Dump MMC via UBoot

mmc_dump.py

import os.path
import re
import sys
import struct
import serial
from tqdm import tqdm
import re

#   1.8192      .32768     .f4debf7b-01.0c
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#   2.40960     .655360    .f4debf7b-02.83
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#   3.696320    .655360    .f4debf7b-03.83
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#   4.1351680   .6381568   .f4debf7b-04.83
PART_R = re.compile(r'[ \t]+(\d+)[ \t]+(\d+)[ \t]+(\d+)[ \t]+([0-9a-f\-]+)[ \t]+([0-9a-f]+)')
DIR_R = re.compile(r'^<DIR>[ \t]+(\d+)[ \t]+(.+)$')
FILE_R = re.compile(r'^[ \t]+(\d+)[ \t]+(.+)$')
SYM_R = re.compile(r'^<SYM>[ \t]+(\d+)[ \t]+(.+)$')
FILE_GOOD_R = re.compile(r'(\d+) bytes read in .+$')


def exec_cmd(s, cmd):
    # print('executing %s' % cmd.decode())
    s.write(b'%s\n' % cmd)
    lines = []

    line = ''
    while True:
        b = s.read()

        if b in [b'\n', b'\r']:
            line = line.rstrip('\r\n')
            if len(line):
                lines.append(line)
            line = ''
            continue
        elif b == b'' and line.startswith('=> '):
            break

        line += b.decode('utf-8')

    return lines


def read_part(s, part):
    start, count = part['start'], part['count']

    res = exec_cmd(s, b'mmc read 10000000 %x %x' % (start, count))
    print(res)


def dump_part(s, part):
    size = 770  # 0x200 * part['count']

    off = 0
    bs = 0x1000
    # with open('dump_part_%d.bin' % part['index'], 'wb') as w:
    with open('shadow.bin', 'wb') as w:
        with tqdm(total=size) as pb:
            while size > 0:
                lines = exec_cmd(s, b'md.b %x %x' % (0x10000000 + off, min(bs, size)))[1:]
                for line in lines:
                    data, _ = line.split("    ", maxsplit=1)
                    _, strdata = data.split(maxsplit=1)
                    # addr = int.from_bytes(bytes.fromhex(straddr[:-1]), byteorder='big')
                    data = bytes.fromhex(strdata)
                    pb.update(0x10)
                    w.write(data)
                    size -= 0x10
                off += bs


def parse_hex_lines(lines, max_size):
    res = bytearray()
    for line in lines:
        data, _ = line.split("    ", maxsplit=1)
        _, strdata = data.split(maxsplit=1)
        data = bytes.fromhex(strdata)
        res.extend(data)

    return bytes(res)[:max_size]



def dump_file(s, path, size):
    w_path = '/'.join(['./', path])

    if size == 0:
        with open(w_path, 'wb') as w:
            pass
        return

    res = exec_cmd(s, b'ext2load mmc 1:2 10000000 %s' % path.encode())

    m = FILE_GOOD_R.match(res[1])
    real_sz = -1

    if m is not None:
        real_sz = m.group(1)

    assert real_sz != -1

    off = 0
    bs = min(size, 0x1000)

    with open(w_path, 'wb') as w:
        with tqdm(total=size) as pb:
            lines = exec_cmd(s, b'md.b %x %x' % (0x10000000 + off, bs))[1:]

            buf = parse_hex_lines(lines, bs)
            w.write(buf)
            pb.update(bs)
            size -= bs

            while size > 0:
                lines = exec_cmd(s, b'\n')

                blk = min(size, bs)
                buf = parse_hex_lines(lines, blk)
                w.write(buf)
                pb.update(blk)
                size -= blk


def dump_mmc_1_2(s, root='./', level=0):
    os.makedirs(root, exist_ok=True)

    res = exec_cmd(s, b'ext2ls mmc 1:2 %s' % root.encode())
    res = res[1:]

    dirs = []
    for line in res:
        m = DIR_R.match(line)

        if not m:
            m = SYM_R.match(line)

            if not m:
                m = FILE_R.match(line)

                if not m:
                    continue

                # do file
                size = int(m.group(1))
                name = m.group(2)
                print('%s%s %d' % (' ' * level, name, size))
                dump_file(s, '/'.join([root, name]), size)
                continue


            # do sym
            size = int(m.group(1))
            name = m.group(2)
            print('%s<%s> %d' % (' ' * level, name, size))
            dump_file(s, '/'.join([root, name]), 0)
            continue

        # do dir
        name = m.group(2)

        if name not in ['.', '..']:
            print('%s[%s]' % (' ' * level, name))
            dump_mmc_1_2(s, '/'.join([root, name]), level+1)
        # return sub_dirs


def main():
    s = serial.Serial('COM15', 115200, timeout=0.001)
    # s = serial.Serial('/dev/ttyUSB0', 115200, timeout=0.001)
    os.sep = '/'
    dump_mmc_1_2(s)
    # dump_part(s, '1')
    exit()
    res = exec_cmd(s, b'mmc part')

    parts = []
    for line in res:
        m = PART_R.match(line)

        if not m:
            continue

        part = {
            'index': int(m.group(1)),
            'start': int(m.group(2)),
            'count': int(m.group(3)),
            'uuid': m.group(4),
            'type': int(m.group(5), 16)
        }
        parts.append(part)

    read_part(s, parts[0])
    dump_part(s, parts[0])

    s.close()


if __name__ == '__main__':
    main()