Kernel Trap Interview with Theo de Raadt

An anonymous reader writes "KernelTrap has an insightful interview with Theo de Raadt, creator of OpenBSD. The wide-ranging interview focuses first on the past few years of OpenBSD development, then moves on to the recently released OpenBSD 3.9. De Raadt talks about how binary blobs threaten free software, and how OpenBSD developers work to reverse engineer them. He also talks about the future of OpenBSD, his views on Linux, and why developing truly free software is so important to him."

Comments

Theo

[Anonymous Coward]

Weird... was Theo having a bad day? He's always seemed like such a nice guy, but in this interview he really comes off like a total a-hole... very un-Theo-ish.

FCC Rules

[jusdisgi]

I sure wish he had taken a better position on the wifi "FCC Rules require Binary Blobs" issue. He basically agreed that the FCC does require that the consumer not be able to change the frequency, but claimed that it should be dealt with in hardware, not the driver. This line is particularly poorly thought out: "Let the FCC go after the vendors who made the flawed devices."

See, here's the thing...the people he needs to convince here are the hardware manufacturers. You aren't going to get them to release open drivers by suggesting that the FCC should "go after" them. In fact, it serves to reinforce their binary-blobs-only position; after all, that's their current protection. But worse, by tacitly agreeing with their position about the FCC rules, he cedes the important part of the argument...the part where he could have won it. That's because while the FCC does indeed require that the consumer not be able to change the frequency to licensed spectrum, they have never taken the position that changing the source code is normal consumer operation. After all, consumers can change the frequency on many other chipsets (even in Windows) with binary patches. This is simpler than changing source code and recompiling it. I have never heard anything from the FCC that says you can't distribute source code with this functionality. Which is good, because the current mainline Linux kernel does distribute code that does this. If FCC rules actually forbade this (as the hardware companies are claiming) then it would be illegal to distribute the Linux (and presumably OpenBSD) kernel in the USA.

There was a wonderful discussion of this on the LKML recently in context of Intel's binary blob driver.

Re:FCC Rules

[TigerNut]

As a current and past employee of several companies that make wireless transceivers subject to FCC licensing, I can tell you that there is no cost effective way to limit a device to FCC restrictions purely in hardware. Example: A cellular radio or any other modern RF link uses a synthesizer to set the transmit frequency. The output frequency of the synthesizer is a function of the reference frequency and the programmed divide ratio, and the total span of achievable output frequencies is dependent on the VCO that the synth is controlling. The maker of the synthesizer is not usually in a position to dictate the exact reference frequency, nor the VCO that it's hooked up to. The VCO vendor doesn't dictate the type of system that it will be installed into, and therefore can't strictly limit the frequency that it will tune to - and even if they did know exactly where it was going to go, then production tolerances dictate that you have some tuning margin in the design to allow all parts to hit the specified span. That means that individual parts will be tunable outside of the specified span on either the high or low side, and if the micro that controls the synthesizer commands a frequency outside the FCC limits, a lot of the time the hardware will have no problem doing it.

The same thing applies generally to power output levels. Sophisticated radios have some spare margin in the transmitter power output, and the actual output power level is calibrated at manufacturing time and then set in a FLASH based lookup table. The output power is then controlled using the embedded micro, driving a DAC. In this system, having open code on the embedded micro means that an uncaring individual could just crank the power output without regard for the FCC requirements.

You can say what you want about the motivations and ethics of the OpenBSD team members - if the source is out there, there will be others that take advantage of any "gains" they could make by tweaking some tuning parameters beyond the design or regulatory limits.

Ask Theo de Raadt how long it took him to get from his buffer-overrun Sun console hacking days to where he is now - almost everyone goes through a phase where "Just because I can" is sufficient justification to do poorly thought out things.