nimbus-eth1/nimbus/sync/handlers/snap.nim

561 lines
18 KiB
Nim

# Nimbus
# Copyright (c) 2018-2021 Status Research & Development GmbH
# Licensed under either of
# * Apache License, version 2.0, ([LICENSE-APACHE](LICENSE-APACHE) or
# http://www.apache.org/licenses/LICENSE-2.0)
# * MIT license ([LICENSE-MIT](LICENSE-MIT) or
# http://opensource.org/licenses/MIT)
# at your option. This file may not be copied, modified, or distributed
# except according to those terms.
{.push raises: [].}
import
std/sequtils,
chronicles,
chronos,
eth/[common, p2p, trie/db, trie/nibbles],
stew/[byteutils, interval_set],
../../core/chain,
../../db/core_db,
../snap/[constants, range_desc],
../snap/worker/db/[hexary_desc, hexary_error, hexary_paths,
snapdb_persistent, hexary_range],
../protocol,
../protocol/snap/snap_types
logScope:
topics = "snap-wire"
type
SnapWireRef* = ref object of SnapWireBase
chain: ChainRef
elaFetchMax: chronos.Duration
dataSizeMax: int
peerPool: PeerPool
SlotsSpecs = object
slotFn: HexaryGetFn # For accessing storage slots
stoRoot: NodeKey # Storage root
const
extraTraceMessages = false # or true
## Enabled additional logging noise
estimatedNodeSize = hexaryRangeRlpNodesListSizeMax(1)
## Some expected upper limit for a single node
estimatedProofSize = hexaryRangeRlpNodesListSizeMax(10)
## Some expected upper limit, typically not mote than 10 proof nodes
emptySnapStorageList = seq[SnapStorage].default
## Dummy list for empty slots
defaultElaFetchMax = 990.milliseconds
## Fetching accounts or slots can be extensive, stop in the middle if
## it takes too long
defaultDataSizeMax = fetchRequestBytesLimit
## Truncate maximum data size
# ------------------------------------------------------------------------------
# Private functions: helpers
# ------------------------------------------------------------------------------
template logTxt(info: static[string]): static[string] =
"handlers.snap." & info
proc notImplemented(name: string) {.used.} =
debug "Wire handler method not implemented", meth=name
# ----------------------------------
proc getAccountFn(
ctx: SnapWireRef;
): HexaryGetFn
{.gcsafe.} =
# The snap sync implementation provides a function `persistentAccountGetFn()`
# similar to this one. But it is not safe to use it at the moment as the
# storage table might (or might not) differ.
let db = ctx.chain.com.db
return proc(key: openArray[byte]): Blob =
if db.isLegacy:
return db.kvt.backend.toLegacy.get(key)
proc getStoSlotFn(
ctx: SnapWireRef;
accKey: NodeKey;
): HexaryGetFn
{.gcsafe.} =
# The snap sync implementation provides a function
# `persistentStorageSlotsGetFn()` similar to this one. But it is not safe to
# use it at the moment as the storage table might (or might not) differ.
let db = ctx.chain.com.db
return proc(key: openArray[byte]): Blob =
if db.isLegacy:
return db.kvt.backend.toLegacy.get(key)
proc getCodeFn(
ctx: SnapWireRef;
): HexaryGetFn
{.gcsafe.} =
# It is save to borrow this function from the snap sync implementation.
ctx.chain.com.db.persistentContractsGetFn
# ----------------------------------
proc to(
rl: RangeLeaf;
T: type SnapAccount;
): T
{.gcsafe, raises: [RlpError].} =
## Convert the generic `RangeLeaf` argument to payload type.
T(accHash: rl.key.to(Hash256),
accBody: rl.data.decode(Account))
proc to(
rl: RangeLeaf;
T: type SnapStorage;
): T
{.gcsafe.} =
## Convert the generic `RangeLeaf` argument to payload type.
T(slotHash: rl.key.to(Hash256),
slotData: rl.data)
# ------------------------------------------------------------------------------
# Private functions: fetch leaf range
# ------------------------------------------------------------------------------
proc getSlotsSpecs(
ctx: SnapWireRef; # Handler descriptor
rootKey: NodeKey; # State root
accGetFn: HexaryGetFn; # Database abstraction
accKey: NodeKey; # Current account
): Result[SlotsSpecs,void]
{.gcsafe, raises: [CatchableError].} =
## Retrieve storage slots specs from account data
let accData = accKey.hexaryPath(rootKey, accGetFn).leafData
# Ignore missing account entry
if accData.len == 0:
when extraTraceMessages:
trace logTxt "getSlotsSpecs: no such account", accKey, rootKey
return err()
# Ignore empty storage list
let stoRoot = rlp.decode(accData,Account).storageRoot
if stoRoot == EMPTY_ROOT_HASH:
when extraTraceMessages:
trace logTxt "getSlotsSpecs: no slots", accKey
return err()
ok(SlotsSpecs(
slotFn: ctx.getStoSlotFn(accKey),
stoRoot: stoRoot.to(NodeKey)))
iterator doTrieNodeSpecs(
ctx: SnapWireRef; # Handler descriptor
rootKey: NodeKey; # State root
pGroups: openArray[SnapTriePaths]; # Group of partial paths
): (NodeKey, HexaryGetFn, Blob, int)
{.gcsafe, raises: [CatchableError].} =
## Helper for `getTrieNodes()` to cycle over `pathGroups`
let accGetFn = ctx.getAccountFn
for w in pGroups:
# Special case: fetch account node
if w.slotPaths.len == 0:
yield (rootKey, accGetFn, w.accPath, 0)
continue
# Compile account key
var accKey: NodeKey
if accKey.init(w.accPath):
# Derive slot specs from accounts
let rc = ctx.getSlotsSpecs(rootKey, accGetFn, accKey)
if rc.isOk:
# Loop over slot paths
for path in w.slotPaths:
when extraTraceMessages:
trace logTxt "doTrieNodeSpecs",
rootKey=rc.value.stoRoot, slotPath=path.toHex
yield (rc.value.stoRoot, rc.value.slotFn, path, w.slotPaths.len)
continue
# Fail on this group
when extraTraceMessages:
trace logTxt "doTrieNodeSpecs (blind)", accPath=w.accPath.toHex,
nBlind=w.slotPaths.len, nBlind0=w.slotPaths[0].toHex
yield (NodeKey.default, nil, EmptyBlob, w.slotPaths.len)
proc mkNodeTagRange(
origin: openArray[byte];
limit: openArray[byte];
nAccounts = 1;
): Result[NodeTagRange,void] =
## Verify and convert range arguments to interval
var (minPt, maxPt) = (low(NodeTag), high(NodeTag))
if 0 < origin.len or 0 < limit.len:
# Range applies only if there is exactly one account. A number of accounts
# different from 1 may be used by `getStorageRanges()`
if nAccounts == 0:
return err() # oops: no account
# Verify range arguments
if not minPt.init(origin) or not maxPt.init(limit) or maxPt < minPt:
when extraTraceMessages:
trace logTxt "mkNodeTagRange: malformed range",
origin=origin.toHex, limit=limit.toHex
return err()
if 1 < nAccounts:
return ok(NodeTagRange.new(low(NodeTag), high(NodeTag)))
ok(NodeTagRange.new(minPt, maxPt))
proc fetchLeafRange(
ctx: SnapWireRef; # Handler descriptor
getFn: HexaryGetFn; # Database abstraction
rootKey: NodeKey; # State root
iv: NodeTagRange; # Proofed range of leaf paths
replySizeMax: int; # Updated size counter for the raw list
stopAt: Moment; # Implies timeout
): Result[RangeProof,HexaryError]
{.gcsafe, raises: [CatchableError].} =
## Generic leaf fetcher
let
sizeMax = replySizeMax - estimatedProofSize
now = Moment.now()
timeout = if now < stopAt: stopAt - now else: 1.milliseconds
rc = getFn.hexaryRangeLeafsProof(rootKey, iv, sizeMax, timeout)
if rc.isErr:
error logTxt "fetchLeafRange: database problem",
iv, replySizeMax, error=rc.error
return rc # database error
let sizeOnWire = rc.value.leafsSize + rc.value.proofSize
if sizeOnWire <= replySizeMax:
return rc
# Estimate the overhead size on wire needed for a single leaf tail item
const leafExtraSize = (sizeof RangeLeaf()) - (sizeof newSeq[Blob](0))
let nLeafs = rc.value.leafs.len
when extraTraceMessages:
trace logTxt "fetchLeafRange: reducing reply sample",
iv, sizeOnWire, replySizeMax, nLeafs
# Strip parts of leafs result and amend remainder by adding proof nodes
var (tailSize, tailItems, reduceBy) = (0, 0, replySizeMax - sizeOnWire)
while tailSize <= reduceBy:
tailItems.inc
if nLeafs <= tailItems:
when extraTraceMessages:
trace logTxt "fetchLeafRange: stripping leaf list failed",
iv, replySizeMax, nLeafs, tailItems
return err(DataSizeError) # empty tail (package size too small)
tailSize += rc.value.leafs[^tailItems].data.len + leafExtraSize
# Provide truncated leafs list
let
leafProof = getFn.hexaryRangeLeafsProof(
rootKey, RangeProof(leafs: rc.value.leafs[0 ..< nLeafs - tailItems]))
strippedSizeOnWire = leafProof.leafsSize + leafProof.proofSize
if strippedSizeOnWire <= replySizeMax:
return ok(leafProof)
when extraTraceMessages:
trace logTxt "fetchLeafRange: data size problem",
iv, replySizeMax, nLeafs, tailItems, strippedSizeOnWire
err(DataSizeError)
# ------------------------------------------------------------------------------
# Private functions: peer observer
# ------------------------------------------------------------------------------
#proc onPeerConnected(ctx: SnapWireRef, peer: Peer) =
# debug "snapWire: add peer", peer
# discard
#
#proc onPeerDisconnected(ctx: SnapWireRef, peer: Peer) =
# debug "snapWire: remove peer", peer
# discard
#
#proc setupPeerObserver(ctx: SnapWireRef) =
# var po = PeerObserver(
# onPeerConnected:
# proc(p: Peer) {.gcsafe.} =
# ctx.onPeerConnected(p),
# onPeerDisconnected:
# proc(p: Peer) {.gcsafe.} =
# ctx.onPeerDisconnected(p))
# po.setProtocol protocol.snap
# ctx.peerPool.addObserver(ctx, po)
# ------------------------------------------------------------------------------
# Public constructor/destructor
# ------------------------------------------------------------------------------
proc init*(
T: type SnapWireRef;
chain: ChainRef;
peerPool: PeerPool;
): T =
## Constructor (uses `init()` as suggested in style guide.)
let ctx = T(
chain: chain,
elaFetchMax: defaultElaFetchMax,
dataSizeMax: defaultDataSizeMax,
peerPool: peerPool)
#ctx.setupPeerObserver()
ctx
# ------------------------------------------------------------------------------
# Public functions: helpers
# ------------------------------------------------------------------------------
proc proofEncode*(proof: seq[SnapProof]): Blob =
var writer = initRlpWriter()
writer.snapAppend SnapProofNodes(nodes: proof)
writer.finish
proc proofDecode*(data: Blob): seq[SnapProof] {.gcsafe, raises: [RlpError].} =
var reader = data.rlpFromBytes
reader.snapRead(SnapProofNodes).nodes
# ------------------------------------------------------------------------------
# Public functions: snap wire protocol handlers
# ------------------------------------------------------------------------------
method getAccountRange*(
ctx: SnapWireRef;
root: Hash256;
origin: openArray[byte];
limit: openArray[byte];
replySizeMax: uint64;
): (seq[SnapAccount], SnapProofNodes)
{.gcsafe, raises: [CatchableError].} =
## Fetch accounts list from database
let sizeMax = min(replySizeMax, ctx.dataSizeMax.uint64).int
if sizeMax <= estimatedProofSize:
when extraTraceMessages:
trace logTxt "getAccountRange: max data size too small",
origin=origin.toHex, limit=limit.toHex, sizeMax
return # package size too small
let
rootKey = root.to(NodeKey)
iv = block: # Calculate effective accounts range (if any)
let rc = origin.mkNodeTagRange limit
if rc.isErr:
return # malformed interval
rc.value
stopAt = Moment.now() + ctx.elaFetchMax
rc = ctx.fetchLeafRange(ctx.getAccountFn, rootKey, iv, sizeMax, stopAt)
if rc.isErr:
return # extraction failed
let
accounts = rc.value.leafs.mapIt(it.to(SnapAccount))
proof = rc.value.proof
#when extraTraceMessages:
# trace logTxt "getAccountRange: done", iv, replySizeMax,
# nAccounts=accounts.len, nProof=proof.len
(accounts, SnapProofNodes(nodes: proof))
method getStorageRanges*(
ctx: SnapWireRef;
root: Hash256;
accounts: openArray[Hash256];
origin: openArray[byte];
limit: openArray[byte];
replySizeMax: uint64;
): (seq[seq[SnapStorage]], SnapProofNodes)
{.gcsafe, raises: [CatchableError].} =
## Fetch storage slots list from database
let sizeMax = min(replySizeMax, ctx.dataSizeMax.uint64).int
if sizeMax <= estimatedProofSize:
when extraTraceMessages:
trace logTxt "getStorageRanges: max data size too small",
origin=origin.toHex, limit=limit.toHex, sizeMax
return # package size too small
let
iv = block: # Calculate effective slots range (if any)
let rc = origin.mkNodeTagRange(limit, accounts.len)
if rc.isErr:
return # malformed interval
rc.value
rootKey = root.to(NodeKey)
accGetFn = ctx.getAccountFn
stopAt = Moment.now() + ctx.elaFetchMax
# Loop over accounts
var
dataAllocated = 0
timeExceeded = false
slotLists: seq[seq[SnapStorage]]
proof: seq[SnapProof]
for accHash in accounts:
let sp = block:
let rc = ctx.getSlotsSpecs(rootKey, accGetFn, accHash.to(NodeKey))
if rc.isErr:
slotLists.add emptySnapStorageList
dataAllocated.inc # empty list
continue
rc.value
# Collect data slots for this account => `rangeProof`
let
sizeLeft = sizeMax - dataAllocated
rangeProof = block:
let rc = ctx.fetchLeafRange(sp.slotFn, sp.stoRoot, iv, sizeLeft, stopAt)
if rc.isErr:
when extraTraceMessages:
trace logTxt "getStorageRanges: failed", iv, sizeMax, sizeLeft,
accKey=accHash.to(NodeKey), stoRoot=sp.stoRoot, error=rc.error
return # extraction failed
rc.value
# Process data slots for this account
dataAllocated += rangeProof.leafsSize
when extraTraceMessages:
trace logTxt "getStorageRanges: data slots", iv, sizeMax, dataAllocated,
nAccounts=accounts.len, accKey=accHash.to(NodeKey), stoRoot=sp.stoRoot,
nSlots=rangeProof.leafs.len, nProof=rangeProof.proof.len
slotLists.add rangeProof.leafs.mapIt(it.to(SnapStorage))
if 0 < rangeProof.proof.len:
proof = rangeProof.proof
break # only last entry has a proof
# Stop unless there is enough space left
if sizeMax - dataAllocated <= estimatedProofSize:
break
if stopAt <= Moment.now():
timeExceeded = true
break
when extraTraceMessages:
trace logTxt "getStorageRanges: done", iv, sizeMax, dataAllocated,
nAccounts=accounts.len, nLeafLists=slotLists.len, nProof=proof.len,
timeExceeded
(slotLists, SnapProofNodes(nodes: proof))
method getByteCodes*(
ctx: SnapWireRef;
nodes: openArray[Hash256];
replySizeMax: uint64;
): seq[Blob]
{.gcsafe, raises: [CatchableError].} =
## Fetch contract codes from the database
let
sizeMax = min(replySizeMax, ctx.dataSizeMax.uint64).int
pfxMax = (hexaryRangeRlpSize sizeMax) - sizeMax # RLP list/blob pfx max
effSizeMax = sizeMax - pfxMax
stopAt = Moment.now() + ctx.elaFetchMax
getFn = ctx.getCodeFn
var
dataAllocated = 0
timeExceeded = false
when extraTraceMessages:
trace logTxt "getByteCodes", sizeMax, nNodes=nodes.len
for w in nodes:
let data = w.data.toSeq.getFn
if 0 < data.len:
let effDataLen = hexaryRangeRlpSize data.len
if effSizeMax - effDataLen < dataAllocated:
break
dataAllocated += effDataLen
result.add data
else:
when extraTraceMessages:
trace logTxt "getByteCodes: empty record", sizeMax, nNodes=nodes.len,
key=w
if stopAt <= Moment.now():
timeExceeded = true
break
when extraTraceMessages:
trace logTxt "getByteCodes: done", sizeMax, dataAllocated,
nNodes=nodes.len, nResult=result.len, timeExceeded
method getTrieNodes*(
ctx: SnapWireRef;
root: Hash256;
pathGroups: openArray[SnapTriePaths];
replySizeMax: uint64;
): seq[Blob]
{.gcsafe, raises: [CatchableError].} =
## Fetch nodes from the database
let
sizeMax = min(replySizeMax, ctx.dataSizeMax.uint64).int
someSlack = sizeMax.hexaryRangeRlpSize() - sizeMax
if sizeMax <= someSlack:
when extraTraceMessages:
trace logTxt "getTrieNodes: max data size too small",
root=root.to(NodeKey), nPathGroups=pathGroups.len, sizeMax, someSlack
return # package size too small
let
rootKey = root.to(NodeKey)
effSizeMax = sizeMax - someSlack
stopAt = Moment.now() + ctx.elaFetchMax
var
dataAllocated = 0
timeExceeded = false
logPartPath: seq[Blob]
for (stateKey,getFn,partPath,n) in ctx.doTrieNodeSpecs(rootKey, pathGroups):
# Special case: no data available
if getFn.isNil:
if effSizeMax < dataAllocated + n:
break # no need to add trailing empty nodes
result &= EmptyBlob.repeat(n)
dataAllocated += n
continue
# Fetch node blob
let node = block:
let steps = partPath.hexPrefixDecode[1].hexaryPath(stateKey, getFn)
if 0 < steps.path.len and
steps.tail.len == 0 and steps.path[^1].nibble < 0:
steps.path[^1].node.convertTo(Blob)
else:
EmptyBlob
if effSizeMax < dataAllocated + node.len:
break
if stopAt <= Moment.now():
timeExceeded = true
break
result &= node
when extraTraceMessages:
trace logTxt "getTrieNodes: done", sizeMax, dataAllocated,
nGroups=pathGroups.mapIt(max(1,it.slotPaths.len)).foldl(a+b,0),
nPaths=pathGroups.len, nResult=result.len, timeExceeded
# ------------------------------------------------------------------------------
# End
# ------------------------------------------------------------------------------