Digital Signature
Printed From: Debenu Quick PDF Library - PDF SDK Community Forum
Category: For Users of the Library
Forum Name: I need help - I can help
Forum Description: Problems and solutions while programming with the Debenu Quick PDF Library and Debenu PDF Viewer SDK
URL: http://www.quickpdf.org/forum/forum_posts.asp?TID=3995
Printed Date: 25 Apr 24 at 8:04AM
Software Version: Web Wiz Forums 11.01 - http://www.webwizforums.com
Topic: Digital Signature
Posted By: MauricioPt
Subject: Digital Signature
Date Posted: 31 Oct 22 at 2:50PM
Hi,
i have translated the sample source code from C# and VB from here :
https://www.debenu.com/kb/advanced-options-signing-pdf-files/
into Delphi language.
uses
Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants, System.Classes, Vcl.Graphics, Vcl.Controls, Vcl.Forms, Vcl.Dialogs, Vcl.StdCtrls, DebenuPDFLibrary,
cyStrUtils, cyDebenuPDFLibrary, idGlobal, IdCoderMIME,
ssl_const, ssl_types, ssl_init, ssl_err, ssl_evp, ssl_bio, ssl_pem, ssl_engine, ssl_x509, ssl_pkcs7, ssl_pkcs12, ssl_rsa;
procedure TFrmPrinDemoPdf.SignDataWithPfxFile(const AFileName, Password: String; const DataToSign: AnsiString; var Result: ansistring);
var
LM: TMemoryStream;
AnsiPassword: AnsiString;
PAnsiPassword: PAnsiChar;
B: PBIO;
P12: PPKCS12;
// Pfx extaction :
pCertificate: PX509;
pkey: PEVP_PKEY;
ca: PSTACK_OF_X509;
md: PEVP_MD;
// Hash :
mdctx: EVP_MD_CTX;
AnsiDataToHash: AnsiString;
LengthAnsiDataToHash: integer;
HashBuffer: Array of AnsiChar; // Array [0..4095] of AnsiChar;
HashBufferF: Array [0..4095] of AnsiChar;
c, HashSize: integer;
// Sign :
AnsiDataToSign: AnsiString;
LengthAnsiDataToSign: integer;
ppKeyCtx: PPEVP_PKEY_CTX;
pEngin: PENGINE;
SignBuffer: Array of AnsiChar; // Array [0..4095] of AnsiChar;
SignSize: cardinal;
// Test
bp, b64, mbp: PBIO;
signFile: string;
_RSA: PRSA;
// PKCS7 :
_pPKCS7: PPKCS7;
_flags: integer;
_certs: PSTACK_OF;
InputBioFile, OutputBioFile: PBIO;
aIdBytes: TIdBytes;
pmdctx: PEVP_MD_CTX;
// f: file;
begin
Result := '';
B := nil;
P12 := nil;
pkey := Nil;
pCertificate := Nil;
ca := Nil;
LM := nil;
AnsiPassword := Copy(Password, 1, Length(Password));
PAnsiPassword := PAnsichar(AnsiPassword);
//ShowMessage( intToStr(Length(AnsiPassword)) );
// raise exception SSL_InitLib;
SSL_InitPEM;
SSL_InitERR;
SSL_InitBIO;
SSL_InitEVP;
// Ajouté !
//SSL_InitRSA;
SSL_InitPKCS7;
//SSL_InitX509;
//SSL_InitPKCS12;
// Exception SSL_InitENGINE;
SSL_InitX509;
SSL_InitPKCS12;
// Exception ENGINE_load_builtin_engines;
OpenSSL_add_all_ciphers;
OpenSSL_add_all_digests;
// OpenSSL_add_all_algorithms;
ERR_load_crypto_strings;
try
LM := TMemoryStream.Create;
LM.LoadFromFile(AFileName);
except
LM.Free;
Exit;
end;
try
B := BIO_new_mem_buf(LM.Memory, LM.Size);
if not Assigned(B) then
begin
Exit;
end;
// * Créer le PPKCS12 * //
try
P12 := ssl_pkcs12.d2i_PKCS12_bio(B, nil);
if Assigned(P12) then
begin
try
// * Vérifier le mot de passe (!!! Ne fonctionne que si nous avons appelé tous les SSL_Init + OpenSSL_add !!!) * //
if PKCS12_verify_mac(P12, PAnsiChar(AnsiPassword), Length(AnsiPassword)) = 1 then // 0 s'il y a un pb ... PAnsiChar(AnsiPassword) ou PAnsiPassword ...
begin
// * Récupérer le certificat X509 * //
PKCS12_parse(p12, PAnsiChar(AnsiPassword), @pkey, @pCertificate, @ca); // PAnsiChar(AnsiPassword) ou PAnsiPassword ...
if Assigned(pCertificate) then
begin
// INFO : ShowMessage(pCertificate^.name);
end;
// * Sign * //
if Assigned(pkey) and CBSignProcessPassthroughSHA1.Checked then
try
// Create an SHA-1 hash of the file data //
md := EVP_get_digestbyname('SHA1'); // EVP_sha256;
// Pas besoin ... New(mdctx);
if EVP_SignInit(@mdctx, md) = 1 then // Ou directement EVP_SignInit(@md_ctx, EVP_SHA1);
try
// SSL_CheckError;
AnsiDataToHash := DataToSign;
LengthAnsiDataToHash := Length(AnsiDataToHash);
// Tableau dynamique :
if EVP_SignUpdate(@mdctx, PAnsiChar(AnsiDataToHash), LengthAnsiDataToHash) = 1 then
begin
SetLength(HashBuffer, EVP_PKEY_size(pKey));
if EVP_SignFinal(@mdctx, PAnsiChar(HashBuffer), HashSize, pkey) = 1 then // HashSize = 256 cars
begin
Result := '';
c := 0;
while c < HashSize do
begin
Result := Result + HashBuffer[c];
inc(c);
end;
MemLogs.Lines.Add('Data to SHA1 : "' + Copy(AnsiDataToHash, 1, 20) + '..."');
MemLogs.Lines.Add('HASH result : "' + Result + '"');
string_Savetofile(Result, 'D:\_DELPHI XE10.2\_TEST SIGN\_DEBUG\QuickPDF\Certificat\SetSignProcessPassthrough 04 hash result.txt', TEncoding.ANSI);
end;
end;
finally
end;
finally
end;
// PKCS 7 //
if Assigned(pkey) and CBSignProcessPassthroughPkcs7.Checked then
try
MemLogs.Lines.Add('HASH to sign (PKCS7) : "' + string_LoadFromfile('D:\_DELPHI XE10.2\_TEST SIGN\_DEBUG\QuickPDF\Certificat\SetSignProcessPassthrough 04 hash result.txt', TEncoding.ANSI) + '"');
// Range du pdf ! InputBioFile := BIO_new_file('D:\_DELPHI XE10.2\_TEST SIGN\_DEBUG\QuickPDF\Certificat\SetSignProcessPassthrough.data_to_sign.txt','rb');
InputBioFile := BIO_new_file('D:\_DELPHI XE10.2\_TEST SIGN\_DEBUG\QuickPDF\Certificat\SetSignProcessPassthrough 04 hash result.txt','rb'); // TODO: charger via la variable Result //
OutputBioFile := BIO_new_file('D:\_DELPHI XE10.2\_TEST SIGN\_DEBUG\QuickPDF\Certificat\SetSignProcessPassthrough 05 pkcs7 signature.p7m','wb');
_certs := nil; // := ca fait augmenter la taille du pdf
_flags := ssl_const.PKCS7_NOATTR;// or ssl_const.PKCS7_STREAM; // _flags info: If "PKCS7_NOCERTS" is set, the signer's certificate will not be included in the PKCS7 structure
_pPKCS7 := ssl_pkcs7.PKCS7_sign(pCertificate, pkey, _certs, InputBioFile, _flags); // il faut appeler SSL_InitPKCS7 avant !
ssl_pkcs7.i2d_PKCS7_bio_stream(OutputBioFile, _pPKCS7, InputBioFile, _flags); // SMIME_write_PKCS7( OutputBioFile, p7, InputBioFile, flags );
PKCS7_free(_pPKCS7);
BIO_Free(InputBioFile);
BIO_Free(OutputBioFile); // Le fichier est écrit une fois le free effectué !
Result := string_LoadFromfile('D:\_DELPHI XE10.2\_TEST SIGN\_DEBUG\QuickPDF\Certificat\SetSignProcessPassthrough 05 pkcs7 signature.p7m', TEncoding.ANSI); // TODO: Sauvegarder dans la variable Result //
MemLogs.Lines.Add('Sign (PKCS7) result : "' + Result + '"');
finally
end;
end
else begin
// ERR_get_error;
// ERR_print_errors(B);
end;
finally
PKCS12_free(P12);
end;
end;
finally
BIO_free(B);
end;
finally
FreeAndNil(LM);
end;
end;
procedure TFrmPrinDemoPdf.BtnSetSignProcessPassthroughClick(Sender: TObject);
var
FichierEntreePdf, FichierSortiePdf: string;
DataToSign, ResultatSignature, LoadSignature: AnsiString;
FichierImage, FichierCert, SignatureFieldName, Reason, Location, ContactInfo: string;
PfxPassword: AnsiString;
PDFLibrary: TDebenuPDFLibrary;
UnlockResult, LoadResult, SignProcessID, TestByteSignature, SignatureByteLength, X, Rslt: Integer;
hashRange: array[0..7] of integer;
LM: TMemoryStream;
filedata: TBytes;
filedataLength: Integer;
BytesRead: Integer;
Hex: string;
begin
MemLogs.Lines.Clear;
FichierCert := 'c:\certificate.pdf';
PfxPassword := '';
FichierEntreePdf := 'c:\input.pdf';
FichierSortiePdf := 'c:\signed.pdf';
// Estimate how much space we need for the signature by first signing some random data
DataToSign := 'calc need bytes';
SignDataWithPfxFile(FichierCert, PfxPassword, DataToSign, ResultatSignature);
TestByteSignature := Length(ResultatSignature);
MemLogs.Lines.Add('Bytes de la signature : ' + intToStr(TestByteSignature) );
PDFLibrary := TDebenuPDFLibrary.Create;
UnlockResult := PDFLibrary.UnlockKey('my licence key');
if UnlockResult = 0 then
begin
PDFLibrary.Free;
Exit;
end;
try
Rslt := 0; // Signé ?
SignatureFieldName := 'FIELD_SIGN';
FichierImage := 'c:\image.png';
Reason := 'DEBUGGING ...';
Location := 'PORTUGAL';
ContactInfo := 'Mauricio';
// SignatureByteLength := TestByteSignature * 2 + 512;
// Number of bytes to reserve for the signature placeholder. We need double the bytes because they will will be stored in hex format, and we add 512 bytes extra margin :
// Non car le fonction SetSignProcessPassthrough duplique déjà les bytes comme indiqué ici:
SignatureByteLength := TestByteSignature + 256; // SetSignProcessPassthrough already duplicates bytes !
SignProcessID := PDFLibrary.NewSignProcessFromFile(FichierEntreePdf, '');
if SignProcessID <> 0 then
try
// In this mode, the PDF is prepared using a placeholder for the signature data. The user can then replace this placeholder with the signature data of their choice
// using the GetSignProcessByteRange function to determine the byte range that the signature hashing should be calculated over.
// The length in bytes of the raw binary signature data. This value will be doubled when allocating the space in the PDF as the signature data should be written using hex encoding (two characters per raw byte).
Rslt := PDFLibrary.SetSignProcessPassthrough(SignProcessID, SignatureByteLength);
if Rslt = 1 then
begin
PDFLibrary.SetSignProcessInfo(SignProcessID, Reason, Location, ContactInfo);
PDFLibrary.SetSignProcessField(SignProcessID, SignatureFieldName);
PDFLibrary.SetSignProcessFieldBounds(SignProcessID, 100, 600, 200, 100);
if FichierImage <> '' then
PDFLibrary.SetSignProcessFieldImageFromFile(SignProcessID, FichierImage, 0);
PDFLibrary.EndSignProcessToFile(SignProcessID, FichierSortiePdf); // Sauvegarde le fichier sur le disque
Rslt := PDFLibrary.GetSignProcessResult(SignProcessID);
if Rslt = 1 then
if FileExists(FichierSortiePdf) then
begin
// Byte ranges //
for X := 0 to 7 do
begin
hashRange[X] := PDFLibrary.GetSignProcessByteRange(SignProcessID, X + 1);
MemLogs.Lines.Add('hashRange[' + intToStr(X) + '] : ' + intToStr(hashRange[X]) );
// hashRange[4] hashRange[5] hashRange[6] et hashRange[7] à 0
end;
// Read the file data into a byte array, missing out the placeholder for the signature data //
filedataLength := hashRange[1] + (hashRange[3]); // Visual Basic sample do -1 but not C# sample ... := hashRange[1] + (hashRange[3] - 1);
SetLength(filedata, filedataLength);
try
LM := TMemoryStream.Create;
LM.LoadFromFile(FichierSortiePdf);
LM.Seek(hashRange[0], TSeekOrigin.soBeginning); // Seek() Déplace la position en cours dans le flux de Offset octets par rapport à la position de départ spécifiée par Origin.
BytesRead := LM.Read(filedata, 0, hashRange[1]); // La méthode Read permet de lire le contenu du flux mémoire dans un tampon en partant de la position en cours
LM.Seek(hashRange[2], TSeekOrigin.soBeginning);
BytesRead := LM.Read(filedata, hashRange[1], hashRange[3]);
// Sign the file data (generates an SHA-1 hash and signs that hash) /
SetString(DataToSign, PAnsiChar(filedata), filedataLength);
SignDataWithPfxFile(FichierCert, PfxPassword, DataToSign, ResultatSignature);
// Convert the signature to hex format //
Hex := AnsistringToHex(ResultatSignature); // Length(Hex) = 2 x Length(ResultatSignature) = 512 ...
// Write the signature into the placeholder //
LM.Seek(hashRange[1] + 1, TSeekOrigin.soBeginning);
filedata := BytesOf(Hex);
LM.Write(filedata, length(filedata));
LM.SaveToFile(FichierSortiePdf);
finally
LM.Free;
end;
end;
end;
finally
PDFLibrary.ReleaseSignProcess(SignProcessID); // Releases a signature process from memory
end;
if Rslt = 1 then
ShowMessage('Signé');
finally
PDFLibrary.Free;
end;
MemLogs.SelStart := 0;
MemLogs.SelLength := 0;
end;
I have written SignDataWithPfxFile() function with open_ssl library.
I can see the certificate but not Acrobat says that the document has been modified.
Any help will be appreciate.
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Replies:
Posted By: MauricioPt
Date Posted: 31 Oct 22 at 2:52PM
I can see the certificate but Acrobat says that the document has been modified.
Any help will be appreciate.
|
Posted By: samukinha
Date Posted: 23 Nov 22 at 6:08PM
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Hi Mauricio What is your Debenu version? I have 13.12 version. I don't have binaries for Delphi 11 to test, if you can send me... Regards
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Posted By: samukinha
Date Posted: 25 Nov 22 at 2:22PM
|
Hi Mauricio What is your Debenu version? I have 13.12 version. I don't have binaries for Delphi 11 to test, if you can send me... Regards
|
Posted By: MauricioPt
Date Posted: 28 Nov 22 at 11:49AM
I have QuickPdf v15.11 licensed.
I can't send Delphi binaries.
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