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3 commits

Author SHA1 Message Date
Luke Parker
e2571a43aa
Correct processor flow to have the coordinator decide signing set/re-attempts
The signing set should be the first group to submit preprocesses to Tributary.
Re-attempts shouldn't be once every 30s, yet n blocks since the last relevant
message.

Removes the use of an async task/channel in the signer (and Substrate signer).
Also removes the need to be able to get the time from a coin's block, which was
a fragile system marked with a TODO already.
2023-04-15 23:01:07 -04:00
Luke Parker
7abc8f19cd
Move substrate/serai/* to substrate/* 2023-04-08 03:01:14 -04:00
Luke Parker
ba82dac18c
Processor (#259)
* Initial work on a message box

* Finish message-box (untested)

* Expand documentation

* Embed the recipient in the signature challenge

Prevents a message from A -> B from being read as from A -> C.

* Update documentation by bifurcating sender/receiver

* Panic on receiving an invalid signature

If we've received an invalid signature in an authenticated system, a 
service is malicious, critically faulty (equivalent to malicious), or 
the message layer has been compromised (or is otherwise critically 
faulty).

Please note a receiver who handles a message they shouldn't will trigger 
this. That falls under being critically faulty.

* Documentation and helper methods

SecureMessage::new and SecureMessage::serialize.

Secure Debug for MessageBox.

* Have SecureMessage not be serialized by default

Allows passing around in-memory, if desired, and moves the error from 
decrypt to new (which performs deserialization).

Decrypt no longer has an error since it panics if given an invalid 
signature, due to this being intranet code.

* Explain and improve nonce handling

Includes a missing zeroize call.

* Rebase to latest develop

Updates to transcript 0.2.0.

* Add a test for the MessageBox

* Export PrivateKey and PublicKey

* Also test serialization

* Add a key_gen binary to message_box

* Have SecureMessage support Serde

* Add encrypt_to_bytes and decrypt_from_bytes

* Support String ser via base64

* Rename encrypt/decrypt to encrypt_bytes/decrypt_to_bytes

* Directly operate with values supporting Borsh

* Use bincode instead of Borsh

By staying inside of serde, we'll support many more structs. While 
bincode isn't canonical, we don't need canonicity on an authenticated, 
internal system.

* Turn PrivateKey, PublicKey into structs

Uses Zeroizing for the PrivateKey per #150.

* from_string functions intended for loading from an env

* Use &str for PublicKey from_string (now from_str)

The PrivateKey takes the String to take ownership of its memory and 
zeroize it. That isn't needed with PublicKeys.

* Finish updating from develop

* Resolve warning

* Use ZeroizingAlloc on the key_gen binary

* Move message-box from crypto/ to common/

* Move key serialization functions to ser

* add/remove functions in MessageBox

* Implement Hash on dalek_ff_group Points

* Make MessageBox generic to its key

Exposes a &'static str variant for internal use and a RistrettoPoint 
variant for external use.

* Add Private to_string as deprecated

Stub before more competent tooling is deployed.

* Private to_public

* Test both Internal and External MessageBox, only use PublicKey in the pub API

* Remove panics on invalid signatures

Leftover from when this was solely internal which is now unsafe.

* Chicken scratch a Scanner task

* Add a write function to the DKG library

Enables writing directly to a file.

Also modifies serialize to return Zeroizing<Vec<u8>> instead of just Vec<u8>.

* Make dkg::encryption pub

* Remove encryption from MessageBox

* Use a 64-bit block number in Substrate

We use a 64-bit block number in general since u32 only works for 120 years
(with a 1 second block time). As some chains even push the 1 second threshold,
especially ones based on DAG consensus, this becomes potentially as low as 60
years.

While that should still be plenty, it's not worth wondering/debating. Since
Serai uses 64-bit block numbers elsewhere, this ensures consistency.

* Misc crypto lints

* Get the scanner scratch to compile

* Initial scanner test

* First few lines of scheduler

* Further work on scheduler, solidify API

* Define Scheduler TX format

* Branch creation algorithm

* Document when the branch algorithm isn't perfect

* Only scanned confirmed blocks

* Document Coin

* Remove Canonical/ChainNumber from processor

The processor should be abstracted from canonical numbers thanks to the
coordinator, making this unnecessary.

* Add README documenting processor flow

* Use Zeroize on substrate primitives

* Define messages from/to the processor

* Correct over-specified versioning

* Correct build re: in_instructions::primitives

* Debug/some serde in crypto/

* Use a struct for ValidatorSetInstance

* Add a processor key_gen task

Redos DB handling code.

* Replace trait + impl with wrapper struct

* Add a key confirmation flow to the key gen task

* Document concerns on key_gen

* Start on a signer task

* Add Send to FROST traits

* Move processor lib.rs to main.rs

Adds a dummy main to reduce clippy dead_code warnings.

* Further flesh out main.rs

* Move the DB trait to AsRef<[u8]>

* Signer task

* Remove a panic in bitcoin when there's insufficient funds

Unchecked underflow.

* Have Monero's mine_block mine one block, not 10

It was initially a nicety to deal with the 10 block lock. C::CONFIRMATIONS
should be used for that instead.

* Test signer

* Replace channel expects with log statements

The expects weren't problematic and had nicer code. They just clutter test
output.

* Remove the old wallet file

It predates the coordinator design and shouldn't be used.

* Rename tests/scan.rs to tests/scanner.rs

* Add a wallet test

Complements the recently removed wallet file by adding a test for the scanner,
scheduler, and signer together.

* Work on a run function

Triggers a clippy ICE.

* Resolve clippy ICE

The issue was the non-fully specified lambda in signer.

* Add KeyGenEvent and KeyGenOrder

Needed so we get KeyConfirmed messages from the key gen task.

While we could've read the CoordinatorMessage to see that, routing through the
key gen tasks ensures we only handle it once it's been successfully saved to
disk.

* Expand scanner test

* Clarify processor documentation

* Have the Scanner load keys on boot/save outputs to disk

* Use Vec<u8> for Block ID

Much more flexible.

* Panic if we see the same output multiple times

* Have the Scanner DB mark itself as corrupt when doing a multi-put

This REALLY should be a TX. Since we don't have a TX API right now, this at
least offers detection.

* Have DST'd DB keys accept AsRef<[u8]>

* Restore polling all signers

Writes a custom future to do so.

Also loads signers on boot using what the scanner claims are active keys.

* Schedule OutInstructions

Adds a data field to Payment.

Also cleans some dead code.

* Panic if we create an invalid transaction

Saves the TX once it's successfully signed so if we do panic, we have a copy.

* Route coordinator messages to their respective signer

Requires adding key to the SignId.

* Send SignTransaction orders for all plans

* Add a timer to retry sign_plans when prepare_send fails

* Minor fmt'ing

* Basic Fee API

* Move the change key into Plan

* Properly route activation_number

* Remove ScannerEvent::Block

It's not used under current designs

* Nicen logs

* Add utilities to get a block's number

* Have main issue AckBlock

Also has a few misc lints.

* Parse instructions out of outputs

* Tweak TODOs and remove an unwrap

* Update Bitcoin max input/output quantity

* Only read one piece of data from Monero

Due to output randomization, it's infeasible.

* Embed plan IDs into the TXs they create

We need to stop attempting signing if we've already signed a protocol. Ideally,
any one of the participating signers should be able to provide a proof the TX
was successfully signed. We can't just run a second signing protocol though as
a single malicious signer could complete the TX signature, and publish it,
yet not complete the secondary signature.

The TX itself has to be sufficient to show that the TX matches the plan. This
is done by embedding the ID, so matching addresses/amounts plans are
distinguished, and by allowing verification a TX actually matches a set of
addresses/amounts.

For Monero, this will need augmenting with the ephemeral keys (or usage of a
static seed for them).

* Don't use OP_RETURN to encode the plan ID on Bitcoin

We can use the inputs to distinguih identical-output plans without issue.

* Update OP_RETURN data access

It's not required to be the last output.

* Add Eventualities to Monero

An Eventuality is an effective equivalent to a SignableTransaction. That is
declared not by the inputs it spends, yet the outputs it creates.
Eventualities are also bound to a 32-byte RNG seed, enabling usage of a
hash-based identifier in a SignableTransaction, allowing multiple
SignableTransactions with the same output set to have different Eventualities.

In order to prevent triggering the burning bug, the RNG seed is hashed with
the planned-to-be-used inputs' output keys. While this does bind to them, it's
only loosely bound. The TX actually created may use different inputs entirely
if a forgery is crafted (which requires no brute forcing).

Binding to the key images would provide a strong binding, yet would require
knowing the key images, which requires active communication with the spend
key.

The purpose of this is so a multisig can identify if a Transaction the entire
group planned has been executed by a subset of the group or not. Once a plan
is created, it can have an Eventuality made. The Eventuality's extra is able
to be inserted into a HashMap, so all new on-chain transactions can be
trivially checked as potential candidates. Once a potential candidate is found,
a check involving ECC ops can be performed.

While this is arguably a DoS vector, the underlying Monero blockchain would
need to be spammed with transactions to trigger it. Accordingly, it becomes
a Monero blockchain DoS vector, when this code is written on the premise
of the Monero blockchain functioning. Accordingly, it is considered handled.

If a forgery does match, it must have created the exact same outputs the
multisig would've. Accordingly, it's argued the multisig shouldn't mind.

This entire suite of code is only necessary due to the lack of outgoing
view keys, yet it's able to avoid an interactive protocol to communicate
key images on every single received output.

While this could be locked to the multisig feature, there's no practical
benefit to doing so.

* Add support for encoding Monero address to instructions

* Move Serai's Monero address encoding into serai-client

serai-client is meant to be a single library enabling using Serai. While it was
originally written as an RPC client for Serai, apps actually using Serai will
primarily be sending transactions on connected networks. Sending those
transactions require proper {In, Out}Instructions, including proper address
encoding.

Not only has address encoding been moved, yet the subxt client is now behind
a feature. coin integrations have their own features, which are on by default.
primitives are always exposed.

* Reorganize file layout a bit, add feature flags to processor

* Tidy up ETH Dockerfile

* Add Bitcoin address encoding

* Move Bitcoin::Address to serai-client's

* Comment where tweaking needs to happen

* Add an API to check if a plan was completed in a specific TX

This allows any participating signer to submit the TX ID to prevent further
signing attempts.

Also performs some API cleanup.

* Minimize FROST dependencies

* Use a seeded RNG for key gen

* Tweak keys from Key gen

* Test proper usage of Branch/Change addresses

Adds a more descriptive error to an error case in decoys, and pads Monero
payments as needed.

* Also test spending the change output

* Add queued_plans to the Scheduler

queued_plans is for payments to be issued when an amount appears, yet the
amount is currently pre-fee. One the output is actually created, the
Scheduler should be notified of the amount it was created with, moving from
queued_plans to plans under the actual amount.

Also tightens debug_asserts to asserts for invariants which may are at risk of
being exclusive to prod.

* Add missing tweak_keys call

* Correct decoy selection height handling

* Add a few log statements to the scheduler

* Simplify test's get_block_number

* Simplify, while making more robust, branch address handling in Scheduler

* Have fees deducted from payments

Corrects Monero's handling of fees when there's no change address.

Adds a DUST variable, as needed due to 1_00_000_000 not being enough to pay
its fee on Monero.

* Add comment to Monero

* Consolidate BTC/XMR prepare_send code

These aren't fully consolidated. We'd need a SignableTransaction trait for
that. This is a lot cleaner though.

* Ban integrated addresses

The reasoning why is accordingly documented.

* Tidy TODOs/dust handling

* Update README TODO

* Use a determinisitic protocol version in Monero

* Test rebuilt KeyGen machines function as expected

* Use a more robust KeyGen entropy system

* Add DB TXNs

Also load entropy from env

* Add a loop for processing messages from substrate

Allows detecting if we're behind, and if so, waiting to handle the message

* Set Monero MAX_INPUTS properly

The previous number was based on an old hard fork. With the ring size having
increased, transactions have since got larger.

* Distinguish TODOs into TODO and TODO2s

TODO2s are for after protonet

* Zeroize secret share repr in ThresholdCore write

* Work on Eventualities

Adds serialization and stops signing when an eventuality is proven.

* Use a more robust DB key schema

* Update to {k, p}256 0.12

* cargo +nightly clippy

* cargo update

* Slight message-box tweaks

* Update to recent Monero merge

* Add a Coordinator trait for communication with coordinator

* Remove KeyGenHandle for just KeyGen

While KeyGen previously accepted instructions over a channel, this breaks the
ack flow needed for coordinator communication. Now, KeyGen is the direct object
with a handle() function for messages.

Thankfully, this ended up being rather trivial for KeyGen as it has no
background tasks.

* Add a handle function to Signer

Enables determining when it's finished handling a CoordinatorMessage and
therefore creating an acknowledgement.

* Save transactions used to complete eventualities

* Use a more intelligent sleep in the signer

* Emit SignedTransaction with the first ID *we can still get from our node*

* Move Substrate message handling into the new coordinator recv loop

* Add handle function to Scanner

* Remove the plans timer

Enables ensuring the ordring on the handling of plans.

* Remove the outputs function which panicked if a precondition wasn't met

The new API only returns outputs upon satisfaction of the precondition.

* Convert SignerOrder::SignTransaction to a function

* Remove the key_gen object from sign_plans

* Refactor out get_fee/prepare_send into dedicated functions

* Save plans being signed to the DB

* Reload transactions being signed on boot

* Stop reloading TXs being signed (and report it to peers)

* Remove message-box from the processor branch

We don't use it here yet.

* cargo +nightly fmt

* Move back common/zalloc

* Update subxt to 0.27

* Zeroize ^1.5, not 1

* Update GitHub workflow

* Remove usage of SignId in completed
2023-03-16 22:59:40 -04:00