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DPP: Use crypto.h for authentication computation

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Rewrite dpp_auth_derive_l_responder/initiator() using EC point/bignum
primitives defined in crypto.h API.

Signed-off-by: Cedric Izoard <cedric.izoard@ceva-dsp.com>
This commit is contained in:
Cedric Izoard 2021-06-28 18:25:30 +02:00 committed by Jouni Malinen
parent 0d1d74107b
commit 4767de3a42
1 changed files with 47 additions and 86 deletions
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133
src/common/dpp_crypto.c
View file

@ -1314,122 +1314,83 @@ fail:
int dpp_auth_derive_l_responder(struct dpp_authentication *auth)
{
const EC_GROUP *group;
EC_POINT *l = NULL;
const EC_KEY *BI, *bR, *pR;
const EC_POINT *BI_point;
BN_CTX *bnctx;
BIGNUM *lx, *sum, *q;
const BIGNUM *bR_bn, *pR_bn;
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;
int ret = -1;
/* L = ((bR + pR) modulo q) * BI */
bnctx = BN_CTX_new();
sum = BN_new();
q = BN_new();
lx = BN_new();
if (!bnctx || !sum || !q || !lx)
goto fail;
BI = EVP_PKEY_get0_EC_KEY((EVP_PKEY *) auth->peer_bi->pubkey);
if (!BI)
goto fail;
BI_point = EC_KEY_get0_public_key(BI);
group = EC_KEY_get0_group(BI);
if (!group)
ec = crypto_ec_init(crypto_ec_key_group(auth->peer_bi->pubkey));
if (!ec)
goto fail;
bR = EVP_PKEY_get0_EC_KEY((EVP_PKEY *) auth->own_bi->pubkey);
pR = EVP_PKEY_get0_EC_KEY((EVP_PKEY *) auth->own_protocol_key);
if (!bR || !pR)
q = crypto_ec_get_order(ec);
BI = crypto_ec_key_get_public_key(auth->peer_bi->pubkey);
bR = crypto_ec_key_get_private_key(auth->own_bi->pubkey);
pR = crypto_ec_key_get_private_key(auth->own_protocol_key);
sum = crypto_bignum_init();
L = crypto_ec_point_init(ec);
lx = crypto_bignum_init();
if (!q || !BI || !bR || !pR || !sum || !L || !lx ||
crypto_bignum_addmod(bR, pR, q, sum) ||
crypto_ec_point_mul(ec, BI, sum, L) ||
crypto_ec_point_x(ec, L, lx) ||
crypto_bignum_to_bin(lx, auth->Lx, sizeof(auth->Lx),
auth->secret_len) < 0)
goto fail;
bR_bn = EC_KEY_get0_private_key(bR);
pR_bn = EC_KEY_get0_private_key(pR);
if (!bR_bn || !pR_bn)
goto fail;
if (EC_GROUP_get_order(group, q, bnctx) != 1 ||
BN_mod_add(sum, bR_bn, pR_bn, q, bnctx) != 1)
goto fail;
l = EC_POINT_new(group);
if (!l ||
EC_POINT_mul(group, l, NULL, BI_point, sum, bnctx) != 1 ||
EC_POINT_get_affine_coordinates_GFp(group, l, lx, NULL,
bnctx) != 1) {
wpa_printf(MSG_ERROR,
"OpenSSL: failed: %s",
ERR_error_string(ERR_get_error(), NULL));
goto fail;
}
if (dpp_bn2bin_pad(lx, auth->Lx, auth->secret_len) < 0)
goto fail;
wpa_hexdump_key(MSG_DEBUG, "DPP: L.x", auth->Lx, auth->secret_len);
auth->Lx_len = auth->secret_len;
ret = 0;
fail:
EC_POINT_clear_free(l);
BN_clear_free(lx);
BN_clear_free(sum);
BN_free(q);
BN_CTX_free(bnctx);
crypto_bignum_deinit(lx, 1);
crypto_bignum_deinit(sum, 1);
crypto_ec_point_deinit(L, 1);
crypto_ec_deinit(ec);
return ret;
}
int dpp_auth_derive_l_initiator(struct dpp_authentication *auth)
{
const EC_GROUP *group;
EC_POINT *l = NULL, *sum = NULL;
const EC_KEY *bI, *BR, *PR;
const EC_POINT *BR_point, *PR_point;
BN_CTX *bnctx;
BIGNUM *lx;
const BIGNUM *bI_bn;
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;
int ret = -1;
/* L = bI * (BR + PR) */
bnctx = BN_CTX_new();
lx = BN_new();
if (!bnctx || !lx)
ec = crypto_ec_init(crypto_ec_key_group(auth->peer_bi->pubkey));
if (!ec)
goto fail;
BR = EVP_PKEY_get0_EC_KEY((EVP_PKEY *) auth->peer_bi->pubkey);
PR = EVP_PKEY_get0_EC_KEY((EVP_PKEY *) auth->peer_protocol_key);
if (!BR || !PR)
goto fail;
BR_point = EC_KEY_get0_public_key(BR);
PR_point = EC_KEY_get0_public_key(PR);
bI = EVP_PKEY_get0_EC_KEY((EVP_PKEY *) auth->own_bi->pubkey);
if (!bI)
BR = crypto_ec_key_get_public_key(auth->peer_bi->pubkey);
PR = crypto_ec_key_get_public_key(auth->peer_protocol_key);
bI = crypto_ec_key_get_private_key(auth->own_bi->pubkey);
sum = crypto_ec_point_init(ec);
L = crypto_ec_point_init(ec);
lx = crypto_bignum_init();
if (!BR || !PR || !bI || !sum || !L || !lx ||
crypto_ec_point_add(ec, BR, PR, sum) ||
crypto_ec_point_mul(ec, sum, bI, L) ||
crypto_ec_point_x(ec, L, lx) ||
crypto_bignum_to_bin(lx, auth->Lx, sizeof(auth->Lx),
auth->secret_len) < 0)
goto fail;
group = EC_KEY_get0_group(bI);
bI_bn = EC_KEY_get0_private_key(bI);
if (!group || !bI_bn)
goto fail;
sum = EC_POINT_new(group);
l = EC_POINT_new(group);
if (!sum || !l ||
EC_POINT_add(group, sum, BR_point, PR_point, bnctx) != 1 ||
EC_POINT_mul(group, l, NULL, sum, bI_bn, bnctx) != 1 ||
EC_POINT_get_affine_coordinates_GFp(group, l, lx, NULL,
bnctx) != 1) {
wpa_printf(MSG_ERROR,
"OpenSSL: failed: %s",
ERR_error_string(ERR_get_error(), NULL));
goto fail;
}
if (dpp_bn2bin_pad(lx, auth->Lx, auth->secret_len) < 0)
goto fail;
wpa_hexdump_key(MSG_DEBUG, "DPP: L.x", auth->Lx, auth->secret_len);
auth->Lx_len = auth->secret_len;
ret = 0;
fail:
EC_POINT_clear_free(l);
EC_POINT_clear_free(sum);
BN_clear_free(lx);
BN_CTX_free(bnctx);
crypto_bignum_deinit(lx, 1);
crypto_ec_point_deinit(sum, 1);
crypto_ec_point_deinit(L, 1);
crypto_ec_deinit(ec);
return ret;
}