将安全字符串转换为纯文本

Question

我在 PowerShell 中工作，我有成功将用户输入的密码转换为纯文本的代码：

$SecurePassword = Read-Host -AsSecureString  "Enter password" | convertfrom-securestring | out-file C:\Users\tmarsh\Documents\securePassword.txt

我已经尝试了几种方法将其转换回来，但 none 似乎可以正常工作。最近，我尝试了以下方法：

$PlainPassword = Get-Content C:\Users\tmarsh\Documents\securePassword.txt

#convert the SecureString object to plain text using PtrToString and SecureStringToBSTR
$BSTR = [System.Runtime.InteropServices.Marshal]::SecureStringToBSTR($PlainPassword)
$PlainPassword = [System.Runtime.InteropServices.Marshal]::PtrToStringAuto($BSTR)
[Runtime.InteropServices.Marshal]::ZeroFreeBSTR($BSTR) #this is an important step to keep things secure

这也给我一个错误。

Cannot convert argument "s", with value: "01000000d08c9ddf0115d1118c7a00c04fc297eb0100000026a5b6067d53fd43801a9ef3f8ef9e43000000000200000000000366000
0c0000000100000008118fdea02bfb57d0dda41f9748a05f10000000004800000a000000010000000c50f5093f3b87fbf9ee57cbd17267e0a10000000833d1d712cef01497872a3457bc8
bc271400000038c731cb8c47219399e4265515e9569438d8e8ed", for "SecureStringToBSTR" to type "System.Security.SecureString": "Cannot convert the "01000000
d08c9ddf0115d1118c7a00c04fc297eb0100000026a5b6067d53fd43801a9ef3f8ef9e430000000002000000000003660000c0000000100000008118fdea02bfb57d0dda41f9748a05f10
000000004800000a000000010000000c50f5093f3b87fbf9ee57cbd17267e0a10000000833d1d712cef01497872a3457bc8bc271400000038c731cb8c47219399e4265515e9569438d8e8
ed" value of type "System.String" to type "System.Security.SecureString"."
At C:\Users\tmarsh\Documents\Scripts\Local Admin Script\PlainTextConverter1.ps1:14 char:1
+ $BSTR = [System.Runtime.InteropServices.Marshal]::SecureStringToBSTR($PlainPassw ...
+ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    + CategoryInfo          : NotSpecified: (:) [], MethodException
    + FullyQualifiedErrorId : MethodArgumentConversionInvalidCastArgument

Cannot find an overload for "PtrToStringAuto" and the argument count: "1".
At C:\Users\tmarsh\Documents\Scripts\Local Admin Script\PlainTextConverter1.ps1:15 char:1
+ $PlainPassword = [System.Runtime.InteropServices.Marshal]::PtrToStringAuto($BSTR ...
+ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    + CategoryInfo          : NotSpecified: (:) [], MethodException
    + FullyQualifiedErrorId : MethodCountCouldNotFindBest

Cannot convert argument "s", with value: "", for "ZeroFreeBSTR" to type "System.IntPtr": "Cannot convert null to type "System.IntPtr"."
At C:\Users\tmarsh\Documents\Scripts\Local Admin Script\PlainTextConverter1.ps1:16 char:1
+ [Runtime.InteropServices.Marshal]::ZeroFreeBSTR($BSTR) #this is an important ste ...
+ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    + CategoryInfo          : NotSpecified: (:) [], MethodException
    + FullyQualifiedErrorId : MethodArgumentConversionInvalidCastArgument

Password is:  01000000d08c9ddf0115d1118c7a00c04fc297eb0100000026a5b6067d53fd43801a9ef3f8ef9e430000000002000000000003660000c0000000100000008118fdea02bfb57d0dda41f97
48a05f10000000004800000a000000010000000c50f5093f3b87fbf9ee57cbd17267e0a10000000833d1d712cef01497872a3457bc8bc271400000038c731cb8c47219399e4265515e9569
438d8e8ed

有谁知道可以解决这个问题的方法吗？

Answer 1

你很接近，但是你传递给SecureStringToBSTR的参数必须是一个SecureString。您似乎传递了 ConvertFrom-SecureString 的结果，这是一个加密的标准字符串。所以在传递给 SecureStringToBSTR.

之前调用 ConvertTo-SecureString

$SecurePassword = ConvertTo-SecureString $PlainPassword -AsPlainText -Force
$BSTR = [System.Runtime.InteropServices.Marshal]::SecureStringToBSTR($SecurePassword)
$UnsecurePassword = [System.Runtime.InteropServices.Marshal]::PtrToStringAuto($BSTR)

Answer 2

您也可以使用 PSCredential.GetNetworkCredential() :

$SecurePassword = Get-Content C:\Users\tmarsh\Documents\securePassword.txt | ConvertTo-SecureString
$UnsecurePassword = (New-Object PSCredential "user",$SecurePassword).GetNetworkCredential().Password

Answer 3

在 PowerShell 中转换回它的最简单方法

[System.Net.NetworkCredential]::new("", $SecurePassword).Password

Answer 4

在PS7中，可以使用ConvertFrom-SecureString和-AsPlainText：

#Requires -Version 7.0 

$UnsecurePassword = ConvertFrom-SecureString -SecureString $SecurePassword -AsPlainText

https://docs.microsoft.com/en-us/powershell/module/microsoft.powershell.security/ConvertFrom-SecureString?view=powershell-7#parameters

ConvertFrom-SecureString
           [-SecureString] <SecureString>
           [-AsPlainText]
           [<CommonParameters>]

将安全字符串转换为纯文本

Convert a secure string to plain text

powershell

securestring