crypto/dh/dh_key.c

1 /* crypto/dh/dh_key.c */
63 #include <openssl/dh.h>
65 static int generate_key(DH *dh);
66 static int compute_key(unsigned char *key, const BIGNUM *pub_key, DH *dh);
67 static int dh_bn_mod_exp(const DH *dh, BIGNUM *r,
70 static int dh_init(DH *dh);
71 static int dh_finish(DH *dh);
73 int DH_generate_key(DH *dh)
76     if (FIPS_mode() && !(dh->meth->flags & DH_FLAG_FIPS_METHOD)
77         && !(dh->flags & DH_FLAG_NON_FIPS_ALLOW)) {
82     return dh->meth->generate_key(dh);
85 int DH_compute_key(unsigned char *key, const BIGNUM *pub_key, DH *dh)
88     if (FIPS_mode() && !(dh->meth->flags & DH_FLAG_FIPS_METHOD)
89         && !(dh->flags & DH_FLAG_NON_FIPS_ALLOW)) {
94     return dh->meth->compute_key(key, pub_key, dh);
114 static int generate_key(DH *dh)
127     if (dh->priv_key == NULL) {
133         priv_key = dh->priv_key;
135     if (dh->pub_key == NULL) {
140         pub_key = dh->pub_key;
142     if (dh->flags & DH_FLAG_CACHE_MONT_P) {
143         mont = BN_MONT_CTX_set_locked(&dh->method_mont_p,
144                                       CRYPTO_LOCK_DH, dh->p, ctx);
150         if (dh->q) {
152                 if (!BN_rand_range(priv_key, dh->q))
158             l = dh->length ? dh->length : BN_num_bits(dh->p) - 1;
168         if ((dh->flags & DH_FLAG_NO_EXP_CONSTTIME) == 0) {
175         if (!dh->meth->bn_mod_exp(dh, pub_key, dh->g, prk, dh->p, ctx, mont))
179     dh->pub_key = pub_key;
180     dh->priv_key = priv_key;
186     if ((pub_key != NULL) && (dh->pub_key == NULL))
188     if ((priv_key != NULL) && (dh->priv_key == NULL))
194 static int compute_key(unsigned char *key, const BIGNUM *pub_key, DH *dh)
202     if (BN_num_bits(dh->p) > OPENSSL_DH_MAX_MODULUS_BITS) {
213     if (dh->priv_key == NULL) {
218     if (dh->flags & DH_FLAG_CACHE_MONT_P) {
219         mont = BN_MONT_CTX_set_locked(&dh->method_mont_p,
220                                       CRYPTO_LOCK_DH, dh->p, ctx);
221         if ((dh->flags & DH_FLAG_NO_EXP_CONSTTIME) == 0) {
223             BN_set_flags(dh->priv_key, BN_FLG_CONSTTIME);
229     if (!DH_check_pub_key(dh, pub_key, &check_result) || check_result) {
234     if (!dh->
235         meth->bn_mod_exp(dh, tmp, pub_key, dh->priv_key, dh->p, ctx, mont)) {
249 static int dh_bn_mod_exp(const DH *dh, BIGNUM *r,
257     if (a->top == 1 && ((dh->flags & DH_FLAG_NO_EXP_CONSTTIME) != 0)) {
264 static int dh_init(DH *dh)
266     dh->flags |= DH_FLAG_CACHE_MONT_P;
270 static int dh_finish(DH *dh)
272     if (dh->method_mont_p)
273         BN_MONT_CTX_free(dh->method_mont_p);