We present a modular framework for the design of efficient
adaptively secure attribute-based encryption (ABE) schemes for a
large class of predicates under the standard k-Lin assumption
in prime-order groups; this is the first uniform treatment of dual
system ABE across different predicates and across both composite and
prime-order groups. Via this framework, we obtain concrete
efficiency improvements for several ABE schemes. Our framework has
three novel components over prior works: (i) new techniques for
simulating composite-order groups in prime-order ones, (ii) a
refinement of prior encodings framework for dual system ABE in
composite-order groups, (iii) an extension to weakly
attribute-hiding predicate encryption (which includes anonymous
identity-based encryption as a special case).
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