USENIX Security - 2020
Authors: Chia-Che Tsai, Jeongsok Son, Bhushan Jain, John McAvey, Raluca Ada Popa, Donald E. Porter


Hardware enclaves are designed to execute small pieces ofsensitive code or to operate on sensitive data, in isolation fromlarger, less trusted systems. Partitioning a large, legacy appli-cation requires significant effort. Partitioning an applicationwritten in a managed language, such as Java, is more challeng-ing because of mutable language characteristics, extensivecode reachability in class libraries, and the inevitability ofusing a heavyweight runtime.Civet is a framework for partitioning Java applications intoenclaves. Civet reduces the number of lines of code in theenclave and uses language-level defenses, including deeptype checks and dynamic taint-tracking, to harden the enclaveinterface. Civet also contributes a partitioned Java runtime de-sign, including a garbage collection design optimized for thepeculiarities of enclaves. Civet is efficient for data-intensiveworkloads; partitioning a Hadoop mapper reduces the en-clave overhead from 10×to 16–22% without taint-trackingor 70–80% with taint-tracking.