tree f154c7580b574b1237e5c5f819da70241fed7a59
parent f3debbd70c6ee3e5ca85bd4ebae8a4bcceede99f
author Asim Shankar <ashankar@google.com> 1449779740 -0500
committer Asim Shankar <ashankar@google.com> 1449779740 -0500

ibe: Avoid copies of bn256.{G1,G2,GT} objects

While the golang.org/x/crypto/bn256 implementation is amenable
to these object copies, other implementations such as
github.com/asimshankar/bn256 are not.

The motivation for this change was so that we experiment with switching
to the pairing implementation backed by
https://www.cryptojedi.org/crypto/#dclxvi

Without this patch, switching to github.com/asimshankar/bn256 causes
SIGSEGVs as copying the Go-objects might mess up the state in C.

For the curious: This change by itself shows no change in the
benchmarks, but switching to https://www.cryptojedi.org/crypto/#dclxvi
shows a considerable improvement on my amd64 machine:
BenchmarkExtractBB1-6  33ms   1ms (16x speedup)
BenchmarkEncryptBB-6   41ms   5ms (7x speedup)
BenchmarkDecryptBB-6   96ms   5ms (16x speedup)

Change-Id: I3409e2df62980c974f3917ef30e8422bfc4a8b37