From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.9]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 8E07FD534 for ; Tue, 3 Oct 2023 08:31:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1696321890; x=1727857890; h=date:from:to:cc:subject:in-reply-to:message-id: references:mime-version; bh=xvRTEJgiLM4R8J7f3Dw6MhEmiMJyQfp7liKkGIGPBHQ=; b=K8kecCG6UbdxMZE7sOI68jcF3v0627ke+xSBVBvxH+dRbT91UFRLTcSo UmpLpkaVvXR8qwjFMkDk+/BXfPxAC5d4sWK/fEVF/5e3w4g/is4PP3tts DtIRDDUJ+GryzJMmJX7nNIDo6mdl5qN+6VRQorB1ifng1VPMil5XJ15J+ Kzvz6veOGc3/VMv1LhWtYe1/BQIMg7pyRQkLoR1I8Q22+FZbBj8EPRYvC 8K0baZnMumb8qYhwCEv70rF3CHMWT2ytHJPM2QyFwYPSjmTaOdO+p90jE NqGuQtAPfR01qsDBLvZ7aLO+rvE47TVGP5ZIUtBhMoCZ36bq0j+pyZnch w==; X-IronPort-AV: E=McAfee;i="6600,9927,10851"; a="1413572" X-IronPort-AV: E=Sophos;i="6.03,196,1694761200"; d="scan'208";a="1413572" Received: from orsmga004.jf.intel.com ([10.7.209.38]) by orvoesa101.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 03 Oct 2023 01:31:29 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10851"; a="874639937" X-IronPort-AV: E=Sophos;i="6.03,196,1694761200"; d="scan'208";a="874639937" Received: from tciutacu-mobl.ger.corp.intel.com (HELO rrabie-mobl.amr.corp.intel.com) ([10.252.40.114]) by orsmga004-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 03 Oct 2023 01:31:22 -0700 Date: Tue, 3 Oct 2023 11:31:20 +0300 (EEST) From: =?ISO-8859-15?Q?Ilpo_J=E4rvinen?= To: Lukas Wunner cc: Bjorn Helgaas , David Howells , David Woodhouse , Herbert Xu , "David S. Miller" , Alex Williamson , linux-pci@vger.kernel.org, linux-cxl@vger.kernel.org, linux-coco@lists.linux.dev, keyrings@vger.kernel.org, linux-crypto@vger.kernel.org, kvm@vger.kernel.org, Jonathan Cameron , linuxarm@huawei.com, David Box , Dan Williams , Dave Jiang , "Li, Ming" , Zhi Wang , Alistair Francis , Wilfred Mallawa , Alexey Kardashevskiy , Tom Lendacky , Sean Christopherson , Alexander Graf Subject: Re: [PATCH 03/12] X.509: Move certificate length retrieval into new helper In-Reply-To: <16c06528d13b2c0081229a45cacd4b1b9cdff738.1695921657.git.lukas@wunner.de> Message-ID: <76259143-d07e-e042-73a1-677094211361@linux.intel.com> References: <16c06528d13b2c0081229a45cacd4b1b9cdff738.1695921657.git.lukas@wunner.de> Precedence: bulk X-Mailing-List: linux-coco@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII On Thu, 28 Sep 2023, Lukas Wunner wrote: > The upcoming in-kernel SPDM library (Security Protocol and Data Model, > https://www.dmtf.org/dsp/DSP0274) needs to retrieve the length from > ASN.1 DER-encoded X.509 certificates. > > Such code already exists in x509_load_certificate_list(), so move it > into a new helper for reuse by SPDM. > > No functional change intended. > > Signed-off-by: Lukas Wunner > --- > crypto/asymmetric_keys/x509_loader.c | 38 +++++++++++++++++++--------- > include/keys/asymmetric-type.h | 2 ++ > 2 files changed, 28 insertions(+), 12 deletions(-) > > diff --git a/crypto/asymmetric_keys/x509_loader.c b/crypto/asymmetric_keys/x509_loader.c > index a41741326998..121460a0de46 100644 > --- a/crypto/asymmetric_keys/x509_loader.c > +++ b/crypto/asymmetric_keys/x509_loader.c > @@ -4,28 +4,42 @@ > #include > #include > > +int x509_get_certificate_length(const u8 *p, unsigned long buflen) Make the return type ssize_t. unsigned long -> size_t buflen (or perhaps ssize_t if you want to compare below to have the same signedness). > +{ > + int plen; ssize_t > + > + /* Each cert begins with an ASN.1 SEQUENCE tag and must be more > + * than 256 bytes in size. > + */ > + if (buflen < 4) > + return -EINVAL; > + > + if (p[0] != 0x30 && > + p[1] != 0x82) > + return -EINVAL; > + > + plen = (p[2] << 8) | p[3]; > + plen += 4; > + if (plen > buflen) > + return -EINVAL; > + > + return plen; > +} > +EXPORT_SYMBOL_GPL(x509_get_certificate_length); > + > int x509_load_certificate_list(const u8 cert_list[], > const unsigned long list_size, > const struct key *keyring) > { > key_ref_t key; > const u8 *p, *end; > - size_t plen; > + int plen; ssize_t plen. -- i. > > p = cert_list; > end = p + list_size; > while (p < end) { > - /* Each cert begins with an ASN.1 SEQUENCE tag and must be more > - * than 256 bytes in size. > - */ > - if (end - p < 4) > - goto dodgy_cert; > - if (p[0] != 0x30 && > - p[1] != 0x82) > - goto dodgy_cert; > - plen = (p[2] << 8) | p[3]; > - plen += 4; > - if (plen > end - p) > + plen = x509_get_certificate_length(p, end - p); > + if (plen < 0) > goto dodgy_cert; > > key = key_create_or_update(make_key_ref(keyring, 1), > diff --git a/include/keys/asymmetric-type.h b/include/keys/asymmetric-type.h > index 69a13e1e5b2e..6705cfde25b9 100644 > --- a/include/keys/asymmetric-type.h > +++ b/include/keys/asymmetric-type.h > @@ -84,6 +84,8 @@ extern struct key *find_asymmetric_key(struct key *keyring, > const struct asymmetric_key_id *id_2, > bool partial); > > +int x509_get_certificate_length(const u8 *p, unsigned long buflen); > + > int x509_load_certificate_list(const u8 cert_list[], const unsigned long list_size, > const struct key *keyring); > >