package org.spongycastle.cms; import java.io.ByteArrayInputStream; import java.io.IOException; import java.io.InputStream; import java.security.AlgorithmParameters; import java.security.NoSuchProviderException; import java.security.Provider; import org.spongycastle.asn1.ASN1Encodable; import org.spongycastle.asn1.ASN1EncodableVector; import org.spongycastle.asn1.ASN1OctetString; import org.spongycastle.asn1.ASN1OctetStringParser; import org.spongycastle.asn1.ASN1SequenceParser; import org.spongycastle.asn1.ASN1Set; import org.spongycastle.asn1.ASN1SetParser; import org.spongycastle.asn1.BERTags; import org.spongycastle.asn1.DERSet; import org.spongycastle.asn1.cms.AttributeTable; import org.spongycastle.asn1.cms.AuthenticatedDataParser; import org.spongycastle.asn1.cms.CMSAttributes; import org.spongycastle.asn1.cms.ContentInfoParser; import org.spongycastle.asn1.cms.OriginatorInfo; import org.spongycastle.asn1.x509.AlgorithmIdentifier; import org.spongycastle.cms.jcajce.JceAlgorithmIdentifierConverter; import org.spongycastle.operator.DigestCalculatorProvider; import org.spongycastle.operator.OperatorCreationException; import org.spongycastle.util.Arrays; /** * Parsing class for an CMS Authenticated Data object from an input stream. * <p> * 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. * </p> * <p> * Example of use - assuming the first recipient matches the private key we have. * <pre> * 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("SC")); * * processDataStream(recData.getContentStream()); * * if (!Arrays.equals(ad.getMac(), recipient.getMac()) * { * System.err.println("Data corrupted!!!!"); * } * } * </pre> * Note: this class does not introduce buffering - if you are processing large files you should create * the parser with: * <pre> * CMSAuthenticatedDataParser ep = new CMSAuthenticatedDataParser(new BufferedInputStream(inputStream, bufSize)); * </pre> * where bufSize is a suitably large buffer size. */ public class CMSAuthenticatedDataParser extends CMSContentInfoParser { RecipientInformationStore recipientInfoStore; AuthenticatedDataParser authData; private AlgorithmIdentifier macAlg; private byte[] mac; private AttributeTable authAttrs; private ASN1Set authAttrSet; private AttributeTable unauthAttrs; private boolean authAttrNotRead; private boolean unauthAttrNotRead; private OriginatorInformation originatorInfo; public CMSAuthenticatedDataParser( byte[] envelopedData) throws CMSException, IOException { this(new ByteArrayInputStream(envelopedData)); } public CMSAuthenticatedDataParser( byte[] envelopedData, DigestCalculatorProvider digestCalculatorProvider) throws CMSException, IOException { this(new ByteArrayInputStream(envelopedData), digestCalculatorProvider); } public CMSAuthenticatedDataParser( InputStream envelopedData) throws CMSException, IOException { this(envelopedData, null); } public CMSAuthenticatedDataParser( InputStream envelopedData, DigestCalculatorProvider digestCalculatorProvider) throws CMSException, IOException { super(envelopedData); this.authAttrNotRead = true; this.authData = new AuthenticatedDataParser((ASN1SequenceParser)_contentInfo.getContent(BERTags.SEQUENCE)); // TODO Validate version? //DERInteger version = this.authData.getVersion(); OriginatorInfo info = authData.getOriginatorInfo(); if (info != null) { this.originatorInfo = new OriginatorInformation(info); } // // read the recipients // ASN1Set recipientInfos = ASN1Set.getInstance(authData.getRecipientInfos().toASN1Primitive()); this.macAlg = authData.getMacAlgorithm(); // // build the RecipientInformationStore // AlgorithmIdentifier digestAlgorithm = authData.getDigestAlgorithm(); if (digestAlgorithm != null) { if (digestCalculatorProvider == null) { throw new CMSException("a digest calculator provider is required if authenticated attributes are present"); } // // read the authenticated content info // ContentInfoParser data = authData.getEnapsulatedContentInfo(); CMSReadable readable = new CMSProcessableInputStream( ((ASN1OctetStringParser)data.getContent(BERTags.OCTET_STRING)).getOctetStream()); try { CMSSecureReadable secureReadable = new CMSEnvelopedHelper.CMSDigestAuthenticatedSecureReadable(digestCalculatorProvider.get(digestAlgorithm), readable); this.recipientInfoStore = CMSEnvelopedHelper.buildRecipientInformationStore(recipientInfos, this.macAlg, secureReadable, new AuthAttributesProvider() { public ASN1Set getAuthAttributes() { try { return getAuthAttrSet(); } catch (IOException e) { throw new IllegalStateException("can't parse authenticated attributes!"); } } }); } catch (OperatorCreationException e) { throw new CMSException("unable to create digest calculator: " + e.getMessage(), e); } } else { // // read the authenticated content info // ContentInfoParser data = authData.getEnapsulatedContentInfo(); CMSReadable readable = new CMSProcessableInputStream( ((ASN1OctetStringParser)data.getContent(BERTags.OCTET_STRING)).getOctetStream()); CMSSecureReadable secureReadable = new CMSEnvelopedHelper.CMSAuthenticatedSecureReadable(this.macAlg, readable); this.recipientInfoStore = CMSEnvelopedHelper.buildRecipientInformationStore(recipientInfos, this.macAlg, secureReadable); } } /** * Return the originator information associated with this message if present. * * @return OriginatorInformation, null if not present. */ public OriginatorInformation getOriginatorInfo() { return originatorInfo; } /** * Return the MAC algorithm details for the MAC associated with the data in this object. * * @return AlgorithmIdentifier representing the MAC algorithm. */ public AlgorithmIdentifier getMacAlgorithm() { return macAlg; } /** * return the object identifier for the mac algorithm. */ public String getMacAlgOID() { return macAlg.getAlgorithm().toString(); } /** * return the ASN.1 encoded encryption algorithm parameters, or null if * there aren't any. */ public byte[] getMacAlgParams() { try { return encodeObj(macAlg.getParameters()); } catch (Exception e) { throw new RuntimeException("exception getting encryption parameters " + e); } } /** * Return an AlgorithmParameters object giving the encryption parameters * used to encrypt the message content. * * @param provider the name of the provider to generate the parameters for. * @return the parameters object, null if there is not one. * @throws org.spongycastle.cms.CMSException if the algorithm cannot be found, or the parameters can't be parsed. * @throws java.security.NoSuchProviderException if the provider cannot be found. * @deprecated use getMacAlgorithm and JceAlgorithmIdentifierConverter(). */ public AlgorithmParameters getMacAlgorithmParameters( String provider) throws CMSException, NoSuchProviderException { return new JceAlgorithmIdentifierConverter().setProvider(provider).getAlgorithmParameters(macAlg); } /** * Return an AlgorithmParameters object giving the encryption parameters * used to encrypt the message content. * * @param provider the provider to generate the parameters for. * @return the parameters object, null if there is not one. * @throws org.spongycastle.cms.CMSException if the algorithm cannot be found, or the parameters can't be parsed. * @deprecated use getMacAlgorithm and JceAlgorithmIdentifierConverter(). */ public AlgorithmParameters getMacAlgorithmParameters( Provider provider) throws CMSException { return new JceAlgorithmIdentifierConverter().setProvider(provider).getAlgorithmParameters(macAlg); } /** * return a store of the intended recipients for this message */ public RecipientInformationStore getRecipientInfos() { return recipientInfoStore; } public byte[] getMac() throws IOException { if (mac == null) { getAuthAttrs(); mac = authData.getMac().getOctets(); } return Arrays.clone(mac); } private ASN1Set getAuthAttrSet() throws IOException { if (authAttrs == null && authAttrNotRead) { ASN1SetParser set = authData.getAuthAttrs(); if (set != null) { authAttrSet = (ASN1Set)set.toASN1Primitive(); } authAttrNotRead = false; } return authAttrSet; } /** * return a table of the unauthenticated attributes indexed by * the OID of the attribute. * @exception java.io.IOException */ public AttributeTable getAuthAttrs() throws IOException { if (authAttrs == null && authAttrNotRead) { ASN1Set set = getAuthAttrSet(); if (set != null) { authAttrs = new AttributeTable(set); } } return authAttrs; } /** * return a table of the unauthenticated attributes indexed by * the OID of the attribute. * @exception java.io.IOException */ public AttributeTable getUnauthAttrs() throws IOException { if (unauthAttrs == null && unauthAttrNotRead) { ASN1SetParser set = authData.getUnauthAttrs(); unauthAttrNotRead = false; if (set != null) { ASN1EncodableVector v = new ASN1EncodableVector(); ASN1Encodable o; while ((o = set.readObject()) != null) { ASN1SequenceParser seq = (ASN1SequenceParser)o; v.add(seq.toASN1Primitive()); } unauthAttrs = new AttributeTable(new DERSet(v)); } } return unauthAttrs; } private byte[] encodeObj( ASN1Encodable obj) throws IOException { if (obj != null) { return obj.toASN1Primitive().getEncoded(); } return null; } /** * This will only be valid after the content has been read. * * @return the contents of the messageDigest attribute, if available. Null if not present. */ public byte[] getContentDigest() { if (authAttrs != null) { return ASN1OctetString.getInstance(authAttrs.get(CMSAttributes.messageDigest).getAttrValues().getObjectAt(0)).getOctets(); } return null; } }