I'm glad to announce Encounter, a software library aimed at providinga production-grade implementation of cryptographic counters andfostering further research on their constructions and applications.
A cryptographic counter is a public string representing an encryption of a quantity, satisfying the following properties: 1. Subjects with access to the *public-key* can update the encrypted counter by an arbitrary amount, by means of increment or decrement operations and without first decrypting the value (i.e., the operation is performed over encrypted data); 2. The plaintext value is hidden from all participants except the entity holding some secret key; 3. The adversary can only learn if the cryptographic counter was updated (i.e., information about whether the counter was incremented or decremented is kept hidden to all participants except the secret-key holder and the updating entity -- honest-but-curious threat model). Cryptocounters have a number of applications ranging from privacy-preserving statistics gathering in a honest-but-curious threat model, to secure electronic voting, to digital rights management, and cryptovirology. For more, please check this blog post out: http://plaintext.crypto.lo.gy/article/658/encounter and fork the source code (released under the BSD license) at: https://github.com/secYOUre/Encounter Interested? Please, be in touch. Cheers, -- alfonso blogs at http://Plaintext.crypto.lo.gy tweets @secYOUre _______________________________________________ p2p-hackers mailing list p2p-hackers@lists.zooko.com http://lists.zooko.com/mailman/listinfo/p2p-hackers
