diff options
Diffstat (limited to 'src/script/sign.h')
-rw-r--r-- | src/script/sign.h | 629 |
1 files changed, 608 insertions, 21 deletions
diff --git a/src/script/sign.h b/src/script/sign.h index cf3651c1de..d12d0b5874 100644 --- a/src/script/sign.h +++ b/src/script/sign.h @@ -6,7 +6,11 @@ #ifndef BITCOIN_SCRIPT_SIGN_H #define BITCOIN_SCRIPT_SIGN_H +#include <boost/optional.hpp> +#include <hash.h> +#include <pubkey.h> #include <script/interpreter.h> +#include <streams.h> class CKey; class CKeyID; @@ -21,9 +25,22 @@ class SigningProvider { public: virtual ~SigningProvider() {} - virtual bool GetCScript(const CScriptID &scriptid, CScript& script) const =0; - virtual bool GetPubKey(const CKeyID &address, CPubKey& pubkey) const =0; - virtual bool GetKey(const CKeyID &address, CKey& key) const =0; + virtual bool GetCScript(const CScriptID &scriptid, CScript& script) const { return false; } + virtual bool GetPubKey(const CKeyID &address, CPubKey& pubkey) const { return false; } + virtual bool GetKey(const CKeyID &address, CKey& key) const { return false; } +}; + +extern const SigningProvider& DUMMY_SIGNING_PROVIDER; + +class PublicOnlySigningProvider : public SigningProvider +{ +private: + const SigningProvider* m_provider; + +public: + PublicOnlySigningProvider(const SigningProvider* provider) : m_provider(provider) {} + bool GetCScript(const CScriptID &scriptid, CScript& script) const; + bool GetPubKey(const CKeyID &address, CPubKey& pubkey) const; }; /** Interface for signature creators. */ @@ -37,35 +54,606 @@ public: }; /** A signature creator for transactions. */ -class TransactionSignatureCreator : public BaseSignatureCreator { - const CTransaction* txTo; +class MutableTransactionSignatureCreator : public BaseSignatureCreator { + const CMutableTransaction* txTo; unsigned int nIn; int nHashType; CAmount amount; - const TransactionSignatureChecker checker; + const MutableTransactionSignatureChecker checker; public: - TransactionSignatureCreator(const CTransaction* txToIn, unsigned int nInIn, const CAmount& amountIn, int nHashTypeIn=SIGHASH_ALL); + MutableTransactionSignatureCreator(const CMutableTransaction* txToIn, unsigned int nInIn, const CAmount& amountIn, int nHashTypeIn = SIGHASH_ALL); const BaseSignatureChecker& Checker() const override { return checker; } bool CreateSig(const SigningProvider& provider, std::vector<unsigned char>& vchSig, const CKeyID& keyid, const CScript& scriptCode, SigVersion sigversion) const override; }; -class MutableTransactionSignatureCreator : public TransactionSignatureCreator { - CTransaction tx; - -public: - MutableTransactionSignatureCreator(const CMutableTransaction* txToIn, unsigned int nInIn, const CAmount& amountIn, int nHashTypeIn) : TransactionSignatureCreator(&tx, nInIn, amountIn, nHashTypeIn), tx(*txToIn) {} -}; - /** A signature creator that just produces 72-byte empty signatures. */ extern const BaseSignatureCreator& DUMMY_SIGNATURE_CREATOR; +typedef std::pair<CPubKey, std::vector<unsigned char>> SigPair; + +// This struct contains information from a transaction input and also contains signatures for that input. +// The information contained here can be used to create a signature and is also filled by ProduceSignature +// in order to construct final scriptSigs and scriptWitnesses. struct SignatureData { - CScript scriptSig; - CScriptWitness scriptWitness; + bool complete = false; ///< Stores whether the scriptSig and scriptWitness are complete + bool witness = false; ///< Stores whether the input this SigData corresponds to is a witness input + CScript scriptSig; ///< The scriptSig of an input. Contains complete signatures or the traditional partial signatures format + CScript redeem_script; ///< The redeemScript (if any) for the input + CScript witness_script; ///< The witnessScript (if any) for the input. witnessScripts are used in P2WSH outputs. + CScriptWitness scriptWitness; ///< The scriptWitness of an input. Contains complete signatures or the traditional partial signatures format. scriptWitness is part of a transaction input per BIP 144. + std::map<CKeyID, SigPair> signatures; ///< BIP 174 style partial signatures for the input. May contain all signatures necessary for producing a final scriptSig or scriptWitness. + std::map<CKeyID, CPubKey> misc_pubkeys; SignatureData() {} explicit SignatureData(const CScript& script) : scriptSig(script) {} + void MergeSignatureData(SignatureData sigdata); +}; + +// Magic bytes +static constexpr uint8_t PSBT_MAGIC_BYTES[5] = {'p', 's', 'b', 't', 0xff}; + +// Global types +static constexpr uint8_t PSBT_GLOBAL_UNSIGNED_TX = 0x00; + +// Input types +static constexpr uint8_t PSBT_IN_NON_WITNESS_UTXO = 0x00; +static constexpr uint8_t PSBT_IN_WITNESS_UTXO = 0x01; +static constexpr uint8_t PSBT_IN_PARTIAL_SIG = 0x02; +static constexpr uint8_t PSBT_IN_SIGHASH = 0x03; +static constexpr uint8_t PSBT_IN_REDEEMSCRIPT = 0x04; +static constexpr uint8_t PSBT_IN_WITNESSSCRIPT = 0x05; +static constexpr uint8_t PSBT_IN_BIP32_DERIVATION = 0x06; +static constexpr uint8_t PSBT_IN_SCRIPTSIG = 0x07; +static constexpr uint8_t PSBT_IN_SCRIPTWITNESS = 0x08; + +// Output types +static constexpr uint8_t PSBT_OUT_REDEEMSCRIPT = 0x00; +static constexpr uint8_t PSBT_OUT_WITNESSSCRIPT = 0x01; +static constexpr uint8_t PSBT_OUT_BIP32_DERIVATION = 0x02; + +// The separator is 0x00. Reading this in means that the unserializer can interpret it +// as a 0 length key which indicates that this is the separator. The separator has no value. +static constexpr uint8_t PSBT_SEPARATOR = 0x00; + +// Takes a stream and multiple arguments and serializes them as if first serialized into a vector and then into the stream +// The resulting output into the stream has the total serialized length of all of the objects followed by all objects concatenated with each other. +template<typename Stream, typename... X> +void SerializeToVector(Stream& s, const X&... args) +{ + WriteCompactSize(s, GetSerializeSizeMany(s, args...)); + SerializeMany(s, args...); +} + +// Takes a stream and multiple arguments and unserializes them first as a vector then each object individually in the order provided in the arguments +template<typename Stream, typename... X> +void UnserializeFromVector(Stream& s, X&... args) +{ + size_t expected_size = ReadCompactSize(s); + size_t remaining_before = s.size(); + UnserializeMany(s, args...); + size_t remaining_after = s.size(); + if (remaining_after + expected_size != remaining_before) { + throw std::ios_base::failure("Size of value was not the stated size"); + } +} + +// Deserialize HD keypaths into a map +template<typename Stream> +void DeserializeHDKeypaths(Stream& s, const std::vector<unsigned char>& key, std::map<CPubKey, std::vector<uint32_t>>& hd_keypaths) +{ + // Make sure that the key is the size of pubkey + 1 + if (key.size() != CPubKey::PUBLIC_KEY_SIZE + 1 && key.size() != CPubKey::COMPRESSED_PUBLIC_KEY_SIZE + 1) { + throw std::ios_base::failure("Size of key was not the expected size for the type BIP32 keypath"); + } + // Read in the pubkey from key + CPubKey pubkey(key.begin() + 1, key.end()); + if (!pubkey.IsFullyValid()) { + throw std::ios_base::failure("Invalid pubkey"); + } + if (hd_keypaths.count(pubkey) > 0) { + throw std::ios_base::failure("Duplicate Key, pubkey derivation path already provided"); + } + + // Read in key path + uint64_t value_len = ReadCompactSize(s); + std::vector<uint32_t> keypath; + for (unsigned int i = 0; i < value_len; i += sizeof(uint32_t)) { + uint32_t index; + s >> index; + keypath.push_back(index); + } + + // Add to map + hd_keypaths.emplace(pubkey, keypath); +} + +// Serialize HD keypaths to a stream from a map +template<typename Stream> +void SerializeHDKeypaths(Stream& s, const std::map<CPubKey, std::vector<uint32_t>>& hd_keypaths, uint8_t type) +{ + for (auto keypath_pair : hd_keypaths) { + SerializeToVector(s, type, MakeSpan(keypath_pair.first)); + WriteCompactSize(s, keypath_pair.second.size() * sizeof(uint32_t)); + for (auto& path : keypath_pair.second) { + s << path; + } + } +} + +/** A structure for PSBTs which contain per-input information */ +struct PSBTInput +{ + CTransactionRef non_witness_utxo; + CTxOut witness_utxo; + CScript redeem_script; + CScript witness_script; + CScript final_script_sig; + CScriptWitness final_script_witness; + std::map<CPubKey, std::vector<uint32_t>> hd_keypaths; + std::map<CKeyID, SigPair> partial_sigs; + std::map<std::vector<unsigned char>, std::vector<unsigned char>> unknown; + int sighash_type = 0; + + bool IsNull() const; + void FillSignatureData(SignatureData& sigdata) const; + void FromSignatureData(const SignatureData& sigdata); + void Merge(const PSBTInput& input); + bool IsSane() const; + PSBTInput() {} + + template <typename Stream> + inline void Serialize(Stream& s) const { + // Write the utxo + // If there is a non-witness utxo, then don't add the witness one. + if (non_witness_utxo) { + SerializeToVector(s, PSBT_IN_NON_WITNESS_UTXO); + SerializeToVector(s, non_witness_utxo); + } else if (!witness_utxo.IsNull()) { + SerializeToVector(s, PSBT_IN_WITNESS_UTXO); + SerializeToVector(s, witness_utxo); + } + + if (final_script_sig.empty() && final_script_witness.IsNull()) { + // Write any partial signatures + for (auto sig_pair : partial_sigs) { + SerializeToVector(s, PSBT_IN_PARTIAL_SIG, MakeSpan(sig_pair.second.first)); + s << sig_pair.second.second; + } + + // Write the sighash type + if (sighash_type > 0) { + SerializeToVector(s, PSBT_IN_SIGHASH); + SerializeToVector(s, sighash_type); + } + + // Write the redeem script + if (!redeem_script.empty()) { + SerializeToVector(s, PSBT_IN_REDEEMSCRIPT); + s << redeem_script; + } + + // Write the witness script + if (!witness_script.empty()) { + SerializeToVector(s, PSBT_IN_WITNESSSCRIPT); + s << witness_script; + } + + // Write any hd keypaths + SerializeHDKeypaths(s, hd_keypaths, PSBT_IN_BIP32_DERIVATION); + } + + // Write script sig + if (!final_script_sig.empty()) { + SerializeToVector(s, PSBT_IN_SCRIPTSIG); + s << final_script_sig; + } + // write script witness + if (!final_script_witness.IsNull()) { + SerializeToVector(s, PSBT_IN_SCRIPTWITNESS); + SerializeToVector(s, final_script_witness.stack); + } + + // Write unknown things + for (auto& entry : unknown) { + s << entry.first; + s << entry.second; + } + + s << PSBT_SEPARATOR; + } + + + template <typename Stream> + inline void Unserialize(Stream& s) { + // Read loop + while(!s.empty()) { + // Read + std::vector<unsigned char> key; + s >> key; + + // the key is empty if that was actually a separator byte + // This is a special case for key lengths 0 as those are not allowed (except for separator) + if (key.empty()) return; + + // First byte of key is the type + unsigned char type = key[0]; + + // Do stuff based on type + switch(type) { + case PSBT_IN_NON_WITNESS_UTXO: + if (non_witness_utxo) { + throw std::ios_base::failure("Duplicate Key, input non-witness utxo already provided"); + } else if (key.size() != 1) { + throw std::ios_base::failure("Non-witness utxo key is more than one byte type"); + } + UnserializeFromVector(s, non_witness_utxo); + break; + case PSBT_IN_WITNESS_UTXO: + if (!witness_utxo.IsNull()) { + throw std::ios_base::failure("Duplicate Key, input witness utxo already provided"); + } else if (key.size() != 1) { + throw std::ios_base::failure("Witness utxo key is more than one byte type"); + } + UnserializeFromVector(s, witness_utxo); + break; + case PSBT_IN_PARTIAL_SIG: + { + // Make sure that the key is the size of pubkey + 1 + if (key.size() != CPubKey::PUBLIC_KEY_SIZE + 1 && key.size() != CPubKey::COMPRESSED_PUBLIC_KEY_SIZE + 1) { + throw std::ios_base::failure("Size of key was not the expected size for the type partial signature pubkey"); + } + // Read in the pubkey from key + CPubKey pubkey(key.begin() + 1, key.end()); + if (!pubkey.IsFullyValid()) { + throw std::ios_base::failure("Invalid pubkey"); + } + if (partial_sigs.count(pubkey.GetID()) > 0) { + throw std::ios_base::failure("Duplicate Key, input partial signature for pubkey already provided"); + } + + // Read in the signature from value + std::vector<unsigned char> sig; + s >> sig; + + // Add to list + partial_sigs.emplace(pubkey.GetID(), SigPair(pubkey, std::move(sig))); + break; + } + case PSBT_IN_SIGHASH: + if (sighash_type > 0) { + throw std::ios_base::failure("Duplicate Key, input sighash type already provided"); + } else if (key.size() != 1) { + throw std::ios_base::failure("Sighash type key is more than one byte type"); + } + UnserializeFromVector(s, sighash_type); + break; + case PSBT_IN_REDEEMSCRIPT: + { + if (!redeem_script.empty()) { + throw std::ios_base::failure("Duplicate Key, input redeemScript already provided"); + } else if (key.size() != 1) { + throw std::ios_base::failure("Input redeemScript key is more than one byte type"); + } + s >> redeem_script; + break; + } + case PSBT_IN_WITNESSSCRIPT: + { + if (!witness_script.empty()) { + throw std::ios_base::failure("Duplicate Key, input witnessScript already provided"); + } else if (key.size() != 1) { + throw std::ios_base::failure("Input witnessScript key is more than one byte type"); + } + s >> witness_script; + break; + } + case PSBT_IN_BIP32_DERIVATION: + { + DeserializeHDKeypaths(s, key, hd_keypaths); + break; + } + case PSBT_IN_SCRIPTSIG: + { + if (!final_script_sig.empty()) { + throw std::ios_base::failure("Duplicate Key, input final scriptSig already provided"); + } else if (key.size() != 1) { + throw std::ios_base::failure("Final scriptSig key is more than one byte type"); + } + s >> final_script_sig; + break; + } + case PSBT_IN_SCRIPTWITNESS: + { + if (!final_script_witness.IsNull()) { + throw std::ios_base::failure("Duplicate Key, input final scriptWitness already provided"); + } else if (key.size() != 1) { + throw std::ios_base::failure("Final scriptWitness key is more than one byte type"); + } + UnserializeFromVector(s, final_script_witness.stack); + break; + } + // Unknown stuff + default: + if (unknown.count(key) > 0) { + throw std::ios_base::failure("Duplicate Key, key for unknown value already provided"); + } + // Read in the value + std::vector<unsigned char> val_bytes; + s >> val_bytes; + unknown.emplace(std::move(key), std::move(val_bytes)); + break; + } + } + } + + template <typename Stream> + PSBTInput(deserialize_type, Stream& s) { + Unserialize(s); + } +}; + +/** A structure for PSBTs which contains per output information */ +struct PSBTOutput +{ + CScript redeem_script; + CScript witness_script; + std::map<CPubKey, std::vector<uint32_t>> hd_keypaths; + std::map<std::vector<unsigned char>, std::vector<unsigned char>> unknown; + + bool IsNull() const; + void FillSignatureData(SignatureData& sigdata) const; + void FromSignatureData(const SignatureData& sigdata); + void Merge(const PSBTOutput& output); + bool IsSane() const; + PSBTOutput() {} + + template <typename Stream> + inline void Serialize(Stream& s) const { + // Write the redeem script + if (!redeem_script.empty()) { + SerializeToVector(s, PSBT_OUT_REDEEMSCRIPT); + s << redeem_script; + } + + // Write the witness script + if (!witness_script.empty()) { + SerializeToVector(s, PSBT_OUT_WITNESSSCRIPT); + s << witness_script; + } + + // Write any hd keypaths + SerializeHDKeypaths(s, hd_keypaths, PSBT_OUT_BIP32_DERIVATION); + + // Write unknown things + for (auto& entry : unknown) { + s << entry.first; + s << entry.second; + } + + s << PSBT_SEPARATOR; + } + + + template <typename Stream> + inline void Unserialize(Stream& s) { + // Read loop + while(!s.empty()) { + // Read + std::vector<unsigned char> key; + s >> key; + + // the key is empty if that was actually a separator byte + // This is a special case for key lengths 0 as those are not allowed (except for separator) + if (key.empty()) return; + + // First byte of key is the type + unsigned char type = key[0]; + + // Do stuff based on type + switch(type) { + case PSBT_OUT_REDEEMSCRIPT: + { + if (!redeem_script.empty()) { + throw std::ios_base::failure("Duplicate Key, output redeemScript already provided"); + } else if (key.size() != 1) { + throw std::ios_base::failure("Output redeemScript key is more than one byte type"); + } + s >> redeem_script; + break; + } + case PSBT_OUT_WITNESSSCRIPT: + { + if (!witness_script.empty()) { + throw std::ios_base::failure("Duplicate Key, output witnessScript already provided"); + } else if (key.size() != 1) { + throw std::ios_base::failure("Output witnessScript key is more than one byte type"); + } + s >> witness_script; + break; + } + case PSBT_OUT_BIP32_DERIVATION: + { + DeserializeHDKeypaths(s, key, hd_keypaths); + break; + } + // Unknown stuff + default: { + if (unknown.count(key) > 0) { + throw std::ios_base::failure("Duplicate Key, key for unknown value already provided"); + } + // Read in the value + std::vector<unsigned char> val_bytes; + s >> val_bytes; + unknown.emplace(std::move(key), std::move(val_bytes)); + break; + } + } + } + } + + template <typename Stream> + PSBTOutput(deserialize_type, Stream& s) { + Unserialize(s); + } +}; + +/** A version of CTransaction with the PSBT format*/ +struct PartiallySignedTransaction +{ + boost::optional<CMutableTransaction> tx; + std::vector<PSBTInput> inputs; + std::vector<PSBTOutput> outputs; + std::map<std::vector<unsigned char>, std::vector<unsigned char>> unknown; + + bool IsNull() const; + void Merge(const PartiallySignedTransaction& psbt); + bool IsSane() const; + PartiallySignedTransaction() {} + PartiallySignedTransaction(const PartiallySignedTransaction& psbt_in) : tx(psbt_in.tx), inputs(psbt_in.inputs), outputs(psbt_in.outputs), unknown(psbt_in.unknown) {} + + // Only checks if they refer to the same transaction + friend bool operator==(const PartiallySignedTransaction& a, const PartiallySignedTransaction &b) + { + return a.tx->GetHash() == b.tx->GetHash(); + } + friend bool operator!=(const PartiallySignedTransaction& a, const PartiallySignedTransaction &b) + { + return !(a == b); + } + + template <typename Stream> + inline void Serialize(Stream& s) const { + + // magic bytes + s << PSBT_MAGIC_BYTES; + + // unsigned tx flag + SerializeToVector(s, PSBT_GLOBAL_UNSIGNED_TX); + + // Write serialized tx to a stream + SerializeToVector(s, *tx); + + // Write the unknown things + for (auto& entry : unknown) { + s << entry.first; + s << entry.second; + } + + // Separator + s << PSBT_SEPARATOR; + + // Write inputs + for (const PSBTInput& input : inputs) { + s << input; + } + // Write outputs + for (const PSBTOutput& output : outputs) { + s << output; + } + } + + + template <typename Stream> + inline void Unserialize(Stream& s) { + // Read the magic bytes + uint8_t magic[5]; + s >> magic; + if (!std::equal(magic, magic + 5, PSBT_MAGIC_BYTES)) { + throw std::ios_base::failure("Invalid PSBT magic bytes"); + } + + // Read global data + while(!s.empty()) { + // Read + std::vector<unsigned char> key; + s >> key; + + // the key is empty if that was actually a separator byte + // This is a special case for key lengths 0 as those are not allowed (except for separator) + if (key.empty()) break; + + // First byte of key is the type + unsigned char type = key[0]; + + // Do stuff based on type + switch(type) { + case PSBT_GLOBAL_UNSIGNED_TX: + { + if (tx) { + throw std::ios_base::failure("Duplicate Key, unsigned tx already provided"); + } else if (key.size() != 1) { + throw std::ios_base::failure("Global unsigned tx key is more than one byte type"); + } + CMutableTransaction mtx; + UnserializeFromVector(s, mtx); + tx = std::move(mtx); + // Make sure that all scriptSigs and scriptWitnesses are empty + for (const CTxIn& txin : tx->vin) { + if (!txin.scriptSig.empty() || !txin.scriptWitness.IsNull()) { + throw std::ios_base::failure("Unsigned tx does not have empty scriptSigs and scriptWitnesses."); + } + } + break; + } + // Unknown stuff + default: { + if (unknown.count(key) > 0) { + throw std::ios_base::failure("Duplicate Key, key for unknown value already provided"); + } + // Read in the value + std::vector<unsigned char> val_bytes; + s >> val_bytes; + unknown.emplace(std::move(key), std::move(val_bytes)); + } + } + } + + // Make sure that we got an unsigned tx + if (!tx) { + throw std::ios_base::failure("No unsigned transcation was provided"); + } + + // Read input data + unsigned int i = 0; + while (!s.empty() && i < tx->vin.size()) { + PSBTInput input; + s >> input; + inputs.push_back(input); + + // Make sure the non-witness utxo matches the outpoint + if (input.non_witness_utxo && input.non_witness_utxo->GetHash() != tx->vin[i].prevout.hash) { + throw std::ios_base::failure("Non-witness UTXO does not match outpoint hash"); + } + ++i; + } + // Make sure that the number of inputs matches the number of inputs in the transaction + if (inputs.size() != tx->vin.size()) { + throw std::ios_base::failure("Inputs provided does not match the number of inputs in transaction."); + } + + // Read output data + i = 0; + while (!s.empty() && i < tx->vout.size()) { + PSBTOutput output; + s >> output; + outputs.push_back(output); + ++i; + } + // Make sure that the number of outputs matches the number of outputs in the transaction + if (outputs.size() != tx->vout.size()) { + throw std::ios_base::failure("Outputs provided does not match the number of outputs in transaction."); + } + // Sanity check + if (!IsSane()) { + throw std::ios_base::failure("PSBT is not sane."); + } + } + + template <typename Stream> + PartiallySignedTransaction(deserialize_type, Stream& s) { + Unserialize(s); + } }; /** Produce a script signature using a generic signature creator. */ @@ -75,12 +663,11 @@ bool ProduceSignature(const SigningProvider& provider, const BaseSignatureCreato bool SignSignature(const SigningProvider &provider, const CScript& fromPubKey, CMutableTransaction& txTo, unsigned int nIn, const CAmount& amount, int nHashType); bool SignSignature(const SigningProvider &provider, const CTransaction& txFrom, CMutableTransaction& txTo, unsigned int nIn, int nHashType); -/** Combine two script signatures using a generic signature checker, intelligently, possibly with OP_0 placeholders. */ -SignatureData CombineSignatures(const CScript& scriptPubKey, const BaseSignatureChecker& checker, const SignatureData& scriptSig1, const SignatureData& scriptSig2); +/** Signs a PSBTInput */ +bool SignPSBTInput(const SigningProvider& provider, const CMutableTransaction& tx, PSBTInput& input, SignatureData& sigdata, int index, int sighash = 1); -/** Extract signature data from a transaction, and insert it. */ -SignatureData DataFromTransaction(const CMutableTransaction& tx, unsigned int nIn); -void UpdateTransaction(CMutableTransaction& tx, unsigned int nIn, const SignatureData& data); +/** Extract signature data from a transaction input, and insert it. */ +SignatureData DataFromTransaction(const CMutableTransaction& tx, unsigned int nIn, const CTxOut& txout); void UpdateInput(CTxIn& input, const SignatureData& data); /* Check whether we know how to sign for an output like this, assuming we |