dash/src/psbt.h
Wladimir J. van der Laan 81b8eb4083
Merge #12461: scripted-diff: Rename key size consts to be relative to their class
0580f86bb48004b797d4cb6273e7ffee0b0a0584 Fixup whitespace (Ben Woosley)
47101bbb27d0e13ea2b40ce1c7ff0dba9030f369 scripted-diff: Rename CPubKey and CKey::*_KEY_SIZE and COMPRESSED_*_KEY_SIZE (Ben Woosley)

Pull request description:

  ~~And introduce CPubKeySig to host code relative to key sigs.~~

ACKs for top commit:
  meshcollider:
    utACK 0580f86bb4

Tree-SHA512: 29aa0be54912358b138e391b9db78639786f56580493e590ec9f773c0e1b421740133d05a79be247c7ee57e71c9c9e41b9cb54088cb3c0e3f813f74f0895287b
2021-08-11 00:05:22 +03:00

507 lines
18 KiB
C++

// Copyright (c) 2009-2018 The Bitcoin Core developers
// Distributed under the MIT software license, see the accompanying
// file COPYING or http://www.opensource.org/licenses/mit-license.php.
#ifndef BITCOIN_PSBT_H
#define BITCOIN_PSBT_H
#include <attributes.h>
#include <node/transaction.h>
#include <primitives/transaction.h>
#include <pubkey.h>
#include <script/sign.h>
// 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_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_BIP32_DERIVATION = 0x06;
static constexpr uint8_t PSBT_IN_SCRIPTSIG = 0x07;
// Output types
static constexpr uint8_t PSBT_OUT_REDEEMSCRIPT = 0x00;
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;
/** A structure for PSBTs which contain per-input information */
struct PSBTInput
{
CTransactionRef non_witness_utxo;
CScript redeem_script;
CScript final_script_sig;
std::map<CPubKey, KeyOriginInfo> 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 (non_witness_utxo) {
SerializeToVector(s, PSBT_IN_NON_WITNESS_UTXO);
SerializeToVector(s, non_witness_utxo);
}
if (final_script_sig.empty()) {
// 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 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 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
bool found_sep = false;
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()) {
found_sep = true;
break;
}
// 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_PARTIAL_SIG:
{
// Make sure that the key is the size of pubkey + 1
if (key.size() != CPubKey::SIZE + 1 && key.size() != CPubKey::COMPRESSED_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_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;
}
// 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;
}
}
if (!found_sep) {
throw std::ios_base::failure("Separator is missing at the end of an input map");
}
}
template <typename Stream>
PSBTInput(deserialize_type, Stream& s) {
Unserialize(s);
}
};
/** A structure for PSBTs which contains per output information */
struct PSBTOutput
{
CScript redeem_script;
std::map<CPubKey, KeyOriginInfo> 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 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
bool found_sep = false;
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()) {
found_sep = true;
break;
}
// 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_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;
}
}
}
if (!found_sep) {
throw std::ios_base::failure("Separator is missing at the end of an output map");
}
}
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;
/** Merge psbt into this. The two psbts must have the same underlying CTransaction (i.e. the
* same actual Bitcoin transaction.) Returns true if the merge succeeded, false otherwise. */
[[nodiscard]] bool Merge(const PartiallySignedTransaction& psbt);
bool IsSane() const;
bool AddInput(const CTxIn& txin, PSBTInput& psbtin);
bool AddOutput(const CTxOut& txout, const PSBTOutput& psbtout);
PartiallySignedTransaction() {}
PartiallySignedTransaction(const PartiallySignedTransaction& psbt_in) : tx(psbt_in.tx), inputs(psbt_in.inputs), outputs(psbt_in.outputs), unknown(psbt_in.unknown) {}
/**
* Finds the UTXO for a given input index
*
* @param[out] utxo The UTXO of the input if found
* @param[in] input_index Index of the input to retrieve the UTXO of
* @return Whether the UTXO for the specified input was found
*/
bool GetInputUTXO(CTxOut& utxo, int input_index) const;
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
bool found_sep = false;
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()) {
found_sep = true;
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 are empty
for (const CTxIn& txin : tx->vin) {
if (!txin.scriptSig.empty()) {
throw std::ios_base::failure("Unsigned tx does not have empty scriptSigs.");
}
}
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));
}
}
}
if (!found_sep) {
throw std::ios_base::failure("Separator is missing at the end of the global map");
}
// 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);
}
};
/** Signs a PSBTInput, verifying that all provided data matches what is being signed. */
bool SignPSBTInput(const SigningProvider& provider, const CMutableTransaction& tx, PSBTInput& input, int index, int sighash = SIGHASH_ALL);
/**
* Finalizes a PSBT if possible, combining partial signatures.
*
* @param[in,out] &psbtx reference to PartiallySignedTransaction to finalize
* return True if the PSBT is now complete, false otherwise
*/
bool FinalizePSBT(PartiallySignedTransaction& psbtx);
/**
* Finalizes a PSBT if possible, and extracts it to a CMutableTransaction if it could be finalized.
*
* @param[in] &psbtx reference to PartiallySignedTransaction
* @param[out] result CMutableTransaction representing the complete transaction, if successful
* @return True if we successfully extracted the transaction, false otherwise
*/
bool FinalizeAndExtractPSBT(PartiallySignedTransaction& psbtx, CMutableTransaction& result);
/**
* Combines PSBTs with the same underlying transaction, resulting in a single PSBT with all partial signatures from each input.
*
* @param[out] &out the combined PSBT, if successful
* @param[out] &error reference to TransactionError to fill with error info on failure
* @param[in] psbtxs the PSBTs to combine
* @return True if we successfully combined the transactions, false if they were not compatible
*/
bool CombinePSBTs(PartiallySignedTransaction& out, TransactionError& error, const std::vector<PartiallySignedTransaction>& psbtxs);
#endif // BITCOIN_PSBT_H