{"id":353659,"date":"2024-08-27T10:00:12","date_gmt":"2024-08-27T10:00:12","guid":{"rendered":"https:\/\/www.ninjaone.com\/script-hub\/verification-du-hachage-des-fichiers-powershell\/"},"modified":"2024-10-13T19:08:45","modified_gmt":"2024-10-13T19:08:45","slug":"verification-du-hachage-des-fichiers-powershell","status":"publish","type":"script_hub","link":"https:\/\/www.ninjaone.com\/fr\/script-hub\/verification-du-hachage-des-fichiers-powershell\/","title":{"rendered":"Comment utiliser PowerShell pour la v\u00e9rification du hachage des fichiers pour la s\u00e9curit\u00e9 informatique ?"},"content":{"rendered":"

Dans le monde informatique actuel, il est primordial de garantir l’int\u00e9grit\u00e9 et la s\u00e9curit\u00e9 des donn\u00e9es. Une m\u00e9thode efficace pour v\u00e9rifier l’int\u00e9grit\u00e9 des fichiers consiste \u00e0 utiliser des valeurs de hachage. Une valeur de hachage agit comme une empreinte digitale num\u00e9rique des fichiers, permettant aux professionnels de l’informatique de v\u00e9rifier si les fichiers ont \u00e9t\u00e9 alt\u00e9r\u00e9s ou corrompus. Cet article se penche sur un script PowerShell con\u00e7u pour rechercher des fichiers avec des valeurs de hachage sp\u00e9cifiques, ce qui en fait un outil pr\u00e9cieux pour les professionnels de l’informatique et les fournisseurs de services g\u00e9r\u00e9s (MSP)<\/a>.<\/p>\n

Contexte<\/h2>\n

Le script PowerShell fourni est con\u00e7u pour alerter les utilisateurs si un fichier avec un hachage et une extension sp\u00e9cifi\u00e9s est trouv\u00e9 dans un r\u00e9pertoire donn\u00e9 et ses sous-r\u00e9pertoires. Le hachage des fichiers est une pratique courante en informatique pour v\u00e9rifier l’int\u00e9grit\u00e9 des fichiers et d\u00e9tecter les modifications non autoris\u00e9es. Ce script simplifie et automatise le processus, ce qui permet aux professionnels de l’informatique de garantir plus facilement la s\u00e9curit\u00e9 et l’int\u00e9grit\u00e9 de leurs syst\u00e8mes.<\/p>\n

Le script<\/h2>\n
#Requires -Version 5.1\r\n\r\n<#\r\n.SYNOPSIS\r\n    Alerts if a file with the extension and specified hash is found in the given search directory or subdirectories. Warning: Hashing large files may impact performance.\r\n.DESCRIPTION\r\n    Alerts if a file with the extension and specified hash is found in the given search directory or subdirectories. Warning: Hashing large files may impact performance.\r\n.EXAMPLE\r\n    -Hash \"F55A61A82F4F5943F86565E1FA2CCB4F\" -SearchPath \"C:\" -FileType \".ico\" -CustomField \"multiline\"\r\n    WARNING: Backslash missing from the search path. Changing it to C:\\.\r\n    WARNING: File with MD5 hash of F55A61A82F4F5943F86565E1FA2CCB4F found!\r\n\r\n    File Name         Path                                                                                    \r\n    ---------         ----                                                                                    \r\n    zoo_ecosystem.ico C:\\Users\\Administrator\\Desktop\\Find-FileHash\\Test Folder 1\\zoo_ecosystem.ico            \r\n    zoo_ecosystem.ico C:\\Users\\Administrator\\Desktop\\Find-FileHash\\TestFolder1\\Test Folder 1\\zoo_ecosystem.ico\r\n    zoo_ecosystem.ico C:\\Users\\Administrator\\Desktop\\Find-FileHash\\TestFolder2\\Test Folder 1\\zoo_ecosystem.ico\r\n\r\n    Attempting to set Custom Field 'multiline'.\r\n    Successfully set Custom Field 'multiline'!\r\n\r\nPARAMETER: -Hash \"REPLACEMEWITHAVALIDHASH\"\r\n    Files with this hash should cause the alert to trigger.\r\n\r\nPARAMETER: -Algorithm \"MD5\"\r\n    Hashing algorithm used for the above hash.\r\n\r\nPARAMETER: -SearchPath \"C:\\ReplaceMeWithAValidSearchPath\"\r\n   Specifies one or more starting directories for the search, separated by commas. The search will recursively include all subdirectories from these starting points.\r\n\r\nPARAMETER: -Timeout \"15\"\r\n    Once this timeout is reached, the script will stop searching for files that match your given hash.\r\n\r\nPARAMETER: -FileType \".exe\"\r\n    Specifies the file extension to filter the search. Only files with this extension will be analyzed for a hash match. Example: '.exe'\r\n\r\nPARAMETER: -CustomField \"NameOfMultiLineCustomField\"\r\n    Specifies the name of an optional multiline custom field where results can be sent. \r\n\r\n.NOTES\r\n    Minimum OS Architecture Supported: Windows 10, Windows Server 2016\r\n    Release Notes: Initial Release\r\nBy using this script, you indicate your acceptance of the following legal terms as well as our Terms of Use at https:\/\/www.ninjaone.com\/terms-of-use.\r\n    Ownership Rights: NinjaOne owns and will continue to own all right, title, and interest in and to the script (including the copyright). NinjaOne is giving you a limited license to use the script in accordance with these legal terms. \r\n    Use Limitation: You may only use the script for your legitimate personal or internal business purposes, and you may not share the script with another party. \r\n    Republication Prohibition: Under no circumstances are you permitted to re-publish the script in any script library or website belonging to or under the control of any other software provider. \r\n    Warranty Disclaimer: The script is provided \u201cas is\u201d and \u201cas available\u201d, without warranty of any kind. NinjaOne makes no promise or guarantee that the script will be free from defects or that it will meet your specific needs or expectations. \r\n    Assumption of Risk: Your use of the script is at your own risk. You acknowledge that there are certain inherent risks in using the script, and you understand and assume each of those risks. \r\n    Waiver and Release: You will not hold NinjaOne responsible for any adverse or unintended consequences resulting from your use of the script, and you waive any legal or equitable rights or remedies you may have against NinjaOne relating to your use of the script. \r\n    EULA: If you are a NinjaOne customer, your use of the script is subject to the End User License Agreement applicable to you (EULA).\r\n#>\r\n\r\n[CmdletBinding()]\r\nparam (\r\n    [Parameter()]\r\n    [String]$Hash,\r\n    [Parameter()]\r\n    [String]$SearchPath = \"C:\\Windows\",\r\n    [Parameter()]\r\n    [String]$FileType,\r\n    [Parameter()]\r\n    [Int]$Timeout = 15,\r\n    [Parameter()]\r\n    [String]$Algorithm = \"MD5\",\r\n    [Parameter()]\r\n    [String]$CustomField\r\n)\r\n\r\nbegin {\r\n    # Set parameters using dynamic script variables.\r\n    if ($env:hash -and $env:hash -notlike \"null\") { $Hash = $env:hash }\r\n    if ($env:hashType -and $env:hashType -notlike \"null\") { $Algorithm = $env:hashType }\r\n    if ($env:searchPath -and $env:searchPath -notlike \"null\") { $SearchPath = $env:searchPath }\r\n    if ($env:timeoutInMinutes -and $env:timeoutInMinutes -notlike \"null\") { $Timeout = $env:timeoutInMinutes }\r\n    if ($env:fileExtensionToSearchFor -and $env:fileExtensionToSearchFor -notlike \"null\") { $FileType = $env:fileExtensionToSearchFor }\r\n    if ($env:customFieldName -and $env:customFieldName -notlike \"null\") { $CustomField = $env:customFieldName }\r\n\r\n    # If given a comma-separated list, split the paths.\r\n    $PathsToSearch = New-Object System.Collections.Generic.List[String]\r\n    if ($SearchPath -match \",\") {\r\n        $SearchPath -split \",\" | ForEach-Object { $PathsToSearch.Add($_.Trim()) }\r\n    }\r\n    else {\r\n        $PathsToSearch.Add($SearchPath)\r\n    }\r\n\r\n    $ReplacementPaths = New-Object System.Collections.Generic.List[Object]\r\n    $PathsToRemove = New-Object System.Collections.Generic.List[String]\r\n\r\n    # If given a drive without the backslash add it in.\r\n    $PathsToSearch | ForEach-Object {\r\n        if ($_ -notmatch '^[A-Z]:\\\\$' -and $_ -match '^[A-Z]:$') {\r\n            $NewPath = \"$_\\\"\r\n            $ReplacementPaths.Add(\r\n                [PSCustomObject]@{\r\n                    Index   = $PathsToSearch.IndexOf(\"$_\")\r\n                    NewPath = $NewPath\r\n                }\r\n            )\r\n                \r\n            Write-Warning \"Backslash missing from the search path. Changing it to $NewPath.\"\r\n        }\r\n    }\r\n\r\n    # Apply replacements\r\n    $ReplacementPaths | ForEach-Object {\r\n        $PathsToSearch[$_.index] = $_.NewPath \r\n    }\r\n\r\n    # Check if the search path is valid.\r\n    $PathsToSearch | ForEach-Object {\r\n        if (-not (Test-Path $_)) {\r\n            Write-Host -Object \"[Error] $_ does not exist!\"\r\n            $PathsToRemove.Add($_)\r\n            $ExitCode = 1\r\n        }\r\n    }\r\n\r\n    $PathsToRemove | ForEach-Object {\r\n        $PathsToSearch.Remove($_) | Out-Null\r\n    }\r\n\r\n\r\n    # Error out if no valid paths to search.\r\n    if ($PathsToSearch.Count -eq 0) {\r\n        Write-Host \"[Error] No valid paths to search!\"\r\n        exit 1\r\n    }\r\n\r\n    # A file extension is required.\r\n    if (-not $FileType) {\r\n        Write-Host -Object \"[Error] File Type is required!\"\r\n        exit 1\r\n    }\r\n\r\n    # If we were given the extension without the . we'll add it back in\r\n    if ($FileType -notmatch '^\\.') {\r\n        $FileType = \".$FileType\"\r\n        Write-Warning -Message \"Extension missing changing filetype to $FileType.\"\r\n    }\r\n\r\n    # The timeout has to be between 1 and 120\r\n    if ($Timeout -lt 1 -or $Timeout -gt 120) {\r\n        Write-Host \"[Error] Invalid timeout given of $Timeout minutes. Please enter a value between 1 and 120.\"\r\n        exit 1\r\n    }\r\n\r\n    # PowerShell 5.1 supports more algorithms than this, however PowerShell 7 does not.\r\n    $ValidAlgorithms = \"SHA1\", \"SHA256\", \"SHA384\", \"SHA512\", \"MD5\"\r\n    if ($ValidAlgorithms -notcontains $Algorithm) {\r\n        Write-Host \"[Error] Invalid Algorithm selected. Only SHA1, SHA256, SHA384, SHA512 and MD5 are supported.\"\r\n        exit 1\r\n    }\r\n\r\n    # Helper function to make it easier to set custom fields.\r\n    function Set-NinjaProperty {\r\n        [CmdletBinding()]\r\n        Param(\r\n            [Parameter(Mandatory = $True)]\r\n            [String]$Name,\r\n            [Parameter()]\r\n            [String]$Type,\r\n            [Parameter(Mandatory = $True, ValueFromPipeline = $True)]\r\n            $Value,\r\n            [Parameter()]\r\n            [String]$DocumentName\r\n        )\r\n    \r\n        $Characters = $Value | Measure-Object -Character | Select-Object -ExpandProperty Characters\r\n        if ($Characters -ge 10000) {\r\n            throw [System.ArgumentOutOfRangeException]::New(\"Character limit exceeded, value is greater than 10,000 characters.\")\r\n        }\r\n        \r\n        # If we're requested to set the field value for a Ninja document we'll specify it here.\r\n        $DocumentationParams = @{}\r\n        if ($DocumentName) { $DocumentationParams[\"DocumentName\"] = $DocumentName }\r\n        \r\n        # This is a list of valid fields that can be set. If no type is given, it will be assumed that the input doesn't need to be changed.\r\n        $ValidFields = \"Attachment\", \"Checkbox\", \"Date\", \"Date or Date Time\", \"Decimal\", \"Dropdown\", \"Email\", \"Integer\", \"IP Address\", \"MultiLine\", \"MultiSelect\", \"Phone\", \"Secure\", \"Text\", \"Time\", \"URL\", \"WYSIWYG\"\r\n        if ($Type -and $ValidFields -notcontains $Type) { Write-Warning \"$Type is an invalid type! Please check here for valid types. https:\/\/ninjarmm.zendesk.com\/hc\/en-us\/articles\/16973443979789-Command-Line-Interface-CLI-Supported-Fields-and-Functionality\" }\r\n        \r\n        # The field below requires additional information to be set\r\n        $NeedsOptions = \"Dropdown\"\r\n        if ($DocumentName) {\r\n            if ($NeedsOptions -contains $Type) {\r\n                # We'll redirect the error output to the success stream to make it easier to error out if nothing was found or something else went wrong.\r\n                $NinjaPropertyOptions = Ninja-Property-Docs-Options -AttributeName $Name @DocumentationParams 2>&1\r\n            }\r\n        }\r\n        else {\r\n            if ($NeedsOptions -contains $Type) {\r\n                $NinjaPropertyOptions = Ninja-Property-Options -Name $Name 2>&1\r\n            }\r\n        }\r\n        \r\n        # If an error is received it will have an exception property, the function will exit with that error information.\r\n        if ($NinjaPropertyOptions.Exception) { throw $NinjaPropertyOptions }\r\n        \r\n        # The below type's require values not typically given in order to be set. The below code will convert whatever we're given into a format ninjarmm-cli supports.\r\n        switch ($Type) {\r\n            \"Checkbox\" {\r\n                # While it's highly likely we were given a value like \"True\" or a boolean datatype it's better to be safe than sorry.\r\n                $NinjaValue = [System.Convert]::ToBoolean($Value)\r\n            }\r\n            \"Date or Date Time\" {\r\n                # Ninjarmm-cli expects the  Date-Time to be in Unix Epoch time so we'll convert it here.\r\n                $Date = (Get-Date $Value).ToUniversalTime()\r\n                $TimeSpan = New-TimeSpan (Get-Date \"1970-01-01 00:00:00\") $Date\r\n                $NinjaValue = $TimeSpan.TotalSeconds\r\n            }\r\n            \"Dropdown\" {\r\n                # Ninjarmm-cli is expecting the guid of the option we're trying to select. So we'll match up the value we were given with a guid.\r\n                $Options = $NinjaPropertyOptions -replace '=', ',' | ConvertFrom-Csv -Header \"GUID\", \"Name\"\r\n                $Selection = $Options | Where-Object { $_.Name -eq $Value } | Select-Object -ExpandProperty GUID\r\n        \r\n                if (-not $Selection) {\r\n                    throw [System.ArgumentOutOfRangeException]::New(\"Value is not present in dropdown\")\r\n                }\r\n        \r\n                $NinjaValue = $Selection\r\n            }\r\n            default {\r\n                # All the other types shouldn't require additional work on the input.\r\n                $NinjaValue = $Value\r\n            }\r\n        }\r\n        \r\n        # We'll need to set the field differently depending on if its a field in a Ninja Document or not.\r\n        if ($DocumentName) {\r\n            $CustomField = Ninja-Property-Docs-Set -AttributeName $Name -AttributeValue $NinjaValue @DocumentationParams 2>&1\r\n        }\r\n        else {\r\n            $CustomField = Ninja-Property-Set -Name $Name -Value $NinjaValue 2>&1\r\n        }\r\n        \r\n        if ($CustomField.Exception) {\r\n            throw $CustomField\r\n        }\r\n    }\r\n\r\n    # Test for local administrator rights\r\n    function Test-IsElevated {\r\n        $id = [System.Security.Principal.WindowsIdentity]::GetCurrent()\r\n        $p = New-Object System.Security.Principal.WindowsPrincipal($id)\r\n        $p.IsInRole([System.Security.Principal.WindowsBuiltInRole]::Administrator)\r\n    }\r\n\r\n    $ExitCode = 0\r\n}\r\nprocess {\r\n    if (-not (Test-IsElevated)) {\r\n        Write-Host -Object \"[Error] Access Denied. Please run with Administrator privileges.\"\r\n        exit 1\r\n    }\r\n\r\n    # If we're given a file instead of a folder, we'll check if it matches anyways.\r\n    $PathsToSearch | ForEach-Object {\r\n        if (-not (Get-Item $_).PSIsContainer) {\r\n            Write-Warning \"The search path you gave is actually a file not a folder. Checking the hash of the file...\"\r\n        }\r\n    }\r\n    \r\n    $HashJobs = New-Object System.Collections.Generic.List[object]\r\n    $MatchingFiles = New-Object System.Collections.Generic.List[object]\r\n    $CustomFieldValue = New-Object System.Collections.Generic.List[string]\r\n\r\n    # We'll use a PowerShell job so that we can timeout appropriately.\r\n    $PathsToSearch | ForEach-Object {\r\n        $HashJobs.Add(\r\n            (\r\n                Start-Job -ScriptBlock {\r\n                    param($SearchPath, $FileType, $Algorithm, $Hash)\r\n                    $Files = Get-ChildItem -Path $SearchPath -Filter \"*$FileType\" -File -Recurse\r\n                    $Files | ForEach-Object {\r\n                        $CurrentHash = Get-FileHash -Path $_.FullName -Algorithm $Algorithm\r\n                        if ($CurrentHash.Hash -match $Hash) { $_.FullName }\r\n                    }\r\n                } -ArgumentList $_, $FileType, $Algorithm, $Hash\r\n            )\r\n        )\r\n    }\r\n\r\n    $TimeoutInSeconds = $Timeout * 60\r\n    $StartTime = Get-Date\r\n\r\n    # Wait for all jobs to complete or timeout\r\n    foreach ($HashJob in $HashJobs) {\r\n        # Calculate the remaining time\r\n        $TimeElapsed = (Get-Date) - $StartTime\r\n        $RemainingTime = $TimeoutInSeconds - $TimeElapsed.TotalSeconds\r\n    \r\n        # If there is no remaining time, break the loop\r\n        if ($RemainingTime -le 0) {\r\n            break\r\n        }\r\n    \r\n        # Wait for the current job with the remaining time as the timeout\r\n        $HashJob | Wait-Job -Timeout $RemainingTime | Out-Null\r\n    }\r\n\r\n    # If we failed to complete the job, we'll output a warning.\r\n    $IncompleteJobs = $HashJobs | Get-Job | Where-Object { $_.State -eq \"Running\" }\r\n    if ($IncompleteJobs) {\r\n        Write-Host \"[Error] The timeout period of $Timeout minutes has been reached, but some files still require a hash check!\"\r\n        $CustomFieldValue.Add(\"[Error] The timeout period of $Timeout minutes has been reached, but some files still require a hash check!\")\r\n        $ExitCode = 1\r\n    }\r\n\r\n    # Receive the data from the job.\r\n    $HashJobs | Receive-Job -ErrorAction SilentlyContinue -ErrorVariable JobErrors | ForEach-Object {\r\n        $MatchingFiles.Add(\r\n            [PSCustomObject]@{\r\n                \"File Name\" = $(Split-Path $_ -Leaf)\r\n                Path        = $_\r\n            }\r\n        )\r\n    }\r\n\r\n    # If we have any matching files, we'll output them here.\r\n    if ($MatchingFiles) {\r\n        Write-Warning -Message \"File with $Algorithm hash of $Hash found!\"\r\n        $MatchingFiles | Format-Table -AutoSize | Out-String | Write-Host\r\n        $MatchingFiles | Select-Object -ExpandProperty Path | ForEach-Object { $CustomFieldValue.Add($_) }\r\n    }\r\n    else {\r\n        Write-Host -Object \"No files found with $Hash.\"\r\n    }\r\n\r\n    # If we received any failures or errors, we'll output that here.\r\n    $FailedJobs = $HashJobs | Get-Job | Where-Object { $_.State -ne \"Completed\" -and $_.State -ne \"Running\" }\r\n    if ($FailedJobs -or $JobErrors) {\r\n        Write-Host \"\"\r\n        Write-Host \"[Error] Failed to get the hash of certain files due to an error.\"\r\n        $CustomFieldValue.Add(\" \")\r\n        $CustomFieldValue.Add(\"[Error] Failed to get the hash of certain files due to an error.\")\r\n        if ($JobErrors) {\r\n            Write-Host \"\"\r\n            $JobErrors | ForEach-Object { Write-Host \"[Error] $($_.Exception.Message)\" }\r\n            $CustomFieldValue.Add(\" \")\r\n            $JobErrors | ForEach-Object { $CustomFieldValue.Add(\"[Error] $($_.Exception.Message)\") }\r\n        }\r\n        $ExitCode = 1\r\n    }\r\n\r\n    $HashJobs | Remove-Job -Force\r\n\r\n    # If we're given a custom field, we'll attempt to save the results to it.\r\n    if ($CustomField) {\r\n        try {\r\n            Write-Host \"Attempting to set Custom Field '$CustomField'.\"\r\n            Set-NinjaProperty -Name $CustomField -Value ($CustomFieldValue | Out-String)\r\n            Write-Host \"Successfully set Custom Field '$CustomField'!\"\r\n        }\r\n        catch {\r\n            if (-not $_.Exception.Message) {\r\n                Write-Host \"[Error] $($_.Message)\"\r\n            }\r\n            else {\r\n                Write-Host \"[Error] $($_.Exception.Message)\"\r\n            }\r\n            $ExitCode = 1\r\n        }\r\n        \r\n    }\r\n\r\n    exit $ExitCode\r\n}\r\nend {\r\n    \r\n    \r\n    \r\n}<\/pre>\n
 <\/p>\n\n
<\/div>\n
Description d\u00e9taill\u00e9e<\/h2>\n
Le script commence par des informations sur les m\u00e9tadonn\u00e9es, notamment un synopsis, une description et un exemple d’utilisation. Il d\u00e9finit les param\u00e8tres que l’utilisateur peut sp\u00e9cifier, tels que la valeur de hachage, le chemin de recherche, le type de fichier, l’algorithme de hachage, le d\u00e9lai d’attente et un champ personnalis\u00e9 facultatif pour les r\u00e9sultats de sortie.<\/p>\n
Configuration des param\u00e8tres<\/h3>\n