mirror of
https://github.com/aaru-dps/Aaru.git
synced 2026-04-05 21:44:17 +00:00
286 lines
11 KiB
C#
286 lines
11 KiB
C#
// /***************************************************************************
|
|
// Aaru Data Preservation Suite
|
|
// ----------------------------------------------------------------------------
|
|
//
|
|
// Filename : AixMinidisk.cs
|
|
// Author(s) : Natalia Portillo <claunia@claunia.com>
|
|
//
|
|
// Component : Partitioning scheme plugins.
|
|
//
|
|
// --[ Description ] ----------------------------------------------------------
|
|
//
|
|
// Manages AIX minidisk partitions (VTOC).
|
|
//
|
|
// --[ License ] --------------------------------------------------------------
|
|
//
|
|
// This library is free software; you can redistribute it and/or modify
|
|
// it under the terms of the GNU Lesser General Public License as
|
|
// published by the Free Software Foundation; either version 2.1 of the
|
|
// License, or (at your option) any later version.
|
|
//
|
|
// This library is distributed in the hope that it will be useful, but
|
|
// WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
|
// Lesser General Public License for more details.
|
|
//
|
|
// You should have received a copy of the GNU Lesser General Public
|
|
// License along with this library; if not, see <http://www.gnu.org/licenses/>.
|
|
//
|
|
// ----------------------------------------------------------------------------
|
|
// Copyright © 2011-2026 Natalia Portillo
|
|
// ****************************************************************************/
|
|
|
|
using System;
|
|
using System.Collections.Generic;
|
|
using System.Diagnostics.CodeAnalysis;
|
|
using System.Runtime.InteropServices;
|
|
using System.Text;
|
|
using Aaru.CommonTypes;
|
|
using Aaru.CommonTypes.Enums;
|
|
using Aaru.CommonTypes.Interfaces;
|
|
using Aaru.Logging;
|
|
using Marshal = Aaru.Helpers.Marshal;
|
|
|
|
namespace Aaru.Partitions;
|
|
|
|
/// <inheritdoc />
|
|
/// <summary>Implements decoding of the AIX minidisk (VTOC) partitioning scheme</summary>
|
|
[SuppressMessage("ReSharper", "InconsistentNaming")]
|
|
public sealed class AixMinidisk : IPartition
|
|
{
|
|
const string MODULE_NAME = "AIX minidisk plugin";
|
|
|
|
/// <summary>AIX VTOC magic string "VTOC"</summary>
|
|
const uint VTOC_MAGIC = 0x56544F43; // "VTOC" in ASCII
|
|
|
|
/// <summary>Block size for AIX minidisks</summary>
|
|
const int BLOCKSIZE = 512;
|
|
|
|
/// <summary>Maximum number of minidisks in VTOC</summary>
|
|
const int MAX_MINIDISKS = 32;
|
|
|
|
/// <inheritdoc />
|
|
public string Name => "AIX minidisk";
|
|
|
|
/// <inheritdoc />
|
|
public Guid Id => new("25ED1C9A-0FF0-49FC-9F43-34844B8309B8");
|
|
|
|
/// <inheritdoc />
|
|
public string Author => Authors.NATALIA_PORTILLO;
|
|
|
|
/// <inheritdoc />
|
|
public bool GetInformation(IMediaImage imagePlugin, out List<Partition> partitions, ulong sectorOffset)
|
|
{
|
|
partitions = [];
|
|
|
|
// VTOC is typically at sector 1 (after boot0)
|
|
// But we need to find the AIX partition first if coming from MBR
|
|
ulong vtocSector = sectorOffset + 1;
|
|
|
|
ErrorNumber errno = imagePlugin.ReadSector(vtocSector, false, out byte[] sector, out _);
|
|
|
|
if(errno != ErrorNumber.NoError || sector.Length < BLOCKSIZE)
|
|
{
|
|
AaruLogging.Debug(MODULE_NAME, "Error reading VTOC sector: {0}", errno);
|
|
|
|
return false;
|
|
}
|
|
|
|
// Check for VTOC magic
|
|
var magic = (uint)(sector[0] << 24 | sector[1] << 16 | sector[2] << 8 | sector[3]);
|
|
|
|
AaruLogging.Debug(MODULE_NAME, "VTOC magic = 0x{0:X8}, expected 0x{1:X8}", magic, VTOC_MAGIC);
|
|
|
|
if(magic != VTOC_MAGIC)
|
|
{
|
|
AaruLogging.Debug(MODULE_NAME, "VTOC magic not found at sector {0}", vtocSector);
|
|
|
|
return false;
|
|
}
|
|
|
|
Vtoc1 vtoc = Marshal.ByteArrayToStructureLittleEndian<Vtoc1>(sector);
|
|
|
|
AaruLogging.Debug(MODULE_NAME,
|
|
"vtoc.magic_string = \"{0}\"",
|
|
Encoding.ASCII.GetString(vtoc.magic_string).TrimEnd('\0'));
|
|
|
|
AaruLogging.Debug(MODULE_NAME, "vtoc.version = {0}", vtoc.version);
|
|
AaruLogging.Debug(MODULE_NAME, "vtoc.seq_num = {0}", vtoc.seq_num);
|
|
AaruLogging.Debug(MODULE_NAME, "vtoc.bootsize = {0}", vtoc.bootsize);
|
|
AaruLogging.Debug(MODULE_NAME, "vtoc.numbadblks = {0}", vtoc.numbadblks);
|
|
AaruLogging.Debug(MODULE_NAME, "vtoc.badblkoff = {0}", vtoc.badblkoff);
|
|
|
|
// Read VTOC2 and VTOC3 for mount string table
|
|
errno = imagePlugin.ReadSector(vtocSector + 1, false, out byte[] vtoc2Sector, out _);
|
|
|
|
if(errno != ErrorNumber.NoError)
|
|
{
|
|
AaruLogging.Debug(MODULE_NAME, "Error reading VTOC2 sector: {0}", errno);
|
|
|
|
return false;
|
|
}
|
|
|
|
errno = imagePlugin.ReadSector(vtocSector + 2, false, out byte[] vtoc3Sector, out _);
|
|
|
|
if(errno != ErrorNumber.NoError)
|
|
{
|
|
AaruLogging.Debug(MODULE_NAME, "Error reading VTOC3 sector: {0}", errno);
|
|
|
|
return false;
|
|
}
|
|
|
|
// Build the string table from VTOC2 and VTOC3
|
|
// VTOC2: byte 0 is seq_num, bytes 1-511 are first part of string table
|
|
// VTOC3: bytes 0-506 are second part, byte 507 is seq_num, bytes 508-511 are checksum
|
|
var stringTable = new byte[511 + 507]; // V2_STRTABLEN + V3_STRTABLEN
|
|
Array.Copy(vtoc2Sector, 1, stringTable, 0, 511);
|
|
Array.Copy(vtoc3Sector, 0, stringTable, 511, 507);
|
|
|
|
ulong counter = 0;
|
|
|
|
for(var i = 0; i < MAX_MINIDISKS; i++)
|
|
{
|
|
Minidisk md = vtoc.mini[i];
|
|
|
|
// Check for end marker
|
|
if(md.type == MD_END)
|
|
{
|
|
AaruLogging.Debug(MODULE_NAME, "End of minidisk table at entry {0}", i);
|
|
|
|
break;
|
|
}
|
|
|
|
AaruLogging.Debug(MODULE_NAME, "vtoc.mini[{0}].s_block = {1}", i, md.s_block);
|
|
AaruLogging.Debug(MODULE_NAME, "vtoc.mini[{0}].num_blks = {1}", i, md.num_blks);
|
|
AaruLogging.Debug(MODULE_NAME, "vtoc.mini[{0}].type = {1} ({2})", i, md.type, TypeToString(md.type));
|
|
AaruLogging.Debug(MODULE_NAME, "vtoc.mini[{0}].mdisk_id = {1}", i, md.mdisk_id);
|
|
AaruLogging.Debug(MODULE_NAME, "vtoc.mini[{0}].str_index = {1}", i, md.str_index);
|
|
|
|
// Skip entries with no blocks
|
|
if(md.num_blks == 0) continue;
|
|
|
|
// Skip reserved and bad block entries
|
|
if(md.type is MD_BAD_BLOCK or MD_UNALLOC) continue;
|
|
|
|
// Get mount point string from string table
|
|
var mountPoint = "";
|
|
|
|
if(md.str_index > 0 && md.str_index < stringTable.Length)
|
|
{
|
|
int strEnd = Array.IndexOf<byte>(stringTable, 0, md.str_index);
|
|
int strLen = strEnd >= 0 ? strEnd - md.str_index : stringTable.Length - md.str_index;
|
|
mountPoint = Encoding.ASCII.GetString(stringTable, md.str_index, strLen);
|
|
}
|
|
|
|
var part = new Partition
|
|
{
|
|
Start = md.s_block * BLOCKSIZE / imagePlugin.Info.SectorSize,
|
|
Offset = md.s_block * BLOCKSIZE,
|
|
Length = md.num_blks * BLOCKSIZE / imagePlugin.Info.SectorSize,
|
|
Size = md.num_blks * BLOCKSIZE,
|
|
Type = TypeToString(md.type),
|
|
Sequence = counter,
|
|
Scheme = Name,
|
|
Name = string.IsNullOrEmpty(mountPoint) ? $"hd{md.mdisk_id & 0x1F}" : mountPoint
|
|
};
|
|
|
|
AaruLogging.Debug(MODULE_NAME,
|
|
"Partition {0}: start={1}, length={2}, type={3}, name={4}",
|
|
counter,
|
|
part.Start,
|
|
part.Length,
|
|
part.Type,
|
|
part.Name);
|
|
|
|
partitions.Add(part);
|
|
counter++;
|
|
}
|
|
|
|
return partitions.Count > 0;
|
|
}
|
|
|
|
static string TypeToString(byte type) => type switch
|
|
{
|
|
MD_END => "End marker",
|
|
MD_PAGE => "AIX paging space",
|
|
MD_DUMP => "AIX dump space",
|
|
MD_UNALLOC => "Unallocated",
|
|
MD_AIX_BOOT => "AIX boot",
|
|
MD_AIX_NOBOOT => "AIX filesystem",
|
|
MD_BAD_BLOCK => "Bad block table",
|
|
_ => $"Unknown (0x{type:X2})"
|
|
};
|
|
|
|
#region Constants
|
|
|
|
/// <summary>End of VTOC table marker</summary>
|
|
const byte MD_END = 0;
|
|
|
|
/// <summary>Page space minidisk</summary>
|
|
const byte MD_PAGE = 1;
|
|
|
|
/// <summary>Dump space minidisk</summary>
|
|
const byte MD_DUMP = 2;
|
|
|
|
/// <summary>Free space for AIX</summary>
|
|
const byte MD_UNALLOC = 3;
|
|
|
|
/// <summary>AIX minidisk containing /unixtext</summary>
|
|
const byte MD_AIX_BOOT = 8;
|
|
|
|
/// <summary>Any other AIX minidisk</summary>
|
|
const byte MD_AIX_NOBOOT = 9;
|
|
|
|
/// <summary>Bad block table minidisk</summary>
|
|
const byte MD_BAD_BLOCK = 0x0E;
|
|
|
|
#endregion
|
|
|
|
#region Nested type: Minidisk
|
|
|
|
/// <summary>AIX minidisk entry structure</summary>
|
|
[StructLayout(LayoutKind.Sequential, Pack = 1)]
|
|
struct Minidisk
|
|
{
|
|
/// <summary>Starting block number</summary>
|
|
public readonly uint s_block;
|
|
/// <summary>Length of minidisk in blocks</summary>
|
|
public readonly uint num_blks;
|
|
/// <summary>Type of minidisk</summary>
|
|
public readonly byte type;
|
|
/// <summary>Minidisk ID number</summary>
|
|
public readonly byte mdisk_id;
|
|
/// <summary>Index into string table</summary>
|
|
public readonly ushort str_index;
|
|
}
|
|
|
|
#endregion
|
|
|
|
#region Nested type: Vtoc1
|
|
|
|
/// <summary>AIX VTOC sector 1 structure</summary>
|
|
[StructLayout(LayoutKind.Sequential, Pack = 1)]
|
|
struct Vtoc1
|
|
{
|
|
/// <summary>"VTOC" magic string</summary>
|
|
[MarshalAs(UnmanagedType.ByValArray, SizeConst = 4)]
|
|
public readonly byte[] magic_string;
|
|
/// <summary>Version number</summary>
|
|
public readonly byte version;
|
|
/// <summary>Sequence number (must match others)</summary>
|
|
public readonly byte seq_num;
|
|
/// <summary>Max length of boot 1 in disk blocks</summary>
|
|
public readonly ushort bootsize;
|
|
/// <summary>Number of bad blocks (ST506 only)</summary>
|
|
public readonly ushort numbadblks;
|
|
/// <summary>Offset within the bad block minidisk</summary>
|
|
public readonly ushort badblkoff;
|
|
/// <summary>Spare (to put mini[] on 8 byte boundary)</summary>
|
|
public readonly int vt_spare;
|
|
/// <summary>Minidisk entries</summary>
|
|
[MarshalAs(UnmanagedType.ByValArray, SizeConst = MAX_MINIDISKS)]
|
|
public readonly Minidisk[] mini;
|
|
}
|
|
|
|
#endregion
|
|
} |