× The internal search function is temporarily non-functional. The current search engine is no longer viable and we are researching alternatives.
As a stop gap measure, we are using Google's custom search engine service.
If you know of an easy to use, open source, search engine ... please contact support@midrange.com.


  1.  Home
  2. RPG400-L
  3. August 2011

Re: Reduce large amount of logicals in SUBFL pgm, take in another direction

Gary,

I have been known to disagree with Charles on assorted matters, but on this
one, he's absolutely correct.

If you have code somewhere in your application which directly concatenates
strings to form an SQL statement and one of those strings comes directly
from the user, you may be at risk of SQL injection (depending on the
specific strings). It doesn't matter whether this is in a top-level program
or some code in a module that's bound into a service program way deep in
your application.

As has been pointed out, you can mitigate/avoid this, by either using
parameters or by manually 'cleaning' the user-provided string yourself.

Rory

On Mon, Aug 1, 2011 at 11:25 AM, Monnier, Gary <Gary.Monnier@xxxxxxxxx>wrote:

Charles,

So we choose to disagree.

Gary


-----Original Message-----
From: rpg400-l-bounces+gary.monnier=terex.com@xxxxxxxxxxxx [mailto:
rpg400-l-bounces+gary.monnier=terex.com@xxxxxxxxxxxx] On Behalf Of Charles
Wilt
Sent: Monday, August 01, 2011 11:19 AM
To: RPG programming on the IBM i / System i
Subject: Re: Reduce large amount of logicals in SUBFL pgm,take in another
direction

Gary,

You seem to be hung up on *MODULE...

I repeat, it doesn't matter where the statement is built. If you're
building a statement dynamically with concatenation of user supplied string.
The code is vulnerable. It doesn't have anything to do with *PGM, *MODULE,
*SRVPGM, authority or debug mode.

Charles

On Mon, Aug 1, 2011 at 1:54 PM, Monnier, Gary <Gary.Monnier@xxxxxxxxx>
wrote:
Charles,

With respect you seem to be hung up on my example being a *PGM. I
recommended *MODULE. If you feel someone can get to a *PGM build from
*MODULEs and can inject an SQL statement then again I assert security
settings to the program are set incorrectly. Either you allow *PUBLIC to
debug the program or you have had a security breach involving a profile with
enough authority to debug the program. If the executable *PGM allows
modules and or service programs to be changed then you also have a security
hole. In both cases it is not my example causing the breach and other much
larger security issues are in play.

Respectfully,

Gary Monnier


-----Original Message-----
From: rpg400-l-bounces@xxxxxxxxxxxx
[mailto:rpg400-l-bounces@xxxxxxxxxxxx] On Behalf Of Charles Wilt
Sent: Monday, August 01, 2011 6:06 AM
To: RPG programming on the IBM i / System i
Subject: Re: Reduce large amount of logicals in SUBFL pgm,take in
another direction

Gary,

If you think that your program doesn't open you up to SQL injection, you
are sadly mistaken...

The fact that the procedure is bound statically by reference or by copy
as opposed to a dynamic called *PGM has no bearing.

SQL injection attacks can occur anytime you dynamically build a statement
and concatenate user string input into the statement. It doesn't matter
where the statement is built.

Again, all that matters is that in some way shape or form, you are
building a statement like so:
wSqlStmt = 'SELECT * FROM MYTABLE WHERE MYFLD = ' + userEnteredValue;

Theoretically, you could parse and sanitize the user input, making
sure it's safe before using it. However, unlike some languages RPG
doesn't have that functionality built in. Also, IMHO you're dependent
on the guy who wrote the sanitizer being smarter than the hackers :)

The safe way to do dynamic statements is via parameter markers. You
build a statement like so:
wSqlStmt = 'SELECT * FROM MYTABLE WHERE MYFLD = ?';

then when you open/execute it, you pass in the variables to use at the
parameter markers.
open C1 using :userEnteredValue;

With respect to PCI requirements...
6.5 Develop applications based on secure coding guidelines and review
custom application code to identify coding vulnerabilities. Follow
up-to-date industry best practices to identify and manage vulnerabilities.

OWASP is one of the standards usually used for secure coding...their top
security risk for 2010...injection (SQL queries, LDAP queries, XPath
queries, OS commands, program arguments, etc. ).
https://www.owasp.org/index.php/Category:OWASP_Top_Ten_Project

Thus, dynamic SQL as used by your programs would fail an secure code
review and you'd likely fail a PCI audit.

HTH,
Charles






On Fri, Jul 29, 2011 at 2:26 PM, Monnier, Gary <Gary.Monnier@xxxxxxxxx>
wrote:
Your opinion Charles and what seems a very strong opinion. J



Yes, I've heard of SQL Injection attacks and no my suggestion does
not leave you open to this sort of attack. I've also heard of LDAP
injection attacks.



What I suggested does not impact PCI compliance or any other security
parameters. Nor does it impact FDA compliance. All the MODULE does
is build an SQL string. When bound with other modules to make an
executable object there are no compliance issues.



If you create ILE programs that allow updating modules or service
programs then you have a behavior that needs changing. My opinion
is, and it is only my opinion, you should NEVER create a program with
Allow update. You are just asking for trouble in the ILE world.



If you have ulcer causing issues with pgmToBuildSQL make it a copy
module rather than a bound module.



Regards,



Gary





-----Original Message-----
From: rpg400-l-bounces@xxxxxxxxxxxx
[mailto:rpg400-l-bounces@xxxxxxxxxxxx] On Behalf Of Charles Wilt
Sent: Friday, July 29, 2011 10:35 AM
To: RPG programming on the IBM i / System i
Subject: Re: Reduce large amount of logicals in SUBFL pgm,take in
another direction



Very, very BAD IDEA!



Horrible in fact.



I hope you're not subject to PCI compliance rules, as the code you
posted pretty much guarantees an automatic failure.



Try googleing for "SQL injection"...



Charles



On Fri, Jul 29, 2011 at 1:16 PM, Monnier, Gary
<Gary.Monnier@xxxxxxxxx <mailto:Gary.Monnier@xxxxxxxxx> > wrote:

Sharon,



The process that builds your SQL statement can have parameters
passed

to it. One of these parameters can be a list of selections.

Something like this.



pgmToBuildSQL PR

nbrFieldsForWhereClause

arrayOfFieldsForWhereClause

arrayOfValuesForWhereClause





SQLStringBegin = 'Select * From yourfile ';



X = 1;

startPos = 1;



doW (X < = nbrFieldsForWhereClause);



whereValue = arrayOfFieldsForWhereClause(X) +

arrayOfValuesForWhereClause(X); //ValueFor can be = value, like

value, etc

valueLen = %len(%trimr(whereValue));

%subst(whereClause:startPos:valueLen) = whereValue;

startpos = startPos + valueLen + 1;

X = X + 1;



enddo;



Return;



--

This is the RPG programming on the IBM i / System i (RPG400-L)
mailing list To post a message email: RPG400-L@xxxxxxxxxxxx
<mailto:RPG400-L@xxxxxxxxxxxx> To subscribe, unsubscribe, or change
list options,

visit: http://lists.midrange.com/mailman/listinfo/rpg400-l
<http://lists.midrange.com/mailman/listinfo/rpg400-l>

or email: RPG400-L-request@xxxxxxxxxxxx
<mailto:RPG400-L-request@xxxxxxxxxxxx>

Before posting, please take a moment to review the archives at
http://archive.midrange.com/rpg400-l
<http://archive.midrange.com/rpg400-l> .



--
This is the RPG programming on the IBM i / System i (RPG400-L)
mailing list To post a message email: RPG400-L@xxxxxxxxxxxx To
subscribe, unsubscribe, or change list options,
visit: http://lists.midrange.com/mailman/listinfo/rpg400-l
or email: RPG400-L-request@xxxxxxxxxxxx Before posting, please take a
moment to review the archives at http://archive.midrange.com/rpg400-l.


--
This is the RPG programming on the IBM i / System i (RPG400-L) mailing
list To post a message email: RPG400-L@xxxxxxxxxxxx To subscribe,
unsubscribe, or change list options,
visit: http://lists.midrange.com/mailman/listinfo/rpg400-l
or email: RPG400-L-request@xxxxxxxxxxxx Before posting, please take a
moment to review the archives at http://archive.midrange.com/rpg400-l.

--
This is the RPG programming on the IBM i / System i (RPG400-L) mailing
list To post a message email: RPG400-L@xxxxxxxxxxxx To subscribe,
unsubscribe, or change list options,
visit: http://lists.midrange.com/mailman/listinfo/rpg400-l
or email: RPG400-L-request@xxxxxxxxxxxx Before posting, please take a
moment to review the archives at http://archive.midrange.com/rpg400-l.


--
This is the RPG programming on the IBM i / System i (RPG400-L) mailing list
To post a message email: RPG400-L@xxxxxxxxxxxx To subscribe, unsubscribe,
or change list options,
visit: http://lists.midrange.com/mailman/listinfo/rpg400-l
or email: RPG400-L-request@xxxxxxxxxxxx
Before posting, please take a moment to review the archives at
http://archive.midrange.com/rpg400-l.

--
This is the RPG programming on the IBM i / System i (RPG400-L) mailing list
To post a message email: RPG400-L@xxxxxxxxxxxx
To subscribe, unsubscribe, or change list options,
visit: http://lists.midrange.com/mailman/listinfo/rpg400-l
or email: RPG400-L-request@xxxxxxxxxxxx
Before posting, please take a moment to review the archives
at http://archive.midrange.com/rpg400-l.





As an Amazon Associate we earn from qualifying purchases.

This thread ...
Follow-Ups:
Replies:
Follow On AppleNews
Return to Archive home page | Return to MIDRANGE.COM home page

This mailing list archive is Copyright 1997-2024 by midrange.com and David Gibbs as a compilation work. Use of the archive is restricted to research of a business or technical nature. Any other uses are prohibited. Full details are available on our policy page. If you have questions about this, please contact [javascript protected email address].

Operating expenses for this site are earned using the Amazon Associate program and Google Adsense.