[libconsensus] Script verification API with amounts

script_tests: always test bitcoinconsensus_verify_script_with_amount if VERIFY_WITNESS isn't set

Rename internal method + make it static

trim bitcoinconsensus_ prefix

Add SERIALIZE_TRANSACTION_WITNESS flag

Author: afk11

src/script/bitcoinconsensus.cpp

@@ -69,7 +69,7 @@ struct ECCryptoClosure
 ECCryptoClosure instance_of_eccryptoclosure;
 }
 
-int bitcoinconsensus_verify_script(const unsigned char *scriptPubKey, unsigned int scriptPubKeyLen,
+static int verify_script(const unsigned char *scriptPubKey, unsigned int scriptPubKeyLen, CAmount amount,
                                     const unsigned char *txTo        , unsigned int txToLen,
                                     unsigned int nIn, unsigned int flags, bitcoinconsensus_error* err)
 {
@@ -82,16 +82,36 @@ int bitcoinconsensus_verify_script(const unsigned char *scriptPubKey, unsigned i
         if (tx.GetSerializeSize(SER_NETWORK, PROTOCOL_VERSION) != txToLen)
             return set_error(err, bitcoinconsensus_ERR_TX_SIZE_MISMATCH);
 
-         // Regardless of the verification result, the tx did not error.
-         set_error(err, bitcoinconsensus_ERR_OK);
+        // Regardless of the verification result, the tx did not error.
+        set_error(err, bitcoinconsensus_ERR_OK);
 
-        CAmount am(0);
-        return VerifyScript(tx.vin[nIn].scriptSig, CScript(scriptPubKey, scriptPubKey + scriptPubKeyLen), nIn < tx.wit.vtxinwit.size() ? &tx.wit.vtxinwit[nIn].scriptWitness : NULL, flags, TransactionSignatureChecker(&tx, nIn, am), NULL);
+        return VerifyScript(tx.vin[nIn].scriptSig, CScript(scriptPubKey, scriptPubKey + scriptPubKeyLen), nIn < tx.wit.vtxinwit.size() ? &tx.wit.vtxinwit[nIn].scriptWitness : NULL, flags, TransactionSignatureChecker(&tx, nIn, amount), NULL);
     } catch (const std::exception&) {
         return set_error(err, bitcoinconsensus_ERR_TX_DESERIALIZE); // Error deserializing
     }
 }
 
+int bitcoinconsensus_verify_script_with_amount(const unsigned char *scriptPubKey, unsigned int scriptPubKeyLen, int64_t amount,
+                                    const unsigned char *txTo        , unsigned int txToLen,
+                                    unsigned int nIn, unsigned int flags, bitcoinconsensus_error* err)
+{
+    CAmount am(amount);
+    return ::verify_script(scriptPubKey, scriptPubKeyLen, am, txTo, txToLen, nIn, flags, err);
+}
+
+
+int bitcoinconsensus_verify_script(const unsigned char *scriptPubKey, unsigned int scriptPubKeyLen,
+                                   const unsigned char *txTo        , unsigned int txToLen,
+                                   unsigned int nIn, unsigned int flags, bitcoinconsensus_error* err)
+{
+    if (flags & bitcoinconsensus_SCRIPT_FLAGS_VERIFY_WITNESS) {
+        return set_error(err, bitcoinconsensus_ERR_AMOUNT_REQUIRED);
+    }
+
+    CAmount am(0);
+    return ::verify_script(scriptPubKey, scriptPubKeyLen, am, txTo, txToLen, nIn, flags, err);
+}
+
 unsigned int bitcoinconsensus_version()
 {
     // Just use the API version for now

src/script/bitcoinconsensus.h

@@ -33,14 +33,15 @@
 extern "C" {
 #endif
 
-#define BITCOINCONSENSUS_API_VER 0
+#define BITCOINCONSENSUS_API_VER 1
 
 typedef enum bitcoinconsensus_error_t
 {
     bitcoinconsensus_ERR_OK = 0,
     bitcoinconsensus_ERR_TX_INDEX,
     bitcoinconsensus_ERR_TX_SIZE_MISMATCH,
     bitcoinconsensus_ERR_TX_DESERIALIZE,
+    bitcoinconsensus_ERR_AMOUNT_REQUIRED,
 } bitcoinconsensus_error;
 
 /** Script verification flags */
@@ -50,13 +51,18 @@ enum
     bitcoinconsensus_SCRIPT_FLAGS_VERIFY_P2SH                = (1U << 0), // evaluate P2SH (BIP16) subscripts
     bitcoinconsensus_SCRIPT_FLAGS_VERIFY_DERSIG              = (1U << 2), // enforce strict DER (BIP66) compliance
     bitcoinconsensus_SCRIPT_FLAGS_VERIFY_CHECKLOCKTIMEVERIFY = (1U << 9), // enable CHECKLOCKTIMEVERIFY (BIP65)
+    bitcoinconsensus_SCRIPT_FLAGS_VERIFY_WITNESS             = (1U << 11), // enable WITNESS (BIP141)
 };
 
 /// Returns 1 if the input nIn of the serialized transaction pointed to by
 /// txTo correctly spends the scriptPubKey pointed to by scriptPubKey under
 /// the additional constraints specified by flags.
 /// If not NULL, err will contain an error/success code for the operation
 EXPORT_SYMBOL int bitcoinconsensus_verify_script(const unsigned char *scriptPubKey, unsigned int scriptPubKeyLen,
+                                                 const unsigned char *txTo        , unsigned int txToLen,
+                                                 unsigned int nIn, unsigned int flags, bitcoinconsensus_error* err);
+
+EXPORT_SYMBOL int bitcoinconsensus_verify_script_with_amount(const unsigned char *scriptPubKey, unsigned int scriptPubKeyLen, int64_t amount,
                                     const unsigned char *txTo        , unsigned int txToLen,
                                     unsigned int nIn, unsigned int flags, bitcoinconsensus_error* err);
 

src/test/script_tests.cpp

@@ -160,7 +160,12 @@ void DoTest(const CScript& scriptPubKey, const CScript& scriptSig, int flags, co
 #if defined(HAVE_CONSENSUS_LIB)
     CDataStream stream(SER_NETWORK, PROTOCOL_VERSION);
     stream << tx2;
-    BOOST_CHECK_MESSAGE(bitcoinconsensus_verify_script(begin_ptr(scriptPubKey), scriptPubKey.size(), (const unsigned char*)&stream[0], stream.size(), 0, flags, NULL) == expect,message);
+    if (flags & bitcoinconsensus_SCRIPT_FLAGS_VERIFY_WITNESS) {
+        BOOST_CHECK_MESSAGE(bitcoinconsensus_verify_script_with_amount(begin_ptr(scriptPubKey), scriptPubKey.size(), amountZero, (const unsigned char*)&stream[0], stream.size(), 0, flags, NULL) == expect, message);
+    } else {
+        BOOST_CHECK_MESSAGE(bitcoinconsensus_verify_script_with_amount(begin_ptr(scriptPubKey), scriptPubKey.size(), 0, (const unsigned char*)&stream[0], stream.size(), 0, flags, NULL) == expect, message);
+        BOOST_CHECK_MESSAGE(bitcoinconsensus_verify_script(begin_ptr(scriptPubKey), scriptPubKey.size(), (const unsigned char*)&stream[0], stream.size(), 0, flags, NULL) == expect,message);
+    }
 #endif
 }