dex/vendor/gopkg.in/square/go-jose.v2/opaque.go
2020-01-31 10:32:00 +01:00

144 lines
4.1 KiB
Go

/*-
* Copyright 2018 Square Inc.
*
* 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 jose
// OpaqueSigner is an interface that supports signing payloads with opaque
// private key(s). Private key operations preformed by implementors may, for
// example, occur in a hardware module. An OpaqueSigner may rotate signing keys
// transparently to the user of this interface.
type OpaqueSigner interface {
// Public returns the public key of the current signing key.
Public() *JSONWebKey
// Algs returns a list of supported signing algorithms.
Algs() []SignatureAlgorithm
// SignPayload signs a payload with the current signing key using the given
// algorithm.
SignPayload(payload []byte, alg SignatureAlgorithm) ([]byte, error)
}
type opaqueSigner struct {
signer OpaqueSigner
}
func newOpaqueSigner(alg SignatureAlgorithm, signer OpaqueSigner) (recipientSigInfo, error) {
var algSupported bool
for _, salg := range signer.Algs() {
if alg == salg {
algSupported = true
break
}
}
if !algSupported {
return recipientSigInfo{}, ErrUnsupportedAlgorithm
}
return recipientSigInfo{
sigAlg: alg,
publicKey: signer.Public,
signer: &opaqueSigner{
signer: signer,
},
}, nil
}
func (o *opaqueSigner) signPayload(payload []byte, alg SignatureAlgorithm) (Signature, error) {
out, err := o.signer.SignPayload(payload, alg)
if err != nil {
return Signature{}, err
}
return Signature{
Signature: out,
protected: &rawHeader{},
}, nil
}
// OpaqueVerifier is an interface that supports verifying payloads with opaque
// public key(s). An OpaqueSigner may rotate signing keys transparently to the
// user of this interface.
type OpaqueVerifier interface {
VerifyPayload(payload []byte, signature []byte, alg SignatureAlgorithm) error
}
type opaqueVerifier struct {
verifier OpaqueVerifier
}
func (o *opaqueVerifier) verifyPayload(payload []byte, signature []byte, alg SignatureAlgorithm) error {
return o.verifier.VerifyPayload(payload, signature, alg)
}
// OpaqueKeyEncrypter is an interface that supports encrypting keys with an opaque key.
type OpaqueKeyEncrypter interface {
// KeyID returns the kid
KeyID() string
// Algs returns a list of supported key encryption algorithms.
Algs() []KeyAlgorithm
// encryptKey encrypts the CEK using the given algorithm.
encryptKey(cek []byte, alg KeyAlgorithm) (recipientInfo, error)
}
type opaqueKeyEncrypter struct {
encrypter OpaqueKeyEncrypter
}
func newOpaqueKeyEncrypter(alg KeyAlgorithm, encrypter OpaqueKeyEncrypter) (recipientKeyInfo, error) {
var algSupported bool
for _, salg := range encrypter.Algs() {
if alg == salg {
algSupported = true
break
}
}
if !algSupported {
return recipientKeyInfo{}, ErrUnsupportedAlgorithm
}
return recipientKeyInfo{
keyID: encrypter.KeyID(),
keyAlg: alg,
keyEncrypter: &opaqueKeyEncrypter{
encrypter: encrypter,
},
}, nil
}
func (oke *opaqueKeyEncrypter) encryptKey(cek []byte, alg KeyAlgorithm) (recipientInfo, error) {
return oke.encrypter.encryptKey(cek, alg)
}
//OpaqueKeyDecrypter is an interface that supports decrypting keys with an opaque key.
type OpaqueKeyDecrypter interface {
DecryptKey(encryptedKey []byte, header Header) ([]byte, error)
}
type opaqueKeyDecrypter struct {
decrypter OpaqueKeyDecrypter
}
func (okd *opaqueKeyDecrypter) decryptKey(headers rawHeader, recipient *recipientInfo, generator keyGenerator) ([]byte, error) {
mergedHeaders := rawHeader{}
mergedHeaders.merge(&headers)
mergedHeaders.merge(recipient.header)
header, err := mergedHeaders.sanitized()
if err != nil {
return nil, err
}
return okd.decrypter.DecryptKey(recipient.encryptedKey, header)
}