Tài khoản người sử dụng và phân quyền truy cập tệp tin

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3/6/11 @ Ha Quoc Trung 2009 4
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3/6/11 @ Ha Quoc Trung 2009 5
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3/6/11 @ Ha Quoc Trung 2009 7
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3/6/11 @ Ha Quoc Trung 2009 8
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—[$:H$
$ ls -l
rw-rw- 1 tuananh user1 16 Feb 10 19:12 test1.txt
-rw-rw-rw- 1 tuananh user1 16 Feb 10 19:12 test2.txt
drw-r r 2 tuananh user1 512 Feb 10 19:14 vanban
$ whoami
tuananh
$ cat test1.txt
cat: test1.txt: Permission denied
$ cat test2.txt
Un fichier de test
$ cp test2.txt vanban
cp: vanban: Permission denied
‰=6$AG1$B$
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•  set-uid: -rws
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•  set-gid: - rws
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•  bit sticky
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—[$:H$
$ ls -l /etc/passwd
-rw-rw 1 root root 568 Feb 10 19:12 passwd
$ ls -l /bin/passwd
-rwsrws x 1 root root 3634 Feb 10 19:12 passwd

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$chmod <mode> <files>

set_uid set-gid sticky user group other
rwx x x
1 1 0 111 001 001
6 7 1 1

$ chmod 6711 test
$ ls -l test
-rws s x 1 tuananh user1 Mar 10 10:20 test
$ chmod 711 test

$ ls -l test
-rwx x x 1 tuananh user1 Mar 10 10:20 test$
!&D2$Z€#$0123)$4512$)&7.$SfU$
$chmod <ugoa><+-=><rwsx> <files>
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—[$:H$
$ ls -l test.txt
-rw-rw-r 1 tuananh user1 150 Mar 19 19:12 test.txt
$ chmod o+w test.txt
$ ls -l test.txt
-rw-rw-rw- 1 tuananh user1 150 Mar 19 19:12 test.txt
$ chmod a-rw test.txt
$ ls -l test.txt
1 tuananh user1 150 Mar 19 19:12 test.txt
$ cat test.txt
cat: test.txt: Permission denied
˜M)&$);& D$6=6$0123)$);X>$ZM)&$%&#$4N'$5D$
d$EAF$
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•  set-uid: -rws
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•  set-gid: - rws
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•  bit sticky
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3/6/11 @ Ha Quoc Trung 2009 22
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•  set-uid: -rws
•  set-gid: - rws
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3/6/11 @ Ha Quoc Trung 2009 23
+]6%2$c#4$FYD>.AF$
3/6/11 @ Ha Quoc Trung 2009 24
+]6%2$c#4$FYD>.AF$

3/6/11 @ Ha Quoc Trung 2009 25