See "Parameter Expansion" in the bash manpage. They refer to this as "Use Alternate Value", but we're including the var in the at alternative.

The read command reads input and puts it into a variable. With -i you set an initial value. In this case I used a known environment variable.

In this case the current user has proxy variable set which allows access to the rpm on the internet but needs root privs to install it.

Running sudo -E preserves the current user proxy var and allows the rpm install to be executed with sudo.

If this matches any files on your web server expect to find allot of malware spread throughout your server folders. Seems to target wordpress sites. Be sure to check your themes/theme-name/header.php files manually for various redirect scripting usually in the line right above the close head tag.

Good luck!

Someone quoted Pooh in an init script. Let's see it!

(Probably only works on Debian & friends)

You can search for CVEs at https://security-tracker.debian.org/tracker/ or use --report to get full links. This can be added to cron, but unless you're going to do manual patches, you'd just be torturing yourself.

This command will display the file, but you can change 'cat' to anything else

(type 'n' when prompted to cancel the command or anything else to proceed).

.

Some hints for newbies:

type

to make 'bar' function annihilated.

For permanent usage you can put this (bar) function in your .bashrc (for bash) or in .profile (for sh).

With:

you can get all new inserted functions in .bashrc (so the function 'bar'

or whatever name you choose) immediately available.

tcpdump into file with date format for wireshark

capture trafic for wireshark from spesific eth interface

This command validates if exist any character different in 0-255 and dot.

If any characters different is typed the error menssage is showing.

Print out your age in days in binary.

Today's my binary birthday, I'm 2^14 days old :-)

.

This command does bash arithmatic $(( )) on two dates:

Today: $(date +%s)

Date of birth: $(date +%s -d YYYY-MM-DD)

The dates are expressed as the number of seconds since the Unix epoch (Jan 1970),

so we devide the difference by 86400 (seconds per day).

.

Finally we pipe "obase=2; DAYS-OLD" into bc to convert to binary.

(obase == output base)

Often you run a command, but afterwards you're not quite sure what it did.

By adding this prefix/suffix around [COMMAND], you can list any files that were modified.

.

Take a nanosecond timestamp: YYYY-MM-DD HH:MM:SS.NNNNNNNNN

.

Find any files that have been modified since that timestamp:

.

This command currently only searches below the current directory.

If you want to look elsewhere change the find parameter, e.g.

This lists all files modified after calling some command using a temporal anchor.

In pre-systemd systems, something like: "# grep sshd /var/log/messages" would display log events in /var/log/messages containing "sshd".

# journalctl -u sshd --no-pager

The above command displays similar results for systemd systems.

(Note that this needs to be run with root permissions to access the log data.)

View files in ZIP archive

unzip -l files.zip

Extract only a specific file from a zipped archive to a given directory

unzip -j "myarchive.zip" "in/archive/file.txt" -d "/path/to/unzip/to"

unzip /surce/file.zip -d /dest/

./script.sh

# suspend process

{ctrl-Z}

# background process

bg

# list all backgrounded jobs

jobs

# bring it back to foreground

fg

A wrapper around ssh to automatically provide logging and session handling.

This function runs ssh, which runs screen, which runs script.

.

The logs and the screen session are stored on the server.

This means you can leave a session running and re-attach to it later, or from another machine.

.

.

Requirements:

* Log sessions on a remote server

* Transparent - nothing extra to type

* No installation - nothing to copy to the server beforehand

.

Features:

* Function wrapper delegating to ssh

- so nothing to remember

- uses .ssh/config as expected

- passes your command line option to ssh

* Self-contained: no scripts to install on the server

* Uses screen(1), so is:

- detachable

- re-attachable

- shareable

* Records session using script(1)

* Configurable log file location, which may contain variables or whitespace

L="$HOME" # local variable

L="\$HOME" # server variable

L="some space"

.

Limitations:

* Log dir/file may not contain '~' (which would require eval on the server)

.

.

The sessions are named by the local user connecting to the server.

Therefore if you detach and re-run the same command you will reconnect to your original session.

If you want to connect/share another's session simply run:

.

The command above is stripped down to an absolute minimum.

A fully expanded and annotated version is available as a Gist (git pastebin):

https://gist.github.com/flatcap/3c42326abeb1197ee714

.

If you want to add timing info to script, change the command to:

Source: http://superuser.com/a/624574

Downloads Bluetack's level 1 IP blocklist in .p2p format, suitable for various Bittorrent clients.