Digital signature Add Source

Unit Umain;

Interface

Uses

Windows, Messages, sysutils, variants, Classes, Graphics, Controls, Forms,

Dialogs, Stdctrls;

Type

TForm1 = Class (Tform)

Button1:tbutton;

Selfile:topendialog;

Efile1:tedit;

Label1:tlabel;

Label2:tlabel;

Efile2:tedit;

Button2:tbutton;

Button3:tbutton;

Button4:tbutton;

Cbbakfile:tcheckbox;

Label3:tlabel;

Procedure Button1Click (Sender:tobject);

Procedure Button2click (Sender:tobject);

Procedure Button3click (Sender:tobject);

Procedure Button4click (Sender:tobject);

Procedure Formclose (Sender:tobject; var action:tcloseaction);

Private

{Private declarations}

Public

{Public declarations}

End

Var

Form1:tform1;

Implementation

{$R *.DFM}

Procedure Showmessbox (Pvcaptiong, pvtext:string);

Begin

MessageBox (Form1.handle, Pansichar (Pvtext), Pansichar (Pvcaptiong), 0);

End

function Readhexdz (fvfilename:string; fvhexdz:integer): Integer; Reads the specified offset address hexadecimal data

Var

Vbuffer:array of Byte; Call function back error without length specified

Vbuffer:array [0..3] of byte; Specify length

Vint:integer;

Vfs:tfilestream;

vstr:string;

Begin

Result: =-1;

Vstr:= ';

Try

vfs:= tfilestream.create (Fvfilename, Fmopenread); Open in read mode

Vfs.position:= Fvhexdz; Set Start position

Vfs.readbuffer (Vbuffer, SizeOf (Vbuffer)); Read data to Buffer

For vint:=0 to 3 do

Vstr:=inttohex (Vbuffer[vint], 2) + vstr; Get 16 in.

result:= strtoint (' $ ' +vstr);

Except

Result: =-1

End;

Vfs.free;

End

Procedure Tform1.button1click (Sender:tobject);

Begin

Self.close;

End

Procedure Tform1.button2click (Sender:tobject);

Begin

Selfile.title: = ' Please select a file containing digital signature ';

If not Selfile.execute then Exit;

Efile1.text: = Selfile.filename;

End

Procedure Tform1.button3click (Sender:tobject);

Begin

Selfile.title: = ' Please select a file to add a digital signature ';

If not Selfile.execute then Exit;

Efile2.text: = Selfile.filename;

End

Procedure Tform1.button4click (Sender:tobject);

Var

VFile1, vfile2:string;

Vbuf1,vbuf2:array [0..3] of Byte;

Vfs:tfilestream;

Vbufattr:array [0..100000] of Pansichar;

Vfile2szqmdz,

Vfile1szqmdz,//Specify the address of the digital signature

Vfile1szqmsizedz,//Specify digital signature size

Vszqmdz,//digital signature Address

vbufsize:integer;//Digital Signature Size

Vstr, Vnewstr, vnewstr2:string;

Vint:integer;

Begin

vfile1:= Trim (Efile1.text);

VFile2: = Trim (Efile2.text);

If not fileexists (vFile1) or not FileExists (vFile2) Then

Begin

Showmessbox (' message ', ' Can't find the file! ');

Exit;

End

If Cbbakfile.checked Then

CopyFile (Pansichar (VFile2), Pansichar (Extractfilename (vFile2) + '. Bak '), False);

vfile1szqmdz:= Readhexdz (VFile1, $3c) + $98; Digital Signature Address

Vfile1szqmsizedz: = Vfile1szqmdz +$4; Digital Signature Size Address

vszqmdz:= Readhexdz (VFile1, Vfile1szqmdz); Digital signature Start Position

Vbufsize: = Readhexdz (VFile1, Vfile1szqmsizedz);

Showmessbox (IntToStr (Vfile1szqmsizedz), IntToStr (vbufsize));

Exit

Try

VFS: = Tfilestream.create (VFile1, Fmopenread);

Try

Vfs.position:= Vfile1szqmdz;

Vfs.readbuffer (VBUF1, 4); The buffer where the record digital signature is located

Vfs.position:= Vfile1szqmsizedz;

Vfs.readbuffer (VBUF2, 4); Get a buffer that records the size of a digital signature

Vfs.position:= Vszqmdz;

Vfs.readbuffer (vbufattr, vbufsize); Read digital signature data to Vbufattr

Finally

Vfs.free;

End

Vfile2szqmdz: = Readhexdz (VFile2, $3c) + $98;

VFS: = Tfilestream.create (VFile2, fmopenreadwrite);

Try

Vfs.position:= Vfile2szqmdz;

vstr:= Inttohex (vfs.size, 8);

vnewstr:= Copy (Vstr, 7, 2);

vnewstr:= vnewstr + Copy (VSTR, 5, 2);

vnewstr:= vnewstr + Copy (VSTR, 3, 2);

vnewstr:= vnewstr + Copy (vstr, 1, 2);

Vnewstr2:= ';

For Vint:=1 to (length (vnewstr) div. 2) do

Vnewstr2:=vnewstr2+char (Strtoint (' $ ' +copy (Vnewstr, (vInt-1) *2+1,2)));

Vfs.writebuffer (pointer (vNewStr2) ^, 4); Write data specify the location of the digital signature

Vfs.position: = Vfile2szqmdz + $;

Vfs.writebuffer (Vbuf2, SizeOf (VBUF2)); Write data specify digital signature size

Vfs.position:= vfs.size;

Vfs.writebuffer (vbufattr, vbufsize);

Finally

Vfs.free;

End

Showmessbox (' message ', ' Add digital signature success ');

Except

Showmessbox (' Bad news ', ' Add digital signature error ');

End

End

Procedure Tform1.formclose (Sender:tobject; var action:tcloseaction);

Begin

Action:= Cafree;

End

End.

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