3 ms·

Why would I want to use this over chacha20 seeded properly?

by detrino 11y ago

aaron695 11y ago
It's more fun this way. Other than that you wouldn't. I guess you could argue governments all over the world are looking at chacha20, where as this has security through obscurity, which has value. But on the other side being handmade hardware it'd be much more likely to have flaws which analysis of the data might find rather quickly.
kaoD 11y ago
Well, since you need true randomness to seed ChaCha20 properly you could use this gadget to add more entropy to your pool. Of course if you really cared you'd just buy a real TRNG.
- vog 11y ago
  > you'd just buy a real TRNG But then you have a blackbox and are forced to trust the manufacturer. (And as the Snowden revelations show, you have to care about man-in-the-middle attacks over the postal system, while that blackbox is on the way to you.) To add some tinfoil-hat mentality on top of that: I believe it is easier to manipulate a blackbox TRNG than it is to manipulate individual components (transistors, etc.). So although the DIY approach has the downside that you may get things wrong, it has the upside that it is very hard to manipulate.
JoachimS 11y ago
The Cryptech TRNG uses ChaCha as CSPRNG. ChaCha is seeded using two separate noise sources of which one is based on the same principle as the one described in the article. The output from the entropy sources are mixed using SHA-512 before being used to seed ChaCha. The Cryptech TRNG has been and is continiously tested. The current development will add test functionality to provide online monitoring of the entropy sources as well as the final output from ChaCha. There will also be a specific test mode to allow user applications to insert its own "entropy" and extract generated seed as well as providing test vectors for ChaCha. In this way it will be possible to verify that the TRNG works during production, but also verify that the digital chain is in fact working as specified. For more see: http://wiki.cryptech.is/wiki http://wiki.cryptech.is/wiki (Disclaimer: I am the main author of the Cryptech TRNG.)
- detrino 11y ago
  Is gathering 256 bits of entropy a problem that justifies a dedicated piece of hardware?

Why would I want to use this over chacha20 seeded properly?

by detrino 11y ago

Why would I want to use this over chacha20 seeded properly?

It's more fun this way. Other than that you wouldn't. I guess you could argue governments all over the world are looking at chacha20, where as this has security through obscurity, which has value. But on the other side being handmade hardware it'd be much more likely to have flaws which analysis of the data might find rather quickly.

kaoD 11y ago

Well, since you need true randomness to seed ChaCha20 properly you could use this gadget to add more entropy to your pool. Of course if you really cared you'd just buy a real TRNG.

vog 11y ago
> you'd just buy a real TRNG But then you have a blackbox and are forced to trust the manufacturer. (And as the Snowden revelations show, you have to care about man-in-the-middle attacks over the postal system, while that blackbox is on the way to you.) To add some tinfoil-hat mentality on top of that: I believe it is easier to manipulate a blackbox TRNG than it is to manipulate individual components (transistors, etc.). So although the DIY approach has the downside that you may get things wrong, it has the upside that it is very hard to manipulate.

JoachimS 11y ago

The Cryptech TRNG uses ChaCha as CSPRNG. ChaCha is seeded using two separate noise sources of which one is based on the same principle as the one described in the article. The output from the entropy sources are mixed using SHA-512 before being used to seed ChaCha. The Cryptech TRNG has been and is continiously tested. The current development will add test functionality to provide online monitoring of the entropy sources as well as the final output from ChaCha. There will also be a specific test mode to allow user applications to insert its own "entropy" and extract generated seed as well as providing test vectors for ChaCha. In this way it will be possible to verify that the TRNG works during production, but also verify that the digital chain is in fact working as specified. For more see: http://wiki.cryptech.is/wiki http://wiki.cryptech.is/wiki (Disclaimer: I am the main author of the Cryptech TRNG.)

detrino 11y ago
Is gathering 256 bits of entropy a problem that justifies a dedicated piece of hardware?