342 lines
11 KiB
Rust

use super::*;
use argon2::{
password_hash::{PasswordHash, PasswordHasher, PasswordVerifier, Salt, SaltString},
Argon2,
};
use chacha20::cipher::{KeyIvInit, StreamCipher};
use chacha20::XChaCha20;
use chacha20poly1305 as ch;
use chacha20poly1305::aead::{AeadInPlace, NewAead};
use core::convert::TryInto;
use curve25519_dalek as cd;
use digest::Digest;
use ed25519_dalek as ed;
use x25519_dalek as xd;
const AEAD_OVERHEAD: usize = 16;
pub const CRYPTO_KIND_VLD0: CryptoKind = FourCC([b'V', b'L', b'D', b'0']);
fn ed25519_to_x25519_pk(key: &ed::PublicKey) -> VeilidAPIResult<xd::PublicKey> {
let bytes = key.to_bytes();
let compressed = cd::edwards::CompressedEdwardsY(bytes);
let point = compressed
.decompress()
.ok_or_else(|| VeilidAPIError::internal("ed25519_to_x25519_pk failed"))?;
let mp = point.to_montgomery();
Ok(xd::PublicKey::from(mp.to_bytes()))
}
fn ed25519_to_x25519_sk(key: &ed::SecretKey) -> VeilidAPIResult<xd::StaticSecret> {
let exp = ed::ExpandedSecretKey::from(key);
let bytes: [u8; ed::EXPANDED_SECRET_KEY_LENGTH] = exp.to_bytes();
let lowbytes: [u8; 32] = bytes[0..32].try_into().map_err(VeilidAPIError::internal)?;
Ok(xd::StaticSecret::from(lowbytes))
}
pub fn vld0_generate_keypair() -> KeyPair {
let mut csprng = VeilidRng {};
let keypair = ed::Keypair::generate(&mut csprng);
let dht_key = PublicKey::new(keypair.public.to_bytes());
let dht_key_secret = SecretKey::new(keypair.secret.to_bytes());
KeyPair::new(dht_key, dht_key_secret)
}
/// V0 CryptoSystem
#[derive(Clone)]
pub struct CryptoSystemVLD0 {
crypto: Crypto,
}
impl CryptoSystemVLD0 {
pub fn new(crypto: Crypto) -> Self {
Self { crypto }
}
}
impl CryptoSystem for CryptoSystemVLD0 {
// Accessors
fn kind(&self) -> CryptoKind {
CRYPTO_KIND_VLD0
}
fn crypto(&self) -> Crypto {
self.crypto.clone()
}
// Cached Operations
fn cached_dh(&self, key: &PublicKey, secret: &SecretKey) -> VeilidAPIResult<SharedSecret> {
self.crypto
.cached_dh_internal::<CryptoSystemVLD0>(self, key, secret)
}
// Generation
fn random_bytes(&self, len: u32) -> Vec<u8> {
let mut bytes = unsafe { unaligned_u8_vec_uninit(len as usize) };
random_bytes(bytes.as_mut());
bytes
}
fn default_salt_length(&self) -> u32 {
16
}
fn hash_password(&self, password: &[u8], salt: &[u8]) -> VeilidAPIResult<String> {
if salt.len() < Salt::MIN_LENGTH || salt.len() > Salt::MAX_LENGTH {
apibail_generic!("invalid salt length");
}
// Hash password to PHC string ($argon2id$v=19$...)
let salt = SaltString::encode_b64(salt).map_err(VeilidAPIError::generic)?;
// Argon2 with default params (Argon2id v19)
let argon2 = Argon2::default();
let password_hash = argon2
.hash_password(password, &salt)
.map_err(VeilidAPIError::generic)?
.to_string();
Ok(password_hash)
}
fn verify_password(&self, password: &[u8], password_hash: &str) -> VeilidAPIResult<bool> {
let parsed_hash = PasswordHash::new(password_hash).map_err(VeilidAPIError::generic)?;
// Argon2 with default params (Argon2id v19)
let argon2 = Argon2::default();
Ok(argon2.verify_password(password, &parsed_hash).is_ok())
}
fn derive_shared_secret(&self, password: &[u8], salt: &[u8]) -> VeilidAPIResult<SharedSecret> {
if salt.len() < Salt::MIN_LENGTH || salt.len() > Salt::MAX_LENGTH {
apibail_generic!("invalid salt length");
}
// Argon2 with default params (Argon2id v19)
let argon2 = Argon2::default();
let mut output_key_material = [0u8; SHARED_SECRET_LENGTH];
argon2
.hash_password_into(password, salt, &mut output_key_material)
.map_err(VeilidAPIError::generic)?;
Ok(SharedSecret::new(output_key_material))
}
fn random_nonce(&self) -> Nonce {
let mut nonce = [0u8; NONCE_LENGTH];
random_bytes(&mut nonce);
Nonce::new(nonce)
}
fn random_shared_secret(&self) -> SharedSecret {
let mut s = [0u8; SHARED_SECRET_LENGTH];
random_bytes(&mut s);
SharedSecret::new(s)
}
fn compute_dh(&self, key: &PublicKey, secret: &SecretKey) -> VeilidAPIResult<SharedSecret> {
let pk_ed = ed::PublicKey::from_bytes(&key.bytes).map_err(VeilidAPIError::internal)?;
let pk_xd = ed25519_to_x25519_pk(&pk_ed)?;
let sk_ed = ed::SecretKey::from_bytes(&secret.bytes).map_err(VeilidAPIError::internal)?;
let sk_xd = ed25519_to_x25519_sk(&sk_ed)?;
Ok(SharedSecret::new(sk_xd.diffie_hellman(&pk_xd).to_bytes()))
}
fn generate_keypair(&self) -> KeyPair {
vld0_generate_keypair()
}
fn generate_hash(&self, data: &[u8]) -> PublicKey {
PublicKey::new(*blake3::hash(data).as_bytes())
}
fn generate_hash_reader(&self, reader: &mut dyn std::io::Read) -> VeilidAPIResult<PublicKey> {
let mut hasher = blake3::Hasher::new();
std::io::copy(reader, &mut hasher).map_err(VeilidAPIError::generic)?;
Ok(PublicKey::new(*hasher.finalize().as_bytes()))
}
// Validation
fn validate_keypair(&self, dht_key: &PublicKey, dht_key_secret: &SecretKey) -> bool {
let data = vec![0u8; 512];
let sig = match self.sign(dht_key, dht_key_secret, &data) {
Ok(s) => s,
Err(_) => {
return false;
}
};
self.verify(dht_key, &data, &sig).is_ok()
}
fn validate_hash(&self, data: &[u8], dht_key: &PublicKey) -> bool {
let bytes = *blake3::hash(data).as_bytes();
bytes == dht_key.bytes
}
fn validate_hash_reader(
&self,
reader: &mut dyn std::io::Read,
dht_key: &PublicKey,
) -> VeilidAPIResult<bool> {
let mut hasher = blake3::Hasher::new();
std::io::copy(reader, &mut hasher).map_err(VeilidAPIError::generic)?;
let bytes = *hasher.finalize().as_bytes();
Ok(bytes == dht_key.bytes)
}
// Distance Metric
fn distance(&self, key1: &PublicKey, key2: &PublicKey) -> CryptoKeyDistance {
let mut bytes = [0u8; PUBLIC_KEY_LENGTH];
for (n, byte) in bytes.iter_mut().enumerate() {
*byte = key1.bytes[n] ^ key2.bytes[n];
}
CryptoKeyDistance::new(bytes)
}
// Authentication
fn sign(
&self,
dht_key: &PublicKey,
dht_key_secret: &SecretKey,
data: &[u8],
) -> VeilidAPIResult<Signature> {
let mut kpb: [u8; SECRET_KEY_LENGTH + PUBLIC_KEY_LENGTH] =
[0u8; SECRET_KEY_LENGTH + PUBLIC_KEY_LENGTH];
kpb[..SECRET_KEY_LENGTH].copy_from_slice(&dht_key_secret.bytes);
kpb[SECRET_KEY_LENGTH..].copy_from_slice(&dht_key.bytes);
let keypair = ed::Keypair::from_bytes(&kpb)
.map_err(|e| VeilidAPIError::parse_error("Keypair is invalid", e))?;
let mut dig = Blake3Digest512::new();
dig.update(data);
let sig_bytes = keypair
.sign_prehashed(dig, None)
.map_err(VeilidAPIError::internal)?;
let sig = Signature::new(sig_bytes.to_bytes());
self.verify(dht_key, &data, &sig)?;
Ok(sig)
}
fn verify(
&self,
dht_key: &PublicKey,
data: &[u8],
signature: &Signature,
) -> VeilidAPIResult<()> {
let pk = ed::PublicKey::from_bytes(&dht_key.bytes)
.map_err(|e| VeilidAPIError::parse_error("Public key is invalid", e))?;
let sig = ed::Signature::from_bytes(&signature.bytes)
.map_err(|e| VeilidAPIError::parse_error("Signature is invalid", e))?;
let mut dig = Blake3Digest512::new();
dig.update(data);
pk.verify_prehashed(dig, None, &sig)
.map_err(|e| VeilidAPIError::parse_error("Verification failed", e))?;
Ok(())
}
// AEAD Encrypt/Decrypt
fn aead_overhead(&self) -> usize {
AEAD_OVERHEAD
}
fn decrypt_in_place_aead(
&self,
body: &mut Vec<u8>,
nonce: &Nonce,
shared_secret: &SharedSecret,
associated_data: Option<&[u8]>,
) -> VeilidAPIResult<()> {
let key = ch::Key::from(shared_secret.bytes);
let xnonce = ch::XNonce::from(nonce.bytes);
let aead = ch::XChaCha20Poly1305::new(&key);
aead.decrypt_in_place(&xnonce, associated_data.unwrap_or(b""), body)
.map_err(map_to_string)
.map_err(VeilidAPIError::generic)
}
fn decrypt_aead(
&self,
body: &[u8],
nonce: &Nonce,
shared_secret: &SharedSecret,
associated_data: Option<&[u8]>,
) -> VeilidAPIResult<Vec<u8>> {
let mut out = body.to_vec();
self.decrypt_in_place_aead(&mut out, nonce, shared_secret, associated_data)
.map_err(map_to_string)
.map_err(VeilidAPIError::generic)?;
Ok(out)
}
fn encrypt_in_place_aead(
&self,
body: &mut Vec<u8>,
nonce: &Nonce,
shared_secret: &SharedSecret,
associated_data: Option<&[u8]>,
) -> VeilidAPIResult<()> {
let key = ch::Key::from(shared_secret.bytes);
let xnonce = ch::XNonce::from(nonce.bytes);
let aead = ch::XChaCha20Poly1305::new(&key);
aead.encrypt_in_place(&xnonce, associated_data.unwrap_or(b""), body)
.map_err(map_to_string)
.map_err(VeilidAPIError::generic)
}
fn encrypt_aead(
&self,
body: &[u8],
nonce: &Nonce,
shared_secret: &SharedSecret,
associated_data: Option<&[u8]>,
) -> VeilidAPIResult<Vec<u8>> {
let mut out = body.to_vec();
self.encrypt_in_place_aead(&mut out, nonce, shared_secret, associated_data)
.map_err(map_to_string)
.map_err(VeilidAPIError::generic)?;
Ok(out)
}
// NoAuth Encrypt/Decrypt
fn crypt_in_place_no_auth(
&self,
body: &mut [u8],
nonce: &[u8; NONCE_LENGTH],
shared_secret: &SharedSecret,
) {
let mut cipher = XChaCha20::new(&shared_secret.bytes.into(), nonce.into());
cipher.apply_keystream(body);
}
fn crypt_b2b_no_auth(
&self,
in_buf: &[u8],
out_buf: &mut [u8],
nonce: &[u8; NONCE_LENGTH],
shared_secret: &SharedSecret,
) {
let mut cipher = XChaCha20::new(&shared_secret.bytes.into(), nonce.into());
cipher.apply_keystream_b2b(in_buf, out_buf).unwrap();
}
fn crypt_no_auth_aligned_8(
&self,
in_buf: &[u8],
nonce: &[u8; NONCE_LENGTH],
shared_secret: &SharedSecret,
) -> Vec<u8> {
let mut out_buf = unsafe { aligned_8_u8_vec_uninit(in_buf.len()) };
self.crypt_b2b_no_auth(in_buf, &mut out_buf, nonce, shared_secret);
out_buf
}
fn crypt_no_auth_unaligned(
&self,
in_buf: &[u8],
nonce: &[u8; NONCE_LENGTH],
shared_secret: &SharedSecret,
) -> Vec<u8> {
let mut out_buf = unsafe { unaligned_u8_vec_uninit(in_buf.len()) };
self.crypt_b2b_no_auth(in_buf, &mut out_buf, nonce, shared_secret);
out_buf
}
}