Fixed time AES cipher
modulename: aes_ti.ko
configname: CONFIG_CRYPTO_AES_TI
Linux Kernel Configuration
└─>Cryptographic API
└─>Fixed time AES cipher
In linux kernel since version 3.10 (release Date: 2013-06-30)
This is a generic implementation of AES that attempts to eliminate
data dependent latencies as much as possible without affecting
performance too much. It is intended for use by the generic CCM
and GCM drivers, and other CTR or CMAC/XCBC based modes that rely
solely on encryption (although decryption is supported as well, but
with a more dramatic performance hit)
Instead of using 16 lookup tables of 1 KB each, (8 for encryption and
8 for decryption), this implementation only uses just two S-boxes of
256 bytes each, and attempts to eliminate data dependent latencies by
prefetching the entire table into the cache at the start of each
block. Interrupts are also disabled to avoid races where cachelines
are evicted when the CPU is interrupted to do something else.
data dependent latencies as much as possible without affecting
performance too much. It is intended for use by the generic CCM
and GCM drivers, and other CTR or CMAC/XCBC based modes that rely
solely on encryption (although decryption is supported as well, but
with a more dramatic performance hit)
Instead of using 16 lookup tables of 1 KB each, (8 for encryption and
8 for decryption), this implementation only uses just two S-boxes of
256 bytes each, and attempts to eliminate data dependent latencies by
prefetching the entire table into the cache at the start of each
block. Interrupts are also disabled to avoid races where cachelines
are evicted when the CPU is interrupted to do something else.