lbrycrd/src/script/sign.h
Andrew Chow 0422beb9bd Make SignatureData able to store signatures and scripts
In addition to having the scriptSig and scriptWitness, have SignatureData
also be able to store just the signatures (pubkeys mapped to sigs) and
scripts (script ids mapped to scripts).

Also have DataFromTransaction be able to extract signatures and scripts
from the scriptSig and scriptWitness of an input to put them in SignatureData.

Adds a new SignatureChecker which takes a SignatureData and puts pubkeys
and signatures into it when it successfully verifies a signature.

Adds a new field in SignatureData which stores whether the SignatureData
was complete. This allows us to also update the scriptSig and
scriptWitness to the final one when updating a SignatureData with another
one.
2018-07-03 17:18:52 -07:00

93 lines
4.7 KiB
C++

// Copyright (c) 2009-2010 Satoshi Nakamoto
// Copyright (c) 2009-2017 The Bitcoin Core developers
// Distributed under the MIT software license, see the accompanying
// file COPYING or http://www.opensource.org/licenses/mit-license.php.
#ifndef BITCOIN_SCRIPT_SIGN_H
#define BITCOIN_SCRIPT_SIGN_H
#include <script/interpreter.h>
class CKey;
class CKeyID;
class CScript;
class CScriptID;
class CTransaction;
struct CMutableTransaction;
/** An interface to be implemented by keystores that support signing. */
class SigningProvider
{
public:
virtual ~SigningProvider() {}
virtual bool GetCScript(const CScriptID &scriptid, CScript& script) const =0;
virtual bool GetPubKey(const CKeyID &address, CPubKey& pubkey) const =0;
virtual bool GetKey(const CKeyID &address, CKey& key) const =0;
};
/** Interface for signature creators. */
class BaseSignatureCreator {
public:
virtual ~BaseSignatureCreator() {}
virtual const BaseSignatureChecker& Checker() const =0;
/** Create a singular (non-script) signature. */
virtual bool CreateSig(const SigningProvider& provider, std::vector<unsigned char>& vchSig, const CKeyID& keyid, const CScript& scriptCode, SigVersion sigversion) const =0;
};
/** A signature creator for transactions. */
class MutableTransactionSignatureCreator : public BaseSignatureCreator {
const CMutableTransaction* txTo;
unsigned int nIn;
int nHashType;
CAmount amount;
const MutableTransactionSignatureChecker checker;
public:
MutableTransactionSignatureCreator(const CMutableTransaction* txToIn, unsigned int nInIn, const CAmount& amountIn, int nHashTypeIn = SIGHASH_ALL);
const BaseSignatureChecker& Checker() const override { return checker; }
bool CreateSig(const SigningProvider& provider, std::vector<unsigned char>& vchSig, const CKeyID& keyid, const CScript& scriptCode, SigVersion sigversion) const override;
};
/** A signature creator that just produces 72-byte empty signatures. */
extern const BaseSignatureCreator& DUMMY_SIGNATURE_CREATOR;
typedef std::pair<CPubKey, std::vector<unsigned char>> SigPair;
// This struct contains information from a transaction input and also contains signatures for that input.
// The information contained here can be used to create a signature and is also filled by ProduceSignature
// in order to construct final scriptSigs and scriptWitnesses.
struct SignatureData {
bool complete = false; ///< Stores whether the scriptSig and scriptWitness are complete
CScript scriptSig; ///< The scriptSig of an input. Contains complete signatures or the traditional partial signatures format
CScript redeem_script; ///< The redeemScript (if any) for the input
CScript witness_script; ///< The witnessScript (if any) for the input. witnessScripts are used in P2WSH outputs.
CScriptWitness scriptWitness; ///< The scriptWitness of an input. Contains complete signatures or the traditional partial signatures format. scriptWitness is part of a transaction input per BIP 144.
std::map<CKeyID, SigPair> signatures; ///< BIP 174 style partial signatures for the input. May contain all signatures necessary for producing a final scriptSig or scriptWitness.
SignatureData() {}
explicit SignatureData(const CScript& script) : scriptSig(script) {}
};
/** Produce a script signature using a generic signature creator. */
bool ProduceSignature(const SigningProvider& provider, const BaseSignatureCreator& creator, const CScript& scriptPubKey, SignatureData& sigdata);
/** Produce a script signature for a transaction. */
bool SignSignature(const SigningProvider &provider, const CScript& fromPubKey, CMutableTransaction& txTo, unsigned int nIn, const CAmount& amount, int nHashType);
bool SignSignature(const SigningProvider &provider, const CTransaction& txFrom, CMutableTransaction& txTo, unsigned int nIn, int nHashType);
/** Combine two script signatures using a generic signature checker, intelligently, possibly with OP_0 placeholders. */
SignatureData CombineSignatures(const CScript& scriptPubKey, const BaseSignatureChecker& checker, const SignatureData& scriptSig1, const SignatureData& scriptSig2);
/** Extract signature data from a transaction input, and insert it. */
SignatureData DataFromTransaction(const CMutableTransaction& tx, unsigned int nIn, const CTxOut& txout);
void UpdateInput(CTxIn& input, const SignatureData& data);
/* Check whether we know how to sign for an output like this, assuming we
* have all private keys. While this function does not need private keys, the passed
* provider is used to look up public keys and redeemscripts by hash.
* Solvability is unrelated to whether we consider this output to be ours. */
bool IsSolvable(const SigningProvider& provider, const CScript& script);
#endif // BITCOIN_SCRIPT_SIGN_H