crypto: Convert crypto_ec_key_get_private_key() to return new bignum

This makes it easier for the crypto library/wrapper to avoid direct
references to internal EC key parameters.

Signed-off-by: Jouni Malinen <j@w1.fi>

diff --git a/src/common/dpp_crypto.c b/src/common/dpp_crypto.c
index 8d3f3abfa6ae76415df81a3da5633b2a7d1ae069..2696dd226272763123aa9f3ed8da97e0a789eda7 100644 (file)
--- a/src/common/dpp_crypto.c
+++ b/src/common/dpp_crypto.c
@@ -1037,8 +1037,8 @@ int dpp_auth_derive_l_responder(struct dpp_authentication *auth)
        struct crypto_ec *ec;
        struct crypto_ec_point *L = NULL;
        const struct crypto_ec_point *BI;
-       const struct crypto_bignum *bR, *pR, *q;
-       struct crypto_bignum *sum = NULL, *lx = NULL;
+       const struct crypto_bignum *q;
+       struct crypto_bignum *sum = NULL, *lx = NULL, *bR = NULL, *pR = NULL;
        int ret = -1;
 
        /* L = ((bR + pR) modulo q) * BI */
@@ -1068,6 +1068,8 @@ int dpp_auth_derive_l_responder(struct dpp_authentication *auth)
 fail:
        crypto_bignum_deinit(lx, 1);
        crypto_bignum_deinit(sum, 1);
+       crypto_bignum_deinit(bR, 1);
+       crypto_bignum_deinit(pR, 1);
        crypto_ec_point_deinit(L, 1);
        crypto_ec_deinit(ec);
        return ret;
@@ -1079,8 +1081,7 @@ int dpp_auth_derive_l_initiator(struct dpp_authentication *auth)
        struct crypto_ec *ec;
        struct crypto_ec_point *L = NULL, *sum = NULL;
        const struct crypto_ec_point *BR, *PR;
-       const struct crypto_bignum *bI;
-       struct crypto_bignum *lx = NULL;
+       struct crypto_bignum *lx = NULL, *bI = NULL;
        int ret = -1;
 
        /* L = bI * (BR + PR) */
@@ -1108,6 +1109,7 @@ int dpp_auth_derive_l_initiator(struct dpp_authentication *auth)
        ret = 0;
 fail:
        crypto_bignum_deinit(lx, 1);
+       crypto_bignum_deinit(bI, 1);
        crypto_ec_point_deinit(sum, 1);
        crypto_ec_point_deinit(L, 1);
        crypto_ec_deinit(ec);
@@ -1661,8 +1663,8 @@ int dpp_reconfig_derive_ke_responder(struct dpp_authentication *auth,
                                     struct json_token *peer_net_access_key)
 {
        struct crypto_ec_key *own_key = NULL, *peer_key = NULL;
-       struct crypto_bignum *sum = NULL;
-       const struct crypto_bignum *q, *cR, *pR;
+       struct crypto_bignum *sum = NULL, *cR = NULL, *pR = NULL;
+       const struct crypto_bignum *q;
        struct crypto_ec *ec = NULL;
        struct crypto_ec_point *M = NULL;
        const struct crypto_ec_point *CI;
@@ -1749,6 +1751,8 @@ fail:
        forced_memzero(Mx, sizeof(Mx));
        crypto_ec_point_deinit(M, 1);
        crypto_bignum_deinit(sum, 1);
+       crypto_bignum_deinit(cR, 1);
+       crypto_bignum_deinit(pR, 1);
        crypto_ec_key_deinit(own_key);
        crypto_ec_key_deinit(peer_key);
        crypto_ec_deinit(ec);
@@ -1762,7 +1766,7 @@ int dpp_reconfig_derive_ke_initiator(struct dpp_authentication *auth,
 {
        struct crypto_ec_key *pr = NULL, *peer_key = NULL;
        const struct crypto_ec_point *CR, *PR;
-       const struct crypto_bignum *cI;
+       struct crypto_bignum *cI = NULL;
        struct crypto_ec *ec = NULL;
        struct crypto_ec_point *sum = NULL, *M = NULL;
        u8 Mx[DPP_MAX_SHARED_SECRET_LEN];
@@ -1835,6 +1839,7 @@ int dpp_reconfig_derive_ke_initiator(struct dpp_authentication *auth,
 fail:
        forced_memzero(prk, sizeof(prk));
        forced_memzero(Mx, sizeof(Mx));
+       crypto_bignum_deinit(cI, 1);
        crypto_ec_key_deinit(pr);
        crypto_ec_key_deinit(peer_key);
        crypto_ec_point_deinit(sum, 1);
@@ -2321,7 +2326,7 @@ struct crypto_ec_point * dpp_decrypt_e_id(struct crypto_ec_key *ppkey,
                                          struct crypto_ec_key *e_prime_id)
 {
        struct crypto_ec *ec;
-       const struct crypto_bignum *pp;
+       struct crypto_bignum *pp = NULL;
        struct crypto_ec_point *e_id = NULL;
        const struct crypto_ec_point *a_nonce_point, *e_prime_id_point;
 
@@ -2348,6 +2353,7 @@ struct crypto_ec_point * dpp_decrypt_e_id(struct crypto_ec_key *ppkey,
        crypto_ec_point_debug_print(ec, e_id, "DPP: Decrypted E-id");
 
 fail:
+       crypto_bignum_deinit(pp, 1);
        crypto_ec_deinit(ec);
        return e_id;
 }

diff --git a/src/crypto/crypto.h b/src/crypto/crypto.h
index e4f3eb3e619fcc391879774c3532afc8ebdc2db9..730ad0d58fc55db428e60836d1dc780ea8bc85c6 100644 (file)
--- a/src/crypto/crypto.h
+++ b/src/crypto/crypto.h
@@ -1094,8 +1094,10 @@ crypto_ec_key_get_public_key(struct crypto_ec_key *key);
  * crypto_ec_key_get_private_key - Get EC private key as a bignum
  * @key: EC key from crypto_ec_key_parse/set_pub() or crypto_ec_key_parse_priv()
  * Returns: Private key as a bignum or %NULL on failure
+ *
+ * The caller needs to free the returned value with crypto_bignum_deinit().
  */
-const struct crypto_bignum *
+struct crypto_bignum *
 crypto_ec_key_get_private_key(struct crypto_ec_key *key);
 
 /**

diff --git a/src/crypto/crypto_openssl.c b/src/crypto/crypto_openssl.c
index 212e5adad5d3fa687c483a03c2ea50c622fe395b..3a6b876828c18b22e775bb8a18e6e6daf8e098d2 100644 (file)
--- a/src/crypto/crypto_openssl.c
+++ b/src/crypto/crypto_openssl.c
@@ -3425,15 +3425,20 @@ crypto_ec_key_get_public_key(struct crypto_ec_key *key)
 }
 
 
-const struct crypto_bignum *
+struct crypto_bignum *
 crypto_ec_key_get_private_key(struct crypto_ec_key *key)
 {
+       EVP_PKEY *pkey = (EVP_PKEY *) key;
        const EC_KEY *eckey;
+       const BIGNUM *bn;
 
-       eckey = EVP_PKEY_get0_EC_KEY((EVP_PKEY *) key);
+       eckey = EVP_PKEY_get0_EC_KEY(pkey);
        if (!eckey)
                return NULL;
-       return (const struct crypto_bignum *) EC_KEY_get0_private_key(eckey);
+       bn = EC_KEY_get0_private_key(eckey);
+       if (!bn)
+               return NULL;
+       return (struct crypto_bignum *) BN_dup(bn);
 }