RSA encryption/signing using Solaris Kernel Crypto Framework (KCF) is lagging behind benchmarks from OpenSSL 0.9.8j on amd64 Solaris Nevada.
Almost all of RSA time is spent in the bignum kernel module, so that is where performance gains must originate.
This CR is to provide further performance benefit in addition to:
6799218 RSA using Solaris Kernel Crypto framework lagging behind OpenSSL
which was putback to NV110 and improved performance by improving the bignum library. The previous improvement from changing from 32-bit chunks (bignum "digits") to 64-bit chunks for Solaris amd64 architecture.
The further performance benefit is from a patch by Amitabha Banerjee, who found that bignum's big_mul() function took a lot of time and found some optimization tricks that could be done to the routine.