From patchwork Tue Sep 26 09:46:41 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Lukas Wunner X-Patchwork-Id: 726479 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id EC95FE7D273 for ; Tue, 26 Sep 2023 09:55:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231760AbjIZJzP (ORCPT ); Tue, 26 Sep 2023 05:55:15 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41580 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230037AbjIZJzM (ORCPT ); Tue, 26 Sep 2023 05:55:12 -0400 X-Greylist: delayed 501 seconds by postgrey-1.37 at lindbergh.monkeyblade.net; Tue, 26 Sep 2023 02:55:05 PDT Received: from bmailout2.hostsharing.net (bmailout2.hostsharing.net [83.223.78.240]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8E486B3; Tue, 26 Sep 2023 02:55:05 -0700 (PDT) Received: from h08.hostsharing.net (h08.hostsharing.net [IPv6:2a01:37:1000::53df:5f1c:0]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256 client-signature RSA-PSS (4096 bits) client-digest SHA256) (Client CN "*.hostsharing.net", Issuer "RapidSSL Global TLS RSA4096 SHA256 2022 CA1" (verified OK)) by bmailout2.hostsharing.net (Postfix) with ESMTPS id 7A6762800BBE7; Tue, 26 Sep 2023 11:46:40 +0200 (CEST) Received: by h08.hostsharing.net (Postfix, from userid 100393) id 688211F230; Tue, 26 Sep 2023 11:46:40 +0200 (CEST) Message-Id: From: Lukas Wunner Date: Tue, 26 Sep 2023 11:46:41 +0200 Subject: [PATCH] X.509: Add missing IMPLICIT annotations to AKID ASN.1 module To: David Howells , Herbert Xu , "David S. Miller" Cc: Vivek Goyal , keyrings@vger.kernel.org, linux-crypto@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-crypto@vger.kernel.org The ASN.1 module in RFC 5280 appendix A.1 uses EXPLICIT TAGS whereas the one in appendix A.2 uses IMPLICIT TAGS. The kernel's simplified asn1_compiler.c always uses EXPLICIT TAGS, hence definitions from appendix A.2 need to be annotated as IMPLICIT for the compiler to generate RFC-compliant code. In particular, GeneralName is defined in appendix A.2: GeneralName ::= CHOICE { otherName [0] OtherName, ... dNSName [2] IA5String, x400Address [3] ORAddress, directoryName [4] Name, ... } Because appendix A.2 uses IMPLICIT TAGS, the IA5String tag (0x16) of a dNSName is not rendered. Instead, the string directly succeeds the [2] tag (0x82). Likewise, the SEQUENCE tag (0x30) of an OtherName is not rendered. Instead, only the constituents of the SEQUENCE are rendered: An OID tag (0x06), a [0] tag (0xa0) and an ANY tag. That's three consecutive tags instead of a single encompassing tag. The situation is different for x400Address and directoryName choices: They reference ORAddress and Name, which are defined in appendix A.1, therefore use EXPLICIT TAGS. The AKID ASN.1 module is missing several IMPLICIT annotations, hence isn't RFC-compliant. In the unlikely event that an AKID contains other elements beside a directoryName, users may see parse errors. Add the missing annotations but do not tag this commit for stable as I am not aware of any issue reports. Fixes are only eligible for stable if they're "obviously correct" and with ASN.1 there's no such thing. Signed-off-by: Lukas Wunner --- Found this while bringing up PCI device authentication, which involves validating the Subject Alternative Name in certificates. I double-checked all ASN.1 modules in the tree and this seems to be the only one affected by the issue. crypto/asymmetric_keys/x509_akid.asn1 | 24 +++++++++++++++++------- 1 file changed, 17 insertions(+), 7 deletions(-) diff --git a/crypto/asymmetric_keys/x509_akid.asn1 b/crypto/asymmetric_keys/x509_akid.asn1 index 1a33231..c7818ff 100644 --- a/crypto/asymmetric_keys/x509_akid.asn1 +++ b/crypto/asymmetric_keys/x509_akid.asn1 @@ -14,15 +14,15 @@ CertificateSerialNumber ::= INTEGER ({ x509_akid_note_serial }) GeneralNames ::= SEQUENCE OF GeneralName GeneralName ::= CHOICE { - otherName [0] ANY, - rfc822Name [1] IA5String, - dNSName [2] IA5String, + otherName [0] IMPLICIT OtherName, + rfc822Name [1] IMPLICIT IA5String, + dNSName [2] IMPLICIT IA5String, x400Address [3] ANY, directoryName [4] Name ({ x509_akid_note_name }), - ediPartyName [5] ANY, - uniformResourceIdentifier [6] IA5String, - iPAddress [7] OCTET STRING, - registeredID [8] OBJECT IDENTIFIER + ediPartyName [5] IMPLICIT EDIPartyName, + uniformResourceIdentifier [6] IMPLICIT IA5String, + iPAddress [7] IMPLICIT OCTET STRING, + registeredID [8] IMPLICIT OBJECT IDENTIFIER } Name ::= SEQUENCE OF RelativeDistinguishedName @@ -33,3 +33,13 @@ AttributeValueAssertion ::= SEQUENCE { attributeType OBJECT IDENTIFIER ({ x509_note_OID }), attributeValue ANY ({ x509_extract_name_segment }) } + +OtherName ::= SEQUENCE { + type-id OBJECT IDENTIFIER, + value [0] ANY + } + +EDIPartyName ::= SEQUENCE { + nameAssigner [0] ANY OPTIONAL, + partyName [1] ANY + }