Title: Did we learn from LLC Side Channel Attacks? A Cache Leakage Detection Tool for Crypto Libraries,
Abstract: This work presents a new tool to verify the correctness of cryptographic
implementations with respect to cache attacks. Our methodology discovers
vulnerabilities that are hard to find with other techniques, observed as
exploitable leakage. The methodology works by identifying secret dependent
memory and introducing forced evictions inside potentially vulnerable code to
obtain cache traces that are analyzed using Mutual Information. If dependence
is observed, the cryptographic implementation is classified as to leak
information.
We demonstrate the viability of our technique in the design of the three main
cryptographic primitives, i.e., AES, RSA and ECC, in eight popular up to date
cryptographic libraries, including OpenSSL, Libgcrypt, Intel IPP and NSS. Our
results show that cryptographic code designers are far away from incorporating
the appropriate countermeasures to avoid cache leakages, as we found that 50%
of the default implementations analyzed leaked information that lead to key
extraction. We responsibly notified the designers of all the leakages found and
suggested patches to solve these vulnerabilities.