script for modifying hardware of a vm

salt/hypervisor/tools/sbin/so-kvm-modify-hardware

@@ -0,0 +1,186 @@
+#!/usr/bin/env python3
+
+# Copyright Security Onion Solutions LLC and/or licensed to Security Onion Solutions LLC under one
+# or more contributor license agreements. Licensed under the Elastic License 2.0 as shown at
+# https://securityonion.net/license; you may not use this file except in compliance with the
+# Elastic License 2.0.
+
+"""
+Script to modify hardware parameters of a KVM virtual machine.
+
+Usage:
+    python so-kvm-modify-hardware.py -v <vm_name> [-c <cpu_count>] [-m <memory_amount>] [-p <pci_id>]
+
+Example:
+    python so-kvm-modify-hardware.py -v my_vm -c 4 -m 8192 -p 0000:00:1f.2
+"""
+
+import argparse
+import logging
+import sys
+import time
+import libvirt
+import xml.etree.ElementTree as ET
+
+def setup_logging():
+    logger = logging.getLogger('so-kvm-modify-hardware')
+    logger.setLevel(logging.INFO)
+
+    # Create handlers
+    c_handler = logging.StreamHandler()
+    f_handler = logging.FileHandler('/opt/so/log/hypervisor/so-kvm-modify-hardware.log')
+    c_handler.setLevel(logging.INFO)
+    f_handler.setLevel(logging.INFO)
+
+    # Create formatter and add it to handlers
+    formatter = logging.Formatter('%(asctime)s - %(levelname)s - %(message)s')
+    c_handler.setFormatter(formatter)
+    f_handler.setFormatter(formatter)
+
+    # Add handlers to the logger
+    logger.addHandler(c_handler)
+    logger.addHandler(f_handler)
+    return logger
+
+def parse_arguments():
+    parser = argparse.ArgumentParser(description='Modify hardware parameters of a KVM virtual machine.')
+    parser.add_argument('-v', '--vm', required=True, help='Name of the virtual machine to modify.')
+    parser.add_argument('-c', '--cpu', type=int, help='Number of virtual CPUs to assign.')
+    parser.add_argument('-m', '--memory', type=int, help='Amount of memory to assign in MiB.')
+    parser.add_argument('-p', '--pci', help='PCI hardware ID to passthrough to the VM (e.g., 0000:00:1f.2).')
+    args = parser.parse_args()
+    return args
+
+def stop_vm(conn, vm_name, logger):
+    try:
+        dom = conn.lookupByName(vm_name)
+        if dom.isActive():
+            logger.info(f"Shutting down VM '{vm_name}'...")
+            dom.shutdown()
+            # Wait for the VM to shut down
+            while dom.isActive():
+                time.sleep(1)
+            logger.info(f"VM '{vm_name}' has been stopped.")
+        else:
+            logger.info(f"VM '{vm_name}' is already stopped.")
+        return dom
+    except libvirt.libvirtError as e:
+        logger.error(f"Failed to stop VM '{vm_name}': {e}")
+        sys.exit(1)
+
+def modify_vm(dom, cpu_count, memory_amount, pci_id, logger):
+    try:
+        # Get the XML description of the VM
+        xml_desc = dom.XMLDesc()
+        root = ET.fromstring(xml_desc)
+
+        # Modify CPU count
+        if cpu_count is not None:
+            vcpu_elem = root.find('./vcpu')
+            if vcpu_elem is not None:
+                vcpu_elem.text = str(cpu_count)
+                logger.info(f"Set CPU count to {cpu_count}.")
+            else:
+                logger.error("Could not find <vcpu> element in XML.")
+                sys.exit(1)
+
+        # Modify memory amount
+        if memory_amount is not None:
+            memory_elem = root.find('./memory')
+            current_memory_elem = root.find('./currentMemory')
+            if memory_elem is not None and current_memory_elem is not None:
+                memory_elem.text = str(memory_amount * 1024)  # Convert MiB to KiB
+                current_memory_elem.text = str(memory_amount * 1024)
+                logger.info(f"Set memory to {memory_amount} MiB.")
+            else:
+                logger.error("Could not find <memory> elements in XML.")
+                sys.exit(1)
+
+        # Add PCI device passthrough
+        if pci_id is not None:
+            devices_elem = root.find('./devices')
+            if devices_elem is not None:
+                hostdev_elem = ET.SubElement(devices_elem, 'hostdev', attrib={
+                    'mode': 'subsystem',
+                    'type': 'pci',
+                    'managed': 'yes'
+                })
+                source_elem = ET.SubElement(hostdev_elem, 'source')
+                domain_id, bus_slot_func = pci_id.split(':')
+                bus_slot, function = bus_slot_func.split('.')
+                address_attrs = {
+                    'domain': f'0x{domain_id}',
+                    'bus': f'0x{bus_slot}',
+                    'slot': f'0x{bus_slot}',
+                    'function': f'0x{function}'
+                }
+                ET.SubElement(source_elem, 'address', attrib=address_attrs)
+                logger.info(f"Added PCI device passthrough for {pci_id}.")
+            else:
+                logger.error("Could not find <devices> element in XML.")
+                sys.exit(1)
+
+        # Convert XML back to string
+        new_xml_desc = ET.tostring(root, encoding='unicode')
+        return new_xml_desc
+    except Exception as e:
+        logger.error(f"Failed to modify VM XML: {e}")
+        sys.exit(1)
+
+def redefine_vm(conn, new_xml_desc, logger):
+    try:
+        conn.defineXML(new_xml_desc)
+        logger.info("VM redefined with new hardware parameters.")
+    except libvirt.libvirtError as e:
+        logger.error(f"Failed to redefine VM: {e}")
+        sys.exit(1)
+
+def start_vm(dom, logger):
+    try:
+        dom.create()
+        logger.info("VM started successfully.")
+    except libvirt.libvirtError as e:
+        logger.error(f"Failed to start VM: {e}")
+        sys.exit(1)
+
+def main():
+    try:
+        logger = setup_logging()
+        args = parse_arguments()
+
+        vm_name = args.vm
+        cpu_count = args.cpu
+        memory_amount = args.memory
+        pci_id = args.pci
+
+        # Connect to libvirt
+        try:
+            conn = libvirt.open(None)
+        except libvirt.libvirtError as e:
+            logger.error(f"Failed to open connection to libvirt: {e}")
+            sys.exit(1)
+
+        # Stop VM if running
+        dom = stop_vm(conn, vm_name, logger)
+
+        # Modify VM XML
+        new_xml_desc = modify_vm(dom, cpu_count, memory_amount, pci_id, logger)
+
+        # Redefine VM
+        redefine_vm(conn, new_xml_desc, logger)
+
+        # Start VM
+        dom = conn.lookupByName(vm_name)
+        start_vm(dom, logger)
+
+        # Close connection
+        conn.close()
+    except KeyboardInterrupt:
+        logger.error("Operation cancelled by user.")
+        sys.exit(1)
+    except Exception as e:
+        logger.error(f"An error occurred: {e}")
+        sys.exit(1)
+
+if __name__ == '__main__':
+    main()