From nobody Mon Feb 9 12:01:53 2026 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) (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 1D56832C929 for ; Thu, 15 Jan 2026 21:51:44 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.133.124 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768513912; cv=none; b=iMQHPfrEErFxCQvL9sxz5fXjrvti1zr7E/Vxey185aTgT8t2VjhwjWmqN8SiMtKmmyDnDhqyRu8k0uppDNxdrvjIzH1A2g2Gyl3HmOsQ+71j++lUzwBbsQzcqQjwtyOnWrDs51UIydwSt1NpcioYvpUzFEWm5bqzc5aV2ECb3ZA= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768513912; c=relaxed/simple; bh=YylhoP6IJY35PuqvuKayPKjWUAwRiqx3b9zzCyG5wd4=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=i+3xrvAN2I9xunOZ+P6H8oOxmGfg9O5zlNSOIONCa73UXyFBn8ARNnNBDZhomJHqzx9do4ZEWtO+O9HTXbff13uwk5pS7jkFiQcdo2N5pIBbwiYltPqhOIDrnrWwz47avil2xNocmv3KhDKQ394vVY440bVgfNqSQ2UbwPZEOL4= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com; spf=pass smtp.mailfrom=redhat.com; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b=VTaTzOSo; arc=none smtp.client-ip=170.10.133.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=redhat.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="VTaTzOSo" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1768513904; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=cq95vFxe+E/azapPIGqLH7kDJ2ZslBJUYrt2YlEskHU=; b=VTaTzOSoWIOdh0J1g+WdaXHo1aEdfhlxicIEAdFWX+C6NSJz+itYlB7heDAu3OQJYDQbBk lGrZTYaTHhmKIpm7ru/3JbW4dP/H8WloTiDHN3ymUQKAU4Hs1wNBrbSeakO+NGidhVFa6i mtno2xFC0+j0lMXpS66/kFg1rwaO5K8= Received: from mx-prod-mc-03.mail-002.prod.us-west-2.aws.redhat.com (ec2-54-186-198-63.us-west-2.compute.amazonaws.com [54.186.198.63]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-610-4p02CpYwOWS9c9ynieqbaw-1; Thu, 15 Jan 2026 16:51:38 -0500 X-MC-Unique: 4p02CpYwOWS9c9ynieqbaw-1 X-Mimecast-MFC-AGG-ID: 4p02CpYwOWS9c9ynieqbaw_1768513896 Received: from mx-prod-int-06.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-06.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.93]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-03.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 6B4D51956059; Thu, 15 Jan 2026 21:51:36 +0000 (UTC) Received: from warthog.procyon.org.uk.com (unknown [10.42.28.4]) by mx-prod-int-06.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTP id B04991800665; Thu, 15 Jan 2026 21:51:32 +0000 (UTC) From: David Howells To: Lukas Wunner , Ignat Korchagin Cc: David Howells , Jarkko Sakkinen , Herbert Xu , Eric Biggers , Luis Chamberlain , Petr Pavlu , Daniel Gomez , Sami Tolvanen , "Jason A . Donenfeld" , Ard Biesheuvel , Stephan Mueller , linux-crypto@vger.kernel.org, keyrings@vger.kernel.org, linux-modules@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v12 05/10] modsign: Enable ML-DSA module signing Date: Thu, 15 Jan 2026 21:50:47 +0000 Message-ID: <20260115215100.312611-6-dhowells@redhat.com> In-Reply-To: <20260115215100.312611-1-dhowells@redhat.com> References: <20260115215100.312611-1-dhowells@redhat.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-Scanned-By: MIMEDefang 3.4.1 on 10.30.177.93 Content-Type: text/plain; charset="utf-8" Allow ML-DSA module signing to be enabled. Note that openssl's CMS_*() function suite does not, as of openssl-3.5.1, support the use of CMS_NOATTR with ML-DSA, so the prohibition against using authenticatedAttributes with module signing has to be removed. The selected digest then applies only to the algorithm used to calculate the digest stored in the messageDigest attribute. The ML-DSA algorithm uses its own internal choice of digest (SHAKE256) without regard to what's specified in the CMS message. This is, in theory, configurable, but there's currently no hook in the crypto_sig API to do that, though possibly it could be done by parameterising the name of the algorithm, e.g. ("mldsa87(sha512)"). Signed-off-by: David Howells cc: Eric Biggers cc: Lukas Wunner cc: Ignat Korchagin cc: Stephan Mueller cc: Herbert Xu cc: keyrings@vger.kernel.org cc: linux-crypto@vger.kernel.org --- Documentation/admin-guide/module-signing.rst | 16 +++++---- certs/Kconfig | 21 ++++++++++++ certs/Makefile | 3 ++ crypto/asymmetric_keys/pkcs7_verify.c | 4 --- scripts/sign-file.c | 34 +++++++++++++++----- 5 files changed, 59 insertions(+), 19 deletions(-) diff --git a/Documentation/admin-guide/module-signing.rst b/Documentation/a= dmin-guide/module-signing.rst index a8667a777490..7f2f127dc76f 100644 --- a/Documentation/admin-guide/module-signing.rst +++ b/Documentation/admin-guide/module-signing.rst @@ -28,10 +28,12 @@ trusted userspace bits. =20 This facility uses X.509 ITU-T standard certificates to encode the public = keys involved. The signatures are not themselves encoded in any industrial sta= ndard -type. The built-in facility currently only supports the RSA & NIST P-384 = ECDSA -public key signing standard (though it is pluggable and permits others to = be -used). The possible hash algorithms that can be used are SHA-2 and SHA-3 = of -sizes 256, 384, and 512 (the algorithm is selected by data in the signatur= e). +type. The built-in facility currently only supports the RSA, NIST P-384 E= CDSA +and NIST FIPS-204 ML-DSA public key signing standards (though it is plugga= ble +and permits others to be used). For RSA and ECDSA, the possible hash +algorithms that can be used are SHA-2 and SHA-3 of sizes 256, 384, and 512= (the +algorithm is selected by data in the signature); ML-DSA does its own hashi= ng, +but is allowed to be used with a SHA512 hash for signed attributes. =20 =20 =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D @@ -146,9 +148,9 @@ into vmlinux) using parameters in the:: =20 file (which is also generated if it does not already exist). =20 -One can select between RSA (``MODULE_SIG_KEY_TYPE_RSA``) and ECDSA -(``MODULE_SIG_KEY_TYPE_ECDSA``) to generate either RSA 4k or NIST -P-384 keypair. +One can select between RSA (``MODULE_SIG_KEY_TYPE_RSA``), ECDSA +(``MODULE_SIG_KEY_TYPE_ECDSA``) and ML-DSA (``MODULE_SIG_KEY_TYPE_MLDSA_*`= `) to +generate an RSA 4k, a NIST P-384 keypair or an ML-DSA 44, 65 or 87 keypair. =20 It is strongly recommended that you provide your own x509.genkey file. =20 diff --git a/certs/Kconfig b/certs/Kconfig index 78307dc25559..67a5786423b5 100644 --- a/certs/Kconfig +++ b/certs/Kconfig @@ -39,6 +39,27 @@ config MODULE_SIG_KEY_TYPE_ECDSA Note: Remove all ECDSA signing keys, e.g. certs/signing_key.pem, when falling back to building Linux 5.14 and older kernels. =20 +config MODULE_SIG_KEY_TYPE_MLDSA_44 + bool "ML-DSA-44" + select CRYPTO_MLDSA + help + Use an ML-DSA-44 key (NIST FIPS 204) for module signing + with a SHAKE256 'hash' of the authenticatedAttributes. + +config MODULE_SIG_KEY_TYPE_MLDSA_65 + bool "ML-DSA-65" + select CRYPTO_MLDSA + help + Use an ML-DSA-65 key (NIST FIPS 204) for module signing + with a SHAKE256 'hash' of the authenticatedAttributes. + +config MODULE_SIG_KEY_TYPE_MLDSA_87 + bool "ML-DSA-87" + select CRYPTO_MLDSA + help + Use an ML-DSA-87 key (NIST FIPS 204) for module signing + with a SHAKE256 'hash' of the authenticatedAttributes. + endchoice =20 config SYSTEM_TRUSTED_KEYRING diff --git a/certs/Makefile b/certs/Makefile index f6fa4d8d75e0..3ee1960f9f4a 100644 --- a/certs/Makefile +++ b/certs/Makefile @@ -43,6 +43,9 @@ targets +=3D x509_certificate_list ifeq ($(CONFIG_MODULE_SIG_KEY),certs/signing_key.pem) =20 keytype-$(CONFIG_MODULE_SIG_KEY_TYPE_ECDSA) :=3D -newkey ec -pkeyopt ec_pa= ramgen_curve:secp384r1 +keytype-$(CONFIG_MODULE_SIG_KEY_TYPE_MLDSA_44) :=3D -newkey ml-dsa-44 +keytype-$(CONFIG_MODULE_SIG_KEY_TYPE_MLDSA_65) :=3D -newkey ml-dsa-65 +keytype-$(CONFIG_MODULE_SIG_KEY_TYPE_MLDSA_87) :=3D -newkey ml-dsa-87 =20 quiet_cmd_gen_key =3D GENKEY $@ cmd_gen_key =3D openssl req -new -nodes -utf8 -$(CONFIG_MODULE_SIG_H= ASH) -days 36500 \ diff --git a/crypto/asymmetric_keys/pkcs7_verify.c b/crypto/asymmetric_keys= /pkcs7_verify.c index 46eee9811023..3896e24423f9 100644 --- a/crypto/asymmetric_keys/pkcs7_verify.c +++ b/crypto/asymmetric_keys/pkcs7_verify.c @@ -442,10 +442,6 @@ int pkcs7_verify(struct pkcs7_message *pkcs7, pr_warn("Invalid module sig (not pkcs7-data)\n"); return -EKEYREJECTED; } - if (pkcs7->have_authattrs) { - pr_warn("Invalid module sig (has authattrs)\n"); - return -EKEYREJECTED; - } break; case VERIFYING_FIRMWARE_SIGNATURE: if (pkcs7->data_type !=3D OID_data) { diff --git a/scripts/sign-file.c b/scripts/sign-file.c index 7070245edfc1..547b97097230 100644 --- a/scripts/sign-file.c +++ b/scripts/sign-file.c @@ -315,18 +315,36 @@ int main(int argc, char **argv) ERR(!digest_algo, "EVP_get_digestbyname"); =20 #ifndef USE_PKCS7 + + unsigned int flags =3D + CMS_NOCERTS | + CMS_PARTIAL | + CMS_BINARY | + CMS_DETACHED | + CMS_STREAM | + CMS_NOSMIMECAP | + CMS_NO_SIGNING_TIME | + use_keyid; + + if ((EVP_PKEY_is_a(private_key, "ML-DSA-44") || + EVP_PKEY_is_a(private_key, "ML-DSA-65") || + EVP_PKEY_is_a(private_key, "ML-DSA-87")) && + OPENSSL_VERSION_MAJOR < 4) { + /* ML-DSA + CMS_NOATTR is not supported in openssl-3.5 + * and before. + */ + use_signed_attrs =3D 0; + } + + flags |=3D use_signed_attrs; + /* Load the signature message from the digest buffer. */ - cms =3D CMS_sign(NULL, NULL, NULL, NULL, - CMS_NOCERTS | CMS_PARTIAL | CMS_BINARY | - CMS_DETACHED | CMS_STREAM); + cms =3D CMS_sign(NULL, NULL, NULL, NULL, flags); ERR(!cms, "CMS_sign"); =20 - ERR(!CMS_add1_signer(cms, x509, private_key, digest_algo, - CMS_NOCERTS | CMS_BINARY | - CMS_NOSMIMECAP | use_keyid | - use_signed_attrs), + ERR(!CMS_add1_signer(cms, x509, private_key, digest_algo, flags), "CMS_add1_signer"); - ERR(CMS_final(cms, bm, NULL, CMS_NOCERTS | CMS_BINARY) !=3D 1, + ERR(CMS_final(cms, bm, NULL, flags) !=3D 1, "CMS_final"); =20 #else