mDNSMacOSX/dnssec_v2/dnssec_v2_helper.h

   1 //
   2 //      dnssec_v2_helper.h
   3 //      mDNSResponder
   4 //
   5 //      Copyright (c) 2020 Apple Inc. All rights reserved.
   6 //
   7
   8 #ifndef DNSSEC_v2_HELPER_H
   9 #define DNSSEC_v2_HELPER_H
  10
  11 #pragma mark - Includes
  12 #include "mDNSEmbeddedAPI.h"
  13 #if MDNSRESPONDER_SUPPORTS(APPLE, DNSSECv2)
  14
  15 #pragma mark - Macros
  16
  17 // DNSSEC helper
  18
  19 // Used to get the primary question from the current request, it is possible that the current request is started by
  20 // the DNSSEC handler to follow the CNAME, so the primary question should be get from primary_dnssec_context field.
  21 #define GET_PRIMARY_DNSSEC_CONTEXT(C)                   ((C)->primary_dnssec_context == mDNSNULL) ? \
  22                                                                                                         (C) : ((C)->primary_dnssec_context)
  23 #define GET_PRIMARY_REQUEST(C)                                  (GET_PRIMARY_DNSSEC_CONTEXT(C))->me
  24 #define GET_PRIMARY_QUESTION(C)                                 (&((GET_PRIMARY_REQUEST(C))->op.q))
  25 #define GET_REQUEST_ID(C)                                               ((GET_PRIMARY_REQUEST(C))->op.reqID)
  26 #define GET_QUESTION(C)                                                 (&((C)->me->op.q))
  27 #define GET_QUESTION_ID_FROM_Q(Q)                               (mDNSVal16((Q)->TargetQID))
  28 #define GET_QUESTION_ID(C)                                              (GET_QUESTION_ID_FROM_Q(GET_QUESTION(C)))
  29
  30 // string helper
  31 #define DOMAIN_NAME_EQUALS(A, B)                                SameDomainName((const domainname *)(A), (const domainname *)(B))
  32 #define DOMAIN_NAME_LENGTH(NAME)                                DomainNameLength((const domainname *)(NAME))
  33 #define IS_UPPER_CASE(CH)                                               ((CH) >= 'A') && ((CH) <= 'Z')
  34 #define IS_LOWER_CASE(CH)                                               ((CH) >= 'a') && ((CH) <= 'z')
  35 #define TO_LOWER_CASE(CH)                                               ((CH) + ('a' - 'A'))
  36
  37 // print helper
  38 #define DNS_TYPE_STR(TYPE)                                              DNSTypeName((TYPE))
  39 #define NUM_OF_SPACES_PER_TAB                                   4
  40 #define TAB_STR                                                                 "%{public}*s"
  41 #define TAB_PARAM(NUM_OF_TABS)                                  ((NUM_OF_TABS) * (NUM_OF_SPACES_PER_TAB)), ""
  42 // BASE64_STR should be used with BASE64_PARAM
  43 #define BASE64_STR                                                              "%{private, mask.hash}.10s%s"
  44 #define BASE64_PARAM(BASE64)                                    (BASE64), strlen(BASE64) < 11 ? "" : "..."
  45
  46 #pragma mark - Functions
  47
  48
  49
  50 #pragma mark deep_copy_resource_record
  51 /*!
  52  *      @brief
  53  *              Deep copy the record including the name and the rdata.
  54  *      @param dst
  55  *              The copy destination.
  56  *      @param src
  57  *              The copy source.
  58  *      @return
  59  *              Returns mStatus_NoError if no error occurs, other error codes if error occurs
  60  *      @discussion
  61  *              Remember to free the malloced ResourceRecord->name and ResourceRecord->rdata.
  62  */
  63 mDNSexport mStatus
  64 deep_copy_resource_record(ResourceRecord * const _Nonnull dst, const ResourceRecord * const _Nonnull src);
  65
  66 #pragma mark free_resource_record_deep_copied
  67 /*!
  68  *      @brief
  69  *              Free the malloced memory in the ResourceRecord.
  70  *      @param rr
  71  *              The ResourceRecord that has malloced memory inside.
  72  *      @discussion
  73  *              It will only free malloced fields in ResourceRecord, remember to free ResourceRecord itself.
  74  */
  75 mDNSexport void
  76 free_resource_record_deep_copied(ResourceRecord * const _Nonnull rr);
  77
  78 #pragma mark is_root_domain
  79 /*!
  80  *      @brief
  81  *              Given a  DNS format DNS name, determine if it is root.
  82  *      @param domain_name
  83  *              The DNS format domain name.
  84  *      @return
  85  *              Returns true if the domain is root, otherwise return false.
  86  */
  87 mDNSexport mDNSBool
  88 is_root_domain(const mDNSu8 * const _Nonnull domain_name);
  89
  90 #pragma mark is_a_subdomain_of_b
  91 /*!
  92  *      @brief
  93  *              Determine if a_name is a sub domain of b_name
  94  *      @param a_name
  95  *              The child zone or sub domain.
  96  *      @param b_name
  97  *              The parent zone.
  98  *      @return
  99  *              Returns true if a_name is a subdomain of b_name
 100  */
 101 mDNSexport mDNSBool
 102 is_a_subdomain_of_b(const mDNSu8 * const _Nonnull a_name, const mDNSu8 * const _Nonnull b_name);
 103
 104 #pragma mark resource_records_equal
 105 /*!
 106  *      @brief
 107  *              Determine if two records are identical.
 108  *      @return
 109  *              Returns true if two records are identical, false if they are not equal.
 110  */
 111 mDNSexport mDNSBool
 112 resource_records_equal(
 113         const mDNSu16 rr_type_0,                                const mDNSu16 rr_type_1,
 114         const mDNSu16 rr_class_0,                               const mDNSu16 rr_clasee_1,
 115         const mDNSu16 rdata_length_0,                   const mDNSu16 rdata_length_1,
 116         const mDNSu32 name_hash_0,                              const mDNSu32 name_hash_1,
 117         const mDNSu32 rdata_hash_0,                             const mDNSu32 rdata_hash_1,
 118         const mDNSu8 * const _Nonnull name_0,   const mDNSu8 * const _Nonnull name_1,
 119         const mDNSu8 * const _Nonnull rdata_0,  const mDNSu8 * const _Nonnull rdata_1);
 120
 121 #pragma mark dnssec_algorithm_value_to_string
 122 /*!
 123  *      @brief
 124  *              Convert DNSKEY type to string description.
 125  *      @param algorithm
 126  *              The DNSKEY type.
 127  *      @return
 128  *              The corresponding string description of the DNSKEY type.
 129  */
 130 mDNSexport const char * _Nonnull
 131 dnssec_algorithm_value_to_string(const mDNSu8 algorithm);
 132
 133 #pragma mark dnssec_dnskey_flags_to_string
 134 /*!
 135  *      @brief
 136  *              Convert DS hash type to string description.
 137  *      @param digest_type
 138  *              The DS digest type.
 139  *      @return
 140  *              The corresponding string description of the DS digest type.
 141  */
 142 mDNSexport const char * _Nonnull
 143 dnssec_digest_type_value_to_string(const mDNSu8 digest_type);
 144
 145 #pragma mark deep_copy_resource_record
 146 /*!
 147  *      @brief
 148  *              Convert DNSKEY flags to string description.
 149  *      @param flags
 150  *              The DNSKEY flags field
 151  *      @param buffer
 152  *              The string buffer that stores the converted string description.
 153  *      @param buffer_size
 154  *              The total size of the buffer.
 155  *      @return
 156  *              The pointer to the start of the buffer, aka the start of the description.
 157  */
 158 mDNSexport const char * _Nonnull
 159 dnssec_dnskey_flags_to_string(const mDNSu16 flags, char * const _Nonnull buffer, const mDNSu32 buffer_size);
 160
 161 #pragma mark dnssec_epoch_time_to_date_string
 162 /*!
 163  *      @brief
 164  *              Convert epoch time field in RRSIG to string description.
 165  *      @param epoch
 166  *              The epoch time.
 167  *      @param buffer
 168  *              The string buffer that stores the converted string description.
 169  *      @param buffer_size
 170  *              The total size of the buffer.
 171  *      @return
 172  *              The pointer to the start of the buffer, aka the start of the description.
 173  */
 174 mDNSexport const char * _Nonnull
 175 dnssec_epoch_time_to_date_string(const mDNSu32 epoch, char * const _Nonnull buffer, const mDNSu32 buffer_size);
 176
 177 #pragma mark dnssec_nsec3_flags_to_string
 178 /*!
 179  *      @brief
 180  *              Convert NSEC3 flags to string description.
 181  *      @param flags
 182  *              The DNSKEY flags field
 183  *      @param buffer
 184  *              The string buffer that stores the converted string description.
 185  *      @param buffer_size
 186  *              The total size of the buffer.
 187  *      @return
 188  *              The pointer to the start of the buffer, aka the start of the description.
 189  */
 190 mDNSexport const char * _Nonnull
 191 dnssec_nsec3_flags_to_string(const mDNSu8 flags, char * const _Nonnull buffer, const mDNSu32 buffer_size);
 192
 193 #pragma mark get_number_of_labels
 194 /*!
 195  *      @brief
 196  *              Count the number of labels for the given DNS format name.
 197  *      @name
 198  *              The DNS format name.
 199  *      @return
 200  *              The number of labels.
 201  */
 202 mDNSexport mDNSu8
 203 get_number_of_labels(const mDNSu8 * _Nonnull name);
 204
 205 #pragma mark to_lowercase_if_char
 206 /*!
 207  *      @brief
 208  *              Convert the character to lower string if it is alphbeta.
 209  *      @param ch
 210  *              The character.
 211  *      @return
 212  *              The converted character.
 213  */
 214 mDNSexport mDNSu8
 215 to_lowercase_if_char(const mDNSu8 ch);
 216
 217 #endif // MDNSRESPONDER_SUPPORTS(APPLE, DNSSECv2)
 218 #endif // DNSSEC_v2_HELPER_H