manage-servers/server-actions/server_actions.go

package serveractions

import (
	"context"
	"fmt"
	"net"
	"os"
	"os/exec"
	"regexp"
	"strings"
	"time"

	"golang.org/x/crypto/ssh"
)

var Debug bool

func LogDebug(format string, v ...interface{}) {
	if Debug {
		fmt.Fprintf(os.Stderr, "[DEBUG] "+format+"\n", v...)
	}
}

func WakeServer(name string, servers []Server) {
	for _, s := range servers {
		if s.Name == name {
			fmt.Printf("Sending Wake-on-LAN packet to %s (%s)...\n", s.Name, s.Mac)
			err := sendMagicPacket(s.Mac, s.IP)
			if err != nil {
				fmt.Printf("Error sending packet from local network: %v\n", err)
			} else {
				fmt.Println("Local WOL packet sent successfully.")
			}

			// Try to wake via proxy if there's another online server in the same subnet
			LogDebug("Checking for online servers in the same subnet to use as a proxy...")
			for _, other := range servers {
				if other.Name != s.Name && other.IP != "" && strings.HasPrefix(other.IP, s.IP[:strings.LastIndex(s.IP, ".")]) {
					// Only use as proxy if we have credentials
					if other.SSHUser != "" && other.SSHPass != "" {
						if PingHost(other.IP) {
							fmt.Printf("Attempting to wake %s via proxy %s...\n", s.Name, other.Name)
							err := WakeServerRemote(other, s.Mac)
							if err != nil {
								LogDebug("Failed to wake via proxy %s: %v", other.Name, err)
							} else {
								fmt.Printf("Wake signal sent via proxy %s.\n", other.Name)
								return
							}
						}
					}
				}
			}

			return
		}
	}
	fmt.Printf("Server '%s' not found in configuration.\n", name)
}

func WakeServerRemote(proxy Server, targetMac string) error {
	// Send magic packet from the proxy server using a simple shell command
	// We use python or similar if available, or just a simple bash command that constructs the packet
	// constructing the packet in bash:
	// echo -e $(printf 'f%.0s' {1..12}; printf "$(echo $MAC | sed 's/://g')%.0s" {1..16}) | xxd -r -p | nc -w1 -u -b 255.255.255.255 9

	// A simpler way if wakeonlan is installed: wakeonlan $MAC
	// But let's assume we might need to construct it or use a common tool.
	// We'll try common tools first.
	cmd := fmt.Sprintf("wakeonlan %s || ether-wake %s || (printf '%%b' \"$(printf '\\\\xff\\\\xff\\\\xff\\\\xff\\\\xff\\\\xff'; for i in {1..16}; do printf '%s' | sed 's/\\([0-9a-fA-F]\\{2\\}\\)/\\\\x\\1/g'; done)\" | nc -w1 -u -b 255.255.255.255 9)", targetMac, targetMac, targetMac)

	return executeSSHCommand(proxy, cmd)
}

func WakeAllServers(servers []Server) {
	fmt.Println("Waking all servers...")
	for _, s := range servers {
		WakeServer(s.Name, servers)
	}
}

func CheckServersStatus(servers []Server) {
	fmt.Println("Checking server status...")
	for _, s := range servers {
		if s.IP == "" {
			fmt.Printf("  - %-20s [SKIPPED] (No IP configured)\n", s.Name)
			continue
		}
		online := PingHost(s.IP)
		status := "Offline"
		if online {
			status = "Online"
		}
		fmt.Printf("  - %-20s [%s]\n", s.Name, status)
	}
}

func PingHost(host string) bool {
	LogDebug("Pinging host: %s", host)
	ctx, cancel := context.WithTimeout(context.Background(), 2*time.Second)
	defer cancel()

	cmd := exec.CommandContext(ctx, "ping", "-c", "1", host)

	err := cmd.Run()
	if err != nil {
		LogDebug("Ping failed for %s: %v", host, err)
	} else {
		LogDebug("Ping successful for %s", host)
	}
	return err == nil
}

// Creates and sends a magic packet to the specified MAC address.
// Supports cross-VLAN by sending to both general and subnet-directed broadcast.
func sendMagicPacket(macAddr string, ip string) error {
	hwAddr, err := net.ParseMAC(macAddr)
	if err != nil {
		return fmt.Errorf("invalid mac address '%s': %w", macAddr, err)
	}

	magicPacket := make([]byte, 102)
	for i := 0; i < 6; i++ {
		magicPacket[i] = 0xFF
	}
	for i := 1; i <= 16; i++ {
		copy(magicPacket[i*6:], hwAddr)
	}

	// List of addresses to try sending the WOL packet to
	// List of addresses to try sending the WOL packet to
	broadcastAddresses := []string{"255.255.255.255"}

	// If a valid IP is provided, calculate the directed broadcast address (assuming /24 subnet)
	if ip != "" {
		ipParts := strings.Split(ip, ".")
		if len(ipParts) == 4 {
			directedBroadcast := fmt.Sprintf("%s.%s.%s.255", ipParts[0], ipParts[1], ipParts[2])
			if directedBroadcast != "255.255.255.255" {
				broadcastAddresses = append(broadcastAddresses, directedBroadcast)
			}
			broadcastAddresses = append(broadcastAddresses, ip)
		}
	}

	ports := []int{7, 9}
	for _, addr := range broadcastAddresses {
		for _, port := range ports {
			fullAddr := fmt.Sprintf("%s:%d", addr, port)
			LogDebug("Sending magic packet to %s", fullAddr)
			for i := 0; i < 3; i++ {
				conn, err := net.Dial("udp", fullAddr)
				if err == nil {
					conn.Write(magicPacket)
					conn.Close()
				}
				time.Sleep(10 * time.Millisecond)
			}
		}
	}

	return nil
}

func ShutdownServer(name string, servers []Server) {
	for _, s := range servers {
		if s.Name == name {
			fmt.Printf("Attempting to shutdown %s...\n", s.Name)
			err := executeSSHCommand(s, "sudo shutdown -h now")
			if err != nil {
				fmt.Printf("Error shutting down %s: %v\n", s.Name, err)
			} else {
				fmt.Printf("%s is shutting down.\n", s.Name)
			}
			return
		}
	}
	fmt.Printf("Server '%s' not found in configuration.\n", name)
}

func RebootServer(name string, servers []Server) {
	for _, s := range servers {
		if s.Name == name {
			fmt.Printf("Attempting to reboot %s...\n", s.Name)
			err := executeSSHCommand(s, "sudo reboot")
			if err != nil {
				fmt.Printf("Error rebooting %s: %v\n", s.Name, err)
			} else {
				fmt.Printf("%s is rebooting.\n", s.Name)
			}
			return
		}
	}
	fmt.Printf("Server '%s' not found in configuration.\n", name)
}

func GetSSHClient(server Server) (*ssh.Client, error) {
	config := &ssh.ClientConfig{
		User: server.SSHUser,
		Auth: []ssh.AuthMethod{
			// Explicitly using ONLY Password and Keyboard-Interactive to avoid
			// trying local SSH keys which might trigger "Too many attempts"
			ssh.Password(server.SSHPass),
			ssh.KeyboardInteractive(func(user, instruction string, questions []string, echos []bool) ([]string, error) {
				answers := make([]string, len(questions))
				for i := range questions {
					answers[i] = server.SSHPass
				}
				return answers, nil
			}),
		},
		HostKeyCallback: ssh.InsecureIgnoreHostKey(),
		Timeout:         10 * time.Second,
	}

	return ssh.Dial("tcp", server.IP+":22", config)
}

func executeSSHCommand(server Server, command string) error {
	client, err := GetSSHClient(server)
	if err != nil {
		return fmt.Errorf("failed to connect: %w", err)
	}
	defer client.Close()

	LogDebug("SSH connection established to %s", server.IP)

	session, err := client.NewSession()
	if err != nil {
		return fmt.Errorf("failed to create session: %w", err)
	}
	defer session.Close()

	LogDebug("Executing SSH command: %s", command)
	output, err := session.CombinedOutput(command)
	if err != nil {
		LogDebug("SSH command failed: %v, Output: %s", err, string(output))
		return fmt.Errorf("failed to run command: %w", err)
	}
	LogDebug("SSH command output: %s", string(output))

	return nil
}
func GetMacAddress(ip string) (string, error) {
	// Ping the host to ensure it's in the ARP table
	PingHost(ip)

	LogDebug("Looking for MAC address for IP: %s", ip)
	// Run arp -a to get the ARP table
	ctx, cancel := context.WithTimeout(context.Background(), 2*time.Second)
	defer cancel()

	cmd := exec.CommandContext(ctx, "arp", "-a")
	output, err := cmd.CombinedOutput()
	if err != nil {
		LogDebug("arp -a failed: %v", err)
		return "", fmt.Errorf("error running arp: %v", err)
	}

	LogDebug("arp output received (%d bytes)", len(output))
	// Regex to find the MAC address for the given IP
	// Matches: (IP) at MAC or variations
	lines := strings.Split(string(output), "\n")
	for _, line := range lines {
		if strings.Contains(line, "("+ip+")") || strings.Contains(line, " "+ip+" ") {
			LogDebug("Found matching line in arp table: %s", line)
			// Extract MAC address - usually looking for 6 pairs of hex digits separated by : or -
			re := regexp.MustCompile(`([0-9a-fA-F]{1,2}[:\-]){5}[0-9a-fA-F]{1,2}`)
			mac := re.FindString(line)
			if mac != "" {
				LogDebug("Extracted MAC: %s", mac)
				return mac, nil
			}
		}
	}

	LogDebug("No MAC address found in arp table for IP %s", ip)
	return "", fmt.Errorf("MAC address not found for IP %s", ip)
}

func GetMacAddressSSH(ip, user, pass string) (string, error) {
	if user == "" || pass == "" {
		return "", fmt.Errorf("SSH credentials required for remote MAC lookup")
	}

	LogDebug("Attempting to get MAC address via SSH for %s@%s", user, ip)

	server := Server{
		IP:      ip,
		SSHUser: user,
		SSHPass: pass,
	}

	// Try common commands to get MAC on Linux/Unix
	// ip link, ifconfig, etc.
	cmd := "cat /sys/class/net/$(ip route get 8.8.8.8 | awk '{print $5}')/address 2>/dev/null || ifconfig | grep -E 'ether|HWaddr' | awk '{print $2}' | head -n 1"

	config := &ssh.ClientConfig{
		User: server.SSHUser,
		Auth: []ssh.AuthMethod{
			ssh.Password(server.SSHPass),
			ssh.KeyboardInteractive(func(user, instruction string, questions []string, echos []bool) ([]string, error) {
				answers := make([]string, len(questions))
				for i := range questions {
					answers[i] = server.SSHPass
				}
				return answers, nil
			}),
		},
		HostKeyCallback: ssh.InsecureIgnoreHostKey(),
		Timeout:         5 * time.Second,
	}

	client, err := ssh.Dial("tcp", server.IP+":22", config)
	if err != nil {
		return "", fmt.Errorf("SSH dial failed: %w", err)
	}
	defer client.Close()

	session, err := client.NewSession()
	if err != nil {
		return "", fmt.Errorf("failed to create session: %w", err)
	}
	defer session.Close()

	output, err := session.CombinedOutput(cmd)
	if err != nil {
		return "", fmt.Errorf("SSH command failed: %w", err)
	}

	mac := strings.TrimSpace(string(output))
	// Validate MAC format
	re := regexp.MustCompile(`([0-9a-fA-F]{1,2}[:\-]){5}[0-9a-fA-F]{1,2}`)
	mac = re.FindString(mac)

	if mac == "" {
		return "", fmt.Errorf("could not extract MAC address from SSH output")
	}

	LogDebug("Successfully retrieved MAC via SSH: %s", mac)
	return mac, nil
}