Traditional block ciphers work on fixed blocks of data—as an example, AES is well-defined for 128/192/256 bits. But one of the issues is the need for padding—so if you need to encrypt small amounts of data you may end with a huge difference in input vs. output size. As an example, using AES/128 on ECB mode to encrypt an IPv4 address results in an input size of 32 bits, but an output size of 128 bits. This may not be desired for some applications.
To address such needs, we have designed the FNR encryption scheme. FNR stands for Flexible Naor and Reingold. Our proposed encryption scheme is a practical variant of Naor and Reingold’s work. We are releasing the reference implementation of the FNR encryption scheme under open source license LGPLv2.
FNR is an experimental small domain block cipher for encrypting objects (< 128 bits) like IPv4 addresses, MAC addresses, arbitrary strings, etc. while preserving their input lengths. Such length preserving encryption would be useful when encrypting sensitive fields of rigid packet formats, database columns of legacy systems, etc. in order to avoid any re-engineering efforts for privacy preservation.
Enrollment over Secure Transport (EST) is a new standard (RFC7030) designed to improve the lifecycle management of digital certificates, a key element for secure communications. Cisco Engineer Max Pritikin coauthored the EST standard.
We’re very excited about the potential use cases of EST, which are, as we’ll discuss in a moment, pretty versatile.
To understand EST and how it works, let’s look at a basic use case: A controller, such as a Wi-Fi access point, manages an endpoint. To secure the management communication, both the controller and the endpoint authenticate each other using certificates. EST is a new way to obtain those certificates that is more secure and comprehensive than previous approaches, such as Secure Certificate Enrollment Protocol (SCEP). One area EST is superior to previous approaches is that it enables the use of Cisco’s Next Generation Encryption (NGE), which uses Elliptic Curve Cryptography (ECC) to get the job done as opposed to RSA encryption. That’s a lot of acronyms, so let’s take a step back to explore what this all means.
The next level of encryption
Today’s modern threats demand a new standard of encryption. Cisco’s move to NGE is paving the way for the next decade of cryptographic security. NGE provides a complete algorithm suite that is comprised of authenticated encryption, elliptic-curve based digital signatures and key establishment, and cryptographic hashing. These components provide high levels of security and scalability, aimed at protecting critical data and setting the standard for encrypting sensitive data in networks all over the world.
These cryptographic technologies meet the evolving needs of governments and enterprises by using innovative, battle-tested cryptographic algorithms and protocols, and are beginning to be used in place of legacy cryptographic approaches. EST drives the adoption of ECC, strengthening Cisco’s products and in turn strengthening the security posture of our customers.
EST can be used for a variety of purposes. Enterprises with a number of network endpoints require the “re-enrollment” (re-issuance) of certificates every period, potentially every year. This helps prevent servers going offline due to expired certificates, and the ensuing scramble to obtain and install updates. EST enables automatic re-enrollment to obtain a new certificate, making this a faster and less labor-intensive process. Additionally, EST supports automatic redistribution of CA certificates when they are updated. These improvements are immediately valuable and will be very important for future Internet of Everything (IoE) environments where the large numbers of endpoints will make certificate management highly complex.
Protecting against modern threats
For another example of how EST can help protect the modern network, look no further than your home page and the daily news. The recently discovered Heartbleed bug has thrown the industry into a panic, with enterprises, consumers, and organizations scrambling to assess the fallout and determine an appropriate remediation strategy. Many sites are recommending the replacement of certificates. If EST were in wide deployment, its re-enrollment capabilities would significantly reduce the impact of refreshing the server certificate, supporting much more rapid resolution of the security vulnerability.
As an open standard, EST will increase interoperability with other company’s offerings, including our CA partners. Cisco has taken steps to accelerate adoption and interoperability by providing EST software in the open source community, through Github. Even at this early stage, we’re seeing some positive feedback. Phil Gibson, chairman of the PSNGB, the Industry Trade Association for Public Services Networks (PSN) suppliers, said: “The Public Services Network is now the primary infrastructure for the majority of government communications in the UK and the encryption solutions it uses must continue to evolve. Due to the large and varied number of encryption devices in use, a scalable certificate provisioning protocol is critical to the migration to next generation encryption (CESG PRIME). Cisco’s release of its EST code into the open source community will facilitate rapid adoption by the PSN community. With the release of this code, other vendors will be able to accelerate their adoption of EST and this in turn expands the choice of encryption solutions available to public sector organizations.”
This is an overview of what we can do with EST, and we’re just getting started. We have started to build libraries to incorporate EST into Cisco products, which will likely begin later this year or early next. Stay tuned for additional updates over the coming months.
Based on 25 years of professional experience in various businesses around the globe, I can say that many industry verticals have a pretty good state of safety culture as it relates to the health and safety of their employees. This is especially true for companies involved in high-risk businesses such as oil and gas, (nuclear) energy, manufacturing, chemicals, food processing, and so on. In such industries, it is pretty clear that there is a risk that something may blow up, hurt, or even kill people.
However, it seems that the next big driver for them is business alone, and they are not as focused on information or IT security when it comes to the logic side of security like bits and bytes, document handling of confidential information, and similar subjects. This is in stark contrast to their keen attention to physical safety and security issues.
It would seem intuitive that any organization with a commitment to safety by counting (and incentivizing) the hours (days, weeks, months, …) of safety-incident-free time should also be easy to convince that taking a similar approach to information security would be a good thing. But it is not that easy. Operations in these businesses are very physical, so it is not really in the mind-set of a rig guy or gal, a welder, a component mixer, machine operator, or similar, that another devastating incident (attack) could happen from “within” the system(s), by a human adversary committed to do harm in the interest of their nation state or paying agent. All those systems in the above mentioned industries that are working at the process level (sensors/actuators, process control, SCADA (supervisory control and data acquisition) are designed for efficient and effective, good performing, and reliable operation, but they were not really designed and built to resist logic attacks from a human smart guy who can outsmart almost every defense.
In industrial networks, spanning the areas of instrumentation, control bus, operations, business, or enterprise, the often cited Purdue reference model that provides for several “levels” or “zones” of abstraction and segregation can be used. A really good introduction can be found in the Secure Data Transfer Guidance for Industrial Control and SCADA Systems.
A few months ago we discussed the various ways that consumer PII is compromised. The recent attacks against Target and Neiman Marcus illustrate the constant threat that payment card accepting retailers of all sizes face. Yesterday Reuters reported that similar breaches over the holidays affected “at least three other well-known U.S. retailers”. Given the current onslaught, it’s a good time for retailers to examine their detection capabilities before a payment card data attack, while creating new goals for shortening remediation windows during and after an attack.