338 lines
10 KiB
Rust
338 lines
10 KiB
Rust
|
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(())
|
||
|
|
}
|