Commands by christian773 (6)

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Detect illegal access to kernel space, potentially useful for Meltdown detection
Based on capsule8 agent examples, not rigorously tested

Puts every word from a file into a new line
Simply translates whitespace to newlines. Could be enhanced to compress out extra newlines, but that might be better handled in the next tool down the pipe, with eg uniq(1).

Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

Randomize lines (opposite of | sort)
Randomizes a file. The opposite of sort is sort -R!

reset an hanging terminal session
when your terminal session seems unrensponsive (this normally happen after outputting some binary data directly on your standard output) it may me saned by hitting: CTRL+J tput sgr0 CTRL+J Note: don't press the Enter key, just ctrl+j

Get AWS temporary credentials ready to export based on a MFA virtual appliance
You might want to secure your AWS operations requiring to use a MFA token. But then to use API or tools, you need to pass credentials generated with a MFA token. This commands asks you for the MFA code and retrieves these credentials using AWS Cli. To print the exports, you can use: `awk '{ print "export AWS_ACCESS_KEY_ID=\"" $1 "\"\n" "export AWS_SECRET_ACCESS_KEY=\"" $2 "\"\n" "export AWS_SESSION_TOKEN=\"" $3 "\"" }'` You must adapt the command line to include: * $MFA_IDis ARN of the virtual MFA or serial number of the physical one * TTL for the credentials

Clean way of re-running bash startup scripts.
This replaces the current bash session with a new bash session, run as an interactive non-login shell... useful if you have changed /etc/bash.bashrc, or ~/.bashrc If you have changed a startup script for login shells, use $ exec bash -l Suitable for re-running /etc/profile, ~/.bash_login and ~/.profile. edit: chinmaya points out that $ env - HOME=$HOME TERM=$TERM bash -s "exec bash -l" will clear any shell variables which have been set... since this verges on unwieldy, might want to use $ alias bash_restart='env - HOME=$HOME TERM=$TERM bash -s "exec bash -l"'

list processes with established tcp connections (without netstat)
Uses lsof to list open network connections (file descriptors), grepping for only those in an established state

Show what PID is listening on port 80 on Linux

Set laptop display brightness
Run as root. Path may vary depending on laptop model and video card (this was tested on an Acer laptop with ATI HD3200 video). $ cat /proc/acpi/video/VGA/LCD/brightness to discover the possible values for your display.

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