Commit graph

122 commits

Author SHA1 Message Date
Luke Parker
369af0fab5
\#339 addendum 2023-11-15 20:23:19 -05:00
Luke Parker
96f1d26f7a
Add a cosigning protocol to ensure finalizations are unique (#433)
* Add a function to deterministically decide which Serai blocks should be co-signed

Has a 5 minute latency between co-signs, also used as the maximal latency
before a co-sign is started.

* Get all active tributaries we're in at a specific block

* Add and route CosignSubstrateBlock, a new provided TX

* Split queued cosigns per network

* Rename BatchSignId to SubstrateSignId

* Add SubstrateSignableId, a meta-type for either Batch or Block, and modularize around it

* Handle the CosignSubstrateBlock provided TX

* Revert substrate_signer.rs to develop (and patch to still work)

Due to SubstrateSigner moving when the prior multisig closes, yet cosigning
occurring with the most recent key, a single SubstrateSigner can be reused.
We could manage multiple SubstrateSigners, yet considering the much lower
specifications for cosigning, I'd rather treat it distinctly.

* Route cosigning through the processor

* Add note to rename SubstrateSigner post-PR

I don't want to do so now in order to preserve the diff's clarity.

* Implement cosign evaluation into the coordinator

* Get tests to compile

* Bug fixes, mark blocks without cosigners available as cosigned

* Correct the ID Batch preprocesses are saved under, add log statements

* Create a dedicated function to handle cosigns

* Correct the flow around Batch verification/queueing

Verifying `Batch`s could stall when a `Batch` was signed before its
predecessors/before the block it's contained in was cosigned (the latter being
inevitable as we can't sign a block containing a signed batch before signing
the batch).

Now, Batch verification happens on a distinct async task in order to not block
the handling of processor messages. This task is the sole caller of verify in
order to ensure last_verified_batch isn't unexpectedly mutated.

When the processor message handler needs to access it, or needs to queue a
Batch, it associates the DB TXN with a lock preventing the other task from
doing so.

This lock, as currently implemented, is a poor and inefficient design. It
should be modified to the pattern used for cosign management. Additionally, a
new primitive of a DB-backed channel may be immensely valuable.

Fixes a standing potential deadlock and a deadlock introduced with the
cosigning protocol.

* Working full-stack tests

After the last commit, this only required extending a timeout.

* Replace "co-sign" with "cosign" to make finding text easier

* Update the coordinator tests to support cosigning

* Inline prior_batch calculation to prevent panic on rotation

Noticed when doing a final review of the branch.
2023-11-15 16:57:21 -05:00
David Bell
c328e5ea68
Convert coordinator/tributary/nonce_decider to use create_db macro (#423)
* chore: convert nonce_deicer to use create_db macro

* Restore pub NonceDecider

* Remove extraneous comma

I forgot to run git commit --amend on the prior commit :/

---------

Co-authored-by: Luke Parker <lukeparker5132@gmail.com>
2023-11-12 12:04:34 -05:00
Luke Parker
54f1929078
Route blame between Processor and Coordinator (#427)
* Have processor report errors during the DKG to the coordinator

* Add RemoveParticipant, InvalidDkgShare to coordinator

* Route DKG blame around coordinator

* Allow public construction of AdditionalBlameMachine

Necessary for upcoming work on handling DKG blame in the processor and
coordinator.

Additionally fixes a publicly reachable panic when commitments parsed with one
ThresholdParams are used in a machine using another set of ThresholdParams.

Renames InvalidProofOfKnowledge to InvalidCommitments.

* Remove unused error from dleq

* Implement support for VerifyBlame in the processor

* Have coordinator send the processor share message relevant to Blame

* Remove desync between processors reporting InvalidShare and ones reporting GeneratedKeyPair

* Route blame on sign between processor and coordinator

Doesn't yet act on it in coordinator.

* Move txn usage as needed for stable Rust to build

* Correct InvalidDkgShare serialization
2023-11-12 07:24:41 -05:00
Luke Parker
c03fb6c71b
Add dedicated BatchSignId 2023-11-06 20:06:36 -05:00
Luke Parker
e05b77d830
Support multiple key shares per validator (#416)
* Update the coordinator to give key shares based on weight, not based on existence

Participants are now identified by their starting index. While this compiles,
the following is unimplemented:

1) A conversion for DKG `i` values. It assumes the threshold `i` values used
will be identical for the MuSig signature used to confirm the DKG.
2) Expansion from compressed values to full values before forwarding to the
processor.

* Add a fn to the DkgConfirmer to convert `i` values as needed

Also removes TODOs regarding Serai ensuring validator key uniqueness +
validity. The current infra achieves both.

* Have the Tributary DB track participation by shares, not by count

* Prevent a node from obtaining 34% of the maximum amount of key shares

This is actually mainly intended to set a bound on message sizes in the
coordinator. Message sizes are amplified by the amount of key shares held, so
setting an upper bound on said amount lets it determine constants. While that
upper bound could be 150, that'd be unreasonable and increase the potential for
DoS attacks.

* Correct the mechanism to detect if sufficient accumulation has occured

It used to check if the latest accumulation hit the required threshold. Now,
accumulations may jump past the required threshold. The required mechanism is
to check the threshold wasn't prior met and is now met.

* Finish updating the coordinator to handle a multiple key share per validator environment

* Adjust stategy re: preventing noce reuse in DKG Confirmer

* Add TODOs regarding dropped transactions, add possible TODO fix

* Update tests/coordinator

This doesn't add new multi-key-share tests, it solely updates the existing
single key-share tests to compile and run, with the necessary fixes to the
coordinator.

* Update processor key_gen to handle generating multiple key shares at once

* Update SubstrateSigner

* Update signer, clippy

* Update processor tests

* Update processor docker tests
2023-11-04 19:26:13 -04:00
Luke Parker
a300a1029a
Load/save first_preprocess with RecognizedIdType
Enables their IDs to have conflicts across each other.
2023-10-14 21:58:10 -04:00
Luke Parker
19e90b28b0
Have Tributary's add_transaction return a proper error
Modifies main.rs to properly handle the returned error.
2023-10-14 21:50:11 -04:00
Luke Parker
584943d1e9
Modify SubstrateBlockAck as needed
Replaces plan IDs with key + ID, letting the coordinator determine the sessions
for the plans.

Properly scopes which plan IDs are set on which tributaries, and ensures we
have the necessary tributaries at time of handling.
2023-10-14 20:37:54 -04:00
Luke Parker
62e1d63f47
Abort the P2P meta task when dropped
This should cause full cleanup of all Tributary async tasks, since the machine
already cleans itself up on drop.
2023-10-14 20:08:51 -04:00
Luke Parker
e4adaa8947
Further tweaks re: retiry 2023-10-14 19:55:14 -04:00
Luke Parker
3b3fdd104b
Most of coordinator Tributary retiry
Adds Event::SetRetired to validator-sets.

Emit TributaryRetired.

Replaces is_active_set, which made multiple network requests, with
is_retired_tributary, a DB read.

Performs most of the removals necessary upon TributaryRetired.

Still needs to clean up the actual Tributary/Tendermint tasks.
2023-10-14 16:47:25 -04:00
Luke Parker
f414735be5
Redo new_tributary from being over ActiveTributary to TributaryEvent
TributaryEvent also allows broadcasting a retiry event.
2023-10-14 15:27:39 -04:00
Luke Parker
530fba51dd Update coordinator to new serai-client 2023-10-14 15:26:36 -04:00
Luke Parker
96cc5d0157
Remove a TODO re: an unhandled race condition 2023-10-14 00:41:07 -04:00
Luke Parker
7275a95907
Break handle_processor_messages out to handle_processor_message, move a helper fn to substrate 2023-10-13 23:36:07 -04:00
Luke Parker
80e5ca9328
Move heartbeat_tributaries and handle_p2p to p2p.rs 2023-10-13 22:40:11 -04:00
Luke Parker
67951c4971
Localize scan_substrate as substrate::scan_task 2023-10-13 22:31:54 -04:00
Luke Parker
4143fe9f47
Move scan_tributaries, shrinking coordinator's main.rs 2023-10-13 22:30:13 -04:00
Luke Parker
97c328e5fb
Check tributaries are active before declaring them relevant 2023-10-13 21:46:17 -04:00
akildemir
d5c6ed1a03
Improve provided handling (#381)
* fix typos

* remove tributary sleeping

* handle not locally provided txs

* use topic number instead of waiting list

* Clean-up, fixes

1) Uses a single TXN in provided
2) Doesn't continue on non-local provided inside verify_block, skipping further
   execution of checks
3) Upon local provision of already on-chain TX, compares

---------

Co-authored-by: Luke Parker <lukeparker5132@gmail.com>
2023-10-13 19:45:47 -04:00
Luke Parker
f6e8bc3352
Alternate handover batch TOCTOU fix (#397)
* Revert "Correct the prior documented TOCTOU"

This reverts commit d50fe87801.

* Correct the prior documented TOCTOU

d50fe87801 edited the challenge for the Batch to
fix it. This won't produce Batch n+1 until Batch n is successfully published
and verified. It's an alternative strategy able to be reviewed, with a much
smaller impact to scope.
2023-10-13 12:14:59 -04:00
Luke Parker
d50fe87801
Correct the prior documented TOCTOU
Now, if a malicious validator set publishes a malicious `Batch` at the last
moment, it'll cause all future `Batch`s signed by the next validator set to
require a bool being set (yet they never will set it).

This will prevent the handover.

The only overhead is having two distinct `batch_message` calls on-chain.
2023-10-13 04:41:01 -04:00
Luke Parker
e6aa9df428
Document TOCTOU allowing malicious validator set to trigger a handover to an honest set 2023-10-13 04:14:36 -04:00
Luke Parker
02edfd2935
Verify all Batchs published by the prior set
The new set publishing a `Batch` completes the handover protocol. The new set
should only publish a `Batch` once it believes the old set has completed all of
its on-external-chain activity, marking it honest and finite.

With the handover comes the acceptance of liability, hence the requirement for
all of the on-Serai-chain activity also needing verification. While most
activity would be verified in-real-time (upon ::Batch messages), the new set
will now explicitly verify the complete set of `Batch`s before beginning its
preprocess for its own `Batch` (the one accepting the handover).
2023-10-13 04:12:21 -04:00
Luke Parker
6a4c57e86f
Define an array of all NetworkIds in serai_primitives 2023-10-12 23:59:21 -04:00
Luke Parker
15edea1389
Use an inner task to spawn Tributarys to minimize latency 2023-10-12 21:55:25 -04:00
Luke Parker
f25f5cd368
Add a sleep statement to Batch publication errors to prevent log flooding/node hammering 2023-10-12 18:39:46 -04:00
Luke Parker
13cbc99149
Properly define the on-chain handover protocol
The new key publishing `Batch`s is more than sufficient.

Also uses the correct key to verify the published `Batch`s authenticity.
2023-10-10 23:55:59 -04:00
Luke Parker
1a0b4198ba
Correct the check for if we still need to set keys
The prior check had an edge case where once keys were pruned, it'd believe the
keys needed to be set ad infinitum.
2023-10-10 22:53:15 -04:00
akildemir
98190b7b83
Staking pallet (#373)
* initial staking pallet

* add staking pallet to runtime

* support session rotation for serai

* optimizations & cleaning

* fix deny

* add serai network to initial networks

* a few tweaks & comments

* fix some pr comments

* Rewrite validator-sets with logarithmic algorithms

Uses the fact the underlying DB is sorted to achieve sorting of potential
validators by stake.

Removes release of deallocated stake for now.

---------

Co-authored-by: Luke Parker <lukeparker5132@gmail.com>
2023-10-10 06:53:24 -04:00
Luke Parker
30d0bad175
Add extra assert to coordinator 2023-10-09 23:38:39 -04:00
Luke Parker
bd5491dfd5
Simply Coordinator/Processors::send by accepting impl Into *Message 2023-09-29 04:19:59 -04:00
Luke Parker
0eff3d9453
Add Batch messages from processor, verify Batchs published on-chain
Renames Update to SignedBatch.

Checks Batch equality via a hash of the InInstructions. That prevents needing
to keep the Batch in node state or TX introspect.
2023-09-29 03:51:01 -04:00
Luke Parker
83b3a5c31c
Document how receiving a Processor message does indeed make its Tributary relevant 2023-09-28 20:09:17 -04:00
Luke Parker
7d738a3677
Start moving Coordinator to a multi-Tributary model
Prior, we only supported a single Tributary per network, and spawned a task to
handled Processor messages per Tributary. Now, we handle Processor messages per
network, yet we still only supported a single Tributary in that handling
function.

Now, when we handle a message, we load the Tributary which is relevant. Once we
know it, we ensure we have it (preventing race conditions), and then proceed.

We do need work to check if we should have a Tributary, or if we're not
participating. We also need to check if a Tributary has been retired, meaning
we shouldn't handle any transactions related to them, and to clean up retired
Tributaries.
2023-09-27 20:49:02 -04:00
Luke Parker
01a4b9e694
Remove unused_variables 2023-09-27 13:00:04 -04:00
Luke Parker
3b01d3039b
Remove unused clippy lints from coordinator 2023-09-27 12:42:25 -04:00
Luke Parker
40b7bc59d0
Use dedicated Queues for each from-to pair
Prevents one Processor's message from halting the entire pipeline.
2023-09-27 12:20:57 -04:00
Luke Parker
269db1c4be
Remove the "expected" next ID
It's an unnecessary extra layer better handled locally.
2023-09-27 11:13:55 -04:00
Luke Parker
90318d7214
Remove unnecessary TODO 2023-09-27 00:50:57 -04:00
Luke Parker
64d370ac11
Make publish_signed_transaction safe for out of order publications
This is a possibility under the new deterministic nonce scheme.

While there is a concern of us never creating a transaction with a nonce,
blocking everything, we should always create transactions. We'll always publish
preprocesses, and while we'll only publish shares if everyone else does, we
only allocate for shares once everyone else does.
2023-09-27 00:44:31 -04:00
Luke Parker
db8dc1e864
Spawn a task for Heartbeat responses, preventing it from holding up P2P handling 2023-09-27 00:10:37 -04:00
Luke Parker
086458d041
Txn for handling a processor message
handle_processor_messages function added to remove a very large block of nested
code.

MainDb cleaned to never be instantiated.
2023-09-27 00:00:31 -04:00
Luke Parker
2e0f8138e2
Update the coordinator to not handle a processor message multiple times 2023-09-26 23:28:05 -04:00
Luke Parker
2508633de9
Add a next block notification system to Tributary
Also adds a loop missing from the prior commit.
2023-09-25 23:20:51 -04:00
Luke Parker
7312428a44
P2P task per Tributary, not per message 2023-09-25 22:58:40 -04:00
Luke Parker
e1801b57c9
Dedicated tasks per-Processor in coordinator
This isn't meaningful yet, as we still have serialized reading messages from
Processors, yet is a step closer.
2023-09-25 22:38:29 -04:00
Luke Parker
60491a091f
Improve handling of tasks in coordinator, one per Tributary scanner 2023-09-25 20:33:14 -04:00
Luke Parker
9f3840d1cf
Localize Tributary HashMaps, offering flexibility and removing contention 2023-09-25 19:28:53 -04:00