virgil::crypto::pythia::VirgilPythia Class Reference

This class provides PYTHIA cryptographic functions and primitives. More...

#include <VirgilPythia.h>

Public Member Functions
VirgilPythiaBlindResult	blind (const VirgilByteArray &password)
	Blinds password. More...
VirgilByteArray	deblind (const VirgilByteArray &transformedPassword, const VirgilByteArray &blindingSecret)
	Deblinds transformedPassword value with previously returned blindingSecret from blind(). More...
VirgilPythiaTransformationKeyPair	computeTransformationKeyPair (const VirgilByteArray &transformationKeyID, const VirgilByteArray &pythiaSecret, const VirgilByteArray &pythiaScopeSecret)
	Computes transformation private and public key. More...
VirgilPythiaTransformResult	transform (const VirgilByteArray &blindedPassword, const VirgilByteArray &tweak, const VirgilByteArray &transformationPrivateKey)
	Transforms blinded password using the private key, generated from pythiaSecret + pythiaScopeSecret. More...
VirgilPythiaProveResult	prove (const VirgilByteArray &transformedPassword, const VirgilByteArray &blindedPassword, const VirgilByteArray &transformedTweak, const VirgilPythiaTransformationKeyPair &transformationKeyPair)
	Generates proof that server possesses secret values that were used to transform password. More...
bool	verify (const VirgilByteArray &transformedPassword, const VirgilByteArray &blindedPassword, const VirgilByteArray &tweak, const VirgilByteArray &transformationPublicKey, const VirgilByteArray &proofValueC, const VirgilByteArray &proofValueU)
	Verifies the output of transform(). More...
VirgilByteArray	getPasswordUpdateToken (const VirgilByteArray &previousTransformationPrivateKey, const VirgilByteArray &newTransformationPrivateKey)
	Computes update token. More...
VirgilByteArray	updateDeblindedWithToken (const VirgilByteArray &deblindedPassword, const VirgilByteArray &passwordUpdateToken)
	Updates previously stored deblindedPassword with passwordUpdateToken. More...

Detailed Description

This class provides PYTHIA cryptographic functions and primitives.

PYTHIA is a verifiable, cryptographic protocol that hardens passwords with the help of a remote service.

Member Function Documentation

VirgilPythiaBlindResult virgil::crypto::pythia::VirgilPythia::blind

(

const VirgilByteArray &

password

)

Blinds password.

Turns password into a pseudo-random string. This step is necessary to prevent 3rd-parties from knowledge of end user's password.

Parameters

password

- end user's password.

Returns

VirgilPythiaBlindResult

VirgilPythiaTransformationKeyPair virgil::crypto::pythia::VirgilPythia::computeTransformationKeyPair	(	const VirgilByteArray &	transformationKeyID,
		const VirgilByteArray &	pythiaSecret,
		const VirgilByteArray &	pythiaScopeSecret
	)

Computes transformation private and public key.

Parameters

transformationKeyID	- ensemble key ID used to enclose operations in subsets.
pythiaSecret	- global common for all secret random Key.
pythiaScopeSecret	- ensemble secret generated and versioned transparently.

Returns

VirgilPythiaTransformationKeyPair

VirgilByteArray virgil::crypto::pythia::VirgilPythia::deblind	(	const VirgilByteArray &	transformedPassword,
		const VirgilByteArray &	blindingSecret
	)

Deblinds transformedPassword value with previously returned blindingSecret from blind().

Parameters

transformedPassword	- GT transformed password from transform().
blindingSecret	- BN value that was generated in blind().

Returns

Deblinded transformedPassword value. This value is not equal to password and is zero-knowledge protected.

VirgilByteArray virgil::crypto::pythia::VirgilPythia::getPasswordUpdateToken	(	const VirgilByteArray &	previousTransformationPrivateKey,
		const VirgilByteArray &	newTransformationPrivateKey
	)

Computes update token.

Computes update token which allows update deblindedPassword when rotating transformation private key This action should increment version of pythiaScopeSecret.

Parameters

previousTransformationPrivateKey	- transformation private key
newTransformationPrivateKey	- new transformation private key

Returns

VirgilBteArray

VirgilPythiaProveResult virgil::crypto::pythia::VirgilPythia::prove	(	const VirgilByteArray &	transformedPassword,
		const VirgilByteArray &	blindedPassword,
		const VirgilByteArray &	transformedTweak,
		const VirgilPythiaTransformationKeyPair &	transformationKeyPair
	)

Generates proof that server possesses secret values that were used to transform password.

Parameters

transformedPassword	- GT transformed password from transform()
blindedPassword	- G1 blinded password from blind().
transformedTweak	- G2 transformed tweak from transform().
transformationKeyPair	- transformation key pair.

Returns

VirgilPythiaProveResult

VirgilPythiaTransformResult virgil::crypto::pythia::VirgilPythia::transform	(	const VirgilByteArray &	blindedPassword,
		const VirgilByteArray &	tweak,
		const VirgilByteArray &	transformationPrivateKey
	)

Transforms blinded password using the private key, generated from pythiaSecret + pythiaScopeSecret.

Parameters

blindedPassword	- G1 password obfuscated into a pseudo-random string.
tweak	- some random value used to identify user
transformationPrivateKey	- BN transformation private key.

Returns

VirgilPythiaTransformResult

VirgilByteArray virgil::crypto::pythia::VirgilPythia::updateDeblindedWithToken	(	const VirgilByteArray &	deblindedPassword,
		const VirgilByteArray &	passwordUpdateToken
	)

Updates previously stored deblindedPassword with passwordUpdateToken.

After this call, transform() called with new arguments will return corresponding values.

Parameters

deblindedPassword	- GT previous deblinded password from deblind().
passwordUpdateToken	- BN password update token from getPasswordUpdateToken().

Returns

New deblinded password.

bool virgil::crypto::pythia::VirgilPythia::verify	(	const VirgilByteArray &	transformedPassword,
		const VirgilByteArray &	blindedPassword,
		const VirgilByteArray &	tweak,
		const VirgilByteArray &	transformationPublicKey,
		const VirgilByteArray &	proofValueC,
		const VirgilByteArray &	proofValueU
	)

Verifies the output of transform().

This operation allows client to verify that the output of transform() is correct, assuming that client has previously stored tweak.

Parameters

transformedPassword	- GT transformed password from transform()
blindedPassword	- G1 blinded password from blind().
tweak	- tweak from transform()
transformationPublicKey	- G1 transformation public key
proofValueC	- BN proof value C from prove()
proofValueU	- BN proof value U from prove()

Returns

true if output of transform() is correct, false - otherwise.

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

• include/virgil/crypto/pythia/VirgilPythia.h