Crypto: Kerckhoffs’ Principle

Kerckhoffs’ Principle is one of the keys to solid cryptographic security. Here is the definition I found on the Wikipedia:

“A Cryptosystem should be secure even if everything about the system, except the key, is public knowledge.”

Kerckhoffs’ Principle does not require that we publish or disclose how things work. It does require that the security of the system must not be negatively impacted by such a disclosure. A sub-theme of this principle, is that if the system is not negativly impacted by disclosure, it may be enhanced. 

In the history of cryptographic systems, peer reviewed systems/algorithms/techniques have outperformed closed/proprietary ones. This has its roots in basic human nature and is demonstrated every day in basic quality controls used for software in general.

A coworker once pointed out, “I am very confident that I can build a system that I cannot break. I am not so confident that I can build a system that no one else can break.” Getting many “someone else” resources to look at things is the core of Kerckhoffs’ Principle in practice, even if not in original intent. An example of using Kerckhoffs’ Principle is the current effort by NIST to sponsor the development and adoption of the next generation of hash algorithms through their hash contest (wiki, NIST). 

If You Need to Keep the “How” Secret…

If you need to keep the “how” secret, then odds are it isn’t a very good approach to the problem (and you may know that). I am often shocked when probing people on password protection, at how often their not wanting to disclose this information (because it is a “secret” itself) correlates to a very poor practice. 

BTW: the most frequent bad practice that I encounter over and over again is that “Base64 Encoding” is being used to “protect” the password. If I built a system that did that, I too would want to keep it a secret… ;-)

(In this case, I think the reluctance to disclose the information aligns more with “cover up” than “system design secret”.)

Kerckhoffs’ First Benefit: Peer Review and Collective Experience
(aka Not Being Dependent on Cleverness over Knowledge…)

It often seems odd to people that there are no secrets about how modern cryptographic algorithms are designed, operate, and are selected for broad usage.  Of course, I think many of these people don’t understand that this is no different from most security controls. Anyone can purchase a high-security lock, and then reverse engineer the lock. Take it apart, put it back together again, take it apart and examine (or replicate) each part, and so on. People’s trust in locks often greatly exceeds the actual “security” provided by the lock, but that has nothing to do with the fact that people have examined them. Most frequently it has more to do with people just purchasing cheap locks. 

Kerckhoffs’ Second Benefit: You Can Stand on The Shoulders of Giants

Back to passwords… Let’s say you are writing an application, and you need to store user account passwords. You are in luck – you can examine a broad body of work documenting the failures and redesigns of a number of password systems – and you can emulate what is working today without repeating old mistakes. The same can be said for a great number of security functions. 

It often amazes me how often people start with the blank page and reinvent the wheel. Personally, I don’t ever want to re-invent the wheel. If I do that, I will be lucky if I develop the wheel for a Roman ox cart, or bicycle. I would rather take what I can find out about the wheel and take it to the next level (maybe Formula 1 Ferrari Team Wheels…), or be done with that part of the system design quickly and focus on something more challenging. 

Kerckhoffs’ Third Benefit: Standards

Any time you are developing a solution to a problem and you can leverage a standards approach you are gaining numerous benefits. First, you are leveraging the “Standing on the Shoulders of Giants” concept by inheriting a body of work that has been tested, reviewed, etc. Second, it is easier to communicate it to others.

In the cryptographic world, there are a number of very helpful standards bodies. These include:

More soon…

Cheers, Erik

Optimize Your RSA, Part 3 – Network, Network, Network…

Probably this single most significant advantage to attending a conference, is the fact that it pulls so many people with a common interest into one place and time. If the interaction amongst participants wasn’t important, then it would be very difficult to make a compelling argument for in-person attendance.

Talk to People – Join in the Conversation

In the last year, I can think if 10 times where I was able to call (or I was called by) a colleague who I met at a past RSA. In the professional development series with Lee Kushner (link), ideas about developing, having, and being able to utilize your professional network are going to be a reoccurring theme.  If you are attending RSA (or any large event) don’t pass on the opportunity to meet and connect with new people. 

It can be Easy…

Don’t be mislead into thinking you need to “work the room” to meet people at RSA. 90% of the people who will be in Mascone Center are there because Information Security is important them, either as a practitioner or as a provider. (The other 10% are there to make sure everything runs smoothly.) 

So, you will be surrounded by people, who at least share that one item in common with you. Reaching out can be very easy. The people who you are in-line with, or waiting for a session to start with, etc. almost all do something connected to what you do. Just saying hello is all it takes. 

Leverage Events

There are a number of events that can make networking even more effective. The conference itself has roundtables session that are 100% focused on establishing peer to peer communication on targeted topics. Any vendor sponsored dinner or event also creates easy opportunities.

New to Networking? 

The RSA conference understands the value of the networking opportunity it is creating. As a result, there is a “Networking 101″ session on Monday evening at 5:15, immediately following the First-Time Delegate Orientation. Each year the conference brings in someone who has professional training experiencing in helping people network – helping people connect. This is always a great session to attend if you have the time, and are around the conference center on Monday evening.

Cheers, Erik

AoIS Interviews Lee Kushner, Part 1

Given the current economic situation, professional development and job searching are on many people’s minds. As a result, I saw no better time to get perspective on these topics from a true industry insider.

Lee Kushner is the President of LJ Kushner and Associates, LLC, an executive search firm dedicated exclusively to the Information Security industry and its professionals.  For the past thirteen years, Lee has successfully represented Fortune 2000 companies, information security software companies, information security services organizations, and large technology firms in enabling them to locate, attract, hire, and retain top level information security talent.  Throughout his career, he has provided career management and career coaching to information security professionals at various stages of their professional development.  He is a regular speaker and industry contributor on topics that include career planning, interview preparation, and employee recruitment and retention.

Erik: With 13 years of recruiting Information Security professionals, how has your position as a recruiter changed and evolved?

Lee: When I began recruiting 13 years ago, not many people had ever heard of a recruiter who specialized in Information Security – so there was a great burden of proof on my part to demonstrate that I understood both the technology and the industry to candidates.  Information Security professionals are a skeptical bunch.  It was very important to establish credibility and earn trust, by only promising what I was able to deliver.

I believe that after 13 years, both my firm and I have established a solid reputation and credibility within the industry and among the professionals.   Most of the people that we have worked with, we have done so for quite a while, throughout their career development.    Many of those professionals have passed on their positive experiences to their peers – and our reach has expanded.

It is my hope that through the years of working in the industry we have been able to help elevate the recruitment profession and inspire a different response when people hear the terms “recruiter” or “head-hunter”.

Erik: I understand that Mike Murray and you are working on a podcasting series called “Career Incident Response”? What is that about?

Lee: Mike and I have been speaking on the topic of Career Management for quite some time at RSA Conferences, DefCon, and The Source Conference.  We came up with the idea for a “Career Incident Response” podcast series due to the fact that so many people were coming to us either because they were a victim of a layoff, felt that a layoff was imminent, or had witnessed bad things happening to their industry peers.

The Career Incident Response podcast series will be outlined like a training course.  It will provide a guideline to what people can expect – from items that include evaluating your work situation,  the personal and emotional impact of job loss, how to effectively search for a position,  how to prepare your resume, and some basic ways to address difficult interview questions.

Note: The Podcast Series is scheduled for release on or about May 15th, 2009 on  http://www.infosecleaders.com.  Art of Information Security will post an announcement when the release happens.

Erik: If someone is working with a recruiter, what should they be doing to get the most value out of that relationship?

Lee: I believe that the most important item is honesty, which is driven by trust.  People generally like to keep things close to the vest when they are engaged in a job search and become cryptic about things such as timetable, other opportunities, their current work situation, and compensation.  The more accurate information that a recruiter has, the better that they can help assist you.

The other thing is that people should work with recruiters that understand their profession and can provide them with something more than a job description.  It should be imperative that the recruiter has industry experience, no matter which industry you are in.

For example,  if I was a real estate attorney, I would want to work with recruiters that either placed attorneys, or ones that worked with real estate clients.

Erik: What are some signs that people are working with the wrong recruiter for them?

Lee: The biggest sign is when they do not add any value to your search process that goes beyond the current opportunity that they are working on.  Many recruiters comb job boards and social networking sites, looking for key words, without understanding how they fit in.

Information Security is not a “key word” business.  There are many different segments of our industry and it is comprised of many different skill sets.   If a recruiter cannot differentiate between these skills and how you fit, then you are probably working with the wrong one.

Erik: If you could communicate one thing to someone who is trying to manage their career, what would that be?

Lee: The one thing that I would stress would be to strive to differentiate from your peers.  The industry is going to become more and more competitive, and competition for the best positions is going to increase, being able to tell that story is going to be critical to achieving your long term career goals.

Erik: In your practice, what are some of the key differentiators that you are encouraging people to pursue?

Lee: I hate to be vague, but the best thing that I can tell anyone is to make consistent investments in their career and career development.  This can include certifications, training, personal development, career coaching, etc – but investing in yourself and your career is going to be critical to differentiating from your peers and competition.

I have three rules when addressing self investment:  

  1. Any investment in your career is a good one
  2. You get what you pay for
  3. If you do not invest in yourself, do not expect anyone else to

Erik: You in fact have been working on a Career Investment and Differentiation presentation. What are some of the key points you are trying to communicate?

Lee: The key point of this concept is that it is up to you – the individual – to manage your career.  You are the one that has to seek out guidance, and plan for your future.   Do not expect your company to do it for you – you will reap the ultimate reward – so you should plan on making consistent sacrifices to attain these goals.

Erik: So, how much overlap should someone expect between their employer-driven professional development and their personal professional development?

Lee: Whatever you can gain from your employer’s personal development plan – by all means get.  However, you should understand why the employer is providing you with that stipend – it is so that it benefits them – not you.   If there is overlap – consider yourself fortunate.

Do not be tied to your employer’s career development plans – because you most likely have different plans for your career than your employer.   Develop your own career plan – and understand your skill deficiencies and try to find ways to eliminate them .  

Erik: So, you are really proposing that people treat their career as an asset that requires ongoing maintenance, just like their 401 (k) or home?

Lee: I believe that it is not only important to work “in” your career, but to work “on” your career.

Investing in your career and your personal development is the most important investment that you can make – because it is the one that you have the most control over.  In addition, once you learn something and develop a skill, it cannot be taken away from you (unless you decide to neglect it).

You can make very effective arguments that career acceleration produces the most effective long term financial rewards and improves the quality of your life.

Stay Tuned for Part 2 (link)

In the second part of our interview with Lee, he will discuss his recent presentation entitled “The 7 Habits of Highly Effective Career Managers”.

Cheers, Erik

Optimize Your RSA, Part 2 – Session Tips…

There is a TON of stuff to do at RSA if you are going, and managing all of that can be quite difficult. One of the things that I find difficult to do every year is select the sessions that I am going to. There are a few tools that the conference provides to make this easier.

Let’s take a look at the Session Catalog.

See Who’s Speaking

I have my own personal list of folks who always have great presentations and really pack a lot of punch for me. But, the attendance at the conference is so diverse that my list would certainly not work for everyone. The conference itself measures and metrics speaker performance. You know those forms they hand you as you walk into the session? Turns out that they use that data, and they even share it with you. When using the Session Catalog and the printed materials, you may notice a star next to some of the names. These are the folks who have had the strongest feedback during past conferences.

If this is your first RSA, it may be worth your while to ask folks who have attended in the past and who have similar interests, which speakers stood out to them. If you are a member of the RSA Conference group on Linked In (link), you could even post a question about “Best Session for X”. (Which I have done…)

Preview The Slides

RSA has always made the slides available in advance. Usually this was on media (CD/USB) handed out at the conference. (So, “in advance” was day-before…) But now they are available for most sessions right in the Session Catalog. (Note, you need to be logged in to the site before you visit the page to see these.)

Post Session…

There is a lot of time and energy that goes into being a speaker. Please, help your speaker and the conference, and complete the evaluation forms. And, if a session clicks for you – don’t be shy – meet the speaker. Most of the speakers are presenting because they are committed to the mission and the profession. Participation and feedback are the biggest rewards any speaker can ask for from the audience – don’t hold back.

Hope this is helpful – see you in SFO.

Cheers, Erik

Optimize Your RSA, Part 1 – Expo Management

It is one week until RSA, and now is the time to start planning to make the most of your trip. RSA has one of largest (if not the single largest) vendor Expositions for Information Security. Every year I use this as a one-week refresher course on the products and services that are available. Frequently the class sessions are very valuable to me, in terms of my long term professional development, but  (for my employer) the information I collect on the Expo floor is valuable almost immediately.

Screen Now and Benefit All Year

I am very selective about the vendors with whom, I have  meetings.  Sure, I am missing out on free lunches, but the fact is that I don’t have endless time to meet with people.  As a result I screen, and whenever possible pre-qualify vendors. Most of the time I spend on the RSA Expo floor is spent identifying who I don’t need to meet with, and establishing whom I definitely do want to meet with in the following year.

Understand your Organizations or Clients Needs !

In general you should have a good understanding of your employer or clients… Some key things to understand before heading out to the exposition:

Q: What are the emerging needs of your organization?

What are the areas of concern for your CISO, Risk Mgmt., LOB partners, or other important constituents? In the week or two leading up to RSA, I ping my CISO, key LOB partners, etc. to find out what concerns they have, what vendors have been hounding them for meetings, what alternatives they may need, etc.

Q: What products or services are subject to change?

I feel that, even for our deployed products, it is incumbent on me as a good corporate citizen to make sure those products are still competitive in the market. Information about the competition is especially important during contract renewals. No one negotiates a win-win deal without being fully informed.

Q: Who are you key partners, and what new offerings do they have?

Who are the top vendors whose products you have, and love? Make sure to take the opportunity to visit them, understand emerging features, and make sure that you are getting the most out of your existing investment.

Q: Who will your organization generally buy or not buy from?

Many organizations have firm rules about the types of organizations they will purchase from; know what these are. My experience is that if a product is truly compelling, there is always a way for purchasing to see that and make a deal happen. But, if you sense a weak offering from a company, that is going to be a hard sell to your organization, save time for both you and the vendor – tell them, and move on.

Be There Monday Night

Monday evening at RSA, the Expo opens to Delegates only. The fact that there are fewer people on the expo floor, the booth people are not burned out, and the free food makes this the ideal Expo floor time.

Arrange Key Visits In Advance

As I already mentioned, I try to pre-qualify vendor meetings. There are folks whom I know that I need to be meeting with (established relationships, emerging solutions, emerging risk needs, etc.) and there are a number of folks I know I don’t want to wast time on (lack of compelling product story, people who wasted my time in the past,etc.), but there are also a number of folks in the gray area in-between.

From November on, I start asking folks in the gray area if they are going to have an Expo presence at RSA. If they are, I ask for them to follow-up with me before the show with a booth # and contact name. After I arrive on-site and have the conference book in hand, I add to the list. I avoid setting up specific times, because with everything that happens at the show my schedule is too dynamic.

For each of these “quick meet and greets”, I prep one of my business cards in advance. I have the booth #, contact name, and subject clue on the back of the card. If my contact isn’t at the booth, I leave the card. When you in fact follow-up, you build credibility and relationship, even if there is no service to need synergy at this time.

Be Quick and Targeted

If the printed information, name, etc. on the booth catches my eye, I stop for a quick visit. I try to get the facts quickly, in 3-6 min. The secret is to not be afraid to ask tough questions quickly (but politely), such as:

  • What’s compelling about your offering?
  • Who is your primary competition?
  • Do you have hard data, or a case study you can forward to me?
  • Do you have reference accounts for the use cases that are most important to my organization?
  • What industry analysis (Gartner, Burton, etc.) has been published on this space? Was your product included?

Be Specific About Follow-up

If I have an immediate need, I ask for contact info and I initiate the follow-up before I leave the show. If I am interested in follow-up for a long-term, or next budget cycle, etc. then I usually ask for follow-up later in the year (e.g. Q3/4). Q2 is always a very busy time for me and the people around me, so I try to defer long-term information and knowledge capture until later in the year.

Hope this is helpful – see you in SFO.

Cheers, Erik

Max the Identity & Access Management in Your RSA 2009…

If you are attending the Pre-Conference 1-day Tutorial, Building an Enterprise-Strength Identity & Access Management Architecture, that Dan Houser and I are co-teaching at RSA 2009 please take a moment to drop me a note (using the “Contact Erik” link from the site). This years class is going to be much smaller than last year and should allow for more interaction. As a result, I would like to take the opportunity to maximize the value of that increased interaction, and knowing what topics are top-of-mind for participants in advice will help. 

If you are attending RSA 2009, and plan to be in San Francisco all day on Monday, take a look at the available Pre-Conference 1-day Tutorials (RSA has added a number, and there are many to choose from). There is an additional fee for these Tutorials but based on the feedback from last years class, it was worth it.

Neither Dan nor I work for a vendor or supplier in the space.  We both work for Fortune 500 corporations that have real-world Identity and Access Management challenges (with real-world obstacles). If you are a Linked In member, profile (link) has some endorsements related to this class, as well as other presentations.

Cheers, Erik

AoIS Interviews Michael Rash, Part 3

Michael Rash HeadshotThe Art of Information Security continues our interview with Michael Rash, Network Security expert and the driving force behind several open source security tools including PSADFWSnort, and FWKnop.

In Part 2 of the interview Michael discussed how network threats, and network counter measures have been evolving. He also touched on the development of his book. Here goes the final installment in this series…

Erik: What would be your recommendations for folks who are adopting Linux (either enthusiasts or corporations) in terms of properly protecting their hosts and networks from network attacks?

Michael: I think that deploying host and network firewalls is a great first step here, and iptables functions admirably. Many people in corporate environments are concerned about the questions of performance, manageability, scalability, and support, and iptables together with some third party software have decent answers to these concerns. For example, the fwbuilder project provides good graphical support for the display and manipulation of iptables policies, and large Linux distributions such as Red Hat and SuSE offer commercial support.

Beyond having proper firewalls deployed, intrusion detection systems are a critical piece to point the way to attempted (and sometimes successful) compromises. Also, strong security mechanisms such as SELinux can provide a powerful barrier to attempted malicious usages of hosts. Finally, patch early and patch often.

Erik:  Do you have any tool or reference recommendations for debugging IP tables firewalls?

Michael: For debugging iptables policies and maintaining tight controls on the type of packets that are allowed to traverse those policies, one of the best techniques is to use tcpdump either on the end points or on the firewall itself (and these may be the same system) and watch how network traffic is allowed to progress. For example, a SYN packet to a port that is filtered will not respond either with a SYN/ACK or a RST, and seeing this behavior with tcpdump is quite easy. At the same time, understanding where in an iptables policy packets are getting dropped (or otherwise messed with) is usually made clear by watching how packet and byte counters are incremented on particular iptables rules. Use ‘iptables -v -n -L’ for this, and couple this with the ‘watch’ command to see how things change. Beyond this, if you have a kernel compiled with support for the iptables TRACE target, then you can use an iptables TRACE rule that causes all packets hitting this rule to be logged. Lastly, for really advanced debugging of iptables code itself, the nfsim project provides a simulator for running Netfilter code within userspace (and hence the ability to test code before running it within the kernel itself where a bug can have dire consequences). The nfsim project can be found here:

http://ozlabs.org/~jk/projects/nfsim/

Erik: So, you obviously are deeply connected to all things Network IDS/IPS. What kinds of trends have you seen in 2008? Were there any new attack styles that surprised you? Do you have any ideas about what 2009 may hold?

Michael: Well, 2008 will certainly go down in history as the year that people were forced to really pay attention to DNS by the Kaminsky attack. One thing Dan did really well is make it clear just how important DNS is for literally everything on the Internet, and how a flaw there has implications that are difficult to over estimate. Online banking, acquiring SSL certificates, SMTP, “forgot my password links”, and countless other infrastructures depend on DNS information being correct. But, then there were also serious issues in 2008 with BGP and with SSL, so if there was any trend in 2008 I would say that it was the year of security flaws in big Internet infrastructures. In 2009, it will be interesting to see whether this trend remains true for as-yet undiscovered vulnerabilities in other important systems.

Erik: Has your support for open source helped you professionally?

Michael: Absolutely. My current position as a Security Architect on the Dragon IDS/IPS developed by Enterasys Networks is a role that my open source work helped me to acquire. Many forward looking innovations are created by the open source community, and understanding this community helps to guide many companies and the products they develop. Companies are recognizing the power of open source software more and more, and this translates to better professional positions for open source developers and technology enthusiasts.

Many Thanks to Michael !

Thanks a ton for the time and energy you put into this, the first of what I hope will be many, interviews with notables from around the Information Security community.

Thanks, Erik