From mboxrd@z Thu Jan 1 00:00:00 1970 Delivery-date: Tue, 30 Jul 2024 10:36:00 +0200 Received: from metis.whiteo.stw.pengutronix.de ([2a0a:edc0:2:b01:1d::104]) by lore.white.stw.pengutronix.de with esmtps (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.96) (envelope-from ) id 1sYiKu-004PGx-1T for lore@lore.pengutronix.de; Tue, 30 Jul 2024 10:36:00 +0200 Received: from bombadil.infradead.org ([2607:7c80:54:3::133]) by metis.whiteo.stw.pengutronix.de with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1sYiKt-0007Ne-NY for lore@pengutronix.de; Tue, 30 Jul 2024 10:36:00 +0200 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:Cc:List-Subscribe: List-Help:List-Post:List-Archive:List-Unsubscribe:List-Id: Content-Transfer-Encoding:Content-Type:In-Reply-To:From:References:To:Subject :MIME-Version:Date:Message-ID:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=5ZSpd25swx96JFbH/c2tbFEEqu/nAQZMBMVVb16yFnM=; b=itlWfKX9H8effg SIvr2dDPL4YEvaVfy9BSt20UfGq4yszg1/ZmrI20pLqy/ad01pWBtFim9TM8X53EEp3tyR1QjlnJc F9CjAHu5MY41Vnteu7KsM4b/4yPNVRLE7Nn8qcNHObKohgbFZDYxCmyg3KSbxsQSVHvSwxGD558MD iTdqT1z5S/RDXul9IDW2w+VBNw1qWH6ShXuPOAhkQ4jXOMP2VtCowEdc0PdrFPUvVFMbbLv+v7QEl PlYQxLFtwxMWYawW2L5Jh9auZu56ifPz2VLUvmVKwGw9BuJcM43UAzraO8hYr41ylHt3TeXonwXig qk9kqPfukrfz3PdgguFQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1sYiKM-0000000EJ0g-2nc7; Tue, 30 Jul 2024 08:35:26 +0000 Received: from metis.whiteo.stw.pengutronix.de ([2a0a:edc0:2:b01:1d::104]) by bombadil.infradead.org with esmtps (Exim 4.97.1 #2 (Red Hat Linux)) id 1sYiD0-0000000EFW5-32zs for barebox@lists.infradead.org; Tue, 30 Jul 2024 08:27:52 +0000 Received: from ptz.office.stw.pengutronix.de ([2a0a:edc0:0:900:1d::77] helo=[127.0.0.1]) by metis.whiteo.stw.pengutronix.de with esmtp (Exim 4.92) (envelope-from ) id 1sYiCz-000621-BK; Tue, 30 Jul 2024 10:27:49 +0200 Message-ID: Date: Tue, 30 Jul 2024 10:27:47 +0200 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird To: Marco Felsch References: <20240703-v2024-05-0-topic-hab-v2-0-17419aa5d3a3@pengutronix.de> <20240703-v2024-05-0-topic-hab-v2-7-17419aa5d3a3@pengutronix.de> <38177bf4-4a0e-4765-881e-8404370bfdd5@pengutronix.de> <20240704081526.ksuml42balhx4jym@pengutronix.de> Content-Language: en-US, de-DE, de-BE From: Ahmad Fatoum In-Reply-To: <20240704081526.ksuml42balhx4jym@pengutronix.de> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240730_012750_811710_DD0B9E68 X-CRM114-Status: GOOD ( 24.46 ) X-BeenThere: barebox@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: BAREBOX Sender: "barebox" X-SA-Exim-Connect-IP: 2607:7c80:54:3::133 X-SA-Exim-Mail-From: barebox-bounces+lore=pengutronix.de@lists.infradead.org X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on metis.whiteo.stw.pengutronix.de X-Spam-Level: X-Spam-Status: No, score=-5.3 required=4.0 tests=AWL,BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,RCVD_IN_DNSWL_MED,SPF_HELO_NONE,SPF_NONE autolearn=unavailable autolearn_force=no version=3.4.2 Subject: Re: [PATCH v2 7/9] i.MX8M: HABv4: add an option to allow key revocation X-SA-Exim-Version: 4.2.1 (built Wed, 08 May 2019 21:11:16 +0000) X-SA-Exim-Scanned: Yes (on metis.whiteo.stw.pengutronix.de) Hello Marco, On 7/4/24 10:15, Marco Felsch wrote: > Hi Ahmad, > > On 24-07-03, Ahmad Fatoum wrote: >> Hello Marco, >> >> On 03.07.24 19:20, Marco Felsch wrote: >>> The HAB code needs an special [Unlock] instruction to keep the >>> SRK_REVOKE fuse bank unlocked. This is required if a key needs to be >>> revoked. >>> >>> Signed-off-by: Marco Felsch >>> --- >>> arch/arm/mach-imx/Kconfig | 8 ++++++++ >>> include/mach/imx/habv4-imx8-gencsf.h | 6 ++++++ >>> 2 files changed, 14 insertions(+) >>> >>> diff --git a/arch/arm/mach-imx/Kconfig b/arch/arm/mach-imx/Kconfig >>> index 61258137736f..68f55971506b 100644 >>> --- a/arch/arm/mach-imx/Kconfig >>> +++ b/arch/arm/mach-imx/Kconfig >>> @@ -835,6 +835,14 @@ config HABV4_QSPI >>> help >>> Enable this option to build signed QSPI/FlexSPI images. >>> >>> +config HABV4_CSF_UNLOCK_SRK_REVOKE >>> + depends on HABV4 >>> + bool "Unlock SRK revocation" >>> + help >>> + Enable this option to instruct the HAB code to not lock >>> + the SRK_REVOKE_LOCK sticky bit. This is required for key >>> + revocation. Don't enable this if you are unsure. >> >> I think for added safety we should have an extra option that prompts >> for the key to be revoked and an initcall that is activated depending >> on it, e.g.: >> >> config HABV4_CSF_SRK_REVOKE_INDEX >> int "SRK to revoke" >> range 0 3 >> default 0 >> depends on HABV4_CSF_SRK_REVOKE_UNLOCK >> help >> Which of the first three SRKs to revoke. The SRK indices are >> 1-based. Saying 0 here will just print the SRK Revocation >> register without modification. SRK #4 is immutable. >> >> Proceed with caution, revoking a SRK is irreversible and >> manual manipulation of this code can brick the board! >> >> if HABV4_CSF_SRK_REVOKE_INDEX = HABV4_SRK_INDEX >> comment "Can't revoke same SRK used for signing" >> comment "Attempts to build a signed barebox image will fail" >> endif >> >> and then some code that checks the same above condition during final >> assembly of the signed image. >> >> What do you think? > > That's an good idea to make it more user-friendly for most users :) > Regarding this patchset I do see it more as an addition since for my > project the revocation is checked on every startup and we do allow the > revocation of multiple SRK slots at the same time. Ok. I just have a single nit then, can you rename HABV4_CSF_UNLOCK_SRK_REVOKE to HABV4_CSF_SRK_REVOKE_UNLOCK, so we can add HABV4_CSF_SRK_REVOKE_INDEX in future with the same prefix? Thanks, Ahmad > > Regards, > Marco > >>> config HAB_CERTS_ENV >>> depends on HAB >>> bool "Specify certificates in environment" >>> diff --git a/include/mach/imx/habv4-imx8-gencsf.h b/include/mach/imx/habv4-imx8-gencsf.h >>> index 5f92ceceab00..56d9ef2de92f 100644 >>> --- a/include/mach/imx/habv4-imx8-gencsf.h >>> +++ b/include/mach/imx/habv4-imx8-gencsf.h >>> @@ -36,6 +36,12 @@ hab [Unlock] >>> hab Engine = CAAM >>> hab Features = RNG, MID >>> >>> +#if defined(CONFIG_HABV4_CSF_UNLOCK_SRK_REVOKE) >>> +hab [Unlock] >>> +hab Engine = OCOTP >>> +hab Features = SRK REVOKE >>> +#endif >>> + >>> hab [Install Key] >>> /* verification key index in key store (0, 2...4) */ >>> hab Verification index = 0 >>> >> >> -- >> Pengutronix e.K. | | >> Steuerwalder Str. 21 | http://www.pengutronix.de/ | >> 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 | >> Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 | >> >> >