Class UniversalAccumulator

VB accumulator that supports both membership proofs and non-membership proofs. For guarding against forgery of non-membership proofs (details in the paper), during initialization, it should generate several accumulator members and never remove them from accumulator, nor it should allow duplicates of them to be added. Thus, several methods accept an optional persistent database IInitialElementsStore which stores those initial elements.

Hierarchy (view full)

Accumulator<Uint8Array>
- UniversalAccumulator

Index

Constructors

constructor

new UniversalAccumulator(__namedParameters): UniversalAccumulator
Construct an accumulator object.
Parameters
- __namedParameters: any
Returns UniversalAccumulator
Inherited from Accumulator.constructor
- Defined in accumulator/accumulator.ts:67

Properties

params

params: undefined | AccumulatorParams

secretKey

secretKey: undefined | AccumulatorSecretKey

value

value: {
    f_V: Uint8Array;
    maxSize: number;
    V: Uint8Array;
}

f_V is supposed to kept private by the accumulator manager. V is the accumulated value.

Accessors

accumulated

get accumulated(): Uint8Array
Get the accumulated value.

Returns Uint8Array
Overrides Accumulator.accumulated
- Defined in accumulator/accumulator.ts:661

Methods

add

add(element, secretKey?, state?, initialElementsStore?): Promise<void>
Add a single element to the accumulator
Parameters
- element: Uint8Array
  The element to add.
- OptionalsecretKey: AccumulatorSecretKey
  If secret key is not provided, its expected to find the secret key on the object.
- Optionalstate: IAccumulatorState
  If state is provided it is checked before computing the new accumulator and updated with new element after computing the new accumulator. Throws error if element present.
- OptionalinitialElementsStore: IInitialElementsStore
  if provided, check that the element is not part of the initial elements, throws error if it is.
Returns Promise<void>
Overrides Accumulator.add
- Defined in accumulator/accumulator.ts:677

addBatch

addBatch(elements, secretKey?, state?, initialElementsStore?): Promise<void>
Add a batch of elements to the accumulator.
Parameters
- elements: Uint8Array[]
- OptionalsecretKey: AccumulatorSecretKey
- Optionalstate: IAccumulatorState
  If state is provided it is checked before computing the new accumulator and updated with new elements after computing the new accumulator
- OptionalinitialElementsStore: IInitialElementsStore
Returns Promise<void>
Overrides Accumulator.addBatch
- Defined in accumulator/accumulator.ts:709

`Protected`addBatchToState

addBatchToState(elements, state?): Promise<void>
Protected
If state is provided, add the batch of elements to the state
Parameters
- elements: Uint8Array[]
- Optionalstate: IAccumulatorState
Returns Promise<void>
Inherited from Accumulator.addBatchToState
- Defined in accumulator/accumulator.ts:380

addRemoveBatches

addRemoveBatches(additions, removals, secretKey?, state?, initialElementsStore?): Promise<void>
Add and remove batches of elements.
Parameters
- additions: Uint8Array[]
  The batch to be added
- removals: Uint8Array[]
  The batch to be removed.
- OptionalsecretKey: AccumulatorSecretKey
- Optionalstate: IAccumulatorState
  If state is provided it is checked before computing the new accumulator and updated by adding and removing given elements after computing the new accumulator.
- OptionalinitialElementsStore: IInitialElementsStore
Returns Promise<void>
Overrides Accumulator.addRemoveBatches
- Defined in accumulator/accumulator.ts:733

`Protected`addToState

addToState(element, state?): Promise<void>
Protected
If state is provided, add the element to the state
Parameters
- element: Uint8Array
- Optionalstate: IAccumulatorState
Returns Promise<void>
Inherited from Accumulator.addToState
- Defined in accumulator/accumulator.ts:356

`Protected`checkBeforeAdd

checkBeforeAdd(element, state?, initialElementsStore?): Promise<void>
Protected
Checks to do before adding a new element
Parameters
- element: Uint8Array
- Optionalstate: IAccumulatorState
- OptionalinitialElementsStore: IInitialElementsStore
Returns Promise<void>
- Defined in accumulator/accumulator.ts:1011

`Protected`checkBeforeAddBatch

checkBeforeAddBatch(elements, state?, initialElementsStore?): Promise<void>
Protected
Checks to do before adding several elements as a batch
Parameters
- elements: Uint8Array[]
- Optionalstate: IAccumulatorState
- OptionalinitialElementsStore: IInitialElementsStore
Returns Promise<void>
- Defined in accumulator/accumulator.ts:1043

`Protected`checkBeforeRemove

checkBeforeRemove(element, state?, initialElementsStore?): Promise<void>
Protected
Checks to do before removing an existing element
Parameters
- element: Uint8Array
- Optionalstate: IAccumulatorState
- OptionalinitialElementsStore: IInitialElementsStore
Returns Promise<void>
- Defined in accumulator/accumulator.ts:1027

`Protected`checkBeforeRemoveBatch

checkBeforeRemoveBatch(elements, state?, initialElementsStore?): Promise<void>
Protected
Checks to do before removing several elements as a batch
Parameters
- elements: Uint8Array[]
- Optionalstate: IAccumulatorState
- OptionalinitialElementsStore: IInitialElementsStore
Returns Promise<void>
- Defined in accumulator/accumulator.ts:1063

checkElementAcceptable

checkElementAcceptable(element, store?): Promise<void>
Throws an error if the element is part of the initial elements given that the initial element store is provided
Parameters
- element: Uint8Array
- Optionalstore: IInitialElementsStore
Returns Promise<void>
- Defined in accumulator/accumulator.ts:982

checkElementBatchAcceptable

checkElementBatchAcceptable(elements, store?): Promise<void>
Throws an error if any element of the batch is part of the initial elements given that the initial element store is provided
Parameters
- elements: Uint8Array[]
- Optionalstore: IInitialElementsStore
Returns Promise<void>
- Defined in accumulator/accumulator.ts:996

`Protected`ensureAbsence

ensureAbsence(element, state?): Promise<void>
Protected
Check if element is absent in the state and throws an error if its present. Only checks if the state is passed
Parameters
- element: Uint8Array
- Optionalstate: IAccumulatorState
Returns Promise<void>
Inherited from Accumulator.ensureAbsence
- Defined in accumulator/accumulator.ts:298

`Protected`ensureAbsenceOfBatch

ensureAbsenceOfBatch(elements, state?): Promise<void>
Protected
Check if a batch of elements is absent in the state and throws an error any of them is present. Only checks if the state is passed
Parameters
- elements: Uint8Array[]
- Optionalstate: IAccumulatorState
Returns Promise<void>
Inherited from Accumulator.ensureAbsenceOfBatch
- Defined in accumulator/accumulator.ts:328

`Protected`ensurePresence

ensurePresence(element, state?): Promise<void>
Protected
Check if element is present in the state and throws an error if its absent. Only checks if the state is passed
Parameters
- element: Uint8Array
- Optionalstate: IAccumulatorState
Returns Promise<void>
Inherited from Accumulator.ensurePresence
- Defined in accumulator/accumulator.ts:313

`Protected`ensurePresenceOfBatch

ensurePresenceOfBatch(elements, state?): Promise<void>
Protected
Check if a batch of elements is present in the state and throws an error any of them is absent. Only checks if the state is passed
Parameters
- elements: Uint8Array[]
- Optionalstate: IAccumulatorState
Returns Promise<void>
Inherited from Accumulator.ensurePresenceOfBatch
- Defined in accumulator/accumulator.ts:342

`Protected`getParams

getParams(params?): AccumulatorParams
Return the params if provided as an argument else look for params on this.
Parameters
- Optionalparams: AccumulatorParams
Returns AccumulatorParams
params or throws error if cannot find params
Inherited from Accumulator.getParams
- Defined in accumulator/accumulator.ts:184

`Protected`getSecretKey

getSecretKey(secretKey?): AccumulatorSecretKey
Return the secret key if provided as an argument else look for secret key on this.
Parameters
- OptionalsecretKey: AccumulatorSecretKey
Returns AccumulatorSecretKey
secret key or throws error if cannot find secret key
Inherited from Accumulator.getSecretKey
- Defined in accumulator/accumulator.ts:169

membershipWitness

membershipWitness(member, secretKey?, state?, initialElementsStore?): Promise<VBMembershipWitness>
Calculate the membership witness for the given element
Parameters
- member: Uint8Array
- OptionalsecretKey: AccumulatorSecretKey
- Optionalstate: IAccumulatorState
  If state is provided it is checked for presence of the element before calculating the witness
- OptionalinitialElementsStore: IInitialElementsStore
Returns Promise<VBMembershipWitness>
Overrides Accumulator.membershipWitness
- Defined in accumulator/accumulator.ts:748

membershipWitnessesForBatch

membershipWitnessesForBatch(members, secretKey?, state?, initialElementsStore?): Promise<VBMembershipWitness[]>
Calculate the membership witnesses for the given batch of elements
Parameters
- members: Uint8Array[]
- OptionalsecretKey: AccumulatorSecretKey
- Optionalstate: IAccumulatorState
  If state is provided it is checked for presence of all the elements before calculating the witnesses
- OptionalinitialElementsStore: IInitialElementsStore
Returns Promise<VBMembershipWitness[]>
Overrides Accumulator.membershipWitnessesForBatch
- Defined in accumulator/accumulator.ts:761

nonMembershipWitness

nonMembershipWitness(nonMember, state, secretKey?, params?, initialElementsStore?, batchSize?): Promise<VBNonMembershipWitness>
Calculate the non-membership witness for the given element. The function takes time proportional to the current size of the accumulator as it takes the product of difference of all members and the non-member. To avoid taking too much memory, it breaks the computation into smaller batches.
Parameters
- nonMember: Uint8Array
- state: IUniversalAccumulatorState
- OptionalsecretKey: AccumulatorSecretKey
- Optionalparams: AccumulatorParams
- OptionalinitialElementsStore: IInitialElementsStore
- batchSize: number = 100
  Breaks down this large computation in batches of size batchSize.
Returns Promise<VBNonMembershipWitness>
- Defined in accumulator/accumulator.ts:786

nonMembershipWitnessesForBatch

nonMembershipWitnessesForBatch(nonMembers, state, secretKey?, params?, initialElementsStore?, batchSize?): Promise<VBNonMembershipWitness[]>
Calculate the non-membership witnesses for given batch of elements. The function takes time proportional to the current members and the number of non-members. To avoid taking too much memory, it breaks the computation into smaller batches.
Parameters
- nonMembers: Uint8Array[]
- state: IUniversalAccumulatorState
- OptionalsecretKey: AccumulatorSecretKey
- Optionalparams: AccumulatorParams
- OptionalinitialElementsStore: IInitialElementsStore
- batchSize: number = 100
  Breaks down this large computation in batches of size batchSize.
Returns Promise<VBNonMembershipWitness[]>
- Defined in accumulator/accumulator.ts:852

nonMembershipWitnessesForBatchGivenD

nonMembershipWitnessesForBatchGivenD(nonMembers, d, secretKey?, params?, state?, initialElementsStore?): Promise<VBNonMembershipWitness[]>
Calculate the non-membership witnesses for given batch of elements when the product of differences of all members and non-member (d) for each non-member is already computed.
Parameters
- nonMembers: Uint8Array[]
- d: Uint8Array[]
  array of products of difference of all members and each non-member
- OptionalsecretKey: AccumulatorSecretKey
- Optionalparams: AccumulatorParams
- Optionalstate: IUniversalAccumulatorState
- OptionalinitialElementsStore: IInitialElementsStore
Returns Promise<VBNonMembershipWitness[]>
- Defined in accumulator/accumulator.ts:911

nonMembershipWitnessGivenD

nonMembershipWitnessGivenD(nonMember, d, secretKey?, params?, state?, initialElementsStore?): Promise<VBNonMembershipWitness>
Calculate the non-membership witness for the given element when the product of differences of all members and non-member (d) is already computed.
Parameters
- nonMember: Uint8Array
- d: Uint8Array
  the product of difference of all members and the non-member.
- OptionalsecretKey: AccumulatorSecretKey
- Optionalparams: AccumulatorParams
- Optionalstate: IUniversalAccumulatorState
- OptionalinitialElementsStore: IInitialElementsStore
Returns Promise<VBNonMembershipWitness>
- Defined in accumulator/accumulator.ts:826

remove

remove(element, secretKey?, state?, initialElementsStore?): Promise<void>
Remove a single element from the accumulator
Parameters
- element: Uint8Array
- OptionalsecretKey: AccumulatorSecretKey
- Optionalstate: IAccumulatorState
  If state is provided it is checked before computing the new accumulator and element is removed from it after computing the new accumulator. Throws error if element is not present.
- OptionalinitialElementsStore: IInitialElementsStore
  if provided, check that the element is not part of the initial elements, throws error if it is.
Returns Promise<void>
Overrides Accumulator.remove
- Defined in accumulator/accumulator.ts:697

removeBatch

removeBatch(elements, secretKey?, state?, initialElementsStore?): Promise<void>
Remove a batch of elements from the accumulator.
Parameters
- elements: Uint8Array[]
- OptionalsecretKey: AccumulatorSecretKey
- Optionalstate: IAccumulatorState
  If state is provided it is checked before computing the new accumulator and updated by removing those elements after computing the new accumulator
- OptionalinitialElementsStore: IInitialElementsStore
Returns Promise<void>
Overrides Accumulator.removeBatch
- Defined in accumulator/accumulator.ts:721

`Protected`removeBatchFromState

removeBatchFromState(elements, state?): Promise<void>
Protected
If state is provided, remove the batch of elements from the state
Parameters
- elements: Uint8Array[]
- Optionalstate: IAccumulatorState
Returns Promise<void>
Inherited from Accumulator.removeBatchFromState
- Defined in accumulator/accumulator.ts:394

`Protected`removeFromState

removeFromState(element, state?): Promise<void>
Protected
If state is provided, remove the element from the state
Parameters
- element: Uint8Array
- Optionalstate: IAccumulatorState
Returns Promise<void>
Inherited from Accumulator.removeFromState
- Defined in accumulator/accumulator.ts:368

setNew

setNew(value): void
Parameters
- value: object | Uint8Array
Returns void
Inherited from Accumulator.setNew
- Defined in accumulator/accumulator.ts:76

toJSON

toJSON(): string
Returns string
- Defined in accumulator/accumulator.ts:1076

verifyMembershipWitness

verifyMembershipWitness(member, witness, pk, params?): boolean
Verify the membership witness.
Parameters
- member: Uint8Array
- witness: VBMembershipWitness
- pk: AccumulatorPublicKey
- Optionalparams: AccumulatorParams
Returns boolean
Overrides Accumulator.verifyMembershipWitness
- Defined in accumulator/accumulator.ts:928

verifyNonMembershipWitness

verifyNonMembershipWitness(nonMember, witness, pk, params?): boolean
Parameters
- nonMember: Uint8Array
- witness: VBNonMembershipWitness
- pk: AccumulatorPublicKey
- Optionalparams: AccumulatorParams
Returns boolean
- Defined in accumulator/accumulator.ts:938

`Static`combineInitialElementsProducts

combineInitialElementsProducts(products): Uint8Array
Parameters
- products: Uint8Array[]
Returns Uint8Array
- Defined in accumulator/accumulator.ts:965

`Static`dBatchForNonMembershipWitnesses

dBatchForNonMembershipWitnesses(nonMembers, members): Uint8Array[]
Parameters
- nonMembers: Uint8Array[]
- members: Uint8Array[]
Returns Uint8Array[]
- Defined in accumulator/accumulator.ts:973

`Static`deriveMembershipKeyFromNonMembershipProvingKey

deriveMembershipKeyFromNonMembershipProvingKey(nonMembershipKey): MembershipProvingKey
Parameters
- nonMembershipKey: NonMembershipProvingKey
Returns MembershipProvingKey
Inherited from Accumulator.deriveMembershipKeyFromNonMembershipProvingKey
- Defined in accumulator/accumulator.ts:158

`Static`dForNonMembershipWitness

dForNonMembershipWitness(nonMember, members): Uint8Array
Parameters
- nonMember: Uint8Array
- members: Uint8Array[]
Returns Uint8Array
- Defined in accumulator/accumulator.ts:969

`Static`encodeBytesAsAccumulatorMember

encodeBytesAsAccumulatorMember(bytes): Uint8Array
To add arbitrary bytes like byte representation of UUID or some other user id or something else as an accumulator member, encode it first using this. This is an irreversible encoding as a hash function is used to convert a message of arbitrary length to a fixed length encoding.
Parameters
- bytes: Uint8Array
Returns Uint8Array
Inherited from Accumulator.encodeBytesAsAccumulatorMember
- Defined in accumulator/accumulator.ts:86

`Static`encodePositiveNumberAsAccumulatorMember

encodePositiveNumberAsAccumulatorMember(num): Uint8Array
To add a positive number as an accumulator member, encode it first using this. Encodes a positive safe integer, i.e. of 53 bits
Parameters
- num: number
  should be a positive integer
Returns Uint8Array
Inherited from Accumulator.encodePositiveNumberAsAccumulatorMember
- Defined in accumulator/accumulator.ts:95

`Static`fixedInitialElements

fixedInitialElements(): Uint8Array[]
The first few members of a universal accumulator are fixed for each curve. These should be added to the curve before creating any witness and must never be removed.

Returns Uint8Array[]
- Defined in accumulator/accumulator.ts:952

`Static`fromAccumulated

fromAccumulated(accumulated): UniversalAccumulator
Parameters
- accumulated: Uint8Array
Returns UniversalAccumulator
- Defined in accumulator/accumulator.ts:1090

`Static`fromJSON

fromJSON(json): UniversalAccumulator
Parameters
- json: string
Returns UniversalAccumulator
- Defined in accumulator/accumulator.ts:1084

`Static`generateKeypair

generateKeypair(params, seed?): AccumulatorKeypair
Generate private and public key from given params and optional seed.
Parameters
- params: AccumulatorParams
- Optionalseed: Uint8Array
  Pass to generate keys deterministically.
Returns AccumulatorKeypair
Inherited from Accumulator.generateKeypair
- Defined in accumulator/accumulator.ts:136

`Static`generateMembershipProvingKey

generateMembershipProvingKey(label?): MembershipProvingKey
Generate proving key for proving membership in an accumulator in zero knowledge. Proving key is public data that must be known to both the prover and verifier. Any prover and verifier pair can mutually agree on a proving key and the manager does not need to be aware of any proving key.
Parameters
- Optionallabel: Uint8Array
  The bytearray that is hashed to deterministically generate the proving key.
Returns MembershipProvingKey
Inherited from Accumulator.generateMembershipProvingKey
- Defined in accumulator/accumulator.ts:146

`Static`generateNonMembershipProvingKey

generateNonMembershipProvingKey(label?): NonMembershipProvingKey
Generate proving key for proving non-membership in a universal accumulator in zero knowledge.
Parameters
- Optionallabel: Uint8Array
  The bytearray that is hashed to deterministically generate the proving key.
Returns NonMembershipProvingKey
Inherited from Accumulator.generateNonMembershipProvingKey
- Defined in accumulator/accumulator.ts:154

`Static`generateParams

generateParams(label?): AccumulatorParams
Generate accumulator parameters. They are needed to generate public key and initialize the accumulator.
Parameters
- Optionallabel: Uint8Array
  Pass to generate parameters deterministically.
Returns AccumulatorParams
Inherited from Accumulator.generateParams
- Defined in accumulator/accumulator.ts:104

`Static`generatePublicKeyFromSecretKey

generatePublicKeyFromSecretKey(secretKey, params): AccumulatorPublicKey
Generate public key from given params and secret key.
Parameters
- secretKey: AccumulatorSecretKey
- params: AccumulatorParams
Returns AccumulatorPublicKey
Inherited from Accumulator.generatePublicKeyFromSecretKey
- Defined in accumulator/accumulator.ts:123

`Static`generateSecretKey

generateSecretKey(seed?): AccumulatorSecretKey
Generate secret key for the accumulator manager who updates the accumulator and creates witnesses.
Parameters
- Optionalseed: Uint8Array
  Pass to generate key deterministically.
Returns AccumulatorSecretKey
Inherited from Accumulator.generateSecretKey
- Defined in accumulator/accumulator.ts:113

`Static`initialElementsProduct

initialElementsProduct(initialElements, secretKey): Uint8Array
Takes product of the form initial_element_i + secret_key.
Parameters
- initialElements: Uint8Array[]
- secretKey: AccumulatorSecretKey
Returns Uint8Array
- Defined in accumulator/accumulator.ts:961

`Static`initialize

initialize(maxSize, params, secretKey, initialElementsStore?, batchSize?): Promise<UniversalAccumulator>
Initialize a universal accumulator of the given maxSize. The function takes time proportional to maxSize as it generates about the same number of elements as the maxSize and takes their product in the end. These "initial elements" should not be added or removed from the accumulator.
Parameters
- maxSize: number
  Maximum members the accumulator can have at any instant.
- params: AccumulatorParams
- secretKey: AccumulatorSecretKey
- OptionalinitialElementsStore: IInitialElementsStore
  Optional, stores "initial elements" generated during initialization.
- batchSize: number = 100
  Breaks down this large computation in batches of size batchSize.
Returns Promise<UniversalAccumulator>
- Defined in accumulator/accumulator.ts:601

`Static`initializeGivenInitialElementsProduct

initializeGivenInitialElementsProduct(maxSize, initialElementsProduct, params, secretKey?): UniversalAccumulator
Assumes that the initial elements are generated and their product is taken, initialize the accumulator.
Parameters
- maxSize: number
- initialElementsProduct: Uint8Array
- params: AccumulatorParams
- OptionalsecretKey: AccumulatorSecretKey
Returns UniversalAccumulator
- Defined in accumulator/accumulator.ts:651

Class UniversalAccumulator

Hierarchy (view full)

Index

Constructors

Properties

Accessors

Methods

Constructors

constructor

Parameters

Returns UniversalAccumulator

Properties

params

secretKey

value

Accessors

accumulated

Returns Uint8Array

Methods

add

Parameters

Returns Promise<void>

addBatch

Parameters

Returns Promise<void>

ProtectedaddBatchToState

Parameters

Returns Promise<void>

addRemoveBatches

Parameters

Returns Promise<void>

ProtectedaddToState

Parameters

Returns Promise<void>

ProtectedcheckBeforeAdd

Parameters

Returns Promise<void>

ProtectedcheckBeforeAddBatch

Parameters

Returns Promise<void>

ProtectedcheckBeforeRemove

Parameters

Returns Promise<void>

ProtectedcheckBeforeRemoveBatch

Parameters

Returns Promise<void>

checkElementAcceptable

Parameters

Returns Promise<void>

checkElementBatchAcceptable

Parameters

Returns Promise<void>

ProtectedensureAbsence

Parameters

Returns Promise<void>

ProtectedensureAbsenceOfBatch

Parameters

Returns Promise<void>

ProtectedensurePresence

Parameters

Returns Promise<void>

ProtectedensurePresenceOfBatch

Parameters

Returns Promise<void>

ProtectedgetParams

Parameters

Returns AccumulatorParams

ProtectedgetSecretKey

Parameters

Returns AccumulatorSecretKey

membershipWitness

Parameters

Returns Promise<VBMembershipWitness>

membershipWitnessesForBatch

Parameters

Returns Promise<VBMembershipWitness[]>

nonMembershipWitness

Parameters

Returns Promise<VBNonMembershipWitness>

nonMembershipWitnessesForBatch

`Protected`addBatchToState

`Protected`addToState

`Protected`checkBeforeAdd

`Protected`checkBeforeAddBatch

`Protected`checkBeforeRemove

`Protected`checkBeforeRemoveBatch

`Protected`ensureAbsence

`Protected`ensureAbsenceOfBatch

`Protected`ensurePresence

`Protected`ensurePresenceOfBatch

`Protected`getParams

`Protected`getSecretKey

`Protected`removeBatchFromState

`Protected`removeFromState

`Static`combineInitialElementsProducts

`Static`dBatchForNonMembershipWitnesses

`Static`deriveMembershipKeyFromNonMembershipProvingKey

`Static`dForNonMembershipWitness

`Static`encodeBytesAsAccumulatorMember

`Static`encodePositiveNumberAsAccumulatorMember

`Static`fixedInitialElements

`Static`fromAccumulated

`Static`fromJSON

`Static`generateKeypair

`Static`generateMembershipProvingKey

`Static`generateNonMembershipProvingKey

`Static`generateParams

`Static`generatePublicKeyFromSecretKey