org.bouncycastle.cms

Class CMSAuthenticatedDataParser

java.lang.Object

org.bouncycastle.cms.CMSContentInfoParser

org.bouncycastle.cms.CMSAuthenticatedDataParser

public class CMSAuthenticatedDataParser
extends CMSContentInfoParser

Parsing class for an CMS Authenticated 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.

      CMSAuthenticatedDataParser     ad = new CMSAuthenticatedDataParser(inputStream);

      RecipientInformationStore  recipients = ad.getRecipientInfos();

      Collection  c = recipients.getRecipients();
      Iterator    it = c.iterator();

      if (it.hasNext())
      {
          RecipientInformation   recipient = (RecipientInformation)it.next();

          CMSTypedStream recData = recipient.getContentStream(new JceKeyTransAuthenticatedRecipient(privateKey).setProvider("BC"));

          processDataStream(recData.getContentStream());

          if (!Arrays.equals(ad.getMac(), recipient.getMac())
          {
              System.err.println("Data corrupted!!!!");
          }
      }
  

Note: this class does not introduce buffering - if you are processing large files you should create the parser with:

          CMSAuthenticatedDataParser     ep = new CMSAuthenticatedDataParser(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

Constructors

Constructor and Description
CMSAuthenticatedDataParser(byte[] envelopedData)
CMSAuthenticatedDataParser(byte[] envelopedData, DigestCalculatorProvider digestCalculatorProvider)
CMSAuthenticatedDataParser(InputStream envelopedData)
CMSAuthenticatedDataParser(InputStream envelopedData, DigestCalculatorProvider digestCalculatorProvider)

Method Summary

Methods

Modifier and Type	Method and Description
org.bouncycastle.asn1.cms.AttributeTable	getAuthAttrs() return a table of the unauthenticated attributes indexed by the OID of the attribute.
byte[]	getContentDigest() This will only be valid after the content has been read.
byte[]	getMac()
String	getMacAlgOID() return the object identifier for the mac algorithm.
AlgorithmParameters	getMacAlgorithmParameters(Provider provider) Return an AlgorithmParameters object giving the encryption parameters used to encrypt the message content.
AlgorithmParameters	getMacAlgorithmParameters(String provider) Return an AlgorithmParameters object giving the encryption parameters used to encrypt the message content.
byte[]	getMacAlgParams() return the ASN.1 encoded encryption algorithm parameters, or null if there aren't any.
RecipientInformationStore	getRecipientInfos() return a store of the intended recipients for this message
org.bouncycastle.asn1.cms.AttributeTable	getUnauthAttrs() return a table of the unauthenticated attributes indexed by the OID of the attribute.

Methods inherited from class org.bouncycastle.cms.CMSContentInfoParser

close

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

CMSAuthenticatedDataParser

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

Throws:

CMSException

IOException

CMSAuthenticatedDataParser

public CMSAuthenticatedDataParser(byte[] envelopedData,
                          DigestCalculatorProvider digestCalculatorProvider)
                           throws CMSException,
                                  IOException

Throws:

CMSException

IOException

CMSAuthenticatedDataParser

public CMSAuthenticatedDataParser(InputStream envelopedData)
                           throws CMSException,
                                  IOException

Throws:

CMSException

IOException

CMSAuthenticatedDataParser

public CMSAuthenticatedDataParser(InputStream envelopedData,
                          DigestCalculatorProvider digestCalculatorProvider)
                           throws CMSException,
                                  IOException

Throws:

CMSException

IOException

Method Detail

getMacAlgOID

public String getMacAlgOID()

return the object identifier for the mac algorithm.

getMacAlgParams

public byte[] getMacAlgParams()

return the ASN.1 encoded encryption algorithm parameters, or null if there aren't any.

getMacAlgorithmParameters

public AlgorithmParameters getMacAlgorithmParameters(String provider)
                                              throws CMSException,
                                                     NoSuchProviderException

Return an AlgorithmParameters object giving the encryption parameters used to encrypt the message content.

Parameters:

provider - the name of 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.

NoSuchProviderException - if the provider cannot be found.

getMacAlgorithmParameters

public AlgorithmParameters getMacAlgorithmParameters(Provider provider)
                                              throws CMSException

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

getMac

public byte[] getMac()
              throws IOException

Throws:

IOException

getAuthAttrs

public org.bouncycastle.asn1.cms.AttributeTable getAuthAttrs()
                                                      throws IOException

return a table of the unauthenticated attributes indexed by the OID of the attribute.

Throws:

IOException

getUnauthAttrs

public org.bouncycastle.asn1.cms.AttributeTable getUnauthAttrs()
                                                        throws IOException

return a table of the unauthenticated attributes indexed by the OID of the attribute.

Throws:

IOException

getContentDigest

public byte[] getContentDigest()

This will only be valid after the content has been read.

Returns:

the contents of the messageDigest attribute, if available. Null if not present.