Examples with StandardSecurityHandler com.tom_roush.pdfbox.pdmodel.encryption.StandardSecurityHandler used on opensource projects

Example 1 with StandardSecurityHandler

use of com.tom_roush.pdfbox.pdmodel.encryption.StandardSecurityHandler in project PdfBox-Android by TomRoush.

the class TestSymmetricKeyEncryption method encrypt.

// encrypt with keylength and permission, save, check sizes before and after encryption
// reopen, decrypt and return document
private PDDocument encrypt(int keyLength, boolean preferAES, int sizePriorToEncr, PDDocument doc, String prefix, AccessPermission permission, String userpassword, String ownerpassword) throws IOException {
    StandardProtectionPolicy spp = new StandardProtectionPolicy(ownerpassword, userpassword, permission);
    spp.setEncryptionKeyLength(keyLength);
    spp.setPreferAES(preferAES);
    // This must have no effect and should only log a warning.
    doc.setAllSecurityToBeRemoved(true);
    doc.protect(spp);
    File pdfFile = new File(testResultsDir, prefix + keyLength + "-bit-" + (preferAES ? "AES" : "RC4") + "-encrypted.pdf");
    doc.save(pdfFile);
    doc.close();
    long sizeEncrypted = pdfFile.length();
    Assert.assertTrue(keyLength + "-bit " + (preferAES ? "AES" : "RC4") + " encrypted pdf should not have same size as plain one", sizeEncrypted != sizePriorToEncr);
    // test with owner password => full permissions
    PDDocument encryptedDoc = PDDocument.load(pdfFile, ownerpassword);
    Assert.assertTrue(encryptedDoc.isEncrypted());
    Assert.assertTrue(encryptedDoc.getCurrentAccessPermission().isOwnerPermission());
    // Older encryption allows to get the user password when the owner password is known
    PDEncryption encryption = encryptedDoc.getEncryption();
    int revision = encryption.getRevision();
    if (revision < 5) {
        StandardSecurityHandler standardSecurityHandler = new StandardSecurityHandler();
        int keyLengthInBytes = encryption.getVersion() == 1 ? 5 : encryption.getLength() / 8;
        byte[] computedUserPassword = standardSecurityHandler.getUserPassword(ownerpassword.getBytes(Charsets.ISO_8859_1), encryption.getOwnerKey(), revision, keyLengthInBytes);
        assertEquals(userpassword.substring(0, 32), new String(computedUserPassword, Charsets.ISO_8859_1));
    }
    encryptedDoc.close();
    // test with user password => restricted permissions
    encryptedDoc = PDDocument.load(pdfFile, userpassword);
    Assert.assertTrue(encryptedDoc.isEncrypted());
    Assert.assertFalse(encryptedDoc.getCurrentAccessPermission().isOwnerPermission());
    assertEquals(permission.getPermissionBytes(), encryptedDoc.getCurrentAccessPermission().getPermissionBytes());
    return encryptedDoc;
}