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alan-nullalan-null
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Added ability to export keys to PEM format
1 parent 4a705b2 commit 98ee44d

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5 files changed

+171
-1
lines changed

5 files changed

+171
-1
lines changed

‎Crypto.RSA/Private/EncodeIntegerBigEndian.ps1

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function EncodeIntegerBigEndian {
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[CmdletBinding()]
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param (
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[Parameter(Mandatory = $true, Position = 0 )]
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[System.IO.BinaryWriter]$stream,
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[Parameter(Mandatory = $true, Position = 1 )]
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[byte[]]$value,
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[Parameter(Mandatory = $false, Position = 2 )]
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[bool]$forceUnsigned = $true
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)
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process {
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$stream.Write([byte]0x02); # INTEGER
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$prefixZeros = 0;
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for ($i = 0; $i -lt $value.Length; $i++) {
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if ($value[$i] -ne 0) {
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break
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}
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$prefixZeros++;
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}
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if ($value.Length - $prefixZeros -eq 0) {
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EncodeLength $stream 1
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$stream.Write([byte]0);
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}
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else {
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if ($forceUnsigned -and $value[$prefixZeros] -gt 0x7f) {
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# Add a prefix zero to force unsigned if the MSB is 1
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EncodeLength $stream ($value.Length - $prefixZeros + 1)
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$stream.Write([byte]0);
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}
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else {
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EncodeLength $stream ($value.Length - $prefixZeros)
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}
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for ($i = $prefixZeros; $i -lt $value.Length; $i++) {
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$stream.Write($value[$i]);
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}
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}
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}
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}

‎Crypto.RSA/Private/EncodeLength.ps1

Lines changed: 32 additions & 0 deletions
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function EncodeLength {
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[CmdletBinding()]
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param (
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[Parameter(Mandatory = $true, Position = 0 )]
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[System.IO.BinaryWriter]$stream,
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[Parameter(Mandatory = $true, Position = 1 )]
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[int]$length
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)
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process {
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if ($length -lt 0) {
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throw [System.ArgumentOutOfRangeException]::new("$length", "Length must be non-negative")
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}
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if ($length -lt 0x80) {
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# Short form
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$stream.Write([byte]$length)
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}
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else {
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# Long form
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$temp = $length;
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$bytesRequired = 0;
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while ($temp -gt 0) {
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$temp = $temp -shr 8;
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$bytesRequired++;
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}
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$stream.Write([byte]($bytesRequired -bor 0x80));
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for ($i = $bytesRequired - 1; $i -ge 0; $i--) {
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$stream.Write([byte]($length -shr (8 * $i) -band 0xff));
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}
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}
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}
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}

‎Crypto.RSA/Public/Export-PrivateKey.ps1

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# src: https://gist.github.com/therightstuff/aa65356e95f8d0aae888e9f61aa29414
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function Export-PrivateKey {
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param (
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[Parameter(Mandatory = $true, Position = 0 )]
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[System.Security.Cryptography.RSACryptoServiceProvider]$csp
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)
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$outputStream = [System.IO.StringWriter]::new()
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if ($csp.PublicOnly) {
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throw [System.ArgumentException]::new("CSP does not contain a private key", "csp")
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}
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$parameters = $csp.ExportParameters($true);
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Use ($stream = [System.IO.MemoryStream]::new()) {
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$writer = [System.IO.BinaryWriter]::new($stream);
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$writer.Write([byte]0x30); # SEQUENCE
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Use ($innerStream = [System.IO.MemoryStream]::new()) {
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$innerWriter = [System.IO.BinaryWriter]::new($innerStream);
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EncodeIntegerBigEndian $innerWriter @([byte]0x00)
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EncodeIntegerBigEndian $innerWriter $parameters.Modulus
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EncodeIntegerBigEndian $innerWriter $parameters.Exponent
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EncodeIntegerBigEndian $innerWriter $parameters.D
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EncodeIntegerBigEndian $innerWriter $parameters.P
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EncodeIntegerBigEndian $innerWriter $parameters.Q
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EncodeIntegerBigEndian $innerWriter $parameters.DP
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EncodeIntegerBigEndian $innerWriter $parameters.DQ
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EncodeIntegerBigEndian $innerWriter $parameters.InverseQ
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[int]$length = $innerStream.Length;
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EncodeLength $writer $length
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$writer.Write($innerStream.GetBuffer(), 0, $length);
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}
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$base64 = [System.Convert]::ToBase64String($stream.GetBuffer(), 0, [int]$stream.Length).ToCharArray();
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$outputStream.Write("-----BEGIN RSA PRIVATE KEY-----`n");
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for ($i = 0; $i -lt $base64.Length; $i += 64) {
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$outputStream.Write($base64, $i, [System.Math]::Min(64, $base64.Length - $i));
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$outputStream.Write("`n");
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}
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$outputStream.Write("-----END RSA PRIVATE KEY-----");
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}
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return $outputStream.ToString();
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}

‎Crypto.RSA/Public/Export-PublicKey.ps1

Lines changed: 55 additions & 0 deletions
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# src: https://gist.github.com/therightstuff/aa65356e95f8d0aae888e9f61aa29414
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function Export-PublicKey {
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param (
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[Parameter(Mandatory = $true, Position = 0 )]
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[System.Security.Cryptography.RSACryptoServiceProvider]$csp
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)
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$outputStream = [System.IO.StringWriter]::new()
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$parameters = $csp.ExportParameters($false);
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Use ( $stream = [System.IO.MemoryStream]::new()) {
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$writer = [System.IO.BinaryWriter]::new($stream);
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$writer.Write([byte]0x30); # SEQUENCE
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Use ($innerStream = [System.IO.MemoryStream]::new()) {
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$innerWriter = [System.IO.BinaryWriter]::new($innerStream);
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$innerWriter.Write([byte]0x30); # SEQUENCE
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EncodeLength $innerWriter 13
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$innerWriter.Write([byte]0x06); # OBJECT IDENTIFIER
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$rsaEncryptionOid = @(0x2a, 0x86, 0x48, 0x86, 0xf7, 0x0d, 0x01, 0x01, 0x01 )
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EncodeLength $innerWriter $rsaEncryptionOid.Length
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$innerWriter.Write($rsaEncryptionOid);
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$innerWriter.Write([byte]0x05); # NULL
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EncodeLength $innerWriter 0
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$innerWriter.Write([byte]0x03); # BIT STRING
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Use ($bitStringStream = [System.IO.MemoryStream]::new()) {
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$bitStringWriter = [System.IO.BinaryWriter]::new($bitStringStream);
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$bitStringWriter.Write([byte]0x00); # # of unused bits
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$bitStringWriter.Write([byte]0x30); # SEQUENCE
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Use ($paramsStream = [System.IO.MemoryStream]::new()) {
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$paramsWriter = [System.IO.BinaryWriter]::new($paramsStream);
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EncodeIntegerBigEndian $paramsWriter $parameters.Modulus # Modulus
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EncodeIntegerBigEndian $paramsWriter $parameters.Exponent # Exponent
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[int]$paramsLength = $paramsStream.Length;
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EncodeLength $bitStringWriter $paramsLength
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$bitStringWriter.Write($paramsStream.GetBuffer(), 0, $paramsLength);
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}
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[int]$bitStringLength = $bitStringStream.Length;
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EncodeLength $innerWriter $bitStringLength
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$innerWriter.Write($bitStringStream.GetBuffer(), 0, $bitStringLength);
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}
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[int]$length = $innerStream.Length;
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EncodeLength $writer $length
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$writer.Write($innerStream.GetBuffer(), 0, $length);
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}
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$base64 = [System.Convert]::ToBase64String($stream.GetBuffer(), 0, [int]$stream.Length).ToCharArray();
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$outputStream.Write("-----BEGIN PUBLIC KEY-----`n");
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for ($i = 0; $i -lt $base64.Length; $i += 64) {
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$outputStream.Write($base64, $i, [System.Math]::Min(64, $base64.Length - $i));
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$outputStream.Write("`n");
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}
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$outputStream.Write("-----END PUBLIC KEY-----");
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}
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return $outputStream.ToString();
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}

‎Crypto.RSA/Public/Get-KeyString.ps1

Lines changed: 1 addition & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -2,7 +2,7 @@ function Get-KeyString {
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[CmdletBinding()]
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param (
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[Parameter(Mandatory = $true, Position = 0 )]
5-
[System.Security.Cryptography.RSAParameters]$publicKey
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[System.Security.Cryptography.RSAParameters]$publicKey
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)
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begin {

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