BIP: PSET
Layer: Applications
Title: Partially Signed Elements Transaction Format
Author: Andrew Chow
Comments-Summary: No comments yet.
Status: Proposed
Type: Standards Track
Created: 2020-07-09
License: BSD-2-Clause
==Introduction==
===Abstract===
This document describes proprietary extensions to the BIP 174 Partially Signed Bitcoin Transaction format.
These extensions are for use in Elements Sidechains to hold the information necessary for
Confidential Transactions, Confidential Assets, and Peg-in transactions.
===Copyright===
This BIP is licensed under the 2-clause BSD license.
==Specification==
The Partially Signed ELements Transaction (PSET) format is identical to the BIP 370 PSBT format.
The changes are new proprietary type fields, a new magic sequence, and new roles.
The fields added for PSET are only allowed when the PSBT version is 2.
For elements, the identifier prefix string is pset.
Note that previous implementations of PSET used a different prefix string and had different fields.
The use of a new identifier prefix is to avoid conflicts with the previous implementations.
The currently defined elements global proprietary types are as follows:
{|
! Name
!
!
! Description
!
! Description
! Versions Requiring Inclusion
! Versions Requiring Exclusion
! Versions Allowing Inclusion
|-
| Scalar Offset
| PSBT_ELEMENTS_GLOBAL_SCALAR = 0x00
| <32 byte scalar>
| A 32 byte Scalar Offset computed by a blinder.
| None
| No value. The value must have a length of zero.
|
| 0
| 2
|-
| Elements Transaction Modifiable Flag
| PSBT_ELEMENTS_GLOBAL_TX_MODIFIABLE = 0x01
| None
| No key data
| <8-bit uint>
| An 8 bit little endian unsigned integer as a bitfield for various elements specific transaction modification flags. Bit 0 is the PSBT Blinded flag and it is set to 1 to indicate that the PSET has not been blinded yet. Once all confidential values, rangeproofs, and asset surjection proofs have been attached to the PSET, it must be set to 0.
|
| 0
| 2
|}
The currently defined elements per-input proprietary types are as folows:
{|
! Name
!
!
! Description
!
! Description
! Versions Requiring Inclusion
! Versions Requiring Exclusion
! Versions Allowing Inclusion
|-
| Issuance Value
| PSBT_ELEMENTS_IN_ISSUANCE_VALUE = 0x00
| None
| No key data
| <64-bit int>
| The explicit little endian 64-bit integer for the value of this issuance. This is mutually exclusive with PSBT_ELEMENTS_IN_ISSUANCE_VALUE_COMMITMENT
|
| 0
| 2
|-
| Issuance Value Commitment
| PSBT_ELEMENTS_IN_ISSUANCE_VALUE_COMMITMENT = 0x01
| None
| No key data
| <33 byte commitment>
| The 33 byte Value Commitment. This is mutually exclusive with PSBT_IN_ISSUANCE_VALUE.
|
| 0
| 2
|-
| Issuance Value Rangeproof
| PSBT_ELEMENTS_IN_ISSUANCE_VALUE_RANGEPROOF = 0x02
| None
| No key data
|
| The rangeproof
|
| 0
| 2
|-
| Issuance Inflation Keys Rangeproof
| PSBT_ELEMENTS_IN_ISSUANCE_KEYS_RANGEPROOF = 0x03
| None
| No key data
|
| The rangeproof
|
| 0
| 2
|-
| Peg-in Transaction
| PSBT_ELEMENTS_IN_PEG_IN_TX = 0x04
| None
| No key data
|
| The Peg-in Transaction serialized without witnesses.
|
| 0
| 2
|-
| Peg-in Transaction Output Proof
| PSBT_ELEMENTS_IN_PEG_IN_TXOUT_PROOF = 0x05
| None
| No key data
|
| The transaction output proof for the Peg-in Transaction.
|
| 0
| 2
|-
| Peg-in Genesis Hash
| PSBT_ELEMENTS_IN_PEG_IN_GENESIS = 0x06
| None
| No key data
|
| The 32 byte genesis hash for the Peg-in Transaction.
|
| 0
| 2
|-
| Peg-in Claim Script
| PSBT_ELEMENTS_IN_PEG_IN_CLAIM_SCRIPT = 0x07
| None
| No key data
|