Differential D8389 Diff 25709 src/script/descriptor.h

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src/script/descriptor.h

// Copyright (c) 2018 The Bitcoin Core developers		// Copyright (c) 2018 The Bitcoin Core developers
// Distributed under the MIT software license, see the accompanying		// Distributed under the MIT software license, see the accompanying
// file COPYING or http://www.opensource.org/licenses/mit-license.php.		// file COPYING or http://www.opensource.org/licenses/mit-license.php.

#ifndef BITCOIN_SCRIPT_DESCRIPTOR_H		#ifndef BITCOIN_SCRIPT_DESCRIPTOR_H
#define BITCOIN_SCRIPT_DESCRIPTOR_H		#define BITCOIN_SCRIPT_DESCRIPTOR_H

#include <script/script.h>		#include <script/script.h>
#include <script/sign.h>		#include <script/sign.h>
#include <script/signingprovider.h>		#include <script/signingprovider.h>

#include <vector>		#include <vector>

// Descriptors are strings that describe a set of scriptPubKeys, together with		/**
// all information necessary to solve them. By combining all information into		* \brief Interface for parsed descriptor objects.
// one, they avoid the need to separately import keys and scripts.		*
//		* Descriptors are strings that describe a set of scriptPubKeys, together with
// Descriptors may be ranged, which occurs when the public keys inside are		* all information necessary to solve them. By combining all information into
// specified in the form of HD chains (xpubs).		* one, they avoid the need to separately import keys and scripts.
//		*
// Descriptors always represent public information - public keys and scripts -		* Descriptors may be ranged, which occurs when the public keys inside are
// but in cases where private keys need to be conveyed along with a descriptor,		* specified in the form of HD chains (xpubs).
// they can be included inside by changing public keys to private keys (WIF		*
// format), and changing xpubs by xprvs.		* Descriptors always represent public information - public keys and scripts -
//		* but in cases where private keys need to be conveyed along with a descriptor,
// Reference documentation about the descriptor language can be found in		* they can be included inside by changing public keys to private keys (WIF
// doc/descriptors.md.		* format), and changing xpubs by xprvs.
		*
/** Interface for parsed descriptor objects. */		* Reference documentation about the descriptor language can be found in
		* doc/descriptors.md.
		*/
struct Descriptor {		struct Descriptor {
virtual ~Descriptor() = default;		virtual ~Descriptor() = default;

/** Whether the expansion of this descriptor depends on the position. */		/** Whether the expansion of this descriptor depends on the position. */
virtual bool IsRange() const = 0;		virtual bool IsRange() const = 0;

/**		/**
* Whether this descriptor has all information about signing ignoring lack		* Whether this descriptor has all information about signing ignoring lack
Show All 10 Lines	struct Descriptor {
* provider does not have the relevant private keys.		* provider does not have the relevant private keys.
*/		*/
virtual bool ToPrivateString(const SigningProvider &provider,		virtual bool ToPrivateString(const SigningProvider &provider,
std::string &out) const = 0;		std::string &out) const = 0;

/**		/**
* Expand a descriptor at a specified position.		* Expand a descriptor at a specified position.
*		*
* pos: the position at which to expand the descriptor. If IsRange() is		* @param[in] pos: The position at which to expand the descriptor. If
* false, this is ignored.		* IsRange() is false, this is ignored.
* provider: the provider to query for private keys in case of hardened		* @param[in] provider: The provider to query for private keys in case of
* derivation.		* hardened derivation.
* output_scripts: the expanded scriptPubKeys will be put here.		* @param[out] output_scripts: The expanded scriptPubKeys.
* out: scripts and public keys necessary for solving the expanded		* @param[out] out: Scripts and public keys necessary for solving the
* scriptPubKeys will be put here (may be equal to provider).		* expanded scriptPubKeys (may be equal to `provider`).
* cache: vector which will be overwritten with cache data necessary to		* @param[out] cache: Cache data necessary to evaluate the descriptor at
* evaluate the descriptor at this point without access to private		* this point without access to private keys.
* keys.
*/		*/
virtual bool Expand(int pos, const SigningProvider &provider,		virtual bool Expand(int pos, const SigningProvider &provider,
std::vector<CScript> &output_scripts,		std::vector<CScript> &output_scripts,
FlatSigningProvider &out,		FlatSigningProvider &out,
std::vector<uint8_t> *cache = nullptr) const = 0;		std::vector<uint8_t> *cache = nullptr) const = 0;

/**		/**
* Expand a descriptor at a specified position using cached expansion data.		* Expand a descriptor at a specified position using cached expansion data.
*		*
* pos: the position at which to expand the descriptor. If IsRange() is		* @param[in] pos: The position at which to expand the descriptor. If
* false, this is ignored.		* IsRange() is false, this is ignored.
* cache: vector from which cached expansion data will be read.		* @param[in] cache: Cached expansion data.
* output_scripts: the expanded scriptPubKeys will be put here.		* @param[out] output_scripts: The expanded scriptPubKeys.
* out: scripts and public keys necessary for solving the expanded		* @param[out] out: Scripts and public keys necessary for solving the
* scriptPubKeys will be put here (may be equal to provider).		* expanded scriptPubKeys (may be equal to `provider`).
*/		*/
virtual bool ExpandFromCache(int pos, const std::vector<uint8_t> &cache,		virtual bool ExpandFromCache(int pos, const std::vector<uint8_t> &cache,
std::vector<CScript> &output_scripts,		std::vector<CScript> &output_scripts,
FlatSigningProvider &out) const = 0;		FlatSigningProvider &out) const = 0;

/**		/**
* Expand the private key for a descriptor at a specified position, if		* Expand the private key for a descriptor at a specified position, if
* possible.		* possible.
*		*
* pos: the position at which to expand the descriptor. If IsRange() is		* @param[in] pos: The position at which to expand the descriptor. If
* false, this is ignored.		* IsRange() is false, this is ignored.
* provider: the provider to query for the private keys.		* @param[in] provider: The provider to query for the private keys.
* out: any private keys available for the specified pos will be placed		* @param[out] out: Any private keys available for the specified `pos`.
* here.
*/		*/
virtual void ExpandPrivate(int pos, const SigningProvider &provider,		virtual void ExpandPrivate(int pos, const SigningProvider &provider,
FlatSigningProvider &out) const = 0;		FlatSigningProvider &out) const = 0;
};		};

/**		/**
* Parse a descriptor string. Included private keys are put in out.		* Parse a `descriptor` string. Included private keys are put in `out`.
*		*
* If the descriptor has a checksum, it must be valid. If require_checksum		* If the descriptor has a checksum, it must be valid. If `require_checksum`
* is set, the checksum is mandatory - otherwise it is optional.		* is set, the checksum is mandatory - otherwise it is optional.
*		*
* If a parse error occurs, or the checksum is missing/invalid, or anything		* If a parse error occurs, or the checksum is missing/invalid, or anything
* else is wrong, nullptr is returned.		* else is wrong, `nullptr` is returned.
*/		*/
std::unique_ptr<Descriptor> Parse(const std::string &descriptor,		std::unique_ptr<Descriptor> Parse(const std::string &descriptor,
FlatSigningProvider &out, std::string &error,		FlatSigningProvider &out, std::string &error,
bool require_checksum = false);		bool require_checksum = false);

/**		/**
* Get the checksum for a descriptor.		* Get the checksum for a `descriptor`.
*		*
* If it already has one, and it is correct, return the checksum in the input.		* - If it already has one, and it is correct, return the checksum in the input.
* If it already has one that is wrong, return "".		* - If it already has one that is wrong, return "".
* If it does not already have one, return the checksum that would need to be		* - If it does not already have one, return the checksum that would need to be
* added.		* added.
*/		*/
std::string GetDescriptorChecksum(const std::string &descriptor);		std::string GetDescriptorChecksum(const std::string &descriptor);

/**		/**
* Find a descriptor for the specified script, using information from provider		* Find a descriptor for the specified `script`, using information from
* where possible.		* `provider` where possible.
*		*
* A non-ranged descriptor which only generates the specified script will be		* A non-ranged descriptor which only generates the specified script will be
* returned in all circumstances.		* returned in all circumstances.
*		*
* For public keys with key origin information, this information will be		* For public keys with key origin information, this information will be
* preserved in the returned descriptor.		* preserved in the returned descriptor.
*		*
* - If all information for solving `script` is present in `provider`, a		* - If all information for solving `script` is present in `provider`, a
* descriptor will be returned which is `IsSolvable()` and encapsulates said		* descriptor will be returned which is IsSolvable() and encapsulates said
* information.		* information.
* - Failing that, if `script` corresponds to a known address type, an "addr()"		* - Failing that, if `script` corresponds to a known address type, an "addr()"
* descriptor will be returned (which is not `IsSolvable()`).		* descriptor will be returned (which is not IsSolvable()).
* - Failing that, a "raw()" descriptor is returned.		* - Failing that, a "raw()" descriptor is returned.
*/		*/
std::unique_ptr<Descriptor> InferDescriptor(const CScript &script,		std::unique_ptr<Descriptor> InferDescriptor(const CScript &script,
const SigningProvider &provider);		const SigningProvider &provider);

#endif // BITCOIN_SCRIPT_DESCRIPTOR_H		#endif // BITCOIN_SCRIPT_DESCRIPTOR_H