JSDoc: Class: Script

new Script(code, mutable)

Represents a input or output script.

Parameters:

Name	Type	Description
`code`	Buffer \| Array \| Object \| NakedScript	Array of script code or a serialized script Buffer.
`mutable`	Boolean	Whether the script will be changed in the future.

Properties:

Name	Type	Attributes	Description
`code`	Array		Script code.
`raw`	Buffer	<nullable>	Serialized script.
`redeem`	Script	<nullable>	Redeem script.
`mutable`	Boolean

Source:

bcoin/script.js, line 851

Methods

(static) array(value) → {Buffer}

Create a script array. Will convert Numbers and big numbers to a little-endian buffer while taking into account negative zero, minimaldata, etc.

Parameters:

Name	Type	Description
`value`	Buffer \| Number \| BN

Source:

bcoin/script.js, line 1884

Returns:

Type: Buffer

Example

assert.deepEqual(Script.array(0), new Buffer([]));
assert.deepEqual(Script.array(0xffee), new Buffer([0xee, 0xff]));
assert.deepEqual(Script.array(new bn(0xffee)), new Buffer([0xee, 0xff]));

(static) bool(value) → {Boolean}

Cast a big number or Buffer to a bool.

Parameters:

Name	Type	Description
`value`	BN \| Buffer

Source:

bcoin/script.js, line 1798

See:

CastToBool

Returns:

Type: Boolean

(static) checkLocktime(locktime, tx, index) → {Boolean}

Verify the nLockTime of a transaction.

Parameters:

Name	Type	Description
`locktime`	Number	Locktime to verify against (max=u32).
`tx`	TX	Transaction to verify.
`index`	Number	Index of input being verified (for IsFinal).

Source:

bcoin/script.js, line 1734

Returns:

Type: Boolean

(static) checkMinimal(value, flagsnullable) → {Boolean}

Check to see if a pushdata Buffer abides by minimaldata.

Parameters:

Name	Type	Attributes	Description
`value`	Buffer		Pushdata op from script code (must be from a deserialized script).
`flags`	Number	<nullable>

Source:

bcoin/script.js, line 2064

Returns:

Type: Boolean

(static) checkPush(value) → {Boolean}

Perform some range checking on the pushdatas (exactly what GetOp2 does). Note that this must be done during execution, not parsing.

Parameters:

Name	Type	Description
`value`	Buffer	Pushdata op from script code (must be from a deserialized script).

Source:

bcoin/script.js, line 2045

See:

GetOp2

Returns:

Type: Boolean

(static) checkSequence(sequence, tx, index) → {Boolean}

Verify the nSequence locktime of a transaction.

Parameters:

Name	Type	Description
`sequence`	Number	Locktime to verify against (max=u32).
`tx`	TX	Transaction to verify.
`index`	Number	Index of input being verified.

Source:

bcoin/script.js, line 1761

Returns:

Type: Boolean

(static) checksig(msg, sig, key, flagsnullable) → {Boolean}

Verify a signature, taking into account sighash type and whether the signature is historical.

Parameters:

Name	Type	Attributes	Description
`msg`	Buffer		Signature hash.
`sig`	Buffer
`key`	Buffer
`flags`	VerifyFlags	<nullable>	If none of VERIFY_DERSIG, VERIFY_LOW_S, or VERIFY_STRICTENC are enabled, the signature is treated as historical, allowing odd signature lengths and high S values.

Source:

bcoin/script.js, line 3962

Returns:

Type: Boolean

(static) concat(scripts) → {Array}

Concatenate scripts, inserting code separators in between them.

Parameters:

Name	Type	Description
`scripts`	Array.<Script>

Source:

bcoin/script.js, line 3935

Returns:

code

Type: Array

(static) createCommitment(hash) → {Script}

Create a witness block commitment.

Parameters:

Name	Type	Description
`hash`	Buffer

Source:

bcoin/script.js, line 2238

Returns:

Type: Script

(static) createMultisig(keys, m, n) → {Script}

Create a pay-to-multisig script.

Parameters:

Name	Type	Description
`keys`	Array.<Buffer>
`m`	Number
`n`	Number

Source:

bcoin/script.js, line 2167

Returns:

Type: Script

(static) createNulldata(flags) → {Script}

Create a nulldata/opreturn script.

Parameters:

Name	Type	Description
`flags`	Buffer

Source:

bcoin/script.js, line 2209

Returns:

Type: Script

(static) createOutputScript(options) → {Script}

Automatically build an output script from any number of options.

Parameters:

Name Type Description

options

Object

Properties

Name	Type	Attributes	Description
`address`	Base58Address	<nullable>	Base58 address to send to.
`flags`	Buffer	<nullable>	Nulldata flags.
`key`	Buffer	<nullable>	Key for pay-to-pubkey.
`keyHash`	Buffer	<nullable>	Key has for pay-to-pubkeyhash.
`keys`	Array.<Buffer>	<nullable>	Keys for pay-to-multisig.
`scriptHash`	Boolean \| Array.<Buffer>		Whether to create a scripthash

Source:

bcoin/script.js, line 2836

Returns:

Type: Script

Example

Script.createOutputScript({ address: '1HT7xU2Ngenf7D4yocz2SAcnNLW7rK8d4E' });

(static) createPubkey(key) → {Script}

Create a pay-to-pubkey script.

Parameters:

Name	Type	Description
`key`	Buffer

Source:

bcoin/script.js, line 2139

Returns:

Type: Script

(static) createPubkeyhash(hash) → {Script}

Create a pay-to-pubkeyhash script.

Parameters:

Name	Type	Description
`hash`	Buffer

Source:

bcoin/script.js, line 2149

Returns:

Type: Script

(static) createScripthash(hash) → {Script}

Create a pay-to-scripthash script.

Parameters:

Name	Type	Description
`hash`	Buffer

Source:

bcoin/script.js, line 2194

Returns:

Type: Script

(static) createWitnessProgram(version, data) → {Script}

Create a witness program.

Parameters:

Name	Type	Description
`version`	Number
`data`	Buffer

Source:

bcoin/script.js, line 2225

Returns:

Type: Script

(static) decode(buf) → {Array}

Decode a serialized script into script code. Note that the serialized script must not include the varint size before it. Note that this will apply hidden pushdata properties to each Buffer if the buffer was created from a non-standard pushdata.

This function does not do bounds checking on buffers because some jackass could do a direct push of 30 bytes with only 20 bytes after it. That script would be perfectly fine until it is executed. There are output scripts on the blockchain that can never be redeemed due to this, but they are in valid blocks, therefore we cannot fail parsing them.

Also note that this function uses reference Buffer slices. Larger buffer slices should never be passed in here.

Parameters:

Name	Type	Description
`buf`	Buffer	Serialized script.

Source:

bcoin/script.js, line 4044

Returns:

Script code.

Type: Array

(static) encode(code) → {Buffer}

Encode and serialize script code. This will not include the varint size at the start. This will correctly reserialize non-standard pushdata ops if the code was originally created from {Script.decode}. Otherwise, it will convert the code's pushdatas to minimaldata representations.

Parameters:

Name	Type	Description
`code`	Array	Script code.

Source:

bcoin/script.js, line 4110

Returns:

Serialized script.

Type: Buffer

(static) format(code) → {String}

Format script code into a human readable-string.

Parameters:

Name	Type	Description
`code`	Array

Source:

bcoin/script.js, line 3400

Returns:

Human-readable string.

Type: String

(static) fromString(items) → {Script}

Parse a formatted script string into a script object.

Parameters:

Name	Type	Description
`items`	String	Script string.

Source:

bcoin/script.js, line 3545

Throws:

Parse error.

Returns:

Type: Script

(static) fromSymbolic(items) → {Script}

Parse an array of opcodes and pushdatas (Buffers) with the opcodes as strings representing their symbolic name. Script.fromSymbolic(['OP_1', new Buffer([2]), 'OP_ADD']);

Parameters:

Name	Type	Description
`items`	Array	Array of strings and Buffers.

Source:

bcoin/script.js, line 3707

Throws:

Parse error on unknown opcode.

Returns:

Type: Script

(static) fromTestString(items) → {Script}

Parse a bitcoind test script string into a script object.

Parameters:

Name	Type	Description
`items`	String	Script string.

Source:

bcoin/script.js, line 3602

Throws:

Parse error.

Returns:

Type: Script

(static) getCoinbaseHeight() → {Number}

Get coinbase height.

Source:

bcoin/script.js, line 3045

Returns:

-1 if not present.

Type: Number

(static) getRedeem(code) → {Script|null}

Grab and deserialize the redeem script from script code.

Parameters:

Name	Type	Description
`code`	Array

Source:

bcoin/script.js, line 2267

Returns:

Redeem script.

Type: Script | null

(static) getSmall(index) → {Number}

Get a small integer from an opcode (OP_0-OP_16).

Parameters:

Name	Type	Description
`index`	Number

Source:

bcoin/script.js, line 3670

Returns:

Type: Number

(static) isCode(buf) → {Boolean}

Test a buffer to see if it is valid script code (no non-existent opcodes).

Parameters:

Name	Type	Description
`buf`	Buffer

Source:

bcoin/script.js, line 2100

Returns:

Type: Boolean

(static) isDummy(datanullable) → {Boolean}

Test whether the data element is a null dummy (a zero-length array).

Parameters:

Name	Type	Attributes	Description
`data`	Buffer	<nullable>

Source:

bcoin/script.js, line 3143

Returns:

Type: Boolean

(static) isHash(hashnullable) → {Boolean}

Test whether the data element is a ripemd160 hash.

Parameters:

Name	Type	Attributes	Description
`hash`	Buffer	<nullable>

Source:

bcoin/script.js, line 3111

Returns:

Type: Boolean

(static) isHashType(sig) → {Boolean}

Test a signature to see whether it contains a valid sighash type.

Parameters:

Name	Type	Description
`sig`	Buffer

Source:

bcoin/script.js, line 3357

Returns:

Type: Boolean

(static) isKey(keynullable) → {Boolean}

Test whether the data element is a public key. Note that this does not verify the format of the key, only the length.

Parameters:

Name	Type	Attributes	Description
`key`	Buffer	<nullable>

Source:

bcoin/script.js, line 3122

Returns:

Type: Boolean

(static) isKeyEncoding(key) → {Boolean}

Test whether the data element is a valid key.

Parameters:

Name	Type	Description
`key`	Buffer

Source:

bcoin/script.js, line 3191

Returns:

Type: Boolean

(static) isLowDER(sig) → {Boolean}

Test a signature to see whether it contains a low S value.

Parameters:

Name	Type	Description
`sig`	Buffer

Source:

bcoin/script.js, line 3380

Returns:

Type: Boolean

(static) isPush(valuenullable) → {Boolean}

Test whether an op is a buffer, also check for buffer underflows.

Parameters:

Name	Type	Attributes	Description
`value`	Buffer	<nullable>

Source:

bcoin/script.js, line 2031

Returns:

Type: Boolean

(static) isScript(obj) → {Boolean}

Test an object to see if it is a Script.

Parameters:

Name	Type	Description
`obj`	Object

Source:

bcoin/script.js, line 4198

Returns:

Type: Boolean

(static) isSignature(signullable) → {Boolean}

Test whether the data element is a signature. Note that this does not verify the format of the signature, only the length.

Parameters:

Name	Type	Attributes	Description
`sig`	Buffer	<nullable>

Source:

bcoin/script.js, line 3133

Returns:

Type: Boolean

(static) isSignatureEncoding(sig) → {Boolean}

Test a signature to see if it abides by BIP66.

Parameters:

Name	Type	Description
`sig`	Buffer

Source:

bcoin/script.js, line 3266

See:

https://github.com/bitcoin/bips/blob/master/bip-0066.mediawiki

Returns:

Type: Boolean

(static) isValidKey(key, flagsnullable) → {Boolean}

Test whether the data element is a valid key if VERIFY_STRICTENC is enabled.

Parameters:

Name	Type	Attributes	Description
`key`	Buffer
`flags`	VerifyFlags	<nullable>

Source:

bcoin/script.js, line 3168

Returns:

Type: Boolean

(static) isValidSignature(sig, flagsnullable) → {Boolean}

Test whether the data element is a valid signature based on the encoding, S value, and sighash type. Requires VERIFY_DERSIG|VERIFY_LOW_S|VERIFY_STRICTENC, VERIFY_LOW_S and VERIFY_STRING_ENC to be enabled respectively. Note that this will allow zero-length signatures.

Parameters:

Name	Type	Attributes	Description
`sig`	Buffer
`flags`	VerifyFlags	<nullable>

Source:

bcoin/script.js, line 3222

Returns:

Type: Boolean

(private, static) isZero(datanullable) → {Boolean}

Test whether the data element is a null dummy or an OP_0.

Parameters:

Name	Type	Attributes	Description
`data`	Buffer	<nullable>

Source:

bcoin/script.js, line 3154

Returns:

Type: Boolean

(static) num(value, flagsnullable, sizenullable) → {BN}

Create a CScriptNum.

Parameters:

Name	Type	Attributes	Description
`value`	Buffer
`flags`	Number	<nullable>	Script standard flags.
`size`	Number	<nullable>	Max size in bytes.

Source:

bcoin/script.js, line 1827

Throws:

ScriptError

Returns:

Type: BN

(static) parseScript(buf) → {Object}

Parse a serialized script, returning the "naked" representation of a Script object (the same properties, but it is not instantiated -- suitable as an options object for Script).

Parameters:

Name	Type	Description
`buf`	Buffer	Serialized script.

Source:

bcoin/script.js, line 4012

Returns:

Naked script object.

Type: Object

(static) sign(msg, key, type) → {Buffer}

Sign a message, appending the sighash type.

Parameters:

Name	Type	Description
`msg`	Buffer	Signature hash.
`key`	Buffer	Public key.
`type`	Number	Sighash type.

Source:

bcoin/script.js, line 3995

Returns:

signature

Type: Buffer

(static) toSmall(num) → {Number}

Convert a number to a small integer (OP_0-OP_16).

Parameters:

Name	Type	Description
`num`	Number

Source:

bcoin/script.js, line 3689

Returns:

opcode

Type: Number

(static) verify(input, witness, output, tx, i, flags) → {Boolean}

Verify an input and output script, and a witness if present.

Parameters:

Name	Type	Description
`input`	Script
`witness`	Witness
`output`	Script
`tx`	TX
`i`	Number
`flags`	VerifyFlags

Source:

bcoin/script.js, line 3745

Returns:

Type: Boolean

(static) verifyProgram(witness, output, flags, tx, i)

Verify a witness program. This runs after regular script execution if a witness program is present. It will convert the witness to a stack and execute the program.

Parameters:

Name	Type	Description
`witness`	Witness
`output`	Script
`flags`	VerifyFlags
`tx`	TX
`i`	Number

Source:

bcoin/script.js, line 3862

clone() → {Script}

Clone the script.

Source:

bcoin/script.js, line 892

Returns:

Cloned script.

Type: Script

concat(scripts) → {Array}

Concatenate scripts, inserting code separators in between them.

Parameters:

Name	Type	Description
`scripts`	Array.<Script>

Source:

bcoin/script.js, line 2128

Returns:

code

Type: Array

encode() → {Buffer}

Encode the script to a Buffer. Note that this will not contain the varint size before it. This allows it to be hashed for scripthashes.

Source:

bcoin/script.js, line 912

Returns:

Serialized script.

Type: Buffer

execute(stack, flagsnullable, txnullable, indexnullable, versionnullable) → {Boolean}

Execute the script and return false on script execution errors.

Parameters:

Name	Type	Attributes	Description
`stack`	Stack		Script execution stack.
`flags`	Number	<nullable>	Script standard flags.
`tx`	TX	<nullable>	Transaction being verified.
`index`	Number	<nullable>	Index of input being verified.
`version`	Number	<nullable>	Signature hash version (0=legacy, 1=segwit).

Source:

bcoin/script.js, line 966

Returns:

Whether the execution was successful.

Type: Boolean

getAddress() → {Base58Address|null}

Get the address of the script if present. Note that pubkey and multisig scripts will be treated as though they are pubkeyhash and scripthashes respectively.

Source:

bcoin/script.js, line 2431

Returns:

Type: Base58Address | null

getArgs() → {Number}

Calculate the number of expected "arguments" (pushdata ops in the input script) for an output script. Used for standardness verification.

Source:

bcoin/script.js, line 3505

Returns:

Type: Number

getCoinbaseData() → {Object}

Get info about a coinbase script.

Source:

bcoin/script.js, line 3079

Returns:

Object containing height, extraNonce, flags, and text.

Type: Object

getCoinbaseHeight() → {Number}

Get coinbase height.

Source:

bcoin/script.js, line 3036

Returns:

-1 if not present.

Type: Number

getCommitmentHash() → {Buffer|null}

Get the commitment hash if present.

Source:

bcoin/script.js, line 2669

Returns:

Type: Buffer | null

getHash() → {Hash|null}

Get the address hash of the script if present. Note that pubkey and multisig scripts will be treated as though they are pubkeyhash and scripthashes respectively.

Source:

bcoin/script.js, line 2493

Returns:

Type: Hash | null

getInputAddress() → {Base58Address|null}

"Guess" the address of the input script. This method is not 100% reliable.

Source:

bcoin/script.js, line 2392

Returns:

Type: Base58Address | null

getInputHash() → {Hash|null}

"Guess" the address hash of the input script. This method is not 100% reliable.

Source:

bcoin/script.js, line 2465

Returns:

Type: Hash | null

getInputType() → {String}

"Guess" the type of the input script. This method is not 100% reliable.

Source:

bcoin/script.js, line 2786

Returns:

Type: String

getRedeem() → {Script|null}

Grab and deserialize the redeem script.

Source:

bcoin/script.js, line 2251

Returns:

Redeem script.

Type: Script | null

getSigops(accurate) → {Number}

Count the sigops in the script.

Parameters:

Name	Type	Description
`accurate`	Boolean	Whether to enable accurate counting. This will take into account the `n` value for OP_CHECKMULTISIG(VERIFY).

Source:

bcoin/script.js, line 3469

Returns:

sigop count

Type: Number

getSize() → {Number}

Calculate size of script excluding the varint size bytes.

Source:

bcoin/script.js, line 2379

Returns:

Type: Number

getSmall(index) → {Number}

Get a small integer from an opcode (OP_0-OP_16).

Parameters:

Name	Type	Description
`index`	Number

Source:

bcoin/script.js, line 3657

Returns:

Type: Number

getSubscript(lastSepnullable) → {Script}

Get the script's "subscript" starting at a separator. Remove all OP_CODESEPARATORs if present. This bizarre behavior is necessary for signing and verification when code separators are present.

Parameters:

Name	Type	Attributes	Description
`lastSep`	Number	<nullable>	The last separator to sign/verify beyond.

Source:

bcoin/script.js, line 931

Returns:

Subscript.

Type: Script

getType() → {String}

Get the standard script type.

Source:

bcoin/script.js, line 2284

Returns:

Script script (can be any of 'witnesspubkeyhash', 'witnessscripthash', 'pubkey', 'multisig', 'scripthash', 'nulldata', or 'unknown').

Type: String

getWitnessProgram() → {Program|null}

Get the witness program if present.

Source:

bcoin/script.js, line 2728

Returns:

Type: Program | null

indexOf(data) → {Number}

Find a data element in a script.

Parameters:

Name	Type	Description
`data`	Buffer	Data element to match against.

Source:

bcoin/script.js, line 2020

Returns:

Index (-1 if not present).

Type: Number

inspect() → {String}

Inspect the script.

Source:

bcoin/script.js, line 901

Returns:

Human-readable script code.

Type: String

interpret(stack, flagsnullable, txnullable, indexnullable, versionnullable) → {Boolean}

Execute and interpret the script.

Parameters:

Name	Type	Attributes	Description
`stack`	Stack		Script execution stack.
`flags`	Number	<nullable>	Script standard flags.
`tx`	TX	<nullable>	Transaction being verified.
`index`	Number	<nullable>	Index of input being verified.
`version`	Number	<nullable>	Signature hash version (0=legacy, 1=segwit).

Source:

bcoin/script.js, line 991

Throws:

Will be thrown on VERIFY failures, among other things.
Type ScriptError

Returns:

Whether the execution was successful.

Type: Boolean

isCommitment() → {Boolean}

Test whether the output script is a segregated witness commitment. Note that commitments are a superset of nulldata as they can have multiple pushdata ops. When validating for standardness, commitments should not be allowed in anything but coinbases.

Source:

bcoin/script.js, line 2645

Returns:

Type: Boolean

isMultisig() → {Boolean}

Test whether the output script is pay-to-multisig.

Source:

bcoin/script.js, line 2546

Returns:

Type: Boolean

isMultisigInput() → {Boolean}

"Guess" whether the input script is pay-to-multisig. This method is not 100% reliable.

Source:

bcoin/script.js, line 2945

Returns:

Type: Boolean

isNulldata() → {Boolean}

Test whether the output script is nulldata/opreturn. This will fail if the pushdata is greater than 80 bytes.

Source:

bcoin/script.js, line 2610

Returns:

Type: Boolean

isPubkey() → {Boolean}

Test whether the output script is pay-to-pubkey.

Source:

bcoin/script.js, line 2521

Returns:

Type: Boolean

isPubkeyhash() → {Boolean}

Test whether the output script is pay-to-pubkeyhash.

Source:

bcoin/script.js, line 2532

Returns:

Type: Boolean

isPubkeyhashInput() → {Boolean}

"Guess" whether the input script is pay-to-pubkeyhash. This method is not 100% reliable.

Source:

bcoin/script.js, line 2929

Returns:

Type: Boolean

isPubkeyInput() → {Boolean}

"Guess" whether the input script is pay-to-pubkey. This method is not 100% reliable.

Source:

bcoin/script.js, line 2915

Returns:

Type: Boolean

isPushOnly() → {Boolean}

Test the script to see if it contains only push ops. Push ops are: OP_1NEGATE, OP_0-OP_16 and all PUSHDATAs.

Source:

bcoin/script.js, line 3447

Returns:

Type: Boolean

isScripthash() → {Boolean}

Test whether the output script is pay-to-scripthash. Note that bitcoin itself requires scripthashes to be in strict minimaldata encoding. Using OP_HASH160 OP_PUSHDATA1 [hash] OP_EQUAL will not be recognized as a scripthash.

Source:

bcoin/script.js, line 2590

Returns:

Type: Boolean

isScripthashInput() → {Boolean}

"Guess" whether the input script is pay-to-scripthash. This method is not 100% reliable.

Source:

bcoin/script.js, line 2982

Returns:

Type: Boolean

isStandard() → {Boolean}

Test whether the script is standard by policy standards.

Source:

bcoin/script.js, line 2315

Returns:

Type: Boolean

isStandardProgram() → {Boolean}

Test whether the program is standard (i.e. would it fail verification with non-mandatory flags).

Source:

bcoin/script.js, line 2339

Returns:

Type: Boolean

isUnknown() → {Boolean}

Test whether a script is of an unknown/non-standard type.

Source:

bcoin/script.js, line 2306

Returns:

Type: Boolean

isUnknownInput() → {Boolean}

"Guess" whether the input script is an unknown/non-standard type. This method is not 100% reliable.

Source:

bcoin/script.js, line 2814

Returns:

Type: Boolean

isWitnessProgram() → {Boolean}

Test whether the output script is a witness program. Note that this will return true even for malformed witness v0 programs.

Source:

bcoin/script.js, line 2683

Returns:

Type: Boolean

isWitnessPubkeyhash() → {Boolean}

Test whether the output script is a pay-to-witness-pubkeyhash script.

Source:

bcoin/script.js, line 2761

Returns:

Type: Boolean

isWitnessScripthash() → {Boolean}

Test whether the output script is a pay-to-witness-scripthash script.

Source:

bcoin/script.js, line 2773

Returns:

Type: Boolean

removeData(data) → {Number}

Remove all matched data elements from a script's code (used to remove signatures before verification). Note that this compares and removes data on the byte level. It also reserializes the data to a single script with minimaldata encoding beforehand. A signature will not be removed if it is not minimaldata.

Parameters:

Name	Type	Description
`data`	Buffer	Data element to match against.

Source:

bcoin/script.js, line 1939

See:

Returns:

Total.

Type: Number