Android build issues with OpenSSL on 5.0/5.1

[kviktor]

When I try to start my application on an Android phone running 5.0 or 5.1 I get the following error, on version 6.0/7.0 the application starts/works just fine. I have tried NDK r10e and Crystax, but both have the same issue.

E/art     (18856): dlopen("/data/app/org.qtproject.example-1/lib/arm/libMyName.so", RTLD_LAZY) failed: dlopen failed: cannot locate symbol "RSA_generate_key" referenced by "libMyName.so"...
D/AndroidRuntime(18856): Shutting down VM
E/AndroidRuntime(18856): FATAL EXCEPTION: main
E/AndroidRuntime(18856): Process: org.qtproject.example, PID: 18856
E/AndroidRuntime(18856): java.lang.UnsatisfiedLinkError: dlopen failed: cannot locate symbol "RSA_generate_key" referenced by "libMyName.so"...
E/AndroidRuntime(18856): 	at java.lang.Runtime.loadLibrary(Runtime.java:371)
E/AndroidRuntime(18856): 	at java.lang.System.loadLibrary(System.java:988)
E/AndroidRuntime(18856): 	at org.qtproject.qt5.android.bindings.QtLoader.loadApplication(QtLoader.java:245)
E/AndroidRuntime(18856): 	at org.qtproject.qt5.android.bindings.QtLoader.startApp(QtLoader.java:655)
E/AndroidRuntime(18856): 	at org.qtproject.qt5.android.bindings.QtActivityLoader.onCreate(QtActivityLoader.java:183)
E/AndroidRuntime(18856): 	at org.qtproject.qt5.android.bindings.QtActivity.onCreateHook(QtActivity.java:266)
E/AndroidRuntime(18856): 	at org.qtproject.qt5.android.bindings.QtActivity.onCreate(QtActivity.java:273)
E/AndroidRuntime(18856): 	at android.app.Activity.performCreate(Activity.java:5990)
E/AndroidRuntime(18856): 	at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1106)
E/AndroidRuntime(18856): 	at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2278)
E/AndroidRuntime(18856): 	at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2387)
E/AndroidRuntime(18856): 	at android.app.ActivityThread.access$800(ActivityThread.java:151)
E/AndroidRuntime(18856): 	at android.app.ActivityThread$H.handleMessage2(ActivityThread.java:1303)
E/AndroidRuntime(18856): 	at android.os.Handler.dispatchMessage(Handler.java:102)
E/AndroidRuntime(18856): 	at android.os.Looper.loop(Looper.java:135)
E/AndroidRuntime(18856): 	at android.app.ActivityThread.main(ActivityThread.java:5254)
E/AndroidRuntime(18856): 	at java.lang.reflect.Method.invoke(Native Method)
E/AndroidRuntime(18856): 	at java.lang.reflect.Method.invoke(Method.java:372)
E/AndroidRuntime(18856): 	at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:903)
E/AndroidRuntime(18856): 	at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:698)
W/ActivityManager(  585):   Force finishing activity 1 org.qtproject.example/org.my.MyNameActivity

I have these 2 in my .pro file so the library is added

ANDROID_EXTRA_LIBS += /path/to/sysroot/lib/libcrypto.so
ANDROID_EXTRA_LIBS += /path/to/sysroot/lib/libssl.so

Also checking the .so file itself the function seems to be there

./arm-linux-androideabi-4.9/prebuilt/linux-x86_64/bin/arm-linux-androideabi-readelf -all /path/to/sysroot/lib/libcrypto.so | grep RSA_generate_key
  1020: 0009c0f4  1504 FUNC    GLOBAL DEFAULT    7 RSA_generate_key_ex
  1084: 000a00fc   220 FUNC    GLOBAL DEFAULT    7 RSA_generate_key
  9625: 0009c0f4  1504 FUNC    GLOBAL DEFAULT    7 RSA_generate_key_ex
  9689: 000a00fc   220 FUNC    GLOBAL DEFAULT    7 RSA_generate_key

Any idea what might be the issue? As I see 5.1 still has a lot of users.

Also I'm using PyQt with a modified Python install (which uses that function) but it still seems weird that 5.1 fails and 6.0 works.

[sierdzio]

The problem is that Android 5 ships with a default build of old OpenSSL release (something around 1.0.0). Since these are system libs, they get picked up before your .so files. And that's why you get a missing symbol - because wrong OpenSSL was loaded by the Android system.

I did solve this issue once, but I don't remember how, I'll try to find my solution and come back here :-)

[kviktor]

I implemented my custom function using RSA_generate_key_ex instead and the application works now (I'm guessing the OpenSSL on Android 5.0 was built without deprecated functions).

This is kind of a workaround of the original issue tho, if you find your old solution please share :)

[sierdzio]

@kviktor said in Android build issues with OpenSSL on 5.0/5.1:

if you find your old solution please share :)

Uh... I just did. Turns out that the function which was missing for me was not really necessary so I removed it. So in that sense it's the same solution you used.

As far as I know there are 2 proper solutions:

• recompile Qt with custom (static) OpenSSL build and use it to build your project (make sure you only link to OpenSSL statically)
• create a custom wrapper for OpenSSL functions you need, link it statically to OpenSSL and to your app

[kviktor]

For anyone finding this thread via Google OpenSSL actually has a somewhat detailed description about the workaround: https://wiki.openssl.org/index.php/Android#Wrapper_Shared_Objects

[mkre]

@sierdzio Is there a guide for either of these two solutions? Running into this issue now for an APK I'm trying to build for an Android 5.0/5.1 device that uses QNetworkRequest to download files from the internet.

[sierdzio]

@mkre said in Android build issues with OpenSSL on 5.0/5.1:

@sierdzio Is there a guide for either of these two solutions? Running into this issue now for an APK I'm trying to build for an Android 5.0/5.1 device that uses QNetworkRequest to download files from the internet.

Option 2 (workaround) is described in the linkg @kviktor posted, just above your comment.

As for compiling Qt statically, look in Qt docs and output of ./configure --help. Please remember license (LGPL, GPL) limitations when compiling statically.