static int ubsec_mod_exp(BIGNUM *r, const BIGNUM *a, const BIGNUM *p,
const BIGNUM *m, BN_CTX *ctx);
static int ubsec_mod_exp_crt(BIGNUM *r, const BIGNUM *a, const BIGNUM *p,
const BIGNUM *q, const BIGNUM *dp,
const BIGNUM *dq, const BIGNUM *qinv, BN_CTX *ctx);
#ifndef OPENSSL_NO_RSA
static int ubsec_mod_exp(BIGNUM *r, const BIGNUM *a, const BIGNUM *p,
const BIGNUM *m, BN_CTX *ctx);
static int ubsec_mod_exp_crt(BIGNUM *r, const BIGNUM *a, const BIGNUM *p,
const BIGNUM *q, const BIGNUM *dp,
const BIGNUM *dq, const BIGNUM *qinv, BN_CTX *ctx);
#ifndef OPENSSL_NO_RSA