/**
* Replace the signerinformation store associated with the passed
* in message contained in the stream original with the new one passed in.
* You would probably only want to do this if you wanted to change the unsigned
* attributes associated with a signer, or perhaps delete one.
* <p>
* The output stream is returned unclosed.
* </p>
* @param original the signed data stream to be used as a base.
* @param signerInformationStore the new signer information store to use.
* @param out the stream to Write the new signed data object to.
* @return out.
*/
public static Stream ReplaceSigners(
Stream original,
SignerInformationStore signerInformationStore,
Stream outStr)
{
// NB: SecureRandom would be ignored since using existing signatures only
CmsSignedDataStreamGenerator gen = new CmsSignedDataStreamGenerator();
CmsSignedDataParser parser = new CmsSignedDataParser(original);
// gen.AddDigests(parser.DigestOids);
gen.AddSigners(signerInformationStore);
CmsTypedStream signedContent = parser.GetSignedContent();
bool encapsulate = (signedContent != null);
Stream contentOut = gen.Open(outStr, parser.SignedContentType.Id, encapsulate);
if (encapsulate)
{
Streams.PipeAll(signedContent.ContentStream, contentOut);
}
gen.AddAttributeCertificates(parser.GetAttributeCertificates("Collection"));
gen.AddCertificates(parser.GetCertificates("Collection"));
gen.AddCrls(parser.GetCrls("Collection"));
// gen.AddSigners(parser.GetSignerInfos());
Platform.Dispose(contentOut);
return(outStr);
}
/**
* return the collection of signers that are associated with the
* signatures for the message.
*/
public SignerInformationStore GetSignerInfos()
{
if (signerInfoStore == null)
{
IList signerInfos = Platform.CreateArrayList();
Asn1Set s = signedData.SignerInfos;
foreach (object obj in s)
{
SignerInfo info = SignerInfo.GetInstance(obj);
DerObjectIdentifier contentType = signedData.EncapContentInfo.ContentType;
if (hashes == null)
{
signerInfos.Add(new SignerInformation(info, contentType, signedContent, null));
}
else
{
byte[] hash = (byte[])hashes[info.DigestAlgorithm.Algorithm.Id];
signerInfos.Add(new SignerInformation(info, contentType, null, new BaseDigestCalculator(hash)));
}
}
signerInfoStore = new SignerInformationStore(signerInfos);
}
return(signerInfoStore);
}
private CmsSignedData(
CmsSignedData c)
{
this.signedData = c.signedData;
this.contentInfo = c.contentInfo;
this.signedContent = c.signedContent;
this.signerInfoStore = c.signerInfoStore;
}
/**
* Add a store of precalculated signers to the generator.
*
* @param signerStore store of signers
*/
public void AddSigners(
SignerInformationStore signerStore)
{
foreach (SignerInformation o in signerStore.GetSigners())
{
_signers.Add(o);
AddSignerCallback(o);
}
}
/**
* Replace the signerinformation store associated with this
* CmsSignedData object with the new one passed in. You would
* probably only want to do this if you wanted to change the unsigned
* attributes associated with a signer, or perhaps delete one.
*
* @param signedData the signed data object to be used as a base.
* @param signerInformationStore the new signer information store to use.
* @return a new signed data object.
*/
public static CmsSignedData ReplaceSigners(
CmsSignedData signedData,
SignerInformationStore signerInformationStore)
{
//
// copy
//
CmsSignedData cms = new CmsSignedData(signedData);
//
// replace the store
//
cms.signerInfoStore = signerInformationStore;
//
// replace the signers in the SignedData object
//
Asn1EncodableVector digestAlgs = new Asn1EncodableVector();
Asn1EncodableVector vec = new Asn1EncodableVector();
foreach (SignerInformation signer in signerInformationStore.GetSigners())
{
digestAlgs.Add(Helper.FixAlgID(signer.DigestAlgorithmID));
vec.Add(signer.ToSignerInfo());
}
Asn1Set digests = new DerSet(digestAlgs);
Asn1Set signers = new DerSet(vec);
Asn1Sequence sD = (Asn1Sequence)signedData.signedData.ToAsn1Object();
//
// signers are the last item in the sequence.
//
vec = new Asn1EncodableVector(
sD[0], // version
digests);
for (int i = 2; i != sD.Count - 1; i++)
{
vec.Add(sD[i]);
}
vec.Add(signers);
cms.signedData = SignedData.GetInstance(new BerSequence(vec));
//
// replace the contentInfo with the new one
//
cms.contentInfo = new ContentInfo(cms.contentInfo.ContentType, cms.signedData);
return(cms);
}
/**
* return the collection of signers that are associated with the
* signatures for the message.
* @throws CmsException
*/
public SignerInformationStore GetSignerInfos()
{
if (_signerInfoStore == null)
{
PopulateCertCrlSets();
IList signerInfos = Platform.CreateArrayList();
IDictionary hashes = Platform.CreateHashtable();
foreach (object digestKey in _digests.Keys)
{
hashes[digestKey] = DigestUtilities.DoFinal(
(IDigest)_digests[digestKey]);
}
try
{
Asn1SetParser s = _signedData.GetSignerInfos();
IAsn1Convertible o;
while ((o = s.ReadObject()) != null)
{
SignerInfo info = SignerInfo.GetInstance(o.ToAsn1Object());
string digestName = Helper.GetDigestAlgName(
info.DigestAlgorithm.Algorithm.Id);
byte[] hash = (byte[])hashes[digestName];
signerInfos.Add(new SignerInformation(info, _signedContentType, null, new BaseDigestCalculator(hash)));
}
}
catch (IOException e)
{
throw new CmsException("io exception: " + e.Message, e);
}
_signerInfoStore = new SignerInformationStore(signerInfos);
}
return(_signerInfoStore);
}
/**
* Return a signer information object with passed in SignerInformationStore representing counter
* signatures attached as an unsigned attribute.
*
* @param signerInformation the signerInfo to be used as the basis.
* @param counterSigners signer info objects carrying counter signature.
* @return a copy of the original SignerInformationObject with the changed attributes.
*/
public static SignerInformation AddCounterSigners(
SignerInformation signerInformation,
SignerInformationStore counterSigners)
{
// TODO Perform checks from RFC 3852 11.4
SignerInfo sInfo = signerInformation.info;
Asn1.Cms.AttributeTable unsignedAttr = signerInformation.UnsignedAttributes;
Asn1EncodableVector v;
if (unsignedAttr != null)
{
v = unsignedAttr.ToAsn1EncodableVector();
}
else
{
v = new Asn1EncodableVector();
}
Asn1EncodableVector sigs = new Asn1EncodableVector();
foreach (SignerInformation sigInf in counterSigners.GetSigners())
{
sigs.Add(sigInf.ToSignerInfo());
}
v.Add(new Asn1.Cms.Attribute(CmsAttributes.CounterSignature, new DerSet(sigs)));
return(new SignerInformation(
new SignerInfo(
sInfo.SignerID,
sInfo.DigestAlgorithm,
sInfo.AuthenticatedAttributes,
sInfo.DigestEncryptionAlgorithm,
sInfo.EncryptedDigest,
new DerSet(v)),
signerInformation.contentType,
signerInformation.content,
null));
}
