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"the adversary would have access at least to the envelope information." This is a strawman, because Lavabit never did anything to protect headers. What you ar

"the adversary would have access at least to the envelope information." This is a strawman, because Lavabit never did anything to protect headers. What you are missing is that Lavabit could respond to a demand for plaintext, if Ladar were willing to do so; on the other hand, Google cannot give anyone access to the plaintexts of PGP encrypted messages that I send through their servers because of technical barriers. That is the point of doing your encryption locally, and that is why security and privacy are not a service. "Indeed, it is not. If the hacker gets full control of your mailserver, at least your envelope information is completely compromised." Except that with Lavabit, an attacker could also get all your message bodies. "Security depended on adversary not having full access to the Lavabit servers, not on Ladar's "whim"." Let's put it this way: if you were involved in a lawsuit against Ladar, would you trust your communications with your lawyer to Lavabit? Of course not, because Ladar could have modified the code at any time and without alerting his users at all to read any plaintext that he wanted to read. If he had been willing to cooperate with the government, he could have and nobody would have a clue. "Assuming your adversary doesn't have full access to your service is kind of a precondition of using the service as means of security." In other words, security is not something you can get as a service. The entire model is fundamentally and fatally broken. "That's like using lock is assuming the adversary does not have the key, if he does, the lock is useless as a security measure" No, it is like storing your key with the bartender at your favorite night club and assuming that he will not allow your adversaries to use it. "As soon as Lavabit became essentially useless for the purpose it was created, it was shut down." It was shut down because Ladar chose to shut it down rather than capitulate. He could have chosen to keep it going while the government eavesdropped on it instead. That means that, as I said, security boiled down to Ladar and his principles. That is why PGP and S/MIME provide you with better security: mathematics are not subject to the choices that human beings make, and with PGP, S/MIME, etc. your security is a matter of mathematics.

smsm42 13y ago
>>> This is a strawman, because Lavabit never did anything to protect headers. Since SSL keys are mentioned, I assume SSL was used in communication. This means the claim that Lavabit did nothing to protect headers is false. >>> Except that with Lavabit, an attacker could also get all your message bodies. This is true, however body of the message may contain encrypted information, which is useless to observer. Envelope information can not be encrypted in a way that is not readable by the mail server, that's the point of the mail server. >>> The entire model is fundamentally and fatally broken. That is kind of what I was saying - that current technology of the email can not do what Lavabit tried to do if the adversary can do what the courts said it can do. I'm not sure what you're disagreeing with here. >>> He could have chosen to keep it going while the government eavesdropped on it instead. That would be a betrayal of his user's trust, since any claim about what his service does would be necessarily false and he would become a liar if he ever claimed his server allows to communicate securely. I agree that this boils down to one's principles. I think a principle of "don't lie to your customers" is a good one to have. >>> That is why PGP and S/MIME provide you with better security No they do not, unless you can establish a peer-to-peer channel with your other party. In which case you're not using email anymore. Neither PGP nor S/MIME can prevent adversary from collecting envelope information in emails, and unability to do this is what made Lavabit impossible to continue. >>> mathematics are not subject to the choices that human beings make, You seem to be either genuinely confused about how email works and what running a secure email server involves, or trying to say something else than you're actually saying, or not making any sense. There are no "choices" that allow you to create secure email server in situation in which Lavabit found itself.
- betterunix 13y ago
  "Since SSL keys are mentioned, I assume SSL was used in communication. This means the claim that Lavabit did nothing to protect headers is false." That is like saying that GMail is protecting the privacy of your headers, because GMail uses SSL. "This is true, however body of the message may contain encrypted information, which is useless to observer" Except that in the case of Lavabit, that encryption was just a side show since all the cryptographic operations were performed on the server. "current technology of the email can not do what Lavabit tried to do if the adversary can do what the courts said it can do" Except that someone who encrypts their message bodies before sending the message i.e. performing cryptographic operations locally leaves the server unable to fulfill demands for plaintexts. ">>> That is why PGP and S/MIME provide you with better security No they do not, unless you can establish a peer-to-peer channel with your other party. In which case you're not using email anymore." Really, you think I am not using email anymore if I am running my own personal mail server? It is also false to claim that one must have a peer-to-peer system to protect header information, or that PGP on its own is not enough. You could broadcast an encrypted message via Usenet. You could use anonymous remailers (e.g. "Type I" remailers, which use PGP). In all these cases, however, you need to perform your cryptographic operations locally. "There are no "choices" that allow you to create secure email server in situation in which Lavabit found itself." Sure there are: Ladar could have sold smartcards instead of selling cryptography as a service. There, one design decision that could have given his users meaningful security while still maintaining the convenience of webmail. To boost security even more, those smartcards could be coupled with a thumb drive that includes the necessary client software, so that Lavabit could not pull a Hushmail on its users.
  - smsm42 13y ago
    >>> That is like saying that GMail is protecting the privacy of your headers, because GMail uses SSL. It does. Unlike Lavabit, though, there is ample reason to assume they invalidate this protection by granting governmental adversaries access to the information stored on their servers - the thing that Lavabit refused to do, at least on mass scale. >>> since all the cryptographic operations were performed on the server. I don't see what precludes you from sending emails already encrypted. Security has layers. You are not limited to using just one. >>> leaves the server unable to fulfill demands for plaintexts. You forgot to read the part of my answer where I use the word "envelope". >>> Really, you think I am not using email anymore if I am running my own personal mail server? It is irrelevant what you personally are doing - it is relevant what Lavabit was trying to do. They were trying to provide certain service - for people that - like, I assume, most of Guardian journalists - are not technically advanced enough to run a secure mail server on their personal computer and set up everything else in a way that allows it to accept email from the internet. This proved impossible, thus Lavabit is not with us anymore. That was my whole point. >>> Ladar could have sold smartcards instead of selling cryptography as a service. He could also have sold hotdogs and Carribean timeshares, how that's related to the topic? He was trying to create a secure email as a service - for those that can not create the same by themselves, which in 99.999% of the population of email users. Not provide solution for completely different problem such as key exchange and creating VPNs and other stuff.

smsm42 13y ago

>>> This is a strawman, because Lavabit never did anything to protect headers. Since SSL keys are mentioned, I assume SSL was used in communication. This means the claim that Lavabit did nothing to protect headers is false. >>> Except that with Lavabit, an attacker could also get all your message bodies. This is true, however body of the message may contain encrypted information, which is useless to observer. Envelope information can not be encrypted in a way that is not readable by the mail server, that's the point of the mail server. >>> The entire model is fundamentally and fatally broken. That is kind of what I was saying - that current technology of the email can not do what Lavabit tried to do if the adversary can do what the courts said it can do. I'm not sure what you're disagreeing with here. >>> He could have chosen to keep it going while the government eavesdropped on it instead. That would be a betrayal of his user's trust, since any claim about what his service does would be necessarily false and he would become a liar if he ever claimed his server allows to communicate securely. I agree that this boils down to one's principles. I think a principle of "don't lie to your customers" is a good one to have. >>> That is why PGP and S/MIME provide you with better security No they do not, unless you can establish a peer-to-peer channel with your other party. In which case you're not using email anymore. Neither PGP nor S/MIME can prevent adversary from collecting envelope information in emails, and unability to do this is what made Lavabit impossible to continue. >>> mathematics are not subject to the choices that human beings make, You seem to be either genuinely confused about how email works and what running a secure email server involves, or trying to say something else than you're actually saying, or not making any sense. There are no "choices" that allow you to create secure email server in situation in which Lavabit found itself.

betterunix 13y ago
"Since SSL keys are mentioned, I assume SSL was used in communication. This means the claim that Lavabit did nothing to protect headers is false." That is like saying that GMail is protecting the privacy of your headers, because GMail uses SSL. "This is true, however body of the message may contain encrypted information, which is useless to observer" Except that in the case of Lavabit, that encryption was just a side show since all the cryptographic operations were performed on the server. "current technology of the email can not do what Lavabit tried to do if the adversary can do what the courts said it can do" Except that someone who encrypts their message bodies before sending the message i.e. performing cryptographic operations locally leaves the server unable to fulfill demands for plaintexts. ">>> That is why PGP and S/MIME provide you with better security No they do not, unless you can establish a peer-to-peer channel with your other party. In which case you're not using email anymore." Really, you think I am not using email anymore if I am running my own personal mail server? It is also false to claim that one must have a peer-to-peer system to protect header information, or that PGP on its own is not enough. You could broadcast an encrypted message via Usenet. You could use anonymous remailers (e.g. "Type I" remailers, which use PGP). In all these cases, however, you need to perform your cryptographic operations locally. "There are no "choices" that allow you to create secure email server in situation in which Lavabit found itself." Sure there are: Ladar could have sold smartcards instead of selling cryptography as a service. There, one design decision that could have given his users meaningful security while still maintaining the convenience of webmail. To boost security even more, those smartcards could be coupled with a thumb drive that includes the necessary client software, so that Lavabit could not pull a Hushmail on its users.
- smsm42 13y ago
  >>> That is like saying that GMail is protecting the privacy of your headers, because GMail uses SSL. It does. Unlike Lavabit, though, there is ample reason to assume they invalidate this protection by granting governmental adversaries access to the information stored on their servers - the thing that Lavabit refused to do, at least on mass scale. >>> since all the cryptographic operations were performed on the server. I don't see what precludes you from sending emails already encrypted. Security has layers. You are not limited to using just one. >>> leaves the server unable to fulfill demands for plaintexts. You forgot to read the part of my answer where I use the word "envelope". >>> Really, you think I am not using email anymore if I am running my own personal mail server? It is irrelevant what you personally are doing - it is relevant what Lavabit was trying to do. They were trying to provide certain service - for people that - like, I assume, most of Guardian journalists - are not technically advanced enough to run a secure mail server on their personal computer and set up everything else in a way that allows it to accept email from the internet. This proved impossible, thus Lavabit is not with us anymore. That was my whole point. >>> Ladar could have sold smartcards instead of selling cryptography as a service. He could also have sold hotdogs and Carribean timeshares, how that's related to the topic? He was trying to create a secure email as a service - for those that can not create the same by themselves, which in 99.999% of the population of email users. Not provide solution for completely different problem such as key exchange and creating VPNs and other stuff.