fake root

Well guys, you must know that root is supreme master of the unix operating systems like Linux, Hurd, Solaris, HP-UX, BSDs, AIX and there still many of them. root account is lord of the system where any other accounts are under its orders, rules, legacy and/or policy.

root is identical to UID 0 and any other accounts with different various UID number from 1 to 65535 in Linux. Maximum number of UIDs depends on the flavor of the operating systems. Let's take a look at our sample /etc/passwd

root:x:0:0::/root:/bin/bash

bin:x:1:1:bin:/bin:/bin/false

daemon:x:2:2:daemon:/sbin:/bin/false

adm:x:3:4:adm:/var/log:/bin/false

lp:x:4:7:lp:/var/spool/lpd:/bin/false

sync:x:5:0:sync:/sbin:/bin/sync

shutdown:x:6:0:shutdown:/sbin:/sbin/shutdown

halt:x:7:0:halt:/sbin:/sbin/halt

mail:x:8:12:mail:/:/bin/false

news:x:9:13:news:/usr/lib/news:/bin/false

uucp:x:10:14:uucp:/var/spool/uucppublic:/bin/false

operator:x:11:0:operator:/root:/bin/bash

games:x:12:100:games:/usr/games:/bin/false

ftp:x:14:50::/home/ftp:/bin/false

smmsp:x:25:25:smmsp:/var/spool/clientmqueue:/bin/false

mysql:x:27:27:MySQL:/var/lib/mysql:/bin/false

rpc:x:32:32:RPC portmap user:/:/bin/false

sshd:x:33:33:sshd:/:/bin/false

gdm:x:42:42:GDM:/var/state/gdm:/bin/bash

apache:x:80:80:User for Apache:/srv/httpd:/bin/false

messagebus:x:81:81:User for D-BUS:/var/run/dbus:/bin/false

haldaemon:x:82:82:User for HAL:/var/run/hald:/bin/false

pop:x:90:90:POP:/:/bin/false

nobody:x:99:99:nobody:/:/bin/false

each value is delimited by a colon. Well let's focus on the first line because this is what we are gonna learn.

root:x:0:0::/root:/bin/bash

the first value is root that means this is the name of account.

the second value is x which means that the password is encrypted and the encrypted password is encrypted password is located on /etc/shadow. the third one is User Identity (UID). the fourth is group Identity (GID). the fifth is description of the account and in this case we have no description. the sixth is the home directory and the seventh is the default shell for the account.

then let's make a user account and assign a password to it. let's call it "fruit".

useradd fruit

passwd fruit

let's change the fruit UID and GID to 0 and (zero) and root UID to 100 and GID to 1000. fruit has taken all the privileges that root once had