We will update the iOS app to offer you an option to point to your self hosted instance (so that you can save yourself the trouble of building it): https://github.com/ente-io/ente/discussions/504
Only the copyright holder(s) are able to grant Apple permission to distribute binaries of AGPL3-licensed software to iOS users under non-AGPL3 terms.
Every seemingly-(A)GPL3 app on Apple’s App Store has either copyright assignment so that a single entity has the sole right to distribute binaries in the App Store (eg, Signal messenger) or uses a modified license to carve out an Apple-specific exception to the anti-tivoization clause (eg, NextCloud). In my opinion, the first approach is faux free software, because anyone forking the software is not allowed to distribute it via the channel where the vast majority of users get their apps. (In either case, users aren’t allowed to run their own modified versions themselves without agreeing to additional terms from Apple, which is part of what the anti-tivoization clause is meant to prevent.)
Only really nice when not CLA is required and every contributor retains their copyright. Ente doesn’t seem to require a CLA.
I definitely agree here! But if it’s true that they’re accepting contributions without a CLA, and they haven’t added any iOS exception to their AGPL3 license, then they themselves would not be allowed to ship their own iOS app with 3rd party contributions to it! 😱 edit: it’s possible this is the case and Apple just hasn’t noticed yet, but that is not a sustainable situation if so.
If anyone reading this uses this software, especially on iOS, I highly recommend that you send the developers a link to this comment and encourage them to (after getting the consent of all copyright holders) add something akin to NextCloud’s COPYING.iOS to their repository ASAP.
edit: in case a dev actually sees this… skimming your architecture document it looks like when a user’s email is compromised (“after you successfully verify your email”), the attacker is given the encryptedMasterKey (encrypted with keyEncryptionKey, which is derived from a passphrase) which lets them perform an offline brute-force attack on the passphrase. Wouldn’t it make more sense to require the user to demonstrate knowledge of their passphrase to the server prior to giving them the encryptedMasterKey? For instance, when deriving keyEncryptionKey, you could also derive another value which is stored on the server and which the client must present prior to receiving their encryptedMasterKey. The server has the opportunity to do offline attacks on the passphrase either way, so it seems like there wouldn’t be a downside to this change. tldr: you shouldn’t let adversaries who have compromised a user’s email account have the ability to attack the passphrase offline.
(i’m not a cryptographer, but this is cryptography advice)
That’s complicated to do correctly. Normally, for the server to verify the user has the correct password, it needs to know or receive the password, at which point it could decrypt all the user’s files. They’d need to implement something like SRP.
Update: I contacted the developers to bring my comment to their attention and it turns out they have already implemented SRP to address this problem (but they haven’t updated their architecture document about it yet).
edit: the two issues i raised in this comment had both already been addressed.
this was the developer’s reply on matrix:
here is my original comment
This would be nice, but, this repo includes an iOS app, and AGPL3 binaries cannot be distributed via Apple’s App Store!
AGPL3 (without a special exception for Apple, like NextCloud’s iOS app has) is incompatible with iOS due to the four paragraphs of the license which mention “Installation Information” (known as the anti-tivoization clause).
Only the copyright holder(s) are able to grant Apple permission to distribute binaries of AGPL3-licensed software to iOS users under non-AGPL3 terms.
Every seemingly-(A)GPL3 app on Apple’s App Store has either copyright assignment so that a single entity has the sole right to distribute binaries in the App Store (eg, Signal messenger) or uses a modified license to carve out an Apple-specific exception to the anti-tivoization clause (eg, NextCloud). In my opinion, the first approach is faux free software, because anyone forking the software is not allowed to distribute it via the channel where the vast majority of users get their apps. (In either case, users aren’t allowed to run their own modified versions themselves without agreeing to additional terms from Apple, which is part of what the anti-tivoization clause is meant to prevent.)
I definitely agree here! But if it’s true that they’re accepting contributions without a CLA, and they haven’t added any iOS exception to their AGPL3 license, then they themselves would not be allowed to ship their own iOS app with 3rd party contributions to it! 😱 edit: it’s possible this is the case and Apple just hasn’t noticed yet, but that is not a sustainable situation if so.
If anyone reading this uses this software, especially on iOS, I highly recommend that you send the developers a link to this comment and encourage them to (after getting the consent of all copyright holders) add something akin to NextCloud’s COPYING.iOS to their repository ASAP.
cc @ioslife@lemmy.ml @baduhai@sopuli.xyz @skariko@feddit.it
(i’m not a lawyer, this is not legal advice, lol)
edit: in case a dev actually sees this… skimming your architecture document it looks like when a user’s email is compromised (“after you successfully verify your email”), the attacker is given the
encryptedMasterKey(encrypted withkeyEncryptionKey, which is derived from a passphrase) which lets them perform an offline brute-force attack on the passphrase. Wouldn’t it make more sense to require the user to demonstrate knowledge of their passphrase to the server prior to giving them theencryptedMasterKey? For instance, when derivingkeyEncryptionKey, you could also derive another value which is stored on the server and which the client must present prior to receiving theirencryptedMasterKey. The server has the opportunity to do offline attacks on the passphrase either way, so it seems like there wouldn’t be a downside to this change. tldr: you shouldn’t let adversaries who have compromised a user’s email account have the ability to attack the passphrase offline.(i’m not a cryptographer, but this is cryptography advice)
That’s complicated to do correctly. Normally, for the server to verify the user has the correct password, it needs to know or receive the password, at which point it could decrypt all the user’s files. They’d need to implement something like SRP.
Update: I contacted the developers to bring my comment to their attention and it turns out they have already implemented SRP to address this problem (but they haven’t updated their architecture document about it yet).