LISTSERV mailing list manager LISTSERV 16.0

Help for ZNG Archives


ZNG Archives

ZNG Archives


ZNG@C4VLPLISTSERV01.LOC.GOV


View:

Message:

[

First

|

Previous

|

Next

|

Last

]

By Topic:

[

First

|

Previous

|

Next

|

Last

]

By Author:

[

First

|

Previous

|

Next

|

Last

]

Font:

Proportional Font

LISTSERV Archives

LISTSERV Archives

ZNG Home

ZNG Home

ZNG  June 2002

ZNG June 2002

Subject:

Re: result set model for srw

From:

Matthew Dovey <[log in to unmask]>

Reply-To:

Z39.50 Next-Generation Initiative

Date:

Fri, 14 Jun 2002 12:50:31 +0100

Content-Type:

text/plain

Parts/Attachments:

Parts/Attachments

text/plain (88 lines)

> Theo, paraphrased:
> > You just need the request parameters.
> 
> No.  This would work if resultsets only last for one 
> response/request. However if I were to do a search, do a 
> second search and then try to combine the resultsets from 
> those two searches, the first would have already disappeared.

Who so? - neither result set should disappear unless there TTL values
have expired. If the TTL hasn't expired the server cannot delete them.
If the TTL has expired the server may have deleted them (and the
presence of a session id wouldn't change that behaviour)


> Yes, introducing a session id doesn't make it impossible to 
> do, but it does make it exponentially more difficult.  
> Difficult enough that an attack is unlikely to succeed, 
> whereas without it it is very possible.
>
> Compare basic authentication of username and password.  
> Guessing a username and password combination is much harder 
> than guessing one of the two.  And for large robust servers 
> (the reason we're using SOAP right?) there will be a lot of 
> users.  Unless the server is designed with this sort of 
> security in mind, the resultsets will probably just 
> identified with an incrementing scheme rather than a random 
> set of characters, so once a pattern has been found, the 
> server is completely compromised.

And session ids would be generated how? If there is a good algorithm for
generating session ids which isn't guessable why can't we use it for
record set ids?

And in any case a guessing an session id and result set id combination
is only as difficult as guessing a result set id of the same length as
the session id + result set id.

And what about situations (not necessary in SRW) in which a result set
id isn't being used? Aren't they more vulnerable since guessing a
session id alone is exponentially easier than guessing a session
id/result set id combination?

> User/password authentication has served for many years, and 
> will likely continue to do so for all but financially 
> important traffic.

There's nothing to stop SRW being used with username/password
authentication passed in the SOAP-Env:Header (or any other
authentication token for that matter) if that particular requirement is
needed.

> Yes.  But then you drastically limit the number of potential 
> clients to those that support encrypted SOAP.

Most toolkits I know that support SOAP over HTTP also support SOAP over
HTTPS

> It also makes 
> it more difficult to just throw together a server, I wouldn't 
> bother... > Z39.50 is less complex and more functional.

Again most SOAP toolkits run on http servers which support https out of
the box. Moving a SRW service from HTTP to HTTPS is normally just a
configuration change to the web server - hardly substantial "more
difficult". On the other hand, if you want to run Z39.50 in a secure
manner you would want to run Z39.50 over SSL or similar anyway
(especially in medical or financial scenarios). It is a little hard to
modify a Z39.50 toolkit to use SSL (not much, but it can require a
little recoding and recompiling) or you could use a SSL tunnel. Both of
these seem somewhat trickier than enabling https in a web server (which
is often just checking a box in the config tool).

The same situation applies to current websites (which maintain state
either via cookies or ids embedding in URLs or POST requests). Those
that are concerned about interception run on https, those that run
application where the risk analysis is such that it doesn't matter if
sessions are intercepted use http. As for mounting DDOS attacks there
are much easier ways to do that than guessing session ids (or result set
ids) and intercepting sessions (and which Z39.50 is immune to).

Matthew





Matthew

Top of Message | Previous Page | Permalink

Advanced Options


Options

Log In

Log In

Get Password

Get Password


Search Archives

Search Archives


Subscribe or Unsubscribe

Subscribe or Unsubscribe


Archives

July 2017
October 2016
July 2016
August 2014
February 2014
December 2013
November 2013
October 2013
February 2013
January 2013
October 2012
August 2012
April 2012
January 2012
October 2011
May 2011
April 2011
November 2010
October 2010
September 2010
July 2010
June 2010
May 2010
April 2010
March 2010
February 2010
January 2010
December 2009
October 2009
September 2009
August 2009
July 2009
May 2009
April 2009
March 2009
February 2009
December 2008
November 2008
October 2008
September 2008
August 2008
July 2008
June 2008
May 2008
April 2008
March 2008
February 2008
January 2008
December 2007
November 2007
October 2007
September 2007
August 2007
July 2007
June 2007
May 2007
April 2007
March 2007
January 2007
December 2006
November 2006
October 2006
September 2006
August 2006
July 2006
June 2006
May 2006
April 2006
March 2006
February 2006
January 2006
December 2005
November 2005
October 2005
September 2005
August 2005
July 2005
June 2005
May 2005
April 2005
March 2005
February 2005
January 2005
December 2004
November 2004
October 2004
September 2004
August 2004
July 2004
June 2004
May 2004
April 2004
March 2004
February 2004
January 2004
December 2003
November 2003
October 2003
September 2003
August 2003
July 2003
June 2003
May 2003
April 2003
March 2003
February 2003
January 2003
December 2002
November 2002
October 2002
September 2002
August 2002
July 2002
June 2002
May 2002
April 2002
March 2002
February 2002
January 2002
December 2001
November 2001
October 2001
September 2001
August 2001
July 2001

ATOM RSS1 RSS2



LISTSERV.LOC.GOV

CataList Email List Search Powered by the LISTSERV Email List Manager