MSO2000 modules made right? How? - Page 1
Forum section: electronics / testgear

author: firewalker
author_rank: Super Contributor
timestamp: August 10, 2014, 04:31:05 pm
content: Given the opportunity formTHISthread. Hoe would you do it to avoid hacking?I don't really know much about methods around this matter.Asymmetric encryption communication with sudorandom public session keys?Alexander.

author: David Hess
author_rank: Super Contributor
timestamp: August 10, 2014, 05:10:31 pm
content: That is how I would do it; the test instrument generates a random number, sends it to the module which encrypts it with its private key, and then the test instrument decrypts the results with its public key and checks for a match. With different types of modules it would be a little more complicated but basically comes down to the same thing. Symmetrical encryption could be used with the risk of doubling the exposure of the key.The above relies on the private or symmetrical key remaining private but a hacker would either have to duplicate whatever processing the module does or just hack the test instrument itself. Either would be more complicated than just copying an EEPROM.If I were doing it cheaply, I would use a relatively secure but inexpensive standard microcontroller in the module.

author: SeanB
author_rank: Super Contributor
timestamp: August 10, 2014, 05:21:33 pm
content: You mean like these S Crypt encryption modules from a public phone? Looks like a standard SIM card but is an encryption engine inside.

author: David Hess
author_rank: Super Contributor
timestamp: August 10, 2014, 05:31:04 pm
content: I am sure those do something similar. Smart cards do as well.The risk of fraud is lower with test equipment so I doubt it is worthwhile to use something that complicated.

author: SeanB
author_rank: Super Contributor
timestamp: August 10, 2014, 06:03:20 pm
content: They were used at least one per payphone, and they were a lot more common than test equipment, so likely they definitely wanted good encryption as the loss of the key leads directly to a massive potential of fraudulent calls being made.

author: mamalala
author_rank: Unknown
timestamp: August 11, 2014, 09:54:01 am
content: There are smartcard-chips available that come in standard SO8 packages, for example the older SLE66C24PE.Greetings,Chris

author: amyk
author_rank: Super Contributor
timestamp: August 11, 2014, 10:40:15 am
content: Fancy checks with encryption between modules and firmware -> patch the firmwareFirmware checks itself -> patch the firmwareFirmware encrypted -> someone figures out decrypted version and patches itIf it can be used by someone it will be cracked.The (cr/h)ackers will always win.

author: David Hess
author_rank: Super Contributor
timestamp: August 11, 2014, 01:12:08 pm
content: I do not disagree amyk but it takes a lot more effort to do those things than to just copy an EEPROM.

author: poida_pie
author_rank: Regular Contributor
timestamp: August 12, 2014, 01:07:14 am
content: I agree with you amyk, just look at an excellent example fromhttps://www.eevblog.com/forum/testgear/sniffing-the-rigol%27s-internal-i2c-bus/hardware hacking, worked fine but you needed to open the box,then software, no need to open box, (decrypt work)now again need to open box to get key, for simple software keygen

author: Mark_O
author_rank: Frequent Contributor
timestamp: August 12, 2014, 08:02:59 am
content: Quote from: firewalker on August 10, 2014, 04:31:05 pmSeriously?Are wereallygoing to do the manufs job for them, and tell them how to make hacking harder for us?