* Add a `Transaction::version` getter
Returns the version of the transaction as a `u32`.
* Add `Transaction::is_overwintered` helper method
Returns if the `fOverwintered` flag should be set for the transaction's
version.
* Use new helpers to serialize transaction version
Reduce the repeated code and make it less error-prone with future
changes.
* Add getter methods to `transaction::Request` type
Refactor to move the type deconstruction code into the `Request` type.
The main objective is to make it easier to split the call handler into
methods that receive the request directly.
* Refactor to create `verify_v4_transaction` helper
Split the code specific to V4 transactions into a separate helper
method.
* Create `verify_v5_transaction` helper method
Prepare a separate method to have the validation code.
* Add `UnsupportedByNetworkUpgrade` error variant
An error for when a transaction's version isn't supported by the network
upgrade of the block it's included or for the current network upgrade if
the transaction is for the mempool.
* Verify a V5 transaction's network upgrade
For now, only NU5 supports V5 transactions.
* Test that V5 transaction is rejected on Canopy
Create a fake V5 transaction and try to verify it using a block height
from Canopy's activation. The verifier should reject the transaction
with an error saying that the network upgrade does not support that
transaction version.
* Test if V5 tx. is accepted after NU5 activation
Create a fake V5 transaction and pretend it is placed in a block that
has a height after the NU5 activation. The test should succeed, but
since the NU5 activation height has not been specified yet (neither for
the testnet nor the mainnet), for now this test is marked as
`should_panic`.
* Add `TODO` comment to the code
Add more detail to what's left to do, and link to the appropriate PRs.
* Use `u32` to store transaction version
Use a type consistent with how the version is specified.
Co-authored-by: teor <teor@riseup.net>
Co-authored-by: teor <teor@riseup.net>
* Implement `PartialEq<i64>` for `Amount`
Allows to compare an `Amount` instance directly to an integer.
* Add `SerializationError::BadTransactionBalance`
Error variant representing deserialization of a transaction that doesn't
conform to the Sapling consensus rule where the balance MUST be zero if
there aren't any shielded spends and outputs.
* Validate consensus rule when deserializing
Return an error if the deserialized V4 transaction has a non-zero value
balance but doesn't have any Sapling shielded spends nor outputs.
* Add consensus rule link to field documentation
Describe how the consensus rule is validated structurally by
`ShieldedData`.
* Clarify that `value_balance` is zero
Make the description more concise and objective.
Co-authored-by: Alfredo Garcia <oxarbitrage@gmail.com>
* Update field documentation
Include information about how the consensus rule is guaranteed during
serialization.
Co-authored-by: teor <teor@riseup.net>
* Remove `check::sapling_balances_match` function
The check is redundant because the respective consensus rule is
validated structurally by `ShieldedData`.
* Test deserialization of invalid V4 transaction
A transaction with no Sapling shielded spends and no outputs but with a
non-zero balance value should fail to deserialize.
* Change least-significant byte of the value balance
State how the byte index is calculated, and change the least
significant-byte to be non-zero.
Co-authored-by: teor <teor@riseup.net>
* validate sapling v5 tx
* Make itertools dependency optional
We only need itertools when the `proptest-impl` feature is enabled.
* Check if V4 and V5 coinbase transactions contain PrevOut transparent inputs
This is a bugfix on V4 transaction validation. The PrevOut consensus
rule was not explicitly stated in the Zcash spec until April 2021.
(But it was implied by Bitcoin, and partially implemented by Zebra.)
Also do the shielded sapling input check for V5 transactions.
* Add spec and orchard TODOs to has_inputs_and_outputs
Also make the variable names match the spec.
* Sort transaction functions to match v5 data order
* Simplify transaction input and output checks
Move counts or iterators into `Transaction` methods, so we can remove
duplicate code, and make the consensus rule logic clearer.
* Update sapling_balances_match for Transaction v5
- Quote from the spec
- Explain why the function is redunant for v5
- Rename the function so it's clear that it is sapling-specific
Co-authored-by: teor <teor@riseup.net>
* start refactoring transaction v4 for transaction v5
- move ShieldedData to sapling
- add AnchorVariant
- rename shielded_data to sapling_shielded data in V4
- move value_balance into ShieldedData
- update prop tests for new structure
* add AnchorVariant to Spend
- make anchor types available from sapling crate
- update serialize
* change shielded_balances_match() arguments
* change variable name anchor to shared_anchor in ShieldedData
* fix empty value balance serialization
* use AnchorV in shielded spends
* Rename anchor to per_spend_anchor
* Use nullifiers function directly in non-finalized state
* Use self.value_balance instead of passing it as an argument
* Add missing fields to ShieldedData PartialEq
* Derive Copy for tag types
* Add doc comments for ShieldedData refactor
* Implement a per-spend anchor compatibility iterator
Co-authored-by: teor <teor@riseup.net>
* Ed25519 async batch verification for JoinSplit signatures
We've been verifying JoinSplitSigs one-by-one pre-ZIP-215. Now as we're post-ZIP-215,
we can take advantage of the batch math to validate this signatures.
I would have pumped all the joinsplits in our MAINNET_BLOCKS test vectors but these
signatures are over the sighash, which needs the NU code to compute, and once we're
doing all that set up, we're basically doing transaction validation, so.
Resolves#1944
* Repoint to latest ed25519-zebra commit with note to point at 3.0 when released
Co-authored-by: Alfredo Garcia <oxarbitrage@gmail.com>
Co-authored-by: teor <teor@riseup.net>
* add transaction V5 stub
* add v5_strategy
* deduplicate version group ids
* Update comment for V5 transactions
* Add V5 transactions to non_finalized_state
Currently these are all `unimplemented!(...)`
* Fix struct matches
* Apply trivial panic message changes
* add zcash_deserialize for V5
* make all tx versions explicit in sprout and sapling nullifier functions
* match exhaustively in sprout and sapling nullifier functions
* fix matches in zebra-consensus
* fix NU5 strategy
* We're still deciding if v5 transactions support Sprout
Co-authored-by: teor <teor@riseup.net>
This PR is the first step in getting a groth16 proving system fully
integrated with the rest of zebra. This PR implements the initial async
API, but none of the actual batching logic necessary for our eventual
verifier design.
Once the batch verification API from bellman has been implemented we
will need to swap out the "Batch" type defined in this crate with the
new `batch::Verifier` defined in bellman.
* export new precompute api in zebra-script
* remove old API in favor of precompute API
* add multi use test cases and bump version
* update implementation to actually match henry's design
* Add safety comment for zebra-script
Co-authored-by: teor <teor@riseup.net>
This commit changes the state system and database format to track the
provenance of UTXOs, in addition to the outputs themselves.
Specifically, it tracks the following additional metadata:
- the height at which the UTXO was created;
- whether or not the UTXO was created from a coinbase transaction or
not.
This metadata will allow us to:
- check the coinbase maturity consensus rule;
- check the coinbase inputs => no transparent outputs rule;
- implement lookup of transactions by utxo (using the height to find the
block and then scanning the block) for a future RPC mechanism.
Closes#1342
The UTXO query system assumes that a transaction will only request
information about UTXOs created in prior blocks. But transactions are
allowed to spend UTXOs created by prior transactions in the same block.
This doesn't fit with the existing query model, so instead of trying to
change it, allow the script verifier to take an additional set of known
UTXOs, and propagate this set from the block.
This consensus rule is supposed to apply to transactions whose
transparent inputs are the *outputs* of previous coinbase
transactions, not to transactions with coinbase inputs. Because that
logic is different enough from this logic, and requires different data
flow, it's cleaner to just remove this check for now.
Making this check's match statement exhaustive revealed a bug similar to
the previous commit. The logic in the spec is written in terms of
numbers, but our data is internally represented in terms of enums
(ADTs). This kind of cross-representation rule translation is a bug
surface, which we can avoid by converting to counts and summing up. (We
should use one style at a time).
This function caused spurious "WrongVersion" errors, because the match
pattern in the first arm was non-exhaustive, but the fallthrough match
arm was present and assumed it would only be reached if the version was
incorrect.
This commit cleans up the implemenation, splits out the error variants,
and renames the check to be more precise.
To avoid this kind of bug in the future, two guidelines are useful:
1. Avoid fallthrough cases that circumvent non-exhaustive match checks;
2. Avoid nested conditionals, preferring a "straight-line" sequence of
match arm => result pairs rather than nested matches or matches with
conditionals inside.
This squashes the previous sequence of commits to let us separate out
the structural skeleton (which unblocks other work and is not
consensus-critical) from the actual checks (which don't block other work
and are consensus-critical).
Co-authored-by: Deirdre Connolly <deirdre@zfnd.org>
* Flatten consensus::verify::* to consensus::*
* Move consensus::*::tests into their own files
* Move CheckpointList into its own file
* Move Progress and Target into a types module
QueuedBlock and QueuedBlockList can stay in checkpoint.rs, because
they are tightly coupled to CheckpointVerifier.