Archive for the ‘bash’ Category
Posted by jpluimers on 2025/03/06
Two sites that can help you out getting weather info on the console:
wttr.in
wttr.in is developed by [Wayback/Archive] Igor Chubin (@igor_chubin) / X and looks at the request header to figure out what kind of output it sends.
It supports various output formats, so on my TODO list is to see how they do their mapping: always an opportunity to learn (it’s based on Python and Go so I am curious what libraries they use as well).
From the documentation:
wttr.in currently supports five output formats:
- ANSI for the terminal;
- Plain-text for the terminal and scripts;
- HTML for the browser;
- PNG for the graphical viewers;
- JSON for scripts and APIs;
- Prometheus metrics for scripts and APIs.
The ANSI and HTML formats are selected based on the User-Agent string.
There are more parameters in the documentation on the main page of the repository and through this command:
curl wttr.in/:help
The idea is derived from [Wayback/Archive] GitHub – schachmat/wego: weather app for the terminal.
Oh: Igor has more repositories at [Wayback/Archive] chubin (Igor Chubin) · GitHub (including [Wayback/Archive] GitHub – chubin/cheat.sh: the only cheat sheet you need which is hosted at [Wayback/Archive] cheat.sh; I thought I had blogged about that before, but found it only in a draft note mentioning that I got it via [WaybackSave/Archive] Nicolas Krassas on X: “The only cheat sheet you need cheat.sh“)
7timer
A 7 timer JSON usage example is at [Wayback/Archive] Get Weather from 7Timer! · GitHub
It has documentation at
Output formats can be chosen from HTML, PNG, XML and JSON.
Via
[Wayback/Archive] Hacker Public Radio – hpr4266 :: What’s the weather?
Lee writes a script to check what the weather is like ~ The Technology Community Podcast
HPR is a great podcast series!
--jeroen
Posted in *nix, *nix-tools, ash/dash, bash, bash, Development, Go (golang), JavaScript/ECMAScript, JSON, Power User, Python, Scripting, Software Development, Web Development, XML/XSD | Leave a Comment »
Posted by jpluimers on 2024/02/22
Cool: [Wayback] ShellCheck – shell script analysis tool
ShellCheck finds bugs in your shell scripts
It needs a shebang at the start of a script (like #!/usr/bin/env bash) to recognise the kind of shell, then does amazing analysis.
It is open source at [Wayback/Archive.is] koalaman/shellcheck: ShellCheck, a static analysis tool for shell scripts with excellent documentation including explaining screenshots like
It’s not just available on-line or on the command-line, but also integrates with many code editors (like [Wayback/Archive.is] ShellCheck – Visual Studio Marketplace: Integrates ShellCheck into VS Code, a linter for Shell scripts.) and CI/CD pipelines.
Via: [Wayback] bash – error conditional binary operator expected in compound branch – Unix & Linux Stack Exchange (thanks [Wayback] Cyrus!)
–jeroen
Posted in *nix, *nix-tools, ash/dash, ash/dash development, bash, bash, Development, Power User, Scripting, Software Development | Leave a Comment »
Posted by jpluimers on 2023/10/17
Posted in *nix, *nix-tools, bash, bash, Development, JavaScript/ECMAScript, jo, jq, JSON, man/manual pages, mankier, Power User, Python, Scripting, Software Development | Leave a Comment »
Posted by jpluimers on 2023/09/14
For my link archive so I can better automate archiving Tweet threads using bookmarklets written in JavaScript:
The base will likely be this:
javascript:void(open(`https://archive.is/?run=1&url=${encodeURIComponent(document.location)}`))
which for now I have modified into this:
javascript:void(open(`https://threadreaderapp.com/search?q=${document.location}`))
It works perfectly fine without URL encoding and demonstrates the JavaScript backtick feature for template literals for which you can find documentation at [WayBack/Archive] Template literals – JavaScript | MDN.
Read the rest of this entry »
Posted in *nix, *nix-tools, bash, bash, Bookmarklet, Communications Development, cURL, Development, HTTP, https, Internet protocol suite, Power User, Scripting, Security, Software Development, TCP, Web Browsers | Leave a Comment »
Posted by jpluimers on 2023/08/17
A while ago I wrote about Figuring out the open network connections for processes ran by python, which explained the TL;DR:
pidof python | tr " " "\n" | xargs -r -n 1 lsof -i -a -e /run/user/1001/gvfs -p
Now I needed thread information as well, so below two examples using ps and pstree. I won’t explain the pidof and xargs stuff here as that was already covered in the above blog-post and I found out that ps already has a built-in way to filter on process name.
The ps solution uses the H, -L or -T argument to show the threads:
Read the rest of this entry »
Posted in *nix, *nix-tools, bash, Development, lsof, Power User, ps, Scripting, Software Development | Leave a Comment »
Posted by jpluimers on 2023/07/26
TL;DR is at the bottom (;
5 days ago this exploit development got published: [Wayback/Archive] snowcra5h/CVE-2023-38408: CVE-2023-38408 Remote Code Execution in OpenSSH’s forwarded ssh-agent.
It is about [Wayback/Archive] NVD – CVE-2023-38408 which there at NIST isn’t rated (yet?), neither at [Wayback/Archive] CVE-2023-38408 : The PKCS#11 feature in ssh-agent in OpenSSH before 9.3p2 has an insufficiently trustworthy search path, leading to remot.
However at [Wayback/Archive] CVE-2023-38408- Red Hat Customer Portal it scores 7.3 and [Wayback/Archive] CVE-2023-38408 | SUSE it did get a rating of 7.5, so since I mainly use OpenSuSE I wondered what to do as the CVE is formulated densely at [Wayback/Archive] www.qualys.com/2023/07/19/cve-2023-38408/rce-openssh-forwarded-ssh-agent.txt: it mentions Alice, but no Bob or Mallory (see Alice and Bob – Wikipedia).
Luckily, others readly already did the fine reading and emphasised the important bits, especially at [Wayback/Archive] RCE Vulnerability in OpenSSH’s SSH-Agent Forwarding: CVE-2023-38408 (note that instead of Alex, they actually mean Alice)
“A system administrator (Alice) runs SSH-agent on her local workstation, connects to a remote server with ssh, and enables SSH-agent forwarding with the -A or ForwardAgent option, thus making her SSH-agent (which is running on her local workstation) reachable from the remote server.”
According to researchers from Qualys, a remote attacker who has control of the host, which Alex has connected to, can load (dlopen()) and immediately unload (dlclose()) any shared library in /usr/lib* on Alice’s workstation (via her forwarded SSH-agent if it is compiled with ENABLE_PKCS11, which is the default).
The vulnerability lies in how SSH-agent handles forwarded shared libraries. When SSH-agent is compiled with ENABLE_PKCS11 (the default configuration), it forwards shared libraries from the user’s local workstation to the remote server. These libraries are loaded (dlopen()) and immediately unloaded (dlclose()) on the user’s workstation. The problem arises because certain shared libraries have side effects when loaded and unloaded, which can be exploited by an attacker who gains access to the remote server where SSH-agent is forwarded to.
Mitigations for the SSH-Agent Forwarding RCE Vulnerability
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Posted in *nix, *nix-tools, bash, bash, Communications Development, Development, Internet protocol suite, OpenSSH, Power User, PowerShell, Scripting, Security, Software Development, SSH | Leave a Comment »
Posted by jpluimers on 2023/07/11
TL;DR:
pidof python | tr " " "\n" | xargs -r -n 1 lsof -i -a -e /run/user/1001/gvfs -p
Breakdown:
Via:
–jeroen
Posted in *nix, *nix-tools, bash, bash, Development, lsof, Power User, Scripting, Software Development, xargs | Leave a Comment »
Posted by jpluimers on 2023/05/17
A while ago, I needed the file information of wsl.exe on one of my Windows systems.
On Linux, I would do something like file `which bash` where file will give the file details and which gets you the full path to bash.
The file equivalent on Windows for me is [Wayback/Archive] Sigcheck – Windows Sysinternals | Microsoft Docs, which is part of [Wayback/Archive] File and Disk Utilities – Windows Sysinternals | Microsoft Docs.
The which equivalent on Windows for me is [Wayback/Archive] where | Microsoft Docs.
Read the rest of this entry »
Posted in bash, Batch-Files, CommandLine, Development, PowerShell, PowerShell, Scripting, Software Development | 1 Comment »
Posted by jpluimers on 2023/04/18
Cool one-liner program via [Archive] Jilles🏳️🌈 (@jilles_com) / Twitter:
for s in 0123456789ABCDEF 172.16.0.254 Passwd:admin;do echo -en "Big Endian: $s\nMiddle Endian: ";echo -n $s|xxd -e -g 4 | xxd -r;echo -en "\nLittle Endian: ";echo -n $s|xxd -e -g 2 | xxd -r;echo -en "\nReversed : ";echo -n $s|xxd -p -c1 | tac | xxd -p -r;echo -e "\n";done
Note that the hex are bytes, not nibbles, so the endianness is OK:
Big Endian: 0123456789ABCDEF
Middle Endian: 32107654BA98FEDC
Little Endian: 1032547698BADCFE
Reversed : FEDCBA9876543210
Big Endian: 172.16.0.254
Middle Endian: .2710.61452.
Little Endian: 71.2610.2.45
Reversed : 452.0.61.271
Big Endian: Passwd:admin
Middle Endian: ssaPa:dwnimd
Little Endian: aPssdwa:mdni
Reversed : nimda:dwssaP
That nibble/byte thing confused me at first (as I associate hexadecimal output with hex dumps, where each hexadecimal character represents a nibble)) so here are some interesting messages from the thread that Jilles_com started:
Some related man pages:
–jeroen
Posted in *nix, *nix-tools, bash, Development, Power User, Scripting, Software Development, xxd | Leave a Comment »
Posted by jpluimers on 2023/03/16
PolyShell is a script that’s simultaneously valid in Bash, Windows Batch, and PowerShell (i.e. a polyglot).
[Wayback/Archive] llamasoft/polyshell: A Bash/Batch/PowerShell polyglot!
Need to check this out, as often I have scripts that have to go from one language to the other or vice versa.
Maybe it enables one language to bootstrap functionality in the other?
The quest
The above polyglot started with a quest to see if I can could include some PowerShell statements in a batch file with two goals:
- if the batch file started from the PowerShell command prompt, then execute the PowerShell code
- if the batch file started from the
cmd.exe command prompt, then have it start PowerShell with the same command-line arguments
The reasoning is simple:
- PowerShell scripts will start from the PATH only when PowerShell is already running
- Batch files start from the path when either
cmd.exe or PowerShell are running
Lots of users still live in the cmd.exe world, but PowerShell scripts are way more powerful, and since PowerShell is integrated in Windows since version 7, so having a batch file bootstrap PowerShell still makes sense.
Since my guess was about quoting parameters the right way, my initial search for the link below was [Wayback/Archive] powershell execute statement from batch file quoting – Google Search.
I have dug not yet into this, so there are still…
Many links to read
These should give me a good idea how to implement a polyglot batch file/PowerShell script.
–jeroen
Posted in *nix, *nix-tools, bash, bash, Batch-Files, Development, JavaScript/ECMAScript, Perl, Polyglot, Power User, PowerShell, Scripting, Software Development | Leave a Comment »
The Wiert Corner - irregular stream of stuff 