The secret key. More...

#include <keys.h>

Inheritance diagram for helib::SecKey:

Public Member Functions
	SecKey ()=delete

	~SecKey () override=default

	SecKey (const Context &_context)

bool	operator== (const SecKey &other) const

bool	operator!= (const SecKey &other) const

void	clear () override
	Clear all secret-key data. More...

long	ImportSecKey (const DoubleCRT &sKey, double bound, long ptxtSpace=0, long maxDegKswitch=3)

long	GenSecKey (long hwt=0, long ptxtSpace=0, long maxDegKswitch=3)

void	GenKeySWmatrix (long fromSPower, long fromXPower, long fromKeyIdx=0, long toKeyIdx=0, long ptxtSpace=0)

void	Decrypt (NTL::ZZX &plaintxt, const Ctxt &ciphertxt) const

template<typename Scheme >
void	Decrypt (Ptxt< Scheme > &plaintxt, const Ctxt &ciphertxt) const
	Decrypt a ciphertext into a plaintext. More...

void	Decrypt (NTL::ZZX &plaintxt, const Ctxt &ciphertxt, NTL::ZZX &f) const
	Debugging version, returns in f the polynomial before reduction modulo the ptxtSpace. More...

long	skEncrypt (Ctxt &ctxt, const NTL::ZZX &ptxt, long ptxtSpace, long skIdx) const
	Symmetric encryption using the secret key. More...

long	skEncrypt (Ctxt &ctxt, const zzX &ptxt, long ptxtSpace, long skIdx) const

long	Encrypt (Ctxt &ciphertxt, const NTL::ZZX &plaintxt, long ptxtSpace=0) const override

long	Encrypt (Ctxt &ciphertxt, const zzX &plaintxt, long ptxtSpace=0) const override

long	genRecryptData ()
	Generate bootstrapping data if needed, returns index of key. More...

friend	void ::helib::writeSecKeyBinary (std::ostream &str, const SecKey &sk)

friend	void ::helib::readSecKeyBinary (std::istream &str, SecKey &sk)

template<>
void	Decrypt (Ptxt< BGV > &plaintxt, const Ctxt &ciphertxt) const

template<>
void	Decrypt (Ptxt< CKKS > &plaintxt, const Ctxt &ciphertxt) const

Public Member Functions inherited from helib::PubKey
	PubKey ()
	This constructor thorws run-time error if activeContext=nullptr. More...

	PubKey (const Context &_context)

	PubKey (const PubKey &other)
	Copy constructor. More...

virtual	~PubKey ()=default
	Default destructor. More...

bool	operator== (const PubKey &other) const

bool	operator!= (const PubKey &other) const

const Context &	getContext () const

long	getPtxtSpace () const

bool	keyExists (long keyID) const

double	getSKeyBound (long keyID=0) const
	The size of the secret key. More...

bool	isReachable (long k, long keyID=0) const
	Is it possible to re-linearize the automorphism X -> X^k See Section 3.2.2 in the design document (KeySwitchMap) More...

void	setKeySwitchMap (long keyId=0)
	Compute the reachability graph of key-switching matrices See Section 3.2.2 in the design document (KeySwitchMap) More...

long	getKSStrategy (long dim) const
	get KS strategy for dimension dim dim == -1 is Frobenius More...

void	setKSStrategy (long dim, int val)
	set KS strategy for dimension dim dim == -1 is Frobenius More...

long	Encrypt (Ctxt &ciphertxt, const NTL::ZZX &plaintxt, long ptxtSpace, bool highNoise) const

long	Encrypt (Ctxt &ciphertxt, const zzX &plaintxt, long ptxtSpace, bool highNoise) const

void	CKKSencrypt (Ctxt &ciphertxt, const NTL::ZZX &plaintxt, double ptxtSize=1.0, double scaling=0.0) const

void	CKKSencrypt (Ctxt &ciphertxt, const zzX &plaintxt, double ptxtSize=1.0, double scaling=0.0) const

template<typename Scheme >
long	Encrypt (Ctxt &ciphertxt, const Ptxt< Scheme > &plaintxt, long ptxtSpace=0) const
	Encrypts a plaintext into a ciphertext. More...

double	securityLevel () const
	An estimate for the security level. The estimated security level for the "worst" secret-key associated with this public-key object. The security estimate is determined by the key's weight and the context parameters. More...

bool	isCKKS () const

bool	isBootstrappable () const

void	reCrypt (Ctxt &ctxt) const

void	thinReCrypt (Ctxt &ctxt) const

friend	void ::helib::writePubKeyBinary (std::ostream &str, const PubKey &pk)

friend	void ::helib::readPubKeyBinary (std::istream &str, PubKey &pk)

void	hackPtxtSpace (long p2r)

template<>
long	Encrypt (Ctxt &ciphertxt, const Ptxt< BGV > &plaintxt, long ptxtSpace) const

template<>
long	Encrypt (Ctxt &ciphertxt, const Ptxt< CKKS > &plaintxt, UNUSED long ptxtSpace) const

const std::vector< KeySwitch > &	keySWlist () const

const KeySwitch &	getKeySWmatrix (const SKHandle &from, long toID=0) const
	Find a key-switching matrix by its indexes. If no such matrix exists it returns a dummy matrix with toKeyID==-1. More...

const KeySwitch &	getKeySWmatrix (long fromSPower, long fromXPower, long fromID=0, long toID=0) const

bool	haveKeySWmatrix (const SKHandle &from, long toID=0) const

bool	haveKeySWmatrix (long fromSPower, long fromXPower, long fromID=0, long toID=0) const

const KeySwitch &	getAnyKeySWmatrix (const SKHandle &from) const
	Is there a matrix from this key to any base key? More...

bool	haveAnyKeySWmatrix (const SKHandle &from) const

const KeySwitch &	getNextKSWmatrix (long fromXPower, long fromID=0) const
	Get the next matrix to use for multi-hop automorphism See Section 3.2.2 in the design document. More...

Public Attributes
std::vector< DoubleCRT >	sKeys

Friends
std::ostream &	operator<< (std::ostream &str, const SecKey &sk)

std::istream &	operator>> (std::istream &str, SecKey &sk)

Additional Inherited Members
Static Public Member Functions inherited from helib::PubKey
static long	ePlusR (long p)

Detailed Description

The secret key.

Constructor & Destructor Documentation

◆ SecKey() [1/2]

helib::SecKey::SecKey ( )

delete

◆ ~SecKey()

helib::SecKey::~SecKey ( )

overridedefault

◆ SecKey() [2/2]

helib::SecKey::SecKey ( const Context & _context )

explicit

Member Function Documentation

◆ clear()

void helib::SecKey::clear ( )

overridevirtual

Clear all secret-key data.

Reimplemented from helib::PubKey.

◆ Decrypt() [1/5]

void helib::SecKey::Decrypt	(	NTL::ZZX &	plaintxt,
		const Ctxt &	ciphertxt
	)		const

◆ Decrypt() [2/5]

void helib::SecKey::Decrypt	(	NTL::ZZX &	plaintxt,
		const Ctxt &	ciphertxt,
		NTL::ZZX &	f
	)		const

Debugging version, returns in f the polynomial before reduction modulo the ptxtSpace.

◆ Decrypt() [3/5]

template<>

void helib::SecKey::Decrypt	(	Ptxt< BGV > &	plaintxt,
		const Ctxt &	ciphertxt
	)		const

◆ Decrypt() [4/5]

template<>

void helib::SecKey::Decrypt	(	Ptxt< CKKS > &	plaintxt,
		const Ctxt &	ciphertxt
	)		const

◆ Decrypt() [5/5]

template<typename Scheme >

void helib::SecKey::Decrypt	(	Ptxt< Scheme > &	plaintxt,
		const Ctxt &	ciphertxt
	)		const

Decrypt a ciphertext into a plaintext.

Template Parameters

Scheme Encryption scheme used (must be BGV or CKKS).

Parameters

plaintxt	Plaintext into which to decrypt.
ciphertxt	Ciphertext to decrypt.

◆ Encrypt() [1/2]

long helib::SecKey::Encrypt	(	Ctxt &	ciphertxt,
		const NTL::ZZX &	plaintxt,
		long	ptxtSpace = `0`
	)		const

overridevirtual

Reimplemented from helib::PubKey.

◆ Encrypt() [2/2]

long helib::SecKey::Encrypt	(	Ctxt &	ciphertxt,
		const zzX &	plaintxt,
		long	ptxtSpace = `0`
	)		const

overridevirtual

Reimplemented from helib::PubKey.

◆ GenKeySWmatrix()

void helib::SecKey::GenKeySWmatrix	(	long	fromSPower,
		long	fromXPower,
		long	fromKeyIdx = `0`,
		long	toKeyIdx = `0`,
		long	ptxtSpace = `0`
	)

Generate a key-switching matrix and store it in the public key. The i'th column of the matrix encrypts fromKey*B1*B2*...*B{i-1}*Q under toKey, relative to the largest modulus (i.e., all primes) and plaintext space p. Q is the product of special primes, and the Bi's are the products of primes in the i'th digit. The plaintext space defaults to 2^r, as defined by context.mod2r.

◆ genRecryptData()

long helib::SecKey::genRecryptData ( )

Generate bootstrapping data if needed, returns index of key.

◆ GenSecKey()

long helib::SecKey::GenSecKey	(	long	hwt = `0`,
		long	ptxtSpace = `0`,
		long	maxDegKswitch = `3`
	)

Key generation: This procedure generates a single secret key, pushes it onto the sKeys list using ImportSecKey from above.

◆ ImportSecKey()

long helib::SecKey::ImportSecKey	(	const DoubleCRT &	sKey,
		double	bound,
		long	ptxtSpace = `0`,
		long	maxDegKswitch = `3`
	)

We allow the calling application to choose a secret-key polynomial by itself, then insert it into the SecKey object, getting the index of that secret key in the sKeys list. If this is the first secret-key for this object then the procedure below also generates a corresponding public encryption key. It is assumed that the context already contains all parameters.

◆ operator!=()

bool helib::SecKey::operator!= ( const SecKey & other ) const

◆ operator==()

bool helib::SecKey::operator== ( const SecKey & other ) const

◆ skEncrypt() [1/2]

long helib::SecKey::skEncrypt	(	Ctxt &	ctxt,
		const NTL::ZZX &	ptxt,
		long	ptxtSpace,
		long	skIdx
	)		const

Symmetric encryption using the secret key.

◆ skEncrypt() [2/2]

long helib::SecKey::skEncrypt	(	Ctxt &	ctxt,
		const zzX &	ptxt,
		long	ptxtSpace,
		long	skIdx
	)		const

◆ void ::helib::readSecKeyBinary()

helib::SecKey::void ::helib::readSecKeyBinary	(	std::istream &	str,
		SecKey &	sk
	)

◆ void ::helib::writeSecKeyBinary()

helib::SecKey::void ::helib::writeSecKeyBinary	(	std::ostream &	str,
		const SecKey &	sk
	)

Friends And Related Function Documentation

◆ operator<<

std::ostream& operator<<	(	std::ostream &	str,
		const SecKey &	sk
	)

friend

◆ operator>>

std::istream& operator>>	(	std::istream &	str,
		SecKey &	sk
	)

friend

Member Data Documentation

◆ sKeys

std::vector<DoubleCRT> helib::SecKey::sKeys

Public Member Functions

Public Attributes

Friends

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

◆ SecKey() [1/2]

◆ ~SecKey()

◆ SecKey() [2/2]

Member Function Documentation

◆ clear()

◆ Decrypt() [1/5]

◆ Decrypt() [2/5]

◆ Decrypt() [3/5]

◆ Decrypt() [4/5]

◆ Decrypt() [5/5]

◆ Encrypt() [1/2]

◆ Encrypt() [2/2]

◆ GenKeySWmatrix()

◆ genRecryptData()

◆ GenSecKey()

◆ ImportSecKey()

◆ operator!=()

◆ operator==()

◆ skEncrypt() [1/2]

◆ skEncrypt() [2/2]

◆ void ::helib::readSecKeyBinary()

◆ void ::helib::writeSecKeyBinary()

Friends And Related Function Documentation

◆ operator<<

◆ operator>>

Member Data Documentation

◆ sKeys