+#+TITLE:Ninfacyzga-01 Setup
+#+AUTHOR:Steven Baltakatei Sandoval
+#+EMAIL:baltakatei@gmail.com
+* Main Setup
+** About
+This document created by [[http://baltakatei.com][Steven Baltakatei Sandoval]] on
+~2020-10-07T18:39Z~ under a [[http://creativecommons.org/licenses/by-sa/4.0/][CC BY-SA 4.0]] license and last updated on
+~2020-10-07T23:08Z~.
+
+This document contains information regarding setup of the
+ninfacyzga-01 hardware common to all operation modes. This includes:
+
+- Raspberry OS installation
+- WiFi configuration
+- Remote SSH login configuration
+
+** Scope
+This document describes hardware and software installation steps
+common to the various environmental sensing functions of
+ninfacyzga-01.
+
+** Narrative
+The Raspberry Pi Zero W is the platform in which environment data is
+gathered, packaged, and stored for further forwarding to a remote
+repository. The Raspberry OS 10 operating system is used. The device
+may be equipped with a UPS module in order to allow it to function as
+a mobile device for short periods of time. The system may use
+executables such as ~bklog~ to append segments of observed compressed
+(~gzip~) encrypted (~age~) data to a ~tar~ archive to local disk. This
+document describes hardware and software configuration procedures
+generally required by all environment sensing operations.
+
+** Description
+*** Hardware
+**** Raspberry Pi Zero W
+See the [[https://www.raspberrypi.org/pi-zero-w/][OEM]] webpage for this product.
+**** PiZ UpTime 2.0
+See the [[https://alchemy-power.com/piz-uptime-2-0/][OEM]] webpage for this product.
+
+*** Software
+~bklog~ : A bash script that saves its stdin stream to a tar file. The
+file may be compressed by ~gzip~ and encrypted by ~age~. It is an
+executable file contained within this repository at ~exec/bklog~. It
+should be copied to ~$HOME/.local/bin~.
+
+~bkgpslog~ : A legacy bash script similar to ~bklog~ but narrower in
+scope in that it only records output from ~gpspipe~.
+
+~gzip~ : A simple command line app that compresses stdin into a
+smaller stdout stream.
+
+~age~ : A simple command line app that encrypts stdin against public
+keys specified in its options. Produces encrypted stdout. Is an
+executable file contained within this repository at ~exec/age~. It
+should be copied to ~$HOME/.local/bin~.
+
+*** Output
+**** Encryption Method
+Files produced by the bklog script are encrypted against a set of
+public keys using [[https://github.com/FiloSottile/age][~age~]], a simple command line encryption tool
+selected over ~gpg~ because of ~age~'s deliberate lack of
+configurability.
+
+The public keys are bech32 strings supplied as options to bkgpslog
+when called. The secret key should *NOT* be stored in Ninfacyzga-01.
+
+If a key pair was generated using ~age-keygen~, then it is an [[https://en.wikipedia.org/wiki/Curve25519][~X25519~]]
+key pair. See the [[https://age-encryption.org/v1][~age~ Version 1 specification]].
+
+An ~ssh-rsa~ or ~ssh-ed25519~ SSH public key string may be used instead of
+the bech32 public key string produced by ~age-keygen~ for convenience.
+
+Help information for ~age~ is available by running ~$ age --help~.
+***** Encryption Commands
+****** Encryption through ~age~
+In order to illustrate how ~bklog~ encrypts files, below is an example
+command illustrating how ~age~ may be used to encrypt a file.
+
+#+BEGIN_EXAMPLE
+$ echo "asdf" | age -r \
+age1kza7pfshy7xwygf9349zgmk7x53mquvedgw9r98qwyyqhssh830qqjzlsw \
+> "$HOME/secret_file"
+#+END_EXAMPLE
+
+The resulting ~secret-file~ is a binary blob with a plaintext header
+indicating how the blob was encrypted (which version of age was used,
+which public key was used).
+
+****** Encryption through ~bklog~
+~bklog~ may instructed to encrypt files via the ~-e~ and ~-r [pubkey
+string]~ options. An example is shown below:
+
+#+BEGIN_EXAMPLE
+$ gpspipe -r | bklog -e \
+-r age1kza7pfshy7xwygf9349zgmk7x53mquvedgw9r98qwyyqhssh830qqjzlsw \
+-r age1ce3pvzrqfcn2pc6zqzglc8ac8yjk3fzukpy08cesqjjwns53xywqmaq7xw \
+-r age1pu5usxm743sx7rf22985xv2f4s0luzv6r6yx4fa7p8c2zyvp9fvqus2xr5 \
+-o "$HOME/Location"
+#+END_EXAMPLE
+
+~bklog~ may be instructed via the ~-e~ and ~-R~ options to watch a
+directory in order to locate public key strings in its files. ~bklog~
+reads the first line of each file and interprets it as a public key
+string.
+
+In this example, the strings beginning with ~age1...~ are
+bech32-formatted public key strings. Please see the [[*Key Generation][Key Generation]]
+section for an explanation.
+
+Since ~age~ also accepts ~ssh~ public key strings, these may also be
+used if they are of the following form (no comment).
+
+: ssh-rsa AAAAB3NzaC1yc2EAAAADAQABA…AACAQDLnJbPs7CjwPT+OxXd
+
+***** Decryption Commands
+Files may be decrypted using a command similar to:
+
+#+BEGIN_EXAMPLE
+cat location.gpx.age | age -d -i key.txt > location.gpx
+#+END_EXAMPLE
+
+The version of ~age~ used to perform the encryption
+
+
+** Operating Procedures
+*** Initial Startup
+**** Physical Setup
+**** Software Setup
+***** Install Operating System
+Install Raspberry Pi OS onto an SD card image. See the Raspberry Pi
+Foundation [[https://www.raspberrypi.org/documentation/installation/installing-images/README.md][installation instructions]].
+
+Note: "Raspberry Pi OS" is the name used by the Raspberry Pi
+Foundation to refer to their operating system images to be installed
+on Raspberry Pi hardware. The change was made in order to facilitate
+education of beginners not familiar with the wordplay between
+"Raspberry" and "Debian". See [[https://www.raspberrypi.org/forums/viewtopic.php?f=66&t=275380&sid=1a468f226394ccddf4654a3d3d90cb7d#p1668466][this]] forum post made on 2020-05-28 by
+plugwash.
+
+***** Configure Wireless
+Configure WiFi in order to permit file transfer and remote
+administration. For a Raspberry Pi W, the WiFi settings may be
+programmed via a specific text file in the `boot` partition of a
+freshly installed image of Raspberry OS. Raspberry Pi Foundation
+instructions [[https://www.raspberrypi.org/documentation/configuration/wireless/headless.md][here]].
+
+In summary, create a ~wpa_supplicant.conf~ file containing the
+following text:
+#+BEGIN_EXAMPLE
+ctrl_interface=DIR=/var/run/wpa_supplicant GROUP=netdev
+update_config=1
+country=US
+
+network={
+ ssid="<Name of your wireless LAN>"
+ psk="<Password for your wireless LAN>"
+}
+#+END_EXAMPLE
+
+Replace ~<Name of your wireless LAN>~ with your WiFi network's SSID.
+
+Replace ~<Password for your wireless LAN>~ with your WiFi network's
+passphrase.
+***** Configure Remote SSH Login
+Configure SSH to permit remote administration via the command line
+interface. Raspberry Pi Foundation instructions [[https://www.raspberrypi.org/documentation/remote-access/ssh/README.md][here]].
+
+In summary, remote SSH access may be enabled upon initial startup of a
+freshly installed image of Raspberry Pi OS by making sure an empty
+file named ~ssh~ is present on the ~boot~ partition.
+
+***** Change default passphrase
+The default username is ~pi~ and the default passphrase is
+~raspberry~. Change them to something unique.
+
+: $ passwd
+
+***** Update software
+Update software with distribution repository.
+
+: $ sudo apt update
+: $ sudo apt upgrade -y
+: $ sudo apt dist-upgrade -y
+
+***** Install software
+****** ~unattended-upgrades~
+Make sure to install the ~unattended-upgrades~ package to make sure
+the latest security patches for packages are installed. See [[https://linux-audit.com/using-unattended-upgrades-on-debian-and-ubuntu/][this page]]
+for a description of how ~unattended-upgrades~ works.
+
+The configuration file is located at:
+~/etc/apt/apt.conf.d/50unattended-upgrades~ ([[https://linux-audit.com/using-unattended-upgrades-on-debian-and-ubuntu/][ref]]). Make sure that the
+following lines are present and not commented out.
+
+#+BEGIN_EXAMPLE
+Unattended-Upgrade::Automatic-Reboot "true";
+#+END_EXAMPLE
+
+****** ~syncthing~
+Install ~syncthing~ for log file transfer capability.
+
+: $ sudo apt install syncthing
+
+****** ~git~
+Install ~git~ for downloading this repository to the device.
+
+: $ sudo apt install git
+
+****** ninfacyzga-01 git repository
+Create the directory ~/git-OC/~ . Within this directory, run the
+following commands to clone the ~ninfacyzga-01~ git repository:
+: $ git clone https://gitlab.com/baltakatei/ninfacyzga-01.git
+: $ cd ninfacyzga-01
+
+Check out the ~develop~ branch (if the latest changes are desired over
+those of the ~master~ branch).
+: $ git checkout --track origin/develop
+
+****** ~age~
+Place ~age~ binary (the one compiled for ARM CPU architecture for
+Linux) in ~$HOME/.local/bin~. A copy of binary may be found within the
+~exec~ directory.
+
+***** Disable Swap File
+Since standard Raspbian 10 (Buster) install involves copying
+unencrypted file system image to SD card which is mounted by the
+Raspberry Pi, system memory may be written to disk in the form of a
+Swap file as described [[https://ideaheap.com/2013/07/stopping-sd-card-corruption-on-a-raspberry-pi/][here]]. In order to reduce the chance that
+location log data is ever written to disk, swap file functionality
+must be disabled[fn:ideaheap_20130731_disableswap].
+
+Raspbian 10 uses dphys-swapfile to manage a swap file. It may be
+disabled persistently[fn:rpf_20190702_disableswappersist] by running
+the following command:
+
+: sudo systemctl disable dphys-swapfile.service
+
+To view the status of the swap file in Raspbian 10, run ~free -m~:
+
+#+BEGIN_EXAMPLE
+pi@ninfacyzga-01:~$ free -m
+ total used free shared buff/cache available
+Mem: 432 86 36 21 309 268
+Swap: 99 0 99
+#+END_EXAMPLE
+
+After disabling the swap file and rebooting:
+
+#+BEGIN_EXAMPLE
+pi@ninfacyzga-01:~$ free -m
+ total used free shared buff/cache available
+Mem: 432 89 214 3 128 289
+Swap: 0 0 0
+#+END_EXAMPLE
+
+[fn:ideaheap_20130731_disableswap] Explanation:
+https://ideaheap.com/2013/07/stopping-sd-card-corruption-on-a-raspberry-pi/
+
+[fn:rpf_20190702_disableswappersist] Persistant disabling of swap in
+Raspbian 10 Buster:
+https://www.raspberrypi.org/forums/viewtopic.php?p=1490692&sid=5c596a124b7805d6b10dab8d3d7caf16#p1490692
+
+***** Log Transfer Configuration
+Log files may be shared to other machines via ~syncthing~. See [[https://docs.syncthing.net/][this]]
+manual for how to set up a shared folder and add Ninfacyzga-01 as a
+device. Syncthing's directory synchronization capability allows a
+remote machine to delete files from Ninfacyzga-01 by deleting from the
+shared folder that they both share.
+
+When log files are removed from Ninfacyzga-01 is not within the scope
+of this document.
+***** Key Generation
+An ~age~ encryption key may be generated like so:
+#+BEGIN_EXAMPLE
+$ umask # Gets current umask
+0022 # Note: This is the default umask for Raspbian 10
+$ umask 066 # So key.txt will have no perms except for owner (you)
+$ umask # Confirm umask set to 066
+0066
+$ age-keygen > key.txt
+Public key: age1pu5usxm743sx7rf22985xv2f4s0luzv6r6yx4fa7p8c2zyvp9fvqus2xr5
+$ ls -al key.txt
+-rw------- 1 baltakatei baltakatei 184 Jun 29 18:28 key.txt
+$ umask 0022 # Return umask to default value
+$ umask
+0022
+#+END_EXAMPLE
+
+The resulting public/private keypair data looks like:
+#+BEGIN_EXAMPLE
+$ cat key.txt
+# created: 2020-06-29T18:01:56Z
+# public key: age1pu5usxm743sx7rf22985xv2f4s0luzv6r6yx4fa7p8c2zyvp9fvqus2xr5
+AGE-SECRET-KEY-1NEUU5U2XGZGL9UYWNPU5DL99TGJJHFSN4F2E2WCCSDJJ6L5ZMLESNTVTU0
+#+END_EXAMPLE
+
+The file ~key.txt~ is not password-protected by default and should be
+secured like an SSH public key should. The ~$ umask 066~ command run
+before the ~$ age-keygen > key.txt~ command ensures ~key.txt~ will not
+be readable, writeable, or executable to anyone except the owner
+(you).
+
+*** Normal Startup
+*** Normal Operation
+*** Normal Shutdown
+*** Unscheduled Shutdown
+*** End of Life Disposal
+See [[file:../setup/README.org][Main Setup]] procedures.
+
+LiPo batteries used by the PiZ Uptime 2.0 module should be disposed of
+properly with their potential ignitability in mind, especially if they
+are not fully discharged.
+
+Consult your local municipality for its "E-Waste Disposal" (or
+equivalent) policy. Metals used in the Raspberry Pi and related
+components may be recycled.
+
+Take extra precuation if lead solder was used in assembling the
+electronics. Consumer electronics in early 21st century should use
+lead-free solder.
+
+
+
projects / EVA-2020-02.git / commitdiff