X-Git-Url: https://zdv2.bktei.com/gitweb/EVA-2020-02.git/blobdiff_plain/27a8996a799309f834378db297854a22584d7546..b6f22edba271c384d99d18ab86420a74e549e7e0:/doc/location/README.org diff --git a/doc/location/README.org b/doc/location/README.org index 92e73b7..397968f 100644 --- a/doc/location/README.org +++ b/doc/location/README.org @@ -1,7 +1,10 @@ * Location Logging This document was created by Steven Baltakatei Sandoval on -<2020-06-29 Mon 12:14> under a [[https://creativecommons.org/licenses/by-sa/4.0/][Creative Commons BY-SA 4.0 license]]. It -was updated by Steven Baltakatei Sandoval on <2020-06-29 Mon 18:39>. +~2020-06-29T12:14Z~ under a [[https://creativecommons.org/licenses/by-sa/4.0/][Creative Commons BY-SA 4.0 license]]. It +was updated by Steven Baltakatei Sandoval on ~2020-06-30T19:44Z~ +#+TITLE: Ninfacyzga-01 Manual +#+AUTHOR: Steven Baltakatei Sandoval +#+EMAIL: baltakatei@gmail.com ** Narrative Ninfacyzga-01 records (logs) its position in time and space using a [[https://en.wikipedia.org/wiki/Satellite_navigation_device][GPS receiver]]. The NMEA location data produced by the receiver is @@ -72,7 +75,7 @@ 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 +***** Encryption Commands Files may be encrypted to several recipients using a command similar to: #+BEGIN_EXAMPLE timeout "60s" gpspipe -r | gpsbabel -i nmea -f - -o gpx -F | age \ @@ -86,7 +89,7 @@ In this example, the strings beginning with ~age1...~ are bech32-formatted public key strings. -***** Decryption +***** Decryption Commands Files may be decrypted using a command similar to: #+BEGIN_EXAMPLE @@ -108,7 +111,6 @@ conflict so a simple stacking and soldering with long header pins is possible. **** Software Setup - ***** Install Executables Install Raspbian 10 Buster onto an SD card image. See the Raspberry Pi @@ -128,21 +130,84 @@ Install ~syncthing~ for log file transfer capability. Place ~age~ binary (the one compiled for ARM CPU architecture for Linux) in ~$HOME/.local/bin~. +***** Disable Swap File +Since standard Raspbian 10 (Buster) install involves copying +unencrypted file system image to SD card which is mounted by the +Raspberry Pi, system memory may be written to disk in the form of a +Swap file as described [[https://ideaheap.com/2013/07/stopping-sd-card-corruption-on-a-raspberry-pi/][here]]. In order to reduce the chance that +location log data is ever written to disk, swap file functionality +must be disabled[fn:ideaheap_20130731_disableswap]. + +Raspbian 10 uses dphys-swapfile to manage a swap file. It may be +disabled persistently[fn:rpf_20190702_disableswappersist] by running +the following command: + +: sudo systemctl disable dphys-swapfile.service + +To view the status of the swap file in Raspbian 10, run ~free -m~: + +#+BEGIN_EXAMPLE +pi@ninfacyzga-01:~$ 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 + ***** Automatic Start Configuration Edit the user cron job list with ~$ crontab -e~ to add the following lines: #+BEGIN_EXAMPLE -0 * * * * /bin/bash /path/to/bkgpslog --output $HOME/Sync/example_dir +0 * * * * /bin/bash ~/bkgpslog --output ~/dir -@reboot /bin/bash /path/to/bkgpslog --output $HOME/Sync/example_dir +@reboot /bin/bash ~/bkgpslog --output ~/dir #+END_EXAMPLE -The first line will run ~bkgpslog~ at the start of every hour. +The first line will run ~bkgpslog~ at the start of every hour and save +output files to the ~dir~ directory in your home folder. The second line will run ~bkgpslog~ when the system starts up. +~/bin/bash~ tells ~cron~ to run ~bkgpslog~ with Bash. + +If encryption and compression are required, then the appropriate +options must be added. The lines that must be added via ~$ crontab -e~ +may resemble: + +#+BEGIN_EXAMPLE +0 * * * * /bin/bash ~/bkgpslog -c -e -r age1z2...qkv6p -o ~/dir + +@reboot /bin/bash ~/bkgpslog -c -e -r age1z2...qkv6p -o ~/dir +#+END_EXAMPLE + +The ~age1z2...qkv6p~ is an ~age~ public key string. Please see the +[[*Key Generation][Key Generation]] section for an explanation. + +The options are: + +: -c : tells bkgpslog to compress output +: -e : tells bkgpslog log to encrypt output +: -r : tells bkgpslog to interpret the next argument as a pubkey string +: -o : tells bkgpslog to write output files to the directory represented +: by the next argument + ***** 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 @@ -158,7 +223,7 @@ 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 # Sets umask so key.txt will have no permissions except for owner (you) +$ umask 066 # So key.txt will have no perms except for owner (you) $ umask # Confirm umask set to 066 0066 $ age-keygen > key.txt