Commit Graph

231 Commits

Author SHA1 Message Date
Wilmer Paulino
8198466972
multi: move block epochs dependency from links to switch
In this commit, we move the block height dependency from the links in
the switch to the switch itself. This is possible due to a recent change
on the links no longer depending on the block height to update their
commitment fees.

We'll now only have the switch be alerted of new blocks coming in and
links will retrieve the height from it atomically.
2018-06-13 17:41:21 -07:00
Wilmer Paulino
4cc60493d2
peer+htlcswitch: randomize link commitment fee updates
In this commit, we modify the behavior of links updating their
commitment fees. Rather than attempting to update the commitment fee for
each link every time a new block comes in, we'll use a timer with a
random interval between 10 and 60 minutes for each link to determine
when to update their corresponding commitment fee. This prevents us from
oscillating the fee rate for our various commitment transactions.
2018-06-13 17:41:01 -07:00
Conner Fromknecht
4380c67124
htlcswitch/link: upgrade to use lnpeer.Peer.SendMessage 2018-06-08 16:29:49 -07:00
Olaoluwa Osuntokun
4bde4c1c26
Merge pull request #1333 from Roasbeef/min-fee-rate
funding+htlcswitch: enforce min fee rate of 253 sat/kw on commitments
2018-06-06 21:00:13 -07:00
Conner Fromknecht
c180065a84
htlcswitch/link: remove deadlock in htlc validation
This commit removes a possible deadlock in the switch,
which can be triggered under certain failure conditions.
Previously, we would acquire the link's read lock for
the duration of HtlcSatisfiesPolicy, though we only
need to use it grab the current policy. The deadlock could
be caused in the cases where we attempt to log the failure,
which access the read-protected ShortChanID method.
2018-06-06 18:11:36 -07:00
Olaoluwa Osuntokun
8f68d0e605
funding+htlcswitch: enforce min fee rate of 253 sat/kw on commitments
In this commit, we add and enforce a min fee rate for commitment
transactions created, and also any updates we propose to the remote
party. It's important to note that this is only a temporary patch, as
nodes can dynamically raise their min fee rate whenever their mempool is
saturated.

Fixes #1330.
2018-06-05 17:50:50 -07:00
Johan T. Halseth
f95ae1cdd6
htlcswitch/link: add failed variable to ensure exit 2018-05-25 06:58:24 +02:00
Johan T. Halseth
49fd3f34d4
htlcswitch/link: settle with fake preimage if BogusSettle active 2018-05-25 06:58:24 +02:00
Johan T. Halseth
fbec83699c
htlcswitch/link: make fail() call OnChannelFailure with LinkFailureError
Adds a new closure OnChannelFailure to the link config, which is called
when the link fails. This function closure should use the given
LinkFailureError to properly force close the channel, send an error to
the peer, and disconnect the peer.
2018-05-25 06:58:23 +02:00
Conner Fromknecht
3e46a5e815
htlcswitch/link: fix UpdateShortChanID 2018-05-09 16:07:25 -07:00
Olaoluwa Osuntokun
ddcbb40898
Merge pull request #1206 from wpaulino/temp-chan-failure-update
htlcswitch+server: ensure we always send an update w/ a TempChannelFailure
2018-05-08 19:33:20 -07:00
Conner Fromknecht
de9de771bb
htlcswitch/link: ensure circuits are committed in-order
This commit makes the call to forwardBatch after locking
in Adds synchronous. This ensures that circuits for any Add
packets are added to the switch in the same order that they
are prescribed in the channel state. Though it is very unlikely
this case would arise, it may happen under more greater loads.

In addition, this also makes some trivial optimizations wrt. to
not spawning unnecessary goroutines if no settle/fail packets
are locked in.
2018-05-08 16:37:35 -07:00
Olaoluwa Osuntokun
72f48b6abe
htlcswitch+server: ensure we always send an update w/ a TempChannelFailure
In this commit, we ensure that any time we send a TempChannelFailure
that's destined for a multi-hop source sender, then we'll always package
the latest channel update along with it.
2018-05-08 13:00:28 -04:00
littleskunk
d2a6c4eec9 htlcswitch: typo fix 2018-05-07 21:33:32 -07:00
Olaoluwa Osuntokun
ddd12eff9c
htlcswitch: move link trimming to link start up
In this commit, we fix a race in the set of TestChannelLinkTrimCircuits*
tests. Before this commit, we would trim the circuits in the htlcManager
goroutine. However, this was problematic as the scheduling order of
goroutines isn't predictable. Instead, we'll now trim the circuits in
the Start method.

Additionally, we fix a series of off-by-2 bugs in the tests themselves.
2018-05-03 20:11:52 -07:00
Conner Fromknecht
42a9a78180
htlcswitch/link: trim fix 2018-05-02 01:12:18 -07:00
Conner Fromknecht
a36e1e6278
htlcswitch/link: adds HodlFlag breakpoints
This commit inserts an initial set of HodlFlags into
their correct places within the switch. In lieu of the
existing HtlcHodl mode, it is been replaced with a
configurable HodlMask, which is a bitvector representing
the desired breakpoints. This will allow for fine grained
testing of the switch's internals, since we can create
arbitrary delays inside a otherwise asynchronous system.
2018-05-02 00:18:51 -07:00
Johan T. Halseth
bc6b8a7eeb
htlcswitch/link: rename UnilateralClose -> RemoteUnilateralClose 2018-04-25 09:37:22 +02:00
Dimitris Tsapakidis
4009f7f874 multi: fix typos in comments 2018-04-17 19:03:27 -07:00
Olaoluwa Osuntokun
7037d55f65
htlcswitch: perform fee related checks at forwarding time
In this commit, we fix a very old, lingering bug within the link. When
accepting an HTLC we are meant to validate the fee against the
constraints of the *outgoing* link. This is due to the fact that we're
offering a payment transit service on our outgoing link. Before this
commit, we would use the policies of the *incoming* link. This would at
times lead to odd routing errors as we would go to route, get an error
update and then route again, repeating the process.

With this commit, we'll properly use the incoming link for timelock
related constraints, and the outgoing link for fee related constraints.
We do this by introducing a new HtlcSatisfiesPolicy method in the link.
This method should return a non-nil error if the link can carry the HTLC
as it satisfies its current forwarding policy. We'll use this method now
at *forwarding* time to ensure that we only forward to links that
actually accept the policy. This fixes a number of bugs that existed
before that could result in a link accepting an HTLC that actually
violated its policy. In the case that the policy is violated for *all*
links, we take care to return the error returned by the *target* link so
the caller can update their sending accordingly.

In this commit, we also remove the prior linkControl channel in the
channelLink. Instead, of sending a message to update the internal link
policy, we'll use a mutex in place. This simplifies the code, and also
adds some necessary refactoring in anticipation of the next follow up
commit.
2018-04-06 14:52:00 -07:00
Olaoluwa Osuntokun
b3bc374ba1
htlcswitch: send a direct Error if we get a known channel error on validate commit 2018-04-04 17:41:47 -07:00
Olaoluwa Osuntokun
0dbd325fd0
htlcswitch: synchronously send the error to the peer on commitment verify fail
In this commit, we fix a slight bug in lnd. Before this commit, we would
send the error to the remote peer, but in an async manner. As a result,
it was possible for the connections to be closed _before_ the error
actually reached the remote party. The fix is simple: wait for the error
to be returned when sending the message. This ensures that the error
reaches the remote party before we kill the connection.
2018-04-04 17:38:35 -07:00
Olaoluwa Osuntokun
5984cbd4ff
htlcswitch: allow overpaying for incoming payments
In this commit, we relax the constraints on accepting an exit hop
payment a bit. We'll now accept any incoming payment that _at least_
pays the invoice amount. This puts us further inline with the
specification, which recommends that nodes accept overpayment by a
certain margin.

Fixes #1002.
2018-04-02 15:58:56 -07:00
Conner Fromknecht
d13a566284
htlcswitch/link: DecodeOnionObfuscator -> ExtractErrorEncrypter 2018-03-13 16:33:28 -07:00
Olaoluwa Osuntokun
8988a07bce
htlcswitch: eliminate unnecessary indentation in processRemoteAdds
In this commit, we remove a ton of unnecessary indentation in the
processRemoteAdds method. Before this commit, we had a switch statement
on the type of the entry. This was required before when the method was
generic, but now since we already know that it’s an Add, we no longer
require such a statement.
2018-03-12 18:58:46 -07:00
Olaoluwa Osuntokun
069311c47f
htlcswitch: log dangling circuits in unable to create new commitment 2018-03-12 18:58:45 -07:00
Olaoluwa Osuntokun
bdd01cccb2
htlcswitch: remove getBandwidthCmd as it's no longer needed 2018-03-12 18:58:45 -07:00
Olaoluwa Osuntokun
1af8fa9367
htlcswitch: add additional comments and logging 2018-03-12 18:58:44 -07:00
Olaoluwa Osuntokun
c285bb5814 htlcswitch+peer: remove DecodeHopIterator from ChannelLinkConfig
In this commit, we remove the DecodeHopIterator method from the
ChannelLinkConfig struct. We do this as we no longer use this method,
since we only ever use the DecodeHopIterators method now.
2018-03-12 18:58:08 -07:00
Johan T. Halseth
33762e0f81
htlcswitch/link: fail channel on lnwire.Error 2018-03-11 17:21:23 +01:00
Conner Fromknecht
101ad09e9f
htlcswitch/link: batches processing of locked in htlcs 2018-03-09 21:08:43 -08:00
Conner Fromknecht
1fe7c6d431
htlcswitch/link: integrate persistence changes to lnwallet APIs 2018-03-09 17:35:53 -08:00
Olaoluwa Osuntokun
649be5ee0b
Merge pull request #775 from cfromknecht/sphinx-replay
Switch Persistence [1/4]: Infra for Sphinx Batched Decoding and Replay Protection
2018-03-08 23:03:01 -05:00
Conner Fromknecht
27df8d8ad1
htlcswitch/link: extract error encrypter from hop iterator 2018-03-08 21:12:04 -05:00
Olaoluwa Osuntokun
7031b5d217
htlcswitch: modify forwarding fee assertion to compare emperical fees
In this commit, we fix a bug that was uncovered by the recent change to
lnwire.MilliSatoshi. Rather than manually compute the diff in fees,
we’ll directly compare the fee that is given against the fee that we
expect.
2018-03-08 12:50:49 -05:00
Olaoluwa Osuntokun
473dfd115b
htlcswitch: add set of tests for the forwarding log 2018-03-06 13:56:11 -05:00
Olaoluwa Osuntokun
6f11fee1a4
htlcswitch: when forwarding htlcs, set the incomingHtlcAmt 2018-03-06 13:56:10 -05:00
Olaoluwa Osuntokun
d377ffafdd
htlcswitch: populate the incoming+outgoing in the payment circuit 2018-03-06 13:56:10 -05:00
Johan T. Halseth
80277c0517
htlcswitch: use fee rate types instead of btcutil.Amount for fee rates 2018-02-26 22:42:25 +01:00
Johan T. Halseth
e6f7a46d90
htlcswitch: don't return negative value from Bandwidth()
This commits prevents the Bandwith() method from returning
a negative value if the channel reserve is larger than
the actual available balance.
2018-02-08 18:35:24 -05:00
nsa
7e84892c21
htlcswitch: account for channel reserve in Bandwidth 2018-02-08 18:35:23 -05:00
practicalswift
a93736d21e multi: comprehensive typo fixes across all packages 2018-02-06 19:11:11 -08:00
Olaoluwa Osuntokun
18741831dd
Merge pull request #485 from halseth/fix-negative-balance
Use remoteACKed index when calculating availableBalance.
2018-02-05 16:23:17 -08:00
Olaoluwa Osuntokun
30dbbd69a0
funding+htlcswitch: dynamically update short chan id of existing link
In this commit, we fix an existing bug that would result in some
payments getting “stuck”. This would happen if one side restarted
before the channel was fully locked in. In this case, since upon
re-connection, the link will get added to the switch with a *short
channel ID of zero*. If A then tries to make a multi-hop payment
through B, B will fail to forward the payment, as it’ll mistakenly
think that the payment originated from a local-subsystem as the channel
ID is zero. A short channel ID of zero is used to map local payments
back to their caller.

With fix this by allowing the funding manager to dynamically update the
short channel ID of a link after it discovers the short channel ID.

In this commit, we fix a second instance of reported “stuck” payments
by users.
2018-02-03 18:14:15 -08:00
Johan T. Halseth
9b7b3fa3b6
channellink: make BatchTicker and BatchSize configurable
This commit introduces a new Ticker interface, that can be used
to control when the batch timer should tick. This is done to be
able to more easily control the ticker during tests. The batch
timer is wrapped in the new BatchTicker struct, and made part
of the config together with BatchSize.
2018-02-02 21:16:36 -05:00
Wilmer Paulino
f0d6d31ca4
htlcswitch: allow sending htlcs when paying invoices with a zero amount 2018-01-27 19:05:23 -05:00
Olaoluwa Osuntokun
f8adab1f1c
test: add comprehensive integration tests for on-chain HTLC handling
In this commit, we add 6 new integration tests to test the various
actions that may need to be performed when either side goes on-chain to
fully resolve HTLC’s. Many of the tests are mirrors of each other as
they test sweeping/resolving HTLC’s from both commitment transactions.
2018-01-22 19:20:02 -08:00
Olaoluwa Osuntokun
96fbc7da84
htlcswitch: fix deadlock during chainWatcher notifications 2018-01-22 19:19:59 -08:00
Olaoluwa Osuntokun
239416f242
htlcswitch: update to use new event stream from the chainWatcher 2018-01-22 19:19:51 -08:00
Olaoluwa Osuntokun
703057c821
htlcswitch: with debughtlc+hodlhtlc mode, skip all HTLC level checks 2018-01-22 19:19:41 -08:00
Olaoluwa Osuntokun
dbe76a1507
htlcswitch: upon restart, examine all active HTLC's, settle those that we can
In this commit, we address a lingering TODO: before this if we had a
set of HTLC’s that we knew the pre-image to on our commitment
transaction after a restart, then we wouldn’t attempt to settle them.
With this new change, we’ll check that we didn’t already retransmit the
settles for them, and check the preimage cache to see if we already
know the preimage. If we do, then we’ll immediately settle them.
2018-01-22 19:19:40 -08:00
Olaoluwa Osuntokun
ca4eb970ec
htlcswitch: move channel re-sync into distinct function 2018-01-22 19:19:40 -08:00
Olaoluwa Osuntokun
2d133acaeb
htlcswitch: after each new state update, notify callers to set of new HTLC's 2018-01-22 19:19:39 -08:00
Olaoluwa Osuntokun
1418d672f9
htlcswitch: notify the ChainArbitrator of fresh signals upon link creation 2018-01-22 19:19:39 -08:00
Olaoluwa Osuntokun
f2642a70db
htlcswitch: once we discover a pre-image, add it to the witness cache
In this commit, we add some additional logic to the case when we
receive a pre-image from an upstream peer. We’ll immediately add it to
the witness cache, as an incoming HTLC might be waiting on-chain to
fully resolve the HTLC with knowledge of the newly discovered
pre-image.
2018-01-22 19:19:39 -08:00
Johan T. Halseth
9bdb483757
htlcswitch/link: make MinHTLC non-changable
This commit specifies that the MinHTLC value for a link is static
over the lifetime of a channel, and don't process the field
during a policyUpdate.
2018-01-12 22:56:29 +01:00
Olaoluwa Osuntokun
912366ada5
htlcswitch: fix notifier goroutine leak by cancelling epoch when htlcManager exits
Before this commit, if the htlcManager unexpectedly exited (due to a
protocol error, etc), the underlying block epoch notification intent
that was created for it would never be cancelled. This would result in
tens, or hundreds of goroutine leaks as the client would never consume
those notifications.

To fix this, we move cancellation of the block epoch intent from the
Stop() method of the channel link, to the defer statement at the top of
the htlcManager.
2018-01-08 19:50:24 -08:00
Olaoluwa Osuntokun
dbf6a511fc
htlcswitch: if we detect an InvalidCommitSigError, send over detailed error
In this commit, we add an additional case when handling a failed
commitment signature. If we detect that it’s a InvalidCommitSigError,
then we’ll send over an lnwire.Error message with the full details. We
don’t yet properly dispatch this error on the reciting side, but that
will be done in a follow up a commit.
2018-01-08 19:50:23 -08:00
Olaoluwa Osuntokun
e2fe4c2955
htlcswitch: reject duplicate payments to same invoice
In this commit, we modify the way the link handles HTLC’s that it
detects is destined for itself. Before this commit if a payment hash
came across for an invoice we’d already settled, then we’d gladly
accept the payment _again_. As we’d like to enforce the norm that an
invoice is NEVER to be used twice, this commit modifies that behavior
to instead reject an incoming payment that attempts to re-use an
invoice.

Fixes #560.
2018-01-04 14:23:37 -06:00
Jim Posen
88dc73adb0 htlcswitch: Fix failure error handling on outgoing adds. 2017-12-14 17:53:58 -08:00
Jim Posen
6ea533275c htlcswitch: Remove obsolete fields from htlcPacket. 2017-12-14 17:53:58 -08:00
Jim Posen
40fb0ddcfc htlcswitch: Assign each pending payment a unique ID.
This simplifies the pending payment handling code because it allows it
be handled in nearly the same way as forwarded HTLCs by treating an
empty channel ID as local dispatch.
2017-12-14 17:53:58 -08:00
Jim Posen
4a29fbdab2 htlcswitch: Rename htlcPacket fields for clarity.
The src/dest terminology for routing packets is kind of confusing
because the source HTLC may not be the source of the packet for
settles/fails traversing the circuit in the opposite direction. This
changes the nomenclature to incoming/outgoing and always references
the HTLCs themselves.
2017-12-14 17:53:58 -08:00
Jim Posen
317b44e220 lnwallet: Change channel update methods to accept HTLC ID.
Previously, some methods on a LightningChannel like SettleHTLC and
FailHTLC would identify HTLCs by payment hash. This would not always
work correctly if there are multiple HTLCs with the same payment hash,
so instead we change these methods to identify HTLCs by their unique
identifiers instead.
2017-12-14 17:53:58 -08:00
Jim Posen
1328e61c00 htlcswitch: Change circuit map keys to (channel ID, HTLC ID).
This changes the circuit map internals and API to reference circuits
by a primary key of (channel ID, HTLC ID) instead of paymnet
hash. This is because each circuit has a unique offered HTLC, but
there may be multiple circuits for a payment hash with different
source or destination channels.
2017-12-14 17:53:58 -08:00
Jim Posen
bc8d674958 htlcswitch: Remove constructor functions for htlcPacket.
The constructor functions have no additional logic other than passing
function parameters into struct fields. Given the large function
signatures, it is more clear to directly construct the htlcPacket in
client code than call a function with lots of positional arguments.
2017-12-14 17:53:58 -08:00
Olaoluwa Osuntokun
4cca23264d
htlcswitch: add new default case when handling UpdateFailMalformedHLTC
In this commit, we modify the existing logic to handle
UpdateFailMalformedHLTC message from an incoming peer. Rather than fail
the Chanel if they give us an invalid failure code, we’ll instead treat
it as a temporary channel failure so we can continue to forward the
error.
2017-12-12 11:42:47 -08:00
Olaoluwa Osuntokun
c3d345b575
htlcswitch: don't add UpdateFee to channel if not able to forward
This commit is a follow up to a prior commit which skipped sending the
commitment sig message (and sending out the update fee) message if the
channel wasn’t yet able to forward any HTLC’s. We’ll modify the prior
commit to not add the fee update to the channel at all. Otherwise, we
risk a state desynchronization.
2017-12-10 16:19:21 -08:00
Ben Congdon
720a8c7e96 htlcswitch: Only send UpdateFee message when channel is eligible
This commit adds a check to `updateChannelFee` which skipssending the
`update_fee` message when the channel is not eligable for forwarding
messages (likely due to the channel's `RemoteNextRevocation` not yet
being set).

This addresses #470.
2017-12-10 10:46:30 -08:00
Olaoluwa Osuntokun
669c2ee1a0
htlcswitch: only re-send FundingLocked if the channel is fully confirmed 2017-12-06 16:43:02 -08:00
Olaoluwa Osuntokun
36956d390f
htlcswitch: add new method to the ChannelLink interface, EligibleToForward
In this commit, we add a new method to the ChanneLink interface:
EligibleToForward. This method allows a link to be added to the switch,
but in an intermediate state which indicates that it isn’t yet ready to
forward any incoming HTLC’s.
2017-12-06 16:42:57 -08:00
Olaoluwa Osuntokun
260ff8831a
htlcswitch: update UpdateFee usage due to recent API change 2017-11-30 22:17:56 -08:00
Olaoluwa Osuntokun
62473009b5
htlcswitch: within link, with each new block, check to see if commit fee should change
In this commit we add a new case to the main select statement within a
channel link. This select statement will serve as a Sipping Bird which
will check the network fee rate (as returned by the fee estimator) and
compare that to the fee on the commitment transaction. Using the
shouldAdjustCommitFee function, we determine if we should update the
commitment fee. If so, then we’ll send an UpdateFee message and also
trigger a new commitment update.

We also add a new unit test: TestChannelLinkUpdateCommitFee to ensure
that we update the fee accordingly if the fee increases or decreases by
a large portion.
2017-11-23 23:10:19 -06:00
Olaoluwa Osuntokun
c560200ba1
htlcswitch: add new shouldAdjustCommitFee helper function
In this commit, we add a new helper function to the link which will be
utilized in a later commit. This helper function will help us determine
if we should update the commitment fee, in response to a change in the
network fee return by our fee estimators.
2017-11-23 23:10:19 -06:00
Olaoluwa Osuntokun
25082f0b5b
htlcswitch: update WipeChannel on Peer interface to simply take the chanPoint
The WipeChannel method doesn’t need to take the channel itself, as any
relevant indexes should be able to be queried based on the channel
point along.
2017-11-23 23:10:10 -06:00
Olaoluwa Osuntokun
6afebfba5d
htlcswitch: update link to match latest ChanSyncMsg API change 2017-11-16 20:00:06 -08:00
Olaoluwa Osuntokun
632f230fef
htlcswitch: add quit case to initial channel state sync select in channelLink
In this commit we add a quit case to the select statement that’s
entered once a link is created. Before this commit, upon restart it
would be possible that the deamon would never ben able to shutdown as
the link would be waiting for the messages to be sent by the other
side.
2017-11-10 19:51:13 -08:00
Olaoluwa Osuntokun
a48ceac98f
htlcswitch: update link to adhere to new channeldb API's 2017-11-10 19:51:03 -08:00
Olaoluwa Osuntokun
ea334e4d47
htlcswitch: re-write channel connection re-establishment for correctness
In this commit, we’ve re-written the process of syncing the state of
channels after we reconnect. This re-write ensure correctness, and also
simplified the existing logic which would attempt to launch another
goroutine to handle requests from the switch to ensure that it doesn’t
block. This is no longer necessary as the AddPacket method that the
switch indirectly calls is non-blocking.
2017-11-10 19:51:03 -08:00
Olaoluwa Osuntokun
de3af9b0c0
htlcswitch: modify Bandwidth() method on links to use more accurate accoutning
In this commit, we modify the existing implementation of the
Bandwidth() method on the default ChannelLink implementation to use
much tighter accounting. Before this commit, there was a bug wherein if
the link restarted with pending un-settled HTLC’s, and one of them was
settled, then the bandwidth wouldn’t properly be updated to reflect
this fact.

To fix this, we’ve done away with the manual accounting and instead
grab the current balances from two sources: the set of active HTLC’s
within the overflow queue, and the report from the link itself which
includes the pending HTLC’s and factors in the amount we’d need to (or
not need to) pay in fees for each HTLC.
2017-11-10 19:51:02 -08:00
Olaoluwa Osuntokun
70ed50738a
htlcswitch: utilize memoryMailBox within link, no longer spawn goroutine to forward in switch
In this commit, we’ve modified the link and the switch to start to use
the new mailBox in place of the existing synchronous message send
directly into the link’s upstream/downstream channels. With his change,
we no longer need to spawn a new goroutine each time an HTLC needs to
be forwarded, or a user payment is initiated.
2017-11-10 19:51:02 -08:00
Andrey Samokhvalov
9247168c5d not finished index persistence 2017-11-09 16:38:58 -08:00
Andrey Samokhvalov
a10ed36e8f htlcswitch+lnwallet: add malformed payment descriptor 2017-11-09 16:38:58 -08:00
Andrey Samokhvalov
e29193d550 htlcswitch+channel: remove cancel reasons from channel link 2017-11-09 16:38:58 -08:00
Andrey Samokhvalov
1b4e723a5d htlcswicth+channel: switch to store onion blobs in payment descriptor
After addition of the retransmission logic in the channel link, we
should make the onion blobs persistant, the proper way to do this is
include the onion blobs in the payment descriptor rather than storing
them in the distinct struct in the channel link.
2017-11-09 16:38:57 -08:00
Andrey Samokhvalov
d70ffe93e4 htlcswitch+channel: add channel states synchronization
In this commit BOLT№2 retranmission logic for the channel link have
been added. Now if channel link have been initialised with the
'SyncState' field than it will send the lnwire.ChannelReestablish
message and will be waiting for receiving the same message from remote
side. Exchange of this message allow both sides understand which
updates they should exchange with each other in order sync their
states.
2017-11-09 16:38:57 -08:00
Andrey Samokhvalov
bea9c0b52b htlcswitch: make stop of the link not in the goroutine
In order to be able to properly restart switch several times we should
have the sequential process of channel link stop. In other words if we
stopped the switch we should be sure that all channel links have been
stopped too. Addition of the goroutine during the force close was added
because of the deadlock:

Trace:
1. link:force_close_notification
2. link:wipe_channel
3. peer:switch_remove_link
4. switch:stop_link
5. link:wait <-- deadlock
2017-11-09 16:38:57 -08:00
Jim Posen
2b58a39d30 lnwallet: Simplify updateLog struct by removing redundant pointers.
The updateLog struct contains pointers that refer to the state of the
commitment chains. Instead, query the commitments directly.
2017-10-25 13:11:46 -07:00
Olaoluwa Osuntokun
e02af3f877
htlcswitch: as exit node check for invoice and HTLC value match after existence 2017-10-22 18:37:00 -07:00
Olaoluwa Osuntokun
74165ca8c1
htlcswitch: update l.clearedOnionBlobs in link to use new HtlcIndex 2017-10-22 18:36:57 -07:00
Olaoluwa Osuntokun
6a255fb588
htlcswitch: relax timelock verification in middle link to allow for shadow routes
In this commit, we relax the time lock verification when we realize
we’re an intermediate hop. We no longer directly assert that the time
lock we receive is _identical_, instead we allow slow slack and will
reject iff, the incoming timelock minus the outgoing time lock doesn’t
meet our delta requirements.
2017-10-22 18:36:56 -07:00
Olaoluwa Osuntokun
12ae63101d
Htlcswitch: rename Deobfuscator and Obfuscator interfaces
This commit renames the Deobfuscator interface to ErrorDecrypter and
the Obfuscator interface to ErrorEncrypter. With this rename, the
purpose of these two interfaces are a bit clearer.

Additionally, DecryptError (which was formerly Deobfuscate) now
directly returns an ForwardingError type instead of the
lnwire.FailureMessage.
2017-10-10 22:19:19 -07:00
Olaoluwa Osuntokun
ebd2dfbfd9
htlcswitch: use Tracef rather than Debugf for log examining HTLC's 2017-10-04 20:46:04 -07:00
Olaoluwa Osuntokun
710c2f5dac
htlcswitch: if unable to add half in channel link, properly increment bandwidth
This commit fixes an existing bug, wherein if we failed to account for
the fact that if we we’re unable to add an HTLC for any reason other
than an overflown commitment transaction, then we wouldn’t properly
re-add the available bandwidth of the offending HTLC.
2017-10-02 22:14:15 -07:00
Johan T. Halseth
5d03256baf
htlcswith/link: resend fundingLocked from channelLink when numUpdates == 0.
In the case where the channelLink get started and the number of
updates on this channel is zero, this means no paymenys has been
done using this channel. This might mean that the fundingLocked
never was sent successfully, so we resend to make sure this
channel gets opened correctly.
2017-10-02 13:29:50 +02:00
Olaoluwa Osuntokun
7ae436e30e
htlcswitch+test: send switch back error on lnwallet.ErrInsufficientBalance
This commit fixes a bug related to swallowing an error that should go
to the switch in the case of an insufficient balance error when
attempting to add a new HTLC to the channel state machine. In this
case, an error would never be returned back to the client/switch, and
the internal processing within the channelLink would loop forever,
attempting to add an HTLC that can’t be added due to insufficient
balance to state machine itself.

We fix this issue by only treating the lnwallet.ErrMaxHTLCNumber as the
only error that prompts adding an HTLC to the overflow queue rather
than sending the error directly back to the switch.
2017-09-25 16:10:20 -07:00
Olaoluwa Osuntokun
be5b2d46a5
htlcswitch: ensure the packetQueue can handle total+partial commitment overflows
In this commit, we’ve moved away from the internal queryHandler within
the packetQueue entirely. We now use an internal queueLen variable
internally to allow callers to sample the queue’s size, and also for
synchronization purposes internally.

This commit also introduces a chan struct{} (freeSlots) that is used
internally as a semaphore. The current value of freeSlots reflects the
number of available slots within the commitment transaction. Within the
link, after an HTLC has been removed/modified, then a “slot” is freed
up. The main packetConsumer then interprets these messages as a signal
to attempt to free up a new slot within the queue itself by dumping off
to the commitment transaction.
2017-09-25 12:47:34 -07:00
Olaoluwa Osuntokun
64317c04f1
htlcswitch: use atomic integer to track link bandwidth internally
This commit modifies the way the bandwidth of a given channel link is
tracked, and reported externally. The prior approach pushed most of the
logic for tracking channel bandwidth into the link itself, and relied
on a report from the queue in order to determine the total available
bandwidth. This approach at times could inadvertently introduce
deadlocks when working on new features as since the query was handled
internally, it required the link to be _active_ and non-blocked in
order to respond to.

We’ve now abandoned this approach in favor of lifting the bandwidth
accounting to the highest possible abstraction layer within the link
itself. We now maintain a availableBandwidth integer that’s used
atomically within the link in response to: us adding+settling an HTLC,
and the remote party failing one of our HTLC’s.
2017-09-25 12:31:59 -07:00
Olaoluwa Osuntokun
457aebd16f
htlcswitch: ensure channel state machine is stopped on link stoppage 2017-09-22 15:56:12 -07:00
Olaoluwa Osuntokun
6f5ef249e4
htlcswitch: re-write link's packet overflow queue for readability+extensibility
This commit completes a full re-write of the link’s packet overflow
queue with the goals of the making the code itself more understandable
and also allowing it to be more extensible in the future with various
algorithms for handling HTLC congestion avoidance and persistent queue
back pressure.

The new design is simpler and consumes much less coroutines (no longer
a new goroutine for each active HLTC). We now implement a simple
synchronized queue using a standard condition variable.
2017-09-22 15:54:16 -07:00
Conner Fromknecht
74322a99be config+htlclink+peer: htlc hodl mode!
This commit adds a new debug mode for lnd
  called hodlhtlc. This mode instructs a node
  to refrain from settling incoming HTLCs for
  which it is the exit node. We plan to use
  this in testing to more precisely control
  the states a node can take during
  execution.
2017-09-19 11:31:52 -07:00
Olaoluwa Osuntokun
bf071c1985
htlcswitch: properly verify OutgoingCTLV+Timeout when final hop in link
This commit fixes an existing bug in the way we perform validation of
the timelock information as the final hop in the route. Previously, we
would assert that the outgoing time lock in the per-hop payload would
exactly match our time lock delta.

Instead, we should be asserting two things:
   1. That the time lock in the payload is >= the expected time lock
   2. That timeout on the HTLC is exactly equal to the payload
2017-09-12 22:04:59 +02:00
Olaoluwa Osuntokun
475c3b6c0c
htlcswitch: accept over-paid HTLC's fee-wise
This commit modifies fee acceptance logic to allow remote nodes to
*over pay* for the HTLC’s sent.
2017-08-22 00:53:20 -07:00
Olaoluwa Osuntokun
4d92d23762
htlcswitch: add new UpdateForwardingPolicies method
This commit adds a new method to the HtlcSwitch:
UpdateForwardingPolicies. With this method callers are now able to
modify the forwarding policies of all, or some currently active links.
We also make a slight modification to the way that forwarding policy
updates are handled within the links themselves to ensure that we don’t
override with a zero value for any of the fields.
2017-08-22 00:53:18 -07:00
Olaoluwa Osuntokun
8a51b1a0c6
Htlcswitch: switch all accounting and forwarding decisions to use mSAT's 2017-08-22 00:53:04 -07:00
Olaoluwa Osuntokun
572eef2840
htlcswitch: add channel point prefix to HTLC examine logs 2017-08-15 17:55:06 -07:00
Olaoluwa Osuntokun
cdb7436e34
htlcswitch: update tests to account for new HTLC expiry observence 2017-08-02 21:11:40 -07:00
Olaoluwa Osuntokun
ee1acb1610
htlcswitch: reject HTLC's which expire too soon
This commit implements a missing policy within the current ChannelLink
interface. If an HTLC arrives that is too close to the current block
height, then we’ll reject it. As otherwise, it may be possible for us
to lose an on-chain claim if they HTLC expires already or expires
before we’re able to get a commitment transaction in the chain.

As the exit node, we have a grace period that governs out decision. As
an intermediate node, we ensure that the HTLC isn’t close to expiry on
our outgoing link end if we forward it.
2017-08-02 21:10:43 -07:00
Olaoluwa Osuntokun
8eadd09403
htlcswitch: add additional logging statement when forwarding HTLC's 2017-07-30 17:52:25 -07:00
Olaoluwa Osuntokun
2d1a598b66
htlcswitch: modify channelLink to use new create+verify commitment API 2017-07-30 17:51:16 -07:00
Olaoluwa Osuntokun
f7c4237686
htlcswitch: remove initial revocation window extension in channelLink
We can safely remove the initial revocation window extension as this
has gone away with the new state machine. We instead now just fill the
window once the channel has been opened, and then maintain a fixed
window size of 2 from there on.
2017-07-30 17:51:13 -07:00
Olaoluwa Osuntokun
a04fa76a4c
lnwire+htlcswitch: minor grammatical, formatting fixes after error PR 2017-07-14 20:08:37 -07:00
Andrey Samokhvalov
2d378b3280 htlcswitch+router: add onion error obfuscation
Within the network, it's important that when an HTLC forwarding failure
occurs, the recipient is notified in a timely manner in order to ensure
that errors are graceful and not unknown. For that reason with
accordance to BOLT №4 onion failure obfuscation have been added.
2017-07-14 19:08:04 -07:00
Andrey Samokhvalov
ef73062c14 peer+server+htlcswitch: add reason to disconnnect function
In order to recognize exact reason of the disconnect the additional
field have been added in the disconnect function.
2017-07-14 19:08:04 -07:00
Johan T. Halseth
f4db249cb8 htlcswitch: handle update_fee message received from peer.
This commit makes the channellink update a channel's fee
if an update_fee message is received from the peer.
2017-07-14 16:39:15 -07:00
Olaoluwa Osuntokun
01d54c29af
htlcswitch: restore the ability to properly handle debughtlc recv's
This commit fixes a regression introduce in the prior commit which
added full verification of the per-hop payloads to the ChannelLink
interface. When this was initially implemented, the added checks
weren’t guarded on the existence of debughtlc’s. As a result,
debughtlc’s would be rejected as they don’t match the expected invoice
value.

This commit fixes that issue by only checking the hop payload if debug
HTLC mode isn’t on.
2017-07-04 15:58:23 -07:00
Olaoluwa Osuntokun
4b0e331c62
htlcswitch: fix linter issues 2017-06-17 01:04:21 +02:00
Olaoluwa Osuntokun
399d193e2c
htlcswitch: add a new UpdateFeePolicy to ChannelLink interface
This commit adds a new method to the ChannelLink interface which is
meant to allow outside sub-system to update the forwarding policy of a
channel. This can be triggered either by a new RPC method, or
automatically by some sort of control system which seeks to optimize
fee revenue, or block off channels, etc.
2017-06-17 00:01:10 +02:00
Olaoluwa Osuntokun
cd10dc712f
htlcswitch: implement full HTLC onion payload validation logic
This commit puts a missing piece in place by properly parsing and
validating the per hop payload received in incoming HTLC’s. When
forwarding HTLC’s we ensure that the payload recovered is consistent
with our current forwarding policy. Additionally, when we’re the “exit
node” for a payment, then we ensure that the HTLC extended matches up
with our expectation w.r.t the payment amount to be received.
2017-06-16 23:58:08 +02:00
Olaoluwa Osuntokun
ea57a94c2e
htlcswitch: add a ShortChanID method to the ChannelLink interface 2017-06-16 23:32:47 +02:00
Olaoluwa Osuntokun
058e641d7e
htlcswitch: add new ForwardingPolicy struct guide forwarding decisions 2017-06-16 23:31:00 +02:00
Olaoluwa Osuntokun
2ab03c57be
htlcswitch: re-introduce dynamic commitment log tick timer
This commit fixes a slight regression in the logic of the switch by
ensuring that the log commitment timer is only start _after_ we receive
a new commitment signature. Otherwise, the ticker will keep ticking and
possibly settle HTLC’s that’ve yet to be locked in, or waste a
signature causing us to be deprived of a revocation which is required
for us to initiate a new state transition.

Additionally, the commit performs a few minor post-merge clean ups.
2017-05-31 16:43:48 -07:00
Andrey Samokhvalov
a5d90b9ad1 htlcswitch: fix last-mile settle stalling in concurrent multi-hop setting
This commit fixes an issue that would at times cause the htlcManager
which manages the link that’s the final hop to settle in an HTLC flow.
Previously, a case would arise wherein a set of HTLC’s were settled to,
but not properly committed to in the commitment transaction of the
remote node. This wasn’t an issue with HTLC’s which were added but
uncleared, as that batch was tracked independently.

In order to fix this issue, we now track pending HTLC settles
independently. This is a temporary fix, as has been noted in a TODO
within this commit.
2017-05-31 11:06:08 -07:00
Andrey Samokhvalov
7595bee27c htlcswitch: add usage of queue in channel link
In this commit usage of the pending packet queue have been added.
This queue will consume the downstream packets if state machine return
the error that we do not have enough capacity for htlc in commitment
transaction. Upon receiving settle/fail payment descriptors - add htlc
have been removed, we release the slot, and process pending add htlc
requests.
2017-05-31 11:06:08 -07:00
Andrey Samokhvalov
a14f25830e htlcswitch: remove redudant variables
Because processing of onion blob have been moved in another place we
could get rid of the variables which are not needed any more.

NOTE: pendingBatch have been replaced with batchCounter variable, but
it should be removed at all, because number of pending batch updates
might be counted by the state machine itself.
2017-05-31 11:06:08 -07:00
Andrey Samokhvalov
0e2209cb12 htlcswitch: move onion blob processing
Step №4 in making htlcManager (aka channelLink) testable:

This step consist of two:
1. Start using the hop iterator abstraction, the concrete
implementation of which will be added later, basically it will we the
same sphinx onion packet processor, but wrapped in hop iterator
abstraction.

2. The RevokAndAck processing part have been replaced by the
"processLockedInHtlcs" function which implement the same logic, but make
it a bit simpler.

Such changes will allow as to get rid of the the unnecessary variables.
2017-05-31 11:06:08 -07:00
Andrey Samokhvalov
de01721aed htlcswitch: add hop iterator
Short: such abstraction give as ability to test the channel link in the
future.

Long: hop iterator represents the entity which is be able to give payment
route hop by hop. This interface will be used to have an abstraction
over the algorithm which we use to determine the next hope in htlc route
and also helps the unit test to create mock representation of such
algorithm which uses simple array of hops.
2017-05-31 11:06:08 -07:00
Andrey Samokhvalov
db30571efe htlcswitch: start using config in channel link
Step №3 in making htlcManager (aka channelLink) testable:
Apply the channel link config inside the channel link itself.
2017-05-31 11:06:08 -07:00
Andrey Samokhvalov
2eea76375c htlcswitch: make channel link implements interface
Step №2 in making htlcManager (aka channelLink) testable:
Implement the ChannelLink interface which is needed to use it in pair
with htlc switch. With this commit channel link impelements interface,
but isn't able to operate properly yet.
2017-05-31 11:06:08 -07:00
Andrey Samokhvalov
7f572fc155 htlcswitch: add channel link config
Step №1 in making htlcManager (aka channelLink) testable:
Start use config which will allow as mock/stub external subsystems.
2017-05-31 11:06:08 -07:00
Andrey Samokhvalov
0de4ea2712 htlcswitch: copy the initial representation of htlc manager
In this commit all initial code which will be transformed into channel
link have been added. Rather than changing the in the same commit is
better to create the standalone commit, in order to see the changes
which have been applied to relocated code.
2017-05-31 11:06:08 -07:00