From: William Casarin <jb55@jb55.com>
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	Bitcoin Protocol Discussion <bitcoin-dev@lists.linuxfoundation.org>
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Date: Tue, 26 Jun 2018 23:09:09 -0700
Message-ID: <87k1qk7oca.fsf@jb55.com>
MIME-Version: 1.0
Content-Type: text/plain
Subject: Re: [bitcoin-dev] BIP 174 thoughts
Precedence: list


Hey Andrew,

If I'm reading the spec right: the way it is designed right now, you
could create hundreds of thousands of zero bytes in the input or output
key-value arrays. As far as I can tell this would be considered valid,
as it is simply a large array of empty dictionaries. Is this right? I'm
worried about buffer overflows in cases where someone sends a large blob
of zeros to an unsuspecting implementation.


Also, the extensibility section reads:

> Additional key-value maps with different types for the key-value pairs
> can be added on to the end of the format.

"different types for the key-value pairs", is this referring to new
types beyond the current global, input and output types?

> The number of each map that follows must be specified in the globals
> section

Is this out of date? Since there is only one type in the global section
now (tx).

> so that parsers will know when to use different definitions of the
> data types

I'm not sure what this means.


Thanks!

Will


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