* Security: panic if an internally generated time is out of range
If Zebra has a bug where it generates blocks, transactions, or meta
addresses with bad times, panic. This avoids sending bad data onto the
network.
(Previously, Zebra would truncate some of these times, silently
corrupting the underlying data.)
Make it clear that deserialization of these objects is infalliable.
We modeled a Bitcoin `headers` message as being a list of block headers.
However, the actual data structure is slightly different: it's a list of (block
header, transaction count) pairs. This caused zcashd to reject our headers
messages.
To fix this, introduce a new `CountedHeader` struct with a `block::Header` and
transaction count `usize`, then thread it through the inbound service and the
state.
I tested this locally by running Zebra with these changes and inspecting a
trace-level log of the span of a peer connection that requested a nontrivial
headers packet from us, and verified that it did not reject our message.
This is the first in a sequence of changes that change the block:: items
to not include Block as a prefix in their name, in accordance with the
Rust API guidelines.
This Merkle tree is the SHA256d one used only for including transactions
in a block, so it should be kept there in order to not be confused with
other Merkle trees (like the note commitment trees).
It's not accurate to call it a LightClientRootHash, because it's not
always a root has for a light client -- sometimes it's a different kind
of root hash.
This extracts the `difficulty` module from `block` and the
`equihash_solution` module from the crate root. The PoW calculations
are significantly more complicated than the other block code and pretty
dissimilar from it, so it makes more sense to create a common proof of
work module.
The `EquihashSolution` and `EQUIHASH_SOLUTION_SIZE` are renamed to
`equihash::Solution` and `equihash::SOLUTION_SIZE` and imported that
way, except in `block/header.rs`, to avoid a conflict with the
`equihash` crate. In the future it would be better to encapsulate the
equihash solution check into the `equihash::Solution` type so that
callers only need to import our `work::equihash`.
The test organization leaves a little to be desired but I think that
this can be improved as we fill out the proof of work implementation.
This changes the `light_client_root_hash` field to `light_client_root_bytes` to
hint that it's unparsed, and makes it public to match the rest of the
`BlockHeader` fields. The `LightClientRootHash` serialization methods are
hidden from the public API, so that the `LightClientRootHash` has to be
constructed by the method on the `Block`.
The Heartwood upgrade changes the meaning of the hashFinalSaplingRoot to
hashLightClientRoot. Since we don't know the network upgrade heights in
zebra-chain, we just use [u8; 32] for now.
* create hash submodule for block
* create header submodule for block
* create serialize submodule for block
* add newline to hash.rs (fmt)
* Update zebra-chain/src/block/tests.rs
Co-authored-by: Jane Lusby <jlusby42@gmail.com>
Co-authored-by: Henry de Valence <hdevalence@hdevalence.ca>
Co-authored-by: Jane Lusby <jlusby42@gmail.com>