OpenSSL hints

Environment
  • Ubuntu 16.04 LTS
  • OpenSSL 1.0.2g 1 Mar 2016
Download server certificate
### Show certificate
$ openssl s_client -connect host:port -showcerts
### Download certificate
$ echo | openssl s_client -connect host:port 2>&1 | sed -ne '/-BEGIN CERTIFICATE-/,/-END CERTIFICATE-/p' > server.crt.pem
2-way TLS authentication test

Say, we’ve downloaded server certificate and generated your client private key and certificate. Now we want to test if everything works:

$ openssl s_client -connect hostname:port -CAfile server.crt.pem -cert client.crt.pem -key client-private.key.pem

If you private key is protected with a password you’ll be prompted to enter the password.

 

 

 

 

Raspberry Pi: Flower Care (aka MI Flower) sensor

Environment
  • Raspberry Pi 3 Model B
Flower Care sensor

See http://www.huahuacaocao.com/product.

Looks and feels very nice:

Be aware that there are two versions of the sensor – Chinese and  international. I saw complains on internet about chinese sensor that were bricked after software upgrade when used outside of China. It is not quite clear what exactly was bricked – mobile phone app or the sensor itself.

Python demo on Raspbery Pi

Details see on GitHub.

$ git clone https://github.com/open-homeautomation/miflora.git
$ cd miflora/
$ . ./build.sh 
$ python3 setup.py build
$ sudo python3 setup.py install
$ python3 demo.py C4:7C:8D:xx:xx:xx
Getting data from Mi Flora
FW: 2.7.0
Name: Flower care
Temperature: 18.3
Moisture: 27
Light: 105
Conductivity: 59
Battery: 100

 

Raspberry Pi: installing Mosquitto MQTT broker

Environment
  • Raspberry Pi 3 Model B

Taken from: YouTube.

Installation
$ sudo apt-get update
$ sudo apt-get dist-upgrade
### Install mosquitto
$ sudo apt-get install mosquitto
### Install mosquitto clients
$ sudo apt-get install mosquitto-clients
Testing
### Console 1
$ mosquitto_sub -t "hellomosquitto"

### Console 2
$ mosquitto_pub -t "hellomosquitto" -m "Hello, Mosquitto!"

### Console 1 will print
Hello, Mosquitto!