Added helper functions to check if a tx spents p2pkh input

UlordChain · Jul 28, 2018 · 1958d1a · 1958d1a
1 parent d6b1768
commit 1958d1a
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Showing 2 changed files with 39 additions and 9 deletions.
diff --git a/uscj-core/src/main/java/co/usc/peg/BridgeSupport.java b/uscj-core/src/main/java/co/usc/peg/BridgeSupport.java
@@ -415,9 +415,9 @@ public void registerUldTransaction(Transaction uscTx, byte[] uldTxSerialized, in
         }
 
         // Check there are at least N blocks on top of the supplied height
-        int headHeight = uldBlockChain.getBestChainHeight();
-        if ((headHeight - height + 1) < bridgeConstants.getUld2UscMinimumAcceptableConfirmations()) {
-            logger.warn("At least " + bridgeConstants.getUld2UscMinimumAcceptableConfirmations() + " confirmations are required, but there are only " + (headHeight - height) + " confirmations");
+        int confirmations = uldBlockChain.getBestChainHeight() - height + 1;
+        if (confirmations < bridgeConstants.getUld2UscMinimumAcceptableConfirmations()) {
+            logger.warn("At least " + bridgeConstants.getUld2UscMinimumAcceptableConfirmations() + " confirmations are required, but there are only " + confirmations + " confirmations");
             return;
         }
 
@@ -439,8 +439,8 @@ public void registerUldTransaction(Transaction uscTx, byte[] uldTxSerialized, in
         // Specific code for lock/release/none txs
         if (BridgeUtils.isLockTx(uldTx, getLiveFederations(), uldContext, bridgeConstants)) {
             logger.debug("This is a lock tx {}", uldTx);
-            Script scriptSig = uldTx.getInput(0).getScriptSig();
-            if (scriptSig.getChunks().size() != 2) {
+            Optional<Script> scriptSig = BridgeUtils.getFirstInputScriptSig(uldTx);
+            if (!scriptSig.isPresent()) {
 			  logger.warn("[uldlock:{}] First input does not spend a Pay-to-PubkeyHash " + uldTx.getInput(0), uldTx.getHash());
               return;
             }
@@ -457,7 +457,7 @@ public void registerUldTransaction(Transaction uscTx, byte[] uldTxSerialized, in
             Coin totalAmount = amountToActive.add(amountToRetiring);
 
             // Get the sender public key
-            byte[] data = scriptSig.getChunks().get(1).data;
+            byte[] data = scriptSig.get().getChunks().get(1).data;
 
             // Tx is a lock tx, check whether the sender is whitelisted
             UldECKey senderUldKey = UldECKey.fromPublicOnly(data);

diff --git a/uscj-core/src/main/java/co/usc/peg/BridgeUtils.java b/uscj-core/src/main/java/co/usc/peg/BridgeUtils.java
@@ -21,7 +21,6 @@
 import co.usc.ulordj.core.*;
 import co.usc.ulordj.script.Script;
 import co.usc.ulordj.store.BlockStoreException;
-import co.usc.ulordj.store.UldBlockStore;
 import co.usc.ulordj.wallet.Wallet;
 import co.usc.config.BridgeConstants;
 import co.usc.core.UscAddress;
@@ -33,11 +32,12 @@
 import org.ethereum.vm.PrecompiledContracts;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
+import org.spongycastle.util.encoders.Hex;
 
 import java.util.Arrays;
 import java.util.List;
-import java.util.HashMap;
 import java.util.Map;
+import java.util.Optional;
 
 /**
  * @author Oscar Guindzberg
@@ -130,6 +130,36 @@ private static boolean scriptCorrectlySpendsTx(UldTransaction tx, int index, Scr
         }
     }
 
+    /**
+     * Indicates whether a tx is a valid lock tx or not, checking the first input's script sig
+     * @param tx
+     * @return
+     */
+    public static boolean isValidLockTx(UldTransaction tx) {
+        if (tx.getInputs().size() == 0) {
+            return false;
+        }
+        // This indicates that the tx is a P2PKH transaction which is the only one we support for now
+        if (tx.getInput(0).getScriptSig().getChunks().size() != 2) {
+            logger.warn("[btctx:{}] is not a valid lock tx and won't be processed!", Hex.toHexString(tx.getHash().getBytes()));
+            return false;
+        }
+        return true;
+    }
+
+    /**
+     * Will return a valid scriptsig for the first input
+     * @param tx
+     * @return
+     */
+    public static Optional<Script> getFirstInputScriptSig(UldTransaction tx) {
+        if (!isValidLockTx(tx)) {
+            return Optional.empty();
+        }
+        return Optional.of(tx.getInput(0).getScriptSig());
+    }
+
+
     public static boolean isLockTx(UldTransaction tx, List<Federation> federations, Context uldContext, BridgeConstants bridgeConstants) {
         // First, check tx is not a typical release tx (tx spending from the any of the federation addresses and
         // optionally sending some change to any of the federation addresses)
@@ -145,7 +175,7 @@ public static boolean isLockTx(UldTransaction tx, List<Federation> federations,
 
         int valueSentToMeSignum = valueSentToMe.signum();
         if (valueSentToMe.isLessThan(bridgeConstants.getMinimumLockTxValue())) {
-            logger.warn("Someone sent to the federation less than {} satoshis", bridgeConstants.getMinimumLockTxValue());
+            logger.warn("[uldtx:{}]Someone sent to the federation less than {} satoshis", Hex.toHexString(tx.getHash().getBytes()), bridgeConstants.getMinimumLockTxValue());
         }
         return (valueSentToMeSignum > 0 && !valueSentToMe.isLessThan(bridgeConstants.getMinimumLockTxValue()));
     }