Merge pull request #42 from prudvikeshav/linux

Linux

Linux/Script Execution Permissions.md

@@ -1,87 +1,65 @@
-# Problem Statement
-Following security audits, the xFusionCorp Industries security team has rolled out new protocols, including the restriction of direct root SSH login.
+In a bid to automate backup processes, the xFusionCorp Industries sysadmin team has developed a new bash script named *xfusioncorp.sh*. While the script has been distributed to all necessary servers, it lacks executable permissions on *App Server 3* within the Stratos Datacenter.
 
-Your task is to disable direct SSH root login on all app servers within the Stratos Datacenter.
-## Solution
+Your task is to grant executable permissions to the */tmp/xfusioncorp.sh* script on *App Server 3.* Additionally, ensure that all users have the capability to execute it.
 
-To address this requirement, we need to automate the process of disabling direct root SSH login on multiple servers. The solution involves the following steps:
+# Solution:
 
-1. **Define Server Details**: Create arrays to store the server names, SSH usernames, and corresponding passwords.
 
-2. **Iterate Through Servers**: Loop through each server, using the respective username and password to perform SSH operations.
+#### **1. Connect to App Server 3**
 
-3. **Disable Root Login**:
-   - **Connect to Server**: Use `sshpass` to manage SSH login with passwords, avoiding manual intervention.
-   - **Update SSH Configuration**: Modify the SSH configuration file (`/etc/ssh/sshd_config`) to disable root login. This involves:
-     - Commenting out any existing `PermitRootLogin` directives.
-     - Adding or updating the `PermitRootLogin no` directive to restrict root access.
-   - **Restart SSH Service**: Apply the changes by restarting the SSH service to ensure that the new configuration takes effect.
+Start by connecting to App Server 3 via SSH using the `banner` account.
 
-4. **Error Handling and Reporting**: Check the success or failure of each operation and provide appropriate feedback.
+```bash
+ssh banner@stapp03
+```
+
+
+#### **2. Switch to the Superuser (Root)**
+
+Once logged in, switch to the root user to modify the script's permissions.
+
+```bash
+sudo su
+```
+
+
+#### **3. Check the Current Permissions**
+
+Verify the current permissions of the script to understand its current state.
+
+```bash
+ls -al /tmp/xfusioncorp.sh
+```
 
-Here is the enhanced script that implements the above solution:
+
+#### **4. Grant Executable Permissions**
+
+Update the permissions of the script so that all users can execute it.
 
 ```bash
-#!/bin/bash
-
-# Define lists of servers, usernames, and passwords
-servers=("stapp01" "stapp02" "stapp03")
-users=("tony" "steve" "banner")
-passwords=("Ir0nM@n" "Am3ric@" "BigGr33n")
-
-# Loop through each server to apply changes
-for i in "${!servers[@]}"; do
-    server="${servers[$i]}"
-    user="${users[$i]}"
-    password="${passwords[$i]}"
-
-    echo "Processing $server..."
-
-    # SSH into the server and execute commands
-    sshpass -p "$password" ssh -o StrictHostKeyChecking=no "$user@$server" <<EOF
-        # Disable root login in the SSH configuration
-        echo "$password" | sudo -S bash -c "
-            # Backup the current SSH configuration
-            cp /etc/ssh/sshd_config /etc/ssh/sshd_config.bak
-
-            # Disable root login
-            sed -i 's/^#PermitRootLogin .*/PermitRootLogin no/' /etc/ssh/sshd_config
-            sed -i 's/^PermitRootLogin .*/PermitRootLogin no/' /etc/ssh/sshd_config
-
-            # Restart SSH service to apply changes
-            systemctl restart sshd
-        "
-EOF
-
-    # Check the exit status of the SSH command
-    if [ $? -eq 0 ]; then
-        echo "Successfully disabled root login on $server"
-    else
-        echo "Failed to update $server"
-    fi
-
-    echo "---------------------------------"
-done
+chmod 755 /tmp/xfusioncorp.sh
 ```
 
-### Explanation of the Script
+- **Explanation**:
+  - `chmod 755`: This command sets the permissions of the file to `rwxr-xr-x`.
+    - `rwx` (read, write, execute) for the owner (root).
+    - `r-x` (read, execute) for the group (root).
+    - `r-x` (read, execute) for others (all users).
 
-1. **Variables**:
-   - `servers`, `users`, and `passwords` arrays store the necessary details for each server.
+#### **5. Verify the Permissions**
 
-2. **SSH Operations**:
-   - `sshpass -p "$password"`: Manages password-based SSH authentication.
-   - `ssh -o StrictHostKeyChecking=no "$user@$server"`: Connects to each server, bypassing host key checks for automation purposes.
+Check the permissions again to ensure that they have been updated correctly.
 
-3. **Commands Execution**:
-   - **Backup Configuration**: Creates a backup of the current SSH configuration file to safeguard against potential issues.
-   - **Modify Configuration**: Updates the SSH configuration to disable root login.
-   - **Restart SSH Service**: Ensures that the new configuration is applied immediately.
+```bash
+ls -al /tmp/xfusioncorp.sh
+```
+
+
+#### **6. Execute the Script**
 
-4. **Error Handling**:
-   - Checks the success of each SSH command and reports accordingly.
+Run the script to ensure it works as expected.
 
-**Security Considerations**:
+```bash
+. /tmp/xfusioncorp.sh
+```
 
-- **Password Handling**: The script uses passwords directly, which could be a security risk. Consider using SSH keys and configuring `sudo` for passwordless access to specific commands for a more secure solution.
-- **Testing**: Before deploying the script in a production environment, thoroughly test it in a controlled setting to verify its functionality and avoid unintended disruptions.