HEaaN::KeyGenerator Class Reference

A class generating public (encryption/evaluation) keys from a secret key. More...

#include <KeyGenerator.hpp>

Collaboration diagram for HEaaN::KeyGenerator:

Public Member Functions
	KeyGenerator (const Context &context, const SecretKey &sk)
	Create a KeyGenerator object. More...
	KeyGenerator (const Context &context, const SecretKey &sk, const KeyPack &pack)
	Create a KeyGenerator object from an existing KeyPack object. More...
	KeyGenerator (const Context &context, const Context &context_sparse, const SecretKey &sk)
	Create a KeyGenerator object which can generate key that can perform sparse secret encapsulation, with the same parameter which context is constructed for. More...
	KeyGenerator (const Context &context, const Context &context_sparse, const SecretKey &sk, const KeyPack &pack)
	Create a KeyGenerator object from an existing pack object which can generate key that can which can perform sparse secret encapsulation, with the same parameter which context is constructed for. More...
void	genEncryptionKey (void) const
	Generate an encryption key into the internal KeyPack object. More...
void	genMultiplicationKey (void) const
	Generate a multiplication key into the internal KeyPack object. More...
void	genConjugationKey (void) const
	Generate a conjugation key into the internal KeyPack object. More...
void	genLeftRotationKey (u64 rot) const
	Generate a rotation key for the left rotation with rot steps, into the internal KeyPack object. More...
void	genRightRotationKey (u64 rot) const
	Generate a rotation key for the right rotation with rot steps, into the internal KeyPack object. More...
void	genRotationKeyBundle (void) const
	Generate a bundle of rotation keys. More...
void	genSparseSecretEncapsulationKey (void) const
	Generate a pair of keys for sparse secret encapsulation. More...
void	genCommonKeys (void) const
	Generate commonly used keys. More...
void	genRotKeysForBootstrap (const u64 log_slots) const
	Generate rotation keys used for accelerating the bootstrapping process. More...
void	save (const std::string &dir_path) const
	Save the generated keys in the internal KeyPack object into files. More...
void	flush (void)
	Discard current internal KeyPack object. More...
KeyPack	getKeyPack () const
	Extract the internal KeyPack object. More...

Private Attributes
const Context	context_
const std::optional< Context >	context_sparse_
KeyPack	pack_
	The internal keypack object. More...
std::shared_ptr< KeyGeneratorImpl >	impl_

Detailed Description

A class generating public (encryption/evaluation) keys from a secret key.

Constructor & Destructor Documentation

KeyGenerator() [1/4]

HEaaN::KeyGenerator::KeyGenerator ( const Context &  context, const SecretKey &  sk  )

explicit

Create a KeyGenerator object.

This generator internally creates a KeyPack object, which the user can later extract by getKeyPack() function. The SecretKey sk_ should have the same context as the input context context_. Otherwise, throws 'RuntimeException'.

KeyGenerator() [2/4]

HEaaN::KeyGenerator::KeyGenerator ( const Context &  context, const SecretKey &  sk, const KeyPack &  pack  )

explicit

Create a KeyGenerator object from an existing KeyPack object.

The SecretKey sk should have the same context as the input context context. Otherwise, throws 'RuntimeException'.

KeyGenerator() [3/4]

HEaaN::KeyGenerator::KeyGenerator ( const Context &  context, const Context &  context_sparse, const SecretKey &  sk  )

explicit

Create a KeyGenerator object which can generate key that can perform sparse secret encapsulation, with the same parameter which context is constructed for.

Exceptions

RuntimeException

if context_sparse is not a context constructed with the corresponding sparse parameter of which constructed context. Please refer to SparseParameterPresetFor() on ParameterPreset.hpp for the sparse parameters.

KeyGenerator() [4/4]

HEaaN::KeyGenerator::KeyGenerator ( const Context &  context, const Context &  context_sparse, const SecretKey &  sk, const KeyPack &  pack  )

explicit

Create a KeyGenerator object from an existing pack object which can generate key that can which can perform sparse secret encapsulation, with the same parameter which context is constructed for.

Exceptions

RuntimeException

if context_sparse is not a context constructed with the corresponding sparse parameter of context. Please refer to SparseParameterPresetFor() on ParameterPreset.hpp for the sparse parameters.

Member Function Documentation

flush()

void HEaaN::KeyGenerator::flush

(

void

)

Discard current internal KeyPack object.

genCommonKeys()

void HEaaN::KeyGenerator::genCommonKeys ( void  ) const

inline

Generate commonly used keys.

Be cautious that for bigger parameter sets, this function creates a lot of public keys in the internal KeyPack object, causing a high memory usage. In order to prevent this, the user might want to not use this function directly, and do use other key generation functions in the class separately, and use save() and flush() between the key generation.

genConjugationKey()

void HEaaN::KeyGenerator::genConjugationKey

(

void

)

const

Generate a conjugation key into the internal KeyPack object.

genEncryptionKey()

void HEaaN::KeyGenerator::genEncryptionKey

(

void

)

const

Generate an encryption key into the internal KeyPack object.

genLeftRotationKey()

void HEaaN::KeyGenerator::genLeftRotationKey

(

u64

rot

)

const

Generate a rotation key for the left rotation with rot steps, into the internal KeyPack object.

genMultiplicationKey()

void HEaaN::KeyGenerator::genMultiplicationKey

(

void

)

const

Generate a multiplication key into the internal KeyPack object.

genRightRotationKey()

void HEaaN::KeyGenerator::genRightRotationKey

(

u64

rot

)

const

Generate a rotation key for the right rotation with rot steps, into the internal KeyPack object.

genRotationKeyBundle()

void HEaaN::KeyGenerator::genRotationKeyBundle

(

void

)

const

Generate a bundle of rotation keys.

This function creates rotations keys for the left and right rotations with all power-of-two steps, so that any arbitrary rotation can be decomposed as a composition of these base rotations.

genRotKeysForBootstrap()

void HEaaN::KeyGenerator::genRotKeysForBootstrap

(

const u64

log_slots

)

const

Generate rotation keys used for accelerating the bootstrapping process.

Parameters

[in]

log_slots

This function generates only rotation keys. Bootstrapping process requires multiplication key and conjugation key, which are not generated in this function.

genSparseSecretEncapsulationKey()

void HEaaN::KeyGenerator::genSparseSecretEncapsulationKey

(

void

)

const

Generate a pair of keys for sparse secret encapsulation.

This function creates switching keys between the dense secret key and the sparse secret key so the sparse secret encapsulation can be performed during bootstrapping.

Exceptions

RuntimeException

getKeyPack()

KeyPack HEaaN::KeyGenerator::getKeyPack ( ) const

inline

Extract the internal KeyPack object.

Keys might be generated again into the keypack after this getter function is called.

save()

void HEaaN::KeyGenerator::save

(

const std::string &

dir_path

)

const

Save the generated keys in the internal KeyPack object into files.

Parameters

[in]

dir_path

must indicate a valid directory.

This function creates a subdirectory PK/ inside dirPath directory, and save all the keys in the cache of the KeyPack object into this subdirectory.

Member Data Documentation

context_

const Context HEaaN::KeyGenerator::context_

private

context_sparse_

const std::optional<Context> HEaaN::KeyGenerator::context_sparse_

private

impl_

std::shared_ptr<KeyGeneratorImpl> HEaaN::KeyGenerator::impl_

private

pack_

KeyPack HEaaN::KeyGenerator::pack_

private

The internal keypack object.

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The documentation for this class was generated from the following file:

• include/HEaaN/KeyGenerator.hpp