private CmsSignedData(
			CmsSignedData c)
		{
			this.signedData = c.signedData;
			this.contentInfo = c.contentInfo;
			this.signedContent = c.signedContent;
			this.signerInfoStore = c.signerInfoStore;
		}
        /**
        * generate a signed object that for a CMS Signed Data
        * object  - if encapsulate is true a copy
        * of the message will be included in the signature. The content type
        * is set according to the OID represented by the string signedContentType.
        */

        public CmsSignedData Generate(string signedContentType, // FIXME Avoid accessing more than once to support CmsProcessableInputStream
            CmsProcessable content, bool encapsulate)
        {
            var digestAlgs = new Asn1EncodableVector();
            var signerInfos = new Asn1EncodableVector();

            _digests.Clear(); // clear the current preserved digest state

            //
            // add the precalculated SignerInfo objects.
            //
            foreach (SignerInformation signer in _signers)
            {
                digestAlgs.Add(Helper.FixAlgID(signer.DigestAlgorithmID));

                // TODO Verify the content type and calculated digest match the precalculated SignerInfo
                signerInfos.Add(signer.ToSignerInfo());
            }

            //
            // add the SignerInfo objects
            //
            bool isCounterSignature = (signedContentType == null);

            DerObjectIdentifier contentTypeOid = isCounterSignature ? null : new DerObjectIdentifier(signedContentType);

            foreach (SignerInf signer in _signerInfs)
            {
                try
                {
                    digestAlgs.Add(signer.DigestAlgorithmID);
                    signerInfos.Add(signer.ToSignerInfo(contentTypeOid, content, rand));
                }
                catch (IOException e)
                {
                    throw new CmsException("encoding error.", e);
                }
                catch (InvalidKeyException e)
                {
                    throw new CmsException("key inappropriate for signature.", e);
                }
                catch (SignatureException e)
                {
                    throw new CmsException("error creating signature.", e);
                }
                catch (CertificateEncodingException e)
                {
                    throw new CmsException("error creating sid.", e);
                }
            }

            Asn1Set certificates = null;

            if (_certs.Count != 0)
            {
                certificates = CmsUtilities.CreateBerSetFromList(_certs);
            }

            Asn1Set certrevlist = null;

            if (_crls.Count != 0)
            {
                certrevlist = CmsUtilities.CreateBerSetFromList(_crls);
            }

            Asn1OctetString octs = null;
            if (encapsulate)
            {
                var bOut = new MemoryStream();
                if (content != null)
                {
                    try
                    {
                        content.Write(bOut);
                    }
                    catch (IOException e)
                    {
                        throw new CmsException("encapsulation error.", e);
                    }
                }
                octs = new BerOctetString(bOut.ToArray());
            }

            var encInfo = new ContentInfo(contentTypeOid, octs);

            var sd = new SignedData(new DerSet(digestAlgs), encInfo, certificates, certrevlist, new DerSet(signerInfos));

            var contentInfo = new ContentInfo(CmsObjectIdentifiers.SignedData, sd);

            return new CmsSignedData(content, contentInfo);
        }
		public CmsSignedData(
			IDictionary	hashes,
			ContentInfo	sigData)
		{
			this.hashes = hashes;
			this.contentInfo = sigData;
			this.signedData = SignedData.GetInstance(contentInfo.Content);
		}
		public CmsSignedData(
			ContentInfo sigData)
		{
			this.contentInfo = sigData;
			this.signedData = SignedData.GetInstance(contentInfo.Content);

			//
			// this can happen if the signed message is sent simply to send a
			// certificate chain.
			//
			if (signedData.EncapContentInfo.Content != null)
			{
				this.signedContent = new CmsProcessableByteArray(
					((Asn1OctetString)(signedData.EncapContentInfo.Content)).GetOctets());
			}
//			else
//			{
//				this.signedContent = null;
//			}
		}
		public CmsSignedData(
			CmsProcessable  signedContent,
			ContentInfo     sigData)
		{
			this.signedContent = signedContent;
			this.contentInfo = sigData;
			this.signedData = SignedData.GetInstance(contentInfo.Content);
		}