From mboxrd@z Thu Jan 1 00:00:00 1970 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 1D05026157C for ; Tue, 11 Mar 2025 16:59:14 +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=1741712358; cv=none; b=A7mxGVD5yTGXeEYgnMpNIlhbH7gm8UHrV6FHTMkTVc9hqy6ho1jxCD7+KQTd4hx71yzLkTDnqUNNbVyMF4L73Pr/jrcljVokNrsc01vl2cba2Y6u0Q3r61XksQPSPouCMWXBVPL1kaH2X+j0hB2UZlTaAqkAObX8wrA8lNnrbvw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1741712358; c=relaxed/simple; bh=Kxrawuzb4BFgf9aq26SAU4jjKNmS3pqCwyCxaidubj0=; h=From:To:Cc:Subject:In-Reply-To:References:Date:Message-ID: MIME-Version:Content-Type; b=b8yqqYqGTNNaP/kgemnXbfaFr1ucEkp5dSn9uvzv3kr3jaAUxaHDv2HLcc/vU4ztNhtYBjQQEhI9b9EizvmGloSt5t3hWlCXom71KQUNK84riP/F2xyIBusatyj2zMb+Y+Ag1SpjOCjlvpkXZYOUozB9S8pWEaz+gFmh6iF6KgU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none 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=dhBQMdF9; arc=none smtp.client-ip=170.10.133.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none 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="dhBQMdF9" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1741712353; 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=0BPrX/3i7B8WQ59BDJo83O4/lZ+88fFfKiRl6URWuaA=; b=dhBQMdF9QNcOnCtXgIHQO7/8d+SvOBpJF7i7d85YnO9V/xlaXXYwhqhLR5Vwa6DrVAjTW8 HhxO2qH/sFRzvrRImZT9jxSF7XetfAq0YyZqOMfDR1LnJW/aP7rc/Bk/DlAmxRWagaYoJj ZbxkoqS9ByKafS+60bXj+m/qPupXrLw= Received: from mail-wr1-f69.google.com (mail-wr1-f69.google.com [209.85.221.69]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-44-f4pu3KGrMOu_oNkqg7CTgg-1; Tue, 11 Mar 2025 12:59:12 -0400 X-MC-Unique: f4pu3KGrMOu_oNkqg7CTgg-1 X-Mimecast-MFC-AGG-ID: f4pu3KGrMOu_oNkqg7CTgg_1741712351 Received: by mail-wr1-f69.google.com with SMTP id ffacd0b85a97d-3933ab5b1d5so564134f8f.2 for ; Tue, 11 Mar 2025 09:59:11 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1741712351; x=1742317151; h=mime-version:message-id:date:references:in-reply-to:subject:cc:to :from:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=0BPrX/3i7B8WQ59BDJo83O4/lZ+88fFfKiRl6URWuaA=; b=sG836BBKdxkbXSc6Pv5SWHzCABeTZJdI5HUIjSldZ1mBz98bQRt9qSmWiS+z2YxU/+ hyba+C7PGvfz3iCix8SvTZywJswGA0cM6XLDjjg7djQKWFJ76TDMawsKtrisVglCdnGB oIOQ3GH8bI2T/6UaoRiK7n7GflDZ5uTdNIwe0n8erVYA8YZBh1GQVCVUe9QDGOmHyG/8 6+1PuoN1LDpcx9h3Z2UH4tnUp6sjX+4R6EHOur1ikwOBa+uIr1IONOxaAnAIHEh7pZRi rbzGUz6swsm0d+3q+g+0w//7M4VarYr/Yf89gHoJyduUVdLkZaOQZRI1s3l8w5R1hYPl nBeA== X-Forwarded-Encrypted: i=1; AJvYcCU6S1n2IUx42AMycixfDpiuVfETG9wdsWMdKH8HdQrCIG6jRasB/XxH6u2+ONwkDbwqA3y+vqd/gsYeVuM=@vger.kernel.org X-Gm-Message-State: AOJu0YzeueShvYoEk8DpK/RQsEJ+NWw/saukUhSTaW0tV67EKJdSPT68 Sl3s2yh140AhuQAmv6aL9XuwB6s7+zbWSj0kVb+wo8mQ9V7vlCgyYClMEjA2ajoi38fgvCMMhxR mzS9Ldm7GyU50DM88pr8hq+d/dv+5XnpN65Rnx7Cw5Vo+ZYNqkftRb5rRGKu/Bg== X-Gm-Gg: ASbGncsWa4esf8dfZTeSIfYg/i80YTqAIyPShBbkYuRB2X/0UNLWtgyY2xahuwl205w tsh4CfSi5siGpry0ftopiyp5sGZZNXOqzMuZVL9sLEGJPZmUMtAyF3Q3vzqPq/3SEqNLYZj1xd1 Fc6dBbHn6g+qmCLvSoXeclaA9No8MNpVczBC1pwxfzRcKw42fF6rht5DwuU1TlRSh59fvD50pjp lvmgD7cMWgAbt5v6wBi0Kx7dds6Q5XyA/JE3/SVcKLoZYYH54ncrQus+tTZLyGO+D4KgJimzGFA CzT/3Vt9ZLU= X-Received: by 2002:a5d:64c3:0:b0:391:2932:e67b with SMTP id ffacd0b85a97d-39132dacfdbmr18967111f8f.35.1741712350841; Tue, 11 Mar 2025 09:59:10 -0700 (PDT) X-Google-Smtp-Source: AGHT+IFthIkbIza4asy8rbMgye5BDrJXoQTmIsJn6D/IMOoIcmgMxFtoxcwjFBwF1vhjSSm/3R/XiQ== X-Received: by 2002:a5d:64c3:0:b0:391:2932:e67b with SMTP id ffacd0b85a97d-39132dacfdbmr18967090f8f.35.1741712350383; Tue, 11 Mar 2025 09:59:10 -0700 (PDT) Received: from fedora (g3.ign.cz. [91.219.240.17]) by smtp.gmail.com with ESMTPSA id ffacd0b85a97d-3912c101febsm18182505f8f.81.2025.03.11.09.59.09 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 11 Mar 2025 09:59:09 -0700 (PDT) From: Vitaly Kuznetsov To: Ard Biesheuvel , linux-kernel@vger.kernel.org Cc: x86@kernel.org, Ard Biesheuvel , "H. Peter Anvin" , Gerd Hoffmann , Juergen Gross , Jan Beulich , Paul Durrant , David Woodhouse Subject: Re: [RFC PATCH resend] x86/boot: Drop CRC-32 checksum and the build tool that generates it In-Reply-To: <20250307164801.885261-2-ardb+git@google.com> References: <20250307164801.885261-2-ardb+git@google.com> Date: Tue, 11 Mar 2025 17:59:08 +0100 Message-ID: <87bju7o65f.fsf@redhat.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain Ard Biesheuvel writes: > From: Ard Biesheuvel > > Apart from some sanity checks on the size of setup.bin, the only > remaining task carried out by the arch/x86/boot/tools/build.c build tool > is generating the CRC-32 checksum of the bzImage. This feature was added > in commit > > 7d6e737c8d2698b6 ("x86: add a crc32 checksum to the kernel image.") > > without any motivation (or any commit log text, for that matter). Doing some history digging, it seems this was done for Xen: https://lore.kernel.org/lkml/1202936100-30859-1-git-send-email-ijc@hellion.org.uk/T/#m263fdcf0ff3f31ca8e5cd619aa81c7735fa8be91 Let me Cc: a few Xen folks for visibility. > This > checksum is not verified by any known bootloader, and given that > > a) the checksum of the entire bzImage is reported by most tools (zlib, > rhash) as 0xffffffff and not 0x0 as documented, > b) the checksum is corrupted when the image is signed for secure boot, > which means that no distro ships x86 images with valid CRCs, Note that at least Fedora/RHEL/... distros ship keyless HMAC hash alongside vmlinuz binary, e.g. on my Fedora40: $ cat /boot/.vmlinuz-6.12.6-100.fc40.x86_64.hmac 19aec080fbd05c5de42db486653a5d9e9d69b59ac8d216ea89850ccf1f538c08ff4ada450989ddf1be81e23fd3c99253939d0a2153d3fd270cc1ed561c04294e vmlinuz-6.12.6-100.fc40.x86_64 and this is created _after_ SB signing. AFAIU, the need for this is coming from FIPS requirements; this makes me wornder if the CRC-32 is an early implementation of the same thing. > > it seems quite unlikely that this checksum is being used, so let's just > drop it, along with the tool that generates it. > > Instead, use simple file concatenation and truncation to combine the two > pieces into bzImage, and replace the checks on the size of the setup > block with a couple of ASSERT()s in the linker script. > > Cc: "H. Peter Anvin" > Cc: Gerd Hoffmann > Cc: Vitaly Kuznetsov > Signed-off-by: Ard Biesheuvel > --- > Documentation/arch/x86/boot.rst | 10 - > arch/x86/boot/Makefile | 7 +- > arch/x86/boot/compressed/vmlinux.lds.S | 3 +- > arch/x86/boot/setup.ld | 2 + > arch/x86/boot/tools/.gitignore | 2 - > arch/x86/boot/tools/build.c | 247 -------------------- > 6 files changed, 5 insertions(+), 266 deletions(-) > > diff --git a/Documentation/arch/x86/boot.rst b/Documentation/arch/x86/boot.rst > index 76f53d3450e7..77e6163288db 100644 > --- a/Documentation/arch/x86/boot.rst > +++ b/Documentation/arch/x86/boot.rst > @@ -1038,16 +1038,6 @@ Offset/size: 0x000c/4 > This field contains maximal allowed type for setup_data and setup_indirect structs. > > > -The Image Checksum > -================== > - > -From boot protocol version 2.08 onwards the CRC-32 is calculated over > -the entire file using the characteristic polynomial 0x04C11DB7 and an > -initial remainder of 0xffffffff. The checksum is appended to the > -file; therefore the CRC of the file up to the limit specified in the > -syssize field of the header is always 0. > - > - > The Kernel Command Line > ======================= > > diff --git a/arch/x86/boot/Makefile b/arch/x86/boot/Makefile > index 9cc0ff6e9067..8589471b65a1 100644 > --- a/arch/x86/boot/Makefile > +++ b/arch/x86/boot/Makefile > @@ -35,7 +35,6 @@ setup-y += video-vesa.o > setup-y += video-bios.o > > targets += $(setup-y) > -hostprogs := tools/build > hostprogs += mkcpustr > > HOST_EXTRACFLAGS += -I$(srctree)/tools/include \ > @@ -61,11 +60,9 @@ KBUILD_CFLAGS += $(CONFIG_CC_IMPLICIT_FALLTHROUGH) > $(obj)/bzImage: asflags-y := $(SVGA_MODE) > > quiet_cmd_image = BUILD $@ > -silent_redirect_image = >/dev/null > -cmd_image = $(obj)/tools/build $(obj)/setup.bin $(obj)/vmlinux.bin \ > - $(obj)/zoffset.h $@ $($(quiet)redirect_image) > + cmd_image = cp $< $@; truncate -s %4K $@; cat $(obj)/vmlinux.bin >>$@ > > -$(obj)/bzImage: $(obj)/setup.bin $(obj)/vmlinux.bin $(obj)/tools/build FORCE > +$(obj)/bzImage: $(obj)/setup.bin $(obj)/vmlinux.bin FORCE > $(call if_changed,image) > @$(kecho) 'Kernel: $@ is ready' ' (#'$(or $(KBUILD_BUILD_VERSION),`cat .version`)')' > > diff --git a/arch/x86/boot/compressed/vmlinux.lds.S b/arch/x86/boot/compressed/vmlinux.lds.S > index 083ec6d7722a..48d0b5184557 100644 > --- a/arch/x86/boot/compressed/vmlinux.lds.S > +++ b/arch/x86/boot/compressed/vmlinux.lds.S > @@ -48,8 +48,7 @@ SECTIONS > *(.data) > *(.data.*) > > - /* Add 4 bytes of extra space for a CRC-32 checksum */ > - . = ALIGN(. + 4, 0x200); > + . = ALIGN(0x200); > _edata = . ; > } > . = ALIGN(L1_CACHE_BYTES); > diff --git a/arch/x86/boot/setup.ld b/arch/x86/boot/setup.ld > index 3a2d1360abb0..e1d594a60204 100644 > --- a/arch/x86/boot/setup.ld > +++ b/arch/x86/boot/setup.ld > @@ -45,6 +45,8 @@ SECTIONS > > setup_size = ALIGN(ABSOLUTE(.), 4096); > setup_sects = ABSOLUTE(setup_size / 512); > + ASSERT(setup_sects >= 5, "The setup must be at least 5 sectors in size"); > + ASSERT(setup_sects <= 64, "The setup must be at most 64 sectors in size"); > } > > . = ALIGN(16); > diff --git a/arch/x86/boot/tools/.gitignore b/arch/x86/boot/tools/.gitignore > deleted file mode 100644 > index ae91f4d0d78b..000000000000 > --- a/arch/x86/boot/tools/.gitignore > +++ /dev/null > @@ -1,2 +0,0 @@ > -# SPDX-License-Identifier: GPL-2.0-only > -build > diff --git a/arch/x86/boot/tools/build.c b/arch/x86/boot/tools/build.c > deleted file mode 100644 > index 10311d77c67f..000000000000 > --- a/arch/x86/boot/tools/build.c > +++ /dev/null > @@ -1,247 +0,0 @@ > -// SPDX-License-Identifier: GPL-2.0 > -/* > - * Copyright (C) 1991, 1992 Linus Torvalds > - * Copyright (C) 1997 Martin Mares > - * Copyright (C) 2007 H. Peter Anvin > - */ > - > -/* > - * This file builds a disk-image from three different files: > - * > - * - setup: 8086 machine code, sets up system parm > - * - system: 80386 code for actual system > - * - zoffset.h: header with ZO_* defines > - * > - * It does some checking that all files are of the correct type, and writes > - * the result to the specified destination, removing headers and padding to > - * the right amount. It also writes some system data to stdout. > - */ > - > -/* > - * Changes by tytso to allow root device specification > - * High loaded stuff by Hans Lermen & Werner Almesberger, Feb. 1996 > - * Cross compiling fixes by Gertjan van Wingerde, July 1996 > - * Rewritten by Martin Mares, April 1997 > - * Substantially overhauled by H. Peter Anvin, April 2007 > - */ > - > -#include > -#include > -#include > -#include > -#include > -#include > -#include > -#include > -#include > -#include > - > -typedef unsigned char u8; > -typedef unsigned short u16; > -typedef unsigned int u32; > - > -/* Minimal number of setup sectors */ > -#define SETUP_SECT_MIN 5 > -#define SETUP_SECT_MAX 64 > - > -/* This must be large enough to hold the entire setup */ > -u8 buf[SETUP_SECT_MAX*512]; > - > -static unsigned long _edata; > - > -/*----------------------------------------------------------------------*/ > - > -static const u32 crctab32[] = { > - 0x00000000, 0x77073096, 0xee0e612c, 0x990951ba, 0x076dc419, > - 0x706af48f, 0xe963a535, 0x9e6495a3, 0x0edb8832, 0x79dcb8a4, > - 0xe0d5e91e, 0x97d2d988, 0x09b64c2b, 0x7eb17cbd, 0xe7b82d07, > - 0x90bf1d91, 0x1db71064, 0x6ab020f2, 0xf3b97148, 0x84be41de, > - 0x1adad47d, 0x6ddde4eb, 0xf4d4b551, 0x83d385c7, 0x136c9856, > - 0x646ba8c0, 0xfd62f97a, 0x8a65c9ec, 0x14015c4f, 0x63066cd9, > - 0xfa0f3d63, 0x8d080df5, 0x3b6e20c8, 0x4c69105e, 0xd56041e4, > - 0xa2677172, 0x3c03e4d1, 0x4b04d447, 0xd20d85fd, 0xa50ab56b, > - 0x35b5a8fa, 0x42b2986c, 0xdbbbc9d6, 0xacbcf940, 0x32d86ce3, > - 0x45df5c75, 0xdcd60dcf, 0xabd13d59, 0x26d930ac, 0x51de003a, > - 0xc8d75180, 0xbfd06116, 0x21b4f4b5, 0x56b3c423, 0xcfba9599, > - 0xb8bda50f, 0x2802b89e, 0x5f058808, 0xc60cd9b2, 0xb10be924, > - 0x2f6f7c87, 0x58684c11, 0xc1611dab, 0xb6662d3d, 0x76dc4190, > - 0x01db7106, 0x98d220bc, 0xefd5102a, 0x71b18589, 0x06b6b51f, > - 0x9fbfe4a5, 0xe8b8d433, 0x7807c9a2, 0x0f00f934, 0x9609a88e, > - 0xe10e9818, 0x7f6a0dbb, 0x086d3d2d, 0x91646c97, 0xe6635c01, > - 0x6b6b51f4, 0x1c6c6162, 0x856530d8, 0xf262004e, 0x6c0695ed, > - 0x1b01a57b, 0x8208f4c1, 0xf50fc457, 0x65b0d9c6, 0x12b7e950, > - 0x8bbeb8ea, 0xfcb9887c, 0x62dd1ddf, 0x15da2d49, 0x8cd37cf3, > - 0xfbd44c65, 0x4db26158, 0x3ab551ce, 0xa3bc0074, 0xd4bb30e2, > - 0x4adfa541, 0x3dd895d7, 0xa4d1c46d, 0xd3d6f4fb, 0x4369e96a, > - 0x346ed9fc, 0xad678846, 0xda60b8d0, 0x44042d73, 0x33031de5, > - 0xaa0a4c5f, 0xdd0d7cc9, 0x5005713c, 0x270241aa, 0xbe0b1010, > - 0xc90c2086, 0x5768b525, 0x206f85b3, 0xb966d409, 0xce61e49f, > - 0x5edef90e, 0x29d9c998, 0xb0d09822, 0xc7d7a8b4, 0x59b33d17, > - 0x2eb40d81, 0xb7bd5c3b, 0xc0ba6cad, 0xedb88320, 0x9abfb3b6, > - 0x03b6e20c, 0x74b1d29a, 0xead54739, 0x9dd277af, 0x04db2615, > - 0x73dc1683, 0xe3630b12, 0x94643b84, 0x0d6d6a3e, 0x7a6a5aa8, > - 0xe40ecf0b, 0x9309ff9d, 0x0a00ae27, 0x7d079eb1, 0xf00f9344, > - 0x8708a3d2, 0x1e01f268, 0x6906c2fe, 0xf762575d, 0x806567cb, > - 0x196c3671, 0x6e6b06e7, 0xfed41b76, 0x89d32be0, 0x10da7a5a, > - 0x67dd4acc, 0xf9b9df6f, 0x8ebeeff9, 0x17b7be43, 0x60b08ed5, > - 0xd6d6a3e8, 0xa1d1937e, 0x38d8c2c4, 0x4fdff252, 0xd1bb67f1, > - 0xa6bc5767, 0x3fb506dd, 0x48b2364b, 0xd80d2bda, 0xaf0a1b4c, > - 0x36034af6, 0x41047a60, 0xdf60efc3, 0xa867df55, 0x316e8eef, > - 0x4669be79, 0xcb61b38c, 0xbc66831a, 0x256fd2a0, 0x5268e236, > - 0xcc0c7795, 0xbb0b4703, 0x220216b9, 0x5505262f, 0xc5ba3bbe, > - 0xb2bd0b28, 0x2bb45a92, 0x5cb36a04, 0xc2d7ffa7, 0xb5d0cf31, > - 0x2cd99e8b, 0x5bdeae1d, 0x9b64c2b0, 0xec63f226, 0x756aa39c, > - 0x026d930a, 0x9c0906a9, 0xeb0e363f, 0x72076785, 0x05005713, > - 0x95bf4a82, 0xe2b87a14, 0x7bb12bae, 0x0cb61b38, 0x92d28e9b, > - 0xe5d5be0d, 0x7cdcefb7, 0x0bdbdf21, 0x86d3d2d4, 0xf1d4e242, > - 0x68ddb3f8, 0x1fda836e, 0x81be16cd, 0xf6b9265b, 0x6fb077e1, > - 0x18b74777, 0x88085ae6, 0xff0f6a70, 0x66063bca, 0x11010b5c, > - 0x8f659eff, 0xf862ae69, 0x616bffd3, 0x166ccf45, 0xa00ae278, > - 0xd70dd2ee, 0x4e048354, 0x3903b3c2, 0xa7672661, 0xd06016f7, > - 0x4969474d, 0x3e6e77db, 0xaed16a4a, 0xd9d65adc, 0x40df0b66, > - 0x37d83bf0, 0xa9bcae53, 0xdebb9ec5, 0x47b2cf7f, 0x30b5ffe9, > - 0xbdbdf21c, 0xcabac28a, 0x53b39330, 0x24b4a3a6, 0xbad03605, > - 0xcdd70693, 0x54de5729, 0x23d967bf, 0xb3667a2e, 0xc4614ab8, > - 0x5d681b02, 0x2a6f2b94, 0xb40bbe37, 0xc30c8ea1, 0x5a05df1b, > - 0x2d02ef8d > -}; > - > -static u32 partial_crc32_one(u8 c, u32 crc) > -{ > - return crctab32[(crc ^ c) & 0xff] ^ (crc >> 8); > -} > - > -static u32 partial_crc32(const u8 *s, int len, u32 crc) > -{ > - while (len--) > - crc = partial_crc32_one(*s++, crc); > - return crc; > -} > - > -static void die(const char * str, ...) > -{ > - va_list args; > - va_start(args, str); > - vfprintf(stderr, str, args); > - va_end(args); > - fputc('\n', stderr); > - exit(1); > -} > - > -static void usage(void) > -{ > - die("Usage: build setup system zoffset.h image"); > -} > - > -/* > - * Parse zoffset.h and find the entry points. We could just #include zoffset.h > - * but that would mean tools/build would have to be rebuilt every time. It's > - * not as if parsing it is hard... > - */ > -#define PARSE_ZOFS(p, sym) do { \ > - if (!strncmp(p, "#define ZO_" #sym " ", 11+sizeof(#sym))) \ > - sym = strtoul(p + 11 + sizeof(#sym), NULL, 16); \ > -} while (0) > - > -static void parse_zoffset(char *fname) > -{ > - FILE *file; > - char *p; > - int c; > - > - file = fopen(fname, "r"); > - if (!file) > - die("Unable to open `%s': %m", fname); > - c = fread(buf, 1, sizeof(buf) - 1, file); > - if (ferror(file)) > - die("read-error on `zoffset.h'"); > - fclose(file); > - buf[c] = 0; > - > - p = (char *)buf; > - > - while (p && *p) { > - PARSE_ZOFS(p, _edata); > - > - p = strchr(p, '\n'); > - while (p && (*p == '\r' || *p == '\n')) > - p++; > - } > -} > - > -int main(int argc, char ** argv) > -{ > - unsigned int i, sz, setup_sectors; > - int c; > - struct stat sb; > - FILE *file, *dest; > - int fd; > - void *kernel; > - u32 crc = 0xffffffffUL; > - > - if (argc != 5) > - usage(); > - parse_zoffset(argv[3]); > - > - dest = fopen(argv[4], "w"); > - if (!dest) > - die("Unable to write `%s': %m", argv[4]); > - > - /* Copy the setup code */ > - file = fopen(argv[1], "r"); > - if (!file) > - die("Unable to open `%s': %m", argv[1]); > - c = fread(buf, 1, sizeof(buf), file); > - if (ferror(file)) > - die("read-error on `setup'"); > - if (c < 1024) > - die("The setup must be at least 1024 bytes"); > - if (get_unaligned_le16(&buf[510]) != 0xAA55) > - die("Boot block hasn't got boot flag (0xAA55)"); > - fclose(file); > - > - /* Pad unused space with zeros */ > - setup_sectors = (c + 4095) / 4096; > - setup_sectors *= 8; > - if (setup_sectors < SETUP_SECT_MIN) > - setup_sectors = SETUP_SECT_MIN; > - i = setup_sectors*512; > - memset(buf+c, 0, i-c); > - > - /* Open and stat the kernel file */ > - fd = open(argv[2], O_RDONLY); > - if (fd < 0) > - die("Unable to open `%s': %m", argv[2]); > - if (fstat(fd, &sb)) > - die("Unable to stat `%s': %m", argv[2]); > - if (_edata != sb.st_size) > - die("Unexpected file size `%s': %u != %u", argv[2], _edata, > - sb.st_size); > - sz = _edata - 4; > - kernel = mmap(NULL, sz, PROT_READ, MAP_SHARED, fd, 0); > - if (kernel == MAP_FAILED) > - die("Unable to mmap '%s': %m", argv[2]); > - > - crc = partial_crc32(buf, i, crc); > - if (fwrite(buf, 1, i, dest) != i) > - die("Writing setup failed"); > - > - /* Copy the kernel code */ > - crc = partial_crc32(kernel, sz, crc); > - if (fwrite(kernel, 1, sz, dest) != sz) > - die("Writing kernel failed"); > - > - /* Write the CRC */ > - put_unaligned_le32(crc, buf); > - if (fwrite(buf, 1, 4, dest) != 4) > - die("Writing CRC failed"); > - > - /* Catch any delayed write failures */ > - if (fclose(dest)) > - die("Writing image failed"); > - > - close(fd); > - > - /* Everything is OK */ > - return 0; > -} -- Vitaly