public SymAlgorithms[] FindPreferedAlgorithms()
{
IEnumerator ieCertificates = this.alCertifications.GetEnumerator();
while (ieCertificates.MoveNext())
{
if (!(ieCertificates.Current is CertifiedUserID))
{
continue;
}
CertifiedUserID cuiID = (CertifiedUserID)ieCertificates.Current;
IEnumerator ieSignatures = cuiID.Certificates.GetEnumerator();
while (ieSignatures.MoveNext())
{
if (!(ieSignatures.Current is SignaturePacket))
{
continue;
}
SignaturePacket spCertificate = (SignaturePacket)ieSignatures.Current;
// look only at selfsignatures
if (spCertificate.KeyID != this.PrimaryKey.KeyID)
{
continue;
}
try {
SymAlgorithms[] saReturn = spCertificate.FindPreferedSymAlgorithms();
return(saReturn);
} catch (Exception) {}
}
}
throw new Exception("none found!");
}
private SymAlgorithms GetSymAlgorithmPreferences(TransportablePublicKey[] tpkKeys)
{
bool bCAST5 = true;
bool bAES256 = true;
bool bAES192 = true;
bool bAES128 = true;
for (int i = 0; i < tpkKeys.Length; i++)
{
TransportablePublicKey tpkKey = tpkKeys[i];
ulong lKeyID = tpkKey.PrimaryKey.KeyID;
IEnumerator ieCerts = tpkKey.Certifications.GetEnumerator();
while (ieCerts.MoveNext())
{
if (!(ieCerts.Current is CertifiedUserID))
{
continue;
}
CertifiedUserID cuiID = (CertifiedUserID)ieCerts.Current;
IEnumerator ieSigs = cuiID.Certificates.GetEnumerator();
while (ieSigs.MoveNext())
{
if (!(ieSigs.Current is SignaturePacket))
{
continue;
}
SignaturePacket spSig = (SignaturePacket)ieSigs.Current;
if ((spSig.Version == SignaturePacketVersionNumbers.v4) && (spSig.KeyID == lKeyID))
{
try {
bool bTmpCAST5 = false;
bool bTmpAES256 = false;
bool bTmpAES192 = false;
bool bTmpAES128 = false;
SymAlgorithms[] saThisKey = spSig.FindPreferedSymAlgorithms();
for (int j = 0; j < saThisKey.Length; j++)
{
if (saThisKey[j] == SymAlgorithms.AES128)
{
bTmpAES128 = true;
}
else if (saThisKey[j] == SymAlgorithms.AES192)
{
bTmpAES192 = true;
}
else if (saThisKey[j] == SymAlgorithms.AES256)
{
bTmpAES256 = true;
}
else if (saThisKey[j] == SymAlgorithms.CAST5)
{
bTmpCAST5 = true;
}
}
if (!bTmpCAST5)
{
bCAST5 = false;
}
if (!bTmpAES256)
{
bAES256 = false;
}
if (!bTmpAES192)
{
bAES192 = false;
}
if (!bTmpAES128)
{
bAES128 = false;
}
} catch (InvalidOperationException) {}
}
}
}
}
if (bAES256)
{
return(SymAlgorithms.AES256);
}
if (bAES192)
{
return(SymAlgorithms.AES192);
}
if (bAES128)
{
return(SymAlgorithms.AES128);
}
if (bCAST5)
{
return(SymAlgorithms.CAST5);
}
return(SymAlgorithms.Triple_DES);
}