text: // Copyright (c) 2012-2015 The Bitcoin Core developers
  // Distributed under the MIT software license, see the accompanying
  // file COPYING or http://www.opensource.org/licenses/mit-license.php.
  
  #include "core_io.h"
  #include "key.h"
  #include "keystore.h"
  #include "main.h"
  #include "policy/policy.h"
  #include "script/script.h"
  #include "script/script_error.h"
  #include "script/sign.h"
  #include "script/ismine.h"
  #include "test/test_devault.h"
  
  #include <vector>
  
  #include <boost/test/unit_test.hpp>
  
  using namespace std;
  
  // Helpers:
  static std::vector<unsigned char>
  Serialize(const CScript& s)
  {
      std::vector<unsigned char> sSerialized(s.begin(), s.end());
      return sSerialized;
  }
  
  static bool
  Verify(const CScript& scriptSig, const CScript& scriptPubKey, bool fStrict, ScriptError& err)
  {
      // Create dummy to/from transactions:
      CMutableTransaction txFrom;
      txFrom.vout.resize(1);
      txFrom.vout[0].scriptPubKey = scriptPubKey;
  
      CMutableTransaction txTo;
      txTo.vin.resize(1);
      txTo.vout.resize(1);
      txTo.vin[0].prevout.n = 0;
      txTo.vin[0].prevout.hash = txFrom.GetHash();
      txTo.vin[0].scriptSig = scriptSig;
      txTo.vout[0].nValue = 1;
  
      return VerifyScript(scriptSig, scriptPubKey, NULL, fStrict ? SCRIPT_VERIFY_P2SH : SCRIPT_VERIFY_NONE, MutableTransactionSignatureChecker(&txTo, 0, txFrom.vout[0].nValue), &err);
  }
  
  
  BOOST_FIXTURE_TEST_SUITE(script_P2SH_tests, BasicTestingSetup)
  
  BOOST_AUTO_TEST_CASE(sign)
  {
      LOCK(cs_main);
      // Pay-to-script-hash looks like this:
      // scriptSig:    <sig> <sig...> <serialized_script>
      // scriptPubKey: HASH160 <hash> EQUAL
  
      // Test SignSignature() (and therefore the version of Solver() that signs transactions)
      CBasicKeyStore keystore;
      CKey key[4];
      for (int i = 0; i < 4; i++)
      {
          key[i].MakeNewKey(true);
          keystore.AddKey(key[i]);
      }
  
      // 8 Scripts: checking all combinations of
      // different keys, straight/P2SH, pubkey/pubkeyhash
      CScript standardScripts[4];
      standardScripts[0] << ToByteVector(key[0].GetPubKey()) << OP_CHECKSIG;
      standardScripts[1] = GetScriptForDestination(key[1].GetPubKey().GetID());
      standardScripts[2] << ToByteVector(key[1].GetPubKey()) << OP_CHECKSIG;
      standardScripts[3] = GetScriptForDestination(key[2].GetPubKey().GetID());
      CScript evalScripts[4];
      for (int i = 0; i < 4; i++)
      {
          keystore.AddCScript(standardScripts[i]);
          evalScripts[i] = GetScriptForDestination(CScriptID(standardScripts[i]));
      }
  
      CMutableTransaction txFrom;  // Funding transaction:
      string reason;
      txFrom.vout.resize(8);
      for (int i = 0; i < 4; i++)
      {
          txFrom.vout[i].scriptPubKey = evalScripts[i];
          txFrom.vout[i].nValue = COIN;
          txFrom.vout[i+4].scriptPubKey = standardScripts[i];
          txFrom.vout[i+4].nValue = COIN;
      }
      BOOST_CHECK(IsStandardTx(txFrom, reason));
  
      CMutableTransaction txTo[8]; // Spending transactions
      for (int i = 0; i < 8; i++)
      {
          txTo[i].vin.resize(1);
          txTo[i].vout.resize(1);
          txTo[i].vin[0].prevout.n = i;
          txTo[i].vin[0].prevout.hash = txFrom.GetHash();
          txTo[i].vout[0].nValue = 1;
          BOOST_CHECK_MESSAGE(IsMine(keystore, txFrom.vout[i].scriptPubKey), strprintf("IsMine %d", i));
      }
      for (int i = 0; i < 8; i++)
      {
          BOOST_CHECK_MESSAGE(SignSignature(keystore, txFrom, txTo[i], 0, SIGHASH_ALL), strprintf("SignSignature %d", i));
      }
      // All of the above should be OK, and the txTos have valid signatures
      // Check to make sure signature verification fails if we use the wrong ScriptSig:
  
      for (int i = 0; i < 8; i++)
          for (int j = 0; j < 8; j++)
          {
              PrecomputedTransactionData txdata(txTo[i]);
              CScript sigSave = txTo[i].vin[0].scriptSig;
              txTo[i].vin[0].scriptSig = txTo[j].vin[0].scriptSig;
              bool sigOK = CScriptCheck(CCoins(txFrom, 0), txTo[i], 0, SCRIPT_VERIFY_P2SH | SCRIPT_VERIFY_STRICTENC, false, &txdata)();
              if (i == j)
                  BOOST_CHECK_MESSAGE(sigOK, strprintf("VerifySignature %d %d", i, j));
              else
                  BOOST_CHECK_MESSAGE(!sigOK, strprintf("VerifySignature %d %d", i, j));
              txTo[i].vin[0].scriptSig = sigSave;
          }
  }
  
  BOOST_AUTO_TEST_CASE(norecurse)
  {
      ScriptError err;
      // Make sure only the outer pay-to-script-hash does the
      // extra-validation thing:
      CScript invalidAsScript;
      invalidAsScript << OP_INVALIDOPCODE << OP_INVALIDOPCODE;
  
      CScript p2sh = GetScriptForDestination(CScriptID(invalidAsScript));
  
      CScript scriptSig;
      scriptSig << Serialize(invalidAsScript);
  
      // Should not verify, because it will try to execute OP_INVALIDOPCODE
      BOOST_CHECK(!Verify(scriptSig, p2sh, true, err));
      BOOST_CHECK_MESSAGE(err == SCRIPT_ERR_BAD_OPCODE, ScriptErrorString(err));
  
      // Try to recur, and verification should succeed because
      // the inner HASH160 <> EQUAL should only check the hash:
      CScript p2sh2 = GetScriptForDestination(CScriptID(p2sh));
      CScript scriptSig2;
      scriptSig2 << Serialize(invalidAsScript) << Serialize(p2sh);
  
      BOOST_CHECK(Verify(scriptSig2, p2sh2, true, err));
      BOOST_CHECK_MESSAGE(err == SCRIPT_ERR_OK, ScriptErrorString(err));
  }
  
  BOOST_AUTO_TEST_CASE(set)
  {
      LOCK(cs_main);
      // Test the CScript::Set* methods
      CBasicKeyStore keystore;
      CKey key[4];
      std::vector<CPubKey> keys;
      for (int i = 0; i < 4; i++)
      {
          key[i].MakeNewKey(true);
          keystore.AddKey(key[i]);
          keys.push_back(key[i].GetPubKey());
      }
  
      CScript inner[4];
      inner[0] = GetScriptForDestination(key[0].GetPubKey().GetID());
      inner[1] = GetScriptForMultisig(2, std::vector<CPubKey>(keys.begin(), keys.begin()+2));
      inner[2] = GetScriptForMultisig(1, std::vector<CPubKey>(keys.begin(), keys.begin()+2));
      inner[3] = GetScriptForMultisig(2, std::vector<CPubKey>(keys.begin(), keys.begin()+3));
  
      CScript outer[4];
      for (int i = 0; i < 4; i++)
      {
          outer[i] = GetScriptForDestination(CScriptID(inner[i]));
          keystore.AddCScript(inner[i]);
      }
  
      CMutableTransaction txFrom;  // Funding transaction:
      string reason;
      txFrom.vout.resize(4);
      for (int i = 0; i < 4; i++)
      {
          txFrom.vout[i].scriptPubKey = outer[i];
          txFrom.vout[i].nValue = CENT;
      }
      BOOST_CHECK(IsStandardTx(txFrom, reason));
  
      CMutableTransaction txTo[4]; // Spending transactions
      for (int i = 0; i < 4; i++)
      {
          txTo[i].vin.resize(1);
          txTo[i].vout.resize(1);
          txTo[i].vin[0].prevout.n = i;
          txTo[i].vin[0].prevout.hash = txFrom.GetHash();
          txTo[i].vout[0].nValue = 1*CENT;
          txTo[i].vout[0].scriptPubKey = inner[i];
          BOOST_CHECK_MESSAGE(IsMine(keystore, txFrom.vout[i].scriptPubKey), strprintf("IsMine %d", i));
      }
      for (int i = 0; i < 4; i++)
      {
          BOOST_CHECK_MESSAGE(SignSignature(keystore, txFrom, txTo[i], 0, SIGHASH_ALL), strprintf("SignSignature %d", i));
          BOOST_CHECK_MESSAGE(IsStandardTx(txTo[i], reason), strprintf("txTo[%d].IsStandard", i));
      }
  }
  
  BOOST_AUTO_TEST_CASE(is)
  {
      // Test CScript::IsPayToScriptHash()
      uint160 dummy;
      CScript p2sh;
      p2sh << OP_HASH160 << ToByteVector(dummy) << OP_EQUAL;
      BOOST_CHECK(p2sh.IsPayToScriptHash());
  
      // Not considered pay-to-script-hash if using one of the OP_PUSHDATA opcodes:
      static const unsigned char direct[] =    { OP_HASH160, 20, 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, OP_EQUAL };
      BOOST_CHECK(CScript(direct, direct+sizeof(direct)).IsPayToScriptHash());
      static const unsigned char pushdata1[] = { OP_HASH160, OP_PUSHDATA1, 20, 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, OP_EQUAL };
      BOOST_CHECK(!CScript(pushdata1, pushdata1+sizeof(pushdata1)).IsPayToScriptHash());
      static const unsigned char pushdata2[] = { OP_HASH160, OP_PUSHDATA2, 20,0, 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, OP_EQUAL };
      BOOST_CHECK(!CScript(pushdata2, pushdata2+sizeof(pushdata2)).IsPayToScriptHash());
      static const unsigned char pushdata4[] = { OP_HASH160, OP_PUSHDATA4, 20,0,0,0, 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, OP_EQUAL };
      BOOST_CHECK(!CScript(pushdata4, pushdata4+sizeof(pushdata4)).IsPayToScriptHash());
  
      CScript not_p2sh;
      BOOST_CHECK(!not_p2sh.IsPayToScriptHash());
  
      not_p2sh.clear(); not_p2sh << OP_HASH160 << ToByteVector(dummy) << ToByteVector(dummy) << OP_EQUAL;
      BOOST_CHECK(!not_p2sh.IsPayToScriptHash());
  
      not_p2sh.clear(); not_p2sh << OP_NOP << ToByteVector(dummy) << OP_EQUAL;
      BOOST_CHECK(!not_p2sh.IsPayToScriptHash());
  
      not_p2sh.clear(); not_p2sh << OP_HASH160 << ToByteVector(dummy) << OP_CHECKSIG;
      BOOST_CHECK(!not_p2sh.IsPayToScriptHash());
  }
  
  BOOST_AUTO_TEST_CASE(switchover)
  {
      // Test switch over code
      CScript notValid;
      ScriptError err;
      notValid << OP_11 << OP_12 << OP_EQUALVERIFY;
      CScript scriptSig;
      scriptSig << Serialize(notValid);
  
      CScript fund = GetScriptForDestination(CScriptID(notValid));
  
  
      // Validation should succeed under old rules (hash is correct):
      BOOST_CHECK(Verify(scriptSig, fund, false, err));
      BOOST_CHECK_MESSAGE(err == SCRIPT_ERR_OK, ScriptErrorString(err));
      // Fail under new:
      BOOST_CHECK(!Verify(scriptSig, fund, true, err));
      BOOST_CHECK_MESSAGE(err == SCRIPT_ERR_EQUALVERIFY, ScriptErrorString(err));
  }
  
  BOOST_AUTO_TEST_CASE(AreInputsStandard)
  {
      LOCK(cs_main);
      CCoinsView coinsDummy;
      CCoinsViewCache coins(&coinsDummy);
      CBasicKeyStore keystore;
      CKey key[6];
      vector<CPubKey> keys;
      for (int i = 0; i < 6; i++)
      {
          key[i].MakeNewKey(true);
          keystore.AddKey(key[i]);
      }
      for (int i = 0; i < 3; i++)
          keys.push_back(key[i].GetPubKey());
  
      CMutableTransaction txFrom;
      txFrom.vout.resize(7);
  
      // First three are standard:
      CScript pay1 = GetScriptForDestination(key[0].GetPubKey().GetID());
      keystore.AddCScript(pay1);
      CScript pay1of3 = GetScriptForMultisig(1, keys);
  
      txFrom.vout[0].scriptPubKey = GetScriptForDestination(CScriptID(pay1)); // P2SH (OP_CHECKSIG)
      txFrom.vout[0].nValue = 1000;
      txFrom.vout[1].scriptPubKey = pay1; // ordinary OP_CHECKSIG
      txFrom.vout[1].nValue = 2000;
      txFrom.vout[2].scriptPubKey = pay1of3; // ordinary OP_CHECKMULTISIG
      txFrom.vout[2].nValue = 3000;
  
      // vout[3] is complicated 1-of-3 AND 2-of-3
      // ... that is OK if wrapped in P2SH:
      CScript oneAndTwo;
      oneAndTwo << OP_1 << ToByteVector(key[0].GetPubKey()) << ToByteVector(key[1].GetPubKey()) << ToByteVector(key[2].GetPubKey());
      oneAndTwo << OP_3 << OP_CHECKMULTISIGVERIFY;
      oneAndTwo << OP_2 << ToByteVector(key[3].GetPubKey()) << ToByteVector(key[4].GetPubKey()) << ToByteVector(key[5].GetPubKey());
      oneAndTwo << OP_3 << OP_CHECKMULTISIG;
      keystore.AddCScript(oneAndTwo);
      txFrom.vout[3].scriptPubKey = GetScriptForDestination(CScriptID(oneAndTwo));
      txFrom.vout[3].nValue = 4000;
  
      // vout[4] is max sigops:
      CScript fifteenSigops; fifteenSigops << OP_1;
      for (unsigned i = 0; i < MAX_P2SH_SIGOPS; i++)
          fifteenSigops << ToByteVector(key[i%3].GetPubKey());
      fifteenSigops << OP_15 << OP_CHECKMULTISIG;
      keystore.AddCScript(fifteenSigops);
      txFrom.vout[4].scriptPubKey = GetScriptForDestination(CScriptID(fifteenSigops));
      txFrom.vout[4].nValue = 5000;
  
      // vout[5/6] are non-standard because they exceed MAX_P2SH_SIGOPS
      CScript sixteenSigops; sixteenSigops << OP_16 << OP_CHECKMULTISIG;
      keystore.AddCScript(sixteenSigops);
      txFrom.vout[5].scriptPubKey = GetScriptForDestination(CScriptID(fifteenSigops));
      txFrom.vout[5].nValue = 5000;
      CScript twentySigops; twentySigops << OP_CHECKMULTISIG;
      keystore.AddCScript(twentySigops);
      txFrom.vout[6].scriptPubKey = GetScriptForDestination(CScriptID(twentySigops));
      txFrom.vout[6].nValue = 6000;
  
      coins.ModifyCoins(txFrom.GetHash())->FromTx(txFrom, 0);
  
      CMutableTransaction txTo;
      txTo.vout.resize(1);
      txTo.vout[0].scriptPubKey = GetScriptForDestination(key[1].GetPubKey().GetID());
  
      txTo.vin.resize(5);
      for (int i = 0; i < 5; i++)
      {
          txTo.vin[i].prevout.n = i;
          txTo.vin[i].prevout.hash = txFrom.GetHash();
      }
      BOOST_CHECK(SignSignature(keystore, txFrom, txTo, 0, SIGHASH_ALL));
      BOOST_CHECK(SignSignature(keystore, txFrom, txTo, 1, SIGHASH_ALL));
      BOOST_CHECK(SignSignature(keystore, txFrom, txTo, 2, SIGHASH_ALL));
      // SignSignature doesn't know how to sign these. We're
      // not testing validating signatures, so just create
      // dummy signatures that DO include the correct P2SH scripts:
      txTo.vin[3].scriptSig << OP_11 << OP_11 << vector<unsigned char>(oneAndTwo.begin(), oneAndTwo.end());
      txTo.vin[4].scriptSig << vector<unsigned char>(fifteenSigops.begin(), fifteenSigops.end());
  
      BOOST_CHECK(::AreInputsStandard(txTo, coins));
      // 22 P2SH sigops for all inputs (1 for vin[0], 6 for vin[3], 15 for vin[4]
      BOOST_CHECK_EQUAL(GetP2SHSigOpCount(txTo, coins), 22U);
  
      CMutableTransaction txToNonStd1;
      txToNonStd1.vout.resize(1);
      txToNonStd1.vout[0].scriptPubKey = GetScriptForDestination(key[1].GetPubKey().GetID());
      txToNonStd1.vout[0].nValue = 1000;
      txToNonStd1.vin.resize(1);
      txToNonStd1.vin[0].prevout.n = 5;
      txToNonStd1.vin[0].prevout.hash = txFrom.GetHash();
      txToNonStd1.vin[0].scriptSig << vector<unsigned char>(sixteenSigops.begin(), sixteenSigops.end());
  
      BOOST_CHECK(!::AreInputsStandard(txToNonStd1, coins));
      BOOST_CHECK_EQUAL(GetP2SHSigOpCount(txToNonStd1, coins), 16U);
  
      CMutableTransaction txToNonStd2;
      txToNonStd2.vout.resize(1);
      txToNonStd2.vout[0].scriptPubKey = GetScriptForDestination(key[1].GetPubKey().GetID());
      txToNonStd2.vout[0].nValue = 1000;
      txToNonStd2.vin.resize(1);
      txToNonStd2.vin[0].prevout.n = 6;
      txToNonStd2.vin[0].prevout.hash = txFrom.GetHash();
      txToNonStd2.vin[0].scriptSig << vector<unsigned char>(twentySigops.begin(), twentySigops.end());
  
      BOOST_CHECK(!::AreInputsStandard(txToNonStd2, coins));
      BOOST_CHECK_EQUAL(GetP2SHSigOpCount(txToNonStd2, coins), 20U);
  }
  
  BOOST_AUTO_TEST_SUITE_END()
  