I get error 31020 with Solatorobo when I try to download DLC same with Layton
There is no DLC, just Pokemon Mystery Gift and not for all games.
Homebrew nds-constrain't - Taking advantage of a flaw in the Nintendo DS(i) SSL library
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There is no DLC, just Pokemon Mystery Gift and not for all games.
There is a writeup of it all on
https://github.com/KaeruTeam/nds-constraint
In this case it is more that owing to a shoddy implementation of SSL on the DS we could use another key Nintendo signed for another purpose but have the have the DS think it is an acceptable substitution.
Looks like it's using SHA-1. IIRC it's now possible to produce collisions with this hash. Wouldn't this have been just as good for producing user certs whose hash matches that of another Nintendo-signed cert? No trust chain flaw required.
I have not kept up with SHA1 stuff lately to see if complexity has been reduced further but the amount of computing power required for such a trick when the hashes were revealed back in 2017 was quite considerable (industrial espionage/nation state level, and last month https://www.schneier.com/blog/archives/2018/12/md5_and_sha-1_s.html reckons a preimage attack is still not on the cards). If we have suitable certs and keys and every game out there does not check the flag mentioned in the writeup then why bother forcing a hash? Even more so if a simple game mod (or even cheat) can also do the same thing?
Ah, thank you for the response. I skimmed the github readme earlier and didn't retain anything about the keys.
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You know another thing that uses SHA-1? The decrypted RSA block of SRL files...Someone correct me if I'm wrong here, but as I recall the main way SRLs are authenticated (the header region specifically) is by decrypting the RSA region and comparing the SHA-1 value against a fixed region of the header area of the SRL. If the collision could be made to work on that SHA-1 hash then you could produce a modified SRL header that matches the original SHA-1?
Because with the way RSA works in this instance is that it's used to encrypt the region that the SHA-1 hash is stored. There is a public key used to decrypt it and a private key used to encrypt it. We can't encrypt because no private key and thus can't change the SHA-1 hash.
But I'm pretty sure getting public key is easy. Just pull that out of Launcher SRL as I'm sure it has to have it to decrypt SRL RSA regions. If you can manage to make a colliding SHA-1 you won't have to change the SHA-1 in the original RSA region, thus not needing to worry about re-encrypting it? Might be best to try and produce a colliding sha-1 of Launcher.
The main issue is TMD files though. You'd also have to break SHA-1 in those and I'm not sure if their RSA region is used in the same way...
Though as I recall TMDs have a SHA-1 for the entire SRL and that's how the TMD makes sure the SRL is the same. Could just collide that SHA-1 hash too with random data outside of the SRL header region. Since the RSA region only protects the DSi Extended header + NTR header of the SRL, data placed outside that can be used to make a colliding SHA-1 for the TMD? I think that could work.
The main issue though is entry point. We already have Unlaunch so there's no point doing this unless you can produce such a collision with a exported SRL via Data Management and make it easy for users to install Unlaunch on any DSi. I don't recall how the exported games are protected. As i recall it was easy to break and modify the save file stored in it for installing sudokuhax. If one could change the save, then one could change the SRL too? Later versions of Launcher fixed this attack point, but that shouldn't matter if you replace the SRL too and not worry about the save file. I think the main thing though is Launcher info in the ticket for the game to verify the content of the exported file. Haven't messed with these files that much so not sure on that one.
Oh also pretty sure 3DS related software uses SHA-256 and higher. Don't recall seeing much SHA-1 stuff there.
Because with the way RSA works in this instance is that it's used to encrypt the region that the SHA-1 hash is stored. There is a public key used to decrypt it and a private key used to encrypt it. We can't encrypt because no private key and thus can't change the SHA-1 hash.
But I'm pretty sure getting public key is easy. Just pull that out of Launcher SRL as I'm sure it has to have it to decrypt SRL RSA regions. If you can manage to make a colliding SHA-1 you won't have to change the SHA-1 in the original RSA region, thus not needing to worry about re-encrypting it? Might be best to try and produce a colliding sha-1 of Launcher.
The main issue is TMD files though. You'd also have to break SHA-1 in those and I'm not sure if their RSA region is used in the same way...
Though as I recall TMDs have a SHA-1 for the entire SRL and that's how the TMD makes sure the SRL is the same. Could just collide that SHA-1 hash too with random data outside of the SRL header region. Since the RSA region only protects the DSi Extended header + NTR header of the SRL, data placed outside that can be used to make a colliding SHA-1 for the TMD? I think that could work.
The main issue though is entry point. We already have Unlaunch so there's no point doing this unless you can produce such a collision with a exported SRL via Data Management and make it easy for users to install Unlaunch on any DSi. I don't recall how the exported games are protected. As i recall it was easy to break and modify the save file stored in it for installing sudokuhax. If one could change the save, then one could change the SRL too? Later versions of Launcher fixed this attack point, but that shouldn't matter if you replace the SRL too and not worry about the save file. I think the main thing though is Launcher info in the ticket for the game to verify the content of the exported file. Haven't messed with these files that much so not sure on that one.
Oh also pretty sure 3DS related software uses SHA-256 and higher. Don't recall seeing much SHA-1 stuff there.
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Is this still a thing or no? cause when i use the DNS it does not connect to anything
It work for some Pokemon games and Mario Kart. And try at a different time.
@ToxicXender Gen 4 Pokemon games have weirdly non-functioning connection tests but the Wi-Fi stuff works for some reason. Try going onto GTS or something and see if it works.
The best way to find out if it works or not is try using Mystery Gift since is way less picky that the GTS.
I have the same problem as the user here, I get error 31020 when trying to find downloads (DLC) with the DNS of altwfc in my dsi, is there any solution?
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