With openssl version 3, which is installed with ubuntu 22.04, there are compiler-warnings like this:
../../../libKitsunemimiCrypto/src/signing.cpp:35:33: warning: 'HMAC_CTX* HMAC_CTX_new()' is deprecated: Since OpenSSL 3.0 [-Wdeprecated-declarations]
35 | HMAC_CTX* ctx = HMAC_CTX_new();
| ~~~~~~~~~~~~^~
In file included from ../../../libKitsunemimiCrypto/include/libKitsunemimiCrypto/signing.h:14,
from ../../../libKitsunemimiCrypto/src/signing.cpp:9:
/usr/include/openssl/hmac.h:33:33: note: declared here
33 | OSSL_DEPRECATEDIN_3_0 HMAC_CTX *HMAC_CTX_new(void);
| ^~~~~~~~~~~~
The binary still build, but this has to be fixed.