nimbus-eth1/stateless/witness_from_tree.nim

269 lines
8.3 KiB
Nim

import
stew/[byteutils, endians2],
nimcrypto/[keccak, hash], eth/rlp,
eth/trie/[trie_defs, nibbles, db],
faststreams/output_stream,
./witness_types
type
DB = TrieDatabaseRef
WitnessBuilder* = object
db*: DB
root: KeccakHash
output: OutputStream
proc initWitnessBuilder*(db: DB, rootHash: KeccakHash = emptyRlpHash): WitnessBuilder =
result.db = db
result.root = rootHash
result.output = memoryOutput().s
template extensionNodeKey(r: Rlp): auto =
hexPrefixDecode r.listElem(0).toBytes
proc expectHash(r: Rlp): seq[byte] =
result = r.toBytes
if result.len != 32:
raise newException(RlpTypeMismatch,
"RLP expected to be a Keccak hash value, but has an incorrect length")
template getNode(elem: untyped): untyped =
if elem.isList: @(elem.rawData)
else: get(wb.db, elem.expectHash)
proc rlpListToBitmask(r: var Rlp): uint =
var i = 0
for branch in r:
if not branch.isEmpty:
result.setBranchMaskBit(i)
inc i
r.position = 0
proc writeU32(wb: var WitnessBuilder, x: uint32) =
wb.output.append(toBytesBE(x))
proc writeNibbles(wb: var WitnessBuilder; n: NibblesSeq) =
let nibblesLen = n.len
let numBytes = nibblesLen div 2 + nibblesLen mod 2
var bytes: array[32, byte]
doAssert(nibblesLen >= 1)
doAssert(numBytes >= 0 and numBytes <= 64)
for pos in 0..<n.len:
if (pos and 1) != 0:
bytes[pos div 2] = bytes[pos div 2] or n[pos]
else:
bytes[pos div 2] = bytes[pos div 2] or (n[pos] shl 4)
# write nibblesLen
wb.output.append(nibblesLen.byte)
# write nibbles
wb.output.append(bytes.toOpenArray(0, numBytes-1))
proc writeExtensionNode(wb: var WitnessBuilder, n: NibblesSeq, depth: int, node: openArray[byte]) =
# write type
wb.output.append(ExtensionNodeType.byte)
# write nibbles
wb.writeNibbles(n)
when defined(debugDepth):
wb.output.append(depth.byte)
when defined(debugHash):
wb.output.append(keccak(node).data)
proc writeBranchNode(wb: var WitnessBuilder, mask: uint, depth: int, node: openArray[byte]) =
# write type
# branch node 17th elem should always empty
doAssert mask.branchMaskBitIsSet(16) == false
wb.output.append(BranchNodeType.byte)
# write branch mask
wb.output.append(((mask shr 8) and 0xFF).byte)
wb.output.append((mask and 0xFF).byte)
when defined(debugDepth):
wb.output.append(depth.byte)
when defined(debugHash):
wb.output.append(keccak(node).data)
proc writeAccountNode(wb: var WitnessBuilder, node: openArray[byte], depth: int) =
# write type
wb.output.append(AccountNodeType.byte)
wb.writeU32(node.len.uint32)
wb.output.append(node)
when defined(debugDepth):
wb.output.append(depth.byte)
proc writeHashNode(wb: var WitnessBuilder, node: openArray[byte]) =
# write type
wb.output.append(HashNodeType.byte)
wb.output.append(node)
proc writeShortNode(wb: var WitnessBuilder, node: openArray[byte], depth: int) =
var nodeRlp = rlpFromBytes node
if not nodeRlp.hasData or nodeRlp.isEmpty: return
case nodeRlp.listLen
of 2:
let (isLeaf, k) = nodeRlp.extensionNodeKey
if isLeaf:
writeAccountNode(wb, node, depth)
else:
writeExtensionNode(wb, k, depth, node)
of 17:
let branchMask = rlpListToBitmask(nodeRlp)
writeBranchNode(wb, branchMask, depth, node)
for i in 0..<16:
if branchMask.branchMaskBitIsSet(i):
var branch = nodeRlp.listElem(i)
let nextLookup = branch.getNode
writeShortNode(wb, nextLookup, depth + 1)
# 17th elem should always empty
doAssert branchMask.branchMaskBitIsSet(16) == false
else:
raise newException(CorruptedTrieDatabase, "Bad Short Node")
proc getBranchRecurseAux(wb: var WitnessBuilder, node: openArray[byte], path: NibblesSeq, depth: int) =
var nodeRlp = rlpFromBytes node
if not nodeRlp.hasData or nodeRlp.isEmpty: return
case nodeRlp.listLen
of 2:
let (isLeaf, k) = nodeRlp.extensionNodeKey
let sharedNibbles = sharedPrefixLen(path, k)
if sharedNibbles == k.len:
let value = nodeRlp.listElem(1)
if not isLeaf:
# ExtensionNodeType
writeExtensionNode(wb, k, depth, node)
let nextLookup = value.getNode
getBranchRecurseAux(wb, nextLookup, path.slice(sharedNibbles), depth + sharedNibbles)
else:
# AccountNodeType
writeAccountNode(wb, node, depth)
else:
writeHashNode(wb, keccak(node).data)
of 17:
let branchMask = rlpListToBitmask(nodeRlp)
writeBranchNode(wb, branchMask, depth, node)
let notLeaf = path.len != 0
for i in 0..<16:
if branchMask.branchMaskBitIsSet(i):
var branch = nodeRlp.listElem(i)
if notLeaf and i == path[0].int:
let nextLookup = branch.getNode
getBranchRecurseAux(wb, nextLookup, path.slice(1), depth + 1)
else:
if branch.isList:
let nextLookup = branch.getNode
writeShortNode(wb, nextLookup, depth + 1)
else:
writeHashNode(wb, branch.expectHash)
# 17th elem should always empty
doAssert branchMask.branchMaskBitIsSet(16) == false
else:
raise newException(CorruptedTrieDatabase,
"HexaryTrie node with an unexpected number of children")
proc getBranchRecurse*(wb: var WitnessBuilder; key: openArray[byte]): seq[byte] =
var node = wb.db.get(wb.root.data)
getBranchRecurseAux(wb, node, initNibbleRange(key), 0)
result = wb.output.getOutput(seq[byte])
proc getBranchStack*(wb: WitnessBuilder; key: openArray[byte]): string =
var
node = wb.db.get(wb.root.data)
stack = @[(node, initNibbleRange(key))]
result.add node.toHex
while stack.len > 0:
let (node, path) = stack.pop()
if node.len == 0: continue
var nodeRlp = rlpFromBytes node
case nodeRlp.listLen
of 2:
let (isLeaf, k) = nodeRlp.extensionNodeKey
let sharedNibbles = sharedPrefixLen(path, k)
if sharedNibbles == k.len:
let value = nodeRlp.listElem(1)
if not isLeaf:
let nextLookup = value.getNode
stack.add((nextLookup, path.slice(sharedNibbles)))
result.add nextLookup.toHex
of 17:
if path.len != 0:
var branch = nodeRlp.listElem(path[0].int)
if not branch.isEmpty:
let nextLookup = branch.getNode
stack.add((nextLookup, path.slice(1)))
result.add nextLookup.toHex
else:
raise newException(CorruptedTrieDatabase,
"HexaryTrie node with an unexpected number of children")
proc getBranch*(wb: WitnessBuilder; key: openArray[byte]): seq[seq[byte]] =
var
node = wb.db.get(wb.root.data)
stack = @[(node, initNibbleRange(key))]
result.add node
while stack.len > 0:
let (node, path) = stack.pop()
if node.len == 0: continue
var nodeRlp = rlpFromBytes node
case nodeRlp.listLen
of 2:
let (isLeaf, k) = nodeRlp.extensionNodeKey
let sharedNibbles = sharedPrefixLen(path, k)
if sharedNibbles == k.len:
let value = nodeRlp.listElem(1)
if not isLeaf:
let nextLookup = value.getNode
stack.add((nextLookup, path.slice(sharedNibbles)))
result.add nextLookup
of 17:
if path.len != 0:
var branch = nodeRlp.listElem(path[0].int)
if not branch.isEmpty:
let nextLookup = branch.getNode
stack.add((nextLookup, path.slice(1)))
result.add nextLookup
else:
raise newException(CorruptedTrieDatabase,
"HexaryTrie node with an unexpected number of children")
proc buildWitness*(wb: var WitnessBuilder; key: openArray[byte]) =
var
node = wb.db.get(wb.root.data)
stack = @[(node, initNibbleRange(key))]
while stack.len > 0:
let (node, path) = stack.pop()
if node.len == 0: continue
var nodeRlp = rlpFromBytes node
case nodeRlp.listLen
of 2:
let (isLeaf, k) = nodeRlp.extensionNodeKey
let sharedNibbles = sharedPrefixLen(path, k)
if sharedNibbles == k.len:
let value = nodeRlp.listElem(1)
if not isLeaf:
let nextLookup = value.getNode
stack.add((nextLookup, path.slice(sharedNibbles)))
of 17:
if path.len != 0:
var branch = nodeRlp.listElem(path[0].int)
if not branch.isEmpty:
let nextLookup = branch.getNode
stack.add((nextLookup, path.slice(1)))
else:
raise newException(CorruptedTrieDatabase,
"HexaryTrie node with an unexpected number of children")