/**
* Return the number of bytes or characters required to contain the
* passed in object if it is PEM encoded.
*
* @param obj pem object to be output
* @return an estimate of the number of bytes
*/
public int GetOutputSize(PemObject obj)
{
// BEGIN and END boundaries.
int size = (2 * (obj.Type.Length + 10 + nlLength)) + 6 + 4;
if (obj.Headers.Count > 0)
{
foreach (PemHeader header in obj.Headers)
{
size += header.Name.Length + ": ".Length + header.Value.Length + nlLength;
}
size += nlLength;
}
// base64 encoding
int dataLen = ((obj.Content.Length + 2) / 3) * 4;
size += dataLen + (((dataLen + LineLength - 1) / LineLength) * nlLength);
return size;
}
/**
* Read a Key Pair
*/
private object ReadPrivateKey(PemObject pemObject)
{
//
// extract the key
//
Debug.Assert(pemObject.Type.EndsWith("PRIVATE KEY"));
string type = pemObject.Type.Substring(0, pemObject.Type.Length - "PRIVATE KEY".Length).Trim();
byte[] keyBytes = pemObject.Content;
IDictionary fields = Platform.CreateHashtable();
foreach (PemHeader header in pemObject.Headers)
{
fields[header.Name] = header.Value;
}
string procType = (string) fields["Proc-Type"];
if (procType == "4,ENCRYPTED")
{
if (pFinder == null)
throw new PasswordException("No password finder specified, but a password is required");
char[] password = pFinder.GetPassword();
if (password == null)
throw new PasswordException("Password is null, but a password is required");
string dekInfo = (string) fields["DEK-Info"];
string[] tknz = dekInfo.Split(',');
string dekAlgName = tknz[0].Trim();
byte[] iv = Hex.Decode(tknz[1].Trim());
keyBytes = PemUtilities.Crypt(false, keyBytes, password, dekAlgName, iv);
}
try
{
AsymmetricKeyParameter pubSpec, privSpec;
Asn1Sequence seq = (Asn1Sequence) Asn1Object.FromByteArray(keyBytes);
switch (type)
{
case "RSA":
{
if (seq.Count != 9)
throw new PemException("malformed sequence in RSA private key");
RsaPrivateKeyStructure rsa = new RsaPrivateKeyStructure(seq);
pubSpec = new RsaKeyParameters(false, rsa.Modulus, rsa.PublicExponent);
privSpec = new RsaPrivateCrtKeyParameters(
rsa.Modulus, rsa.PublicExponent, rsa.PrivateExponent,
rsa.Prime1, rsa.Prime2, rsa.Exponent1, rsa.Exponent2,
rsa.Coefficient);
break;
}
case "DSA":
{
if (seq.Count != 6)
throw new PemException("malformed sequence in DSA private key");
// TODO Create an ASN1 object somewhere for this?
//DerInteger v = (DerInteger)seq[0];
DerInteger p = (DerInteger)seq[1];
DerInteger q = (DerInteger)seq[2];
DerInteger g = (DerInteger)seq[3];
DerInteger y = (DerInteger)seq[4];
DerInteger x = (DerInteger)seq[5];
DsaParameters parameters = new DsaParameters(p.Value, q.Value, g.Value);
privSpec = new DsaPrivateKeyParameters(x.Value, parameters);
pubSpec = new DsaPublicKeyParameters(y.Value, parameters);
break;
}
case "EC":
{
ECPrivateKeyStructure pKey = new ECPrivateKeyStructure(seq);
AlgorithmIdentifier algId = new AlgorithmIdentifier(
X9ObjectIdentifiers.IdECPublicKey, pKey.GetParameters());
PrivateKeyInfo privInfo = new PrivateKeyInfo(algId, pKey.ToAsn1Object());
// TODO Are the keys returned here ECDSA, as Java version forces?
privSpec = PrivateKeyFactory.CreateKey(privInfo);
DerBitString pubKey = pKey.GetPublicKey();
if (pubKey != null)
{
SubjectPublicKeyInfo pubInfo = new SubjectPublicKeyInfo(algId, pubKey.GetBytes());
// TODO Are the keys returned here ECDSA, as Java version forces?
pubSpec = PublicKeyFactory.CreateKey(pubInfo);
}
else
{
pubSpec = ECKeyPairGenerator.GetCorrespondingPublicKey(
(ECPrivateKeyParameters)privSpec);
}
break;
}
case "ENCRYPTED":
{
char[] password = pFinder.GetPassword();
if (password == null)
throw new PasswordException("Password is null, but a password is required");
return PrivateKeyFactory.DecryptKey(password, EncryptedPrivateKeyInfo.GetInstance(seq));
}
case "":
{
return PrivateKeyFactory.CreateKey(PrivateKeyInfo.GetInstance(seq));
}
default:
throw new ArgumentException("Unknown key type: " + type, "type");
}
return new AsymmetricCipherKeyPair(pubSpec, privSpec);
}
catch (IOException e)
{
throw e;
}
catch (Exception e)
{
throw new PemException(
"problem creating " + type + " private key: " + e.ToString());
}
}
/**
* Reads in a PKCS7 object. This returns a ContentInfo object suitable for use with the CMS
* API.
*
* @return the X509Certificate
* @throws IOException if an I/O error occured
*/
// TODO Consider returning Asn1.Pkcs.ContentInfo
private Asn1.Cms.ContentInfo ReadPkcs7(PemObject pemObject)
{
try
{
return Asn1.Cms.ContentInfo.GetInstance(
Asn1Object.FromByteArray(pemObject.Content));
}
catch (Exception e)
{
throw new PemException("problem parsing PKCS7 object: " + e.ToString());
}
}
/**
* Reads in a X509 Attribute Certificate.
*
* @return the X509 Attribute Certificate
* @throws IOException if an I/O error occured
*/
private IX509AttributeCertificate ReadAttributeCertificate(PemObject pemObject)
{
return new X509V2AttributeCertificate(pemObject.Content);
}
/**
* Reads in a PKCS10 certification request.
*
* @return the certificate request.
* @throws IOException if an I/O error occured
*/
private Pkcs10CertificationRequest ReadCertificateRequest(PemObject pemObject)
{
try
{
return new Pkcs10CertificationRequest(pemObject.Content);
}
catch (Exception e)
{
throw new PemException("problem parsing cert: " + e.ToString());
}
}
/**
* Reads in a X509CRL.
*
* @return the X509Certificate
* @throws IOException if an I/O error occured
*/
private X509Crl ReadCrl(PemObject pemObject)
{
try
{
return new X509CrlParser().ReadCrl(pemObject.Content);
}
catch (Exception e)
{
throw new PemException("problem parsing cert: " + e.ToString());
}
}
private AsymmetricKeyParameter ReadPublicKey(PemObject pemObject)
{
return PublicKeyFactory.CreateKey(pemObject.Content);
}
private AsymmetricKeyParameter ReadRsaPublicKey(PemObject pemObject)
{
RsaPublicKeyStructure rsaPubStructure = RsaPublicKeyStructure.GetInstance(
Asn1Object.FromByteArray(pemObject.Content));
return new RsaKeyParameters(
false, // not private
rsaPubStructure.Modulus,
rsaPubStructure.PublicExponent);
}
