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
|
// Copyright 2022 Google LLC
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package rsassapss
import (
"errors"
"fmt"
"math/big"
"google.golang.org/protobuf/proto"
"github.com/tink-crypto/tink-go/v2/core/registry"
"github.com/tink-crypto/tink-go/v2/internal/internalapi"
"github.com/tink-crypto/tink-go/v2/internal/protoserialization"
internal "github.com/tink-crypto/tink-go/v2/internal/signature"
"github.com/tink-crypto/tink-go/v2/keyset"
rsassapsspb "github.com/tink-crypto/tink-go/v2/proto/rsa_ssa_pss_go_proto"
tinkpb "github.com/tink-crypto/tink-go/v2/proto/tink_go_proto"
)
const (
verifierKeyVersion = 0
verifierTypeURL = "type.googleapis.com/google.crypto.tink.RsaSsaPssPublicKey"
)
var (
errInvalidVerifierKey = errors.New("rsassapss_verifier_key_manager: invalid key")
errUnimplemented = errors.New("rsassapss_verifier_key_manager: not implemented")
)
type verifierKeyManager struct{}
var _ (registry.KeyManager) = (*verifierKeyManager)(nil)
func (km *verifierKeyManager) Primitive(serializedKey []byte) (any, error) {
keySerialization, err := protoserialization.NewKeySerialization(&tinkpb.KeyData{
TypeUrl: verifierTypeURL,
Value: serializedKey,
KeyMaterialType: tinkpb.KeyData_ASYMMETRIC_PUBLIC,
}, tinkpb.OutputPrefixType_RAW, 0)
if err != nil {
return nil, err
}
key, err := protoserialization.ParseKey(keySerialization)
if err != nil {
return nil, err
}
verifierKey, ok := key.(*PublicKey)
if !ok {
return nil, fmt.Errorf("rsassapss_verifier_key_manager: invalid key type: got %T, want %T", key, (*PublicKey)(nil))
}
return NewVerifier(verifierKey, internalapi.Token{})
}
func validateRSAPSSPublicKey(pubKey *rsassapsspb.RsaSsaPssPublicKey) error {
if err := keyset.ValidateKeyVersion(pubKey.GetVersion(), verifierKeyVersion); err != nil {
return err
}
if pubKey.GetParams().GetSigHash() != pubKey.GetParams().GetMgf1Hash() {
return fmt.Errorf("signature hash and MGF1 hash function must match")
}
if pubKey.GetParams().GetSaltLength() < 0 {
return fmt.Errorf("salt length can't be negative")
}
return internal.ValidateRSAPublicKeyParams(pubKey.GetParams().GetSigHash(), new(big.Int).SetBytes(pubKey.GetN()).BitLen(), pubKey.GetE())
}
func (km *verifierKeyManager) NewKey(serializedKeyFormat []byte) (proto.Message, error) {
return nil, errUnimplemented
}
func (km *verifierKeyManager) NewKeyData(serializedKeyFormat []byte) (*tinkpb.KeyData, error) {
return nil, errUnimplemented
}
func (km *verifierKeyManager) DoesSupport(typeURL string) bool {
return typeURL == verifierTypeURL
}
func (km *verifierKeyManager) TypeURL() string {
return verifierTypeURL
}
|
