We store measurement results in directories. Each directory has a meta.xml which describes common things about the result file, and several files of data. This result has to be encrypted.
I would dream of a solution like this:
Is this solution realizable? Are there open-source libraries which do the job? Which encryption algorithm to use?
Best regards!
gpg -c
to symmetrically encrypt - sarnold 2012-04-04 07:57
The use of AES encryption in zip files is supported by PKZip, WinZip, and 7-Zip and is specified in the PKWare zip appnote and well described here: Encryption Specification AE-1 and AE-2. Unfortunately neither Info-ZIP zip nor unzip currently support it (those are what you find on Unixish systems). 7-Zip is open source. As noted, the original zip "encryption" hardly even deserves the name and so should be avoided at all costs. The standardized AES encryption is strong, usable, and relatively widely supported.
Update:
I just noticed another part of your question. Each zip entry can be separately encrypted with a different password, and in fact you can mix unencrypted entries as well in the same zip file.