On Mon, 23 Mar 2009 01:07:18 -0600 Scott Marlowe <scott.marl...@gmail.com> wrote:
> On Mon, Mar 23, 2009 at 12:59 AM, Stephen Cook <scli...@gmail.com> > wrote: > > You should use pg_query_params() rather than build a SQL > > statement in your code, to prevent SQL injection attacks. Also, > > if you are going to read this data back out and show it on a web > > page you probably should make sure there is no rogue HTML or > > JavaScript or anything in there with htmlentities() or somesuch. > > Are you saying pg_quer_params is MORE effective than > pg_escape_string at deflecting SQL injection attacks? I didn't follow the thread from the beginning but I'd say yes. It should avoid queueing multiple statements and it is a more "general" method that let you pass parameters in one shot in spite of building the string a bit at a time for every parameter you insert (string, float, integer...). Of course if you correctly escape/cast/whatever everything injecting 2 statements shouldn't be possible... but if you don't you give more freedom to the attacker. $sql='select * from '.$table.' where a=$1 and $b=$2'; //oops I made a mistake. $result=db_query_params($sql,array(1,'bonzo')); If $table is external input and an attacker pass existingtable; delete from othertable; -- The attack may just result in a DOS if existingtable is there but your othertable shouldn't be wiped. untested... but I recall pg_query and pg_query_params use different C calls PGexec vs. PGexecParams and the later "Unlike PQexec, PQexecParams allows at most one SQL command in the given string." http://www.postgresql.org/docs/8.3/interactive/libpq-exec.html I think pg_query_params should make a difference between floats and integers and signal an error if you pass float where integers are expected... but I'm not sure. Not really a security concern, but an early warning for some mistake. -- Ivan Sergio Borgonovo http://www.webthatworks.it -- Sent via pgsql-general mailing list (pgsql-general@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
