nimbus-eth2/beacon_chain/eth1/merkle_minimal.nim
Jacek Sieka a7a65bce42
disentangle eth2 types from the ssz library (#2785)
* reorganize ssz dependencies

This PR continues the work in
https://github.com/status-im/nimbus-eth2/pull/2646,
https://github.com/status-im/nimbus-eth2/pull/2779 as well as past
issues with serialization and type, to disentangle SSZ from eth2 and at
the same time simplify imports and exports with a structured approach.

The principal idea here is that when a library wants to introduce SSZ
support, they do so via 3 files:

* `ssz_codecs` which imports and reexports `codecs` - this covers the
basic byte conversions and ensures no overloads get lost
* `xxx_merkleization` imports and exports `merkleization` to specialize
and get access to `hash_tree_root` and friends
* `xxx_ssz_serialization` imports and exports `ssz_serialization` to
specialize ssz for a specific library

Those that need to interact with SSZ always import the `xxx_` versions
of the modules and never `ssz` itself so as to keep imports simple and
safe.

This is similar to how the REST / JSON-RPC serializers are structured in
that someone wanting to serialize spec types to REST-JSON will import
`eth2_rest_serialization` and nothing else.

* split up ssz into a core library that is independendent of eth2 types
* rename `bytes_reader` to `codec` to highlight that it contains coding
and decoding of bytes and native ssz types
* remove tricky List init overload that causes compile issues
* get rid of top-level ssz import
* reenable merkleization tests
* move some "standard" json serializers to spec
* remove `ValidatorIndex` serialization for now
* remove test_ssz_merkleization
* add tests for over/underlong byte sequences
* fix broken seq[byte] test - seq[byte] is not an SSZ type

There are a few things this PR doesn't solve:

* like #2646 this PR is weak on how to handle root and other
dontSerialize fields that "sometimes" should be computed - the same
problem appears in REST / JSON-RPC etc

* Fix a build problem on macOS

* Another way to fix the macOS builds

Co-authored-by: Zahary Karadjov <zahary@gmail.com>
2021-08-18 20:57:58 +02:00

43 lines
1.6 KiB
Nim

# beacon_chain
# Copyright (c) 2018-2021 Status Research & Development GmbH
# Licensed and distributed under either of
# * MIT license (license terms in the root directory or at https://opensource.org/licenses/MIT).
# * Apache v2 license (license terms in the root directory or at https://www.apache.org/licenses/LICENSE-2.0).
# at your option. This file may not be copied, modified, or distributed except according to those terms.
{.push raises: [Defect].}
# https://github.com/ethereum/eth2.0-specs/blob/v1.0.1/tests/core/pyspec/eth2spec/utils/merkle_minimal.py
# Merkle tree helpers
# ---------------------------------------------------------------
import
sequtils,
stew/endians2,
# Specs
../spec/[eth2_merkleization, digest],
../spec/datatypes/base
const depositContractLimit* = Limit(1'u64 shl DEPOSIT_CONTRACT_TREE_DEPTH)
func attachMerkleProofs*(deposits: var openArray[Deposit]) =
let depositsRoots = mapIt(deposits, hash_tree_root(it.data))
var incrementalMerkleProofs = createMerkleizer(depositContractLimit)
for i in 0 ..< depositsRoots.len:
incrementalMerkleProofs.addChunkAndGenMerkleProof(depositsRoots[i], deposits[i].proof)
deposits[i].proof[32] = default(Eth2Digest)
deposits[i].proof[32].data[0..7] = toBytesLE uint64(i + 1)
template getProof*(proofs: seq[Eth2Digest], idxParam: int): openArray[Eth2Digest] =
let
idx = idxParam
## TODO: It's surprising that we have to do +1 here.
## It seems that `depositContractLimit` is set too high.
startIdx = idx * (DEPOSIT_CONTRACT_TREE_DEPTH + 1)
endIdx = startIdx + DEPOSIT_CONTRACT_TREE_DEPTH - 1
proofs.toOpenArray(startIdx, endIdx)