Technology

71922 readers

6152 users here now

This is a most excellent place for technology news and articles.

Our Rules

Follow the lemmy.world rules.
Only tech related news or articles.
Be excellent to each other!
Mod approved content bots can post up to 10 articles per day.
Threads asking for personal tech support may be deleted.
Politics threads may be removed.
No memes allowed as posts, OK to post as comments.
Only approved bots from the list below, this includes using AI responses and summaries. To ask if your bot can be added please contact a mod.
Check for duplicates before posting, duplicates may be removed
Accounts 7 days and younger will have their posts automatically removed.

Approved Bots

founded 2 years ago

MODERATORS

[email protected]

342

The Guardian and Cambridge University's Department of Computer Science unveil new secure technology to protect sources (www.theguardian.com)

submitted 3 days ago* (last edited 3 days ago) by [email protected] to c/[email protected]

59 comments fedilink hide all child comments

Academic paper: https://www.cl.cam.ac.uk/techreports/UCAM-CL-TR-999.pdf

you are viewing a single comment's thread
view the rest of the comments

[–] [email protected] 5 points 1 day ago* (last edited 1 day ago) (1 children)

Technical summary: it seems OK against an observer who can see the network traffic but hasn't infiltrated the phone of the source or the computer of the news organization.

Any real message is stored locally on the smartphone by the CoverDrop module and sent as the next CoverDrop message, i.e. replacing the dummy message which would otherwise have been sent. Consequently a network observer cannot determine whether any communication is taking place and CoverDrop therefore provides the potential source with plausible deniability.

The CoverNode and each journalist has their own public-private key pair. These keys are published by the news organization and available to the CoverDrop module directly so the user does not need know about them. When the CoverDrop module is used for the first time, it generates a new, random public-private key pair for the user.

All real CoverDrop messages sent by the CoverDrop module to the CoverNode include the text written by the potential source as well as their own public key. The message is first encrypted using the public key of the journalist who will ultimately receive the message, then encrypted a second time using the public key of the CoverNode. All dummy CoverDrop messages are encrypted using the public key of the CoverNode. All messages, real or dummy, are arranged to be the same, fixed length. Encryption and length constraints ensure that only the CoverNode can distinguish between real and dummy messages.

[–] [email protected] 6 points 1 day ago

To sum it up even more : this looks like standard end-to-end encryption, but any app user have the same network traffic, completed with fake data if no communication is needed.