BIP143: Verification logic

Includes simplifications by Eric Lombrozo.

Edited for Zcash merge by Ariel Gabizon.
This commit is contained in:
Pieter Wuille
2017-12-15 16:38:34 +01:00
committed by Jack Grigg
parent 2d42e1a993
commit c86a1cb86e
16 changed files with 137 additions and 69 deletions

View File

@@ -232,7 +232,7 @@ bool static CheckMinimalPush(const valtype& data, opcodetype opcode) {
return true;
}
bool EvalScript(vector<vector<unsigned char> >& stack, const CScript& script, unsigned int flags, const BaseSignatureChecker& checker, ScriptError* serror)
bool EvalScript(vector<vector<unsigned char> >& stack, const CScript& script, unsigned int flags, const BaseSignatureChecker& checker, SigVersion sigversion, ScriptError* serror)
{
static const CScriptNum bnZero(0);
static const CScriptNum bnOne(1);
@@ -828,7 +828,7 @@ bool EvalScript(vector<vector<unsigned char> >& stack, const CScript& script, un
//serror is set
return false;
}
bool fSuccess = checker.CheckSig(vchSig, vchPubKey, script);
bool fSuccess = checker.CheckSig(vchSig, vchPubKey, script, sigversion);
popstack(stack);
popstack(stack);
@@ -886,7 +886,7 @@ bool EvalScript(vector<vector<unsigned char> >& stack, const CScript& script, un
}
// Check signature
bool fOk = checker.CheckSig(vchSig, vchPubKey, script);
bool fOk = checker.CheckSig(vchSig, vchPubKey, script, sigversion);
if (fOk) {
isig++;
@@ -1052,13 +1052,71 @@ public:
} // anon namespace
uint256 SignatureHash(const CScript& scriptCode, const CTransaction& txTo, unsigned int nIn, int nHashType)
uint256 SignatureHash(const CScript& scriptCode, const CTransaction& txTo, unsigned int nIn, int nHashType, const CAmount& amount, SigVersion sigversion)
{
if (nIn >= txTo.vin.size() && nIn != NOT_AN_INPUT) {
// nIn out of range
throw logic_error("input index is out of range");
}
if (sigversion == SIGVERSION_WITNESS_V0) {
uint256 hashPrevouts;
uint256 hashSequence;
uint256 hashOutputs;
if (!(nHashType & SIGHASH_ANYONECANPAY)) {
CHashWriter ss(SER_GETHASH, 0);
for (unsigned int n = 0; n < txTo.vin.size(); n++) {
ss << txTo.vin[n].prevout;
}
hashPrevouts = ss.GetHash(); // TODO: cache this value for all signatures in a transaction
}
if (!(nHashType & SIGHASH_ANYONECANPAY) && (nHashType & 0x1f) != SIGHASH_SINGLE && (nHashType & 0x1f) != SIGHASH_NONE) {
CHashWriter ss(SER_GETHASH, 0);
for (unsigned int n = 0; n < txTo.vin.size(); n++) {
ss << txTo.vin[n].nSequence;
}
hashSequence = ss.GetHash(); // TODO: cache this value for all signatures in a transaction
}
if ((nHashType & 0x1f) != SIGHASH_SINGLE && (nHashType & 0x1f) != SIGHASH_NONE) {
CHashWriter ss(SER_GETHASH, 0);
for (unsigned int n = 0; n < txTo.vout.size(); n++) {
ss << txTo.vout[n];
}
hashOutputs = ss.GetHash(); // TODO: cache this value for all signatures in a transaction
} else if ((nHashType & 0x1f) == SIGHASH_SINGLE && nIn < txTo.vout.size()) {
CHashWriter ss(SER_GETHASH, 0);
ss << txTo.vout[nIn];
hashOutputs = ss.GetHash();
}
CHashWriter ss(SER_GETHASH, 0);
// Version
ss << txTo.nVersion;
// Input prevouts/nSequence (none/all, depending on flags)
ss << hashPrevouts;
ss << hashSequence;
// The input being signed (replacing the scriptSig with scriptCode + amount)
// The prevout may already be contained in hashPrevout, and the nSequence
// may already be contained in hashSequence.
if (nIn != NOT_AN_INPUT)
ss << txTo.vin[nIn].prevout;
ss << scriptCode;
ss << amount;
if (nIn != NOT_AN_INPUT)
ss << txTo.vin[nIn].nSequence;
// Outputs (none/one/all, depending on flags)
ss << hashOutputs;
// Locktime
ss << txTo.nLockTime;
// Sighash type
ss << nHashType;
return ss.GetHash();
}
// Check for invalid use of SIGHASH_SINGLE
if ((nHashType & 0x1f) == SIGHASH_SINGLE) {
if (nIn >= txTo.vout.size()) {
@@ -1081,7 +1139,7 @@ bool TransactionSignatureChecker::VerifySignature(const std::vector<unsigned cha
return pubkey.Verify(sighash, vchSig);
}
bool TransactionSignatureChecker::CheckSig(const vector<unsigned char>& vchSigIn, const vector<unsigned char>& vchPubKey, const CScript& scriptCode) const
bool TransactionSignatureChecker::CheckSig(const vector<unsigned char>& vchSigIn, const vector<unsigned char>& vchPubKey, const CScript& scriptCode, SigVersion sigversion) const
{
CPubKey pubkey(vchPubKey);
if (!pubkey.IsValid())
@@ -1096,7 +1154,7 @@ bool TransactionSignatureChecker::CheckSig(const vector<unsigned char>& vchSigIn
uint256 sighash;
try {
sighash = SignatureHash(scriptCode, *txTo, nIn, nHashType);
sighash = SignatureHash(scriptCode, *txTo, nIn, nHashType, amount, sigversion);
} catch (logic_error ex) {
return false;
}
@@ -1153,12 +1211,12 @@ bool VerifyScript(const CScript& scriptSig, const CScript& scriptPubKey, unsigne
}
vector<vector<unsigned char> > stack, stackCopy;
if (!EvalScript(stack, scriptSig, flags, checker, serror))
if (!EvalScript(stack, scriptSig, flags, checker, SIGVERSION_BASE, serror))
// serror is set
return false;
if (flags & SCRIPT_VERIFY_P2SH)
stackCopy = stack;
if (!EvalScript(stack, scriptPubKey, flags, checker, serror))
if (!EvalScript(stack, scriptPubKey, flags, checker, SIGVERSION_BASE, serror))
// serror is set
return false;
if (stack.empty())
@@ -1185,7 +1243,7 @@ bool VerifyScript(const CScript& scriptSig, const CScript& scriptPubKey, unsigne
CScript pubKey2(pubKeySerialized.begin(), pubKeySerialized.end());
popstack(stack);
if (!EvalScript(stack, pubKey2, flags, checker, serror))
if (!EvalScript(stack, pubKey2, flags, checker, SIGVERSION_BASE, serror))
// serror is set
return false;
if (stack.empty())

View File

@@ -88,12 +88,18 @@ enum
SCRIPT_VERIFY_CHECKLOCKTIMEVERIFY = (1U << 9),
};
uint256 SignatureHash(const CScript &scriptCode, const CTransaction& txTo, unsigned int nIn, int nHashType);
enum SigVersion
{
SIGVERSION_BASE = 0,
SIGVERSION_WITNESS_V0 = 1,
};
uint256 SignatureHash(const CScript &scriptCode, const CTransaction& txTo, unsigned int nIn, int nHashType, const CAmount& amount, SigVersion sigversion);
class BaseSignatureChecker
{
public:
virtual bool CheckSig(const std::vector<unsigned char>& scriptSig, const std::vector<unsigned char>& vchPubKey, const CScript& scriptCode) const
virtual bool CheckSig(const std::vector<unsigned char>& scriptSig, const std::vector<unsigned char>& vchPubKey, const CScript& scriptCode, SigVersion sigversion) const
{
return false;
}
@@ -111,13 +117,14 @@ class TransactionSignatureChecker : public BaseSignatureChecker
private:
const CTransaction* txTo;
unsigned int nIn;
const CAmount amount;
protected:
virtual bool VerifySignature(const std::vector<unsigned char>& vchSig, const CPubKey& vchPubKey, const uint256& sighash) const;
public:
TransactionSignatureChecker(const CTransaction* txToIn, unsigned int nInIn, const CAmount& amount) : txTo(txToIn), nIn(nInIn) {}
bool CheckSig(const std::vector<unsigned char>& scriptSig, const std::vector<unsigned char>& vchPubKey, const CScript& scriptCode) const;
TransactionSignatureChecker(const CTransaction* txToIn, unsigned int nInIn, const CAmount& amountIn) : txTo(txToIn), nIn(nInIn), amount(amountIn) {}
bool CheckSig(const std::vector<unsigned char>& scriptSig, const std::vector<unsigned char>& vchPubKey, const CScript& scriptCode, SigVersion sigversion) const;
bool CheckLockTime(const CScriptNum& nLockTime) const;
};
@@ -130,7 +137,7 @@ public:
MutableTransactionSignatureChecker(const CMutableTransaction* txToIn, unsigned int nInIn, const CAmount& amount) : TransactionSignatureChecker(&txTo, nInIn, amount), txTo(*txToIn) {}
};
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);
bool EvalScript(std::vector<std::vector<unsigned char> >& stack, const CScript& script, unsigned int flags, const BaseSignatureChecker& checker, SigVersion sigversion, ScriptError* error = NULL);
bool VerifyScript(const CScript& scriptSig, const CScript& scriptPubKey, unsigned int flags, const BaseSignatureChecker& checker, ScriptError* serror = NULL);
#endif // BITCOIN_SCRIPT_INTERPRETER_H

View File

@@ -17,8 +17,7 @@ using namespace std;
typedef vector<unsigned char> valtype;
static const CAmount amountZero = 0;
TransactionSignatureCreator::TransactionSignatureCreator(const CKeyStore* keystoreIn, const CTransaction* txToIn, unsigned int nInIn, int nHashTypeIn) : BaseSignatureCreator(keystoreIn), txTo(txToIn), nIn(nInIn), nHashType(nHashTypeIn), checker(txTo, nIn, amountZero) {}
TransactionSignatureCreator::TransactionSignatureCreator(const CKeyStore* keystoreIn, const CTransaction* txToIn, unsigned int nInIn, const CAmount& amountIn, int nHashTypeIn) : BaseSignatureCreator(keystoreIn), txTo(txToIn), nIn(nInIn), nHashType(nHashTypeIn), amount(amountIn), checker(txTo, nIn, amountIn) {}
bool TransactionSignatureCreator::CreateSig(std::vector<unsigned char>& vchSig, const CKeyID& address, const CScript& scriptCode) const
{
@@ -28,7 +27,7 @@ bool TransactionSignatureCreator::CreateSig(std::vector<unsigned char>& vchSig,
uint256 hash;
try {
hash = SignatureHash(scriptCode, *txTo, nIn, nHashType);
hash = SignatureHash(scriptCode, *txTo, nIn, nHashType, amount, SIGVERSION_BASE);
} catch (logic_error ex) {
return false;
}
@@ -191,7 +190,7 @@ static CScript CombineMultisig(const CScript& scriptPubKey, const BaseSignatureC
if (sigs.count(pubkey))
continue; // Already got a sig for this pubkey
if (checker.CheckSig(sig, pubkey, scriptPubKey))
if (checker.CheckSig(sig, pubkey, scriptPubKey, SIGVERSION_BASE))
{
sigs[pubkey] = sig;
break;
@@ -261,10 +260,10 @@ static CScript CombineSignatures(const CScript& scriptPubKey, const BaseSignatur
return CScript();
}
CScript CombineSignatures(const CScript& scriptPubKey, const CTransaction& txTo, unsigned int nIn,
CScript CombineSignatures(const CScript& scriptPubKey, const CTransaction& txTo, unsigned int nIn, const CAmount& amount,
const CScript& scriptSig1, const CScript& scriptSig2)
{
TransactionSignatureChecker checker(&txTo, nIn, amountZero);
TransactionSignatureChecker checker(&txTo, nIn, amount);
return CombineSignatures(scriptPubKey, checker, scriptSig1, scriptSig2);
}
@@ -276,9 +275,9 @@ CScript CombineSignatures(const CScript& scriptPubKey, const BaseSignatureChecke
Solver(scriptPubKey, txType, vSolutions);
vector<valtype> stack1;
EvalScript(stack1, scriptSig1, SCRIPT_VERIFY_STRICTENC, BaseSignatureChecker());
EvalScript(stack1, scriptSig1, SCRIPT_VERIFY_STRICTENC, BaseSignatureChecker(), SIGVERSION_BASE);
vector<valtype> stack2;
EvalScript(stack2, scriptSig2, SCRIPT_VERIFY_STRICTENC, BaseSignatureChecker());
EvalScript(stack2, scriptSig2, SCRIPT_VERIFY_STRICTENC, BaseSignatureChecker(), SIGVERSION_BASE);
return CombineSignatures(scriptPubKey, checker, txType, vSolutions, stack1, stack2);
}
@@ -290,7 +289,7 @@ class DummySignatureChecker : public BaseSignatureChecker
public:
DummySignatureChecker() {}
bool CheckSig(const std::vector<unsigned char>& scriptSig, const std::vector<unsigned char>& vchPubKey, const CScript& scriptCode) const
bool CheckSig(const std::vector<unsigned char>& scriptSig, const std::vector<unsigned char>& vchPubKey, const CScript& scriptCode, SigVersion sigversion) const
{
return true;
}

View File

@@ -35,10 +35,11 @@ class TransactionSignatureCreator : public BaseSignatureCreator {
const CTransaction* txTo;
unsigned int nIn;
int nHashType;
CAmount amount;
const TransactionSignatureChecker checker;
public:
TransactionSignatureCreator(const CKeyStore* keystoreIn, const CTransaction* txToIn, unsigned int nInIn, int nHashTypeIn=SIGHASH_ALL);
TransactionSignatureCreator(const CKeyStore* keystoreIn, const CTransaction* txToIn, unsigned int nInIn, const CAmount& amountIn, int nHashTypeIn=SIGHASH_ALL);
const BaseSignatureChecker& Checker() const { return checker; }
bool CreateSig(std::vector<unsigned char>& vchSig, const CKeyID& keyid, const CScript& scriptCode) const;
};
@@ -62,6 +63,6 @@ bool SignSignature(const CKeyStore& keystore, const CTransaction& txFrom, CMutab
CScript CombineSignatures(const CScript& scriptPubKey, const BaseSignatureChecker& checker, const CScript& scriptSig1, const CScript& scriptSig2);
/** Combine two script signatures on transactions. */
CScript CombineSignatures(const CScript& scriptPubKey, const CTransaction& txTo, unsigned int nIn, const CScript& scriptSig1, const CScript& scriptSig2);
CScript CombineSignatures(const CScript& scriptPubKey, const CTransaction& txTo, unsigned int nIn, const CAmount& amount, const CScript& scriptSig1, const CScript& scriptSig2);
#endif // BITCOIN_SCRIPT_SIGN_H