b0899204d9
This change updates the doc.go documentation file with the correct use
of the new (since 8eead5217d) API used
for passing additional options when creating new script engines.
Spotted by davec@
62 lines
2.4 KiB
Go
62 lines
2.4 KiB
Go
// Copyright (c) 2013 Conformal Systems LLC.
|
|
// Use of this source code is governed by an ISC
|
|
// license that can be found in the LICENSE file.
|
|
|
|
/*
|
|
Package btcscript implements bitcoin transaction scripts.
|
|
|
|
A complete description of the script language used by bitcoin can be found at
|
|
https://en.bitcoin.it/wiki/Script. The following only serves as a quick
|
|
overview to provide information on how to use the package.
|
|
|
|
This package provides data structures and functions to parse and execute
|
|
bitcoin transaction scripts.
|
|
|
|
Script Overview
|
|
|
|
Bitcoin transaction scripts are written in a stack-base, FORTH-like language.
|
|
|
|
The bitcoin script language consists of a number of opcodes which fall into
|
|
several categories such pushing and popping data to and from the stack,
|
|
performing basic and bitwise arithmetic, conditional branching, comparing
|
|
hashes, and checking cryptographic signatures. Scripts are processed from left
|
|
to right and intentionally do not provide loops.
|
|
|
|
The vast majority of Bitcoin scripts at the time of this writing are of several
|
|
standard forms which consist of a spender providing a public key and a signature
|
|
which proves the spender owns the associated private key. This information
|
|
is used to prove the the spender is authorized to perform the transaction.
|
|
|
|
One benefit of using a scripting language is added flexibility in specifying
|
|
what conditions must be met in order to spend bitcoins.
|
|
|
|
Usage
|
|
|
|
The usage of this package consists of creating a new script engine for a pair
|
|
of transaction inputs and outputs and using the engine to execute the scripts.
|
|
|
|
The following function is an example of how to create and execute a script
|
|
engine to validate a transaction.
|
|
|
|
// ValidateTx validates the txIdx'th input of tx. The output transaction
|
|
// corresponding to the this input is the txInIdx'th output of txIn. The
|
|
// block timestamp of tx is timestamp.
|
|
func ValidateTx(tx *btcwire.MsgTx, txIdx int, txIn *btcwire.MsgTx, txInIdx int, timestamp time.Time) {
|
|
pkScript := txIn.TxOut[txInIdx].PkScript
|
|
sigScript := tx.txIn[TxIdx]
|
|
var flags btcscript.ScriptFlags
|
|
if timestamp.After(btcscript.Bip16Activation) {
|
|
flags |= btcscript.ScriptBip16
|
|
}
|
|
engine, err := btcscript.NewScript(sigScript, pkScript, txInIdx,
|
|
tx, flags)
|
|
return engine.Execute()
|
|
}
|
|
|
|
Errors
|
|
|
|
Errors returned by this package are of the form btcscript.StackErrX where X
|
|
indicates the specific error. See Variables in the package documentation for a
|
|
full list.
|
|
*/
|
|
package btcscript
|