diff options
author | MeshCollider <dobsonsa68@gmail.com> | 2018-12-12 16:31:52 +1300 |
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committer | MeshCollider <dobsonsa68@gmail.com> | 2018-12-12 17:24:26 +1300 |
commit | 3fff1ab817e7995720c3aa0374807ed70d1a4d24 (patch) | |
tree | 74d615745c2e2356eff2178f93d646c316d789b7 /src | |
parent | f65bce858f266b352c9ddd1f5480431dca56fcae (diff) | |
parent | 26879509f1a3b9fc0fa616164e5a88fdb344ac4d (diff) | |
download | bitcoin-3fff1ab817e7995720c3aa0374807ed70d1a4d24.tar.xz |
Merge #14646: Add expansion cache functions to descriptors (unused for now)
26879509f Add comments to descriptor tests (Pieter Wuille)
82df4c64f Add descriptor expansion cache (Pieter Wuille)
1eda33aab [refactor] Combine the ToString and ToPrivateString implementations (Pieter Wuille)
24d3a7b3a [refactor] Use DescriptorImpl internally, permitting access to new methods (Pieter Wuille)
6be0fb4b3 [refactor] Add a base DescriptorImpl with most common logic (Pieter Wuille)
Pull request description:
This patch modifies the internal `Descriptor` class to optionally construct and use an "expansion cache". Such a cache is a byte array that encodes all information necessary to expand a `Descriptor` a second time without access to private keys, and without the need to perform expensive BIP32 derivations. For all currently defined descriptors, the cache simply contains a concatenation of all public keys used.
This is motivated by the goal of importing a descriptor into the wallet and using it as a replacement for the keypool, where it would be impossible to expand descriptors if they use hardened derivation.
Tree-SHA512: f531a0a82ec1eecc30b78ba8a31724d1249826b028cc3543ad32372e1aedd537f137ab03dbffc222c5df444d5865ecd5cec754c1ae1d4989b6e9baeaffade32a
Diffstat (limited to 'src')
-rw-r--r-- | src/script/descriptor.cpp | 444 | ||||
-rw-r--r-- | src/script/descriptor.h | 12 | ||||
-rw-r--r-- | src/script/sign.cpp | 2 | ||||
-rw-r--r-- | src/test/descriptor_tests.cpp | 36 |
4 files changed, 287 insertions, 207 deletions
diff --git a/src/script/descriptor.cpp b/src/script/descriptor.cpp index ca80d3451f..a702be5b78 100644 --- a/src/script/descriptor.cpp +++ b/src/script/descriptor.cpp @@ -40,8 +40,8 @@ struct PubkeyProvider { virtual ~PubkeyProvider() = default; - /** Derive a public key. */ - virtual bool GetPubKey(int pos, const SigningProvider& arg, CPubKey& key, KeyOriginInfo& info) const = 0; + /** Derive a public key. If key==nullptr, only info is desired. */ + virtual bool GetPubKey(int pos, const SigningProvider& arg, CPubKey* key, KeyOriginInfo& info) const = 0; /** Whether this represent multiple public keys at different positions. */ virtual bool IsRange() const = 0; @@ -68,7 +68,7 @@ class OriginPubkeyProvider final : public PubkeyProvider public: OriginPubkeyProvider(KeyOriginInfo info, std::unique_ptr<PubkeyProvider> provider) : m_origin(std::move(info)), m_provider(std::move(provider)) {} - bool GetPubKey(int pos, const SigningProvider& arg, CPubKey& key, KeyOriginInfo& info) const override + bool GetPubKey(int pos, const SigningProvider& arg, CPubKey* key, KeyOriginInfo& info) const override { if (!m_provider->GetPubKey(pos, arg, key, info)) return false; std::copy(std::begin(m_origin.fingerprint), std::end(m_origin.fingerprint), info.fingerprint); @@ -94,9 +94,9 @@ class ConstPubkeyProvider final : public PubkeyProvider public: ConstPubkeyProvider(const CPubKey& pubkey) : m_pubkey(pubkey) {} - bool GetPubKey(int pos, const SigningProvider& arg, CPubKey& key, KeyOriginInfo& info) const override + bool GetPubKey(int pos, const SigningProvider& arg, CPubKey* key, KeyOriginInfo& info) const override { - key = m_pubkey; + if (key) *key = m_pubkey; info.path.clear(); CKeyID keyid = m_pubkey.GetID(); std::copy(keyid.begin(), keyid.begin() + sizeof(info.fingerprint), info.fingerprint); @@ -152,26 +152,28 @@ public: BIP32PubkeyProvider(const CExtPubKey& extkey, KeyPath path, DeriveType derive) : m_extkey(extkey), m_path(std::move(path)), m_derive(derive) {} bool IsRange() const override { return m_derive != DeriveType::NO; } size_t GetSize() const override { return 33; } - bool GetPubKey(int pos, const SigningProvider& arg, CPubKey& key, KeyOriginInfo& info) const override + bool GetPubKey(int pos, const SigningProvider& arg, CPubKey* key, KeyOriginInfo& info) const override { - if (IsHardened()) { - CExtKey extkey; - if (!GetExtKey(arg, extkey)) return false; - for (auto entry : m_path) { - extkey.Derive(extkey, entry); + if (key) { + if (IsHardened()) { + CExtKey extkey; + if (!GetExtKey(arg, extkey)) return false; + for (auto entry : m_path) { + extkey.Derive(extkey, entry); + } + if (m_derive == DeriveType::UNHARDENED) extkey.Derive(extkey, pos); + if (m_derive == DeriveType::HARDENED) extkey.Derive(extkey, pos | 0x80000000UL); + *key = extkey.Neuter().pubkey; + } else { + // TODO: optimize by caching + CExtPubKey extkey = m_extkey; + for (auto entry : m_path) { + extkey.Derive(extkey, entry); + } + if (m_derive == DeriveType::UNHARDENED) extkey.Derive(extkey, pos); + assert(m_derive != DeriveType::HARDENED); + *key = extkey.pubkey; } - if (m_derive == DeriveType::UNHARDENED) extkey.Derive(extkey, pos); - if (m_derive == DeriveType::HARDENED) extkey.Derive(extkey, pos | 0x80000000UL); - key = extkey.Neuter().pubkey; - } else { - // TODO: optimize by caching - CExtPubKey extkey = m_extkey; - for (auto entry : m_path) { - extkey.Derive(extkey, entry); - } - if (m_derive == DeriveType::UNHARDENED) extkey.Derive(extkey, pos); - assert(m_derive != DeriveType::HARDENED); - key = extkey.pubkey; } CKeyID keyid = m_extkey.pubkey.GetID(); std::copy(keyid.begin(), keyid.begin() + sizeof(info.fingerprint), info.fingerprint); @@ -202,129 +204,119 @@ public: } }; -/** A parsed addr(A) descriptor. */ -class AddressDescriptor final : public Descriptor -{ - CTxDestination m_destination; - -public: - AddressDescriptor(CTxDestination destination) : m_destination(std::move(destination)) {} - - bool IsRange() const override { return false; } - bool IsSolvable() const override { return false; } - std::string ToString() const override { return "addr(" + EncodeDestination(m_destination) + ")"; } - bool ToPrivateString(const SigningProvider& arg, std::string& out) const override { out = ToString(); return true; } - bool Expand(int pos, const SigningProvider& arg, std::vector<CScript>& output_scripts, FlatSigningProvider& out) const override - { - output_scripts = std::vector<CScript>{GetScriptForDestination(m_destination)}; - return true; - } -}; - -/** A parsed raw(H) descriptor. */ -class RawDescriptor final : public Descriptor -{ - CScript m_script; - -public: - RawDescriptor(CScript script) : m_script(std::move(script)) {} - - bool IsRange() const override { return false; } - bool IsSolvable() const override { return false; } - std::string ToString() const override { return "raw(" + HexStr(m_script.begin(), m_script.end()) + ")"; } - bool ToPrivateString(const SigningProvider& arg, std::string& out) const override { out = ToString(); return true; } - bool Expand(int pos, const SigningProvider& arg, std::vector<CScript>& output_scripts, FlatSigningProvider& out) const override - { - output_scripts = std::vector<CScript>{m_script}; - return true; - } -}; - -/** A parsed pk(P), pkh(P), or wpkh(P) descriptor. */ -class SingleKeyDescriptor final : public Descriptor +/** Base class for all Descriptor implementations. */ +class DescriptorImpl : public Descriptor { - const std::function<CScript(const CPubKey&)> m_script_fn; - const std::string m_fn_name; - std::unique_ptr<PubkeyProvider> m_provider; + //! Public key arguments for this descriptor (size 1 for PK, PKH, WPKH; any size of Multisig). + const std::vector<std::unique_ptr<PubkeyProvider>> m_pubkey_args; + //! The sub-descriptor argument (nullptr for everything but SH and WSH). + const std::unique_ptr<DescriptorImpl> m_script_arg; + //! The string name of the descriptor function. + const std::string m_name; + +protected: + //! Return a serialization of anything except pubkey and script arguments, to be prepended to those. + virtual std::string ToStringExtra() const { return ""; } + + /** A helper function to construct the scripts for this descriptor. + * + * This function is invoked once for every CScript produced by evaluating + * m_script_arg, or just once in case m_script_arg is nullptr. + + * @param pubkeys The evaluations of the m_pubkey_args field. + * @param script The evaluation of m_script_arg (or nullptr when m_script_arg is nullptr). + * @param out A FlatSigningProvider to put scripts or public keys in that are necessary to the solver. + * The script and pubkeys argument to this function are automatically added. + * @return A vector with scriptPubKeys for this descriptor. + */ + virtual std::vector<CScript> MakeScripts(const std::vector<CPubKey>& pubkeys, const CScript* script, FlatSigningProvider& out) const = 0; public: - SingleKeyDescriptor(std::unique_ptr<PubkeyProvider> prov, const std::function<CScript(const CPubKey&)>& fn, const std::string& name) : m_script_fn(fn), m_fn_name(name), m_provider(std::move(prov)) {} + DescriptorImpl(std::vector<std::unique_ptr<PubkeyProvider>> pubkeys, std::unique_ptr<DescriptorImpl> script, const std::string& name) : m_pubkey_args(std::move(pubkeys)), m_script_arg(std::move(script)), m_name(name) {} - bool IsRange() const override { return m_provider->IsRange(); } - bool IsSolvable() const override { return true; } - std::string ToString() const override { return m_fn_name + "(" + m_provider->ToString() + ")"; } - bool ToPrivateString(const SigningProvider& arg, std::string& out) const override - { - std::string ret; - if (!m_provider->ToPrivateString(arg, ret)) return false; - out = m_fn_name + "(" + std::move(ret) + ")"; - return true; - } - bool Expand(int pos, const SigningProvider& arg, std::vector<CScript>& output_scripts, FlatSigningProvider& out) const override + bool IsSolvable() const override { - CPubKey key; - KeyOriginInfo info; - if (!m_provider->GetPubKey(pos, arg, key, info)) return false; - output_scripts = std::vector<CScript>{m_script_fn(key)}; - out.origins.emplace(key.GetID(), std::move(info)); - out.pubkeys.emplace(key.GetID(), key); + if (m_script_arg) { + if (!m_script_arg->IsSolvable()) return false; + } return true; } -}; - -CScript P2PKHGetScript(const CPubKey& pubkey) { return GetScriptForDestination(pubkey.GetID()); } -CScript P2PKGetScript(const CPubKey& pubkey) { return GetScriptForRawPubKey(pubkey); } -CScript P2WPKHGetScript(const CPubKey& pubkey) { return GetScriptForDestination(WitnessV0KeyHash(pubkey.GetID())); } - -/** A parsed multi(...) descriptor. */ -class MultisigDescriptor : public Descriptor -{ - int m_threshold; - std::vector<std::unique_ptr<PubkeyProvider>> m_providers; -public: - MultisigDescriptor(int threshold, std::vector<std::unique_ptr<PubkeyProvider>> providers) : m_threshold(threshold), m_providers(std::move(providers)) {} - - bool IsRange() const override + bool IsRange() const final { - for (const auto& p : m_providers) { - if (p->IsRange()) return true; + for (const auto& pubkey : m_pubkey_args) { + if (pubkey->IsRange()) return true; + } + if (m_script_arg) { + if (m_script_arg->IsRange()) return true; } return false; } - bool IsSolvable() const override { return true; } - - std::string ToString() const override + bool ToStringHelper(const SigningProvider* arg, std::string& out, bool priv) const { - std::string ret = strprintf("multi(%i", m_threshold); - for (const auto& p : m_providers) { - ret += "," + p->ToString(); + std::string extra = ToStringExtra(); + size_t pos = extra.size() > 0 ? 1 : 0; + std::string ret = m_name + "(" + extra; + for (const auto& pubkey : m_pubkey_args) { + if (pos++) ret += ","; + std::string tmp; + if (priv) { + if (!pubkey->ToPrivateString(*arg, tmp)) return false; + } else { + tmp = pubkey->ToString(); + } + ret += std::move(tmp); } - return std::move(ret) + ")"; - } - - bool ToPrivateString(const SigningProvider& arg, std::string& out) const override - { - std::string ret = strprintf("multi(%i", m_threshold); - for (const auto& p : m_providers) { - std::string sub; - if (!p->ToPrivateString(arg, sub)) return false; - ret += "," + std::move(sub); + if (m_script_arg) { + if (pos++) ret += ","; + std::string tmp; + if (!m_script_arg->ToStringHelper(arg, tmp, priv)) return false; + ret += std::move(tmp); } out = std::move(ret) + ")"; return true; } - bool Expand(int pos, const SigningProvider& arg, std::vector<CScript>& output_scripts, FlatSigningProvider& out) const override + std::string ToString() const final + { + std::string ret; + ToStringHelper(nullptr, ret, false); + return ret; + } + + bool ToPrivateString(const SigningProvider& arg, std::string& out) const override final { return ToStringHelper(&arg, out, true); } + + bool ExpandHelper(int pos, const SigningProvider& arg, Span<const unsigned char>* cache_read, std::vector<CScript>& output_scripts, FlatSigningProvider& out, std::vector<unsigned char>* cache_write) const { std::vector<std::pair<CPubKey, KeyOriginInfo>> entries; - entries.reserve(m_providers.size()); - // Construct temporary data in `entries`, to avoid producing output in case of failure. - for (const auto& p : m_providers) { + entries.reserve(m_pubkey_args.size()); + + // Construct temporary data in `entries` and `subscripts`, to avoid producing output in case of failure. + for (const auto& p : m_pubkey_args) { entries.emplace_back(); - if (!p->GetPubKey(pos, arg, entries.back().first, entries.back().second)) return false; + if (!p->GetPubKey(pos, arg, cache_read ? nullptr : &entries.back().first, entries.back().second)) return false; + if (cache_read) { + // Cached expanded public key exists, use it. + if (cache_read->size() == 0) return false; + bool compressed = ((*cache_read)[0] == 0x02 || (*cache_read)[0] == 0x03) && cache_read->size() >= 33; + bool uncompressed = ((*cache_read)[0] == 0x04) && cache_read->size() >= 65; + if (!(compressed || uncompressed)) return false; + CPubKey pubkey(cache_read->begin(), cache_read->begin() + (compressed ? 33 : 65)); + entries.back().first = pubkey; + *cache_read = cache_read->subspan(compressed ? 33 : 65); + } + if (cache_write) { + cache_write->insert(cache_write->end(), entries.back().first.begin(), entries.back().first.end()); + } } + std::vector<CScript> subscripts; + if (m_script_arg) { + FlatSigningProvider subprovider; + if (!m_script_arg->ExpandHelper(pos, arg, cache_read, subscripts, subprovider, cache_write)) return false; + out = Merge(out, subprovider); + } + std::vector<CPubKey> pubkeys; pubkeys.reserve(entries.size()); for (auto& entry : entries) { @@ -332,89 +324,141 @@ public: out.origins.emplace(entry.first.GetID(), std::move(entry.second)); out.pubkeys.emplace(entry.first.GetID(), entry.first); } - output_scripts = std::vector<CScript>{GetScriptForMultisig(m_threshold, pubkeys)}; + if (m_script_arg) { + for (const auto& subscript : subscripts) { + out.scripts.emplace(CScriptID(subscript), subscript); + std::vector<CScript> addscripts = MakeScripts(pubkeys, &subscript, out); + for (auto& addscript : addscripts) { + output_scripts.push_back(std::move(addscript)); + } + } + } else { + output_scripts = MakeScripts(pubkeys, nullptr, out); + } return true; } + + bool Expand(int pos, const SigningProvider& provider, std::vector<CScript>& output_scripts, FlatSigningProvider& out, std::vector<unsigned char>* cache = nullptr) const final + { + return ExpandHelper(pos, provider, nullptr, output_scripts, out, cache); + } + + bool ExpandFromCache(int pos, const std::vector<unsigned char>& cache, std::vector<CScript>& output_scripts, FlatSigningProvider& out) const final + { + Span<const unsigned char> span = MakeSpan(cache); + return ExpandHelper(pos, DUMMY_SIGNING_PROVIDER, &span, output_scripts, out, nullptr) && span.size() == 0; + } }; -/** A parsed sh(S) or wsh(S) descriptor. */ -class ConvertorDescriptor : public Descriptor +/** Construct a vector with one element, which is moved into it. */ +template<typename T> +std::vector<T> Singleton(T elem) { - const std::function<CScript(const CScript&)> m_convert_fn; - const std::string m_fn_name; - std::unique_ptr<Descriptor> m_descriptor; + std::vector<T> ret; + ret.emplace_back(std::move(elem)); + return ret; +} +/** A parsed addr(A) descriptor. */ +class AddressDescriptor final : public DescriptorImpl +{ + const CTxDestination m_destination; +protected: + std::string ToStringExtra() const override { return EncodeDestination(m_destination); } + std::vector<CScript> MakeScripts(const std::vector<CPubKey>&, const CScript*, FlatSigningProvider&) const override { return Singleton(GetScriptForDestination(m_destination)); } public: - ConvertorDescriptor(std::unique_ptr<Descriptor> descriptor, const std::function<CScript(const CScript&)>& fn, const std::string& name) : m_convert_fn(fn), m_fn_name(name), m_descriptor(std::move(descriptor)) {} + AddressDescriptor(CTxDestination destination) : DescriptorImpl({}, {}, "addr"), m_destination(std::move(destination)) {} + bool IsSolvable() const final { return false; } +}; - bool IsRange() const override { return m_descriptor->IsRange(); } - bool IsSolvable() const override { return m_descriptor->IsSolvable(); } - std::string ToString() const override { return m_fn_name + "(" + m_descriptor->ToString() + ")"; } - bool ToPrivateString(const SigningProvider& arg, std::string& out) const override - { - std::string ret; - if (!m_descriptor->ToPrivateString(arg, ret)) return false; - out = m_fn_name + "(" + std::move(ret) + ")"; - return true; - } - bool Expand(int pos, const SigningProvider& arg, std::vector<CScript>& output_scripts, FlatSigningProvider& out) const override - { - std::vector<CScript> sub; - if (!m_descriptor->Expand(pos, arg, sub, out)) return false; - output_scripts.clear(); - for (const auto& script : sub) { - CScriptID id(script); - out.scripts.emplace(CScriptID(script), script); - output_scripts.push_back(m_convert_fn(script)); - } - return true; - } +/** A parsed raw(H) descriptor. */ +class RawDescriptor final : public DescriptorImpl +{ + const CScript m_script; +protected: + std::string ToStringExtra() const override { return HexStr(m_script.begin(), m_script.end()); } + std::vector<CScript> MakeScripts(const std::vector<CPubKey>&, const CScript*, FlatSigningProvider&) const override { return Singleton(m_script); } +public: + RawDescriptor(CScript script) : DescriptorImpl({}, {}, "raw"), m_script(std::move(script)) {} + bool IsSolvable() const final { return false; } }; -CScript ConvertP2SH(const CScript& script) { return GetScriptForDestination(CScriptID(script)); } -CScript ConvertP2WSH(const CScript& script) { return GetScriptForDestination(WitnessV0ScriptHash(script)); } +/** A parsed pk(P) descriptor. */ +class PKDescriptor final : public DescriptorImpl +{ +protected: + std::vector<CScript> MakeScripts(const std::vector<CPubKey>& keys, const CScript*, FlatSigningProvider&) const override { return Singleton(GetScriptForRawPubKey(keys[0])); } +public: + PKDescriptor(std::unique_ptr<PubkeyProvider> prov) : DescriptorImpl(Singleton(std::move(prov)), {}, "pk") {} +}; -/** A parsed combo(P) descriptor. */ -class ComboDescriptor final : public Descriptor +/** A parsed pkh(P) descriptor. */ +class PKHDescriptor final : public DescriptorImpl { - std::unique_ptr<PubkeyProvider> m_provider; +protected: + std::vector<CScript> MakeScripts(const std::vector<CPubKey>& keys, const CScript*, FlatSigningProvider&) const override { return Singleton(GetScriptForDestination(keys[0].GetID())); } +public: + PKHDescriptor(std::unique_ptr<PubkeyProvider> prov) : DescriptorImpl(Singleton(std::move(prov)), {}, "pkh") {} +}; +/** A parsed wpkh(P) descriptor. */ +class WPKHDescriptor final : public DescriptorImpl +{ +protected: + std::vector<CScript> MakeScripts(const std::vector<CPubKey>& keys, const CScript*, FlatSigningProvider&) const override { return Singleton(GetScriptForDestination(WitnessV0KeyHash(keys[0].GetID()))); } public: - ComboDescriptor(std::unique_ptr<PubkeyProvider> provider) : m_provider(std::move(provider)) {} + WPKHDescriptor(std::unique_ptr<PubkeyProvider> prov) : DescriptorImpl(Singleton(std::move(prov)), {}, "wpkh") {} +}; - bool IsRange() const override { return m_provider->IsRange(); } - bool IsSolvable() const override { return true; } - std::string ToString() const override { return "combo(" + m_provider->ToString() + ")"; } - bool ToPrivateString(const SigningProvider& arg, std::string& out) const override - { - std::string ret; - if (!m_provider->ToPrivateString(arg, ret)) return false; - out = "combo(" + std::move(ret) + ")"; - return true; - } - bool Expand(int pos, const SigningProvider& arg, std::vector<CScript>& output_scripts, FlatSigningProvider& out) const override +/** A parsed combo(P) descriptor. */ +class ComboDescriptor final : public DescriptorImpl +{ +protected: + std::vector<CScript> MakeScripts(const std::vector<CPubKey>& keys, const CScript*, FlatSigningProvider& out) const override { - CPubKey key; - KeyOriginInfo info; - if (!m_provider->GetPubKey(pos, arg, key, info)) return false; - CKeyID keyid = key.GetID(); - { - CScript p2pk = GetScriptForRawPubKey(key); - CScript p2pkh = GetScriptForDestination(keyid); - output_scripts = std::vector<CScript>{std::move(p2pk), std::move(p2pkh)}; - out.pubkeys.emplace(keyid, key); - out.origins.emplace(keyid, std::move(info)); - } - if (key.IsCompressed()) { - CScript p2wpkh = GetScriptForDestination(WitnessV0KeyHash(keyid)); - CScriptID p2wpkh_id(p2wpkh); - CScript p2sh_p2wpkh = GetScriptForDestination(p2wpkh_id); - out.scripts.emplace(p2wpkh_id, p2wpkh); - output_scripts.push_back(std::move(p2wpkh)); - output_scripts.push_back(std::move(p2sh_p2wpkh)); + std::vector<CScript> ret; + CKeyID id = keys[0].GetID(); + ret.emplace_back(GetScriptForRawPubKey(keys[0])); // P2PK + ret.emplace_back(GetScriptForDestination(id)); // P2PKH + if (keys[0].IsCompressed()) { + CScript p2wpkh = GetScriptForDestination(WitnessV0KeyHash(id)); + out.scripts.emplace(CScriptID(p2wpkh), p2wpkh); + ret.emplace_back(p2wpkh); + ret.emplace_back(GetScriptForDestination(CScriptID(p2wpkh))); // P2SH-P2WPKH } - return true; + return ret; } +public: + ComboDescriptor(std::unique_ptr<PubkeyProvider> prov) : DescriptorImpl(Singleton(std::move(prov)), {}, "combo") {} +}; + +/** A parsed multi(...) descriptor. */ +class MultisigDescriptor final : public DescriptorImpl +{ + const int m_threshold; +protected: + std::string ToStringExtra() const override { return strprintf("%i", m_threshold); } + std::vector<CScript> MakeScripts(const std::vector<CPubKey>& keys, const CScript*, FlatSigningProvider&) const override { return Singleton(GetScriptForMultisig(m_threshold, keys)); } +public: + MultisigDescriptor(int threshold, std::vector<std::unique_ptr<PubkeyProvider>> providers) : DescriptorImpl(std::move(providers), {}, "multi"), m_threshold(threshold) {} +}; + +/** A parsed sh(...) descriptor. */ +class SHDescriptor final : public DescriptorImpl +{ +protected: + std::vector<CScript> MakeScripts(const std::vector<CPubKey>&, const CScript* script, FlatSigningProvider&) const override { return Singleton(GetScriptForDestination(CScriptID(*script))); } +public: + SHDescriptor(std::unique_ptr<DescriptorImpl> desc) : DescriptorImpl({}, std::move(desc), "sh") {} +}; + +/** A parsed wsh(...) descriptor. */ +class WSHDescriptor final : public DescriptorImpl +{ +protected: + std::vector<CScript> MakeScripts(const std::vector<CPubKey>&, const CScript* script, FlatSigningProvider&) const override { return Singleton(GetScriptForDestination(WitnessV0ScriptHash(*script))); } +public: + WSHDescriptor(std::unique_ptr<DescriptorImpl> desc) : DescriptorImpl({}, std::move(desc), "wsh") {} }; //////////////////////////////////////////////////////////////////////////// @@ -562,18 +606,18 @@ std::unique_ptr<PubkeyProvider> ParsePubkey(const Span<const char>& sp, bool per } /** Parse a script in a particular context. */ -std::unique_ptr<Descriptor> ParseScript(Span<const char>& sp, ParseScriptContext ctx, FlatSigningProvider& out) +std::unique_ptr<DescriptorImpl> ParseScript(Span<const char>& sp, ParseScriptContext ctx, FlatSigningProvider& out) { auto expr = Expr(sp); if (Func("pk", expr)) { auto pubkey = ParsePubkey(expr, ctx != ParseScriptContext::P2WSH, out); if (!pubkey) return nullptr; - return MakeUnique<SingleKeyDescriptor>(std::move(pubkey), P2PKGetScript, "pk"); + return MakeUnique<PKDescriptor>(std::move(pubkey)); } if (Func("pkh", expr)) { auto pubkey = ParsePubkey(expr, ctx != ParseScriptContext::P2WSH, out); if (!pubkey) return nullptr; - return MakeUnique<SingleKeyDescriptor>(std::move(pubkey), P2PKHGetScript, "pkh"); + return MakeUnique<PKHDescriptor>(std::move(pubkey)); } if (ctx == ParseScriptContext::TOP && Func("combo", expr)) { auto pubkey = ParsePubkey(expr, true, out); @@ -606,17 +650,17 @@ std::unique_ptr<Descriptor> ParseScript(Span<const char>& sp, ParseScriptContext if (ctx != ParseScriptContext::P2WSH && Func("wpkh", expr)) { auto pubkey = ParsePubkey(expr, false, out); if (!pubkey) return nullptr; - return MakeUnique<SingleKeyDescriptor>(std::move(pubkey), P2WPKHGetScript, "wpkh"); + return MakeUnique<WPKHDescriptor>(std::move(pubkey)); } if (ctx == ParseScriptContext::TOP && Func("sh", expr)) { auto desc = ParseScript(expr, ParseScriptContext::P2SH, out); if (!desc || expr.size()) return nullptr; - return MakeUnique<ConvertorDescriptor>(std::move(desc), ConvertP2SH, "sh"); + return MakeUnique<SHDescriptor>(std::move(desc)); } if (ctx != ParseScriptContext::P2WSH && Func("wsh", expr)) { auto desc = ParseScript(expr, ParseScriptContext::P2WSH, out); if (!desc || expr.size()) return nullptr; - return MakeUnique<ConvertorDescriptor>(std::move(desc), ConvertP2WSH, "wsh"); + return MakeUnique<WSHDescriptor>(std::move(desc)); } if (ctx == ParseScriptContext::TOP && Func("addr", expr)) { CTxDestination dest = DecodeDestination(std::string(expr.begin(), expr.end())); @@ -642,7 +686,7 @@ std::unique_ptr<PubkeyProvider> InferPubkey(const CPubKey& pubkey, ParseScriptCo return key_provider; } -std::unique_ptr<Descriptor> InferScript(const CScript& script, ParseScriptContext ctx, const SigningProvider& provider) +std::unique_ptr<DescriptorImpl> InferScript(const CScript& script, ParseScriptContext ctx, const SigningProvider& provider) { std::vector<std::vector<unsigned char>> data; txnouttype txntype = Solver(script, data); @@ -650,7 +694,7 @@ std::unique_ptr<Descriptor> InferScript(const CScript& script, ParseScriptContex if (txntype == TX_PUBKEY) { CPubKey pubkey(data[0].begin(), data[0].end()); if (pubkey.IsValid()) { - return MakeUnique<SingleKeyDescriptor>(InferPubkey(pubkey, ctx, provider), P2PKGetScript, "pk"); + return MakeUnique<PKDescriptor>(InferPubkey(pubkey, ctx, provider)); } } if (txntype == TX_PUBKEYHASH) { @@ -658,7 +702,7 @@ std::unique_ptr<Descriptor> InferScript(const CScript& script, ParseScriptContex CKeyID keyid(hash); CPubKey pubkey; if (provider.GetPubKey(keyid, pubkey)) { - return MakeUnique<SingleKeyDescriptor>(InferPubkey(pubkey, ctx, provider), P2PKHGetScript, "pkh"); + return MakeUnique<PKHDescriptor>(InferPubkey(pubkey, ctx, provider)); } } if (txntype == TX_WITNESS_V0_KEYHASH && ctx != ParseScriptContext::P2WSH) { @@ -666,7 +710,7 @@ std::unique_ptr<Descriptor> InferScript(const CScript& script, ParseScriptContex CKeyID keyid(hash); CPubKey pubkey; if (provider.GetPubKey(keyid, pubkey)) { - return MakeUnique<SingleKeyDescriptor>(InferPubkey(pubkey, ctx, provider), P2WPKHGetScript, "wpkh"); + return MakeUnique<WPKHDescriptor>(InferPubkey(pubkey, ctx, provider)); } } if (txntype == TX_MULTISIG) { @@ -683,7 +727,7 @@ std::unique_ptr<Descriptor> InferScript(const CScript& script, ParseScriptContex CScript subscript; if (provider.GetCScript(scriptid, subscript)) { auto sub = InferScript(subscript, ParseScriptContext::P2SH, provider); - if (sub) return MakeUnique<ConvertorDescriptor>(std::move(sub), ConvertP2SH, "sh"); + if (sub) return MakeUnique<SHDescriptor>(std::move(sub)); } } if (txntype == TX_WITNESS_V0_SCRIPTHASH && ctx != ParseScriptContext::P2WSH) { @@ -692,7 +736,7 @@ std::unique_ptr<Descriptor> InferScript(const CScript& script, ParseScriptContex CScript subscript; if (provider.GetCScript(scriptid, subscript)) { auto sub = InferScript(subscript, ParseScriptContext::P2WSH, provider); - if (sub) return MakeUnique<ConvertorDescriptor>(std::move(sub), ConvertP2WSH, "wsh"); + if (sub) return MakeUnique<WSHDescriptor>(std::move(sub)); } } @@ -712,7 +756,7 @@ std::unique_ptr<Descriptor> Parse(const std::string& descriptor, FlatSigningProv { Span<const char> sp(descriptor.data(), descriptor.size()); auto ret = ParseScript(sp, ParseScriptContext::TOP, out); - if (sp.size() == 0 && ret) return ret; + if (sp.size() == 0 && ret) return std::unique_ptr<Descriptor>(std::move(ret)); return nullptr; } diff --git a/src/script/descriptor.h b/src/script/descriptor.h index 0111972f85..44f0efca03 100644 --- a/src/script/descriptor.h +++ b/src/script/descriptor.h @@ -48,8 +48,18 @@ struct Descriptor { * provider: the provider to query for private keys in case of hardened derivation. * output_script: the expanded scriptPubKeys will be put here. * out: scripts and public keys necessary for solving the expanded scriptPubKeys will be put here (may be equal to provider). + * cache: vector which will be overwritten with cache data necessary to-evaluate the descriptor at this point without access to private keys. */ - virtual bool Expand(int pos, const SigningProvider& provider, std::vector<CScript>& output_scripts, FlatSigningProvider& out) const = 0; + virtual bool Expand(int pos, const SigningProvider& provider, std::vector<CScript>& output_scripts, FlatSigningProvider& out, std::vector<unsigned char>* cache = nullptr) const = 0; + + /** Expand a descriptor at a specified position using cached expansion data. + * + * pos: the position at which to expand the descriptor. If IsRange() is false, this is ignored. + * cache: vector from which cached expansion data will be read. + * output_script: the expanded scriptPubKeys will be put here. + * out: scripts and public keys necessary for solving the expanded scriptPubKeys will be put here (may be equal to provider). + */ + virtual bool ExpandFromCache(int pos, const std::vector<unsigned char>& cache, std::vector<CScript>& output_scripts, FlatSigningProvider& out) const = 0; }; /** Parse a descriptor string. Included private keys are put in out. Returns nullptr if parsing fails. */ diff --git a/src/script/sign.cpp b/src/script/sign.cpp index e5651710f1..635e4fa3d2 100644 --- a/src/script/sign.cpp +++ b/src/script/sign.cpp @@ -705,5 +705,7 @@ FlatSigningProvider Merge(const FlatSigningProvider& a, const FlatSigningProvide ret.pubkeys.insert(b.pubkeys.begin(), b.pubkeys.end()); ret.keys = a.keys; ret.keys.insert(b.keys.begin(), b.keys.end()); + ret.origins = a.origins; + ret.origins.insert(b.origins.begin(), b.origins.end()); return ret; } diff --git a/src/test/descriptor_tests.cpp b/src/test/descriptor_tests.cpp index 0e98f5a826..8da8cfc00c 100644 --- a/src/test/descriptor_tests.cpp +++ b/src/test/descriptor_tests.cpp @@ -79,19 +79,42 @@ void Check(const std::string& prv, const std::string& pub, int flags, const std: BOOST_CHECK_EQUAL(parse_pub->IsRange(), (flags & RANGE) != 0); BOOST_CHECK_EQUAL(parse_priv->IsRange(), (flags & RANGE) != 0); - - // Is not ranged descriptor, only a single result is expected. + // * For ranged descriptors, the `scripts` parameter is a list of expected result outputs, for subsequent + // positions to evaluate the descriptors on (so the first element of `scripts` is for evaluating the + // descriptor at 0; the second at 1; and so on). To verify this, we evaluate the descriptors once for + // each element in `scripts`. + // * For non-ranged descriptors, we evaluate the descriptors at positions 0, 1, and 2, but expect the + // same result in each case, namely the first element of `scripts`. Because of that, the size of + // `scripts` must be one in that case. if (!(flags & RANGE)) assert(scripts.size() == 1); - size_t max = (flags & RANGE) ? scripts.size() : 3; + + // Iterate over the position we'll evaluate the descriptors in. for (size_t i = 0; i < max; ++i) { + // Call the expected result scripts `ref`. const auto& ref = scripts[(flags & RANGE) ? i : 0]; + // When t=0, evaluate the `prv` descriptor; when t=1, evaluate the `pub` descriptor. for (int t = 0; t < 2; ++t) { + // When the descriptor is hardened, evaluate with access to the private keys inside. const FlatSigningProvider& key_provider = (flags & HARDENED) ? keys_priv : keys_pub; - FlatSigningProvider script_provider; - std::vector<CScript> spks; - BOOST_CHECK((t ? parse_priv : parse_pub)->Expand(i, key_provider, spks, script_provider)); + + // Evaluate the descriptor selected by `t` in poisition `i`. + FlatSigningProvider script_provider, script_provider_cached; + std::vector<CScript> spks, spks_cached; + std::vector<unsigned char> cache; + BOOST_CHECK((t ? parse_priv : parse_pub)->Expand(i, key_provider, spks, script_provider, &cache)); + + // Compare the output with the expected result. BOOST_CHECK_EQUAL(spks.size(), ref.size()); + + // Try to expand again using cached data, and compare. + BOOST_CHECK(parse_pub->ExpandFromCache(i, cache, spks_cached, script_provider_cached)); + BOOST_CHECK(spks == spks_cached); + BOOST_CHECK(script_provider.pubkeys == script_provider_cached.pubkeys); + BOOST_CHECK(script_provider.scripts == script_provider_cached.scripts); + BOOST_CHECK(script_provider.origins == script_provider_cached.origins); + + // For each of the produced scripts, verify solvability, and when possible, try to sign a transaction spending it. for (size_t n = 0; n < spks.size(); ++n) { BOOST_CHECK_EQUAL(ref[n], HexStr(spks[n].begin(), spks[n].end())); BOOST_CHECK_EQUAL(IsSolvable(Merge(key_provider, script_provider), spks[n]), (flags & UNSOLVABLE) == 0); @@ -123,6 +146,7 @@ void Check(const std::string& prv, const std::string& pub, int flags, const std: } } } + // Verify no expected paths remain that were not observed. BOOST_CHECK_MESSAGE(left_paths.empty(), "Not all expected key paths found: " + prv); } |