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You can use SMSSecure as your default messaging app. That way you don't have to switch apps. You can even import your SMS from the default messaging app so that

by Couto 12y ago

You can use SMSSecure as your default messaging app. That way you don't have to switch apps. You can even import your SMS from the default messaging app so that you don't loose your history. Bonus: you can then encrypt those SMS locally, but that's optional. You can toggle the option to send encrypted sms or not, per contact, so if your contact doesn't support SMSSecure, you just send a regular SMS. The ability to know who's using SMSSecure is interesting and not currently supported (that I know of)

pR0Ps 12y ago
Actually, if you receive a message from someone using SMSSecure, you'll get a prompt asking if you want to upgrade to a secure session. But yes, there is no way to look someone up and check if they're using SMSSecure. The detection was actually inherited from TextSecure and works by "tagging" shorter messages with some detectable whitespace after the message contents. A bit of a hack, but it's a limitation of the transport. Relevant commit: https://github.com/SMSSecure/SMSSecure/commit/93d94f2b7a9fd60c5051e2e3845e40bb857cc5ef https://github.com/SMSSecure/SMSSecure/commit/93d94f2b7a9fd6...
- psykovsky 12y ago
  So, that detection can be used by anyone who receives one of my texts to see if I use SMSSecure or not? Isn't that a metadata leak?
  - pR0Ps 12y ago
    Yes, anyone who analyzes the messages you send can assume that you are using SMSSecure. However, compared to the amount of metadata that's already being leaked over SMS[1], adding the fact that you could[2] be using a specific SMS client that has the ability to encrypt messages doesn't seem too bad. There was an option in a previous version of TextSecure to disable this tagging, but it was deemed unused and axed[3]. For the same reason, I'm loathe to add it back in, but having the option shoved under the "Advanced" menu may not be too bad. [1] This is something that TextSecure does much better with. SMS messages (even encrypted) still leak metadata on who you're messaging and when. [2] There's some element of deniability with whitespace tags (granted, not a lot). On the other hand, if you're registered with TextSecure (which can be checked simply by adding a user your contacts and opening the app), there's only one reason you would be there. [3] See https://github.com/WhisperSystems/TextSecure/commit/40eca5e0f600f0579c8e4001da74d19b8785e820 https://github.com/WhisperSystems/TextSecure/commit/40eca5e0...

by Couto 12y ago

pR0Ps 12y ago

Actually, if you receive a message from someone using SMSSecure, you'll get a prompt asking if you want to upgrade to a secure session. But yes, there is no way to look someone up and check if they're using SMSSecure. The detection was actually inherited from TextSecure and works by "tagging" shorter messages with some detectable whitespace after the message contents. A bit of a hack, but it's a limitation of the transport. Relevant commit: https://github.com/SMSSecure/SMSSecure/commit/93d94f2b7a9fd60c5051e2e3845e40bb857cc5ef https://github.com/SMSSecure/SMSSecure/commit/93d94f2b7a9fd6...

psykovsky 12y ago
So, that detection can be used by anyone who receives one of my texts to see if I use SMSSecure or not? Isn't that a metadata leak?
- pR0Ps 12y ago
  Yes, anyone who analyzes the messages you send can assume that you are using SMSSecure. However, compared to the amount of metadata that's already being leaked over SMS[1], adding the fact that you could[2] be using a specific SMS client that has the ability to encrypt messages doesn't seem too bad. There was an option in a previous version of TextSecure to disable this tagging, but it was deemed unused and axed[3]. For the same reason, I'm loathe to add it back in, but having the option shoved under the "Advanced" menu may not be too bad. [1] This is something that TextSecure does much better with. SMS messages (even encrypted) still leak metadata on who you're messaging and when. [2] There's some element of deniability with whitespace tags (granted, not a lot). On the other hand, if you're registered with TextSecure (which can be checked simply by adding a user your contacts and opening the app), there's only one reason you would be there. [3] See https://github.com/WhisperSystems/TextSecure/commit/40eca5e0f600f0579c8e4001da74d19b8785e820 https://github.com/WhisperSystems/TextSecure/commit/40eca5e0...