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ConvertFrom-SecureString
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NAME ConvertFrom-SecureString
SYNOPSIS
Converts a secure string to an encrypted standard string.
SYNTAX
ConvertFrom-SecureString [-SecureString] <SecureString> [-Key <Byte[]>] [<CommonParameters>]
ConvertFrom-SecureString [-SecureString] <SecureString> [[-SecureKey] <SecureString>] [<CommonParameters>]
DESCRIPTION
The ConvertFrom-SecureString cmdlet converts a secure string ( System.Security.SecureString ) to an encrypted standard string ( System.String ).
Unlike a secure string, an encrypted standard string can be saved in a file for later use. The encrypted standard string can be converted back to
a secure string by using the ConvertTo-SecureString cmdlet.
If an encryption key is specified by using the Key or SecureKey parameters, the Advanced Encryption Standard (AES) encryption algorithm is used.
The specified key must have a length of 128, 192, or 256 bits, because those are the key lengths supported by the AES encryption algorithm. If no
key is specified, the Windows Data Protection API (DPAPI) is used to encrypt the standard string representation.
PARAMETERS
-Key <Byte[]>
Specifies the encryption key as a byte array.
Required? false
Position? named
Default value None
Accept pipeline input? False
Accept wildcard characters? false
-SecureKey <SecureString>
Specifies the encryption key as a secure string. The secure string value is converted to a byte array before being used as the key.
Required? false
Position? 1
Default value None
Accept pipeline input? False
Accept wildcard characters? false
-SecureString <SecureString>
Specifies the secure string to convert to an encrypted standard string.
Required? true
Position? 0
Default value None
Accept pipeline input? True (ByValue)
Accept wildcard characters? false
<CommonParameters>
This cmdlet supports the common parameters: Verbose, Debug,
ErrorAction, ErrorVariable, WarningAction, WarningVariable,
OutBuffer, PipelineVariable, and OutVariable. For more information, see
about_CommonParameters (http://go.microsoft.com/fwlink/?LinkID=113216).
INPUTS
System.Security.SecureString
You can pipe a SecureString object to ConvertFrom-SecureString .
OUTPUTS
System.String
ConvertFrom-SecureString returns a standard string object.
NOTES
To create a secure string from characters that are typed at the command prompt, use the AsSecureString* parameter of the Read-Host cmdlet.
When you use the Key or SecureKey parameters to specify a key, the key length must be correct. For example, a key of 128 bits can be specified
as a byte array of 16 digits. Similarly, 192-bit and 256-bit keys correspond to byte arrays of 24 and 32 digits, respectively.
*
Example 1: Create a secure string
PS C:\\>$SecureString = Read-Host -AsSecureString
This command creates a secure string from characters that you type at the command prompt. After entering the command, type the string you want to
store as a secure string. An asterisk (*) is displayed to represent each character that you type.
Example 2: Convert a secure string to an encrypted standard string
PS C:\\>$StandardString = ConvertFrom-SecureString $SecureString
This command converts the secure string in the $SecureString variable to an encrypted standard string. The resulting encrypted standard string is
stored in the $StandardString variable.
Example 3: Convert a secure string to an encrypted standard string with a 192-bit key
PS C:\\>$Key = (3,4,2,3,56,34,254,222,1,1,2,23,42,54,33,233,1,34,2,7,6,5,35,43)
PS C:\\>$StandardString = ConvertFrom-SecureString $SecureString -Key $Key
These commands use the AES algorithm to convert the secure string stored in the $SecureString variable to an encrypted standard string with a
192-bit key. The resulting encrypted standard string is stored in the $StandardString variable.
The first command stores a key in the $Key variable. The key is an array of 24 digits, all of which are less than 256.
Because each digit represents a byte (8 bits), the key has 24 digits for a total of 192 bits (8 x 24). This is a valid key length for the AES
algorithm. Each individual value is less than 256, which is the maximum value that can be stored in an unsigned byte.
The second command uses the key in the $Key variable to convert the secure string to an encrypted standard string.
RELATED LINKS
Online Version: http://go.microsoft.com/fwlink/?LinkId=821708
ConvertTo-SecureString
SYNOPSIS
Converts a secure string to an encrypted standard string.
SYNTAX
ConvertFrom-SecureString [-SecureString] <SecureString> [-Key <Byte[]>] [<CommonParameters>]
ConvertFrom-SecureString [-SecureString] <SecureString> [[-SecureKey] <SecureString>] [<CommonParameters>]
DESCRIPTION
The ConvertFrom-SecureString cmdlet converts a secure string ( System.Security.SecureString ) to an encrypted standard string ( System.String ).
Unlike a secure string, an encrypted standard string can be saved in a file for later use. The encrypted standard string can be converted back to
a secure string by using the ConvertTo-SecureString cmdlet.
If an encryption key is specified by using the Key or SecureKey parameters, the Advanced Encryption Standard (AES) encryption algorithm is used.
The specified key must have a length of 128, 192, or 256 bits, because those are the key lengths supported by the AES encryption algorithm. If no
key is specified, the Windows Data Protection API (DPAPI) is used to encrypt the standard string representation.
PARAMETERS
-Key <Byte[]>
Specifies the encryption key as a byte array.
Required? false
Position? named
Default value None
Accept pipeline input? False
Accept wildcard characters? false
-SecureKey <SecureString>
Specifies the encryption key as a secure string. The secure string value is converted to a byte array before being used as the key.
Required? false
Position? 1
Default value None
Accept pipeline input? False
Accept wildcard characters? false
-SecureString <SecureString>
Specifies the secure string to convert to an encrypted standard string.
Required? true
Position? 0
Default value None
Accept pipeline input? True (ByValue)
Accept wildcard characters? false
<CommonParameters>
This cmdlet supports the common parameters: Verbose, Debug,
ErrorAction, ErrorVariable, WarningAction, WarningVariable,
OutBuffer, PipelineVariable, and OutVariable. For more information, see
about_CommonParameters (http://go.microsoft.com/fwlink/?LinkID=113216).
INPUTS
System.Security.SecureString
You can pipe a SecureString object to ConvertFrom-SecureString .
OUTPUTS
System.String
ConvertFrom-SecureString returns a standard string object.
NOTES
To create a secure string from characters that are typed at the command prompt, use the AsSecureString* parameter of the Read-Host cmdlet.
When you use the Key or SecureKey parameters to specify a key, the key length must be correct. For example, a key of 128 bits can be specified
as a byte array of 16 digits. Similarly, 192-bit and 256-bit keys correspond to byte arrays of 24 and 32 digits, respectively.
*
Example 1: Create a secure string
PS C:\\>$SecureString = Read-Host -AsSecureString
This command creates a secure string from characters that you type at the command prompt. After entering the command, type the string you want to
store as a secure string. An asterisk (*) is displayed to represent each character that you type.
Example 2: Convert a secure string to an encrypted standard string
PS C:\\>$StandardString = ConvertFrom-SecureString $SecureString
This command converts the secure string in the $SecureString variable to an encrypted standard string. The resulting encrypted standard string is
stored in the $StandardString variable.
Example 3: Convert a secure string to an encrypted standard string with a 192-bit key
PS C:\\>$Key = (3,4,2,3,56,34,254,222,1,1,2,23,42,54,33,233,1,34,2,7,6,5,35,43)
PS C:\\>$StandardString = ConvertFrom-SecureString $SecureString -Key $Key
These commands use the AES algorithm to convert the secure string stored in the $SecureString variable to an encrypted standard string with a
192-bit key. The resulting encrypted standard string is stored in the $StandardString variable.
The first command stores a key in the $Key variable. The key is an array of 24 digits, all of which are less than 256.
Because each digit represents a byte (8 bits), the key has 24 digits for a total of 192 bits (8 x 24). This is a valid key length for the AES
algorithm. Each individual value is less than 256, which is the maximum value that can be stored in an unsigned byte.
The second command uses the key in the $Key variable to convert the secure string to an encrypted standard string.
RELATED LINKS
Online Version: http://go.microsoft.com/fwlink/?LinkId=821708
ConvertTo-SecureString