From patchwork Tue Mar 29 03:26:55 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Fu Wei Fu X-Patchwork-Id: 64554 Delivered-To: patch@linaro.org Received: by 10.112.199.169 with SMTP id jl9csp1774445lbc; Mon, 28 Mar 2016 20:28:46 -0700 (PDT) X-Received: by 10.140.100.244 with SMTP id s107mr38457185qge.19.1459222126037; Mon, 28 Mar 2016 20:28:46 -0700 (PDT) Return-Path: Received: from lists.xenproject.org (lists.xenproject.org. [192.237.175.120]) by mx.google.com with ESMTPS id z69si23918207qgd.9.2016.03.28.20.28.45 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 28 Mar 2016 20:28:46 -0700 (PDT) Received-SPF: neutral (google.com: 192.237.175.120 is neither permitted nor denied by best guess record for domain of xen-devel-bounces@lists.xen.org) client-ip=192.237.175.120; Authentication-Results: mx.google.com; spf=neutral (google.com: 192.237.175.120 is neither permitted nor denied by best guess record for domain of xen-devel-bounces@lists.xen.org) smtp.mailfrom=xen-devel-bounces@lists.xen.org Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.84_2) (envelope-from ) id 1akkJJ-0005wA-Jf; Tue, 29 Mar 2016 03:27:17 +0000 Received: from mail6.bemta6.messagelabs.com ([85.158.143.247]) by lists.xenproject.org with esmtp (Exim 4.84_2) (envelope-from ) id 1akkJI-0005w4-Lk for xen-devel@lists.xensource.com; Tue, 29 Mar 2016 03:27:16 +0000 Received: from [85.158.143.35] by server-1.bemta-6.messagelabs.com id BD/2B-29237-316F9F65; Tue, 29 Mar 2016 03:27:15 +0000 X-Env-Sender: fu.wei@linaro.org X-Msg-Ref: server-13.tower-21.messagelabs.com!1459222033!6378773!1 X-Originating-IP: [209.132.183.28] X-SpamReason: No, hits=0.0 required=7.0 tests=sa_preprocessor: VHJ1c3RlZCBJUDogMjA5LjEzMi4xODMuMjggPT4gNTQwNjQ=\n X-StarScan-Received: X-StarScan-Version: 8.11; banners=-,-,- X-VirusChecked: Checked Received: (qmail 15760 invoked from network); 29 Mar 2016 03:27:15 -0000 Received: from mx1.redhat.com (HELO mx1.redhat.com) (209.132.183.28) by server-13.tower-21.messagelabs.com with DHE-RSA-AES256-GCM-SHA384 encrypted SMTP; 29 Mar 2016 03:27:15 -0000 Received: from int-mx14.intmail.prod.int.phx2.redhat.com (int-mx14.intmail.prod.int.phx2.redhat.com [10.5.11.27]) by mx1.redhat.com (Postfix) with ESMTPS id 4C2D083F44; Tue, 29 Mar 2016 03:27:13 +0000 (UTC) Received: from magi-f22.redhat.com (vpn1-7-88.pek2.redhat.com [10.72.7.88]) by int-mx14.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id u2T3R8IP022289; Mon, 28 Mar 2016 23:27:09 -0400 From: fu.wei@linaro.org To: xen-devel@lists.xensource.com, julien.grall@arm.com, stefano.stabellini@citrix.com, dgdegra@tycho.nsa.gov, konrad.wilk@oracle.com Date: Tue, 29 Mar 2016 11:26:55 +0800 Message-Id: <1459222015-12036-1-git-send-email-fu.wei@linaro.org> X-Scanned-By: MIMEDefang 2.68 on 10.5.11.27 Cc: jcm@redhat.com, Fu Wei , leif.lindholm@linaro.org, linaro-uefi@lists.linaro.org Subject: [Xen-devel] [PATCH v3] xen/arm64: check XSM Magic and Signature from the second unknown module. X-BeenThere: xen-devel@lists.xen.org X-Mailman-Version: 2.1.18 Precedence: list List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Errors-To: xen-devel-bounces@lists.xen.org Sender: "Xen-devel" From: Fu Wei This patch add a check_xsm_signature static function for detecting XSM from the second unknown module. If Xen can't get the kind of module from compatible, we guess the kind of these first two unknown respectively: (1) The first unknown must be kernel; (2) The second unknown is ramdisk, only if we have ramdisk; (3) Start from the 2nd unknown, detect the XSM binary signature; (4) If we got XSM in the 2nd unknown, that means we don't load initrd. Signed-off-by: Fu Wei --- Changelog: v3: Using memcmp instead of strncmp. Using "return 0;" instead of panic(); Improve some comments. v2: http://lists.xen.org/archives/html/xen-devel/2016-03/msg03543.html Using XEN_MAGIC macro instead of 0xf97cff8c : uint32_t selinux_magic = 0xf97cff8c; --> uint32_t xen_magic = XEN_MAGIC; Comment out the code(return 0 directly), if CONFIG_FLASK is not set. v1: http://lists.xen.org/archives/html/xen-devel/2016-03/msg02430.html The first upstream patch to xen-devel mailing lists. xen/arch/arm/bootfdt.c | 54 +++++++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 53 insertions(+), 1 deletion(-) diff --git a/xen/arch/arm/bootfdt.c b/xen/arch/arm/bootfdt.c index 8a14015..10d3382 100644 --- a/xen/arch/arm/bootfdt.c +++ b/xen/arch/arm/bootfdt.c @@ -163,6 +163,49 @@ static void __init process_memory_node(const void *fdt, int node, } } +/** + * check_xsm_signature - Check XSM Magic and Signature of the module header + * A XSM module has a special header + * ------------------------------------------------ + * uint magic | uint target_len | uchar target[8] | + * 0xf97cff8c | 8 | "XenFlask" | + * ------------------------------------------------ + * 0xf97cff8c is policy magic number (XSM_MAGIC). + * So we only read the first 16 bytes of the module, then check these three + * parts. This checking (memcmp) assumes little-endian byte order. + */ +static bool __init check_xsm_signature(const void *fdt, int node, + const char *name, + u32 address_cells, u32 size_cells) +{ +#ifdef CONFIG_FLASK + u32 xen_magic = XSM_MAGIC, target_len = 8; + const struct fdt_property *prop; + unsigned char buff[16]; + paddr_t start, size; + const __be32 *cell; + int len; + + prop = fdt_get_property(fdt, node, "reg", &len); + if ( !prop || len < dt_cells_to_size(address_cells + size_cells)) + return 0; + + cell = (const __be32 *)prop->data; + device_tree_get_reg(&cell, address_cells, size_cells, &start, &size); + + copy_from_paddr(buff, start, sizeof(buff)); + + if (memcmp(buff, (void *) &xen_magic, sizeof(u32)) || + memcmp(buff + sizeof(u32), (void *) &target_len, sizeof(u32)) || + memcmp(buff + sizeof(u32) * 2, "XenFlask", target_len)) + return 0; + + return 1; +#else + return 0; +#endif +} + static void __init process_multiboot_node(const void *fdt, int node, const char *name, u32 address_cells, u32 size_cells) @@ -186,7 +229,13 @@ static void __init process_multiboot_node(const void *fdt, int node, else kind = BOOTMOD_UNKNOWN; - /* Guess that first two unknown are kernel and ramdisk respectively. */ + /** + * Guess the kind of these first two unknown respectively: + * (1) The first unknown must be kernel; + * (2) The second unknown is ramdisk, only if we have ramdisk; + * (3) Start from the 2nd unknown, detect the XSM binary signature; + * (4) If we got XSM in the 2nd unknown, that means we have not initrd. + */ if ( kind == BOOTMOD_UNKNOWN ) { switch ( kind_guess++ ) @@ -195,6 +244,9 @@ static void __init process_multiboot_node(const void *fdt, int node, case 1: kind = BOOTMOD_RAMDISK; break; default: break; } + if (kind_guess > 1 && check_xsm_signature(fdt, node, name, + address_cells, size_cells)) + kind = BOOTMOD_XSM; } prop = fdt_get_property(fdt, node, "reg", &len);