Commands by dasmna (2)

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Port Knocking!
Knock on ports to open a port to a service (ssh for example) and knock again to close the port. You have to install knockd. See example config file below. [options] logfile = /var/log/knockd.log [openSSH] sequence = 3000,4000,5000 seq_timeout = 5 command = /sbin/iptables -A INPUT -i eth0 -s %IP% -p tcp --dport 22 -j ACCEPT tcpflags = syn [closeSSH] sequence = 5000,4000,3000 seq_timeout = 5 command = /sbin/iptables -D INPUT -i eth0 -s %IP% -p tcp --dport 22 -j ACCEPT tcpflags = syn

Convert CSV to JSON
Replace 'csv_file.csv' with your filename.

sort list of email addresses by domain.tld
email random list can be created here: https://www.randomlists.com/email-addresses

get all Amazon cloud (amazonws etc) ipv6 subnets

Delete all files in a folder that don't match a certain file extension
Deletes all files in a folder that are NOT *.foo, *.bar or *.baz files. Edit the pattern inside the brackets as you like.

Trim linebreaks

quick copy
Utilizes shell expansion of {} to give the original filename and a new filename as arguments to `cp`. Can easily be extended to make multiple copies.

Kill processes that have been running for more than a week

List out classes in of all htmls in directory
Lists out all classes used in all *.html files in the currect directory. usefull for checking if you have left out any style definitions, or accidentally given a different name than you intended. ( I have an ugly habit of accidentally substituting camelCase instead of using under_scores: i would name soemthing counterBox instead of counter_box) WARNING: assumes you give classnames in between double quotes, and that you apply only one class per element.

Randomize lines in a file
shuf is in the coreutils package


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