int DH_get_ex_new_index(long argl, void *argp, CRYPTO_EX_new *new_func,
CRYPTO_EX_dup *dup_func, CRYPTO_EX_free *free_func);
int DH_set_ex_data(DH *d, int idx, void *arg);
int DH_get_ex_new_index(long argl, void *argp, CRYPTO_EX_new *new_func,
CRYPTO_EX_dup *dup_func, CRYPTO_EX_free *free_func);
int DH_set_ex_data(DH *d, int idx, void *arg);