consul/vendor/github.com/SermoDigital/jose/crypto/rsa_pss.go

97 lines
2.3 KiB
Go

// +build go1.4
package crypto
import (
"crypto"
"crypto/rand"
"crypto/rsa"
"encoding/json"
)
// SigningMethodRSAPSS implements the RSAPSS family of SigningMethods.
type SigningMethodRSAPSS struct {
*SigningMethodRSA
Options *rsa.PSSOptions
}
// Specific instances for RS/PS SigningMethods.
var (
// SigningMethodPS256 implements PS256.
SigningMethodPS256 = &SigningMethodRSAPSS{
&SigningMethodRSA{
Name: "PS256",
Hash: crypto.SHA256,
},
&rsa.PSSOptions{
SaltLength: rsa.PSSSaltLengthAuto,
Hash: crypto.SHA256,
},
}
// SigningMethodPS384 implements PS384.
SigningMethodPS384 = &SigningMethodRSAPSS{
&SigningMethodRSA{
Name: "PS384",
Hash: crypto.SHA384,
},
&rsa.PSSOptions{
SaltLength: rsa.PSSSaltLengthAuto,
Hash: crypto.SHA384,
},
}
// SigningMethodPS512 implements PS512.
SigningMethodPS512 = &SigningMethodRSAPSS{
&SigningMethodRSA{
Name: "PS512",
Hash: crypto.SHA512,
},
&rsa.PSSOptions{
SaltLength: rsa.PSSSaltLengthAuto,
Hash: crypto.SHA512,
},
}
)
// Verify implements the Verify method from SigningMethod.
// For this verify method, key must be an *rsa.PublicKey.
func (m *SigningMethodRSAPSS) Verify(raw []byte, signature Signature, key interface{}) error {
rsaKey, ok := key.(*rsa.PublicKey)
if !ok {
return ErrInvalidKey
}
return rsa.VerifyPSS(rsaKey, m.Hash, m.sum(raw), signature, m.Options)
}
// Sign implements the Sign method from SigningMethod.
// For this signing method, key must be an *rsa.PrivateKey.
func (m *SigningMethodRSAPSS) Sign(raw []byte, key interface{}) (Signature, error) {
rsaKey, ok := key.(*rsa.PrivateKey)
if !ok {
return nil, ErrInvalidKey
}
sigBytes, err := rsa.SignPSS(rand.Reader, rsaKey, m.Hash, m.sum(raw), m.Options)
if err != nil {
return nil, err
}
return Signature(sigBytes), nil
}
func (m *SigningMethodRSAPSS) sum(b []byte) []byte {
h := m.Hash.New()
h.Write(b)
return h.Sum(nil)
}
// Hasher implements the Hasher method from SigningMethod.
func (m *SigningMethodRSAPSS) Hasher() crypto.Hash { return m.Hash }
// MarshalJSON implements json.Marshaler.
// See SigningMethodECDSA.MarshalJSON() for information.
func (m *SigningMethodRSAPSS) MarshalJSON() ([]byte, error) {
return []byte(`"` + m.Alg() + `"`), nil
}
var _ json.Marshaler = (*SigningMethodRSAPSS)(nil)