public static unsafe bool TryExportToPem <T>(
T arg,
string label,
TryExportKeyAction <T> exporter,
Span <char> destination,
out int charsWritten)
{
int bufferSize = 4096;
while (true)
{
byte[] buffer = CryptoPool.Rent(bufferSize);
int bytesWritten = 0;
bufferSize = buffer.Length;
// Fixed to prevent GC moves.
fixed(byte *bufferPtr = buffer)
{
try
{
if (exporter(arg, buffer, out bytesWritten))
{
Span <byte> writtenSpan = new Span <byte>(buffer, 0, bytesWritten);
return(PemEncoding.TryWrite(label, writtenSpan, destination, out charsWritten));
}
}
finally
{
CryptoPool.Return(buffer, bytesWritten);
}
bufferSize = checked (bufferSize * 2);
}
}
}
public static void ImportEncryptedPem <TPass>(
ReadOnlySpan <char> input,
ReadOnlySpan <TPass> password,
ImportEncryptedKeyAction <TPass> importAction)
{
bool foundEncryptedPem = false;
PemFields foundFields = default;
ReadOnlySpan <char> foundSlice = default;
ReadOnlySpan <char> pem = input;
while (PemEncoding.TryFind(pem, out PemFields fields))
{
ReadOnlySpan <char> label = pem[fields.Label];
if (label.SequenceEqual(PemLabels.EncryptedPkcs8PrivateKey))
{
if (foundEncryptedPem)
{
throw new ArgumentException(SR.Argument_PemImport_AmbiguousPem, nameof(input));
}
foundEncryptedPem = true;
foundFields = fields;
foundSlice = pem;
}
Index offset = fields.Location.End;
pem = pem[offset..];
internal static string CreatePemFromData(string label, ReadOnlyMemory <byte> data)
{
int pemSize = PemEncoding.GetEncodedSize(label.Length, data.Length);
return(string.Create(pemSize, (label, data), static (destination, args) =>
{
(string label, ReadOnlyMemory <byte> data) = args;
if (!PemEncoding.TryWrite(label, data.Span, destination, out int charsWritten) ||
charsWritten != destination.Length)
{
Debug.Fail("Pre-allocated buffer was not the correct size.");
throw new CryptographicException();
}
}));
public static unsafe bool TryExportToEncryptedPem <T>(
T arg,
ReadOnlySpan <char> password,
PbeParameters pbeParameters,
TryExportEncryptedKeyAction <T> exporter,
Span <char> destination,
out int charsWritten)
{
int bufferSize = 4096;
while (true)
{
byte[] buffer = CryptoPool.Rent(bufferSize);
int bytesWritten = 0;
bufferSize = buffer.Length;
// Fixed to prevent GC moves.
fixed(byte *bufferPtr = buffer)
{
try
{
if (exporter(arg, password, pbeParameters, buffer, out bytesWritten))
{
Span <byte> writtenSpan = new Span <byte>(buffer, 0, bytesWritten);
return(PemEncoding.TryWrite(PemLabels.EncryptedPkcs8PrivateKey, writtenSpan, destination, out charsWritten));
}
}
finally
{
CryptoPool.Return(buffer, bytesWritten);
}
bufferSize = checked (bufferSize * 2);
}
}
}