TYPE 0x0905 · LEGACY FAMILY

P2WSH_LEGACY

Legacy P2WSH (pay-to-witness-script-hash) wrapped as a typed Ladder Script block. SHA256 of inner conditions must match. Same pattern as P2SH but with SHA256.

Legacy Invertible

Ladder Diagram

Fields

Field	Data Type	Size	Side	Description
hash256	HASH256	32 B	Conditions	SHA256 commitment to the inner script. Node-computed — the user provides PREIMAGE (serialised Ladder Script conditions) and the node computes this field automatically. Raw hash input is rejected.
preimage	PREIMAGE	var	Witness	Serialised Ladder Script conditions (the inner script) — provided by the user. The node derives HASH256 from this data at creation time.
[inner witness]	var	var	Witness	Witness fields required to satisfy the inner conditions

Wire Format Breakdown

Conditions side (in scriptPubKey):

0x0905 0 1 HASH256 · 32B = 38 bytes

Witness side (in input witness):

0x0905 0 n PREIMAGE · varB [inner witness fields] = variable

Total (conditions + witness) variable

Witness size depends on the inner Ladder Script conditions and their witness fields.

Evaluation Logic

1. Compute SHA256(PREIMAGE).

2. Compare computed hash to committed HASH256. If mismatch → UNSATISFIED

3. Deserialize PREIMAGE as Ladder Script conditions. If invalid → UNSATISFIED

4. Evaluate inner conditions with remaining witness fields. Result → SATISFIED or UNSATISFIED

Return Values

Condition	Result
Missing HASH256 or PREIMAGE	ERROR
HASH256 wrong size (not 32B)	ERROR
SHA256(PREIMAGE) != committed hash	UNSATISFIED
PREIMAGE fails to deserialize as Ladder conditions	ERROR
Inner conditions evaluation fails	UNSATISFIED
Recursion depth > 2	ERROR
Inner conditions satisfied	SATISFIED

JSON Wire Format

Conditions (scriptPubKey)

{
  "type": "P2WSH_LEGACY",
  "inverted": false,
  "fields": [
    { "type": "HASH256", "hex": "e3b0c4...32 bytes" }
  ]
}

Witness (input)

{
  "type": "P2WSH_LEGACY",
  "inverted": false,
  "fields": [
    { "type": "PREIMAGE", "hex": "01020304...serialised Ladder conditions" },
    { "type": "PUBKEY", "hex": "02abc1...33 bytes" },
    { "type": "SIGNATURE", "hex": "e5f6a7...64 bytes" }
  ]
}

Notes

Same anti-spam properties as P2SH_LEGACY — inner script must be valid Ladder Script.
The HASH256 field is node-computed: the user supplies PREIMAGE (the inner script) and the node derives the hash commitment automatically. Submitting a raw HASH256 value directly is rejected.
Uses SHA256 instead of HASH160 for the script hash, matching Bitcoin's P2WSH design.
Recursion depth limited to 2.

Use Cases

Segwit Script Migration

Same anti-spam pattern as P2SH_LEGACY but using SHA256 hash (matching P2WSH).

Complex Inner Conditions

Inner Ladder conditions with full composability, behind a SHA256 commitment.

← P2WPKH_LEGACY P2TR_LEGACY →