OpenSSL for Android support

[Unix One]

@mateczek Thank your for this. Your script succeeds in producing the libcrypto.so and libssl.so. However, when I deploy them along with my app to the phone, I get

W libmyapp.so: (null):0 ((null)): qt.network.ssl: QSslSocket: cannot call unresolved function SSLv23_client_method
W libmyapp.so: (null):0 ((null)): qt.network.ssl: QSslSocket: cannot call unresolved function SSL_CTX_new
W libmyapp.so: (null):0 ((null)): qt.network.ssl: QSslSocket: cannot call unresolved function SSL_library_init
W libmyapp.so: (null):0 ((null)): qt.network.ssl: QSslSocket: cannot call unresolved function ERR_get_error
W libmyapp.so: (null):0 ((null)): qt.network.ssl: QSslSocket: cannot call unresolved function ERR_get_error

The network calls do not succeed and I'm guessing those errors are the reason. What am I missing?

[Unix One]

@Eddie It looks like per the readme you pasted in the comment, that won't work with any recent NDK versions (r10e is over 3 years old, and the oldest one Google still provides). I was trying to get it to work a reasonably recent version.

[Unix One]

A couple of updates:

• I tried compiling openssl-1.1.0h (current stable version) against the old android ndk (r10e) because people seem to have reported that working. Well, it compiled, but it didn't work in the app. The errors were similar to the ones I got with @mateczek's script. I also noticed
  qt.network.ssl: Incompatible version of OpenSSL
  error, but that could have been present with @mateczek's result too, and I could have just missed it. So, it resulted in a similar output.
• Then I decided to give openssl-1.0.2o (current stable LTS version) a try. To my astonishment, it compiled, and it worked in the app!

So, the conclusion is:

• use openssl-1.0.x LTS version, until it's supported
• use android-ndk-r10e, until it's supported
• use these instructions

The remaining question: is this a known issue? Is there a bug to update openssl support to more recent openssl and android ndk versions?

For reference, I run OpenSUSE Tumbleweed and keep it updated. Qt Creator 4.7.0. Qt 5.11.1. I'm happy to test and provide additional information if anyone has any ideas.

[Pablo J. Rogina]

@Unix-One said in OpenSSL for Android support:

The remaining question: is this a known issue? Is there a bug to update openssl support to more recent openssl and android ndk versions?

Checking Qt's source code, you'll find that OpenSSL 1.1.x is not yet supported...

...
if (!_q_SSLeay || q_SSLeay() >= 0x10100000L) {
        // OpenSSL 1.1 has deprecated and removed SSLeay. We consider a failure to
        // resolve this symbol as a failure to resolve symbols.
        // The right operand of '||' above is ... a bit of paranoia.
        delete libs.first;
        delete libs.second;
        qCWarning(lcSsl, "Incompatible version of OpenSSL");
        return false;
    }
...

[SGaist]

OpenSSL 1.1 has a backend in Qt since Qt 5.10 but you have to build Qt by hand in order to use it currently.

[Unix One]

@Pablo-J-Rogina @SGaist that is good to know - would have been useful information on the instructions page that would potentially save developers a lot of time. I might update the wiki with the basic steps for minimum android packaging and deployment (given I find enough time of course).

Thank you all for your help.

[AlfredoC]

Hi,
I had a lot of trouble with openssl and qt with android too.
So I wrote a post how to solve the problems.
Hope this helps.

[Knox]

@AlfredoC concerning your guide, i have setup a VM so that i could build the apk in ubuntu (i have given up doing it in windows) ubuntu 10.10 runs openssl v 1.1.1. as in your guide says that that wont do, how actually do i use 1.0.2p? can i install it directly? or do i just extract it? im sorry very noob question here.

[AlfredoC]

you have to download the openssl source, compile it for Android as described and copy the 2 libraries to your project.
If you trust me, you can download the precompiled libs here ;-)

[ekkescorner]

@AlfredoC hint to your blog post: Qt 5.12 now uses NDK r18b

[10Exahertz]

@Alfredo Thank you for the blog post but I'm still having trouble, when I get to the "make depend" part it gives me this error:

"GCC, does not understand command line option "-mandroid""
Based on a google search I'm not using the right GCC, im using (x86) and not the android one in the NDK?

Im confused as to how to do this properly.

[ekkescorner]

have not tried yet, but this looks great: https://github.com/akontsevich/openssl-android-build

[10Exahertz]

This one worked like a charm, took 10 min overall.

https://github.com/ekke/android-openssl-qt