Poor, Homegrown Encryption Threatens Open Smart Grid Protocol

An anonymous reader writes: Millions of smart meters, solar panels, and other grid-based devices rely on the Open smart grid protocol for communication and control — it's similar to SCADA's role for industrial systems. But new research shows that its creators made the common mistake of rolling their own encryption, and doing a poor job of it. The researchers believe this threatens the entire system. They say, "This function has been found to be extremely weak, and cannot be assumed to provide any authenticity guarantee whatsoever." Security analyst Adam Crain added, "Protocol designers should stick to known good algorithms or even the 'NIST-approved' short list. In this instance, the researchers analyzed the OMA digest function and found weaknesses in it. The weaknesses in it can be used to determine the private key in a very small number of trials."

Comments

Re:How many times do we have to say it?

[mlts]

Homegrown crypto has been a constant menace since the 1990s when people sold numerous encryption programs, usually sporting their own encryption algorithm and DES.

A few I've seen were running 1-2 rounds of DES at most (FWB Hammer's hard disk drivers for Macs did this, but at the time, it was the best encryption one could get due to the relatively slow CPUs like 68000s at the time.) Others were seeding random() with a CRC of the password and XORing the output with the plaintext.

However, back then, there were no government entities standardizing functions like is done now with AES, RSA, and other algos, so people had to write their own, and if it jumbled and unjumbled stuff, it was good enough, since not much in the way of ciphertext was really being attacked.

Times are different now.

These days, with most ARM, AMD, SPARC, POWER, and Intel CPUs having hardware AES acceleration, why would one want to roll their own algorithm?

If one thinks AES is backdoored, cascade it with another known good algorithm like SERPENT, Threefish, heck, maybe even an older one like IDEA, 3DES, or even 3-Skipjack. There are other less known algorithms which have withstood testing as well. Cascading isn't intended to expand the bit width, but to have protection should one algorithm get broken. TrueCrypt offers/offered this functionality.

Same with public key algorithms. Worried about RSA? Have two signatures, one RSA, and one with ECC or a lattice based algorithm that is resistant to TWIRL and quantum factoring, and validate both sigs.

As for crypto implementations, if a user needs to encrypt a file, OpenPGP is a known standard. For communicating across the wire, SSH and SSL are known standards that are decently robust. For encrypting stuff in RAM, almost all modern operating systems have a facility like KeyChain to keep sensitive data from being swapped out, or if it is, have it encrypted.

With almost every programming language offering hooks for AES and RSA, there isn't a need to roll crypto, even for obfuscation reasons. If one just needs obfuscation, use an AES() function with all zeroes as the key.

Re:How many times do we have to say it?

[PRMan]

Here is a link to the article: https://bitcoinmagazine.com/7781/satoshis-genius-unexpected-ways-in-which-bitcoin-dodged-some-cryptographic-bullet/