Skip to content

Commit

Permalink
Decrypt Trampoline onions
Browse files Browse the repository at this point in the history 
In this commit, we start decrypting the inner onion we receive, and lay
some groundwork towards handling the subsequent routing or payment
receipt.
  • Loading branch information
@arik-so
arik-so committed Feb 28, 2025
1 parent 4a10d2a commit 392bc6d
Show file tree
Hide file tree
Showing 4 changed files with 459 additions and 32 deletions.
145 changes: 145 additions & 0 deletions lightning/src/ln/blinded_payment_tests.rs
View file
Original file line number Diff line number Diff line change
Expand Up @@ -39,6 +39,7 @@ use crate::util::test_utils;
use lightning_invoice::RawBolt11Invoice;
use types::features::Features;
use crate::blinded_path::BlindedHop;
use crate::routing::gossip::NodeId;

pub fn blinded_payment_path(
payment_secret: PaymentSecret, intro_node_min_htlc: u64, intro_node_max_htlc: u64,
Expand Down Expand Up @@ -1755,3 +1756,147 @@ fn test_combined_trampoline_onion_creation_vectors() {
assert_eq!(htlc_msat, 150_156_000);
assert_eq!(htlc_cltv, 800_060);
}

#[test]
#[cfg(trampoline)]
fn test_trampoline_inbound_payment_decoding() {
let secp_ctx = Secp256k1::new();
let session_priv = secret_from_hex("0303030303030303030303030303030303030303030303030303030303030303");

let bob_secret = secret_from_hex("4242424242424242424242424242424242424242424242424242424242424242");
let bob_node_id = PublicKey::from_secret_key(&secp_ctx, &bob_secret);
let _bob_unblinded_tlvs = bytes_from_hex("011a0000000000000000000000000000000000000000000000000000020800000000000006c10a0800240000009627100c06000b69e505dc0e00fd023103123456");
let carol_secret = secret_from_hex("4343434343434343434343434343434343434343434343434343434343434343");
let carol_node_id = PublicKey::from_secret_key(&secp_ctx, &carol_secret);
let _carol_unblinded_tlvs = bytes_from_hex("020800000000000004510821031b84c5567b126440995d3ed5aaba0565d71e1834604819ff9c17f5e9d5dd078f0a0800300000006401f40c06000b69c105dc0e00");
let dave_secret = secret_from_hex("4444444444444444444444444444444444444444444444444444444444444444");
let dave_node_id = PublicKey::from_secret_key(&secp_ctx, &dave_secret);
let _dave_unblinded_tlvs = bytes_from_hex("01230000000000000000000000000000000000000000000000000000000000000000000000020800000000000002310a060090000000fa0c06000b699105dc0e00");
let eve_secret = secret_from_hex("4545454545454545454545454545454545454545454545454545454545454545");
let _eve_node_id = PublicKey::from_secret_key(&secp_ctx, &eve_secret);
let _eve_unblinded_tlvs = bytes_from_hex("011a00000000000000000000000000000000000000000000000000000604deadbeef0c06000b690105dc0e0f020000000000000000000000000000fdffff0206c1");

let path = Path {
hops: vec![
// Bob
RouteHop {
pubkey: bob_node_id,
node_features: NodeFeatures::empty(),
short_channel_id: 0,
channel_features: ChannelFeatures::empty(),
fee_msat: 0,
cltv_expiry_delta: 0,
maybe_announced_channel: false,
},

// Carol
RouteHop {
pubkey: carol_node_id,
node_features: NodeFeatures::empty(),
short_channel_id: (572330 << 40) + (42 << 16) + 2821,
channel_features: ChannelFeatures::empty(),
fee_msat: 150_153_000,
cltv_expiry_delta: 0,
maybe_announced_channel: false,
},
],
blinded_tail: Some(BlindedTail {
trampoline_hops: vec![
// Carol's pubkey
TrampolineHop {
pubkey: carol_node_id,
node_features: Features::empty(),
fee_msat: 2_500,
cltv_expiry_delta: 24,
},
// Dave's pubkey (the intro node needs to be duplicated)
TrampolineHop {
pubkey: dave_node_id,
node_features: Features::empty(),
fee_msat: 150_500, // incorporate both base and proportional fee
cltv_expiry_delta: 36,
}
],
hops: vec![
// Dave's blinded node id
BlindedHop {
blinded_node_id: pubkey_from_hex("0295d40514096a8be54859e7dfe947b376eaafea8afe5cb4eb2c13ff857ed0b4be"),
encrypted_payload: bytes_from_hex("0ccf3c8a58deaa603f657ee2a5ed9d604eb5c8ca1e5f801989afa8f3ea6d789bbdde2c7e7a1ef9ca8c38d2c54760febad8446d3f273ddb537569ef56613846ccd3aba78a"),
},
// Eve's blinded node id
BlindedHop {
blinded_node_id: pubkey_from_hex("020e2dbadcc2005e859819ddebbe88a834ae8a6d2b049233c07335f15cd1dc5f22"),
encrypted_payload: bytes_from_hex("bcd747394fbd4d99588da075a623316e15a576df5bc785cccc7cd6ec7b398acce6faf520175f9ec920f2ef261cdb83dc28cc3a0eeb970107b3306489bf771ef5b1213bca811d345285405861d08a655b6c237fa247a8b4491beee20c878a60e9816492026d8feb9dafa84585b253978db6a0aa2945df5ef445c61e801fb82f43d5f00716baf9fc9b3de50bc22950a36bda8fc27bfb1242e5860c7e687438d4133e058770361a19b6c271a2a07788d34dccc27e39b9829b061a4d960eac4a2c2b0f4de506c24f9af3868c0aff6dda27281c"),
}
],
blinding_point: pubkey_from_hex("02988face71e92c345a068f740191fd8e53be14f0bb957ef730d3c5f76087b960e"),
excess_final_cltv_expiry_delta: 0,
final_value_msat: 150_000_000
})
};

let payment_secret = PaymentSecret(secret_from_hex("7494b65bc092b48a75465e43e29be807eb2cc535ce8aaba31012b8ff1ceac5da").secret_bytes());

let amt_msat = 150_000_001;
let cur_height = 800_001;
let recipient_onion_fields = RecipientOnionFields::secret_only(payment_secret);
let (bob_onion, _, _) = onion_utils::create_payment_onion(&secp_ctx, &path, &session_priv, amt_msat, &recipient_onion_fields, cur_height, &PaymentHash([0; 32]), &None, None, [0; 32]).unwrap();

struct TestEcdhSigner {
node_secret: SecretKey,
}
impl NodeSigner for TestEcdhSigner {
fn ecdh(
&self, _recipient: Recipient, other_key: &PublicKey, tweak: Option<&Scalar>,
) -> Result<SharedSecret, ()> {
let mut node_secret = self.node_secret.clone();
if let Some(tweak) = tweak {
node_secret = self.node_secret.mul_tweak(tweak).map_err(|_| ())?;
}
Ok(SharedSecret::new(other_key, &node_secret))
}
fn get_inbound_payment_key(&self) -> ExpandedKey { unreachable!() }
fn get_node_id(&self, _recipient: Recipient) -> Result<PublicKey, ()> { unreachable!() }
fn sign_invoice(
&self, _invoice: &RawBolt11Invoice, _recipient: Recipient,
) -> Result<RecoverableSignature, ()> { unreachable!() }
fn sign_bolt12_invoice(
&self, _invoice: &UnsignedBolt12Invoice,
) -> Result<schnorr::Signature, ()> { unreachable!() }
fn sign_gossip_message(&self, _msg: UnsignedGossipMessage) -> Result<Signature, ()> { unreachable!() }
}
let logger = test_utils::TestLogger::with_id("".to_owned());

let bob_update_add = update_add_msg(111_000, 747_501, None, bob_onion);
let bob_node_signer = TestEcdhSigner { node_secret: bob_secret };

let (bob_peeled_onion, next_packet_details_opt) = onion_payment::decode_incoming_update_add_htlc_onion(
&bob_update_add, &bob_node_signer, &logger, &secp_ctx
).unwrap_or_else(|_| panic!());

let (carol_packet_bytes, carol_hmac) = if let onion_utils::Hop::Forward {
next_hop_data: msgs::InboundOnionForwardPayload {..}, next_hop_hmac, new_packet_bytes, ..
} = bob_peeled_onion {
(new_packet_bytes, next_hop_hmac)
} else { panic!() };

let carol_packet_details = next_packet_details_opt.unwrap();
let carol_onion = msgs::OnionPacket {
version: 0,
public_key: carol_packet_details.next_packet_pubkey,
hop_data: carol_packet_bytes,
hmac: carol_hmac,
};
let carol_update_add = update_add_msg(carol_packet_details.outgoing_amt_msat, carol_packet_details.outgoing_cltv_value, None, carol_onion);

let carol_node_signer = TestEcdhSigner { node_secret: carol_secret };
let (carol_peeled_onion, _) = onion_payment::decode_incoming_update_add_htlc_onion(
&carol_update_add, &carol_node_signer, &logger, &secp_ctx
).unwrap_or_else(|_| panic!());

let _carol_trampoline_update_add = if let onion_utils::Hop::TrampolineForward { next_trampoline_hop_data, .. } = carol_peeled_onion {
assert_eq!(next_trampoline_hop_data.outgoing_node_id, NodeId::from_pubkey(&dave_node_id));
} else {
panic!();
};
}
27 changes: 26 additions & 1 deletion lightning/src/ln/channelmanager.rs
View file
Original file line number Diff line number Diff line change
Expand Up @@ -4479,11 +4479,36 @@ where
Err(InboundHTLCErr { err_code, err_data, msg }) => return_err!(msg, err_code, &err_data)
}
},
#[cfg(trampoline)]
onion_utils::Hop::TrampolineReceive { .. } => {
// OUR PAYMENT!
let current_height: u32 = self.best_block.read().unwrap().height;
match create_recv_pending_htlc_info(decoded_hop, shared_secret, msg.payment_hash,
msg.amount_msat, msg.cltv_expiry, None, allow_underpay, msg.skimmed_fee_msat,
current_height)
{
Ok(info) => {
// Note that we could obviously respond immediately with an update_fulfill_htlc
// message, however that would leak that we are the recipient of this payment, so
// instead we stay symmetric with the forwarding case, only responding (after a
// delay) once they've sent us a commitment_signed!
PendingHTLCStatus::Forward(info)
},
Err(InboundHTLCErr { err_code, err_data, msg }) => return_err!(msg, err_code, &err_data)
}
},
onion_utils::Hop::Forward { .. } | onion_utils::Hop::BlindedForward { .. } => {
match create_fwd_pending_htlc_info(msg, decoded_hop, shared_secret, next_packet_pubkey_opt) {
Ok(info) => PendingHTLCStatus::Forward(info),
Err(InboundHTLCErr { err_code, err_data, msg }) => return_err!(msg, err_code, &err_data)
}
},
#[cfg(trampoline)]
onion_utils::Hop::TrampolineForward { .. } | onion_utils::Hop::TrampolineBlindedForward { .. } => {
match create_fwd_pending_htlc_info(msg, decoded_hop, shared_secret, next_packet_pubkey_opt) {
Ok(info) => PendingHTLCStatus::Forward(info),
Err(InboundHTLCErr { err_code, err_data, msg }) => return_err!(msg, err_code, &err_data)
}
}
}
}
Expand Down Expand Up @@ -5895,7 +5920,7 @@ where
// of the onion.
failed_payment!(err_msg, err_code, sha256_of_onion.to_vec(), None);
},
Err(onion_utils::OnionDecodeErr::Relay { err_msg, err_code, shared_secret }) => {
Err(onion_utils::OnionDecodeErr::Relay { err_msg, err_code, shared_secret, .. }) => {
let phantom_shared_secret = shared_secret.secret_bytes();
failed_payment!(err_msg, err_code, Vec::new(), Some(phantom_shared_secret));
},
Expand Down
Loading

0 comments on commit 392bc6d

Please sign in to comment.