To: bitcoin-dev@lists.linuxfoundation.org
From: Andreas Schildbach <andreas@schildbach.de>
Date: Fri, 13 Apr 2018 17:32:15 +0200
Message-ID: <paqids$e14$1@blaine.gmane.org>
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Subject: [bitcoin-dev] BloomFilter issue with segwit addresses
Precedence: list

Anton, a developer on the bitcoinj maiing list, recently made me aware
[1] of a compatibility issue between segwit and BIP37 (Bloom Filtering).

The issue affects only P2WPKH and the special case of transactions
without change outputs (such as when emptying a wallet). In this case,
neither inputs not outputs contain any data elements that would cause a
match for the filter. The public key, which would match, goes to the
witness but not to the input.

My suggestion was to include an OP_RETURN output with a matching public
key in such transactions. Anton confirmed that this workaround is indeed
working. But of course it nullifies some of the segwit's size improvements.

I wonder if Bitcoin Core would be willing to extend the BIP37 matching
rules such that data elements in the witness are also matched against?


[1] https://groups.google.com/d/msg/bitcoinj/SJpLgjowc1I/V7u2BavvAwAJ