Paper 2019/410
Policy-Based Sanitizable Signatures
Kai Samelin and Daniel Slamanig
Abstract
Sanitizable signatures allow a single, and signer-defined, sanitizer to modify signed messages in a controlled way without invalidating the respective signature. They turned out to be a fascinating primitive, proven by different variants and extensions, e.g., allowing multiple sanitizers or adding new sanitizers one-by-one. Still, existing constructions are very limited regarding their flexibility in specifying potential sanitizers. In this paper, we propose a different and more powerful approach: Instead of using the sanitizers' public keys directly, we assign attributes to them. Sanitizing is then based on policies, i.e., access structures defined over attributes. A sanitizer can sanitize, if, and only if, it holds a secret key to attributes satisfying the policy associated to a signature, while offering full-scale accountability.
Metadata
- Available format(s)
- Category
- Public-key cryptography
- Publication info
- Preprint. MINOR revision.
- Keywords
- Sanitizable SignaturesChameleon-HashesDigital Signatures
- Contact author(s)
-
kaispapers @ gmail com
daniel slamanig @ ait ac at - History
- 2020-08-10: last of 3 revisions
- 2019-04-22: received
- See all versions
- Short URL
- https://ia.cr/2019/410
- License
-
CC BY