Re: Adding support for SSLKEYLOGFILE in the frontend

Abhishek Chanda <abhishek.becs@gmail.com> writes:
> Attached is a patch to add support for logging secrets used in TLS
> connection after psql is initialized. This adds a new env var
> SSLKEYLOGFILE on the client side that points to a text file where keys
> will be logged.

I wonder if this poses a security risk, ie something forcing
extraction of TLS secrets at a distance via the environment variable.
I think it might be safer if we only accepted it as a connection
parameter and not via an environment variable.  (I'm aware of the
rule of thumb that if you control the environment then you own your
callees anyway, via modifying PATH and suchlike.  But there's a lot
of code that thinks it can sanitize the environment by overriding
PATH and other well-known variables.  Nobody is going to be aware
that SSLKEYLOGFILE is a security hazard.)

> 2. Should I use perror to report error here?

No.

> I did not want to use
> libpq_append_conn_error because this is not a connection related
> error.

Yes it is, IMO anyway.  Anything like this should be treated as a
libpq connection parameter.  The reason you couldn't find a place
to document this feature is you were ignoring libpq's conventions.

Just looking at the code itself, I'm a bit distressed that it's
not making any effort to secure the log file against prying eyes.
Shouldn't we be trying to create it with mode 0600?

			regards, tom lane