Friday Squid Blogging: Kim Jong Un Tours Frozen Squid Factory
Frozen squid makes him happy.
As usual, you can also use this squid post to talk about the security stories in the news that I haven’t covered.
Page 439
Operation Vula
“Talking to Vula” is the story of a 1980s secret communications channel between black South African leaders and others living in exile in the UK. The system used encrypted text encoded into DTMF “touch tones” and transmitted from pay phones.
Our next project was one that led to the breakthrough we had been waiting for. We had received a request, as members of the Technical Committee, to find a way for activists to contact each other safely in an urban environment. Ronnie had seen a paging device that could be used between users of walkie-talkies. A numeric keypad was attached to the front of each radio set and when a particular number was pressed a light would flash on the remote set that corresponded to the number. The recipient of the paging signal could then respond to the caller using a pre-determined frequency so that the other users would not know about it.
Since the numbers on the keypad actually generated the same tones as those of a touch-tone telephone it occurred to us that instead of merely having a flashing light at the recipient`s end you could have a number appear corresponding to the number pressed on the keypad. If you could have one number appear you could have all numbers appear and in this way send a coded message. If the enemy was monitoring the airwaves all they would hear was a series of tones that would mean nothing.
Taking this a step further we realised that if you could send the tones by radio then they could also be sent by telephone, especially as the tones were intended for use on telephone systems. Ronnie put together a little microphone device that – when held on the earpiece of the receiving telephone – could display whatever number was pressed at the sending end. Using touch-tone telephones or separate tone pads as used for telephone banking services two people could send each other coded messages over the telephone. This could be done from public telephones, thus ensuring the safety of the users.
To avoid having to key in the numbers while in a telephone booth the tones could be recorded on a tape recorder at home and then played into the telephone. Similarly, at the receiving end, the tones could be recorded on a tape recorder and then decoded later. Messages could even be sent to an answering machine and picked up from an answering machine if left as the outgoing message.
We gave a few of these devices, disguised as electronic calculators, to activists to take back to South Africa. They were not immensely successful as the coding still had to be done by hand and that remained the chief factor discouraging people from communicating.
The next step was an attempt to marry the tone communication system with computer encryption. Ronnie got one of the boffins at the polytechnic to construct a device that produced the telephone tones at very high speed. This was attached to a computer that did the encryption. The computer, through the device, output the encrypted message as a series of tones and these could be saved on a cassette tape recorder that could be taken to a public telephone. This seemed to solve the problem of underground communications as everything could be done from public telephones and the encryption was done by computer.
Lots more operational details in the article.
Report on Syrian Malware
Fascinating report from Citizen Lab on the use of malware in the current Syrian conflict (EFF summary and Wired article).
NSA Spying: Whom Do You Believe?
On Friday, Reuters reported that RSA entered into a secret contract to make DUAL_EC_PRNG the default random number generator in the BSAFE toolkit. DUA_EC_PRNG is now known to have been backdoored by the NSA.
Yesterday, RSA denied it:
Recent press coverage has asserted that RSA entered into a “secret contract” with the NSA to incorporate a known flawed random number generator into its BSAFE encryption libraries. We categorically deny this allegation.
[…]
We made the decision to use Dual EC DRBG as the default in BSAFE toolkits in 2004, in the context of an industry-wide effort to develop newer, stronger methods of encryption. At that time, the NSA had a trusted role in the community-wide effort to strengthen, not weaken, encryption.
We know from both Mark Klein and Edward Snowden—and pretty much everything else about the NSA—that the NSA directly taps the trunk lines of AT&T (and pretty much every other telcom carrier). On Friday, AT&T denied that:
In its statement, AT&T sought to push back against the notion that it provides the government with such access. “We do not allow any government agency to connect directly to our network to gather, review or retrieve our customers’ information,” said Watts.
I’ve written before about how the NSA has corroded our trust in the Internet and communications technologies. The debates over these companies’ statements, and about exactly how they are using and abusing individual words to lie while claiming they are not lying, is a manifestation of that.
Me again:
This sort of thing can destroy our country. Trust is essential in our society. And if we can’t trust either our government or the corporations that have intimate access into so much of our lives, society suffers. Study after study demonstrates the value of living in a high-trust society and the costs of living in a low-trust one.
Rebuilding trust is not easy, as anyone who has betrayed or been betrayed by a friend or lover knows, but the path involves transparency, oversight and accountability. Transparency first involves coming clean. Not a little bit at a time, not only when you have to, but complete disclosure about everything. Then it involves continuing disclosure. No more secret rulings by secret courts about secret laws. No more secret programs whose costs and benefits remain hidden.
Oversight involves meaningful constraints on the NSA, the FBI and others. This will be a combination of things: a court system that acts as a third-party advocate for the rule of law rather than a rubber-stamp organization, a legislature that understands what these organizations are doing and regularly debates requests for increased power, and vibrant public-sector watchdog groups that analyze and debate the government’s actions.
Accountability means that those who break the law, lie to Congress or deceive the American people are held accountable. The NSA has gone rogue, and while it’s probably not possible to prosecute people for what they did under the enormous veil of secrecy it currently enjoys, we need to make it clear that this behavior will not be tolerated in the future. Accountability also means voting, which means voters need to know what our leaders are doing in our name.
This is the only way we can restore trust. A market economy doesn’t work unless consumers can make intelligent buying decisions based on accurate product information. That’s why we have agencies like the FDA, truth-in-packaging laws and prohibitions against false advertising.
We no longer know whom to trust. This is the greatest damage the NSA has done to the Internet, and will be the hardest to fix.
EDITED TO ADD (12/23): The requested removal of an NSA employee from an IETF group co-chairmanship is another manifestation of this mistrust.
Friday Squid Blogging: "What Does the Squid Say?"
Minecraft parody.
As usual, you can also use this squid post to talk about the security stories in the news that I haven’t covered.
Yes, I'm Leaving BT
The Register reported that I am leaving BT at the end of the year. It quoted BT as saying:
We hired Bruce because of his thought leadership in security and as part of our acquisition of Counterpane. We have agreed to part ways as we felt our relationship had run its course and come to a natural end. It has nothing to do with his recent blogs. We hired Bruce because of his thought leadership in security, not because we agree with everything he says. In fact, it’s his ability to challenge our assumptions that made him especially valuable to BT.
Yes, it’s true. And contrary to rumors, this has nothing to do with the NSA or GCHQ. No, BT wasn’t always happy with my writings on the topic, but it knew that I am an independent thinker and didn’t try to muzzle me in any way. I’m just ready to leave. I spent seven years at BT, and seven years at Counterpane Internet Security, Inc., before BT bought us. It’s past time for something new.
As to what comes next: answer cloudy; ask again later.
More news here. And a Slashdot and Hacker News thread.
Eben Moglen and I Talk about the NSA
Last week, Eben Moglen and I had a conversation about NSA surveillance. Audio and video are online.
EDITED TO ADD: The site seems to be down, so here’s a YouTube link.
Acoustic Cryptanalysis
This is neat:
Here, we describe a new acoustic cryptanalysis key extraction attack, applicable to GnuPG’s current implementation of RSA. The attack can extract full 4096-bit RSA decryption keys from laptop computers (of various models), within an hour, using the sound generated by the computer during the decryption of some chosen ciphertexts. We experimentally demonstrate that such attacks can be carried out, using either a plain mobile phone placed next to the computer, or a more sensitive microphone placed 4 meters away.
Beyond acoustics, we demonstrate that a similar low-bandwidth attack can be performed by measuring the electric potential of a computer chassis. A suitably-equipped attacker need merely touch the target computer with his bare hand, or get the required leakage information from the ground wires at the remote end of VGA, USB or Ethernet cables.
Tor User Identified by FBI
Eldo Kim sent an e-mail bomb threat to Harvard so he could skip a final exam. (It’s just a coincidence that I was on the Harvard campus that day.) Even though he used an anonymous account and Tor, the FBI identified him. Reading the criminal complaint, it seems that the FBI got itself a list of Harvard users that accessed the Tor network, and went through them one by one to find the one who sent the threat.
This is one of the problems of using a rare security tool. The very thing that gives you plausible deniability also makes you the most likely suspect. The FBI didn’t have to break Tor; they just used conventional police mechanisms to get Kim to confess.
Tor didn’t break; Kim did.
Sidebar photo of Bruce Schneier by Joe MacInnis.