This page hosts a formal specification of Bitcoin Transaction using Kaitai Struct. This specification can be automatically translated into a variety of programming languages to get a parsing library.
All parsing code for C++11/STL generated by Kaitai Struct depends on the C++/STL runtime library. You have to install it before you can parse data.
For C++, the easiest way is to clone the runtime library sources and build them along with your project.
Using Kaitai Struct in C++/STL usually consists of 3 steps.
std::istream). One can open local file for that, or use existing std::string or char* buffer.
#include <fstream>
std::ifstream is("path/to/local/file.bin", std::ifstream::binary);
#include <sstream>
std::istringstream is(str);
#include <sstream>
const char buf[] = { ... };
std::string str(buf, sizeof buf);
std::istringstream is(str);
#include "kaitai/kaitaistream.h"
kaitai::kstream ks(&is);
bitcoin_transaction_t data(&ks);
After that, one can get various attributes from the structure by invoking getter methods like:
data.version() // => Version number.
#pragma once
// This is a generated file! Please edit source .ksy file and use kaitai-struct-compiler to rebuild
#include "kaitai/kaitaistruct.h"
#include <stdint.h>
#include <memory>
#include <vector>
#if KAITAI_STRUCT_VERSION < 9000L
#error "Incompatible Kaitai Struct C++/STL API: version 0.9 or later is required"
#endif
/**
* \sa https://bitcoin.org/en/developer-guide#transactions
* https://en.bitcoin.it/wiki/Transaction
* Source
*/
class bitcoin_transaction_t : public kaitai::kstruct {
public:
class vin_t;
class vout_t;
bitcoin_transaction_t(kaitai::kstream* p__io, kaitai::kstruct* p__parent = nullptr, bitcoin_transaction_t* p__root = nullptr);
private:
void _read();
void _clean_up();
public:
~bitcoin_transaction_t();
class vin_t : public kaitai::kstruct {
public:
class script_signature_t;
vin_t(kaitai::kstream* p__io, bitcoin_transaction_t* p__parent = nullptr, bitcoin_transaction_t* p__root = nullptr);
private:
void _read();
void _clean_up();
public:
~vin_t();
class script_signature_t : public kaitai::kstruct {
public:
class der_signature_t;
class public_key_t;
enum sighash_type_t {
SIGHASH_TYPE_SIGHASH_ALL = 1,
SIGHASH_TYPE_SIGHASH_NONE = 2,
SIGHASH_TYPE_SIGHASH_SINGLE = 3,
SIGHASH_TYPE_SIGHASH_ANYONECANPAY = 80
};
script_signature_t(kaitai::kstream* p__io, bitcoin_transaction_t::vin_t* p__parent = nullptr, bitcoin_transaction_t* p__root = nullptr);
private:
void _read();
void _clean_up();
public:
~script_signature_t();
class der_signature_t : public kaitai::kstruct {
public:
der_signature_t(kaitai::kstream* p__io, bitcoin_transaction_t::vin_t::script_signature_t* p__parent = nullptr, bitcoin_transaction_t* p__root = nullptr);
private:
void _read();
void _clean_up();
public:
~der_signature_t();
private:
std::string m_sequence;
uint8_t m_len_sig;
std::string m_sep_1;
uint8_t m_len_sig_r;
std::string m_sig_r;
std::string m_sep_2;
uint8_t m_len_sig_s;
std::string m_sig_s;
bitcoin_transaction_t* m__root;
bitcoin_transaction_t::vin_t::script_signature_t* m__parent;
public:
std::string sequence() const { return m_sequence; }
uint8_t len_sig() const { return m_len_sig; }
std::string sep_1() const { return m_sep_1; }
/**
* 'r' value's length.
*/
uint8_t len_sig_r() const { return m_len_sig_r; }
/**
* 'r' value of the ECDSA signature.
* \sa https://en.wikipedia.org/wiki/Elliptic_Curve_Digital_Signature_Algorithm Source
*/
std::string sig_r() const { return m_sig_r; }
std::string sep_2() const { return m_sep_2; }
/**
* 's' value's length.
*/
uint8_t len_sig_s() const { return m_len_sig_s; }
/**
* 's' value of the ECDSA signature.
* \sa https://en.wikipedia.org/wiki/Elliptic_Curve_Digital_Signature_Algorithm Source
*/
std::string sig_s() const { return m_sig_s; }
bitcoin_transaction_t* _root() const { return m__root; }
bitcoin_transaction_t::vin_t::script_signature_t* _parent() const { return m__parent; }
};
class public_key_t : public kaitai::kstruct {
public:
public_key_t(kaitai::kstream* p__io, bitcoin_transaction_t::vin_t::script_signature_t* p__parent = nullptr, bitcoin_transaction_t* p__root = nullptr);
private:
void _read();
void _clean_up();
public:
~public_key_t();
private:
uint8_t m_type;
std::string m_x;
std::string m_y;
bitcoin_transaction_t* m__root;
bitcoin_transaction_t::vin_t::script_signature_t* m__parent;
public:
uint8_t type() const { return m_type; }
/**
* 'x' coordinate of the public key on the elliptic curve.
*/
std::string x() const { return m_x; }
/**
* 'y' coordinate of the public key on the elliptic curve.
*/
std::string y() const { return m_y; }
bitcoin_transaction_t* _root() const { return m__root; }
bitcoin_transaction_t::vin_t::script_signature_t* _parent() const { return m__parent; }
};
private:
uint8_t m_len_sig_stack;
std::unique_ptr<der_signature_t> m_der_sig;
sighash_type_t m_sig_type;
uint8_t m_len_pubkey_stack;
std::unique_ptr<public_key_t> m_pubkey;
bitcoin_transaction_t* m__root;
bitcoin_transaction_t::vin_t* m__parent;
public:
uint8_t len_sig_stack() const { return m_len_sig_stack; }
/**
* DER-encoded ECDSA signature.
* \sa https://en.wikipedia.org/wiki/X.690#DER_encoding
* https://en.wikipedia.org/wiki/Elliptic_Curve_Digital_Signature_Algorithm
* Source
*/
der_signature_t* der_sig() const { return m_der_sig.get(); }
/**
* Type of signature.
*/
sighash_type_t sig_type() const { return m_sig_type; }
uint8_t len_pubkey_stack() const { return m_len_pubkey_stack; }
/**
* Public key (bitcoin address of the recipient).
*/
public_key_t* pubkey() const { return m_pubkey.get(); }
bitcoin_transaction_t* _root() const { return m__root; }
bitcoin_transaction_t::vin_t* _parent() const { return m__parent; }
};
private:
std::string m_txid;
uint32_t m_output_id;
uint8_t m_len_script;
std::unique_ptr<script_signature_t> m_script_sig;
std::string m_end_of_vin;
bitcoin_transaction_t* m__root;
bitcoin_transaction_t* m__parent;
std::string m__raw_script_sig;
std::unique_ptr<kaitai::kstream> m__io__raw_script_sig;
public:
/**
* Previous transaction hash.
*/
std::string txid() const { return m_txid; }
/**
* ID indexing an ouput of the transaction refered by txid.
* This output will be used as an input in the present transaction.
*/
uint32_t output_id() const { return m_output_id; }
/**
* ScriptSig's length.
*/
uint8_t len_script() const { return m_len_script; }
/**
* ScriptSig.
* \sa https://en.bitcoin.it/wiki/Transaction#Input
* https://en.bitcoin.it/wiki/Script
* Source
*/
script_signature_t* script_sig() const { return m_script_sig.get(); }
/**
* Magic number indicating the end of the current input.
*/
std::string end_of_vin() const { return m_end_of_vin; }
bitcoin_transaction_t* _root() const { return m__root; }
bitcoin_transaction_t* _parent() const { return m__parent; }
std::string _raw_script_sig() const { return m__raw_script_sig; }
kaitai::kstream* _io__raw_script_sig() const { return m__io__raw_script_sig.get(); }
};
class vout_t : public kaitai::kstruct {
public:
vout_t(kaitai::kstream* p__io, bitcoin_transaction_t* p__parent = nullptr, bitcoin_transaction_t* p__root = nullptr);
private:
void _read();
void _clean_up();
public:
~vout_t();
private:
uint64_t m_amount;
uint8_t m_len_script;
std::string m_script_pub_key;
bitcoin_transaction_t* m__root;
bitcoin_transaction_t* m__parent;
public:
/**
* Number of Satoshis to be transfered.
*/
uint64_t amount() const { return m_amount; }
/**
* ScriptPubKey's length.
*/
uint8_t len_script() const { return m_len_script; }
/**
* ScriptPubKey.
* \sa https://en.bitcoin.it/wiki/Transaction#Output
* https://en.bitcoin.it/wiki/Script
* Source
*/
std::string script_pub_key() const { return m_script_pub_key; }
bitcoin_transaction_t* _root() const { return m__root; }
bitcoin_transaction_t* _parent() const { return m__parent; }
};
private:
uint32_t m_version;
uint8_t m_num_vins;
std::unique_ptr<std::vector<std::unique_ptr<vin_t>>> m_vins;
uint8_t m_num_vouts;
std::unique_ptr<std::vector<std::unique_ptr<vout_t>>> m_vouts;
uint32_t m_locktime;
bitcoin_transaction_t* m__root;
kaitai::kstruct* m__parent;
public:
/**
* Version number.
*/
uint32_t version() const { return m_version; }
/**
* Number of input transactions.
*/
uint8_t num_vins() const { return m_num_vins; }
/**
* Input transactions.
* An input refers to an output from a previous transaction.
*/
std::vector<std::unique_ptr<vin_t>>* vins() const { return m_vins.get(); }
/**
* Number of output transactions.
*/
uint8_t num_vouts() const { return m_num_vouts; }
/**
* Output transactions.
*/
std::vector<std::unique_ptr<vout_t>>* vouts() const { return m_vouts.get(); }
uint32_t locktime() const { return m_locktime; }
bitcoin_transaction_t* _root() const { return m__root; }
kaitai::kstruct* _parent() const { return m__parent; }
};
// This is a generated file! Please edit source .ksy file and use kaitai-struct-compiler to rebuild
#include "bitcoin_transaction.h"
#include "kaitai/exceptions.h"
bitcoin_transaction_t::bitcoin_transaction_t(kaitai::kstream* p__io, kaitai::kstruct* p__parent, bitcoin_transaction_t* p__root) : kaitai::kstruct(p__io) {
m__parent = p__parent;
m__root = this;
m_vins = nullptr;
m_vouts = nullptr;
_read();
}
void bitcoin_transaction_t::_read() {
m_version = m__io->read_u4le();
m_num_vins = m__io->read_u1();
m_vins = std::unique_ptr<std::vector<std::unique_ptr<vin_t>>>(new std::vector<std::unique_ptr<vin_t>>());
const int l_vins = num_vins();
for (int i = 0; i < l_vins; i++) {
m_vins->push_back(std::move(std::unique_ptr<vin_t>(new vin_t(m__io, this, m__root))));
}
m_num_vouts = m__io->read_u1();
m_vouts = std::unique_ptr<std::vector<std::unique_ptr<vout_t>>>(new std::vector<std::unique_ptr<vout_t>>());
const int l_vouts = num_vouts();
for (int i = 0; i < l_vouts; i++) {
m_vouts->push_back(std::move(std::unique_ptr<vout_t>(new vout_t(m__io, this, m__root))));
}
m_locktime = m__io->read_u4le();
}
bitcoin_transaction_t::~bitcoin_transaction_t() {
_clean_up();
}
void bitcoin_transaction_t::_clean_up() {
}
bitcoin_transaction_t::vin_t::vin_t(kaitai::kstream* p__io, bitcoin_transaction_t* p__parent, bitcoin_transaction_t* p__root) : kaitai::kstruct(p__io) {
m__parent = p__parent;
m__root = p__root;
m_script_sig = nullptr;
m__io__raw_script_sig = nullptr;
_read();
}
void bitcoin_transaction_t::vin_t::_read() {
m_txid = m__io->read_bytes(32);
m_output_id = m__io->read_u4le();
m_len_script = m__io->read_u1();
m__raw_script_sig = m__io->read_bytes(len_script());
m__io__raw_script_sig = std::unique_ptr<kaitai::kstream>(new kaitai::kstream(m__raw_script_sig));
m_script_sig = std::unique_ptr<script_signature_t>(new script_signature_t(m__io__raw_script_sig.get(), this, m__root));
m_end_of_vin = m__io->read_bytes(4);
if (!(end_of_vin() == std::string("\xFF\xFF\xFF\xFF", 4))) {
throw kaitai::validation_not_equal_error<std::string>(std::string("\xFF\xFF\xFF\xFF", 4), end_of_vin(), _io(), std::string("/types/vin/seq/4"));
}
}
bitcoin_transaction_t::vin_t::~vin_t() {
_clean_up();
}
void bitcoin_transaction_t::vin_t::_clean_up() {
}
bitcoin_transaction_t::vin_t::script_signature_t::script_signature_t(kaitai::kstream* p__io, bitcoin_transaction_t::vin_t* p__parent, bitcoin_transaction_t* p__root) : kaitai::kstruct(p__io) {
m__parent = p__parent;
m__root = p__root;
m_der_sig = nullptr;
m_pubkey = nullptr;
_read();
}
void bitcoin_transaction_t::vin_t::script_signature_t::_read() {
m_len_sig_stack = m__io->read_u1();
m_der_sig = std::unique_ptr<der_signature_t>(new der_signature_t(m__io, this, m__root));
m_sig_type = static_cast<bitcoin_transaction_t::vin_t::script_signature_t::sighash_type_t>(m__io->read_u1());
m_len_pubkey_stack = m__io->read_u1();
m_pubkey = std::unique_ptr<public_key_t>(new public_key_t(m__io, this, m__root));
}
bitcoin_transaction_t::vin_t::script_signature_t::~script_signature_t() {
_clean_up();
}
void bitcoin_transaction_t::vin_t::script_signature_t::_clean_up() {
}
bitcoin_transaction_t::vin_t::script_signature_t::der_signature_t::der_signature_t(kaitai::kstream* p__io, bitcoin_transaction_t::vin_t::script_signature_t* p__parent, bitcoin_transaction_t* p__root) : kaitai::kstruct(p__io) {
m__parent = p__parent;
m__root = p__root;
_read();
}
void bitcoin_transaction_t::vin_t::script_signature_t::der_signature_t::_read() {
m_sequence = m__io->read_bytes(1);
if (!(sequence() == std::string("\x30", 1))) {
throw kaitai::validation_not_equal_error<std::string>(std::string("\x30", 1), sequence(), _io(), std::string("/types/vin/types/script_signature/types/der_signature/seq/0"));
}
m_len_sig = m__io->read_u1();
m_sep_1 = m__io->read_bytes(1);
if (!(sep_1() == std::string("\x02", 1))) {
throw kaitai::validation_not_equal_error<std::string>(std::string("\x02", 1), sep_1(), _io(), std::string("/types/vin/types/script_signature/types/der_signature/seq/2"));
}
m_len_sig_r = m__io->read_u1();
m_sig_r = m__io->read_bytes(len_sig_r());
m_sep_2 = m__io->read_bytes(1);
if (!(sep_2() == std::string("\x02", 1))) {
throw kaitai::validation_not_equal_error<std::string>(std::string("\x02", 1), sep_2(), _io(), std::string("/types/vin/types/script_signature/types/der_signature/seq/5"));
}
m_len_sig_s = m__io->read_u1();
m_sig_s = m__io->read_bytes(len_sig_s());
}
bitcoin_transaction_t::vin_t::script_signature_t::der_signature_t::~der_signature_t() {
_clean_up();
}
void bitcoin_transaction_t::vin_t::script_signature_t::der_signature_t::_clean_up() {
}
bitcoin_transaction_t::vin_t::script_signature_t::public_key_t::public_key_t(kaitai::kstream* p__io, bitcoin_transaction_t::vin_t::script_signature_t* p__parent, bitcoin_transaction_t* p__root) : kaitai::kstruct(p__io) {
m__parent = p__parent;
m__root = p__root;
_read();
}
void bitcoin_transaction_t::vin_t::script_signature_t::public_key_t::_read() {
m_type = m__io->read_u1();
m_x = m__io->read_bytes(32);
m_y = m__io->read_bytes(32);
}
bitcoin_transaction_t::vin_t::script_signature_t::public_key_t::~public_key_t() {
_clean_up();
}
void bitcoin_transaction_t::vin_t::script_signature_t::public_key_t::_clean_up() {
}
bitcoin_transaction_t::vout_t::vout_t(kaitai::kstream* p__io, bitcoin_transaction_t* p__parent, bitcoin_transaction_t* p__root) : kaitai::kstruct(p__io) {
m__parent = p__parent;
m__root = p__root;
_read();
}
void bitcoin_transaction_t::vout_t::_read() {
m_amount = m__io->read_u8le();
m_len_script = m__io->read_u1();
m_script_pub_key = m__io->read_bytes(len_script());
}
bitcoin_transaction_t::vout_t::~vout_t() {
_clean_up();
}
void bitcoin_transaction_t::vout_t::_clean_up() {
}