use std::time::Instant;
mod inbound_payment {
+ use alloc::string::ToString;
use bitcoin::hashes::{Hash, HashEngine};
use bitcoin::hashes::cmp::fixed_time_eq;
use bitcoin::hashes::hmac::{Hmac, HmacEngine};
use bitcoin::hashes::sha256::Hash as Sha256;
use chain::keysinterface::{KeyMaterial, KeysInterface, Sign};
use ln::{PaymentHash, PaymentPreimage, PaymentSecret};
+ use ln::channelmanager::APIError;
use ln::msgs;
use ln::msgs::MAX_VALUE_MSAT;
use util::chacha20::ChaCha20;
impl ExpandedKey {
pub(super) fn new(key_material: &KeyMaterial) -> ExpandedKey {
- hkdf_extract_expand(&vec![0], &key_material)
+ hkdf_extract_expand(b"LDK Inbound Payment Key Expansion", &key_material)
}
}
pub(super) fn verify<L: Deref>(payment_hash: PaymentHash, payment_data: msgs::FinalOnionHopData, highest_seen_timestamp: u64, keys: &ExpandedKey, logger: &L) -> Result<Option<PaymentPreimage>, ()>
where L::Target: Logger
{
- let mut iv_bytes = [0; IV_LEN];
- let (iv_slice, encrypted_metadata_bytes) = payment_data.payment_secret.0.split_at(IV_LEN);
- iv_bytes.copy_from_slice(iv_slice);
-
- let chacha_block = ChaCha20::get_single_block(&keys.metadata_key, &iv_bytes);
- let mut metadata_bytes: [u8; METADATA_LEN] = [0; METADATA_LEN];
- for i in 0..METADATA_LEN {
- metadata_bytes[i] = chacha_block[i] ^ encrypted_metadata_bytes[i];
- }
+ let (iv_bytes, metadata_bytes) = decrypt_metadata(payment_data.payment_secret, keys);
let payment_type_res = Method::from_bits((metadata_bytes[0] & 0b1110_0000) >> METHOD_TYPE_OFFSET);
let mut amt_msat_bytes = [0; AMT_MSAT_LEN];
}
},
Ok(Method::LdkPaymentHash) => {
- let mut hmac = HmacEngine::<Sha256>::new(&keys.ldk_pmt_hash_key);
- hmac.input(&iv_bytes);
- hmac.input(&metadata_bytes);
- let decoded_payment_preimage = Hmac::from_engine(hmac).into_inner();
- if !fixed_time_eq(&payment_hash.0, &Sha256::hash(&decoded_payment_preimage).into_inner()) {
- log_trace!(logger, "Failing HTLC with payment_hash {}: payment preimage {} did not match", log_bytes!(payment_hash.0), log_bytes!(decoded_payment_preimage));
- return Err(())
+ match derive_ldk_payment_preimage(payment_hash, &iv_bytes, &metadata_bytes, keys) {
+ Ok(preimage) => payment_preimage = Some(preimage),
+ Err(bad_preimage_bytes) => {
+ log_trace!(logger, "Failing HTLC with payment_hash {} due to mismatching preimage {}", log_bytes!(payment_hash.0), log_bytes!(bad_preimage_bytes));
+ return Err(())
+ }
}
- payment_preimage = Some(PaymentPreimage(decoded_payment_preimage));
},
Err(unknown_bits) => {
log_trace!(logger, "Failing HTLC with payment hash {} due to unknown payment type {}", log_bytes!(payment_hash.0), unknown_bits);
Ok(payment_preimage)
}
+ pub(super) fn get_payment_preimage(payment_hash: PaymentHash, payment_secret: PaymentSecret, keys: &ExpandedKey) -> Result<PaymentPreimage, APIError> {
+ let (iv_bytes, metadata_bytes) = decrypt_metadata(payment_secret, keys);
+
+ match Method::from_bits((metadata_bytes[0] & 0b1110_0000) >> METHOD_TYPE_OFFSET) {
+ Ok(Method::LdkPaymentHash) => {
+ derive_ldk_payment_preimage(payment_hash, &iv_bytes, &metadata_bytes, keys)
+ .map_err(|bad_preimage_bytes| APIError::APIMisuseError {
+ err: format!("Payment hash {} did not match decoded preimage {}", log_bytes!(payment_hash.0), log_bytes!(bad_preimage_bytes))
+ })
+ },
+ Ok(Method::UserPaymentHash) => Err(APIError::APIMisuseError {
+ err: "Expected payment type to be LdkPaymentHash, instead got UserPaymentHash".to_string()
+ }),
+ Err(other) => Err(APIError::APIMisuseError { err: format!("Unknown payment type: {}", other) }),
+ }
+ }
+
+ fn decrypt_metadata(payment_secret: PaymentSecret, keys: &ExpandedKey) -> ([u8; IV_LEN], [u8; METADATA_LEN]) {
+ let mut iv_bytes = [0; IV_LEN];
+ let (iv_slice, encrypted_metadata_bytes) = payment_secret.0.split_at(IV_LEN);
+ iv_bytes.copy_from_slice(iv_slice);
+
+ let chacha_block = ChaCha20::get_single_block(&keys.metadata_key, &iv_bytes);
+ let mut metadata_bytes: [u8; METADATA_LEN] = [0; METADATA_LEN];
+ for i in 0..METADATA_LEN {
+ metadata_bytes[i] = chacha_block[i] ^ encrypted_metadata_bytes[i];
+ }
+
+ (iv_bytes, metadata_bytes)
+ }
+
+ // Errors if the payment preimage doesn't match `payment_hash`. Returns the bad preimage bytes in
+ // this case.
+ fn derive_ldk_payment_preimage(payment_hash: PaymentHash, iv_bytes: &[u8; IV_LEN], metadata_bytes: &[u8; METADATA_LEN], keys: &ExpandedKey) -> Result<PaymentPreimage, [u8; 32]> {
+ let mut hmac = HmacEngine::<Sha256>::new(&keys.ldk_pmt_hash_key);
+ hmac.input(iv_bytes);
+ hmac.input(metadata_bytes);
+ let decoded_payment_preimage = Hmac::from_engine(hmac).into_inner();
+ if !fixed_time_eq(&payment_hash.0, &Sha256::hash(&decoded_payment_preimage).into_inner()) {
+ return Err(decoded_payment_preimage);
+ }
+ return Ok(PaymentPreimage(decoded_payment_preimage))
+ }
+
fn hkdf_extract_expand(salt: &[u8], ikm: &KeyMaterial) -> ExpandedKey {
let mut hmac = HmacEngine::<Sha256>::new(salt);
hmac.input(&ikm.0);
/// payment secret fetched via this method or [`create_inbound_payment`], and which is at least
/// the `min_value_msat` provided here, if one is provided.
///
- /// The [`PaymentHash`] (and corresponding [`PaymentPreimage`]) must be globally unique. This
- /// method may return an Err if another payment with the same payment_hash is still pending.
+ /// The [`PaymentHash`] (and corresponding [`PaymentPreimage`]) should be globally unique, though
+ /// note that LDK will not stop you from registering duplicate payment hashes for inbound
+ /// payments.
///
/// `min_value_msat` should be set if the invoice being generated contains a value. Any payment
/// received for the returned [`PaymentHash`] will be required to be at least `min_value_msat`
self.set_payment_hash_secret_map(payment_hash, None, min_value_msat, invoice_expiry_delta_secs)
}
+ /// Gets an LDK-generated payment preimage from a payment hash and payment secret that were
+ /// previously returned from [`create_inbound_payment`].
+ ///
+ /// [`create_inbound_payment`]: Self::create_inbound_payment
+ pub fn get_payment_preimage(&self, payment_hash: PaymentHash, payment_secret: PaymentSecret) -> Result<PaymentPreimage, APIError> {
+ inbound_payment::get_payment_preimage(payment_hash, payment_secret, &self.inbound_payment_key)
+ }
+
#[cfg(any(test, feature = "fuzztarget", feature = "_test_utils"))]
pub fn get_and_clear_pending_events(&self) -> Vec<events::Event> {
let events = core::cell::RefCell::new(Vec::new());
use chain::channelmonitor::{ANTI_REORG_DELAY, ChannelMonitor, LATENCY_GRACE_PERIOD_BLOCKS};
use chain::transaction::OutPoint;
use ln::channelmanager::{BREAKDOWN_TIMEOUT, ChannelManager, ChannelManagerReadArgs, PaymentId, PaymentSendFailure};
-use ln::features::InitFeatures;
+use ln::features::{InitFeatures, InvoiceFeatures};
use ln::msgs;
use ln::msgs::ChannelMessageHandler;
+use routing::router::{Payee, get_route};
use util::events::{ClosureReason, Event, MessageSendEvent, MessageSendEventsProvider};
use util::test_utils;
use util::errors::APIError;
// it had already considered the payment fulfilled, and now they just got free money.
assert!(nodes[0].node.get_and_clear_pending_events().is_empty());
}
+
+#[test]
+fn get_ldk_payment_preimage() {
+ // Ensure that `ChannelManager::get_payment_preimage` can successfully be used to claim a payment.
+ let chanmon_cfgs = create_chanmon_cfgs(2);
+ let node_cfgs = create_node_cfgs(2, &chanmon_cfgs);
+ let node_chanmgrs = create_node_chanmgrs(2, &node_cfgs, &[None, None]);
+ let mut nodes = create_network(2, &node_cfgs, &node_chanmgrs);
+ create_announced_chan_between_nodes(&nodes, 0, 1, InitFeatures::known(), InitFeatures::known());
+
+ let amt_msat = 60_000;
+ let expiry_secs = 60 * 60;
+ let (payment_hash, payment_secret) = nodes[1].node.create_inbound_payment(Some(amt_msat), expiry_secs).unwrap();
+
+ let payee = Payee::from_node_id(nodes[1].node.get_our_node_id())
+ .with_features(InvoiceFeatures::known());
+ let scorer = test_utils::TestScorer::with_fixed_penalty(0);
+ let route = get_route(
+ &nodes[0].node.get_our_node_id(), &payee, &nodes[0].network_graph,
+ Some(&nodes[0].node.list_usable_channels().iter().collect::<Vec<_>>()),
+ amt_msat, TEST_FINAL_CLTV, nodes[0].logger, &scorer).unwrap();
+ let _payment_id = nodes[0].node.send_payment(&route, payment_hash, &Some(payment_secret)).unwrap();
+ check_added_monitors!(nodes[0], 1);
+
+ // Make sure to use `get_payment_preimage`
+ let payment_preimage = nodes[1].node.get_payment_preimage(payment_hash, payment_secret).unwrap();
+ let mut events = nodes[0].node.get_and_clear_pending_msg_events();
+ assert_eq!(events.len(), 1);
+ pass_along_path(&nodes[0], &[&nodes[1]], amt_msat, payment_hash, Some(payment_secret), events.pop().unwrap(), true, Some(payment_preimage));
+ claim_payment_along_route(&nodes[0], &[&[&nodes[1]]], false, payment_preimage);
+}
projects / rust-lightning / commitdiff