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セキュリティで保護された文字列をプレーンテキストに変換する

私はPowerShellで働いており、ユーザーが入力したパスワードをプレーンテキストに正常に変換するコードがあります:

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

私はそれを元に戻すいくつかの方法を試しましたが、どれも適切に動作しないようです。ごく最近、私は次のことを試しました:

$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

これは私にもエラーを与えます。

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

誰でもこれに役立つ方法を知っていますか?

56
tmarsh

近いですが、SecureStringToBSTRに渡すパラメーターはSecureStringでなければなりません。暗号化された標準文字列であるConvertFrom-SecureStringの結果を渡しているようです。 SecureStringToBSTRに渡す前に、ConvertTo-SecureStringを呼び出してください。

$SecurePassword = ConvertTo-SecureString $PlainPassword
$BSTR = [System.Runtime.InteropServices.Marshal]::SecureStringToBSTR($SecurePassword)
$UnsecurePassword = [System.Runtime.InteropServices.Marshal]::PtrToStringAuto($BSTR)
96
MatthewG

PSCredential.GetNetworkCredential()を使用することもできます:

$SecurePassword = Get-Content C:\Users\tmarsh\Documents\securePassword.txt | ConvertTo-SecureString
$UnsecurePassword = (New-Object PSCredential "user",$SecurePassword).GetNetworkCredential().Password
58
Nicolas Melay

PowerShellで変換する最も簡単な方法

[System.Net.NetworkCredential]::new("", $SecurePassword).Password
4