forked from zmap/zgrab
-
Notifications
You must be signed in to change notification settings - Fork 1
/
x509.go
2392 lines (2108 loc) · 73.6 KB
/
x509.go
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
// Copyright 2009 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// Package x509 parses X.509-encoded keys and certificates.
package x509
import (
// all of the hash libraries need to be imported for side-effects,
// so that crypto.RegisterHash is called
_ "crypto/md5"
"crypto/sha1"
"crypto/sha256"
_ "crypto/sha512"
"bytes"
"crypto"
"crypto/dsa"
"crypto/ecdsa"
"crypto/elliptic"
"crypto/rsa"
"encoding/asn1"
"encoding/pem"
"errors"
"fmt"
"io"
"math/big"
"net"
"strconv"
"time"
"github.com/zmap/zgrab/ztools/x509/pkix"
"github.com/zmap/zgrab/ztools/zct"
// "github.com/google/certificate-transparency/go"
)
// pkixPublicKey reflects a PKIX public key structure. See SubjectPublicKeyInfo
// in RFC 3280.
type pkixPublicKey struct {
Algo pkix.AlgorithmIdentifier
BitString asn1.BitString
}
// ParsePKIXPublicKey parses a DER encoded public key. These values are
// typically found in PEM blocks with "BEGIN PUBLIC KEY".
func ParsePKIXPublicKey(derBytes []byte) (pub interface{}, err error) {
var pki publicKeyInfo
if _, err = asn1.Unmarshal(derBytes, &pki); err != nil {
return
}
algo := getPublicKeyAlgorithmFromOID(pki.Algorithm.Algorithm)
if algo == UnknownPublicKeyAlgorithm {
return nil, errors.New("x509: unknown public key algorithm")
}
return parsePublicKey(algo, &pki)
}
func marshalPublicKey(pub interface{}) (publicKeyBytes []byte, publicKeyAlgorithm pkix.AlgorithmIdentifier, err error) {
switch pub := pub.(type) {
case *rsa.PublicKey:
publicKeyBytes, err = asn1.Marshal(rsaPublicKey{
N: pub.N,
E: pub.E,
})
publicKeyAlgorithm.Algorithm = oidPublicKeyRSA
// This is a NULL parameters value which is technically
// superfluous, but most other code includes it and, by
// doing this, we match their public key hashes.
publicKeyAlgorithm.Parameters = asn1.RawValue{
Tag: 5,
}
case *ecdsa.PublicKey:
publicKeyBytes = elliptic.Marshal(pub.Curve, pub.X, pub.Y)
oid, ok := oidFromNamedCurve(pub.Curve)
if !ok {
return nil, pkix.AlgorithmIdentifier{}, errors.New("x509: unsupported elliptic curve")
}
publicKeyAlgorithm.Algorithm = oidPublicKeyECDSA
var paramBytes []byte
paramBytes, err = asn1.Marshal(oid)
if err != nil {
return
}
publicKeyAlgorithm.Parameters.FullBytes = paramBytes
case *AugmentedECDSA:
return marshalPublicKey(pub.Pub)
default:
return nil, pkix.AlgorithmIdentifier{}, errors.New("x509: only RSA and ECDSA public keys supported")
}
return publicKeyBytes, publicKeyAlgorithm, nil
}
// MarshalPKIXPublicKey serialises a public key to DER-encoded PKIX format.
func MarshalPKIXPublicKey(pub interface{}) ([]byte, error) {
var publicKeyBytes []byte
var publicKeyAlgorithm pkix.AlgorithmIdentifier
var err error
if publicKeyBytes, publicKeyAlgorithm, err = marshalPublicKey(pub); err != nil {
return nil, err
}
pkix := pkixPublicKey{
Algo: publicKeyAlgorithm,
BitString: asn1.BitString{
Bytes: publicKeyBytes,
BitLength: 8 * len(publicKeyBytes),
},
}
ret, _ := asn1.Marshal(pkix)
return ret, nil
}
// These structures reflect the ASN.1 structure of X.509 certificates.:
type certificate struct {
Raw asn1.RawContent
TBSCertificate tbsCertificate
SignatureAlgorithm pkix.AlgorithmIdentifier
SignatureValue asn1.BitString
}
type tbsCertificate struct {
Raw asn1.RawContent
Version int `asn1:"optional,explicit,default:1,tag:0"`
SerialNumber *big.Int
SignatureAlgorithm pkix.AlgorithmIdentifier
Issuer asn1.RawValue
Validity validity
Subject asn1.RawValue
PublicKey publicKeyInfo
UniqueId asn1.BitString `asn1:"optional,tag:1"`
SubjectUniqueId asn1.BitString `asn1:"optional,tag:2"`
Extensions []pkix.Extension `asn1:"optional,explicit,tag:3"`
}
type dsaAlgorithmParameters struct {
P, Q, G *big.Int
}
type dsaSignature struct {
R, S *big.Int
}
type ecdsaSignature dsaSignature
type validity struct {
NotBefore, NotAfter time.Time
}
type publicKeyInfo struct {
Raw asn1.RawContent
Algorithm pkix.AlgorithmIdentifier
PublicKey asn1.BitString
}
type AugmentedECDSA struct {
Pub *ecdsa.PublicKey
Raw asn1.BitString
}
// RFC 5280, 4.2.1.1
type authKeyId struct {
Id []byte `asn1:"optional,tag:0"`
}
type SignatureAlgorithm int
type SignatureAlgorithmOID asn1.ObjectIdentifier
const (
UnknownSignatureAlgorithm SignatureAlgorithm = iota
MD2WithRSA
MD5WithRSA
SHA1WithRSA
SHA256WithRSA
SHA384WithRSA
SHA512WithRSA
DSAWithSHA1
DSAWithSHA256
ECDSAWithSHA1
ECDSAWithSHA256
ECDSAWithSHA384
ECDSAWithSHA512
total_signature_algorithms
)
var signatureAlgorithmNames = []string{
"unknown_algorithm",
"MD2WithRSA",
"MD5WithRSA",
"SHA1WithRSA",
"SHA256WithRSA",
"SHA384WithRSA",
"SHA512WithRSA",
"DSAWithSHA1",
"DSAWithSHA256",
"ECDSAWithSHA1",
"ECDSAWithSHA256",
"ECDSAWitHSHA384",
"ECDSAWithSHA512",
}
type PublicKeyAlgorithm int
const (
UnknownPublicKeyAlgorithm PublicKeyAlgorithm = iota
RSA
DSA
ECDSA
total_key_algorithms
)
var keyAlgorithmNames = []string{
"unknown_algorithm",
"RSA",
"DSA",
"ECDSA",
}
// OIDs for signature algorithms
//
// pkcs-1 OBJECT IDENTIFIER ::= {
// iso(1) member-body(2) us(840) rsadsi(113549) pkcs(1) 1 }
//
//
// RFC 3279 2.2.1 RSA Signature Algorithms
//
// md2WithRSAEncryption OBJECT IDENTIFIER ::= { pkcs-1 2 }
//
// md5WithRSAEncryption OBJECT IDENTIFIER ::= { pkcs-1 4 }
//
// sha-1WithRSAEncryption OBJECT IDENTIFIER ::= { pkcs-1 5 }
//
// dsaWithSha1 OBJECT IDENTIFIER ::= {
// iso(1) member-body(2) us(840) x9-57(10040) x9cm(4) 3 }
//
// RFC 3279 2.2.3 ECDSA Signature Algorithm
//
// ecdsa-with-SHA1 OBJECT IDENTIFIER ::= {
// iso(1) member-body(2) us(840) ansi-x962(10045)
// signatures(4) ecdsa-with-SHA1(1)}
//
//
// RFC 4055 5 PKCS #1 Version 1.5
//
// sha256WithRSAEncryption OBJECT IDENTIFIER ::= { pkcs-1 11 }
//
// sha384WithRSAEncryption OBJECT IDENTIFIER ::= { pkcs-1 12 }
//
// sha512WithRSAEncryption OBJECT IDENTIFIER ::= { pkcs-1 13 }
//
//
// RFC 5758 3.1 DSA Signature Algorithms
//
// dsaWithSha256 OBJECT IDENTIFIER ::= {
// joint-iso-ccitt(2) country(16) us(840) organization(1) gov(101)
// csor(3) algorithms(4) id-dsa-with-sha2(3) 2}
//
// RFC 5758 3.2 ECDSA Signature Algorithm
//
// ecdsa-with-SHA256 OBJECT IDENTIFIER ::= { iso(1) member-body(2)
// us(840) ansi-X9-62(10045) signatures(4) ecdsa-with-SHA2(3) 2 }
//
// ecdsa-with-SHA384 OBJECT IDENTIFIER ::= { iso(1) member-body(2)
// us(840) ansi-X9-62(10045) signatures(4) ecdsa-with-SHA2(3) 3 }
//
// ecdsa-with-SHA512 OBJECT IDENTIFIER ::= { iso(1) member-body(2)
// us(840) ansi-X9-62(10045) signatures(4) ecdsa-with-SHA2(3) 4 }
var (
oidSignatureMD2WithRSA = asn1.ObjectIdentifier{1, 2, 840, 113549, 1, 1, 2}
oidSignatureMD5WithRSA = asn1.ObjectIdentifier{1, 2, 840, 113549, 1, 1, 4}
oidSignatureSHA1WithRSA = asn1.ObjectIdentifier{1, 2, 840, 113549, 1, 1, 5}
oidSignatureSHA256WithRSA = asn1.ObjectIdentifier{1, 2, 840, 113549, 1, 1, 11}
oidSignatureSHA384WithRSA = asn1.ObjectIdentifier{1, 2, 840, 113549, 1, 1, 12}
oidSignatureSHA512WithRSA = asn1.ObjectIdentifier{1, 2, 840, 113549, 1, 1, 13}
oidSignatureDSAWithSHA1 = asn1.ObjectIdentifier{1, 2, 840, 10040, 4, 3}
oidSignatureDSAWithSHA256 = asn1.ObjectIdentifier{2, 16, 840, 1, 101, 4, 3, 2}
oidSignatureECDSAWithSHA1 = asn1.ObjectIdentifier{1, 2, 840, 10045, 4, 1}
oidSignatureECDSAWithSHA256 = asn1.ObjectIdentifier{1, 2, 840, 10045, 4, 3, 2}
oidSignatureECDSAWithSHA384 = asn1.ObjectIdentifier{1, 2, 840, 10045, 4, 3, 3}
oidSignatureECDSAWithSHA512 = asn1.ObjectIdentifier{1, 2, 840, 10045, 4, 3, 4}
)
var signatureAlgorithmDetails = []struct {
algo SignatureAlgorithm
oid asn1.ObjectIdentifier
pubKeyAlgo PublicKeyAlgorithm
hash crypto.Hash
}{
{MD2WithRSA, oidSignatureMD2WithRSA, RSA, crypto.Hash(0) /* no value for MD2 */},
{MD5WithRSA, oidSignatureMD5WithRSA, RSA, crypto.MD5},
{SHA1WithRSA, oidSignatureSHA1WithRSA, RSA, crypto.SHA1},
{SHA256WithRSA, oidSignatureSHA256WithRSA, RSA, crypto.SHA256},
{SHA384WithRSA, oidSignatureSHA384WithRSA, RSA, crypto.SHA384},
{SHA512WithRSA, oidSignatureSHA512WithRSA, RSA, crypto.SHA512},
{DSAWithSHA1, oidSignatureDSAWithSHA1, DSA, crypto.SHA1},
{DSAWithSHA256, oidSignatureDSAWithSHA256, DSA, crypto.SHA256},
{ECDSAWithSHA1, oidSignatureECDSAWithSHA1, ECDSA, crypto.SHA1},
{ECDSAWithSHA256, oidSignatureECDSAWithSHA256, ECDSA, crypto.SHA256},
{ECDSAWithSHA384, oidSignatureECDSAWithSHA384, ECDSA, crypto.SHA384},
{ECDSAWithSHA512, oidSignatureECDSAWithSHA512, ECDSA, crypto.SHA512},
}
func getSignatureAlgorithmFromOID(oid asn1.ObjectIdentifier) SignatureAlgorithm {
for _, details := range signatureAlgorithmDetails {
if oid.Equal(details.oid) {
return details.algo
}
}
return UnknownSignatureAlgorithm
}
// RFC 3279, 2.3 Public Key Algorithms
//
// pkcs-1 OBJECT IDENTIFIER ::== { iso(1) member-body(2) us(840)
// rsadsi(113549) pkcs(1) 1 }
//
// rsaEncryption OBJECT IDENTIFIER ::== { pkcs1-1 1 }
//
// id-dsa OBJECT IDENTIFIER ::== { iso(1) member-body(2) us(840)
// x9-57(10040) x9cm(4) 1 }
//
// RFC 5480, 2.1.1 Unrestricted Algorithm Identifier and Parameters
//
// id-ecPublicKey OBJECT IDENTIFIER ::= {
// iso(1) member-body(2) us(840) ansi-X9-62(10045) keyType(2) 1 }
var (
oidPublicKeyRSA = asn1.ObjectIdentifier{1, 2, 840, 113549, 1, 1, 1}
oidPublicKeyDSA = asn1.ObjectIdentifier{1, 2, 840, 10040, 4, 1}
oidPublicKeyECDSA = asn1.ObjectIdentifier{1, 2, 840, 10045, 2, 1}
)
func getPublicKeyAlgorithmFromOID(oid asn1.ObjectIdentifier) PublicKeyAlgorithm {
switch {
case oid.Equal(oidPublicKeyRSA):
return RSA
case oid.Equal(oidPublicKeyDSA):
return DSA
case oid.Equal(oidPublicKeyECDSA):
return ECDSA
}
return UnknownPublicKeyAlgorithm
}
func getMaxCertValidationLevel(oids []asn1.ObjectIdentifier) CertValidationLevel {
maxOID := DV
for _, oid := range oids {
if _, ok := ExtendedValidationOIDs[oid.String()]; ok {
return EV
} else if _, ok := OrganizationValidationOIDs[oid.String()]; ok {
maxOID = OV
}
}
return maxOID
}
// RFC 5480, 2.1.1.1. Named Curve
//
// secp224r1 OBJECT IDENTIFIER ::= {
// iso(1) identified-organization(3) certicom(132) curve(0) 33 }
//
// secp256r1 OBJECT IDENTIFIER ::= {
// iso(1) member-body(2) us(840) ansi-X9-62(10045) curves(3)
// prime(1) 7 }
//
// secp384r1 OBJECT IDENTIFIER ::= {
// iso(1) identified-organization(3) certicom(132) curve(0) 34 }
//
// secp521r1 OBJECT IDENTIFIER ::= {
// iso(1) identified-organization(3) certicom(132) curve(0) 35 }
//
// NB: secp256r1 is equivalent to prime256v1
var (
oidNamedCurveP224 = asn1.ObjectIdentifier{1, 3, 132, 0, 33}
oidNamedCurveP256 = asn1.ObjectIdentifier{1, 2, 840, 10045, 3, 1, 7}
oidNamedCurveP384 = asn1.ObjectIdentifier{1, 3, 132, 0, 34}
oidNamedCurveP521 = asn1.ObjectIdentifier{1, 3, 132, 0, 35}
)
func namedCurveFromOID(oid asn1.ObjectIdentifier) elliptic.Curve {
switch {
case oid.Equal(oidNamedCurveP224):
return elliptic.P224()
case oid.Equal(oidNamedCurveP256):
return elliptic.P256()
case oid.Equal(oidNamedCurveP384):
return elliptic.P384()
case oid.Equal(oidNamedCurveP521):
return elliptic.P521()
}
return nil
}
func oidFromNamedCurve(curve elliptic.Curve) (asn1.ObjectIdentifier, bool) {
switch curve {
case elliptic.P224():
return oidNamedCurveP224, true
case elliptic.P256():
return oidNamedCurveP256, true
case elliptic.P384():
return oidNamedCurveP384, true
case elliptic.P521():
return oidNamedCurveP521, true
}
return nil, false
}
// KeyUsage represents the set of actions that are valid for a given key. It's
// a bitmap of the KeyUsage* constants.
type KeyUsage int
const (
KeyUsageDigitalSignature KeyUsage = 1 << iota
KeyUsageContentCommitment
KeyUsageKeyEncipherment
KeyUsageDataEncipherment
KeyUsageKeyAgreement
KeyUsageCertSign
KeyUsageCRLSign
KeyUsageEncipherOnly
KeyUsageDecipherOnly
)
// RFC 5280, 4.2.1.12 Extended Key Usage
//
// anyExtendedKeyUsage OBJECT IDENTIFIER ::= { id-ce-extKeyUsage 0 }
//
// id-kp OBJECT IDENTIFIER ::= { id-pkix 3 }
//
// id-kp-serverAuth OBJECT IDENTIFIER ::= { id-kp 1 }
// id-kp-clientAuth OBJECT IDENTIFIER ::= { id-kp 2 }
// id-kp-codeSigning OBJECT IDENTIFIER ::= { id-kp 3 }
// id-kp-emailProtection OBJECT IDENTIFIER ::= { id-kp 4 }
// id-kp-timeStamping OBJECT IDENTIFIER ::= { id-kp 8 }
// id-kp-OCSPSigning OBJECT IDENTIFIER ::= { id-kp 9 }
var (
oidExtKeyUsageAny = asn1.ObjectIdentifier{2, 5, 29, 37, 0}
oidExtKeyUsageServerAuth = asn1.ObjectIdentifier{1, 3, 6, 1, 5, 5, 7, 3, 1}
oidExtKeyUsageClientAuth = asn1.ObjectIdentifier{1, 3, 6, 1, 5, 5, 7, 3, 2}
oidExtKeyUsageCodeSigning = asn1.ObjectIdentifier{1, 3, 6, 1, 5, 5, 7, 3, 3}
oidExtKeyUsageEmailProtection = asn1.ObjectIdentifier{1, 3, 6, 1, 5, 5, 7, 3, 4}
oidExtKeyUsageIPSECEndSystem = asn1.ObjectIdentifier{1, 3, 6, 1, 5, 5, 7, 3, 5}
oidExtKeyUsageIPSECTunnel = asn1.ObjectIdentifier{1, 3, 6, 1, 5, 5, 7, 3, 6}
oidExtKeyUsageIPSECUser = asn1.ObjectIdentifier{1, 3, 6, 1, 5, 5, 7, 3, 7}
oidExtKeyUsageTimeStamping = asn1.ObjectIdentifier{1, 3, 6, 1, 5, 5, 7, 3, 8}
oidExtKeyUsageOCSPSigning = asn1.ObjectIdentifier{1, 3, 6, 1, 5, 5, 7, 3, 9}
oidExtKeyUsageMicrosoftServerGatedCrypto = asn1.ObjectIdentifier{1, 3, 6, 1, 4, 1, 311, 10, 3, 3}
oidExtKeyUsageNetscapeServerGatedCrypto = asn1.ObjectIdentifier{2, 16, 840, 1, 113730, 4, 1}
)
// ExtKeyUsage represents an extended set of actions that are valid for a given key.
// Each of the ExtKeyUsage* constants define a unique action.
type ExtKeyUsage int
const (
ExtKeyUsageAny ExtKeyUsage = iota
ExtKeyUsageServerAuth
ExtKeyUsageClientAuth
ExtKeyUsageCodeSigning
ExtKeyUsageEmailProtection
ExtKeyUsageIPSECEndSystem
ExtKeyUsageIPSECTunnel
ExtKeyUsageIPSECUser
ExtKeyUsageTimeStamping
ExtKeyUsageOCSPSigning
ExtKeyUsageMicrosoftServerGatedCrypto
ExtKeyUsageNetscapeServerGatedCrypto
)
// extKeyUsageOIDs contains the mapping between an ExtKeyUsage and its OID.
var extKeyUsageOIDs = []struct {
extKeyUsage ExtKeyUsage
oid asn1.ObjectIdentifier
}{
{ExtKeyUsageAny, oidExtKeyUsageAny},
{ExtKeyUsageServerAuth, oidExtKeyUsageServerAuth},
{ExtKeyUsageClientAuth, oidExtKeyUsageClientAuth},
{ExtKeyUsageCodeSigning, oidExtKeyUsageCodeSigning},
{ExtKeyUsageEmailProtection, oidExtKeyUsageEmailProtection},
{ExtKeyUsageIPSECEndSystem, oidExtKeyUsageIPSECEndSystem},
{ExtKeyUsageIPSECTunnel, oidExtKeyUsageIPSECTunnel},
{ExtKeyUsageIPSECUser, oidExtKeyUsageIPSECUser},
{ExtKeyUsageTimeStamping, oidExtKeyUsageTimeStamping},
{ExtKeyUsageOCSPSigning, oidExtKeyUsageOCSPSigning},
{ExtKeyUsageMicrosoftServerGatedCrypto, oidExtKeyUsageMicrosoftServerGatedCrypto},
{ExtKeyUsageNetscapeServerGatedCrypto, oidExtKeyUsageNetscapeServerGatedCrypto},
}
func extKeyUsageFromOID(oid asn1.ObjectIdentifier) (eku ExtKeyUsage, ok bool) {
for _, pair := range extKeyUsageOIDs {
if oid.Equal(pair.oid) {
return pair.extKeyUsage, true
}
}
return
}
func oidFromExtKeyUsage(eku ExtKeyUsage) (oid asn1.ObjectIdentifier, ok bool) {
for _, pair := range extKeyUsageOIDs {
if eku == pair.extKeyUsage {
return pair.oid, true
}
}
return
}
// A Certificate represents an X.509 certificate.
type Certificate struct {
Raw []byte // Complete ASN.1 DER content (certificate, signature algorithm and signature).
RawTBSCertificate []byte // Certificate part of raw ASN.1 DER content.
RawSubjectPublicKeyInfo []byte // DER encoded SubjectPublicKeyInfo.
RawSubject []byte // DER encoded Subject
RawIssuer []byte // DER encoded Issuer
Signature []byte
SignatureAlgorithm SignatureAlgorithm
SignatureAlgorithmOID asn1.ObjectIdentifier
PublicKeyAlgorithm PublicKeyAlgorithm
PublicKey interface{}
PublicKeyAlgorithmOID asn1.ObjectIdentifier
Version int
SerialNumber *big.Int
Issuer pkix.Name
Subject pkix.Name
NotBefore, NotAfter time.Time // Validity bounds.
ValidityPeriod int
KeyUsage KeyUsage
IssuerUniqueId asn1.BitString
SubjectUniqueId asn1.BitString
// Extensions contains raw X.509 extensions. When parsing certificates,
// this can be used to extract non-critical extensions that are not
// parsed by this package. When marshaling certificates, the Extensions
// field is ignored, see ExtraExtensions.
Extensions []pkix.Extension
// ExtraExtensions contains extensions to be copied, raw, into any
// marshaled certificates. Values override any extensions that would
// otherwise be produced based on the other fields. The ExtraExtensions
// field is not populated when parsing certificates, see Extensions.
ExtraExtensions []pkix.Extension
// UnhandledCriticalExtensions contains a list of extension IDs that
// were not (fully) processed when parsing. Verify will fail if this
// slice is non-empty, unless verification is delegated to an OS
// library which understands all the critical extensions.
//
// Users can access these extensions using Extensions and can remove
// elements from this slice if they believe that they have been
// handled.
UnhandledCriticalExtensions []asn1.ObjectIdentifier
ExtKeyUsage []ExtKeyUsage // Sequence of extended key usages.
UnknownExtKeyUsage []asn1.ObjectIdentifier // Encountered extended key usages unknown to this package.
BasicConstraintsValid bool // if true then the next two fields are valid.
IsCA bool
MaxPathLen int
// MaxPathLenZero indicates that BasicConstraintsValid==true and
// MaxPathLen==0 should be interpreted as an actual Max path length
// of zero. Otherwise, that combination is interpreted as MaxPathLen
// not being set.
MaxPathLenZero bool
SubjectKeyId []byte
AuthorityKeyId []byte
// RFC 5280, 4.2.2.1 (Authority Information Access)
OCSPServer []string
IssuingCertificateURL []string
// Subject Alternate Name values
OtherNames []pkix.OtherName
DNSNames []string
EmailAddresses []string
DirectoryNames []pkix.Name
EDIPartyNames []pkix.EDIPartyName
URIs []string
IPAddresses []net.IP
RegisteredIDs []asn1.ObjectIdentifier
// Issuer Alternative Name values
IANOtherNames []pkix.OtherName
IANDNSNames []string
IANEmailAddresses []string
IANDirectoryNames []pkix.Name
IANEDIPartyNames []pkix.EDIPartyName
IANURIs []string
IANIPAddresses []net.IP
IANRegisteredIDs []asn1.ObjectIdentifier
// Certificate Policies values
QualifierId [][]asn1.ObjectIdentifier
ExplicitTexts [][]asn1.RawValue
NoticeRefOrgnization [][]asn1.RawValue
NoticeRefNumbers [][]NoticeNumber
// Name constraints
NameConstraintsCritical bool // if true then the name constraints are marked critical.
PermittedDNSDomainsCritical bool // deprecated, use NameConstraintsCritical
PermittedDNSDomains []GeneralSubtreeString
ExcludedDNSDomains []GeneralSubtreeString
PermittedEmailDomains []GeneralSubtreeString
ExcludedEmailDomains []GeneralSubtreeString
PermittedIPAddresses []GeneralSubtreeIP
ExcludedIPAddresses []GeneralSubtreeIP
PermittedDirectoryNames []GeneralSubtreeName
ExcludedDirectoryNames []GeneralSubtreeName
PermittedEdiPartyNames []GeneralSubtreeEdi
ExcludedEdiPartyNames []GeneralSubtreeEdi
PermittedRegisteredIDs []GeneralSubtreeOid
ExcludedRegisteredIDs []GeneralSubtreeOid
PermittedX400Addresses []GeneralSubtreeRaw
ExcludedX400Addresses []GeneralSubtreeRaw
// CRL Distribution Points
CRLDistributionPoints []string
PolicyIdentifiers []asn1.ObjectIdentifier
ValidationLevel CertValidationLevel
// Fingerprints
FingerprintMD5 CertificateFingerprint
FingerprintSHA1 CertificateFingerprint
FingerprintSHA256 CertificateFingerprint
FingerprintNoCT CertificateFingerprint
// SPKI
SPKIFingerprint CertificateFingerprint
SPKISubjectFingerprint CertificateFingerprint
TBSCertificateFingerprint CertificateFingerprint
IsPrecert bool
// Internal
validSignature bool
// CT
SignedCertificateTimestampList []*ct.SignedCertificateTimestamp
}
type NoticeNumber []int
type GeneralSubtreeString struct {
Data string
Max int
Min int
}
type GeneralSubtreeIP struct {
Data net.IPNet
Max int
Min int
}
type GeneralSubtreeName struct {
Data pkix.Name
Max int
Min int
}
type GeneralSubtreeEdi struct {
Data pkix.EDIPartyName
Max int
Min int
}
type GeneralSubtreeOid struct {
Data asn1.ObjectIdentifier
Max int
Min int
}
type GeneralSubtreeRaw struct {
Data asn1.RawValue
Max int
Min int
}
// ErrUnsupportedAlgorithm results from attempting to perform an operation that
// involves algorithms that are not currently implemented.
var ErrUnsupportedAlgorithm = errors.New("x509: cannot verify signature: algorithm unimplemented")
// ConstraintViolationError results when a requested usage is not permitted by
// a certificate. For example: checking a signature when the public key isn't a
// certificate signing key.
type ConstraintViolationError struct{}
func (ConstraintViolationError) Error() string {
return "x509: invalid signature: parent certificate cannot sign this kind of certificate"
}
func (c *Certificate) Equal(other *Certificate) bool {
return bytes.Equal(c.Raw, other.Raw)
}
// Entrust have a broken root certificate (CN=Entrust.net Certification
// Authority (2048)) which isn't marked as a CA certificate and is thus invalid
// according to PKIX.
// We recognise this certificate by its SubjectPublicKeyInfo and exempt it
// from the Basic Constraints requirement.
// See http://www.entrust.net/knowledge-base/technote.cfm?tn=7869
//
// TODO(agl): remove this hack once their reissued root is sufficiently
// widespread.
var entrustBrokenSPKI = []byte{
0x30, 0x82, 0x01, 0x22, 0x30, 0x0d, 0x06, 0x09,
0x2a, 0x86, 0x48, 0x86, 0xf7, 0x0d, 0x01, 0x01,
0x01, 0x05, 0x00, 0x03, 0x82, 0x01, 0x0f, 0x00,
0x30, 0x82, 0x01, 0x0a, 0x02, 0x82, 0x01, 0x01,
0x00, 0x97, 0xa3, 0x2d, 0x3c, 0x9e, 0xde, 0x05,
0xda, 0x13, 0xc2, 0x11, 0x8d, 0x9d, 0x8e, 0xe3,
0x7f, 0xc7, 0x4b, 0x7e, 0x5a, 0x9f, 0xb3, 0xff,
0x62, 0xab, 0x73, 0xc8, 0x28, 0x6b, 0xba, 0x10,
0x64, 0x82, 0x87, 0x13, 0xcd, 0x57, 0x18, 0xff,
0x28, 0xce, 0xc0, 0xe6, 0x0e, 0x06, 0x91, 0x50,
0x29, 0x83, 0xd1, 0xf2, 0xc3, 0x2a, 0xdb, 0xd8,
0xdb, 0x4e, 0x04, 0xcc, 0x00, 0xeb, 0x8b, 0xb6,
0x96, 0xdc, 0xbc, 0xaa, 0xfa, 0x52, 0x77, 0x04,
0xc1, 0xdb, 0x19, 0xe4, 0xae, 0x9c, 0xfd, 0x3c,
0x8b, 0x03, 0xef, 0x4d, 0xbc, 0x1a, 0x03, 0x65,
0xf9, 0xc1, 0xb1, 0x3f, 0x72, 0x86, 0xf2, 0x38,
0xaa, 0x19, 0xae, 0x10, 0x88, 0x78, 0x28, 0xda,
0x75, 0xc3, 0x3d, 0x02, 0x82, 0x02, 0x9c, 0xb9,
0xc1, 0x65, 0x77, 0x76, 0x24, 0x4c, 0x98, 0xf7,
0x6d, 0x31, 0x38, 0xfb, 0xdb, 0xfe, 0xdb, 0x37,
0x02, 0x76, 0xa1, 0x18, 0x97, 0xa6, 0xcc, 0xde,
0x20, 0x09, 0x49, 0x36, 0x24, 0x69, 0x42, 0xf6,
0xe4, 0x37, 0x62, 0xf1, 0x59, 0x6d, 0xa9, 0x3c,
0xed, 0x34, 0x9c, 0xa3, 0x8e, 0xdb, 0xdc, 0x3a,
0xd7, 0xf7, 0x0a, 0x6f, 0xef, 0x2e, 0xd8, 0xd5,
0x93, 0x5a, 0x7a, 0xed, 0x08, 0x49, 0x68, 0xe2,
0x41, 0xe3, 0x5a, 0x90, 0xc1, 0x86, 0x55, 0xfc,
0x51, 0x43, 0x9d, 0xe0, 0xb2, 0xc4, 0x67, 0xb4,
0xcb, 0x32, 0x31, 0x25, 0xf0, 0x54, 0x9f, 0x4b,
0xd1, 0x6f, 0xdb, 0xd4, 0xdd, 0xfc, 0xaf, 0x5e,
0x6c, 0x78, 0x90, 0x95, 0xde, 0xca, 0x3a, 0x48,
0xb9, 0x79, 0x3c, 0x9b, 0x19, 0xd6, 0x75, 0x05,
0xa0, 0xf9, 0x88, 0xd7, 0xc1, 0xe8, 0xa5, 0x09,
0xe4, 0x1a, 0x15, 0xdc, 0x87, 0x23, 0xaa, 0xb2,
0x75, 0x8c, 0x63, 0x25, 0x87, 0xd8, 0xf8, 0x3d,
0xa6, 0xc2, 0xcc, 0x66, 0xff, 0xa5, 0x66, 0x68,
0x55, 0x02, 0x03, 0x01, 0x00, 0x01,
}
// CheckSignatureFrom verifies that the signature on c is a valid signature
// from parent.
func (c *Certificate) CheckSignatureFrom(parent *Certificate) (err error) {
// RFC 5280, 4.2.1.9:
// "If the basic constraints extension is not present in a version 3
// certificate, or the extension is present but the cA boolean is not
// asserted, then the certified public key MUST NOT be used to verify
// certificate signatures."
// (except for Entrust, see comment above entrustBrokenSPKI)
if (parent.Version == 3 && !parent.BasicConstraintsValid ||
parent.BasicConstraintsValid && !parent.IsCA) &&
!bytes.Equal(c.RawSubjectPublicKeyInfo, entrustBrokenSPKI) {
return ConstraintViolationError{}
}
if parent.KeyUsage != 0 && parent.KeyUsage&KeyUsageCertSign == 0 {
return ConstraintViolationError{}
}
if parent.PublicKeyAlgorithm == UnknownPublicKeyAlgorithm {
return ErrUnsupportedAlgorithm
}
// TODO(agl): don't ignore the path length constraint.
if parent.Subject.String() != c.Issuer.String() {
return errors.New("Mis-match issuer/subject")
}
return parent.CheckSignature(c.SignatureAlgorithm, c.RawTBSCertificate, c.Signature)
}
// CheckSignature verifies that signature is a valid signature over signed from
// c's public key.
func (c *Certificate) CheckSignature(algo SignatureAlgorithm, signed, signature []byte) (err error) {
var hashType crypto.Hash
switch algo {
case SHA1WithRSA, DSAWithSHA1, ECDSAWithSHA1:
hashType = crypto.SHA1
case SHA256WithRSA, DSAWithSHA256, ECDSAWithSHA256:
hashType = crypto.SHA256
case SHA384WithRSA, ECDSAWithSHA384:
hashType = crypto.SHA384
case SHA512WithRSA, ECDSAWithSHA512:
hashType = crypto.SHA512
default:
return ErrUnsupportedAlgorithm
}
if !hashType.Available() {
return ErrUnsupportedAlgorithm
}
h := hashType.New()
h.Write(signed)
digest := h.Sum(nil)
switch pub := c.PublicKey.(type) {
case *rsa.PublicKey:
return rsa.VerifyPKCS1v15(pub, hashType, digest, signature)
case *dsa.PublicKey:
dsaSig := new(dsaSignature)
if _, err := asn1.Unmarshal(signature, dsaSig); err != nil {
return err
}
if dsaSig.R.Sign() <= 0 || dsaSig.S.Sign() <= 0 {
return errors.New("x509: DSA signature contained zero or negative values")
}
if !dsa.Verify(pub, digest, dsaSig.R, dsaSig.S) {
return errors.New("x509: DSA verification failure")
}
return
case *ecdsa.PublicKey:
ecdsaSig := new(ecdsaSignature)
if _, err := asn1.Unmarshal(signature, ecdsaSig); err != nil {
return err
}
if ecdsaSig.R.Sign() <= 0 || ecdsaSig.S.Sign() <= 0 {
return errors.New("x509: ECDSA signature contained zero or negative values")
}
if !ecdsa.Verify(pub, digest, ecdsaSig.R, ecdsaSig.S) {
return errors.New("x509: ECDSA verification failure")
}
return
case *AugmentedECDSA:
ecdsaSig := new(ecdsaSignature)
if _, err := asn1.Unmarshal(signature, ecdsaSig); err != nil {
return err
}
if ecdsaSig.R.Sign() <= 0 || ecdsaSig.S.Sign() <= 0 {
return errors.New("x509: ECDSA signature contained zero or negative values")
}
if !ecdsa.Verify(pub.Pub, digest, ecdsaSig.R, ecdsaSig.S) {
return errors.New("x509: ECDSA verification failure")
}
return
}
return ErrUnsupportedAlgorithm
}
// CheckCRLSignature checks that the signature in crl is from c.
func (c *Certificate) CheckCRLSignature(crl *pkix.CertificateList) (err error) {
algo := getSignatureAlgorithmFromOID(crl.SignatureAlgorithm.Algorithm)
return c.CheckSignature(algo, crl.TBSCertList.Raw, crl.SignatureValue.RightAlign())
}
type UnhandledCriticalExtension struct {
oid asn1.ObjectIdentifier
message string
}
func (h UnhandledCriticalExtension) Error() string {
return fmt.Sprintf("x509: unhandled critical extension: %s | %s", h.oid, h.message)
}
type basicConstraints struct {
IsCA bool `asn1:"optional"`
MaxPathLen int `asn1:"optional,default:-1"`
}
// RFC 5280 4.2.1.4
type policyInformation struct {
Policy asn1.ObjectIdentifier
Qualifiers []policyQualifierInfo `asn1:"optional"`
}
type policyQualifierInfo struct {
PolicyQualifierId asn1.ObjectIdentifier
Qualifier asn1.RawValue
}
type userNotice struct {
NoticeRef noticeReference `asn1:"optional"`
ExplicitText asn1.RawValue `asn1:"optional"`
}
type noticeReference struct {
Organization asn1.RawValue
NoticeNumbers []int
}
// RFC 5280, 4.2.1.10
type nameConstraints struct {
Permitted []generalSubtree `asn1:"optional,tag:0"`
Excluded []generalSubtree `asn1:"optional,tag:1"`
}
type generalSubtree struct {
Value asn1.RawValue `asn1:"optional"`
Min int `asn1:"tag:0,default:0,optional"`
Max int `asn1:"tag:1,optional"`
}
// RFC 5280, 4.2.2.1
type authorityInfoAccess struct {
Method asn1.ObjectIdentifier
Location asn1.RawValue
}
// RFC 5280, 4.2.1.14
type distributionPoint struct {
DistributionPoint distributionPointName `asn1:"optional,tag:0"`
Reason asn1.BitString `asn1:"optional,tag:1"`
CRLIssuer asn1.RawValue `asn1:"optional,tag:2"`
}
type distributionPointName struct {
FullName asn1.RawValue `asn1:"optional,tag:0"`
RelativeName pkix.RDNSequence `asn1:"optional,tag:1"`
}
func parsePublicKey(algo PublicKeyAlgorithm, keyData *publicKeyInfo) (interface{}, error) {
asn1Data := keyData.PublicKey.RightAlign()
switch algo {
case RSA:
p := new(rsaPublicKey)
_, err := asn1.Unmarshal(asn1Data, p)
if err != nil {
return nil, err
}
if p.N.Sign() <= 0 {
return nil, errors.New("x509: RSA modulus is not a positive number")
}
if p.E <= 0 {
return nil, errors.New("x509: RSA public exponent is not a positive number")
}
pub := &rsa.PublicKey{
E: p.E,
N: p.N,
}
return pub, nil
case DSA:
var p *big.Int
_, err := asn1.Unmarshal(asn1Data, &p)
if err != nil {
return nil, err
}
paramsData := keyData.Algorithm.Parameters.FullBytes
params := new(dsaAlgorithmParameters)
_, err = asn1.Unmarshal(paramsData, params)
if err != nil {
return nil, err
}
if p.Sign() <= 0 || params.P.Sign() <= 0 || params.Q.Sign() <= 0 || params.G.Sign() <= 0 {
return nil, errors.New("x509: zero or negative DSA parameter")
}
pub := &dsa.PublicKey{
Parameters: dsa.Parameters{
P: params.P,
Q: params.Q,
G: params.G,
},
Y: p,
}
return pub, nil
case ECDSA:
paramsData := keyData.Algorithm.Parameters.FullBytes
namedCurveOID := new(asn1.ObjectIdentifier)
_, err := asn1.Unmarshal(paramsData, namedCurveOID)
if err != nil {
return nil, err
}
namedCurve := namedCurveFromOID(*namedCurveOID)
if namedCurve == nil {
return nil, errors.New("x509: unsupported elliptic curve")
}
x, y := elliptic.Unmarshal(namedCurve, asn1Data)
if x == nil {
return nil, errors.New("x509: failed to unmarshal elliptic curve point")
}
key := &ecdsa.PublicKey{
Curve: namedCurve,
X: x,
Y: y,
}
pub := &AugmentedECDSA{
Pub: key,
Raw: keyData.PublicKey,
}
return pub, nil
default: