Thread: to_tsquery, plainto_... avoiding bad input, injections. Is there a builtin function for this ? Escaping?

Hi, I am wondering whether or not there exists any built in function for making sure a query/textinput is not harmful or one that escapes them. If not, what kind of things should I watch out for ?

..... any one?

Maybe I'm missing the point, but have read about quote_ident() and
quote_literal() at chapter 9.4 "String Functions and Operators"?

BR

--
Fahrbahn ist ein graues Band
weisse Streifen, grüner Rand

On Thursday 08 January 2009 09:52:29 Mohamed wrote:
> ..... any one?
>
> On Wed, Jan 7, 2009 at 8:07 PM, Mohamed <mohamed5432154321@gmail.com> wrote:
> > Hi, I am wondering whether or not there exists any built in function for
> > making sure a query/textinput is not harmful or one that escapes them. If
> > not, what kind of things should I watch out for ?
> > As of now, I get errors on the quote ( ' ) if it is entered in an input
> > and in to_tsquery also on space. What other tokens should I be careful
> > about? How should I handle these ? How do I escape them ?
> >
> > When fulltext indexing my text, is there any risk that the text being
> > indexed could be harmful if it contains certain characters ?
> >
> > / Moe

Greetings!

> Wed, Jan 7, 2009 at 8:07 PM, Mohamed <mohamed5432154321@gmail.com>
> > Hi, I am wondering whether or not there exists any built in
> > function for making sure a query/textinput is not harmful or one
> > that escapes them. If not, what kind of things should I watch out
> > for ?
>
> * Reg Me Please <regmeplease@gmail.com> [2009-Jan-08 00:20 AKST]:
> Maybe I'm missing the point, but have read about quote_ident() and
> quote_literal() at chapter 9.4 "String Functions and Operators"?

quote_literal() does seem like a good choice for getting the quoting
correct.  As far as protecting yourself from SQL injection attacks, you
may want to look at the options available in the programming language
you are using to get user input.  In Python, for example, you can run
queries as follows:

  parameters = (12, "bar", True)
  query = "INSERT INTO foo VALUES (%d, %s, %s);"
  cursor.execute(query, parameters)
  cursor.commit()

Python fills the '%X' fields with the parameters after verifying they
are safe.  Probably best to test how much protection this offers.

I believe the risk isn't so much a question of quoting or special
characters, but carefully crafted input variables.  For example, what if
the second parameter was:

  "'bar', True); DELETE FROM foo; INSERT INTO foo VALUES (1, 'bar',"

Cheers,

Chris
--
Christopher S. Swingley
http://swingleydev.com/
<cswingle@gmail.com>

Yeah, would Python protect you from that ? I am using Groovy on Grails and not sure how these things work here. Most of the time I use GORM to do my queries, but now I am stuck with SQL because of fulltext search with Postgres. Perhaps there is some similiar things in Groovy to run, I will check into that.