Email security with Google Workspace

TL;DR; What records needs to be added to DNS? v=spf1 include:_spf.google.com -all v=DKIM1; k=rsa; p=MIIBI...6lwIDAQAB google._domainkey v=DMARC1; p=reject; rua=mailto:[email protected] default._bimi v=BIMI1; l=https://fizjoterapia.uk/bimi.svg SPF Sender Policy Framework (SPF) is an email authentication method which ensures the sending mail server is authorized to originate mail from the email sender’s domain. It is absolutely necessary to have SPF entry in DNS zone - otherwise your email will end-up in SPAM folder or even will be discarded....

July 23, 2023 · 5 min · Bart Prokop

OCI Setup

Oracle provides generous “free-tier” for its CLoud. This article describes the basic setup to maximize OCI “always free” tier. Prerequisites Run Oracle Cloud Shell and generate SSH keypair, that you will use with OCI instances. Here come surprise… My preferred key type is ed25519, it is the most recommended public-key algorithm available today! But if I try to create it, the following error is presented: ED25519 keys are not allowed in FIPS mode Apparently, Oracle is part of FIPS / NIST security theater (or NSA collaborator) and follows non-sense compliance rules by letter and spirit, ignoring this [https://csrc....

December 27, 2022 · 6 min · Bart Prokop

Media Player for Christmas

This Christmas decided to gift to my significant other a Game Of Thrones Blu Ray set (4k, UHD - 33 discs total). This post cover all what I needed to do to get it watched on living room’s TV (which is LG OLED). The first obvious obstacle has ocurred - I do not have the Blu Ray Player (not even mentioning UHD Blue Ray). It is 2022/23 and physical media are slightly a thing of past....

December 25, 2022 · 1 min · Bart Prokop

SSHd Server on Android

Description how I transfer files from my Android phone to Linux server. This will use FUSE to mount Android storage as linux directory. Example solution is to backup all photos from Android phone. Android setup Please install https://play.google.com/store/apps/details?id=org.galexander.sshd from Android Play store. This is port of https://en.wikipedia.org/wiki/Dropbear_(software) to Android. Linux Setup Use ssh from terminal to log-in to your Android phone. # username does not matter, use password shown in Android console for the very first login ssh bart@192....

December 4, 2022 · 2 min · Bart Prokop

Hurricane Electric Filtered Tunnel

➜ ~ sudo nmap -p - -6 paris.prokop.dev Starting Nmap 7.93 ( https://nmap.org ) at 2022-11-21 23:04 GMT Nmap scan report for paris.prokop.dev (2001:41d0:e:514::1) Host is up (0.062s latency). Other addresses for paris.prokop.dev (not scanned): 5.196.72.20 Not shown: 65518 closed tcp ports (reset) PORT STATE SERVICE 22/tcp open ssh 25/tcp filtered smtp 5355/tcp filtered llmnr 6660/tcp filtered unknown 6661/tcp filtered unknown 6662/tcp filtered radmind 6663/tcp filtered unknown 6664/tcp filtered unknown 6665/tcp filtered irc 6666/tcp filtered irc 6667/tcp filtered irc 6668/tcp filtered irc 6669/tcp filtered irc 6670/tcp filtered irc 6697/tcp filtered ircs-u 7000/tcp filtered afs3-fileserver 9999/tcp filtered abyss Nmap done: 1 IP address (1 host up) scanned in 119....

November 21, 2022 · 1 min · Bart Prokop