From a7cf48a48cf2be7ab0fe937d62f27b506e5f2240 Mon Sep 17 00:00:00 2001
From: DHANUSH RAJA <155062318+DHANUSHRAJA22@users.noreply.github.com>
Date: Wed, 27 Aug 2025 03:50:12 +0530
Subject: [PATCH] Add Day 7 remote_execute.sh for remote command execution
 challenge.Add Day 7 remote_execute.sh for remote command execution
 challenge.Create remote_execute.sh

---
 Challenges/Day_7/remote_execute.sh | 163 +++++++++++++++++++++++++++++
 1 file changed, 163 insertions(+)
 create mode 100644 Challenges/Day_7/remote_execute.sh

diff --git a/Challenges/Day_7/remote_execute.sh b/Challenges/Day_7/remote_execute.sh
new file mode 100644
index 0000000..1cf4a4c
--- /dev/null
+++ b/Challenges/Day_7/remote_execute.sh
@@ -0,0 +1,163 @@
+#!/bin/bash
+
+# remote_execute.sh - Remote Command Execution Script
+# 
+# Description:
+# This script allows you to execute commands remotely on target hosts using SSH.
+# It takes a target host, username, and command as arguments and executes the 
+# command on the remote host, displaying the output.
+#
+# Usage:
+#   ./remote_execute.sh <target_host> <username> <command>
+#
+# Arguments:
+#   target_host  - The hostname or IP address of the remote host
+#   username     - The username to authenticate with on the remote host
+#   command      - The command to execute on the remote host (use quotes if contains spaces)
+#
+# Examples:
+#   ./remote_execute.sh 192.168.1.100 admin "ls -la"
+#   ./remote_execute.sh server.example.com user "df -h"
+#   ./remote_execute.sh myserver john "uptime"
+#
+# Prerequisites:
+#   - SSH must be installed and configured
+#   - SSH key-based authentication is recommended for security
+#   - The target host must be accessible via SSH
+#
+# Author: BashBlaze Day 7 Challenge
+# Date: $(date +"%Y-%m-%d")
+
+# Function to display usage information
+show_usage() {
+    echo "Usage: $0 <target_host> <username> <command>"
+    echo ""
+    echo "Arguments:"
+    echo "  target_host  - The hostname or IP address of the remote host"
+    echo "  username     - The username to authenticate with on the remote host"
+    echo "  command      - The command to execute on the remote host"
+    echo ""
+    echo "Examples:"
+    echo "  $0 192.168.1.100 admin \"ls -la\""
+    echo "  $0 server.example.com user \"df -h\""
+    echo "  $0 myserver john \"uptime\""
+    echo ""
+    exit 1
+}
+
+# Function to validate arguments
+validate_arguments() {
+    if [ $# -ne 3 ]; then
+        echo "Error: Invalid number of arguments."
+        echo "Expected 3 arguments, got $#."
+        echo ""
+        show_usage
+    fi
+
+    local target_host="$1"
+    local username="$2"
+    local command="$3"
+
+    # Check if target_host is empty
+    if [ -z "$target_host" ]; then
+        echo "Error: Target host cannot be empty."
+        show_usage
+    fi
+
+    # Check if username is empty
+    if [ -z "$username" ]; then
+        echo "Error: Username cannot be empty."
+        show_usage
+    fi
+
+    # Check if command is empty
+    if [ -z "$command" ]; then
+        echo "Error: Command cannot be empty."
+        show_usage
+    fi
+
+    # Basic hostname/IP validation
+    if ! echo "$target_host" | grep -E '^[a-zA-Z0-9.-]+$' > /dev/null; then
+        echo "Error: Invalid target host format."
+        echo "Target host should contain only letters, numbers, dots, and hyphens."
+        show_usage
+    fi
+
+    # Basic username validation
+    if ! echo "$username" | grep -E '^[a-zA-Z0-9_-]+$' > /dev/null; then
+        echo "Error: Invalid username format."
+        echo "Username should contain only letters, numbers, underscores, and hyphens."
+        show_usage
+    fi
+}
+
+# Function to execute remote command
+execute_remote_command() {
+    local target_host="$1"
+    local username="$2"
+    local command="$3"
+
+    echo "Connecting to $username@$target_host..."
+    echo "Executing command: $command"
+    echo "" 
+    echo "=== Remote Command Output ==="
+
+    # Execute the SSH command and capture the exit status
+    ssh -o ConnectTimeout=10 -o StrictHostKeyChecking=no "$username@$target_host" "$command"
+    local ssh_exit_status=$?
+
+    echo ""
+    echo "=== End of Remote Output ==="
+
+    # Check if SSH command was successful
+    if [ $ssh_exit_status -eq 0 ]; then
+        echo "Remote command executed successfully."
+    else
+        echo "Error: Remote command failed with exit status: $ssh_exit_status"
+        case $ssh_exit_status in
+            255)
+                echo "Possible causes: Connection refused, host unreachable, or authentication failed."
+                ;;
+            1)
+                echo "Possible cause: Command not found or command execution failed."
+                ;;
+            *)
+                echo "Check the SSH connection and command syntax."
+                ;;
+        esac
+        exit $ssh_exit_status
+    fi
+}
+
+# Main script execution
+main() {
+    # Display script header
+    echo "===== Remote Command Execution Script ====="
+    echo "BashBlaze Day 7 Challenge"
+    echo ""
+
+    # Validate arguments
+    validate_arguments "$@"
+
+    # Extract arguments
+    local target_host="$1"
+    local username="$2"
+    local command="$3"
+
+    # Check if SSH is available
+    if ! command -v ssh > /dev/null 2>&1; then
+        echo "Error: SSH command not found. Please install SSH client."
+        exit 1
+    fi
+
+    # Execute remote command
+    execute_remote_command "$target_host" "$username" "$command"
+
+    echo ""
+    echo "Script execution completed."
+}
+
+# Check if script is being sourced or executed
+if [[ "${BASH_SOURCE[0]}" == "${0}" ]]; then
+    main "$@"
+fi