From mboxrd@z Thu Jan 1 00:00:00 1970 Delivery-date: Tue, 16 Aug 2022 10:44:04 +0200 Received: from metis.ext.pengutronix.de ([2001:67c:670:201:290:27ff:fe1d:cc33]) by lore.white.stw.pengutronix.de with esmtps (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.94.2) (envelope-from ) id 1oNsBB-000UbA-Bh for lore@lore.pengutronix.de; Tue, 16 Aug 2022 10:44:04 +0200 Received: from bombadil.infradead.org ([2607:7c80:54:3::133]) by metis.ext.pengutronix.de with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1oNsB9-00042m-DC for lore@pengutronix.de; Tue, 16 Aug 2022 10:44:04 +0200 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:From:In-Reply-To: Content-Type:MIME-Version:References:Message-ID:Subject:Cc:To:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=OZ7aNyZLQPXKk2SLL38oiEPyWcfJedb1NHzWVOotF14=; b=wD2iK43ZEBxoJ1F0xfWZnqwTBl jjBKG9aN19RDHqauQbRUrvVSYhbc/8lZRKbb7uN6asF+nT8GlTyXmv6dq40sn1qKS6MSu5HMtHr3l Of3e/0yS8CTp3SFrKIXADSC5o+nRb/NZe351r43nL5vONOkfQ11NzCCIBg8Xrr1qzprPm+VZ1ogXB ET5TOzlyeoVCYD6heTLNgVqeBoHcOEvyTIn/pJAIvyDvnPJdo6Uy5gQ1FqCRz7bqlpFXj2a2otGGO yJrntgNIeNbkPZjrhxzGyUUuEVHMSL5Q4r3XjnnyFJOPBYADAJjBDTQyM+4GvDsu4glUB1THvv1Ns 9POI9Xew==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1oNs9Z-00GukP-QJ; Tue, 16 Aug 2022 08:42:25 +0000 Received: from metis.ext.pengutronix.de ([2001:67c:670:201:290:27ff:fe1d:cc33]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1oNs9V-00Guiy-Cs for barebox@lists.infradead.org; Tue, 16 Aug 2022 08:42:22 +0000 Received: from ptx.hi.pengutronix.de ([2001:67c:670:100:1d::c0]) by metis.ext.pengutronix.de with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1oNs9T-0003nj-72; Tue, 16 Aug 2022 10:42:19 +0200 Received: from sha by ptx.hi.pengutronix.de with local (Exim 4.92) (envelope-from ) id 1oNs9S-0007Hu-UA; Tue, 16 Aug 2022 10:42:18 +0200 Date: Tue, 16 Aug 2022 10:42:18 +0200 To: Ahmad Fatoum Cc: barebox@lists.infradead.org Message-ID: <20220816084218.GK17485@pengutronix.de> References: <20220815130955.2332697-1-a.fatoum@pengutronix.de> <20220815130955.2332697-3-a.fatoum@pengutronix.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20220815130955.2332697-3-a.fatoum@pengutronix.de> X-Sent-From: Pengutronix Hildesheim X-URL: http://www.pengutronix.de/ X-Accept-Language: de,en X-Accept-Content-Type: text/plain User-Agent: Mutt/1.10.1 (2018-07-13) From: Sascha Hauer X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20220816_014221_458063_C866B412 X-CRM114-Status: GOOD ( 23.42 ) 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: , 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.ext.pengutronix.de X-Spam-Level: X-Spam-Status: No, score=-3.8 required=4.0 tests=AWL,BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,RCVD_IN_DNSWL_LOW,SPF_HELO_NONE,SPF_NONE, T_SCC_BODY_TEXT_LINE,URIBL_BLOCKED autolearn=unavailable autolearn_force=no version=3.4.2 Subject: Re: [PATCH 3/3] firmware: add external firmware PBL support X-SA-Exim-Version: 4.2.1 (built Wed, 08 May 2019 21:11:16 +0000) X-SA-Exim-Scanned: Yes (on metis.ext.pengutronix.de) On Mon, Aug 15, 2022 at 03:09:55PM +0200, Ahmad Fatoum wrote: > Normally, barebox embds firmware into the binary referencing it, which > means that device tree blobs, RAM training code and e.g. TF-A for i.MX8M > end up in the prebootloader, while, e.g. Freescale FMan microcode ends > up in barebox proper. The only exception so far was barebox proper: > When only the PBL fits in on-chip SRAM, barebox proper is chainloaded > from the boot medium. To avoid TOCTOU attack, it's read fully into DRAM > after setup and then a SHA256 is calculated and compared against the > hash embedded in barebox PBL, which in a secure boot system would be > trusted by virtue of the PBL as a whole being verified beforehand by > the BootROM. > > Reuse this mechanism to support arbitrary firmware, which is now termed > external firmware. Such firmware is placed beyond the piggydata (barebox > proper) and only offset and hash are included in the prebootloader > image. The new get_builtin_firmware_ext() is used to retrieve this > external firmware after integrity verification with SHA256. Does it make sense to use this mechanism for barebox proper as well? > #define get_builtin_firmware(name, start, size) \ > { \ > extern char _fw_##name##_start[]; \ > @@ -65,4 +78,22 @@ void firmwaremgr_list_handlers(void); > *size = _fw_##name##_end - _fw_##name##_start; \ > } > > +#define get_builtin_firmware_ext(name, base, start, size) \ base is unused. It would be nice if users could use the same macro for both internal and external firmware, but I have no idea how and if this could be implemented. Sascha -- 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 |