Expand description
Fast, SIMD base64 codecs.
This crate implements base64 encoding and decoding as fast as possible.
To get maximum performance, compile with -Ctarget-cpu=native
and
-Zbuild-std
, which will ensure ideal instruction selection.
The following is a perf comparison with the base64
crate on a Zen 2
machine using AVX2 instructions; lower is better.
On a Zen 2 machine and compiling with AVX2 support, decoding is between
2x to 2.5x faster than base64
, while encoding is around 1.2x to 1.5x
faster; with only SSSE3, decoding performance is even with base64
and
encoding is much worse.
It is relatively unlikely that base64 decoding is such a massive bottleneck for your application that this matters, unless you’re parsing base64 blobs embedded in JSON; you may want to consider using a binary format like Protobuf instead.
Also this crate uses std::simd
so it requires nightly.
Constant time?? 👀
For decoding valid base64 (and for encoding any message), the
implementations are essentially constant-time, but mostly by accident, since
they are branchless and use shuffle-based lookup tables. Whether you
want to believe that this decodes your private key .pem
files without
side-channel-leaking key material up to you (OpenSSL 100% leaks your private
keys this way).
Structs
- The error returned by all decode functions.
Functions
- Decodes some base64
data
to a fresh vector. - Decodes some base64 data as base64 and appends it to
out
. - Encodes arbitrary data as base64.
- Encodes arbitrary data as base64 and appends it to
out
.