public DHAlgo(ASN1Tag tag)
{
var paramId = new ByteArray(tag.CheckTag(0x30).Child(2, 0x02).Data).ToUInt;
if (paramId != 2)
{
throw new Exception("Parametri di default : " + paramId.ToString() + " non supportati");
}
Prime = StandardDHParam2Prime;
Group = StandardDHParam2Group;
Order = StandardDHParam2Order;
DG14Tag = tag;
}
public CVCert(byte[] data)
{
ASN1Tag cert = ASN1Tag.Parse(data, false);
cert.CheckTag(0x7F21);
ASN1Tag certContent = cert.Child(0, 0x7F4E);
Signature = cert.Child(1, 0x5F37).Data;
Version = (int)new ByteArray(certContent.Child(0, 0x5F29).Data).ToUInt;
Issuer = new ByteArray(certContent.Child(1, 0x42).Data).ToASCII;
Name = new ByteArray(certContent.Child(3, 0x5F20).Data).ToASCII;
ValidFrom = certContent.Child(5, 0x5F25).Data;
Expire = certContent.Child(6, 0x5F24).Data;
ASN1Tag PubKey = certContent.Child(2, 0x7F49);
PubKeyAlgoOID = PubKey.Child(0, 0x06).Data;
PubKeyModule = PubKey.Child(1, 0x81).Data;
PubKeyExponent = PubKey.Child(2, 0x82).Data;
ASN1Tag certTemplate = certContent.Child(4, 0x7F4C);
CertificateTemplateOID = certTemplate.Child(0, 0x06).Data;
CertificateTemplateValue = certTemplate.Child(1, 0x53).Data;
RawCert = new ByteArray(data).Left((int)cert.EndPos);
}
bool IssuedBy(X509Certificate2 cert, X509Certificate2 issuer)
{
try
{
if (!new ByteArray(cert.IssuerName.RawData).IsEqual(issuer.SubjectName.RawData))
{
// verifico attributo per attributo
var IssuerTag = ASN1Tag.Parse(cert.IssuerName.RawData, false);
var SubjectTag = ASN1Tag.Parse(issuer.SubjectName.RawData, false);
Dictionary <string, byte[]> IssuerComponents = new Dictionary <string, byte[]>();
Dictionary <string, byte[]> SubjectComponents = new Dictionary <string, byte[]>();
foreach (var c in IssuerTag.children)
{
var comp = c.Child(0);
IssuerComponents[ASN1ObjIdDisplay.singleton.contentString(comp.Child(0))] = comp.Child(1).Data;
}
foreach (var c in SubjectTag.children)
{
var comp = c.Child(0);
SubjectComponents[ASN1ObjIdDisplay.singleton.contentString(comp.Child(0))] = comp.Child(1).Data;
}
string[] keys = new string[IssuerComponents.Count];
IssuerComponents.Keys.CopyTo(keys, 0);
foreach (var o in keys)
{
if (!SubjectComponents.ContainsKey(o))
{
return(false);
}
var sub = UTF8Encoding.UTF8.GetString(SubjectComponents[o]);
var iss = UTF8Encoding.UTF8.GetString(IssuerComponents[o]);
if (sub != iss)
{
return(false);
}
IssuerComponents.Remove(o);
SubjectComponents.Remove(o);
}
if (IssuerComponents.Count > 0 || SubjectComponents.Count > 0)
{
return(false);
}
}
var akiExt = cert.Extensions["2.5.29.35"];
if (akiExt != null)
{
ASN1Tag akiTag = ASN1Tag.Parse(akiExt.RawData, false);
var aki = akiTag.CheckTag(0x30);
var aki2Tag = ASN1Tag.Parse(aki.Data, false);
var akiData = aki2Tag.CheckTag(0x80).Data;
var skiExt = issuer.Extensions["2.5.29.14"] as X509SubjectKeyIdentifierExtension;
if (skiExt == null)
{
return(false);
}
if (skiExt.SubjectKeyIdentifier != HexDump(akiData))
{
return(false);
}
}
// verifico che la firma torni
var certTag = ASN1Tag.Parse(cert.RawData, false);
var signature = certTag.Child(2, 0x03).Data;
var keyTag = ASN1Tag.Parse(issuer.PublicKey.EncodedKeyValue.RawData);
var module = keyTag.Child(0, 2).Data;
var pubExp = keyTag.Child(1, 2).Data;
var rsa = new RSA();
var decSignature = ByteArray.RemoveBT1(rsa.RawRsa(module, pubExp, signature));
byte[] signedHash = null, certHash = null;
var toHash = new ByteArray(cert.RawData).Sub((int)certTag.children[0].StartPos, (int)(certTag.children[0].EndPos - certTag.children[0].StartPos));
if (cert.SignatureAlgorithm.Value == "1.2.840.113549.1.1.5")
{
signedHash = rsa.RemoveSha1(decSignature);
certHash = new SHA1().Digest(toHash);
}
else if (cert.SignatureAlgorithm.FriendlyName == "1.2.840.113549.1.1.11")
{
signedHash = rsa.RemoveSha256(decSignature);
certHash = new SHA256().Digest(toHash);
}
else
{
throw new Exception("Algoritmo non supportato");
}
if (!new ByteArray(signedHash).IsEqual(certHash))
{
return(false);
}
return(true);
}
catch { }
return(false);
}
