/*
 * MinIO Cloud Storage, (C) 2020 MinIO, 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 openid

import (
	"crypto"

	"github.com/dgrijalva/jwt-go"

	// Needed for SHA3 to work - See: https://golang.org/src/crypto/crypto.go?s=1034:1288
	_ "golang.org/x/crypto/sha3"
)

// Specific instances for EC256 and company
var (
	SigningMethodES3256 *jwt.SigningMethodECDSA
	SigningMethodES3384 *jwt.SigningMethodECDSA
	SigningMethodES3512 *jwt.SigningMethodECDSA
)

func init() {
	// ES256
	SigningMethodES3256 = &jwt.SigningMethodECDSA{Name: "ES3256", Hash: crypto.SHA3_256, KeySize: 32, CurveBits: 256}
	jwt.RegisterSigningMethod(SigningMethodES3256.Alg(), func() jwt.SigningMethod {
		return SigningMethodES3256
	})

	// ES384
	SigningMethodES3384 = &jwt.SigningMethodECDSA{Name: "ES3384", Hash: crypto.SHA3_384, KeySize: 48, CurveBits: 384}
	jwt.RegisterSigningMethod(SigningMethodES3384.Alg(), func() jwt.SigningMethod {
		return SigningMethodES3384
	})

	// ES512
	SigningMethodES3512 = &jwt.SigningMethodECDSA{Name: "ES3512", Hash: crypto.SHA3_512, KeySize: 66, CurveBits: 521}
	jwt.RegisterSigningMethod(SigningMethodES3512.Alg(), func() jwt.SigningMethod {
		return SigningMethodES3512
	})
}