Commit Graph

132 Commits

Author SHA1 Message Date
Olaoluwa Osuntokun
b6f64932c2
htlcswitch: face race condition in unit tests by returning invoice
In this commit we modify the primary InvoiceRegistry interface within
the package to instead return a direct value for LookupInvoice rather
than a pointer. This fixes an existing race condition wherein a caller
could modify or read the value of the returned invoice.
2017-11-11 16:09:29 -08:00
Olaoluwa Osuntokun
1734f96544
lnwallet: add a set of unit tests to exercise the various ChanSync cases
In this commit, we’ve added a set of unit tests to cover all enumerated
channel sync scenarios, including the case where both nodes deem that
they’re unable to synchronize properly.
2017-11-10 19:51:01 -08:00
Olaoluwa Osuntokun
08c7fd9b4d
lnwallet: extend TestStateUpdatePersistence to assert proper htlc counters 2017-11-10 19:51:00 -08:00
Olaoluwa Osuntokun
32651e9311
lnwallet: revert commit 5240953de02d281be694b2c87d151d6c7dce2cb5
In this commit we revert a prior commit
(5240953de02d281be694b2c87d151d6c7dce2cb5) which was added as a stop
gap before we added the proper state needed to recover from cases where
the commitment transactions of both chains had diverged slightly due to
asymmetric dust limits.
2017-11-10 19:51:00 -08:00
Olaoluwa Osuntokun
e9d0e40a17
lnwallet: update existing channel unit tests to adhere to new channels API's 2017-11-10 19:51:00 -08:00
Olaoluwa Osuntokun
097e1c0f5c
lnwallet: update createTestChannels to adhere to new channeldb API's 2017-11-10 19:50:59 -08:00
Andrey Samokhvalov
e29193d550 htlcswitch+channel: remove cancel reasons from channel link 2017-11-09 16:38:58 -08:00
Jim Posen
a13ad0a339 multi: Fix various typos. 2017-10-25 13:20:54 -07:00
Olaoluwa Osuntokun
3b94e5df4d
lnwallet: introduce distinct HTLC counter+index on top of updateLog
In this commit, we fix an existing derivation from the commitment state
machine as defined within the specification. Before this commit, we
only kept a single counter which both HTLC adds and fails/settles would
share. This was valid in the prior pre-spec iteration of the state
machine. However in the current draft of the spec, only a distinct
counter for HTLCs are used throughout.

This would cause an incompatibility, as if we mixed adds and settles
during an exchange, then our counter values would differ with other
implementations. To remedy this, we now introduce a distinct HTLC
counter and index within the updateLog.

Each Add will increment both the log counter, and the HTLC counter.
Each Settle/Fail will only increment the log counter. Inbound
Settle/Fails will index into the HTLC index as to target the proper
HTLC. The PaymentDescriptor type has been extended with an additional
field (HltcIndex) which itself tracks the index of an incoming/outgoing
HTLC.
2017-10-22 18:36:57 -07:00
nsa
aa6395874d wallet: channel test fee fix for added HTLC
This commit fixes the TestChannelBalanceDustLimit unit test in
channel_test.go. The unit test does not account for the fees
required by adding an HTLC. As a result, Alice's balance according
to her local and remote commitment chains drops below 0 at certain
points. By using the correct fee, this is avoided.
2017-10-19 20:04:04 -07:00
Olaoluwa Osuntokun
d79c0ff95b
lnwallet: expand TestForceClose to ensure outgoing HTLC's can be swept
This commit expands the existing TestForceClose test case to add an
HTLC (outgoing) to Alice’s commitment transaction before force closing.
We then ensure that both the pre-signed timeout transaction _and_ the
sign descriptor to sweep the second-level output are fully valid.
2017-09-29 14:38:42 -07:00
Olaoluwa Osuntokun
927fb2ea0a
lnwallet: split off new TestForceCloseDustOutput case from TestForceClose
This commit extracts the ending dust adherence test case from the
existing TestForceClose test case into a distinct test case. With this
modification, we now ensure that the two new tests are focused and test
a single scenario at at time.
2017-09-29 14:13:28 -07:00
Olaoluwa Osuntokun
21d151d2ce
lnwallet: ensure the goroutines of all channels are stopped after test execution 2017-09-24 20:20:15 -07:00
Olaoluwa Osuntokun
9164cc218a
lnwallet: modify ReceiveFailHTLC to return value of HTLC failed 2017-09-24 20:17:53 -07:00
Olaoluwa Osuntokun
f576a74bf6
lnwallet: modify SettleHTLC to return value of HTLC settled
This commit adds an additional return value to SettleHTLC in order to
make way for an upcoming change to modify the way bandwidth status from
the link to the switch is reported.
2017-09-24 20:17:14 -07:00
Olaoluwa Osuntokun
2bf8d1b3fb
lnwallet: ensure all channel tests run in parallel 2017-09-24 20:14:30 -07:00
Olaoluwa Osuntokun
c85fcf2885
lnwallet: add test case for ErrInsufficientBalance error in channel state machine 2017-09-24 20:13:46 -07:00
Olaoluwa Osuntokun
a52d405998
lnwallet: ensure HTLC values are properly converted to SAT in commit tx
This commit fixes a bug within the HTLC construction and commitment
transaction construction that would result in HTLC _values_ within the
commitment transaction being off by a factor of 1000. This was due to
the fact that we failed to convert the amount of an HTLC, in mSAT, to
SAT before placing it as an output within the commitment transaction.
When attempt to locate the output index of a particular half, we use
the unconverted amount, meaning it was unnoticed.

This commit adds a new assertion within the TestSimpleAddSettleWorkflow
test to ensure that the HTLC is found within the commitment transaction
with the proper value in satoshi.
2017-08-30 15:34:18 -07:00
Olaoluwa Osuntokun
7f575b688e
multi: txscript.WitnessScript -> txscript.WitnessSignature 2017-08-24 18:55:32 -07:00
Olaoluwa Osuntokun
6e54aba7ac
lnwallet: convert channel state machine accounting to milli-satoshi 2017-08-22 00:52:50 -07:00
Johan T. Halseth
b9516b7cdd
lnwallet: make CreateCloseProposal take absolute fee instead of fee rate 2017-08-11 12:09:39 +02:00
Olaoluwa Osuntokun
5240953de0
lnwallet: temporarily ensure TestStateUpdatePersistence doesn't make dust
Note that this commit is temporary, and should be reverted once #231 is
merged. The reason we need to do this for now, is that we don’t
properly track the exact state of the remote party’s commitment. In
this test case, the resulting HTLC’s added are dust to one party, but
non-dust to another. So upon restart, the states (balance wise) has
diverged.
2017-07-31 20:53:08 -07:00
Olaoluwa Osuntokun
8c6a83a67d
lnwallet: account for second-level HTLC fee in TestChannelBalanceDustLimit 2017-07-31 20:50:54 -07:00
Olaoluwa Osuntokun
4aacf2b51d
lnwallet: ensure TestHTLCDustLimit also asserts for bob's commit chain 2017-07-31 20:50:12 -07:00
Olaoluwa Osuntokun
350e6d5c9f
lnwallet: extend TestDustHTLCFees to ensure dust HTLC's go to miners 2017-07-31 20:49:13 -07:00
Olaoluwa Osuntokun
00ca97c789
lnwallet: in TestForceClose properly assign Bob's balance 2017-07-31 20:44:22 -07:00
Olaoluwa Osuntokun
1b61341410
lnwallet: when creating channels in tests, properly account for commitment fee 2017-07-31 20:43:38 -07:00
Olaoluwa Osuntokun
747e0f57d1
multi: fix linter errors 2017-07-30 18:22:45 -07:00
Olaoluwa Osuntokun
6ad9d218b0
lnwallet: update all channel unittests due to new commitment design 2017-07-30 17:51:09 -07:00
Johan T. Halseth
ebe05f6568 lnwallet: add update_fee message support.
This commit adds the possibility for the initiator of a
channel to send the update_fee message, as specified
in BOLT#2. After the message is sent and both parties
have committed to the updated fee, all new commitment
messages in the channel will use the specified fee.
2017-07-14 16:39:15 -07:00
bryanvu
7fbb1e5a37 lnwallet: refactor dust limit tests
Split up and simplified dust limit tests.
2017-07-06 18:05:43 -07:00
bryanvu
73767f8c78 lnwallet: factor createHTLC out of unit tests 2017-07-06 18:05:43 -07:00
bryanvu
5068541044 lnwallet: apply dust HTLC amounts to fees
If an HTLC’s value is below a node’s dust limit, the amount for that
HTLC should be applied to to the fee used for the channel’s commitment
transaction.
2017-07-06 18:05:43 -07:00
Olaoluwa Osuntokun
1be4d67ce4
multi: run all test instances in parallel 2017-06-17 01:00:07 +02:00
Andrey Samokhvalov
79feebea80 channeldb: remove redudant test
After addition of the bidirectional payment test in htlcswitch packet,
which is more abstract, we may remove redudant test.
2017-05-31 11:06:08 -07:00
Andrey Samokhvalov
dbcce82d52 lnwallet: make DeriveRevocationRoot public
In order to be able to use the DeriveRevocationRoot in the createChannel
function inside the htlcswicth package we need to make it public.

NOTE: The original lnwallet.CreateChannel function haven't been
sufficient as far it not takes the private keys as input.
2017-05-31 11:06:08 -07:00
bryanvu
408be356fb lnwallet: update channel close to use fee estimation interface
This commit switches the channel close workflow to use the lnwallet fee
estimation interface rather than the hardcoded proposedFee.
2017-05-23 14:31:20 -07:00
bryanvu
514760f529 peer: handling for channel shutdown messages
This commit changes the cooperative channel close workflow to comply
with the latest spec. This adds steps to handle and send shutdown
messages as well as moving responsibility for sending the channel close
message from the initiator to the responder.
2017-05-23 14:31:20 -07:00
Olaoluwa Osuntokun
e689ef61dd
lnwallet: when calc'ing fee for commitment tx, use current fee-per-kw
This commit modifies the fee calculation logic when creating or
accepting a new commitment transaction to use the set FeePerKw within
the channel rather then re-query the estimator each time. The prior
behavior was benign as we currently use a static fee estimator, but the
dynamic setting this could’ve caused a state divergence.
2017-05-16 19:05:18 -07:00
Olaoluwa Osuntokun
222385bf73
lnwallet: calcStaticFee now directly uses feePerKw 2017-05-16 18:56:46 -07:00
bryanvu
4ac7cc719f lnwallet: replace hard-coded fees and adjust tests accordingly
This commit replaces the hard-coded 5000 satoshi fees with calls to the
FeeEstimator interface. This should provide a way to cleanly plug in
additional fee calculation algorithms in the future. This change
affected quite a few tests. When possible, the tests were changed to
assert amounts sent rather than balances so that fees wouldn't need to
be taken into account. There were several tests for which this wasn't
possible, so calls to the static fee calculator were made.
2017-05-15 20:26:11 -07:00
bryanvu
abe2e502d5 lnwallet: add FeeEstimator interface, StaticFeeEstimator implementation
This commit adds the FeeEstimator interface, which can be used for
future fee calculation implementations. Currently, there is only the
StaticFeeEstimator implementation, which returns the same fee rate for
any transaction.
2017-05-15 20:26:11 -07:00
bryanvu
c1769f959b lnwallet: fix failure messages, spacing in tests
This commit changes t.Fatal to t.Fatalf in TestCheckDustLimit so as to
provide more information. This commit also makes some column width
adjustments and minor spelling/formatting changes.
2017-05-15 20:26:11 -07:00
Olaoluwa Osuntokun
2486097554
discovery+lnwallet: fix tests by making mock notifiers compliant to new interface 2017-05-11 15:58:41 -07:00
Olaoluwa Osuntokun
a8671c485f
lnwallet: properly observe dust limits during cooperative chan closure
This commit fixes a lingering TODO within the wallet portion of the
codebase by properly adhering to the set dust limits when closing a
channel. With this new commit if a party’s current settled balance is
below their current dust-limit, then it will be omitted from the
commitment transaction.

The prior test that asserted negative outputs are rejected has been
removed as they’ll now be avoided by ensuring we omit dust outputs from
the commitment transaction.
2017-03-24 16:20:12 -07:00
Christopher Jämthagen
e524b7ac81 test: change HTLC amount in persistent test to account for dust 2017-03-21 21:21:46 -07:00
Olaoluwa Osuntokun
ec52c49b6c
lnd+lnwallet+glide: replace last lingering instances of fastsha256 2017-03-16 19:40:29 -07:00
Olaoluwa Osuntokun
f217093c00
multi: replace usage of fastsha256 with crypto/sha256
This commit removes all instances of the fastsha256 library and
replaces it with the sha256 library in the standard library. This
change should see a number of performance improvements as the standard
library has highly optimized assembly instructions with use vectorized
instructions as the platform supports.
2017-03-15 18:56:41 -07:00
Christopher Jämthagen
810d8c286e test: add TestForceClose for lnwallet package 2017-03-09 15:32:31 -08:00
Christopher Jämthagen
52b56b8cf2 lnwallet+test: no dust outputs in commitment transaction + tests
Currently non-HTLC outputs will be accepted in the commitment
transaction as long as it is non-zero. We change this by not allowing
outputs with a value lower than the dust limit. The value of such
an output will go towards transaction fees.
2017-03-09 15:32:31 -08:00
Olaoluwa Osuntokun
fc54c5d8d8
lnwallet: perform sanity check on cooperative closure transacitons
This commit fixes a class of bug that currently exists within the
cooperative closure methods for the channel state machine. As an
example, due to the current hard coded fees, if one of the outputs
generated within the generated closure transaction has a negative
output, then the initiating node would gladly forward this to the
remote node. The remote node would then reject the closure as the
transaction is invalid. However, the act of completing the closure
would cause the remote node’s state machine to shift into a “closed”
state. As a result, any further closure attempts by the first node
(force or regular) would go unnoticed by the remote node.

We fix this issue by ensuring the transaction is “sane” before
initiating of completing a cooperative channel closure.

At test case has been added exercising the particular erroneous case
reported by “moli” on IRC.
2017-02-27 21:00:25 -06:00
Olaoluwa Osuntokun
9adc5f6484
lnwallet+channeldb: update callers to shachain API changes 2017-02-24 16:31:45 -08:00
Andrey Samokhvalov
f86557c3e4 channeldb+lnwallet: replace elkrem with shachain
In this commit the initial implementation of revocation hash
generation 'elkrem' was replaced with 'shachain' Rusty Russel
implementation which currently enshrined in the spec. This alghoritm has
the same asymptotic characteristics but has more complex scheme
to determine wish hash we can drop and what needs to be stored
in order to be able to achive full compression.
2017-02-22 16:49:29 -08:00
Olaoluwa Osuntokun
caa464f33b
lnwallet: update channel state machine tests to latest changes
This commit updates the set of channel state machine tests to properly
compile and execute with the latest set of changes to the state
machine.

Most of the changes within this commit are just renaming and field
changes as a result of the new wire messages.

The more substantial change is due to the change in semantics of the
new state machine w.r.t what has and has not been ACK’d when a new
state transition is implemented. In the case of a concurrent update
(both sides add to the log before a state transition), both sides need
to trigger  a state update in order to ensure their updates have been
included.
2017-02-21 01:43:18 -08:00
Olaoluwa Osuntokun
f4b403679b
lnwallet: remove BlockChainIO as a dependency to LightningChannel
This commit removes the BlockChainIO interface as a dependency to the
LightningChannel struct as the interface is no longer used within the
operation of the LightningChannel.
2017-02-02 17:05:40 -08:00
Trevin Hofmann
40c7bac3aa multi: fix a variety of typos throughout the repo 2017-01-17 17:02:56 -08:00
Olaoluwa Osuntokun
c9dbaa1403
lnwallet: include r-hash of canceled htlc in log entry for cancel
This commit modifies the logic around adding cancel entries to the
update log for the commitment state machine slightly by also including
the r-hash of the HTLC that’s been cancelled in the entry for the
cancellation. With this change, we can accurately track which HTLC is
being cancelled within outer sub-systems.
2017-01-07 21:22:01 -08:00
Olaoluwa Osuntokun
9bb5a45f89
lnwallet: the canceller of an HTLC targets by payment hash not index
This commit alters the new HTLC cancellation logic to instead allow the
canceller of an HTLC to cancel the HTLC by the payment hash rather than
the index of the HTLC.
2017-01-07 21:20:57 -08:00
Olaoluwa Osuntokun
fd0c0574e6
lnwallet: add send/recv of HTLC cancellations to state machine
This commit adds the ability to send/recv HTLC cancellation to the
commitment state machine. Previously this feature had been
unimplemented within the state machine, with only adds/settles working.

With this change, there’s now now no concept of “timing” out HTLC’s,
only the cancellation of HTLC’s which may be triggered for various
reasons.
2017-01-07 21:20:51 -08:00
Olaoluwa Osuntokun
5affed38fc
multi: update btcsuite API's to latest upstream changes
This commit makes a large number of minor changes concerning API usage
within the deamon to match the latest version on the upstream btcsuite
libraries.

The major changes are the switch from wire.ShaHash to chainhash.Hash,
and that wire.NewMsgTx() now takes a paramter indicating the version of
the transaction to be created.
2017-01-05 13:56:34 -08:00
Olaoluwa Osuntokun
597b4ee3d3
channeldb: Open is no longer dependant on a specific set of chain params 2016-12-27 16:43:19 -08:00
Andrey Samokhvalov
d01f1b5ff4 fundingmanager+lnwallet: add HTLC dust limit logic 2016-12-13 11:01:57 -08:00
Andrey Samokhvalov
5a82240c6a lnwire+lnwallet+fundingmanager: general improvements 2016-12-13 11:01:57 -08:00
Andrey Samokhvalov
da3028e10c lnwallet: add HTLC count validation 2016-11-23 20:02:29 -06:00
Andrey Samokhvalov
391d5cd401 lnwallet: add commitment transaction estimation 2016-11-23 20:02:29 -06:00
Andrey Samokhvalov
5b9e4ae61e general: fix typos, rename variables, add comments 2016-11-23 20:02:29 -06:00
bryanvu
faf9daddf6 lnwallet: calculate channel's total satoshis sent and received
When HTLCs are settled, the channel’s TotalSatoshisSent and
TotalSatoshisReceived fields are updated.
2016-11-22 14:57:03 -06:00
Olaoluwa Osuntokun
c81e0a3ebb
lnwallet: convert CommitSpendRevoke+CommitSpendNoDelay to use Signer
This commit converts the rearming two commitment spend functions to use
the lnwallet.Signer interface directly rather than manually manage
private keys during the signing process. This commit is in preparation
for implementation of fully automated revoked uncooperative closure
detection and retribution.
2016-11-18 15:23:50 -08:00
Olaoluwa Osuntokun
74122a0901
lnwallet: encode obfuscated state hints in the commitment tx
This commit modifies the channel state machine slightly to encode the
current state number using 30-bits of the sequence number within the
commitment transaction’s only input.

Such a modification reduces up the processing time required to punish
the counter party for breaching the contract established within the
channel by broadcasting an older revoked state.

This fixes #58 with a minor modification to what was originally
suggested.
2016-11-16 12:49:44 -08:00
Olaoluwa Osuntokun
6e01bb72b0
lnwallet+peer: minor typo fixes 2016-11-14 15:06:17 -08:00
Olaoluwa Osuntokun
e1d9d9c8d2
lnwallet: update to adhere to new channeldb API change
This commit modifies the lnwallet code and related tests in order to
adhere to the recent field-name change to channeldb.OpenChannel.
Instead of having the field ‘TheirLNID’ which is the sha256 of the
node’s public key, we now instead use the public key directly in all
contexts.
2016-10-25 16:41:22 -07:00
Andrey Samokhvalov
14c6770b76 general: fix typos 2016-10-22 01:48:05 +03:00
andrew.shvv
e515710a7d multi: use witnessScript everywhere instead of redeemScript
This commit consists of a mass variable renaming to call the pkScript being executed for segwit outputs the `witnessScript` instead of `redeemScript`. The latter naming convention is generally considered to be reserved for the context of BIP 16 execution. With segwit to be deployed soon, we should be using the correct terminology uniformly through the codebase. 

In addition some minor typos throughout the codebase has been fixed.
2016-10-15 16:02:09 -07:00
Olaoluwa Osuntokun
49ce1040d4
lnwallet: adopt simple fee structure for commitment transactions
This commit modifies the prior funding workflow to account for fees
when creating the funding output. As a stop gap, the current fee for
the commitment transaction is now hard-coded at 5k satoshis. Once the
fee models are in place this should instead be some high multiple of
the current “average” fee rate within the network, continuing, the
proper fee should be adjusted from the commitment transaction has
outputs are added/removed.
2016-09-12 19:08:01 -07:00
Olaoluwa Osuntokun
affd7793b3
lnwallet: add htlc persistence, state log restoration to channel state machine
This commit adds full persistence logic of the current lowest
un-revoked height within each commitment chain. The newly added
channeldb methods for record state transitions within both commitment
chains are now utilized. This un-settled HTLC state is now read upon
initialization, with the proper log entries inserted into the state
update log which reflect the garbage collected log right before the
restart.

A new set of tests have been added to exercise a few edge cases around
HTLC persistence to ensure the in-memory log is properly restored based
on the on-disk snapshot.
2016-09-12 19:07:04 -07:00
Olaoluwa Osuntokun
671098325d
lnwallet: refactor all wallet/channel interaction to use the WalletController.
This commit performs a major refactor of the current wallet,
reservation, and channel code in order to call into a WalletController
implementation rather than directly into btcwallet.

The current set of wallets tests have been modified in order to test
against *all* registered WalletController implementations rather than
only btcwallet. As a result, all future WalletControllers primary need
to ensure that their implementation passes the current set of tests
(which will be expanded into the future), providing an easy path of
integration assurance.

Rather than directly holding the private keys throughout funding and
channel creation, the burden of securing keys has been shifted to the
specified WalletController and Signer interfaces. All signing is done
via the Signer interface rather than directly, increasing flexibility
dramatically.

During channel funding, rather than creating a txscript.Engine to
verify commitment signatures, regular ECDSA sig verification is now
used instead. This is faster and more efficient.

Finally certain fields/methods within ChannelReservation and
LightningChannel have been exposed publicly in order to restrict the
amount of modifications the prior tests needed to undergo in order to
support testing directly agains the WalletController interface.
2016-09-08 12:25:54 -07:00
Olaoluwa Osuntokun
c0614c0478
lnwallet: add basic tests for cooperative channel closure
This commit adds a basic test for cooperative channel closure. The
current test ensures correctness of the cooperative closure procedure
initiated by either the channel initiator, or the channel responder.
2016-07-27 11:32:35 -07:00
Olaoluwa Osuntokun
4063171918
lnwallet: partition state update logs within channel state machine
This commit patrons the state update logs properly within the channel
state machine. This change fixes a number of bugs caused by treating a
central log as two logically distinct logs. Rather than having a bit
indicating if the entry is incoming/outgoing, an entry is added to a
remote or local log depending on which modification method is used.

As a result the code is much easier to follow due to separation of
concerts.

Finally, when attempting to sign a new update with an exhausted
renovation window a distinct error is returned in order to allow higher
level callers to properly back-off and handle the protocol event.
2016-07-21 16:50:38 -07:00
Olaoluwa Osuntokun
b60270f3f7
lnwallet: include htlcs to settle in returned set of htlc's to forward
This commit fixes a slight bug in the channel state machine’s code
executed when processing a revocation messages. With this commit after
processing a revocation, log entries which we should forward to the
downstream or upstream peer for settling/adding HTLC’s are now properly
returned.

The testa have also been updated to ensure to correct htlc’s are
returned “for forwarding”.
2016-07-16 18:12:49 -07:00
Olaoluwa Osuntokun
2c303a1879
lnwallet: AddHTLC now returns log index of created log entry 2016-07-16 18:02:09 -07:00
Olaoluwa Osuntokun
7dea354711
lnwallet: properly handle HTLC settles in channel state-machine
We no longer track HTLC’s by their r-hash within the log into the
index, as we may have multiple HTLC’s that can be redeemed by the same
pre-image. Instead we now use a separate index which is keyed by a
log-index.

Additionally, the SettleHTLC method now also returns the index of the
HTLC being settled which allows the remote party to quickly locate the
HTLC within their log.

This commit also introduces a few trace/debug log messages which will
likely be pruned in the near future
2016-07-12 17:35:57 -07:00
Olaoluwa Osuntokun
94c242073a
lnwallet: finish initial draft of LightningChannel state machine
This commit finishes the initial draft of the commitment state machine.
A full re-write of the prior protocol which combines aspects of the
former ‘lnstate’ package has replaced the prior un-finished
stop-and-wait protocol.

This new protocol is designed to operate in an asynchronous environment
and to facilitate non-blocking batched and pipelined updates to the
committed channel states. The protocol is also de-synchronized meaning
that either side can propose new commitment states independent of the
actions of the other party.

The state machine implemented is very similar to that of c-lightning,
however we allow multiple unrevoked commentates in order to minimize
blocking, and also to reduce latency across several hops in a
bi-directional setting.

The current implementation consists of 3 main data structures: a
commitment chain which consist of unrevoked commitment transactions
(one for each side), and a (mostly) append-only log of HTLC updates
shared between both sides. New commitments proposed index into the log
denoting which updates they include, this allows both parties to
progress chains independent of one another. Revoked commitments, reduce
the length of the chain by one, and free up space within the revocation
window.

At this point only basic tests are in place for the state machine,
however more extensive testing infrastructure along with formal proofs
using PlusCall are planned.
2016-07-05 17:02:03 -07:00