ShieldedData objects must have at least one spend or output; using Either
ensures that at least one must be present. This is similar to the
JoinSplitData case, but slightly more complicated: rather than enforcing that
one list has at least one element (which can be done as `(first, rest)`), here
we need to use Either. This has the downside that it is possible to construct
multiple equivalent internal representations (choosing whether a spend or
output goes in the `first` slot), but this easily fixed with a custom PartialEq
implementation.
This replaces the read_list function and makes the code significantly cleaner.
The only downside is that it loses exact preallocation, but this is probably not a big deal.
In the previous transaction modeling I defined the structs so that the number
of old and new commitments for a JoinSplit were variable, when in fact the
Sprout design fixes both to be 2. So now they are hardcoded as 2 in the source
code as well. This commit also fixes some missing `pub` fields on the
`JoinSplit` struct.
* Added a few more top-level fields for the Transaction struct
* Add a placeholder Script type.
This could alternately use bytes::Bytes to save some allocations
but I don't think this is important to get perfectly now. In the future, we
will want to have all of the script handling code in the zebra-script crate,
but we will need to have a container type for an encoded script in zebra-chain,
because otherwise zebra-chain would depend on zebra-script and not the other
way around.
* Rename Transaction{Input,Output} -> Transparent{Input,Output}.
These are only *transparent* inputs and outputs, so by putting Transparent in
the name (instead of Transaction) it's more clear that a transaction's inputs
or outputs can also be shielded.
* Add a LockTime enum.
* First attempt at a Transaction enum.
This attempts to map the versioning and field presence rules into an ADT, so
that structurally invalid transactions (e.g., a BCTV14 proof in a Sapling
transaction) are unrepresentable.
* Update zebra-chain/src/transaction.rs
Co-Authored-By: Daira Hopwood <daira@jacaranda.org>
* Add fixme note on type refinement.
* Rename Transaction variants according to version.
* Split transaction.rs into submodules.
* Start filling in spend, output descriptions.
* Progress on JoinSplit data structures.
This has a lot of duplication and should really use generics to abstract over
Sprout-on-BCTV14 or Sprout-on-Groth16.
* Add data types for Bctv14 and Groth16 proofs.
This also adds a trait to abstract over them.
* Make JoinSplit descriptions generic over the proof system.
* Update zebra-chain/src/transaction/joinsplit.rs
Failure uses a distinct Fail trait rather than the standard library's
Error trait, which causes a lot of interoperability problems with tower
and other Error-using crates. Since failure was created, the standard
library's Error trait was improved, and its conveniences are now
available without the custom Fail trait using `thiserror` (for easy
error derives) and `anyhow` (for a better boxed Error).
* Fix authorship, license information.
I *thought* I had done a sed pass over the Cargo defaults when doing
repository initialization, but I guess I missed it or something.
Anyways, fixed now.
This removes the inventory vector structs from `zebra-chain` (as they
are really part of the network protocol) and refactors them into a
single `InventoryHash` type. This corresponds to Bitcoin's "inventory
vector" but with a different, better name (it's not a vector, it's just
a typed hash of some other item).
This adds convenience methods to `ReadZcashExt` that read 4 and 12 byte
fixed size arrays from the `Reader`, making the actual parsing code more
legible.
Closes#10.
The core serialization logic is now in zebra-chain and consists of two
pairs of traits:
These are analogues of the Serde `Serialize` and `Deserialize` traits,
but explicitly intended for consensus-critical serialization formats.
Thus some struct `Foo` may have derived `Serialize` and `Deserialize`
implementations for (internal) use with Serde, and explicitly-written
`ZcashSerialize` and `ZcashDeserialize` implementations for use in
consensus-critical contexts. The consensus-critical implementations
provide `zcash`-prefixed `zcash_serialize` and `zcash_deserialize`
methods to make it clear in client contexts that the serialization is
consensus-critical.
These are utility traits, analogous to the `ReadBytesExt` and
`WriteBytesExt` traits provided by `byteorder`. A generic
implementation is provided for any `io::Read` or `io::Write`, so that
bringing the traits into scope adds additional Zcash-specific traits to
generic readers and writers -- for instance, writing a `u64` in the
Bitcoin "CompactSize" format.
Deirdre Connolly
dependabot-preview[bot]
Henry de Valence