diff options
Diffstat (limited to 'src/script/standard.cpp')
| -rw-r--r-- | src/script/standard.cpp | 116 |
1 files changed, 112 insertions, 4 deletions
diff --git a/src/script/standard.cpp b/src/script/standard.cpp index 364fac3c84..a4b11cc0a9 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> @@ -155,15 +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; } @@ -242,8 +244,13 @@ bool ExtractDestination(const CScript& scriptPubKey, CTxDestination& addressRet) addressRet = hash; return true; } - case TxoutType::WITNESS_UNKNOWN: 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); @@ -329,6 +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); @@ -361,3 +373,99 @@ CScript GetScriptForMultisig(int nRequired, const std::vector<CPubKey>& keys) bool IsValidDestination(const CTxDestination& dest) { return dest.index() != 0; } + +/*static*/ TaprootBuilder::NodeInfo TaprootBuilder::Combine(NodeInfo&& a, NodeInfo&& b) +{ + NodeInfo ret; + /* 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 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) +{ + assert((leaf_version & ~TAPROOT_LEAF_MASK) == 0); + if (!IsValid()) return *this; + /* Construct NodeInfo object with leaf hash. */ + NodeInfo node; + node.hash = (CHashWriter{HASHER_TAPLEAF} << uint8_t(leaf_version) << script).GetSHA256(); + /* 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, std::ignore) = *ret; + return *this; +} + +WitnessV1Taproot TaprootBuilder::GetOutput() { return WitnessV1Taproot{m_output_key}; } |