ByteBuffer::slice_view() allocates a new ByteBuffer object,
which as a RefPtr and everything.
Nowadays it should probably return a Bytes / Span<u8>, but AES was only
using slice_view() to extract the pointer again. So just add ady a
range check at the top, and do pointer arithmetic to do the same thing
faster.
Reduces time to run `disasm /bin/id` by a bit under 40%,
from ~8.3s to ~5s (min-of-3 runs).
This is in preparation for the upcoming Galois/Counter mode, which
conventionally has 12 bytes of IV as opposed to CBC's 16 bytes.
...Also fixes a lot of style issues, since the author finally found the
project's clang config file in the repository root :^)
This commit fixes up the following:
- HMAC should not reuse a single hasher when successively updating
- AES Key should not assume its user key is valid signed char*
- Mode should have a virtual destructor
And adds a RFC5246 padding mode, which is required for TLS
