BIPs bitcoin improvement proposals

raw() and addr() Output Script Descriptors

  BIP: 385 source
  Layer: Applications
  Title: raw() and addr() Output Script Descriptors
  Author: Pieter Wuille <pieter@wuille.net>
          Ava Chow <me@achow101.com>
  Comments-Summary: No comments yet.
  Comments-URI: https://github.com/bitcoin/bips/wiki/Comments:BIP-0385
  Status: Final
  Type: Informational
  Created: 2021-06-27
  License: BSD-2-Clause

Table of Contents

Abstract

This document specifies raw() and addr() output script descriptors. raw() encapsulates a raw script as a descriptor. addr() encapsulates an address as a descriptor.

Copyright

This BIP is licensed under the BSD 2-clause license.

Motivation

In order to make descriptors maximally compatible with scripts in use today, it is useful to be able to wrap any arbitrary output script or an address into a descriptor.

Specification

Two new script expressions are defined: raw() and addr().

raw()

The raw(HEX) expression can only be used as a top level descriptor. As the argument, it takes a hex string representing a Bitcoin script. The output script produced by this descriptor is the script represented by HEX.

addr()

The addr(ADDR) expression can only be used as a top level descriptor. It takes an address as its single argument. The output script produced by this descriptor is the output script produced by the address ADDR.

Test Vectors

Valid descriptors followed by the scripts they produce.

  • raw(deadbeef)
    • deadbeef
  • raw(512103a34b99f22c790c4e36b2b3c2c35a36db06226e41c692fc82b8b56ac1c540c5bd4104a34b99f22c790c4e36b2b3c2c35a36db06226e41c692fc82b8b56ac1c540c5bd5b8dec5235a0fa8722476c7709c02559e3aa73aa03918ba2d492eea75abea23552ae)
    • 512103a34b99f22c790c4e36b2b3c2c35a36db06226e41c692fc82b8b56ac1c540c5bd4104a34b99f22c790c4e36b2b3c2c35a36db06226e41c692fc82b8b56ac1c540c5bd5b8dec5235a0fa8722476c7709c02559e3aa73aa03918ba2d492eea75abea23552ae
  • raw(a9149a4d9901d6af519b2a23d4a2f51650fcba87ce7b87)
    • a9149a4d9901d6af519b2a23d4a2f51650fcba87ce7b87
  • addr(3PUNyaW7M55oKWJ3kDukwk9bsKvryra15j)
    • a914eeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee87
Invalid descriptors

  • Non-hex script: raw(asdf)
  • Invalid address: addr(asdf)
  • raw nested in sh: sh(raw(deadbeef))
  • raw nested in wsh: wsh(raw(deadbeef))
  • addr nested in sh: sh(addr(3PUNyaW7M55oKWJ3kDukwk9bsKvryra15j))
  • addr nested in wsh: wsh(addr(3PUNyaW7M55oKWJ3kDukwk9bsKvryra15j))

Backwards Compatibility

raw() and addr() descriptors use the format and general operation specified in 380. As this is a wholly new descriptor, it is not compatible with any implementation. The reuse of existing Bitcoin addresses allows for this to be more easily implemented.

Reference Implementation

raw() and addr() descriptors have been implemented in Bitcoin Core since version 0.17.