Quote from: JorgeStolfi on August 19, 2014, 09:38:42 PM

Quote from: souspeed on August 19, 2014, 04:36:11 PM

Quote from: JorgeStolfi on August 19, 2014, 04:19:32 PM

Quote from: gmannn on August 19, 2014, 03:39:47 PM

Quote from: truthstalker on August 19, 2014, 03:19:43 PM

Is this just as secure as a paper wallet? I should imagine it isn't because it requires you the manufacturer to actually have access to the private keys?

The keys are generated using entropy from the trezor plus entropy from the computer you plug into. There's no way for the manufacturer to know your keys.

Well, if the manufacturer of a hardware wanted to get the client's keys, they could do it very easily.
If you use a special-purpose hardware to store your keys, you have to trust the manufacturer. I see no way around it.

The hardware can be checked and the software is open source.

Checking the hardware is viable only with sophisticated lab equipment. To check the software, someone whould have to carefully check the source code (at every release) for malicious backdoors or weaknesses, and then the client would have to check that the compiled firmware that he is loading, duly signed by the manufacturer, matches that source code. Obviously neither is viable in practice, except after the fact.

Back to the original question:
"Is this just as secure as a paper wallet?" No. It cannot be. However it's much more useful, because from this wallet you can actually spend. It's also very easy to use. Creating a really secure paper wallet is difficult. Setting up and using Trezor is easy.

"requires you the manufacturer to actually have access to the private keys" This statement is dead wrong. In many services out there, the main premise is that end user cannot keep his private keys secure, thus he should keep it with some online service that will take care of security. This creates just another issue for the user, because he now has to keep his service credentials secure and he has to trust the service provider so he is in even more difficult situation. Trezor is different. It lets you own your private keys without manufacturer knowing anything about you. In theory, Satoshi Labs can recover your seed from the device if the device is still working and they have physical access to it. But that is only if you are not using passphrases and give them the device and they actually want to recover your seed.

Without the physical access to the hardware, there is only a single way manufacturer could get your keys: backdoor. There is a catch though. If your bitcoins are stolen by a malware or a hacker, then you are just screwed. If your btc is stolen by an open software, open hardware backdoored device, then you can sue somebody. I assume their liability for a software bug is at the zero level. Their liability for a money stealing backdoors is a complete different story. That is fraud and you can sue it everywhere in the world.

Also, your statement that checking the software is not viable in practice is wrong. They use deterministic build so everybody can check that the software is what it is supposed to be. Also, the software is single purpose, thus small, thus verifiable for backdoors.