https://github.com/noir-lang/noir_rsa

https://github.com/noir-lang/noir_rsa

Last synced: about 2 months ago
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• Host: GitHub
• URL: https://github.com/noir-lang/noir_rsa
• Owner: noir-lang
• License: apache-2.0
• Created: 2024-07-16T01:02:33.000Z (2 months ago)
• Default Branch: main
• Last Pushed: 2024-07-31T15:25:56.000Z (about 2 months ago)
• Last Synced: 2024-08-01T19:43:18.823Z (about 2 months ago)
• Language: Roff
• Size: 31.3 KB
• Stars: 12
• Watchers: 2
• Forks: 2
• Open Issues: 1
• Metadata Files:
  • Readme: README.md
  • License: LICENSE

Awesome Lists containing this project

• awesome-noir - RSA - RSA signature verification (Get Coding / Libraries)

README

        
# noir_rsa

Optimized Noir library that evaluates RSA signatures.

Uses https://github.com/zac-williamson/noir-bignum as a dependency.

NOTE: library requires noir v 0.32.0 or later. If using the barretenberg backend, bb version of at least 0.46.1 is required (`bbup -v 0.46.1 `)

# Usage

See tests in `lib.nr` for examples.

To construct a `BigNumInstance` objects, both the bignum modulus (the public key) and a Barrett reduction parameter are required as arrays of Field elements, with each element representing a 120-bit slice of the number.

See `signature_gen/src/main.rs` for how these parameters can be derived. The rust crate `noir-bignum-paramgen` contains both libraries and an executable that performs this formatting (https://crates.io/crates/noir-bignum-paramgen).

## Example Use

See tests in `lib.nr` for additional examples. The `pubkey_redc_param` parameter can be derived via the `noir-bignum-paramgen` tool and provided as a witness via Prover.toml

```rust

    use dep::noir_rsa::bignum::BigNum;

    use dep::noir_rsa::bignum::runtime_bignum::BigNumInstance;

    use dep::noir_rsa::bignum::fields::Params2048;

    use dep::noir_rsa::RSA;

    type BN2048 = BigNum<18, Params2048>;

    type BNInstance = BigNumInstance<18, Params2048>;

    type RSA2048 = RSA;

    fn verify_signature(pubkey: [u8; 256], signature: [u8; 256], pubkey_redc_param: BN2048)

        let sha256_hash: [u8; 32] = dep::std::hash::sha256("hello world".as_bytes());

        let modulus: BN2048 = BigNum::from_byte_be(pubkey);

        let signature: BN2048 = BigNum::from_byte_be(signature);

        let instance: BNInstance = BigNumInstance::new(modulus, pubkey_redc_param);

        let rsa: RSA2048 = RSA {};

        assert(rsa.verify_sha256_pkcs1v15(BNInstance, sha256_hash, signature));

    }

```

# Costs

Rough cost:

- 2,048 bit RSA: 26,888 gates per verification

- 1,024 bit RSA: 11,983 gates per verification

A circuit that verifies 1 signature (and does nothing else) will cost ~32k due to initialization costs of lookup tables