Permissions
User Permissions
-rw-r--r-- 12 mark scanner 12.0K Apr 28 10:10 file_name
|[─][─][─]─ [──────] [──────]
| | | | | | |
| | | | | | └─────────► 7. Group
| | | | | └───────────────────► 6. Owner
| | | | └──────────────────────────► 5. Alternate Access Method
| | | └────────────────────────────► 4. Others Permissions
| | └───────────────────────────────► 3. Group Permissions
| └──────────────────────────────────► 2. Owner Permissions
└────────────────────────────────────► 1. File Type
SUID && GUID
SUID GUID
rws-rwx-rwx rwx-rws-rwx
S:If found in the User, it sets the SUID Bit. If found in the Group, it sets the SETGID Bit. It also means that X Flag is set. When the SETUID or SETGID Flags are set on an Executable File, the file is executed with the file’s Owner and/or Group Privileges.
Sticky Bit
STICKY
rws-rws-r-T
T:If found in the Others, it sets the STICKY Bit. It also means that X Flag is set. This Flag is useless on Files.
Numeric Method
SUID = 4
GUID = 2
STICKY = 1
- Check File Permissions
stat -c "%a" File_Name
PASSWD FORMAT
mark:x:1001:1001:mark,,,:/home/mark:/bin/bash
[──] ─ [──] [──] [─────] [────────] [────────]
| | | | | | |
| | | | | | └─► 7. Login Shell
| | | | | └──────────► 6. Home Directory
| | | | └────────────────────► 5. GECOS
| | | └──────────────────────────► 4. GID
| | └───────────────────────────────► 3. UID
| └───────────────────────────────────► 2. Password
└────────────────────────────────────────► 1. Username
SHADOW FORMAT
mark:$6$.n.:17736:0:99999:7:::
[──] [────] [───] ─ [───] ────
| | | | | |||└───────────► 9. Unused
| | | | | ||└────────────► 8. Expiration date
| | | | | |└─────────────► 7. Inactivity Period
| | | | | └──────────────► 6. Warning Period
| | | | └──────────────────► 5. Maximum Password Age
| | | └──────────────────────► 4. Minimum Password Age
| | └──────────────────────────► 3. Last Password Change
| └─────────────────────────────────► 2. Encrypted Password
└────────────────────────────────────────► 1. Username