/**
* Fetches the signature time-stamp attributes from a SignerInformation object.
* Checks that the MessageImprint for each time-stamp matches the signature field.
* (see RFC 3161 Appendix A).
*
* @param signerInfo a SignerInformation to search for time-stamps
* @return a collection of TimeStampToken objects
* @throws TSPValidationException
*/
public static ICollection GetSignatureTimestamps(
SignerInformation signerInfo)
{
IList timestamps = Platform.CreateArrayList();
Asn1.Cms.AttributeTable unsignedAttrs = signerInfo.UnsignedAttributes;
if (unsignedAttrs != null)
{
foreach (Asn1.Cms.Attribute tsAttr in unsignedAttrs.GetAll(
PkcsObjectIdentifiers.IdAASignatureTimeStampToken))
{
foreach (Asn1Encodable asn1 in tsAttr.AttrValues)
{
try
{
Asn1.Cms.ContentInfo contentInfo = Asn1.Cms.ContentInfo.GetInstance(
asn1.ToAsn1Object());
TimeStampToken timeStampToken = new TimeStampToken(contentInfo);
TimeStampTokenInfo tstInfo = timeStampToken.TimeStampInfo;
byte[] expectedDigest = DigestUtilities.CalculateDigest(
GetDigestAlgName(tstInfo.MessageImprintAlgOid),
signerInfo.GetSignature());
if (!Arrays.ConstantTimeAreEqual(expectedDigest, tstInfo.GetMessageImprintDigest()))
throw new TspValidationException("Incorrect digest in message imprint");
timestamps.Add(timeStampToken);
}
catch (SecurityUtilityException)
{
throw new TspValidationException("Unknown hash algorithm specified in timestamp");
}
catch (Exception)
{
throw new TspValidationException("Timestamp could not be parsed");
}
}
}
}
return timestamps;
}
/**
* generate a set of one or more SignerInformation objects representing counter signatures on
* the passed in SignerInformation object.
*
* @param signer the signer to be countersigned
* @param sigProvider the provider to be used for counter signing.
* @return a store containing the signers.
*/
public SignerInformationStore GenerateCounterSigners(SignerInformation signer)
{
return(Generate(null, new CmsProcessableByteArray(signer.GetSignature()), false).GetSignerInfos());
}
internal virtual void AddSignerCallback(
SignerInformation si)
{
}
public TimeStampToken(
CmsSignedData signedData)
{
this.tsToken = signedData;
if (!this.tsToken.SignedContentType.Equals(PkcsObjectIdentifiers.IdCTTstInfo))
{
throw new TspValidationException("ContentInfo object not for a time stamp.");
}
ICollection signers = tsToken.GetSignerInfos().GetSigners();
if (signers.Count != 1)
{
throw new ArgumentException("Time-stamp token signed by "
+ signers.Count
+ " signers, but it must contain just the TSA signature.");
}
IEnumerator signerEnum = signers.GetEnumerator();
signerEnum.MoveNext();
tsaSignerInfo = (SignerInformation) signerEnum.Current;
try
{
CmsProcessable content = tsToken.SignedContent;
MemoryStream bOut = new MemoryStream();
content.Write(bOut);
this.tstInfo = new TimeStampTokenInfo(
TstInfo.GetInstance(
Asn1Object.FromByteArray(bOut.ToArray())));
Asn1.Cms.Attribute attr = tsaSignerInfo.SignedAttributes[
PkcsObjectIdentifiers.IdAASigningCertificate];
// if (attr == null)
// {
// throw new TspValidationException(
// "no signing certificate attribute found, time stamp invalid.");
// }
//
// SigningCertificate signCert = SigningCertificate.GetInstance(
// attr.AttrValues[0]);
//
// this.certID = EssCertID.GetInstance(signCert.GetCerts()[0]);
if (attr != null)
{
SigningCertificate signCert = SigningCertificate.GetInstance(attr.AttrValues[0]);
this.certID = new CertID(EssCertID.GetInstance(signCert.GetCerts()[0]));
}
else
{
attr = tsaSignerInfo.SignedAttributes[PkcsObjectIdentifiers.IdAASigningCertificateV2];
if (attr == null)
throw new TspValidationException("no signing certificate attribute found, time stamp invalid.");
SigningCertificateV2 signCertV2 = SigningCertificateV2.GetInstance(attr.AttrValues[0]);
this.certID = new CertID(EssCertIDv2.GetInstance(signCertV2.GetCerts()[0]));
}
}
catch (CmsException e)
{
throw new TspException(e.Message, e.InnerException);
}
}
/**
* 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);
}
/**
* Return a signer information object with the passed in unsigned
* attributes replacing the ones that are current associated with
* the object passed in.
*
* @param signerInformation the signerInfo to be used as the basis.
* @param unsignedAttributes the unsigned attributes to add.
* @return a copy of the original SignerInformationObject with the changed attributes.
*/
public static SignerInformation ReplaceUnsignedAttributes(
SignerInformation signerInformation,
Asn1.Cms.AttributeTable unsignedAttributes)
{
SignerInfo sInfo = signerInformation.info;
Asn1Set unsignedAttr = null;
if (unsignedAttributes != null)
{
unsignedAttr = new DerSet(unsignedAttributes.ToAsn1EncodableVector());
}
return new SignerInformation(
new SignerInfo(
sInfo.SignerID,
sInfo.DigestAlgorithm,
sInfo.AuthenticatedAttributes,
sInfo.DigestEncryptionAlgorithm,
sInfo.EncryptedDigest,
unsignedAttr),
signerInformation.contentType,
signerInformation.content,
null);
}
internal override void AddSignerCallback(SignerInformation si)
{
// FIXME If there were parameters in si.DigestAlgorithmID.Parameters, they are lost
// NB: Would need to call FixAlgID on the DigestAlgorithmID
// For precalculated signers, just need to register the algorithm, not configure a digest
RegisterDigestOid(si.DigestAlgorithmID.ObjectID.Id);
}
internal virtual void AddSignerCallback(
SignerInformation si)
{
}
/**
* generate a set of one or more SignerInformation objects representing counter signatures on
* the passed in SignerInformation object.
*
* @param signer the signer to be countersigned
* @param sigProvider the provider to be used for counter signing.
* @return a store containing the signers.
*/
public SignerInformationStore GenerateCounterSigners(SignerInformation signer)
{
return Generate(null, new CmsProcessableByteArray(signer.GetSignature()), false).GetSignerInfos();
}
