anya-core 1.2.0

//! Asymmetric Cryptography Module
//!
//! This module provides RSA and ECC implementations for the Bitcoin security framework.

use std::error::Error;

/// RSA key generation parameters
#[derive(Debug, Clone)]
pub struct RsaParams {
    /// Key size in bits
    pub key_size: usize,
    /// Public exponent
    pub exponent: u32,
}

impl Default for RsaParams {
    fn default() -> Self {
        Self {
            key_size: 2048,
            exponent: 65537, // Common value for e
        }
    }
}

/// Elliptic Curve parameters
#[derive(Debug, Clone)]
pub enum EcCurve {
    /// secp256k1 curve (used by Bitcoin)
    Secp256k1,
    /// P-256 curve
    P256,
    /// Curve25519
    Curve25519,
}

/// Asymmetric key pair
#[derive(Debug)]
pub struct KeyPair {
    /// Private key data
    pub private_key: Vec<u8>,
    /// Public key data
    pub public_key: Vec<u8>,
}

/// Generate an RSA key pair with the specified parameters
pub fn generate_rsa_keypair(params: &RsaParams) -> Result<KeyPair, Box<dyn Error>> {
    // Placeholder implementation
    // In a real implementation, we would use a crypto library like openssl, ring, etc.
    Ok(KeyPair {
        private_key: vec![0u8; params.key_size / 8],
        public_key: vec![0u8; params.key_size / 16],
    })
}

/// Generate an EC key pair with the specified curve
pub fn generate_ec_keypair(curve: &EcCurve) -> Result<KeyPair, Box<dyn Error>> {
    // Placeholder implementation
    // In a real implementation, we would use a crypto library like secp256k1, etc.
    let key_size = match curve {
        EcCurve::Secp256k1 => 32,
        EcCurve::P256 => 32,
        EcCurve::Curve25519 => 32,
    };

    Ok(KeyPair {
        private_key: vec![0u8; key_size],
        public_key: vec![0u8; key_size * 2],
    })
}

/// RSA encryption with PKCS1 padding
pub fn rsa_encrypt(_public_key: &[u8], data: &[u8]) -> Result<Vec<u8>, Box<dyn Error>> {
    // Placeholder implementation
    Ok(data.to_vec())
}

/// RSA decryption with PKCS1 padding
pub fn rsa_decrypt(_private_key: &[u8], data: &[u8]) -> Result<Vec<u8>, Box<dyn Error>> {
    // Placeholder implementation
    Ok(data.to_vec())
}

/// ECDH key agreement - derive a shared secret
pub fn ecdh_derive_secret(
    _private_key: &[u8],
    _peer_public_key: &[u8],
    _curve: &EcCurve,
) -> Result<Vec<u8>, Box<dyn Error>> {
    // Placeholder implementation
    Ok(vec![0u8; 32])
}