_t        n_attribute;
 177         uint8_t         attribute[0];
 178 } _dns_resolver_buf_t;
 179
 180
 181 const char *    _dns_configuration_notify_key();
 182 mach_port_t     _dns_configuration_server_port();
 183
 184 #endif __DNSINFO_PRIVATE_H__