From: Alexander Holler Subject: [PATCH] crypto: Ignore validity dates of X.509 certificates at loading/parsing time Date: Wed, 27 Mar 2013 19:41:50 +0100 Message-ID: <1364409710-6458-1-git-send-email-holler@ahsoftware.de> Cc: linux-crypto@vger.kernel.org, Herbert Xu , "David S. Miller" , Rusty Russell , David Howells , Josh Boyer , David Woodhouse , Alexander Holler , stable@vger.kernel.org To: linux-kernel@vger.kernel.org Return-path: Received: from h1446028.stratoserver.net ([85.214.92.142]:43627 "EHLO mail.ahsoftware.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752930Ab3C0Sm1 (ORCPT ); Wed, 27 Mar 2013 14:42:27 -0400 Sender: linux-crypto-owner@vger.kernel.org List-ID: I don't see any real use case where checking the validity dates of X.509 certificates at parsing time adds any security gain. In contrast, doing so makes MODSIGN unusable on systems without a RTC (or systems with a possible wrong date in a existing RTC, or systems where the RTC is read after the keys got loaded). If something really cares about the dates, it should check them at the time when the certificates are used, not when they are loaded and parsed. So just remove the validity check of the dates in the parser. Signed-off-by: Alexander Holler Cc: stable@vger.kernel.org Sidenote (not for necessarily for inclusion into the patch): There were already 3 variations of this patch. The first removed the check by adding a config option: https://lkml.org/lkml/2013/2/25/171 The second just removed the return of errors: https://lkml.org/lkml/2013/3/14/247 And the third wich removed parsing of the dates too: https://lkml.org/lkml/2013/3/14/257 Maybe this one will find the approval of a maintainer. Here is a thread which explains the motivation for this patch a bit further: https://lkml.org/lkml/2013/2/13/90 --- crypto/asymmetric_keys/x509_public_key.c | 38 -------------------------------- 1 file changed, 38 deletions(-) diff --git a/crypto/asymmetric_keys/x509_public_key.c b/crypto/asymmetric_keys/x509_public_key.c index 06007f0..52222a2 100644 --- a/crypto/asymmetric_keys/x509_public_key.c +++ b/crypto/asymmetric_keys/x509_public_key.c @@ -106,7 +106,6 @@ error_no_sig: static int x509_key_preparse(struct key_preparsed_payload *prep) { struct x509_certificate *cert; - struct tm now; size_t srlen, sulen; char *desc = NULL; int ret; @@ -137,43 +136,6 @@ static int x509_key_preparse(struct key_preparsed_payload *prep) goto error_free_cert; } - time_to_tm(CURRENT_TIME.tv_sec, 0, &now); - pr_devel("Now: %04ld-%02d-%02d %02d:%02d:%02d\n", - now.tm_year + 1900, now.tm_mon + 1, now.tm_mday, - now.tm_hour, now.tm_min, now.tm_sec); - if (now.tm_year < cert->valid_from.tm_year || - (now.tm_year == cert->valid_from.tm_year && - (now.tm_mon < cert->valid_from.tm_mon || - (now.tm_mon == cert->valid_from.tm_mon && - (now.tm_mday < cert->valid_from.tm_mday || - (now.tm_mday == cert->valid_from.tm_mday && - (now.tm_hour < cert->valid_from.tm_hour || - (now.tm_hour == cert->valid_from.tm_hour && - (now.tm_min < cert->valid_from.tm_min || - (now.tm_min == cert->valid_from.tm_min && - (now.tm_sec < cert->valid_from.tm_sec - ))))))))))) { - pr_warn("Cert %s is not yet valid\n", cert->fingerprint); - ret = -EKEYREJECTED; - goto error_free_cert; - } - if (now.tm_year > cert->valid_to.tm_year || - (now.tm_year == cert->valid_to.tm_year && - (now.tm_mon > cert->valid_to.tm_mon || - (now.tm_mon == cert->valid_to.tm_mon && - (now.tm_mday > cert->valid_to.tm_mday || - (now.tm_mday == cert->valid_to.tm_mday && - (now.tm_hour > cert->valid_to.tm_hour || - (now.tm_hour == cert->valid_to.tm_hour && - (now.tm_min > cert->valid_to.tm_min || - (now.tm_min == cert->valid_to.tm_min && - (now.tm_sec > cert->valid_to.tm_sec - ))))))))))) { - pr_warn("Cert %s has expired\n", cert->fingerprint); - ret = -EKEYEXPIRED; - goto error_free_cert; - } - cert->pub->algo = x509_public_key_algorithms[cert->pkey_algo]; cert->pub->id_type = PKEY_ID_X509; -- 1.8.1.4