From mboxrd@z Thu Jan 1 00:00:00 1970 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 D4DFFC433FE for ; Thu, 12 May 2022 17:19:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1356946AbiELRT0 (ORCPT ); Thu, 12 May 2022 13:19:26 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33300 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1356938AbiELRTT (ORCPT ); Thu, 12 May 2022 13:19:19 -0400 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 0827E26AD8B for ; Thu, 12 May 2022 10:19:17 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1652375956; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=oEFXUtbClHFFmeWShgFw8vJilTye35f28JoIGyS8/V0=; b=PW/pWgpLsParDTloa5Bo+H5FCUyjPR68E4gX13hTVgMxEYzFq7TyyIhDMywem0yMjwMPh+ ixw5+MX2yr4Ctbz2Y4WE1rNa6ZqiAhU12r2N0uBg2TYTDAWJOFpEPWnyY/ohqNRhoqki43 BsC7PZvcjyWtZwWNrQatAMjZ2Whs7bY= Received: from mail-qv1-f69.google.com (mail-qv1-f69.google.com [209.85.219.69]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-651-ynpo4T01NVigB8skKL85Lw-1; Thu, 12 May 2022 13:19:15 -0400 X-MC-Unique: ynpo4T01NVigB8skKL85Lw-1 Received: by mail-qv1-f69.google.com with SMTP id bu6-20020ad455e6000000b004563a74e3f9so5008959qvb.9 for ; Thu, 12 May 2022 10:19:15 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=oEFXUtbClHFFmeWShgFw8vJilTye35f28JoIGyS8/V0=; b=HByzc2BqVbJ5Rk/wX/o1e8NEyyB0/+CTRWeibR47IteszpWOS4+MWPDjINzX7+Ezig iuOelxM5a4yAcYtNQzEbYYFsfgI9Yg0zbVRxSL/WVqO2qmtFS9wFnK1fv9q+L50uLWpL U/wqG44dHzSPWV8PfEyiTsM0sS8KuMsY1Dasg/ZBnESIrxE43UERplkHoTcWCu6b8FwF sWXB8EiDjEDuLfeW6P8uzBkKnEycVelI0xIPLzawUSI5He58TBpTMpFm/B7gZ4WTb47W tWfS5qU/TYh1EncJ7p0j9+JvVcUxIhpvMVB1IValIIYHBmw/o1LyuTLIIgEDHh73lean B+Ag== X-Gm-Message-State: AOAM532EzueP39PkU7PK6pam+rkqkKBjlZNqKm+pGj0/ApZ6b7uhGzVT IR1bL6+qSBgxKKEiCgPTuxhzYUVMpg30FK3yY4HI4kbht9E0cPlBsZeiLgOgJVRCIeeUlQ8G1uo 0FC+2ct4gYHyQtwOEwDAy X-Received: by 2002:a05:620a:c43:b0:67d:f048:f5e9 with SMTP id u3-20020a05620a0c4300b0067df048f5e9mr707660qki.281.1652375954897; Thu, 12 May 2022 10:19:14 -0700 (PDT) X-Google-Smtp-Source: ABdhPJykQ0VJO8iqsfXZLVTIsX7tPq3/5ge1HQXrF4uHNL4asswoVlbtihDk13sRBvxtNiaNVD0epg== X-Received: by 2002:a05:620a:c43:b0:67d:f048:f5e9 with SMTP id u3-20020a05620a0c4300b0067df048f5e9mr707646qki.281.1652375954576; Thu, 12 May 2022 10:19:14 -0700 (PDT) Received: from localhost ([66.187.232.66]) by smtp.gmail.com with ESMTPSA id j126-20020a375584000000b006a103949657sm27998qkb.38.2022.05.12.10.19.13 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 12 May 2022 10:19:13 -0700 (PDT) Date: Thu, 12 May 2022 13:19:12 -0400 From: Mike Snitzer To: Matthias Kaehlcke Cc: Alasdair Kergon , Mike Snitzer , Kees Cook , James Morris , "Serge E . Hallyn" , dm-devel@redhat.com, linux-kernel@vger.kernel.org, linux-raid@vger.kernel.org, Song Liu , Douglas Anderson , linux-security-module@vger.kernel.org Subject: Re: [PATCH v3 1/3] dm: Add verity helpers for LoadPin Message-ID: References: <20220504195419.1143099-1-mka@chromium.org> <20220504125404.v3.1.I3e928575a23481121e73286874c4c2bdb403355d@changeid> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-raid@vger.kernel.org On Wed, May 11 2022 at 4:54P -0400, Matthias Kaehlcke wrote: > Alasdar/Mike, I'd be interested in your take on adding these functions > to verity/DM, to get an idea whether this series has a path forward to > landing upstream. I'll be reviewing your patchset now. Comments inlined below. > On Wed, May 04, 2022 at 12:54:17PM -0700, Matthias Kaehlcke wrote: > > LoadPin limits loading of kernel modules, firmware and certain > > other files to a 'pinned' file system (typically a read-only > > rootfs). To provide more flexibility LoadPin is being extended > > to also allow loading these files from trusted dm-verity > > devices. For that purpose LoadPin can be provided with a list > > of verity root digests that it should consider as trusted. > > > > Add a bunch of helpers to allow LoadPin to check whether a DM > > device is a trusted verity device. The new functions broadly > > fall in two categories: those that need access to verity > > internals (like the root digest), and the 'glue' between > > LoadPin and verity. The new file dm-verity-loadpin.c contains > > the glue functions. > > > > Signed-off-by: Matthias Kaehlcke > > --- > > > > Changes in v3: > > - none > > > > Changes in v2: > > - none > > > > drivers/md/Makefile | 6 +++ > > drivers/md/dm-verity-loadpin.c | 80 +++++++++++++++++++++++++++++++ > > drivers/md/dm-verity-target.c | 33 +++++++++++++ > > drivers/md/dm-verity.h | 4 ++ > > include/linux/dm-verity-loadpin.h | 27 +++++++++++ > > 5 files changed, 150 insertions(+) > > create mode 100644 drivers/md/dm-verity-loadpin.c > > create mode 100644 include/linux/dm-verity-loadpin.h > > > > diff --git a/drivers/md/Makefile b/drivers/md/Makefile > > index 0454b0885b01..e12cd004d375 100644 > > --- a/drivers/md/Makefile > > +++ b/drivers/md/Makefile > > @@ -100,6 +100,12 @@ ifeq ($(CONFIG_IMA),y) > > dm-mod-objs += dm-ima.o > > endif > > > > +ifeq ($(CONFIG_DM_VERITY),y) > > +ifeq ($(CONFIG_SECURITY_LOADPIN),y) > > +dm-mod-objs += dm-verity-loadpin.o > > +endif > > +endif > > + Why are you extending dm-mod-objs? Why not dm-verity-objs? > > ifeq ($(CONFIG_DM_VERITY_FEC),y) > > dm-verity-objs += dm-verity-fec.o > > endif > > diff --git a/drivers/md/dm-verity-loadpin.c b/drivers/md/dm-verity-loadpin.c > > new file mode 100644 > > index 000000000000..972ca93a2231 > > --- /dev/null > > +++ b/drivers/md/dm-verity-loadpin.c > > @@ -0,0 +1,80 @@ > > +// SPDX-License-Identifier: GPL-2.0-only > > + > > +#include > > +#include > > +#include > > + > > +#include "dm.h" > > +#include "dm-verity.h" > > + > > +static struct list_head *trusted_root_digests; > > + > > +/* > > + * Sets the root digests of verity devices which LoadPin considers as trusted. > > + * > > + * This function must only be called once. > > + */ > > +void dm_verity_loadpin_set_trusted_root_digests(struct list_head *digests) > > +{ > > + if (!trusted_root_digests) > > + trusted_root_digests = digests; > > + else > > + pr_warn("verity root digests trusted by LoadPin are already set!!!\n"); > > +} Would prefer you set a DM_MSG_PREFIX and use DMWARN() instead. You never explicitly initialize trusted_root_digests to NULL. Also, I'll have to look at the caller(s), but without locking this branching is racey. > > + > > +static bool is_trusted_verity_target(struct dm_target *ti) > > +{ > > + u8 *root_digest; > > + unsigned int digest_size; > > + struct trusted_root_digest *trd; > > + bool trusted = false; > > + > > + if (!dm_is_verity_target(ti)) > > + return false; > > + > > + if (dm_verity_get_root_digest(ti, &root_digest, &digest_size)) > > + return false; > > + > > + list_for_each_entry(trd, trusted_root_digests, node) { > > + if ((trd->len == digest_size) && > > + !memcmp(trd->data, root_digest, digest_size)) { > > + trusted = true; > > + break; > > + } > > + } > > + > > + kfree(root_digest); > > + > > + return trusted; > > +} > > + > > +/* > > + * Determines whether a mapped device is a verity device that is trusted > > + * by LoadPin. > > + */ > > +bool dm_verity_loadpin_is_md_trusted(struct mapped_device *md) > > +{ > > + int srcu_idx; > > + struct dm_table *table; > > + unsigned int num_targets; > > + bool trusted = false; > > + int i; > > + > > + if (!trusted_root_digests || list_empty(trusted_root_digests)) > > + return false; Again, where is the locking to protect trusted_root_digests? > > + table = dm_get_live_table(md, &srcu_idx); > > + num_targets = dm_table_get_num_targets(table); > > + for (i = 0; i < num_targets; i++) { > > + struct dm_target *ti = dm_table_get_target(table, i); > > + > > + if (is_trusted_verity_target(ti)) { > > + trusted = true; > > + break; > > + } > > + } > > + > > + dm_put_live_table(md, srcu_idx); > > + > > + return trusted; > > +} > > diff --git a/drivers/md/dm-verity-target.c b/drivers/md/dm-verity-target.c > > index 80133aae0db3..6f07b849fcb2 100644 > > --- a/drivers/md/dm-verity-target.c > > +++ b/drivers/md/dm-verity-target.c > > @@ -19,6 +19,7 @@ > > #include > > #include > > #include > > +#include > > > > #define DM_MSG_PREFIX "verity" > > > > @@ -1310,6 +1311,38 @@ static int verity_ctr(struct dm_target *ti, unsigned argc, char **argv) > > return r; > > } > > > > +/* > > + * Check whether a DM target is a verity target. > > + */ > > +bool dm_is_verity_target(struct dm_target *ti) > > +{ > > + return ti->type->module == THIS_MODULE; > > +} > > +EXPORT_SYMBOL_GPL(dm_is_verity_target); > > + > > +/* > > + * Get the root digest of a verity target. > > + * > > + * Returns a copy of the root digest, the caller is responsible for > > + * freeing the memory of the digest. > > + */ > > +int dm_verity_get_root_digest(struct dm_target *ti, u8 **root_digest, unsigned int *digest_size) > > +{ > > + struct dm_verity *v = ti->private; > > + > > + if (!dm_is_verity_target(ti)) > > + return -EINVAL; > > + > > + *root_digest = kmemdup(v->root_digest, v->digest_size, GFP_KERNEL); > > + if (*root_digest == NULL) > > + return -ENOMEM; > > + > > + *digest_size = v->digest_size; > > + > > + return 0; > > +} > > +EXPORT_SYMBOL_GPL(dm_verity_get_root_digest); > > + > > static struct target_type verity_target = { > > .name = "verity", > > .version = {1, 8, 0}, > > diff --git a/drivers/md/dm-verity.h b/drivers/md/dm-verity.h > > index 4e769d13473a..c832cc3e3d24 100644 > > --- a/drivers/md/dm-verity.h > > +++ b/drivers/md/dm-verity.h > > @@ -129,4 +129,8 @@ extern int verity_hash(struct dm_verity *v, struct ahash_request *req, > > extern int verity_hash_for_block(struct dm_verity *v, struct dm_verity_io *io, > > sector_t block, u8 *digest, bool *is_zero); > > > > +extern bool dm_is_verity_target(struct dm_target *ti); > > +extern int dm_verity_get_root_digest(struct dm_target *ti, u8 **root_digest, > > + unsigned int *digest_size); > > + > > #endif /* DM_VERITY_H */ > > diff --git a/include/linux/dm-verity-loadpin.h b/include/linux/dm-verity-loadpin.h > > new file mode 100644 > > index 000000000000..12a86911d05a > > --- /dev/null > > +++ b/include/linux/dm-verity-loadpin.h > > @@ -0,0 +1,27 @@ > > +/* SPDX-License-Identifier: GPL-2.0 */ > > + > > +#ifndef __LINUX_DM_VERITY_LOADPIN_H > > +#define __LINUX_DM_VERITY_LOADPIN_H > > + > > +#include > > + > > +struct mapped_device; > > + > > +struct trusted_root_digest { > > + u8 *data; > > + unsigned int len; > > + struct list_head node; > > +}; > > + > > +#if IS_ENABLED(CONFIG_SECURITY_LOADPIN) && IS_BUILTIN(CONFIG_DM_VERITY) > > +void dm_verity_loadpin_set_trusted_root_digests(struct list_head *digests); > > +bool dm_verity_loadpin_is_md_trusted(struct mapped_device *md); > > +#else > > +static inline void dm_verity_loadpin_set_trusted_root_digests(struct list_head *digests) {} > > +static inline bool dm_verity_loadpin_is_md_trusted(struct mapped_device *md) > > +{ > > + return false; > > +} > > +#endif > > + > > +#endif /* __LINUX_DM_LOADPIN_H */ > > -- > > 2.36.0.464.gb9c8b46e94-goog > > > From mboxrd@z Thu Jan 1 00:00:00 1970 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 us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id DBAC0C433EF for ; Thu, 12 May 2022 17:19:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1652375964; h=from:from:sender:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:list-id:list-help: list-unsubscribe:list-subscribe:list-post; bh=/tUHZxa7VdcG+cKBPsnOIU0h/w3eWl/5MoxGH/eS8TQ=; 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Thu, 12 May 2022 10:19:14 -0700 (PDT) X-Google-Smtp-Source: ABdhPJykQ0VJO8iqsfXZLVTIsX7tPq3/5ge1HQXrF4uHNL4asswoVlbtihDk13sRBvxtNiaNVD0epg== X-Received: by 2002:a05:620a:c43:b0:67d:f048:f5e9 with SMTP id u3-20020a05620a0c4300b0067df048f5e9mr707646qki.281.1652375954576; Thu, 12 May 2022 10:19:14 -0700 (PDT) Received: from localhost ([66.187.232.66]) by smtp.gmail.com with ESMTPSA id j126-20020a375584000000b006a103949657sm27998qkb.38.2022.05.12.10.19.13 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 12 May 2022 10:19:13 -0700 (PDT) Date: Thu, 12 May 2022 13:19:12 -0400 From: Mike Snitzer To: Matthias Kaehlcke Message-ID: References: <20220504195419.1143099-1-mka@chromium.org> <20220504125404.v3.1.I3e928575a23481121e73286874c4c2bdb403355d@changeid> MIME-Version: 1.0 In-Reply-To: X-Scanned-By: MIMEDefang 2.84 on 10.11.54.1 Subject: Re: [dm-devel] [PATCH v3 1/3] dm: Add verity helpers for LoadPin X-BeenThere: dm-devel@redhat.com X-Mailman-Version: 2.1.29 Precedence: list List-Id: device-mapper development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-security-module@vger.kernel.org, Douglas Anderson , Kees Cook , Mike Snitzer , James Morris , linux-kernel@vger.kernel.org, linux-raid@vger.kernel.org, Song Liu , dm-devel@redhat.com, Alasdair Kergon , "Serge E . Hallyn" Errors-To: dm-devel-bounces@redhat.com Sender: "dm-devel" X-Scanned-By: MIMEDefang 2.78 on 10.11.54.4 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=dm-devel-bounces@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Disposition: inline Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit On Wed, May 11 2022 at 4:54P -0400, Matthias Kaehlcke wrote: > Alasdar/Mike, I'd be interested in your take on adding these functions > to verity/DM, to get an idea whether this series has a path forward to > landing upstream. I'll be reviewing your patchset now. Comments inlined below. > On Wed, May 04, 2022 at 12:54:17PM -0700, Matthias Kaehlcke wrote: > > LoadPin limits loading of kernel modules, firmware and certain > > other files to a 'pinned' file system (typically a read-only > > rootfs). To provide more flexibility LoadPin is being extended > > to also allow loading these files from trusted dm-verity > > devices. For that purpose LoadPin can be provided with a list > > of verity root digests that it should consider as trusted. > > > > Add a bunch of helpers to allow LoadPin to check whether a DM > > device is a trusted verity device. The new functions broadly > > fall in two categories: those that need access to verity > > internals (like the root digest), and the 'glue' between > > LoadPin and verity. The new file dm-verity-loadpin.c contains > > the glue functions. > > > > Signed-off-by: Matthias Kaehlcke > > --- > > > > Changes in v3: > > - none > > > > Changes in v2: > > - none > > > > drivers/md/Makefile | 6 +++ > > drivers/md/dm-verity-loadpin.c | 80 +++++++++++++++++++++++++++++++ > > drivers/md/dm-verity-target.c | 33 +++++++++++++ > > drivers/md/dm-verity.h | 4 ++ > > include/linux/dm-verity-loadpin.h | 27 +++++++++++ > > 5 files changed, 150 insertions(+) > > create mode 100644 drivers/md/dm-verity-loadpin.c > > create mode 100644 include/linux/dm-verity-loadpin.h > > > > diff --git a/drivers/md/Makefile b/drivers/md/Makefile > > index 0454b0885b01..e12cd004d375 100644 > > --- a/drivers/md/Makefile > > +++ b/drivers/md/Makefile > > @@ -100,6 +100,12 @@ ifeq ($(CONFIG_IMA),y) > > dm-mod-objs += dm-ima.o > > endif > > > > +ifeq ($(CONFIG_DM_VERITY),y) > > +ifeq ($(CONFIG_SECURITY_LOADPIN),y) > > +dm-mod-objs += dm-verity-loadpin.o > > +endif > > +endif > > + Why are you extending dm-mod-objs? Why not dm-verity-objs? > > ifeq ($(CONFIG_DM_VERITY_FEC),y) > > dm-verity-objs += dm-verity-fec.o > > endif > > diff --git a/drivers/md/dm-verity-loadpin.c b/drivers/md/dm-verity-loadpin.c > > new file mode 100644 > > index 000000000000..972ca93a2231 > > --- /dev/null > > +++ b/drivers/md/dm-verity-loadpin.c > > @@ -0,0 +1,80 @@ > > +// SPDX-License-Identifier: GPL-2.0-only > > + > > +#include > > +#include > > +#include > > + > > +#include "dm.h" > > +#include "dm-verity.h" > > + > > +static struct list_head *trusted_root_digests; > > + > > +/* > > + * Sets the root digests of verity devices which LoadPin considers as trusted. > > + * > > + * This function must only be called once. > > + */ > > +void dm_verity_loadpin_set_trusted_root_digests(struct list_head *digests) > > +{ > > + if (!trusted_root_digests) > > + trusted_root_digests = digests; > > + else > > + pr_warn("verity root digests trusted by LoadPin are already set!!!\n"); > > +} Would prefer you set a DM_MSG_PREFIX and use DMWARN() instead. You never explicitly initialize trusted_root_digests to NULL. Also, I'll have to look at the caller(s), but without locking this branching is racey. > > + > > +static bool is_trusted_verity_target(struct dm_target *ti) > > +{ > > + u8 *root_digest; > > + unsigned int digest_size; > > + struct trusted_root_digest *trd; > > + bool trusted = false; > > + > > + if (!dm_is_verity_target(ti)) > > + return false; > > + > > + if (dm_verity_get_root_digest(ti, &root_digest, &digest_size)) > > + return false; > > + > > + list_for_each_entry(trd, trusted_root_digests, node) { > > + if ((trd->len == digest_size) && > > + !memcmp(trd->data, root_digest, digest_size)) { > > + trusted = true; > > + break; > > + } > > + } > > + > > + kfree(root_digest); > > + > > + return trusted; > > +} > > + > > +/* > > + * Determines whether a mapped device is a verity device that is trusted > > + * by LoadPin. > > + */ > > +bool dm_verity_loadpin_is_md_trusted(struct mapped_device *md) > > +{ > > + int srcu_idx; > > + struct dm_table *table; > > + unsigned int num_targets; > > + bool trusted = false; > > + int i; > > + > > + if (!trusted_root_digests || list_empty(trusted_root_digests)) > > + return false; Again, where is the locking to protect trusted_root_digests? > > + table = dm_get_live_table(md, &srcu_idx); > > + num_targets = dm_table_get_num_targets(table); > > + for (i = 0; i < num_targets; i++) { > > + struct dm_target *ti = dm_table_get_target(table, i); > > + > > + if (is_trusted_verity_target(ti)) { > > + trusted = true; > > + break; > > + } > > + } > > + > > + dm_put_live_table(md, srcu_idx); > > + > > + return trusted; > > +} > > diff --git a/drivers/md/dm-verity-target.c b/drivers/md/dm-verity-target.c > > index 80133aae0db3..6f07b849fcb2 100644 > > --- a/drivers/md/dm-verity-target.c > > +++ b/drivers/md/dm-verity-target.c > > @@ -19,6 +19,7 @@ > > #include > > #include > > #include > > +#include > > > > #define DM_MSG_PREFIX "verity" > > > > @@ -1310,6 +1311,38 @@ static int verity_ctr(struct dm_target *ti, unsigned argc, char **argv) > > return r; > > } > > > > +/* > > + * Check whether a DM target is a verity target. > > + */ > > +bool dm_is_verity_target(struct dm_target *ti) > > +{ > > + return ti->type->module == THIS_MODULE; > > +} > > +EXPORT_SYMBOL_GPL(dm_is_verity_target); > > + > > +/* > > + * Get the root digest of a verity target. > > + * > > + * Returns a copy of the root digest, the caller is responsible for > > + * freeing the memory of the digest. > > + */ > > +int dm_verity_get_root_digest(struct dm_target *ti, u8 **root_digest, unsigned int *digest_size) > > +{ > > + struct dm_verity *v = ti->private; > > + > > + if (!dm_is_verity_target(ti)) > > + return -EINVAL; > > + > > + *root_digest = kmemdup(v->root_digest, v->digest_size, GFP_KERNEL); > > + if (*root_digest == NULL) > > + return -ENOMEM; > > + > > + *digest_size = v->digest_size; > > + > > + return 0; > > +} > > +EXPORT_SYMBOL_GPL(dm_verity_get_root_digest); > > + > > static struct target_type verity_target = { > > .name = "verity", > > .version = {1, 8, 0}, > > diff --git a/drivers/md/dm-verity.h b/drivers/md/dm-verity.h > > index 4e769d13473a..c832cc3e3d24 100644 > > --- a/drivers/md/dm-verity.h > > +++ b/drivers/md/dm-verity.h > > @@ -129,4 +129,8 @@ extern int verity_hash(struct dm_verity *v, struct ahash_request *req, > > extern int verity_hash_for_block(struct dm_verity *v, struct dm_verity_io *io, > > sector_t block, u8 *digest, bool *is_zero); > > > > +extern bool dm_is_verity_target(struct dm_target *ti); > > +extern int dm_verity_get_root_digest(struct dm_target *ti, u8 **root_digest, > > + unsigned int *digest_size); > > + > > #endif /* DM_VERITY_H */ > > diff --git a/include/linux/dm-verity-loadpin.h b/include/linux/dm-verity-loadpin.h > > new file mode 100644 > > index 000000000000..12a86911d05a > > --- /dev/null > > +++ b/include/linux/dm-verity-loadpin.h > > @@ -0,0 +1,27 @@ > > +/* SPDX-License-Identifier: GPL-2.0 */ > > + > > +#ifndef __LINUX_DM_VERITY_LOADPIN_H > > +#define __LINUX_DM_VERITY_LOADPIN_H > > + > > +#include > > + > > +struct mapped_device; > > + > > +struct trusted_root_digest { > > + u8 *data; > > + unsigned int len; > > + struct list_head node; > > +}; > > + > > +#if IS_ENABLED(CONFIG_SECURITY_LOADPIN) && IS_BUILTIN(CONFIG_DM_VERITY) > > +void dm_verity_loadpin_set_trusted_root_digests(struct list_head *digests); > > +bool dm_verity_loadpin_is_md_trusted(struct mapped_device *md); > > +#else > > +static inline void dm_verity_loadpin_set_trusted_root_digests(struct list_head *digests) {} > > +static inline bool dm_verity_loadpin_is_md_trusted(struct mapped_device *md) > > +{ > > + return false; > > +} > > +#endif > > + > > +#endif /* __LINUX_DM_LOADPIN_H */ > > -- > > 2.36.0.464.gb9c8b46e94-goog > > > -- dm-devel mailing list dm-devel@redhat.com https://listman.redhat.com/mailman/listinfo/dm-devel