Add sender address derivation for several RPCs

nimbus/rpc/p2p.nim

@@ -33,6 +33,29 @@ func toHash(value: array[32, byte]): Hash256 {.inline.} =
 func strToHash(value: string): Hash256 {.inline.} =
   result = hexToPaddedByteArray[32](value).toHash
 
+
+template toSignature(transaction: Transaction): Signature =
+  var bytes: array[65, byte]
+  bytes[0..31] = cast[array[32, byte]](transaction.R)
+  bytes[32..63] = cast[array[32, byte]](transaction.S)
+  #[
+    TODO: In the yellow paper:
+      It is assumed that v is the ‘recovery id’, a 1 byte value
+      specifying the sign and finiteness of the curve point; this
+      value is in the range of [27,30].
+    Does this need to be checked that it is [0, 1] and inc by 27?
+  ]#
+  # TODO: Ugly casting below, is there a better way/helper func?
+  bytes[64] = (cast[uint64](transaction.V.data.lo) and 0xff'u64).uint8
+  initSignature(bytes)
+
+proc getSender(transaction: Transaction, txHash: Hash256): EthAddress =
+  let
+    sig = transaction.toSignature()
+    pubKey = recoverKeyFromSignature(sig, txHash)
+  const pubKeySize = 64
+  result[0..19] = pubKey.data[pubKeySize - 20 .. pubKeySize - 1]
+
 func headerFromTag(chain:BaseChainDB, blockTag: string): BlockHeader =
   let tag = blockTag.toLowerAscii
   case tag
@@ -319,7 +342,7 @@ proc setupP2PRPC*(node: EthereumNode, rpcsrv: RpcServer) =
       raise newException(ValueError, "Cannot find hash")
     populateBlockObject(header, body)
 
-  func populateTransactionObject(transaction: Transaction, txHash: Hash256, txCount: UInt256, txIndex: int, blockHeader: BlockHeader, gas: int64): TransactionObject =
+  proc populateTransactionObject(transaction: Transaction, txHash: Hash256, txCount: UInt256, txIndex: int, blockHeader: BlockHeader, gas: int64): TransactionObject =
     result.hash = txHash
     result.nonce = txCount
     result.blockHash = new Hash256
@@ -328,8 +351,7 @@ proc setupP2PRPC*(node: EthereumNode, rpcsrv: RpcServer) =
     result.blockNumber[] = blockHeader.blockNumber
     result.transactionIndex = new int64
     result.transactionIndex[] = txIndex
-    # TODO: Fetch or calculate `from` address with signature after signing with the private key
-    #result.source: EthAddress
+    result.source = transaction.getSender(transaction.rlpHash)
     result.to = new EthAddress
     result.to[] = transaction.to
     result.value = transaction.value
@@ -354,8 +376,7 @@ proc setupP2PRPC*(node: EthereumNode, rpcsrv: RpcServer) =
       transaction = body.transactions[txDetails.index]
       vmState = newBaseVMState(header, chain)
       addressDb = vmState.chaindb.getStateDb(blockHash, true)
-      # TODO: Get/calculate address for this transaction
-      address = ZERO_ADDRESS  
+      address = transaction.getSender(transaction.rlpHash)
       txCount = addressDb.getNonce(address)
       txHash = transaction.rlpHash
       # TODO: Fetch account gas
@@ -378,8 +399,7 @@ proc setupP2PRPC*(node: EthereumNode, rpcsrv: RpcServer) =
       transaction = body.transactions[quantity]
       vmState = newBaseVMState(header, chain)
       addressDb = vmState.chaindb.getStateDb(blockHash, true)
-      # TODO: Get/calculate address for this transaction
-      address = ZERO_ADDRESS  
+      address = transaction.getSender(transaction.rlpHash) 
       txCount = addressDb.getNonce(address)
       txHash = transaction.rlpHash
       # TODO: Fetch account gas
@@ -401,36 +421,13 @@ proc setupP2PRPC*(node: EthereumNode, rpcsrv: RpcServer) =
       transaction = body.transactions[quantity]
       vmState = newBaseVMState(header, chain)
       addressDb = vmState.chaindb.getStateDb(blockHash, true)
-      # TODO: Get/calculate address for this transaction
-      address = ZERO_ADDRESS  
+      address = transaction.getSender(transaction.rlpHash)
       txCount = addressDb.getNonce(address)
       txHash = transaction.rlpHash
       # TODO: Fetch account gas
       accountGas = 0  
     populateTransactionObject(transaction, txHash, txCount, quantity, header, accountGas)
 
-  template toSignature(transaction: Transaction): Signature =
-    var bytes: array[65, byte]
-    bytes[0..31] = cast[array[32, byte]](transaction.R)
-    bytes[32..63] = cast[array[32, byte]](transaction.S)
-    #[
-      TODO: In the yellow paper:
-        It is assumed that v is the ‘recovery id’, a 1 byte value
-        specifying the sign and finiteness of the curve point; this
-        value is in the range of [27,30].
-      Does this need to be checked that it is [0, 1] and inc by 27?
-    ]#
-    # TODO: Ugly casting below, is there a better way/helper func?
-    bytes[64] = (cast[uint64](transaction.V.data.lo) and 0xff'u64).uint8
-    initSignature(bytes)
-
-  proc getSender(transaction: Transaction, txHash: Hash256): EthAddress =
-    let
-      sig = transaction.toSignature()
-      pubKey = recoverKeyFromSignature(sig, txHash)
-    const pubKeySize = 64
-    result[0..19] = pubKey.data[pubKeySize - 20 .. pubKeySize - 1]
-
   proc populateReceipt(receipt: Receipt, cumulativeGas: GasInt, transaction: Transaction, txIndex: int, blockHeader: BlockHeader): ReceiptObject =
     result.transactionHash = transaction.rlpHash
     result.transactionIndex = txIndex