All posts by Max Chinni

Override DNS new release (v5.1.0)

Changelog

  • Make everything faster
  • New feature: the app can use DNS servers listening on alternate ports (ur0011)
  • New feature: the app can now be activated as a Device Administrator (ur0020)
  • New feature: support for 64-bit architectures in setools-android
  • New feature: auto clear notification (ur0031)
  • New feature: custom notification priority (ur0032)
  • Migrate root library from RootCommands to libsuperuser
  • Add OpenDNS on port 443 in the predefined list of available servers
  • Ask again for root permissions after an upgrade
  • Add iptables cleanup procedure in the Advanced settings
  • Upgrade gradle, EventBus, setools-android, android-rate, showcaseview, dashclock-api
  • New library: vntnumberpickerpreference
  • bugfix when busybox replaces toolbox/toybox
  • bugfixes

Override DNS is #malicious-harmful!?

Hi guys,
my app is temporarily out of the Play Store. I hope it’s really a temporary thing.

It seems that my last beta (beta78), the one available only to the beta testers, was not compliant to the 4.4 section of the Developer Distribution Agreement. But let me explain in the right order.

50 minutes ago I received an e-mail from the Google Play Support. It was notifying me of some kind of violation. The e-mail was referring to the app: “Virtual Button ROOT MENU” (package ID jp.ne.neko.freewing.VirtualButtonRootMenu).
It seems that that app, which disables SELinux, violates the Developer Distribution Agreement

Don’t transmit or link to… items that may introduce security vulnerabilities to or harm user devices, apps, or personal data.

OK.

I’m serious it wasn’t some kind of phishing, they simply sent me the right notice but referring to someone else.

My latest beta has an advanced option which, if chosen, temporary lowers the device security by disabling SELinux on the device. It applies the DNS and brings SELinux back again. So it seems I’m guilty.

And now

Disabling SELinux is not approved by the Play Store.

In my humble opinion it was not so obvious, but anyway, I repackaged a stable release and a beta without the SELinux thing. I’m waiting to see my app online again.

Install UBCD on a bootable USB stick

Ultimate Boot CD was a really good tool when I worked as a sysadmin and I thought it was a good thing to keep a USB stick around.

Download UBCD

There are several options to download a copy of UBCD iso, all listed on the dedicated page. A good way is to use torrent (here’s the magnet link).

Indetify your USB device

Please be careful here, if you are wrong, you are going to delete the wrong disk.
I’m not responsible of any data you loose.

There are few ways to detect the right USB device, I usually take a look do dmesg output

$ dmesg | grep -A8 'Direct-Access'
[  844.712601] scsi 6:0:0:0: Direct-Access     Generic  Flash Disk       8.07 PQ: 0 ANSI: 2
[  844.713050] sd 6:0:0:0: Attached scsi generic sg2 type 0
[  844.716347] sd 6:0:0:0: [sdc] 15663104 512-byte logical blocks: (8.01 GB/7.46 GiB)
[  844.716774] sd 6:0:0:0: [sdc] Write Protect is off
[  844.716780] sd 6:0:0:0: [sdc] Mode Sense: 03 00 00 00
[  844.716969] sd 6:0:0:0: [sdc] No Caching mode page found
[  844.716972] sd 6:0:0:0: [sdc] Assuming drive cache: write through
[  844.719175]  sdc: sdc1
[  844.720364] sd 6:0:0:0: [sdc] Attached SCSI removable disk

In this case I’m sure that the device is sdc because I’ve only one disk with 8GB of storage.

I’ll use sdc in this document, you should use your device name, it’s really important.

Format the USB stick

Be sure that the OS you are running have not automatically mounted any previous partition on the stick:

$ sudo umount /dev/sdc*

Then you could use GParted or do it manually as I like.

$ sudo parted -s /dev/sdc mklabel msdos
$ sudo parted -s /dev/sdc mkpart primary fat32 0 700
$ sudo parted -s /dev/sdc set 1 boot on
$ sudo mkfs.vfat -F32 /dev/sdc1
$ sudo parted -s /dev/sdc print
Model: Generic Flash Disk (scsi)
Disk /dev/sdc: 8020MB
Sector size (logical/physical): 512B/512B
Partition Table: msdos
Disk Flags:

Number  Start  End    Size   Type     File system  Flags
 1      512B   700MB  700MB  primary               boot, lba

Extract ISO data on a folder

$ mkdir ubcd534
$ sudo mount -o loop,ro ubcd534.iso /mnt/misc/
$ rsync -avr /mnt/misc/ ubcd534/
$ sudo umount /mnt/misc

Copy ISO data to USB

$ sudo mount /dev/sdc1 /mnt/misc/
$ sudo rsync -rtv ubcd534/ /mnt/misc/
$ sudo umount /dev/sdc1

Make the USB device bootable

$ cd ubcd534/ubcd/tools/linux/ubcd2usb
$ chmod +x syslinux
$ sudo ./syslinux -s -d /boot/syslinux -i /dev/sdc1

Statically compile redis 3.0.2 on CentOS 5 (RHEL 5)

How to statically compile redis 3.0.2 on CentOS 5 (RHEL 5)

wget http://download.redis.io/releases/redis-3.0.2.tar.gz
wget http://prdownloads.sourceforge.net/tcl/tcl8.5.18-src.tar.gz

Install tcl8.5

tar xfz tcl8.5.18-src.tar.gz
cd tcl8.5.18/unix
./configure
make
make test
make install

Compile redis

Statically linked binaries

make CFLAGS="-static" EXEEXT="-static" LDFLAGS="-I/usr/local/include/"

Dynamically linked binaries

make LDFLAGS="-I/usr/local/include/"

How to manually install redis

cd src/
cp redis-{server,cli} /usr/local/bin/
chown root: /usr/local/bin/redis-{server,cli}
chmod 755 /usr/local/bin/redis-{server,cli}
mkdir /{var,etc}/redis /var/redis/6379
chmod 775 /{var,etc}/redis
cp redis.conf /etc/redis/6379.conf
sed -i 's/daemonize no/daemonize yes/' /etc/redis/6379.conf
sed -i 's,pidfile /var/run/redis.pid,pidfile /var/run/redis_6379.pid,' /etc/redis/6379.conf
sed -i 's/^# bind 127.0.0.1/bind 127.0.0.1/' /etc/redis/6379.conf
sed -i 's,logfile "",logfile "/var/log/redis_6379.log",' /etc/redis/6379.conf
sed -i 's,dir ./,dir /var/redis/6379,' /etc/redis/6379.conf

Useful aptitude commands

A simple list of installed packages

max@wonko:~$ aptitude search '~i' -F '%p'

Search for installed packages from the testing repo

max@wonko:~$ aptitude versions '~i ~Atesting' --group-by=none

Finding why a package is installed

I found fonts-font-awesome in my headless server, but there’s a reason

max@wonko:~$ aptitude why fonts-font-awesome
i   owncloud Depends fonts-font-awesome

Select packages that were removed but not purged

max@wonko:~$ aptitude search '~c'

Search in the package description

max@wonko:~$ aptitude search '~d"web browser"'

Upgradable packages

max@wonko:~$ aptitude search '~U'