This commit replaces the old implementation of `EMSA_PKCS1_V1_5` with
one backed by OpenSSL. In doing so, the `sign` and `verify` methods of
RSA have been modified to behave like expected and not just be
encryption and decryption.
I was not able to split this commit because the changes to `verify` and
`sign` break pretty much everything.
It used to be that the caller would supply a buffer to write the output
to. This created an anti-pattern in multiple places where the caller
would allocate a `ByteBuffer` and then use `.bytes()` to provide it to
the `PKSystem` method. Then the callee would resize the output buffer
and reassign it, but because the resize was on `Bytes` and not on
`ByteBuffer`, the caller using the latter would cause a bug.
Additionally, in pretty much all cases the buffer was pre-allocated
shortly before.
- Removed the constructor taking a (n, d, e) tuple and moved
it to `RSAPrivateKey`
- Removed default constructor with key generation because it was always
misused and the default key size is quite small
- Added utility constructors to accept a key pair, public key, private
key or both
- Made constructor parameters const
- Updated test to use generated random keys where possible
The decoding inside `RSA::parse_rsa_key` is quite complex because it
tries to understand if it's decoding PKCS#8 or PKCS#1. Simplify the code
by moving the burden to the PEM decoder.
Add support for encoding parameters in `wrap_in_private_key_info` and
`wrap_in_subject_public_key_info` as well as turn `Span<int>` into
`Span<int const>`.
Each of these strings would previously rely on StringView's char const*
constructor overload, which would call __builtin_strlen on the string.
Since we now have operator ""sv, we can replace these with much simpler
versions. This opens the door to being able to remove
StringView(char const*).
No functional changes.