internal static void ReadSubjectPublicKeyInfo(this DerSequenceReader keyInfo, ref DSAParameters parameters)
{
// SubjectPublicKeyInfo::= SEQUENCE {
// algorithm AlgorithmIdentifier,
// subjectPublicKey BIT STRING }
DerSequenceReader algorithm = keyInfo.ReadSequence();
string algorithmOid = algorithm.ReadOidAsString();
// EC Public Key
if (algorithmOid != s_idDsa.Value)
{
throw new CryptographicException();
}
// Dss-Parms ::= SEQUENCE {
// p INTEGER,
// q INTEGER,
// g INTEGER
// }
DerSequenceReader algParameters = algorithm.ReadSequence();
byte[] publicKeyBlob = keyInfo.ReadBitString();
// We don't care about the rest of the blob here, but it's expected to not exist.
ReadSubjectPublicKeyInfo(algParameters, publicKeyBlob, ref parameters);
}
internal static void ReadSubjectPublicKeyInfo(this DerSequenceReader keyInfo, ref ECParameters parameters)
{
// SubjectPublicKeyInfo::= SEQUENCE {
// algorithm AlgorithmIdentifier,
// subjectPublicKey BIT STRING }
DerSequenceReader algorithm = keyInfo.ReadSequence();
string algorithmOid = algorithm.ReadOidAsString();
// EC Public Key
if (algorithmOid != s_idEcPublicKey.Value)
{
throw new CryptographicException();
}
if (algorithm.PeekTag() != (int)DerSequenceReader.DerTag.ObjectIdentifier)
{
throw new PlatformNotSupportedException(SR.Cryptography_ECC_NamedCurvesOnly);
}
parameters.Curve = ECCurve.CreateFromValue(algorithm.ReadOidAsString());
byte[] encodedPoint = keyInfo.ReadBitString();
ReadEncodedPoint(encodedPoint, ref parameters);
// We don't care about the rest of the blob here, but it's expected to not exist.
}
internal static void ReadSubjectPublicKeyInfo(this DerSequenceReader keyInfo, ref RSAParameters parameters)
{
// SubjectPublicKeyInfo::= SEQUENCE {
// algorithm AlgorithmIdentifier,
// subjectPublicKey BIT STRING }
DerSequenceReader algorithm = keyInfo.ReadSequence();
string algorithmOid = algorithm.ReadOidAsString();
if (algorithmOid != RsaOid)
{
throw new CryptographicException();
}
byte[] subjectPublicKeyBytes = keyInfo.ReadBitString();
DerSequenceReader subjectPublicKey = new DerSequenceReader(subjectPublicKeyBytes);
subjectPublicKey.ReadPkcs1PublicBlob(ref parameters);
}
internal static void ReadPkcs8Blob(this DerSequenceReader reader, ref ECParameters parameters)
{
// OneAsymmetricKey ::= SEQUENCE {
// version Version,
// privateKeyAlgorithm PrivateKeyAlgorithmIdentifier,
// privateKey PrivateKey,
// attributes [0] Attributes OPTIONAL,
// ...,
// [[2: publicKey [1] PublicKey OPTIONAL ]],
// ...
// }
//
// PrivateKeyInfo ::= OneAsymmetricKey
//
// PrivateKey ::= OCTET STRING
int version = reader.ReadInteger();
// We understand both version 0 and 1 formats,
// which are now known as v1 and v2, respectively.
if (version > 1)
{
throw new CryptographicException();
}
{
// Ensure we're reading EC Public Key (well, Private, but the OID says Public)
DerSequenceReader algorithm = reader.ReadSequence();
string algorithmOid = algorithm.ReadOidAsString();
if (algorithmOid != s_idEcPublicKey.Value)
{
throw new CryptographicException();
}
}
byte[] privateKeyBlob = reader.ReadOctetString();
try
{
// ECPrivateKey{CURVES:IOSet} ::= SEQUENCE {
// version INTEGER { ecPrivkeyVer1(1) } (ecPrivkeyVer1),
// privateKey OCTET STRING,
// parameters [0] Parameters{{IOSet}} OPTIONAL,
// publicKey [1] BIT STRING OPTIONAL
// }
DerSequenceReader keyReader = new DerSequenceReader(privateKeyBlob);
version = keyReader.ReadInteger();
// We understand the version 1 format
if (version > 1)
{
throw new CryptographicException();
}
parameters.D = keyReader.ReadOctetString();
// Check for context specific 0
const byte ConstructedContextSpecific =
DerSequenceReader.ContextSpecificTagFlag | DerSequenceReader.ConstructedFlag;
const byte ConstructedContextSpecific0 = (ConstructedContextSpecific | 0);
const byte ConstructedContextSpecific1 = (ConstructedContextSpecific | 1);
if (keyReader.PeekTag() != ConstructedContextSpecific0)
{
throw new CryptographicException();
}
// Parameters ::= CHOICE {
// ecParameters ECParameters,
// namedCurve CURVES.&id({ CurveNames}),
// implicitlyCA NULL
// }
DerSequenceReader parametersReader = keyReader.ReadSequence();
if (parametersReader.PeekTag() != (int)DerSequenceReader.DerTag.ObjectIdentifier)
{
throw new PlatformNotSupportedException(SR.Cryptography_ECC_NamedCurvesOnly);
}
parameters.Curve = ECCurve.CreateFromValue(parametersReader.ReadOidAsString());
// Check for context specific 1
if (keyReader.PeekTag() != ConstructedContextSpecific1)
{
throw new CryptographicException();
}
keyReader = keyReader.ReadSequence();
byte[] encodedPoint = keyReader.ReadBitString();
ReadEncodedPoint(encodedPoint, ref parameters);
// We don't care about the rest of the blob here, but it's expected to not exist.
}
finally
{
Array.Clear(privateKeyBlob, 0, privateKeyBlob.Length);
}
}
