Per last paragraph of RFC 8446, Section 5.2, the length of the inner content of an encrypted record must not exceed 2^14 + 1, while that of the whole encrypted record must not exceed 2^14 + 256.
Use inline to vastly simplify the exposed API. This allows a
comptime-known endian parameter to be propogated, making extra functions
for a specific endianness completely unnecessary.
Most of this migration was performed automatically with `zig fmt`. There
were a few exceptions which I had to manually fix:
* `@alignCast` and `@addrSpaceCast` cannot be automatically rewritten
* `@truncate`'s fixup is incorrect for vectors
* Test cases are not formatted, and their error locations change
This commit adds `writeEnd` and `writeAllEnd` in order to send data and
also notify the server that there will be no more data written.
Unfortunately, it seems most TLS implementations in the wild get this
wrong and immediately close the socket when they see a close_notify,
rather than only ending the data stream on the application layer.
This commit introduces tls.Decoder and then uses it in tls.Client. The
purpose is to make it difficult to introduce vulnerabilities in the
parsing code. With this abstraction in place, bugs in the TLS
implementation will trip checks in the decoder, regardless of the actual
length of packets sent by the other party, so that we can have
confidence when using ReleaseFast builds.
