Re: Large object security

The problem with this is that the existing functionality of LOs allows
you to share a single LO across multiple tables. There may not be a
single source, but multiple. Since LOs just use an OID as a FK to the
LO, you can store that OID in multiple different tables.

--Barry

Mario Weilguni wrote:
> would'nt it be much better to expand pg_largeobject to have another column "src_oid" (or similar), containing the OID of the referencing table from pg_class, and when accessing large objects take the privilieges from the referencing class?
>
> -----Ursprüngliche Nachricht-----
> Von: Damon Cokenias [mailto:lists(at)mtn-palace(dot)com]
> Gesendet: Freitag, 19. April 2002 11:04
> An: pgsql-hackers
> Betreff: [HACKERS] Large object security
>
>
> Hi all,
>
> I see there's a TODO item for large object security, it's a feature I'd really like to see. I'm willing to put in the time to write a patch, but know far to little about postgres internals and history to just dive in. Has there been any discussion on this list about what this feature should be or how it might be implemented? I saw a passing reference to "LOB LOCATORs" in the list archives, but that was all.
>
> What's a LOB LOCATOR ?
>
> What about giving each large object its own permission flags? ex:
>
> GRANT SELECT ON LARGE OBJECT 10291 TO USER webapp;
> GRANT SELECT, DELETE, UPDATE ON LARGE OBJECT 10291 TO USER admin;
>
> Default permission flags (and INSERT permissions) would be set at the table level. All objects without specific permissions would use the table rules. This allows for backward compatibility and convenience.
>
> I think per-object security is important. A user shouldn't be able to get at another user's data just by guessing the right OID. Ideally, users without permission would not know there were objects in the database they were not allowed to see.
>
> I can also imagine a security scheme that uses rule/trigger syntax to give the user a hook to provide her own security functions. I haven't thought that through, though.
>
> Any thoughts?
>
>
> -Damon
>
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