fix(rln-relay): RLN DB should be aware of chain and contract address (#1932)

tests/waku_rln_relay/test_rln_group_manager_onchain.nim

@@ -197,6 +197,29 @@ suite "Onchain group manager":
       manager.membershipFee.isSome()
       manager.initialized
 
+  asyncTest "should error on initialization when loaded metadata does not match":
+    let manager = await setup()
+    await manager.init()
+
+    let metadataSetRes = manager.setMetadata()
+    assert metadataSetRes.isOk(), metadataSetRes.error
+    let metadataRes = manager.rlnInstance.getMetadata()
+    assert metadataRes.isOk(), metadataRes.error
+    let metadata = metadataRes.get()
+    require:
+      metadata.chainId == 1337
+      metadata.contractAddress == manager.ethContractAddress
+    
+    await manager.stop()
+    
+    # simulating a change in the contractAddress
+    let manager2 = OnchainGroupManager(ethClientUrl: EthClient,
+                                       ethContractAddress: "0x0000000000000000000000000000000000000000",
+                                       ethPrivateKey: manager.ethPrivateKey,
+                                       rlnInstance: manager.rlnInstance,
+                                       saveKeystore: false)
+    expect(ValueError): await manager2.init()
+
   asyncTest "startGroupSync: should start group sync":
     let manager = await setup()
 

tests/waku_rln_relay/test_waku_rln_relay.nim

@@ -245,7 +245,9 @@ suite "Waku rln relay":
       rlnInstance.isOk()
     let rln = rlnInstance.get()
     check:
-      rln.setMetadata(RlnMetadata(lastProcessedBlock: 128)).isOk()
+      rln.setMetadata(RlnMetadata(lastProcessedBlock: 128,
+                                  chainId: 1155511,
+                                  contractAddress: "0x9c09146844c1326c2dbc41c451766c7138f88155")).isOk()
 
   test "getMetadata rln utils":
     # create an RLN instance which also includes an empty Merkle tree
@@ -255,7 +257,9 @@ suite "Waku rln relay":
     let rln = rlnInstance.get()
 
     require:
-      rln.setMetadata(RlnMetadata(lastProcessedBlock: 128)).isOk()
+      rln.setMetadata(RlnMetadata(lastProcessedBlock: 128,
+                                  chainId: 1155511,
+                                  contractAddress: "0x9c09146844c1326c2dbc41c451766c7138f88155")).isOk()
 
     let metadataRes = rln.getMetadata()
 
@@ -266,7 +270,8 @@ suite "Waku rln relay":
 
     check:
       metadata.lastProcessedBlock == 128
-
+      metadata.chainId == 1155511
+      metadata.contractAddress == "0x9c09146844c1326c2dbc41c451766c7138f88155"
 
   test "Merkle tree consistency check between deletion and insertion":
     # create an RLN instance

waku/waku_rln_relay/group_manager/on_chain/group_manager.nim

@@ -12,7 +12,8 @@ import
   json,
   std/tables,
   stew/[byteutils, arrayops],
-  sequtils
+  sequtils,
+  strutils
 import
   ../../../waku_keystore,
   ../../rln,
@@ -281,6 +282,20 @@ proc handleRemovedEvents(g: OnchainGroupManager, blockTable: BlockTable): Future
 
   await g.backfillRootQueue(numRemovedBlocks)
 
+proc setMetadata*(g: OnchainGroupManager): RlnRelayResult[void] =
+  if g.latestProcessedBlock.isNone():
+    return err("latest processed block is not set")
+  try:
+    let metadataSetRes = g.rlnInstance.setMetadata(RlnMetadata(
+                            lastProcessedBlock: g.latestProcessedBlock.get(),
+                            chainId: uint64(g.chainId.get()),
+                            contractAddress: g.ethContractAddress))
+    if metadataSetRes.isErr():
+      return err("failed to persist rln metadata: " & metadataSetRes.error())
+  except CatchableError:
+    return err("failed to persist rln metadata: " & getCurrentExceptionMsg())
+  return ok()
+
 proc getAndHandleEvents(g: OnchainGroupManager,
                         fromBlock: BlockNumber,
                         toBlock: Option[BlockNumber] = none(BlockNumber)): Future[void] {.async.} =
@@ -293,8 +308,7 @@ proc getAndHandleEvents(g: OnchainGroupManager,
   let latestProcessedBlock = if toBlock.isSome(): toBlock.get()
                              else: fromBlock
   g.latestProcessedBlock = some(latestProcessedBlock)
-  let metadataSetRes = g.rlnInstance.setMetadata(RlnMetadata(
-                          lastProcessedBlock: latestProcessedBlock))
+  let metadataSetRes = g.setMetadata()
   if metadataSetRes.isErr():
     # this is not a fatal error, hence we don't raise an exception
     warn "failed to persist rln metadata", error=metadataSetRes.error()
@@ -465,17 +479,8 @@ method init*(g: OnchainGroupManager): Future[void] {.async.} =
   let contractAddress = web3.fromHex(web3.Address, g.ethContractAddress)
   contract = ethRpc.contractSender(RlnContract, contractAddress)
 
-  # check if the contract exists by calling a static function
-  var membershipFee: Uint256
-  try:
-    membershipFee = await contract.MEMBERSHIP_DEPOSIT().call()
-  except CatchableError:
-    raise newException(ValueError, "could not get the membership deposit: {}")
-
-
   g.ethRpc = some(ethRpc)
   g.rlnContract = some(contract)
-  g.membershipFee = some(membershipFee)
 
   if g.keystorePath.isSome() and g.keystorePassword.isSome():
     waku_rln_membership_credentials_import_duration_seconds.nanosecondTime:
@@ -498,8 +503,22 @@ method init*(g: OnchainGroupManager): Future[void] {.async.} =
     g.latestProcessedBlock = some(BlockNumber(0))
   else:
     let metadata = metadataGetRes.get()
+    if metadata.chainId != uint64(g.chainId.get()):
+      raise newException(ValueError, "persisted data: chain id mismatch")
+  
+    if metadata.contractAddress != g.ethContractAddress.toLower():
+      raise newException(ValueError, "persisted data: contract address mismatch")
     g.latestProcessedBlock = some(metadata.lastProcessedBlock)
 
+  # check if the contract exists by calling a static function
+  var membershipFee: Uint256
+  try:
+    membershipFee = await contract.MEMBERSHIP_DEPOSIT().call()
+  except CatchableError:
+    raise newException(ValueError, 
+                       "could not get the membership deposit: " & getCurrentExceptionMsg())
+  g.membershipFee = some(membershipFee)
+
   ethRpc.ondisconnect = proc() =
     error "Ethereum client disconnected"
     let fromBlock = g.latestProcessedBlock.get()

waku/waku_rln_relay/rln/wrappers.nim

@@ -3,7 +3,9 @@ import
 import
   chronicles,
   options,
-  stew/[arrayops, results],
+  eth/keys,
+  stew/[arrayops, byteutils, results, endians2],
+  std/[sequtils, strformat, strutils, tables],
   nimcrypto/utils
 
 import
@@ -120,7 +122,6 @@ proc createRLNInstance*(d = MerkleTreeDepth,
 
 proc sha256*(data: openArray[byte]): RlnRelayResult[MerkleNode] =
   ## a thin layer on top of the Nim wrapper of the sha256 hasher
-  trace "sha256 hash input", hashhex = data.toHex()
   var lenPrefData = encodeLengthPrefix(data)
   var
     hashInputBuffer = lenPrefData.toBuffer()
@@ -247,7 +248,7 @@ proc proofVerify*(rlnInstance: ptr RLN,
     rootsBytes = serialize(validRoots)
     rootsBuffer = rootsBytes.toBuffer()
 
-  trace "serialized proof", proof = proofBytes.toHex()
+  trace "serialized proof", proof = byteutils.toHex(proofBytes)
 
   let verifyIsSuccessful = verify_with_roots(rlnInstance, addr proofBuffer, addr rootsBuffer, addr validProof)
   if not verifyIsSuccessful:
@@ -350,11 +351,15 @@ proc getMerkleRoot*(rlnInstance: ptr RLN): MerkleNodeResult =
 type
   RlnMetadata* = object
     lastProcessedBlock*: uint64
+    chainId*: uint64
+    contractAddress*: string
 
 proc serialize(metadata: RlnMetadata): seq[byte] =
   ## serializes the metadata
   ## returns the serialized metadata
-  return @(metadata.lastProcessedBlock.toBytes())
+  return concat(@(metadata.lastProcessedBlock.toBytes()),
+                @(metadata.chainId.toBytes()),
+                @(hexToSeqByte(toLower(metadata.contractAddress))))
 
 proc setMetadata*(rlnInstance: ptr RLN, metadata: RlnMetadata): RlnRelayResult[void] =
   ## sets the metadata of the RLN instance
@@ -368,6 +373,7 @@ proc setMetadata*(rlnInstance: ptr RLN, metadata: RlnMetadata): RlnRelayResult[v
 
   # set the metadata
   let metadataSet = set_metadata(rlnInstance, metadataBufferPtr)
+
   if not metadataSet:
     return err("could not set the metadata")
   return ok()
@@ -384,8 +390,26 @@ proc getMetadata*(rlnInstance: ptr RLN): RlnRelayResult[RlnMetadata] =
     getMetadataSuccessful = get_metadata(rlnInstance, metadataPtr)
   if not getMetadataSuccessful:
     return err("could not get the metadata")
-  if not metadata.len == 8:
+  if not metadata.len == 36:
     return err("wrong output size")
 
-  var metadataValue = cast[ptr uint64] (metadata.`ptr`)[]
-  return ok(RlnMetadata(lastProcessedBlock: metadataValue))
+  let 
+    lastProcessedBlockOffset = 0
+    chainIdOffset = lastProcessedBlockOffset + 8
+    contractAddressOffset = chainIdOffset + 8
+  
+  var
+    lastProcessedBlock: uint64
+    chainId: uint64
+    contractAddress: string
+
+  var metadataValue = cast[ptr array[36, byte]] (metadata.`ptr`)
+  let metadataBytes: array[36, byte] = metadataValue[]
+
+  lastProcessedBlock = uint64.fromBytes(metadataBytes[lastProcessedBlockOffset..chainIdOffset-1])
+  chainId = uint64.fromBytes(metadataBytes[chainIdOffset..contractAddressOffset-1])
+  contractAddress = byteutils.toHex(metadataBytes[contractAddressOffset..metadataBytes.high])
+
+  return ok(RlnMetadata(lastProcessedBlock: lastProcessedBlock,
+                        chainId: chainId,
+                        contractAddress: "0x" & contractAddress))