EAP-EKE: Use abstract crypto API

This makes it easier to use EAP-pwd with other crypto libraries.

Signed-off-by: Sean Parkinson <sean@wolfssl.com>

diff --git a/src/eap_common/eap_eke_common.c b/src/eap_common/eap_eke_common.c
index 621746821538b68d3cd5def2e77a868bbb005164..bfe8811e33f27f367449f31ca5b53b6caf3d79ab 100644 (file)
--- a/src/eap_common/eap_eke_common.c
+++ b/src/eap_common/eap_eke_common.c
@@ -161,7 +161,6 @@ int eap_eke_dh_init(u8 group, u8 *ret_priv, u8 *ret_pub)
        int generator;
        u8 gen;
        const struct dh_group *dh;
-       size_t pub_len, i;
 
        generator = eap_eke_dh_generator(group);
        dh = eap_eke_dh_group(group);
@@ -169,33 +168,11 @@ int eap_eke_dh_init(u8 group, u8 *ret_priv, u8 *ret_pub)
                return -1;
        gen = generator;
 
-       /* x = random number 2 .. p-1 */
-       if (random_get_bytes(ret_priv, dh->prime_len))
-               return -1;
-       if (os_memcmp(ret_priv, dh->prime, dh->prime_len) > 0) {
-               /* Make sure private value is smaller than prime */
-               ret_priv[0] = 0;
-       }
-       for (i = 0; i < dh->prime_len - 1; i++) {
-               if (ret_priv[i])
-                       break;
-       }
-       if (i == dh->prime_len - 1 && (ret_priv[i] == 0 || ret_priv[i] == 1))
+       if (crypto_dh_init(gen, dh->prime, dh->prime_len, ret_priv,
+                          ret_pub) < 0)
                return -1;
        wpa_hexdump_key(MSG_DEBUG, "EAP-EKE: DH private value",
                        ret_priv, dh->prime_len);
-
-       /* y = g ^ x (mod p) */
-       pub_len = dh->prime_len;
-       if (crypto_mod_exp(&gen, 1, ret_priv, dh->prime_len,
-                          dh->prime, dh->prime_len, ret_pub, &pub_len) < 0)
-               return -1;
-       if (pub_len < dh->prime_len) {
-               size_t pad = dh->prime_len - pub_len;
-               os_memmove(ret_pub + pad, ret_pub, pub_len);
-               os_memset(ret_pub, 0, pad);
-       }
-
        wpa_hexdump(MSG_DEBUG, "EAP-EKE: DH public value",
                    ret_pub, dh->prime_len);
 
@@ -421,8 +398,9 @@ int eap_eke_shared_secret(struct eap_eke_session *sess, const u8 *key,
 
        /* SharedSecret = prf(0+, g ^ (x_s * x_p) (mod p)) */
        len = dh->prime_len;
-       if (crypto_mod_exp(peer_pub, dh->prime_len, dhpriv, dh->prime_len,
-                          dh->prime, dh->prime_len, modexp, &len) < 0)
+       if (crypto_dh_derive_secret(*dh->generator, dh->prime, dh->prime_len,
+                                   dhpriv, dh->prime_len, peer_pub,
+                                   dh->prime_len, modexp, &len) < 0)
                return -1;
        if (len < dh->prime_len) {
                size_t pad = dh->prime_len - len;