keyfork-shard: slightly improved error handling

This commit is contained in:
Ryan Heywood 2023-11-05 13:57:22 -06:00
parent 0768339487
commit 307941087a
Signed by: ryan
GPG Key ID: 8E401478A3FBEF72
6 changed files with 162 additions and 108 deletions

1
Cargo.lock generated
View File

@ -1073,6 +1073,7 @@ version = "0.1.0"
dependencies = [
"anyhow",
"bincode",
"card-backend",
"card-backend-pcsc",
"keyfork-derive-openpgp",
"keyfork-pinentry",

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@ -8,12 +8,13 @@ edition = "2021"
[features]
default = ["openpgp", "openpgp-card"]
openpgp = ["sequoia-openpgp", "prompt"]
openpgp-card = ["openpgp-card-sequoia", "card-backend-pcsc"]
openpgp-card = ["openpgp-card-sequoia", "card-backend-pcsc", "card-backend"]
prompt = ["keyfork-pinentry"]
[dependencies]
anyhow = "1.0.75"
bincode = "1.3.3"
card-backend = { version = "0.2.0", optional = true }
card-backend-pcsc = { version = "0.5.0", optional = true }
keyfork-derive-openpgp = { version = "0.1.0", path = "../keyfork-derive-openpgp" }
keyfork-pinentry = { version = "0.5.0", path = "../keyfork-pinentry", optional = true }

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@ -58,6 +58,11 @@ fn main() -> ExitCode {
let result = run();
if let Err(e) = result {
eprintln!("Error: {e}");
let mut source = e.source();
while let Some(new_error) = source.take() {
eprintln!("Source: {new_error}");
source = new_error.source();
}
return ExitCode::FAILURE;
}
ExitCode::SUCCESS

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@ -23,7 +23,7 @@ use openpgp::{
Marshal,
},
types::KeyFlags,
KeyID, PacketPile,
Fingerprint, KeyID, PacketPile,
};
pub use sequoia_openpgp as openpgp;
use sharks::{Share, Sharks};
@ -34,20 +34,43 @@ use keyring::Keyring;
mod smartcard;
use smartcard::SmartcardManager;
// TODO: better error handling
#[derive(Debug, thiserror::Error)]
pub enum Error {
#[error("Error with creating Share: {0}")]
Share(String),
#[derive(Debug, Clone)]
pub struct WrappedError(String);
#[error("Error combining shares: {0}")]
CombineShares(String),
impl std::fmt::Display for WrappedError {
fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
f.write_str(&self.0)
}
#[error("Derived secret hash {0} != expected {1}")]
InvalidSecret(Fingerprint, Fingerprint),
#[error("OpenPGP error: {0}")]
Sequoia(#[source] anyhow::Error),
#[error("OpenPGP IO error: {0}")]
SequoiaIo(#[source] std::io::Error),
#[error("Keyring error: {0}")]
Keyring(#[from] keyring::KeyringError),
#[error("Smartcard error: {0}")]
Smartcard(#[from] smartcard::SmartcardError),
#[error("IO error: {0}")]
Io(#[source] std::io::Error),
#[error("Derivation path: {0}")]
DerivationPath(#[from] keyfork_derive_openpgp::derive_util::path::Error),
#[error("Derivation request: {0}")]
DerivationRequest(#[from] keyfork_derive_openpgp::derive_util::request::DerivationError),
#[error("Keyfork OpenPGP: {0}")]
KeyforkOpenPGP(#[from] keyfork_derive_openpgp::Error),
}
impl std::error::Error for WrappedError {}
pub type Result<T, E = Box<dyn std::error::Error>> = std::result::Result<T, E>;
pub type Result<T, E = Error> = std::result::Result<T, E>;
#[derive(Debug, Clone)]
pub struct EncryptedMessage {
@ -71,24 +94,30 @@ impl EncryptedMessage {
for pkesk in &self.pkesks {
let mut packet = vec![];
pkesk.serialize(&mut packet)?;
pkesk.serialize(&mut packet).map_err(Error::Sequoia)?;
let message = Message::new(&mut packets);
let mut message = ArbitraryWriter::new(message, Tag::PKESK)?;
message.write_all(&packet)?;
message.finalize()?;
let mut message = ArbitraryWriter::new(message, Tag::PKESK).map_err(Error::Sequoia)?;
message.write_all(&packet).map_err(Error::SequoiaIo)?;
message.finalize().map_err(Error::Sequoia)?;
}
let mut packet = vec![];
self.message.serialize(&mut packet)?;
self.message
.serialize(&mut packet)
.map_err(Error::Sequoia)?;
let message = Message::new(&mut packets);
let mut message = ArbitraryWriter::new(message, Tag::SEIP)?;
message.write_all(&packet)?;
message.finalize()?;
let mut message = ArbitraryWriter::new(message, Tag::SEIP).map_err(Error::Sequoia)?;
message.write_all(&packet).map_err(Error::SequoiaIo)?;
message.finalize().map_err(Error::Sequoia)?;
let mut decryptor =
DecryptorBuilder::from_bytes(&packets)?.with_policy(policy, None, decryptor)?;
let mut decryptor = DecryptorBuilder::from_bytes(&packets)
.map_err(Error::Sequoia)?
.with_policy(policy, None, decryptor)
.map_err(Error::Sequoia)?;
let mut content = vec![];
decryptor.read_to_end(&mut content)?;
decryptor
.read_to_end(&mut content)
.map_err(Error::SequoiaIo)?;
Ok(content)
}
}
@ -98,18 +127,19 @@ pub fn discover_certs(path: impl AsRef<Path>) -> Result<Vec<Cert>> {
if path.is_file() {
let mut vec = vec![];
for cert in CertParser::from_file(path)? {
vec.push(cert?);
for cert in CertParser::from_file(path).map_err(Error::Sequoia)? {
vec.push(cert.map_err(Error::Sequoia)?);
}
Ok(vec)
} else {
let mut vec = vec![];
for entry in path
.read_dir()?
.read_dir()
.map_err(Error::Io)?
.filter_map(Result::ok)
.filter(|p| p.path().is_file())
{
vec.push(Cert::from_file(entry.path())?);
vec.push(Cert::from_file(entry.path()).map_err(Error::Sequoia)?);
}
Ok(vec)
}
@ -119,7 +149,10 @@ pub fn parse_messages(reader: impl Read + Send + Sync) -> Result<VecDeque<Encryp
let mut pkesks = Vec::new();
let mut encrypted_messages = VecDeque::new();
for packet in PacketPile::from_reader(reader)?.into_children() {
for packet in PacketPile::from_reader(reader)
.map_err(Error::Sequoia)?
.into_children()
{
match packet {
Packet::PKESK(p) => pkesks.push(p),
Packet::SEIP(s) => {
@ -186,13 +219,15 @@ pub fn combine(
metadata.decrypt_with(&policy, &mut keyring)?
};
let mut cert_parser = CertParser::from_bytes(&content)?;
let mut cert_parser = CertParser::from_bytes(&content).map_err(Error::Sequoia)?;
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<_>>>()?;
let certs = cert_parser
.collect::<openpgp::Result<Vec<_>>>()
.map_err(Error::Sequoia)?;
keyring.set_root_cert(root_cert.clone());
manager.set_root_cert(root_cert);
let mut messages: HashMap<KeyID, EncryptedMessage> =
@ -202,12 +237,14 @@ pub fn combine(
// 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?;
let valid_cert = valid_cert.map_err(Error::Sequoia)?;
// 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 secret_cert = secret_cert
.with_policy(&policy, None)
.map_err(Error::Sequoia)?;
let keys = get_decryption_keys(&secret_cert).collect::<Vec<_>>();
if !keys.is_empty() {
if let Some(message) = messages.get_mut(&valid_cert.keyid()) {
@ -252,7 +289,7 @@ pub fn combine(
.iter()
.map(|cert| cert.with_policy(&policy, None))
{
let valid_cert = valid_cert?;
let valid_cert = valid_cert.map_err(Error::Sequoia)?;
let fp = valid_cert
.keys()
.for_storage_encryption()
@ -282,8 +319,10 @@ pub fn combine(
.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)?;
.map_err(|e| Error::Share(e.to_string()))?;
let secret = Sharks(threshold)
.recover(&shares)
.map_err(|e| Error::CombineShares(e.to_string()))?;
let userid = UserID::from("keyfork-sss");
let kdr = DerivationRequest::new(
@ -298,19 +337,18 @@ pub fn combine(
)?;
// NOTE: Signatures on certs will be different. Compare fingerprints instead.
if Some(derived_cert.fingerprint()) != keyring.root_cert().map(Cert::fingerprint) {
return Err(WrappedError(format!(
"Derived {} != expected {}",
derived_cert.fingerprint(),
keyring
.root_cert()
.expect("cert was previously set")
.fingerprint()
))
.into());
let derived_fp = derived_cert.fingerprint();
let expected_fp = keyring
.root_cert()
.expect("cert was previously set")
.fingerprint();
if derived_fp != expected_fp {
return Err(Error::InvalidSecret(derived_fp, expected_fp));
}
output.write_all(smex::encode(&secret).as_bytes())?;
output
.write_all(smex::encode(&secret).as_bytes())
.map_err(Error::Io)?;
Ok(())
}
@ -330,23 +368,25 @@ pub fn split(threshold: u8, certs: Vec<Cert>, secret: &[u8], output: impl Write)
)?;
let signing_key = derived_cert
.primary_key()
.parts_into_secret()?
.parts_into_secret()
.map_err(Error::Sequoia)?
.key()
.clone()
.into_keypair()?;
.into_keypair()
.map_err(Error::Sequoia)?;
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 writer = Writer::new(output, Kind::Message).map_err(Error::SequoiaIo)?;
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 valid_cert = cert.with_policy(&policy, None).map_err(Error::Sequoia)?;
let encryption_keys = get_encryption_keys(&valid_cert).collect::<Vec<_>>();
let mut message_output = vec![];
@ -357,28 +397,34 @@ pub fn split(threshold: u8, certs: Vec<Cert>, secret: &[u8], output: impl Write)
.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()?;
.build()
.map_err(Error::Sequoia)?;
let message = Signer::new(message, signing_key.clone())
.build()
.map_err(Error::Sequoia)?;
let mut message = LiteralWriter::new(message)
.build()
.map_err(Error::Sequoia)?;
message.write_all(share).map_err(Error::SequoiaIo)?;
message.finalize().map_err(Error::Sequoia)?;
messages.push(message_output);
}
let mut pp = vec![];
// store derived cert to verify provided shares
derived_cert.serialize(&mut pp)?;
derived_cert.serialize(&mut pp).map_err(Error::Sequoia)?;
for recipient in &total_recipients {
recipient.serialize(&mut pp)?;
recipient.serialize(&mut pp).map_err(Error::Sequoia)?;
}
// verify packet pile
for (packet_cert, cert) in openpgp::cert::CertParser::from_bytes(&pp)?
for (packet_cert, cert) in openpgp::cert::CertParser::from_bytes(&pp)
.map_err(Error::Sequoia)?
.skip(1)
.zip(total_recipients.iter())
{
if packet_cert? != *cert {
if packet_cert.map_err(Error::Sequoia)? != *cert {
panic!(
"packet pile could not recreate cert: {}",
cert.fingerprint()
@ -389,7 +435,8 @@ pub fn split(threshold: u8, certs: Vec<Cert>, secret: &[u8], output: impl Write)
let valid_certs = total_recipients
.iter()
.map(|c| c.with_policy(&policy, None))
.collect::<openpgp::Result<Vec<_>>>()?;
.collect::<openpgp::Result<Vec<_>>>()
.map_err(Error::Sequoia)?;
let total_recipients = valid_certs.iter().flat_map(|vc| {
get_encryption_keys(vc).map(|key| Recipient::new(KeyID::wildcard(), key.key()))
@ -398,17 +445,23 @@ pub fn split(threshold: u8, certs: Vec<Cert>, secret: &[u8], output: impl Write)
// metadata
let mut message_output = vec![];
let message = Message::new(&mut message_output);
let message = Encryptor2::for_recipients(message, total_recipients).build()?;
let mut message = LiteralWriter::new(message).build()?;
message.write_all(&pp)?;
message.finalize()?;
writer.write_all(&message_output)?;
let message = Encryptor2::for_recipients(message, total_recipients)
.build()
.map_err(Error::Sequoia)?;
let mut message = LiteralWriter::new(message)
.build()
.map_err(Error::Sequoia)?;
message.write_all(&pp).map_err(Error::SequoiaIo)?;
message.finalize().map_err(Error::Sequoia)?;
writer
.write_all(&message_output)
.map_err(Error::SequoiaIo)?;
for message in messages {
writer.write_all(&message)?;
writer.write_all(&message).map_err(Error::SequoiaIo)?;
}
writer.finalize()?;
writer.finalize().map_err(Error::SequoiaIo)?;
Ok(())
}

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@ -9,27 +9,18 @@ use super::openpgp::{
KeyHandle, KeyID,
};
use crate::prompt_manager::PromptManager;
use crate::prompt_manager::{PromptManager, PinentryError};
#[derive(Clone, Debug)]
pub enum KeyringFailure {
#[derive(thiserror::Error, Debug)]
pub enum KeyringError {
#[error("Secret key was not found")]
SecretKeyNotFound,
#[allow(dead_code)]
SmartcardDecrypt,
#[error("Prompt failed: {0}")]
Prompt(#[from] PinentryError)
}
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 {}
pub type Result<T, E = KeyringError> = std::result::Result<T, E>;
pub struct Keyring {
full_certs: Vec<Cert>,
@ -38,7 +29,7 @@ pub struct Keyring {
}
impl Keyring {
pub fn new(certs: impl AsRef<[Cert]>) -> Result<Self, Box<dyn std::error::Error>> {
pub fn new(certs: impl AsRef<[Cert]>) -> Result<Self> {
Ok(Self {
full_certs: certs.as_ref().to_vec(),
root: Default::default(),
@ -164,6 +155,6 @@ impl DecryptionHelper for &mut Keyring {
}
}
Err(KeyringFailure::SecretKeyNotFound.into())
Err(KeyringError::SecretKeyNotFound.into())
}
}

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@ -9,27 +9,30 @@ use super::openpgp::{
parse::stream::{DecryptionHelper, MessageLayer, MessageStructure, VerificationHelper},
Fingerprint,
};
use crate::prompt_manager::PromptManager;
use crate::prompt_manager::{PinentryError, PromptManager};
use card_backend_pcsc::PcscBackend;
use openpgp_card_sequoia::{state::Open, Card};
#[derive(Clone, Debug)]
pub enum SmartcardFailure {
#[derive(thiserror::Error, Debug)]
pub enum SmartcardError {
#[error("No smart card backend was stored")]
SmartCardNotFound,
#[error("Selected smart card has no decryption key")]
SmartCardHasNoDecrypt,
#[error("Smart card backend error: {0}")]
SmartCardBackendError(#[from] card_backend::SmartcardError),
#[error("Smart card error: {0}")]
SmartCardEncounteredError(#[from] openpgp_card_sequoia::types::Error),
#[error("Prompt failed: {0}")]
Prompt(#[from] PinentryError),
}
impl std::fmt::Display for SmartcardFailure {
fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
match self {
Self::SmartCardNotFound => f.write_str("No smart card backend was stored"),
Self::SmartCardHasNoDecrypt => f.write_str("Selected smart card has no decrypt key"),
}
}
}
impl std::error::Error for SmartcardFailure {}
pub type Result<T, E = SmartcardError> = std::result::Result<T, E>;
fn format_name(input: impl AsRef<str>) -> String {
let mut n = input
@ -49,7 +52,7 @@ pub struct SmartcardManager {
}
impl SmartcardManager {
pub fn new() -> Result<Self, Box<dyn std::error::Error>> {
pub fn new() -> Result<Self> {
Ok(Self {
current_card: None,
root: None,
@ -65,20 +68,20 @@ impl SmartcardManager {
}
/// Load any backend.
pub fn load_any_card(&mut self) -> Result<Fingerprint, Box<dyn std::error::Error>> {
pub fn load_any_card(&mut self) -> Result<Fingerprint> {
PcscBackend::cards(None)?
.next()
.transpose()?
.ok_or(SmartcardFailure::SmartCardNotFound.into())
.ok_or(SmartcardError::SmartCardNotFound)
.and_then(
|backend| -> Result<Fingerprint, Box<dyn std::error::Error>> {
|backend| {
let mut card = Card::<Open>::new(backend)?;
let transaction = card.transaction()?;
let fingerprint = transaction
.fingerprints()?
.decryption()
.map(|fp| Fingerprint::from_bytes(fp.as_bytes()))
.ok_or(SmartcardFailure::SmartCardHasNoDecrypt)?;
.ok_or(SmartcardError::SmartCardHasNoDecrypt)?;
drop(transaction);
self.current_card.replace(card);
Ok(fingerprint)
@ -92,7 +95,7 @@ impl SmartcardManager {
pub fn load_any_fingerprint(
&mut self,
fingerprints: impl IntoIterator<Item = Fingerprint>,
) -> Result<Option<Fingerprint>, Box<dyn std::error::Error>> {
) -> Result<Option<Fingerprint>> {
// NOTE: This can't be HashSet::from_iter() because from_iter() requires a passed-in state
// I do not want to provide.
let mut requested_fingerprints = HashSet::new();
@ -178,7 +181,7 @@ impl DecryptionHelper for &mut SmartcardManager {
{
let mut card = self.current_card.take();
let Some(card) = card.as_mut() else {
return Err(SmartcardFailure::SmartCardNotFound.into());
return Err(SmartcardError::SmartCardNotFound.into());
};
let mut transaction = card.transaction()?;
@ -187,7 +190,7 @@ impl DecryptionHelper for &mut SmartcardManager {
.decryption()
.map(|fp| Fingerprint::from_bytes(fp.as_bytes()));
let Some(fp) = fp else {
return Err(SmartcardFailure::SmartCardHasNoDecrypt.into());
return Err(SmartcardError::SmartCardHasNoDecrypt.into());
};
let cardholder_name = format_name(transaction.cardholder_name()?);
let card_id = transaction.application_identifier()?.ident();
@ -210,6 +213,6 @@ impl DecryptionHelper for &mut SmartcardManager {
}
}
Err(SmartcardFailure::SmartCardNotFound.into())
Err(SmartcardError::SmartCardNotFound.into())
}
}