From 46d1bcc607ee5b795ed72351b24f978ab6952633 Mon Sep 17 00:00:00 2001
From: Scott Sadler <scott@alphanode.co>
Date: Thu, 22 Feb 2018 01:43:43 -0300
Subject: [PATCH] integration test for complex aux condition

---
 qa/cryptoconditions/test_integration.py | 44 +++++++++++++++++++++++++
 src/komodo_cryptoconditions.cpp         | 13 +++++++-
 src/script/interpreter.cpp              |  2 +-
 src/script/interpreter.h                |  7 +---
 4 files changed, 58 insertions(+), 8 deletions(-)

diff --git a/qa/cryptoconditions/test_integration.py b/qa/cryptoconditions/test_integration.py
index d5b456953..6d60ee921 100644
--- a/qa/cryptoconditions/test_integration.py
+++ b/qa/cryptoconditions/test_integration.py
@@ -127,6 +127,50 @@ def test_aux_basic(inp):
         assert 'Script evaluated without error but finished with a false/empty top stack element' in str(e), str(e)
 
 
+@fanout_input(7)
+def test_aux_complex(inp):
+    aux_cond = {
+        'type': 'aux-sha-256',
+        'method': 'inputIsReturn',
+        'conditionAux': '',
+        'fulfillmentAux': 'AQ' # \1 (tx.vout[1])
+    }
+
+    # Setup some aux outputs
+    spend0 = {
+        'inputs': [inp],
+        'outputs': [
+            {'amount': 500, 'script': {'condition': aux_cond}},
+            {'amount': 500, 'script': {'condition': aux_cond}}
+        ]
+    }
+    spend0_txid = submit(sign(spend0))
+    assert rpc.getrawtransaction(spend0_txid)
+
+    # Test a good fulfillment
+    spend1 = {
+        'inputs': [{'txid': spend0_txid, 'idx': 0, 'script': {'fulfillment': aux_cond}}],
+        'outputs': [
+            {'amount': 250, 'script': {'condition': aux_cond}},
+            {'amount': 250, 'script': "6A0B68656C6C6F207468657265"} # OP_RETURN somedata
+        ]
+    }
+    spend1_txid = submit(sign(spend1))
+    assert rpc.getrawtransaction(spend1_txid)
+
+    # Test a bad fulfillment
+    spend2 = {
+        'inputs': [{'txid': spend0_txid, 'idx': 1, 'script': {'fulfillment': aux_cond}}],
+        'outputs': [
+            {'amount': 500, 'script': "6A0B68656C6C6F207468657265"} # OP_RETURN somedata
+        ]
+    }
+    try:
+        assert not submit(sign(spend2)), 'should raise an error'
+    except RPCError as e:
+        assert 'Script evaluated without error but finished with a false/empty top stack element' in str(e), str(e)
+
+
 if __name__ == '__main__':
     logging.basicConfig(level=logging.INFO)
     for name, f in globals().items():
diff --git a/src/komodo_cryptoconditions.cpp b/src/komodo_cryptoconditions.cpp
index 9617add50..c807df7c9 100644
--- a/src/komodo_cryptoconditions.cpp
+++ b/src/komodo_cryptoconditions.cpp
@@ -3,11 +3,22 @@
 #include "script/interpreter.h"
 
 
-int CryptoConditionChecker::CheckAuxCondition(const CC *cond) const {
+int TransactionSignatureChecker::CheckAuxCondition(const CC *cond) const {
+
+    // Check that condition is equal to fulfillment
     if (0 == strcmp((const char*)cond->method, "equals")) {
         return (cond->conditionAuxLength == cond->fulfillmentAuxLength) &&
                (0 == memcmp(cond->conditionAux, cond->fulfillmentAux, cond->conditionAuxLength));
     }
+
+    // Check that pubKeyScript specified in fulfillment is OP_RETURN
+    if (0 == strcmp((const char*)cond->method, "inputIsReturn")) {
+        if (cond->fulfillmentAuxLength != 1) return 0;
+        int n = (int) cond->fulfillmentAux[0];
+        if (n >= txTo->vout.size()) return 0;
+        uint8_t *ptr = (uint8_t *)txTo->vout[n].scriptPubKey.data();
+        return ptr[0] == OP_RETURN;
+    }
     printf("no defined behaviour for method:%s\n", cond->method);
     return 0;
 }
diff --git a/src/script/interpreter.cpp b/src/script/interpreter.cpp
index 689dcf204..709b566f6 100644
--- a/src/script/interpreter.cpp
+++ b/src/script/interpreter.cpp
@@ -1158,7 +1158,7 @@ extern "C"
 }
 
 static int komodoCCAux(CC *cond, void *checker) {
-    return ((CryptoConditionChecker*)checker)->CheckAuxCondition(cond);
+    return ((TransactionSignatureChecker*)checker)->CheckAuxCondition(cond);
 }
 
 bool TransactionSignatureChecker::CheckCryptoCondition(const CC *cond, const std::vector<unsigned char>& condBin, const CScript& scriptCode) const
diff --git a/src/script/interpreter.h b/src/script/interpreter.h
index 90c50eff6..8936fde7a 100644
--- a/src/script/interpreter.h
+++ b/src/script/interpreter.h
@@ -125,6 +125,7 @@ public:
     bool CheckSig(const std::vector<unsigned char>& scriptSig, const std::vector<unsigned char>& vchPubKey, const CScript& scriptCode) const;
     bool CheckLockTime(const CScriptNum& nLockTime) const;
     bool CheckCryptoCondition(const CC *cond, const std::vector<unsigned char>& condBin, const CScript& scriptCode) const;
+    int CheckAuxCondition(const CC *cond) const;
 };
 
 class MutableTransactionSignatureChecker : public TransactionSignatureChecker
@@ -139,10 +140,4 @@ public:
 bool EvalScript(std::vector<std::vector<unsigned char> >& stack, const CScript& script, unsigned int flags, const BaseSignatureChecker& checker, ScriptError* error = NULL);
 bool VerifyScript(const CScript& scriptSig, const CScript& scriptPubKey, unsigned int flags, const BaseSignatureChecker& checker, ScriptError* error = NULL);
 
-class CryptoConditionChecker : public TransactionSignatureChecker
-{
-public:
-    int CheckAuxCondition(const CC *cond) const;
-};
-
 #endif // BITCOIN_SCRIPT_INTERPRETER_H