My application is here: http://www.cs.queensu.ca/~thurston/fif/
I'm encrypting messages and making them publicly available over static HTTP. Anyone who knows the right URL can grab a message and I don't want recipients to be identifiable. Another issue is that the number of recipients and the size of messages may both get very large. A single encrypted message is therefore very attractive. Thanks, Adrian David Shaw wrote: > On Tue, Feb 05, 2008 at 12:02:48PM -0500, Adrian Thurston wrote: >> Hi, >> >> I'd like to serve messages that have been encrypted to a large number of >> people, however I don't want to reveal the list of recipients so I'm >> going to use --throw-keys. >> >> But speed at the decryption end is a concern, so I thought I would break >> up an encrypted message into packets and when a client requests it serve >> up only the packet that corresponds to the session key encrypted to >> them, then the content packet. I haven't tried it yet, but it seems as >> though it should work. I'd like to know if there is any non-obvious >> reason why it is a bad idea. > > It's hard to really answer this as there isn't enough information to > say one way or another. > > Speaking strictly to your question, and not the "is this wise" > question, if I understand it, you are proposing encrypting to a large > number of people, breaking the resultant encrypted message into many > PKESK packets (one per recipient) and one encrypted packet. Then, > send each recipient their own PKESK plus the encrypted packet. > > So, yes, that would work. GPG even ships with the tools to make such > a message. And it's safe to do so with the caveat that every user > will have the same encrypted message and be able to decrypt it. On > the one hand, no big deal, becuase you sent everyone the same message, > so you clearly wanted them to have it. On the other hand, it gives > Alice the ability to know that Baker got the same message that Alice > did. Whether that is important or not depends on what you are doing. > > Also, given that you are only sending each recipient their own PKESK, > why bother to use --throw-keyid ? It might be easier to just encrypt > the whole message to each recipient individually rather than do all > the packet surgery. > > David > > _______________________________________________ > Gnupg-users mailing list > Gnupg-users@gnupg.org > http://lists.gnupg.org/mailman/listinfo/gnupg-users > > _______________________________________________ Gnupg-users mailing list Gnupg-users@gnupg.org http://lists.gnupg.org/mailman/listinfo/gnupg-users
