4 ms·

You can't. WhatsApp is proprietary software that you aren't allowed to audit. Use free software chat programs instead.

by davexunit 12y ago

switch007 12y ago
How can I (developer, no security knowledge) verify that <open_source_alternative> does encryption properly?
- tptacek 12y ago
  You should assume it can't. The track record is very, very poor.
  - srslack 12y ago
    That's a funny statement, considering PGP and OTR is the go-to and has held up for all of these years.
    - tptacek 12y ago
      What's the next example?
      - srslack 12y ago
        Truecrypt, also confirmed by NSA documents published by Der Spiegel to be 'catastrophic.' OpenVPN. SSH-2 with RSA keys. What proprietary software with good track records did you have in mind?
        tptacek 12y ago
        Truecrypt isn't a messaging system, is barely open source, and is barely trusted (though I think that's unfair). Compare, on the other hand, to "real" open-source disk encryption projects like EncFS/Ecryptfs. OpenVPN is built on OpenSSL and was Heartbleedable. Until a few years ago, SSH was a fiasco. Cryptographically, it has approximately the same security track record as SSL. It's also not a messaging system. I didn't say I had a closed-source alternative for you. There aren't good answers here. I like TextSecure. I also like GPG, a lot. And I have a 4-figure bet with Matthew Green that OTR is more resilient than the other messaging systems. But OTR is mostly only OK if you don't use it with an actual chat client; once libpurple is in the picture, nothing is OK anymore.
        sarciszewski 12y ago
        How about investing money and/or developer hours into securing libpurple then? :)
        loadaverage 12y ago
        how is SSH a fiasco? i'd love to read more about that. "approximately the same security track record as SSL"? i'd say heartbleedable (openssl ssl) vs not heartbleedable (openssh) would be a rather incorrect approximation. also, a messaging system could be tunneled through ssh.
- JoshTriplett 12y ago
  Look for reviews by reputable security experts. Look for use of a standard cryptographic library, preferably a high-level hard-to-get-it-wrong library, rather than hand-rolled cryptography.

You can't. WhatsApp is proprietary software that you aren't allowed to audit. Use free software chat programs instead.

switch007 12y ago

How can I (developer, no security knowledge) verify that <open_source_alternative> does encryption properly?

tptacek 12y ago
You should assume it can't. The track record is very, very poor.
- srslack 12y ago
  That's a funny statement, considering PGP and OTR is the go-to and has held up for all of these years.
  - tptacek 12y ago
    What's the next example?
    - srslack 12y ago
      Truecrypt, also confirmed by NSA documents published by Der Spiegel to be 'catastrophic.' OpenVPN. SSH-2 with RSA keys. What proprietary software with good track records did you have in mind?
      - tptacek 12y ago
        Truecrypt isn't a messaging system, is barely open source, and is barely trusted (though I think that's unfair). Compare, on the other hand, to "real" open-source disk encryption projects like EncFS/Ecryptfs. OpenVPN is built on OpenSSL and was Heartbleedable. Until a few years ago, SSH was a fiasco. Cryptographically, it has approximately the same security track record as SSL. It's also not a messaging system. I didn't say I had a closed-source alternative for you. There aren't good answers here. I like TextSecure. I also like GPG, a lot. And I have a 4-figure bet with Matthew Green that OTR is more resilient than the other messaging systems. But OTR is mostly only OK if you don't use it with an actual chat client; once libpurple is in the picture, nothing is OK anymore.
        sarciszewski 12y ago
        How about investing money and/or developer hours into securing libpurple then? :)
        loadaverage 12y ago
        how is SSH a fiasco? i'd love to read more about that. "approximately the same security track record as SSL"? i'd say heartbleedable (openssl ssl) vs not heartbleedable (openssh) would be a rather incorrect approximation. also, a messaging system could be tunneled through ssh.
JoshTriplett 12y ago
Look for reviews by reputable security experts. Look for use of a standard cryptographic library, preferably a high-level hard-to-get-it-wrong library, rather than hand-rolled cryptography.