Linux Security

  1. Filesystem and Data Security
    1. Standard File Permissions
      1. Permission Types
        1. Read Permission
          1. Write Permission
            1. Execute Permission
            2. Permission Representation
              1. Symbolic Notation
                1. Octal Notation
                  1. Binary Representation
                  2. Permission Management
                    1. chmod Command
                      1. umask Configuration
                        1. Default Permissions
                          1. Permission Inheritance
                          2. Ownership Management
                            1. chown Command
                              1. chgrp Command
                                1. Ownership Inheritance
                                  1. Security Implications
                                2. Special File Permissions
                                  1. Set User ID (SUID)
                                    1. Functionality and Purpose
                                      1. Security Implications
                                        1. Identifying SUID Files
                                          1. Common SUID Programs
                                            1. SUID Security Risks
                                            2. Set Group ID (SGID)
                                              1. File SGID Behavior
                                                1. Directory SGID Behavior
                                                  1. Group Inheritance
                                                    1. Identifying SGID Files
                                                    2. Sticky Bit
                                                      1. Directory Protection
                                                        1. Shared Directory Usage
                                                          1. Identifying Sticky Bit
                                                            1. Common Applications
                                                          2. Access Control Lists (ACLs)
                                                            1. ACL Concepts
                                                              1. Extended Permissions
                                                                1. ACL Types
                                                                  1. Mask Calculations
                                                                  2. Viewing ACLs
                                                                    1. getfacl Command
                                                                      1. ACL Output Interpretation
                                                                        1. Default ACL Display
                                                                        2. Setting ACLs
                                                                          1. setfacl Command
                                                                            1. User-specific Permissions
                                                                              1. Group-specific Permissions
                                                                                1. Default ACLs
                                                                                  1. ACL Inheritance
                                                                                  2. ACL Management
                                                                                    1. Modifying Existing ACLs
                                                                                      1. Removing ACLs
                                                                                        1. Copying ACLs
                                                                                          1. Backup and Restore
                                                                                        2. Extended File Attributes
                                                                                          1. Attribute Types
                                                                                            1. Immutable Attribute
                                                                                              1. Append-only Attribute
                                                                                                1. No-dump Attribute
                                                                                                  1. Secure Deletion Attribute
                                                                                                  2. Managing Attributes
                                                                                                    1. chattr Command
                                                                                                      1. Attribute Syntax
                                                                                                        1. Recursive Operations
                                                                                                        2. Viewing Attributes
                                                                                                          1. lsattr Command
                                                                                                            1. Attribute Display
                                                                                                              1. Filtering Options
                                                                                                            2. Filesystem Security Features
                                                                                                              1. Mount Options
                                                                                                                1. noexec Option
                                                                                                                  1. nosuid Option
                                                                                                                    1. nodev Option
                                                                                                                      1. ro Option
                                                                                                                        1. Security Implications
                                                                                                                        2. Filesystem Types
                                                                                                                          1. ext4 Security Features
                                                                                                                            1. XFS Security Features
                                                                                                                              1. Btrfs Security Features
                                                                                                                                1. ZFS Security Features
                                                                                                                              2. Data Encryption
                                                                                                                                1. Full Disk Encryption
                                                                                                                                  1. LUKS Setup
                                                                                                                                    1. Key Management
                                                                                                                                      1. Header Backup
                                                                                                                                        1. Performance Considerations
                                                                                                                                        2. Encrypted Home Directories
                                                                                                                                          1. User-specific Encryption
                                                                                                                                            1. Automatic Mounting
                                                                                                                                              1. Key Derivation
                                                                                                                                              2. File-level Encryption
                                                                                                                                                1. eCryptfs
                                                                                                                                                  1. Setup and Configuration
                                                                                                                                                    1. Directory Encryption
                                                                                                                                                      1. Key Management
                                                                                                                                                      2. fscrypt
                                                                                                                                                        1. Policy Management
                                                                                                                                                          1. Key Derivation
                                                                                                                                                            1. Performance Optimization
                                                                                                                                                          2. Encryption Tools
                                                                                                                                                            1. GnuPG
                                                                                                                                                              1. Symmetric Encryption
                                                                                                                                                                1. Asymmetric Encryption
                                                                                                                                                                  1. Key Management
                                                                                                                                                                    1. Digital Signatures
                                                                                                                                                                    2. OpenSSL
                                                                                                                                                                      1. File Encryption
                                                                                                                                                                        1. Certificate Management
                                                                                                                                                                          1. Hash Functions

                                                                                                                                                                    Previous

                                                                                                                                                                    2. User and Group Management

                                                                                                                                                                    Go to top

                                                                                                                                                                    Next

                                                                                                                                                                    4. Mandatory Access Control (MAC) Frameworks