org.bouncycastle.cms

Class CMSEnvelopedDataParser

Known Direct Subclasses:
SMIMEEnvelopedParser

public class CMSEnvelopedDataParser
extends CMSContentInfoParser

Parsing class for an CMS Enveloped Data object from an input stream.

Note: that because we are in a streaming mode only one recipient can be tried and it is important that the methods on the parser are called in the appropriate order.

Example of use - assuming the first recipient matches the private key we have.

      CMSEnvelopedDataParser     ep = new CMSEnvelopedDataParser(inputStream);

      RecipientInformationStore  recipients = ep.getRecipientInfos();

      Collection  c = recipients.getRecipients();
      Iterator    it = c.iterator();
      
      if (it.hasNext())
      {
          RecipientInformation   recipient = (RecipientInformation)it.next();

          CMSTypedStream recData = recipient.getContentStream(privateKey, "BC");
          
          processDataStream(recData.getContentStream());
      }
  
Note: this class does not introduce buffering - if you are processing large files you should create the parser with:
          CMSEnvelopedDataParser     ep = new CMSEnvelopedDataParser(new BufferedInputStream(inputStream, bufSize));
  
where bufSize is a suitably large buffer size.

Field Summary

Fields inherited from class org.bouncycastle.cms.CMSContentInfoParser

_contentInfo, _data

Constructor Summary

CMSEnvelopedDataParser(InputStream envelopedData)
CMSEnvelopedDataParser(byte[] envelopedData)

Method Summary

String
getEncryptionAlgOID()
return the object identifier for the content encryption algorithm.
byte[]
getEncryptionAlgParams()
return the ASN.1 encoded encryption algorithm parameters, or null if there aren't any.
AlgorithmParameters
getEncryptionAlgorithmParameters(String provider)
Return an AlgorithmParameters object giving the encryption parameters used to encrypt the message content.
RecipientInformationStore
getRecipientInfos()
return a store of the intended recipients for this message
AttributeTable
getUnprotectedAttributes()
return a table of the unprotected attributes indexed by the OID of the attribute.

Methods inherited from class org.bouncycastle.cms.CMSContentInfoParser

close

Constructor Details

CMSEnvelopedDataParser

public CMSEnvelopedDataParser(InputStream envelopedData)
            throws CMSException,
                   IOException

CMSEnvelopedDataParser

public CMSEnvelopedDataParser(byte[] envelopedData)
            throws CMSException,
                   IOException

Method Details

getEncryptionAlgOID

public String getEncryptionAlgOID()
return the object identifier for the content encryption algorithm.

getEncryptionAlgParams

public byte[] getEncryptionAlgParams()
return the ASN.1 encoded encryption algorithm parameters, or null if there aren't any.

getEncryptionAlgorithmParameters

public AlgorithmParameters getEncryptionAlgorithmParameters(String provider)
            throws CMSException,
                   NoSuchProviderException
Return an AlgorithmParameters object giving the encryption parameters used to encrypt the message content.
Parameters:
provider - the provider to generate the parameters for.
Returns:
the parameters object, null if there is not one.
Throws:
CMSException - if the algorithm cannot be found, or the parameters can't be parsed.

getRecipientInfos

public RecipientInformationStore getRecipientInfos()
return a store of the intended recipients for this message

getUnprotectedAttributes

public AttributeTable getUnprotectedAttributes()
            throws IOException
return a table of the unprotected attributes indexed by the OID of the attribute.