Validate announcement signatures on create/accept offer (#4071)

* Validate announcement signatures on create/accept offer

* unit tests

dlc-wallet-test/src/test/scala/org/bitcoins/dlc/wallet/WalletDLCSetupTest.scala

@@ -9,6 +9,7 @@ import org.bitcoins.core.protocol.tlv._
 import org.bitcoins.core.wallet.fee.SatoshisPerVirtualByte
 import org.bitcoins.core.wallet.utxo.TxoState
 import org.bitcoins.crypto._
+import org.bitcoins.dlc.wallet.DLCWallet.InvalidAnnouncementSignature
 import org.bitcoins.dlc.wallet.internal.DLCDataManagement
 import org.bitcoins.testkit.wallet.DLCWalletUtil._
 import org.bitcoins.testkit.wallet.FundWalletUtil.FundedDLCWallet
@@ -856,4 +857,50 @@ class WalletDLCSetupTest extends BitcoinSDualWalletTest {
     } yield res
   }
 
+  it must "fail to create an offer with an invalid announcement signature" in {
+    wallets =>
+      val walletA = wallets._1.wallet
+
+      val offerData: DLCOffer = DLCWalletUtil.invalidDLCOffer
+
+      for {
+        res <- recoverToSucceededIf[InvalidAnnouncementSignature](
+          walletA.createDLCOffer(
+            offerData.contractInfo,
+            offerData.totalCollateral,
+            Some(offerData.feeRate),
+            offerData.timeouts.contractMaturity.toUInt32,
+            UInt32.max
+          ))
+      } yield {
+        res
+      }
+  }
+
+  it must "fail to accept an offer with an invalid announcement signature" in {
+    wallets =>
+      val walletA = wallets._1.wallet
+      val walletB = wallets._2.wallet
+
+      //https://test.oracle.suredbits.com/contract/enum/75b08299654dca23b80cf359db6afb6cfd6e55bc898b5397d3c0fe796dfc13f0/12fb3e5f091086329ed0d2a12c3fcfa80111a36ef3fc1ac9c2567076a57d6a73
+      val contractInfo = ContractInfoV0TLV.fromHex(
+        "fdd82eeb00000000000186a0fda71026030359455300000000000186a0024e4f0000000000000000056f746865720000000000000000fda712b5fdd824b1596ec40d0dae3fdf54d9795ad51ec069970c6863a02d244663d39fd6bedadc0070349e1ba2e17583ee2d1cb3ae6fffaaa1c45039b61c5c4f1d0d864221c461745d1bcfab252c6dd9edd7aea4c5eeeef138f7ff7346061ea40143a9f5ae80baa9fdd8224d0001fa5b84283852400b21a840d5d5ca1cc31867c37326ad521aa50bebf3df4eea1a60b03280fdd8060f000303594553024e4f056f74686572135465746865722d52657365727665732d363342")
+      val feeRateOpt = Some(SatoshisPerVirtualByte(Satoshis.one))
+      val totalCollateral = Satoshis(5000)
+
+      for {
+        offer <- walletA.createDLCOffer(contractInfoTLV = contractInfo,
+                                        collateral = totalCollateral,
+                                        feeRateOpt = feeRateOpt,
+                                        locktime = UInt32.zero,
+                                        refundLT = UInt32.one)
+        invalidOffer = offer.copy(contractInfo = invalidContractInfo)
+        res <- recoverToSucceededIf[InvalidAnnouncementSignature](
+          walletB.acceptDLCOffer(invalidOffer))
+      } yield {
+        res
+      }
+
+  }
+
 }

dlc-wallet/src/main/scala/org/bitcoins/dlc/wallet/DLCWallet.scala

@@ -30,6 +30,7 @@ import org.bitcoins.core.wallet.fee.SatoshisPerVirtualByte
 import org.bitcoins.core.wallet.utxo._
 import org.bitcoins.crypto._
 import org.bitcoins.db.SafeDatabase
+import org.bitcoins.dlc.wallet.DLCWallet.InvalidAnnouncementSignature
 import org.bitcoins.dlc.wallet.internal._
 import org.bitcoins.dlc.wallet.models._
 import org.bitcoins.dlc.wallet.util.{
@@ -269,6 +270,12 @@ abstract class DLCWallet
       locktime: UInt32,
       refundLocktime: UInt32): Future[DLCOffer] = {
     logger.info("Creating DLC Offer")
+    if (!validateAnnouncementSignatures(contractInfo.oracleInfos)) {
+      return Future.failed(
+        InvalidAnnouncementSignature(
+          s"Contract info contains invalid announcement signature(s)"))
+    }
+
     val announcements =
       contractInfo.oracleInfos.head.singleOracleInfos.map(_.announcement)
 
@@ -552,6 +559,10 @@ abstract class DLCWallet
     */
   override def acceptDLCOffer(offer: DLCOffer): Future[DLCAccept] = {
     logger.debug("Calculating relevant wallet data for DLC Accept")
+    if (!validateAnnouncementSignatures(offer.oracleInfos)) {
+      return Future.failed(InvalidAnnouncementSignature(
+        s"Offer ${offer.tempContractId.hex} contains invalid announcement signature(s)"))
+    }
 
     val dlcId = calcDLCId(offer.fundingInputs.map(_.outPoint))
 
@@ -575,6 +586,12 @@ abstract class DLCWallet
     } yield dlcAccept
   }
 
+  private def validateAnnouncementSignatures(
+      oracleInfos: Vector[OracleInfo]): Boolean = {
+    oracleInfos.forall(infos =>
+      infos.singleOracleInfos.forall(_.announcement.validateSignature))
+  }
+
   private def fundDLCAcceptMsg(
       offer: DLCOffer,
       collateral: CurrencyUnit,
@@ -1726,6 +1743,9 @@ abstract class DLCWallet
 
 object DLCWallet extends WalletLogger {
 
+  case class InvalidAnnouncementSignature(message: String)
+      extends RuntimeException(message)
+
   private case class DLCWalletImpl(
       nodeApi: NodeApi,
       chainQueryApi: ChainQueryApi,

testkit/src/main/scala/org/bitcoins/testkit/wallet/DLCWalletUtil.scala

@@ -67,12 +67,28 @@ object DLCWalletUtil extends Logging {
                                       rValue,
                                       sampleOutcomes.map(_._1))
 
+  lazy val invalidOracleInfo: EnumSingleOracleInfo = {
+    val info = EnumSingleOracleInfo.dummyForKeys(oraclePrivKey,
+                                                 rValue,
+                                                 sampleOutcomes.map(_._1))
+    val announcement = info.announcement.asInstanceOf[OracleAnnouncementV0TLV]
+    val invalidAnnouncement =
+      announcement.copy(announcementSignature = SchnorrDigitalSignature.dummy)
+    info.copy(announcement = invalidAnnouncement)
+  }
+
   lazy val sampleContractOraclePair: ContractOraclePair.EnumPair =
     ContractOraclePair.EnumPair(sampleContractDescriptor, sampleOracleInfo)
 
+  lazy val invalidContractOraclePair: ContractOraclePair.EnumPair =
+    ContractOraclePair.EnumPair(sampleContractDescriptor, invalidOracleInfo)
+
   lazy val sampleContractInfo: ContractInfo =
     SingleContractInfo(half, sampleContractOraclePair)
 
+  lazy val invalidContractInfo: ContractInfo =
+    SingleContractInfo(half, invalidContractOraclePair)
+
   lazy val sampleOracleWinSig: SchnorrDigitalSignature =
     oraclePrivKey.schnorrSignWithNonce(winHash.bytes, kValue)
 
@@ -164,6 +180,20 @@ object DLCWalletUtil extends Logging {
     timeouts = dummyTimeouts
   )
 
+  lazy val invalidDLCOffer: DLCOffer = DLCOffer(
+    protocolVersionOpt = DLCOfferTLV.currentVersionOpt,
+    contractInfo = invalidContractInfo,
+    pubKeys = dummyDLCKeys,
+    totalCollateral = half,
+    fundingInputs = Vector(dummyFundingInputs.head),
+    changeAddress = dummyAddress,
+    payoutSerialId = sampleOfferPayoutSerialId,
+    changeSerialId = sampleOfferChangeSerialId,
+    fundOutputSerialId = sampleFundOutputSerialId,
+    feeRate = SatoshisPerVirtualByte(Satoshis(3)),
+    timeouts = dummyTimeouts
+  )
+
   lazy val sampleMultiNonceDLCOffer: DLCOffer =
     sampleDLCOffer.copy(contractInfo = multiNonceContractInfo)