Yet another Go ChaCha20 implementation. Everything else I found was slow, didn't support all the variants I need to use, or relied on cgo to go fast.
Features:
- 20 round, 256 bit key only. Everything else is pointless and stupid.
- IETF 96 bit nonce variant.
- XChaCha 24 byte nonce variant.
- SSSE3 and AVX2 support on amd64 targets.
- Incremental encrypt/decrypt support, unlike golang.org/x/crypto/salsa20.