What steps will reproduce the problem?
1. Test util.hashes.hmac_sha512 using test vectors found inRFC 4231
What is the expected output?
What do you see instead?
Please provide any additional information below.
The implementation in util-src/hashes.c uses a macro to implement all HMAC variants.
Notably the inner hmac() function uses a fixed block size, which is the one used for HMAC-SHA-256, while HMAC-SHA-512 uses a larger block size.
Thanks to darkrain42 for finding out about HMAC-SHA-512 block size.
I have found no code that relies on hmac-sha-512.
Fixing the C code has turned out to be tricky, so it seems easiest to change it to use the HMAC function provided by OpenSSL.