[Esapi-user] Recommending ESAPI?

Jim Manico jim.manico at owasp.org
Tue Jan 12 06:54:15 EST 2010

You know Dinis, when I first read your email I was bit offended. Same
with much of John Stevens' email.

But you know? You are trying to help us. These kinds of pragmatic
questions need to be answered.

So here goes.

> Following the recent thread on Java 6 security and ESAPI, I just would
> like to ask the following clarifications: 
> 1) For an existing web application currently using a MVC framework
> (like Spring or Struts) are we today (9th Jan 2009) officially
> recommending that this web application development team adds OWASP's
> ESAPI.jar to the list of 'external' APIs (i.e. libs) they use, support
> and maintain?

I can personally attest for ESAPI 2.0 rc4 integration into Struts 1.3.x,
where I've used ESAPI for several years, from the early days. I'm not
deeply familiar with Spring. I would not say this is a trivial exercise,
but it certainly is possible.

> 2) When adopting the OWASP ESAPI's J2EE implementation, is ESAPI.jar
> ALL they need to add? or are there other dependencies (i.e. jars) that
> also need to be added, supported and maintained? (for example on the
> '*Dependencies' section of the ESAPI Java EE
> <http://www.owasp.org/index.php/Category:OWASP_Enterprise_Security_API#tab=Java_EE> page
> (i.e. Tab) it seems to imply that there are other *.jars needed)*

ESAPI.jar has significant dependencies - something that is a problem, in
general, in the Java world. I'm optimistic about the new Java 7
component framework - but that is a long way off.  In the meantime:


/There are no dependencies on the ESAPI *interfaces* other than standard
Java EE. However, the reference implementation does have dependencies
that are detailed below. The reference implementation takes advantage of
a few existing libraries. _*This list may not be totally complete.*_ /

    * /DefaultAccessController needs... /
          o /Commons-Configuration 1.5 /

    * / DefaultValidator needs... /
          o / AntiSamy 1.2 (there may be a few transitive dependencies
            here) /
          o / NekoHTML 0.9.5 /
          o / Xerces 2.9.1 /

    * / Log4J Logger needs... /
          o / Log4j 1.2.12 /

    * / DefaultHTTPUtilities needs... /
          o / Commons-FileUpload 1.2 /

    * / WAF needs /
          o / XOM 1.0 (there may be a few transitive dependencies here) /
          o / Commons-FileUpload 1.2 /

> *
> *
> 3) Where can I find detailed information about each of the 9 Security
> Controls that ESAPI.jar currently supports: 1) Authentication,
> 2) Access control, 3) Input validation, 4) Output encoding/escaping,
> 5) Cryptography, 6) Error handling and logging, 7) Communication
> security, 8) HTTP security and 9) Security configuration? (I took this
> list of controls from the Introduction to ESAPI pdf)
> <http://www.owasp.org/images/8/81/Esapi-datasheet.pdf>

Detailed from a marketing perspective? :) The best technical information
is our Javadoc pages at
which are not complete, but are fairly decent. We have also been very
good about answering questions, fast, on esapi-users and esapi-dev. But
you are right - docs are evolving, but we need more.

> *4) When adopting EASPI.jar, are we recommending that the developers
> should adopt or retrofit their existing code on the areas affected by
> those 9 Security Controls? (i.e. code related to:
> Authentication, Access control, Input validation, Output
> encoding/escaping, Cryptography, Error handling and logging,
> Communication security, HTTP security and Security configuration)*
> **
It really depends on the situation. But I get your point - I've seen the
Validator, Encoder, Utils and Error Handling modules used in
retrofitting situations successfully. I'm not so sure about the others.
> *
> *
> *5) Should we recommend the adoption of ALL 9 Security Controls? or
> are there some controls that are not ready today (9 Jan 2009) for
> production environments and should not be recommended? (for example is
> the 'Authentication' control as mature as the 'Error handling and
> logging' control?)*
I personally grade the reference 2.0 implementation as follows:

1) Authentication   C (Needs deeper enterprise integration)
2) Access control   B- (This is just a really tough issue, and usually
requires deep application-specific context. Plus we have some good ideas
on the table from Beef that I'd like to consider)
3) Input validation   A- (needs better messaging and
internationalization (thanks Sklarew for making us think in the right
direction about this)
4) Output encoding/escaping   A (Go Jeff, my only A. :) We do need a
performance tuning pass (easy) and DOM XSS encoding functions)
5) Cryptography  A- (Great work Kevin, this is a huge huge improvement
from 1.4)
6) Error handling and logging  B+ (Nice work on designing this from Wichers)
7) Communication security ?
8) HTTP security B- (Great utilities! I'd like to see some of these
decoupled a bit more)
9) Security configuration ?

Digging deeper....

I personally use almost all of ESAPI. I've written my own Hibernate
Authentication layer - but it's very specific to my data model. It's
very difficult to decouple this from my app and would be difficult to
donate it to the project effectively. Same with access control. My data
model is VERY complex, and donating it without SQL scripts, hibernate
configuration, and a whole lot of other code - is a great challenge.
(Not to mention that my employer owns the code ;) The flat-file
authenticator is just a proof of concept and should never be used in a
production environment of any kind, IMO. The thread-local nature of the
authenticator, while I use it and love it, needs to be reconsidered
since other classes, like the loggers, depend on it. Error handling is
fairly solid - and is only a thin layer on top of known logging methods
+ security specific messaging. The encoder was handed down from Gosling
himself - given to Jeff - who gifted it to us. :) I want the encoder to
be a hard-coded part of ESAPI. :) The validator and encoder can be
dropped into any project fairly easy. Same with much of the HTTP Utils.
The Encryptor from 1.4 should be avoided, which impacts other portions
of the codebase.
. 2.0 is going to be a very big milestone; I'm pretty stoked about what
I'm seeing from the team.

Most importantly, it's easy to use the ESAPI configuration layer to
over-ride any of the reference implementation with your personal
authenticator or access controller (so long as you implement the ESAPI
interfaces), as I have for my projects.

> *
> *
> *6) Are there commercial (i.e. *paid) *support services available for
> the companies who want to add ESAPI.jar to they application?***

I hesitate to mention this, and I'm not trying to pimp - but I'm
respectfully answering all of your questions. Aspect offers these
services. I've been working with Jeff on some of those efforts. It's
working out well for Aspects clients, I'd dare say. If someone else
wishes to speak up on this topic, please do. Open.
> *
> *
> 7) What is the version of ESAPI.jar that we should recommend? the
> version 1.4 (which looks like a stable release) or the version 2.0 rc4
> (which looks like it is a Release Candidate)
ESAPI 1.4.1 is *very *far behind 2.0 rc4.  Java 4 is way past end of
lifecycle - but it's still in very wide use, so we plan to back-port all
of ESAPI 2.0 to 1.4. Or at least as much as we can. I'm making some
changes this week and plan on releasing 1.4.2 this week.
> 8) Where can I find the documentation of where and how ESAPI should be
> used? More importantly, where can I find the information of how it CAN
> NOT or SHOULD NOT be used (i.e. the cases where even when the
> EASPI.jar are used, the application is still vulnerable)
Yea, Docs. We need more docs. Boberski has done incredible work in this
> 9) if there list of companies that have currently added ESAPI.jar to
> their applications and have deployed it? (i.e. real world usage of EASPI)
Under "users and adopters"
> 10) Has the recommended ESAPI.jar (1.4 or 2.0 rc4) been through a
> security review? and if so where can I read its report?
Yes and see #8 sentence 2.
> 11) /*when Jim says /"... you can build a new secure app without an
> ESAPI. But libs like OWASP ESAPI will get you there faster and
> cheaper....", / *do we have peer-reviewed data that suports this claim?
> /
Nope. I'm shooting from the hip and I consider this as common sense. But
I agree, we REALLY need more assurance evidence that is published on the
wiki - perhaps we should run o2 against the ESAPI codebase for starters.
Or maybe someone can donate code review services and publish that report
on our wiki. I hear you. Assurance, published assurance, is fundamental.
> /
> /
> /12) Is there a roadmap or how-to for companies that wish to adopt
> ESAPI.jar on an a) new application or b) existing real-world
> application'?/
See #8 sentence 2.
> /
> /
> /13) What about the current implementations of ESAPI for the other
> languages. Are we also recommending their use?/
Most are beta or alpha - with sparkles of 1.0. But I'd love to hear the
other language leaders chime in here. I focus on the Java version of ESAPI.
> /
> /
> /14) If a development team decides to use (for example) Spring and
> ESAPI together in their (new or existing) application, what are
> the recommended 'parts' from each of those APIs (Spring and EASPI)
> that the developers should be using? (for example: a) use Encoding
> from ESAPI, b) use Authentication from Spring, c)
> use Authorization from ESAPI, d) use Error Handling from Spring, e)
> use Logging from ESAPI, etc...)/

I just don't know how to answer this question. I think for starters, the
completeness of our encoder helps stop XSS cold in a way that is a bit
better than the frameworks. And Jeff authorer a great cheat sheet to go
alongside it.

> /
> /
> /Thanks/
> /
> /
> /Dinis Cruz/
/I'm not going to shy away from these emails any longer. Is this all you
got, Dinis? John Steven? Bring it on, I'll do my best to answer as
honestly as I can.

But let me tell you, Dinis. I would not consider building any Java app
without ESAPI. :) (please note the "I" statement - I've been deep in the
code for years, I'm not saying its easy - it requires significant
investment of time to use all of ESAPI as it stands today).

Another 18 hour day - I need sleep. :)

- Jim
-------------- next part --------------
An HTML attachment was scrubbed...
URL: https://lists.owasp.org/pipermail/esapi-user/attachments/20100112/bca76754/attachment-0001.html 

More information about the Esapi-user mailing list