AWS-LC lacks support for a number of elliptic curve algorithms so this
adds some conditional macros to avoid registering the related plugin
features. Support for curves ed448 and x448 is completely absent and are
not planned for implementation as they are no longer recommended for use.
While ed25519 is supported by the library, a single missing API for
ASN.1 DER encoding of its private keys is missing which prevents its
use in strongSwan. Future work may remove this limitation, but for now
we will disable the functionality.
Closesstrongswan/strongswan#2109
AWS-LC is a BoringSSL-based libcrypto implementation. SHA_CTX is declared with
the hash data specified as an array rather than as a field in upstream OpenSSL.
Since AWS-LC builds against C99, we are unable to handle this with anonymous
unions like BoringSSL. The workaround I propose is to add these conditional
macros around the accessors within openssl_sha1_prf. After this change,
everything builds successfully with AWS-LC headers.
Closesstrongswan/strongswan#2103