src/cros-vbutil.c

   1 /*
   2  * cros-vbutil - Tool for signing kernels using the Chromium OS verified boot
   3  * format, using widely-shared "developer" keys. The output of this tool is
   4  * intended to be written to a GPT partition of type "Chrome OS Kernel", such
   5  * that a Chromium OS bootloader can find it.
   6  *
   7  * Much of this is adapted from Google's vboot_reference project found here:
   8  *   https://chromium.googlesource.com/chromiumos/platform/vboot_reference
   9  *
  10  * Copyright (c) 2010 The Chromium OS Authors. All rights reserved.
  11  *
  12  * Redistribution and use in source and binary forms, with or without
  13  * modification, are permitted provided that the following conditions are
  14  * met:
  15  *
  16  *    * Redistributions of source code must retain the above copyright
  17  * notice, this list of conditions and the following disclaimer.
  18  *    * Redistributions in binary form must reproduce the above
  19  * copyright notice, this list of conditions and the following disclaimer
  20  * in the documentation and/or other materials provided with the
  21  * distribution.
  22  *    * Neither the name of Google Inc. nor the names of its
  23  * contributors may be used to endorse or promote products derived from
  24  * this software without specific prior written permission.
  25  *
  26  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  27  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  28  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  29  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  30  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  31  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  32  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  33  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  34  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  35  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  36  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  37  *
  38  * Rewritten:
  39  * Copyright (c) 2021 Brian Norris <computersforpeace@gmail.com>
  40  *
  41  * This program is free software; you can redistribute it and/or modify it
  42  * under the terms of the GNU General Public License version 2 as published
  43  * by the Free Software Foundation.
  44  */
  45
  46 #include <fcntl.h>
  47 #include <stdio.h>
  48 #include <string.h>
  49 #include <sys/stat.h>
  50 #include <unistd.h>
  51
  52 #include <openssl/rsa.h>
  53 #include <openssl/x509.h>
  54 #include <openssl/sha.h>
  55
  56 #define BLOCK_PAD 65536
  57 /* Sections are aligned to 4K blocks */
  58 #define ALIGN 4096
  59 #define ROUNDUP(x) (((x) + (ALIGN-1)) & ~(ALIGN-1))
  60
  61 /*
  62  * Signature size, in bytes. This is an RSA-2048 encryption of a SHA256 hash.
  63  */
  64 #define SIG_SIZE (2048 / 8)
  65
  66 /*
  67  * From vboot_reference: tests/devkeys/kernel.keyblock
  68  */
  69 static const unsigned char keyblock[] = {
  70         0x43, 0x48, 0x52, 0x4f, 0x4d, 0x45, 0x4f, 0x53, 0x02, 0x00, 0x00, 0x00,
  71         0x01, 0x00, 0x00, 0x00, 0xb8, 0x04, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  72         0xa0, 0x02, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x02, 0x00, 0x00,
  73         0x00, 0x00, 0x00, 0x00, 0x78, 0x02, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  74         0x48, 0x02, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x40, 0x00, 0x00, 0x00,
  75         0x00, 0x00, 0x00, 0x00, 0x78, 0x02, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  76         0x07, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x20, 0x00, 0x00, 0x00,
  77         0x00, 0x00, 0x00, 0x00, 0x08, 0x02, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  78         0x04, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0x00, 0x00, 0x00,
  79         0x00, 0x00, 0x00, 0x00, 0x40, 0x00, 0x00, 0x00, 0xcb, 0x02, 0x40, 0x41,
  80         0x1d, 0x2d, 0x86, 0x0f, 0x6d, 0x53, 0xcc, 0xcc, 0xa7, 0x9b, 0x1b, 0xca,
  81         0xdc, 0x22, 0xc4, 0xc2, 0x3a, 0x72, 0xa5, 0x12, 0x21, 0xfe, 0x78, 0x1d,
  82         0x9c, 0x03, 0x65, 0x0c, 0x94, 0xba, 0x3d, 0x5b, 0x5e, 0x98, 0x16, 0x8a,
  83         0xaf, 0xaf, 0x67, 0x5a, 0x46, 0x88, 0x2c, 0xf0, 0x2a, 0x65, 0xbd, 0xc7,
  84         0x59, 0xcc, 0x70, 0xe9, 0x01, 0x4e, 0x7d, 0x8c, 0x43, 0x2e, 0x1c, 0x6d,
  85         0x72, 0x15, 0xaf, 0xd0, 0x71, 0x9f, 0xb4, 0x3a, 0xe7, 0x44, 0x82, 0xd1,
  86         0x83, 0x8b, 0x9d, 0x6c, 0x64, 0x99, 0xaf, 0xdb, 0x8a, 0xcc, 0xd1, 0xd6,
  87         0x83, 0xa6, 0xa4, 0xea, 0xa9, 0x81, 0x1d, 0x9f, 0x1b, 0x5a, 0x8c, 0xf8,
  88         0xdb, 0x26, 0x21, 0xb2, 0x7b, 0x53, 0x92, 0xf0, 0x6a, 0xc5, 0x8c, 0x11,
  89         0xba, 0x7e, 0x43, 0xcb, 0x1e, 0x57, 0xa1, 0x6e, 0xd5, 0xfe, 0x82, 0x28,
  90         0x3d, 0x6d, 0xbd, 0x97, 0xb0, 0xe8, 0xfb, 0x1f, 0x88, 0x06, 0x1b, 0x0a,
  91         0xc5, 0x8f, 0x96, 0x69, 0x48, 0x69, 0x41, 0x2a, 0x52, 0xd7, 0xb7, 0x33,
  92         0x78, 0x8b, 0x6f, 0x97, 0xa7, 0x7d, 0xdc, 0xd0, 0x2b, 0xd9, 0x81, 0x67,
  93         0xc9, 0x3f, 0xa9, 0xb4, 0x1e, 0x0b, 0x08, 0x54, 0xc6, 0x01, 0xc6, 0x20,
  94         0xe6, 0xc6, 0x09, 0x5f, 0x0a, 0xc5, 0x02, 0x05, 0x6b, 0x40, 0x96, 0x11,
  95         0x20, 0xe5, 0xa2, 0x88, 0x37, 0x6a, 0xd3, 0xda, 0xda, 0xda, 0x76, 0x1c,
  96         0xe4, 0x3d, 0x2c, 0xfe, 0x65, 0x86, 0x98, 0xa2, 0xa8, 0x49, 0x7d, 0x26,
  97         0x45, 0x14, 0x04, 0x10, 0xe3, 0x38, 0x4b, 0x66, 0x9c, 0x5c, 0x2c, 0xe8,
  98         0xd9, 0x06, 0xd4, 0xc3, 0x05, 0x94, 0x1c, 0x7b, 0x23, 0x89, 0x86, 0x1d,
  99         0x32, 0xbb, 0x23, 0x90, 0x2b, 0x72, 0xd7, 0x90, 0x53, 0x52, 0x10, 0x12,
 100         0xd0, 0xc2, 0xe2, 0x72, 0x81, 0x70, 0x3c, 0xb1, 0x27, 0x42, 0xec, 0xbf,
 101         0x2b, 0x54, 0xd6, 0xcb, 0x61, 0xea, 0xb4, 0xd4, 0xa8, 0xde, 0xf3, 0xdf,
 102         0x3d, 0xd1, 0x17, 0xde, 0x86, 0x89, 0xf4, 0xa1, 0x28, 0x5e, 0xda, 0xb4,
 103         0x47, 0x19, 0x9b, 0xc2, 0xce, 0x49, 0xea, 0x63, 0xda, 0x42, 0x1c, 0x85,
 104         0x1c, 0xab, 0x6c, 0xd7, 0xc2, 0xfd, 0x34, 0x1b, 0xd5, 0x11, 0xa2, 0x44,
 105         0xb7, 0x7a, 0x85, 0x61, 0x03, 0xba, 0xd4, 0x64, 0xe1, 0x49, 0x87, 0x92,
 106         0xe6, 0xdc, 0x39, 0x94, 0x9c, 0xba, 0xef, 0x58, 0x9e, 0x0e, 0x36, 0x98,
 107         0xd7, 0xd2, 0x4c, 0x14, 0x71, 0x94, 0x78, 0xaf, 0x86, 0xe7, 0x2f, 0xe9,
 108         0xf9, 0x20, 0x4d, 0xfe, 0xda, 0xd7, 0x3f, 0x89, 0xc1, 0x59, 0xae, 0xbd,
 109         0x60, 0x9b, 0x97, 0xa4, 0x66, 0x00, 0xbb, 0x7b, 0xd0, 0x49, 0x85, 0x6f,
 110         0x7b, 0x01, 0x24, 0xc3, 0x48, 0xe2, 0xc7, 0x61, 0x98, 0x9c, 0xe5, 0x93,
 111         0x87, 0x04, 0x09, 0x3a, 0x92, 0x54, 0x1f, 0xb5, 0x80, 0x29, 0x15, 0xe5,
 112         0x7f, 0xfe, 0xdc, 0xaf, 0xd3, 0xe1, 0x62, 0xc4, 0xb6, 0xdb, 0x2f, 0x1a,
 113         0x08, 0xf3, 0x54, 0x06, 0x3a, 0xce, 0x5e, 0x89, 0x71, 0xdf, 0x3b, 0x5c,
 114         0x8c, 0x6b, 0x83, 0xa9, 0x0c, 0x05, 0x50, 0x7b, 0x84, 0x09, 0x18, 0x66,
 115         0x84, 0xe1, 0x7e, 0x60, 0xd6, 0xdc, 0xbf, 0x1c, 0xac, 0x5c, 0xdc, 0xe6,
 116         0x4c, 0x9e, 0xa0, 0x4a, 0x59, 0x30, 0xff, 0x91, 0x90, 0x1e, 0x21, 0x29,
 117         0x50, 0x99, 0x76, 0xfd, 0x2f, 0x5a, 0x67, 0x6a, 0x00, 0x6b, 0x40, 0x27,
 118         0xe7, 0xbd, 0x17, 0xe6, 0x5f, 0x9e, 0xe4, 0x6b, 0xe0, 0x05, 0x9e, 0x7d,
 119         0xcb, 0x90, 0xe9, 0x3c, 0x9c, 0x79, 0xc9, 0x47, 0xf8, 0x58, 0xbc, 0x3f,
 120         0xb1, 0xa5, 0xef, 0x67, 0xf0, 0x22, 0xa1, 0x70, 0x33, 0x36, 0xb0, 0x5c,
 121         0xed, 0xea, 0x4e, 0xde, 0x24, 0x0c, 0x5b, 0xd8, 0x4d, 0xbe, 0xac, 0x6a,
 122         0x12, 0x31, 0xa6, 0x5e, 0x5f, 0x04, 0xb6, 0x58, 0xa1, 0xd1, 0x29, 0xa3,
 123         0x33, 0x9c, 0x64, 0xb1, 0x8e, 0x3b, 0xfa, 0xaf, 0x35, 0x94, 0x7a, 0xa4,
 124         0xf5, 0xcb, 0x9e, 0x67, 0x1b, 0x8d, 0x35, 0xca, 0x10, 0x69, 0x8d, 0xea,
 125         0x78, 0xc2, 0xf6, 0x63, 0xc0, 0x11, 0xf1, 0xf6, 0x66, 0x70, 0x2e, 0x96,
 126         0xf0, 0xbc, 0x7b, 0x1e, 0x16, 0x26, 0xde, 0xe3, 0x7f, 0xc0, 0xf4, 0x6c,
 127         0x3c, 0x0b, 0x52, 0xe2, 0x07, 0xde, 0x70, 0x8b, 0xaf, 0x84, 0x95, 0x1b,
 128         0x46, 0x95, 0x69, 0x05, 0x92, 0xea, 0x36, 0xa5, 0xca, 0x50, 0xdb, 0x49,
 129         0xc8, 0x44, 0xee, 0x7c, 0x49, 0x40, 0x34, 0x05, 0xf3, 0x06, 0x1f, 0x1c,
 130         0xcc, 0x78, 0x62, 0x1b, 0x9d, 0xe2, 0x4f, 0x3e, 0x04, 0x96, 0xba, 0xd0,
 131         0xc7, 0xa2, 0x3a, 0xaa, 0xf7, 0xc3, 0xae, 0xc0, 0x6b, 0xca, 0xc8, 0x59,
 132         0x90, 0xe0, 0x45, 0x7b, 0x4b, 0x60, 0xbf, 0xae, 0x15, 0x25, 0xd0, 0xa2,
 133         0x2f, 0x95, 0x6a, 0x2e, 0x37, 0x24, 0x15, 0x69, 0x0e, 0x3a, 0x6d, 0x40,
 134         0x21, 0xf6, 0x74, 0x5c, 0xa6, 0x9f, 0xe0, 0x03, 0x60, 0x04, 0x59, 0x70,
 135         0x70, 0xa0, 0x46, 0xf4, 0xdf, 0x0a, 0x4b, 0x14, 0xab, 0x87, 0x0c, 0xaa,
 136         0x64, 0x9b, 0x82, 0xca, 0x21, 0xb0, 0x72, 0xfa, 0x8b, 0x37, 0xf5, 0x60,
 137         0xd7, 0xb7, 0x4e, 0x72, 0x5e, 0x13, 0x23, 0x73, 0x84, 0x6c, 0xd1, 0x8d,
 138         0x72, 0xa2, 0x15, 0x8b, 0x51, 0x38, 0x90, 0x68, 0x90, 0xd9, 0x8b, 0x65,
 139         0x30, 0x61, 0xdb, 0x51, 0x80, 0x58, 0xdd, 0xc3, 0xf0, 0x29, 0x33, 0xdc,
 140         0x39, 0x92, 0xbf, 0x27, 0xe6, 0xc7, 0x82, 0xf6, 0xea, 0xcf, 0x21, 0xd2,
 141         0xa0, 0x38, 0x02, 0x57, 0x52, 0xf5, 0xdd, 0x07, 0x99, 0xe3, 0x09, 0xd7,
 142         0xad, 0x9e, 0x1e, 0xe7, 0xf3, 0x5e, 0x72, 0xa0, 0xc6, 0x9d, 0x41, 0x86,
 143         0x96, 0x82, 0x74, 0x46, 0x1f, 0x05, 0xd2, 0x05, 0x25, 0x29, 0x27, 0x66,
 144         0xe1, 0xab, 0x5c, 0x06, 0xf4, 0xac, 0xe7, 0xd0, 0xf8, 0xe6, 0x5e, 0x8b,
 145         0x19, 0x55, 0xc2, 0x99, 0x8e, 0xa7, 0x2e, 0x66, 0x0c, 0x2a, 0x61, 0xb0,
 146         0x98, 0x41, 0x93, 0x05, 0x54, 0x90, 0xaa, 0xbe, 0x15, 0x26, 0x5b, 0x77,
 147         0x7c, 0xb0, 0xf8, 0x08, 0x68, 0xb6, 0xb8, 0xd4, 0xdd, 0xd8, 0xa8, 0x4f,
 148         0xdd, 0xf6, 0x93, 0xe5, 0xa1, 0x88, 0x1b, 0x7a, 0x05, 0x81, 0xc5, 0x98,
 149         0x34, 0x1d, 0x88, 0x63, 0x55, 0xaf, 0x9a, 0xa1, 0xcb, 0x4b, 0xaf, 0x86,
 150         0xb3, 0x45, 0xda, 0xa4, 0xb4, 0xa5, 0x10, 0x7a, 0x50, 0x6a, 0xe5, 0xda,
 151         0x6f, 0x8f, 0xc0, 0x1d, 0x95, 0xb1, 0x91, 0x48, 0x53, 0xc3, 0xe5, 0x1f,
 152         0x0e, 0x05, 0x75, 0xaa, 0xc7, 0xd8, 0x36, 0xd0, 0x6d, 0x50, 0x48, 0xd4,
 153         0xe6, 0xbd, 0xd0, 0x2d, 0x97, 0x17, 0x2d, 0xb3, 0x46, 0xab, 0x19, 0x0e,
 154         0xe4, 0xac, 0xfd, 0x93, 0xab, 0x0c, 0x4c, 0xad, 0xbf, 0x58, 0x1b, 0xaa,
 155         0x26, 0xcd, 0x0d, 0xda, 0xaf, 0xcb, 0xeb, 0xb0, 0x19, 0x5c, 0x46, 0x1f,
 156         0x9b, 0xb0, 0xb8, 0x12, 0x6c, 0xa7, 0x4e, 0xb8, 0xa7, 0x1f, 0x12, 0x6b,
 157         0xf8, 0xbe, 0x4b, 0xa9, 0x04, 0xb4, 0xf9, 0x36, 0xcc, 0xd9, 0xd5, 0x91,
 158         0xac, 0x7e, 0xe9, 0x13, 0xc0, 0x7f, 0xca, 0xd7, 0xdc, 0xbe, 0xa9, 0xb0,
 159         0xd6, 0x28, 0x17, 0x2f, 0xd6, 0xdf, 0x0e, 0x6b, 0x48, 0x11, 0xd6, 0x51,
 160         0xc7, 0x6d, 0x87, 0xf6, 0x08, 0xb7, 0x6c, 0x69, 0xf7, 0xd6, 0x28, 0x50,
 161         0x7e, 0x74, 0xad, 0x96, 0x6a, 0x0c, 0xca, 0x6b, 0xb1, 0xf1, 0xde, 0xa3,
 162         0x5f, 0x23, 0xf5, 0x2a, 0x44, 0x11, 0x0f, 0xa3, 0xf7, 0x24, 0x36, 0x1b,
 163         0x33, 0xe6, 0x7e, 0xd9, 0x0e, 0xa5, 0x8b, 0xa0, 0xb8, 0x8b, 0x85, 0xee,
 164         0xd0, 0xe4, 0x69, 0x43, 0xc6, 0xf9, 0x5f, 0x27, 0xa5, 0xc9, 0x61, 0x3b,
 165         0x8e, 0xaf, 0x62, 0x77, 0x42, 0xb6, 0x27, 0x5f, 0xed, 0x96, 0x86, 0xb3,
 166         0xef, 0x32, 0x31, 0x43, 0x2e, 0x7b, 0xaf, 0x5b, 0xe2, 0x75, 0x82, 0x72,
 167         0xad, 0x3b, 0x5d, 0x92, 0xc1, 0x15, 0xaa, 0xfb, 0x21, 0x07, 0xe9, 0xaa,
 168         0xc4, 0xe2, 0xd7, 0x99, 0x83, 0x6c, 0x72, 0x39, 0x6f, 0x35, 0x20, 0x9d,
 169         0xe0, 0xd8, 0xf8, 0xdb, 0x72, 0x24, 0xe5, 0x8d, 0x29, 0xfd, 0x24, 0x7b,
 170         0xbc, 0x48, 0xe9, 0xbb, 0xc2, 0x84, 0xc7, 0xb9
 171 };
 172 static unsigned int keyblock_len = sizeof(keyblock);
 173
 174 /*
 175  * RSA 2048-bit key from vboot_reference:
 176  * tests/devkeys/kernel_data_key.vbprivk, minus the 8-byte custom header.
 177  */
 178 static const unsigned char privk[] = {
 179         0x30, 0x82, 0x04, 0xa3, 0x02, 0x01, 0x00, 0x02, 0x82, 0x01, 0x01, 0x00,
 180         0xcb, 0xd6, 0x54, 0x2b, 0xbf, 0xec, 0x42, 0x27, 0xb1, 0x3c, 0x70, 0x81,
 181         0x72, 0xe2, 0xc2, 0xd0, 0x12, 0x10, 0x52, 0x53, 0x90, 0xd7, 0x72, 0x2b,
 182         0x90, 0x23, 0xbb, 0x32, 0x1d, 0x86, 0x89, 0x23, 0x7b, 0x1c, 0x94, 0x05,
 183         0xc3, 0xd4, 0x06, 0xd9, 0xe8, 0x2c, 0x5c, 0x9c, 0x66, 0x4b, 0x38, 0xe3,
 184         0x10, 0x04, 0x14, 0x45, 0x26, 0x7d, 0x49, 0xa8, 0xa2, 0x98, 0x86, 0x65,
 185         0xfe, 0x2c, 0x3d, 0xe4, 0x1c, 0x76, 0xda, 0xda, 0xda, 0xd3, 0x6a, 0x37,
 186         0x88, 0xa2, 0xe5, 0x20, 0x11, 0x96, 0x40, 0x6b, 0x05, 0x02, 0xc5, 0x0a,
 187         0x5f, 0x09, 0xc6, 0xe6, 0x20, 0xc6, 0x01, 0xc6, 0x54, 0x08, 0x0b, 0x1e,
 188         0xb4, 0xa9, 0x3f, 0xc9, 0x67, 0x81, 0xd9, 0x2b, 0xd0, 0xdc, 0x7d, 0xa7,
 189         0x97, 0x6f, 0x8b, 0x78, 0x33, 0xb7, 0xd7, 0x52, 0x2a, 0x41, 0x69, 0x48,
 190         0x69, 0x96, 0x8f, 0xc5, 0x0a, 0x1b, 0x06, 0x88, 0x1f, 0xfb, 0xe8, 0xb0,
 191         0x97, 0xbd, 0x6d, 0x3d, 0x28, 0x82, 0xfe, 0xd5, 0x6e, 0xa1, 0x57, 0x1e,
 192         0xcb, 0x43, 0x7e, 0xba, 0x11, 0x8c, 0xc5, 0x6a, 0xf0, 0x92, 0x53, 0x7b,
 193         0xb2, 0x21, 0x26, 0xdb, 0xf8, 0x8c, 0x5a, 0x1b, 0x9f, 0x1d, 0x81, 0xa9,
 194         0xea, 0xa4, 0xa6, 0x83, 0xd6, 0xd1, 0xcc, 0x8a, 0xdb, 0xaf, 0x99, 0x64,
 195         0x6c, 0x9d, 0x8b, 0x83, 0xd1, 0x82, 0x44, 0xe7, 0x3a, 0xb4, 0x9f, 0x71,
 196         0xd0, 0xaf, 0x15, 0x72, 0x6d, 0x1c, 0x2e, 0x43, 0x8c, 0x7d, 0x4e, 0x01,
 197         0xe9, 0x70, 0xcc, 0x59, 0xc7, 0xbd, 0x65, 0x2a, 0xf0, 0x2c, 0x88, 0x46,
 198         0x5a, 0x67, 0xaf, 0xaf, 0x8a, 0x16, 0x98, 0x5e, 0x5b, 0x3d, 0xba, 0x94,
 199         0x0c, 0x65, 0x03, 0x9c, 0x1d, 0x78, 0xfe, 0x21, 0x12, 0xa5, 0x72, 0x3a,
 200         0xc2, 0xc4, 0x22, 0xdc, 0xca, 0x1b, 0x9b, 0xa7, 0xcc, 0xcc, 0x53, 0x6d,
 201         0x0f, 0x86, 0x2d, 0x1d, 0x02, 0x03, 0x01, 0x00, 0x01, 0x02, 0x82, 0x01,
 202         0x00, 0x4d, 0xb8, 0xea, 0x9d, 0x47, 0xef, 0xf1, 0x05, 0xab, 0x79, 0xed,
 203         0x38, 0x1e, 0xb3, 0x42, 0x2f, 0x0e, 0x44, 0x34, 0xef, 0xf2, 0x31, 0x84,
 204         0x32, 0x02, 0x22, 0xed, 0xb4, 0xdd, 0x37, 0x38, 0x41, 0x54, 0x27, 0x00,
 205         0x75, 0xf6, 0x46, 0x79, 0x5a, 0x4b, 0x41, 0xe7, 0x0a, 0x27, 0xa3, 0x15,
 206         0x0c, 0xd7, 0x45, 0x86, 0xe9, 0x1b, 0x14, 0xf8, 0xaa, 0x19, 0x5d, 0x69,
 207         0x19, 0xa8, 0xc1, 0xfb, 0xd3, 0x67, 0xdb, 0x15, 0xf6, 0x0f, 0x2c, 0x3f,
 208         0xba, 0xef, 0x19, 0x95, 0x9e, 0x15, 0xb6, 0xa1, 0xd7, 0x6c, 0xb0, 0xb2,
 209         0xab, 0x12, 0xb3, 0xea, 0xa8, 0x42, 0xe4, 0xdd, 0x36, 0x5f, 0x42, 0x35,
 210         0xe3, 0x3e, 0x65, 0xae, 0x91, 0xc0, 0x2a, 0xed, 0xc0, 0xdc, 0x41, 0xc6,
 211         0x93, 0xc9, 0x95, 0x59, 0xab, 0xba, 0xa4, 0xa5, 0xb0, 0x89, 0xb6, 0x29,
 212         0x4b, 0xd8, 0x1e, 0xf5, 0xb0, 0xde, 0xfa, 0x91, 0x11, 0x55, 0xd6, 0x9d,
 213         0xe1, 0xa7, 0x9c, 0xf2, 0xf4, 0x9d, 0x7f, 0x96, 0x49, 0x7a, 0xab, 0xe9,
 214         0x9a, 0x0c, 0xcb, 0x10, 0x5c, 0x67, 0xf0, 0x1d, 0xf3, 0x33, 0x84, 0xae,
 215         0x6e, 0xe4, 0xbb, 0xa7, 0x57, 0x98, 0x99, 0x2b, 0xf3, 0x1d, 0xab, 0xec,
 216         0x01, 0xa2, 0x2e, 0x3c, 0x10, 0x5c, 0xff, 0xe8, 0xcc, 0x50, 0x45, 0x21,
 217         0x2f, 0x04, 0x69, 0xdd, 0x02, 0x5b, 0x10, 0xd6, 0x54, 0x36, 0x4c, 0x73,
 218         0x0c, 0x1e, 0xc1, 0xff, 0xac, 0x60, 0x5d, 0xbc, 0x13, 0x84, 0xe8, 0xa4,
 219         0xbd, 0x66, 0xca, 0xca, 0xaf, 0x55, 0x8a, 0xf8, 0x87, 0x17, 0x93, 0xbf,
 220         0x66, 0xa4, 0x97, 0xe9, 0x47, 0x81, 0x03, 0xfa, 0x4c, 0x32, 0xf6, 0xec,
 221         0x7a, 0x03, 0xbb, 0x2d, 0x3b, 0x9b, 0xea, 0xdc, 0x6c, 0x61, 0x7f, 0x05,
 222         0xc8, 0x2d, 0x50, 0x89, 0xe9, 0x10, 0x3d, 0x3c, 0x02, 0xb0, 0x5d, 0x3e,
 223         0x25, 0x71, 0xd2, 0xa1, 0xe1, 0x02, 0x81, 0x81, 0x00, 0xf6, 0x3c, 0x7f,
 224         0x15, 0x63, 0x04, 0x0a, 0xd4, 0x68, 0xe8, 0xd9, 0x4b, 0x7f, 0xbc, 0xca,
 225         0xb5, 0x84, 0x01, 0x71, 0x11, 0x33, 0x4d, 0xe1, 0x0a, 0xe8, 0xa7, 0x95,
 226         0xcc, 0x23, 0x59, 0x19, 0xb5, 0x82, 0xaa, 0xae, 0xe4, 0x90, 0x33, 0x95,
 227         0x20, 0x1a, 0xfd, 0xef, 0x8e, 0x36, 0xc1, 0x57, 0xde, 0x94, 0xdd, 0x99,
 228         0x6f, 0x14, 0x0c, 0x8e, 0x30, 0xe0, 0xe7, 0x64, 0x33, 0xa7, 0x1d, 0xfd,
 229         0x99, 0xdc, 0x58, 0x49, 0x4e, 0x56, 0x82, 0x43, 0xea, 0xd9, 0xf7, 0xcc,
 230         0x1a, 0xf5, 0x09, 0x38, 0x4c, 0xf6, 0x87, 0x8f, 0xa6, 0x40, 0x96, 0xd1,
 231         0x81, 0x62, 0xbb, 0x49, 0x53, 0x69, 0x56, 0xdf, 0x4a, 0x85, 0xfd, 0x72,
 232         0x34, 0x21, 0x56, 0xa3, 0x7b, 0xda, 0x50, 0x24, 0x88, 0xc6, 0x0b, 0x03,
 233         0x94, 0x0d, 0xe2, 0x03, 0x2a, 0x3c, 0x5a, 0xdd, 0x73, 0xe7, 0x07, 0x01,
 234         0x7d, 0xdd, 0x38, 0x81, 0x19, 0x02, 0x81, 0x81, 0x00, 0xd3, 0xeb, 0x72,
 235         0x3f, 0xf6, 0x9b, 0x03, 0x8c, 0xab, 0xd9, 0x41, 0x47, 0xbe, 0x6c, 0x07,
 236         0x7f, 0xd7, 0xcb, 0xee, 0xbf, 0x45, 0x13, 0x1e, 0x53, 0x35, 0xd2, 0xe4,
 237         0x6a, 0x13, 0xe9, 0xd8, 0xe3, 0xf4, 0x28, 0x5e, 0xeb, 0xd8, 0xd2, 0x87,
 238         0x60, 0xdc, 0xa7, 0x21, 0xd8, 0x33, 0xce, 0xca, 0x60, 0x50, 0x1b, 0x87,
 239         0xbf, 0x71, 0x88, 0x90, 0x71, 0x6f, 0xde, 0xdb, 0x33, 0x1d, 0x3c, 0xb1,
 240         0x2f, 0x1b, 0x41, 0xb8, 0x55, 0xa1, 0x5c, 0xa8, 0xb2, 0x73, 0x1b, 0x39,
 241         0x69, 0x5c, 0xa1, 0x57, 0x9b, 0x2e, 0xcd, 0x0d, 0x71, 0x42, 0xdf, 0x2a,
 242         0xd3, 0x4f, 0x51, 0xdc, 0x35, 0x5c, 0x14, 0x86, 0x16, 0xb8, 0x22, 0x8c,
 243         0x73, 0x37, 0x7a, 0x6c, 0xb7, 0xfe, 0x01, 0x1b, 0xa8, 0xc5, 0xf1, 0xff,
 244         0xda, 0xd4, 0x63, 0x58, 0x81, 0xe1, 0x6a, 0xaf, 0xc2, 0x3d, 0xbb, 0x17,
 245         0x3f, 0x2c, 0xf9, 0xb8, 0xa5, 0x02, 0x81, 0x81, 0x00, 0xd1, 0x1e, 0x6b,
 246         0xa7, 0x54, 0x22, 0x18, 0xb8, 0x70, 0x28, 0x60, 0x72, 0x98, 0x17, 0x53,
 247         0xe8, 0x78, 0x25, 0x69, 0x4a, 0xfc, 0x51, 0x45, 0xb0, 0x28, 0x0a, 0x3b,
 248         0x53, 0xd5, 0x29, 0x54, 0x86, 0x2c, 0x64, 0x9c, 0x87, 0x8c, 0x57, 0xe2,
 249         0x6c, 0x13, 0xc0, 0x59, 0x74, 0x63, 0xd8, 0x2b, 0xb1, 0xe2, 0xa7, 0x98,
 250         0x29, 0x17, 0xd3, 0xd9, 0xe6, 0x74, 0xfa, 0xce, 0xc4, 0x77, 0x47, 0x27,
 251         0x1b, 0x46, 0x60, 0xcc, 0x50, 0xf5, 0x73, 0x48, 0x0e, 0xe9, 0xf2, 0x62,
 252         0xaa, 0xfa, 0x33, 0x4c, 0x57, 0x40, 0x7f, 0xbc, 0x65, 0xab, 0x30, 0xea,
 253         0xd8, 0x81, 0x6b, 0x21, 0x48, 0xef, 0x8b, 0x51, 0xb3, 0x4e, 0xbc, 0x02,
 254         0x03, 0x77, 0xd4, 0xc6, 0x9e, 0xe6, 0xb7, 0x6d, 0x6f, 0xa3, 0x11, 0xb3,
 255         0x86, 0x47, 0x8c, 0x0c, 0xb8, 0x0f, 0xed, 0xf3, 0x68, 0xfd, 0x69, 0x9b,
 256         0xc0, 0xb2, 0xe1, 0xcb, 0xf1, 0x02, 0x81, 0x80, 0x46, 0xc6, 0xdb, 0xe1,
 257         0x80, 0xfb, 0x44, 0xb4, 0x36, 0xb0, 0xd8, 0x9c, 0x9d, 0x7c, 0x77, 0x04,
 258         0xbb, 0x8d, 0xe0, 0xaf, 0x00, 0xe2, 0xe1, 0xbd, 0xe8, 0xbc, 0x06, 0x8d,
 259         0x67, 0x19, 0x32, 0xd6, 0xef, 0x34, 0x8c, 0x7f, 0x38, 0x6b, 0x17, 0xcb,
 260         0xc1, 0xe6, 0x0f, 0xe7, 0xa5, 0x65, 0xeb, 0x31, 0x3f, 0x8f, 0xf2, 0x46,
 261         0x7e, 0x24, 0x9e, 0x19, 0x44, 0xc3, 0xa9, 0x71, 0xe8, 0xd1, 0xdc, 0x5b,
 262         0x5f, 0x3f, 0x13, 0xd1, 0x85, 0x92, 0xec, 0xc4, 0xac, 0xac, 0xea, 0xff,
 263         0xc5, 0x70, 0x1d, 0x52, 0x36, 0xcf, 0x45, 0x2e, 0x0e, 0xa7, 0x7a, 0x26,
 264         0x18, 0xd7, 0xbe, 0x34, 0x14, 0x0c, 0xc6, 0xbb, 0xcf, 0xc3, 0xba, 0x24,
 265         0xc0, 0xe2, 0xa2, 0x6c, 0xd0, 0xe8, 0x8d, 0xd4, 0x50, 0x48, 0x02, 0xab,
 266         0x93, 0x43, 0x9a, 0xcb, 0xc5, 0xfd, 0x5b, 0xb6, 0x03, 0xe7, 0xf8, 0x5b,
 267         0xa1, 0x29, 0xc6, 0x01, 0x02, 0x81, 0x80, 0x0e, 0x18, 0xbc, 0x00, 0xa3,
 268         0x81, 0xda, 0xc2, 0xc8, 0xfb, 0x0a, 0xbd, 0x7f, 0xb7, 0x7f, 0xa1, 0x18,
 269         0x7f, 0x49, 0xb8, 0x32, 0x83, 0x4b, 0x71, 0x35, 0x59, 0x51, 0x7b, 0xee,
 270         0x8e, 0x4e, 0xd2, 0x42, 0xa8, 0x6c, 0x82, 0x57, 0xf7, 0x34, 0xf6, 0x82,
 271         0x59, 0xe9, 0x75, 0x7a, 0x8f, 0x0a, 0x8d, 0x46, 0x1e, 0xa1, 0x77, 0xa1,
 272         0x4c, 0xb3, 0x9e, 0x86, 0x93, 0x18, 0xdf, 0x3e, 0xfb, 0x81, 0xd0, 0xbc,
 273         0x65, 0xa2, 0xb3, 0x80, 0xf0, 0x8f, 0x73, 0x2f, 0xb5, 0xc4, 0xc0, 0x03,
 274         0xac, 0x24, 0xfa, 0x4f, 0x05, 0xe3, 0x16, 0x29, 0x7c, 0xff, 0x63, 0xd5,
 275         0x0a, 0x0a, 0xbd, 0xd7, 0x65, 0x3a, 0xb5, 0x5e, 0xe7, 0x23, 0xfc, 0x3d,
 276         0x08, 0xea, 0x62, 0xc2, 0xe3, 0x4a, 0xbb, 0x86, 0x5a, 0xc5, 0x93, 0xd7,
 277         0xbc, 0xb4, 0x4c, 0xcf, 0xcf, 0x78, 0x9f, 0x52, 0x6e, 0xa1, 0x49, 0x21,
 278         0xf7, 0x20, 0x42
 279 };
 280 static const unsigned int privk_len = sizeof(privk);
 281
 282 /* Signature data (a secure hash, possibly signed) */
 283 struct vb2_signature {
 284         /* Offset of signature data from start of this struct */
 285         uint32_t sig_offset;
 286         uint32_t reserved0;
 287
 288         /* Size of signature data in bytes */
 289         uint32_t sig_size;
 290         uint32_t reserved1;
 291
 292         /* Size of the data block which was signed in bytes */
 293         uint32_t data_size;
 294         uint32_t reserved2;
 295 } __attribute__((packed));
 296
 297 /*
 298  * Preamble block for kernel, version 2.2
 299  *
 300  * This should be followed by:
 301  *   1) The signature data for the kernel body, pointed to by
 302  *      body_signature.sig_offset.
 303  *   2) The signature data for (vb2_kernel_preamble + body signature data),
 304  *       pointed to by preamble_signature.sig_offset.
 305  *   3) The 16-bit vmlinuz header, which is used for reconstruction of
 306  *      vmlinuz image.
 307  */
 308 struct vb2_kernel_preamble {
 309         /*
 310          * Size of this preamble, including keys, signatures, vmlinuz header,
 311          * and padding, in bytes
 312          */
 313         uint32_t preamble_size;
 314         uint32_t reserved0;
 315
 316         /* Signature for this preamble (header + body signature) */
 317         struct vb2_signature preamble_signature;
 318
 319         /* Version of this header format */
 320         uint32_t header_version_major;
 321         uint32_t header_version_minor;
 322
 323         /* Kernel version */
 324         uint32_t kernel_version;
 325         uint32_t reserved1;
 326
 327         /* Load address for kernel body */
 328         uint64_t body_load_address;
 329
 330         /* Address of bootloader, after body is loaded at body_load_address */
 331         uint64_t bootloader_address;
 332
 333         /* Size of bootloader in bytes */
 334         uint32_t bootloader_size;
 335         uint32_t reserved2;
 336
 337         /* Signature for the kernel body */
 338         struct vb2_signature body_signature;
 339
 340         /* Address of 16-bit header for vmlinuz reassembly. */
 341         uint64_t vmlinuz_header_address;
 342
 343         /* Size of 16-bit header for vmlinuz in bytes. */
 344         uint32_t vmlinuz_header_size;
 345         uint32_t reserved3;
 346
 347         uint32_t flags;
 348 } __attribute__((packed));
 349
 350 /*
 351  * Order matters. |data| may overlap with |siginfo|, so we need to fill out
 352  * |siginfo| before computing the signature.
 353  */
 354 static int sign(const void *data, size_t len, struct vb2_signature *siginfo,
 355                 void *sigout)
 356 {
 357         unsigned char hash[SHA256_DIGEST_LENGTH];
 358         SHA256_CTX sha256;
 359         int ret;
 360
 361         memset(siginfo, 0, sizeof(*siginfo));
 362         siginfo->sig_offset = (uintptr_t)(void *)sigout - (uintptr_t)(void *)siginfo;
 363         siginfo->sig_size = SIG_SIZE;
 364         siginfo->data_size = len;
 365
 366         const unsigned char *p = privk;
 367         char digest_info[] = {
 368                 0x30, 0x31, 0x30, 0x0d, 0x06, 0x09, 0x60, 0x86, 0x48, 0x01,
 369                 0x65, 0x03, 0x04, 0x02, 0x01, 0x05, 0x00, 0x04, 0x20,
 370         };
 371
 372         uint8_t digest[sizeof(digest_info) + sizeof(hash)];
 373
 374         SHA256_Init(&sha256);
 375         SHA256_Update(&sha256, data, len);
 376         SHA256_Final(hash, &sha256);
 377
 378         memcpy(digest, digest_info, sizeof(digest_info));
 379         memcpy(digest + sizeof(digest_info), hash, sizeof(hash));
 380
 381         RSA *key = d2i_RSAPrivateKey(0, &p, privk_len);
 382         if (!key) {
 383                 fprintf(stderr, "Failed d2i_RSAPrivateKey()\n");
 384                 return -1;
 385         }
 386
 387         ret = RSA_private_encrypt(sizeof(digest), digest, sigout, key,
 388                                   RSA_PKCS1_PADDING);
 389         if (ret == -1) {
 390                 fprintf(stderr, "%s: RSA_private_encrypt() failed\n", __func__);
 391                 return -1;
 392         }
 393
 394         return 0;
 395 }
 396
 397 static struct vb2_kernel_preamble *
 398 generate_preamble(const void *kblob, size_t kblob_len,
 399                   size_t kernel_len, size_t config_len)
 400 {
 401         struct vb2_kernel_preamble *h;
 402         uint32_t signed_size = sizeof(struct vb2_kernel_preamble) + SIG_SIZE;
 403         uint32_t block_size = signed_size + SIG_SIZE;
 404         int ret;
 405
 406         if (block_size + keyblock_len < BLOCK_PAD)
 407                 block_size = BLOCK_PAD - keyblock_len;
 408         h = (struct vb2_kernel_preamble *)calloc(block_size, 1);
 409         if (!h) {
 410                 perror("calloc");
 411                 return NULL;
 412         }
 413
 414         /* Sign the body, place the signature in the preamble */
 415         ret = sign(kblob, kblob_len, &h->body_signature, h + 1);
 416         if (ret) {
 417                 fprintf(stderr, "sign() failed: %d\n", ret);
 418                 return NULL;
 419         }
 420
 421         h->header_version_major = 2;
 422         h->header_version_minor = 2;
 423         h->preamble_size = block_size;
 424         h->kernel_version = 1;
 425         h->body_load_address = 0x100000;
 426         /*
 427          * "Bootloder" area (currently empty) is after kernel + config +
 428          * parameter page.
 429          */
 430         h->bootloader_address = h->body_load_address +
 431                                 ROUNDUP(kernel_len) +
 432                                 ROUNDUP(config_len) +
 433                                 ALIGN;
 434         h->bootloader_size = 0x1000;
 435         h->vmlinuz_header_address = 0;
 436         h->vmlinuz_header_size = 0;
 437         h->flags = 0;
 438
 439         ret = sign(h, signed_size, &h->preamble_signature,
 440                    (void *)(h + 1) + SIG_SIZE);
 441         if (ret) {
 442                 fprintf(stderr, "failed to sign preamble: %d\n", ret);
 443                 return NULL;
 444         }
 445         return h;
 446 }
 447
 448
 449 /*
 450  * Distilled from vboot_reference futility/cmd_vbutil_kernel.c pack command.
 451  *
 452  * NB: "config" is the kernel cmdline
 453  */
 454 static int vbutil_pack(const char *kernel, size_t kernel_len,
 455                        const char *config, size_t config_len,
 456                        void **out, size_t *out_len)
 457 {
 458         size_t kblob_len = ROUNDUP(kernel_len) + ROUNDUP(config_len) + ALIGN + ALIGN;
 459         void *kblob = malloc(kblob_len);
 460         if (!kblob) {
 461                 perror("malloc");
 462                 return -1;
 463         }
 464         void *kp = kblob;
 465         memset(kblob, 0, kblob_len);
 466
 467         /* Kernel */
 468         memcpy(kp, kernel, kernel_len);
 469         kp += ROUNDUP(kernel_len);
 470
 471         /* Kernel command line */
 472         memcpy(kp, config, config_len);
 473         kp += ROUNDUP(config_len);
 474
 475         /* "Parameters" -- empty, 4K-aligned */
 476         /* "Bootloader" region -- empty, 4K-aligned */
 477         /* Vmlinuz header -- only for x86 (not currently supported), empty */
 478
 479         struct vb2_kernel_preamble *h;
 480         h = generate_preamble(kblob, kblob_len, kernel_len, config_len);
 481         if (!h) {
 482                 fprintf(stderr, "Failed to generate preamble\n");
 483                 return -1;
 484         }
 485         size_t outlen = sizeof(keyblock) + h->preamble_size + kblob_len;
 486         void *outbuf = malloc(outlen);
 487         if (!outbuf)
 488                 return -1;
 489
 490         void *p = outbuf;
 491         memcpy(p, keyblock, sizeof(keyblock));
 492         p += sizeof(keyblock);
 493
 494         memcpy(p, h, h->preamble_size);
 495         p += h->preamble_size;
 496
 497         memcpy(p, kblob, kblob_len);
 498         p += kblob_len;
 499
 500         if (outbuf) {
 501                 *out = outbuf;
 502                 *out_len = outlen;
 503         }
 504
 505         return 0;
 506 }
 507
 508 static void * read_file(const char *path, size_t *out_len)
 509 {
 510         struct stat st;
 511         int fd = open(path, O_RDONLY);
 512         if (fd == -1) {
 513                 perror("failed to open");
 514                 return NULL;
 515         }
 516
 517         if (fstat(fd, &st) < 0) {
 518                 perror("fstat");
 519                 return NULL;
 520         }
 521
 522         size_t len = st.st_size;
 523         void *p = malloc(len);
 524         if (!p)
 525                 return NULL;
 526
 527         size_t count = 0;
 528         while (count < len) {
 529                 ssize_t ret = read(fd, p + count, len - count);
 530                 if (ret < 0) {
 531                         perror("read");
 532                         return NULL;
 533                 }
 534                 count += ret;
 535         }
 536
 537         close(fd);
 538
 539         *out_len = len;
 540         return p;
 541 }
 542
 543 int main(int argc, char * const argv[])
 544 {
 545         int ret;
 546         const char *kernel_file = NULL;
 547         const char *out_file = NULL;
 548         const char *cmdline = NULL;
 549         size_t cmdline_len;
 550         void *kernel;
 551         size_t kernel_len;
 552         void *out;
 553         size_t out_len;
 554
 555         int opt;
 556         while ((opt = getopt(argc, argv, "k:c:o:")) != -1) {
 557                 switch (opt) {
 558                 case 'k':
 559                         kernel_file = optarg;
 560                         break;
 561                 case 'c':
 562                         cmdline = optarg;
 563                         break;
 564                 case 'o':
 565                         out_file = optarg;
 566                         break;
 567                 default:
 568                         fprintf(stderr, "Usage [-k <kernel>] [-c <command line>] -o <outfile>\n");
 569                         return -1;
 570                 }
 571         }
 572         if (optind < argc) {
 573                 fprintf(stderr, "Unexpected args?\n");
 574                 return -1;
 575         }
 576         if (!out_file || !cmdline || !kernel_file) {
 577                 fprintf(stderr, "Missing required argument\n");
 578                 return -1;
 579         }
 580
 581         /* Include the \0 terminator */
 582         cmdline_len = strlen(cmdline) + 1;
 583
 584         kernel = read_file(kernel_file, &kernel_len);
 585         if (!kernel) {
 586                 fprintf(stderr, "failed to read kernel file: %s\n", kernel_file);
 587                 return -1;
 588         }
 589
 590         ret = vbutil_pack(kernel, kernel_len, cmdline, cmdline_len, &out, &out_len);
 591         if (ret)
 592                 return ret;
 593
 594         int fd = open(out_file, O_RDWR|O_CREAT, 0644);
 595         if (fd == -1) {
 596                 perror("open");
 597                 return -1;
 598         }
 599
 600         ret = write(fd, out, out_len);
 601         if (ret == -1) {
 602                 perror("write");
 603                 return -1;
 604         }
 605         close(fd);
 606
 607         return 0;
 608 }