Huawei Bootloader packed image format: C# parsing library

Format of bootloader-*.img files found in factory images of certain Android devices from Huawei:

All image versions can be found in factory images at https://developers.google.com/android/images for the specific device. To avoid having to download an entire ZIP archive when you only need one file from it, install remotezip and use its command line tool to list members in the archive and then to download only the file you want.

File extension

img

KS implementation details

License: CC0-1.0

This page hosts a formal specification of Huawei Bootloader packed image format using Kaitai Struct. This specification can be automatically translated into a variety of programming languages to get a parsing library.

Usage

Runtime library

All parsing code for C# generated by Kaitai Struct depends on the C# runtime library. You have to install it before you can parse data.

The C# runtime library is available in the NuGet Gallery. Installation instructions can also be found there.

Code

Parse a local file and get structure in memory:

var data = AndroidBootldrHuawei.FromFile("path/to/local/file.img");

Or parse structure from a byte array:

byte[] someArray = new byte[] { ... };
var data = new AndroidBootldrHuawei(new KaitaiStream(someArray));

After that, one can get various attributes from the structure by accessing properties like:

data.MetaHeader // => get meta header

C# source code to parse Huawei Bootloader packed image format

AndroidBootldrHuawei.cs

// This is a generated file! Please edit source .ksy file and use kaitai-struct-compiler to rebuild

using System.Collections.Generic;

namespace Kaitai
{

    /// <summary>
    /// Format of `bootloader-*.img` files found in factory images of certain Android devices from Huawei:
    /// 
    /// * Nexus 6P &quot;angler&quot;: [sample][sample-angler] ([other samples][others-angler]),
    ///   [releasetools.py](https://android.googlesource.com/device/huawei/angler/+/cf92cd8/releasetools.py#29)
    /// 
    /// [sample-angler]: https://androidfilehost.com/?fid=11410963190603870158 &quot;bootloader-angler-angler-03.84.img&quot;
    /// [others-angler]: https://androidfilehost.com/?w=search&amp;s=bootloader-angler&amp;type=files
    /// 
    /// All image versions can be found in factory images at
    /// &lt;https://developers.google.com/android/images&gt; for the specific device. To
    /// avoid having to download an entire ZIP archive when you only need one file
    /// from it, install [remotezip](https://github.com/gtsystem/python-remotezip) and
    /// use its [command line
    /// tool](https://github.com/gtsystem/python-remotezip#command-line-tool) to list
    /// members in the archive and then to download only the file you want.
    /// </summary>
    /// <remarks>
    /// Reference: <a href="https://android.googlesource.com/device/huawei/angler/+/673cfb9/releasetools.py">Source</a>
    /// </remarks>
    /// <remarks>
    /// Reference: <a href="https://source.codeaurora.org/quic/la/device/qcom/common/tree/meta_image/meta_format.h?h=LA.UM.6.1.1&amp;id=a68d284aee85">Source</a>
    /// </remarks>
    /// <remarks>
    /// Reference: <a href="https://source.codeaurora.org/quic/la/device/qcom/common/tree/meta_image/meta_image.c?h=LA.UM.6.1.1&amp;id=a68d284aee85">Source</a>
    /// </remarks>
    public partial class AndroidBootldrHuawei : KaitaiStruct
    {
        public static AndroidBootldrHuawei FromFile(string fileName)
        {
            return new AndroidBootldrHuawei(new KaitaiStream(fileName));
        }

        public AndroidBootldrHuawei(KaitaiStream p__io, KaitaiStruct p__parent = null, AndroidBootldrHuawei p__root = null) : base(p__io)
        {
            m_parent = p__parent;
            m_root = p__root ?? this;
            _read();
        }
        private void _read()
        {
            _metaHeader = new MetaHdr(m_io, this, m_root);
            _headerExt = m_io.ReadBytes((MetaHeader.LenMetaHeader - 76));
            __raw_imageHeader = m_io.ReadBytes(MetaHeader.LenImageHeader);
            var io___raw_imageHeader = new KaitaiStream(__raw_imageHeader);
            _imageHeader = new ImageHdr(io___raw_imageHeader, this, m_root);
        }
        public partial class MetaHdr : KaitaiStruct
        {
            public static MetaHdr FromFile(string fileName)
            {
                return new MetaHdr(new KaitaiStream(fileName));
            }

            public MetaHdr(KaitaiStream p__io, AndroidBootldrHuawei p__parent = null, AndroidBootldrHuawei p__root = null) : base(p__io)
            {
                m_parent = p__parent;
                m_root = p__root;
                _read();
            }
            private void _read()
            {
                _magic = m_io.ReadBytes(4);
                if (!((KaitaiStream.ByteArrayCompare(Magic, new byte[] { 60, 214, 26, 206 }) == 0)))
                {
                    throw new ValidationNotEqualError(new byte[] { 60, 214, 26, 206 }, Magic, M_Io, "/types/meta_hdr/seq/0");
                }
                _version = new Version(m_io, this, m_root);
                _imageVersion = System.Text.Encoding.GetEncoding("ASCII").GetString(KaitaiStream.BytesTerminate(m_io.ReadBytes(64), 0, false));
                _lenMetaHeader = m_io.ReadU2le();
                _lenImageHeader = m_io.ReadU2le();
            }
            private byte[] _magic;
            private Version _version;
            private string _imageVersion;
            private ushort _lenMetaHeader;
            private ushort _lenImageHeader;
            private AndroidBootldrHuawei m_root;
            private AndroidBootldrHuawei m_parent;
            public byte[] Magic { get { return _magic; } }
            public Version Version { get { return _version; } }
            public string ImageVersion { get { return _imageVersion; } }
            public ushort LenMetaHeader { get { return _lenMetaHeader; } }
            public ushort LenImageHeader { get { return _lenImageHeader; } }
            public AndroidBootldrHuawei M_Root { get { return m_root; } }
            public AndroidBootldrHuawei M_Parent { get { return m_parent; } }
        }
        public partial class Version : KaitaiStruct
        {
            public static Version FromFile(string fileName)
            {
                return new Version(new KaitaiStream(fileName));
            }

            public Version(KaitaiStream p__io, AndroidBootldrHuawei.MetaHdr p__parent = null, AndroidBootldrHuawei p__root = null) : base(p__io)
            {
                m_parent = p__parent;
                m_root = p__root;
                _read();
            }
            private void _read()
            {
                _major = m_io.ReadU2le();
                _minor = m_io.ReadU2le();
            }
            private ushort _major;
            private ushort _minor;
            private AndroidBootldrHuawei m_root;
            private AndroidBootldrHuawei.MetaHdr m_parent;
            public ushort Major { get { return _major; } }
            public ushort Minor { get { return _minor; } }
            public AndroidBootldrHuawei M_Root { get { return m_root; } }
            public AndroidBootldrHuawei.MetaHdr M_Parent { get { return m_parent; } }
        }
        public partial class ImageHdr : KaitaiStruct
        {
            public static ImageHdr FromFile(string fileName)
            {
                return new ImageHdr(new KaitaiStream(fileName));
            }

            public ImageHdr(KaitaiStream p__io, AndroidBootldrHuawei p__parent = null, AndroidBootldrHuawei p__root = null) : base(p__io)
            {
                m_parent = p__parent;
                m_root = p__root;
                _read();
            }
            private void _read()
            {
                _entries = new List<ImageHdrEntry>();
                {
                    var i = 0;
                    while (!m_io.IsEof) {
                        _entries.Add(new ImageHdrEntry(m_io, this, m_root));
                        i++;
                    }
                }
            }
            private List<ImageHdrEntry> _entries;
            private AndroidBootldrHuawei m_root;
            private AndroidBootldrHuawei m_parent;

            /// <summary>
            /// The C generator program defines `img_header` as a [fixed size
            /// array](https://source.codeaurora.org/quic/la/device/qcom/common/tree/meta_image/meta_image.c?h=LA.UM.6.1.1&amp;id=a68d284aee85#n42)
            /// of `img_header_entry_t` structs with length `MAX_IMAGES` (which is
            /// defined as `16`).
            /// 
            /// This means that technically there will always be 16 `image_hdr`
            /// entries, the first *n* entries being used (filled with real values)
            /// and the rest left unused with all bytes zero.
            /// 
            /// To check if an entry is used, use the `is_used` attribute.
            /// </summary>
            public List<ImageHdrEntry> Entries { get { return _entries; } }
            public AndroidBootldrHuawei M_Root { get { return m_root; } }
            public AndroidBootldrHuawei M_Parent { get { return m_parent; } }
        }
        public partial class ImageHdrEntry : KaitaiStruct
        {
            public static ImageHdrEntry FromFile(string fileName)
            {
                return new ImageHdrEntry(new KaitaiStream(fileName));
            }

            public ImageHdrEntry(KaitaiStream p__io, AndroidBootldrHuawei.ImageHdr p__parent = null, AndroidBootldrHuawei p__root = null) : base(p__io)
            {
                m_parent = p__parent;
                m_root = p__root;
                f_isUsed = false;
                f_body = false;
                _read();
            }
            private void _read()
            {
                _name = System.Text.Encoding.GetEncoding("ASCII").GetString(KaitaiStream.BytesTerminate(m_io.ReadBytes(72), 0, false));
                _ofsBody = m_io.ReadU4le();
                _lenBody = m_io.ReadU4le();
            }
            private bool f_isUsed;
            private bool _isUsed;

            /// <remarks>
            /// Reference: <a href="https://source.codeaurora.org/quic/la/device/qcom/common/tree/meta_image/meta_image.c?h=LA.UM.6.1.1&amp;id=a68d284aee85#n119">Source</a>
            /// </remarks>
            public bool IsUsed
            {
                get
                {
                    if (f_isUsed)
                        return _isUsed;
                    _isUsed = (bool) ( ((OfsBody != 0) && (LenBody != 0)) );
                    f_isUsed = true;
                    return _isUsed;
                }
            }
            private bool f_body;
            private byte[] _body;
            public byte[] Body
            {
                get
                {
                    if (f_body)
                        return _body;
                    if (IsUsed) {
                        KaitaiStream io = M_Root.M_Io;
                        long _pos = io.Pos;
                        io.Seek(OfsBody);
                        _body = io.ReadBytes(LenBody);
                        io.Seek(_pos);
                        f_body = true;
                    }
                    return _body;
                }
            }
            private string _name;
            private uint _ofsBody;
            private uint _lenBody;
            private AndroidBootldrHuawei m_root;
            private AndroidBootldrHuawei.ImageHdr m_parent;

            /// <summary>
            /// partition name
            /// </summary>
            public string Name { get { return _name; } }
            public uint OfsBody { get { return _ofsBody; } }
            public uint LenBody { get { return _lenBody; } }
            public AndroidBootldrHuawei M_Root { get { return m_root; } }
            public AndroidBootldrHuawei.ImageHdr M_Parent { get { return m_parent; } }
        }
        private MetaHdr _metaHeader;
        private byte[] _headerExt;
        private ImageHdr _imageHeader;
        private AndroidBootldrHuawei m_root;
        private KaitaiStruct m_parent;
        private byte[] __raw_imageHeader;
        public MetaHdr MetaHeader { get { return _metaHeader; } }
        public byte[] HeaderExt { get { return _headerExt; } }
        public ImageHdr ImageHeader { get { return _imageHeader; } }
        public AndroidBootldrHuawei M_Root { get { return m_root; } }
        public KaitaiStruct M_Parent { get { return m_parent; } }
        public byte[] M_RawImageHeader { get { return __raw_imageHeader; } }
    }
}