Merge #12714: Introduce interface for signing providers

d40f06a Introduce interface for signing providers (Pieter Wuille)

Pull request description:

  `CKeyStore` is a rich interface that provides many features, including knowledge of scripts and pubkeys for solving, private keys for signing, in addition to watch-only keys and scripts, and distinguishing lack of keys from them just being encrypted.

  The signing logic in script/sign does not actually need most of these features. Here we introduce a simpler interface (`SigningProvider`) which *only* provides keys and scripts. This is actually sufficient for signing.

  In addtion, we swap the dependency between keystore and script/sign (keystore now depends on script/script with `CKeyStore` deriving from `SigningProvider`, rather than `CKeyStore` being the interface that signing relies on).

  This is a very early step towards the design in https://gist.github.com/sipa/125cfa1615946d0c3f3eec2ad7f250a2, separating the concern between deciding what outputs are ours and signing.

Tree-SHA512: d511b7b03eec0e513530db1d9ae5aacf6d0bfa1d3e1c03d06c5bde396bafb5824c4491b227d32bcda9288530caf49835da18e846ccf66538d6c0cc6ae27291c9
This commit is contained in:
Wladimir J. van der Laan
2018-03-27 20:16:45 +02:00
3 changed files with 35 additions and 29 deletions

View File

@@ -6,7 +6,6 @@
#include <script/sign.h>
#include <key.h>
#include <keystore.h>
#include <policy/policy.h>
#include <primitives/transaction.h>
#include <script/standard.h>
@@ -15,12 +14,12 @@
typedef std::vector<unsigned char> valtype;
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) {}
TransactionSignatureCreator::TransactionSignatureCreator(const SigningProvider* provider, const CTransaction* txToIn, unsigned int nInIn, const CAmount& amountIn, int nHashTypeIn) : BaseSignatureCreator(provider), 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, SigVersion sigversion) const
{
CKey key;
if (!keystore->GetKey(address, key))
if (!m_provider->GetKey(address, key))
return false;
// Signing with uncompressed keys is disabled in witness scripts
@@ -91,12 +90,12 @@ static bool SignStep(const BaseSignatureCreator& creator, const CScript& scriptP
else
{
CPubKey vch;
creator.KeyStore().GetPubKey(keyID, vch);
creator.Provider().GetPubKey(keyID, vch);
ret.push_back(ToByteVector(vch));
}
return true;
case TX_SCRIPTHASH:
if (creator.KeyStore().GetCScript(uint160(vSolutions[0]), scriptRet)) {
if (creator.Provider().GetCScript(uint160(vSolutions[0]), scriptRet)) {
ret.push_back(std::vector<unsigned char>(scriptRet.begin(), scriptRet.end()));
return true;
}
@@ -112,7 +111,7 @@ static bool SignStep(const BaseSignatureCreator& creator, const CScript& scriptP
case TX_WITNESS_V0_SCRIPTHASH:
CRIPEMD160().Write(&vSolutions[0][0], vSolutions[0].size()).Finalize(h160.begin());
if (creator.KeyStore().GetCScript(h160, scriptRet)) {
if (creator.Provider().GetCScript(h160, scriptRet)) {
ret.push_back(std::vector<unsigned char>(scriptRet.begin(), scriptRet.end()));
return true;
}
@@ -206,12 +205,12 @@ void UpdateTransaction(CMutableTransaction& tx, unsigned int nIn, const Signatur
UpdateInput(tx.vin[nIn], data);
}
bool SignSignature(const CKeyStore &keystore, const CScript& fromPubKey, CMutableTransaction& txTo, unsigned int nIn, const CAmount& amount, int nHashType)
bool SignSignature(const SigningProvider &provider, const CScript& fromPubKey, CMutableTransaction& txTo, unsigned int nIn, const CAmount& amount, int nHashType)
{
assert(nIn < txTo.vin.size());
CTransaction txToConst(txTo);
TransactionSignatureCreator creator(&keystore, &txToConst, nIn, amount, nHashType);
TransactionSignatureCreator creator(&provider, &txToConst, nIn, amount, nHashType);
SignatureData sigdata;
bool ret = ProduceSignature(creator, fromPubKey, sigdata);
@@ -219,14 +218,14 @@ bool SignSignature(const CKeyStore &keystore, const CScript& fromPubKey, CMutabl
return ret;
}
bool SignSignature(const CKeyStore &keystore, const CTransaction& txFrom, CMutableTransaction& txTo, unsigned int nIn, int nHashType)
bool SignSignature(const SigningProvider &provider, const CTransaction& txFrom, CMutableTransaction& txTo, unsigned int nIn, int nHashType)
{
assert(nIn < txTo.vin.size());
CTxIn& txin = txTo.vin[nIn];
assert(txin.prevout.n < txFrom.vout.size());
const CTxOut& txout = txFrom.vout[txin.prevout.n];
return SignSignature(keystore, txout.scriptPubKey, txTo, nIn, txout.nValue, nHashType);
return SignSignature(provider, txout.scriptPubKey, txTo, nIn, txout.nValue, nHashType);
}
static std::vector<valtype> CombineMultisig(const CScript& scriptPubKey, const BaseSignatureChecker& checker,
@@ -427,13 +426,13 @@ bool DummySignatureCreator::CreateSig(std::vector<unsigned char>& vchSig, const
return true;
}
bool IsSolvable(const CKeyStore& store, const CScript& script)
bool IsSolvable(const SigningProvider& provider, const CScript& script)
{
// This check is to make sure that the script we created can actually be solved for and signed by us
// if we were to have the private keys. This is just to make sure that the script is valid and that,
// if found in a transaction, we would still accept and relay that transaction. In particular,
// it will reject witness outputs that require signing with an uncompressed public key.
DummySignatureCreator creator(&store);
DummySignatureCreator creator(&provider);
SignatureData sigs;
// Make sure that STANDARD_SCRIPT_VERIFY_FLAGS includes SCRIPT_VERIFY_WITNESS_PUBKEYTYPE, the most
// important property this function is designed to test for.