The FBI has released updated Distributed Denial of Service detection tools for Linux and Solaris, and is urging people to use them - but the Feds are declining to make the source available. This is obviously a bit of a no-no for the open source audience you'd expect for Linux tools, and the stance looks even odder when you learn that the FBI's developer, Dave Dittrich of the University of Washington, has released his own software, with source. The FBI is making the tools, designed to detect TRINOO and Tribal Flood Network (TFN) attacks, available via the National Infrastructure Protection Center (NIPC). It does however seem to be refusing to release source as a matter of policy. Contacted by a Register reader the NIPC responded (corporately, apparently, as no spokesperson name was attached): "The NIPC has determined that it is important not to release the source code publicly. We do, however, have measures in place to help ensure that the executable on our website is not compromised. Thank you for contacting us." Our informant had pointed out that: "Many internet sites will *not* install binaries provided by the US government, and specifically the FBI, lacking source. I would strongly recommend that you provide source for these tools, preferably under an OSI compliant license (GPL, BSD, MozPL, etc.), at the very least simply publishing source whether or not you allow modifications of it, though copyright in government works is not, AFAIK, applicable in this case." This seems to be a mindset too far for the NIPC. But never mind, although the FBI version isn't likely to be that popular, Dittrich's version comes with source. We're told that the FBI version runs on the target systems and searches files for traces of the DDOS tools, whereas version with source attempts to remotely identify the DDOS tools by eliciting certain responses to network probes. According to our informant (thanks, reader): "This method is much less reliable as it typically relies on the tools having the original passwords. However, running programs on the target systems is much harder to automate." So there you go. Pays your money (not exactly), takes your choice. ® Your DDOS downloads tonight: FBI version Dittrich implementation