32void hmac_md5_with_nettle(uint8_t *data, 
size_t  data_len,
 
   33                          uint8_t *key,  
size_t  key_len,
 
   34                          uint8_t  digest[MD5_DIGEST_SIZE])
 
   36    struct hmac_md5_ctx md5;
 
   37    memset(digest, 0, MD5_DIGEST_SIZE);
 
   38    hmac_md5_set_key(&md5, key_len, key);
 
   39    hmac_md5_update(&md5, data_len, data);
 
   40    hmac_md5_digest(&md5, MD5_DIGEST_SIZE, digest);