iOS WG (1.0.3) - ARM64 SIMD ChaCha20

[Lonnie Abelbeck]

Thanks to Jason and the team, a new iOS WG 1.0.3 appeared as an update:

1.0.3 / Feb 19, 2019
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Performance should be higher and battery usage lower, thanks to a new ARM64 SIMD implementation of ChaCha20
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For reference, the upstream golang crypto commit is here [1] with performance numbers.

So, the question come to mind, do my iOS devices have ARM64 SIMD support, quick answer is if the device is less than 6 years old it should have ARM64 SIMD support.  Added in the A5/A6 CPU's from what I can tell.

Apple-designed processors
https://en.wikipedia.org/wiki/Apple-designed_processors

Please correct my research if I over-simplified where the new ARM64 SIMD implementation of ChaCha20 is available for iOS WireGuard.

Lonnie

[1] chacha20: add SIMD implementation on arm64
https://go.googlesource.com/crypto/+/74369b46fc6756741c016591724fd1cb8e26845f