From e0d51f1035d37f3b7db303fb0b431bbd33ccbde7 Mon Sep 17 00:00:00 2001 From: Ferdinando Ametrano Date: Wed, 5 Aug 2026 23:52:39 +0200 Subject: [PATCH] BIP-174: test data: a public key in the witnessScript case The "PSBT with invalid output witnessScript typed key" case tests one condition: a PSBT_OUT_WITNESS_SCRIPT key longer than the one octet the type is. Its last record, key length included, is 21 010025512103b7ce...51309d 06 d57f8a8751ae Read as a stream, the witnessScript is OP_1 <03b7ce23...51309d06d57f8a87> OP_1 OP_CHECKMULTISIG and x^3 + 7 is not a square mod p for that x: the pushed key is not a point of secp256k1. An implementation that checks the pushed key but not the key length refuses the case for the wrong reason and the missing check goes undetected. 65f0b3dd62ec replaced 2b with 06 to make the value length consistent: with 2b it is 43 where 7 octets remain, and a reader that takes the whole key-value pair before judging the key hits a short read. That octet is the 29th of the pushed key. The case commits to the key with 2b. sha256 of that script is 876bad83...2b278a65, the P2WSH the output's redeemScript pushes, and hash160 of that redeemScript is b921b1ba...6a42ec83, the P2SH scriptPubKey of the unsigned transaction's second output. The script as it reads today hashes to bcea4f01...fbb21dc8, which nothing in the case commits to. Another point in its place would mean recomputing both hashes and the unsigned transaction; keeping it means moving the value length off it. The record below does that, carrying the extra octet in the key and the whole script in the value, as the "invalid output redeemScript typed key" case does. 02 0100 25 512103b7ce...2bd57f8a8751ae Same length as now, same failure, and the first 222 of the 264 octets unchanged. --- bip-0174.mediawiki | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/bip-0174.mediawiki b/bip-0174.mediawiki index 454a1db5fa..640a20711d 100644 --- a/bip-0174.mediawiki +++ b/bip-0174.mediawiki @@ -679,8 +679,8 @@ The following are invalid PSBTs: ** Base64 String: 
cHNidP8BAHMCAAAAATAa6YblFqHsisW0vGVz0y+DtGXiOtdhZ9aLOOcwtNvbAAAAAAD/////AnR7AQAAAAAAF6kUA6oXrogrXQ1Usl1jEE5P/s57nqKHYEOZOwAAAAAXqRS5IbG6b3IuS/qDtlV6MTmYakLsg4cAAAAAAAEBHwDKmjsAAAAAFgAU0tlLZK4IWH7vyO6xh8YB6Tn5A3wAAgAAFgAUYunpgv/zTdgjlhAxawkM0qO3R8sAAQAiACCHa62DLx0WgBXtQSMqnqZaGBXZ7xPA74dZ9ktbKyeKZQEBJVEhA7fOI6AcW0vwCmQlN836uzFbZoMyhnR471EwnSvVf4qHUa4A
* Case: PSBT with invalid output witnessScript typed key -** Bytes in Hex: 
70736274ff0100730200000001301ae986e516a1ec8ac5b4bc6573d32f83b465e23ad76167d68b38e730b4dbdb0000000000ffffffff02747b01000000000017a91403aa17ae882b5d0d54b25d63104e4ffece7b9ea2876043993b0000000017a914b921b1ba6f722e4bfa83b6557a3139986a42ec8387000000000001011f00ca9a3b00000000160014d2d94b64ae08587eefc8eeb187c601e939f9037c00010016001462e9e982fff34dd8239610316b090cd2a3b747cb000100220020876bad832f1d168015ed41232a9ea65a1815d9ef13c0ef8759f64b5b2b278a6521010025512103b7ce23a01c5b4bf00a642537cdfabb315b668332867478ef51309d06d57f8a8751ae00
-** Base64 String: 
cHNidP8BAHMCAAAAATAa6YblFqHsisW0vGVz0y+DtGXiOtdhZ9aLOOcwtNvbAAAAAAD/////AnR7AQAAAAAAF6kUA6oXrogrXQ1Usl1jEE5P/s57nqKHYEOZOwAAAAAXqRS5IbG6b3IuS/qDtlV6MTmYakLsg4cAAAAAAAEBHwDKmjsAAAAAFgAU0tlLZK4IWH7vyO6xh8YB6Tn5A3wAAQAWABRi6emC//NN2COWEDFrCQzSo7dHywABACIAIIdrrYMvHRaAFe1BIyqeploYFdnvE8Dvh1n2S1srJ4plIQEAJVEhA7fOI6AcW0vwCmQlN836uzFbZoMyhnR471EwnQbVf4qHUa4A
+** Bytes in Hex: 
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
+** Base64 String: 
cHNidP8BAHMCAAAAATAa6YblFqHsisW0vGVz0y+DtGXiOtdhZ9aLOOcwtNvbAAAAAAD/////AnR7AQAAAAAAF6kUA6oXrogrXQ1Usl1jEE5P/s57nqKHYEOZOwAAAAAXqRS5IbG6b3IuS/qDtlV6MTmYakLsg4cAAAAAAAEBHwDKmjsAAAAAFgAU0tlLZK4IWH7vyO6xh8YB6Tn5A3wAAQAWABRi6emC//NN2COWEDFrCQzSo7dHywABACIAIIdrrYMvHRaAFe1BIyqeploYFdnvE8Dvh1n2S1srJ4plAgEAJVEhA7fOI6AcW0vwCmQlN836uzFbZoMyhnR471EwnSvVf4qHUa4A
* Case: PSBT with unsigned tx serialized with witness serialization format ** Bytes in Hex: 
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