diff options
Diffstat (limited to 'src/script')
-rw-r--r-- | src/script/bitcoinconsensus.cpp | 2 | ||||
-rw-r--r-- | src/script/bitcoinconsensus.h | 12 | ||||
-rw-r--r-- | src/script/descriptor.cpp | 531 | ||||
-rw-r--r-- | src/script/descriptor.h | 7 | ||||
-rw-r--r-- | src/script/interpreter.cpp | 54 | ||||
-rw-r--r-- | src/script/interpreter.h | 53 | ||||
-rw-r--r-- | src/script/sigcache.cpp | 16 | ||||
-rw-r--r-- | src/script/sigcache.h | 2 | ||||
-rw-r--r-- | src/script/sign.cpp | 213 | ||||
-rw-r--r-- | src/script/sign.h | 9 | ||||
-rw-r--r-- | src/script/signingprovider.cpp | 13 | ||||
-rw-r--r-- | src/script/signingprovider.h | 4 | ||||
-rw-r--r-- | src/script/standard.cpp | 251 | ||||
-rw-r--r-- | src/script/standard.h | 198 |
14 files changed, 1070 insertions, 295 deletions
diff --git a/src/script/bitcoinconsensus.cpp b/src/script/bitcoinconsensus.cpp index 76609f01a7..a9aa6a0060 100644 --- a/src/script/bitcoinconsensus.cpp +++ b/src/script/bitcoinconsensus.cpp @@ -92,7 +92,7 @@ static int verify_script(const unsigned char *scriptPubKey, unsigned int scriptP set_error(err, bitcoinconsensus_ERR_OK); PrecomputedTransactionData txdata(tx); - return VerifyScript(tx.vin[nIn].scriptSig, CScript(scriptPubKey, scriptPubKey + scriptPubKeyLen), &tx.vin[nIn].scriptWitness, flags, TransactionSignatureChecker(&tx, nIn, amount, txdata), nullptr); + return VerifyScript(tx.vin[nIn].scriptSig, CScript(scriptPubKey, scriptPubKey + scriptPubKeyLen), &tx.vin[nIn].scriptWitness, flags, TransactionSignatureChecker(&tx, nIn, amount, txdata, MissingDataBehavior::FAIL), nullptr); } catch (const std::exception&) { return set_error(err, bitcoinconsensus_ERR_TX_DESERIALIZE); // Error deserializing } diff --git a/src/script/bitcoinconsensus.h b/src/script/bitcoinconsensus.h index c5dceac848..b6939127e1 100644 --- a/src/script/bitcoinconsensus.h +++ b/src/script/bitcoinconsensus.h @@ -11,14 +11,12 @@ #if defined(BUILD_BITCOIN_INTERNAL) && defined(HAVE_CONFIG_H) #include <config/bitcoin-config.h> #if defined(_WIN32) - #if defined(DLL_EXPORT) - #if defined(HAVE_FUNC_ATTRIBUTE_DLLEXPORT) - #define EXPORT_SYMBOL __declspec(dllexport) - #else - #define EXPORT_SYMBOL - #endif + #if defined(HAVE_DLLEXPORT_ATTRIBUTE) + #define EXPORT_SYMBOL __declspec(dllexport) + #else + #define EXPORT_SYMBOL #endif - #elif defined(HAVE_FUNC_ATTRIBUTE_VISIBILITY) + #elif defined(HAVE_DEFAULT_VISIBILITY_ATTRIBUTE) #define EXPORT_SYMBOL __attribute__ ((visibility ("default"))) #endif #elif defined(MSC_VER) && !defined(STATIC_LIBBITCOINCONSENSUS) diff --git a/src/script/descriptor.cpp b/src/script/descriptor.cpp index 9e4b8a9dd6..84a8b06c5c 100644 --- a/src/script/descriptor.cpp +++ b/src/script/descriptor.cpp @@ -17,6 +17,7 @@ #include <util/vector.h> #include <memory> +#include <optional> #include <string> #include <vector> @@ -179,6 +180,9 @@ public: /** Get the descriptor string form including private data (if available in arg). */ virtual bool ToPrivateString(const SigningProvider& arg, std::string& out) const = 0; + /** Get the descriptor string form with the xpub at the last hardened derivation */ + virtual bool ToNormalizedString(const SigningProvider& arg, std::string& out, bool priv) const = 0; + /** Derive a private key, if private data is available in arg. */ virtual bool GetPrivKey(int pos, const SigningProvider& arg, CKey& key) const = 0; }; @@ -212,6 +216,21 @@ public: ret = "[" + OriginString() + "]" + std::move(sub); return true; } + bool ToNormalizedString(const SigningProvider& arg, std::string& ret, bool priv) const override + { + std::string sub; + if (!m_provider->ToNormalizedString(arg, sub, priv)) return false; + // If m_provider is a BIP32PubkeyProvider, we may get a string formatted like a OriginPubkeyProvider + // In that case, we need to strip out the leading square bracket and fingerprint from the substring, + // and append that to our own origin string. + if (sub[0] == '[') { + sub = sub.substr(9); + ret = "[" + OriginString() + std::move(sub); + } else { + ret = "[" + OriginString() + "]" + std::move(sub); + } + return true; + } bool GetPrivKey(int pos, const SigningProvider& arg, CKey& key) const override { return m_provider->GetPrivKey(pos, arg, key); @@ -222,9 +241,10 @@ public: class ConstPubkeyProvider final : public PubkeyProvider { CPubKey m_pubkey; + bool m_xonly; public: - ConstPubkeyProvider(uint32_t exp_index, const CPubKey& pubkey) : PubkeyProvider(exp_index), m_pubkey(pubkey) {} + ConstPubkeyProvider(uint32_t exp_index, const CPubKey& pubkey, bool xonly = false) : PubkeyProvider(exp_index), m_pubkey(pubkey), m_xonly(xonly) {} bool GetPubKey(int pos, const SigningProvider& arg, CPubKey& key, KeyOriginInfo& info, const DescriptorCache* read_cache = nullptr, DescriptorCache* write_cache = nullptr) override { key = m_pubkey; @@ -235,7 +255,7 @@ public: } bool IsRange() const override { return false; } size_t GetSize() const override { return m_pubkey.size(); } - std::string ToString() const override { return HexStr(m_pubkey); } + std::string ToString() const override { return m_xonly ? HexStr(m_pubkey).substr(2) : HexStr(m_pubkey); } bool ToPrivateString(const SigningProvider& arg, std::string& ret) const override { CKey key; @@ -243,6 +263,12 @@ public: ret = EncodeSecret(key); return true; } + bool ToNormalizedString(const SigningProvider& arg, std::string& ret, bool priv) const override + { + if (priv) return ToPrivateString(arg, ret); + ret = ToString(); + return true; + } bool GetPrivKey(int pos, const SigningProvider& arg, CKey& key) const override { return arg.GetKey(m_pubkey.GetID(), key); @@ -386,6 +412,56 @@ public: } return true; } + bool ToNormalizedString(const SigningProvider& arg, std::string& out, bool priv) const override + { + // For hardened derivation type, just return the typical string, nothing to normalize + if (m_derive == DeriveType::HARDENED) { + if (priv) return ToPrivateString(arg, out); + out = ToString(); + return true; + } + // Step backwards to find the last hardened step in the path + int i = (int)m_path.size() - 1; + for (; i >= 0; --i) { + if (m_path.at(i) >> 31) { + break; + } + } + // Either no derivation or all unhardened derivation + if (i == -1) { + if (priv) return ToPrivateString(arg, out); + out = ToString(); + return true; + } + // Derive the xpub at the last hardened step + CExtKey xprv; + if (!GetExtKey(arg, xprv)) return false; + KeyOriginInfo origin; + int k = 0; + for (; k <= i; ++k) { + // Derive + xprv.Derive(xprv, m_path.at(k)); + // Add to the path + origin.path.push_back(m_path.at(k)); + // First derivation element, get the fingerprint for origin + if (k == 0) { + std::copy(xprv.vchFingerprint, xprv.vchFingerprint + 4, origin.fingerprint); + } + } + // Build the remaining path + KeyPath end_path; + for (; k < (int)m_path.size(); ++k) { + end_path.push_back(m_path.at(k)); + } + // Build the string + std::string origin_str = HexStr(origin.fingerprint) + FormatHDKeypath(origin.path); + out = "[" + origin_str + "]" + (priv ? EncodeExtKey(xprv) : EncodeExtPubKey(xprv.Neuter())) + FormatHDKeypath(end_path); + if (IsRange()) { + out += "/*"; + assert(m_derive == DeriveType::UNHARDENED); + } + return true; + } bool GetPrivKey(int pos, const SigningProvider& arg, CKey& key) const override { CExtKey extkey; @@ -406,34 +482,36 @@ class DescriptorImpl : public Descriptor const std::string m_name; protected: - //! The sub-descriptor argument (nullptr for everything but SH and WSH). + //! The sub-descriptor arguments (empty for everything but SH and WSH). //! In doc/descriptors.m this is referred to as SCRIPT expressions sh(SCRIPT) //! and wsh(SCRIPT), and distinct from KEY expressions and ADDR expressions. - const std::unique_ptr<DescriptorImpl> m_subdescriptor_arg; + //! Subdescriptors can only ever generate a single script. + const std::vector<std::unique_ptr<DescriptorImpl>> m_subdescriptor_args; //! 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_subdescriptor_arg, or just once in case m_subdescriptor_arg is nullptr. - + * This function is invoked once by ExpandHelper. + * * @param pubkeys The evaluations of the m_pubkey_args field. - * @param script The evaluation of m_subdescriptor_arg (or nullptr when m_subdescriptor_arg is nullptr). + * @param scripts The evaluations of m_subdescriptor_args (one for each m_subdescriptor_args element). * @param out A FlatSigningProvider to put scripts or public keys in that are necessary to the solver. - * The script arguments to this function are automatically added, as is the origin info of the provided pubkeys. + * The origin info of the provided pubkeys is 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; + virtual std::vector<CScript> MakeScripts(const std::vector<CPubKey>& pubkeys, Span<const CScript> scripts, FlatSigningProvider& out) const = 0; public: - DescriptorImpl(std::vector<std::unique_ptr<PubkeyProvider>> pubkeys, std::unique_ptr<DescriptorImpl> script, const std::string& name) : m_pubkey_args(std::move(pubkeys)), m_name(name), m_subdescriptor_arg(std::move(script)) {} + DescriptorImpl(std::vector<std::unique_ptr<PubkeyProvider>> pubkeys, const std::string& name) : m_pubkey_args(std::move(pubkeys)), m_name(name), m_subdescriptor_args() {} + DescriptorImpl(std::vector<std::unique_ptr<PubkeyProvider>> pubkeys, std::unique_ptr<DescriptorImpl> script, const std::string& name) : m_pubkey_args(std::move(pubkeys)), m_name(name), m_subdescriptor_args(Vector(std::move(script))) {} + DescriptorImpl(std::vector<std::unique_ptr<PubkeyProvider>> pubkeys, std::vector<std::unique_ptr<DescriptorImpl>> scripts, const std::string& name) : m_pubkey_args(std::move(pubkeys)), m_name(name), m_subdescriptor_args(std::move(scripts)) {} bool IsSolvable() const override { - if (m_subdescriptor_arg) { - if (!m_subdescriptor_arg->IsSolvable()) return false; + for (const auto& arg : m_subdescriptor_args) { + if (!arg->IsSolvable()) return false; } return true; } @@ -443,13 +521,25 @@ public: for (const auto& pubkey : m_pubkey_args) { if (pubkey->IsRange()) return true; } - if (m_subdescriptor_arg) { - if (m_subdescriptor_arg->IsRange()) return true; + for (const auto& arg : m_subdescriptor_args) { + if (arg->IsRange()) return true; } return false; } - bool ToStringHelper(const SigningProvider* arg, std::string& out, bool priv) const + virtual bool ToStringSubScriptHelper(const SigningProvider* arg, std::string& ret, bool priv, bool normalized) const + { + size_t pos = 0; + for (const auto& scriptarg : m_subdescriptor_args) { + if (pos++) ret += ","; + std::string tmp; + if (!scriptarg->ToStringHelper(arg, tmp, priv, normalized)) return false; + ret += std::move(tmp); + } + return true; + } + + bool ToStringHelper(const SigningProvider* arg, std::string& out, bool priv, bool normalized) const { std::string extra = ToStringExtra(); size_t pos = extra.size() > 0 ? 1 : 0; @@ -457,33 +547,39 @@ public: for (const auto& pubkey : m_pubkey_args) { if (pos++) ret += ","; std::string tmp; - if (priv) { + if (normalized) { + if (!pubkey->ToNormalizedString(*arg, tmp, priv)) return false; + } else if (priv) { if (!pubkey->ToPrivateString(*arg, tmp)) return false; } else { tmp = pubkey->ToString(); } ret += std::move(tmp); } - if (m_subdescriptor_arg) { - if (pos++) ret += ","; - std::string tmp; - if (!m_subdescriptor_arg->ToStringHelper(arg, tmp, priv)) return false; - ret += std::move(tmp); - } - out = std::move(ret) + ")"; + std::string subscript; + if (!ToStringSubScriptHelper(arg, subscript, priv, normalized)) return false; + if (pos && subscript.size()) ret += ','; + out = std::move(ret) + std::move(subscript) + ")"; return true; } std::string ToString() const final { std::string ret; - ToStringHelper(nullptr, ret, false); + ToStringHelper(nullptr, ret, false, false); return AddChecksum(ret); } bool ToPrivateString(const SigningProvider& arg, std::string& out) const final { - bool ret = ToStringHelper(&arg, out, true); + bool ret = ToStringHelper(&arg, out, true, false); + out = AddChecksum(out); + return ret; + } + + bool ToNormalizedString(const SigningProvider& arg, std::string& out, bool priv) const override final + { + bool ret = ToStringHelper(&arg, out, priv, true); out = AddChecksum(out); return ret; } @@ -493,17 +589,20 @@ public: std::vector<std::pair<CPubKey, KeyOriginInfo>> entries; entries.reserve(m_pubkey_args.size()); - // Construct temporary data in `entries` and `subscripts`, to avoid producing output in case of failure. + // Construct temporary data in `entries`, `subscripts`, and `subprovider` 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, read_cache, write_cache)) return false; } std::vector<CScript> subscripts; - if (m_subdescriptor_arg) { - FlatSigningProvider subprovider; - if (!m_subdescriptor_arg->ExpandHelper(pos, arg, read_cache, subscripts, subprovider, write_cache)) return false; - out = Merge(out, subprovider); + FlatSigningProvider subprovider; + for (const auto& subarg : m_subdescriptor_args) { + std::vector<CScript> outscripts; + if (!subarg->ExpandHelper(pos, arg, read_cache, outscripts, subprovider, write_cache)) return false; + assert(outscripts.size() == 1); + subscripts.emplace_back(std::move(outscripts[0])); } + out = Merge(std::move(out), std::move(subprovider)); std::vector<CPubKey> pubkeys; pubkeys.reserve(entries.size()); @@ -511,17 +610,8 @@ public: pubkeys.push_back(entry.first); out.origins.emplace(entry.first.GetID(), std::make_pair<CPubKey, KeyOriginInfo>(CPubKey(entry.first), std::move(entry.second))); } - if (m_subdescriptor_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); - } + + output_scripts = MakeScripts(pubkeys, MakeSpan(subscripts), out); return true; } @@ -542,38 +632,42 @@ public: if (!p->GetPrivKey(pos, provider, key)) continue; out.keys.emplace(key.GetPubKey().GetID(), key); } - if (m_subdescriptor_arg) { - FlatSigningProvider subprovider; - m_subdescriptor_arg->ExpandPrivate(pos, provider, subprovider); - out = Merge(out, subprovider); + for (const auto& arg : m_subdescriptor_args) { + arg->ExpandPrivate(pos, provider, out); } } - Optional<OutputType> GetOutputType() const override { return nullopt; } + std::optional<OutputType> GetOutputType() const override { return std::nullopt; } }; +static std::optional<OutputType> OutputTypeFromDestination(const CTxDestination& dest) { + if (std::holds_alternative<PKHash>(dest) || + std::holds_alternative<ScriptHash>(dest)) { + return OutputType::LEGACY; + } + if (std::holds_alternative<WitnessV0KeyHash>(dest) || + std::holds_alternative<WitnessV0ScriptHash>(dest) || + std::holds_alternative<WitnessV1Taproot>(dest) || + std::holds_alternative<WitnessUnknown>(dest)) { + return OutputType::BECH32; + } + return std::nullopt; +} + /** 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 Vector(GetScriptForDestination(m_destination)); } + std::vector<CScript> MakeScripts(const std::vector<CPubKey>&, Span<const CScript>, FlatSigningProvider&) const override { return Vector(GetScriptForDestination(m_destination)); } public: - AddressDescriptor(CTxDestination destination) : DescriptorImpl({}, {}, "addr"), m_destination(std::move(destination)) {} + AddressDescriptor(CTxDestination destination) : DescriptorImpl({}, "addr"), m_destination(std::move(destination)) {} bool IsSolvable() const final { return false; } - Optional<OutputType> GetOutputType() const override + std::optional<OutputType> GetOutputType() const override { - switch (m_destination.index()) { - case 1 /* PKHash */: - case 2 /* ScriptHash */: return OutputType::LEGACY; - case 3 /* WitnessV0ScriptHash */: - case 4 /* WitnessV0KeyHash */: - case 5 /* WitnessUnknown */: return OutputType::BECH32; - case 0 /* CNoDestination */: - default: return nullopt; - } + return OutputTypeFromDestination(m_destination); } bool IsSingleType() const final { return true; } }; @@ -584,24 +678,16 @@ class RawDescriptor final : public DescriptorImpl const CScript m_script; protected: std::string ToStringExtra() const override { return HexStr(m_script); } - std::vector<CScript> MakeScripts(const std::vector<CPubKey>&, const CScript*, FlatSigningProvider&) const override { return Vector(m_script); } + std::vector<CScript> MakeScripts(const std::vector<CPubKey>&, Span<const CScript>, FlatSigningProvider&) const override { return Vector(m_script); } public: - RawDescriptor(CScript script) : DescriptorImpl({}, {}, "raw"), m_script(std::move(script)) {} + RawDescriptor(CScript script) : DescriptorImpl({}, "raw"), m_script(std::move(script)) {} bool IsSolvable() const final { return false; } - Optional<OutputType> GetOutputType() const override + std::optional<OutputType> GetOutputType() const override { CTxDestination dest; ExtractDestination(m_script, dest); - switch (dest.index()) { - case 1 /* PKHash */: - case 2 /* ScriptHash */: return OutputType::LEGACY; - case 3 /* WitnessV0ScriptHash */: - case 4 /* WitnessV0KeyHash */: - case 5 /* WitnessUnknown */: return OutputType::BECH32; - case 0 /* CNoDestination */: - default: return nullopt; - } + return OutputTypeFromDestination(dest); } bool IsSingleType() const final { return true; } }; @@ -609,10 +695,20 @@ public: /** A parsed pk(P) descriptor. */ class PKDescriptor final : public DescriptorImpl { +private: + const bool m_xonly; protected: - std::vector<CScript> MakeScripts(const std::vector<CPubKey>& keys, const CScript*, FlatSigningProvider&) const override { return Vector(GetScriptForRawPubKey(keys[0])); } + std::vector<CScript> MakeScripts(const std::vector<CPubKey>& keys, Span<const CScript>, FlatSigningProvider&) const override + { + if (m_xonly) { + CScript script = CScript() << ToByteVector(XOnlyPubKey(keys[0])) << OP_CHECKSIG; + return Vector(std::move(script)); + } else { + return Vector(GetScriptForRawPubKey(keys[0])); + } + } public: - PKDescriptor(std::unique_ptr<PubkeyProvider> prov) : DescriptorImpl(Vector(std::move(prov)), {}, "pk") {} + PKDescriptor(std::unique_ptr<PubkeyProvider> prov, bool xonly = false) : DescriptorImpl(Vector(std::move(prov)), "pk"), m_xonly(xonly) {} bool IsSingleType() const final { return true; } }; @@ -620,15 +716,15 @@ public: class PKHDescriptor final : public DescriptorImpl { protected: - std::vector<CScript> MakeScripts(const std::vector<CPubKey>& keys, const CScript*, FlatSigningProvider& out) const override + std::vector<CScript> MakeScripts(const std::vector<CPubKey>& keys, Span<const CScript>, FlatSigningProvider& out) const override { CKeyID id = keys[0].GetID(); out.pubkeys.emplace(id, keys[0]); return Vector(GetScriptForDestination(PKHash(id))); } public: - PKHDescriptor(std::unique_ptr<PubkeyProvider> prov) : DescriptorImpl(Vector(std::move(prov)), {}, "pkh") {} - Optional<OutputType> GetOutputType() const override { return OutputType::LEGACY; } + PKHDescriptor(std::unique_ptr<PubkeyProvider> prov) : DescriptorImpl(Vector(std::move(prov)), "pkh") {} + std::optional<OutputType> GetOutputType() const override { return OutputType::LEGACY; } bool IsSingleType() const final { return true; } }; @@ -636,15 +732,15 @@ public: class WPKHDescriptor final : public DescriptorImpl { protected: - std::vector<CScript> MakeScripts(const std::vector<CPubKey>& keys, const CScript*, FlatSigningProvider& out) const override + std::vector<CScript> MakeScripts(const std::vector<CPubKey>& keys, Span<const CScript>, FlatSigningProvider& out) const override { CKeyID id = keys[0].GetID(); out.pubkeys.emplace(id, keys[0]); return Vector(GetScriptForDestination(WitnessV0KeyHash(id))); } public: - WPKHDescriptor(std::unique_ptr<PubkeyProvider> prov) : DescriptorImpl(Vector(std::move(prov)), {}, "wpkh") {} - Optional<OutputType> GetOutputType() const override { return OutputType::BECH32; } + WPKHDescriptor(std::unique_ptr<PubkeyProvider> prov) : DescriptorImpl(Vector(std::move(prov)), "wpkh") {} + std::optional<OutputType> GetOutputType() const override { return OutputType::BECH32; } bool IsSingleType() const final { return true; } }; @@ -652,7 +748,7 @@ public: class ComboDescriptor final : public DescriptorImpl { protected: - std::vector<CScript> MakeScripts(const std::vector<CPubKey>& keys, const CScript*, FlatSigningProvider& out) const override + std::vector<CScript> MakeScripts(const std::vector<CPubKey>& keys, Span<const CScript>, FlatSigningProvider& out) const override { std::vector<CScript> ret; CKeyID id = keys[0].GetID(); @@ -668,7 +764,7 @@ protected: return ret; } public: - ComboDescriptor(std::unique_ptr<PubkeyProvider> prov) : DescriptorImpl(Vector(std::move(prov)), {}, "combo") {} + ComboDescriptor(std::unique_ptr<PubkeyProvider> prov) : DescriptorImpl(Vector(std::move(prov)), "combo") {} bool IsSingleType() const final { return false; } }; @@ -679,7 +775,7 @@ class MultisigDescriptor final : public DescriptorImpl const bool m_sorted; 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 { + std::vector<CScript> MakeScripts(const std::vector<CPubKey>& keys, Span<const CScript>, FlatSigningProvider&) const override { if (m_sorted) { std::vector<CPubKey> sorted_keys(keys); std::sort(sorted_keys.begin(), sorted_keys.end()); @@ -688,7 +784,7 @@ protected: return Vector(GetScriptForMultisig(m_threshold, keys)); } public: - MultisigDescriptor(int threshold, std::vector<std::unique_ptr<PubkeyProvider>> providers, bool sorted = false) : DescriptorImpl(std::move(providers), {}, sorted ? "sortedmulti" : "multi"), m_threshold(threshold), m_sorted(sorted) {} + MultisigDescriptor(int threshold, std::vector<std::unique_ptr<PubkeyProvider>> providers, bool sorted = false) : DescriptorImpl(std::move(providers), sorted ? "sortedmulti" : "multi"), m_threshold(threshold), m_sorted(sorted) {} bool IsSingleType() const final { return true; } }; @@ -696,14 +792,19 @@ public: class SHDescriptor final : public DescriptorImpl { protected: - std::vector<CScript> MakeScripts(const std::vector<CPubKey>&, const CScript* script, FlatSigningProvider&) const override { return Vector(GetScriptForDestination(ScriptHash(*script))); } + std::vector<CScript> MakeScripts(const std::vector<CPubKey>&, Span<const CScript> scripts, FlatSigningProvider& out) const override + { + auto ret = Vector(GetScriptForDestination(ScriptHash(scripts[0]))); + if (ret.size()) out.scripts.emplace(CScriptID(scripts[0]), scripts[0]); + return ret; + } public: SHDescriptor(std::unique_ptr<DescriptorImpl> desc) : DescriptorImpl({}, std::move(desc), "sh") {} - Optional<OutputType> GetOutputType() const override + std::optional<OutputType> GetOutputType() const override { - assert(m_subdescriptor_arg); - if (m_subdescriptor_arg->GetOutputType() == OutputType::BECH32) return OutputType::P2SH_SEGWIT; + assert(m_subdescriptor_args.size() == 1); + if (m_subdescriptor_args[0]->GetOutputType() == OutputType::BECH32) return OutputType::P2SH_SEGWIT; return OutputType::LEGACY; } bool IsSingleType() const final { return true; } @@ -713,10 +814,67 @@ public: class WSHDescriptor final : public DescriptorImpl { protected: - std::vector<CScript> MakeScripts(const std::vector<CPubKey>&, const CScript* script, FlatSigningProvider&) const override { return Vector(GetScriptForDestination(WitnessV0ScriptHash(*script))); } + std::vector<CScript> MakeScripts(const std::vector<CPubKey>&, Span<const CScript> scripts, FlatSigningProvider& out) const override + { + auto ret = Vector(GetScriptForDestination(WitnessV0ScriptHash(scripts[0]))); + if (ret.size()) out.scripts.emplace(CScriptID(scripts[0]), scripts[0]); + return ret; + } public: WSHDescriptor(std::unique_ptr<DescriptorImpl> desc) : DescriptorImpl({}, std::move(desc), "wsh") {} - Optional<OutputType> GetOutputType() const override { return OutputType::BECH32; } + std::optional<OutputType> GetOutputType() const override { return OutputType::BECH32; } + bool IsSingleType() const final { return true; } +}; + +/** A parsed tr(...) descriptor. */ +class TRDescriptor final : public DescriptorImpl +{ + std::vector<int> m_depths; +protected: + std::vector<CScript> MakeScripts(const std::vector<CPubKey>& keys, Span<const CScript> scripts, FlatSigningProvider& out) const override + { + TaprootBuilder builder; + assert(m_depths.size() == scripts.size()); + for (size_t pos = 0; pos < m_depths.size(); ++pos) { + builder.Add(m_depths[pos], scripts[pos], TAPROOT_LEAF_TAPSCRIPT); + } + if (!builder.IsComplete()) return {}; + assert(keys.size() == 1); + XOnlyPubKey xpk(keys[0]); + if (!xpk.IsFullyValid()) return {}; + builder.Finalize(xpk); + WitnessV1Taproot output = builder.GetOutput(); + out.tr_spenddata[output].Merge(builder.GetSpendData()); + return Vector(GetScriptForDestination(output)); + } + bool ToStringSubScriptHelper(const SigningProvider* arg, std::string& ret, bool priv, bool normalized) const override + { + if (m_depths.empty()) return true; + std::vector<bool> path; + for (size_t pos = 0; pos < m_depths.size(); ++pos) { + if (pos) ret += ','; + while ((int)path.size() <= m_depths[pos]) { + if (path.size()) ret += '{'; + path.push_back(false); + } + std::string tmp; + if (!m_subdescriptor_args[pos]->ToStringHelper(arg, tmp, priv, normalized)) return false; + ret += std::move(tmp); + while (!path.empty() && path.back()) { + if (path.size() > 1) ret += '}'; + path.pop_back(); + } + if (!path.empty()) path.back() = true; + } + return true; + } +public: + TRDescriptor(std::unique_ptr<PubkeyProvider> internal_key, std::vector<std::unique_ptr<DescriptorImpl>> descs, std::vector<int> depths) : + DescriptorImpl(Vector(std::move(internal_key)), std::move(descs), "tr"), m_depths(std::move(depths)) + { + assert(m_subdescriptor_args.size() == m_depths.size()); + } + std::optional<OutputType> GetOutputType() const override { return OutputType::BECH32; } bool IsSingleType() const final { return true; } }; @@ -725,9 +883,11 @@ public: //////////////////////////////////////////////////////////////////////////// enum class ParseScriptContext { - TOP, - P2SH, - P2WSH, + TOP, //!< Top-level context (script goes directly in scriptPubKey) + P2SH, //!< Inside sh() (script becomes P2SH redeemScript) + P2WPKH, //!< Inside wpkh() (no script, pubkey only) + P2WSH, //!< Inside wsh() (script becomes v0 witness script) + P2TR, //!< Inside tr() (either internal key, or BIP342 script leaf) }; /** Parse a key path, being passed a split list of elements (the first element is ignored). */ @@ -754,10 +914,11 @@ enum class ParseScriptContext { } /** Parse a public key that excludes origin information. */ -std::unique_ptr<PubkeyProvider> ParsePubkeyInner(uint32_t key_exp_index, const Span<const char>& sp, bool permit_uncompressed, FlatSigningProvider& out, std::string& error) +std::unique_ptr<PubkeyProvider> ParsePubkeyInner(uint32_t key_exp_index, const Span<const char>& sp, ParseScriptContext ctx, FlatSigningProvider& out, std::string& error) { using namespace spanparsing; + bool permit_uncompressed = ctx == ParseScriptContext::TOP || ctx == ParseScriptContext::P2SH; auto split = Split(sp, '/'); std::string str(split[0].begin(), split[0].end()); if (str.size() == 0) { @@ -770,11 +931,18 @@ std::unique_ptr<PubkeyProvider> ParsePubkeyInner(uint32_t key_exp_index, const S CPubKey pubkey(data); if (pubkey.IsFullyValid()) { if (permit_uncompressed || pubkey.IsCompressed()) { - return MakeUnique<ConstPubkeyProvider>(key_exp_index, pubkey); + return std::make_unique<ConstPubkeyProvider>(key_exp_index, pubkey); } else { error = "Uncompressed keys are not allowed"; return nullptr; } + } else if (data.size() == 32 && ctx == ParseScriptContext::P2TR) { + unsigned char fullkey[33] = {0x02}; + std::copy(data.begin(), data.end(), fullkey + 1); + pubkey.Set(std::begin(fullkey), std::end(fullkey)); + if (pubkey.IsFullyValid()) { + return std::make_unique<ConstPubkeyProvider>(key_exp_index, pubkey, true); + } } error = strprintf("Pubkey '%s' is invalid", str); return nullptr; @@ -784,7 +952,7 @@ std::unique_ptr<PubkeyProvider> ParsePubkeyInner(uint32_t key_exp_index, const S if (permit_uncompressed || key.IsCompressed()) { CPubKey pubkey = key.GetPubKey(); out.keys.emplace(pubkey.GetID(), key); - return MakeUnique<ConstPubkeyProvider>(key_exp_index, pubkey); + return std::make_unique<ConstPubkeyProvider>(key_exp_index, pubkey); } else { error = "Uncompressed keys are not allowed"; return nullptr; @@ -811,11 +979,11 @@ std::unique_ptr<PubkeyProvider> ParsePubkeyInner(uint32_t key_exp_index, const S extpubkey = extkey.Neuter(); out.keys.emplace(extpubkey.pubkey.GetID(), extkey.key); } - return MakeUnique<BIP32PubkeyProvider>(key_exp_index, extpubkey, std::move(path), type); + return std::make_unique<BIP32PubkeyProvider>(key_exp_index, extpubkey, std::move(path), type); } /** Parse a public key including origin information (if enabled). */ -std::unique_ptr<PubkeyProvider> ParsePubkey(uint32_t key_exp_index, const Span<const char>& sp, bool permit_uncompressed, FlatSigningProvider& out, std::string& error) +std::unique_ptr<PubkeyProvider> ParsePubkey(uint32_t key_exp_index, const Span<const char>& sp, ParseScriptContext ctx, FlatSigningProvider& out, std::string& error) { using namespace spanparsing; @@ -824,7 +992,7 @@ std::unique_ptr<PubkeyProvider> ParsePubkey(uint32_t key_exp_index, const Span<c error = "Multiple ']' characters found for a single pubkey"; return nullptr; } - if (origin_split.size() == 1) return ParsePubkeyInner(key_exp_index, origin_split[0], permit_uncompressed, out, error); + if (origin_split.size() == 1) return ParsePubkeyInner(key_exp_index, origin_split[0], ctx, out, error); if (origin_split[0].empty() || origin_split[0][0] != '[') { error = strprintf("Key origin start '[ character expected but not found, got '%c' instead", origin_split[0].empty() ? /** empty, implies split char */ ']' : origin_split[0][0]); @@ -846,37 +1014,43 @@ std::unique_ptr<PubkeyProvider> ParsePubkey(uint32_t key_exp_index, const Span<c assert(fpr_bytes.size() == 4); std::copy(fpr_bytes.begin(), fpr_bytes.end(), info.fingerprint); if (!ParseKeyPath(slash_split, info.path, error)) return nullptr; - auto provider = ParsePubkeyInner(key_exp_index, origin_split[1], permit_uncompressed, out, error); + auto provider = ParsePubkeyInner(key_exp_index, origin_split[1], ctx, out, error); if (!provider) return nullptr; - return MakeUnique<OriginPubkeyProvider>(key_exp_index, std::move(info), std::move(provider)); + return std::make_unique<OriginPubkeyProvider>(key_exp_index, std::move(info), std::move(provider)); } /** Parse a script in a particular context. */ -std::unique_ptr<DescriptorImpl> ParseScript(uint32_t key_exp_index, Span<const char>& sp, ParseScriptContext ctx, FlatSigningProvider& out, std::string& error) +std::unique_ptr<DescriptorImpl> ParseScript(uint32_t& key_exp_index, Span<const char>& sp, ParseScriptContext ctx, FlatSigningProvider& out, std::string& error) { using namespace spanparsing; auto expr = Expr(sp); bool sorted_multi = false; if (Func("pk", expr)) { - auto pubkey = ParsePubkey(key_exp_index, expr, ctx != ParseScriptContext::P2WSH, out, error); + auto pubkey = ParsePubkey(key_exp_index, expr, ctx, out, error); if (!pubkey) return nullptr; - return MakeUnique<PKDescriptor>(std::move(pubkey)); + ++key_exp_index; + return std::make_unique<PKDescriptor>(std::move(pubkey), ctx == ParseScriptContext::P2TR); } - if (Func("pkh", expr)) { - auto pubkey = ParsePubkey(key_exp_index, expr, ctx != ParseScriptContext::P2WSH, out, error); + if ((ctx == ParseScriptContext::TOP || ctx == ParseScriptContext::P2SH || ctx == ParseScriptContext::P2WSH) && Func("pkh", expr)) { + auto pubkey = ParsePubkey(key_exp_index, expr, ctx, out, error); if (!pubkey) return nullptr; - return MakeUnique<PKHDescriptor>(std::move(pubkey)); + ++key_exp_index; + return std::make_unique<PKHDescriptor>(std::move(pubkey)); + } else if (Func("pkh", expr)) { + error = "Can only have pkh at top level, in sh(), or in wsh()"; + return nullptr; } if (ctx == ParseScriptContext::TOP && Func("combo", expr)) { - auto pubkey = ParsePubkey(key_exp_index, expr, true, out, error); + auto pubkey = ParsePubkey(key_exp_index, expr, ctx, out, error); if (!pubkey) return nullptr; - return MakeUnique<ComboDescriptor>(std::move(pubkey)); - } else if (ctx != ParseScriptContext::TOP && Func("combo", expr)) { - error = "Cannot have combo in non-top level"; + ++key_exp_index; + return std::make_unique<ComboDescriptor>(std::move(pubkey)); + } else if (Func("combo", expr)) { + error = "Can only have combo() at top level"; return nullptr; } - if ((sorted_multi = Func("sortedmulti", expr)) || Func("multi", expr)) { + if ((ctx == ParseScriptContext::TOP || ctx == ParseScriptContext::P2SH || ctx == ParseScriptContext::P2WSH) && ((sorted_multi = Func("sortedmulti", expr)) || Func("multi", expr))) { auto threshold = Expr(expr); uint32_t thres; std::vector<std::unique_ptr<PubkeyProvider>> providers; @@ -891,14 +1065,14 @@ std::unique_ptr<DescriptorImpl> ParseScript(uint32_t key_exp_index, Span<const c return nullptr; } auto arg = Expr(expr); - auto pk = ParsePubkey(key_exp_index, arg, ctx != ParseScriptContext::P2WSH, out, error); + auto pk = ParsePubkey(key_exp_index, arg, ctx, out, error); if (!pk) return nullptr; script_size += pk->GetSize() + 1; providers.emplace_back(std::move(pk)); key_exp_index++; } - if (providers.empty() || providers.size() > 16) { - error = strprintf("Cannot have %u keys in multisig; must have between 1 and 16 keys, inclusive", providers.size()); + if (providers.empty() || providers.size() > MAX_PUBKEYS_PER_MULTISIG) { + error = strprintf("Cannot have %u keys in multisig; must have between 1 and %d keys, inclusive", providers.size(), MAX_PUBKEYS_PER_MULTISIG); return nullptr; } else if (thres < 1) { error = strprintf("Multisig threshold cannot be %d, must be at least 1", thres); @@ -914,35 +1088,40 @@ std::unique_ptr<DescriptorImpl> ParseScript(uint32_t key_exp_index, Span<const c } } if (ctx == ParseScriptContext::P2SH) { + // This limits the maximum number of compressed pubkeys to 15. if (script_size + 3 > MAX_SCRIPT_ELEMENT_SIZE) { error = strprintf("P2SH script is too large, %d bytes is larger than %d bytes", script_size + 3, MAX_SCRIPT_ELEMENT_SIZE); return nullptr; } } - return MakeUnique<MultisigDescriptor>(thres, std::move(providers), sorted_multi); + return std::make_unique<MultisigDescriptor>(thres, std::move(providers), sorted_multi); + } else if (Func("sortedmulti", expr) || Func("multi", expr)) { + error = "Can only have multi/sortedmulti at top level, in sh(), or in wsh()"; + return nullptr; } - if (ctx != ParseScriptContext::P2WSH && Func("wpkh", expr)) { - auto pubkey = ParsePubkey(key_exp_index, expr, false, out, error); + if ((ctx == ParseScriptContext::TOP || ctx == ParseScriptContext::P2SH) && Func("wpkh", expr)) { + auto pubkey = ParsePubkey(key_exp_index, expr, ParseScriptContext::P2WPKH, out, error); if (!pubkey) return nullptr; - return MakeUnique<WPKHDescriptor>(std::move(pubkey)); - } else if (ctx == ParseScriptContext::P2WSH && Func("wpkh", expr)) { - error = "Cannot have wpkh within wsh"; + key_exp_index++; + return std::make_unique<WPKHDescriptor>(std::move(pubkey)); + } else if (Func("wpkh", expr)) { + error = "Can only have wpkh() at top level or inside sh()"; return nullptr; } if (ctx == ParseScriptContext::TOP && Func("sh", expr)) { auto desc = ParseScript(key_exp_index, expr, ParseScriptContext::P2SH, out, error); if (!desc || expr.size()) return nullptr; - return MakeUnique<SHDescriptor>(std::move(desc)); - } else if (ctx != ParseScriptContext::TOP && Func("sh", expr)) { - error = "Cannot have sh in non-top level"; + return std::make_unique<SHDescriptor>(std::move(desc)); + } else if (Func("sh", expr)) { + error = "Can only have sh() at top level"; return nullptr; } - if (ctx != ParseScriptContext::P2WSH && Func("wsh", expr)) { + if ((ctx == ParseScriptContext::TOP || ctx == ParseScriptContext::P2SH) && Func("wsh", expr)) { auto desc = ParseScript(key_exp_index, expr, ParseScriptContext::P2WSH, out, error); if (!desc || expr.size()) return nullptr; - return MakeUnique<WSHDescriptor>(std::move(desc)); - } else if (ctx == ParseScriptContext::P2WSH && Func("wsh", expr)) { - error = "Cannot have wsh within wsh"; + return std::make_unique<WSHDescriptor>(std::move(desc)); + } else if (Func("wsh", expr)) { + error = "Can only have wsh() at top level or inside sh()"; return nullptr; } if (ctx == ParseScriptContext::TOP && Func("addr", expr)) { @@ -951,7 +1130,71 @@ std::unique_ptr<DescriptorImpl> ParseScript(uint32_t key_exp_index, Span<const c error = "Address is not valid"; return nullptr; } - return MakeUnique<AddressDescriptor>(std::move(dest)); + return std::make_unique<AddressDescriptor>(std::move(dest)); + } else if (Func("addr", expr)) { + error = "Can only have addr() at top level"; + return nullptr; + } + if (ctx == ParseScriptContext::TOP && Func("tr", expr)) { + auto arg = Expr(expr); + auto internal_key = ParsePubkey(key_exp_index, arg, ParseScriptContext::P2TR, out, error); + if (!internal_key) return nullptr; + ++key_exp_index; + std::vector<std::unique_ptr<DescriptorImpl>> subscripts; //!< list of script subexpressions + std::vector<int> depths; //!< depth in the tree of each subexpression (same length subscripts) + if (expr.size()) { + if (!Const(",", expr)) { + error = strprintf("tr: expected ',', got '%c'", expr[0]); + return nullptr; + } + /** The path from the top of the tree to what we're currently processing. + * branches[i] == false: left branch in the i'th step from the top; true: right branch. + */ + std::vector<bool> branches; + // Loop over all provided scripts. In every iteration exactly one script will be processed. + // Use a do-loop because inside this if-branch we expect at least one script. + do { + // First process all open braces. + while (Const("{", expr)) { + branches.push_back(false); // new left branch + if (branches.size() > TAPROOT_CONTROL_MAX_NODE_COUNT) { + error = strprintf("tr() supports at most %i nesting levels", TAPROOT_CONTROL_MAX_NODE_COUNT); + return nullptr; + } + } + // Process the actual script expression. + auto sarg = Expr(expr); + subscripts.emplace_back(ParseScript(key_exp_index, sarg, ParseScriptContext::P2TR, out, error)); + if (!subscripts.back()) return nullptr; + depths.push_back(branches.size()); + // Process closing braces; one is expected for every right branch we were in. + while (branches.size() && branches.back()) { + if (!Const("}", expr)) { + error = strprintf("tr(): expected '}' after script expression"); + return nullptr; + } + branches.pop_back(); // move up one level after encountering '}' + } + // If after that, we're at the end of a left branch, expect a comma. + if (branches.size() && !branches.back()) { + if (!Const(",", expr)) { + error = strprintf("tr(): expected ',' after script expression"); + return nullptr; + } + branches.back() = true; // And now we're in a right branch. + } + } while (branches.size()); + // After we've explored a whole tree, we must be at the end of the expression. + if (expr.size()) { + error = strprintf("tr(): expected ')' after script expression"); + return nullptr; + } + } + assert(TaprootBuilder::ValidDepths(depths)); + return std::make_unique<TRDescriptor>(std::move(internal_key), std::move(subscripts), std::move(depths)); + } else if (Func("tr", expr)) { + error = "Can only have tr at top level"; + return nullptr; } if (ctx == ParseScriptContext::TOP && Func("raw", expr)) { std::string str(expr.begin(), expr.end()); @@ -960,7 +1203,10 @@ std::unique_ptr<DescriptorImpl> ParseScript(uint32_t key_exp_index, Span<const c return nullptr; } auto bytes = ParseHex(str); - return MakeUnique<RawDescriptor>(CScript(bytes.begin(), bytes.end())); + return std::make_unique<RawDescriptor>(CScript(bytes.begin(), bytes.end())); + } else if (Func("raw", expr)) { + error = "Can only have raw() at top level"; + return nullptr; } if (ctx == ParseScriptContext::P2SH) { error = "A function is needed within P2SH"; @@ -975,10 +1221,10 @@ std::unique_ptr<DescriptorImpl> ParseScript(uint32_t key_exp_index, Span<const c std::unique_ptr<PubkeyProvider> InferPubkey(const CPubKey& pubkey, ParseScriptContext, const SigningProvider& provider) { - std::unique_ptr<PubkeyProvider> key_provider = MakeUnique<ConstPubkeyProvider>(0, pubkey); + std::unique_ptr<PubkeyProvider> key_provider = std::make_unique<ConstPubkeyProvider>(0, pubkey); KeyOriginInfo info; if (provider.GetKeyOrigin(pubkey.GetID(), info)) { - return MakeUnique<OriginPubkeyProvider>(0, std::move(info), std::move(key_provider)); + return std::make_unique<OriginPubkeyProvider>(0, std::move(info), std::move(key_provider)); } return key_provider; } @@ -989,9 +1235,9 @@ std::unique_ptr<DescriptorImpl> InferScript(const CScript& script, ParseScriptCo TxoutType txntype = Solver(script, data); if (txntype == TxoutType::PUBKEY) { - CPubKey pubkey(data[0].begin(), data[0].end()); + CPubKey pubkey(data[0]); if (pubkey.IsValid()) { - return MakeUnique<PKDescriptor>(InferPubkey(pubkey, ctx, provider)); + return std::make_unique<PKDescriptor>(InferPubkey(pubkey, ctx, provider)); } } if (txntype == TxoutType::PUBKEYHASH) { @@ -999,7 +1245,7 @@ std::unique_ptr<DescriptorImpl> InferScript(const CScript& script, ParseScriptCo CKeyID keyid(hash); CPubKey pubkey; if (provider.GetPubKey(keyid, pubkey)) { - return MakeUnique<PKHDescriptor>(InferPubkey(pubkey, ctx, provider)); + return std::make_unique<PKHDescriptor>(InferPubkey(pubkey, ctx, provider)); } } if (txntype == TxoutType::WITNESS_V0_KEYHASH && ctx != ParseScriptContext::P2WSH) { @@ -1007,16 +1253,16 @@ std::unique_ptr<DescriptorImpl> InferScript(const CScript& script, ParseScriptCo CKeyID keyid(hash); CPubKey pubkey; if (provider.GetPubKey(keyid, pubkey)) { - return MakeUnique<WPKHDescriptor>(InferPubkey(pubkey, ctx, provider)); + return std::make_unique<WPKHDescriptor>(InferPubkey(pubkey, ctx, provider)); } } if (txntype == TxoutType::MULTISIG) { std::vector<std::unique_ptr<PubkeyProvider>> providers; for (size_t i = 1; i + 1 < data.size(); ++i) { - CPubKey pubkey(data[i].begin(), data[i].end()); + CPubKey pubkey(data[i]); providers.push_back(InferPubkey(pubkey, ctx, provider)); } - return MakeUnique<MultisigDescriptor>((int)data[0][0], std::move(providers)); + return std::make_unique<MultisigDescriptor>((int)data[0][0], std::move(providers)); } if (txntype == TxoutType::SCRIPTHASH && ctx == ParseScriptContext::TOP) { uint160 hash(data[0]); @@ -1024,7 +1270,7 @@ std::unique_ptr<DescriptorImpl> InferScript(const CScript& script, ParseScriptCo CScript subscript; if (provider.GetCScript(scriptid, subscript)) { auto sub = InferScript(subscript, ParseScriptContext::P2SH, provider); - if (sub) return MakeUnique<SHDescriptor>(std::move(sub)); + if (sub) return std::make_unique<SHDescriptor>(std::move(sub)); } } if (txntype == TxoutType::WITNESS_V0_SCRIPTHASH && ctx != ParseScriptContext::P2WSH) { @@ -1033,18 +1279,18 @@ std::unique_ptr<DescriptorImpl> InferScript(const CScript& script, ParseScriptCo CScript subscript; if (provider.GetCScript(scriptid, subscript)) { auto sub = InferScript(subscript, ParseScriptContext::P2WSH, provider); - if (sub) return MakeUnique<WSHDescriptor>(std::move(sub)); + if (sub) return std::make_unique<WSHDescriptor>(std::move(sub)); } } CTxDestination dest; if (ExtractDestination(script, dest)) { if (GetScriptForDestination(dest) == script) { - return MakeUnique<AddressDescriptor>(std::move(dest)); + return std::make_unique<AddressDescriptor>(std::move(dest)); } } - return MakeUnique<RawDescriptor>(script); + return std::make_unique<RawDescriptor>(script); } @@ -1090,7 +1336,8 @@ std::unique_ptr<Descriptor> Parse(const std::string& descriptor, FlatSigningProv { Span<const char> sp{descriptor}; if (!CheckChecksum(sp, require_checksum, error)) return nullptr; - auto ret = ParseScript(0, sp, ParseScriptContext::TOP, out, error); + uint32_t key_exp_index = 0; + auto ret = ParseScript(key_exp_index, sp, ParseScriptContext::TOP, out, error); 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 17b43e7c81..332ae2f230 100644 --- a/src/script/descriptor.h +++ b/src/script/descriptor.h @@ -5,12 +5,12 @@ #ifndef BITCOIN_SCRIPT_DESCRIPTOR_H #define BITCOIN_SCRIPT_DESCRIPTOR_H -#include <optional.h> #include <outputtype.h> #include <script/script.h> #include <script/sign.h> #include <script/signingprovider.h> +#include <optional> #include <vector> using ExtPubKeyMap = std::unordered_map<uint32_t, CExtPubKey>; @@ -93,6 +93,9 @@ struct Descriptor { /** Convert the descriptor to a private string. This fails if the provided provider does not have the relevant private keys. */ virtual bool ToPrivateString(const SigningProvider& provider, std::string& out) const = 0; + /** Convert the descriptor to a normalized string. Normalized descriptors have the xpub at the last hardened step. This fails if the provided provider does not have the private keys to derive that xpub. */ + virtual bool ToNormalizedString(const SigningProvider& provider, std::string& out, bool priv) const = 0; + /** Expand a descriptor at a specified position. * * @param[in] pos The position at which to expand the descriptor. If IsRange() is false, this is ignored. @@ -121,7 +124,7 @@ struct Descriptor { virtual void ExpandPrivate(int pos, const SigningProvider& provider, FlatSigningProvider& out) const = 0; /** @return The OutputType of the scriptPubKey(s) produced by this descriptor. Or nullopt if indeterminate (multiple or none) */ - virtual Optional<OutputType> GetOutputType() const = 0; + virtual std::optional<OutputType> GetOutputType() const = 0; }; /** Parse a `descriptor` string. Included private keys are put in `out`. diff --git a/src/script/interpreter.cpp b/src/script/interpreter.cpp index ecac3b9e7e..2dd173ee20 100644 --- a/src/script/interpreter.cpp +++ b/src/script/interpreter.cpp @@ -225,7 +225,7 @@ bool static CheckPubKeyEncoding(const valtype &vchPubKey, unsigned int flags, co return true; } -bool static CheckMinimalPush(const valtype& data, opcodetype opcode) { +bool CheckMinimalPush(const valtype& data, opcodetype opcode) { // Excludes OP_1NEGATE, OP_1-16 since they are by definition minimal assert(0 <= opcode && opcode <= OP_PUSHDATA4); if (data.size() == 0) { @@ -1420,7 +1420,7 @@ uint256 GetSpentScriptsSHA256(const std::vector<CTxOut>& outputs_spent) } // namespace template <class T> -void PrecomputedTransactionData::Init(const T& txTo, std::vector<CTxOut>&& spent_outputs) +void PrecomputedTransactionData::Init(const T& txTo, std::vector<CTxOut>&& spent_outputs, bool force) { assert(!m_spent_outputs_ready); @@ -1431,9 +1431,9 @@ void PrecomputedTransactionData::Init(const T& txTo, std::vector<CTxOut>&& spent } // Determine which precomputation-impacting features this transaction uses. - bool uses_bip143_segwit = false; - bool uses_bip341_taproot = false; - for (size_t inpos = 0; inpos < txTo.vin.size(); ++inpos) { + bool uses_bip143_segwit = force; + bool uses_bip341_taproot = force; + for (size_t inpos = 0; inpos < txTo.vin.size() && !(uses_bip143_segwit && uses_bip341_taproot); ++inpos) { if (!txTo.vin[inpos].scriptWitness.IsNull()) { if (m_spent_outputs_ready && m_spent_outputs[inpos].scriptPubKey.size() == 2 + WITNESS_V1_TAPROOT_SIZE && m_spent_outputs[inpos].scriptPubKey[0] == OP_1) { @@ -1478,18 +1478,29 @@ PrecomputedTransactionData::PrecomputedTransactionData(const T& txTo) } // explicit instantiation -template void PrecomputedTransactionData::Init(const CTransaction& txTo, std::vector<CTxOut>&& spent_outputs); -template void PrecomputedTransactionData::Init(const CMutableTransaction& txTo, std::vector<CTxOut>&& spent_outputs); +template void PrecomputedTransactionData::Init(const CTransaction& txTo, std::vector<CTxOut>&& spent_outputs, bool force); +template void PrecomputedTransactionData::Init(const CMutableTransaction& txTo, std::vector<CTxOut>&& spent_outputs, bool force); template PrecomputedTransactionData::PrecomputedTransactionData(const CTransaction& txTo); template PrecomputedTransactionData::PrecomputedTransactionData(const CMutableTransaction& txTo); static const CHashWriter HASHER_TAPSIGHASH = TaggedHash("TapSighash"); -static const CHashWriter HASHER_TAPLEAF = TaggedHash("TapLeaf"); -static const CHashWriter HASHER_TAPBRANCH = TaggedHash("TapBranch"); -static const CHashWriter HASHER_TAPTWEAK = TaggedHash("TapTweak"); +const CHashWriter HASHER_TAPLEAF = TaggedHash("TapLeaf"); +const CHashWriter HASHER_TAPBRANCH = TaggedHash("TapBranch"); + +static bool HandleMissingData(MissingDataBehavior mdb) +{ + switch (mdb) { + case MissingDataBehavior::ASSERT_FAIL: + assert(!"Missing data"); + break; + case MissingDataBehavior::FAIL: + return false; + } + assert(!"Unknown MissingDataBehavior value"); +} template<typename T> -bool SignatureHashSchnorr(uint256& hash_out, const ScriptExecutionData& execdata, const T& tx_to, uint32_t in_pos, uint8_t hash_type, SigVersion sigversion, const PrecomputedTransactionData& cache) +bool SignatureHashSchnorr(uint256& hash_out, const ScriptExecutionData& execdata, const T& tx_to, uint32_t in_pos, uint8_t hash_type, SigVersion sigversion, const PrecomputedTransactionData& cache, MissingDataBehavior mdb) { uint8_t ext_flag, key_version; switch (sigversion) { @@ -1509,7 +1520,9 @@ bool SignatureHashSchnorr(uint256& hash_out, const ScriptExecutionData& execdata assert(false); } assert(in_pos < tx_to.vin.size()); - assert(cache.m_bip341_taproot_ready && cache.m_spent_outputs_ready); + if (!(cache.m_bip341_taproot_ready && cache.m_spent_outputs_ready)) { + return HandleMissingData(mdb); + } CHashWriter ss = HASHER_TAPSIGHASH; @@ -1667,6 +1680,9 @@ bool GenericTransactionSignatureChecker<T>::CheckECDSASignature(const std::vecto int nHashType = vchSig.back(); vchSig.pop_back(); + // Witness sighashes need the amount. + if (sigversion == SigVersion::WITNESS_V0 && amount < 0) return HandleMissingData(m_mdb); + uint256 sighash = SignatureHash(scriptCode, *txTo, nIn, nHashType, amount, sigversion, this->txdata); if (!VerifyECDSASignature(vchSig, pubkey, sighash)) @@ -1695,8 +1711,8 @@ bool GenericTransactionSignatureChecker<T>::CheckSchnorrSignature(Span<const uns if (hashtype == SIGHASH_DEFAULT) return set_error(serror, SCRIPT_ERR_SCHNORR_SIG_HASHTYPE); } uint256 sighash; - assert(this->txdata); - if (!SignatureHashSchnorr(sighash, execdata, *txTo, nIn, hashtype, sigversion, *this->txdata)) { + if (!this->txdata) return HandleMissingData(m_mdb); + if (!SignatureHashSchnorr(sighash, execdata, *txTo, nIn, hashtype, sigversion, *this->txdata, m_mdb)) { return set_error(serror, SCRIPT_ERR_SCHNORR_SIG_HASHTYPE); } if (!VerifySchnorrSignature(sig, pubkey, sighash)) return set_error(serror, SCRIPT_ERR_SCHNORR_SIG); @@ -1834,7 +1850,7 @@ static bool ExecuteWitnessScript(const Span<const valtype>& stack_span, const CS static bool VerifyTaprootCommitment(const std::vector<unsigned char>& control, const std::vector<unsigned char>& program, const CScript& script, uint256& tapleaf_hash) { const int path_len = (control.size() - TAPROOT_CONTROL_BASE_SIZE) / TAPROOT_CONTROL_NODE_SIZE; - //! The inner pubkey (x-only, so no Y coordinate parity). + //! The internal pubkey (x-only, so no Y coordinate parity). const XOnlyPubKey p{uint256(std::vector<unsigned char>(control.begin() + 1, control.begin() + TAPROOT_CONTROL_BASE_SIZE))}; //! The output pubkey (taken from the scriptPubKey). const XOnlyPubKey q{uint256(program)}; @@ -1852,10 +1868,8 @@ static bool VerifyTaprootCommitment(const std::vector<unsigned char>& control, c } k = ss_branch.GetSHA256(); } - // Compute the tweak from the Merkle root and the inner pubkey. - k = (CHashWriter(HASHER_TAPTWEAK) << MakeSpan(p) << k).GetSHA256(); - // Verify that the output pubkey matches the tweaked inner pubkey, after correcting for parity. - return q.CheckPayToContract(p, k, control[0] & 1); + // Verify that the output pubkey matches the tweaked internal pubkey, after correcting for parity. + return q.CheckTapTweak(p, k, control[0] & 1); } static bool VerifyWitnessProgram(const CScriptWitness& witness, int witversion, const std::vector<unsigned char>& program, unsigned int flags, const BaseSignatureChecker& checker, ScriptError* serror, bool is_p2sh) @@ -1873,7 +1887,7 @@ static bool VerifyWitnessProgram(const CScriptWitness& witness, int witversion, const valtype& script_bytes = SpanPopBack(stack); exec_script = CScript(script_bytes.begin(), script_bytes.end()); uint256 hash_exec_script; - CSHA256().Write(&exec_script[0], exec_script.size()).Finalize(hash_exec_script.begin()); + CSHA256().Write(exec_script.data(), exec_script.size()).Finalize(hash_exec_script.begin()); if (memcmp(hash_exec_script.begin(), program.data(), 32)) { return set_error(serror, SCRIPT_ERR_WITNESS_PROGRAM_MISMATCH); } diff --git a/src/script/interpreter.h b/src/script/interpreter.h index b4c163c841..ced5c28bc1 100644 --- a/src/script/interpreter.h +++ b/src/script/interpreter.h @@ -6,6 +6,7 @@ #ifndef BITCOIN_SCRIPT_INTERPRETER_H #define BITCOIN_SCRIPT_INTERPRETER_H +#include <hash.h> #include <script/script_error.h> #include <span.h> #include <primitives/transaction.h> @@ -167,7 +168,7 @@ struct PrecomputedTransactionData PrecomputedTransactionData() = default; template <class T> - void Init(const T& tx, std::vector<CTxOut>&& spent_outputs); + void Init(const T& tx, std::vector<CTxOut>&& spent_outputs, bool force = false); template <class T> explicit PrecomputedTransactionData(const T& tx); @@ -218,6 +219,9 @@ static constexpr size_t TAPROOT_CONTROL_NODE_SIZE = 32; static constexpr size_t TAPROOT_CONTROL_MAX_NODE_COUNT = 128; static constexpr size_t TAPROOT_CONTROL_MAX_SIZE = TAPROOT_CONTROL_BASE_SIZE + TAPROOT_CONTROL_NODE_SIZE * TAPROOT_CONTROL_MAX_NODE_COUNT; +extern const CHashWriter HASHER_TAPLEAF; //!< Hasher with tag "TapLeaf" pre-fed to it. +extern const CHashWriter HASHER_TAPBRANCH; //!< Hasher with tag "TapBranch" pre-fed to it. + template <class T> uint256 SignatureHash(const CScript& scriptCode, const T& txTo, unsigned int nIn, int nHashType, const CAmount& amount, SigVersion sigversion, const PrecomputedTransactionData* cache = nullptr); @@ -247,11 +251,24 @@ public: virtual ~BaseSignatureChecker() {} }; +/** Enum to specify what *TransactionSignatureChecker's behavior should be + * when dealing with missing transaction data. + */ +enum class MissingDataBehavior +{ + ASSERT_FAIL, //!< Abort execution through assertion failure (for consensus code) + FAIL, //!< Just act as if the signature was invalid +}; + +template<typename T> +bool SignatureHashSchnorr(uint256& hash_out, const ScriptExecutionData& execdata, const T& tx_to, uint32_t in_pos, uint8_t hash_type, SigVersion sigversion, const PrecomputedTransactionData& cache, MissingDataBehavior mdb); + template <class T> class GenericTransactionSignatureChecker : public BaseSignatureChecker { private: const T* txTo; + const MissingDataBehavior m_mdb; unsigned int nIn; const CAmount amount; const PrecomputedTransactionData* txdata; @@ -261,8 +278,8 @@ protected: virtual bool VerifySchnorrSignature(Span<const unsigned char> sig, const XOnlyPubKey& pubkey, const uint256& sighash) const; public: - GenericTransactionSignatureChecker(const T* txToIn, unsigned int nInIn, const CAmount& amountIn) : txTo(txToIn), nIn(nInIn), amount(amountIn), txdata(nullptr) {} - GenericTransactionSignatureChecker(const T* txToIn, unsigned int nInIn, const CAmount& amountIn, const PrecomputedTransactionData& txdataIn) : txTo(txToIn), nIn(nInIn), amount(amountIn), txdata(&txdataIn) {} + GenericTransactionSignatureChecker(const T* txToIn, unsigned int nInIn, const CAmount& amountIn, MissingDataBehavior mdb) : txTo(txToIn), m_mdb(mdb), nIn(nInIn), amount(amountIn), txdata(nullptr) {} + GenericTransactionSignatureChecker(const T* txToIn, unsigned int nInIn, const CAmount& amountIn, const PrecomputedTransactionData& txdataIn, MissingDataBehavior mdb) : txTo(txToIn), m_mdb(mdb), nIn(nInIn), amount(amountIn), txdata(&txdataIn) {} bool CheckECDSASignature(const std::vector<unsigned char>& scriptSig, const std::vector<unsigned char>& vchPubKey, const CScript& scriptCode, SigVersion sigversion) const override; bool CheckSchnorrSignature(Span<const unsigned char> sig, Span<const unsigned char> pubkey, SigVersion sigversion, const ScriptExecutionData& execdata, ScriptError* serror = nullptr) const override; bool CheckLockTime(const CScriptNum& nLockTime) const override; @@ -272,12 +289,42 @@ public: using TransactionSignatureChecker = GenericTransactionSignatureChecker<CTransaction>; using MutableTransactionSignatureChecker = GenericTransactionSignatureChecker<CMutableTransaction>; +class DeferringSignatureChecker : public BaseSignatureChecker +{ +protected: + BaseSignatureChecker& m_checker; + +public: + DeferringSignatureChecker(BaseSignatureChecker& checker) : m_checker(checker) {} + + bool CheckECDSASignature(const std::vector<unsigned char>& scriptSig, const std::vector<unsigned char>& vchPubKey, const CScript& scriptCode, SigVersion sigversion) const override + { + return m_checker.CheckECDSASignature(scriptSig, vchPubKey, scriptCode, sigversion); + } + + bool CheckSchnorrSignature(Span<const unsigned char> sig, Span<const unsigned char> pubkey, SigVersion sigversion, const ScriptExecutionData& execdata, ScriptError* serror = nullptr) const override + { + return m_checker.CheckSchnorrSignature(sig, pubkey, sigversion, execdata, serror); + } + + bool CheckLockTime(const CScriptNum& nLockTime) const override + { + return m_checker.CheckLockTime(nLockTime); + } + bool CheckSequence(const CScriptNum& nSequence) const override + { + return m_checker.CheckSequence(nSequence); + } +}; + bool EvalScript(std::vector<std::vector<unsigned char> >& stack, const CScript& script, unsigned int flags, const BaseSignatureChecker& checker, SigVersion sigversion, ScriptExecutionData& execdata, ScriptError* error = nullptr); bool EvalScript(std::vector<std::vector<unsigned char> >& stack, const CScript& script, unsigned int flags, const BaseSignatureChecker& checker, SigVersion sigversion, ScriptError* error = nullptr); bool VerifyScript(const CScript& scriptSig, const CScript& scriptPubKey, const CScriptWitness* witness, unsigned int flags, const BaseSignatureChecker& checker, ScriptError* serror = nullptr); size_t CountWitnessSigOps(const CScript& scriptSig, const CScript& scriptPubKey, const CScriptWitness* witness, unsigned int flags); +bool CheckMinimalPush(const std::vector<unsigned char>& data, opcodetype opcode); + int FindAndDelete(CScript& script, const CScript& b); #endif // BITCOIN_SCRIPT_INTERPRETER_H diff --git a/src/script/sigcache.cpp b/src/script/sigcache.cpp index cf47d37e70..65867c1c14 100644 --- a/src/script/sigcache.cpp +++ b/src/script/sigcache.cpp @@ -12,8 +12,10 @@ #include <cuckoocache.h> -#include <boost/thread/lock_types.hpp> -#include <boost/thread/shared_mutex.hpp> +#include <algorithm> +#include <mutex> +#include <shared_mutex> +#include <vector> namespace { /** @@ -29,7 +31,7 @@ private: CSHA256 m_salted_hasher_schnorr; typedef CuckooCache::cache<uint256, SignatureCacheHasher> map_type; map_type setValid; - boost::shared_mutex cs_sigcache; + std::shared_mutex cs_sigcache; public: CSignatureCache() @@ -51,26 +53,26 @@ public: ComputeEntryECDSA(uint256& entry, const uint256 &hash, const std::vector<unsigned char>& vchSig, const CPubKey& pubkey) const { CSHA256 hasher = m_salted_hasher_ecdsa; - hasher.Write(hash.begin(), 32).Write(&pubkey[0], pubkey.size()).Write(&vchSig[0], vchSig.size()).Finalize(entry.begin()); + hasher.Write(hash.begin(), 32).Write(pubkey.data(), pubkey.size()).Write(vchSig.data(), vchSig.size()).Finalize(entry.begin()); } void ComputeEntrySchnorr(uint256& entry, const uint256 &hash, Span<const unsigned char> sig, const XOnlyPubKey& pubkey) const { CSHA256 hasher = m_salted_hasher_schnorr; - hasher.Write(hash.begin(), 32).Write(&pubkey[0], pubkey.size()).Write(sig.data(), sig.size()).Finalize(entry.begin()); + hasher.Write(hash.begin(), 32).Write(pubkey.data(), pubkey.size()).Write(sig.data(), sig.size()).Finalize(entry.begin()); } bool Get(const uint256& entry, const bool erase) { - boost::shared_lock<boost::shared_mutex> lock(cs_sigcache); + std::shared_lock<std::shared_mutex> lock(cs_sigcache); return setValid.contains(entry, erase); } void Set(const uint256& entry) { - boost::unique_lock<boost::shared_mutex> lock(cs_sigcache); + std::unique_lock<std::shared_mutex> lock(cs_sigcache); setValid.insert(entry); } uint32_t setup_bytes(size_t n) diff --git a/src/script/sigcache.h b/src/script/sigcache.h index bf0ba38c2d..7b6b91c963 100644 --- a/src/script/sigcache.h +++ b/src/script/sigcache.h @@ -27,7 +27,7 @@ private: bool store; public: - CachingTransactionSignatureChecker(const CTransaction* txToIn, unsigned int nInIn, const CAmount& amountIn, bool storeIn, PrecomputedTransactionData& txdataIn) : TransactionSignatureChecker(txToIn, nInIn, amountIn, txdataIn), store(storeIn) {} + CachingTransactionSignatureChecker(const CTransaction* txToIn, unsigned int nInIn, const CAmount& amountIn, bool storeIn, PrecomputedTransactionData& txdataIn) : TransactionSignatureChecker(txToIn, nInIn, amountIn, txdataIn, MissingDataBehavior::ASSERT_FAIL), store(storeIn) {} bool VerifyECDSASignature(const std::vector<unsigned char>& vchSig, const CPubKey& vchPubKey, const uint256& sighash) const override; bool VerifySchnorrSignature(Span<const unsigned char> sig, const XOnlyPubKey& pubkey, const uint256& sighash) const override; diff --git a/src/script/sign.cpp b/src/script/sign.cpp index 8afbe9ebed..65276f641f 100644 --- a/src/script/sign.cpp +++ b/src/script/sign.cpp @@ -11,13 +11,28 @@ #include <script/signingprovider.h> #include <script/standard.h> #include <uint256.h> +#include <util/vector.h> typedef std::vector<unsigned char> valtype; -MutableTransactionSignatureCreator::MutableTransactionSignatureCreator(const CMutableTransaction* txToIn, unsigned int nInIn, const CAmount& amountIn, int nHashTypeIn) : txTo(txToIn), nIn(nInIn), nHashType(nHashTypeIn), amount(amountIn), checker(txTo, nIn, amountIn) {} +MutableTransactionSignatureCreator::MutableTransactionSignatureCreator(const CMutableTransaction* txToIn, unsigned int nInIn, const CAmount& amountIn, int nHashTypeIn) + : txTo(txToIn), nIn(nInIn), nHashType(nHashTypeIn), amount(amountIn), checker(txTo, nIn, amountIn, MissingDataBehavior::FAIL), + m_txdata(nullptr) +{ +} + +MutableTransactionSignatureCreator::MutableTransactionSignatureCreator(const CMutableTransaction* txToIn, unsigned int nInIn, const CAmount& amountIn, const PrecomputedTransactionData* txdata, int nHashTypeIn) + : txTo(txToIn), nIn(nInIn), nHashType(nHashTypeIn), amount(amountIn), + checker(txdata ? MutableTransactionSignatureChecker(txTo, nIn, amount, *txdata, MissingDataBehavior::FAIL) : + MutableTransactionSignatureChecker(txTo, nIn, amount, MissingDataBehavior::FAIL)), + m_txdata(txdata) +{ +} bool MutableTransactionSignatureCreator::CreateSig(const SigningProvider& provider, std::vector<unsigned char>& vchSig, const CKeyID& address, const CScript& scriptCode, SigVersion sigversion) const { + assert(sigversion == SigVersion::BASE || sigversion == SigVersion::WITNESS_V0); + CKey key; if (!provider.GetKey(address, key)) return false; @@ -26,10 +41,61 @@ bool MutableTransactionSignatureCreator::CreateSig(const SigningProvider& provid if (sigversion == SigVersion::WITNESS_V0 && !key.IsCompressed()) return false; - uint256 hash = SignatureHash(scriptCode, *txTo, nIn, nHashType, amount, sigversion); + // Signing without known amount does not work in witness scripts. + if (sigversion == SigVersion::WITNESS_V0 && !MoneyRange(amount)) return false; + + // BASE/WITNESS_V0 signatures don't support explicit SIGHASH_DEFAULT, use SIGHASH_ALL instead. + const int hashtype = nHashType == SIGHASH_DEFAULT ? SIGHASH_ALL : nHashType; + + uint256 hash = SignatureHash(scriptCode, *txTo, nIn, hashtype, amount, sigversion, m_txdata); if (!key.Sign(hash, vchSig)) return false; - vchSig.push_back((unsigned char)nHashType); + vchSig.push_back((unsigned char)hashtype); + return true; +} + +bool MutableTransactionSignatureCreator::CreateSchnorrSig(const SigningProvider& provider, std::vector<unsigned char>& sig, const XOnlyPubKey& pubkey, const uint256* leaf_hash, const uint256* merkle_root, SigVersion sigversion) const +{ + assert(sigversion == SigVersion::TAPROOT || sigversion == SigVersion::TAPSCRIPT); + + CKey key; + { + // For now, use the old full pubkey-based key derivation logic. As it indexed by + // Hash160(full pubkey), we need to try both a version prefixed with 0x02, and one + // with 0x03. + unsigned char b[33] = {0x02}; + std::copy(pubkey.begin(), pubkey.end(), b + 1); + CPubKey fullpubkey; + fullpubkey.Set(b, b + 33); + CKeyID keyid = fullpubkey.GetID(); + if (!provider.GetKey(keyid, key)) { + b[0] = 0x03; + fullpubkey.Set(b, b + 33); + CKeyID keyid = fullpubkey.GetID(); + if (!provider.GetKey(keyid, key)) return false; + } + } + + // BIP341/BIP342 signing needs lots of precomputed transaction data. While some + // (non-SIGHASH_DEFAULT) sighash modes exist that can work with just some subset + // of data present, for now, only support signing when everything is provided. + if (!m_txdata || !m_txdata->m_bip341_taproot_ready || !m_txdata->m_spent_outputs_ready) return false; + + ScriptExecutionData execdata; + execdata.m_annex_init = true; + execdata.m_annex_present = false; // Only support annex-less signing for now. + if (sigversion == SigVersion::TAPSCRIPT) { + execdata.m_codeseparator_pos_init = true; + execdata.m_codeseparator_pos = 0xFFFFFFFF; // Only support non-OP_CODESEPARATOR BIP342 signing for now. + if (!leaf_hash) return false; // BIP342 signing needs leaf hash. + execdata.m_tapleaf_hash_init = true; + execdata.m_tapleaf_hash = *leaf_hash; + } + uint256 hash; + if (!SignatureHashSchnorr(hash, execdata, *txTo, nIn, nHashType, sigversion, *m_txdata, MissingDataBehavior::FAIL)) return false; + sig.resize(64); + if (!key.SignSchnorr(hash, sig, merkle_root, nullptr)) return false; + if (nHashType) sig.push_back(nHashType); return true; } @@ -89,6 +155,86 @@ static bool CreateSig(const BaseSignatureCreator& creator, SignatureData& sigdat return false; } +static bool CreateTaprootScriptSig(const BaseSignatureCreator& creator, SignatureData& sigdata, const SigningProvider& provider, std::vector<unsigned char>& sig_out, const XOnlyPubKey& pubkey, const uint256& leaf_hash, SigVersion sigversion) +{ + auto lookup_key = std::make_pair(pubkey, leaf_hash); + auto it = sigdata.taproot_script_sigs.find(lookup_key); + if (it != sigdata.taproot_script_sigs.end()) { + sig_out = it->second; + } + if (creator.CreateSchnorrSig(provider, sig_out, pubkey, &leaf_hash, nullptr, sigversion)) { + sigdata.taproot_script_sigs[lookup_key] = sig_out; + return true; + } + return false; +} + +static bool SignTaprootScript(const SigningProvider& provider, const BaseSignatureCreator& creator, SignatureData& sigdata, int leaf_version, const CScript& script, std::vector<valtype>& result) +{ + // Only BIP342 tapscript signing is supported for now. + if (leaf_version != TAPROOT_LEAF_TAPSCRIPT) return false; + SigVersion sigversion = SigVersion::TAPSCRIPT; + + uint256 leaf_hash = (CHashWriter(HASHER_TAPLEAF) << uint8_t(leaf_version) << script).GetSHA256(); + + // <xonly pubkey> OP_CHECKSIG + if (script.size() == 34 && script[33] == OP_CHECKSIG && script[0] == 0x20) { + XOnlyPubKey pubkey(MakeSpan(script).subspan(1, 32)); + std::vector<unsigned char> sig; + if (CreateTaprootScriptSig(creator, sigdata, provider, sig, pubkey, leaf_hash, sigversion)) { + result = Vector(std::move(sig)); + return true; + } + } + + return false; +} + +static bool SignTaproot(const SigningProvider& provider, const BaseSignatureCreator& creator, const WitnessV1Taproot& output, SignatureData& sigdata, std::vector<valtype>& result) +{ + TaprootSpendData spenddata; + + // Gather information about this output. + if (provider.GetTaprootSpendData(output, spenddata)) { + sigdata.tr_spenddata.Merge(spenddata); + } + + // Try key path spending. + { + std::vector<unsigned char> sig; + if (sigdata.taproot_key_path_sig.size() == 0) { + if (creator.CreateSchnorrSig(provider, sig, spenddata.internal_key, nullptr, &spenddata.merkle_root, SigVersion::TAPROOT)) { + sigdata.taproot_key_path_sig = sig; + } + } + if (sigdata.taproot_key_path_sig.size()) { + result = Vector(sigdata.taproot_key_path_sig); + return true; + } + } + + // Try script path spending. + std::vector<std::vector<unsigned char>> smallest_result_stack; + for (const auto& [key, control_blocks] : sigdata.tr_spenddata.scripts) { + const auto& [script, leaf_ver] = key; + std::vector<std::vector<unsigned char>> result_stack; + if (SignTaprootScript(provider, creator, sigdata, leaf_ver, script, result_stack)) { + result_stack.emplace_back(std::begin(script), std::end(script)); // Push the script + result_stack.push_back(*control_blocks.begin()); // Push the smallest control block + if (smallest_result_stack.size() == 0 || + GetSerializeSize(result_stack, PROTOCOL_VERSION) < GetSerializeSize(smallest_result_stack, PROTOCOL_VERSION)) { + smallest_result_stack = std::move(result_stack); + } + } + } + if (smallest_result_stack.size() != 0) { + result = std::move(smallest_result_stack); + return true; + } + + return false; +} + /** * Sign scriptPubKey using signature made with creator. * Signatures are returned in scriptSigRet (or returns false if scriptPubKey can't be signed), @@ -106,12 +252,10 @@ static bool SignStep(const SigningProvider& provider, const BaseSignatureCreator std::vector<valtype> vSolutions; whichTypeRet = Solver(scriptPubKey, vSolutions); - switch (whichTypeRet) - { + switch (whichTypeRet) { case TxoutType::NONSTANDARD: case TxoutType::NULL_DATA: case TxoutType::WITNESS_UNKNOWN: - case TxoutType::WITNESS_V1_TAPROOT: return false; case TxoutType::PUBKEY: if (!CreateSig(creator, sigdata, provider, sig, CPubKey(vSolutions[0]), scriptPubKey, sigversion)) return false; @@ -165,7 +309,7 @@ static bool SignStep(const SigningProvider& provider, const BaseSignatureCreator return true; case TxoutType::WITNESS_V0_SCRIPTHASH: - CRIPEMD160().Write(&vSolutions[0][0], vSolutions[0].size()).Finalize(h160.begin()); + CRIPEMD160().Write(vSolutions[0].data(), vSolutions[0].size()).Finalize(h160.begin()); if (GetCScript(provider, sigdata, CScriptID{h160}, scriptRet)) { ret.push_back(std::vector<unsigned char>(scriptRet.begin(), scriptRet.end())); return true; @@ -174,9 +318,10 @@ static bool SignStep(const SigningProvider& provider, const BaseSignatureCreator sigdata.missing_witness_script = uint256(vSolutions[0]); return false; - default: - return false; - } + case TxoutType::WITNESS_V1_TAPROOT: + return SignTaproot(provider, creator, WitnessV1Taproot(XOnlyPubKey{vSolutions[0]}), sigdata, ret); + } // no default case, so the compiler can warn about missing cases + assert(false); } static CScript PushAll(const std::vector<valtype>& values) @@ -205,7 +350,6 @@ bool ProduceSignature(const SigningProvider& provider, const BaseSignatureCreato bool solved = SignStep(provider, creator, fromPubKey, result, whichType, SigVersion::BASE, sigdata); bool P2SH = false; CScript subscript; - sigdata.scriptWitness.stack.clear(); if (solved && whichType == TxoutType::SCRIPTHASH) { @@ -238,10 +382,17 @@ bool ProduceSignature(const SigningProvider& provider, const BaseSignatureCreato sigdata.scriptWitness.stack = result; sigdata.witness = true; result.clear(); + } else if (whichType == TxoutType::WITNESS_V1_TAPROOT && !P2SH) { + sigdata.witness = true; + if (solved) { + sigdata.scriptWitness.stack = std::move(result); + } + result.clear(); } else if (solved && whichType == TxoutType::WITNESS_UNKNOWN) { sigdata.witness = true; } + if (!sigdata.witness) sigdata.scriptWitness.stack.clear(); if (P2SH) { result.push_back(std::vector<unsigned char>(subscript.begin(), subscript.end())); } @@ -253,17 +404,17 @@ bool ProduceSignature(const SigningProvider& provider, const BaseSignatureCreato } namespace { -class SignatureExtractorChecker final : public BaseSignatureChecker +class SignatureExtractorChecker final : public DeferringSignatureChecker { private: SignatureData& sigdata; - BaseSignatureChecker& checker; public: - SignatureExtractorChecker(SignatureData& sigdata, BaseSignatureChecker& checker) : sigdata(sigdata), checker(checker) {} + SignatureExtractorChecker(SignatureData& sigdata, BaseSignatureChecker& checker) : DeferringSignatureChecker(checker), sigdata(sigdata) {} + bool CheckECDSASignature(const std::vector<unsigned char>& scriptSig, const std::vector<unsigned char>& vchPubKey, const CScript& scriptCode, SigVersion sigversion) const override { - if (checker.CheckECDSASignature(scriptSig, vchPubKey, scriptCode, sigversion)) { + if (m_checker.CheckECDSASignature(scriptSig, vchPubKey, scriptCode, sigversion)) { CPubKey pubkey(vchPubKey); sigdata.signatures.emplace(pubkey.GetID(), SigPair(pubkey, scriptSig)); return true; @@ -295,7 +446,7 @@ SignatureData DataFromTransaction(const CMutableTransaction& tx, unsigned int nI Stacks stack(data); // Get signatures - MutableTransactionSignatureChecker tx_checker(&tx, nIn, txout.nValue); + MutableTransactionSignatureChecker tx_checker(&tx, nIn, txout.nValue, MissingDataBehavior::FAIL); SignatureExtractorChecker extractor_checker(data, tx_checker); if (VerifyScript(data.scriptSig, txout.scriptPubKey, &data.scriptWitness, STANDARD_SCRIPT_VERIFY_FLAGS, extractor_checker)) { data.complete = true; @@ -402,6 +553,7 @@ class DummySignatureChecker final : public BaseSignatureChecker public: DummySignatureChecker() {} bool CheckECDSASignature(const std::vector<unsigned char>& scriptSig, const std::vector<unsigned char>& vchPubKey, const CScript& scriptCode, SigVersion sigversion) const override { return true; } + bool CheckSchnorrSignature(Span<const unsigned char> sig, Span<const unsigned char> pubkey, SigVersion sigversion, const ScriptExecutionData& execdata, ScriptError* serror) const override { return true; } }; const DummySignatureChecker DUMMY_CHECKER; @@ -427,6 +579,11 @@ public: vchSig[6 + m_r_len + m_s_len] = SIGHASH_ALL; return true; } + bool CreateSchnorrSig(const SigningProvider& provider, std::vector<unsigned char>& sig, const XOnlyPubKey& pubkey, const uint256* leaf_hash, const uint256* tweak, SigVersion sigversion) const override + { + sig.assign(64, '\000'); + return true; + } }; } @@ -476,6 +633,26 @@ bool SignTransaction(CMutableTransaction& mtx, const SigningProvider* keystore, // Use CTransaction for the constant parts of the // transaction to avoid rehashing. const CTransaction txConst(mtx); + + PrecomputedTransactionData txdata; + std::vector<CTxOut> spent_outputs; + spent_outputs.resize(mtx.vin.size()); + bool have_all_spent_outputs = true; + for (unsigned int i = 0; i < mtx.vin.size(); i++) { + CTxIn& txin = mtx.vin[i]; + auto coin = coins.find(txin.prevout); + if (coin == coins.end() || coin->second.IsSpent()) { + have_all_spent_outputs = false; + } else { + spent_outputs[i] = CTxOut(coin->second.out.nValue, coin->second.out.scriptPubKey); + } + } + if (have_all_spent_outputs) { + txdata.Init(txConst, std::move(spent_outputs), true); + } else { + txdata.Init(txConst, {}, true); + } + // Sign what we can: for (unsigned int i = 0; i < mtx.vin.size(); i++) { CTxIn& txin = mtx.vin[i]; @@ -490,7 +667,7 @@ bool SignTransaction(CMutableTransaction& mtx, const SigningProvider* keystore, SignatureData sigdata = DataFromTransaction(mtx, i, coin->second.out); // Only sign SIGHASH_SINGLE if there's a corresponding output: if (!fHashSingle || (i < mtx.vout.size())) { - ProduceSignature(*keystore, MutableTransactionSignatureCreator(&mtx, i, amount, nHashType), prevPubKey, sigdata); + ProduceSignature(*keystore, MutableTransactionSignatureCreator(&mtx, i, amount, &txdata, nHashType), prevPubKey, sigdata); } UpdateInput(txin, sigdata); @@ -502,7 +679,7 @@ bool SignTransaction(CMutableTransaction& mtx, const SigningProvider* keystore, } ScriptError serror = SCRIPT_ERR_OK; - if (!VerifyScript(txin.scriptSig, prevPubKey, &txin.scriptWitness, STANDARD_SCRIPT_VERIFY_FLAGS, TransactionSignatureChecker(&txConst, i, amount), &serror)) { + if (!VerifyScript(txin.scriptSig, prevPubKey, &txin.scriptWitness, STANDARD_SCRIPT_VERIFY_FLAGS, TransactionSignatureChecker(&txConst, i, amount, txdata, MissingDataBehavior::FAIL), &serror)) { if (serror == SCRIPT_ERR_INVALID_STACK_OPERATION) { // Unable to sign input and verification failed (possible attempt to partially sign). input_errors[i] = "Unable to sign input, invalid stack size (possibly missing key)"; diff --git a/src/script/sign.h b/src/script/sign.h index a1cfe1574d..b4e7318892 100644 --- a/src/script/sign.h +++ b/src/script/sign.h @@ -11,13 +11,13 @@ #include <pubkey.h> #include <script/interpreter.h> #include <script/keyorigin.h> +#include <script/standard.h> #include <span.h> #include <streams.h> class CKey; class CKeyID; class CScript; -class CScriptID; class CTransaction; class SigningProvider; @@ -31,6 +31,7 @@ public: /** 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; + virtual bool CreateSchnorrSig(const SigningProvider& provider, std::vector<unsigned char>& sig, const XOnlyPubKey& pubkey, const uint256* leaf_hash, const uint256* merkle_root, SigVersion sigversion) const =0; }; /** A signature creator for transactions. */ @@ -40,11 +41,14 @@ class MutableTransactionSignatureCreator : public BaseSignatureCreator { int nHashType; CAmount amount; const MutableTransactionSignatureChecker checker; + const PrecomputedTransactionData* m_txdata; public: MutableTransactionSignatureCreator(const CMutableTransaction* txToIn, unsigned int nInIn, const CAmount& amountIn, int nHashTypeIn = SIGHASH_ALL); + MutableTransactionSignatureCreator(const CMutableTransaction* txToIn, unsigned int nInIn, const CAmount& amountIn, const PrecomputedTransactionData* txdata, 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; + bool CreateSchnorrSig(const SigningProvider& provider, std::vector<unsigned char>& sig, const XOnlyPubKey& pubkey, const uint256* leaf_hash, const uint256* merkle_root, SigVersion sigversion) const override; }; /** A signature creator that just produces 71-byte empty signatures. */ @@ -64,8 +68,11 @@ struct SignatureData { 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. + TaprootSpendData tr_spenddata; ///< Taproot spending data. 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. std::map<CKeyID, std::pair<CPubKey, KeyOriginInfo>> misc_pubkeys; + std::vector<unsigned char> taproot_key_path_sig; /// Schnorr signature for key path spending + std::map<std::pair<XOnlyPubKey, uint256>, std::vector<unsigned char>> taproot_script_sigs; ///< (Partial) schnorr signatures, indexed by XOnlyPubKey and leaf_hash. std::vector<CKeyID> missing_pubkeys; ///< KeyIDs of pubkeys which could not be found std::vector<CKeyID> missing_sigs; ///< KeyIDs of pubkeys for signatures which could not be found uint160 missing_redeem_script; ///< ScriptID of the missing redeemScript (if any) diff --git a/src/script/signingprovider.cpp b/src/script/signingprovider.cpp index 9781ec32af..b80fbe22ce 100644 --- a/src/script/signingprovider.cpp +++ b/src/script/signingprovider.cpp @@ -44,6 +44,11 @@ bool HidingSigningProvider::GetKeyOrigin(const CKeyID& keyid, KeyOriginInfo& inf return m_provider->GetKeyOrigin(keyid, info); } +bool HidingSigningProvider::GetTaprootSpendData(const XOnlyPubKey& output_key, TaprootSpendData& spenddata) const +{ + return m_provider->GetTaprootSpendData(output_key, spenddata); +} + bool FlatSigningProvider::GetCScript(const CScriptID& scriptid, CScript& script) const { return LookupHelper(scripts, scriptid, script); } bool FlatSigningProvider::GetPubKey(const CKeyID& keyid, CPubKey& pubkey) const { return LookupHelper(pubkeys, keyid, pubkey); } bool FlatSigningProvider::GetKeyOrigin(const CKeyID& keyid, KeyOriginInfo& info) const @@ -54,6 +59,10 @@ bool FlatSigningProvider::GetKeyOrigin(const CKeyID& keyid, KeyOriginInfo& info) return ret; } bool FlatSigningProvider::GetKey(const CKeyID& keyid, CKey& key) const { return LookupHelper(keys, keyid, key); } +bool FlatSigningProvider::GetTaprootSpendData(const XOnlyPubKey& output_key, TaprootSpendData& spenddata) const +{ + return LookupHelper(tr_spenddata, output_key, spenddata); +} FlatSigningProvider Merge(const FlatSigningProvider& a, const FlatSigningProvider& b) { @@ -66,6 +75,10 @@ FlatSigningProvider Merge(const FlatSigningProvider& a, const FlatSigningProvide ret.keys.insert(b.keys.begin(), b.keys.end()); ret.origins = a.origins; ret.origins.insert(b.origins.begin(), b.origins.end()); + ret.tr_spenddata = a.tr_spenddata; + for (const auto& [output_key, spenddata] : b.tr_spenddata) { + ret.tr_spenddata[output_key].Merge(spenddata); + } return ret; } diff --git a/src/script/signingprovider.h b/src/script/signingprovider.h index 76f31d2f6f..939ae10622 100644 --- a/src/script/signingprovider.h +++ b/src/script/signingprovider.h @@ -25,6 +25,7 @@ public: virtual bool GetKey(const CKeyID &address, CKey& key) const { return false; } virtual bool HaveKey(const CKeyID &address) const { return false; } virtual bool GetKeyOrigin(const CKeyID& keyid, KeyOriginInfo& info) const { return false; } + virtual bool GetTaprootSpendData(const XOnlyPubKey& output_key, TaprootSpendData& spenddata) const { return false; } }; extern const SigningProvider& DUMMY_SIGNING_PROVIDER; @@ -42,6 +43,7 @@ public: bool GetPubKey(const CKeyID& keyid, CPubKey& pubkey) const override; bool GetKey(const CKeyID& keyid, CKey& key) const override; bool GetKeyOrigin(const CKeyID& keyid, KeyOriginInfo& info) const override; + bool GetTaprootSpendData(const XOnlyPubKey& output_key, TaprootSpendData& spenddata) const override; }; struct FlatSigningProvider final : public SigningProvider @@ -50,11 +52,13 @@ struct FlatSigningProvider final : public SigningProvider std::map<CKeyID, CPubKey> pubkeys; std::map<CKeyID, std::pair<CPubKey, KeyOriginInfo>> origins; std::map<CKeyID, CKey> keys; + std::map<XOnlyPubKey, TaprootSpendData> tr_spenddata; /** Map from output key to spend data. */ bool GetCScript(const CScriptID& scriptid, CScript& script) const override; bool GetPubKey(const CKeyID& keyid, CPubKey& pubkey) const override; bool GetKeyOrigin(const CKeyID& keyid, KeyOriginInfo& info) const override; bool GetKey(const CKeyID& keyid, CKey& key) const override; + bool GetTaprootSpendData(const XOnlyPubKey& output_key, TaprootSpendData& spenddata) const override; }; FlatSigningProvider Merge(const FlatSigningProvider& a, const FlatSigningProvider& b); diff --git a/src/script/standard.cpp b/src/script/standard.cpp index 7967c01858..748f00dda5 100644 --- a/src/script/standard.cpp +++ b/src/script/standard.cpp @@ -6,8 +6,11 @@ #include <script/standard.h> #include <crypto/sha256.h> +#include <hash.h> #include <pubkey.h> +#include <script/interpreter.h> #include <script/script.h> +#include <util/strencodings.h> #include <string> @@ -45,8 +48,7 @@ WitnessV0ScriptHash::WitnessV0ScriptHash(const CScript& in) std::string GetTxnOutputType(TxoutType t) { - switch (t) - { + switch (t) { case TxoutType::NONSTANDARD: return "nonstandard"; case TxoutType::PUBKEY: return "pubkey"; case TxoutType::PUBKEYHASH: return "pubkeyhash"; @@ -89,21 +91,53 @@ static constexpr bool IsSmallInteger(opcodetype opcode) return opcode >= OP_1 && opcode <= OP_16; } -static bool MatchMultisig(const CScript& script, unsigned int& required, std::vector<valtype>& pubkeys) +static constexpr bool IsPushdataOp(opcodetype opcode) +{ + return opcode > OP_FALSE && opcode <= OP_PUSHDATA4; +} + +static constexpr bool IsValidMultisigKeyCount(int n_keys) +{ + return n_keys > 0 && n_keys <= MAX_PUBKEYS_PER_MULTISIG; +} + +static bool GetMultisigKeyCount(opcodetype opcode, valtype data, int& count) +{ + if (IsSmallInteger(opcode)) { + count = CScript::DecodeOP_N(opcode); + return IsValidMultisigKeyCount(count); + } + + if (IsPushdataOp(opcode)) { + if (!CheckMinimalPush(data, opcode)) return false; + try { + count = CScriptNum(data, /* fRequireMinimal = */ true).getint(); + return IsValidMultisigKeyCount(count); + } catch (const scriptnum_error&) { + return false; + } + } + + return false; +} + +static bool MatchMultisig(const CScript& script, int& required_sigs, std::vector<valtype>& pubkeys) { opcodetype opcode; valtype data; + int num_keys; + CScript::const_iterator it = script.begin(); if (script.size() < 1 || script.back() != OP_CHECKMULTISIG) return false; - if (!script.GetOp(it, opcode, data) || !IsSmallInteger(opcode)) return false; - required = CScript::DecodeOP_N(opcode); + if (!script.GetOp(it, opcode, data) || !GetMultisigKeyCount(opcode, data, required_sigs)) return false; while (script.GetOp(it, opcode, data) && CPubKey::ValidSize(data)) { pubkeys.emplace_back(std::move(data)); } - if (!IsSmallInteger(opcode)) return false; - unsigned int keys = CScript::DecodeOP_N(opcode); - if (pubkeys.size() != keys || keys < required) return false; + if (!GetMultisigKeyCount(opcode, data, num_keys)) return false; + + if (pubkeys.size() != static_cast<unsigned long>(num_keys) || num_keys < required_sigs) return false; + return (it + 1 == script.end()); } @@ -124,15 +158,14 @@ TxoutType Solver(const CScript& scriptPubKey, std::vector<std::vector<unsigned c std::vector<unsigned char> witnessprogram; if (scriptPubKey.IsWitnessProgram(witnessversion, witnessprogram)) { if (witnessversion == 0 && witnessprogram.size() == WITNESS_V0_KEYHASH_SIZE) { - vSolutionsRet.push_back(witnessprogram); + vSolutionsRet.push_back(std::move(witnessprogram)); return TxoutType::WITNESS_V0_KEYHASH; } if (witnessversion == 0 && witnessprogram.size() == WITNESS_V0_SCRIPTHASH_SIZE) { - vSolutionsRet.push_back(witnessprogram); + vSolutionsRet.push_back(std::move(witnessprogram)); return TxoutType::WITNESS_V0_SCRIPTHASH; } if (witnessversion == 1 && witnessprogram.size() == WITNESS_V1_TAPROOT_SIZE) { - vSolutionsRet.push_back(std::vector<unsigned char>{(unsigned char)witnessversion}); vSolutionsRet.push_back(std::move(witnessprogram)); return TxoutType::WITNESS_V1_TAPROOT; } @@ -164,12 +197,12 @@ TxoutType Solver(const CScript& scriptPubKey, std::vector<std::vector<unsigned c return TxoutType::PUBKEYHASH; } - unsigned int required; + int required; std::vector<std::vector<unsigned char>> keys; if (MatchMultisig(scriptPubKey, required, keys)) { - vSolutionsRet.push_back({static_cast<unsigned char>(required)}); // safe as required is in range 1..16 + vSolutionsRet.push_back({static_cast<unsigned char>(required)}); // safe as required is in range 1..20 vSolutionsRet.insert(vSolutionsRet.end(), keys.begin(), keys.end()); - vSolutionsRet.push_back({static_cast<unsigned char>(keys.size())}); // safe as size is in range 1..16 + vSolutionsRet.push_back({static_cast<unsigned char>(keys.size())}); // safe as size is in range 1..20 return TxoutType::MULTISIG; } @@ -182,7 +215,8 @@ bool ExtractDestination(const CScript& scriptPubKey, CTxDestination& addressRet) std::vector<valtype> vSolutions; TxoutType whichType = Solver(scriptPubKey, vSolutions); - if (whichType == TxoutType::PUBKEY) { + switch (whichType) { + case TxoutType::PUBKEY: { CPubKey pubKey(vSolutions[0]); if (!pubKey.IsValid()) return false; @@ -190,26 +224,33 @@ bool ExtractDestination(const CScript& scriptPubKey, CTxDestination& addressRet) addressRet = PKHash(pubKey); return true; } - else if (whichType == TxoutType::PUBKEYHASH) - { + case TxoutType::PUBKEYHASH: { addressRet = PKHash(uint160(vSolutions[0])); return true; } - else if (whichType == TxoutType::SCRIPTHASH) - { + case TxoutType::SCRIPTHASH: { addressRet = ScriptHash(uint160(vSolutions[0])); return true; - } else if (whichType == TxoutType::WITNESS_V0_KEYHASH) { + } + case TxoutType::WITNESS_V0_KEYHASH: { WitnessV0KeyHash hash; std::copy(vSolutions[0].begin(), vSolutions[0].end(), hash.begin()); addressRet = hash; return true; - } else if (whichType == TxoutType::WITNESS_V0_SCRIPTHASH) { + } + case TxoutType::WITNESS_V0_SCRIPTHASH: { WitnessV0ScriptHash hash; std::copy(vSolutions[0].begin(), vSolutions[0].end(), hash.begin()); addressRet = hash; return true; - } else if (whichType == TxoutType::WITNESS_UNKNOWN || whichType == TxoutType::WITNESS_V1_TAPROOT) { + } + case TxoutType::WITNESS_V1_TAPROOT: { + WitnessV1Taproot tap; + std::copy(vSolutions[0].begin(), vSolutions[0].end(), tap.begin()); + addressRet = tap; + return true; + } + case TxoutType::WITNESS_UNKNOWN: { WitnessUnknown unk; unk.version = vSolutions[0][0]; std::copy(vSolutions[1].begin(), vSolutions[1].end(), unk.program); @@ -217,10 +258,15 @@ bool ExtractDestination(const CScript& scriptPubKey, CTxDestination& addressRet) addressRet = unk; return true; } - // Multisig txns have more than one address... - return false; + case TxoutType::MULTISIG: + case TxoutType::NULL_DATA: + case TxoutType::NONSTANDARD: + return false; + } // no default case, so the compiler can warn about missing cases + assert(false); } +// TODO: from v23 ("addresses" and "reqSigs" deprecated) "ExtractDestinations" should be removed bool ExtractDestinations(const CScript& scriptPubKey, TxoutType& typeRet, std::vector<CTxDestination>& addressRet, int& nRequiredRet) { addressRet.clear(); @@ -290,6 +336,11 @@ public: return CScript() << OP_0 << ToByteVector(id); } + CScript operator()(const WitnessV1Taproot& tap) const + { + return CScript() << OP_1 << ToByteVector(tap); + } + CScript operator()(const WitnessUnknown& id) const { return CScript() << CScript::EncodeOP_N(id.version) << std::vector<unsigned char>(id.program, id.program + id.length); @@ -311,13 +362,161 @@ CScript GetScriptForMultisig(int nRequired, const std::vector<CPubKey>& keys) { CScript script; - script << CScript::EncodeOP_N(nRequired); + script << nRequired; for (const CPubKey& key : keys) script << ToByteVector(key); - script << CScript::EncodeOP_N(keys.size()) << OP_CHECKMULTISIG; + script << keys.size() << OP_CHECKMULTISIG; + return script; } bool IsValidDestination(const CTxDestination& dest) { return dest.index() != 0; } + +/*static*/ TaprootBuilder::NodeInfo TaprootBuilder::Combine(NodeInfo&& a, NodeInfo&& b) +{ + NodeInfo ret; + /* Iterate over all tracked leaves in a, add b's hash to their Merkle branch, and move them to ret. */ + for (auto& leaf : a.leaves) { + leaf.merkle_branch.push_back(b.hash); + ret.leaves.emplace_back(std::move(leaf)); + } + /* Iterate over all tracked leaves in b, add a's hash to their Merkle branch, and move them to ret. */ + for (auto& leaf : b.leaves) { + leaf.merkle_branch.push_back(a.hash); + ret.leaves.emplace_back(std::move(leaf)); + } + /* Lexicographically sort a and b's hash, and compute parent hash. */ + if (a.hash < b.hash) { + ret.hash = (CHashWriter(HASHER_TAPBRANCH) << a.hash << b.hash).GetSHA256(); + } else { + ret.hash = (CHashWriter(HASHER_TAPBRANCH) << b.hash << a.hash).GetSHA256(); + } + return ret; +} + +void TaprootSpendData::Merge(TaprootSpendData other) +{ + // TODO: figure out how to better deal with conflicting information + // being merged. + if (internal_key.IsNull() && !other.internal_key.IsNull()) { + internal_key = other.internal_key; + } + if (merkle_root.IsNull() && !other.merkle_root.IsNull()) { + merkle_root = other.merkle_root; + } + for (auto& [key, control_blocks] : other.scripts) { + scripts[key].merge(std::move(control_blocks)); + } +} + +void TaprootBuilder::Insert(TaprootBuilder::NodeInfo&& node, int depth) +{ + assert(depth >= 0 && (size_t)depth <= TAPROOT_CONTROL_MAX_NODE_COUNT); + /* We cannot insert a leaf at a lower depth while a deeper branch is unfinished. Doing + * so would mean the Add() invocations do not correspond to a DFS traversal of a + * binary tree. */ + if ((size_t)depth + 1 < m_branch.size()) { + m_valid = false; + return; + } + /* As long as an entry in the branch exists at the specified depth, combine it and propagate up. + * The 'node' variable is overwritten here with the newly combined node. */ + while (m_valid && m_branch.size() > (size_t)depth && m_branch[depth].has_value()) { + node = Combine(std::move(node), std::move(*m_branch[depth])); + m_branch.pop_back(); + if (depth == 0) m_valid = false; /* Can't propagate further up than the root */ + --depth; + } + if (m_valid) { + /* Make sure the branch is big enough to place the new node. */ + if (m_branch.size() <= (size_t)depth) m_branch.resize((size_t)depth + 1); + assert(!m_branch[depth].has_value()); + m_branch[depth] = std::move(node); + } +} + +/*static*/ bool TaprootBuilder::ValidDepths(const std::vector<int>& depths) +{ + std::vector<bool> branch; + for (int depth : depths) { + // This inner loop corresponds to effectively the same logic on branch + // as what Insert() performs on the m_branch variable. Instead of + // storing a NodeInfo object, just remember whether or not there is one + // at that depth. + if (depth < 0 || (size_t)depth > TAPROOT_CONTROL_MAX_NODE_COUNT) return false; + if ((size_t)depth + 1 < branch.size()) return false; + while (branch.size() > (size_t)depth && branch[depth]) { + branch.pop_back(); + if (depth == 0) return false; + --depth; + } + if (branch.size() <= (size_t)depth) branch.resize((size_t)depth + 1); + assert(!branch[depth]); + branch[depth] = true; + } + // And this check corresponds to the IsComplete() check on m_branch. + return branch.size() == 0 || (branch.size() == 1 && branch[0]); +} + +TaprootBuilder& TaprootBuilder::Add(int depth, const CScript& script, int leaf_version, bool track) +{ + assert((leaf_version & ~TAPROOT_LEAF_MASK) == 0); + if (!IsValid()) return *this; + /* Construct NodeInfo object with leaf hash and (if track is true) also leaf information. */ + NodeInfo node; + node.hash = (CHashWriter{HASHER_TAPLEAF} << uint8_t(leaf_version) << script).GetSHA256(); + if (track) node.leaves.emplace_back(LeafInfo{script, leaf_version, {}}); + /* Insert into the branch. */ + Insert(std::move(node), depth); + return *this; +} + +TaprootBuilder& TaprootBuilder::AddOmitted(int depth, const uint256& hash) +{ + if (!IsValid()) return *this; + /* Construct NodeInfo object with the hash directly, and insert it into the branch. */ + NodeInfo node; + node.hash = hash; + Insert(std::move(node), depth); + return *this; +} + +TaprootBuilder& TaprootBuilder::Finalize(const XOnlyPubKey& internal_key) +{ + /* Can only call this function when IsComplete() is true. */ + assert(IsComplete()); + m_internal_key = internal_key; + auto ret = m_internal_key.CreateTapTweak(m_branch.size() == 0 ? nullptr : &m_branch[0]->hash); + assert(ret.has_value()); + std::tie(m_output_key, m_parity) = *ret; + return *this; +} + +WitnessV1Taproot TaprootBuilder::GetOutput() { return WitnessV1Taproot{m_output_key}; } + +TaprootSpendData TaprootBuilder::GetSpendData() const +{ + TaprootSpendData spd; + spd.merkle_root = m_branch.size() == 0 ? uint256() : m_branch[0]->hash; + spd.internal_key = m_internal_key; + if (m_branch.size()) { + // If any script paths exist, they have been combined into the root m_branch[0] + // by now. Compute the control block for each of its tracked leaves, and put them in + // spd.scripts. + for (const auto& leaf : m_branch[0]->leaves) { + std::vector<unsigned char> control_block; + control_block.resize(TAPROOT_CONTROL_BASE_SIZE + TAPROOT_CONTROL_NODE_SIZE * leaf.merkle_branch.size()); + control_block[0] = leaf.leaf_version | (m_parity ? 1 : 0); + std::copy(m_internal_key.begin(), m_internal_key.end(), control_block.begin() + 1); + if (leaf.merkle_branch.size()) { + std::copy(leaf.merkle_branch[0].begin(), + leaf.merkle_branch[0].begin() + TAPROOT_CONTROL_NODE_SIZE * leaf.merkle_branch.size(), + control_block.begin() + TAPROOT_CONTROL_BASE_SIZE); + } + spd.scripts[{leaf.script, leaf.leaf_version}].insert(std::move(control_block)); + } + } + return spd; +} diff --git a/src/script/standard.h b/src/script/standard.h index d5d87392ad..285dd4c116 100644 --- a/src/script/standard.h +++ b/src/script/standard.h @@ -6,9 +6,12 @@ #ifndef BITCOIN_SCRIPT_STANDARD_H #define BITCOIN_SCRIPT_STANDARD_H +#include <pubkey.h> #include <script/interpreter.h> #include <uint256.h> +#include <util/hash_type.h> +#include <map> #include <string> #include <variant> @@ -18,70 +21,6 @@ class CKeyID; class CScript; struct ScriptHash; -template<typename HashType> -class BaseHash -{ -protected: - HashType m_hash; - -public: - BaseHash() : m_hash() {} - explicit BaseHash(const HashType& in) : m_hash(in) {} - - unsigned char* begin() - { - return m_hash.begin(); - } - - const unsigned char* begin() const - { - return m_hash.begin(); - } - - unsigned char* end() - { - return m_hash.end(); - } - - const unsigned char* end() const - { - return m_hash.end(); - } - - operator std::vector<unsigned char>() const - { - return std::vector<unsigned char>{m_hash.begin(), m_hash.end()}; - } - - std::string ToString() const - { - return m_hash.ToString(); - } - - bool operator==(const BaseHash<HashType>& other) const noexcept - { - return m_hash == other.m_hash; - } - - bool operator!=(const BaseHash<HashType>& other) const noexcept - { - return !(m_hash == other.m_hash); - } - - bool operator<(const BaseHash<HashType>& other) const noexcept - { - return m_hash < other.m_hash; - } - - size_t size() const - { - return m_hash.size(); - } - - unsigned char* data() { return m_hash.data(); } - const unsigned char* data() const { return m_hash.data(); } -}; - /** A reference to a CScript: the Hash160 of its serialization (see script.h) */ class CScriptID : public BaseHash<uint160> { @@ -176,6 +115,12 @@ struct WitnessV0KeyHash : public BaseHash<uint160> }; CKeyID ToKeyID(const WitnessV0KeyHash& key_hash); +struct WitnessV1Taproot : public XOnlyPubKey +{ + WitnessV1Taproot() : XOnlyPubKey() {} + explicit WitnessV1Taproot(const XOnlyPubKey& xpk) : XOnlyPubKey(xpk) {} +}; + //! CTxDestination subtype to encode any future Witness version struct WitnessUnknown { @@ -205,11 +150,11 @@ struct WitnessUnknown * * ScriptHash: TxoutType::SCRIPTHASH destination (P2SH) * * WitnessV0ScriptHash: TxoutType::WITNESS_V0_SCRIPTHASH destination (P2WSH) * * WitnessV0KeyHash: TxoutType::WITNESS_V0_KEYHASH destination (P2WPKH) - * * WitnessUnknown: TxoutType::WITNESS_UNKNOWN/WITNESS_V1_TAPROOT destination (P2W???) - * (taproot outputs do not require their own type as long as no wallet support exists) + * * WitnessV1Taproot: TxoutType::WITNESS_V1_TAPROOT destination (P2TR) + * * WitnessUnknown: TxoutType::WITNESS_UNKNOWN destination (P2W???) * A CTxDestination is the internal data type encoded in a bitcoin address */ -using CTxDestination = std::variant<CNoDestination, PKHash, ScriptHash, WitnessV0ScriptHash, WitnessV0KeyHash, WitnessUnknown>; +using CTxDestination = std::variant<CNoDestination, PKHash, ScriptHash, WitnessV0ScriptHash, WitnessV0KeyHash, WitnessV1Taproot, WitnessUnknown>; /** Check whether a CTxDestination is a CNoDestination. */ bool IsValidDestination(const CTxDestination& dest); @@ -247,6 +192,8 @@ bool ExtractDestination(const CScript& scriptPubKey, CTxDestination& addressRet) * Note: this function confuses destinations (a subset of CScripts that are * encodable as an address) with key identifiers (of keys involved in a * CScript), and its use should be phased out. + * + * TODO: from v23 ("addresses" and "reqSigs" deprecated) "ExtractDestinations" should be removed */ bool ExtractDestinations(const CScript& scriptPubKey, TxoutType& typeRet, std::vector<CTxDestination>& addressRet, int& nRequiredRet); @@ -263,4 +210,121 @@ CScript GetScriptForRawPubKey(const CPubKey& pubkey); /** Generate a multisig script. */ CScript GetScriptForMultisig(int nRequired, const std::vector<CPubKey>& keys); +struct ShortestVectorFirstComparator +{ + bool operator()(const std::vector<unsigned char>& a, const std::vector<unsigned char>& b) const + { + if (a.size() < b.size()) return true; + if (a.size() > b.size()) return false; + return a < b; + } +}; + +struct TaprootSpendData +{ + /** The BIP341 internal key. */ + XOnlyPubKey internal_key; + /** The Merkle root of the script tree (0 if no scripts). */ + uint256 merkle_root; + /** Map from (script, leaf_version) to (sets of) control blocks. + * The control blocks are sorted by size, so that the signing logic can + * easily prefer the cheapest one. */ + std::map<std::pair<CScript, int>, std::set<std::vector<unsigned char>, ShortestVectorFirstComparator>> scripts; + /** Merge other TaprootSpendData (for the same scriptPubKey) into this. */ + void Merge(TaprootSpendData other); +}; + +/** Utility class to construct Taproot outputs from internal key and script tree. */ +class TaprootBuilder +{ +private: + /** Information about a tracked leaf in the Merkle tree. */ + struct LeafInfo + { + CScript script; //!< The script. + int leaf_version; //!< The leaf version for that script. + std::vector<uint256> merkle_branch; //!< The hashing partners above this leaf. + }; + + /** Information associated with a node in the Merkle tree. */ + struct NodeInfo + { + /** Merkle hash of this node. */ + uint256 hash; + /** Tracked leaves underneath this node (either from the node itself, or its children). + * The merkle_branch field for each is the partners to get to *this* node. */ + std::vector<LeafInfo> leaves; + }; + /** Whether the builder is in a valid state so far. */ + bool m_valid = true; + + /** The current state of the builder. + * + * For each level in the tree, one NodeInfo object may be present. m_branch[0] + * is information about the root; further values are for deeper subtrees being + * explored. + * + * For every right branch taken to reach the position we're currently + * working in, there will be a (non-nullopt) entry in m_branch corresponding + * to the left branch at that level. + * + * For example, imagine this tree: - N0 - + * / \ + * N1 N2 + * / \ / \ + * A B C N3 + * / \ + * D E + * + * Initially, m_branch is empty. After processing leaf A, it would become + * {nullopt, nullopt, A}. When processing leaf B, an entry at level 2 already + * exists, and it would thus be combined with it to produce a level 1 one, + * resulting in {nullopt, N1}. Adding C and D takes us to {nullopt, N1, C} + * and {nullopt, N1, C, D} respectively. When E is processed, it is combined + * with D, and then C, and then N1, to produce the root, resulting in {N0}. + * + * This structure allows processing with just O(log n) overhead if the leaves + * are computed on the fly. + * + * As an invariant, there can never be nullopt entries at the end. There can + * also not be more than 128 entries (as that would mean more than 128 levels + * in the tree). The depth of newly added entries will always be at least + * equal to the current size of m_branch (otherwise it does not correspond + * to a depth-first traversal of a tree). m_branch is only empty if no entries + * have ever be processed. m_branch having length 1 corresponds to being done. + */ + std::vector<std::optional<NodeInfo>> m_branch; + + XOnlyPubKey m_internal_key; //!< The internal key, set when finalizing. + XOnlyPubKey m_output_key; //!< The output key, computed when finalizing. + bool m_parity; //!< The tweak parity, computed when finalizing. + + /** Combine information about a parent Merkle tree node from its child nodes. */ + static NodeInfo Combine(NodeInfo&& a, NodeInfo&& b); + /** Insert information about a node at a certain depth, and propagate information up. */ + void Insert(NodeInfo&& node, int depth); + +public: + /** Add a new script at a certain depth in the tree. Add() operations must be called + * in depth-first traversal order of binary tree. If track is true, it will be included in + * the GetSpendData() output. */ + TaprootBuilder& Add(int depth, const CScript& script, int leaf_version, bool track = true); + /** Like Add(), but for a Merkle node with a given hash to the tree. */ + TaprootBuilder& AddOmitted(int depth, const uint256& hash); + /** Finalize the construction. Can only be called when IsComplete() is true. + internal_key.IsFullyValid() must be true. */ + TaprootBuilder& Finalize(const XOnlyPubKey& internal_key); + + /** Return true if so far all input was valid. */ + bool IsValid() const { return m_valid; } + /** Return whether there were either no leaves, or the leaves form a Huffman tree. */ + bool IsComplete() const { return m_valid && (m_branch.size() == 0 || (m_branch.size() == 1 && m_branch[0].has_value())); } + /** Compute scriptPubKey (after Finalize()). */ + WitnessV1Taproot GetOutput(); + /** Check if a list of depths is legal (will lead to IsComplete()). */ + static bool ValidDepths(const std::vector<int>& depths); + /** Compute spending data (after Finalize()). */ + TaprootSpendData GetSpendData() const; +}; + #endif // BITCOIN_SCRIPT_STANDARD_H |