iTextSharp.text.pdf.PdfEncryption.GetEncryptionDictionary C# (CSharp) Метод

        public PdfDictionary GetEncryptionDictionary()
        {
            PdfDictionary dic = new PdfDictionary();

            if (publicKeyHandler.GetRecipientsSize() > 0) {
            PdfArray recipients = null;

            dic.Put(PdfName.FILTER, PdfName.PUBSEC);
            dic.Put(PdfName.R, new PdfNumber(revision));

            recipients = publicKeyHandler.GetEncodedRecipients();

            if (revision == STANDARD_ENCRYPTION_40) {
                dic.Put(PdfName.V, new PdfNumber(1));
                dic.Put(PdfName.SUBFILTER, PdfName.ADBE_PKCS7_S4);
                dic.Put(PdfName.RECIPIENTS, recipients);
            }
            else if (revision == STANDARD_ENCRYPTION_128 && encryptMetadata) {
                dic.Put(PdfName.V, new PdfNumber(2));
                dic.Put(PdfName.LENGTH, new PdfNumber(128));
                dic.Put(PdfName.SUBFILTER, PdfName.ADBE_PKCS7_S4);
                dic.Put(PdfName.RECIPIENTS, recipients);
            }
            else {
                dic.Put(PdfName.R, new PdfNumber(AES_128));
                dic.Put(PdfName.V, new PdfNumber(4));
                dic.Put(PdfName.SUBFILTER, PdfName.ADBE_PKCS7_S5);

                PdfDictionary stdcf = new PdfDictionary();
                stdcf.Put(PdfName.RECIPIENTS, recipients);
                if (!encryptMetadata)
                    stdcf.Put(PdfName.ENCRYPTMETADATA, PdfBoolean.PDFFALSE);

                if (revision == AES_128)
                    stdcf.Put(PdfName.CFM, PdfName.AESV2);
                else
                    stdcf.Put(PdfName.CFM, PdfName.V2);
                PdfDictionary cf = new PdfDictionary();
                cf.Put(PdfName.DEFAULTCRYPTFILTER, stdcf);
                dic.Put(PdfName.CF, cf);
                if (embeddedFilesOnly) {
                    dic.Put(PdfName.EFF, PdfName.DEFAULTCRYPTFILTER);
                    dic.Put(PdfName.STRF, PdfName.IDENTITY);
                    dic.Put(PdfName.STMF, PdfName.IDENTITY);
                }
                else {
                    dic.Put(PdfName.STRF, PdfName.DEFAULTCRYPTFILTER);
                    dic.Put(PdfName.STMF, PdfName.DEFAULTCRYPTFILTER);
                }
            }

            IDigest sh = DigestUtilities.GetDigest("SHA1");
            byte[] encodedRecipient = null;
            byte[] seed = publicKeyHandler.GetSeed();
            sh.BlockUpdate(seed, 0, seed.Length);
            for (int i=0; i<publicKeyHandler.GetRecipientsSize(); i++)
            {
                encodedRecipient = publicKeyHandler.GetEncodedRecipient(i);
                sh.BlockUpdate(encodedRecipient, 0, encodedRecipient.Length);
            }
            if (!encryptMetadata)
                sh.BlockUpdate(metadataPad, 0, metadataPad.Length);
            byte[] mdResult = new byte[sh.GetDigestSize()];
            sh.DoFinal(mdResult, 0);
            SetupByEncryptionKey(mdResult, keyLength);
            } else {
            dic.Put(PdfName.FILTER, PdfName.STANDARD);
            dic.Put(PdfName.O, new PdfLiteral(PdfContentByte.EscapeString(ownerKey)));
            dic.Put(PdfName.U, new PdfLiteral(PdfContentByte.EscapeString(userKey)));
            dic.Put(PdfName.P, new PdfNumber(permissions));
            dic.Put(PdfName.R, new PdfNumber(revision));
            if (revision == STANDARD_ENCRYPTION_40) {
                dic.Put(PdfName.V, new PdfNumber(1));
            }
            else if (revision == STANDARD_ENCRYPTION_128 && encryptMetadata) {
                dic.Put(PdfName.V, new PdfNumber(2));
                dic.Put(PdfName.LENGTH, new PdfNumber(128));

            }
            else if (revision == AES_256) {
                if (!encryptMetadata)
                    dic.Put(PdfName.ENCRYPTMETADATA, PdfBoolean.PDFFALSE);
                dic.Put(PdfName.OE, new PdfLiteral(PdfContentByte.EscapeString(oeKey)));
                dic.Put(PdfName.UE, new PdfLiteral(PdfContentByte.EscapeString(ueKey)));
                dic.Put(PdfName.PERMS, new PdfLiteral(PdfContentByte.EscapeString(perms)));
                dic.Put(PdfName.V, new PdfNumber(revision));
                dic.Put(PdfName.LENGTH, new PdfNumber(256));
                PdfDictionary stdcf = new PdfDictionary();
                stdcf.Put(PdfName.LENGTH, new PdfNumber(32));
                if (embeddedFilesOnly) {
                    stdcf.Put(PdfName.AUTHEVENT, PdfName.EFOPEN);
                    dic.Put(PdfName.EFF, PdfName.STDCF);
                    dic.Put(PdfName.STRF, PdfName.IDENTITY);
                    dic.Put(PdfName.STMF, PdfName.IDENTITY);
                }
                else {
                    stdcf.Put(PdfName.AUTHEVENT, PdfName.DOCOPEN);
                    dic.Put(PdfName.STRF, PdfName.STDCF);
                    dic.Put(PdfName.STMF, PdfName.STDCF);
                }
                stdcf.Put(PdfName.CFM, PdfName.AESV3);
                PdfDictionary cf = new PdfDictionary();
                cf.Put(PdfName.STDCF, stdcf);
                dic.Put(PdfName.CF, cf);
            }
            else {
                if (!encryptMetadata)
                    dic.Put(PdfName.ENCRYPTMETADATA, PdfBoolean.PDFFALSE);
                dic.Put(PdfName.R, new PdfNumber(AES_128));
                dic.Put(PdfName.V, new PdfNumber(4));
                dic.Put(PdfName.LENGTH, new PdfNumber(128));
                PdfDictionary stdcf = new PdfDictionary();
                stdcf.Put(PdfName.LENGTH, new PdfNumber(16));
                if (embeddedFilesOnly) {
                    stdcf.Put(PdfName.AUTHEVENT, PdfName.EFOPEN);
                    dic.Put(PdfName.EFF, PdfName.STDCF);
                    dic.Put(PdfName.STRF, PdfName.IDENTITY);
                    dic.Put(PdfName.STMF, PdfName.IDENTITY);
                }
                else {
                    stdcf.Put(PdfName.AUTHEVENT, PdfName.DOCOPEN);
                    dic.Put(PdfName.STRF, PdfName.STDCF);
                    dic.Put(PdfName.STMF, PdfName.STDCF);
                }
                if (revision == AES_128)
                    stdcf.Put(PdfName.CFM, PdfName.AESV2);
                else
                    stdcf.Put(PdfName.CFM, PdfName.V2);
                PdfDictionary cf = new PdfDictionary();
                cf.Put(PdfName.STDCF, stdcf);
                dic.Put(PdfName.CF, cf);
            }
            }
            return dic;
        }

 /**
 * Sets the certificate encryption options for this document. An array of one or more public certificates
 * must be provided together with an array of the same size for the permissions for each certificate.
 *  The open permissions for the document can be
 *  AllowPrinting, AllowModifyContents, AllowCopy, AllowModifyAnnotations,
 *  AllowFillIn, AllowScreenReaders, AllowAssembly and AllowDegradedPrinting.
 *  The permissions can be combined by ORing them.
 * Optionally DO_NOT_ENCRYPT_METADATA can be ored to output the metadata in cleartext
 * @param certs the public certificates to be used for the encryption
 * @param permissions the user permissions for each of the certicates
 * @param encryptionType the type of encryption. It can be one of STANDARD_ENCRYPTION_40, STANDARD_ENCRYPTION_128 or ENCRYPTION_AES128.
 * @throws DocumentException if the document is already open
 */
 public void SetEncryption(X509Certificate[] certs, int[] permissions, int encryptionType) {
     if (pdf.IsOpen())
         throw new DocumentException(MessageLocalization.GetComposedMessage("encryption.can.only.be.added.before.opening.the.document"));
     crypto = new PdfEncryption();
     if (certs != null) {
         for (int i=0; i < certs.Length; i++) {
             crypto.AddRecipient(certs[i], permissions[i]);
         }
     }
     crypto.SetCryptoMode(encryptionType, 0);
     crypto.GetEncryptionDictionary();
 }