Crate blind_rsa_signatures 

Author-blinded RSASSA-PSS RSAE signatures.

This is an implementation of the RSA Blind Signatures (RFC 9474), based on the Zig implementation.

use blind_rsa_signatures::{KeyPair, Sha384, PSS, Randomized, DefaultRng};

// [SERVER]: Generate a RSA-2048 key pair
let kp = KeyPair::<Sha384, PSS, Randomized>::generate(&mut DefaultRng, 2048)?;
let (pk, sk) = (kp.pk, kp.sk);

// [CLIENT]: create a random message and blind it for the server whose public key is `pk`.
// The client must store the message and the secret.
let msg = b"test";
let blinding_result = pk.blind(&mut DefaultRng, msg)?;

// [SERVER]: compute a signature for a blind message, to be sent to the client.
// The client secret should not be sent to the server.
let blind_sig = sk.blind_sign(&blinding_result.blind_message)?;

// [CLIENT]: later, when the client wants to redeem a signed blind message,
// using the blinding secret, it can locally compute the signature of the
// original message.
// The client then owns a new valid (message, signature) pair, and the
// server cannot link it to a previous (blinded message, blind signature) pair.
// Note that the finalization function also verifies that the new signature
// is correct for the server public key.
let sig = pk.finalize(&blind_sig, &blinding_result, msg)?;

// [SERVER]: a non-blind signature can be verified using the server's public key.
pk.verify(&sig, blinding_result.msg_randomizer, msg)?;

Modules

reexports

Structs

BlindMessage

A blind message

BlindRsa

Blind RSA signatures with compile-time parameters.

BlindSignature

A blind signature

BlindingResult

Result of a blinding operation

DefaultRng

Default random number generator

Deterministic

Deterministic message preparation

KeyPair

An RSA key pair

MessageRandomizer

A message randomizer (noise added as a prefix to the message)

PSS

PSS mode with salt (salt length = hash output length)

PSSZero

PSS mode without salt (salt length = 0)

PublicKey

An RSA public key

Randomized

Randomized message preparation

Secret

A blinding secret factor

SecretKey

An RSA secret key

Sha256

SHA-256 hash algorithm

Sha384

SHA-384 hash algorithm

Sha512

SHA-512 hash algorithm

Signature

A (non-blind) signature

Enums

Error

Traits

HashAlgorithm

MessagePrepare

Trait for message preparation mode (compile-time parameter) The only valid implementations are Randomized and Deterministic.

SaltMode

Trait for PSS salt mode (compile-time parameter) The only valid implementations are PSS and PSSZero.

Type Aliases

BlindRsaKeyPair

Type alias for KeyPair with the same parameters as BlindRsa

BlindRsaPublicKey

Type alias for PublicKey with the same parameters as BlindRsa

BlindRsaSecretKey

Type alias for SecretKey with the same parameters as BlindRsa

BlindRsaSha384PSSDeterministic

RSABSSA-SHA384-PSS-Deterministic

BlindRsaSha384PSSRandomized

RSABSSA-SHA384-PSS-Randomized (RFC 9474 recommended)

BlindRsaSha384PSSZeroDeterministic

RSABSSA-SHA384-PSSZERO-Deterministic

BlindRsaSha384PSSZeroRandomized

RSABSSA-SHA384-PSSZERO-Randomized

KeyPairSha384PSSDeterministic

Key pair for RSABSSA-SHA384-PSS-Deterministic

KeyPairSha384PSSRandomized

Key pair for RSABSSA-SHA384-PSS-Randomized (RFC 9474 recommended)

KeyPairSha384PSSZeroDeterministic

Key pair for RSABSSA-SHA384-PSSZERO-Deterministic

KeyPairSha384PSSZeroRandomized

Key pair for RSABSSA-SHA384-PSSZERO-Randomized

PublicKeySha384PSSDeterministic

Public key for RSABSSA-SHA384-PSS-Deterministic

PublicKeySha384PSSRandomized

Public key for RSABSSA-SHA384-PSS-Randomized (RFC 9474 recommended)

PublicKeySha384PSSZeroDeterministic

Public key for RSABSSA-SHA384-PSSZERO-Deterministic

PublicKeySha384PSSZeroRandomized

Public key for RSABSSA-SHA384-PSSZERO-Randomized

SecretKeySha384PSSDeterministic

Secret key for RSABSSA-SHA384-PSS-Deterministic

SecretKeySha384PSSRandomized

Secret key for RSABSSA-SHA384-PSS-Randomized (RFC 9474 recommended)

SecretKeySha384PSSZeroDeterministic

Secret key for RSABSSA-SHA384-PSSZERO-Deterministic

SecretKeySha384PSSZeroRandomized

Secret key for RSABSSA-SHA384-PSSZERO-Randomized