From: lizhi <lizhi206@huawei.com> To ensure consistency with the results of openssl software calculations, pad the high bits of shared keys that are shorter than the standard length with 0. Signed-off-by: lizhi <lizhi206@huawei.com> Signed-off-by: JiangShui Yang <yangjiangshui@h-partners.com> --- src/uadk_ec.c | 15 +++++++++++++-- 1 file changed, 13 insertions(+), 2 deletions(-) diff --git a/src/uadk_ec.c b/src/uadk_ec.c index 22695d4..6b4cdc6 100644 --- a/src/uadk_ec.c +++ b/src/uadk_ec.c @@ -1182,6 +1182,9 @@ static int ecdh_get_shared_key(const EC_KEY *ecdh, struct wd_ecc_req *req) { struct wd_ecc_point *shared_key = NULL; + const EC_GROUP *group; + size_t key_size_std; + size_t len; wd_ecxdh_get_out_params(req->dst, &shared_key); if (!shared_key) { @@ -1189,8 +1192,15 @@ static int ecdh_get_shared_key(const EC_KEY *ecdh, return 0; } - *outlen = shared_key->x.dsize; + group = EC_KEY_get0_group(ecdh); + key_size_std = (size_t)(EC_GROUP_get_degree(group) + + UADK_ECC_PADDING) >> TRANS_BITS_BYTES_SHIFT; + if (unlikely(key_size_std > UADK_ECC_MAX_KEY_BYTES || key_size_std == 0)) { + fprintf(stderr, "failed to get the proper filed size %zu\n", key_size_std); + return 0; + } + *outlen = key_size_std; *out = OPENSSL_zalloc(*outlen); if (!*out) { fprintf(stderr, "failed to alloc output key, outlen = %zu\n", @@ -1198,7 +1208,8 @@ static int ecdh_get_shared_key(const EC_KEY *ecdh, return 0; } - memcpy(*out, (unsigned char *)shared_key->x.data, *outlen); + len = key_size_std < shared_key->x.dsize ? key_size_std : shared_key->x.dsize; + memcpy(*out + *outlen - len, shared_key->x.data, len); return 1; } -- 2.33.0