Errata: Version 1.1 of the paper, reference, and optimized code corrects an error in which the length of the configuration string was passed in as the size of the internal block (256 bits for Skein-256, 512 for Skein-512, and 1024 for Skein-1024), instead of a constant 256 bits for all three sizes. This error has no cryptographic significance, but affected the test vectors and the initialization values. The revised code also fixes a bug in the MAC mode key processing. This bug does not affect the NIST submission in any way.

NIST has received 64 submissions. (This article interviews one of the submitters, who is fifteen.) Of those, 28 are public and six have been broken. NIST is going through the submissions right now, making sure they are complete and proper. Their goal is to publish the accepted submissions by the end of the month, in advance of the Third Cryptographic Hash Workshop to be held in Belgium right after FSE in February. They expect to quickly make a first cut of algorithms -- hopefully to about a dozen -- and then give the community about a year of cryptanalysis before making a second cut in 2010.

Lastly, this is a really nice article on Skein.

These submissions make some accommodation to the Core 2 processor. They operate in "little-endian" mode (a quirk of the Intel-like processors that reads some bytes in reverse order). They also allow a large file to be broken into chunks to split the work across multiple processors.

However, virtually all of the contest submissions share the performance problem mentioned above. The logic they use won't optimally fit within the constraints of a Intel Core 2 processor. Most will perform as bad or worse than the existing SHA-1 algorithm.

One exception to this is Skein, created by several well-known cryptographers and noted pundit Bruce Schneier. It was designed specifically to exploit all three of the Core 2 execution units and to run at a full 64-bits. This gives it roughly four to 10 times the logic density of competing submissions.

This is what I meant by the Matrix quote above. They didn't bend the spoon; they bent the crypto algorithm. They moved the logic operations around in a way that wouldn't weaken the crypto, but would strengthen its speed on the Intel Core 2.

In their paper (PDF), the authors of Skein express surprise that a custom silicon ASIC implementation is not any faster than the software implementation. They shouldn't be surprised. Every time you can redefine a problem to run optimally in software, you will reach the same speeds you get with optimized ASIC hardware. The reason software has a reputation of being slow is because people don't redefine the original problem.

That's exactly what we were trying to do.

District Court Holds that Running Hash Values on Computer Is A Search: The case is United States v. Crist, 2008 WL 4682806 (M.D.Pa. October 22 2008) (Kane, C.J.). It's a child pornography case involving a warrantless search that raises a very interesting and important question of first impression: Is running a hash a Fourth Amendment search? (For background on what a "hash" is and why it matters, see here).

First, the facts. Crist is behind on his rent payments, and his landlord starts to evict him by hiring Sell to remove Crist's belongings and throw them away. Sell comes a cross Crist's computer, and he hands over the computer to his friend Hipple who he knows is looking for a computer. Hipple starts to look through the files, and he comes across child pornography: Hipple freaks out and calls the police. The police then conduct a warrantless forensic examination of the computer:

In the forensic examination, Agent Buckwash used the following procedure. First, Agent Buckwash created an "MD5 hash value" of Crist's hard drive. An MD5 hash value is a unique alphanumeric representation of the data, a sort of "fingerprint" or "digital DNA." When creating the hash value, Agent Buckwash used a "software write protect" in order to ensure that "nothing can be written to that hard drive." Supp. Tr. 88. Next, he ran a virus scan, during which he identified three relatively innocuous viruses. After that, he created an "image," or exact copy, of all the data on Crist's hard drive.

Agent Buckwash then opened up the image (not the actual hard drive) in a software program called EnCase, which is the principal tool in the analysis. He explained that EnCase does not access the hard drive in the traditional manner, i.e., through the computer's operating system. Rather, EnCase "reads the hard drive itself." Supp. Tr. 102. In other words, it reads every file-bit by bit, cluster by cluster-and creates a index of the files contained on the hard drive. EnCase can, therefore, bypass user-defined passwords, "break down complex file structures for examination," and recover "deleted" files as long as those files have not been written over. Supp. Tr. 102-03.

Once in EnCase, Agent Buckwash ran a "hash value and signature analysis on all of the files on the hard drive." Supp. Tr. 89. In doing so, he was able to "ingerprint" each file in the computer. Once he generated hash values of the files, he compared those hash values to the hash values of files that are known or suspected to contain child pornography. Agent Buckwash discovered five videos containing known child pornography. Attachment 5. He discovered 171 videos containing suspected child pornography.

One of the interesting questions here is whether the search that resulted was within the scope of Hipple's private search; different courts have approached this question differently. But for now the most interesting question is whether running the hash was a Fourth Amendment search. The Court concluded that it was, and that the evidence of child pornography discovered had to be suppressed:

The Government argues that no search occurred in running the EnCase program because the agents "didn't look at any files, they simply accessed the computer." 2d Supp. Tr. 16. The Court rejects this view and finds that the "running of hash values" is a search protected by the Fourth Amendment.

Computers are composed of many compartments, among them a "hard drive," which in turn is composed of many "platters," or disks. To derive the hash values of Crist's computer, the Government physically removed the hard drive from the computer, created a duplicate image of the hard drive without physically invading it, and applied the EnCase program to each compartment, disk, file, folder, and bit.2d Supp. Tr. 18-19. By subjecting the entire computer to a hash value analysis-every file, internet history, picture, and "buddy list" became available for Government review. Such examination constitutes a search.

I think this is generally a correct result: See my article Searches and Seizures in a Digital World, 119 Harv. L. Rev. 531 (2005), for the details. Still, given the lack of analysis here it's somewhat hard to know what to make of the decision. Which stage was the search — the creating the duplicate? The running of the hash? It's not really clear. I don't think it matters very much to this case, because the agent who got the positive hit on the hashes didn't then get a warrant. Instead, he immediately switched over to the EnCase "gallery view" function to see the images, which seems to be to be undoudtedly a search. Still, it's a really interesting question.

• Love, love, love this piece :-) Remember the "robotic gun rampage" stories from last year? How does this sound: "The gun can track 360 degress, but there is a software-driven safety zone that makes sure rounds don't blow the rotors off. If the Osprey has to maneuver away from the target and the crew chief can't hold the gun on the bad guys manually, the system slaves the gun to the point of the last shot, slewing it as the plane moves." (watch the fun video there too)
  
• "Security idiot" meme lives on - go here. BTW, the post is a follow-up to this
• A fun follow-up to my post on compliance approaches titled Is PCI DSS "Too Prescriptive"?
• Finally, my fave post: "Increase Your Logging." I am sooooo happy that logging evangelism is spreading far and wide! A quote from the paper: ”Logs are interesting, logs are fun, logs should be done by EVERYONE…..get to logging!!!” (I promise that specific case was not my quote, even though I do say that very thing all the time!)
  

Rather than thinking about IDS as a piece of device/software that provides fancy features. Let me try to summarize some assertions about IDS: 

IDS can capture tons of intrusion events, there is so much of don't care events it is difficult to single out event such as zero day event in the midst of such noise.

It requires tremendous effort to sift through the log and derive meaningful actions out of the log entries.

IDS needs a dedicated administrator to manage. An administrator who won't get bored of looking at all the packets and patterns, a truly boring job for a security engineer. Probably this job would interest a geekier person and geeks tend to their own interesting research!

There are companies that do without IDS, and they do just fine. I agree with Alan's assessment that IDS is like a Checkbox in most cases.  Business can run without IDS just fine, why invest in such a technology?

Firewalls and other devices have built in features of IDS, so why invest in a separate product.

IDS is like Vitamins, nice to have, not having won't kill you in most cases. Customers are willing to pay for Pain Killers because they have to address their pain right away. For Vitamins, they can wait. Stop and think for moment, without Anti-virus product, businesses can't run for few days. But, without IDS, most businesses can run just fine and I base it out of my own experience.

Probably, I would have offended folks from the IDS camp. I have a good friend who is a founder of an IDS company, I am sure he will react differently if he reads my narratives about IDS.  Once businesses start realizing that IDS is a Checkbox, they will scale down their investments in this area. In the current economic climate, financial institutions are not doing well. Financial institutions are big customers in terms of security products, with the current scenario of financial meltdown, they would scale down heavily on their spending on Vitamins.

Running IDS software on VMware sounds fancy.  Technology does not matter unless you can address real world pain and prove the utilitarian value of such a technology. I am really surprised that IDS continues to exist. Proof of existence does not forebode great future. Running IDS on VMware does not make it any more utilitarian. I see a bleak future for IDS.

The technologies, generally regarded as promising but unproved, have yet to be widely accepted as evidence — except in India, where in recent years judges have begun to admit brain scans. But it was only in June, in a murder case in Pune, in Maharashtra State, that a judge explicitly cited a scan as proof that the suspect’s brain held “experiential knowledge” about the crime that only the killer could possess, sentencing her to life in prison.

[...]

This latest Indian attempt at getting past criminals’ defenses begins with an electroencephalogram, or EEG, in which electrodes are placed on the head to measure electrical waves. The suspect sits in silence, eyes shut. An investigator reads aloud details of the crime — as prosecutors see it — and the resulting brain images are processed using software built in Bangalore.

The software tries to detect whether, when the crime’s details are recited, the brain lights up in specific regions — the areas that, according to the technology’s inventors, show measurable changes when experiences are relived, their smells and sounds summoned back to consciousness. The inventors of the technology claim the system can distinguish between people’s memories of events they witnessed and between deeds they committed.

AT&T now says that any "FastConnect" subscription, even its DSL Lite offering of 768 Kbps down/128 Kbps up, qualifies for Wi-Fi Basic. The new statement reads: "AT&T Wi-Fi Basic service is FREE and already included if you subscribe to AT&T High Speed Internet, AT&T U-verseSM High Speed Internet, or AT&T FastAccess® DSL—all speed plans included.

There's still a $10 per month fee to upgrade to Wi-Fi Premier, which includes over 70,000 locations worldwide, along with the missing U.S. hotspots, but their Web site says that you have to have a 1.5 Mbps or faster connection to get the $10 per month upgrade. That may be out of date. That ordering page also says you need 1.5 Mbps or faster for free Wi-Fi, so that tends to confirm it hasn't been fixed. (It's even hosted at sbc.com, so perhaps that's part of the vestige of an older system, harder to update.)

Please note that iPhone subscribers still don't get free Wi-Fi on AT&T's Basic network.

coconutBattery — This little app tells you more info about your battery’s quality of life. Namely, I’ve been having a frustrating problem — my laptop acts like it’s at 0% and shuts down, even when the power meter reads upwards of 10-30%… According to coconutBattery, my battery’s only operating about 80% of its original capacity. Maybe that’s my problem… It also allows you to save its stats so you can monitor your battery over time.

coconutWifi — Many Mac controls are easier to use than Windows — but the Airport card isn’t always one of them. Unlike on a Windows machine, it doesn’t tell you which networks in the area are encrypted. This little app changes that with a handy icon telling you how many open networks are available, and not only that — it also lets you know what channels they’re all using. Now I can easily increase the range of my network by setting it to an unused channel.

Excuse me, I have to go play with my new utility toys…

During the presentation I mentioned in some depth how to perform fuzz testing, and what parts of an application should be fuzz testing targets. I also introduced an idea (that's not new) to help people who have never performed fuzz testing begin fuzz testing with very little cost and friction. The idea is to add a small layer of code to an application to automatically mutate untrusted data as it comes into an application; I called that code layer "a layer of hurt."

Before I continue, I want to point out that fuzzing is an SDL requirement, but the idea in this blog post is not an SDL requirement, it's just another way to help meet SDL fuzzing requirements.

Adding a layer of hurt, as shown in the picture below, is pretty simple as it involves adding code to an application to tweak data as it comes into an application. You can work out where to place the fuzzing code by looking at your threat models to see where data crosses trust boundaries. You could also simply grep the code looking for APIs that read data, for example:

• Read from files: fread, ReadFile
• Reading from sockets: recv, recvfrom
• For .NET code, any stream.Read

You get the picture.

The fuzzing code should appear right after the API that reads that data.

For example, C or C++ code that reads from a UDP socket and then fuzzes the data before it's consumed by the rest of the application might look like this:

Or, in C#, code that reads from an untrusted file:

In both code examples, Fuzz() mutates the incoming data. In the C++ case, the fuzzing code looks like this:

The sample C# and C++ fuzzing code is available as a ZIP file at the end of this post.

This code is an example of dumb-fuzzing, which is fuzzing with little or no regard for the data structure being manipulated. If you've never performed any kind of fuzz testing in the past, then you will probably find bugs with this simple fuzzing technique. Once you have weeded out the low-hanging bugs, you may need to turn your attention to smarter fuzzers. For example, in theory, this code would find few if any bugs in a PNG parser, because PNG files have a built in check-sum, so if you fuzz a PNG file, you'd have to recalculate the checksum to get decent code coverage.

When I showed this code during my presentation, I urged people to add it to their applications today if they currently don't do fuzz testing, and simply run their applications through their normal testing processes. Within three days of my presentation I received emails from people saying they had found bugs. I have no doubt others did too.

One of the comments I made during the session was,"If you can't spend the time on great fuzzing, fuzz anyway" and adding a "layer of hurt" is a reasonable start.

Please feel free to sound off if you have ideas to help improve the code and let us know what you think, either through email or comments to this post.