1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
// Copyright 2015-2021 Benjamin Fry <benjaminfry@me.com>
//
// Licensed under the Apache License, Version 2.0, <LICENSE-APACHE or
// http://apache.org/licenses/LICENSE-2.0> or the MIT license <LICENSE-MIT or
// http://opensource.org/licenses/MIT>, at your option. This file may not be
// copied, modified, or distributed except according to those terms.

//! record data enum variants

#![allow(deprecated)] // allows us to deprecate RData types

use std::cmp::Ordering;
#[cfg(test)]
use std::convert::From;
use std::fmt;
use std::net::{IpAddr, Ipv4Addr, Ipv6Addr};

#[cfg(feature = "serde-config")]
use serde::{Deserialize, Serialize};

use enum_as_inner::EnumAsInner;
use log::{trace, warn};

use super::domain::Name;
use super::rdata;
use super::rdata::{
    CAA, CSYNC, HINFO, MX, NAPTR, NULL, OPENPGPKEY, OPT, SOA, SRV, SSHFP, SVCB, TLSA, TXT,
};
use super::record_type::RecordType;
use crate::error::*;
use crate::serialize::binary::*;

#[cfg(feature = "dnssec")]
use super::dnssec::rdata::DNSSECRData;

/// Record data enum variants
///
/// [RFC 1035](https://tools.ietf.org/html/rfc1035), DOMAIN NAMES - IMPLEMENTATION AND SPECIFICATION, November 1987
///
/// ```text
/// 3.3. Standard RRs
///
/// The following RR definitions are expected to occur, at least
/// potentially, in all classes.  In particular, NS, SOA, CNAME, and PTR
/// will be used in all classes, and have the same format in all classes.
/// Because their RDATA format is known, all domain names in the RDATA
/// section of these RRs may be compressed.
///
/// <domain-name> is a domain name represented as a series of labels, and
/// terminated by a label with zero length.  <character-string> is a single
/// length octet followed by that number of characters.  <character-string>
/// is treated as binary information, and can be up to 256 characters in
/// length (including the length octet).
/// ```
#[cfg_attr(feature = "serde-config", derive(Deserialize, Serialize))]
#[derive(Debug, EnumAsInner, PartialEq, Clone, Eq)]
#[non_exhaustive]
pub enum RData {
    /// ```text
    /// -- RFC 1035 -- Domain Implementation and Specification    November 1987
    ///
    /// 3.4. Internet specific RRs
    ///
    /// 3.4.1. A RDATA format
    ///
    ///     +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
    ///     |                    ADDRESS                    |
    ///     +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
    ///
    /// where:
    ///
    /// ADDRESS         A 32 bit Internet address.
    ///
    /// Hosts that have multiple Internet addresses will have multiple A
    /// records.
    ///
    /// A records cause no additional section processing.  The RDATA section of
    /// an A line in a Zone File is an Internet address expressed as four
    /// decimal numbers separated by dots without any embedded spaces (e.g.,
    /// "10.2.0.52" or "192.0.5.6").
    /// ```
    A(Ipv4Addr),

    /// ```text
    /// -- RFC 1886 -- IPv6 DNS Extensions              December 1995
    ///
    /// 2.2 AAAA data format
    ///
    ///    A 128 bit IPv6 address is encoded in the data portion of an AAAA
    ///    resource record in network byte order (high-order byte first).
    /// ```
    AAAA(Ipv6Addr),

    /// ```text
    /// 2.  The ANAME resource record
    ///
    ///   This document defines the "ANAME" DNS resource record type, with RR
    ///   TYPE value [TBD].
    ///
    /// 2.1.  Presentation and wire format
    ///
    ///   The ANAME presentation format is identical to that of CNAME
    ///   [RFC1033]:
    ///
    ///       owner ttl class ANAME target
    /// ```
    ANAME(Name),

    /// ```text
    /// -- RFC 6844          Certification Authority Authorization     January 2013
    ///
    /// 5.1.  Syntax
    ///
    /// A CAA RR contains a single property entry consisting of a tag-value
    /// pair.  Each tag represents a property of the CAA record.  The value
    /// of a CAA property is that specified in the corresponding value field.
    ///
    /// A domain name MAY have multiple CAA RRs associated with it and a
    /// given property MAY be specified more than once.
    ///
    /// The CAA data field contains one property entry.  A property entry
    /// consists of the following data fields:
    ///
    /// +0-1-2-3-4-5-6-7-|0-1-2-3-4-5-6-7-|
    /// | Flags          | Tag Length = n |
    /// +----------------+----------------+...+---------------+
    /// | Tag char 0     | Tag char 1     |...| Tag char n-1  |
    /// +----------------+----------------+...+---------------+
    /// +----------------+----------------+.....+----------------+
    /// | Value byte 0   | Value byte 1   |.....| Value byte m-1 |
    /// +----------------+----------------+.....+----------------+

    /// Where n is the length specified in the Tag length field and m is the
    /// remaining octets in the Value field (m = d - n - 2) where d is the
    /// length of the RDATA section.
    /// ```
    CAA(CAA),

    /// ```text
    ///   3.3. Standard RRs
    ///
    /// The following RR definitions are expected to occur, at least
    /// potentially, in all classes.  In particular, NS, SOA, CNAME, and PTR
    /// will be used in all classes, and have the same format in all classes.
    /// Because their RDATA format is known, all domain names in the RDATA
    /// section of these RRs may be compressed.
    ///
    /// <domain-name> is a domain name represented as a series of labels, and
    /// terminated by a label with zero length.  <character-string> is a single
    /// length octet followed by that number of characters.  <character-string>
    /// is treated as binary information, and can be up to 256 characters in
    /// length (including the length octet).
    ///
    /// 3.3.1. CNAME RDATA format
    ///
    ///     +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
    ///     /                     CNAME                     /
    ///     /                                               /
    ///     +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
    ///
    /// where:
    ///
    /// CNAME           A <domain-name> which specifies the canonical or primary
    ///                 name for the owner.  The owner name is an alias.
    ///
    /// CNAME RRs cause no additional section processing, but name servers may
    /// choose to restart the query at the canonical name in certain cases.  See
    /// the description of name server logic in [RFC-1034] for details.
    /// ```
    CNAME(Name),

    /// ```text
    /// 2.1.  The CSYNC Resource Record Format
    ///
    /// 2.1.1.  The CSYNC Resource Record Wire Format
    ///
    /// The CSYNC RDATA consists of the following fields:
    ///
    ///                     1 1 1 1 1 1 1 1 1 1 2 2 2 2 2 2 2 2 2 2 3 3
    /// 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
    /// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    /// |                          SOA Serial                           |
    /// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    /// |       Flags                   |            Type Bit Map       /
    /// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    /// /                     Type Bit Map (continued)                  /
    /// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    /// ```
    CSYNC(CSYNC),

    /// ```text
    /// 3.3.2. HINFO RDATA format
    ///
    ///     +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
    ///     /                      CPU                      /
    ///     +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
    ///     /                       OS                      /
    ///     +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
    ///
    /// where:
    ///
    /// CPU             A <character-string> which specifies the CPU type.
    ///
    /// OS              A <character-string> which specifies the operating
    ///                 system type.
    ///
    /// Standard values for CPU and OS can be found in [RFC-1010].
    ///
    /// HINFO records are used to acquire general information about a host.  The
    /// main use is for protocols such as FTP that can use special procedures
    /// when talking between machines or operating systems of the same type.
    /// ```
    ///
    /// `HINFO` is also used by [RFC 8482](https://tools.ietf.org/html/rfc8482)
    HINFO(HINFO),

    /// [RFC draft-ietf-dnsop-svcb-https-03, DNS SVCB and HTTPS RRs](https://datatracker.ietf.org/doc/html/draft-ietf-dnsop-svcb-https-03#section-8)
    ///
    /// ```text
    ///    8.  Using SVCB with HTTPS and HTTP
    ///
    ///    Use of any protocol with SVCB requires a protocol-specific mapping
    ///    specification.  This section specifies the mapping for HTTPS and
    ///    HTTP.
    ///
    ///    To enable special handling for the HTTPS and HTTP use-cases, the
    ///    HTTPS RR type is defined as a SVCB-compatible RR type, specific to
    ///    the https and http schemes.  Clients MUST NOT perform SVCB queries or
    ///    accept SVCB responses for "https" or "http" schemes.
    ///
    ///    The HTTPS RR wire format and presentation format are identical to
    ///    SVCB, and both share the SvcParamKey registry.  SVCB semantics apply
    ///    equally to HTTPS RRs unless specified otherwise.  The presentation
    ///    format of the record is:
    ///
    ///    Name TTL IN HTTPS SvcPriority TargetName SvcParams
    /// ```
    HTTPS(SVCB),

    /// ```text
    /// 3.3.9. MX RDATA format
    ///
    ///     +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
    ///     |                  PREFERENCE                   |
    ///     +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
    ///     /                   EXCHANGE                    /
    ///     /                                               /
    ///     +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
    ///
    /// where:
    ///
    /// PREFERENCE      A 16 bit integer which specifies the preference given to
    ///                 this RR among others at the same owner.  Lower values
    ///                 are preferred.
    ///
    /// EXCHANGE        A <domain-name> which specifies a host willing to act as
    ///                 a mail exchange for the owner name.
    ///
    /// MX records cause type A additional section processing for the host
    /// specified by EXCHANGE.  The use of MX RRs is explained in detail in
    /// [RFC-974].
    /// ```
    MX(MX),

    /// [RFC 3403 DDDS DNS Database, October 2002](https://tools.ietf.org/html/rfc3403#section-4)
    ///
    /// ```text
    /// 4.1 Packet Format
    ///
    ///   The packet format of the NAPTR RR is given below.  The DNS type code
    ///   for NAPTR is 35.
    ///
    ///      The packet format for the NAPTR record is as follows
    ///                                       1  1  1  1  1  1
    ///         0  1  2  3  4  5  6  7  8  9  0  1  2  3  4  5
    ///       +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
    ///       |                     ORDER                     |
    ///       +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
    ///       |                   PREFERENCE                  |
    ///       +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
    ///       /                     FLAGS                     /
    ///       +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
    ///       /                   SERVICES                    /
    ///       +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
    ///       /                    REGEXP                     /
    ///       +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
    ///       /                  REPLACEMENT                  /
    ///       /                                               /
    ///       +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
    ///
    ///   <character-string> and <domain-name> as used here are defined in RFC
    ///   1035 [7].
    ///
    ///   ORDER
    ///      A 16-bit unsigned integer specifying the order in which the NAPTR
    ///      records MUST be processed in order to accurately represent the
    ///      ordered list of Rules.  The ordering is from lowest to highest.
    ///      If two records have the same order value then they are considered
    ///      to be the same rule and should be selected based on the
    ///      combination of the Preference values and Services offered.
    ///
    ///   PREFERENCE
    ///      Although it is called "preference" in deference to DNS
    ///      terminology, this field is equivalent to the Priority value in the
    ///      DDDS Algorithm.  It is a 16-bit unsigned integer that specifies
    ///      the order in which NAPTR records with equal Order values SHOULD be
    ///      processed, low numbers being processed before high numbers.  This
    ///      is similar to the preference field in an MX record, and is used so
    ///      domain administrators can direct clients towards more capable
    ///      hosts or lighter weight protocols.  A client MAY look at records
    ///      with higher preference values if it has a good reason to do so
    ///      such as not supporting some protocol or service very well.
    ///
    ///      The important difference between Order and Preference is that once
    ///      a match is found the client MUST NOT consider records with a
    ///      different Order but they MAY process records with the same Order
    ///      but different Preferences.  The only exception to this is noted in
    ///      the second important Note in the DDDS algorithm specification
    ///      concerning allowing clients to use more complex Service
    ///      determination between steps 3 and 4 in the algorithm.  Preference
    ///      is used to give communicate a higher quality of service to rules
    ///      that are considered the same from an authority standpoint but not
    ///      from a simple load balancing standpoint.
    ///
    ///      It is important to note that DNS contains several load balancing
    ///      mechanisms and if load balancing among otherwise equal services
    ///      should be needed then methods such as SRV records or multiple A
    ///      records should be utilized to accomplish load balancing.
    ///
    ///   FLAGS
    ///      A <character-string> containing flags to control aspects of the
    ///      rewriting and interpretation of the fields in the record.  Flags
    ///      are single characters from the set A-Z and 0-9.  The case of the
    ///      alphabetic characters is not significant.  The field can be empty.
    ///
    ///      It is up to the Application specifying how it is using this
    ///      Database to define the Flags in this field.  It must define which
    ///      ones are terminal and which ones are not.
    ///
    ///   SERVICES
    ///      A <character-string> that specifies the Service Parameters
    ///      applicable to this this delegation path.  It is up to the
    ///      Application Specification to specify the values found in this
    ///      field.
    ///
    ///   REGEXP
    ///      A <character-string> containing a substitution expression that is
    ///      applied to the original string held by the client in order to
    ///      construct the next domain name to lookup.  See the DDDS Algorithm
    ///      specification for the syntax of this field.
    ///
    ///      As stated in the DDDS algorithm, The regular expressions MUST NOT
    ///      be used in a cumulative fashion, that is, they should only be
    ///      applied to the original string held by the client, never to the
    ///      domain name produced by a previous NAPTR rewrite.  The latter is
    ///      tempting in some applications but experience has shown such use to
    ///      be extremely fault sensitive, very error prone, and extremely
    ///      difficult to debug.
    ///
    ///   REPLACEMENT
    ///      A <domain-name> which is the next domain-name to query for
    ///      depending on the potential values found in the flags field.  This
    ///      field is used when the regular expression is a simple replacement
    ///      operation.  Any value in this field MUST be a fully qualified
    ///      domain-name.  Name compression is not to be used for this field.
    ///
    ///      This field and the REGEXP field together make up the Substitution
    ///      Expression in the DDDS Algorithm.  It is simply a historical
    ///      optimization specifically for DNS compression that this field
    ///      exists.  The fields are also mutually exclusive.  If a record is
    ///      returned that has values for both fields then it is considered to
    ///      be in error and SHOULD be either ignored or an error returned.
    /// ```
    NAPTR(NAPTR),

    /// ```text
    /// 3.3.10. NULL RDATA format (EXPERIMENTAL)
    ///
    ///     +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
    ///     /                  <anything>                   /
    ///     /                                               /
    ///     +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
    ///
    /// Anything at all may be in the RDATA field so long as it is 65535 octets
    /// or less.
    ///
    /// NULL records cause no additional section processing.  NULL RRs are not
    /// allowed in Zone Files.  NULLs are used as placeholders in some
    /// experimental extensions of the DNS.
    /// ```
    NULL(NULL),

    /// ```text
    /// 3.3.11. NS RDATA format
    ///
    ///     +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
    ///     /                   NSDNAME                     /
    ///     /                                               /
    ///     +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
    ///
    /// where:
    ///
    /// NSDNAME         A <domain-name> which specifies a host which should be
    ///                 authoritative for the specified class and domain.
    ///
    /// NS records cause both the usual additional section processing to locate
    /// a type A record, and, when used in a referral, a special search of the
    /// zone in which they reside for glue information.
    ///
    /// The NS RR states that the named host should be expected to have a zone
    /// starting at owner name of the specified class.  Note that the class may
    /// not indicate the protocol family which should be used to communicate
    /// with the host, although it is typically a strong hint.  For example,
    /// hosts which are name servers for either Internet (IN) or Hesiod (HS)
    /// class information are normally queried using IN class protocols.
    /// ```
    NS(Name),

    /// [RFC 7929](https://tools.ietf.org/html/rfc7929#section-2.1)
    ///
    /// ```text
    /// The RDATA portion of an OPENPGPKEY resource record contains a single
    /// value consisting of a Transferable Public Key formatted as specified
    /// in [RFC4880].
    /// ```
    OPENPGPKEY(OPENPGPKEY),

    /// ```text
    /// RFC 6891                   EDNS(0) Extensions                 April 2013
    /// 6.1.2.  Wire Format
    ///
    ///        +------------+--------------+------------------------------+
    ///        | Field Name | Field Type   | Description                  |
    ///        +------------+--------------+------------------------------+
    ///        | NAME       | domain name  | MUST be 0 (root domain)      |
    ///        | TYPE       | u_int16_t    | OPT (41)                     |
    ///        | CLASS      | u_int16_t    | requestor's UDP payload size |
    ///        | TTL        | u_int32_t    | extended RCODE and flags     |
    ///        | RDLEN      | u_int16_t    | length of all RDATA          |
    ///        | RDATA      | octet stream | {attribute,value} pairs      |
    ///        +------------+--------------+------------------------------+
    ///
    /// The variable part of an OPT RR may contain zero or more options in
    ///    the RDATA.  Each option MUST be treated as a bit field.  Each option
    ///    is encoded as:
    ///
    ///                   +0 (MSB)                            +1 (LSB)
    ///        +---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+
    ///     0: |                          OPTION-CODE                          |
    ///        +---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+
    ///     2: |                         OPTION-LENGTH                         |
    ///        +---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+
    ///     4: |                                                               |
    ///        /                          OPTION-DATA                          /
    ///        /                                                               /
    ///        +---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+
    /// ```
    OPT(OPT),

    /// ```text
    /// 3.3.12. PTR RDATA format
    ///
    ///     +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
    ///     /                   PTRDNAME                    /
    ///     +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
    ///
    /// where:
    ///
    /// PTRDNAME        A <domain-name> which points to some location in the
    ///                 domain name space.
    ///
    /// PTR records cause no additional section processing.  These RRs are used
    /// in special domains to point to some other location in the domain space.
    /// These records are simple data, and don't imply any special processing
    /// similar to that performed by CNAME, which identifies aliases.  See the
    /// description of the IN-ADDR.ARPA domain for an example.
    /// ```
    PTR(Name),

    /// ```text
    /// 3.3.13. SOA RDATA format
    ///
    ///     +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
    ///     /                     MNAME                     /
    ///     /                                               /
    ///     +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
    ///     /                     RNAME                     /
    ///     +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
    ///     |                    SERIAL                     |
    ///     |                                               |
    ///     +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
    ///     |                    REFRESH                    |
    ///     |                                               |
    ///     +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
    ///     |                     RETRY                     |
    ///     |                                               |
    ///     +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
    ///     |                    EXPIRE                     |
    ///     |                                               |
    ///     +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
    ///     |                    MINIMUM                    |
    ///     |                                               |
    ///     +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
    ///
    /// where:
    ///
    /// MNAME           The <domain-name> of the name server that was the
    ///                 original or primary source of data for this zone.
    ///
    /// RNAME           A <domain-name> which specifies the mailbox of the
    ///                 person responsible for this zone.
    ///
    /// SERIAL          The unsigned 32 bit version number of the original copy
    ///                 of the zone.  Zone transfers preserve this value.  This
    ///                 value wraps and should be compared using sequence space
    ///                 arithmetic.
    ///
    /// REFRESH         A 32 bit time interval before the zone should be
    ///                 refreshed.
    ///
    /// RETRY           A 32 bit time interval that should elapse before a
    ///                 failed refresh should be retried.
    ///
    /// EXPIRE          A 32 bit time value that specifies the upper limit on
    ///                 the time interval that can elapse before the zone is no
    ///                 longer authoritative.
    ///
    /// MINIMUM         The unsigned 32 bit minimum TTL field that should be
    ///                 exported with any RR from this zone.
    ///
    /// SOA records cause no additional section processing.
    ///
    /// All times are in units of seconds.
    ///
    /// Most of these fields are pertinent only for name server maintenance
    /// operations.  However, MINIMUM is used in all query operations that
    /// retrieve RRs from a zone.  Whenever a RR is sent in a response to a
    /// query, the TTL field is set to the maximum of the TTL field from the RR
    /// and the MINIMUM field in the appropriate SOA.  Thus MINIMUM is a lower
    /// bound on the TTL field for all RRs in a zone.  Note that this use of
    /// MINIMUM should occur when the RRs are copied into the response and not
    /// when the zone is loaded from a Zone File or via a zone transfer.  The
    /// reason for this provision is to allow future dynamic update facilities to
    /// change the SOA RR with known semantics.
    /// ```
    SOA(SOA),

    /// ```text
    /// RFC 2782                       DNS SRV RR                  February 2000
    ///
    /// The format of the SRV RR
    ///
    ///  _Service._Proto.Name TTL Class SRV Priority Weight Port Target
    /// ```
    SRV(SRV),

    /// [RFC 4255](https://tools.ietf.org/html/rfc4255#section-3.1)
    ///
    /// ```text
    /// 3.1.  The SSHFP RDATA Format
    ///
    ///    The RDATA for a SSHFP RR consists of an algorithm number, fingerprint
    ///    type and the fingerprint of the public host key.
    ///
    ///        1 1 1 1 1 1 1 1 1 1 2 2 2 2 2 2 2 2 2 2 3 3
    ///        0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
    ///        +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    ///        |   algorithm   |    fp type    |                               /
    ///        +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+                               /
    ///        /                                                               /
    ///        /                          fingerprint                          /
    ///        /                                                               /
    ///        +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    ///
    /// 3.1.1.  Algorithm Number Specification
    ///
    ///    This algorithm number octet describes the algorithm of the public
    ///    key.  The following values are assigned:
    ///
    ///           Value    Algorithm name
    ///           -----    --------------
    ///           0        reserved
    ///           1        RSA
    ///           2        DSS
    ///
    ///    Reserving other types requires IETF consensus [4].
    ///
    /// 3.1.2.  Fingerprint Type Specification
    ///
    ///    The fingerprint type octet describes the message-digest algorithm
    ///    used to calculate the fingerprint of the public key.  The following
    ///    values are assigned:
    ///
    ///           Value    Fingerprint type
    ///           -----    ----------------
    ///           0        reserved
    ///           1        SHA-1
    ///
    ///    Reserving other types requires IETF consensus [4].
    ///
    ///    For interoperability reasons, as few fingerprint types as possible
    ///    should be reserved.  The only reason to reserve additional types is
    ///    to increase security.
    ///
    /// 3.1.3.  Fingerprint
    ///
    ///    The fingerprint is calculated over the public key blob as described
    ///    in [7].
    ///
    ///    The message-digest algorithm is presumed to produce an opaque octet
    ///    string output, which is placed as-is in the RDATA fingerprint field.
    /// ```
    ///
    /// The algorithm and fingerprint type values have been updated in
    /// [RFC 6594](https://tools.ietf.org/html/rfc6594) and
    /// [RFC 7479](https://tools.ietf.org/html/rfc7479).
    SSHFP(SSHFP),

    /// [RFC draft-ietf-dnsop-svcb-https-03, DNS SVCB and HTTPS RRs](https://datatracker.ietf.org/doc/html/draft-ietf-dnsop-svcb-https-03#section-2)
    ///
    /// ```text
    ///    2.  The SVCB record type
    ///
    ///   The SVCB DNS resource record (RR) type (RR type 64) is used to locate
    ///   alternative endpoints for a service.
    ///
    ///   The algorithm for resolving SVCB records and associated address
    ///   records is specified in Section 3.
    ///
    ///   Other SVCB-compatible resource record types can also be defined as-
    ///   needed.  In particular, the HTTPS RR (RR type 65) provides special
    ///   handling for the case of "https" origins as described in Section 8.
    ///
    ///   SVCB RRs are extensible by a list of SvcParams, which are pairs
    ///   consisting of a SvcParamKey and a SvcParamValue.  Each SvcParamKey
    ///   has a presentation name and a registered number.  Values are in a
    ///   format specific to the SvcParamKey.  Their definition should specify
    ///   both their presentation format and wire encoding (e.g., domain names,
    ///   binary data, or numeric values).  The initial SvcParamKeys and
    ///   formats are defined in Section 6.
    /// ```
    SVCB(SVCB),

    /// [RFC 6698, DNS-Based Authentication for TLS](https://tools.ietf.org/html/rfc6698#section-2.1)
    ///
    /// ```text
    ///                         1 1 1 1 1 1 1 1 1 1 2 2 2 2 2 2 2 2 2 2 3 3
    ///     0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
    ///    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    ///    |  Cert. Usage  |   Selector    | Matching Type |               /
    ///    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+               /
    ///    /                                                               /
    ///    /                 Certificate Association Data                  /
    ///    /                                                               /
    ///    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    /// ```
    TLSA(TLSA),

    /// ```text
    /// 3.3.14. TXT RDATA format
    ///
    ///     +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
    ///     /                   TXT-DATA                    /
    ///     +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
    ///
    /// where:
    ///
    /// TXT-DATA        One or more <character-string>s.
    ///
    /// TXT RRs are used to hold descriptive text.  The semantics of the text
    /// depends on the domain where it is found.
    /// ```
    TXT(TXT),

    /// A DNSSEC- or SIG(0)- specific record. See `DNSSECRData` for details.
    ///
    /// These types are in `DNSSECRData` to make them easy to disable when
    /// crypto functionality isn't needed.
    #[cfg(feature = "dnssec")]
    #[cfg_attr(docsrs, doc(cfg(feature = "dnssec")))]
    DNSSEC(DNSSECRData),

    /// Unknown RecordData is for record types not supported by Trust-DNS
    Unknown {
        /// RecordType code
        code: u16,
        /// RData associated to the record
        rdata: NULL,
    },

    /// This corresponds to a record type of 0, unspecified
    #[deprecated(note = "Use None for the RData in the resource record instead")]
    ZERO,
}

impl RData {
    fn to_bytes(&self) -> Vec<u8> {
        let mut buf: Vec<u8> = Vec::new();
        {
            let mut encoder: BinEncoder<'_> = BinEncoder::new(&mut buf);
            self.emit(&mut encoder).unwrap_or_else(|_| {
                warn!("could not encode RDATA: {:?}", self);
            });
        }
        buf
    }

    /// Read the RData from the given Decoder
    pub fn read(
        decoder: &mut BinDecoder<'_>,
        record_type: RecordType,
        rdata_length: Restrict<u16>,
    ) -> ProtoResult<Self> {
        let start_idx = decoder.index();

        let result = match record_type {
            RecordType::A => {
                trace!("reading A");
                rdata::a::read(decoder).map(Self::A)
            }
            RecordType::AAAA => {
                trace!("reading AAAA");
                rdata::aaaa::read(decoder).map(Self::AAAA)
            }
            RecordType::ANAME => {
                trace!("reading ANAME");
                rdata::name::read(decoder).map(Self::ANAME)
            }
            rt @ RecordType::ANY | rt @ RecordType::AXFR | rt @ RecordType::IXFR => {
                return Err(ProtoErrorKind::UnknownRecordTypeValue(rt.into()).into());
            }
            RecordType::CAA => {
                trace!("reading CAA");
                rdata::caa::read(decoder, rdata_length).map(Self::CAA)
            }
            RecordType::CNAME => {
                trace!("reading CNAME");
                rdata::name::read(decoder).map(Self::CNAME)
            }
            RecordType::CSYNC => {
                trace!("reading CSYNC");
                rdata::csync::read(decoder, rdata_length).map(Self::CSYNC)
            }
            RecordType::HINFO => {
                trace!("reading HINFO");
                rdata::hinfo::read(decoder).map(Self::HINFO)
            }
            RecordType::HTTPS => {
                trace!("reading HTTPS");
                rdata::svcb::read(decoder, rdata_length).map(Self::HTTPS)
            }
            RecordType::ZERO => {
                trace!("reading EMPTY");
                // we should never get here, since ZERO should be 0 length, and None in the Record.
                //   this invariant is verified below, and the decoding will fail with an err.
                #[allow(deprecated)]
                Ok(Self::ZERO)
            }
            RecordType::MX => {
                trace!("reading MX");
                rdata::mx::read(decoder).map(Self::MX)
            }
            RecordType::NAPTR => {
                trace!("reading NAPTR");
                rdata::naptr::read(decoder).map(Self::NAPTR)
            }
            RecordType::NULL => {
                trace!("reading NULL");
                rdata::null::read(decoder, rdata_length).map(Self::NULL)
            }
            RecordType::NS => {
                trace!("reading NS");
                rdata::name::read(decoder).map(Self::NS)
            }
            RecordType::OPENPGPKEY => {
                trace!("reading OPENPGPKEY");
                rdata::openpgpkey::read(decoder, rdata_length).map(Self::OPENPGPKEY)
            }
            RecordType::OPT => {
                trace!("reading OPT");
                rdata::opt::read(decoder, rdata_length).map(Self::OPT)
            }
            RecordType::PTR => {
                trace!("reading PTR");
                rdata::name::read(decoder).map(Self::PTR)
            }
            RecordType::SOA => {
                trace!("reading SOA");
                rdata::soa::read(decoder).map(Self::SOA)
            }
            RecordType::SRV => {
                trace!("reading SRV");
                rdata::srv::read(decoder).map(Self::SRV)
            }
            RecordType::SSHFP => {
                trace!("reading SSHFP");
                rdata::sshfp::read(decoder, rdata_length).map(Self::SSHFP)
            }
            RecordType::SVCB => {
                trace!("reading SVCB");
                rdata::svcb::read(decoder, rdata_length).map(Self::SVCB)
            }
            RecordType::TLSA => {
                trace!("reading TLSA");
                rdata::tlsa::read(decoder, rdata_length).map(Self::TLSA)
            }
            RecordType::TXT => {
                trace!("reading TXT");
                rdata::txt::read(decoder, rdata_length).map(Self::TXT)
            }
            #[cfg(feature = "dnssec")]
            r if r.is_dnssec() => {
                DNSSECRData::read(decoder, record_type, rdata_length).map(Self::DNSSEC)
            }
            record_type => {
                trace!("reading Unknown record: {}", record_type);
                rdata::null::read(decoder, rdata_length).map(|rdata| Self::Unknown {
                    code: record_type.into(),
                    rdata,
                })
            }
        };

        // we should have read rdata_length, but we did not
        let read = decoder.index() - start_idx;
        rdata_length
            .map(|u| u as usize)
            .verify_unwrap(|rdata_length| read == *rdata_length)
            .map_err(|rdata_length| {
                ProtoError::from(ProtoErrorKind::IncorrectRDataLengthRead {
                    read,
                    len: rdata_length,
                })
            })?;

        result
    }

    /// [RFC 4034](https://tools.ietf.org/html/rfc4034#section-6), DNSSEC Resource Records, March 2005
    ///
    /// ```text
    /// 6.2.  Canonical RR Form
    ///
    ///    For the purposes of DNS security, the canonical form of an RR is the
    ///    wire format of the RR where:
    ///
    ///    ...
    ///
    ///    3.  if the type of the RR is NS, MD, MF, CNAME, SOA, MB, MG, MR, PTR,
    ///        HINFO, MINFO, MX, HINFO, RP, AFSDB, RT, SIG, PX, NXT, NAPTR, KX,
    ///        SRV, DNAME, A6, RRSIG, or (rfc6840 removes NSEC), all uppercase
    ///        US-ASCII letters in the DNS names contained within the RDATA are replaced
    ///        by the corresponding lowercase US-ASCII letters;
    /// ```
    ///
    /// Canonical name form for all non-1035 records:
    ///   [RFC 3579](https://tools.ietf.org/html/rfc3597)
    /// ```text
    ///  4.  Domain Name Compression
    ///
    ///   RRs containing compression pointers in the RDATA part cannot be
    ///   treated transparently, as the compression pointers are only
    ///   meaningful within the context of a DNS message.  Transparently
    ///   copying the RDATA into a new DNS message would cause the compression
    ///   pointers to point at the corresponding location in the new message,
    ///   which now contains unrelated data.  This would cause the compressed
    ///   name to be corrupted.
    ///
    ///   To avoid such corruption, servers MUST NOT compress domain names
    ///   embedded in the RDATA of types that are class-specific or not well-
    ///   known.  This requirement was stated in [RFC1123] without defining the
    ///   term "well-known"; it is hereby specified that only the RR types
    ///   defined in [RFC1035] are to be considered "well-known".
    ///
    ///   The specifications of a few existing RR types have explicitly allowed
    ///   compression contrary to this specification: [RFC2163] specified that
    ///   compression applies to the PX RR, and [RFC2535] allowed compression
    ///   in SIG RRs and NXT RRs records.  Since this specification disallows
    ///   compression in these cases, it is an update to [RFC2163] (section 4)
    ///   and [RFC2535] (sections 4.1.7 and 5.2).
    ///
    ///   Receiving servers MUST decompress domain names in RRs of well-known
    ///   type, and SHOULD also decompress RRs of type RP, AFSDB, RT, SIG, PX,
    ///   NXT, NAPTR, and SRV (although the current specification of the SRV RR
    ///   in [RFC2782] prohibits compression, [RFC2052] mandated it, and some
    ///   servers following that earlier specification are still in use).
    ///
    ///   Future specifications for new RR types that contain domain names
    ///   within their RDATA MUST NOT allow the use of name compression for
    ///   those names, and SHOULD explicitly state that the embedded domain
    ///   names MUST NOT be compressed.
    ///
    ///   As noted in [RFC1123], the owner name of an RR is always eligible for
    ///   compression.
    ///
    ///   ...
    ///   As a courtesy to implementors, it is hereby noted that the complete
    ///    set of such previously published RR types that contain embedded
    ///    domain names, and whose DNSSEC canonical form therefore involves
    ///   downcasing according to the DNS rules for character comparisons,
    ///   consists of the RR types NS, MD, MF, CNAME, SOA, MB, MG, MR, PTR,
    ///   HINFO, MINFO, MX, HINFO, RP, AFSDB, RT, SIG, PX, NXT, NAPTR, KX, SRV,
    ///   DNAME, and A6.
    ///   ...
    /// ```
    pub fn emit(&self, encoder: &mut BinEncoder<'_>) -> ProtoResult<()> {
        match *self {
            RData::A(address) => rdata::a::emit(encoder, address),
            RData::AAAA(ref address) => rdata::aaaa::emit(encoder, address),
            RData::ANAME(ref name) => {
                encoder.with_canonical_names(|encoder| rdata::name::emit(encoder, name))
            }
            RData::CAA(ref caa) => {
                encoder.with_canonical_names(|encoder| rdata::caa::emit(encoder, caa))
            }
            // to_lowercase for rfc4034 and rfc6840
            RData::CNAME(ref name) | RData::NS(ref name) | RData::PTR(ref name) => {
                rdata::name::emit(encoder, name)
            }
            RData::CSYNC(ref csync) => rdata::csync::emit(encoder, csync),
            RData::HINFO(ref hinfo) => rdata::hinfo::emit(encoder, hinfo),
            RData::HTTPS(ref svcb) => rdata::svcb::emit(encoder, svcb),
            RData::ZERO => Ok(()),
            // to_lowercase for rfc4034 and rfc6840
            RData::MX(ref mx) => rdata::mx::emit(encoder, mx),
            RData::NAPTR(ref naptr) => {
                encoder.with_canonical_names(|encoder| rdata::naptr::emit(encoder, naptr))
            }
            RData::NULL(ref null) => rdata::null::emit(encoder, null),
            RData::OPENPGPKEY(ref openpgpkey) => {
                encoder.with_canonical_names(|encoder| rdata::openpgpkey::emit(encoder, openpgpkey))
            }
            RData::OPT(ref opt) => rdata::opt::emit(encoder, opt),
            // to_lowercase for rfc4034 and rfc6840
            RData::SOA(ref soa) => rdata::soa::emit(encoder, soa),
            // to_lowercase for rfc4034 and rfc6840
            RData::SRV(ref srv) => {
                encoder.with_canonical_names(|encoder| rdata::srv::emit(encoder, srv))
            }
            RData::SSHFP(ref sshfp) => {
                encoder.with_canonical_names(|encoder| rdata::sshfp::emit(encoder, sshfp))
            }
            RData::SVCB(ref svcb) => rdata::svcb::emit(encoder, svcb),
            RData::TLSA(ref tlsa) => {
                encoder.with_canonical_names(|encoder| rdata::tlsa::emit(encoder, tlsa))
            }
            RData::TXT(ref txt) => rdata::txt::emit(encoder, txt),
            #[cfg(feature = "dnssec")]
            RData::DNSSEC(ref rdata) => encoder.with_canonical_names(|encoder| rdata.emit(encoder)),
            RData::Unknown { ref rdata, .. } => rdata::null::emit(encoder, rdata),
        }
    }

    /// Converts this to a Recordtype
    pub fn to_record_type(&self) -> RecordType {
        match *self {
            RData::A(..) => RecordType::A,
            RData::AAAA(..) => RecordType::AAAA,
            RData::ANAME(..) => RecordType::ANAME,
            RData::CAA(..) => RecordType::CAA,
            RData::CNAME(..) => RecordType::CNAME,
            RData::CSYNC(..) => RecordType::CSYNC,
            RData::HINFO(..) => RecordType::HINFO,
            RData::HTTPS(..) => RecordType::HTTPS,
            RData::MX(..) => RecordType::MX,
            RData::NAPTR(..) => RecordType::NAPTR,
            RData::NS(..) => RecordType::NS,
            RData::NULL(..) => RecordType::NULL,
            RData::OPENPGPKEY(..) => RecordType::OPENPGPKEY,
            RData::OPT(..) => RecordType::OPT,
            RData::PTR(..) => RecordType::PTR,
            RData::SOA(..) => RecordType::SOA,
            RData::SRV(..) => RecordType::SRV,
            RData::SSHFP(..) => RecordType::SSHFP,
            RData::SVCB(..) => RecordType::SVCB,
            RData::TLSA(..) => RecordType::TLSA,
            RData::TXT(..) => RecordType::TXT,
            #[cfg(feature = "dnssec")]
            RData::DNSSEC(ref rdata) => DNSSECRData::to_record_type(rdata),
            RData::Unknown { code, .. } => RecordType::Unknown(code),
            RData::ZERO => RecordType::ZERO,
        }
    }

    /// If this is an A or AAAA record type, then an IpAddr will be returned
    pub fn to_ip_addr(&self) -> Option<IpAddr> {
        match *self {
            RData::A(a) => Some(IpAddr::from(a)),
            RData::AAAA(aaaa) => Some(IpAddr::from(aaaa)),
            _ => None,
        }
    }
}

impl fmt::Display for RData {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> Result<(), fmt::Error> {
        fn w<D: fmt::Display>(f: &mut fmt::Formatter<'_>, d: D) -> Result<(), fmt::Error> {
            write!(f, "{rdata}", rdata = d)
        }

        match *self {
            RData::A(address) => w(f, address),
            RData::AAAA(ref address) => w(f, address),
            RData::ANAME(ref name) => w(f, name),
            RData::CAA(ref caa) => w(f, caa),
            // to_lowercase for rfc4034 and rfc6840
            RData::CNAME(ref name) | RData::NS(ref name) | RData::PTR(ref name) => w(f, name),
            RData::CSYNC(ref csync) => w(f, csync),
            RData::HINFO(ref hinfo) => w(f, hinfo),
            RData::HTTPS(ref svcb) => w(f, svcb),
            RData::ZERO => Ok(()),
            // to_lowercase for rfc4034 and rfc6840
            RData::MX(ref mx) => w(f, mx),
            RData::NAPTR(ref naptr) => w(f, naptr),
            RData::NULL(ref null) => w(f, null),
            RData::OPENPGPKEY(ref openpgpkey) => w(f, openpgpkey),
            // Opt has no display representation
            RData::OPT(_) => Err(fmt::Error),
            // to_lowercase for rfc4034 and rfc6840
            RData::SOA(ref soa) => w(f, soa),
            // to_lowercase for rfc4034 and rfc6840
            RData::SRV(ref srv) => w(f, srv),
            RData::SSHFP(ref sshfp) => w(f, sshfp),
            RData::SVCB(ref svcb) => w(f, svcb),
            RData::TLSA(ref tlsa) => w(f, tlsa),
            RData::TXT(ref txt) => w(f, txt),
            #[cfg(feature = "dnssec")]
            RData::DNSSEC(ref rdata) => w(f, rdata),
            RData::Unknown { ref rdata, .. } => w(f, rdata),
        }
    }
}

impl PartialOrd<Self> for RData {
    fn partial_cmp(&self, other: &Self) -> Option<Ordering> {
        Some(self.cmp(other))
    }
}

impl Ord for RData {
    // RFC 4034                DNSSEC Resource Records               March 2005
    //
    // 6.3.  Canonical RR Ordering within an RRset
    //
    //    For the purposes of DNS security, RRs with the same owner name,
    //    class, and type are sorted by treating the RDATA portion of the
    //    canonical form of each RR as a left-justified unsigned octet sequence
    //    in which the absence of an octet sorts before a zero octet.
    //
    //    [RFC2181] specifies that an RRset is not allowed to contain duplicate
    //    records (multiple RRs with the same owner name, class, type, and
    //    RDATA).  Therefore, if an implementation detects duplicate RRs when
    //    putting the RRset in canonical form, it MUST treat this as a protocol
    //    error.  If the implementation chooses to handle this protocol error
    //    in the spirit of the robustness principle (being liberal in what it
    //    accepts), it MUST remove all but one of the duplicate RR(s) for the
    //    purposes of calculating the canonical form of the RRset.
    fn cmp(&self, other: &Self) -> Ordering {
        // TODO: how about we just store the bytes with the decoded data?
        //  the decoded data is useful for queries, the encoded data is needed for transfers, signing
        //  and ordering.
        self.to_bytes().cmp(&other.to_bytes())
    }
}

#[cfg(test)]
mod tests {
    #![allow(clippy::dbg_macro, clippy::print_stdout)]

    use std::net::Ipv4Addr;
    use std::net::Ipv6Addr;
    use std::str::FromStr;

    use super::*;
    use crate::rr::domain::Name;
    use crate::rr::rdata::{MX, SOA, SRV, TXT};
    use crate::serialize::binary::bin_tests::test_emit_data_set;
    #[allow(clippy::useless_attribute)]
    #[allow(unused)]
    use crate::serialize::binary::*;

    fn get_data() -> Vec<(RData, Vec<u8>)> {
        vec![
            (
                RData::CNAME(Name::from_str("www.example.com").unwrap()),
                vec![
                    3, b'w', b'w', b'w', 7, b'e', b'x', b'a', b'm', b'p', b'l', b'e', 3, b'c',
                    b'o', b'm', 0,
                ],
            ),
            (
                RData::MX(MX::new(256, Name::from_str("n").unwrap())),
                vec![1, 0, 1, b'n', 0],
            ),
            (
                RData::NS(Name::from_str("www.example.com").unwrap()),
                vec![
                    3, b'w', b'w', b'w', 7, b'e', b'x', b'a', b'm', b'p', b'l', b'e', 3, b'c',
                    b'o', b'm', 0,
                ],
            ),
            (
                RData::PTR(Name::from_str("www.example.com").unwrap()),
                vec![
                    3, b'w', b'w', b'w', 7, b'e', b'x', b'a', b'm', b'p', b'l', b'e', 3, b'c',
                    b'o', b'm', 0,
                ],
            ),
            (
                RData::SOA(SOA::new(
                    Name::from_str("www.example.com").unwrap(),
                    Name::from_str("xxx.example.com").unwrap(),
                    u32::max_value(),
                    -1,
                    -1,
                    -1,
                    u32::max_value(),
                )),
                vec![
                    3, b'w', b'w', b'w', 7, b'e', b'x', b'a', b'm', b'p', b'l', b'e', 3, b'c',
                    b'o', b'm', 0, 3, b'x', b'x', b'x', 0xC0, 0x04, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
                    0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
                    0xFF, 0xFF,
                ],
            ),
            (
                RData::TXT(TXT::new(vec![
                    "abcdef".to_string(),
                    "ghi".to_string(),
                    "".to_string(),
                    "j".to_string(),
                ])),
                vec![
                    6, b'a', b'b', b'c', b'd', b'e', b'f', 3, b'g', b'h', b'i', 0, 1, b'j',
                ],
            ),
            (
                RData::A(Ipv4Addr::from_str("0.0.0.0").unwrap()),
                vec![0, 0, 0, 0],
            ),
            (
                RData::AAAA(Ipv6Addr::from_str("::").unwrap()),
                vec![0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0],
            ),
            (
                RData::SRV(SRV::new(
                    1,
                    2,
                    3,
                    Name::from_str("www.example.com").unwrap(),
                )),
                vec![
                    0x00, 0x01, 0x00, 0x02, 0x00, 0x03, 3, b'w', b'w', b'w', 7, b'e', b'x', b'a',
                    b'm', b'p', b'l', b'e', 3, b'c', b'o', b'm', 0,
                ],
            ),
            (
                RData::HINFO(HINFO::new("cpu".to_string(), "os".to_string())),
                vec![3, b'c', b'p', b'u', 2, b'o', b's'],
            ),
        ]
    }

    // TODO this test kinda sucks, shows the problem with not storing the binary parts
    #[test]
    fn test_order() {
        let ordered: Vec<RData> = vec![
            RData::A(Ipv4Addr::from_str("0.0.0.0").unwrap()),
            RData::AAAA(Ipv6Addr::from_str("::").unwrap()),
            RData::SRV(SRV::new(
                1,
                2,
                3,
                Name::from_str("www.example.com").unwrap(),
            )),
            RData::MX(MX::new(256, Name::from_str("n").unwrap())),
            RData::CNAME(Name::from_str("www.example.com").unwrap()),
            RData::PTR(Name::from_str("www.example.com").unwrap()),
            RData::NS(Name::from_str("www.example.com").unwrap()),
            RData::SOA(SOA::new(
                Name::from_str("www.example.com").unwrap(),
                Name::from_str("xxx.example.com").unwrap(),
                u32::max_value(),
                -1,
                -1,
                -1,
                u32::max_value(),
            )),
            RData::TXT(TXT::new(vec![
                "abcdef".to_string(),
                "ghi".to_string(),
                "".to_string(),
                "j".to_string(),
            ])),
        ];
        let mut unordered = vec![
            RData::CNAME(Name::from_str("www.example.com").unwrap()),
            RData::MX(MX::new(256, Name::from_str("n").unwrap())),
            RData::PTR(Name::from_str("www.example.com").unwrap()),
            RData::NS(Name::from_str("www.example.com").unwrap()),
            RData::SOA(SOA::new(
                Name::from_str("www.example.com").unwrap(),
                Name::from_str("xxx.example.com").unwrap(),
                u32::max_value(),
                -1,
                -1,
                -1,
                u32::max_value(),
            )),
            RData::TXT(TXT::new(vec![
                "abcdef".to_string(),
                "ghi".to_string(),
                "".to_string(),
                "j".to_string(),
            ])),
            RData::A(Ipv4Addr::from_str("0.0.0.0").unwrap()),
            RData::AAAA(Ipv6Addr::from_str("::").unwrap()),
            RData::SRV(SRV::new(
                1,
                2,
                3,
                Name::from_str("www.example.com").unwrap(),
            )),
        ];

        unordered.sort();
        assert_eq!(ordered, unordered);
    }

    #[test]
    fn test_read() {
        for (test_pass, (expect, binary)) in get_data().into_iter().enumerate() {
            println!("test {}: {:?}", test_pass, binary);
            let length = binary.len() as u16; // pre exclusive borrow
            let mut decoder = BinDecoder::new(&binary);

            assert_eq!(
                RData::read(
                    &mut decoder,
                    record_type_from_rdata(&expect),
                    Restrict::new(length)
                )
                .unwrap(),
                expect
            );
        }
    }

    fn record_type_from_rdata(rdata: &RData) -> crate::rr::record_type::RecordType {
        match *rdata {
            RData::A(..) => RecordType::A,
            RData::AAAA(..) => RecordType::AAAA,
            RData::ANAME(..) => RecordType::ANAME,
            RData::CAA(..) => RecordType::CAA,
            RData::CNAME(..) => RecordType::CNAME,
            RData::CSYNC(..) => RecordType::CSYNC,
            RData::HINFO(..) => RecordType::HINFO,
            RData::HTTPS(..) => RecordType::HTTPS,
            RData::MX(..) => RecordType::MX,
            RData::NAPTR(..) => RecordType::NAPTR,
            RData::NS(..) => RecordType::NS,
            RData::NULL(..) => RecordType::NULL,
            RData::OPENPGPKEY(..) => RecordType::OPENPGPKEY,
            RData::OPT(..) => RecordType::OPT,
            RData::PTR(..) => RecordType::PTR,
            RData::SOA(..) => RecordType::SOA,
            RData::SRV(..) => RecordType::SRV,
            RData::SSHFP(..) => RecordType::SSHFP,
            RData::SVCB(..) => RecordType::SVCB,
            RData::TLSA(..) => RecordType::TLSA,
            RData::TXT(..) => RecordType::TXT,
            #[cfg(feature = "dnssec")]
            RData::DNSSEC(ref rdata) => rdata.to_record_type(),
            RData::Unknown { code, .. } => RecordType::Unknown(code),
            RData::ZERO => RecordType::ZERO,
        }
    }

    #[test]
    fn test_write_to() {
        test_emit_data_set(get_data(), |e, d| d.emit(e));
    }
}