need to symmetric encryption in qt app

[FS Lover]

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.

[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?

[FS Lover]

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

#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();

}


################################################## ####################
# 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:
4386

[lyuts]

Did you do
QCA::init();?

Or maybe use QCA Initializer (http://delta.affinix.com/docs/qca/classQCA_1_1Initializer.html).

[FS Lover]

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.

[squidge]

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

[FS Lover]

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


(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?

[lyuts]

Try 'backtrace' command in gdb.

[FS Lover]

#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. ?

[lyuts]

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?

[FS Lover]

main.cpp

#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

################################################## ####################
# Automatically generated by qmake (2.01a) ??*???? 16. ???? 23:25:30 2010
################################################## ####################

TEMPLATE = app
TARGET =
DEPENDPATH += .
INCLUDEPATH += .

# Input
SOURCES += main.cpp
CONFIG+=crypto
CONFIG+=console

[lyuts]

Try to make ca a null terminated string and call

shaHash.update(ca);
instead of

shaHash.update(ca, 7);

[FS Lover]

I have tried it already.