kctx;
unsigned char out[10];
OSSL_PARAM params[6], *p = params;

kdf = EVP_KDF_fetch(NULL, &quot;SSKDF&quot;, NULL);
kctx = EVP_KDF_CTX_new(kdf);
EVP_KDF_free(kdf);

*p++ = OSSL_PARAM_construct_utf8_string(OSSL_KDF_PARAM_MAC,
                                        SN_hmac, strlen(SN_hmac));
*p++ = OSSL_PARAM_construct_utf8_string(OSSL_KDF_PARAM_DIGEST,
                                        SN_sha256, strlen(SN_sha256));
*p++ = OSSL_PARAM_construct_octet_string(OSSL_KDF_PARAM_SECRET,
                     