Cannot load qca-ossl in Qt5 application

2
votes

I have decided to migrate my application from Qt4 to Qt5. With Qt4 I used QCA with QCA-OSSL without any problem, but now OSSL plugin doesnt want to load.

I have compiled QCA from git://anongit.kde.org/qca.git under Qt5 with all plugins without any problem. Than I added QCA to my application (I am using CMAKE), it compiled properly, but during run it won't allow AES cipher, because OSSL plugin was not loaded.

I've searched through forums, put libqca-ossl.so into crypto directory, and copied this dir to my /usr/lib/qt/plugins also to my project and build directory but it did not help.

I will be thanful for any help or suggestion.

3
c++qtcryptographycmakeqt5
Could you please paste the exact error message of the loading issue? – lpapp
Well there is no error message during the loading. I simply test whether AES is supported with QCA::isSupported("aes128-cbc-pkcs7") and it is not supported and simply return false, so its upon me what message i will display to user. – Michal
Well, then it does not look like a plugin loading issue, but more like the plugin not supporting the feature. Choose a plugin which supports it, or make sure that the plugin is loaded. There is a boolean method for "is loaded". – lpapp

3 Answers

5
votes

Ok I get it working the whole problem was in this...
1) CMake of git://anongit.kde.org/qca.git generates config-qca.h to a QCA source directory.
2) In this file there was #define QCA_PLUGIN_SUBDIR "qca-qt5" instead of predicted "crypto"

One possible solution is:
1) Delete lib dir in QCA (if there is one from previous configuration)
2) Run CMAKE
3) Change "qca-qt5" to "crypto" in config-qca.h
4) Build the library
5) Add library to your project and then it should load all plugins properly

0
votes

A good solution, without actually fixing QCA, is, from the build directory:

cmake . -DQCA_PLUGINS_INSTALL_DIR=`qmake -query QT_INSTALL_PLUGINS`/crypto

This will install the plugins together with Qt plugins. If you don't want to install it there, you can add another path in QT_PLUGINS_PATH environment variable and then install it there, still adding the crypto directory.

0
votes

As of QCA 2.1.1 on Dec 1, 2015, on OSX:

fetch qca from the kde anongit 

brew install openssl # fixes apple's openssl deprecation error
export PATH=$PATH:/path/to/qt5/bin/qmake
cmake . -DCMAKE_PREFIX_PATH=/usr/local/opt/openssl #use the new openssl
make install