T Michael Turney | 540b8ec | 2020-01-24 08:42:47 -0800 | [diff] [blame] | 1 | #!/usr/bin/env python3 |
T Michael Turney | 101098c | 2018-05-01 15:59:37 -0700 | [diff] [blame] | 2 | #============================================================================ |
| 3 | # |
| 4 | #/** @file qgpt.py |
| 5 | # |
| 6 | # GENERAL DESCRIPTION |
| 7 | # Generates QCom GPT header for wrapping Bootblock |
| 8 | # |
| 9 | # Copyright (c) 2018, The Linux Foundation. All rights reserved. |
| 10 | # |
Patrick Georgi | 7051707 | 2020-05-10 18:47:05 +0200 | [diff] [blame] | 11 | # SPDX-License-Identifier: BSD-3-Clause |
| 12 | |
T Michael Turney | 101098c | 2018-05-01 15:59:37 -0700 | [diff] [blame] | 13 | #**/ |
| 14 | # |
| 15 | |
| 16 | import os |
| 17 | import math |
| 18 | import random |
| 19 | import re |
| 20 | import struct |
| 21 | import sys |
| 22 | import tempfile |
| 23 | |
| 24 | from binascii import crc32 |
| 25 | from optparse import OptionParser |
| 26 | from types import * |
| 27 | |
| 28 | |
| 29 | def UpdateMBR(options, GPTBlobBuffer): |
| 30 | i = 0x1BE |
| 31 | GPTBlobBuffer[i + 0] = 0x00 # not bootable |
| 32 | GPTBlobBuffer[i + 1] = 0x00 # head |
| 33 | GPTBlobBuffer[i + 2] = 0x01 # sector |
| 34 | GPTBlobBuffer[i + 3] = 0x00 # cylinder |
| 35 | GPTBlobBuffer[i + 4] = 0xEE # type |
| 36 | GPTBlobBuffer[i + 5] = 0xFF # head |
| 37 | GPTBlobBuffer[i + 6] = 0xFF # sector |
| 38 | GPTBlobBuffer[i + 7] = 0xFF # cylinder |
| 39 | GPTBlobBuffer[i + 8:i + 8 + 4] = [0x01, 0x00, 0x00, 0x00] |
| 40 | |
| 41 | GPTBlobBuffer[i + 12:i + 16] = [0x00, 0x0f, 0x00, 0x00] |
| 42 | |
| 43 | # magic byte for MBR partitioning - always at this location regardless of |
| 44 | # options.sector |
| 45 | GPTBlobBuffer[510:512] = [0x55, 0xAA] |
| 46 | return i |
| 47 | |
| 48 | |
| 49 | def UpdatePartitionEntry(options, GPTBlobBuffer): |
| 50 | |
| 51 | i = 2 * options.sector_size |
| 52 | # GUID of Boot Block |
| 53 | GPTBlobBuffer[i:i + 16] = [0x2c, 0xba, 0xa0, 0xde, 0xdd, 0xcb, 0x05, 0x48, |
| 54 | 0xb4, 0xf9, 0xf4, 0x28, 0x25, 0x1c, 0x3e, 0x98] |
| 55 | i += 16 |
| 56 | |
| 57 | #This is to set Unique Partition GUID. Below Hex Value is : 00ChezaBootblock00 |
| 58 | GPTBlobBuffer[i:i + 16] = [0x00, 0x43, 0x68, 0x65, 0x7a, 0x61, 0x42, 0x6f, |
| 59 | 0x6f, 0x74, 0x62, 0x6c, 0x6f, 0x63, 0x6b, 0x00] |
| 60 | i += 16 |
| 61 | |
| 62 | # LBA of BootBlock Start Content |
| 63 | GPTBlobBuffer[i:i + 8] = [0x03, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00] |
| 64 | i += 8 |
| 65 | |
| 66 | # End LBA of BootBlock Content |
| 67 | GPTBlobBuffer[i] = options.end_lba & 0xFF |
| 68 | GPTBlobBuffer[i+1] = (options.end_lba>>8) & 0xFF |
| 69 | GPTBlobBuffer[i+2] = (options.end_lba>>16) & 0xFF |
| 70 | GPTBlobBuffer[i+3] = (options.end_lba>>24) & 0xFF |
| 71 | GPTBlobBuffer[i+4] = (options.end_lba>>32) & 0xFF |
| 72 | GPTBlobBuffer[i+5] = (options.end_lba>>40) & 0xFF |
| 73 | GPTBlobBuffer[i+6] = (options.end_lba>>48) & 0xFF |
| 74 | GPTBlobBuffer[i+7] = (options.end_lba>>56) & 0xFF |
| 75 | i += 8 |
| 76 | |
| 77 | # Attributes |
| 78 | GPTBlobBuffer[i:i + 8] = [0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00] |
| 79 | i += 8 |
| 80 | |
| 81 | # Label |
| 82 | GPTBlobBuffer[i:i + 17] = [0x62, 0x00, 0x6f, 0x00, 0x6f, 0x00, 0x74, 0x00, |
| 83 | 0x62, 0x00, 0x6c, 0x00, 0x6f, 0x00, 0x63, 0x00, 0x6b] |
| 84 | |
| 85 | return i |
| 86 | |
| 87 | def UpdateGPTHeader(options, GPTBlobBuffer): |
| 88 | |
| 89 | i = options.sector_size |
| 90 | # Signature and Revision and HeaderSize i.e. "EFI PART" and 00 00 01 00 |
| 91 | # and 5C 00 00 00 |
| 92 | GPTBlobBuffer[i:i + 16] = [0x45, 0x46, 0x49, 0x20, 0x50, 0x41, 0x52, 0x54, |
| 93 | 0x00, 0x00, 0x01, 0x00, 0x5C, 0x00, 0x00, 0x00] |
| 94 | i += 16 |
| 95 | |
| 96 | # CRC is zeroed out till calculated later |
| 97 | GPTBlobBuffer[i:i + 4] = [0x00, 0x00, 0x00, 0x00] |
| 98 | i += 4 |
| 99 | |
| 100 | # Reserved, set to 0 |
| 101 | GPTBlobBuffer[i:i + 4] = [0x00, 0x00, 0x00, 0x00] |
| 102 | i += 4 |
| 103 | |
| 104 | # Current LBA |
| 105 | GPTBlobBuffer[i:i + 8] = [0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00] |
| 106 | i += 8 |
| 107 | |
| 108 | # Backup LBA, No Backup Gpt Used |
| 109 | GPTBlobBuffer[i:i + 8] = [0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00] |
| 110 | i += 8 |
| 111 | |
| 112 | # First Usuable LBA (qc_sec + bootblock location) |
| 113 | GPTBlobBuffer[i:i + 8] = [0x03, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00] |
| 114 | i += 8 |
| 115 | |
| 116 | # Last Usuable LBA (qc_sec + bootblock end location) |
| 117 | GPTBlobBuffer[i] = options.end_lba & 0xFF |
| 118 | GPTBlobBuffer[i+1] = (options.end_lba>>8) & 0xFF |
| 119 | GPTBlobBuffer[i+2] = (options.end_lba>>16) & 0xFF |
| 120 | GPTBlobBuffer[i+3] = (options.end_lba>>24) & 0xFF |
| 121 | GPTBlobBuffer[i+4] = (options.end_lba>>32) & 0xFF |
| 122 | GPTBlobBuffer[i+5] = (options.end_lba>>40) & 0xFF |
| 123 | GPTBlobBuffer[i+6] = (options.end_lba>>48) & 0xFF |
| 124 | GPTBlobBuffer[i+7] = (options.end_lba>>56) & 0xFF |
| 125 | i += 8 |
| 126 | |
| 127 | # GUID |
| 128 | GPTBlobBuffer[i:i + 16] = [0x32,0x1B,0x10,0x98,0xE2,0xBB,0xF2,0x4B, |
| 129 | 0xA0,0x6E,0x2B,0xB3,0x3D,0x00,0x0C,0x20] |
| 130 | i += 16 |
| 131 | |
| 132 | # Partition Table Entry LBA |
| 133 | GPTBlobBuffer[i:i + 8] = [0x02, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00] |
| 134 | i += 8 |
| 135 | |
| 136 | # Number of Partition Entries |
| 137 | GPTBlobBuffer[i:i + 4] = [0x01, 0x00, 0x00, 0x00] |
| 138 | i += 4 |
| 139 | |
| 140 | # Size of One Partition Entry |
| 141 | GPTBlobBuffer[i:i + 4] = [0x80, 0x00, 0x00, 0x00] |
| 142 | i += 4 |
| 143 | |
| 144 | # CRC of Partition Entry |
| 145 | |
| 146 | PartEntry = GPTBlobBuffer[options.sector_size*2:options.sector_size*2 + 128] |
Douglas Anderson | 1bdfe8c | 2019-11-20 11:18:52 -0800 | [diff] [blame] | 147 | CalcEntryCRC = crc32(b''.join(struct.pack("B", x) for x in PartEntry)) |
T Michael Turney | 101098c | 2018-05-01 15:59:37 -0700 | [diff] [blame] | 148 | |
| 149 | GPTBlobBuffer[i] = CalcEntryCRC & 0xFF |
| 150 | GPTBlobBuffer[i+1] = (CalcEntryCRC>>8) & 0xFF |
| 151 | GPTBlobBuffer[i+2] = (CalcEntryCRC>>16) & 0xFF |
| 152 | GPTBlobBuffer[i+3] = (CalcEntryCRC>>24) & 0xFF |
| 153 | i += 4 |
| 154 | |
| 155 | # CRC of Partition Table Header |
| 156 | GPTHeader = GPTBlobBuffer[options.sector_size:options.sector_size + 92] |
Douglas Anderson | 1bdfe8c | 2019-11-20 11:18:52 -0800 | [diff] [blame] | 157 | CalcEntryCRC = crc32(b''.join(struct.pack("B", x) for x in GPTHeader)) |
T Michael Turney | 101098c | 2018-05-01 15:59:37 -0700 | [diff] [blame] | 158 | i = options.sector_size + 16 |
| 159 | |
| 160 | GPTBlobBuffer[i] = CalcEntryCRC & 0xFF |
| 161 | GPTBlobBuffer[i+1] = (CalcEntryCRC>>8) & 0xFF |
| 162 | GPTBlobBuffer[i+2] = (CalcEntryCRC>>16) & 0xFF |
| 163 | GPTBlobBuffer[i+3] = (CalcEntryCRC>>24) & 0xFF |
| 164 | |
| 165 | return i |
| 166 | |
| 167 | |
| 168 | if __name__ == '__main__': |
| 169 | usage = 'usage: %prog [OPTIONS] INFILE OUTFILE\n\n' + \ |
| 170 | 'Packages IMAGE in a GPT format.' |
| 171 | parser = OptionParser(usage) |
| 172 | parser.add_option('-s', type="int", dest='sector_size', default=4096, |
| 173 | help='Sector size in bytes [Default:4096(4KB)]', |
| 174 | metavar='SIZE') |
| 175 | |
| 176 | (options, args) = parser.parse_args() |
| 177 | if len(args) != 2: |
| 178 | print("Invalid arguments! Exiting...\n") |
| 179 | parser.print_help() |
| 180 | sys.exit(1) |
| 181 | |
| 182 | if options.sector_size != 4096 and options.sector_size != 512: |
| 183 | print("Invalid Sector Size") |
| 184 | sys.exit(1) |
| 185 | |
| 186 | options.inputfile = args[0] |
| 187 | options.outputfile = args[1] |
| 188 | |
Douglas Anderson | 1bdfe8c | 2019-11-20 11:18:52 -0800 | [diff] [blame] | 189 | with open(options.inputfile, 'rb+') as fin: |
T Michael Turney | 101098c | 2018-05-01 15:59:37 -0700 | [diff] [blame] | 190 | bb_buffer = fin.read() |
| 191 | |
| 192 | # Round up to next sector if bootblock size not evenly divisible |
Douglas Anderson | 1bdfe8c | 2019-11-20 11:18:52 -0800 | [diff] [blame] | 193 | options.end_lba = ((len(bb_buffer) + options.sector_size - 1) // |
T Michael Turney | 101098c | 2018-05-01 15:59:37 -0700 | [diff] [blame] | 194 | options.sector_size) |
| 195 | # Add 3 sectors for MBR, GPT header and GPT partition entry |
| 196 | options.end_lba += 3 |
| 197 | # Subtract one because this is last usable LBA, not amount of LBAs |
| 198 | options.end_lba -= 1 |
| 199 | |
| 200 | GPTBlobBuffer = [0] * (options.sector_size*3) #Size of MBR+GPT+PART_ENTRY |
| 201 | |
| 202 | UpdateMBR(options, GPTBlobBuffer) |
| 203 | |
| 204 | UpdatePartitionEntry(options, GPTBlobBuffer) |
| 205 | |
| 206 | UpdateGPTHeader(options, GPTBlobBuffer) |
| 207 | |
| 208 | with open(options.outputfile, 'wb') as fout: |
| 209 | for b in GPTBlobBuffer: |
| 210 | fout.write(struct.pack("B", b)) |
| 211 | fout.write(bb_buffer) |