问题
I am writing a cryptography application and need to work with 128 bit integers.
In addition to standard add, subtract, multiply, divide, and comparisons, I also need a power and modulo function as well.
Does anyone know of a library or other implementation that can do this? If not 128-bit, is there a 64-bit option available?
回答1:
Check out the GNU Multiple Precision Arithmetic Library.
回答2:
Most any modern compiler is going to provide at least 64 bit through the use of the long long type.
回答3:
gcc supports uint128_t, which is a 128-bit integer, though this isn't very portable.
Since I don't know any main stream cryptosystems that use 128-bit modular arithmetic, I'm wondering what scheme you are implementing.
回答4:
Look for the Montgomery algorithms for multiplication and powers in a finite field. I don't know any library but I am quiet sure there are.
来源：https://stackoverflow.com/questions/2604271/is-there-a-library-or-other-way-to-do-128-bit-math-operations