opts_idemix.go

// Copyright © 2018 The IPFN Developers. All Rights Reserved.
// Copyright © 2016-2018 IBM Corp. All Rights Reserved.
//
// 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 bccsp

import "crypto"

const (
	// IDEMIX constant to identify Idemix related algorithms
	IDEMIX = "IDEMIX"
)

// IdemixIssuerKeyGenOpts contains the options for the Idemix Issuer key-generation.
// A list of attribytes may be optionally passed
type IdemixIssuerKeyGenOpts struct {
	// Temporary tells if the key is ephemeral
	Temporary bool
	// AttributeNames is a list of attributes
	AttributeNames []string
}

// Algorithm returns the key generation algorithm identifier (to be used).
func (*IdemixIssuerKeyGenOpts) Algorithm() string {
	return IDEMIX
}

// Ephemeral returns true if the key to generate has to be ephemeral,
// false otherwise.
func (o *IdemixIssuerKeyGenOpts) Ephemeral() bool {
	return o.Temporary
}

// IdemixUserSecretKeyGenOpts contains the options for the generation of an Idemix credential secret key.
type IdemixUserSecretKeyGenOpts struct {
	Temporary bool
}

// Algorithm returns the key generation algorithm identifier (to be used).
func (*IdemixUserSecretKeyGenOpts) Algorithm() string {
	return IDEMIX
}

// Ephemeral returns true if the key to generate has to be ephemeral,
// false otherwise.
func (o *IdemixUserSecretKeyGenOpts) Ephemeral() bool {
	return o.Temporary
}

// IdemixNymKeyDerivationOpts contains the options to create a new unlinkable pseudonym from a
// credential secret key with the respect to the specified issuer public key
type IdemixNymKeyDerivationOpts struct {
	// Temporary tells if the key is ephemeral
	Temporary bool
	// IssuerPK is the public-key of the issuer
	IssuerPK Key
}

// Algorithm returns the key derivation algorithm identifier (to be used).
func (*IdemixNymKeyDerivationOpts) Algorithm() string {
	return IDEMIX
}

// Ephemeral returns true if the key to derive has to be ephemeral,
// false otherwise.
func (o *IdemixNymKeyDerivationOpts) Ephemeral() bool {
	return o.Temporary
}

// IssuerPublicKey returns the issuer public key used to derive
// a new unlinkable pseudonym from a credential secret key
func (o *IdemixNymKeyDerivationOpts) IssuerPublicKey() Key {
	return o.IssuerPK
}

// IdemixCredentialRequestSignerOpts contains the option to create a Idemix credential request.
type IdemixCredentialRequestSignerOpts struct {
	// Attributes contains a list of indices of the attributes to be included in the
	// credential. The indices are with the respect to IdemixIssuerKeyGenOpts#AttributeNames.
	Attributes []int
	// HashFun is the hash function to be used
	H crypto.Hash
}

func (o *IdemixCredentialRequestSignerOpts) HashFunc() crypto.Hash {
	return o.H
}

// IdemixCredentialSignerOpts contains the options to produce a credential starting from a credential request
type IdemixCredentialSignerOpts struct {
	Attributes []int
	// HashFun is the hash function to be used
	H crypto.Hash
}

// HashFunc returns an identifier for the hash function used to produce
// the message passed to Signer.Sign, or else zero to indicate that no
// hashing was done.
func (o *IdemixCredentialSignerOpts) HashFunc() crypto.Hash {
	return o.H
}

// IdemixSignerOpts contains the options to generate an Idemix signature
type IdemixSignerOpts struct {
	// Nym is the pseudonym to be used
	Nym Key
	// IssuerPK is the public-key of the issuer
	IssuerPK Key
	// Credential is the byte representation of the credential signed by the issuer
	Credential []byte
	// Disclosure specifies which attribute should be disclosed. If Disclosure[i] = 0
	// then the i-th credential attribute should not be disclosed, otherwise the i-th
	// credential attribute will be disclosed.
	Disclosure []byte
	// H is the hash function to be used
	H crypto.Hash
}

func (o *IdemixSignerOpts) HashFunc() crypto.Hash {
	return o.H
}

// IdemixNymSignerOpts contains the options to generate an idemix pseudonym signature.
type IdemixNymSignerOpts struct {
	// Nym is the pseudonym to be used
	Nym Key
	// IssuerPK is the public-key of the issuer
	IssuerPK Key
	// H is the hash function to be used
	H crypto.Hash
}

// HashFunc returns an identifier for the hash function used to produce
// the message passed to Signer.Sign, or else zero to indicate that no
// hashing was done.
func (o *IdemixNymSignerOpts) HashFunc() crypto.Hash {
	return o.H
}