I want to install a the pub key for user test using the command below.
I know the root password and the user test does not exist.
cat test.pub | ssh root#127.0.0.1 "useradd -m test || su - test -c 'umask 077; mkdir /home/test/.ssh; cat >> /home/test/.ssh/authorized_keys'"
But the command does not work.
Error: Creating mailbox file: File exists
The problem is useradd -m test. I delete user test by userdel test && rm -rf /home/test. It should be userdel -r test.
The command below works:
cat test.pub | ssh root#127.0.0.1 "useradd -m test && su - test -c 'umask 077; mkdir /home/test/.ssh; cat >> /home/test/.ssh/authorized_keys'"
Related
I would like to check if the user has sudo privileges. This is an approximate example of what I am trying to do. I am trying to get this to work across the following os: centos, ubuntu, arch.
if userIsSudo; then
chsh -s $(which zsh)
fi
Try with this:
$ sudo -v &> /dev/null && echo "Sudoer" || echo "Not sudoer"
Also, IDK how secure will be searching for his membership in the sudo group, i.e:
$ groups "$(id -un)" \
| grep -q ' sudo ' \
&& echo In sudo group \
|| echo Not in sudo group
Or:
$ getent group sudo \
| grep -qE "(:|,)$(id -un)(,|$)" \
&& echo in sudo group \
|| echo not in sudo group
sudo -l will display the commands that the user can run with sudo privileges. If there are no commands that can be run, sudo -l will return an error code and so you could try:
sudo -l && chsh -s $(which zsh)
Usually when you run an script you want to know if end it well or you got an error or what kind of error you got if there was any.
This is a more elaborated snippet, sudoer-script.sh:
## Define error code
E_NOTROOT=87 # Non-root exit error.
## check if is sudoer
if ! $(sudo -l &> /dev/null); then
echo 'Error: root privileges are needed to run this script'
exit $E_NOTROOT
fi
## do something else you
## means it was successfully executed
exit 0
Now you can reuse your script, pipe it or concatenate with other commands
sudoer-script.sh && ls
## in a script
if $(sudoer-script.sh); then
echo 'success'
fi
## capture error
stderr=$(./sudoer-script.sh 2>&1 >/dev/null)
echo $stderr
As a function:
is_sudoer() {
## Define error code
E_NOTROOT=87 # Non-root exit error.
## check if is sudoer
if ! $(sudo -l &> /dev/null); then
echo 'Error: root privileges are needed to run this script'
return $E_NOTROOT
fi
return 0
}
if is_sudoer; then
echo "Sudoer"
else
echo "Not sudoer"
fi
I tried limiting ls command to a specific user. It works, but when I execute /bin/ls, it executes successfully again, how to restrict here.
useradd -m $username -s /bin/rbash
echo "$username:$password" | chpasswd
mkdir /home/$username/bin
chmod 755 /home/$username/bin
echo "PATH=$HOME/bin" >> /home/$username/.bashrc
echo "export PATH" >> /home/$username/.bashrc
ln -s /bin/ls /home/$username/bin/
I wrote a shell script like this
#!/bin/bash
sudo mkdir /var/www/html/test
sudo cp ./index.html /var/www/html/test/index.html
echo "Hi" > /var/www/html/test/index.html
if I runt this with sudo it works well.
$ sudo ./script.sh
but I don't want to run with sudo. because echo doesn't need root privilege. In other hand if I run this without sudo like this:
$ ./script.sh
for the first command (mkdir) it asks me for root password and second command doesn't run and give me a permission denied error.
How can I handle this situation?
Based on your setup, e.g. in ubuntu if I run sudo 2 times, the second time I don't have to give the password. So it is possible that the second sudo DID run, without asking for password again.
You can clarify, try this:
sudo echo a
sudo echo b
It is most likely, as Kip K commented, the error originates from the echo "Hi"... since the normal user has no permission to write /var/www/html/test/index.html .
Kinda overkill, but you can give constant feedback like this:
sudo bash -c 'echo mkdir; mkdir /var/www/html/test'
sudo bash -c 'echo cp; cp ./index.html /var/www/html/test/index.html'
Try chown for directory test:
#!/bin/bash
sudo bash -c 'mkdir /var/www/html/test && chown -R USER /var/www/html/test'
cp ./index.html /var/www/html/test/index.html
echo "Hi" > /var/www/html/test/index.html
or ... chmod o+w /var/www/html/test
I am trying to execute the following command but the output is not coming as required.
var=$(echo "<password>"|sudo -S su -l <user> -c "<command>")
Please help if anyone can?
Expected Result:
var=$(echo ""|sudo -S su -l -c "pwd")
echo $var /home/bhushan
$:
Actual Result:
echo $var
$:
You can use backticks
var=`sudo -S su -l -c ""`
or the $(command) syntax
var=$(sudo -S su -l -c "")
(keep in mind though that sudo -S su -l -c "" doesn't output anything so $var will be empty)
You can workaround it by storing the output of the command into a file, then change its permission so that all users will see it and in a following command load it from the file:
sudo -S "<command> > /tmp/sudocmd.out && chmod 644 /tmp/sudocmd.out"
var=$(cat /tmp/sudocmd.out)
User x run a script. Now I want to change the user in the script to User y.
#!/bin/sh
whoami
echo password | su y
whoami
But I get this:
x
su: must be run from a terminal
x
Thanks for your help.
This is working for me inside a bash script:
whoami;
sudo su $user << BASH
whoami;
BASH
Su cannot be ran in a Bash script. You can use sudo -u <user> <command> && however.
you can do:
su - $USER -l -m -c $CMD
-l provide an environment similar to the login env
-m preserves the current environment
-c runs the command
e.g. I use this to run nohup commands also
su - $USER -l -m -c "nohup $RUN_CMD > "$LOG" 2>&1 >> /dev/null&"