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Date: Mon, 03 Feb 2025 13:38:04 +0700
From: Vladlen Popolitov <v.popolitov@postgrespro.ru>
To: Sutou Kouhei <kou@clear-code.com>
Cc: sawada.mshk@gmail.com, zhjwpku@gmail.com, michael@paquier.xyz,
 pgsql-hackers@postgresql.org
Subject: Re: Make COPY format extendable: Extract COPY TO format
 implementations
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Sutou Kouhei писал(а) 2025-02-01 17:12:
> Hi,
> 

Hi
I would like to inform about the security breach in your design of COPY 
TO/FROM.

You use FORMAT option to add new formats, filling it with routine name
in shared library. As result any caller can call any routine in 
PostgreSQL kernel.
I think, it will start competition, who can find most dangerous routine
to call just from COPY FROM command.

  Standard PostgreSQL realisation for new methods to use USING keyword. 
Every
new method could have own options (FORMAT is option of internal 'copy 
from/to'
methods), it assumes some SetOptions interface, that defines
an options structure according to the new method requirements.

  I agree with the general direction of the extensibility, but it should 
be secure
and consistent.

-- 
Best regards,

Vladlen Popolitov.