From: Tomas Mraz Date: Mon, 5 Aug 2024 15:54:14 +0000 (+0200) Subject: dh_kmgmt.c: Avoid expensive public key validation for known safe-prime groups X-Git-Tag: openssl-3.4.0-alpha1~194 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=e70e34d857d4003199bcb5d3b52ca8102ccc1b98;p=thirdparty%2Fopenssl.git dh_kmgmt.c: Avoid expensive public key validation for known safe-prime groups The partial validation is fully sufficient to check the key validity. Thanks to Szilárd Pfeiffer for reporting the issue. Reviewed-by: Neil Horman Reviewed-by: Matt Caswell Reviewed-by: Paul Dale (Merged from https://github.com/openssl/openssl/pull/25088) --- diff --git a/providers/implementations/keymgmt/dh_kmgmt.c b/providers/implementations/keymgmt/dh_kmgmt.c index 82c3093b122..ebdce767102 100644 --- a/providers/implementations/keymgmt/dh_kmgmt.c +++ b/providers/implementations/keymgmt/dh_kmgmt.c @@ -388,9 +388,11 @@ static int dh_validate_public(const DH *dh, int checktype) if (pub_key == NULL) return 0; - /* The partial test is only valid for named group's with q = (p - 1) / 2 */ - if (checktype == OSSL_KEYMGMT_VALIDATE_QUICK_CHECK - && ossl_dh_is_named_safe_prime_group(dh)) + /* + * The partial test is only valid for named group's with q = (p - 1) / 2 + * but for that case it is also fully sufficient to check the key validity. + */ + if (ossl_dh_is_named_safe_prime_group(dh)) return ossl_dh_check_pub_key_partial(dh, pub_key, &res); return DH_check_pub_key_ex(dh, pub_key);