launch agent executing with root account in Yosemite - macos

I'm trying to execute my test daemon by launchd with logon user privilege.
I saved my plist file at /Library/LaunchAgents/myplist and it was executed well with logon user account at Mavericks.
My command was like this.
$launchctl load /Library/LaunchAgents/myplist
But it was executed as root account when I tried it at Yosemite.
As I know, it should be executed as logon user account, but it wasn't at Yosemite. I also moved myplist file to ~/Library/LauchAgents/myplist, but the result was same.
What happend to Launchd at Yosemite and how can I execute launchd with logon user account?


The user can be specified in the daemon's plist with the UserName key. For example: -
<key>UserName</key>
<string>_daemonUser</string>
Where _daemonUser is the name of the user the daemon should run as, assuming that a user with that name exists.
If you want to use the name of the current logged-in user, you'll have to specify that when calling launchctl load. In a bash script, run with sudo, you can do something like this: -
SESSION_USER="$USER"
echo Starting MyDaemon as user $SESSION_USER
su $SESSION_USER -c 'launchctl load /Library/LaunchAgents/myplist.plist'
You may need to consider other users too, if user switching is applicable and they're already logged-in. This is more complicated, but there's a solution here.

Related

Check if current user is different than the default user in bash script

I want to check if I am using elevated user rights, like running su another_user and seeing my original user name / id.
All I found when researching that topic is either hardcode my own username somewhere, or examples for root user only (id=0).
I think zsh has a variable for that: $DEFAULT_USER, but it's not working in bash.

How to initiate my exe file from administrative command prompt

I have logged in with one user in my system. Like, userA. Now, I have opened command prompt window with administrator privileges. In same Administrator command prompt window need to run my EXE file for userA without the password.
I have tried "RunAs" command but it will ask for Password.
Is there any other alternative, where I can solve my problem.

I have logged in with one user in my system. Like, userA.
Ok...
In same Administrator command prompt window need to run my EXE file for userA without the password.
So you are already logged in as userA why would you need to enter the passsword again?
If you need to run something as as a different user you can create a batch file and set up a scheduled task to run it with their credentials, but don't actually give it a schedule. When you are then logged in as a differnt user you can call the scheduled task and it will run as the user it is associated with.

shell script executes as root when it should execute as current logged in user

I was logged in via SSH as the user who was currently logged in.
I enter the remote computer using my admin account.
ssh admin_a#ipaddress
Then proceeded with:
su username_b (current login user)
The result left me in bash-prompt (which I don't understand) as the current user logged in ( tested this by using whoami ).
Q1: When I switch over to the user who is logged in, why does it put me into bash-prompt (i.e. ~bash$ ) - why not ~ username_of_current_user$ ?
After I created the bash script and placed it into the current user's directory - the script is called from launch agents, although it doesn't work.
The error logs showed that one of the variable's output is wrong: whoami = root, when it should = current_user_logged_in.
Q2: Why is the script being called from root?

su - invokes a login shell after switching the user. A login shell resets most environment variables, providing a clean base.
su just switches the user, providing a normal shell with an environment nearly the same as with the old user.
The most obvious example of this is that ~ is root's home directory if you use su -, but your own home directory if you use su.
Depending on your system, it may also mean differences in prompt, PATH, or history file.
For more details:
https://unix.stackexchange.com/questions/7013/why-do-we-use-su-and-not-just-su

Usernames in /etc/passwd

I'm new to linux operating system and I've explored today the /etc/passwd file and to my surprise I found that it contains many other user names like proxy,daemon..etc.What are all these users?Can I login using these users?
Here the cat command i performed on /etc/passwd.
root:x:0:0:root:/root:/bin/bash
daemon:x:1:1:daemon:/usr/sbin:/usr/sbin/nologin
bin:x:2:2:bin:/bin:/usr/sbin/nologin
sys:x:3:3:sys:/dev:/usr/sbin/nologin
sync:x:4:65534:sync:/bin:/bin/sync
games:x:5:60:games:/usr/games:/usr/sbin/nologin
man:x:6:12:man:/var/cache/man:/usr/sbin/nologin
lp:x:7:7:lp:/var/spool/lpd:/usr/sbin/nologin
mail:x:8:8:mail:/var/mail:/usr/sbin/nologin
news:x:9:9:news:/var/spool/news:/usr/sbin/nologin
uucp:x:10:10:uucp:/var/spool/uucp:/usr/sbin/nologin
proxy:x:13:13:proxy:/bin:/usr/sbin/nologin
www-data:x:33:33:www-data:/var/www:/usr/sbin/nologin
backup:x:34:34:backup:/var/backups:/usr/sbin/nologin
list:x:38:38:Mailing List Manager:/var/list:/usr/sbin/nologin
irc:x:39:39:ircd:/var/run/ircd:/usr/sbin/nologin
gnats:x:41:41:Gnats Bug-Reporting System (admin):/var/lib/gnats:/usr/sbin/nologin
nobody:x:65534:65534:nobody:/nonexistent:/usr/sbin/nologin
libuuid:x:100:101::/var/lib/libuuid:
syslog:x:101:104::/home/syslog:/bin/false
messagebus:x:102:106::/var/run/dbus:/bin/false
usbmux:x:103:46:usbmux daemon,,,:/home/usbmux:/bin/false
dnsmasq:x:104:65534:dnsmasq,,,:/var/lib/misc:/bin/false
avahi-autoipd:x:105:113:Avahi autoip daemon,,,:/var/lib/avahi-autoipd:/bin/false
kernoops:x:106:65534:Kernel Oops Tracking Daemon,,,:/:/bin/false
rtkit:x:107:114:RealtimeKit,,,:/proc:/bin/false
saned:x:108:115::/home/saned:/bin/false
whoopsie:x:109:116::/nonexistent:/bin/false
speech-dispatcher:x:110:29:Speech Dispatcher,,,:/var/run/speech-dispatcher:/bin/sh
avahi:x:111:117:Avahi mDNS daemon,,,:/var/run/avahi-daemon:/bin/false
lightdm:x:112:118:Light Display Manager:/var/lib/lightdm:/bin/false
colord:x:113:121:colord colour management
daemon,,,:/var/lib/colord:/bin/false
hplip:x:114:7:HPLIP system user,,,:/var/run/hplip:/bin/false
pulse:x:115:122:PulseAudio daemon,,,:/var/run/pulse:/bin/false
brucewilson:x:1000:1000:brucewilson,,,:/home/brucewilson:/bin/bash
mysql:x:116:125:MySQL Server,,,:/nonexistent:/bin/false
bharghav:x:1001:1001:bharghav,,,:/home/bharghav:/bin/bash
sshd:x:117:65534::/var/run/sshd:/usr/sbin/nologin
statd:x:118:65534::/var/lib/nfs:/bin/false
snmp:x:119:126::/var/lib/snmp:/bin/false
guest-MSvo95:x:120:127:Guest,,,:/tmp/guest-MSvo95:/bin/bash
Can anyone please explain what are these?

Most of those users are required by the OS processes to work. You can't login as one of those users because:
a. They don't have a shell as regular users does. For example, brucewilson has /bin/bash as shell, but pulse (Audio Controller ) has /bin/false.
b. There are not passwords for those users, so when the system asks for a password, no matter what you type you will never get in. You can check who has a password in /etc/shadow.

Actually, you can login as any user listed in /etc/passwd as of your choice.
for example, if you want to login as proxy, type the following command:
sudo -u proxy /bin/bash
It will asks password to authenticate the access, you can give your password only if your user account is added in sudoers list.
You can use the same command to login as any user in the /etc/passwd file.
For example, again if you want to log in as daemon, type the following command:
sudo -u daemon /bin/bash
and so on...
Hope this will help you.

how does permission works to run sbin command on mac..?

i'm using mac os x and i was trying to run shutdown command but it says
i'm not a superuser.
However, i could run ifconfig without being super user.
Both command are in /sbin.
And my PATH environment variable include /sbin ( is that why i can run ifconfig..?).
From what i have found, it says that
/sbin
for scripts with superuser (root) privileges required.
But i'm not quite sure about this explanation..
I'd appreciate all your help..

it means that you must be superuser (the owner of the machine) to run those commands, for example:
sudo shutdown
it will ask for a password, you must type the main user's password (the typing will not print out the password's chars) and press enter so you can confirm you are the super user.
sudo allows a permitted user to execute a command as the superuser or another user, as specified in the sudoers file. more: http://ss64.com/bash/sudo.html

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