nim-dagger/codex/slots/builder/builder.nim

389 lines
11 KiB
Nim

## Nim-Codex
## Copyright (c) 2023 Status Research & Development GmbH
## Licensed under either of
## * Apache License, version 2.0, ([LICENSE-APACHE](LICENSE-APACHE))
## * MIT license ([LICENSE-MIT](LICENSE-MIT))
## at your option.
## This file may not be copied, modified, or distributed except according to
## those terms.
{.push raises: [].}
import std/math
import std/sequtils
import std/sugar
import pkg/libp2p
import pkg/chronos
import pkg/questionable
import pkg/questionable/results
import pkg/poseidon2
import pkg/poseidon2/io
import pkg/constantine/math/arithmetic/finite_fields
import ../../logutils
import ../../indexingstrategy
import ../../merkletree
import ../../stores
import ../../manifest
import ../../utils
import ../../utils/asynciter
import ../../utils/digest
import ../../utils/poseidon2digest
import ../converters
export converters
logScope:
topics = "codex slotsbuilder"
const
# TODO: Unified with the DefaultCellSize specified in branch "data-sampler"
# in the proving circuit.
DefaultEmptyBlock* = newSeq[byte](DefaultBlockSize.int)
DefaultEmptyCell* = newSeq[byte](DefaultCellSize.int)
type
# TODO: should be a generic type that
# supports all merkle trees
SlotsBuilder* = ref object of RootObj
store: BlockStore
manifest: Manifest
strategy: IndexingStrategy
cellSize: NBytes
emptyDigestTree: Poseidon2Tree
blockPadBytes: seq[byte]
slotsPadLeafs: seq[Poseidon2Hash]
rootsPadLeafs: seq[Poseidon2Hash]
slotRoots: seq[Poseidon2Hash]
verifyTree: ?Poseidon2Tree
func slotRoots*(self: SlotsBuilder): seq[Poseidon2Hash] {.inline.} =
## Returns the slot roots.
##
self.slotRoots
func verifyTree*(self: SlotsBuilder): ?Poseidon2Tree {.inline.} =
## Returns the slots tree (verification tree).
##
self.verifyTree
func verifyRoot*(self: SlotsBuilder): ?Poseidon2Hash {.inline.} =
## Returns the slots root (verification root).
##
self.verifyTree.?root().?toOption
func nextPowerOfTwoPad*(a: int): int =
## Returns the difference between the original
## value and the next power of two.
##
nextPowerOfTwo(a) - a
func numBlockPadBytes*(self: SlotsBuilder): Natural =
## Number of padding bytes required for a pow2
## merkle tree for each block.
##
self.blockPadBytes.len
func numSlotsPadLeafs*(self: SlotsBuilder): Natural =
## Number of padding field elements required for a pow2
## merkle tree for each slot.
##
self.slotsPadLeafs.len
func numRootsPadLeafs*(self: SlotsBuilder): Natural =
## Number of padding field elements required for a pow2
## merkle tree for the slot roots.
##
self.rootsPadLeafs.len
func numSlots*(self: SlotsBuilder): Natural =
## Number of slots.
##
self.manifest.numSlots
func numSlotBlocks*(self: SlotsBuilder): Natural =
## Number of blocks per slot.
##
self.manifest.blocksCount div self.manifest.numSlots
func slotBytes*(self: SlotsBuilder): NBytes =
## Number of bytes per slot.
##
(self.manifest.blockSize.int * self.numSlotBlocks).NBytes
func numBlockCells*(self: SlotsBuilder): Natural =
## Number of cells per block.
##
(self.manifest.blockSize div self.cellSize).Natural
func numBlockCellsPadded*(self: SlotsBuilder): Natural =
## Number of cells per block including padding.
##
nextPowerOfTwo(self.numBlockCells.int).Natural
func cellSize*(self: SlotsBuilder): NBytes =
## Cell size.
##
self.cellSize
func numSlotCells*(self: SlotsBuilder): Natural =
## Number of cells per slot.
##
self.numBlockCells * self.numSlotBlocks
func numSlotCellsPadded*(self: SlotsBuilder): Natural =
## Number of cells per slot including padding.
##
nextPowerOfTwo(self.numBlockCellsPadded.int * self.numSlotBlocks.int).Natural
func emptyDigestTree*(self: SlotsBuilder): Poseidon2Tree {.inline.} =
## Returns the tree of a padding block.
##
self.emptyDigestTree
func slotIndiciesIter*(self: SlotsBuilder, slot: Natural): ?!Iter[int] =
## Returns the slot indices.
##
self.strategy.getIndicies(slot).catch
func slotIndicies*(self: SlotsBuilder, slot: Natural): seq[int] =
## Returns the slot indices.
##
if iter =? self.strategy.getIndicies(slot).catch:
toSeq(iter)
else:
trace "Failed to get slot indicies"
newSeq[int]()
func manifest*(self: SlotsBuilder): Manifest =
## Returns the manifest.
##
self.manifest
proc buildBlockTree*(
self: SlotsBuilder,
blkIdx: Natural): Future[?!(seq[byte], Poseidon2Tree)] {.async.} =
without blk =? await self.store.getBlock(self.manifest.treeCid, blkIdx), err:
error "Failed to get block CID for tree at index"
return failure(err)
if blk.isEmpty:
success (DefaultEmptyBlock & self.blockPadBytes, self.emptyDigestTree)
else:
without tree =?
Poseidon2Tree.digestTree(blk.data & self.blockPadBytes, self.cellSize.int), err:
error "Failed to create digest for block"
return failure(err)
success (blk.data, tree)
proc getBlockHashes*(
self: SlotsBuilder,
slotIndex: Natural): Future[?!seq[Poseidon2Hash]] {.async.} =
let
treeCid = self.manifest.treeCid
blockCount = self.manifest.blocksCount
numberOfSlots = self.manifest.numSlots
logScope:
treeCid = treeCid
blockCount = blockCount
numberOfSlots = numberOfSlots
index = blkIdx
slotIndex = slotIndex
let
hashes: seq[Poseidon2Hash] = collect(newSeq):
for blkIdx in self.strategy.getIndicies(slotIndex):
trace "Getting block CID for tree at index"
without (_, blockTree) =? (await self.buildBlockTree(blkIdx)) and
digest =? blockTree.root, err:
error "Failed to get block CID for block tree at index", err = err.msg
return failure(err)
digest
success hashes
proc buildSlotTree*(
self: SlotsBuilder,
slotIndex: Natural): Future[?!Poseidon2Tree] {.async.} =
without blockHashes =? (await self.getBlockHashes(slotIndex)), err:
error "Failed to select slot blocks", err = err.msg
return failure(err)
Poseidon2Tree.init(blockHashes & self.slotsPadLeafs)
proc buildSlot*(
self: SlotsBuilder,
slotIndex: Natural): Future[?!Poseidon2Hash] {.async.} =
## Build a slot tree and store it in the block store.
##
logScope:
cid = self.manifest.treeCid
slotIndex = slotIndex
trace "Building slot tree"
without tree =? (await self.buildSlotTree(slotIndex)) and
treeCid =? tree.root.?toSlotCid, err:
error "Failed to build slot tree", err = err.msg
return failure(err)
trace "Storing slot tree", treeCid, slotIndex, leaves = tree.leavesCount
for i, leaf in tree.leaves:
without cellCid =? leaf.toCellCid, err:
error "Failed to get CID for slot cell", err = err.msg
return failure(err)
without proof =? tree.getProof(i) and
encodableProof =? proof.toEncodableProof, err:
error "Failed to get proof for slot tree", err = err.msg
return failure(err)
if err =? (await self.store.putCidAndProof(
treeCid, i, cellCid, encodableProof)).errorOption:
error "Failed to store slot tree", err = err.msg
return failure(err)
tree.root()
func buildVerifyTree*(
self: SlotsBuilder,
slotRoots: openArray[Poseidon2Hash]): ?!Poseidon2Tree =
Poseidon2Tree.init(@slotRoots & self.rootsPadLeafs)
proc buildSlots*(self: SlotsBuilder): Future[?!void] {.async.} =
## Build all slot trees and store them in the block store.
##
logScope:
cid = self.manifest.treeCid
blockCount = self.manifest.blocksCount
trace "Building slots"
if self.slotRoots.len == 0:
self.slotRoots = collect(newSeq):
for i in 0..<self.manifest.numSlots:
without slotRoot =? (await self.buildSlot(i)), err:
error "Failed to build slot", err = err.msg, index = i
return failure(err)
slotRoot
without tree =? self.buildVerifyTree(self.slotRoots) and root =? tree.root, err:
error "Failed to build slot roots tree", err = err.msg
return failure(err)
if verifyTree =? self.verifyTree and verifyRoot =? verifyTree.root:
if verifyRoot != root: # TODO: `!=` doesn't work for SecretBool
return failure "Existing slots root doesn't match reconstructed root."
self.verifyTree = some tree
success()
proc buildManifest*(self: SlotsBuilder): Future[?!Manifest] {.async.} =
if err =? (await self.buildSlots()).errorOption:
error "Failed to build slot roots", err = err.msg
return failure(err)
without rootCids =? self.slotRoots.toSlotCids(), err:
error "Failed to map slot roots to CIDs", err = err.msg
return failure(err)
without rootProvingCidRes =? self.verifyRoot.?toVerifyCid() and
rootProvingCid =? rootProvingCidRes, err: # TODO: why doesn't `.?` unpack the result?
error "Failed to map slot roots to CIDs", err = err.msg
return failure(err)
Manifest.new(self.manifest, rootProvingCid, rootCids)
proc new*(
T: type SlotsBuilder,
store: BlockStore,
manifest: Manifest,
strategy: ?IndexingStrategy = none IndexingStrategy,
cellSize = DefaultCellSize): ?!SlotsBuilder =
if not manifest.protected:
return failure("Can only create SlotsBuilder using protected manifests.")
if (manifest.blocksCount mod manifest.numSlots) != 0:
return failure("Number of blocks must be divisable by number of slots.")
if (manifest.blockSize mod cellSize) != 0.NBytes:
return failure("Block size must be divisable by cell size.")
let
strategy = if strategy.isNone:
? SteppedIndexingStrategy.new(
0, manifest.blocksCount - 1, manifest.numSlots).catch
else:
strategy.get
# all trees have to be padded to power of two
numBlockCells = (manifest.blockSize div cellSize).int # number of cells per block
blockPadBytes = newSeq[byte](numBlockCells.nextPowerOfTwoPad * cellSize.int) # power of two padding for blocks
numSlotBlocks = (manifest.blocksCount div manifest.numSlots)
slotsPadLeafs = newSeqWith(numSlotBlocks.nextPowerOfTwoPad, Poseidon2Zero) # power of two padding for block roots
rootsPadLeafs = newSeqWith(manifest.numSlots.nextPowerOfTwoPad, Poseidon2Zero)
emptyDigestTree = ? Poseidon2Tree.digestTree(DefaultEmptyBlock & blockPadBytes, DefaultCellSize.int)
var self = SlotsBuilder(
store: store,
manifest: manifest,
strategy: strategy,
cellSize: cellSize,
blockPadBytes: blockPadBytes,
slotsPadLeafs: slotsPadLeafs,
rootsPadLeafs: rootsPadLeafs,
emptyDigestTree: emptyDigestTree)
if manifest.verifiable:
if manifest.slotRoots.len == 0 or manifest.slotRoots.len != manifest.numSlots:
return failure "Manifest is verifiable but slot roots are missing or invalid."
let slotRoots = manifest.slotRoots.mapIt( (? it.fromSlotCid()))
without tree =? self.buildVerifyTree(slotRoots), err:
error "Failed to build slot roots tree", err = err.msg
return failure(err)
without expectedRoot =? manifest.verifyRoot.fromVerifyCid(), err:
error "Unable to convert manifest verifyRoot to hash", error = err.msg
return failure(err)
if verifyRoot =? tree.root:
if verifyRoot != expectedRoot:
return failure "Existing slots root doesn't match reconstructed root."
self.slotRoots = slotRoots
self.verifyTree = some tree
success self