Jan Kończak

This page is read only. You can view the source, but not change it. Ask your administrator if you think this is wrong.
<html><code></html>
|~~#~~|whoami|
|~~#~~|groups|
|:::|id|
|~~#~~|id|
|:::|getent passwd //your_username// \\ # uid is the third, and gid the fourth field|
|~~#~~|w -n|
|~~#~~|last -wn 10 \\ # displays 10 last logons|
|~~#~~|last root|
|~~#~~|last --present '2023-03-03 13:30'|
|~~#~~|write //username// \\ //message// \\ <color #808080>//Ctrl+d//</color>|
|~~#~~|su \\ exit \\ # lub //Ctrl+d// \\ su user//5// \\ exit|
|~~#~~|ls -ld ~ ~/.ssh ~/.bash_history /etc/passwd /etc/shadow /tmp /usr/bin/passwd /usr/bin/write|
|:::|stat ~ ~/.ssh ~/.bash_history /etc/passwd /etc/shadow /tmp /usr/bin/passwd /usr/bin/write|
|:::|# the exercise shows examples of real-world permission usage; ponder why such permissions are set|
|~~#~~|ls -l /var/run /dev/sda /dev/nvme0n1 /dev/null /run/initctl /run/rpcbind.sock|
|:::|stat /var/run /dev/sda /dev/nvme0n1 /dev/null /run/initctl /run/rpcbind.sock|
|:::|# the exercise shows the possible file types (apart from an ordinary file and a directory)|
|~~#~~|fortune > file1 \\ chmod go-r file1 \\ su user//2// \\ cat file1 \\ exit \\ su user//3// \\ cat file1 \\ exit |
|:::|fortune > file1 \\ chmod go-r file1 \\ su user//2// -c "cat file1" \\ su user//3// -c "cat file1"|
|~~#~~|fortune > file2 \\ chmod 640 file2 \\ # verify as above|
|~~#~~|fortune > file3 \\ chmod o-r file3 \\ # alternatively: chmod u=rw,g=r,o= file3|
|~~#~~|chgrp left file3|
|~~#~~|fortune > file4 \\ chmod 604 file4 \\ # verify as in 31|
|~~#~~|mkdir dir1 \\ fortune > dir1/a \\ chmod -x dir1 \\ ls dir1 \\ cd dir1 \\ cat dir1/a |
|~~#~~|chmod u=rwx,go=rx dir1 \\ su user//2// \\ cat dir1/a \\ ls dir1 \\ exit \\ chmod go-r dir1 \\ # repeat cat  and ls as user//2// |
|~~#~~|mkdir dir2 \\ cd dir2 \\ touch a b \\ chmod go-r b \\ su user//2// \\ rm a \\ rm b \\ exit|
|~~#~~|cd ~/dir2 \\ su user//2// \\ mkdir d1 d2 \\ touch d2/f \\ exit \\ rm -r d1 \\ rm -r d2|
|~~#~~|cd ~/dir2 \\ mv d2 foo \\ mv foo ~ \\ cd .. \\ mkdir dir3 \\ mv dir2 dir3 |
|~~#~~|mkdir dir4 \\ fortune > file5 \\ fortune > dir4/f \\ chmod -R 0 dir4 file5 \\ su \\ cat file5 \\ cd dir4 \\ cat f \\ exit|
|~~#~~|su \\ chown user//2// file1 \\ chown :www-data file2  \\ exit|
|~~#~~|stat /var/log/wtmp \\ # take notice of the last access date which might precede last modify date|
|~~#~~|touch ~|
|~~#~~|touch -d '13:30 PDT Saturday month ago' //file//|

<html></code></html>


~~META:
language = en
~~
Jan Kończak

User Tools

Site Tools

Page Tools
