iTextSharpパスワードで保護PDF
StackOverflowに関する次の質問と回答は、適切なパスワードがないと開くことができないPDFを生成する方法を示しています。
このフレームワークを同様に使用したいのですが、ユーザーがパスワードを必要とせずにPDFを開く」ことができるように少し変更しましたが、PDFパスワードを持っている場合。
それはiTextSharpで可能ですか？
これが問題になる場合は、C＃4.0でWF 4.0カスタムアクティビティ内で作業しています。
はい、PdfEncryptor.Encrypt()、userPasswordおよびownerPasswordに渡すことができる2つのパスワードがあります。 nullをuserPasswordに渡すだけで、パスワードを指定しなくても開くことができます。
string WorkingFolder = Environment.GetFolderPath(Environment.SpecialFolder.Desktop);
string InputFile = Path.Combine(WorkingFolder, "Test.pdf");
string OutputFile = Path.Combine(WorkingFolder, "Test_enc.pdf");
using (Stream input = new FileStream(InputFile, FileMode.Open, FileAccess.Read, FileShare.Read))
{
using (Stream output = new FileStream(OutputFile, FileMode.Create, FileAccess.Write, FileShare.None))
{
PdfReader reader = new PdfReader(input);
PdfEncryptor.Encrypt(reader, output, true, null, "secret", PdfWriter.ALLOW_SCREENREADERS);
}
}
別の実装：
public static void Common_PassWordProtectPDF_Static_WithoutEmail(FileInfo[] filteredfiles, string strAgentName, string strAgentCode, string strpassword, string strEmailID, string sourcefolder, string strdestfolder, string strdestinationFileName)
{
foreach (FileInfo file in filteredfiles)
{
//string sourcePdf = Convert.ToString(ConfigurationManager.AppSettings["SourceFolder"]) + "\\" + file.Name;
//string strdestPdf = Convert.ToString(ConfigurationManager.AppSettings["DestinationFolder"]) + file.Name;
string sourcePdf = sourcefolder + "\\" + file.Name;
string strdestPdf = strdestfolder + strdestinationFileName;
using (Stream input = new FileStream(sourcePdf, FileMode.Open, FileAccess.Read, FileShare.Read))
{
//sourcePdf unsecured PDF file
//destPdf secured PDF file
using (Stream output = new FileStream(strdestPdf, FileMode.Create, FileAccess.Write, FileShare.None))
{
PdfReader pdfReader = new PdfReader(input);
X509Store store = new X509Store("My");
store.Open(OpenFlags.ReadOnly);
X509Certificate2 cert = new X509Certificate2();
RSACryptoServiceProvider csp = null;
AcroFields fields = pdfReader.AcroFields;
foreach (X509Certificate2 mCert in store.Certificates)
{
//TODO's
string strresult = mCert.GetName();
bool str123 = false;
if (strresult.Contains("Certificate name") == true)
{
csp = (RSACryptoServiceProvider)mCert.PrivateKey;
SHA1Managed sha1 = new SHA1Managed();
UnicodeEncoding encoding = new UnicodeEncoding();
byte[] data = encoding.GetBytes(file.Name);
byte[] hash = sha1.ComputeHash(data);
// Sign the hash
byte[] signature = csp.SignHash(hash, CryptoConfig.MapNameToOID("SHA1"));
if (Verify(file.Name, signature, mCert))
{
char s = pdfReader.PdfVersion;
//var pdfStamper = PdfStamper.(pdfReader, output, s, @"\0", true);
//csp.SignData(signature, true);
pdfReader.Appendable = false;
Org.BouncyCastle.X509.X509CertificateParser cp = new Org.BouncyCastle.X509.X509CertificateParser();
Org.BouncyCastle.X509.X509Certificate[] chain = new Org.BouncyCastle.X509.X509Certificate[] {
cp.ReadCertificate(mCert.RawData)};
IExternalSignature externalSignature = new X509Certificate2Signature(mCert, "SHA-1");
// var signedPdf = new FileStream(output, FileMode.Create);
// var signedPdf = PdfEncryptor.Encrypt(pdfReader, output, true, strpassword, strpassword, PdfWriter.ALLOW_PRINTING);
//char s = pdfReader.PdfVersion;
var pdfStamper = PdfStamper.CreateSignature(pdfReader, output, s, @"\", false);
PdfSignatureAppearance signatureAppearance = pdfStamper.SignatureAppearance;
byte[] USER = Encoding.ASCII.GetBytes("userpwd");
byte[] OWNER = Encoding.ASCII.GetBytes(strpassword);
Rectangle cropBox = pdfReader.GetCropBox(1);
float width = 108;
float height = 32;
// signatureAppearance.SignatureGraphic = Image.GetInstance("C:\\logo.png");
//signatureAppearance.Layer4Text = "document certified by";
//signatureAppearance.Reason = "Because I can";
//signatureAppearance.Location = "My location";
//signatureAppearance.SetVisibleSignature(new Rectangle(100, 100, 250, 150), pdfReader.NumberOfPages, "Signature");
Rectangle rect = new Rectangle(600, 100, 300, 150);
Chunk c = new Chunk("A chunk represents an isolated string. ");
rect.Chunks.Add(c);
//signatureAppearance.SetVisibleSignature(new Rectangle(100, 100, 600, 150), pdfReader.NumberOfPages, "Signature");
signatureAppearance.SetVisibleSignature(rect, pdfReader.NumberOfPages, "Signature");
// signatureAppearance.SetVisibleSignature(new Rectangle(cropBox.GetLeft(0), cropBox.GetBottom(0), cropBox.GetLeft(width), cropBox.GetLeft(height)), pdfReader.NumberOfPages, "Signature");
signatureAppearance.SignatureRenderingMode = PdfSignatureAppearance.RenderingMode.DESCRIPTION;
pdfStamper.SetEncryption(USER, OWNER, PdfWriter.AllowPrinting, PdfWriter.ENCRYPTION_AES_128);
MakeSignature.SignDetached(signatureAppearance, externalSignature, chain, null, null, null, 0, CryptoStandard.CMS);
pdfStamper.Close();
// PdfEncryptor.Encrypt(pdfReader, output, true, strpassword, strpassword, PdfWriter.SIGNATURE_EXISTS);
}
else
{
Console.WriteLine("ERROR: Signature not valid!");
}
}
}
string Password = strpassword;
}
}
}
public static byte[] Sign(string text, string certSubject)
{
// Access Personal (MY) certificate store of current user
X509Store my = new X509Store(StoreName.My, StoreLocation.CurrentUser);
my.Open(OpenFlags.ReadOnly);
// Find the certificate we’ll use to sign
RSACryptoServiceProvider csp = null;
foreach (X509Certificate2 cert in my.Certificates)
{
if (cert.Subject.Contains(certSubject))
{
// We found it.
// Get its associated CSP and private key
csp = (RSACryptoServiceProvider)cert.PrivateKey;
}
}
if (csp == null)
{
throw new Exception("No valid cert was found");
}
// Hash the data
SHA1Managed sha1 = new SHA1Managed();
UnicodeEncoding encoding = new UnicodeEncoding();
byte[] data = encoding.GetBytes(text);
byte[] hash = sha1.ComputeHash(data);
// Sign the hash
return csp.SignHash(hash, CryptoConfig.MapNameToOID("SHA1"));
}
static bool Verify(string text, byte[] signature, X509Certificate2 cert)
{
// Load the certificate we’ll use to verify the signature from a file
// X509Certificate2 cert = new X509Certificate2(certPath);
// Note:
// If we want to use the client cert in an ASP.NET app, we may use something like this instead:
// X509Certificate2 cert = new X509Certificate2(Request.ClientCertificate.Certificate);
// Get its associated CSP and public key
RSACryptoServiceProvider csp = (RSACryptoServiceProvider)cert.PublicKey.Key;
// Hash the data
SHA1Managed sha1 = new SHA1Managed();
UnicodeEncoding encoding = new UnicodeEncoding();
byte[] data = encoding.GetBytes(text);
byte[] hash = sha1.ComputeHash(data);
// Verify the signature with the hash
return csp.VerifyHash(hash, CryptoConfig.MapNameToOID("SHA1"), signature);
}