htlcswitch: add inbound routing fees receive support #6703

joostjager · 2022-07-05T13:08:27Z

This PR implements "receive" support for inbound fees. In short this means that a routing node operator gets to set distinct fee schedules for the movement of funds on their incoming channels. This enables more fine-grained flow control, potentially leading to an increase in capital efficiency.

More discussion on this change can be found in the corresponding bolts issue lightning/bolts#835 and blip lightning/blips#18

Mailing list post that elaborates a bit on the upgrade scenario and how this can be a non-breaking change: https://lists.linuxfoundation.org/pipermail/lightning-dev/2022-July/003643.html

Note that no network-wide upgrade is required for the inbound fee schedule to propagate.

Changes:

Ability to set an inbound base and proportional fee as part of the channel policy.
Broadcasting of the inbound fee schedule to the wider network.
Update the forwarding logic to take into account inbound fees. This does not break older senders as long as the inbound fee is negative.

For send support, see #6934.

Implementation details

The channel_update extra opaque data is stored in the database without any validation. This means that readers of this data must handle the case where a tlv error is encountered during parsing of the stream.

An alternative would be to do strict validation in ExtraOpaqueData.Decode when a message is received, but is more involved. It for example breaks the exisitng fuzz tests. Also, there may already be malformed tlv data in the database.
When a fee_insufficient failure happens on an intermediate node, still only the outgoing channel update is returned. The 256-byte failure message isn't able to accommodate both the incoming and outgoing channel policies until htlcswitch: relax failure message length check #6913 is widely deployed. For now, this means that senders can only receive updates to the inbound policy via gossip.

For code that shows a future extended fee_insufficient, see htlcswitch: return inbound channel update #6967.
Forwards will be declined if the total of inbound and outbound fee is negative. Negative inbound fees can be set, but it must be made sure that it is sufficiently offset by a positive outbound fee.
Inbound fees can be set on private channels, but note must be taken that those fees cannot be communicated in bolt11 hop hints. For a hinted route that spans more than a single hop and where any hop except for the final hop has an inbound fee set, the inbound fee will be ignored by the sender. For a negative inbound fee this means the sender will miss out on the discount. For a positive inbound fee, the payment will fail.

Fixes #4225

joostjager · 2022-08-22T13:39:04Z

Added a scenario that underlines the advantage of inbound fees on the spec pr: lightning/bolts#835 (comment)

Lightning Labs, what is your view on this feature?

joostjager · 2022-08-29T15:09:18Z

Created BLIP for the gossip change: lightning/blips#18

joostjager · 2022-09-04T07:36:04Z

For the fee_insufficient failure message, I think we'd want to return not just the outgoing channel update, but also the incoming channel update. That way the sender has up to date fees for the pair of channels and the next attempt should work.

The problem though is the size limit of 256 bytes on the failure message. A fee_insufficient message with two channel updates attached is 274+ bytes.

Maybe a probabilistic fix is to randomly return either the incoming or the outgoing channel update? And perhaps there is an upside to disincentivizing high frequency channel updates too. See also #6883.

bitromortac

LGTM 👍 I've manually tested gossip and sending with positive/negative inbound fees as well.

channeldb/models/inbound_fee_test.go

joostjager · 2023-12-11T09:02:33Z

Rebased

coderabbitai · 2024-01-24T09:50:35Z

Important

Auto Review Skipped

Auto reviews are limited to the following labels: llm-review. Please add one of these labels to enable auto reviews.

Please check the settings in the CodeRabbit UI or the .coderabbit.yaml file in this repository.

To trigger a single review, invoke the @coderabbitai review command.

Thank you for using CodeRabbit. We offer it for free to the OSS community and would appreciate your support in helping us grow. If you find it useful, would you consider giving us a shout-out on your favorite social media?

Share

Tips

Chat

There are 3 ways to chat with CodeRabbit:

Review comments: Directly reply to a review comment made by CodeRabbit. Example:
- I pushed a fix in commit <commit_id>.
- Generate unit testing code for this file.
- Open a follow-up GitHub issue for this discussion.
Files and specific lines of code (under the "Files changed" tab): Tag @coderabbitai in a new review comment at the desired location with your query. Examples:
- @coderabbitai generate unit testing code for this file.
- @coderabbitai modularize this function.
PR comments: Tag @coderabbitai in a new PR comment to ask questions about the PR branch. For the best results, please provide a very specific query, as very limited context is provided in this mode. Examples:
- @coderabbitai generate interesting stats about this repository and render them as a table.
- @coderabbitai show all the console.log statements in this repository.
- @coderabbitai read src/utils.ts and generate unit testing code.
- @coderabbitai read the files in the src/scheduler package and generate a class diagram using mermaid and a README in the markdown format.

Note: Be mindful of the bot's finite context window. It's strongly recommended to break down tasks such as reading entire modules into smaller chunks. For a focused discussion, use review comments to chat about specific files and their changes, instead of using the PR comments.

CodeRabbit Commands (invoked as PR comments)

@coderabbitai pause to pause the reviews on a PR.
@coderabbitai resume to resume the paused reviews.
@coderabbitai review to trigger a review. This is useful when automatic reviews are disabled for the repository.
@coderabbitai resolve resolve all the CodeRabbit review comments.
@coderabbitai help to get help.

Additionally, you can add @coderabbitai ignore anywhere in the PR description to prevent this PR from being reviewed.

CodeRabbit Configration File (`.coderabbit.yaml`)

You can programmatically configure CodeRabbit by adding a .coderabbit.yaml file to the root of your repository.
The JSON schema for the configuration file is available here.
If your editor has YAML language server enabled, you can add the path at the top of this file to enable auto-completion and validation: # yaml-language-server: $schema=https://coderabbit.ai/integrations/coderabbit-overrides.v2.json

CodeRabbit Discord Community

Join our Discord Community to get help, request features, and share feedback.

joostjager · 2024-01-24T09:50:36Z

Rebased

joostjager · 2024-01-30T15:17:24Z

Rebased

Roasbeef

LGTM ☀️

Roasbeef · 2024-03-29T23:17:33Z

lnwire/typed_fee.go

+)
+
+// Fee represents a fee schedule.
+type Fee struct {


Non-blocking given the age/lineage of this PR, but I think we should go ahead and add it to the existing ChannelUpdate struct using the new optional TLV records.

Will make a follow up issue to track this.

Sounds good

ziggie1984

LGTM 🚀

In this commit, the tlv extension of a channel update message is parsed. If an inbound fee schedule is encountered, it is reported in the graph rpc calls.

Ensure that negative fees are backwards compatible.

joostjager changed the title ~~htlcswitch: add inbound fees~~ htlcswitch: add inbound routing fees Jul 5, 2022

joostjager requested a review from Roasbeef August 22, 2022 13:41

joostjager mentioned this pull request Aug 22, 2022

Ability to set inbound and outbound fees lightning/bolts#835

Open

Roasbeef mentioned this pull request Aug 25, 2022

Ability to set inbound and outbound fees #4225

Closed

joostjager mentioned this pull request Aug 29, 2022

Inbound routing fees lightning/blips#18

Open

joostjager mentioned this pull request Sep 1, 2022

htlcswitch: add p2p inbound fee #6878

Closed

3 tasks

joostjager force-pushed the inbound-fees branch 9 times, most recently from 6a14f1e to 776391b Compare September 4, 2022 07:31

joostjager force-pushed the inbound-fees branch 12 times, most recently from de3de69 to e0d6f3f Compare September 7, 2022 06:50

joostjager requested a review from bitromortac November 14, 2023 08:45

joostjager force-pushed the inbound-fees branch from 7adc745 to 31769d8 Compare November 14, 2023 08:45

bitromortac approved these changes Dec 6, 2023

View reviewed changes

channeldb/models/inbound_fee_test.go Outdated Show resolved Hide resolved

joostjager force-pushed the inbound-fees branch from 31769d8 to a9f1b24 Compare December 11, 2023 08:58

joostjager force-pushed the inbound-fees branch from a9f1b24 to 9af961c Compare December 11, 2023 18:18

Crypt-iQ approved these changes Jan 9, 2024

View reviewed changes

joostjager force-pushed the inbound-fees branch from 9af961c to 3c52653 Compare January 24, 2024 09:50

joostjager force-pushed the inbound-fees branch 2 times, most recently from af237f8 to 3888b93 Compare January 30, 2024 15:16

Roasbeef approved these changes Mar 29, 2024

View reviewed changes

Roasbeef enabled auto-merge March 30, 2024 00:05

This was referenced Mar 30, 2024

lnwire: add InboundFee struct in-line within ChannelUpdate #8604

Open

lnwire: hard reject positive inbound fees set over RPC #8605

Open

ziggie1984 approved these changes Mar 30, 2024

View reviewed changes

ziggie1984 mentioned this pull request Mar 31, 2024

Support Inbound Fees when LND 18 is released. rkfg/regolancer#63

Open

lnwire+channeldb: parse inbound fees

3e6adbf

In this commit, the tlv extension of a channel update message is parsed. If an inbound fee schedule is encountered, it is reported in the graph rpc calls.

joostjager force-pushed the inbound-fees branch 2 times, most recently from 5348160 to 9f80df8 Compare March 31, 2024 14:42

joostjager added 3 commits March 31, 2024 16:49

htlcswitch: add receiver-side inbound fee support

e8c97de

routing+lnrpc: add inbound fee policy update

763787e

itest: multi-hop payment test with negative inbound fee

ba21ca7

Ensure that negative fees are backwards compatible.

joostjager force-pushed the inbound-fees branch from 9f80df8 to ba21ca7 Compare March 31, 2024 14:49

Roasbeef merged commit a6d4bb5 into lightningnetwork:master Mar 31, 2024
25 of 27 checks passed

feelancer21 mentioned this pull request Apr 2, 2024

Support for negative inbound fees after release of lnd 0.18 accumulator/charge-lnd#107

Closed

AndySchroder mentioned this pull request Apr 10, 2024

[feature]: allow setting to_self_delay with OpenChannel #8635

Open

softsimon mentioned this pull request May 2, 2024

Inbound routing fees receive support mempool/mempool#5031

Open

Provide feedback

Saved searches

Use saved searches to filter your results more quickly

htlcswitch: add inbound routing fees receive support #6703

htlcswitch: add inbound routing fees receive support #6703

joostjager commented Jul 5, 2022 •

edited

joostjager commented Aug 22, 2022

joostjager commented Aug 29, 2022

joostjager commented Sep 4, 2022 •

edited

bitromortac left a comment

joostjager commented Dec 11, 2023

coderabbitai bot commented Jan 24, 2024 •

edited

Auto Review Skipped

Chat

CodeRabbit Commands (invoked as PR comments)

CodeRabbit Configration File (`.coderabbit.yaml`)

CodeRabbit Discord Community

joostjager commented Jan 24, 2024

joostjager commented Jan 30, 2024

Roasbeef left a comment

Roasbeef Mar 29, 2024

Roasbeef Mar 29, 2024

joostjager Mar 31, 2024

ziggie1984 left a comment

htlcswitch: add inbound routing fees receive support #6703

htlcswitch: add inbound routing fees receive support #6703

Conversation

joostjager commented Jul 5, 2022 • edited

Implementation details

joostjager commented Aug 22, 2022

joostjager commented Aug 29, 2022

joostjager commented Sep 4, 2022 • edited

bitromortac left a comment

Choose a reason for hiding this comment

joostjager commented Dec 11, 2023

coderabbitai bot commented Jan 24, 2024 • edited

Auto Review Skipped

Chat

CodeRabbit Commands (invoked as PR comments)

CodeRabbit Configration File (.coderabbit.yaml)

CodeRabbit Discord Community

joostjager commented Jan 24, 2024

joostjager commented Jan 30, 2024

Roasbeef left a comment

Choose a reason for hiding this comment

Roasbeef Mar 29, 2024

Choose a reason for hiding this comment

Roasbeef Mar 29, 2024

Choose a reason for hiding this comment

joostjager Mar 31, 2024

Choose a reason for hiding this comment

ziggie1984 left a comment

Choose a reason for hiding this comment

joostjager commented Jul 5, 2022 •

edited

joostjager commented Sep 4, 2022 •

edited

coderabbitai bot commented Jan 24, 2024 •

edited

CodeRabbit Configration File (`.coderabbit.yaml`)