public DSACng(CngKey key)
{
if (key == null)
{
throw new ArgumentNullException("key");
}
if (key.AlgorithmGroup != CngAlgorithmGroup.Dsa)
{
throw new ArgumentException(SR.GetString(SR.Cryptography_ArgDSARequiresDSAKey), "key");
}
LegalKeySizesValue = s_legalKeySizes;
CngKey cngKey = CngKey.Open(key.Handle, key.IsEphemeral ? CngKeyHandleOpenOptions.EphemeralKey : CngKeyHandleOpenOptions.None);
Key = cngKey;
}
public ECDsaCng(CngKey key)
{
this.m_hashAlgorithm = CngAlgorithm.Sha256;
if (key == null)
{
throw new ArgumentNullException("key");
}
if (key.AlgorithmGroup != CngAlgorithmGroup.ECDsa)
{
throw new ArgumentException(System.SR.GetString("Cryptography_ArgECDsaRequiresECDsaKey"), "key");
}
if (!NCryptNative.NCryptSupported)
{
throw new PlatformNotSupportedException(System.SR.GetString("Cryptography_PlatformNotSupported"));
}
base.LegalKeySizesValue = s_legalKeySizes;
new SecurityPermission(SecurityPermissionFlag.UnmanagedCode).Assert();
this.Key = CngKey.Open(key.Handle, key.IsEphemeral ? CngKeyHandleOpenOptions.EphemeralKey : CngKeyHandleOpenOptions.None);
CodeAccessPermission.RevertAssert();
this.KeySize = this.m_key.KeySize;
}
public ECDiffieHellmanCng(CngKey key)
{
Contract.Ensures(LegalKeySizesValue != null);
Contract.Ensures(m_key != null && m_key.AlgorithmGroup == CngAlgorithmGroup.ECDiffieHellman);
if (key == null)
{
throw new ArgumentNullException("key");
}
if (key.AlgorithmGroup != CngAlgorithmGroup.ECDiffieHellman)
{
throw new ArgumentException(SR.GetString(SR.Cryptography_ArgECDHRequiresECDHKey), "key");
}
if (!NCryptNative.NCryptSupported)
{
throw new PlatformNotSupportedException(SR.GetString(SR.Cryptography_PlatformNotSupported));
}
LegalKeySizesValue = s_legalKeySizes;
// Make a copy of the key so that we continue to work if it gets disposed before this algorithm
//
// This requires an assert for UnmanagedCode since we'll need to access the raw handles of the key
// and the handle constructor of CngKey. The assert is safe since ECDiffieHellmanCng will never
// expose the key handles to calling code (without first demanding UnmanagedCode via the Handle
// property of CngKey).
//
// The bizzare looking disposal of the key.Handle property is intentional - Handle returns a
// duplicate - without disposing it, we keep the key alive until the GC runs.
new SecurityPermission(SecurityPermissionFlag.UnmanagedCode).Assert();
using (SafeNCryptKeyHandle importHandle = key.Handle) {
Key = CngKey.Open(importHandle, key.IsEphemeral ? CngKeyHandleOpenOptions.EphemeralKey : CngKeyHandleOpenOptions.None);
}
CodeAccessPermission.RevertAssert();
KeySize = m_key.KeySize;
}
internal ECDiffieHellmanCngPublicKey(CngKey key) : base(key.Export(CngKeyBlobFormat.EccPublicBlob))
{
Contract.Requires(key != null && key.AlgorithmGroup == CngAlgorithmGroup.ECDiffieHellman);
Contract.Ensures(m_format != null);
m_format = CngKeyBlobFormat.EccPublicBlob;
//
// We need to make a copy of the key to prevent the situation where the ECDiffieHellmanCng algorithm
// object is disposed (this disposing its key) before the ECDiffieHellmanCngPublic key is disposed.
//
// Accessing the handle in partial trust is safe because we're not exposing it back out to user code
//
new SecurityPermission(SecurityPermissionFlag.UnmanagedCode).Assert();
// This looks odd, but .Handle returns a duplicate, so we need to dispose it
using (SafeNCryptKeyHandle importKey = key.Handle) {
m_key = CngKey.Open(importKey, key.IsEphemeral ? CngKeyHandleOpenOptions.EphemeralKey : CngKeyHandleOpenOptions.None);
}
CodeAccessPermission.RevertAssert();
}
public static CngKey Duplicate(CngKey key)
{
return(CngKey.Open(key.HandleNoDuplicate, key.IsEphemeral ? CngKeyHandleOpenOptions.EphemeralKey : CngKeyHandleOpenOptions.None));
}
