Dumb gaming "news" YouTube channels (hi MVG): "omg...

Dumb gaming "news" YouTube channels (hi MVG): "omg @dolphin devs are so dumb for distributing decryption keys everyone else does things differently"

PPSSPP: https://github.com/hrydgard/ppsspp/blob/master/Core/ELF/PrxDecrypter.cpp#L20
RPCS3: https://github.com/RPCS3/rpcs3/blob/master/rpcs3/Crypto/key_vault.cpp#L25
Xenia: https://github.com/xenia-project/xenia/blob/master/src/xenia/kernel/xboxkrnl/xboxkrnl_crypt.cc#L608
Cemu: https://github.com/cemu-project/Cemu/blob/master/src/Cemu/ncrypto/ncrypto.cpp#L340
Citra: https://github.com/citra-emu/citra/blob/master/src/core/hw/aes/key.cpp#L36
Desmume: https://github.com/TASEmulators/desmume/blob/master/desmume/src/utils/decrypt/decrypt.cpp#L33

I think of all the emulators I've checked for platforms that use crypto for DRM/obfu, Yuzu are the only ones not shipping keys.

Like 4 Jun 2023 at 10:19 | Open on mastodon.delroth.net

21 comments

Dragoon Aethis

@delroth Ryujinx also wants you to bring your own keys :D

4 Jun 2023 at 10:22 | Open on mstdn.social

Pierre Bourdon

@dragoonaethis what about these? https://github.com/Thealexbarney/LibHac/blob/master/build/CodeGen/IncludedKeys.txt

4 Jun 2023 at 10:29 | Open on mastodon.delroth.net

Dragoon Aethis

@delroth Welp, I get to eat my words then.

4 Jun 2023 at 11:03 | Open on mstdn.social

13xforever

@dragoonaethis @delroth they're using LibHac, which comes with default keys.

Pretty sure Ryujinx is also outsourcing some default keys.

After PS2 era it's literally impossible to emulate systems without including some kind of common key for crypto.

4 Jun 2023 at 10:39 | Open on social.treehouse.systems

Pierre Bourdon

@13xforever @dragoonaethis arguably even PS2 era -- GameCube comes with some DRM crypto already, just not for games. They have some fancy obfuscation using custom code running on the DSP to do challenge/response auth with memory cards and GBA link cable.

https://github.com/dolphin-emu/dolphin/blob/master/Source/Core/Core/HW/DSPHLE/UCodes/GBA.cpp#L64

Luckily Dolphin doesn't have to emulate the memory card one since they can bypass the DRM altogether with emulated memory cards :)

4 Jun 2023 at 11:15 | Open on mastodon.delroth.net

Emma (IPG)

@delroth in a fair amount of these cases it's impossible to dump these keys clean room... which is concerning if this move sets precedent

(i know this doesn't make the point you're making any less valid, but i am big into 360 stuff so a very minor nitpick, the key you linked on xenia is the roamable obfuscation key used for very little and most games will work without :P

the retail xex2 key however... https://github.com/xenia-project/xenia/blob/master/src/xenia/cpu/xex_module.cc#L32 )

4 Jun 2023 at 10:28 | Open on wetdry.world

Rairii

@ipg @delroth "impossible to dump these keys clean room"

it doesn't matter. technically just reimplementing the crypto on its own (without the keys) is a DMCA 1201 violation

4 Jun 2023 at 10:30 | Open on haqueers.com

Pierre Bourdon

@Rairii @ipg it's part of what's required for a DMCA 1201 violations*

But yeah, that's why I'm facepalming very hard at everyone focusing on the presence or absence of keys. Literally doesn't matter as long as you have the code there to decrypt copy-protected content.

4 Jun 2023 at 10:32 | Open on mastodon.delroth.net

Haelwenn /элвэн/ :triskell:

@Rairii @ipg @delroth Forgot what VLC ended up doing for DeCSS but wouldn't be surprised that they just include the key, because France/Europe has more sane laws.

4 Jun 2023 at 10:34 | Open on queer.hacktivis.me

Pierre Bourdon

@ipg thanks, let me fix the link. It indeed doesn't change my point :-)

4 Jun 2023 at 10:30 | Open on mastodon.delroth.net

Charlotte 🦝 θΔ

@delroth @dolphin Not an encryption key, but every SNES emulator i have seen is shipping the bootstrap rom of the SPC700

4 Jun 2023 at 10:31 | Open on akko.chir.rs

*Ada :collar: 🇦🇶

@delroth @dolphin it also is common for custom firmware to have main/common keys.

4 Jun 2023 at 10:32 | Open on tech.lgbt

Leonie :vf:

@delroth and the thing is it's perfectly legal to distribute those keys. Apple tried to keep their keys to boot macOS as a trade secret, but lost in court and their keys are even publicly available: https://www.rcfp.org/wp-content/uploads/imported/20120105_202426_apple_sealing.pdf. The argument that distributing keys to decrypt software is illegal has long been proven a myth. Nintendo had no right to tell Steam to pull Dolphin off the store.

4 Jun 2023 at 10:34 | Open on cutebox.cc

asie

@delroth@mastodon.delroth.net DesMuME's key inclusion strikes me particularly odd, as you really don't need secure area decryption in the emulator itself for most use-cases - given that melonDS only ships decryption keys for its DSi mode, I'd assume DraStic (which doesn't support DSi mode) does not ship any keys; and given NO$GBA's extensive documentation on how to dump the DSi-mode keys, that one might not be shipping any at all either...

4 Jun 2023 at 10:36 | Open on mk.asie.pl

mofu mofu fumo

@delroth @dolphin this level of discourse from "the gamers" about dolphin shipping keys being stupid (like every other project in the space minus switch emu who'd get smacked past saturn if they did so) is why i dont blame nintendo and the rest of the video game industry for hating thier users so much.

4 Jun 2023 at 10:58 | Open on federated.fun

Pierre Bourdon

Adding a few more mentioned in the replies:

Vita3k: https://github.com/Vita3K/Vita3K/blob/master/vita3k/packages/src/sce_utils.cpp#L39
Ryujinx: https://github.com/Thealexbarney/LibHac/blob/master/build/CodeGen/IncludedKeys.txt
melonDS: https://github.com/melonDS-emu/melonDS/blob/master/src/DSi_AES.cpp#L141
no$gba: not open source, you can compare https://gist.github.com/delroth/4fb0528a2306147a38a89817c3ef304c from a quick disasm with melonDS above