keyfork-shard: initial commit

This commit is contained in:
Ryan Heywood 2023-10-18 04:28:12 -05:00
parent 4cc3e11b0f
commit 31d1992e16
Signed by: ryan
GPG Key ID: 8E401478A3FBEF72
7 changed files with 730 additions and 2 deletions

78
Cargo.lock generated
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@ -17,6 +17,12 @@ version = "1.0.2"
source = "registry+https://github.com/rust-lang/crates.io-index" source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "f26201604c87b1e01bd3d98f8d5d9a8fcbb815e8cedb41ffccbeb4bf593a35fe" checksum = "f26201604c87b1e01bd3d98f8d5d9a8fcbb815e8cedb41ffccbeb4bf593a35fe"
[[package]]
name = "ahash"
version = "0.4.7"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "739f4a8db6605981345c5654f3a85b056ce52f37a39d34da03f25bf2151ea16e"
[[package]] [[package]]
name = "aho-corasick" name = "aho-corasick"
version = "1.0.4" version = "1.0.4"
@ -741,6 +747,15 @@ dependencies = [
"subtle", "subtle",
] ]
[[package]]
name = "hashbrown"
version = "0.9.1"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "d7afe4a420e3fe79967a00898cc1f4db7c8a49a9333a29f8a4bd76a253d5cd04"
dependencies = [
"ahash",
]
[[package]] [[package]]
name = "hashbrown" name = "hashbrown"
version = "0.14.1" version = "0.14.1"
@ -797,7 +812,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "8adf3ddd720272c6ea8bf59463c04e0f93d0bbf7c5439b691bca2987e0270897" checksum = "8adf3ddd720272c6ea8bf59463c04e0f93d0bbf7c5439b691bca2987e0270897"
dependencies = [ dependencies = [
"equivalent", "equivalent",
"hashbrown", "hashbrown 0.14.1",
] ]
[[package]] [[package]]
@ -948,6 +963,19 @@ dependencies = [
"smex", "smex",
] ]
[[package]]
name = "keyfork-shard"
version = "0.1.0"
dependencies = [
"anyhow",
"bincode",
"keyfork-derive-openpgp",
"sequoia-openpgp",
"serde",
"sharks",
"smex",
]
[[package]] [[package]]
name = "keyfork-slip10-test-data" name = "keyfork-slip10-test-data"
version = "0.1.0" version = "0.1.0"
@ -1376,11 +1404,22 @@ checksum = "6a6b1679d49b24bbfe0c803429aa1874472f50d9b363131f0e89fc356b544d03"
dependencies = [ dependencies = [
"getrandom 0.1.16", "getrandom 0.1.16",
"libc", "libc",
"rand_chacha", "rand_chacha 0.2.2",
"rand_core 0.5.1", "rand_core 0.5.1",
"rand_hc", "rand_hc",
] ]
[[package]]
name = "rand"
version = "0.8.5"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "34af8d1a0e25924bc5b7c43c079c942339d8f0a8b57c39049bef581b46327404"
dependencies = [
"libc",
"rand_chacha 0.3.1",
"rand_core 0.6.4",
]
[[package]] [[package]]
name = "rand_chacha" name = "rand_chacha"
version = "0.2.2" version = "0.2.2"
@ -1391,6 +1430,16 @@ dependencies = [
"rand_core 0.5.1", "rand_core 0.5.1",
] ]
[[package]]
name = "rand_chacha"
version = "0.3.1"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "e6c10a63a0fa32252be49d21e7709d4d4baf8d231c2dbce1eaa8141b9b127d88"
dependencies = [
"ppv-lite86",
"rand_core 0.6.4",
]
[[package]] [[package]]
name = "rand_core" name = "rand_core"
version = "0.3.1" version = "0.3.1"
@ -1697,6 +1746,17 @@ dependencies = [
"lazy_static", "lazy_static",
] ]
[[package]]
name = "sharks"
version = "0.5.0"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "902b1e955f8a2e429fb1bad49f83fb952e6195d3c360ac547ff00fb826388753"
dependencies = [
"hashbrown 0.9.1",
"rand 0.8.5",
"zeroize",
]
[[package]] [[package]]
name = "shlex" name = "shlex"
version = "1.2.0" version = "1.2.0"
@ -2332,3 +2392,17 @@ name = "zeroize"
version = "1.6.0" version = "1.6.0"
source = "registry+https://github.com/rust-lang/crates.io-index" source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "2a0956f1ba7c7909bfb66c2e9e4124ab6f6482560f6628b5aaeba39207c9aad9" checksum = "2a0956f1ba7c7909bfb66c2e9e4124ab6f6482560f6628b5aaeba39207c9aad9"
dependencies = [
"zeroize_derive",
]
[[package]]
name = "zeroize_derive"
version = "1.4.2"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "ce36e65b0d2999d2aafac989fb249189a141aee1f53c612c1f37d72631959f69"
dependencies = [
"proc-macro2",
"quote",
"syn 2.0.29",
]

View File

@ -10,6 +10,7 @@ members = [
"keyfork-frame", "keyfork-frame",
"keyfork-mnemonic-util", "keyfork-mnemonic-util",
"keyfork-plumbing", "keyfork-plumbing",
"keyfork-shard",
"keyfork-slip10-test-data", "keyfork-slip10-test-data",
"keyforkd", "keyforkd",
"keyforkd-client", "keyforkd-client",

15
keyfork-shard/Cargo.toml Normal file
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@ -0,0 +1,15 @@
[package]
name = "keyfork-shard"
version = "0.1.0"
edition = "2021"
# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
[dependencies]
anyhow = "1.0.75"
bincode = "1.3.3"
keyfork-derive-openpgp = { version = "0.1.0", path = "../keyfork-derive-openpgp" }
sequoia-openpgp = "1.16.1"
serde = "1.0.188"
sharks = "0.5.0"
smex = { version = "0.1.0", path = "../smex" }

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@ -0,0 +1,98 @@
use std::{
collections::VecDeque,
env,
io::{stdin, stdout},
path::PathBuf,
process::ExitCode,
str::FromStr,
};
use keyfork_shard::{combine, discover_certs, openpgp::Cert, EncryptedMessage};
use openpgp::{
packet::Packet,
parse::Parse,
PacketPile,
};
use sequoia_openpgp as openpgp;
#[derive(Clone, Debug)]
enum Error {
Usage(String),
}
impl std::fmt::Display for Error {
fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
match self {
Error::Usage(program_name) => {
write!(f, "Usage: {program_name} threshold key_discovery")
}
}
}
}
impl std::error::Error for Error {}
type Result<T, E = Box<dyn std::error::Error>> = std::result::Result<T, E>;
fn validate(threshold: &str, key_discovery: &str) -> Result<(u8, Vec<Cert>)> {
let threshold = u8::from_str(threshold)?;
let key_discovery = PathBuf::from(key_discovery);
// Verify path exists
std::fs::metadata(&key_discovery)?;
// Load certs from path
let certs = discover_certs(key_discovery)?;
Ok((threshold, certs))
}
fn run() -> Result<()> {
let mut args = env::args();
let program_name = args.next().expect("program name");
let args = args.collect::<Vec<_>>();
let (threshold, cert_list) = match args.as_slice() {
[threshold, key_discovery] => validate(threshold, key_discovery)?,
_ => return Err(Error::Usage(program_name).into()),
};
let stdin = stdin();
let mut pkesks = Vec::new();
let mut encrypted_messages = VecDeque::new();
for packet in PacketPile::from_reader(stdin)?.into_children() {
match packet {
Packet::PKESK(p) => pkesks.push(p),
Packet::SEIP(s) => {
encrypted_messages.push_back(EncryptedMessage::with_swap(&mut pkesks, s));
}
s => {
panic!("Invalid variant found: {}", s.tag());
}
}
}
let encrypted_metadata = encrypted_messages
.pop_front()
.expect("any pgp encrypted message");
combine(
threshold,
cert_list,
encrypted_metadata,
encrypted_messages.into(),
stdout(),
)?;
Ok(())
}
fn main() -> ExitCode {
let result = run();
if let Err(e) = result {
eprintln!("Error: {e}");
return ExitCode::FAILURE;
}
ExitCode::SUCCESS
}

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@ -0,0 +1,85 @@
use std::{env, path::PathBuf, process::ExitCode, str::FromStr};
use keyfork_shard::{discover_certs, openpgp::Cert, split};
#[derive(Clone, Debug)]
enum Error {
Usage(String),
Input,
Threshold(u8, u8),
InvalidCertCount(usize, u8),
}
impl std::fmt::Display for Error {
fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
match self {
Error::Usage(program_name) => {
write!(f, "Usage: {program_name} threshold max key_discovery")
}
Error::Input => f.write_str("Expected hex encoded input"),
Error::Threshold(threshold, max) => {
write!(
f,
"Invalid threshold: 0 < threshold {threshold} <= max {max} < 256"
)
}
Error::InvalidCertCount(count, max) => {
write!(f, "Invalid cert count: count {count} != max {max}")
}
}
}
}
impl std::error::Error for Error {}
type Result<T, E = Box<dyn std::error::Error>> = std::result::Result<T, E>;
fn validate(threshold: &str, max: &str, key_discovery: &str) -> Result<(u8, Vec<Cert>)> {
let threshold = u8::from_str(threshold)?;
let max = u8::from_str(max)?;
let key_discovery = PathBuf::from(key_discovery);
if threshold > max {
return Err(Error::Threshold(threshold, max).into());
}
// Verify path exists
std::fs::metadata(&key_discovery)?;
// Load certs from path
let certs = discover_certs(key_discovery)?;
if certs.len() != max.into() {
return Err(Error::InvalidCertCount(certs.len(), max).into());
}
Ok((threshold, certs))
}
fn run() -> Result<()> {
let mut args = env::args();
let program_name = args.next().expect("program name");
let args = args.collect::<Vec<_>>();
let (threshold, cert_list) = match args.as_slice() {
[threshold, max, key_discovery] => validate(threshold, max, key_discovery)?,
_ => return Err(Error::Usage(program_name).into()),
};
let input = {
use std::io::stdin;
let Some(line) = stdin().lines().next() else {
return Err(Error::Input.into());
};
smex::decode(&line?)?
};
split(threshold, cert_list, &input, std::io::stdout())?;
Ok(())
}
fn main() -> ExitCode {
let result = run();
if let Err(e) = result {
eprintln!("Error: {e}");
return ExitCode::FAILURE;
}
ExitCode::SUCCESS
}

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@ -0,0 +1,118 @@
use crate::openpgp::{
self,
cert::Cert,
packet::{PKESK, SKESK},
parse::stream::{DecryptionHelper, VerificationHelper, MessageStructure},
KeyHandle, KeyID,
};
#[derive(Clone, Debug)]
pub enum KeyringFailure {
SecretKeyNotFound,
#[allow(dead_code)]
SmartcardDecrypt,
}
impl std::fmt::Display for KeyringFailure {
fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
match self {
KeyringFailure::SecretKeyNotFound => f.write_str("Secret key was not found"),
KeyringFailure::SmartcardDecrypt => {
f.write_str("Smartcard could not decrypt any PKESKs")
}
}
}
}
impl std::error::Error for KeyringFailure {}
#[derive(Clone, Debug)]
pub struct Keyring {
full_certs: Vec<Cert>,
root: Option<Cert>,
}
impl Keyring {
pub fn new(certs: impl AsRef<[Cert]>) -> Self {
Self {
full_certs: certs.as_ref().to_vec(),
root: Default::default(),
}
}
// Sets the root cert, returning the old cert
pub fn set_root_cert(&mut self, cert: impl Into<Option<Cert>>) -> Option<Cert> {
let mut cert = cert.into();
std::mem::swap(&mut self.root, &mut cert);
cert
}
pub fn get_cert_for_primary_keyid<'a>(&'a self, keyid: &KeyID) -> Option<&'a Cert> {
self
.full_certs
.iter()
.find(|cert| &cert.keyid() == keyid)
}
// NOTE: This can't return an iterator because iterators are all different types
// and returning different types is naughty
fn get_certs_for_pkesk<'a>(&'a self, pkesk: &'a PKESK) -> impl Iterator<Item = &Cert> + 'a {
self.full_certs.iter().filter(move |cert| {
pkesk.recipient().is_wildcard()
|| cert.keys().any(|k| {
&k.keyid() == pkesk.recipient()
})
})
}
}
impl VerificationHelper for &mut Keyring {
fn get_certs(&mut self, _ids: &[KeyHandle]) -> openpgp::Result<Vec<Cert>> {
// TODO: no verification logic until we mark a cert as "root"
// this is the first cert in the metadata list
Ok(Vec::new())
}
fn check(&mut self, _structure: MessageStructure) -> openpgp::Result<()> {
// TODO: ensure that we have a "root" cert and assign it
Ok(())
}
}
impl DecryptionHelper for &mut Keyring {
fn decrypt<D>(
&mut self,
pkesks: &[PKESK],
_skesks: &[SKESK],
sym_algo: Option<openpgp::types::SymmetricAlgorithm>,
mut decrypt: D,
) -> openpgp::Result<Option<openpgp::Fingerprint>>
where
D: FnMut(
openpgp::types::SymmetricAlgorithm,
&openpgp::crypto::SessionKey,
) -> bool,
{
// optimized route: use all locally stored certs
for pkesk in pkesks {
for cert in self.get_certs_for_pkesk(pkesk) {
for key in cert.keys().secret() {
let secret_key = key.key().clone();
// NOTE: Returns an error if using an encrypted secret key.
// TODO: support skipping or validating encrypted secret keys.
let mut keypair = secret_key.into_keypair()?;
if pkesk
.decrypt(&mut keypair, sym_algo)
.map(|(algo, sk)| decrypt(algo, &sk))
.unwrap_or(false)
{
return Ok(Some(key.fingerprint()));
}
}
}
}
// smartcard route: plug in smartcard, attempt decrypt, fail and bail
Err(KeyringFailure::SecretKeyNotFound.into())
}
}

337
keyfork-shard/src/lib.rs Normal file
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@ -0,0 +1,337 @@
use std::{
collections::HashMap,
io::{Read, Write},
path::Path,
str::FromStr,
};
use keyfork_derive_openpgp::derive_util::{
request::{DerivationAlgorithm, DerivationRequest},
DerivationPath,
};
use openpgp::{
armor::{Kind, Writer},
cert::{Cert, CertParser, ValidCert},
packet::{Tag, UserID, PKESK, SEIP},
parse::{stream::DecryptorBuilder, Parse},
policy::{NullPolicy, Policy, StandardPolicy},
serialize::{
stream::{ArbitraryWriter, Encryptor, LiteralWriter, Message, Recipient, Signer},
Marshal,
},
types::KeyFlags,
KeyID,
};
pub use sequoia_openpgp as openpgp;
use sharks::{Share, Sharks};
mod keyring;
use keyring::Keyring;
// TODO: better error handling
#[derive(Debug, Clone)]
pub struct WrappedError(String);
impl std::fmt::Display for WrappedError {
fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
f.write_str(&self.0)
}
}
impl std::error::Error for WrappedError {}
pub type Result<T, E = Box<dyn std::error::Error>> = std::result::Result<T, E>;
#[derive(Debug, Clone)]
pub struct EncryptedMessage {
pkesks: Vec<PKESK>,
message: SEIP,
}
impl EncryptedMessage {
pub fn with_swap(pkesks: &mut Vec<PKESK>, seip: SEIP) -> Self {
Self {
pkesks: std::mem::take(pkesks),
message: seip,
}
}
pub fn decrypt_with(&self, policy: &'_ dyn Policy, keyring: &mut Keyring) -> Result<Vec<u8>> {
let mut packets = vec![];
for pkesk in &self.pkesks {
let mut packet = vec![];
pkesk.serialize(&mut packet)?;
let message = Message::new(&mut packets);
let mut message = ArbitraryWriter::new(message, Tag::PKESK)?;
message.write_all(&packet)?;
message.finalize()?;
}
let mut packet = vec![];
self.message.serialize(&mut packet)?;
let message = Message::new(&mut packets);
let mut message = ArbitraryWriter::new(message, Tag::SEIP)?;
message.write_all(&packet)?;
message.finalize()?;
/*
// TODO: only serialize the message and use provided PKESK vec
let mut pkesks = vec![];
let ppr = PacketParser::from_reader(&packets[..])?;
while let PacketParserResult::Some(mut pp) = ppr {
match pp.packet {
openpgp::Packet::PKESK(pkesk) => pkesks.push(pkesk),
openpgp::Packet::SEIP(_) => {
keyring.decrypt(&pkesks, &[], None, |algo, sk| {
// pushes packet to stack
pp.decrypt(algo, sk).is_ok()
});
},
p => panic!("Unexpected packet type: {}", p.tag()),
}
}
*/
let mut decryptor =
DecryptorBuilder::from_bytes(&packets)?.with_policy(policy, None, keyring)?;
let mut content = vec![];
decryptor.read_to_end(&mut content)?;
Ok(content)
}
}
pub fn discover_certs(path: impl AsRef<Path>) -> Result<Vec<Cert>> {
let path = path.as_ref();
if path.is_file() {
let mut vec = vec![];
for cert in CertParser::from_file(path)? {
vec.push(cert?);
}
Ok(vec)
} else {
let mut vec = vec![];
for entry in path
.read_dir()?
.filter_map(Result::ok)
.filter(|p| p.path().is_file())
{
vec.push(Cert::from_file(entry.path())?);
}
Ok(vec)
}
}
fn get_encryption_keys<'a>(
cert: &'a ValidCert,
) -> openpgp::cert::prelude::ValidKeyAmalgamationIter<
'a,
openpgp::packet::key::PublicParts,
openpgp::packet::key::UnspecifiedRole,
> {
cert.keys()
.alive()
.revoked(false)
.supported()
.for_storage_encryption()
}
fn get_decryption_keys<'a>(
cert: &'a ValidCert,
) -> openpgp::cert::prelude::ValidKeyAmalgamationIter<
'a,
openpgp::packet::key::SecretParts,
openpgp::packet::key::UnspecifiedRole,
> {
cert.keys()
/*
.alive()
.revoked(false)
.supported()
*/
.for_storage_encryption()
.secret()
}
pub fn combine(
threshold: u8,
certs: Vec<Cert>,
metadata: EncryptedMessage,
messages: Vec<EncryptedMessage>,
mut output: impl Write,
) -> Result<()> {
// Be as liberal as possible when decrypting.
// We don't want to invalidate someone's keys just because the old sig expired.
let policy = NullPolicy::new();
let mut keyring = Keyring::new(certs);
let content = metadata.decrypt_with(&policy, &mut keyring)?;
let mut cert_parser = CertParser::from_bytes(&content)?;
let root_cert = match cert_parser.next() {
Some(Ok(c)) => c,
Some(Err(e)) => panic!("Could not find root (first) certificate: {e}"),
None => panic!("No certs found in cert parser"),
};
let certs = cert_parser.collect::<openpgp::Result<Vec<_>>>()?;
keyring.set_root_cert(root_cert);
let mut messages: HashMap<KeyID, EncryptedMessage> =
HashMap::from_iter(certs.iter().map(|c| c.keyid()).zip(messages));
let mut decrypted_messages: HashMap<KeyID, Vec<u8>> = HashMap::new();
// NOTE: This is ONLY stable because we control the generation of PKESK packets and
// encode the policy to ourselves.
for valid_cert in certs.iter().map(|cert| cert.with_policy(&policy, None)) {
let valid_cert = valid_cert?;
// get keys from keyring for cert
let Some(secret_cert) = keyring.get_cert_for_primary_keyid(&valid_cert.keyid()) else {
continue;
};
let secret_cert = secret_cert.with_policy(&policy, None)?;
let keys = get_decryption_keys(&secret_cert).collect::<Vec<_>>();
if !keys.is_empty() {
if let Some(message) = messages.get_mut(&valid_cert.keyid()) {
for (pkesk, key) in message.pkesks.iter_mut().zip(keys) {
pkesk.set_recipient(key.keyid());
}
// we have a pkesk, decrypt via keyring
let result = message.decrypt_with(&policy, &mut keyring);
match result {
Ok(message) => {
decrypted_messages.insert(valid_cert.keyid(), message);
}
Err(e) => {
eprintln!(
"Could not decrypt with fingerprint {}: {}",
valid_cert.keyid(),
e
);
// do nothing, key will be retained
}
}
}
}
}
// clean decrypted messages from encrypted messages
messages.retain(|k, _v| !decrypted_messages.contains_key(k));
let left_from_threshold = threshold as usize - decrypted_messages.len();
if left_from_threshold > 0 {
eprintln!("remaining keys: {left_from_threshold}, prompting yubikeys");
}
for _ in 0..left_from_threshold {
todo!("prompt for Yubikeys")
}
let shares = decrypted_messages
.values()
.map(|message| Share::try_from(message.as_slice()))
.collect::<Result<Vec<_>, &str>>()
.map_err(|e| WrappedError(e.to_string()))?;
let secret = Sharks(threshold).recover(&shares)?;
output.write_all(smex::encode(&secret).as_bytes())?;
Ok(())
}
pub fn split(threshold: u8, certs: Vec<Cert>, secret: &[u8], output: impl Write) -> Result<()> {
// build cert to sign encrypted shares
let userid = UserID::from("keyfork-sss");
let kdr = DerivationRequest::new(
DerivationAlgorithm::Ed25519,
&DerivationPath::from_str("m/7366512'/0'")?,
)
.derive_with_master_seed(secret.to_vec())?;
let derived_cert = keyfork_derive_openpgp::derive(
kdr,
&[KeyFlags::empty().set_certification().set_signing()],
userid,
)?;
let signing_key = derived_cert
.primary_key()
.parts_into_secret()?
.key()
.clone()
.into_keypair()?;
let sharks = Sharks(threshold);
let dealer = sharks.dealer(secret);
let shares = dealer.map(|s| Vec::from(&s)).collect::<Vec<_>>();
let policy = StandardPolicy::new();
let mut writer = Writer::new(output, Kind::Message)?;
let mut total_recipients = vec![];
let mut messages = vec![];
for (share, cert) in shares.iter().zip(certs) {
total_recipients.push(cert.clone());
let valid_cert = cert.with_policy(&policy, None)?;
let encryption_keys = get_encryption_keys(&valid_cert).collect::<Vec<_>>();
let mut message_output = vec![];
let message = Message::new(&mut message_output);
let message = Encryptor::for_recipients(
message,
encryption_keys
.iter()
.map(|k| Recipient::new(KeyID::wildcard(), k.key())),
)
.build()?;
let message = Signer::new(message, signing_key.clone()).build()?;
let mut message = LiteralWriter::new(message).build()?;
message.write_all(share)?;
message.finalize()?;
messages.push(message_output);
}
let mut pp = vec![];
// store derived cert to verify provided shares
derived_cert.serialize(&mut pp)?;
for recipient in &total_recipients {
recipient.serialize(&mut pp)?;
}
// verify packet pile
for (packet_cert, cert) in openpgp::cert::CertParser::from_bytes(&pp)?
.skip(1)
.zip(total_recipients.iter())
{
if packet_cert? != *cert {
panic!(
"packet pile could not recreate cert: {}",
cert.fingerprint()
);
}
}
let valid_certs = total_recipients
.iter()
.map(|c| c.with_policy(&policy, None))
.collect::<openpgp::Result<Vec<_>>>()?;
let total_recipients = valid_certs.iter().flat_map(|vc| {
get_encryption_keys(vc).map(|key| Recipient::new(KeyID::wildcard(), key.key()))
});
// metadata
let mut message_output = vec![];
let message = Message::new(&mut message_output);
let message = Encryptor::for_recipients(message, total_recipients).build()?;
let mut message = LiteralWriter::new(message).build()?;
message.write_all(&pp)?;
message.finalize()?;
writer.write_all(&message_output)?;
for message in messages {
writer.write_all(&message)?;
}
writer.finalize()?;
Ok(())
}