4 ms·

I like seafile too, but after doing some of my own review of the source (https://github.com/haiwen/seafile/issues/350 https://github.com/haiwen/seafile/issues/3

by ef4 12y ago

I like seafile too, but after doing some of my own review of the source (https://github.com/haiwen/seafile/issues/350 https://github.com/haiwen/seafile/issues/350) I'm not willing to trust it on the open internet. For now I run seafile inside a private network behind a vpn. But I'd rather find an alternative with a better security story. Something from a team that can justify their cryptographic constructs in detail.

lugg 12y ago
I dont get it, why is deduping at a chunk level important, can't it just take it as a tradeoff and dedupe at the file level, or does that have the same problems? And why exactly is deduping important for a personal use case, bandwidth is relatively cheap. In any case, while I want security in these systems to avoid mass survey style attacks, I assume anything I put over the wire to be compromised at least potentially. I keep the kind of files that need that level of encryption on encrypted flash drives.
- enscr 12y ago
  If you are encrypting each file individually, you are still giving away the file names. Hence you use encrypted file containers. They benefit from block level deduplication. They can be large in size.
  - icebraining 12y ago
    If you are encrypting each file individually, you are still giving away the file names. Hence you use encrypted file containers. That doesn't follow - you can solve the problem without containers, e.g. by encrypting or hashing the filenames. Containers protect the file sizes, but they lose the ability to selectively sync certain files to certain nodes.
    - enscr 12y ago
      Hashing doesn't solve the problem completely. You are still giving away information about file count, size & hierarchy. Regarding selective sync : you'll have to organize the files logically into containers. I think even Dropbox doesn't let you sync files selectively, you have to have content separated into folders. I'm not saying that one is better than other, just giving an example of where de-duping at block level is needed as @lugg asked.
      - icebraining 12y ago
        Hashing doesn't solve the problem completely. You are still giving away information about file count, size & hierarchy. Sure; I was just talking about the file names. You can avoid the hierarchy part by transmitting it separately from the files in a secure way, though. Regarding selective sync : you'll have to organize the files logically into containers. I think even Dropbox doesn't let you sync files selectively, you have to have content separated into folders. git-annex does. You can implement rules to decide what files should be synced, which should be dropped locally, etc. For example, an MP3 player running it might have a rule such as filename(*.mp3) or filename(*.ogg) and it'll only sync those files, regardless of their directories.
icebraining 12y ago
git-annex avoid all except (2), by simply encrypting each file using GnuPG, and applying an HMACSHA1 to the filenames. http://git-annex.branchable.com/encryption/ http://git-annex.branchable.com/encryption/
- stinos 12y ago
  no doubt it would be my first choice if it had proper windows support, but last time I checked that was still lacking
- higherpurpose 12y ago
  SHA1?
  - icebraining 12y ago
    It's configurable. The default MAC algorithm to be applied on the filenames is HMACSHA1. A stronger one, for instance HMACSHA512, one can be chosen upon creation of the special remote with the option mac=HMACSHA512. The available MAC algorithms are HMACSHA1, HMACSHA224, HMACSHA256, HMACSHA384, and HMACSHA512.
  - gioele 12y ago
    Don't worry, git-annex uses SHA1 just as a checksum, not for cryptographic purposes.
- berdario 12y ago
  I tried to use git annex assistant: I can get files to be backed-up on a server, but when doing sync between 2 different machines it has never worked (I've been doing the xmpp-setup dance multiple times, and it's especially painful due to having 2factor auth enabled on google) I'll have to try using plain git annex from the commandline to try to understand what is going wrong (I already used it to clean some repositories that the assistant was refusing to delete) PS: I tried it with 2 machines in the same LAN (both linux... though one of the 2 distros had a slightly older version of the git-annex package)
abus 12y ago
Are there any issues you suspect Syncthing could suffer from?

by ef4 12y ago

lugg 12y ago

I dont get it, why is deduping at a chunk level important, can't it just take it as a tradeoff and dedupe at the file level, or does that have the same problems? And why exactly is deduping important for a personal use case, bandwidth is relatively cheap. In any case, while I want security in these systems to avoid mass survey style attacks, I assume anything I put over the wire to be compromised at least potentially. I keep the kind of files that need that level of encryption on encrypted flash drives.

enscr 12y ago
If you are encrypting each file individually, you are still giving away the file names. Hence you use encrypted file containers. They benefit from block level deduplication. They can be large in size.
- icebraining 12y ago
  If you are encrypting each file individually, you are still giving away the file names. Hence you use encrypted file containers. That doesn't follow - you can solve the problem without containers, e.g. by encrypting or hashing the filenames. Containers protect the file sizes, but they lose the ability to selectively sync certain files to certain nodes.
  - enscr 12y ago
    Hashing doesn't solve the problem completely. You are still giving away information about file count, size & hierarchy. Regarding selective sync : you'll have to organize the files logically into containers. I think even Dropbox doesn't let you sync files selectively, you have to have content separated into folders. I'm not saying that one is better than other, just giving an example of where de-duping at block level is needed as @lugg asked.
    - icebraining 12y ago
      Hashing doesn't solve the problem completely. You are still giving away information about file count, size & hierarchy. Sure; I was just talking about the file names. You can avoid the hierarchy part by transmitting it separately from the files in a secure way, though. Regarding selective sync : you'll have to organize the files logically into containers. I think even Dropbox doesn't let you sync files selectively, you have to have content separated into folders. git-annex does. You can implement rules to decide what files should be synced, which should be dropped locally, etc. For example, an MP3 player running it might have a rule such as filename(*.mp3) or filename(*.ogg) and it'll only sync those files, regardless of their directories.

icebraining 12y ago

git-annex avoid all except (2), by simply encrypting each file using GnuPG, and applying an HMACSHA1 to the filenames. http://git-annex.branchable.com/encryption/ http://git-annex.branchable.com/encryption/

stinos 12y ago
no doubt it would be my first choice if it had proper windows support, but last time I checked that was still lacking
higherpurpose 12y ago
SHA1?
- icebraining 12y ago
  It's configurable. The default MAC algorithm to be applied on the filenames is HMACSHA1. A stronger one, for instance HMACSHA512, one can be chosen upon creation of the special remote with the option mac=HMACSHA512. The available MAC algorithms are HMACSHA1, HMACSHA224, HMACSHA256, HMACSHA384, and HMACSHA512.
- gioele 12y ago
  Don't worry, git-annex uses SHA1 just as a checksum, not for cryptographic purposes.
berdario 12y ago
I tried to use git annex assistant: I can get files to be backed-up on a server, but when doing sync between 2 different machines it has never worked (I've been doing the xmpp-setup dance multiple times, and it's especially painful due to having 2factor auth enabled on google) I'll have to try using plain git annex from the commandline to try to understand what is going wrong (I already used it to clean some repositories that the assistant was refusing to delete) PS: I tried it with 2 machines in the same LAN (both linux... though one of the 2 distros had a slightly older version of the git-annex package)

abus 12y ago

Are there any issues you suspect Syncthing could suffer from?