Re: Proposal: BSD Authentication support

>Our usual wording is "the PostgreSQL user account". Perhaps we should
>be more explicit about the fact that membership of this Unix group is
>needed on *OpenBSD*, since other current or future BSD forks could
>vary. I see that the specific reason this is needed on this OpenBSD
>5.8 box is so that it can fork/exec the setuid login_XXX binaries that
>live under /usr/libexec/auth.

The BSD Authentication framework currently only exists on OpenBSD. I've added some explicit documentation that this
mechanismis currently only supported on OpenBSD and I've tried to be a bit more explicit about the auth group as
suggestedby Peter. 

>auth_userokay is called with a type of "pg-auth". I noticed from
>looking at man page and source of some other applications that the
>convention is usually a hardcoded string like "auth-myserver",
>"auth-sockd", "auth-ssh", "auth-doas", "auth-popa3d" etc. So perhaps
>we should have "auth-postgresql" (or "auth-postgres" or "auth-pgsql")
>here? And as Peter E already said, that string should probably be
>documented: it looks a bit like it is useful for allowing the
>available authentication styles to be restricted or defaulted
>specifically for PostgreSQL in login.conf based on that string.
>(Though when I tried to set that up, it seemed to ignore my
>possibly-incorrectly-specified rule asking it to use "reject" so I may
>have misunderstood.)

This is correct, although so far I've only tested using the default login class. The attached patch includes some more
explicitdocumentation about this string.  

>The style argument is hard coded as NULL, as I see is the case in some
>other applications. From the man page: "If style is not NULL, it
>specifies the desired style of authentication to be used. If it is
>NULL then the default style for the user is used. In this case, name
>may include the desired style by appending it to the user's name with
>a single colon (‘:’) as a separator." I wonder if such
>user-controllable styles are OK (though I guess would require username
>mapping to strip them off if we do want that as a feature). I wonder
>if it should be possible to provide the style argument that we pass to
>auth_userokay explicitly in pg_hba.conf, so that the DBA could
>explicitly say BSD auth with style=radius.

I've so far only tested passwd authentication. I'd be interested to test some of the other authentication styles, I
thinkthis would be a useful feature.