/**
* base constructor
*
* @param signedContent the content that was signed.
* @param sigData the signature object.
*/
public CmsSignedDataParser(
CmsTypedStream signedContent,
Stream sigData)
: base(sigData)
{
try
{
this._signedContent = signedContent;
this._signedData = SignedDataParser.GetInstance(this.contentInfo.GetContent(Asn1Tags.Sequence));
this._digests = Platform.CreateHashtable();
this._digestOids = new HashSet();
Asn1SetParser digAlgs = _signedData.GetDigestAlgorithms();
IAsn1Convertible o;
while ((o = digAlgs.ReadObject()) != null)
{
AlgorithmIdentifier id = AlgorithmIdentifier.GetInstance(o.ToAsn1Object());
try
{
string digestOid = id.ObjectID.Id;
string digestName = Helper.GetDigestAlgName(digestOid);
if (!this._digests.Contains(digestName))
{
this._digests[digestName] = Helper.GetDigestInstance(digestName);
this._digestOids.Add(digestOid);
}
}
catch (SecurityUtilityException)
{
// TODO Should do something other than ignore it
}
}
//
// If the message is simply a certificate chain message GetContent() may return null.
//
ContentInfoParser cont = _signedData.GetEncapContentInfo();
Asn1OctetStringParser octs = (Asn1OctetStringParser)
cont.GetContent(Asn1Tags.OctetString);
if (octs != null)
{
CmsTypedStream ctStr = new CmsTypedStream(
cont.ContentType.Id, octs.GetOctetStream());
if (_signedContent == null)
{
this._signedContent = ctStr;
}
else
{
//
// content passed in, need to read past empty encapsulated content info object if present
//
ctStr.Drain();
}
}
_signedContentType = _signedContent == null
? cont.ContentType
: new DerObjectIdentifier(_signedContent.ContentType);
}
catch (IOException e)
{
throw new CmsException("io exception: " + e.Message, e);
}
if (_digests.Count < 1)
{
throw new CmsException("no digests could be created for message.");
}
}
