duplicati/Duplicati/Library/Backend/SMB/SMBBackend.cs
Kenneth Skovhede 012aeed7de Add dynamic streaming toggle
This PR adds a dynamic property so a backend can signal if it supports streaming, based on the settings.

This is currently used for the File backend, so that toggling `--use-move-for-put` will disable streaming on the backend instead of relying on the `--disable-streaming-transfers` flag.
2025-11-03 12:48:37 +01:00

350 lines
No EOL
16 KiB
C#

// Copyright (C) 2025, The Duplicati Team
// https://duplicati.com, hello@duplicati.com
//
// Permission is hereby granted, free of charge, to any person obtaining a
// copy of this software and associated documentation files (the "Software"),
// to deal in the Software without restriction, including without limitation
// the rights to use, copy, modify, merge, publish, distribute, sublicense,
// and/or sell copies of the Software, and to permit persons to whom the
// Software is furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
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using Duplicati.Library.Interface;
using Duplicati.Library.Backend.SMB;
using Duplicati.Library.Backend.SMB.Model;
using SMBLibrary;
using Duplicati.Library.SourceProvider;
using System.Runtime.CompilerServices;
using Duplicati.Library.Common.IO;
using Duplicati.Library.Utility.Options;
using Duplicati.Library.Utility;
namespace Duplicati.Library.Backend;
/// <summary>
/// Native CIFS/SMB Backend implementation
/// </summary>
public class SMBBackend : IStreamingBackend, IFolderEnabledBackend
{
/// <inheritdoc/>
public virtual string ProtocolKey => "smb";
/// <inheritdoc/>
public virtual string DisplayName => Strings.SMBBackend.DisplayName;
/// <inheritdoc/>
public virtual string Description => Strings.SMBBackend.Description;
/// <inheritdoc/>
public virtual bool SupportsStreaming => true;
/// <summary>
/// Hostname only (no ports or paths) to be used on DNS resolutions.
/// </summary>
private string _DnsName;
/// <summary>
/// Path separators (both Windows \ and unix /) to be used in path manipulation
/// </summary>
private static readonly char[] PATH_SEPARATORS = ['/', '\\'];
/// <summary>
/// Cache of parsed connection parameters
/// </summary>
private readonly SMBConnectionParameters _connectionParameters;
/// <summary>
/// Timeout options to be used in the backend
/// </summary>
private readonly TimeoutOptionsHelper.Timeouts _timeouts;
/// <summary>
/// Shared connection between all methods to avoid re-authentication
/// </summary>
private SMBShareConnection? _sharedConnection;
/// <summary>
/// Read buffer size for SMB operations (will be capped automatically by SMB negotiated values)
/// </summary>
private const string READ_BUFFER_SIZE_OPTION = "read-buffer-size";
/// <summary>
/// Write buffer size for SMB operations (will be capped automatically by SMB negotiated values)
/// </summary>
private const string WRITE_BUFFER_SIZE_OPTION = "write-buffer-size";
/// <summary>
/// Backend option for controlling the transport (directtcp or netbios)
/// </summary>
private const string TRANSPORT_OPTION = "transport";
/// <summary>
/// Domain (complementary part of authentication) option
/// </summary>
private const string AUTH_DOMAIN_OPTION = "auth-domain";
/// <summary>
/// Defines the default transport to be used in CIFS connection
/// </summary>
private const string DEFAULT_TRANSPORT = "directtcp";
/// <summary>
/// Mapping of transport string to SMBTransportType enum to be used in parsing the option string
/// </summary>
private readonly Dictionary<string, SMBTransportType> _transportMap = new()
{
["directtcp"] = SMBTransportType.DirectTCPTransport,
["netbios"] = SMBTransportType.NetBiosOverTCP
};
/// <summary>
/// Empty constructor is required for the backend to be loaded by the backend factory
/// </summary>
public SMBBackend()
{
_DnsName = null!;
_connectionParameters = null!;
_timeouts = null!;
}
/// <summary>
/// Actual constructor for the backend that accepts the url and options
/// </summary>
/// <param name="url">URL in Duplicati Uri format</param>
/// <param name="options">options to be used in the backend</param>
public SMBBackend(string url, Dictionary<string, string?> options)
{
if (string.IsNullOrEmpty(url))
throw new ArgumentNullException(nameof(url));
if (options == null)
throw new ArgumentNullException(nameof(options));
var uri = new Utility.Uri(url);
uri.RequireHost();
_DnsName = uri.Host ?? "";
var input = uri.Path.TrimEnd('/');
var slashIndex = input.IndexOf('/'); // Find first slash to separate server and share if present.
var auth = AuthOptionsHelper.Parse(options, uri);
var authDomain = options.GetValueOrDefault(AUTH_DOMAIN_OPTION);
var transport = options.GetValueOrDefault(TRANSPORT_OPTION);
int? readBufferSize = null, writeBufferSize = null;
var readBufferSizeConfig = options.GetValueOrDefault(READ_BUFFER_SIZE_OPTION);
if (!string.IsNullOrWhiteSpace(readBufferSizeConfig))
readBufferSize = int.TryParse(readBufferSizeConfig, out int value) ? value : null;
var writeBufferSizeConfig = options.GetValueOrDefault(WRITE_BUFFER_SIZE_OPTION);
if (!string.IsNullOrWhiteSpace(writeBufferSizeConfig))
writeBufferSize = int.TryParse(writeBufferSizeConfig, out int value) ? value : null;
// Normalize to 10KB minimum buffers size
readBufferSize = readBufferSize < 1024 * 10 ? null : readBufferSize;
writeBufferSize = writeBufferSize < 1024 * 10 ? null : writeBufferSize;
var transportType = _transportMap.TryGetValue(
string.IsNullOrEmpty(transport) ? DEFAULT_TRANSPORT : transport.ToLower(),
out SMBTransportType type)
? type
: throw new UserInformationException($"Transport must be one of: {string.Join(", ", _transportMap.Keys)}", "CIFSConfig");
_timeouts = TimeoutOptionsHelper.Parse(options);
_connectionParameters = new SMBConnectionParameters(
_DnsName,
transportType,
slashIndex >= 0 ? input[..slashIndex] : input,
slashIndex >= 0 ? input[(slashIndex + 1)..] : "",
authDomain,
auth.Username,
auth.Password,
readBufferSize,
writeBufferSize
);
}
/// <summary>
/// Implementation of interface property to return supported command parameters
/// </summary>
public IList<ICommandLineArgument> SupportedCommands =>
[
.. AuthOptionsHelper.GetOptions(),
new CommandLineArgument(AUTH_DOMAIN_OPTION, CommandLineArgument.ArgumentType.String, Strings.SMBBackend.DescriptionAuthDomainShort, Strings.SMBBackend.DescriptionAuthDomainLong),
new CommandLineArgument(TRANSPORT_OPTION, CommandLineArgument.ArgumentType.Enumeration, Strings.Options.TransportShort, Strings.Options.TransportLong, DEFAULT_TRANSPORT, null, _transportMap.Keys.ToArray()),
new CommandLineArgument(READ_BUFFER_SIZE_OPTION, CommandLineArgument.ArgumentType.String, Strings.Options.DescriptionReadBufferSizeShort, Strings.Options.DescriptionReadBufferSizeLong),
new CommandLineArgument(WRITE_BUFFER_SIZE_OPTION, CommandLineArgument.ArgumentType.String, Strings.Options.DescriptionWriteBufferSizeShort, Strings.Options.DescriptionWriteBufferSizeLong),
.. TimeoutOptionsHelper.GetOptions()
];
/// <summary>
/// Implementation of interface method for listing remote folder contents
/// </summary>
/// <returns>List of IFileEntry with directory listing result</returns>
public async IAsyncEnumerable<IFileEntry> ListAsync([EnumeratorCancellation] CancellationToken cancellationToken)
{
var con = await GetConnectionAsync(cancellationToken).ConfigureAwait(false);
foreach (var v in await con.ListAsync(_connectionParameters.Path, cancellationToken).ConfigureAwait(false))
yield return v;
}
/// <summary>
/// Upload files to remote location
/// </summary>
/// <param name="remotename">Filename at remote location</param>
/// <param name="localname">Filename to read from</param>
/// <param name="cancellationToken">CancellationToken that is combined with internal timeout token</param>
/// <exception cref="FileMissingException">FileMissingException when file is not found</exception>
/// <exception cref="Exception">Exceptions arising from either code execution</exception>
public async Task PutAsync(string remotename, string localname, CancellationToken cancellationToken)
{
await using var fs = File.Open(localname,
FileMode.Open, FileAccess.Read, FileShare.Read);
await PutAsync(remotename, fs, cancellationToken).ConfigureAwait(false);
}
/// <summary>
/// Upload files to remote location
/// </summary>
/// <param name="remotename">Filename at remote location</param>
/// <param name="input">Stream to read from</param>
/// <param name="cancellationToken">CancellationToken that is combined with internal timeout token</param>
/// <exception cref="FileMissingException">FileMissingException when file is not found</exception>
/// <exception cref="Exception">Exceptions arising from either code execution</exception>
public async Task PutAsync(string remotename, Stream input, CancellationToken cancellationToken)
{
var con = await GetConnectionAsync(cancellationToken).ConfigureAwait(false);
await con.PutAsync(remotename, input, cancellationToken).ConfigureAwait(false);
}
/// <summary>
/// Download files from remote
/// </summary>
/// <param name="remotename">Filename at remote location</param>
/// <param name="localname">Local filename to write to</param>
/// <param name="cancellationToken">CancellationToken that is combined with internal timeout token</param>
/// <exception cref="FileMissingException">FileMissingException when file is not found</exception>
/// <exception cref="Exception">Exceptions arising from either code execution or FileMissingException</exception>
public async Task GetAsync(string remotename, string localname, CancellationToken cancellationToken)
{
await using var fs = File.Open(localname,
FileMode.Create, FileAccess.Write,
FileShare.None);
await GetAsync(remotename, fs, cancellationToken).ConfigureAwait(false);
}
/// <summary>
/// Download files from remote
/// </summary>
/// <param name="remotename">Filename at remote location</param>
/// <param name="output">Destination stream to write to</param>
/// <param name="cancellationToken">CancellationToken that is combined with internal timeout token</param>
/// <exception cref="FileMissingException">FileMissingException when file is not found</exception>
/// <exception cref="Exception">Exceptions arising from either code execution or FileMissingException</exception>
public async Task GetAsync(string remotename, Stream output, CancellationToken cancellationToken)
{
var con = await GetConnectionAsync(cancellationToken).ConfigureAwait(false);
await con.GetAsync(remotename, output, cancellationToken).ConfigureAwait(false);
}
/// <summary>
/// Delete remote file if it exists, if not, throws FileMissingException
/// </summary>
/// <param name="remotename">filename to be deleted on the remote</param>
/// <param name="cancellationToken">CancellationToken that is combined with internal timeout token</param>
/// <returns></returns>
/// <exception cref="FileMissingException">FileMissingException when file is not found</exception>
/// <exception cref="Exception">Exceptions arising from either code execution or business logic errors</exception>
public async Task DeleteAsync(string remotename, CancellationToken cancellationToken)
{
var con = await GetConnectionAsync(cancellationToken).ConfigureAwait(false);
await con.DeleteAsync(remotename, cancellationToken).ConfigureAwait(false);
}
/// <summary>
/// Implementation of interface function to return hosnames used by the backend
/// </summary>
/// <param name="cancellationToken">CancellationToken, in this call not used.</param>
/// <returns></returns>
public Task<string[]> GetDNSNamesAsync(CancellationToken cancellationToken) =>
Task.FromResult(new[] { _DnsName ?? string.Empty });
/// <summary>
/// Tests backend connectivity by verifying the configured path exists
/// </summary>
/// <param name="cancellationToken">The cancellation token (not used)</param>
/// <exception cref="FolderMissingException">Thrown when configured path does not exist</exception>
public Task TestAsync(CancellationToken cancellationToken)
=> this.TestReadWritePermissionsAsync(cancellationToken);
/// <summary>
/// Creates the configured remote folder path if it doesn't exist
/// </summary>
/// <param name="cancellationToken">CancellationToken that will be combined with internal timeout token</param>
/// <returns>Task representing the asynchronous operation</returns>
/// <exception cref="Exception">Thrown when folder creation fails</exception>
public async Task CreateFolderAsync(CancellationToken cancellationToken)
{
var pathParts = _connectionParameters.Path?
.Split(PATH_SEPARATORS, StringSplitOptions.RemoveEmptyEntries);
if (pathParts == null || pathParts.Length == 0)
return;
var con = await GetConnectionAsync(cancellationToken).ConfigureAwait(false);
await con.CreateFolderAsync(_connectionParameters.Path ?? "", cancellationToken)
.ConfigureAwait(false);
}
/// <summary>
/// Gets or creates a shared SMB connection
/// </summary>
/// <returns>An SMB connection that can be used for file operations</returns>
private async Task<SMBShareConnection> GetConnectionAsync(CancellationToken cancellationToken)
=> _sharedConnection ??= await SMBShareConnection.CreateAsync(_connectionParameters, _timeouts, cancellationToken).ConfigureAwait(false);
/// <summary>
/// Implementation of Dispose pattern enforced by interface
/// </summary>
public void Dispose()
{
try
{
_sharedConnection?.Dispose();
}
catch (Exception ex)
{
// Log the exception but don't rethrow since we're in Dispose
System.Diagnostics.Debug.WriteLine($"Error disposing CIFS connection: {ex.Message}");
}
}
/// <inheritdoc/>
public async IAsyncEnumerable<IFileEntry> ListAsync(string? path, [EnumeratorCancellation] CancellationToken cancellationToken)
{
var sourcePath = _connectionParameters.Path;
if (!string.IsNullOrWhiteSpace(sourcePath))
sourcePath = Util.AppendDirSeparator(sourcePath, "/");
var con = await GetConnectionAsync(cancellationToken).ConfigureAwait(false);
foreach (var v in await con.ListAsync(sourcePath + BackendSourceFileEntry.NormalizePathTo(path, '/'), cancellationToken).ConfigureAwait(false))
if (v.Name != "." && v.Name != "..")
yield return v;
}
/// <inheritdoc/>
public Task<IFileEntry?> GetEntryAsync(string path, CancellationToken cancellationToken)
=> Task.FromResult<IFileEntry?>(null);
}