need to symmetric encryption in qt app

I use Qt with mingw on Windows XP.
I tried QCA but it doesn't work with Qt (app compiles but gives fatal error when trying to execute it).
I tried a compiled version of crypto++ too but it has compiling problems (many undefined reference errors).
I don't know how to get these libs to work.
please tell me a quick and easy way. I need only a symmetric encryption to encrypt and decrypt a file.

I can't believe that qca doesn't work with Qt applications. What is that fatal error that you get when executing your application?

Quote:

---

Originally Posted by lyuts

I can't believe that qca doesn't work with Qt applications. What is that fatal error that you get when executing your application?

---

Code:

---

#include <QtCrypto>
#include <QtDebug>
#include <stdio.h>
#include <QApplication>
 
int main(int argc, char **argv)
{
 
QApplication app(argc, argv);
 
char ca[1024]="abcdefg";
 
if(!QCA::isSupported("sha1")) printf("SHA1 not supported!\n");
else printf("SHA1 supported.\n");
 
QCA::Hash shaHash("sha1");
qDebug()<<shaHash.type();
shaHash.update(ca, 7);
 
return app.exec();
 
}

---

Code:

---

######################################################################
# Automatically generated by qmake (2.01a) ??*???? 16. ???? 23:25:30 2010
######################################################################
 
TEMPLATE = app
TARGET = 
DEPENDPATH += .
INCLUDEPATH += .
 
# Input
SOURCES += main.cpp
CONFIG+=crypto
CONFIG+=console

---

it compiles but says that SHA1 is not supported.
but QCA web site says: QCA has built-in support for the SHA1 and MD5 hash algorithms, and a weak random number source.
then I get a Windows error:
Attachment 4386

Did you do

Code:

---

QCA::init();

---

?

Or maybe use QCA Initializer.

thanks lyuts.
I tested that adding QCA::init(); and QCA::Initializer I; at the begining of my program.
now it says SHA1 supported. but I still get Windows error.

Run your program under GDB then and it'll tell you where the error is.

Quote:

---

Originally Posted by fatjuicymole

Run your program under GDB then and it'll tell you where the error is.

---

Code:

---

(gdb) run
Starting program: C:\Documents and Settings\xx\Desktop\qca\test\aes/debug\t.exe
 
[New thread 2824.0x1a4]
SHA1 supported.
 
Program received signal SIGSEGV, Segmentation fault.
0x10039c99 in qca2!_ZNK3QCA6Base642okEv () from f:\Qt2009.05\qt\bin\qca2.dll
(gdb)

---

what now?

Try 'backtrace' command in gdb.

Quote:

---

#0 0x10039c99 in qca2!_ZNK3QCA6Base642okEv ()
from f:\Qt2009.05\qt\bin\qca2.dll
#1 0x10026c77 in qca2!_ZN3QCA10hexToArrayERK7QString ()
from f:\Qt2009.05\qt\bin\qca2.dll
#2 0x1002afc5 in qca2!_ZN3QCA9Algorithm6changeERK7QStringS3_ ()
from f:\Qt2009.05\qt\bin\qca2.dll
#3 0x1002b14e in qca2!_ZN3QCA9AlgorithmC2ERK7QStringS3_ ()
from f:\Qt2009.05\qt\bin\qca2.dll
#4 0x1003fd50 in qca2!_ZN3QCA4HashC1ERK7QStringS3_ ()
from f:\Qt2009.05\qt\bin\qca2.dll
#5 0x004014bd in main (argc=1, argv=0x3d4d88) at main.cpp:18

---

line 18 is: QCA::Hash shaHash("sha1");

it seems that error is internal to qca2.dll. ?

Well, it might be qca2.dll's fault by maybe you are providing invalid input that make it crash. Could you paste the complete source code you compiling and running?

main.cpp

Code:

---

#include <QtCrypto>
#include <QtDebug>
#include <stdio.h>
#include <QApplication>
 
int main(int argc, char **argv)
{
 
QCA::init();
 
QApplication app(argc, argv);
 
char ca[1024]="abcdefg";
 
if(!QCA::isSupported("md5")) printf("SHA1 not supported!\n");
else printf("SHA1 supported.\n");
 
QCA::Hash shaHash("sha1");
qDebug()<<shaHash.type();
shaHash.update(ca, 7);
 
return app.exec();
 
}

---

.pro

Code:

---

######################################################################
# Automatically generated by qmake (2.01a) ??*???? 16. ???? 23:25:30 2010
######################################################################
 
TEMPLATE = app
TARGET = 
DEPENDPATH += .
INCLUDEPATH += .
 
# Input
SOURCES += main.cpp
CONFIG+=crypto
CONFIG+=console

---

Try to make ca a null terminated string and call

Code:

---

shaHash.update(ca);

---

instead of

Code:

---

shaHash.update(ca, 7);

---

I have tried it already.