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Viber Desktop on Fedora 27 64bit: Viber cannot connect to the internet (OpenSSL error)

After updating our GNU/Linux distribution from Fedora 26 to Fedora 27, and maybe updating Viber Desktop client as well, Viber stopped working. To be more precise it could not connect to the internet any more. (Note: we used the RPM package of Viber Desktop to install Viber on our Fedora system).

Solution for the OpenSSL issue – Create a symbolic link to the missing library in the libraries folder of Viber

#Make sure all necessary packages are installed
sudo dnf install openssl openssl-devel;
#Create a symbolic link from the system installed libssl shared object to the Viber installation folder
sudo ln -s /usr/lib64/libssl.so.10 /opt/viber/lib/libssl.so;

Explanation and details – Optional Reading

To find the installation folder of Viber, we used the following command:

find / -iname viber 2>/dev/null;

that led us to the installation location of Viber which was /opt/viber/Viber.

Executing the binary in a terminal gave us the following errors

$ /opt/viber/Viber
 Qt WebEngine ICU data not found at /opt/viber/resources. Trying parent directory...
 Qt WebEngine resources not found at /opt/viber/resources. Trying parent directory...
 Qt WebEngine ICU data not found at /opt/viber/resources. Trying parent directory...
 Qt WebEngine resources not found at /opt/viber/resources. Trying parent directory...
 qt.network.ssl: QSslSocket: cannot resolve CRYPTO_num_locks
 qt.network.ssl: QSslSocket: cannot resolve CRYPTO_set_id_callback
 qt.network.ssl: QSslSocket: cannot resolve CRYPTO_set_locking_callback
 qt.network.ssl: QSslSocket: cannot resolve ERR_free_strings
 qt.network.ssl: QSslSocket: cannot resolve EVP_CIPHER_CTX_cleanup
 qt.network.ssl: QSslSocket: cannot resolve EVP_CIPHER_CTX_init
 qt.network.ssl: QSslSocket: cannot resolve sk_new_null
 qt.network.ssl: QSslSocket: cannot resolve sk_push
 qt.network.ssl: QSslSocket: cannot resolve sk_free
 qt.network.ssl: QSslSocket: cannot resolve sk_num
 qt.network.ssl: QSslSocket: cannot resolve sk_pop_free
 qt.network.ssl: QSslSocket: cannot resolve sk_value
 qt.network.ssl: QSslSocket: cannot resolve SSL_library_init
 qt.network.ssl: QSslSocket: cannot resolve SSL_load_error_strings
 qt.network.ssl: QSslSocket: cannot resolve SSL_get_ex_new_index
 qt.network.ssl: QSslSocket: cannot resolve SSLv23_client_method
 qt.network.ssl: QSslSocket: cannot resolve SSLv23_server_method
 qt.network.ssl: QSslSocket: cannot resolve X509_STORE_CTX_get_chain
 qt.network.ssl: QSslSocket: cannot resolve OPENSSL_add_all_algorithms_noconf
 qt.network.ssl: QSslSocket: cannot resolve OPENSSL_add_all_algorithms_conf
 qt.network.ssl: QSslSocket: cannot resolve SSLeay
 qt.network.ssl: QSslSocket: cannot resolve SSLeay_version
 qt.network.ssl: Incompatible version of OpenSSL
 qt.network.ssl: QSslSocket: cannot call unresolved function SSLv23_client_method
 qt.network.ssl: QSslSocket: cannot call unresolved function SSL_library_init
 QQuickItem: Cannot set activeFocusOnTab to false once item is the active focus item.
 QQuickItem: Cannot set activeFocusOnTab to false once item is the active focus item.
 qt.network.ssl: QSslSocket: cannot call unresolved function SSLv23_client_method
 qt.network.ssl: QSslSocket: cannot call unresolved function SSL_library_init
 QQuickItem: Cannot set activeFocusOnTab to false once item is the active focus item.
 qt.network.ssl: QSslSocket: cannot call unresolved function SSLv23_client_method
 qt.network.ssl: QSslSocket: cannot call unresolved function SSL_library_init

From the error we could see that the application was trying to access the functions SSLv23_client_method and SSL_library_init and it could not find them.
It was obvious that the missing functions were related to the SSL protocol, so we executed the following to make sure all necessary OpenSSL packages were installed.

sudo dnf install openssl openssl-devel;

After that we tried Viber again and gave us the same error.
So we made the assumption that Viber could not ‘see’ the installation of OpenSSL.
Then we decided to use the following command to:

  1. find all shared objects (shared libraries) of OpenSSL on our system,
  2. list all of the available functions in each shared library and
  3. identify the ones that contain the SSLv23_client_method method.
find / -iname libssl.so* -print -exec sh -c 'nm -D "$1" | grep SSLv23_client_method' _ {} \; 2>/dev/null;

Executing the command yielded the following results:

$ find / -iname libssl.so* -print -exec sh -c 'nm -D "$1" | grep SSLv23_client_method' _ {} \; 2>/dev/null;
 /usr/lib/libssl.so
 /usr/lib/libssl.so.1.1
 /usr/lib/libssl.so.10
 00027880 T SSLv23_client_method
 /usr/lib/libssl.so.1.0.2m
 00027880 T SSLv23_client_method
 /usr/lib/libssl.so.1.1.0g
 /usr/lib64/libssl.so
 /usr/lib64/libssl.so.1.1
 /usr/lib64/libssl.so.10
 000000000002dd10 T SSLv23_client_method
 /usr/lib64/libssl.so.1.0.2m
 000000000002dd10 T SSLv23_client_method
 /usr/lib64/libssl.so.1.1.0g
 /opt/viber/lib/libssl.so

From the results two libraries in the lib64 folder got our interest, so we executed ls -l on both to check them out:

$ ls -l /usr/lib64/libssl.so.10 /usr/lib64/libssl.so.1.0.2m;
lrwxrwxrwx. 1 root root 16 Nov 13 13:52 /usr/lib64/libssl.so.10 -> libssl.so.1.0.2m
-rwxr-xr-x. 1 root root 448640 Nov 13 13:52 /usr/lib64/libssl.so.1.0.2m

As you can see in the results, the two files that got us interested were in end the same file so we decided to use /usr/lib64/libssl.so.10 whose name was not tight to a minor distribution version of the library and would automatically link to any minor updates in the future.

After examining the Viber installation folder in /opt/viber/, we saw that there was a lib folder there with no SSL libraries available (even though all the QT and networking libraries were there already):

$ ls /opt/viber/lib/
libicudata.so.52 libQt5Gui.so.5 libQt5Qml.so.5 libQt5WebEngine.so.5
libicui18n.so.52 libQt5Location.so.5 libQt5QuickControls2.so.5 libQt5WebEngineWidgets.so.5
libicuuc.so.52 libQt5MultimediaQuick_p.so.5 libQt5Quick.so.5 libQt5WebSockets.so.5
libpng12.so.0 libQt5Multimedia.so.5 libQt5QuickTemplates2.so.5 libQt5Widgets.so.5
libqgsttools_p.so.1 libQt5MultimediaWidgets.so.5 libQt5QuickWidgets.so.5 libQt5XcbQpa.so.5
libqrencode.so libQt5Network.so.5 libQt5Sql.so.5
libQt5Concurrent.so.5 libQt5OpenGL.so.5 libQt5Svg.so.5 libxcb-xinerama.so.0
libQt5Core.so.5 libQt5Positioning.so.5 libQt5WebChannel.so.5
libQt5DBus.so.5 libQt5PrintSupport.so.5 libQt5WebEngineCore.so.5

Examining our OS, we saw that in the rest of the locations were the QT libraries were installed there was a copy of the libssl as well.
So we decided to make a soft symbolic link of the /usr/lib64/libssl.so.10 shared library in the Viber libraries folder.
We did two tests:

  1. Creating a symbolic link named libssl.so.10 failed.
  2. Creating a symbolic link name libssl.so succeeded and solved the issue!

The command that we used was the following:

sudo ln -s /usr/lib64/libssl.so.10 /opt/viber/lib/libssl.so;

After performing this step, Viber was working again as expected!

$ sudo ln -s /usr/lib64/libssl.so.10 /opt/viber/lib/libssl.so;
 $ /opt/viber/Viber
 Qt WebEngine ICU data not found at /opt/viber/resources. Trying parent directory...
 Qt WebEngine resources not found at /opt/viber/resources. Trying parent directory...
 Qt WebEngine ICU data not found at /opt/viber/resources. Trying parent directory...
 Qt WebEngine resources not found at /opt/viber/resources. Trying parent directory...
 QQuickItem: Cannot set activeFocusOnTab to false once item is the active focus item.
 QQuickItem: Cannot set activeFocusOnTab to false once item is the active focus item.
 QQuickItem: Cannot set activeFocusOnTab to false once item is the active focus item.
 QQuickItem: Cannot set activeFocusOnTab to false once item is the active focus item.
 QQuickItem: Cannot set activeFocusOnTab to false once item is the active focus item.
 qml: type=""
 qml: type=""
 qrc:/QML/Feed/FeedView.qml:98:5: QML ListViewEx: Binding loop detected for property "bottomMargin"
 QObject: Cannot create children for a parent that is in a different thread.
 (Parent is QObject(0x7f3f5f970520), parent's thread is QThread(0x4191210), current thread is QThread(0x515f5b0)
 Invalid SOS parameters for sequential JPEG

Success!


Replace a character in all filenames

The following command will search for files in the current directory (.) that have in their name the colon character :.
The files that match will then be renamed and all instances of the colon character : in the names will be replaced by the full stop character ..

find . -name "*:*" -execdir sh -c 'mv "$1" "${1//:/.}"' _ {} \;
  • -execdir command {} + is like -exec, but the specified command is run from the subdirectory containing the matched file, which is not normally the directory in which you started find.

Example: if you have a file named 2017-03-15 14:34:44.116002523.png then it will be renamed to 2017-03-15 14.34.44.116002523.png.


Bash: Read a file, line by line

The following script will accept from the keyboard a filename, later it will read it and process it line by line.
In this example we will just number the lines, print them and count the total number of lines in the file.

#!/bin/sh
echo Enter the Filename to process
read filename
exec<$filename
lineNumber=0
while read line
do
	lineNumber=`expr $lineNumber + 1`;
	echo $lineNumber - $line;
done
echo "Total Lines Number: $lineNumber";


Execute a command on the results of a search with the find command 1

find $LOCATION -name "$FILENAME" -exec somecommand '{}' \;

The above command will search in $LOCATION for all files named $FILENAME and apply the command that you define at somecommand.

The argument ‘{}’ inserts each file found into the somecommand syntax. The \; argument indicates the exec command line has ended — YOU MUST INCLUDE IT.


Find all files that contain a string (Get filenames) 3

Assuming you have a lot of files and you need to find all files that contain a certain string value, you can check them all automatically using the following command.

Method 1 – Using find -exec

Using the exec flag of find, you can process all files even those that their filenames contain single or double quotes or other special characters.
The following command will return a list, the list of files that contain the value ‘string’.

find . -type f -exec grep 'string' -s -l '{}' \;

The above command breaks down as follows:

  • find . -type f Find all files in current directory.
  • -exec For each match execute the following.
  • grep 'string' '{}' Search the matched file '{}' if it contains the value ‘string’.
  • -s Suppress error messages about nonexistent or unreadable files.
  • -l (lambda lower case) or --files-with-matches Suppress normal output, instead print the name of each input file from which output would normally have been printed. The scanning will stop on the first match.

To exclude binary files from matching, add the -I parameter on grep.

Method 2 – Using xargs

This method will not work for filenames that contain single quotes as it will confuse xargs.

find . -type f | xargs grep 'string' -s -l;

To exclude binary files from matching, add the -I parameter on grep.

Note: WordPress might change/replace the apostrophe to another ASCII apostrophe punctuation symbol! Make sure you use the straight apostrophe symbol or else you will not get the result expected since the behavior of grep will change. See Apostrophe on WikiPedia Here.