'core/crypto.h' file not found error when compiling code

[tysyzp]

In file included from dtls_misc.c:35:
./tls.h:43:10: fatal error: 'core/crypto.h' file not found
#include "core/crypto.h"
^~~~~~~~~~~~~~~
1 error generated.
In file included from dtls_record.c:35:
./tls.h:43:10: fatal error: 'core/crypto.h' file not found
#include "core/crypto.h"
^~~~~~~~~~~~~~~
1 error generated.
In file included from tls.c:41:
./tls.h:43:10: fatal error: 'core/crypto.h' file not found
#include "core/crypto.h"
^~~~~~~~~~~~~~~
1 error generated.

[jedisct1]

I guess the files from https://github.com/Oryx-Embedded/CycloneCRYPTO are also needed.