AuthenticatedDataStream ("Entrust Authority Security Toolkit for the Java Platform")

java.lang.Object
- iaik.cms.AuthenticatedDataStream

All Implemented Interfaces:

EncodeListener, ContentStream, EOFListener, java.util.EventListener

Direct Known Subclasses:

AuthenticatedData
```
public class AuthenticatedDataStream
extends java.lang.Object
implements ContentStream, EncodeListener, EOFListener
```
This class represents the stream supporting implementation of the CMS AuthenticatedData type.
Each CMS content type is associated with a specific object identifier, derived from:
```
 pkcs-9 OBJECT IDENTIFIER ::=
   { iso(1) member-body(2) US(840) rsadsi(113549)
       pkcs(1) 9 }
 
```
The object identifier for the AuthenticatedData content type is defined as:
id-ct-authData OBJECT IDENTIFIER ::= { pkcs-9(9) smime(16) ct(1) 2 }
which corresponds to the OID string "1.2.840.113549.1.9.16.1.2".
The Cryptographic Message Syntax (CMS, RFC 5652) specifies the AuthenticatedData content type for providing a syntax for recipient-specific protecting the integrity of a message by means of a Message Authentication Code (MAC). Content of any type may be authenticated for any number of recipients in parallel. For each recipient a randomly generated symmetric mac key is encrypted with the particular recipient key and - together with recipient-specific information - collected into a RecipientInfo value. A message authentication code on the content is computed with the mac key and -- together with the RecipientInfos objects -- packed into a AuthenticatedData message.
The AuthenticatedData content type is defined as:
```
 AuthenticatedData ::= SEQUENCE {
    version            Version,
    originatorInfo [0] IMPLICIT OriginatorInfo OPTIONAL,
    recipientInfos     RecipientInfos,
    macAlgorithm       MessageAuthenticationCodeAlgorithm,
    digestAlgorithm [1] DigestAlgorithmIdentifier OPTIONAL,
    encapContentInfo   EncapsulatedContentInfo,
    authAttrs [2]      IMPLICIT AuthAttributes OPTIONAL,
    mac                MessageAuthenticationCode,
    unauthAttrs [3]    IMPLICIT UnauthAttributes OPTIONAL }
 

 AuthAttributes ::= SET SIZE (1..MAX) OF Attribute
 UnauthAttributes ::= SET SIZE (1..MAX) OF Attribute
 MessageAuthenticationCode ::= OCTET STRING
 
```
If the digestAlgorithm field is not null, authenticated attributes have to be present and the MAC value is calculated on the DER encoding of the authenticated attributes. In this case the MessageDigest attribute has to be included as an authenticated attribute and has to contain a digest value computed on the content data. If no authenticated attributes are present, the MAC value is computed on the content itself.
A recipient, when receiving the AuthenticatedData message, decrypts the corresponding encrypted MAC key with his/her key and subsequently uses it to verify the message authentication code.

When creating an AuthenticatedData object an application has to decide whether the to-be-authenticated content shall be incldued (IMPLICIT mode) into the AuthenticatedData message or shall be transmitted by other means (EXPLICIT mode):
```
 int mode = AuthenticatedData.IMPLICIT; // include content
 
```
or
```
 int mode = AuthenticatedData.EXPLICIT; // do not include content
 
```
However, in both cases the content data has to be supplied when creating the AuthenticatedData object, because it is needed for the MAC computation:
```
 byte[] content = ...; // the content data to be authenticated
 
```
Together with transmission mode and content data the following values have to be specified when creating an AuthenticatedData object, some of them are only optional:
- content type: the type of the authenticated content (e.g. ObjectID.cms_data)
- content: a byte array supplying the to-be-authenticated data
- MAC algorithm: the OID of the MAC algorithm to be used
- MAC key length (optional): the length (in bytes) of the MAC key to be generated; if not specified (-1), a default value will be used depending on the MAC algorithm and the implementation of the SecurityProvider method generateKey.
- MAC parameters (optional): any parameters, if required by the MAC algorithm
- digest algorithm: the OID of the message digest algorithm to be used for hash computation if authenticated attributes are included
- transmission mode: either IMPLICIT (to include the content) or EXPLICIT to transmit it by other means
Optional originator information (if required by the key management technique in use} maybe set via method setOriginatorInfo, and authenticated or unauthenticated attributes maybe supplied by calling method setAuthenticatedAttributes or setUnauthenticatedAttributes, respectively, e.g.:
```
 // the content type
 ObjectID contentType = ObjectID.cms_data;
 // the content data to be authenticated
 byte[] content = ...;
 // the mac algorithm to be used
 AlgorithmID macAlgorithm = (AlgorithmID)AlgorithmID.hMAC_SHA1.clone();
 // the length of the mac key to be generated
 int macKeyLength = 64;
 // we do not need mac algorithm parameters
 AlgorithmParameterSpec macParams = null;
 // we want to include authenticated attributes and therefore need a digest algorithm
 AlgorithmID digestAlgorithm = (AlgorithmID)AlgorithmID.sha1.clone();
 // the transmission mode (either AuthenticatedData.IMPLICIT or AuthenticatedData.EXPLICIT)
 int mode = ...;
 // create the AuthenticatedData object:
 AuthenticatedData authenticatedData = new AuthenticatedData(contentType,
                                                             content, 
                                                             macAlgorithm,
                                                             macKeyLength,
                                                             macParams,
                                                             digestAlgorithm,
                                                             mode);
 
```
Just for demonstration we only add one authenticated attribute (ContentType):
```
 Attribute[] attributes = { new Attribute(new CMSContentType(contentType)) };
 authenticatedData.setAuthenticatedAttributes(attributes);
 
```
When authenticated attributes are present they at least must contain the ContentType and the (MessageDigest) attribute. It is not necessary for the application to provide the MessageDigest attribute since it is automatically calculated and set during the encoding procedure.
Recipient specific information is required to encrypt the secret MAC key and may be supplied by calling method setRecipientInfos. In our example we add two RecipientInfos (one for the the sender who wants to be able to verify the MAC, too, and one for the final recipient).
```
 // set the recipients of the authenticated message
 authenticatedData.setRecipientInfos(recipients);
 
```
Finally the AuthenticatedData object has to be prepared for transmission by transforming it into an ASN1Object or immediately DER encoding it. The former is done by calling method toASN1Object, the latter by using method getEncoded method:
```
 ASN1Object asn1AuthData = authenticatedData.toASN1Object();
 
```
or
```
 byte[] encoding = authenticatedData.getEncoded();
 
```
You alternatively may use a proper writeTo method of the parent AuthenticatedDataStream class for immediately encoding this AuthenticatedData object to an output stream. When using writeTo in implicit mode, you additionally have the possibility of specifying a particular blockSize for forcing an indefinite constructed encoding of the inherent content data bytes, instead of of the default definite primitive encoding, e.g:
```
 0x24 0x80
           0x04 0x02 0x01 0xAB
           0x04 0x02 0x23 0x7F
           0x04 0x01 0xCA
 0x00 0x00 
 
```
instead of:
```
 0x04 0x05 0x01 0xAB 0x23 0x7F 0xCA
 
```
for encoding the five data bytes 0x01 0xAB 0x23 0x7F 0xCA.

When receiving an AuthenticatedData message use the AuthenticatedData(InputStream) constructor for parsing the AuthenticatedData from its DER encoding:
```
 // the input stream supplying the DER encoded AuthenticatedData
 InputStream encodedStream = ...;
 // parse the AuthenticatedData
 AuthenticatedData authenticatedData = new AuthenticatedData(encodedStream);
 
```
If the content has been transmitted by other means (EXPLICIT mode) it now has to be supplied by calling method setContent since it is required for MAC computation (verification):
```
 if (authenticatedData.getMode() == AuthenticatedData.EXPLICIT) {
   // in explicit mode explicitly supply the content for hash/mac computation 
   byte[] content = ...; // the content received by other means
   authenticatedData.setContent(content);
 }
 
```
In order to decrypt the encrypted MAC key the recipient has to call a proper setupMac method thereby specifying her/his key encryption key which has to be suitable for the key management technique that has been used. Since in our example both recipients have used the key transport technique, a private key is required to decrypt the encrypted mac key. The right RecipientInfo maybe identified by the recipient certificate, e.g.:
```
 // the recipient certificate:
 X509Certificate recipientCert = ...; 
 // the corresponding private key
 PrivateKey recipientPrivateKey = ...;
 // setup the MAC by decrypting the secret MAC key
 autenticatedData.setupMac(recipientPrivateKey, recipientCert);
 
```
After decrypting the encrypted MAC key, the MAC value can be verified by calling method verifyMac:
```
 // verify the MAC  
 try {
   if (authenticatedData.verifyMac() == false) {
     System.out.println("Invalid MAC value!");
   }
 } catch (CMSMacException ex) {
   System.out.println("Mac verification error: " + ex.toString());
 }
 System.out.println("Mac successfully verified!");
 
```
Finally (in implicit mode) the content may be accessed by calling method getContent:
```
 byte[] content = authenticatedData.getContent();
 
```

Field Summary

Fields
Modifier and Type	Field and Description
`protected static int`	`AUTH_ATTRS_TAG`
`protected static int`	`DIGEST_ALGORITHM_TAG`
`static int`	`EXPLICIT` Denotes a mode where the content is included within the AuthenticatedData
`static int`	`IMPLICIT` Denotes a mode where the content is not transmitted within the AuthenticatedData
`protected Attributes`	`m_authAttrs` The authenticated attributes
`protected boolean`	`m_authKeyGenerated` A flag to indicate if the authenticated key has been generated
`protected int`	`m_blockSize` The block size for block oriented stream encoding.
`protected ObjectID`	`m_contentType` The content type.
`protected AlgorithmID`	`m_digestAlgorithm` The digest algorithm to use.
`protected java.security.DigestInputStream`	`m_digestInputStream` A class variable used to reference the DigetInputStream that wraps the InputStream.
`protected boolean`	`m_enableEncodeListener` Variable used to determine whether the encode listener should be used (for streaming support), or whether it should not be used (non-stream support)
`protected EncapsulatedContentInfoStream`	`m_encapContentInfo` The inherent EncapsualtedContentInfo.
`protected DerInputStream`	`m_enveloped_data` An `InputStream` holding the authenticated data.
`protected java.io.InputStream`	`m_inputStream` An InputStream holding the data
`protected boolean`	`m_inputStreamIsDigest` This boolean flag is used to indicate if the underlying input stream used is a DigestInputStream.
`protected byte[]`	`m_mac` The Mac value
`protected int`	`m_mac_length` The length of the Mac
`protected AlgorithmID`	`m_macAlgorithm` The MAC algorithm to use.
`protected java.security.spec.AlgorithmParameterSpec`	`m_macAlgParameters` The MAC AlgorithmParameterSpec
`protected MacInputStream`	`m_macInputStream` A class variable used to reference the MacInputStream that wraps the InputStream.
`protected int`	`m_mode` The mode specifying if the data shall be included (IMPLICIT), or if is not included (EXPLICIT).
`protected OriginatorInfo`	`m_originatorInfo` The originator Information encapsulated in an Object
`protected java.util.Vector<RecipientInfo>`	`m_recipientInfos` A list of RecipientInfo
`protected javax.crypto.SecretKey`	`m_secretKey` The Symmetric Mac Key (Message Authentication Key)
`protected SecurityProvider`	`m_securityProvider` The SecurityProvider to be used.
`protected Attributes`	`m_unauthAttrs` The unauthenticated attributes
`protected int`	`m_version` The CMS version number.
`protected static int`	`ORIGINATOR_INFO_TAG`
`protected static int`	`UNAUTH_ATTRS_TAG`

Constructor Summary

Constructors
Modifier	Constructor and Description
`protected`	`AuthenticatedDataStream()` Default constructor for dynamic object creation in ContentInfoStream.
	`AuthenticatedDataStream(java.io.InputStream is)` Creates an AuthenticatedDataStream from a BER encoded AutheticatedData object which is read from the given InputStream.
	`AuthenticatedDataStream(ObjectID contentType, java.io.InputStream data_is, AlgorithmID macAlgorithm, byte[] mac, AlgorithmID digestAlgorithm, int mode)` Creates an AuthenticatedDataStream from an already calculated MAC value.
	`AuthenticatedDataStream(ObjectID contentType, java.io.InputStream data_is, AlgorithmID macAlgorithm, int macKeyLength, java.security.spec.AlgorithmParameterSpec macAlgParameters, AlgorithmID digestAlgorithm, int mode)` Creates a new AuthenticatedDataStream where the to-be-authenticated content data is supplied by an input stream.
	`AuthenticatedDataStream(ObjectID contentType, java.io.InputStream data_is, AlgorithmID macAlgorithm, int macKeyLength, java.security.spec.AlgorithmParameterSpec macAlgParameters, int mode)` Creates a new AuthenticatedDataStream where the to-be-authenticated content data is supplied by an input stream.

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`void`	`addRecipientInfo(RecipientInfo recipientinfo)` Adds one recipient to the list of recipient infos Any `RecipientInfo` added supplies recipient-specific information used for identifying the key of the recipient to be used for en/decrypting the symmetric mac key
`void`	`decode(java.io.InputStream is)` Reads and decodes a BER encoded DigestedData from an input stream.
`void`	`encodeCalled(ASN1Object asn1, int id)` This method implements the EncodeListener interface.
`Attribute`	`getAuthenticatedAttribute(ObjectID objectid)`
`Attribute[]`	`getAuthenticatedAttributes()`
`byte[]`	`getAuthenticatedDigest()` Return the authenticated Digested which is alreay included in the authenticated Attributes.
`int`	`getBlockSize()` Gets the block size defining the length of each definite primitive encoded octet string component.
`ObjectID`	`getContentType()` Returns the content type this class implements.
`AlgorithmID`	`getDigestAlgorithm()` Returns the message-digest algorithm used for computing the digest.
`ObjectID`	`getEncapsulatedContentType()` Returns the content type the inherent EncapsulatetContentInfo represents.
`java.io.InputStream`	`getInputStream()` Returns an input stream with the raw data.
`byte[]`	`getMac()`
`javax.crypto.Mac`	`getMac(AlgorithmID algorithmid, java.security.Key key, java.security.spec.AlgorithmParameterSpec algorithmparameterspec)`
`AlgorithmID`	`getMacAlgorithm()` Returns the message-digest algorithm used for computing the digest.
`int`	`getMode()`
`OriginatorInfo`	`getOriginatorInfo()`
`RecipientInfo`	`getRecipientInfo(KeyIdentifier recipientIdentifier)`
`RecipientInfo`	`getRecipientInfo(X509Certificate recipientCertificate)`
`RecipientInfo[]`	`getRecipientInfos()`
`RecipientInfo[]`	`getRecipientInfos(int type)`
`Attribute`	`getUnauthenticatedAttribute(ObjectID objectid)`
`Attribute[]`	`getUnauthenticatedAttributes()`
`int`	`getVersion()`
`void`	`notifyEOF()` This method implements the EOFListener interface for performing the final decoding.
`void`	`setAuthenticatedAttributes(Attribute[] attributes)` Sets a set of (authenticated) attributes.
`void`	`setBlockSize(int blockSize)` Sets the block size for defining the length of each definite primitive encoded octet string component.
`void`	`setInputStream(java.io.InputStream is)` Sets the content suppliyng input stream.
`void`	`setOriginatorInfo(OriginatorInfo originatorInfo)` Sets the optional OriginatorInfo.
`void`	`setRecipientInfos(RecipientInfo[] recipients)` Sets the recipient infos: Any RecipientInfo added supplies recipient-specific information used for identifying the key of the recipient to be used for en/decrypting the symmetric mac key.
`void`	`setUnauthenticatedAttributes(Attribute[] attributes)` Sets a set of (unauthenticated) attributes.
`javax.crypto.SecretKey`	`setupMac(java.security.Key recipientKey, int recipientInfoIndex)` Uses the specified key for decrypting the MAC key and setting the MAC calculation for the requesting recipient, specified by its recipientInfoIndex.
`javax.crypto.SecretKey`	`setupMac(java.security.Key recipientKey, KeyIdentifier recipientIdentifier)` Uses the specified key for decrypting the MAC key and setup the MAC calculation for the requesting recipient, specified by the given recipient identifier.
`javax.crypto.SecretKey`	`setupMac(java.security.Key recipientKey, X509Certificate recipientCertificate)` Uses the specified key for decrypting the MAC key and setup the MAC calculation for the requesting recipient, specified by the given recipient identifier.
`void`	`setupMac(javax.crypto.SecretKey macKey)` Uses the given symmetric key to setup the MAC calculation to verify the message authentication code when parsing an AuthenticatedData object.
`ASN1Object`	`toASN1Object()` Returns this DigestedDataStream as ASN1Object.
`protected ASN1Object`	`toASN1Object(int blockSize)` Returns this DigestedData as ASN1Object where a constructed OCTET STRING is used for encoding the content.
`java.lang.String`	`toString()`
`java.lang.String`	`toString(boolean detailed)` Returns a string giving some information about this `DigestedData` object.
`boolean`	`verifyMac()` Verifies the message authentication code.
`void`	`writeTo(java.io.OutputStream os)` Writes this DigestedData DER encoded to the supplied output stream.
`void`	`writeTo(java.io.OutputStream os, int blockSize)` Writes this object to the supplied output stream where a constructed OCTET STRING is used for encoding the content.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

- Field Detail
  - UNAUTH_ATTRS_TAG
```
protected static final int UNAUTH_ATTRS_TAG
```
    See Also:
    
    Constant Field Values
  - AUTH_ATTRS_TAG
```
protected static final int AUTH_ATTRS_TAG
```
    See Also:
    
    Constant Field Values
  - DIGEST_ALGORITHM_TAG
```
protected static final int DIGEST_ALGORITHM_TAG
```
    See Also:
    
    Constant Field Values
  - ORIGINATOR_INFO_TAG
```
protected static final int ORIGINATOR_INFO_TAG
```
    See Also:
    
    Constant Field Values
  - IMPLICIT
```
public static final int IMPLICIT
```
    Denotes a mode where the content is not transmitted within the AuthenticatedData
    
    See Also:
    
    Constant Field Values
  - EXPLICIT
```
public static final int EXPLICIT
```
    Denotes a mode where the content is included within the AuthenticatedData
    
    See Also:
    
    Constant Field Values
  - m_enableEncodeListener
```
protected boolean m_enableEncodeListener
```
    Variable used to determine whether the encode listener should be used (for streaming support), or whether it should not be used (non-stream support)
  - m_version
```
protected int m_version
```
    The CMS version number. Default: 0.
  - m_macAlgorithm
```
protected AlgorithmID m_macAlgorithm
```
    The MAC algorithm to use.
  - m_mac
```
protected byte[] m_mac
```
    The Mac value
  - m_mac_length
```
protected int m_mac_length
```
    The length of the Mac
  - m_digestAlgorithm
```
protected AlgorithmID m_digestAlgorithm
```
    The digest algorithm to use.
  - m_contentType
```
protected ObjectID m_contentType
```
    The content type.
  - m_blockSize
```
protected int m_blockSize
```
    The block size for block oriented stream encoding.
  - m_secretKey
```
protected javax.crypto.SecretKey m_secretKey
```
    The Symmetric Mac Key (Message Authentication Key)
  - m_encapContentInfo
```
protected EncapsulatedContentInfoStream m_encapContentInfo
```
    The inherent EncapsualtedContentInfo.
  - m_inputStream
```
protected java.io.InputStream m_inputStream
```
    An InputStream holding the data
  - m_digestInputStream
```
protected java.security.DigestInputStream m_digestInputStream
```
    A class variable used to reference the DigetInputStream that wraps the InputStream. This is used for calculating the digest value when the data is read as a stream.
  - m_macInputStream
```
protected MacInputStream m_macInputStream
```
    A class variable used to reference the MacInputStream that wraps the InputStream. This is used for calculating the MAC when the data is calculated over the content data.
  - m_inputStreamIsDigest
```
protected boolean m_inputStreamIsDigest
```
    This boolean flag is used to indicate if the underlying input stream used is a DigestInputStream.
    If set to true, then the Digest is calculated as part of the Authenticated Attributes:
```
 If authAttrs field is present, the content-type attribute (as
 described in Section 11.1) and the message-digest attribute (as
 described in section 11.2) MUST be included, and the input to the MAC
 calculation process is the DER encoding of authAttrs. 
 
```
    If set to false, then the MAC is calculated over the OCTET_String contents:
```
 If authAttrs field is absent, the input to the MAC calculation
 process is the value of the encapContentInfo eContent OCTET STRING.
 
```
  - m_mode
```
protected int m_mode
```
    The mode specifying if the data shall be included (IMPLICIT), or if is not included (EXPLICIT).
  - m_originatorInfo
```
protected OriginatorInfo m_originatorInfo
```
    The originator Information encapsulated in an Object
  - m_recipientInfos
```
protected java.util.Vector<RecipientInfo> m_recipientInfos
```
    A list of RecipientInfo
  - m_authKeyGenerated
```
protected boolean m_authKeyGenerated
```
    A flag to indicate if the authenticated key has been generated
  - m_authAttrs
```
protected Attributes m_authAttrs
```
    The authenticated attributes
  - m_unauthAttrs
```
protected Attributes m_unauthAttrs
```
    The unauthenticated attributes
  - m_enveloped_data
```
protected DerInputStream m_enveloped_data
```
    An InputStream holding the authenticated data.
  - m_securityProvider
```
protected SecurityProvider m_securityProvider
```
    The SecurityProvider to be used.
  - m_macAlgParameters
```
protected java.security.spec.AlgorithmParameterSpec m_macAlgParameters
```
    The MAC AlgorithmParameterSpec
- Constructor Detail
  - AuthenticatedDataStream
```
protected AuthenticatedDataStream()
```
    Default constructor for dynamic object creation in ContentInfoStream. Shall be not used by an application.
  - AuthenticatedDataStream
```
public AuthenticatedDataStream(java.io.InputStream is)
                        throws java.io.IOException,
                               CMSParsingException
```
    Creates an AuthenticatedDataStream from a BER encoded AutheticatedData object which is read from the given InputStream. The encoded AutheticatedData may (or may not) be wrapped into a ContentInfo.
    
    Parameters:
    
    is - the InputStream holding the BER encoded CMS AuthenticatedData object
    
    Throws:
    
    java.io.IOException - if an error occurs when reasding from the stream
    
    CMSParsingException - if the object can not be parsed
  - AuthenticatedDataStream
```
public AuthenticatedDataStream(ObjectID contentType,
                               java.io.InputStream data_is,
                               AlgorithmID macAlgorithm,
                               byte[] mac,
                               AlgorithmID digestAlgorithm,
                               int mode)
                        throws CMSException
```
    Creates an AuthenticatedDataStream from an already calculated MAC value. No MAC or digest calculation is initialized. If setAuthenticatedAttributes are supplied, they already have to contain the MessageDigest attribute. Any RecipientInfo added to this AuthenticatedDataStream already has to contain the encrypted MAC key (i.e. no MAC key is generated and encrypted for each recipient).
    
    Parameters:
    
    contentType - the content type of the data to be digested
    
    data_is - the data to be digested supplied from an input stream
    
    macAlgorithm - - the OID of the MAC algorithm used for MAC calculation
    
    mac - - the already calculated MAC value
    
    digestAlgorithm - - the OID of the digest algorithm used for hash calculation
    
    mode - - the transmission mode; either IMPLICIT (to include the content) or EXPLICIT to transmit it by other means
    
    Throws:
    
    CMSException - if the supplied parameters to not satisfy the requirements or there is no implementation for the requested hash algorithm
  - AuthenticatedDataStream
```
public AuthenticatedDataStream(ObjectID contentType,
                               java.io.InputStream data_is,
                               AlgorithmID macAlgorithm,
                               int macKeyLength,
                               java.security.spec.AlgorithmParameterSpec macAlgParameters,
                               AlgorithmID digestAlgorithm,
                               int mode)
                        throws CMSException
```
    Creates a new AuthenticatedDataStream where the to-be-authenticated content data is supplied by an input stream. This constructor generates a symmetric MAC key. If the digestAlg parameter is not null, a stream is used to wrap a hash calculating input stream around the data supplying input stream. In this case authenticated attributes have to be set by calling method setAuthenticatedAttributes and the MAC value is calculated from the DER encoded authenticated attributes which have to contain the -- (if not set) automatically calculated -- MessageDigest attribute. However, if the digestAlg parameter is null, a MAC Stream is used to wrap a MAC calculating input stream around the data supplying input stream for calculating the MAC value immediately from the content.
    
    Parameters:
    
    contentType - the content type of the data to be digested
    
    data_is - the data to be digested supplied from an input stream
    
    macAlgorithm - - the OID of the MAC algorithm to be used
    
    macKeyLength - - the length (in bytes) of the MAC key to be generated; if not specified (-1), a default value will be used depending on the MAC algorithm and the implementation of the SecurityProvider method generateKey. The toolkit tries to determine the block length of the MAC algorithm in use; otherwise it uses the length of the underlying digest algorithm.
    
    macAlgParameters - - any parameters, if required by the MAC algorithm
    
    digestAlgorithm - - the OID of the digest algorithm to be used for hash computation if authenticated attributes are to be included
    
    mode - - the transmission mode; either IMPLICIT (to include the content) or EXPLICIT to transmit it by other means
    
    Throws:
    
    CMSException - if the supplied parameters to not satisfy the requirements or there is no implementation for the requested hash algorithm
  - AuthenticatedDataStream
```
public AuthenticatedDataStream(ObjectID contentType,
                               java.io.InputStream data_is,
                               AlgorithmID macAlgorithm,
                               int macKeyLength,
                               java.security.spec.AlgorithmParameterSpec macAlgParameters,
                               int mode)
                        throws CMSException
```
    Creates a new AuthenticatedDataStream where the to-be-authenticated content data is supplied by an input stream. This constructor generates a symmetric MAC key and uses an InputStreamMacEngine to wrap a MAC calculating input stream around the data supplying input stream.
    
    Parameters:
    
    contentType - the type of the authenticated content (e.g. ObjectID.cms_data)
    
    data_is - an input stream supplying the to-be-authenticated data
    
    macAlgorithm - - the OID of the MAC algorithm to be used
    
    macKeyLength - - the length (in bytes) of the MAC key to be generated; if not specified (-1), a default value will be used depending on the MAC algorithm and the implementation of the SecurityProvider method generateKey. The toolkit tries to determine the block length of the MAC algorithm in use; otherwise it uses the length of the underlying digest algorithm.
    
    macAlgParameters - - any parameters, if required by the MAC algorithm
    
    mode - - the transmission mode; either IMPLICIT (to include the content) or EXPLICIT to transmit it by other means
    
    Throws:
    
    CMSException - if the supplied parameters to not satisfy the requirements or there is no implementation for the requested hash algorithm
- Method Detail
  - addRecipientInfo
```
public void addRecipientInfo(RecipientInfo recipientinfo)
```
    Adds one recipient to the list of recipient infos Any RecipientInfo added supplies recipient-specific information used for identifying the key of the recipient to be used for en/decrypting the symmetric mac key
    
    Parameters:
    
    recipientinfo - the RecipientInfo to be added
  - decode
```
public void decode(java.io.InputStream is)
            throws java.io.IOException,
                   CMSParsingException
```
    Reads and decodes a BER encoded DigestedData from an input stream. AuthenticatedData ::= SEQUENCE { version Version, originatorInfo [0] IMPLICIT OriginatorInfo OPTIONAL, recipientInfos RecipientInfos, macAlgorithm MessageAuthenticationCodeAlgorithm, digestAlgorithm [1] DigestAlgorithmIdentifier OPTIONAL, encapContentInfo EncapsulatedContentInfo, authAttrs [2] IMPLICIT AuthAttributes OPTIONAL, mac MessageAuthenticationCode, unauthAttrs [3] IMPLICIT UnauthAttributes OPTIONAL }
    
    Specified by:
    
    decode in interface ContentStream
    
    Parameters:
    
    is - the InputStream holding a BER encoded CMS DigestedData object
    
    Throws:
    
    java.io.IOException - if an I/O error occurs during reading from the InputStream
    
    CMSParsingException - if an error occurs while parsing the object
  - encodeCalled
```
public void encodeCalled(ASN1Object asn1,
                         int id)
                  throws CodingException
```
    This method implements the EncodeListener interface. During the encoding process the DerCoder calls this method when it actually is time for computing and setting the message digest to be encoded. In particular for the stream-supporting implementation of this DigestedData content type, the message digest cannot be computed before the content stream entirely has been read. Since the content stream actually is read during the encoding procedure, this class has to be notified when the content stream has been read. This is done by means of the EncodeListener utility. The toASN1Object() method of this AuthenticatedDataStream class instantiates an empty OCTET_STRING for the digest field, and registers itself as EncodeListener for this empty OCTET_STRING. Now, during the encoding process, when the content stream entirely has been read, this encodeCalled method is called for performing digest computation. The supplied ASN1Object is the empty OCTET_STRING to be "filled" with the result of the digest-computation.
    
    Specified by:
    
    encodeCalled in interface EncodeListener
    
    Parameters:
    
    asn1 - The ASN1Object which will append the digest and MAC values during the encoding of the stream.
    
    id - the id identifying the particular component to be processed, not used by this implementation.
    
    Throws:
    
    CodingException - if an error occurs when computing/encrypting the message digest
  - getMac
```
public javax.crypto.Mac getMac(AlgorithmID algorithmid,
                               java.security.Key key,
                               java.security.spec.AlgorithmParameterSpec algorithmparameterspec)
                        throws java.security.InvalidAlgorithmParameterException,
                               java.security.NoSuchAlgorithmException,
                               java.security.InvalidKeyException,
                               java.security.NoSuchProviderException
```
    Parameters:
    
    algorithmid - The algorithmID for the Mac algorithm
    
    key - The Key used to initilaize the MAC algorithm
    
    algorithmparameterspec - The algorihtm parameters if required.
    
    Returns:
    
    The javax.crypto.Mac algorithm given the algorithmID, Mac Key and algorithmParameterSpec. This method uses the Entrust provider to return the specified Mac algorithm.
    
    Throws:
    
    java.security.InvalidAlgorithmParameterException
    
    java.security.NoSuchAlgorithmException
    
    java.security.InvalidKeyException
    
    java.security.NoSuchProviderException
  - getAuthenticatedAttribute
```
public Attribute getAuthenticatedAttribute(ObjectID objectid)
```
    Parameters:
    
    objectid -
    
    Returns:
    
    the first authenticated attribute matching to the given ObjectID, if included in this AutheticatedData object.
  - getAuthenticatedAttributes
```
public Attribute[] getAuthenticatedAttributes()
```
    Returns:
    
    the Authenticated attributes
  - getBlockSize
```
public int getBlockSize()
```
    Gets the block size defining the length of each definite primitive encoded octet string component. If the value of blockSize is smaller or equal to zero the whole data is encoded as definite primitive octet string.
    
    Specified by:
    
    getBlockSize in interface ContentStream
    
    Returns:
    
    blockSize defining the encoding scheme and setting the octet string component length, if positive
  - getContentType
```
public ObjectID getContentType()
```
    Returns the content type this class implements.
    
    Specified by:
    
    getContentType in interface ContentStream
    
    Returns:
    
    ObjectID.cms_authData
  - getDigestAlgorithm
```
public AlgorithmID getDigestAlgorithm()
```
    Returns the message-digest algorithm used for computing the digest.
    
    Returns:
    
    the ID of the message-digest algorithm
  - getEncapsulatedContentType
```
public ObjectID getEncapsulatedContentType()
```
    Returns the content type the inherent EncapsulatetContentInfo represents.
    
    Returns:
    
    the content type the inherent EncapsulatetContentInfo represents
  - getInputStream
```
public java.io.InputStream getInputStream()
```
    Returns an input stream with the raw data.
    
    Returns:
    
    an input stream with the raw data
  - getMac
```
public byte[] getMac()
```
    Returns:
    
    the MAC value
  - getMacAlgorithm
```
public AlgorithmID getMacAlgorithm()
```
    Returns the message-digest algorithm used for computing the digest.
    
    Returns:
    
    the ID of the message-digest algorithm
  - getMode
```
public int getMode()
```
    Returns:
    
    the mode used, either IMPLICIT(1) or EXPLICIT(2)
  - getOriginatorInfo
```
public OriginatorInfo getOriginatorInfo()
```
    Returns:
    
    the originatorInfo if it has been included
  - getRecipientInfo
```
public RecipientInfo getRecipientInfo(KeyIdentifier recipientIdentifier)
```
    Parameters:
    
    recipientIdentifier -
    
    Returns:
    
    the RecipientInfo belonging to the recipient identified by the given recipient identifier.
  - getRecipientInfo
```
public RecipientInfo getRecipientInfo(X509Certificate recipientCertificate)
```
    Parameters:
    
    recipientCertificate - the recipient Certificate
    
    Returns:
    
    the recipient info matching to the supplied recipient certificate.
  - getRecipientInfos
```
public RecipientInfo[] getRecipientInfos()
```
    Returns:
    
    all the recipient infos included in this AutheticatedData object.
  - getRecipientInfos
```
public RecipientInfo[] getRecipientInfos(int type)
```
    Parameters:
    
    type - the RecipientInfo type
    
    Returns:
    
    all the recipient infos included in this AutheticatedData object that have the specified type.
    
    See Also:
    
    RecipientInfo
  - getUnauthenticatedAttribute
```
public Attribute getUnauthenticatedAttribute(ObjectID objectid)
```
    Parameters:
    
    objectid - the objectID of the unauthenticated attribute
    
    Returns:
    
    the first unauthenticated attribute matching to the given ObjectID, if included in this AutheticatedData object.
  - getUnauthenticatedAttributes
```
public Attribute[] getUnauthenticatedAttributes()
```
    Returns:
    
    the unauthenticated attributes included in this AutheticatedData.
  - getVersion
```
public int getVersion()
```
    Returns:
    
    the version syntax number
  - notifyEOF
```
public void notifyEOF()
               throws java.io.IOException
```
    This method implements the EOFListener interface for performing the final decoding. Since the digest field is located at the end of a DigestedData structure, it only can be accessed after reading the data stream. For that reason, when starting the parsing of an implicit AuthenticatedData message only version, origintatorInfo, recipientInfos, macAlgoirthm, and encapContentInfo fields can be parsed before reading the data. Since the data is supplied from an input stream, a NotifyEOFInputStream is wrapped around this raw data stream for indicating that the parsing procedure is to be notified when the stream actually has been read. At that point, the program exceuting automatically jumps to the actual notifyEOF method for finishing the decoding by parsing the final unauthenticated attributes field.
    For any application it is strongly recommended not to explicitly call this method.
    
    Specified by:
    
    notifyEOF in interface EOFListener
    
    Throws:
    
    java.io.IOException
  - setAuthenticatedAttributes
```
public void setAuthenticatedAttributes(Attribute[] attributes)
```
    Sets a set of (authenticated) attributes. If authenticated attributes are present, the MAC value is calculated from the DER encoded authenticated attributes which have to contain the MessageDigest attribute. In this case the digestAlgorithm field is not allowed to be null since it identifies the algorithm to be used for calculating a digest value from the content and set it as MessageDigest attribute. If the MessageDigest attribute is not included in the set of attributes supplied to this methode, it is automatically calculated and set.
  - setBlockSize
```
public void setBlockSize(int blockSize)
```
    Sets the block size for defining the length of each definite primitive encoded octet string component. If the value of blockSize is smaller or equal to zero the whole data is encoded as definite primitive octet string. This method may be used for enforcing block encoding when wrapping the DigestedData into a ContentInfo.
    
    Specified by:
    
    setBlockSize in interface ContentStream
    
    Parameters:
    
    blockSize - for defining the encoding scheme and setting the octet string component length, if positive
  - setInputStream
```
public void setInputStream(java.io.InputStream is)
```
    Sets the content suppliyng input stream. When having created a new AuthenticatedDataStream object to be encoded to a stream, this method may be used to supply the content to be authenticated. When having decoded and parsed a received AuthenticatedDataStream object coming from some stream, this method may be used for supplying the content transmitted by other means (EXPLICIT mode).
    
    Parameters:
    
    is - the input stream holding the content data to be authenticated
  - setOriginatorInfo
```
public void setOriginatorInfo(OriginatorInfo originatorInfo)
```
    Sets the optional OriginatorInfo. The originatorInfo may be set for including certificates and/or certificate revocation lists for the originator if required by the key management algorithm used.
    
    Parameters:
    
    originatorInfo - The OriginatorInfo object representing information about message origination
  - setRecipientInfos
```
public void setRecipientInfos(RecipientInfo[] recipients)
```
    Sets the recipient infos: Any RecipientInfo added supplies recipient-specific information used for identifying the key of the recipient to be used for en/decrypting the symmetric mac key. Parameters:
    
    Parameters:
    
    recipients - - a collection of per-recipient information
  - setUnauthenticatedAttributes
```
public void setUnauthenticatedAttributes(Attribute[] attributes)
```
    Sets a set of (unauthenticated) attributes.
    
    Parameters:
    
    attributes - the unauthenticated attributes to be set
  - setupMac
```
public javax.crypto.SecretKey setupMac(java.security.Key recipientKey,
                                       int recipientInfoIndex)
                                throws java.security.InvalidKeyException,
                                       java.security.NoSuchAlgorithmException,
                                       CMSException
```
    Uses the specified key for decrypting the MAC key and setting the MAC calculation for the requesting recipient, specified by its recipientInfoIndex.
    This method first uses the given key for decrypting the encrypted temporary symmetric key obtained from the corresponding RecipientInfo structure, and subsequently uses this MAC key to initialize the MAC calculation. The MAC calculation actually is done during reading the data obtained by calling method getInputStream. So do not call method getInputStream before setting up the MAC engine or behind verifying the MAC, e.g.:
```
 // the input stream supplying the BER encoded AuthenticatedData
 InputStream encodedStream = ...;
 // parse the AuthenticatedData
 AuthenticatedDataStream authenticatedData = new AuthenticatedDataStream(encodedStream);
 if (authenticatedData.getMode() == AuthenticatedDataStream.EXPLICIT) {
 // in explicit mode explicitly supply the content for hash/mac computation 
    InputStream contentIs = ...; // the content supplied from an input stream
    authenticatedData.setInputStream(contentIs);
  }
  // the index into the recipientInfos field
  int recipientIndex = ...; 
  // the corresponding recipient key
  Key recipientKey = ...;
  // decrypt the encrypted MAC key with the private key of the recipient:
  autenticatedData.setupMac(recipientKey, recipientIndex);
  InputStream contentIs = authenticatedData.getInputStream();
  byte[] buf = new byte[1024];
  int r;
  while ((r = data_is.read(buf)) > 0) {
     // do something useful
  } 
  // verify the MAC  
  try {
     if (authenticatedData.verifyMac() == false) {
        System.out.println("Invalid MAC value!");
     }
  } 
  catch (CMSMacException ex) {
     System.out.println("Mac verification error: " + ex.toString());
  }
  System.out.println("Mac successfully verified!");
  
```
    Note that you have to know the right index into the recipientInfos field when using this method for setting up the MAC calculation. You may search for the index by using one of the getRecipientInfo methods thereby identifying the recipient by its keyIdentifier or -- if suitable for the key management algorithm used -- certificate.
    However, when having some recipient using a key agreement protocol the corresponding RecipientInfo is of type KeyAgreeRecipientInfo which may hold encrypted MAC keys for more than only one recipients using the same key agreement algorithm with same domain parameters. Since this setupMac method only can get the KeyAgreeRecipientInfo with the given index (but not search for the right recipient in the KeyAgreeRecipientInfo), it will step through any recipient included in the KeyAgreeRecipientInfo trying to decrypt the encrypted MAC key with the supplied key. This may give some overhead; so it might be appropriate to use another setupMac method allowing to immediately identify the particular recipient in mind by its #setupMac(Key, KeyIdentifier) keyIdentifier} or certificate.
    Parameters:
    
    recipientKey - - the key of the recipient to be used for decrypting the encrypted mac key.
    
    recipientInfoIndex - - the index into the recipientInfos field
    
    Returns:
    
    the (decrypted) secret mac key
    
    Throws:
    
    CMSException - - if there occurs an error while decrypting the mac key or setting up the mac calculation, or no RecipientInfo for the requested recipient is included
    
    java.security.NoSuchAlgorithmException - - if there is no implementation of the mac algorithm
    
    java.security.InvalidKeyException - - if the specified key is not valid
  - setupMac
```
public javax.crypto.SecretKey setupMac(java.security.Key recipientKey,
                                       KeyIdentifier recipientIdentifier)
                                throws java.security.InvalidKeyException,
                                       java.security.NoSuchAlgorithmException,
                                       CMSException
```
    Uses the specified key for decrypting the MAC key and setup the MAC calculation for the requesting recipient, specified by the given recipient identifier. This method first uses the given key for decrypting the encrypted temporary symmetric key obtained from the corresponding RecipientInfo structure, and subsequently uses this mac key to initialize the mac calculation. The MAC calculation actually is done during reading the data obtained by calling method getInputStream. So do not call method getInputStream before setting up the MAC engine or behind verifying the mac, e.g.:
```
  // the input stream supplying the BER encoded AuthenticatedData
  InputStream encodedStream = ...;
  // parse the AuthenticatedData
  AuthenticatedDataStream authenticatedData = new AuthenticatedDataStream(encodedStream);
  if (authenticatedData.getMode() == AuthenticatedDataStream.EXPLICIT) {
     // in explicit mode explicitly supply the content for hash/mac computation 
     InputStream contentIs = ...; // the content supplied from an input stream
     authenticatedData.setInputStream(contentIs);
  }
  // the KeyIdentifier identifying the recipient key
  KeyIdentifier recipientIdentifier = ...; 
  // the corresponding recipient key
  Key recipientKey = ...;
  // decrypt the encrypted MAC key with the private key of the recipient:
  autenticatedData.setupMac(recipientKey, recipientIdentifier);
  InputStream contentIs = authenticatedData.getInputStream();
  byte[] buf = new byte[1024];
  int r;
  while ((r = data_is.read(buf)) > 0) {
     // do something useful
  } 
  // verify the MAC  
  try {
    if (authenticatedData.verifyMac() == false) {
        System.out.println("Invalid MAC value!");
    }
  } 
  catch (CMSMacException ex) {
     System.out.println("Mac verification error: " + ex.toString());
  }
  System.out.println("Mac successfully verified!");
 
```
    This setupMac method can be used to setup the MAC engine any type of RecipientInfo. The supplied recipient identifier will be used for searching for the right RecipientInfo in the recipientInfos field.
    Parameters:
    
    recipientKey - - the key of the recipient to be used for decrypting the encrypted mac key.
    
    recipientIdentifier - - specifies which RecipientInfo the given key belongs to
    
    Returns:
    
    the SecretKey
    
    Throws:
    
    java.security.InvalidKeyException
    
    java.security.NoSuchAlgorithmException
    
    CMSException
  - setupMac
```
public javax.crypto.SecretKey setupMac(java.security.Key recipientKey,
                                       X509Certificate recipientCertificate)
                                throws java.security.InvalidKeyException,
                                       java.security.NoSuchAlgorithmException,
                                       CMSException
```
    Uses the specified key for decrypting the MAC key and setup the MAC calculation for the requesting recipient, specified by the given recipient identifier.
    This method first uses the given key for decrypting the encrypted temporary symmetric key obtained from the corresponding RecipientInfo structure, and subsequently uses this MAC key to initialize the mac calculation. The MAC calculation actually is done during reading the data obtained by calling method getInputStream. So do not call method getInputStream() before setting up the mac engine or behind verifying the mac, e.g.:
```
  // the input stream supplying the BER encoded AuthenticatedData
  InputStream encodedStream = ...;
  // parse the AuthenticatedData
  AuthenticatedDataStream authenticatedData = new AuthenticatedDataStream(encodedStream);
  if (authenticatedData.getMode() == AuthenticatedDataStream.EXPLICIT) {
     // in explicit mode explicitly supply the content for hash/mac computation 
     InputStream contentIs = ...; // the content supplied from an input stream
     authenticatedData.setInputStream(contentIs);
  }
  // the recipient certificate:
  X509Certificate recipientCert = ...; 
  // the corresponding private key
  PrivateKey recipientPrivateKey = ...;
  // setup the MAC by decrypting the secret MAC key
  autenticatedData.setupMac(recipientPrivateKey, recipientCert);
  InputStream contentIs = authenticatedData.getInputStream();
  byte[] buf = new byte[1024];
  int r;
  while ((r = data_is.read(buf)) > 0) {
     // do something useful
  } 
  // verify the MAC  
  try {
    if (authenticatedData.verifyMac() == false) {
        System.out.println("Invalid MAC value!");
    }
  } 
  catch (CMSMacException ex) {
     System.out.println("Mac verification error: " + ex.toString());
  }
  System.out.println("Mac successfully verified!");
 
```
    This setupMac method can be used to setup the MAC engine any type of RecipientInfo. The supplied recipient identifier will be used for searching for the right RecipientInfo in the recipientInfos field.
    Parameters:
    
    recipientKey - - the key of the recipient to be used for decrypting the encrypted mac key.
    
    recipientCertificate - - specifies which RecipientInfo the given key belongs to
    
    Returns:
    
    the SecretKey
    
    Throws:
    
    java.security.InvalidKeyException
    
    java.security.NoSuchAlgorithmException
    
    CMSException
  - setupMac
```
public void setupMac(javax.crypto.SecretKey macKey)
              throws java.security.InvalidKeyException,
                     java.security.NoSuchAlgorithmException,
                     CMSException
```
    Uses the given symmetric key to setup the MAC calculation to verify the message authentication code when parsing an AuthenticatedData object.
    The secret key supplied to this method has to be the already decrypted MAC key.
    The MAC calculation actually is done during reading the data obtained by calling method getInputStream. So do not call method getInputStream before setting up the mac engine or behind verifying the mac, e.g.:
```
 // the input stream supplying the BER encoded AuthenticatedData
 InputStream encodedStream = ...;
 // parse the AuthenticatedData
 AuthenticatedDataStream authenticatedData = new AuthenticatedDataStream(encodedStream);
 if (authenticatedData.getMode() == AuthenticatedDataStream.EXPLICIT) {
    // in explicit mode explicitly supply the content for hash/mac computation 
   InputStream contentIs = ...; // the content supplied from an input stream
   authenticatedData.setInputStream(contentIs);
 }
 //the MAC key
 Key macKey = ...;
 // setup the MAC engine
 autenticatedData.setupMac(macKey);
 InputStream contentIs = authenticatedData.getInputStream();
 byte[] buf = new byte[1024];
 int r;
 while ((r = data_is.read(buf)) > 0) {
    // do something useful
 } 
 // verify the MAC  
 try {
    if (authenticatedData.verifyMac() == false) {
    System.out.println("Invalid MAC value!");
 } catch (CMSMacException ex) {
    System.out.println("Mac verification error: " + ex.toString());
 }
 System.out.println("Mac successfully verified!");
```
    Parameters:
    
    macKey - the temporary symmetric key that has been used to calculate the message authentication code
    
    Throws:
    
    java.security.InvalidKeyException
    
    java.security.NoSuchAlgorithmException
    
    CMSException
  - toASN1Object
```
public ASN1Object toASN1Object()
                        throws CMSException
```
    Returns this DigestedDataStream as ASN1Object.
    
    Specified by:
    
    toASN1Object in interface ContentStream
    
    Returns:
    
    this DigestedDataStream as ASN1Object
    
    Throws:
    
    CMSException - if the ASN1Object could not be created
  - toASN1Object
```
protected ASN1Object toASN1Object(int blockSize)
                           throws CMSException
```
    Returns this DigestedData as ASN1Object where a constructed OCTET STRING is used for encoding the content.
    
    Parameters:
    
    blockSize - the block size defining the encoding scheme - and specifying the length of each primitive encoded octet string component, if positive
    
    Throws:
    
    CMSException - if the ASN1Object could not be created
  - toString
```
public java.lang.String toString()
```
    Overrides:
    
    toString in class java.lang.Object
    
    Returns:
    
    a String representation of the Authenticated data
  - toString
```
public java.lang.String toString(boolean detailed)
```
    Returns a string giving some information about this DigestedData object.
    
    Specified by:
    
    toString in interface ContentStream
    
    Parameters:
    
    detailed - whether or not to give detailed information about the implemented CMS content type.
    
    Returns:
    
    the string representation
  - verifyMac
```
public boolean verifyMac()
                  throws CMSException
```
    Verifies the message authentication code. For verifying the MAC value first the MAC calculation has to be set up by calling a proper setupMac method and the content data has to be entirely read:
```
 // the input stream supplying the BER encoded AuthenticatedData
 InputStream encodedStream = ...;
 // parse the AuthenticatedData
 AuthenticatedDataStream authenticatedData = new AuthenticatedDataStream(encodedStream);
 if (authenticatedData.getMode() == AuthenticatedDataStream.EXPLICIT) {
     // in explicit mode explicitly supply the content for hash/mac computation 
     InputStream contentIs = ...; // the content supplied from an input stream
     authenticatedData.setInputStream(contentIs);
 }
 // the recipient certificate:
 X509Certificate recipientCert = ...; 
 // the corresponding private key
 PrivateKey recipientPrivateKey = ...;
 // setup the MAC by decrypting the secret MAC key
 autenticatedData.setupMac(recipientPrivateKey, recipientCert);
 InputStream contentIs = authenticatedData.getInputStream();
 byte[] buf = new byte[1024];
 int r;
 while ((r = data_is.read(buf)) > 0) {
    // do something useful
 } 
 // verify the MAC  
 try {
    if (authenticatedData.verifyMac() == false) {
        System.out.println("Invalid MAC value!");
    }
 } catch (CMSMacException ex) {
 System.out.println("Mac verification error: " + ex.toString());
 }
 System.out.println("Mac successfully verified!");
```
    Returns:
    
    true if the MAC verifies, false if not
    
    Throws:
    
    CMSMacException - - if the MAC verification process fails for some reason (e.g. the authenticated attributes (if incldued) cannot be parsed or the content hash does not match to value of the included MessageDigest attribute)
    
    CMSException
  - getAuthenticatedDigest
```
public byte[] getAuthenticatedDigest()
                              throws CMSException
```
    Return the authenticated Digested which is alreay included in the authenticated Attributes.
    
    Returns:
    
    the digest as a byte[]
    
    Throws:
    
    CMSException
  - writeTo
```
public void writeTo(java.io.OutputStream os)
             throws java.io.IOException
```
    Writes this DigestedData DER encoded to the supplied output stream. If for the inherent content structure a positive blocksize has been specified, the content is encoded as indefinite constructed octet string.
    
    Parameters:
    
    os - the output stream to which this DigestedData shall be written
    
    Throws:
    
    java.io.IOException - if an IOException occurs while writing to the stream
  - writeTo
```
public void writeTo(java.io.OutputStream os,
                    int blockSize)
             throws java.io.IOException
```
    Writes this object to the supplied output stream where a constructed OCTET STRING is used for encoding the content. If block size has a value > 0, in implicit mode the inherent raw data is encoded as constructed OCTET STRING. In this case the encoding is splitted according to the defined block size:
```
 0x24 0x80
           0x04 <blocksize> <data>
           0x04 <blocksize> <data>
           0x04 <blocksize> <data>
                ...
 0x00 0x00
 
```
    If the block size is not positive, whole the inherent data is encoded as one single primitive definite octet string:
```
 0x04 <length> <data>
 
```
    Parameters:
    
    os - the output stream to which this DigestedData shall be written
    
    blockSize - the block size defining the encoding scheme - and specifying the length of each primitive encoded octet string component, if positive
    
    Throws:
    
    java.io.IOException - if an error occurs during writing the object

Class AuthenticatedDataStream

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

UNAUTH_ATTRS_TAG

AUTH_ATTRS_TAG

DIGEST_ALGORITHM_TAG

ORIGINATOR_INFO_TAG

IMPLICIT

EXPLICIT

m_enableEncodeListener

m_version

m_macAlgorithm

m_mac

m_mac_length

m_digestAlgorithm

m_contentType

m_blockSize

m_secretKey

m_encapContentInfo

m_inputStream

m_digestInputStream

m_macInputStream

m_inputStreamIsDigest

m_mode

m_originatorInfo

m_recipientInfos

m_authKeyGenerated

m_authAttrs

m_unauthAttrs

m_enveloped_data

m_securityProvider

m_macAlgParameters

Constructor Detail

AuthenticatedDataStream

AuthenticatedDataStream

AuthenticatedDataStream

AuthenticatedDataStream

AuthenticatedDataStream

Method Detail

addRecipientInfo

decode

encodeCalled

getMac

getAuthenticatedAttribute

getAuthenticatedAttributes

getBlockSize

getContentType

getDigestAlgorithm

getEncapsulatedContentType

getInputStream

getMac

getMacAlgorithm

getMode

getOriginatorInfo

getRecipientInfo

getRecipientInfo

getRecipientInfos

getRecipientInfos

getUnauthenticatedAttribute

getUnauthenticatedAttributes

getVersion

notifyEOF

setAuthenticatedAttributes

setBlockSize

setInputStream

setOriginatorInfo

setRecipientInfos

setUnauthenticatedAttributes

setupMac

setupMac

setupMac

setupMac

toASN1Object

toASN1Object

toString

toString

verifyMac